gcc/builtins.c

   1 /* Expand builtin functions.
   2    Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
   3    2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
  20 02110-1301, USA.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "tm.h"
  26 #include "machmode.h"
  27 #include "real.h"
  28 #include "rtl.h"
  29 #include "tree.h"
  30 #include "tree-gimple.h"
  31 #include "flags.h"
  32 #include "regs.h"
  33 #include "hard-reg-set.h"
  34 #include "except.h"
  35 #include "function.h"
  36 #include "insn-config.h"
  37 #include "expr.h"
  38 #include "optabs.h"
  39 #include "libfuncs.h"
  40 #include "recog.h"
  41 #include "output.h"
  42 #include "typeclass.h"
  43 #include "toplev.h"
  44 #include "predict.h"
  45 #include "tm_p.h"
  46 #include "target.h"
  47 #include "langhooks.h"
  48 #include "basic-block.h"
  49 #include "tree-mudflap.h"
  50
  51 #ifndef PAD_VARARGS_DOWN
  52 #define PAD_VARARGS_DOWN BYTES_BIG_ENDIAN
  53 #endif
  54
  55 /* Define the names of the builtin function types and codes.  */
  56 const char *const built_in_class_names[4]
  57   = {"NOT_BUILT_IN", "BUILT_IN_FRONTEND", "BUILT_IN_MD", "BUILT_IN_NORMAL"};
  58
  59 #define DEF_BUILTIN(X, N, C, T, LT, B, F, NA, AT, IM, COND) #X,
  60 const char * built_in_names[(int) END_BUILTINS] =
  61 {
  62 #include "builtins.def"
  63 };
  64 #undef DEF_BUILTIN
  65
  66 /* Setup an array of _DECL trees, make sure each element is
  67    initialized to NULL_TREE.  */
  68 tree built_in_decls[(int) END_BUILTINS];
  69 /* Declarations used when constructing the builtin implicitly in the compiler.
  70    It may be NULL_TREE when this is invalid (for instance runtime is not
  71    required to implement the function call in all cases).  */
  72 tree implicit_built_in_decls[(int) END_BUILTINS];
  73
  74 static int get_pointer_alignment (tree, unsigned int);
  75 static const char *c_getstr (tree);
  76 static rtx c_readstr (const char *, enum machine_mode);
  77 static int target_char_cast (tree, char *);
  78 static rtx get_memory_rtx (tree, tree);
  79 static tree build_string_literal (int, const char *);
  80 static int apply_args_size (void);
  81 static int apply_result_size (void);
  82 #if defined (HAVE_untyped_call) || defined (HAVE_untyped_return)
  83 static rtx result_vector (int, rtx);
  84 #endif
  85 static rtx expand_builtin_setjmp (tree, rtx);
  86 static void expand_builtin_update_setjmp_buf (rtx);
  87 static void expand_builtin_prefetch (tree);
  88 static rtx expand_builtin_apply_args (void);
  89 static rtx expand_builtin_apply_args_1 (void);
  90 static rtx expand_builtin_apply (rtx, rtx, rtx);
  91 static void expand_builtin_return (rtx);
  92 static enum type_class type_to_class (tree);
  93 static rtx expand_builtin_classify_type (tree);
  94 static void expand_errno_check (tree, rtx);
  95 static rtx expand_builtin_mathfn (tree, rtx, rtx);
  96 static rtx expand_builtin_mathfn_2 (tree, rtx, rtx);
  97 static rtx expand_builtin_mathfn_3 (tree, rtx, rtx);
  98 static rtx expand_builtin_int_roundingfn (tree, rtx, rtx);
  99 static rtx expand_builtin_args_info (tree);
 100 static rtx expand_builtin_next_arg (void);
 101 static rtx expand_builtin_va_start (tree);
 102 static rtx expand_builtin_va_end (tree);
 103 static rtx expand_builtin_va_copy (tree);
 104 static rtx expand_builtin_memcmp (tree, tree, rtx, enum machine_mode);
 105 static rtx expand_builtin_strcmp (tree, rtx, enum machine_mode);
 106 static rtx expand_builtin_strncmp (tree, rtx, enum machine_mode);
 107 static rtx builtin_memcpy_read_str (void *, HOST_WIDE_INT, enum machine_mode);
 108 static rtx expand_builtin_strcat (tree, tree, rtx, enum machine_mode);
 109 static rtx expand_builtin_strncat (tree, rtx, enum machine_mode);
 110 static rtx expand_builtin_strspn (tree, rtx, enum machine_mode);
 111 static rtx expand_builtin_strcspn (tree, rtx, enum machine_mode);
 112 static rtx expand_builtin_memcpy (tree, rtx, enum machine_mode);
 113 static rtx expand_builtin_mempcpy (tree, tree, rtx, enum machine_mode, int);
 114 static rtx expand_builtin_memmove (tree, tree, rtx, enum machine_mode, tree);
 115 static rtx expand_builtin_bcopy (tree);
 116 static rtx expand_builtin_strcpy (tree, tree, rtx, enum machine_mode);
 117 static rtx expand_builtin_stpcpy (tree, rtx, enum machine_mode);
 118 static rtx builtin_strncpy_read_str (void *, HOST_WIDE_INT, enum machine_mode);
 119 static rtx expand_builtin_strncpy (tree, rtx, enum machine_mode);
 120 static rtx builtin_memset_read_str (void *, HOST_WIDE_INT, enum machine_mode);
 121 static rtx builtin_memset_gen_str (void *, HOST_WIDE_INT, enum machine_mode);
 122 static rtx expand_builtin_memset (tree, rtx, enum machine_mode, tree);
 123 static rtx expand_builtin_bzero (tree);
 124 static rtx expand_builtin_strlen (tree, rtx, enum machine_mode);
 125 static rtx expand_builtin_strstr (tree, tree, rtx, enum machine_mode);
 126 static rtx expand_builtin_strpbrk (tree, tree, rtx, enum machine_mode);
 127 static rtx expand_builtin_strchr (tree, tree, rtx, enum machine_mode);
 128 static rtx expand_builtin_strrchr (tree, tree, rtx, enum machine_mode);
 129 static rtx expand_builtin_alloca (tree, rtx);
 130 static rtx expand_builtin_unop (enum machine_mode, tree, rtx, rtx, optab);
 131 static rtx expand_builtin_frame_address (tree, tree);
 132 static rtx expand_builtin_fputs (tree, rtx, bool);
 133 static rtx expand_builtin_printf (tree, rtx, enum machine_mode, bool);
 134 static rtx expand_builtin_fprintf (tree, rtx, enum machine_mode, bool);
 135 static rtx expand_builtin_sprintf (tree, rtx, enum machine_mode);
 136 static tree stabilize_va_list (tree, int);
 137 static rtx expand_builtin_expect (tree, rtx);
 138 static tree fold_builtin_constant_p (tree);
 139 static tree fold_builtin_classify_type (tree);
 140 static tree fold_builtin_strlen (tree);
 141 static tree fold_builtin_inf (tree, int);
 142 static tree fold_builtin_nan (tree, tree, int);
 143 static int validate_arglist (tree, ...);
 144 static bool integer_valued_real_p (tree);
 145 static tree fold_trunc_transparent_mathfn (tree, tree);
 146 static bool readonly_data_expr (tree);
 147 static rtx expand_builtin_fabs (tree, rtx, rtx);
 148 static rtx expand_builtin_signbit (tree, rtx);
 149 static tree fold_builtin_cabs (tree, tree);
 150 static tree fold_builtin_sqrt (tree, tree);
 151 static tree fold_builtin_cbrt (tree, tree);
 152 static tree fold_builtin_pow (tree, tree, tree);
 153 static tree fold_builtin_powi (tree, tree, tree);
 154 static tree fold_builtin_sin (tree);
 155 static tree fold_builtin_cos (tree, tree, tree);
 156 static tree fold_builtin_tan (tree);
 157 static tree fold_builtin_atan (tree, tree);
 158 static tree fold_builtin_trunc (tree, tree);
 159 static tree fold_builtin_floor (tree, tree);
 160 static tree fold_builtin_ceil (tree, tree);
 161 static tree fold_builtin_round (tree, tree);
 162 static tree fold_builtin_int_roundingfn (tree, tree);
 163 static tree fold_builtin_bitop (tree, tree);
 164 static tree fold_builtin_memcpy (tree, tree);
 165 static tree fold_builtin_mempcpy (tree, tree, int);
 166 static tree fold_builtin_memmove (tree, tree);
 167 static tree fold_builtin_strchr (tree, tree);
 168 static tree fold_builtin_memcmp (tree);
 169 static tree fold_builtin_strcmp (tree);
 170 static tree fold_builtin_strncmp (tree);
 171 static tree fold_builtin_signbit (tree, tree);
 172 static tree fold_builtin_copysign (tree, tree, tree);
 173 static tree fold_builtin_isascii (tree);
 174 static tree fold_builtin_toascii (tree);
 175 static tree fold_builtin_isdigit (tree);
 176 static tree fold_builtin_fabs (tree, tree);
 177 static tree fold_builtin_abs (tree, tree);
 178 static tree fold_builtin_unordered_cmp (tree, tree, enum tree_code,
 179                                         enum tree_code);
 180 static tree fold_builtin_1 (tree, tree, bool);
 181
 182 static tree fold_builtin_strpbrk (tree, tree);
 183 static tree fold_builtin_strstr (tree, tree);
 184 static tree fold_builtin_strrchr (tree, tree);
 185 static tree fold_builtin_strcat (tree);
 186 static tree fold_builtin_strncat (tree);
 187 static tree fold_builtin_strspn (tree);
 188 static tree fold_builtin_strcspn (tree);
 189 static tree fold_builtin_sprintf (tree, int);
 190
 191 static rtx expand_builtin_object_size (tree);
 192 static rtx expand_builtin_memory_chk (tree, rtx, enum machine_mode,
 193                                       enum built_in_function);
 194 static void maybe_emit_chk_warning (tree, enum built_in_function);
 195 static void maybe_emit_sprintf_chk_warning (tree, enum built_in_function);
 196 static tree fold_builtin_object_size (tree);
 197 static tree fold_builtin_strcat_chk (tree, tree);
 198 static tree fold_builtin_strncat_chk (tree, tree);
 199 static tree fold_builtin_sprintf_chk (tree, enum built_in_function);
 200 static tree fold_builtin_printf (tree, tree, bool, enum built_in_function);
 201 static tree fold_builtin_fprintf (tree, tree, bool, enum built_in_function);
 202
 203 /* Return true if NODE should be considered for inline expansion regardless
 204    of the optimization level.  This means whenever a function is invoked with
 205    its "internal" name, which normally contains the prefix "__builtin".  */
 206
 207 static bool called_as_built_in (tree node)
 208 {
 209   const char *name = IDENTIFIER_POINTER (DECL_NAME (node));
 210   if (strncmp (name, "__builtin_", 10) == 0)
 211     return true;
 212   if (strncmp (name, "__sync_", 7) == 0)
 213     return true;
 214   return false;
 215 }
 216
 217 /* Return the alignment in bits of EXP, a pointer valued expression.
 218    But don't return more than MAX_ALIGN no matter what.
 219    The alignment returned is, by default, the alignment of the thing that
 220    EXP points to.  If it is not a POINTER_TYPE, 0 is returned.
 221
 222    Otherwise, look at the expression to see if we can do better, i.e., if the
 223    expression is actually pointing at an object whose alignment is tighter.  */
 224
 225 static int
 226 get_pointer_alignment (tree exp, unsigned int max_align)
 227 {
 228   unsigned int align, inner;
 229
 230   if (! POINTER_TYPE_P (TREE_TYPE (exp)))
 231     return 0;
 232
 233   align = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp)));
 234   align = MIN (align, max_align);
 235
 236   while (1)
 237     {
 238       switch (TREE_CODE (exp))
 239         {
 240         case NOP_EXPR:
 241         case CONVERT_EXPR:
 242         case NON_LVALUE_EXPR:
 243           exp = TREE_OPERAND (exp, 0);
 244           if (! POINTER_TYPE_P (TREE_TYPE (exp)))
 245             return align;
 246
 247           inner = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp)));
 248           align = MIN (inner, max_align);
 249           break;
 250
 251         case PLUS_EXPR:
 252           /* If sum of pointer + int, restrict our maximum alignment to that
 253              imposed by the integer.  If not, we can't do any better than
 254              ALIGN.  */
 255           if (! host_integerp (TREE_OPERAND (exp, 1), 1))
 256             return align;
 257
 258           while (((tree_low_cst (TREE_OPERAND (exp, 1), 1))
 259                   & (max_align / BITS_PER_UNIT - 1))
 260                  != 0)
 261             max_align >>= 1;
 262
 263           exp = TREE_OPERAND (exp, 0);
 264           break;
 265
 266         case ADDR_EXPR:
 267           /* See what we are pointing at and look at its alignment.  */
 268           exp = TREE_OPERAND (exp, 0);
 269           if (TREE_CODE (exp) == FUNCTION_DECL)
 270             align = FUNCTION_BOUNDARY;
 271           else if (DECL_P (exp))
 272             align = DECL_ALIGN (exp);
 273 #ifdef CONSTANT_ALIGNMENT
 274           else if (CONSTANT_CLASS_P (exp))
 275             align = CONSTANT_ALIGNMENT (exp, align);
 276 #endif
 277           return MIN (align, max_align);
 278
 279         default:
 280           return align;
 281         }
 282     }
 283 }
 284
 285 /* Compute the length of a C string.  TREE_STRING_LENGTH is not the right
 286    way, because it could contain a zero byte in the middle.
 287    TREE_STRING_LENGTH is the size of the character array, not the string.
 288
 289    ONLY_VALUE should be nonzero if the result is not going to be emitted
 290    into the instruction stream and zero if it is going to be expanded.
 291    E.g. with i++ ? "foo" : "bar", if ONLY_VALUE is nonzero, constant 3
 292    is returned, otherwise NULL, since
 293    len = c_strlen (src, 1); if (len) expand_expr (len, ...); would not
 294    evaluate the side-effects.
 295
 296    The value returned is of type `ssizetype'.
 297
 298    Unfortunately, string_constant can't access the values of const char
 299    arrays with initializers, so neither can we do so here.  */
 300
 301 tree
 302 c_strlen (tree src, int only_value)
 303 {
 304   tree offset_node;
 305   HOST_WIDE_INT offset;
 306   int max;
 307   const char *ptr;
 308
 309   STRIP_NOPS (src);
 310   if (TREE_CODE (src) == COND_EXPR
 311       && (only_value || !TREE_SIDE_EFFECTS (TREE_OPERAND (src, 0))))
 312     {
 313       tree len1, len2;
 314
 315       len1 = c_strlen (TREE_OPERAND (src, 1), only_value);
 316       len2 = c_strlen (TREE_OPERAND (src, 2), only_value);
 317       if (tree_int_cst_equal (len1, len2))
 318         return len1;
 319     }
 320
 321   if (TREE_CODE (src) == COMPOUND_EXPR
 322       && (only_value || !TREE_SIDE_EFFECTS (TREE_OPERAND (src, 0))))
 323     return c_strlen (TREE_OPERAND (src, 1), only_value);
 324
 325   src = string_constant (src, &offset_node);
 326   if (src == 0)
 327     return 0;
 328
 329   max = TREE_STRING_LENGTH (src) - 1;
 330   ptr = TREE_STRING_POINTER (src);
 331
 332   if (offset_node && TREE_CODE (offset_node) != INTEGER_CST)
 333     {
 334       /* If the string has an internal zero byte (e.g., "foo\0bar"), we can't
 335          compute the offset to the following null if we don't know where to
 336          start searching for it.  */
 337       int i;
 338
 339       for (i = 0; i < max; i++)
 340         if (ptr[i] == 0)
 341           return 0;
 342
 343       /* We don't know the starting offset, but we do know that the string
 344          has no internal zero bytes.  We can assume that the offset falls
 345          within the bounds of the string; otherwise, the programmer deserves
 346          what he gets.  Subtract the offset from the length of the string,
 347          and return that.  This would perhaps not be valid if we were dealing
 348          with named arrays in addition to literal string constants.  */
 349
 350       return size_diffop (size_int (max), offset_node);
 351     }
 352
 353   /* We have a known offset into the string.  Start searching there for
 354      a null character if we can represent it as a single HOST_WIDE_INT.  */
 355   if (offset_node == 0)
 356     offset = 0;
 357   else if (! host_integerp (offset_node, 0))
 358     offset = -1;
 359   else
 360     offset = tree_low_cst (offset_node, 0);
 361
 362   /* If the offset is known to be out of bounds, warn, and call strlen at
 363      runtime.  */
 364   if (offset < 0 || offset > max)
 365     {
 366       warning (0, "offset outside bounds of constant string");
 367       return 0;
 368     }
 369
 370   /* Use strlen to search for the first zero byte.  Since any strings
 371      constructed with build_string will have nulls appended, we win even
 372      if we get handed something like (char[4])"abcd".
 373
 374      Since OFFSET is our starting index into the string, no further
 375      calculation is needed.  */
 376   return ssize_int (strlen (ptr + offset));
 377 }
 378
 379 /* Return a char pointer for a C string if it is a string constant
 380    or sum of string constant and integer constant.  */
 381
 382 static const char *
 383 c_getstr (tree src)
 384 {
 385   tree offset_node;
 386
 387   src = string_constant (src, &offset_node);
 388   if (src == 0)
 389     return 0;
 390
 391   if (offset_node == 0)
 392     return TREE_STRING_POINTER (src);
 393   else if (!host_integerp (offset_node, 1)
 394            || compare_tree_int (offset_node, TREE_STRING_LENGTH (src) - 1) > 0)
 395     return 0;
 396
 397   return TREE_STRING_POINTER (src) + tree_low_cst (offset_node, 1);
 398 }
 399
 400 /* Return a CONST_INT or CONST_DOUBLE corresponding to target reading
 401    GET_MODE_BITSIZE (MODE) bits from string constant STR.  */
 402
 403 static rtx
 404 c_readstr (const char *str, enum machine_mode mode)
 405 {
 406   HOST_WIDE_INT c[2];
 407   HOST_WIDE_INT ch;
 408   unsigned int i, j;
 409
 410   gcc_assert (GET_MODE_CLASS (mode) == MODE_INT);
 411
 412   c[0] = 0;
 413   c[1] = 0;
 414   ch = 1;
 415   for (i = 0; i < GET_MODE_SIZE (mode); i++)
 416     {
 417       j = i;
 418       if (WORDS_BIG_ENDIAN)
 419         j = GET_MODE_SIZE (mode) - i - 1;
 420       if (BYTES_BIG_ENDIAN != WORDS_BIG_ENDIAN
 421           && GET_MODE_SIZE (mode) > UNITS_PER_WORD)
 422         j = j + UNITS_PER_WORD - 2 * (j % UNITS_PER_WORD) - 1;
 423       j *= BITS_PER_UNIT;
 424       gcc_assert (j <= 2 * HOST_BITS_PER_WIDE_INT);
 425
 426       if (ch)
 427         ch = (unsigned char) str[i];
 428       c[j / HOST_BITS_PER_WIDE_INT] |= ch << (j % HOST_BITS_PER_WIDE_INT);
 429     }
 430   return immed_double_const (c[0], c[1], mode);
 431 }
 432
 433 /* Cast a target constant CST to target CHAR and if that value fits into
 434    host char type, return zero and put that value into variable pointed to by
 435    P.  */
 436
 437 static int
 438 target_char_cast (tree cst, char *p)
 439 {
 440   unsigned HOST_WIDE_INT val, hostval;
 441
 442   if (!host_integerp (cst, 1)
 443       || CHAR_TYPE_SIZE > HOST_BITS_PER_WIDE_INT)
 444     return 1;
 445
 446   val = tree_low_cst (cst, 1);
 447   if (CHAR_TYPE_SIZE < HOST_BITS_PER_WIDE_INT)
 448     val &= (((unsigned HOST_WIDE_INT) 1) << CHAR_TYPE_SIZE) - 1;
 449
 450   hostval = val;
 451   if (HOST_BITS_PER_CHAR < HOST_BITS_PER_WIDE_INT)
 452     hostval &= (((unsigned HOST_WIDE_INT) 1) << HOST_BITS_PER_CHAR) - 1;
 453
 454   if (val != hostval)
 455     return 1;
 456
 457   *p = hostval;
 458   return 0;
 459 }
 460
 461 /* Similar to save_expr, but assumes that arbitrary code is not executed
 462    in between the multiple evaluations.  In particular, we assume that a
 463    non-addressable local variable will not be modified.  */
 464
 465 static tree
 466 builtin_save_expr (tree exp)
 467 {
 468   if (TREE_ADDRESSABLE (exp) == 0
 469       && (TREE_CODE (exp) == PARM_DECL
 470           || (TREE_CODE (exp) == VAR_DECL && !TREE_STATIC (exp))))
 471     return exp;
 472
 473   return save_expr (exp);
 474 }
 475
 476 /* Given TEM, a pointer to a stack frame, follow the dynamic chain COUNT
 477    times to get the address of either a higher stack frame, or a return
 478    address located within it (depending on FNDECL_CODE).  */
 479
 480 static rtx
 481 expand_builtin_return_addr (enum built_in_function fndecl_code, int count)
 482 {
 483   int i;
 484
 485 #ifdef INITIAL_FRAME_ADDRESS_RTX
 486   rtx tem = INITIAL_FRAME_ADDRESS_RTX;
 487 #else
 488   rtx tem;
 489
 490   /* For a zero count, we don't care what frame address we return, so frame
 491      pointer elimination is OK, and using the soft frame pointer is OK.
 492      For a non-zero count, we require a stable offset from the current frame
 493      pointer to the previous one, so we must use the hard frame pointer, and
 494      we must disable frame pointer elimination.  */
 495   if (count == 0)
 496     tem = frame_pointer_rtx;
 497   else
 498     {
 499       tem = hard_frame_pointer_rtx;
 500
 501       /* Tell reload not to eliminate the frame pointer.  */
 502       current_function_accesses_prior_frames = 1;
 503     }
 504 #endif
 505
 506   /* Some machines need special handling before we can access
 507      arbitrary frames.  For example, on the sparc, we must first flush
 508      all register windows to the stack.  */
 509 #ifdef SETUP_FRAME_ADDRESSES
 510   if (count > 0)
 511     SETUP_FRAME_ADDRESSES ();
 512 #endif
 513
 514   /* On the sparc, the return address is not in the frame, it is in a
 515      register.  There is no way to access it off of the current frame
 516      pointer, but it can be accessed off the previous frame pointer by
 517      reading the value from the register window save area.  */
 518 #ifdef RETURN_ADDR_IN_PREVIOUS_FRAME
 519   if (fndecl_code == BUILT_IN_RETURN_ADDRESS)
 520     count--;
 521 #endif
 522
 523   /* Scan back COUNT frames to the specified frame.  */
 524   for (i = 0; i < count; i++)
 525     {
 526       /* Assume the dynamic chain pointer is in the word that the
 527          frame address points to, unless otherwise specified.  */
 528 #ifdef DYNAMIC_CHAIN_ADDRESS
 529       tem = DYNAMIC_CHAIN_ADDRESS (tem);
 530 #endif
 531       tem = memory_address (Pmode, tem);
 532       tem = gen_frame_mem (Pmode, tem);
 533       tem = copy_to_reg (tem);
 534     }
 535
 536   /* For __builtin_frame_address, return what we've got.  */
 537   if (fndecl_code == BUILT_IN_FRAME_ADDRESS)
 538     return tem;
 539
 540   /* For __builtin_return_address, Get the return address from that
 541      frame.  */
 542 #ifdef RETURN_ADDR_RTX
 543   tem = RETURN_ADDR_RTX (count, tem);
 544 #else
 545   tem = memory_address (Pmode,
 546                         plus_constant (tem, GET_MODE_SIZE (Pmode)));
 547   tem = gen_frame_mem (Pmode, tem);
 548 #endif
 549   return tem;
 550 }
 551
 552 /* Alias set used for setjmp buffer.  */
 553 static HOST_WIDE_INT setjmp_alias_set = -1;
 554
 555 /* Construct the leading half of a __builtin_setjmp call.  Control will
 556    return to RECEIVER_LABEL.  This is used directly by sjlj exception
 557    handling code.  */
 558
 559 void
 560 expand_builtin_setjmp_setup (rtx buf_addr, rtx receiver_label)
 561 {
 562   enum machine_mode sa_mode = STACK_SAVEAREA_MODE (SAVE_NONLOCAL);
 563   rtx stack_save;
 564   rtx mem;
 565
 566   if (setjmp_alias_set == -1)
 567     setjmp_alias_set = new_alias_set ();
 568
 569   buf_addr = convert_memory_address (Pmode, buf_addr);
 570
 571   buf_addr = force_reg (Pmode, force_operand (buf_addr, NULL_RTX));
 572
 573   /* We store the frame pointer and the address of receiver_label in
 574      the buffer and use the rest of it for the stack save area, which
 575      is machine-dependent.  */
 576
 577   mem = gen_rtx_MEM (Pmode, buf_addr);
 578   set_mem_alias_set (mem, setjmp_alias_set);
 579   emit_move_insn (mem, targetm.builtin_setjmp_frame_value ());
 580
 581   mem = gen_rtx_MEM (Pmode, plus_constant (buf_addr, GET_MODE_SIZE (Pmode))),
 582   set_mem_alias_set (mem, setjmp_alias_set);
 583
 584   emit_move_insn (validize_mem (mem),
 585                   force_reg (Pmode, gen_rtx_LABEL_REF (Pmode, receiver_label)));
 586
 587   stack_save = gen_rtx_MEM (sa_mode,
 588                             plus_constant (buf_addr,
 589                                            2 * GET_MODE_SIZE (Pmode)));
 590   set_mem_alias_set (stack_save, setjmp_alias_set);
 591   emit_stack_save (SAVE_NONLOCAL, &stack_save, NULL_RTX);
 592
 593   /* If there is further processing to do, do it.  */
 594 #ifdef HAVE_builtin_setjmp_setup
 595   if (HAVE_builtin_setjmp_setup)
 596     emit_insn (gen_builtin_setjmp_setup (buf_addr));
 597 #endif
 598
 599   /* Tell optimize_save_area_alloca that extra work is going to
 600      need to go on during alloca.  */
 601   current_function_calls_setjmp = 1;
 602
 603   /* Set this so all the registers get saved in our frame; we need to be
 604      able to copy the saved values for any registers from frames we unwind.  */
 605   current_function_has_nonlocal_label = 1;
 606 }
 607
 608 /* Construct the trailing part of a __builtin_setjmp call.
 609    This is used directly by sjlj exception handling code.  */
 610
 611 void
 612 expand_builtin_setjmp_receiver (rtx receiver_label ATTRIBUTE_UNUSED)
 613 {
 614   /* Clobber the FP when we get here, so we have to make sure it's
 615      marked as used by this function.  */
 616   emit_insn (gen_rtx_USE (VOIDmode, hard_frame_pointer_rtx));
 617
 618   /* Mark the static chain as clobbered here so life information
 619      doesn't get messed up for it.  */
 620   emit_insn (gen_rtx_CLOBBER (VOIDmode, static_chain_rtx));
 621
 622   /* Now put in the code to restore the frame pointer, and argument
 623      pointer, if needed.  */
 624 #ifdef HAVE_nonlocal_goto
 625   if (! HAVE_nonlocal_goto)
 626 #endif
 627     emit_move_insn (virtual_stack_vars_rtx, hard_frame_pointer_rtx);
 628
 629 #if ARG_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
 630   if (fixed_regs[ARG_POINTER_REGNUM])
 631     {
 632 #ifdef ELIMINABLE_REGS
 633       size_t i;
 634       static const struct elims {const int from, to;} elim_regs[] = ELIMINABLE_REGS;
 635
 636       for (i = 0; i < ARRAY_SIZE (elim_regs); i++)
 637         if (elim_regs[i].from == ARG_POINTER_REGNUM
 638             && elim_regs[i].to == HARD_FRAME_POINTER_REGNUM)
 639           break;
 640
 641       if (i == ARRAY_SIZE (elim_regs))
 642 #endif
 643         {
 644           /* Now restore our arg pointer from the address at which it
 645              was saved in our stack frame.  */
 646           emit_move_insn (virtual_incoming_args_rtx,
 647                           copy_to_reg (get_arg_pointer_save_area (cfun)));
 648         }
 649     }
 650 #endif
 651
 652 #ifdef HAVE_builtin_setjmp_receiver
 653   if (HAVE_builtin_setjmp_receiver)
 654     emit_insn (gen_builtin_setjmp_receiver (receiver_label));
 655   else
 656 #endif
 657 #ifdef HAVE_nonlocal_goto_receiver
 658     if (HAVE_nonlocal_goto_receiver)
 659       emit_insn (gen_nonlocal_goto_receiver ());
 660     else
 661 #endif
 662       { /* Nothing */ }
 663
 664   /* @@@ This is a kludge.  Not all machine descriptions define a blockage
 665      insn, but we must not allow the code we just generated to be reordered
 666      by scheduling.  Specifically, the update of the frame pointer must
 667      happen immediately, not later.  So emit an ASM_INPUT to act as blockage
 668      insn.  */
 669   emit_insn (gen_rtx_ASM_INPUT (VOIDmode, ""));
 670 }
 671
 672 /* __builtin_setjmp is passed a pointer to an array of five words (not
 673    all will be used on all machines).  It operates similarly to the C
 674    library function of the same name, but is more efficient.  Much of
 675    the code below (and for longjmp) is copied from the handling of
 676    non-local gotos.
 677
 678    NOTE: This is intended for use by GNAT and the exception handling
 679    scheme in the compiler and will only work in the method used by
 680    them.  */
 681
 682 static rtx
 683 expand_builtin_setjmp (tree arglist, rtx target)
 684 {
 685   rtx buf_addr, next_lab, cont_lab;
 686
 687   if (!validate_arglist (arglist, POINTER_TYPE, VOID_TYPE))
 688     return NULL_RTX;
 689
 690   if (target == 0 || !REG_P (target)
 691       || REGNO (target) < FIRST_PSEUDO_REGISTER)
 692     target = gen_reg_rtx (TYPE_MODE (integer_type_node));
 693
 694   buf_addr = expand_expr (TREE_VALUE (arglist), NULL_RTX, VOIDmode, 0);
 695
 696   next_lab = gen_label_rtx ();
 697   cont_lab = gen_label_rtx ();
 698
 699   expand_builtin_setjmp_setup (buf_addr, next_lab);
 700
 701   /* Set TARGET to zero and branch to the continue label.  Use emit_jump to
 702      ensure that pending stack adjustments are flushed.  */
 703   emit_move_insn (target, const0_rtx);
 704   emit_jump (cont_lab);
 705
 706   emit_label (next_lab);
 707
 708   expand_builtin_setjmp_receiver (next_lab);
 709
 710   /* Set TARGET to one.  */
 711   emit_move_insn (target, const1_rtx);
 712   emit_label (cont_lab);
 713
 714   /* Tell flow about the strange goings on.  Putting `next_lab' on
 715      `nonlocal_goto_handler_labels' to indicates that function
 716      calls may traverse the arc back to this label.  */
 717
 718   current_function_has_nonlocal_label = 1;
 719   nonlocal_goto_handler_labels
 720     = gen_rtx_EXPR_LIST (VOIDmode, next_lab, nonlocal_goto_handler_labels);
 721
 722   return target;
 723 }
 724
 725 /* __builtin_longjmp is passed a pointer to an array of five words (not
 726    all will be used on all machines).  It operates similarly to the C
 727    library function of the same name, but is more efficient.  Much of
 728    the code below is copied from the handling of non-local gotos.
 729
 730    NOTE: This is intended for use by GNAT and the exception handling
 731    scheme in the compiler and will only work in the method used by
 732    them.  */
 733
 734 static void
 735 expand_builtin_longjmp (rtx buf_addr, rtx value)
 736 {
 737   rtx fp, lab, stack, insn, last;
 738   enum machine_mode sa_mode = STACK_SAVEAREA_MODE (SAVE_NONLOCAL);
 739
 740   if (setjmp_alias_set == -1)
 741     setjmp_alias_set = new_alias_set ();
 742
 743   buf_addr = convert_memory_address (Pmode, buf_addr);
 744
 745   buf_addr = force_reg (Pmode, buf_addr);
 746
 747   /* We used to store value in static_chain_rtx, but that fails if pointers
 748      are smaller than integers.  We instead require that the user must pass
 749      a second argument of 1, because that is what builtin_setjmp will
 750      return.  This also makes EH slightly more efficient, since we are no
 751      longer copying around a value that we don't care about.  */
 752   gcc_assert (value == const1_rtx);
 753
 754   last = get_last_insn ();
 755 #ifdef HAVE_builtin_longjmp
 756   if (HAVE_builtin_longjmp)
 757     emit_insn (gen_builtin_longjmp (buf_addr));
 758   else
 759 #endif
 760     {
 761       fp = gen_rtx_MEM (Pmode, buf_addr);
 762       lab = gen_rtx_MEM (Pmode, plus_constant (buf_addr,
 763                                                GET_MODE_SIZE (Pmode)));
 764
 765       stack = gen_rtx_MEM (sa_mode, plus_constant (buf_addr,
 766                                                    2 * GET_MODE_SIZE (Pmode)));
 767       set_mem_alias_set (fp, setjmp_alias_set);
 768       set_mem_alias_set (lab, setjmp_alias_set);
 769       set_mem_alias_set (stack, setjmp_alias_set);
 770
 771       /* Pick up FP, label, and SP from the block and jump.  This code is
 772          from expand_goto in stmt.c; see there for detailed comments.  */
 773 #if HAVE_nonlocal_goto
 774       if (HAVE_nonlocal_goto)
 775         /* We have to pass a value to the nonlocal_goto pattern that will
 776            get copied into the static_chain pointer, but it does not matter
 777            what that value is, because builtin_setjmp does not use it.  */
 778         emit_insn (gen_nonlocal_goto (value, lab, stack, fp));
 779       else
 780 #endif
 781         {
 782           lab = copy_to_reg (lab);
 783
 784           emit_insn (gen_rtx_CLOBBER (VOIDmode,
 785                                       gen_rtx_MEM (BLKmode,
 786                                                    gen_rtx_SCRATCH (VOIDmode))));
 787           emit_insn (gen_rtx_CLOBBER (VOIDmode,
 788                                       gen_rtx_MEM (BLKmode,
 789                                                    hard_frame_pointer_rtx)));
 790
 791           emit_move_insn (hard_frame_pointer_rtx, fp);
 792           emit_stack_restore (SAVE_NONLOCAL, stack, NULL_RTX);
 793
 794           emit_insn (gen_rtx_USE (VOIDmode, hard_frame_pointer_rtx));
 795           emit_insn (gen_rtx_USE (VOIDmode, stack_pointer_rtx));
 796           emit_indirect_jump (lab);
 797         }
 798     }
 799
 800   /* Search backwards and mark the jump insn as a non-local goto.
 801      Note that this precludes the use of __builtin_longjmp to a
 802      __builtin_setjmp target in the same function.  However, we've
 803      already cautioned the user that these functions are for
 804      internal exception handling use only.  */
 805   for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
 806     {
 807       gcc_assert (insn != last);
 808
 809       if (JUMP_P (insn))
 810         {
 811           REG_NOTES (insn) = alloc_EXPR_LIST (REG_NON_LOCAL_GOTO, const0_rtx,
 812                                               REG_NOTES (insn));
 813           break;
 814         }
 815       else if (CALL_P (insn))
 816         break;
 817     }
 818 }
 819
 820 /* Expand a call to __builtin_nonlocal_goto.  We're passed the target label
 821    and the address of the save area.  */
 822
 823 static rtx
 824 expand_builtin_nonlocal_goto (tree arglist)
 825 {
 826   tree t_label, t_save_area;
 827   rtx r_label, r_save_area, r_fp, r_sp, insn;
 828
 829   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
 830     return NULL_RTX;
 831
 832   t_label = TREE_VALUE (arglist);
 833   arglist = TREE_CHAIN (arglist);
 834   t_save_area = TREE_VALUE (arglist);
 835
 836   r_label = expand_expr (t_label, NULL_RTX, VOIDmode, 0);
 837   r_label = convert_memory_address (Pmode, r_label);
 838   r_save_area = expand_expr (t_save_area, NULL_RTX, VOIDmode, 0);
 839   r_save_area = convert_memory_address (Pmode, r_save_area);
 840   r_fp = gen_rtx_MEM (Pmode, r_save_area);
 841   r_sp = gen_rtx_MEM (STACK_SAVEAREA_MODE (SAVE_NONLOCAL),
 842                       plus_constant (r_save_area, GET_MODE_SIZE (Pmode)));
 843
 844   current_function_has_nonlocal_goto = 1;
 845
 846 #if HAVE_nonlocal_goto
 847   /* ??? We no longer need to pass the static chain value, afaik.  */
 848   if (HAVE_nonlocal_goto)
 849     emit_insn (gen_nonlocal_goto (const0_rtx, r_label, r_sp, r_fp));
 850   else
 851 #endif
 852     {
 853       r_label = copy_to_reg (r_label);
 854
 855       emit_insn (gen_rtx_CLOBBER (VOIDmode,
 856                                   gen_rtx_MEM (BLKmode,
 857                                                gen_rtx_SCRATCH (VOIDmode))));
 858
 859       emit_insn (gen_rtx_CLOBBER (VOIDmode,
 860                                   gen_rtx_MEM (BLKmode,
 861                                                hard_frame_pointer_rtx)));
 862
 863       /* Restore frame pointer for containing function.
 864          This sets the actual hard register used for the frame pointer
 865          to the location of the function's incoming static chain info.
 866          The non-local goto handler will then adjust it to contain the
 867          proper value and reload the argument pointer, if needed.  */
 868       emit_move_insn (hard_frame_pointer_rtx, r_fp);
 869       emit_stack_restore (SAVE_NONLOCAL, r_sp, NULL_RTX);
 870
 871       /* USE of hard_frame_pointer_rtx added for consistency;
 872          not clear if really needed.  */
 873       emit_insn (gen_rtx_USE (VOIDmode, hard_frame_pointer_rtx));
 874       emit_insn (gen_rtx_USE (VOIDmode, stack_pointer_rtx));
 875       emit_indirect_jump (r_label);
 876     }
 877
 878   /* Search backwards to the jump insn and mark it as a
 879      non-local goto.  */
 880   for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
 881     {
 882       if (JUMP_P (insn))
 883         {
 884           REG_NOTES (insn) = alloc_EXPR_LIST (REG_NON_LOCAL_GOTO,
 885                                               const0_rtx, REG_NOTES (insn));
 886           break;
 887         }
 888       else if (CALL_P (insn))
 889         break;
 890     }
 891
 892   return const0_rtx;
 893 }
 894
 895 /* __builtin_update_setjmp_buf is passed a pointer to an array of five words
 896    (not all will be used on all machines) that was passed to __builtin_setjmp.
 897    It updates the stack pointer in that block to correspond to the current
 898    stack pointer.  */
 899
 900 static void
 901 expand_builtin_update_setjmp_buf (rtx buf_addr)
 902 {
 903   enum machine_mode sa_mode = Pmode;
 904   rtx stack_save;
 905
 906
 907 #ifdef HAVE_save_stack_nonlocal
 908   if (HAVE_save_stack_nonlocal)
 909     sa_mode = insn_data[(int) CODE_FOR_save_stack_nonlocal].operand[0].mode;
 910 #endif
 911 #ifdef STACK_SAVEAREA_MODE
 912   sa_mode = STACK_SAVEAREA_MODE (SAVE_NONLOCAL);
 913 #endif
 914
 915   stack_save
 916     = gen_rtx_MEM (sa_mode,
 917                    memory_address
 918                    (sa_mode,
 919                     plus_constant (buf_addr, 2 * GET_MODE_SIZE (Pmode))));
 920
 921 #ifdef HAVE_setjmp
 922   if (HAVE_setjmp)
 923     emit_insn (gen_setjmp ());
 924 #endif
 925
 926   emit_stack_save (SAVE_NONLOCAL, &stack_save, NULL_RTX);
 927 }
 928
 929 /* Expand a call to __builtin_prefetch.  For a target that does not support
 930    data prefetch, evaluate the memory address argument in case it has side
 931    effects.  */
 932
 933 static void
 934 expand_builtin_prefetch (tree arglist)
 935 {
 936   tree arg0, arg1, arg2;
 937   rtx op0, op1, op2;
 938
 939   if (!validate_arglist (arglist, POINTER_TYPE, 0))
 940     return;
 941
 942   arg0 = TREE_VALUE (arglist);
 943   /* Arguments 1 and 2 are optional; argument 1 (read/write) defaults to
 944      zero (read) and argument 2 (locality) defaults to 3 (high degree of
 945      locality).  */
 946   if (TREE_CHAIN (arglist))
 947     {
 948       arg1 = TREE_VALUE (TREE_CHAIN (arglist));
 949       if (TREE_CHAIN (TREE_CHAIN (arglist)))
 950         arg2 = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
 951       else
 952         arg2 = build_int_cst (NULL_TREE, 3);
 953     }
 954   else
 955     {
 956       arg1 = integer_zero_node;
 957       arg2 = build_int_cst (NULL_TREE, 3);
 958     }
 959
 960   /* Argument 0 is an address.  */
 961   op0 = expand_expr (arg0, NULL_RTX, Pmode, EXPAND_NORMAL);
 962
 963   /* Argument 1 (read/write flag) must be a compile-time constant int.  */
 964   if (TREE_CODE (arg1) != INTEGER_CST)
 965     {
 966       error ("second argument to %<__builtin_prefetch%> must be a constant");
 967       arg1 = integer_zero_node;
 968     }
 969   op1 = expand_expr (arg1, NULL_RTX, VOIDmode, 0);
 970   /* Argument 1 must be either zero or one.  */
 971   if (INTVAL (op1) != 0 && INTVAL (op1) != 1)
 972     {
 973       warning (0, "invalid second argument to %<__builtin_prefetch%>;"
 974                " using zero");
 975       op1 = const0_rtx;
 976     }
 977
 978   /* Argument 2 (locality) must be a compile-time constant int.  */
 979   if (TREE_CODE (arg2) != INTEGER_CST)
 980     {
 981       error ("third argument to %<__builtin_prefetch%> must be a constant");
 982       arg2 = integer_zero_node;
 983     }
 984   op2 = expand_expr (arg2, NULL_RTX, VOIDmode, 0);
 985   /* Argument 2 must be 0, 1, 2, or 3.  */
 986   if (INTVAL (op2) < 0 || INTVAL (op2) > 3)
 987     {
 988       warning (0, "invalid third argument to %<__builtin_prefetch%>; using zero");
 989       op2 = const0_rtx;
 990     }
 991
 992 #ifdef HAVE_prefetch
 993   if (HAVE_prefetch)
 994     {
 995       if ((! (*insn_data[(int) CODE_FOR_prefetch].operand[0].predicate)
 996              (op0,
 997               insn_data[(int) CODE_FOR_prefetch].operand[0].mode))
 998           || (GET_MODE (op0) != Pmode))
 999         {
1000           op0 = convert_memory_address (Pmode, op0);
1001           op0 = force_reg (Pmode, op0);
1002         }
1003       emit_insn (gen_prefetch (op0, op1, op2));
1004     }
1005 #endif
1006
1007   /* Don't do anything with direct references to volatile memory, but
1008      generate code to handle other side effects.  */
1009   if (!MEM_P (op0) && side_effects_p (op0))
1010     emit_insn (op0);
1011 }
1012
1013 /* Get a MEM rtx for expression EXP which is the address of an operand
1014    to be used in a string instruction (cmpstrsi, movmemsi, ..).  LEN is
1015    the maximum length of the block of memory that might be accessed or
1016    NULL if unknown.  */
1017
1018 static rtx
1019 get_memory_rtx (tree exp, tree len)
1020 {
1021   rtx addr = expand_expr (exp, NULL_RTX, ptr_mode, EXPAND_NORMAL);
1022   rtx mem = gen_rtx_MEM (BLKmode, memory_address (BLKmode, addr));
1023
1024   /* Get an expression we can use to find the attributes to assign to MEM.
1025      If it is an ADDR_EXPR, use the operand.  Otherwise, dereference it if
1026      we can.  First remove any nops.  */
1027   while ((TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR
1028           || TREE_CODE (exp) == NON_LVALUE_EXPR)
1029          && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
1030     exp = TREE_OPERAND (exp, 0);
1031
1032   if (TREE_CODE (exp) == ADDR_EXPR)
1033     exp = TREE_OPERAND (exp, 0);
1034   else if (POINTER_TYPE_P (TREE_TYPE (exp)))
1035     exp = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (exp)), exp);
1036   else
1037     exp = NULL;
1038
1039   /* Honor attributes derived from exp, except for the alias set
1040      (as builtin stringops may alias with anything) and the size
1041      (as stringops may access multiple array elements).  */
1042   if (exp)
1043     {
1044       set_mem_attributes (mem, exp, 0);
1045
1046       /* Allow the string and memory builtins to overflow from one
1047          field into another, see http://gcc.gnu.org/PR23561.
1048          Thus avoid COMPONENT_REFs in MEM_EXPR unless we know the whole
1049          memory accessed by the string or memory builtin will fit
1050          within the field.  */
1051       if (MEM_EXPR (mem) && TREE_CODE (MEM_EXPR (mem)) == COMPONENT_REF)
1052         {
1053           tree mem_expr = MEM_EXPR (mem);
1054           HOST_WIDE_INT offset = -1, length = -1;
1055           tree inner = exp;
1056
1057           while (TREE_CODE (inner) == ARRAY_REF
1058                  || TREE_CODE (inner) == NOP_EXPR
1059                  || TREE_CODE (inner) == CONVERT_EXPR
1060                  || TREE_CODE (inner) == NON_LVALUE_EXPR
1061                  || TREE_CODE (inner) == VIEW_CONVERT_EXPR
1062                  || TREE_CODE (inner) == SAVE_EXPR)
1063             inner = TREE_OPERAND (inner, 0);
1064
1065           gcc_assert (TREE_CODE (inner) == COMPONENT_REF);
1066
1067           if (MEM_OFFSET (mem)
1068               && GET_CODE (MEM_OFFSET (mem)) == CONST_INT)
1069             offset = INTVAL (MEM_OFFSET (mem));
1070
1071           if (offset >= 0 && len && host_integerp (len, 0))
1072             length = tree_low_cst (len, 0);
1073
1074           while (TREE_CODE (inner) == COMPONENT_REF)
1075             {
1076               tree field = TREE_OPERAND (inner, 1);
1077               gcc_assert (! DECL_BIT_FIELD (field));
1078               gcc_assert (TREE_CODE (mem_expr) == COMPONENT_REF);
1079               gcc_assert (field == TREE_OPERAND (mem_expr, 1));
1080
1081               if (length >= 0
1082                   && TYPE_SIZE_UNIT (TREE_TYPE (inner))
1083                   && host_integerp (TYPE_SIZE_UNIT (TREE_TYPE (inner)), 0))
1084                 {
1085                   HOST_WIDE_INT size
1086                     = tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (inner)), 0);
1087                   /* If we can prove the memory starting at XEXP (mem, 0)
1088                      and ending at XEXP (mem, 0) + LENGTH will fit into
1089                      this field, we can keep that COMPONENT_REF in MEM_EXPR.  */
1090                   if (offset <= size
1091                       && length <= size
1092                       && offset + length <= size)
1093                     break;
1094                 }
1095
1096               if (offset >= 0
1097                   && host_integerp (DECL_FIELD_OFFSET (field), 0))
1098                 offset += tree_low_cst (DECL_FIELD_OFFSET (field), 0)
1099                           + tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1)
1100                             / BITS_PER_UNIT;
1101               else
1102                 {
1103                   offset = -1;
1104                   length = -1;
1105                 }
1106
1107               mem_expr = TREE_OPERAND (mem_expr, 0);
1108               inner = TREE_OPERAND (inner, 0);
1109             }
1110
1111           if (mem_expr == NULL)
1112             offset = -1;
1113           if (mem_expr != MEM_EXPR (mem))
1114             {
1115               set_mem_expr (mem, mem_expr);
1116               set_mem_offset (mem, offset >= 0 ? GEN_INT (offset) : NULL_RTX);
1117             }
1118         }
1119       set_mem_alias_set (mem, 0);
1120       set_mem_size (mem, NULL_RTX);
1121     }
1122
1123   return mem;
1124 }
1125 \f
1126 /* Built-in functions to perform an untyped call and return.  */
1127
1128 /* For each register that may be used for calling a function, this
1129    gives a mode used to copy the register's value.  VOIDmode indicates
1130    the register is not used for calling a function.  If the machine
1131    has register windows, this gives only the outbound registers.
1132    INCOMING_REGNO gives the corresponding inbound register.  */
1133 static enum machine_mode apply_args_mode[FIRST_PSEUDO_REGISTER];
1134
1135 /* For each register that may be used for returning values, this gives
1136    a mode used to copy the register's value.  VOIDmode indicates the
1137    register is not used for returning values.  If the machine has
1138    register windows, this gives only the outbound registers.
1139    INCOMING_REGNO gives the corresponding inbound register.  */
1140 static enum machine_mode apply_result_mode[FIRST_PSEUDO_REGISTER];
1141
1142 /* For each register that may be used for calling a function, this
1143    gives the offset of that register into the block returned by
1144    __builtin_apply_args.  0 indicates that the register is not
1145    used for calling a function.  */
1146 static int apply_args_reg_offset[FIRST_PSEUDO_REGISTER];
1147
1148 /* Return the size required for the block returned by __builtin_apply_args,
1149    and initialize apply_args_mode.  */
1150
1151 static int
1152 apply_args_size (void)
1153 {
1154   static int size = -1;
1155   int align;
1156   unsigned int regno;
1157   enum machine_mode mode;
1158
1159   /* The values computed by this function never change.  */
1160   if (size < 0)
1161     {
1162       /* The first value is the incoming arg-pointer.  */
1163       size = GET_MODE_SIZE (Pmode);
1164
1165       /* The second value is the structure value address unless this is
1166          passed as an "invisible" first argument.  */
1167       if (targetm.calls.struct_value_rtx (cfun ? TREE_TYPE (cfun->decl) : 0, 0))
1168         size += GET_MODE_SIZE (Pmode);
1169
1170       for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
1171         if (FUNCTION_ARG_REGNO_P (regno))
1172           {
1173             mode = reg_raw_mode[regno];
1174
1175             gcc_assert (mode != VOIDmode);
1176
1177             align = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
1178             if (size % align != 0)
1179               size = CEIL (size, align) * align;
1180             apply_args_reg_offset[regno] = size;
1181             size += GET_MODE_SIZE (mode);
1182             apply_args_mode[regno] = mode;
1183           }
1184         else
1185           {
1186             apply_args_mode[regno] = VOIDmode;
1187             apply_args_reg_offset[regno] = 0;
1188           }
1189     }
1190   return size;
1191 }
1192
1193 /* Return the size required for the block returned by __builtin_apply,
1194    and initialize apply_result_mode.  */
1195
1196 static int
1197 apply_result_size (void)
1198 {
1199   static int size = -1;
1200   int align, regno;
1201   enum machine_mode mode;
1202
1203   /* The values computed by this function never change.  */
1204   if (size < 0)
1205     {
1206       size = 0;
1207
1208       for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
1209         if (FUNCTION_VALUE_REGNO_P (regno))
1210           {
1211             mode = reg_raw_mode[regno];
1212
1213             gcc_assert (mode != VOIDmode);
1214
1215             align = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
1216             if (size % align != 0)
1217               size = CEIL (size, align) * align;
1218             size += GET_MODE_SIZE (mode);
1219             apply_result_mode[regno] = mode;
1220           }
1221         else
1222           apply_result_mode[regno] = VOIDmode;
1223
1224       /* Allow targets that use untyped_call and untyped_return to override
1225          the size so that machine-specific information can be stored here.  */
1226 #ifdef APPLY_RESULT_SIZE
1227       size = APPLY_RESULT_SIZE;
1228 #endif
1229     }
1230   return size;
1231 }
1232
1233 #if defined (HAVE_untyped_call) || defined (HAVE_untyped_return)
1234 /* Create a vector describing the result block RESULT.  If SAVEP is true,
1235    the result block is used to save the values; otherwise it is used to
1236    restore the values.  */
1237
1238 static rtx
1239 result_vector (int savep, rtx result)
1240 {
1241   int regno, size, align, nelts;
1242   enum machine_mode mode;
1243   rtx reg, mem;
1244   rtx *savevec = alloca (FIRST_PSEUDO_REGISTER * sizeof (rtx));
1245
1246   size = nelts = 0;
1247   for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
1248     if ((mode = apply_result_mode[regno]) != VOIDmode)
1249       {
1250         align = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
1251         if (size % align != 0)
1252           size = CEIL (size, align) * align;
1253         reg = gen_rtx_REG (mode, savep ? regno : INCOMING_REGNO (regno));
1254         mem = adjust_address (result, mode, size);
1255         savevec[nelts++] = (savep
1256                             ? gen_rtx_SET (VOIDmode, mem, reg)
1257                             : gen_rtx_SET (VOIDmode, reg, mem));
1258         size += GET_MODE_SIZE (mode);
1259       }
1260   return gen_rtx_PARALLEL (VOIDmode, gen_rtvec_v (nelts, savevec));
1261 }
1262 #endif /* HAVE_untyped_call or HAVE_untyped_return */
1263
1264 /* Save the state required to perform an untyped call with the same
1265    arguments as were passed to the current function.  */
1266
1267 static rtx
1268 expand_builtin_apply_args_1 (void)
1269 {
1270   rtx registers, tem;
1271   int size, align, regno;
1272   enum machine_mode mode;
1273   rtx struct_incoming_value = targetm.calls.struct_value_rtx (cfun ? TREE_TYPE (cfun->decl) : 0, 1);
1274
1275   /* Create a block where the arg-pointer, structure value address,
1276      and argument registers can be saved.  */
1277   registers = assign_stack_local (BLKmode, apply_args_size (), -1);
1278
1279   /* Walk past the arg-pointer and structure value address.  */
1280   size = GET_MODE_SIZE (Pmode);
1281   if (targetm.calls.struct_value_rtx (cfun ? TREE_TYPE (cfun->decl) : 0, 0))
1282     size += GET_MODE_SIZE (Pmode);
1283
1284   /* Save each register used in calling a function to the block.  */
1285   for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
1286     if ((mode = apply_args_mode[regno]) != VOIDmode)
1287       {
1288         align = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
1289         if (size % align != 0)
1290           size = CEIL (size, align) * align;
1291
1292         tem = gen_rtx_REG (mode, INCOMING_REGNO (regno));
1293
1294         emit_move_insn (adjust_address (registers, mode, size), tem);
1295         size += GET_MODE_SIZE (mode);
1296       }
1297
1298   /* Save the arg pointer to the block.  */
1299   tem = copy_to_reg (virtual_incoming_args_rtx);
1300 #ifdef STACK_GROWS_DOWNWARD
1301   /* We need the pointer as the caller actually passed them to us, not
1302      as we might have pretended they were passed.  Make sure it's a valid
1303      operand, as emit_move_insn isn't expected to handle a PLUS.  */
1304   tem
1305     = force_operand (plus_constant (tem, current_function_pretend_args_size),
1306                      NULL_RTX);
1307 #endif
1308   emit_move_insn (adjust_address (registers, Pmode, 0), tem);
1309
1310   size = GET_MODE_SIZE (Pmode);
1311
1312   /* Save the structure value address unless this is passed as an
1313      "invisible" first argument.  */
1314   if (struct_incoming_value)
1315     {
1316       emit_move_insn (adjust_address (registers, Pmode, size),
1317                       copy_to_reg (struct_incoming_value));
1318       size += GET_MODE_SIZE (Pmode);
1319     }
1320
1321   /* Return the address of the block.  */
1322   return copy_addr_to_reg (XEXP (registers, 0));
1323 }
1324
1325 /* __builtin_apply_args returns block of memory allocated on
1326    the stack into which is stored the arg pointer, structure
1327    value address, static chain, and all the registers that might
1328    possibly be used in performing a function call.  The code is
1329    moved to the start of the function so the incoming values are
1330    saved.  */
1331
1332 static rtx
1333 expand_builtin_apply_args (void)
1334 {
1335   /* Don't do __builtin_apply_args more than once in a function.
1336      Save the result of the first call and reuse it.  */
1337   if (apply_args_value != 0)
1338     return apply_args_value;
1339   {
1340     /* When this function is called, it means that registers must be
1341        saved on entry to this function.  So we migrate the
1342        call to the first insn of this function.  */
1343     rtx temp;
1344     rtx seq;
1345
1346     start_sequence ();
1347     temp = expand_builtin_apply_args_1 ();
1348     seq = get_insns ();
1349     end_sequence ();
1350
1351     apply_args_value = temp;
1352
1353     /* Put the insns after the NOTE that starts the function.
1354        If this is inside a start_sequence, make the outer-level insn
1355        chain current, so the code is placed at the start of the
1356        function.  */
1357     push_topmost_sequence ();
1358     emit_insn_before (seq, NEXT_INSN (entry_of_function ()));
1359     pop_topmost_sequence ();
1360     return temp;
1361   }
1362 }
1363
1364 /* Perform an untyped call and save the state required to perform an
1365    untyped return of whatever value was returned by the given function.  */
1366
1367 static rtx
1368 expand_builtin_apply (rtx function, rtx arguments, rtx argsize)
1369 {
1370   int size, align, regno;
1371   enum machine_mode mode;
1372   rtx incoming_args, result, reg, dest, src, call_insn;
1373   rtx old_stack_level = 0;
1374   rtx call_fusage = 0;
1375   rtx struct_value = targetm.calls.struct_value_rtx (cfun ? TREE_TYPE (cfun->decl) : 0, 0);
1376
1377   arguments = convert_memory_address (Pmode, arguments);
1378
1379   /* Create a block where the return registers can be saved.  */
1380   result = assign_stack_local (BLKmode, apply_result_size (), -1);
1381
1382   /* Fetch the arg pointer from the ARGUMENTS block.  */
1383   incoming_args = gen_reg_rtx (Pmode);
1384   emit_move_insn (incoming_args, gen_rtx_MEM (Pmode, arguments));
1385 #ifndef STACK_GROWS_DOWNWARD
1386   incoming_args = expand_simple_binop (Pmode, MINUS, incoming_args, argsize,
1387                                        incoming_args, 0, OPTAB_LIB_WIDEN);
1388 #endif
1389
1390   /* Push a new argument block and copy the arguments.  Do not allow
1391      the (potential) memcpy call below to interfere with our stack
1392      manipulations.  */
1393   do_pending_stack_adjust ();
1394   NO_DEFER_POP;
1395
1396   /* Save the stack with nonlocal if available.  */
1397 #ifdef HAVE_save_stack_nonlocal
1398   if (HAVE_save_stack_nonlocal)
1399     emit_stack_save (SAVE_NONLOCAL, &old_stack_level, NULL_RTX);
1400   else
1401 #endif
1402     emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1403
1404   /* Allocate a block of memory onto the stack and copy the memory
1405      arguments to the outgoing arguments address.  */
1406   allocate_dynamic_stack_space (argsize, 0, BITS_PER_UNIT);
1407   dest = virtual_outgoing_args_rtx;
1408 #ifndef STACK_GROWS_DOWNWARD
1409   if (GET_CODE (argsize) == CONST_INT)
1410     dest = plus_constant (dest, -INTVAL (argsize));
1411   else
1412     dest = gen_rtx_PLUS (Pmode, dest, negate_rtx (Pmode, argsize));
1413 #endif
1414   dest = gen_rtx_MEM (BLKmode, dest);
1415   set_mem_align (dest, PARM_BOUNDARY);
1416   src = gen_rtx_MEM (BLKmode, incoming_args);
1417   set_mem_align (src, PARM_BOUNDARY);
1418   emit_block_move (dest, src, argsize, BLOCK_OP_NORMAL);
1419
1420   /* Refer to the argument block.  */
1421   apply_args_size ();
1422   arguments = gen_rtx_MEM (BLKmode, arguments);
1423   set_mem_align (arguments, PARM_BOUNDARY);
1424
1425   /* Walk past the arg-pointer and structure value address.  */
1426   size = GET_MODE_SIZE (Pmode);
1427   if (struct_value)
1428     size += GET_MODE_SIZE (Pmode);
1429
1430   /* Restore each of the registers previously saved.  Make USE insns
1431      for each of these registers for use in making the call.  */
1432   for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
1433     if ((mode = apply_args_mode[regno]) != VOIDmode)
1434       {
1435         align = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
1436         if (size % align != 0)
1437           size = CEIL (size, align) * align;
1438         reg = gen_rtx_REG (mode, regno);
1439         emit_move_insn (reg, adjust_address (arguments, mode, size));
1440         use_reg (&call_fusage, reg);
1441         size += GET_MODE_SIZE (mode);
1442       }
1443
1444   /* Restore the structure value address unless this is passed as an
1445      "invisible" first argument.  */
1446   size = GET_MODE_SIZE (Pmode);
1447   if (struct_value)
1448     {
1449       rtx value = gen_reg_rtx (Pmode);
1450       emit_move_insn (value, adjust_address (arguments, Pmode, size));
1451       emit_move_insn (struct_value, value);
1452       if (REG_P (struct_value))
1453         use_reg (&call_fusage, struct_value);
1454       size += GET_MODE_SIZE (Pmode);
1455     }
1456
1457   /* All arguments and registers used for the call are set up by now!  */
1458   function = prepare_call_address (function, NULL, &call_fusage, 0, 0);
1459
1460   /* Ensure address is valid.  SYMBOL_REF is already valid, so no need,
1461      and we don't want to load it into a register as an optimization,
1462      because prepare_call_address already did it if it should be done.  */
1463   if (GET_CODE (function) != SYMBOL_REF)
1464     function = memory_address (FUNCTION_MODE, function);
1465
1466   /* Generate the actual call instruction and save the return value.  */
1467 #ifdef HAVE_untyped_call
1468   if (HAVE_untyped_call)
1469     emit_call_insn (gen_untyped_call (gen_rtx_MEM (FUNCTION_MODE, function),
1470                                       result, result_vector (1, result)));
1471   else
1472 #endif
1473 #ifdef HAVE_call_value
1474   if (HAVE_call_value)
1475     {
1476       rtx valreg = 0;
1477
1478       /* Locate the unique return register.  It is not possible to
1479          express a call that sets more than one return register using
1480          call_value; use untyped_call for that.  In fact, untyped_call
1481          only needs to save the return registers in the given block.  */
1482       for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
1483         if ((mode = apply_result_mode[regno]) != VOIDmode)
1484           {
1485             gcc_assert (!valreg); /* HAVE_untyped_call required.  */
1486
1487             valreg = gen_rtx_REG (mode, regno);
1488           }
1489
1490       emit_call_insn (GEN_CALL_VALUE (valreg,
1491                                       gen_rtx_MEM (FUNCTION_MODE, function),
1492                                       const0_rtx, NULL_RTX, const0_rtx));
1493
1494       emit_move_insn (adjust_address (result, GET_MODE (valreg), 0), valreg);
1495     }
1496   else
1497 #endif
1498     gcc_unreachable ();
1499
1500   /* Find the CALL insn we just emitted, and attach the register usage
1501      information.  */
1502   call_insn = last_call_insn ();
1503   add_function_usage_to (call_insn, call_fusage);
1504
1505   /* Restore the stack.  */
1506 #ifdef HAVE_save_stack_nonlocal
1507   if (HAVE_save_stack_nonlocal)
1508     emit_stack_restore (SAVE_NONLOCAL, old_stack_level, NULL_RTX);
1509   else
1510 #endif
1511     emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1512
1513   OK_DEFER_POP;
1514
1515   /* Return the address of the result block.  */
1516   result = copy_addr_to_reg (XEXP (result, 0));
1517   return convert_memory_address (ptr_mode, result);
1518 }
1519
1520 /* Perform an untyped return.  */
1521
1522 static void
1523 expand_builtin_return (rtx result)
1524 {
1525   int size, align, regno;
1526   enum machine_mode mode;
1527   rtx reg;
1528   rtx call_fusage = 0;
1529
1530   result = convert_memory_address (Pmode, result);
1531
1532   apply_result_size ();
1533   result = gen_rtx_MEM (BLKmode, result);
1534
1535 #ifdef HAVE_untyped_return
1536   if (HAVE_untyped_return)
1537     {
1538       emit_jump_insn (gen_untyped_return (result, result_vector (0, result)));
1539       emit_barrier ();
1540       return;
1541     }
1542 #endif
1543
1544   /* Restore the return value and note that each value is used.  */
1545   size = 0;
1546   for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
1547     if ((mode = apply_result_mode[regno]) != VOIDmode)
1548       {
1549         align = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
1550         if (size % align != 0)
1551           size = CEIL (size, align) * align;
1552         reg = gen_rtx_REG (mode, INCOMING_REGNO (regno));
1553         emit_move_insn (reg, adjust_address (result, mode, size));
1554
1555         push_to_sequence (call_fusage);
1556         emit_insn (gen_rtx_USE (VOIDmode, reg));
1557         call_fusage = get_insns ();
1558         end_sequence ();
1559         size += GET_MODE_SIZE (mode);
1560       }
1561
1562   /* Put the USE insns before the return.  */
1563   emit_insn (call_fusage);
1564
1565   /* Return whatever values was restored by jumping directly to the end
1566      of the function.  */
1567   expand_naked_return ();
1568 }
1569
1570 /* Used by expand_builtin_classify_type and fold_builtin_classify_type.  */
1571
1572 static enum type_class
1573 type_to_class (tree type)
1574 {
1575   switch (TREE_CODE (type))
1576     {
1577     case VOID_TYPE:        return void_type_class;
1578     case INTEGER_TYPE:     return integer_type_class;
1579     case CHAR_TYPE:        return char_type_class;
1580     case ENUMERAL_TYPE:    return enumeral_type_class;
1581     case BOOLEAN_TYPE:     return boolean_type_class;
1582     case POINTER_TYPE:     return pointer_type_class;
1583     case REFERENCE_TYPE:   return reference_type_class;
1584     case OFFSET_TYPE:      return offset_type_class;
1585     case REAL_TYPE:        return real_type_class;
1586     case COMPLEX_TYPE:     return complex_type_class;
1587     case FUNCTION_TYPE:    return function_type_class;
1588     case METHOD_TYPE:      return method_type_class;
1589     case RECORD_TYPE:      return record_type_class;
1590     case UNION_TYPE:
1591     case QUAL_UNION_TYPE:  return union_type_class;
1592     case ARRAY_TYPE:       return (TYPE_STRING_FLAG (type)
1593                                    ? string_type_class : array_type_class);
1594     case LANG_TYPE:        return lang_type_class;
1595     default:               return no_type_class;
1596     }
1597 }
1598
1599 /* Expand a call to __builtin_classify_type with arguments found in
1600    ARGLIST.  */
1601
1602 static rtx
1603 expand_builtin_classify_type (tree arglist)
1604 {
1605   if (arglist != 0)
1606     return GEN_INT (type_to_class (TREE_TYPE (TREE_VALUE (arglist))));
1607   return GEN_INT (no_type_class);
1608 }
1609
1610 /* This helper macro, meant to be used in mathfn_built_in below,
1611    determines which among a set of three builtin math functions is
1612    appropriate for a given type mode.  The `F' and `L' cases are
1613    automatically generated from the `double' case.  */
1614 #define CASE_MATHFN(BUILT_IN_MATHFN) \
1615   case BUILT_IN_MATHFN: case BUILT_IN_MATHFN##F: case BUILT_IN_MATHFN##L: \
1616   fcode = BUILT_IN_MATHFN; fcodef = BUILT_IN_MATHFN##F ; \
1617   fcodel = BUILT_IN_MATHFN##L ; break;
1618
1619 /* Return mathematic function equivalent to FN but operating directly
1620    on TYPE, if available.  If we can't do the conversion, return zero.  */
1621 tree
1622 mathfn_built_in (tree type, enum built_in_function fn)
1623 {
1624   enum built_in_function fcode, fcodef, fcodel;
1625
1626   switch (fn)
1627     {
1628       CASE_MATHFN (BUILT_IN_ACOS)
1629       CASE_MATHFN (BUILT_IN_ACOSH)
1630       CASE_MATHFN (BUILT_IN_ASIN)
1631       CASE_MATHFN (BUILT_IN_ASINH)
1632       CASE_MATHFN (BUILT_IN_ATAN)
1633       CASE_MATHFN (BUILT_IN_ATAN2)
1634       CASE_MATHFN (BUILT_IN_ATANH)
1635       CASE_MATHFN (BUILT_IN_CBRT)
1636       CASE_MATHFN (BUILT_IN_CEIL)
1637       CASE_MATHFN (BUILT_IN_COPYSIGN)
1638       CASE_MATHFN (BUILT_IN_COS)
1639       CASE_MATHFN (BUILT_IN_COSH)
1640       CASE_MATHFN (BUILT_IN_DREM)
1641       CASE_MATHFN (BUILT_IN_ERF)
1642       CASE_MATHFN (BUILT_IN_ERFC)
1643       CASE_MATHFN (BUILT_IN_EXP)
1644       CASE_MATHFN (BUILT_IN_EXP10)
1645       CASE_MATHFN (BUILT_IN_EXP2)
1646       CASE_MATHFN (BUILT_IN_EXPM1)
1647       CASE_MATHFN (BUILT_IN_FABS)
1648       CASE_MATHFN (BUILT_IN_FDIM)
1649       CASE_MATHFN (BUILT_IN_FLOOR)
1650       CASE_MATHFN (BUILT_IN_FMA)
1651       CASE_MATHFN (BUILT_IN_FMAX)
1652       CASE_MATHFN (BUILT_IN_FMIN)
1653       CASE_MATHFN (BUILT_IN_FMOD)
1654       CASE_MATHFN (BUILT_IN_FREXP)
1655       CASE_MATHFN (BUILT_IN_GAMMA)
1656       CASE_MATHFN (BUILT_IN_HUGE_VAL)
1657       CASE_MATHFN (BUILT_IN_HYPOT)
1658       CASE_MATHFN (BUILT_IN_ILOGB)
1659       CASE_MATHFN (BUILT_IN_INF)
1660       CASE_MATHFN (BUILT_IN_J0)
1661       CASE_MATHFN (BUILT_IN_J1)
1662       CASE_MATHFN (BUILT_IN_JN)
1663       CASE_MATHFN (BUILT_IN_LCEIL)
1664       CASE_MATHFN (BUILT_IN_LDEXP)
1665       CASE_MATHFN (BUILT_IN_LFLOOR)
1666       CASE_MATHFN (BUILT_IN_LGAMMA)
1667       CASE_MATHFN (BUILT_IN_LLCEIL)
1668       CASE_MATHFN (BUILT_IN_LLFLOOR)
1669       CASE_MATHFN (BUILT_IN_LLRINT)
1670       CASE_MATHFN (BUILT_IN_LLROUND)
1671       CASE_MATHFN (BUILT_IN_LOG)
1672       CASE_MATHFN (BUILT_IN_LOG10)
1673       CASE_MATHFN (BUILT_IN_LOG1P)
1674       CASE_MATHFN (BUILT_IN_LOG2)
1675       CASE_MATHFN (BUILT_IN_LOGB)
1676       CASE_MATHFN (BUILT_IN_LRINT)
1677       CASE_MATHFN (BUILT_IN_LROUND)
1678       CASE_MATHFN (BUILT_IN_MODF)
1679       CASE_MATHFN (BUILT_IN_NAN)
1680       CASE_MATHFN (BUILT_IN_NANS)
1681       CASE_MATHFN (BUILT_IN_NEARBYINT)
1682       CASE_MATHFN (BUILT_IN_NEXTAFTER)
1683       CASE_MATHFN (BUILT_IN_NEXTTOWARD)
1684       CASE_MATHFN (BUILT_IN_POW)
1685       CASE_MATHFN (BUILT_IN_POWI)
1686       CASE_MATHFN (BUILT_IN_POW10)
1687       CASE_MATHFN (BUILT_IN_REMAINDER)
1688       CASE_MATHFN (BUILT_IN_REMQUO)
1689       CASE_MATHFN (BUILT_IN_RINT)
1690       CASE_MATHFN (BUILT_IN_ROUND)
1691       CASE_MATHFN (BUILT_IN_SCALB)
1692       CASE_MATHFN (BUILT_IN_SCALBLN)
1693       CASE_MATHFN (BUILT_IN_SCALBN)
1694       CASE_MATHFN (BUILT_IN_SIGNIFICAND)
1695       CASE_MATHFN (BUILT_IN_SIN)
1696       CASE_MATHFN (BUILT_IN_SINCOS)
1697       CASE_MATHFN (BUILT_IN_SINH)
1698       CASE_MATHFN (BUILT_IN_SQRT)
1699       CASE_MATHFN (BUILT_IN_TAN)
1700       CASE_MATHFN (BUILT_IN_TANH)
1701       CASE_MATHFN (BUILT_IN_TGAMMA)
1702       CASE_MATHFN (BUILT_IN_TRUNC)
1703       CASE_MATHFN (BUILT_IN_Y0)
1704       CASE_MATHFN (BUILT_IN_Y1)
1705       CASE_MATHFN (BUILT_IN_YN)
1706
1707       default:
1708         return 0;
1709       }
1710
1711   if (TYPE_MAIN_VARIANT (type) == double_type_node)
1712     return implicit_built_in_decls[fcode];
1713   else if (TYPE_MAIN_VARIANT (type) == float_type_node)
1714     return implicit_built_in_decls[fcodef];
1715   else if (TYPE_MAIN_VARIANT (type) == long_double_type_node)
1716     return implicit_built_in_decls[fcodel];
1717   else
1718     return 0;
1719 }
1720
1721 /* If errno must be maintained, expand the RTL to check if the result,
1722    TARGET, of a built-in function call, EXP, is NaN, and if so set
1723    errno to EDOM.  */
1724
1725 static void
1726 expand_errno_check (tree exp, rtx target)
1727 {
1728   rtx lab = gen_label_rtx ();
1729
1730   /* Test the result; if it is NaN, set errno=EDOM because
1731      the argument was not in the domain.  */
1732   emit_cmp_and_jump_insns (target, target, EQ, 0, GET_MODE (target),
1733                            0, lab);
1734
1735 #ifdef TARGET_EDOM
1736   /* If this built-in doesn't throw an exception, set errno directly.  */
1737   if (TREE_NOTHROW (TREE_OPERAND (TREE_OPERAND (exp, 0), 0)))
1738     {
1739 #ifdef GEN_ERRNO_RTX
1740       rtx errno_rtx = GEN_ERRNO_RTX;
1741 #else
1742       rtx errno_rtx
1743           = gen_rtx_MEM (word_mode, gen_rtx_SYMBOL_REF (Pmode, "errno"));
1744 #endif
1745       emit_move_insn (errno_rtx, GEN_INT (TARGET_EDOM));
1746       emit_label (lab);
1747       return;
1748     }
1749 #endif
1750
1751   /* We can't set errno=EDOM directly; let the library call do it.
1752      Pop the arguments right away in case the call gets deleted.  */
1753   NO_DEFER_POP;
1754   expand_call (exp, target, 0);
1755   OK_DEFER_POP;
1756   emit_label (lab);
1757 }
1758
1759
1760 /* Expand a call to one of the builtin math functions (sqrt, exp, or log).
1761    Return 0 if a normal call should be emitted rather than expanding the
1762    function in-line.  EXP is the expression that is a call to the builtin
1763    function; if convenient, the result should be placed in TARGET.
1764    SUBTARGET may be used as the target for computing one of EXP's operands.  */
1765
1766 static rtx
1767 expand_builtin_mathfn (tree exp, rtx target, rtx subtarget)
1768 {
1769   optab builtin_optab;
1770   rtx op0, insns, before_call;
1771   tree fndecl = get_callee_fndecl (exp);
1772   tree arglist = TREE_OPERAND (exp, 1);
1773   enum machine_mode mode;
1774   bool errno_set = false;
1775   tree arg, narg;
1776
1777   if (!validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
1778     return 0;
1779
1780   arg = TREE_VALUE (arglist);
1781
1782   switch (DECL_FUNCTION_CODE (fndecl))
1783     {
1784     case BUILT_IN_SQRT:
1785     case BUILT_IN_SQRTF:
1786     case BUILT_IN_SQRTL:
1787       errno_set = ! tree_expr_nonnegative_p (arg);
1788       builtin_optab = sqrt_optab;
1789       break;
1790     case BUILT_IN_EXP:
1791     case BUILT_IN_EXPF:
1792     case BUILT_IN_EXPL:
1793       errno_set = true; builtin_optab = exp_optab; break;
1794     case BUILT_IN_EXP10:
1795     case BUILT_IN_EXP10F:
1796     case BUILT_IN_EXP10L:
1797     case BUILT_IN_POW10:
1798     case BUILT_IN_POW10F:
1799     case BUILT_IN_POW10L:
1800       errno_set = true; builtin_optab = exp10_optab; break;
1801     case BUILT_IN_EXP2:
1802     case BUILT_IN_EXP2F:
1803     case BUILT_IN_EXP2L:
1804       errno_set = true; builtin_optab = exp2_optab; break;
1805     case BUILT_IN_EXPM1:
1806     case BUILT_IN_EXPM1F:
1807     case BUILT_IN_EXPM1L:
1808       errno_set = true; builtin_optab = expm1_optab; break;
1809     case BUILT_IN_LOGB:
1810     case BUILT_IN_LOGBF:
1811     case BUILT_IN_LOGBL:
1812       errno_set = true; builtin_optab = logb_optab; break;
1813     case BUILT_IN_ILOGB:
1814     case BUILT_IN_ILOGBF:
1815     case BUILT_IN_ILOGBL:
1816       errno_set = true; builtin_optab = ilogb_optab; break;
1817     case BUILT_IN_LOG:
1818     case BUILT_IN_LOGF:
1819     case BUILT_IN_LOGL:
1820       errno_set = true; builtin_optab = log_optab; break;
1821     case BUILT_IN_LOG10:
1822     case BUILT_IN_LOG10F:
1823     case BUILT_IN_LOG10L:
1824       errno_set = true; builtin_optab = log10_optab; break;
1825     case BUILT_IN_LOG2:
1826     case BUILT_IN_LOG2F:
1827     case BUILT_IN_LOG2L:
1828       errno_set = true; builtin_optab = log2_optab; break;
1829     case BUILT_IN_LOG1P:
1830     case BUILT_IN_LOG1PF:
1831     case BUILT_IN_LOG1PL:
1832       errno_set = true; builtin_optab = log1p_optab; break;
1833     case BUILT_IN_ASIN:
1834     case BUILT_IN_ASINF:
1835     case BUILT_IN_ASINL:
1836       builtin_optab = asin_optab; break;
1837     case BUILT_IN_ACOS:
1838     case BUILT_IN_ACOSF:
1839     case BUILT_IN_ACOSL:
1840       builtin_optab = acos_optab; break;
1841     case BUILT_IN_TAN:
1842     case BUILT_IN_TANF:
1843     case BUILT_IN_TANL:
1844       builtin_optab = tan_optab; break;
1845     case BUILT_IN_ATAN:
1846     case BUILT_IN_ATANF:
1847     case BUILT_IN_ATANL:
1848       builtin_optab = atan_optab; break;
1849     case BUILT_IN_FLOOR:
1850     case BUILT_IN_FLOORF:
1851     case BUILT_IN_FLOORL:
1852       builtin_optab = floor_optab; break;
1853     case BUILT_IN_CEIL:
1854     case BUILT_IN_CEILF:
1855     case BUILT_IN_CEILL:
1856       builtin_optab = ceil_optab; break;
1857     case BUILT_IN_TRUNC:
1858     case BUILT_IN_TRUNCF:
1859     case BUILT_IN_TRUNCL:
1860       builtin_optab = btrunc_optab; break;
1861     case BUILT_IN_ROUND:
1862     case BUILT_IN_ROUNDF:
1863     case BUILT_IN_ROUNDL:
1864       builtin_optab = round_optab; break;
1865     case BUILT_IN_NEARBYINT:
1866     case BUILT_IN_NEARBYINTF:
1867     case BUILT_IN_NEARBYINTL:
1868       builtin_optab = nearbyint_optab; break;
1869     case BUILT_IN_RINT:
1870     case BUILT_IN_RINTF:
1871     case BUILT_IN_RINTL:
1872       builtin_optab = rint_optab; break;
1873     case BUILT_IN_LRINT:
1874     case BUILT_IN_LRINTF:
1875     case BUILT_IN_LRINTL:
1876     case BUILT_IN_LLRINT:
1877     case BUILT_IN_LLRINTF:
1878     case BUILT_IN_LLRINTL:
1879       builtin_optab = lrint_optab; break;
1880     default:
1881       gcc_unreachable ();
1882     }
1883
1884   /* Make a suitable register to place result in.  */
1885   mode = TYPE_MODE (TREE_TYPE (exp));
1886
1887   if (! flag_errno_math || ! HONOR_NANS (mode))
1888     errno_set = false;
1889
1890   /* Before working hard, check whether the instruction is available.  */
1891   if (builtin_optab->handlers[(int) mode].insn_code != CODE_FOR_nothing)
1892     {
1893       target = gen_reg_rtx (mode);
1894
1895       /* Wrap the computation of the argument in a SAVE_EXPR, as we may
1896          need to expand the argument again.  This way, we will not perform
1897          side-effects more the once.  */
1898       narg = builtin_save_expr (arg);
1899       if (narg != arg)
1900         {
1901           arg = narg;
1902           arglist = build_tree_list (NULL_TREE, arg);
1903           exp = build_function_call_expr (fndecl, arglist);
1904         }
1905
1906       op0 = expand_expr (arg, subtarget, VOIDmode, 0);
1907
1908       start_sequence ();
1909
1910       /* Compute into TARGET.
1911          Set TARGET to wherever the result comes back.  */
1912       target = expand_unop (mode, builtin_optab, op0, target, 0);
1913
1914       if (target != 0)
1915         {
1916           if (errno_set)
1917             expand_errno_check (exp, target);
1918
1919           /* Output the entire sequence.  */
1920           insns = get_insns ();
1921           end_sequence ();
1922           emit_insn (insns);
1923           return target;
1924         }
1925
1926       /* If we were unable to expand via the builtin, stop the sequence
1927          (without outputting the insns) and call to the library function
1928          with the stabilized argument list.  */
1929       end_sequence ();
1930     }
1931
1932   before_call = get_last_insn ();
1933
1934   target = expand_call (exp, target, target == const0_rtx);
1935
1936   /* If this is a sqrt operation and we don't care about errno, try to
1937      attach a REG_EQUAL note with a SQRT rtx to the emitted libcall.
1938      This allows the semantics of the libcall to be visible to the RTL
1939      optimizers.  */
1940   if (builtin_optab == sqrt_optab && !errno_set)
1941     {
1942       /* Search backwards through the insns emitted by expand_call looking
1943          for the instruction with the REG_RETVAL note.  */
1944       rtx last = get_last_insn ();
1945       while (last != before_call)
1946         {
1947           if (find_reg_note (last, REG_RETVAL, NULL))
1948             {
1949               rtx note = find_reg_note (last, REG_EQUAL, NULL);
1950               /* Check that the REQ_EQUAL note is an EXPR_LIST with
1951                  two elements, i.e. symbol_ref(sqrt) and the operand.  */
1952               if (note
1953                   && GET_CODE (note) == EXPR_LIST
1954                   && GET_CODE (XEXP (note, 0)) == EXPR_LIST
1955                   && XEXP (XEXP (note, 0), 1) != NULL_RTX
1956                   && XEXP (XEXP (XEXP (note, 0), 1), 1) == NULL_RTX)
1957                 {
1958                   rtx operand = XEXP (XEXP (XEXP (note, 0), 1), 0);
1959                   /* Check operand is a register with expected mode.  */
1960                   if (operand
1961                       && REG_P (operand)
1962                       && GET_MODE (operand) == mode)
1963                     {
1964                       /* Replace the REG_EQUAL note with a SQRT rtx.  */
1965                       rtx equiv = gen_rtx_SQRT (mode, operand);
1966                       set_unique_reg_note (last, REG_EQUAL, equiv);
1967                     }
1968                 }
1969               break;
1970             }
1971           last = PREV_INSN (last);
1972         }
1973     }
1974
1975   return target;
1976 }
1977
1978 /* Expand a call to the builtin binary math functions (pow and atan2).
1979    Return 0 if a normal call should be emitted rather than expanding the
1980    function in-line.  EXP is the expression that is a call to the builtin
1981    function; if convenient, the result should be placed in TARGET.
1982    SUBTARGET may be used as the target for computing one of EXP's
1983    operands.  */
1984
1985 static rtx
1986 expand_builtin_mathfn_2 (tree exp, rtx target, rtx subtarget)
1987 {
1988   optab builtin_optab;
1989   rtx op0, op1, insns;
1990   int op1_type = REAL_TYPE;
1991   tree fndecl = get_callee_fndecl (exp);
1992   tree arglist = TREE_OPERAND (exp, 1);
1993   tree arg0, arg1, temp, narg;
1994   enum machine_mode mode;
1995   bool errno_set = true;
1996   bool stable = true;
1997
1998   if ((DECL_FUNCTION_CODE (fndecl) == BUILT_IN_LDEXP)
1999       || (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_LDEXPF)
2000       || (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_LDEXPL))
2001     op1_type = INTEGER_TYPE;
2002
2003   if (!validate_arglist (arglist, REAL_TYPE, op1_type, VOID_TYPE))
2004     return 0;
2005
2006   arg0 = TREE_VALUE (arglist);
2007   arg1 = TREE_VALUE (TREE_CHAIN (arglist));
2008
2009   switch (DECL_FUNCTION_CODE (fndecl))
2010     {
2011     case BUILT_IN_POW:
2012     case BUILT_IN_POWF:
2013     case BUILT_IN_POWL:
2014       builtin_optab = pow_optab; break;
2015     case BUILT_IN_ATAN2:
2016     case BUILT_IN_ATAN2F:
2017     case BUILT_IN_ATAN2L:
2018       builtin_optab = atan2_optab; break;
2019     case BUILT_IN_LDEXP:
2020     case BUILT_IN_LDEXPF:
2021     case BUILT_IN_LDEXPL:
2022       builtin_optab = ldexp_optab; break;
2023     case BUILT_IN_FMOD:
2024     case BUILT_IN_FMODF:
2025     case BUILT_IN_FMODL:
2026       builtin_optab = fmod_optab; break;
2027     case BUILT_IN_DREM:
2028     case BUILT_IN_DREMF:
2029     case BUILT_IN_DREML:
2030       builtin_optab = drem_optab; break;
2031     default:
2032       gcc_unreachable ();
2033     }
2034
2035   /* Make a suitable register to place result in.  */
2036   mode = TYPE_MODE (TREE_TYPE (exp));
2037
2038   /* Before working hard, check whether the instruction is available.  */
2039   if (builtin_optab->handlers[(int) mode].insn_code == CODE_FOR_nothing)
2040     return 0;
2041
2042   target = gen_reg_rtx (mode);
2043
2044   if (! flag_errno_math || ! HONOR_NANS (mode))
2045     errno_set = false;
2046
2047   /* Always stabilize the argument list.  */
2048   narg = builtin_save_expr (arg1);
2049   if (narg != arg1)
2050     {
2051       arg1 = narg;
2052       temp = build_tree_list (NULL_TREE, narg);
2053       stable = false;
2054     }
2055   else
2056     temp = TREE_CHAIN (arglist);
2057
2058   narg = builtin_save_expr (arg0);
2059   if (narg != arg0)
2060     {
2061       arg0 = narg;
2062       arglist = tree_cons (NULL_TREE, narg, temp);
2063       stable = false;
2064     }
2065   else if (! stable)
2066     arglist = tree_cons (NULL_TREE, arg0, temp);
2067
2068   if (! stable)
2069     exp = build_function_call_expr (fndecl, arglist);
2070
2071   op0 = expand_expr (arg0, subtarget, VOIDmode, 0);
2072   op1 = expand_expr (arg1, 0, VOIDmode, 0);
2073
2074   start_sequence ();
2075
2076   /* Compute into TARGET.
2077      Set TARGET to wherever the result comes back.  */
2078   target = expand_binop (mode, builtin_optab, op0, op1,
2079                          target, 0, OPTAB_DIRECT);
2080
2081   /* If we were unable to expand via the builtin, stop the sequence
2082      (without outputting the insns) and call to the library function
2083      with the stabilized argument list.  */
2084   if (target == 0)
2085     {
2086       end_sequence ();
2087       return expand_call (exp, target, target == const0_rtx);
2088     }
2089
2090   if (errno_set)
2091     expand_errno_check (exp, target);
2092
2093   /* Output the entire sequence.  */
2094   insns = get_insns ();
2095   end_sequence ();
2096   emit_insn (insns);
2097
2098   return target;
2099 }
2100
2101 /* Expand a call to the builtin sin and cos math functions.
2102    Return 0 if a normal call should be emitted rather than expanding the
2103    function in-line.  EXP is the expression that is a call to the builtin
2104    function; if convenient, the result should be placed in TARGET.
2105    SUBTARGET may be used as the target for computing one of EXP's
2106    operands.  */
2107
2108 static rtx
2109 expand_builtin_mathfn_3 (tree exp, rtx target, rtx subtarget)
2110 {
2111   optab builtin_optab;
2112   rtx op0, insns;
2113   tree fndecl = get_callee_fndecl (exp);
2114   tree arglist = TREE_OPERAND (exp, 1);
2115   enum machine_mode mode;
2116   bool errno_set = false;
2117   tree arg, narg;
2118
2119   if (!validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
2120     return 0;
2121
2122   arg = TREE_VALUE (arglist);
2123
2124   switch (DECL_FUNCTION_CODE (fndecl))
2125     {
2126     case BUILT_IN_SIN:
2127     case BUILT_IN_SINF:
2128     case BUILT_IN_SINL:
2129     case BUILT_IN_COS:
2130     case BUILT_IN_COSF:
2131     case BUILT_IN_COSL:
2132       builtin_optab = sincos_optab; break;
2133     default:
2134       gcc_unreachable ();
2135     }
2136
2137   /* Make a suitable register to place result in.  */
2138   mode = TYPE_MODE (TREE_TYPE (exp));
2139
2140   if (! flag_errno_math || ! HONOR_NANS (mode))
2141     errno_set = false;
2142
2143   /* Check if sincos insn is available, otherwise fallback
2144      to sin or cos insn.  */
2145   if (builtin_optab->handlers[(int) mode].insn_code == CODE_FOR_nothing) {
2146     switch (DECL_FUNCTION_CODE (fndecl))
2147       {
2148       case BUILT_IN_SIN:
2149       case BUILT_IN_SINF:
2150       case BUILT_IN_SINL:
2151         builtin_optab = sin_optab; break;
2152       case BUILT_IN_COS:
2153       case BUILT_IN_COSF:
2154       case BUILT_IN_COSL:
2155         builtin_optab = cos_optab; break;
2156       default:
2157         gcc_unreachable ();
2158       }
2159   }
2160
2161   /* Before working hard, check whether the instruction is available.  */
2162   if (builtin_optab->handlers[(int) mode].insn_code != CODE_FOR_nothing)
2163     {
2164       target = gen_reg_rtx (mode);
2165
2166       /* Wrap the computation of the argument in a SAVE_EXPR, as we may
2167          need to expand the argument again.  This way, we will not perform
2168          side-effects more the once.  */
2169       narg = save_expr (arg);
2170       if (narg != arg)
2171         {
2172           arg = narg;
2173           arglist = build_tree_list (NULL_TREE, arg);
2174           exp = build_function_call_expr (fndecl, arglist);
2175         }
2176
2177       op0 = expand_expr (arg, subtarget, VOIDmode, 0);
2178
2179       start_sequence ();
2180
2181       /* Compute into TARGET.
2182          Set TARGET to wherever the result comes back.  */
2183       if (builtin_optab == sincos_optab)
2184         {
2185           int result;
2186
2187           switch (DECL_FUNCTION_CODE (fndecl))
2188             {
2189             case BUILT_IN_SIN:
2190             case BUILT_IN_SINF:
2191             case BUILT_IN_SINL:
2192               result = expand_twoval_unop (builtin_optab, op0, 0, target, 0);
2193               break;
2194             case BUILT_IN_COS:
2195             case BUILT_IN_COSF:
2196             case BUILT_IN_COSL:
2197               result = expand_twoval_unop (builtin_optab, op0, target, 0, 0);
2198               break;
2199             default:
2200               gcc_unreachable ();
2201             }
2202           gcc_assert (result);
2203         }
2204       else
2205         {
2206           target = expand_unop (mode, builtin_optab, op0, target, 0);
2207         }
2208
2209       if (target != 0)
2210         {
2211           if (errno_set)
2212             expand_errno_check (exp, target);
2213
2214           /* Output the entire sequence.  */
2215           insns = get_insns ();
2216           end_sequence ();
2217           emit_insn (insns);
2218           return target;
2219         }
2220
2221       /* If we were unable to expand via the builtin, stop the sequence
2222          (without outputting the insns) and call to the library function
2223          with the stabilized argument list.  */
2224       end_sequence ();
2225     }
2226
2227   target = expand_call (exp, target, target == const0_rtx);
2228
2229   return target;
2230 }
2231
2232 /* Expand a call to one of the builtin rounding functions (lfloor).
2233    If expanding via optab fails, lower expression to (int)(floor(x)).
2234    EXP is the expression that is a call to the builtin function;
2235    if convenient, the result should be placed in TARGET.  SUBTARGET may
2236    be used as the target for computing one of EXP's operands.  */
2237
2238 static rtx
2239 expand_builtin_int_roundingfn (tree exp, rtx target, rtx subtarget)
2240 {
2241   optab builtin_optab;
2242   rtx op0, insns, tmp;
2243   tree fndecl = get_callee_fndecl (exp);
2244   tree arglist = TREE_OPERAND (exp, 1);
2245   enum built_in_function fallback_fn;
2246   tree fallback_fndecl;
2247   enum machine_mode mode;
2248   tree arg, narg;
2249
2250   if (!validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
2251     gcc_unreachable ();
2252
2253   arg = TREE_VALUE (arglist);
2254
2255   switch (DECL_FUNCTION_CODE (fndecl))
2256     {
2257     case BUILT_IN_LCEIL:
2258     case BUILT_IN_LCEILF:
2259     case BUILT_IN_LCEILL:
2260     case BUILT_IN_LLCEIL:
2261     case BUILT_IN_LLCEILF:
2262     case BUILT_IN_LLCEILL:
2263       builtin_optab = lceil_optab;
2264       fallback_fn = BUILT_IN_CEIL;
2265       break;
2266
2267     case BUILT_IN_LFLOOR:
2268     case BUILT_IN_LFLOORF:
2269     case BUILT_IN_LFLOORL:
2270     case BUILT_IN_LLFLOOR:
2271     case BUILT_IN_LLFLOORF:
2272     case BUILT_IN_LLFLOORL:
2273       builtin_optab = lfloor_optab;
2274       fallback_fn = BUILT_IN_FLOOR;
2275       break;
2276
2277     default:
2278       gcc_unreachable ();
2279     }
2280
2281   /* Make a suitable register to place result in.  */
2282   mode = TYPE_MODE (TREE_TYPE (exp));
2283
2284   /* Before working hard, check whether the instruction is available.  */
2285   if (builtin_optab->handlers[(int) mode].insn_code != CODE_FOR_nothing)
2286     {
2287       target = gen_reg_rtx (mode);
2288
2289       /* Wrap the computation of the argument in a SAVE_EXPR, as we may
2290          need to expand the argument again.  This way, we will not perform
2291          side-effects more the once.  */
2292       narg = builtin_save_expr (arg);
2293       if (narg != arg)
2294         {
2295           arg = narg;
2296           arglist = build_tree_list (NULL_TREE, arg);
2297           exp = build_function_call_expr (fndecl, arglist);
2298         }
2299
2300       op0 = expand_expr (arg, subtarget, VOIDmode, 0);
2301
2302       start_sequence ();
2303
2304       /* Compute into TARGET.
2305          Set TARGET to wherever the result comes back.  */
2306       target = expand_unop (mode, builtin_optab, op0, target, 0);
2307
2308       if (target != 0)
2309         {
2310           /* Output the entire sequence.  */
2311           insns = get_insns ();
2312           end_sequence ();
2313           emit_insn (insns);
2314           return target;
2315         }
2316
2317       /* If we were unable to expand via the builtin, stop the sequence
2318          (without outputting the insns).  */
2319       end_sequence ();
2320     }
2321
2322   /* Fall back to floating point rounding optab.  */
2323   fallback_fndecl = mathfn_built_in (TREE_TYPE (arg), fallback_fn);
2324   /* We shouldn't get here on targets without TARGET_C99_FUNCTIONS.
2325      ??? Perhaps convert (int)floorf(x) into (int)floor((double)x).  */
2326   gcc_assert (fallback_fndecl != NULL_TREE);
2327   exp = build_function_call_expr (fallback_fndecl, arglist);
2328
2329   tmp = expand_builtin_mathfn (exp, NULL_RTX, NULL_RTX);
2330
2331   /* Truncate the result of floating point optab to integer
2332      via expand_fix ().  */
2333   target = gen_reg_rtx (mode);
2334   expand_fix (target, tmp, 0);
2335
2336   return target;
2337 }
2338
2339 /* To evaluate powi(x,n), the floating point value x raised to the
2340    constant integer exponent n, we use a hybrid algorithm that
2341    combines the "window method" with look-up tables.  For an
2342    introduction to exponentiation algorithms and "addition chains",
2343    see section 4.6.3, "Evaluation of Powers" of Donald E. Knuth,
2344    "Seminumerical Algorithms", Vol. 2, "The Art of Computer Programming",
2345    3rd Edition, 1998, and Daniel M. Gordon, "A Survey of Fast Exponentiation
2346    Methods", Journal of Algorithms, Vol. 27, pp. 129-146, 1998.  */
2347
2348 /* Provide a default value for POWI_MAX_MULTS, the maximum number of
2349    multiplications to inline before calling the system library's pow
2350    function.  powi(x,n) requires at worst 2*bits(n)-2 multiplications,
2351    so this default never requires calling pow, powf or powl.  */
2352
2353 #ifndef POWI_MAX_MULTS
2354 #define POWI_MAX_MULTS  (2*HOST_BITS_PER_WIDE_INT-2)
2355 #endif
2356
2357 /* The size of the "optimal power tree" lookup table.  All
2358    exponents less than this value are simply looked up in the
2359    powi_table below.  This threshold is also used to size the
2360    cache of pseudo registers that hold intermediate results.  */
2361 #define POWI_TABLE_SIZE 256
2362
2363 /* The size, in bits of the window, used in the "window method"
2364    exponentiation algorithm.  This is equivalent to a radix of
2365    (1<<POWI_WINDOW_SIZE) in the corresponding "m-ary method".  */
2366 #define POWI_WINDOW_SIZE 3
2367
2368 /* The following table is an efficient representation of an
2369    "optimal power tree".  For each value, i, the corresponding
2370    value, j, in the table states than an optimal evaluation
2371    sequence for calculating pow(x,i) can be found by evaluating
2372    pow(x,j)*pow(x,i-j).  An optimal power tree for the first
2373    100 integers is given in Knuth's "Seminumerical algorithms".  */
2374
2375 static const unsigned char powi_table[POWI_TABLE_SIZE] =
2376   {
2377       0,   1,   1,   2,   2,   3,   3,   4,  /*   0 -   7 */
2378       4,   6,   5,   6,   6,  10,   7,   9,  /*   8 -  15 */
2379       8,  16,   9,  16,  10,  12,  11,  13,  /*  16 -  23 */
2380      12,  17,  13,  18,  14,  24,  15,  26,  /*  24 -  31 */
2381      16,  17,  17,  19,  18,  33,  19,  26,  /*  32 -  39 */
2382      20,  25,  21,  40,  22,  27,  23,  44,  /*  40 -  47 */
2383      24,  32,  25,  34,  26,  29,  27,  44,  /*  48 -  55 */
2384      28,  31,  29,  34,  30,  60,  31,  36,  /*  56 -  63 */
2385      32,  64,  33,  34,  34,  46,  35,  37,  /*  64 -  71 */
2386      36,  65,  37,  50,  38,  48,  39,  69,  /*  72 -  79 */
2387      40,  49,  41,  43,  42,  51,  43,  58,  /*  80 -  87 */
2388      44,  64,  45,  47,  46,  59,  47,  76,  /*  88 -  95 */
2389      48,  65,  49,  66,  50,  67,  51,  66,  /*  96 - 103 */
2390      52,  70,  53,  74,  54, 104,  55,  74,  /* 104 - 111 */
2391      56,  64,  57,  69,  58,  78,  59,  68,  /* 112 - 119 */
2392      60,  61,  61,  80,  62,  75,  63,  68,  /* 120 - 127 */
2393      64,  65,  65, 128,  66, 129,  67,  90,  /* 128 - 135 */
2394      68,  73,  69, 131,  70,  94,  71,  88,  /* 136 - 143 */
2395      72, 128,  73,  98,  74, 132,  75, 121,  /* 144 - 151 */
2396      76, 102,  77, 124,  78, 132,  79, 106,  /* 152 - 159 */
2397      80,  97,  81, 160,  82,  99,  83, 134,  /* 160 - 167 */
2398      84,  86,  85,  95,  86, 160,  87, 100,  /* 168 - 175 */
2399      88, 113,  89,  98,  90, 107,  91, 122,  /* 176 - 183 */
2400      92, 111,  93, 102,  94, 126,  95, 150,  /* 184 - 191 */
2401      96, 128,  97, 130,  98, 133,  99, 195,  /* 192 - 199 */
2402     100, 128, 101, 123, 102, 164, 103, 138,  /* 200 - 207 */
2403     104, 145, 105, 146, 106, 109, 107, 149,  /* 208 - 215 */
2404     108, 200, 109, 146, 110, 170, 111, 157,  /* 216 - 223 */
2405     112, 128, 113, 130, 114, 182, 115, 132,  /* 224 - 231 */
2406     116, 200, 117, 132, 118, 158, 119, 206,  /* 232 - 239 */
2407     120, 240, 121, 162, 122, 147, 123, 152,  /* 240 - 247 */
2408     124, 166, 125, 214, 126, 138, 127, 153,  /* 248 - 255 */
2409   };
2410
2411
2412 /* Return the number of multiplications required to calculate
2413    powi(x,n) where n is less than POWI_TABLE_SIZE.  This is a
2414    subroutine of powi_cost.  CACHE is an array indicating
2415    which exponents have already been calculated.  */
2416
2417 static int
2418 powi_lookup_cost (unsigned HOST_WIDE_INT n, bool *cache)
2419 {
2420   /* If we've already calculated this exponent, then this evaluation
2421      doesn't require any additional multiplications.  */
2422   if (cache[n])
2423     return 0;
2424
2425   cache[n] = true;
2426   return powi_lookup_cost (n - powi_table[n], cache)
2427          + powi_lookup_cost (powi_table[n], cache) + 1;
2428 }
2429
2430 /* Return the number of multiplications required to calculate
2431    powi(x,n) for an arbitrary x, given the exponent N.  This
2432    function needs to be kept in sync with expand_powi below.  */
2433
2434 static int
2435 powi_cost (HOST_WIDE_INT n)
2436 {
2437   bool cache[POWI_TABLE_SIZE];
2438   unsigned HOST_WIDE_INT digit;
2439   unsigned HOST_WIDE_INT val;
2440   int result;
2441
2442   if (n == 0)
2443     return 0;
2444
2445   /* Ignore the reciprocal when calculating the cost.  */
2446   val = (n < 0) ? -n : n;
2447
2448   /* Initialize the exponent cache.  */
2449   memset (cache, 0, POWI_TABLE_SIZE * sizeof (bool));
2450   cache[1] = true;
2451
2452   result = 0;
2453
2454   while (val >= POWI_TABLE_SIZE)
2455     {
2456       if (val & 1)
2457         {
2458           digit = val & ((1 << POWI_WINDOW_SIZE) - 1);
2459           result += powi_lookup_cost (digit, cache)
2460                     + POWI_WINDOW_SIZE + 1;
2461           val >>= POWI_WINDOW_SIZE;
2462         }
2463       else
2464         {
2465           val >>= 1;
2466           result++;
2467         }
2468     }
2469
2470   return result + powi_lookup_cost (val, cache);
2471 }
2472
2473 /* Recursive subroutine of expand_powi.  This function takes the array,
2474    CACHE, of already calculated exponents and an exponent N and returns
2475    an RTX that corresponds to CACHE[1]**N, as calculated in mode MODE.  */
2476
2477 static rtx
2478 expand_powi_1 (enum machine_mode mode, unsigned HOST_WIDE_INT n, rtx *cache)
2479 {
2480   unsigned HOST_WIDE_INT digit;
2481   rtx target, result;
2482   rtx op0, op1;
2483
2484   if (n < POWI_TABLE_SIZE)
2485     {
2486       if (cache[n])
2487         return cache[n];
2488
2489       target = gen_reg_rtx (mode);
2490       cache[n] = target;
2491
2492       op0 = expand_powi_1 (mode, n - powi_table[n], cache);
2493       op1 = expand_powi_1 (mode, powi_table[n], cache);
2494     }
2495   else if (n & 1)
2496     {
2497       target = gen_reg_rtx (mode);
2498       digit = n & ((1 << POWI_WINDOW_SIZE) - 1);
2499       op0 = expand_powi_1 (mode, n - digit, cache);
2500       op1 = expand_powi_1 (mode, digit, cache);
2501     }
2502   else
2503     {
2504       target = gen_reg_rtx (mode);
2505       op0 = expand_powi_1 (mode, n >> 1, cache);
2506       op1 = op0;
2507     }
2508
2509   result = expand_mult (mode, op0, op1, target, 0);
2510   if (result != target)
2511     emit_move_insn (target, result);
2512   return target;
2513 }
2514
2515 /* Expand the RTL to evaluate powi(x,n) in mode MODE.  X is the
2516    floating point operand in mode MODE, and N is the exponent.  This
2517    function needs to be kept in sync with powi_cost above.  */
2518
2519 static rtx
2520 expand_powi (rtx x, enum machine_mode mode, HOST_WIDE_INT n)
2521 {
2522   unsigned HOST_WIDE_INT val;
2523   rtx cache[POWI_TABLE_SIZE];
2524   rtx result;
2525
2526   if (n == 0)
2527     return CONST1_RTX (mode);
2528
2529   val = (n < 0) ? -n : n;
2530
2531   memset (cache, 0, sizeof (cache));
2532   cache[1] = x;
2533
2534   result = expand_powi_1 (mode, (n < 0) ? -n : n, cache);
2535
2536   /* If the original exponent was negative, reciprocate the result.  */
2537   if (n < 0)
2538     result = expand_binop (mode, sdiv_optab, CONST1_RTX (mode),
2539                            result, NULL_RTX, 0, OPTAB_LIB_WIDEN);
2540
2541   return result;
2542 }
2543
2544 /* Expand a call to the pow built-in mathematical function.  Return 0 if
2545    a normal call should be emitted rather than expanding the function
2546    in-line.  EXP is the expression that is a call to the builtin
2547    function; if convenient, the result should be placed in TARGET.  */
2548
2549 static rtx
2550 expand_builtin_pow (tree exp, rtx target, rtx subtarget)
2551 {
2552   tree arglist = TREE_OPERAND (exp, 1);
2553   tree arg0, arg1;
2554
2555   if (! validate_arglist (arglist, REAL_TYPE, REAL_TYPE, VOID_TYPE))
2556     return 0;
2557
2558   arg0 = TREE_VALUE (arglist);
2559   arg1 = TREE_VALUE (TREE_CHAIN (arglist));
2560
2561   if (TREE_CODE (arg1) == REAL_CST
2562       && ! TREE_CONSTANT_OVERFLOW (arg1))
2563     {
2564       REAL_VALUE_TYPE cint;
2565       REAL_VALUE_TYPE c;
2566       HOST_WIDE_INT n;
2567
2568       c = TREE_REAL_CST (arg1);
2569       n = real_to_integer (&c);
2570       real_from_integer (&cint, VOIDmode, n, n < 0 ? -1 : 0, 0);
2571       if (real_identical (&c, &cint))
2572         {
2573           /* If the exponent is -1, 0, 1 or 2, then expand_powi is exact.
2574              Otherwise, check the number of multiplications required.
2575              Note that pow never sets errno for an integer exponent.  */
2576           if ((n >= -1 && n <= 2)
2577               || (flag_unsafe_math_optimizations
2578                   && ! optimize_size
2579                   && powi_cost (n) <= POWI_MAX_MULTS))
2580             {
2581               enum machine_mode mode = TYPE_MODE (TREE_TYPE (exp));
2582               rtx op = expand_expr (arg0, subtarget, VOIDmode, 0);
2583               op = force_reg (mode, op);
2584               return expand_powi (op, mode, n);
2585             }
2586         }
2587     }
2588
2589   if (! flag_unsafe_math_optimizations)
2590     return NULL_RTX;
2591   return expand_builtin_mathfn_2 (exp, target, subtarget);
2592 }
2593
2594 /* Expand a call to the powi built-in mathematical function.  Return 0 if
2595    a normal call should be emitted rather than expanding the function
2596    in-line.  EXP is the expression that is a call to the builtin
2597    function; if convenient, the result should be placed in TARGET.  */
2598
2599 static rtx
2600 expand_builtin_powi (tree exp, rtx target, rtx subtarget)
2601 {
2602   tree arglist = TREE_OPERAND (exp, 1);
2603   tree arg0, arg1;
2604   rtx op0, op1;
2605   enum machine_mode mode;
2606   enum machine_mode mode2;
2607
2608   if (! validate_arglist (arglist, REAL_TYPE, INTEGER_TYPE, VOID_TYPE))
2609     return 0;
2610
2611   arg0 = TREE_VALUE (arglist);
2612   arg1 = TREE_VALUE (TREE_CHAIN (arglist));
2613   mode = TYPE_MODE (TREE_TYPE (exp));
2614
2615   /* Handle constant power.  */
2616
2617   if (TREE_CODE (arg1) == INTEGER_CST
2618       && ! TREE_CONSTANT_OVERFLOW (arg1))
2619     {
2620       HOST_WIDE_INT n = TREE_INT_CST_LOW (arg1);
2621
2622       /* If the exponent is -1, 0, 1 or 2, then expand_powi is exact.
2623          Otherwise, check the number of multiplications required.  */
2624       if ((TREE_INT_CST_HIGH (arg1) == 0
2625            || TREE_INT_CST_HIGH (arg1) == -1)
2626           && ((n >= -1 && n <= 2)
2627               || (! optimize_size
2628                   && powi_cost (n) <= POWI_MAX_MULTS)))
2629         {
2630           op0 = expand_expr (arg0, subtarget, VOIDmode, 0);
2631           op0 = force_reg (mode, op0);
2632           return expand_powi (op0, mode, n);
2633         }
2634     }
2635
2636   /* Emit a libcall to libgcc.  */
2637
2638   /* Mode of the 2nd argument must match that of an int. */
2639   mode2 = mode_for_size (INT_TYPE_SIZE, MODE_INT, 0);
2640
2641   if (target == NULL_RTX)
2642     target = gen_reg_rtx (mode);
2643
2644   op0 = expand_expr (arg0, subtarget, mode, 0);
2645   if (GET_MODE (op0) != mode)
2646     op0 = convert_to_mode (mode, op0, 0);
2647   op1 = expand_expr (arg1, 0, mode2, 0);
2648   if (GET_MODE (op1) != mode2)
2649     op1 = convert_to_mode (mode2, op1, 0);
2650
2651   target = emit_library_call_value (powi_optab->handlers[(int) mode].libfunc,
2652                                     target, LCT_CONST_MAKE_BLOCK, mode, 2,
2653                                     op0, mode, op1, mode2);
2654
2655   return target;
2656 }
2657
2658 /* Expand expression EXP which is a call to the strlen builtin.  Return 0
2659    if we failed the caller should emit a normal call, otherwise
2660    try to get the result in TARGET, if convenient.  */
2661
2662 static rtx
2663 expand_builtin_strlen (tree arglist, rtx target,
2664                        enum machine_mode target_mode)
2665 {
2666   if (!validate_arglist (arglist, POINTER_TYPE, VOID_TYPE))
2667     return 0;
2668   else
2669     {
2670       rtx pat;
2671       tree len, src = TREE_VALUE (arglist);
2672       rtx result, src_reg, char_rtx, before_strlen;
2673       enum machine_mode insn_mode = target_mode, char_mode;
2674       enum insn_code icode = CODE_FOR_nothing;
2675       int align;
2676
2677       /* If the length can be computed at compile-time, return it.  */
2678       len = c_strlen (src, 0);
2679       if (len)
2680         return expand_expr (len, target, target_mode, EXPAND_NORMAL);
2681
2682       /* If the length can be computed at compile-time and is constant
2683          integer, but there are side-effects in src, evaluate
2684          src for side-effects, then return len.
2685          E.g. x = strlen (i++ ? "xfoo" + 1 : "bar");
2686          can be optimized into: i++; x = 3;  */
2687       len = c_strlen (src, 1);
2688       if (len && TREE_CODE (len) == INTEGER_CST)
2689         {
2690           expand_expr (src, const0_rtx, VOIDmode, EXPAND_NORMAL);
2691           return expand_expr (len, target, target_mode, EXPAND_NORMAL);
2692         }
2693
2694       align = get_pointer_alignment (src, BIGGEST_ALIGNMENT) / BITS_PER_UNIT;
2695
2696       /* If SRC is not a pointer type, don't do this operation inline.  */
2697       if (align == 0)
2698         return 0;
2699
2700       /* Bail out if we can't compute strlen in the right mode.  */
2701       while (insn_mode != VOIDmode)
2702         {
2703           icode = strlen_optab->handlers[(int) insn_mode].insn_code;
2704           if (icode != CODE_FOR_nothing)
2705             break;
2706
2707           insn_mode = GET_MODE_WIDER_MODE (insn_mode);
2708         }
2709       if (insn_mode == VOIDmode)
2710         return 0;
2711
2712       /* Make a place to write the result of the instruction.  */
2713       result = target;
2714       if (! (result != 0
2715              && REG_P (result)
2716              && GET_MODE (result) == insn_mode
2717              && REGNO (result) >= FIRST_PSEUDO_REGISTER))
2718         result = gen_reg_rtx (insn_mode);
2719
2720       /* Make a place to hold the source address.  We will not expand
2721          the actual source until we are sure that the expansion will
2722          not fail -- there are trees that cannot be expanded twice.  */
2723       src_reg = gen_reg_rtx (Pmode);
2724
2725       /* Mark the beginning of the strlen sequence so we can emit the
2726          source operand later.  */
2727       before_strlen = get_last_insn ();
2728
2729       char_rtx = const0_rtx;
2730       char_mode = insn_data[(int) icode].operand[2].mode;
2731       if (! (*insn_data[(int) icode].operand[2].predicate) (char_rtx,
2732                                                             char_mode))
2733         char_rtx = copy_to_mode_reg (char_mode, char_rtx);
2734
2735       pat = GEN_FCN (icode) (result, gen_rtx_MEM (BLKmode, src_reg),
2736                              char_rtx, GEN_INT (align));
2737       if (! pat)
2738         return 0;
2739       emit_insn (pat);
2740
2741       /* Now that we are assured of success, expand the source.  */
2742       start_sequence ();
2743       pat = expand_expr (src, src_reg, ptr_mode, EXPAND_NORMAL);
2744       if (pat != src_reg)
2745         emit_move_insn (src_reg, pat);
2746       pat = get_insns ();
2747       end_sequence ();
2748
2749       if (before_strlen)
2750         emit_insn_after (pat, before_strlen);
2751       else
2752         emit_insn_before (pat, get_insns ());
2753
2754       /* Return the value in the proper mode for this function.  */
2755       if (GET_MODE (result) == target_mode)
2756         target = result;
2757       else if (target != 0)
2758         convert_move (target, result, 0);
2759       else
2760         target = convert_to_mode (target_mode, result, 0);
2761
2762       return target;
2763     }
2764 }
2765
2766 /* Expand a call to the strstr builtin.  Return 0 if we failed the
2767    caller should emit a normal call, otherwise try to get the result
2768    in TARGET, if convenient (and in mode MODE if that's convenient).  */
2769
2770 static rtx
2771 expand_builtin_strstr (tree arglist, tree type, rtx target, enum machine_mode mode)
2772 {
2773   if (validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
2774     {
2775       tree result = fold_builtin_strstr (arglist, type);
2776       if (result)
2777         return expand_expr (result, target, mode, EXPAND_NORMAL);
2778     }
2779   return 0;
2780 }
2781
2782 /* Expand a call to the strchr builtin.  Return 0 if we failed the
2783    caller should emit a normal call, otherwise try to get the result
2784    in TARGET, if convenient (and in mode MODE if that's convenient).  */
2785
2786 static rtx
2787 expand_builtin_strchr (tree arglist, tree type, rtx target, enum machine_mode mode)
2788 {
2789   if (validate_arglist (arglist, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
2790     {
2791       tree result = fold_builtin_strchr (arglist, type);
2792       if (result)
2793         return expand_expr (result, target, mode, EXPAND_NORMAL);
2794
2795       /* FIXME: Should use strchrM optab so that ports can optimize this.  */
2796     }
2797   return 0;
2798 }
2799
2800 /* Expand a call to the strrchr builtin.  Return 0 if we failed the
2801    caller should emit a normal call, otherwise try to get the result
2802    in TARGET, if convenient (and in mode MODE if that's convenient).  */
2803
2804 static rtx
2805 expand_builtin_strrchr (tree arglist, tree type, rtx target, enum machine_mode mode)
2806 {
2807   if (validate_arglist (arglist, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
2808     {
2809       tree result = fold_builtin_strrchr (arglist, type);
2810       if (result)
2811         return expand_expr (result, target, mode, EXPAND_NORMAL);
2812     }
2813   return 0;
2814 }
2815
2816 /* Expand a call to the strpbrk builtin.  Return 0 if we failed the
2817    caller should emit a normal call, otherwise try to get the result
2818    in TARGET, if convenient (and in mode MODE if that's convenient).  */
2819
2820 static rtx
2821 expand_builtin_strpbrk (tree arglist, tree type, rtx target, enum machine_mode mode)
2822 {
2823   if (validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
2824     {
2825       tree result = fold_builtin_strpbrk (arglist, type);
2826       if (result)
2827         return expand_expr (result, target, mode, EXPAND_NORMAL);
2828     }
2829   return 0;
2830 }
2831
2832 /* Callback routine for store_by_pieces.  Read GET_MODE_BITSIZE (MODE)
2833    bytes from constant string DATA + OFFSET and return it as target
2834    constant.  */
2835
2836 static rtx
2837 builtin_memcpy_read_str (void *data, HOST_WIDE_INT offset,
2838                          enum machine_mode mode)
2839 {
2840   const char *str = (const char *) data;
2841
2842   gcc_assert (offset >= 0
2843               && ((unsigned HOST_WIDE_INT) offset + GET_MODE_SIZE (mode)
2844                   <= strlen (str) + 1));
2845
2846   return c_readstr (str + offset, mode);
2847 }
2848
2849 /* Expand a call to the memcpy builtin, with arguments in ARGLIST.
2850    Return 0 if we failed, the caller should emit a normal call,
2851    otherwise try to get the result in TARGET, if convenient (and in
2852    mode MODE if that's convenient).  */
2853 static rtx
2854 expand_builtin_memcpy (tree exp, rtx target, enum machine_mode mode)
2855 {
2856   tree fndecl = get_callee_fndecl (exp);
2857   tree arglist = TREE_OPERAND (exp, 1);
2858   if (!validate_arglist (arglist,
2859                          POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
2860     return 0;
2861   else
2862     {
2863       tree dest = TREE_VALUE (arglist);
2864       tree src = TREE_VALUE (TREE_CHAIN (arglist));
2865       tree len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
2866       const char *src_str;
2867       unsigned int src_align = get_pointer_alignment (src, BIGGEST_ALIGNMENT);
2868       unsigned int dest_align
2869         = get_pointer_alignment (dest, BIGGEST_ALIGNMENT);
2870       rtx dest_mem, src_mem, dest_addr, len_rtx;
2871       tree result = fold_builtin_memcpy (fndecl, arglist);
2872
2873       if (result)
2874         return expand_expr (result, target, mode, EXPAND_NORMAL);
2875
2876       /* If DEST is not a pointer type, call the normal function.  */
2877       if (dest_align == 0)
2878         return 0;
2879
2880       /* If either SRC is not a pointer type, don't do this
2881          operation in-line.  */
2882       if (src_align == 0)
2883         return 0;
2884
2885       dest_mem = get_memory_rtx (dest, len);
2886       set_mem_align (dest_mem, dest_align);
2887       len_rtx = expand_expr (len, NULL_RTX, VOIDmode, 0);
2888       src_str = c_getstr (src);
2889
2890       /* If SRC is a string constant and block move would be done
2891          by pieces, we can avoid loading the string from memory
2892          and only stored the computed constants.  */
2893       if (src_str
2894           && GET_CODE (len_rtx) == CONST_INT
2895           && (unsigned HOST_WIDE_INT) INTVAL (len_rtx) <= strlen (src_str) + 1
2896           && can_store_by_pieces (INTVAL (len_rtx), builtin_memcpy_read_str,
2897                                   (void *) src_str, dest_align))
2898         {
2899           dest_mem = store_by_pieces (dest_mem, INTVAL (len_rtx),
2900                                       builtin_memcpy_read_str,
2901                                       (void *) src_str, dest_align, 0);
2902           dest_mem = force_operand (XEXP (dest_mem, 0), NULL_RTX);
2903           dest_mem = convert_memory_address (ptr_mode, dest_mem);
2904           return dest_mem;
2905         }
2906
2907       src_mem = get_memory_rtx (src, len);
2908       set_mem_align (src_mem, src_align);
2909
2910       /* Copy word part most expediently.  */
2911       dest_addr = emit_block_move (dest_mem, src_mem, len_rtx,
2912                                    CALL_EXPR_TAILCALL (exp)
2913                                    ? BLOCK_OP_TAILCALL : BLOCK_OP_NORMAL);
2914
2915       if (dest_addr == 0)
2916         {
2917           dest_addr = force_operand (XEXP (dest_mem, 0), NULL_RTX);
2918           dest_addr = convert_memory_address (ptr_mode, dest_addr);
2919         }
2920       return dest_addr;
2921     }
2922 }
2923
2924 /* Expand a call to the mempcpy builtin, with arguments in ARGLIST.
2925    Return 0 if we failed; the caller should emit a normal call,
2926    otherwise try to get the result in TARGET, if convenient (and in
2927    mode MODE if that's convenient).  If ENDP is 0 return the
2928    destination pointer, if ENDP is 1 return the end pointer ala
2929    mempcpy, and if ENDP is 2 return the end pointer minus one ala
2930    stpcpy.  */
2931
2932 static rtx
2933 expand_builtin_mempcpy (tree arglist, tree type, rtx target, enum machine_mode mode,
2934                         int endp)
2935 {
2936   if (!validate_arglist (arglist,
2937                          POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
2938     return 0;
2939   /* If return value is ignored, transform mempcpy into memcpy.  */
2940   else if (target == const0_rtx)
2941     {
2942       tree fn = implicit_built_in_decls[BUILT_IN_MEMCPY];
2943
2944       if (!fn)
2945         return 0;
2946
2947       return expand_expr (build_function_call_expr (fn, arglist),
2948                           target, mode, EXPAND_NORMAL);
2949     }
2950   else
2951     {
2952       tree dest = TREE_VALUE (arglist);
2953       tree src = TREE_VALUE (TREE_CHAIN (arglist));
2954       tree len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
2955       const char *src_str;
2956       unsigned int src_align = get_pointer_alignment (src, BIGGEST_ALIGNMENT);
2957       unsigned int dest_align
2958         = get_pointer_alignment (dest, BIGGEST_ALIGNMENT);
2959       rtx dest_mem, src_mem, len_rtx;
2960       tree result = fold_builtin_mempcpy (arglist, type, endp);
2961
2962       if (result)
2963         return expand_expr (result, target, mode, EXPAND_NORMAL);
2964
2965       /* If either SRC or DEST is not a pointer type, don't do this
2966          operation in-line.  */
2967       if (dest_align == 0 || src_align == 0)
2968         return 0;
2969
2970       /* If LEN is not constant, call the normal function.  */
2971       if (! host_integerp (len, 1))
2972         return 0;
2973
2974       len_rtx = expand_expr (len, NULL_RTX, VOIDmode, 0);
2975       src_str = c_getstr (src);
2976
2977       /* If SRC is a string constant and block move would be done
2978          by pieces, we can avoid loading the string from memory
2979          and only stored the computed constants.  */
2980       if (src_str
2981           && GET_CODE (len_rtx) == CONST_INT
2982           && (unsigned HOST_WIDE_INT) INTVAL (len_rtx) <= strlen (src_str) + 1
2983           && can_store_by_pieces (INTVAL (len_rtx), builtin_memcpy_read_str,
2984                                   (void *) src_str, dest_align))
2985         {
2986           dest_mem = get_memory_rtx (dest, len);
2987           set_mem_align (dest_mem, dest_align);
2988           dest_mem = store_by_pieces (dest_mem, INTVAL (len_rtx),
2989                                       builtin_memcpy_read_str,
2990                                       (void *) src_str, dest_align, endp);
2991           dest_mem = force_operand (XEXP (dest_mem, 0), NULL_RTX);
2992           dest_mem = convert_memory_address (ptr_mode, dest_mem);
2993           return dest_mem;
2994         }
2995
2996       if (GET_CODE (len_rtx) == CONST_INT
2997           && can_move_by_pieces (INTVAL (len_rtx),
2998                                  MIN (dest_align, src_align)))
2999         {
3000           dest_mem = get_memory_rtx (dest, len);
3001           set_mem_align (dest_mem, dest_align);
3002           src_mem = get_memory_rtx (src, len);
3003           set_mem_align (src_mem, src_align);
3004           dest_mem = move_by_pieces (dest_mem, src_mem, INTVAL (len_rtx),
3005                                      MIN (dest_align, src_align), endp);
3006           dest_mem = force_operand (XEXP (dest_mem, 0), NULL_RTX);
3007           dest_mem = convert_memory_address (ptr_mode, dest_mem);
3008           return dest_mem;
3009         }
3010
3011       return 0;
3012     }
3013 }
3014
3015 /* Expand expression EXP, which is a call to the memmove builtin.  Return 0
3016    if we failed; the caller should emit a normal call.  */
3017
3018 static rtx
3019 expand_builtin_memmove (tree arglist, tree type, rtx target,
3020                         enum machine_mode mode, tree orig_exp)
3021 {
3022   if (!validate_arglist (arglist,
3023                          POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
3024     return 0;
3025   else
3026     {
3027       tree dest = TREE_VALUE (arglist);
3028       tree src = TREE_VALUE (TREE_CHAIN (arglist));
3029       tree len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
3030
3031       unsigned int src_align = get_pointer_alignment (src, BIGGEST_ALIGNMENT);
3032       unsigned int dest_align
3033         = get_pointer_alignment (dest, BIGGEST_ALIGNMENT);
3034       tree result = fold_builtin_memmove (arglist, type);
3035
3036       if (result)
3037         return expand_expr (result, target, mode, EXPAND_NORMAL);
3038
3039       /* If DEST is not a pointer type, call the normal function.  */
3040       if (dest_align == 0)
3041         return 0;
3042
3043       /* If either SRC is not a pointer type, don't do this
3044          operation in-line.  */
3045       if (src_align == 0)
3046         return 0;
3047
3048       /* If src is categorized for a readonly section we can use
3049          normal memcpy.  */
3050       if (readonly_data_expr (src))
3051         {
3052           tree fn = implicit_built_in_decls[BUILT_IN_MEMCPY];
3053           if (!fn)
3054             return 0;
3055           fn = build_function_call_expr (fn, arglist);
3056           if (TREE_CODE (fn) == CALL_EXPR)
3057             CALL_EXPR_TAILCALL (fn) = CALL_EXPR_TAILCALL (orig_exp);
3058           return expand_expr (fn, target, mode, EXPAND_NORMAL);
3059         }
3060
3061       /* If length is 1 and we can expand memcpy call inline,
3062          it is ok to use memcpy as well.  */
3063       if (integer_onep (len))
3064         {
3065           rtx ret = expand_builtin_mempcpy (arglist, type, target, mode,
3066                                             /*endp=*/0);
3067           if (ret)
3068             return ret;
3069         }
3070
3071       /* Otherwise, call the normal function.  */
3072       return 0;
3073    }
3074 }
3075
3076 /* Expand expression EXP, which is a call to the bcopy builtin.  Return 0
3077    if we failed the caller should emit a normal call.  */
3078
3079 static rtx
3080 expand_builtin_bcopy (tree exp)
3081 {
3082   tree arglist = TREE_OPERAND (exp, 1);
3083   tree type = TREE_TYPE (exp);
3084   tree src, dest, size, newarglist;
3085
3086   if (!validate_arglist (arglist,
3087                          POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
3088     return NULL_RTX;
3089
3090   src = TREE_VALUE (arglist);
3091   dest = TREE_VALUE (TREE_CHAIN (arglist));
3092   size = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
3093
3094   /* New argument list transforming bcopy(ptr x, ptr y, int z) to
3095      memmove(ptr y, ptr x, size_t z).   This is done this way
3096      so that if it isn't expanded inline, we fallback to
3097      calling bcopy instead of memmove.  */
3098
3099   newarglist = build_tree_list (NULL_TREE, fold_convert (sizetype, size));
3100   newarglist = tree_cons (NULL_TREE, src, newarglist);
3101   newarglist = tree_cons (NULL_TREE, dest, newarglist);
3102
3103   return expand_builtin_memmove (newarglist, type, const0_rtx, VOIDmode, exp);
3104 }
3105
3106 #ifndef HAVE_movstr
3107 # define HAVE_movstr 0
3108 # define CODE_FOR_movstr CODE_FOR_nothing
3109 #endif
3110
3111 /* Expand into a movstr instruction, if one is available.  Return 0 if
3112    we failed, the caller should emit a normal call, otherwise try to
3113    get the result in TARGET, if convenient.  If ENDP is 0 return the
3114    destination pointer, if ENDP is 1 return the end pointer ala
3115    mempcpy, and if ENDP is 2 return the end pointer minus one ala
3116    stpcpy.  */
3117
3118 static rtx
3119 expand_movstr (tree dest, tree src, rtx target, int endp)
3120 {
3121   rtx end;
3122   rtx dest_mem;
3123   rtx src_mem;
3124   rtx insn;
3125   const struct insn_data * data;
3126
3127   if (!HAVE_movstr)
3128     return 0;
3129
3130   dest_mem = get_memory_rtx (dest, NULL);
3131   src_mem = get_memory_rtx (src, NULL);
3132   if (!endp)
3133     {
3134       target = force_reg (Pmode, XEXP (dest_mem, 0));
3135       dest_mem = replace_equiv_address (dest_mem, target);
3136       end = gen_reg_rtx (Pmode);
3137     }
3138   else
3139     {
3140       if (target == 0 || target == const0_rtx)
3141         {
3142           end = gen_reg_rtx (Pmode);
3143           if (target == 0)
3144             target = end;
3145         }
3146       else
3147         end = target;
3148     }
3149
3150   data = insn_data + CODE_FOR_movstr;
3151
3152   if (data->operand[0].mode != VOIDmode)
3153     end = gen_lowpart (data->operand[0].mode, end);
3154
3155   insn = data->genfun (end, dest_mem, src_mem);
3156
3157   gcc_assert (insn);
3158
3159   emit_insn (insn);
3160
3161   /* movstr is supposed to set end to the address of the NUL
3162      terminator.  If the caller requested a mempcpy-like return value,
3163      adjust it.  */
3164   if (endp == 1 && target != const0_rtx)
3165     {
3166       rtx tem = plus_constant (gen_lowpart (GET_MODE (target), end), 1);
3167       emit_move_insn (target, force_operand (tem, NULL_RTX));
3168     }
3169
3170   return target;
3171 }
3172
3173 /* Expand expression EXP, which is a call to the strcpy builtin.  Return 0
3174    if we failed the caller should emit a normal call, otherwise try to get
3175    the result in TARGET, if convenient (and in mode MODE if that's
3176    convenient).  */
3177
3178 static rtx
3179 expand_builtin_strcpy (tree fndecl, tree arglist, rtx target, enum machine_mode mode)
3180 {
3181   if (validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
3182     {
3183       tree result = fold_builtin_strcpy (fndecl, arglist, 0);
3184       if (result)
3185         return expand_expr (result, target, mode, EXPAND_NORMAL);
3186
3187       return expand_movstr (TREE_VALUE (arglist),
3188                             TREE_VALUE (TREE_CHAIN (arglist)),
3189                             target, /*endp=*/0);
3190     }
3191   return 0;
3192 }
3193
3194 /* Expand a call to the stpcpy builtin, with arguments in ARGLIST.
3195    Return 0 if we failed the caller should emit a normal call,
3196    otherwise try to get the result in TARGET, if convenient (and in
3197    mode MODE if that's convenient).  */
3198
3199 static rtx
3200 expand_builtin_stpcpy (tree exp, rtx target, enum machine_mode mode)
3201 {
3202   tree arglist = TREE_OPERAND (exp, 1);
3203   /* If return value is ignored, transform stpcpy into strcpy.  */
3204   if (target == const0_rtx)
3205     {
3206       tree fn = implicit_built_in_decls[BUILT_IN_STRCPY];
3207       if (!fn)
3208         return 0;
3209
3210       return expand_expr (build_function_call_expr (fn, arglist),
3211                           target, mode, EXPAND_NORMAL);
3212     }
3213
3214   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
3215     return 0;
3216   else
3217     {
3218       tree dst, src, len, lenp1;
3219       tree narglist;
3220       rtx ret;
3221
3222       /* Ensure we get an actual string whose length can be evaluated at
3223          compile-time, not an expression containing a string.  This is
3224          because the latter will potentially produce pessimized code
3225          when used to produce the return value.  */
3226       src = TREE_VALUE (TREE_CHAIN (arglist));
3227       if (! c_getstr (src) || ! (len = c_strlen (src, 0)))
3228         return expand_movstr (TREE_VALUE (arglist),
3229                               TREE_VALUE (TREE_CHAIN (arglist)),
3230                               target, /*endp=*/2);
3231
3232       dst = TREE_VALUE (arglist);
3233       lenp1 = size_binop (PLUS_EXPR, len, ssize_int (1));
3234       narglist = build_tree_list (NULL_TREE, lenp1);
3235       narglist = tree_cons (NULL_TREE, src, narglist);
3236       narglist = tree_cons (NULL_TREE, dst, narglist);
3237       ret = expand_builtin_mempcpy (narglist, TREE_TYPE (exp),
3238                                     target, mode, /*endp=*/2);
3239
3240       if (ret)
3241         return ret;
3242
3243       if (TREE_CODE (len) == INTEGER_CST)
3244         {
3245           rtx len_rtx = expand_expr (len, NULL_RTX, VOIDmode, 0);
3246
3247           if (GET_CODE (len_rtx) == CONST_INT)
3248             {
3249               ret = expand_builtin_strcpy (get_callee_fndecl (exp),
3250                                            arglist, target, mode);
3251
3252               if (ret)
3253                 {
3254                   if (! target)
3255                     {
3256                       if (mode != VOIDmode)
3257                         target = gen_reg_rtx (mode);
3258                       else
3259                         target = gen_reg_rtx (GET_MODE (ret));
3260                     }
3261                   if (GET_MODE (target) != GET_MODE (ret))
3262                     ret = gen_lowpart (GET_MODE (target), ret);
3263
3264                   ret = plus_constant (ret, INTVAL (len_rtx));
3265                   ret = emit_move_insn (target, force_operand (ret, NULL_RTX));
3266                   gcc_assert (ret);
3267
3268                   return target;
3269                 }
3270             }
3271         }
3272
3273       return expand_movstr (TREE_VALUE (arglist),
3274                             TREE_VALUE (TREE_CHAIN (arglist)),
3275                             target, /*endp=*/2);
3276     }
3277 }
3278
3279 /* Callback routine for store_by_pieces.  Read GET_MODE_BITSIZE (MODE)
3280    bytes from constant string DATA + OFFSET and return it as target
3281    constant.  */
3282
3283 static rtx
3284 builtin_strncpy_read_str (void *data, HOST_WIDE_INT offset,
3285                           enum machine_mode mode)
3286 {
3287   const char *str = (const char *) data;
3288
3289   if ((unsigned HOST_WIDE_INT) offset > strlen (str))
3290     return const0_rtx;
3291
3292   return c_readstr (str + offset, mode);
3293 }
3294
3295 /* Expand expression EXP, which is a call to the strncpy builtin.  Return 0
3296    if we failed the caller should emit a normal call.  */
3297
3298 static rtx
3299 expand_builtin_strncpy (tree exp, rtx target, enum machine_mode mode)
3300 {
3301   tree fndecl = get_callee_fndecl (exp);
3302   tree arglist = TREE_OPERAND (exp, 1);
3303   if (validate_arglist (arglist,
3304                         POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
3305     {
3306       tree slen = c_strlen (TREE_VALUE (TREE_CHAIN (arglist)), 1);
3307       tree len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
3308       tree result = fold_builtin_strncpy (fndecl, arglist, slen);
3309
3310       if (result)
3311         return expand_expr (result, target, mode, EXPAND_NORMAL);
3312
3313       /* We must be passed a constant len and src parameter.  */
3314       if (!host_integerp (len, 1) || !slen || !host_integerp (slen, 1))
3315         return 0;
3316
3317       slen = size_binop (PLUS_EXPR, slen, ssize_int (1));
3318
3319       /* We're required to pad with trailing zeros if the requested
3320          len is greater than strlen(s2)+1.  In that case try to
3321          use store_by_pieces, if it fails, punt.  */
3322       if (tree_int_cst_lt (slen, len))
3323         {
3324           tree dest = TREE_VALUE (arglist);
3325           unsigned int dest_align
3326             = get_pointer_alignment (dest, BIGGEST_ALIGNMENT);
3327           const char *p = c_getstr (TREE_VALUE (TREE_CHAIN (arglist)));
3328           rtx dest_mem;
3329
3330           if (!p || dest_align == 0 || !host_integerp (len, 1)
3331               || !can_store_by_pieces (tree_low_cst (len, 1),
3332                                        builtin_strncpy_read_str,
3333                                        (void *) p, dest_align))
3334             return 0;
3335
3336           dest_mem = get_memory_rtx (dest, len);
3337           store_by_pieces (dest_mem, tree_low_cst (len, 1),
3338                            builtin_strncpy_read_str,
3339                            (void *) p, dest_align, 0);
3340           dest_mem = force_operand (XEXP (dest_mem, 0), NULL_RTX);
3341           dest_mem = convert_memory_address (ptr_mode, dest_mem);
3342           return dest_mem;
3343         }
3344     }
3345   return 0;
3346 }
3347
3348 /* Callback routine for store_by_pieces.  Read GET_MODE_BITSIZE (MODE)
3349    bytes from constant string DATA + OFFSET and return it as target
3350    constant.  */
3351
3352 static rtx
3353 builtin_memset_read_str (void *data, HOST_WIDE_INT offset ATTRIBUTE_UNUSED,
3354                          enum machine_mode mode)
3355 {
3356   const char *c = (const char *) data;
3357   char *p = alloca (GET_MODE_SIZE (mode));
3358
3359   memset (p, *c, GET_MODE_SIZE (mode));
3360
3361   return c_readstr (p, mode);
3362 }
3363
3364 /* Callback routine for store_by_pieces.  Return the RTL of a register
3365    containing GET_MODE_SIZE (MODE) consecutive copies of the unsigned
3366    char value given in the RTL register data.  For example, if mode is
3367    4 bytes wide, return the RTL for 0x01010101*data.  */
3368
3369 static rtx
3370 builtin_memset_gen_str (void *data, HOST_WIDE_INT offset ATTRIBUTE_UNUSED,
3371                         enum machine_mode mode)
3372 {
3373   rtx target, coeff;
3374   size_t size;
3375   char *p;
3376
3377   size = GET_MODE_SIZE (mode);
3378   if (size == 1)
3379     return (rtx) data;
3380
3381   p = alloca (size);
3382   memset (p, 1, size);
3383   coeff = c_readstr (p, mode);
3384
3385   target = convert_to_mode (mode, (rtx) data, 1);
3386   target = expand_mult (mode, target, coeff, NULL_RTX, 1);
3387   return force_reg (mode, target);
3388 }
3389
3390 /* Expand expression EXP, which is a call to the memset builtin.  Return 0
3391    if we failed the caller should emit a normal call, otherwise try to get
3392    the result in TARGET, if convenient (and in mode MODE if that's
3393    convenient).  */
3394
3395 static rtx
3396 expand_builtin_memset (tree arglist, rtx target, enum machine_mode mode,
3397                        tree orig_exp)
3398 {
3399   if (!validate_arglist (arglist,
3400                          POINTER_TYPE, INTEGER_TYPE, INTEGER_TYPE, VOID_TYPE))
3401     return 0;
3402   else
3403     {
3404       tree dest = TREE_VALUE (arglist);
3405       tree val = TREE_VALUE (TREE_CHAIN (arglist));
3406       tree len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
3407       char c;
3408
3409       unsigned int dest_align
3410         = get_pointer_alignment (dest, BIGGEST_ALIGNMENT);
3411       rtx dest_mem, dest_addr, len_rtx;
3412
3413       /* If DEST is not a pointer type, don't do this
3414          operation in-line.  */
3415       if (dest_align == 0)
3416         return 0;
3417
3418       /* If the LEN parameter is zero, return DEST.  */
3419       if (integer_zerop (len))
3420         {
3421           /* Evaluate and ignore VAL in case it has side-effects.  */
3422           expand_expr (val, const0_rtx, VOIDmode, EXPAND_NORMAL);
3423           return expand_expr (dest, target, mode, EXPAND_NORMAL);
3424         }
3425
3426       len_rtx = expand_expr (len, NULL_RTX, VOIDmode, 0);
3427       dest_mem = get_memory_rtx (dest, len);
3428
3429       if (TREE_CODE (val) != INTEGER_CST)
3430         {
3431           rtx val_rtx;
3432
3433           val = fold_build1 (CONVERT_EXPR, unsigned_char_type_node, val);
3434           val_rtx = expand_expr (val, NULL_RTX, VOIDmode, 0);
3435
3436           /* Assume that we can memset by pieces if we can store the
3437            * the coefficients by pieces (in the required modes).
3438            * We can't pass builtin_memset_gen_str as that emits RTL.  */
3439           c = 1;
3440           if (host_integerp (len, 1)
3441               && !(optimize_size && tree_low_cst (len, 1) > 1)
3442               && can_store_by_pieces (tree_low_cst (len, 1),
3443                                       builtin_memset_read_str, &c, dest_align))
3444             {
3445               val_rtx = force_reg (TYPE_MODE (unsigned_char_type_node),
3446                                    val_rtx);
3447               store_by_pieces (dest_mem, tree_low_cst (len, 1),
3448                                builtin_memset_gen_str, val_rtx, dest_align, 0);
3449             }
3450           else if (!set_storage_via_setmem(dest_mem, len_rtx, val_rtx,
3451                                            dest_align))
3452             return 0;
3453
3454           dest_mem = force_operand (XEXP (dest_mem, 0), NULL_RTX);
3455           dest_mem = convert_memory_address (ptr_mode, dest_mem);
3456           return dest_mem;
3457         }
3458
3459       if (target_char_cast (val, &c))
3460         return 0;
3461
3462       if (c)
3463         {
3464           if (host_integerp (len, 1)
3465               && !(optimize_size && tree_low_cst (len, 1) > 1)
3466               && can_store_by_pieces (tree_low_cst (len, 1),
3467                                       builtin_memset_read_str, &c, dest_align))
3468             store_by_pieces (dest_mem, tree_low_cst (len, 1),
3469                              builtin_memset_read_str, &c, dest_align, 0);
3470           else if (!set_storage_via_setmem (dest_mem, len_rtx, GEN_INT (c),
3471                                             dest_align))
3472             return 0;
3473
3474           dest_mem = force_operand (XEXP (dest_mem, 0), NULL_RTX);
3475           dest_mem = convert_memory_address (ptr_mode, dest_mem);
3476           return dest_mem;
3477         }
3478
3479       set_mem_align (dest_mem, dest_align);
3480       dest_addr = clear_storage (dest_mem, len_rtx,
3481                                  CALL_EXPR_TAILCALL (orig_exp)
3482                                  ? BLOCK_OP_TAILCALL : BLOCK_OP_NORMAL);
3483
3484       if (dest_addr == 0)
3485         {
3486           dest_addr = force_operand (XEXP (dest_mem, 0), NULL_RTX);
3487           dest_addr = convert_memory_address (ptr_mode, dest_addr);
3488         }
3489
3490       return dest_addr;
3491     }
3492 }
3493
3494 /* Expand expression EXP, which is a call to the bzero builtin.  Return 0
3495    if we failed the caller should emit a normal call.  */
3496
3497 static rtx
3498 expand_builtin_bzero (tree exp)
3499 {
3500   tree arglist = TREE_OPERAND (exp, 1);
3501   tree dest, size, newarglist;
3502
3503   if (!validate_arglist (arglist, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
3504     return NULL_RTX;
3505
3506   dest = TREE_VALUE (arglist);
3507   size = TREE_VALUE (TREE_CHAIN (arglist));
3508
3509   /* New argument list transforming bzero(ptr x, int y) to
3510      memset(ptr x, int 0, size_t y).   This is done this way
3511      so that if it isn't expanded inline, we fallback to
3512      calling bzero instead of memset.  */
3513
3514   newarglist = build_tree_list (NULL_TREE, fold_convert (sizetype, size));
3515   newarglist = tree_cons (NULL_TREE, integer_zero_node, newarglist);
3516   newarglist = tree_cons (NULL_TREE, dest, newarglist);
3517
3518   return expand_builtin_memset (newarglist, const0_rtx, VOIDmode, exp);
3519 }
3520
3521 /* Expand expression EXP, which is a call to the memcmp built-in function.
3522    ARGLIST is the argument list for this call.  Return 0 if we failed and the
3523    caller should emit a normal call, otherwise try to get the result in
3524    TARGET, if convenient (and in mode MODE, if that's convenient).  */
3525
3526 static rtx
3527 expand_builtin_memcmp (tree exp ATTRIBUTE_UNUSED, tree arglist, rtx target,
3528                        enum machine_mode mode)
3529 {
3530   if (!validate_arglist (arglist,
3531                          POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
3532     return 0;
3533   else
3534     {
3535       tree result = fold_builtin_memcmp (arglist);
3536       if (result)
3537         return expand_expr (result, target, mode, EXPAND_NORMAL);
3538     }
3539
3540 #if defined HAVE_cmpmemsi || defined HAVE_cmpstrnsi
3541   {
3542     tree arg1 = TREE_VALUE (arglist);
3543     tree arg2 = TREE_VALUE (TREE_CHAIN (arglist));
3544     tree len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
3545     rtx arg1_rtx, arg2_rtx, arg3_rtx;
3546     rtx result;
3547     rtx insn;
3548
3549     int arg1_align
3550       = get_pointer_alignment (arg1, BIGGEST_ALIGNMENT) / BITS_PER_UNIT;
3551     int arg2_align
3552       = get_pointer_alignment (arg2, BIGGEST_ALIGNMENT) / BITS_PER_UNIT;
3553     enum machine_mode insn_mode;
3554
3555 #ifdef HAVE_cmpmemsi
3556     if (HAVE_cmpmemsi)
3557       insn_mode = insn_data[(int) CODE_FOR_cmpmemsi].operand[0].mode;
3558     else
3559 #endif
3560 #ifdef HAVE_cmpstrnsi
3561     if (HAVE_cmpstrnsi)
3562       insn_mode = insn_data[(int) CODE_FOR_cmpstrnsi].operand[0].mode;
3563     else
3564 #endif
3565       return 0;
3566
3567     /* If we don't have POINTER_TYPE, call the function.  */
3568     if (arg1_align == 0 || arg2_align == 0)
3569       return 0;
3570
3571     /* Make a place to write the result of the instruction.  */
3572     result = target;
3573     if (! (result != 0
3574            && REG_P (result) && GET_MODE (result) == insn_mode
3575            && REGNO (result) >= FIRST_PSEUDO_REGISTER))
3576       result = gen_reg_rtx (insn_mode);
3577
3578     arg1_rtx = get_memory_rtx (arg1, len);
3579     arg2_rtx = get_memory_rtx (arg2, len);
3580     arg3_rtx = expand_expr (len, NULL_RTX, VOIDmode, 0);
3581
3582     /* Set MEM_SIZE as appropriate.  */
3583     if (GET_CODE (arg3_rtx) == CONST_INT)
3584       {
3585         set_mem_size (arg1_rtx, arg3_rtx);
3586         set_mem_size (arg2_rtx, arg3_rtx);
3587       }
3588
3589 #ifdef HAVE_cmpmemsi
3590     if (HAVE_cmpmemsi)
3591       insn = gen_cmpmemsi (result, arg1_rtx, arg2_rtx, arg3_rtx,
3592                            GEN_INT (MIN (arg1_align, arg2_align)));
3593     else
3594 #endif
3595 #ifdef HAVE_cmpstrnsi
3596     if (HAVE_cmpstrnsi)
3597       insn = gen_cmpstrnsi (result, arg1_rtx, arg2_rtx, arg3_rtx,
3598                             GEN_INT (MIN (arg1_align, arg2_align)));
3599     else
3600 #endif
3601       gcc_unreachable ();
3602
3603     if (insn)
3604       emit_insn (insn);
3605     else
3606       emit_library_call_value (memcmp_libfunc, result, LCT_PURE_MAKE_BLOCK,
3607                                TYPE_MODE (integer_type_node), 3,
3608                                XEXP (arg1_rtx, 0), Pmode,
3609                                XEXP (arg2_rtx, 0), Pmode,
3610                                convert_to_mode (TYPE_MODE (sizetype), arg3_rtx,
3611                                                 TYPE_UNSIGNED (sizetype)),
3612                                TYPE_MODE (sizetype));
3613
3614     /* Return the value in the proper mode for this function.  */
3615     mode = TYPE_MODE (TREE_TYPE (exp));
3616     if (GET_MODE (result) == mode)
3617       return result;
3618     else if (target != 0)
3619       {
3620         convert_move (target, result, 0);
3621         return target;
3622       }
3623     else
3624       return convert_to_mode (mode, result, 0);
3625   }
3626 #endif
3627
3628   return 0;
3629 }
3630
3631 /* Expand expression EXP, which is a call to the strcmp builtin.  Return 0
3632    if we failed the caller should emit a normal call, otherwise try to get
3633    the result in TARGET, if convenient.  */
3634
3635 static rtx
3636 expand_builtin_strcmp (tree exp, rtx target, enum machine_mode mode)
3637 {
3638   tree arglist = TREE_OPERAND (exp, 1);
3639
3640   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
3641     return 0;
3642   else
3643     {
3644       tree result = fold_builtin_strcmp (arglist);
3645       if (result)
3646         return expand_expr (result, target, mode, EXPAND_NORMAL);
3647     }
3648
3649 #if defined HAVE_cmpstrsi || defined HAVE_cmpstrnsi
3650   if (cmpstr_optab[SImode] != CODE_FOR_nothing
3651       || cmpstrn_optab[SImode] != CODE_FOR_nothing)
3652     {
3653       rtx arg1_rtx, arg2_rtx;
3654       rtx result, insn = NULL_RTX;
3655       tree fndecl, fn;
3656
3657       tree arg1 = TREE_VALUE (arglist);
3658       tree arg2 = TREE_VALUE (TREE_CHAIN (arglist));
3659       int arg1_align
3660         = get_pointer_alignment (arg1, BIGGEST_ALIGNMENT) / BITS_PER_UNIT;
3661       int arg2_align
3662         = get_pointer_alignment (arg2, BIGGEST_ALIGNMENT) / BITS_PER_UNIT;
3663
3664       /* If we don't have POINTER_TYPE, call the function.  */
3665       if (arg1_align == 0 || arg2_align == 0)
3666         return 0;
3667
3668       /* Stabilize the arguments in case gen_cmpstr(n)si fail.  */
3669       arg1 = builtin_save_expr (arg1);
3670       arg2 = builtin_save_expr (arg2);
3671
3672       arg1_rtx = get_memory_rtx (arg1, NULL);
3673       arg2_rtx = get_memory_rtx (arg2, NULL);
3674
3675 #ifdef HAVE_cmpstrsi
3676       /* Try to call cmpstrsi.  */
3677       if (HAVE_cmpstrsi)
3678         {
3679           enum machine_mode insn_mode
3680             = insn_data[(int) CODE_FOR_cmpstrsi].operand[0].mode;
3681
3682           /* Make a place to write the result of the instruction.  */
3683           result = target;
3684           if (! (result != 0
3685                  && REG_P (result) && GET_MODE (result) == insn_mode
3686                  && REGNO (result) >= FIRST_PSEUDO_REGISTER))
3687             result = gen_reg_rtx (insn_mode);
3688
3689           insn = gen_cmpstrsi (result, arg1_rtx, arg2_rtx,
3690                                GEN_INT (MIN (arg1_align, arg2_align)));
3691         }
3692 #endif
3693 #if HAVE_cmpstrnsi
3694       /* Try to determine at least one length and call cmpstrnsi.  */
3695       if (!insn && HAVE_cmpstrnsi)
3696         {
3697           tree len;
3698           rtx arg3_rtx;
3699
3700           enum machine_mode insn_mode
3701             = insn_data[(int) CODE_FOR_cmpstrnsi].operand[0].mode;
3702           tree len1 = c_strlen (arg1, 1);
3703           tree len2 = c_strlen (arg2, 1);
3704
3705           if (len1)
3706             len1 = size_binop (PLUS_EXPR, ssize_int (1), len1);
3707           if (len2)
3708             len2 = size_binop (PLUS_EXPR, ssize_int (1), len2);
3709
3710           /* If we don't have a constant length for the first, use the length
3711              of the second, if we know it.  We don't require a constant for
3712              this case; some cost analysis could be done if both are available
3713              but neither is constant.  For now, assume they're equally cheap,
3714              unless one has side effects.  If both strings have constant lengths,
3715              use the smaller.  */
3716
3717           if (!len1)
3718             len = len2;
3719           else if (!len2)
3720             len = len1;
3721           else if (TREE_SIDE_EFFECTS (len1))
3722             len = len2;
3723           else if (TREE_SIDE_EFFECTS (len2))
3724             len = len1;
3725           else if (TREE_CODE (len1) != INTEGER_CST)
3726             len = len2;
3727           else if (TREE_CODE (len2) != INTEGER_CST)
3728             len = len1;
3729           else if (tree_int_cst_lt (len1, len2))
3730             len = len1;
3731           else
3732             len = len2;
3733
3734           /* If both arguments have side effects, we cannot optimize.  */
3735           if (!len || TREE_SIDE_EFFECTS (len))
3736             return 0;
3737
3738           /* Stabilize the arguments in case gen_cmpstrnsi fails.  */
3739           arg3_rtx = expand_expr (len, NULL_RTX, VOIDmode, 0);
3740
3741           /* Make a place to write the result of the instruction.  */
3742           result = target;
3743           if (! (result != 0
3744                  && REG_P (result) && GET_MODE (result) == insn_mode
3745                  && REGNO (result) >= FIRST_PSEUDO_REGISTER))
3746             result = gen_reg_rtx (insn_mode);
3747
3748           insn = gen_cmpstrnsi (result, arg1_rtx, arg2_rtx, arg3_rtx,
3749                                 GEN_INT (MIN (arg1_align, arg2_align)));
3750         }
3751 #endif
3752
3753       if (insn)
3754         {
3755           emit_insn (insn);
3756
3757           /* Return the value in the proper mode for this function.  */
3758           mode = TYPE_MODE (TREE_TYPE (exp));
3759           if (GET_MODE (result) == mode)
3760             return result;
3761           if (target == 0)
3762             return convert_to_mode (mode, result, 0);
3763           convert_move (target, result, 0);
3764           return target;
3765         }
3766
3767       /* Expand the library call ourselves using a stabilized argument
3768          list to avoid re-evaluating the function's arguments twice.  */
3769       arglist = build_tree_list (NULL_TREE, arg2);
3770       arglist = tree_cons (NULL_TREE, arg1, arglist);
3771       fndecl = get_callee_fndecl (exp);
3772       fn = build_function_call_expr (fndecl, arglist);
3773       if (TREE_CODE (fn) == CALL_EXPR)
3774         CALL_EXPR_TAILCALL (fn) = CALL_EXPR_TAILCALL (exp);
3775       return expand_call (fn, target, target == const0_rtx);
3776     }
3777 #endif
3778   return 0;
3779 }
3780
3781 /* Expand expression EXP, which is a call to the strncmp builtin.  Return 0
3782    if we failed the caller should emit a normal call, otherwise try to get
3783    the result in TARGET, if convenient.  */
3784
3785 static rtx
3786 expand_builtin_strncmp (tree exp, rtx target, enum machine_mode mode)
3787 {
3788   tree arglist = TREE_OPERAND (exp, 1);
3789
3790   if (!validate_arglist (arglist,
3791                          POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
3792     return 0;
3793   else
3794     {
3795       tree result = fold_builtin_strncmp (arglist);
3796       if (result)
3797         return expand_expr (result, target, mode, EXPAND_NORMAL);
3798     }
3799
3800   /* If c_strlen can determine an expression for one of the string
3801      lengths, and it doesn't have side effects, then emit cmpstrnsi
3802      using length MIN(strlen(string)+1, arg3).  */
3803 #ifdef HAVE_cmpstrnsi
3804   if (HAVE_cmpstrnsi)
3805   {
3806     tree arg1 = TREE_VALUE (arglist);
3807     tree arg2 = TREE_VALUE (TREE_CHAIN (arglist));
3808     tree arg3 = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
3809     tree len, len1, len2;
3810     rtx arg1_rtx, arg2_rtx, arg3_rtx;
3811     rtx result, insn;
3812     tree fndecl, fn;
3813
3814     int arg1_align
3815       = get_pointer_alignment (arg1, BIGGEST_ALIGNMENT) / BITS_PER_UNIT;
3816     int arg2_align
3817       = get_pointer_alignment (arg2, BIGGEST_ALIGNMENT) / BITS_PER_UNIT;
3818     enum machine_mode insn_mode
3819       = insn_data[(int) CODE_FOR_cmpstrnsi].operand[0].mode;
3820
3821     len1 = c_strlen (arg1, 1);
3822     len2 = c_strlen (arg2, 1);
3823
3824     if (len1)
3825       len1 = size_binop (PLUS_EXPR, ssize_int (1), len1);
3826     if (len2)
3827       len2 = size_binop (PLUS_EXPR, ssize_int (1), len2);
3828
3829     /* If we don't have a constant length for the first, use the length
3830        of the second, if we know it.  We don't require a constant for
3831        this case; some cost analysis could be done if both are available
3832        but neither is constant.  For now, assume they're equally cheap,
3833        unless one has side effects.  If both strings have constant lengths,
3834        use the smaller.  */
3835
3836     if (!len1)
3837       len = len2;
3838     else if (!len2)
3839       len = len1;
3840     else if (TREE_SIDE_EFFECTS (len1))
3841       len = len2;
3842     else if (TREE_SIDE_EFFECTS (len2))
3843       len = len1;
3844     else if (TREE_CODE (len1) != INTEGER_CST)
3845       len = len2;
3846     else if (TREE_CODE (len2) != INTEGER_CST)
3847       len = len1;
3848     else if (tree_int_cst_lt (len1, len2))
3849       len = len1;
3850     else
3851       len = len2;
3852
3853     /* If both arguments have side effects, we cannot optimize.  */
3854     if (!len || TREE_SIDE_EFFECTS (len))
3855       return 0;
3856
3857     /* The actual new length parameter is MIN(len,arg3).  */
3858     len = fold_build2 (MIN_EXPR, TREE_TYPE (len), len,
3859                        fold_convert (TREE_TYPE (len), arg3));
3860
3861     /* If we don't have POINTER_TYPE, call the function.  */
3862     if (arg1_align == 0 || arg2_align == 0)
3863       return 0;
3864
3865     /* Make a place to write the result of the instruction.  */
3866     result = target;
3867     if (! (result != 0
3868            && REG_P (result) && GET_MODE (result) == insn_mode
3869            && REGNO (result) >= FIRST_PSEUDO_REGISTER))
3870       result = gen_reg_rtx (insn_mode);
3871
3872     /* Stabilize the arguments in case gen_cmpstrnsi fails.  */
3873     arg1 = builtin_save_expr (arg1);
3874     arg2 = builtin_save_expr (arg2);
3875     len = builtin_save_expr (len);
3876
3877     arg1_rtx = get_memory_rtx (arg1, len);
3878     arg2_rtx = get_memory_rtx (arg2, len);
3879     arg3_rtx = expand_expr (len, NULL_RTX, VOIDmode, 0);
3880     insn = gen_cmpstrnsi (result, arg1_rtx, arg2_rtx, arg3_rtx,
3881                           GEN_INT (MIN (arg1_align, arg2_align)));
3882     if (insn)
3883       {
3884         emit_insn (insn);
3885
3886         /* Return the value in the proper mode for this function.  */
3887         mode = TYPE_MODE (TREE_TYPE (exp));
3888         if (GET_MODE (result) == mode)
3889           return result;
3890         if (target == 0)
3891           return convert_to_mode (mode, result, 0);
3892         convert_move (target, result, 0);
3893         return target;
3894       }
3895
3896     /* Expand the library call ourselves using a stabilized argument
3897        list to avoid re-evaluating the function's arguments twice.  */
3898     arglist = build_tree_list (NULL_TREE, len);
3899     arglist = tree_cons (NULL_TREE, arg2, arglist);
3900     arglist = tree_cons (NULL_TREE, arg1, arglist);
3901     fndecl = get_callee_fndecl (exp);
3902     fn = build_function_call_expr (fndecl, arglist);
3903     if (TREE_CODE (fn) == CALL_EXPR)
3904       CALL_EXPR_TAILCALL (fn) = CALL_EXPR_TAILCALL (exp);
3905     return expand_call (fn, target, target == const0_rtx);
3906   }
3907 #endif
3908   return 0;
3909 }
3910
3911 /* Expand expression EXP, which is a call to the strcat builtin.
3912    Return 0 if we failed the caller should emit a normal call,
3913    otherwise try to get the result in TARGET, if convenient.  */
3914
3915 static rtx
3916 expand_builtin_strcat (tree fndecl, tree arglist, rtx target, enum machine_mode mode)
3917 {
3918   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
3919     return 0;
3920   else
3921     {
3922       tree dst = TREE_VALUE (arglist),
3923       src = TREE_VALUE (TREE_CHAIN (arglist));
3924       const char *p = c_getstr (src);
3925
3926       /* If the string length is zero, return the dst parameter.  */
3927       if (p && *p == '\0')
3928         return expand_expr (dst, target, mode, EXPAND_NORMAL);
3929
3930       if (!optimize_size)
3931         {
3932           /* See if we can store by pieces into (dst + strlen(dst)).  */
3933           tree newsrc, newdst,
3934             strlen_fn = implicit_built_in_decls[BUILT_IN_STRLEN];
3935           rtx insns;
3936
3937           /* Stabilize the argument list.  */
3938           newsrc = builtin_save_expr (src);
3939           if (newsrc != src)
3940             arglist = build_tree_list (NULL_TREE, newsrc);
3941           else
3942             arglist = TREE_CHAIN (arglist); /* Reusing arglist if safe.  */
3943
3944           dst = builtin_save_expr (dst);
3945
3946           start_sequence ();
3947
3948           /* Create strlen (dst).  */
3949           newdst =
3950             build_function_call_expr (strlen_fn,
3951                                       build_tree_list (NULL_TREE, dst));
3952           /* Create (dst + (cast) strlen (dst)).  */
3953           newdst = fold_convert (TREE_TYPE (dst), newdst);
3954           newdst = fold_build2 (PLUS_EXPR, TREE_TYPE (dst), dst, newdst);
3955
3956           newdst = builtin_save_expr (newdst);
3957           arglist = tree_cons (NULL_TREE, newdst, arglist);
3958
3959           if (!expand_builtin_strcpy (fndecl, arglist, target, mode))
3960             {
3961               end_sequence (); /* Stop sequence.  */
3962               return 0;
3963             }
3964
3965           /* Output the entire sequence.  */
3966           insns = get_insns ();
3967           end_sequence ();
3968           emit_insn (insns);
3969
3970           return expand_expr (dst, target, mode, EXPAND_NORMAL);
3971         }
3972
3973       return 0;
3974     }
3975 }
3976
3977 /* Expand expression EXP, which is a call to the strncat builtin.
3978    Return 0 if we failed the caller should emit a normal call,
3979    otherwise try to get the result in TARGET, if convenient.  */
3980
3981 static rtx
3982 expand_builtin_strncat (tree arglist, rtx target, enum machine_mode mode)
3983 {
3984   if (validate_arglist (arglist,
3985                         POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
3986     {
3987       tree result = fold_builtin_strncat (arglist);
3988       if (result)
3989         return expand_expr (result, target, mode, EXPAND_NORMAL);
3990     }
3991   return 0;
3992 }
3993
3994 /* Expand expression EXP, which is a call to the strspn builtin.
3995    Return 0 if we failed the caller should emit a normal call,
3996    otherwise try to get the result in TARGET, if convenient.  */
3997
3998 static rtx
3999 expand_builtin_strspn (tree arglist, rtx target, enum machine_mode mode)
4000 {
4001   if (validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
4002     {
4003       tree result = fold_builtin_strspn (arglist);
4004       if (result)
4005         return expand_expr (result, target, mode, EXPAND_NORMAL);
4006     }
4007   return 0;
4008 }
4009
4010 /* Expand expression EXP, which is a call to the strcspn builtin.
4011    Return 0 if we failed the caller should emit a normal call,
4012    otherwise try to get the result in TARGET, if convenient.  */
4013
4014 static rtx
4015 expand_builtin_strcspn (tree arglist, rtx target, enum machine_mode mode)
4016 {
4017   if (validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
4018     {
4019       tree result = fold_builtin_strcspn (arglist);
4020       if (result)
4021         return expand_expr (result, target, mode, EXPAND_NORMAL);
4022     }
4023   return 0;
4024 }
4025
4026 /* Expand a call to __builtin_saveregs, generating the result in TARGET,
4027    if that's convenient.  */
4028
4029 rtx
4030 expand_builtin_saveregs (void)
4031 {
4032   rtx val, seq;
4033
4034   /* Don't do __builtin_saveregs more than once in a function.
4035      Save the result of the first call and reuse it.  */
4036   if (saveregs_value != 0)
4037     return saveregs_value;
4038
4039   /* When this function is called, it means that registers must be
4040      saved on entry to this function.  So we migrate the call to the
4041      first insn of this function.  */
4042
4043   start_sequence ();
4044
4045   /* Do whatever the machine needs done in this case.  */
4046   val = targetm.calls.expand_builtin_saveregs ();
4047
4048   seq = get_insns ();
4049   end_sequence ();
4050
4051   saveregs_value = val;
4052
4053   /* Put the insns after the NOTE that starts the function.  If this
4054      is inside a start_sequence, make the outer-level insn chain current, so
4055      the code is placed at the start of the function.  */
4056   push_topmost_sequence ();
4057   emit_insn_after (seq, entry_of_function ());
4058   pop_topmost_sequence ();
4059
4060   return val;
4061 }
4062
4063 /* __builtin_args_info (N) returns word N of the arg space info
4064    for the current function.  The number and meanings of words
4065    is controlled by the definition of CUMULATIVE_ARGS.  */
4066
4067 static rtx
4068 expand_builtin_args_info (tree arglist)
4069 {
4070   int nwords = sizeof (CUMULATIVE_ARGS) / sizeof (int);
4071   int *word_ptr = (int *) &current_function_args_info;
4072
4073   gcc_assert (sizeof (CUMULATIVE_ARGS) % sizeof (int) == 0);
4074
4075   if (arglist != 0)
4076     {
4077       if (!host_integerp (TREE_VALUE (arglist), 0))
4078         error ("argument of %<__builtin_args_info%> must be constant");
4079       else
4080         {
4081           HOST_WIDE_INT wordnum = tree_low_cst (TREE_VALUE (arglist), 0);
4082
4083           if (wordnum < 0 || wordnum >= nwords)
4084             error ("argument of %<__builtin_args_info%> out of range");
4085           else
4086             return GEN_INT (word_ptr[wordnum]);
4087         }
4088     }
4089   else
4090     error ("missing argument in %<__builtin_args_info%>");
4091
4092   return const0_rtx;
4093 }
4094
4095 /* Expand a call to __builtin_next_arg.  */
4096
4097 static rtx
4098 expand_builtin_next_arg (void)
4099 {
4100   /* Checking arguments is already done in fold_builtin_next_arg
4101      that must be called before this function.  */
4102   return expand_binop (Pmode, add_optab,
4103                        current_function_internal_arg_pointer,
4104                        current_function_arg_offset_rtx,
4105                        NULL_RTX, 0, OPTAB_LIB_WIDEN);
4106 }
4107
4108 /* Make it easier for the backends by protecting the valist argument
4109    from multiple evaluations.  */
4110
4111 static tree
4112 stabilize_va_list (tree valist, int needs_lvalue)
4113 {
4114   if (TREE_CODE (va_list_type_node) == ARRAY_TYPE)
4115     {
4116       if (TREE_SIDE_EFFECTS (valist))
4117         valist = save_expr (valist);
4118
4119       /* For this case, the backends will be expecting a pointer to
4120          TREE_TYPE (va_list_type_node), but it's possible we've
4121          actually been given an array (an actual va_list_type_node).
4122          So fix it.  */
4123       if (TREE_CODE (TREE_TYPE (valist)) == ARRAY_TYPE)
4124         {
4125           tree p1 = build_pointer_type (TREE_TYPE (va_list_type_node));
4126           valist = build_fold_addr_expr_with_type (valist, p1);
4127         }
4128     }
4129   else
4130     {
4131       tree pt;
4132
4133       if (! needs_lvalue)
4134         {
4135           if (! TREE_SIDE_EFFECTS (valist))
4136             return valist;
4137
4138           pt = build_pointer_type (va_list_type_node);
4139           valist = fold_build1 (ADDR_EXPR, pt, valist);
4140           TREE_SIDE_EFFECTS (valist) = 1;
4141         }
4142
4143       if (TREE_SIDE_EFFECTS (valist))
4144         valist = save_expr (valist);
4145       valist = build_fold_indirect_ref (valist);
4146     }
4147
4148   return valist;
4149 }
4150
4151 /* The "standard" definition of va_list is void*.  */
4152
4153 tree
4154 std_build_builtin_va_list (void)
4155 {
4156   return ptr_type_node;
4157 }
4158
4159 /* The "standard" implementation of va_start: just assign `nextarg' to
4160    the variable.  */
4161
4162 void
4163 std_expand_builtin_va_start (tree valist, rtx nextarg)
4164 {
4165   tree t;
4166
4167   t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist,
4168               make_tree (ptr_type_node, nextarg));
4169   TREE_SIDE_EFFECTS (t) = 1;
4170
4171   expand_expr (t, const0_rtx, VOIDmode, EXPAND_NORMAL);
4172 }
4173
4174 /* Expand ARGLIST, from a call to __builtin_va_start.  */
4175
4176 static rtx
4177 expand_builtin_va_start (tree arglist)
4178 {
4179   rtx nextarg;
4180   tree chain, valist;
4181
4182   chain = TREE_CHAIN (arglist);
4183
4184   if (!chain)
4185     {
4186       error ("too few arguments to function %<va_start%>");
4187       return const0_rtx;
4188     }
4189
4190   if (fold_builtin_next_arg (chain))
4191     return const0_rtx;
4192
4193   nextarg = expand_builtin_next_arg ();
4194   valist = stabilize_va_list (TREE_VALUE (arglist), 1);
4195
4196 #ifdef EXPAND_BUILTIN_VA_START
4197   EXPAND_BUILTIN_VA_START (valist, nextarg);
4198 #else
4199   std_expand_builtin_va_start (valist, nextarg);
4200 #endif
4201
4202   return const0_rtx;
4203 }
4204
4205 /* The "standard" implementation of va_arg: read the value from the
4206    current (padded) address and increment by the (padded) size.  */
4207
4208 tree
4209 std_gimplify_va_arg_expr (tree valist, tree type, tree *pre_p, tree *post_p)
4210 {
4211   tree addr, t, type_size, rounded_size, valist_tmp;
4212   unsigned HOST_WIDE_INT align, boundary;
4213   bool indirect;
4214
4215 #ifdef ARGS_GROW_DOWNWARD
4216   /* All of the alignment and movement below is for args-grow-up machines.
4217      As of 2004, there are only 3 ARGS_GROW_DOWNWARD targets, and they all
4218      implement their own specialized gimplify_va_arg_expr routines.  */
4219   gcc_unreachable ();
4220 #endif
4221
4222   indirect = pass_by_reference (NULL, TYPE_MODE (type), type, false);
4223   if (indirect)
4224     type = build_pointer_type (type);
4225
4226   align = PARM_BOUNDARY / BITS_PER_UNIT;
4227   boundary = FUNCTION_ARG_BOUNDARY (TYPE_MODE (type), type) / BITS_PER_UNIT;
4228
4229   /* Hoist the valist value into a temporary for the moment.  */
4230   valist_tmp = get_initialized_tmp_var (valist, pre_p, NULL);
4231
4232   /* va_list pointer is aligned to PARM_BOUNDARY.  If argument actually
4233      requires greater alignment, we must perform dynamic alignment.  */
4234   if (boundary > align)
4235     {
4236       t = fold_convert (TREE_TYPE (valist), size_int (boundary - 1));
4237       t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist_tmp,
4238                   build2 (PLUS_EXPR, TREE_TYPE (valist), valist_tmp, t));
4239       gimplify_and_add (t, pre_p);
4240
4241       t = fold_convert (TREE_TYPE (valist), size_int (-boundary));
4242       t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist_tmp,
4243                   build2 (BIT_AND_EXPR, TREE_TYPE (valist), valist_tmp, t));
4244       gimplify_and_add (t, pre_p);
4245     }
4246   else
4247     boundary = align;
4248
4249   /* If the actual alignment is less than the alignment of the type,
4250      adjust the type accordingly so that we don't assume strict alignment
4251      when deferencing the pointer.  */
4252   boundary *= BITS_PER_UNIT;
4253   if (boundary < TYPE_ALIGN (type))
4254     {
4255       type = build_variant_type_copy (type);
4256       TYPE_ALIGN (type) = boundary;
4257     }
4258
4259   /* Compute the rounded size of the type.  */
4260   type_size = size_in_bytes (type);
4261   rounded_size = round_up (type_size, align);
4262
4263   /* Reduce rounded_size so it's sharable with the postqueue.  */
4264   gimplify_expr (&rounded_size, pre_p, post_p, is_gimple_val, fb_rvalue);
4265
4266   /* Get AP.  */
4267   addr = valist_tmp;
4268   if (PAD_VARARGS_DOWN && !integer_zerop (rounded_size))
4269     {
4270       /* Small args are padded downward.  */
4271       t = fold_build2 (GT_EXPR, sizetype, rounded_size, size_int (align));
4272       t = fold_build3 (COND_EXPR, sizetype, t, size_zero_node,
4273                        size_binop (MINUS_EXPR, rounded_size, type_size));
4274       t = fold_convert (TREE_TYPE (addr), t);
4275       addr = fold_build2 (PLUS_EXPR, TREE_TYPE (addr), addr, t);
4276     }
4277
4278   /* Compute new value for AP.  */
4279   t = fold_convert (TREE_TYPE (valist), rounded_size);
4280   t = build2 (PLUS_EXPR, TREE_TYPE (valist), valist_tmp, t);
4281   t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist, t);
4282   gimplify_and_add (t, pre_p);
4283
4284   addr = fold_convert (build_pointer_type (type), addr);
4285
4286   if (indirect)
4287     addr = build_va_arg_indirect_ref (addr);
4288
4289   return build_va_arg_indirect_ref (addr);
4290 }
4291
4292 /* Build an indirect-ref expression over the given TREE, which represents a
4293    piece of a va_arg() expansion.  */
4294 tree
4295 build_va_arg_indirect_ref (tree addr)
4296 {
4297   addr = build_fold_indirect_ref (addr);
4298
4299   if (flag_mudflap) /* Don't instrument va_arg INDIRECT_REF.  */
4300     mf_mark (addr);
4301
4302   return addr;
4303 }
4304
4305 /* Return a dummy expression of type TYPE in order to keep going after an
4306    error.  */
4307
4308 static tree
4309 dummy_object (tree type)
4310 {
4311   tree t = convert (build_pointer_type (type), null_pointer_node);
4312   return build1 (INDIRECT_REF, type, t);
4313 }
4314
4315 /* Gimplify __builtin_va_arg, aka VA_ARG_EXPR, which is not really a
4316    builtin function, but a very special sort of operator.  */
4317
4318 enum gimplify_status
4319 gimplify_va_arg_expr (tree *expr_p, tree *pre_p, tree *post_p)
4320 {
4321   tree promoted_type, want_va_type, have_va_type;
4322   tree valist = TREE_OPERAND (*expr_p, 0);
4323   tree type = TREE_TYPE (*expr_p);
4324   tree t;
4325
4326   /* Verify that valist is of the proper type.  */
4327   want_va_type = va_list_type_node;
4328   have_va_type = TREE_TYPE (valist);
4329
4330   if (have_va_type == error_mark_node)
4331     return GS_ERROR;
4332
4333   if (TREE_CODE (want_va_type) == ARRAY_TYPE)
4334     {
4335       /* If va_list is an array type, the argument may have decayed
4336          to a pointer type, e.g. by being passed to another function.
4337          In that case, unwrap both types so that we can compare the
4338          underlying records.  */
4339       if (TREE_CODE (have_va_type) == ARRAY_TYPE
4340           || POINTER_TYPE_P (have_va_type))
4341         {
4342           want_va_type = TREE_TYPE (want_va_type);
4343           have_va_type = TREE_TYPE (have_va_type);
4344         }
4345     }
4346
4347   if (TYPE_MAIN_VARIANT (want_va_type) != TYPE_MAIN_VARIANT (have_va_type))
4348     {
4349       error ("first argument to %<va_arg%> not of type %<va_list%>");
4350       return GS_ERROR;
4351     }
4352
4353   /* Generate a diagnostic for requesting data of a type that cannot
4354      be passed through `...' due to type promotion at the call site.  */
4355   else if ((promoted_type = lang_hooks.types.type_promotes_to (type))
4356            != type)
4357     {
4358       static bool gave_help;
4359
4360       /* Unfortunately, this is merely undefined, rather than a constraint
4361          violation, so we cannot make this an error.  If this call is never
4362          executed, the program is still strictly conforming.  */
4363       warning (0, "%qT is promoted to %qT when passed through %<...%>",
4364                type, promoted_type);
4365       if (! gave_help)
4366         {
4367           gave_help = true;
4368           warning (0, "(so you should pass %qT not %qT to %<va_arg%>)",
4369                    promoted_type, type);
4370         }
4371
4372       /* We can, however, treat "undefined" any way we please.
4373          Call abort to encourage the user to fix the program.  */
4374       inform ("if this code is reached, the program will abort");
4375       t = build_function_call_expr (implicit_built_in_decls[BUILT_IN_TRAP],
4376                                     NULL);
4377       append_to_statement_list (t, pre_p);
4378
4379       /* This is dead code, but go ahead and finish so that the
4380          mode of the result comes out right.  */
4381       *expr_p = dummy_object (type);
4382       return GS_ALL_DONE;
4383     }
4384   else
4385     {
4386       /* Make it easier for the backends by protecting the valist argument
4387          from multiple evaluations.  */
4388       if (TREE_CODE (va_list_type_node) == ARRAY_TYPE)
4389         {
4390           /* For this case, the backends will be expecting a pointer to
4391              TREE_TYPE (va_list_type_node), but it's possible we've
4392              actually been given an array (an actual va_list_type_node).
4393              So fix it.  */
4394           if (TREE_CODE (TREE_TYPE (valist)) == ARRAY_TYPE)
4395             {
4396               tree p1 = build_pointer_type (TREE_TYPE (va_list_type_node));
4397               valist = build_fold_addr_expr_with_type (valist, p1);
4398             }
4399           gimplify_expr (&valist, pre_p, post_p, is_gimple_val, fb_rvalue);
4400         }
4401       else
4402         gimplify_expr (&valist, pre_p, post_p, is_gimple_min_lval, fb_lvalue);
4403
4404       if (!targetm.gimplify_va_arg_expr)
4405         /* FIXME:Once most targets are converted we should merely
4406            assert this is non-null.  */
4407         return GS_ALL_DONE;
4408
4409       *expr_p = targetm.gimplify_va_arg_expr (valist, type, pre_p, post_p);
4410       return GS_OK;
4411     }
4412 }
4413
4414 /* Expand ARGLIST, from a call to __builtin_va_end.  */
4415
4416 static rtx
4417 expand_builtin_va_end (tree arglist)
4418 {
4419   tree valist = TREE_VALUE (arglist);
4420
4421   /* Evaluate for side effects, if needed.  I hate macros that don't
4422      do that.  */
4423   if (TREE_SIDE_EFFECTS (valist))
4424     expand_expr (valist, const0_rtx, VOIDmode, EXPAND_NORMAL);
4425
4426   return const0_rtx;
4427 }
4428
4429 /* Expand ARGLIST, from a call to __builtin_va_copy.  We do this as a
4430    builtin rather than just as an assignment in stdarg.h because of the
4431    nastiness of array-type va_list types.  */
4432
4433 static rtx
4434 expand_builtin_va_copy (tree arglist)
4435 {
4436   tree dst, src, t;
4437
4438   dst = TREE_VALUE (arglist);
4439   src = TREE_VALUE (TREE_CHAIN (arglist));
4440
4441   dst = stabilize_va_list (dst, 1);
4442   src = stabilize_va_list (src, 0);
4443
4444   if (TREE_CODE (va_list_type_node) != ARRAY_TYPE)
4445     {
4446       t = build2 (MODIFY_EXPR, va_list_type_node, dst, src);
4447       TREE_SIDE_EFFECTS (t) = 1;
4448       expand_expr (t, const0_rtx, VOIDmode, EXPAND_NORMAL);
4449     }
4450   else
4451     {
4452       rtx dstb, srcb, size;
4453
4454       /* Evaluate to pointers.  */
4455       dstb = expand_expr (dst, NULL_RTX, Pmode, EXPAND_NORMAL);
4456       srcb = expand_expr (src, NULL_RTX, Pmode, EXPAND_NORMAL);
4457       size = expand_expr (TYPE_SIZE_UNIT (va_list_type_node), NULL_RTX,
4458                           VOIDmode, EXPAND_NORMAL);
4459
4460       dstb = convert_memory_address (Pmode, dstb);
4461       srcb = convert_memory_address (Pmode, srcb);
4462
4463       /* "Dereference" to BLKmode memories.  */
4464       dstb = gen_rtx_MEM (BLKmode, dstb);
4465       set_mem_alias_set (dstb, get_alias_set (TREE_TYPE (TREE_TYPE (dst))));
4466       set_mem_align (dstb, TYPE_ALIGN (va_list_type_node));
4467       srcb = gen_rtx_MEM (BLKmode, srcb);
4468       set_mem_alias_set (srcb, get_alias_set (TREE_TYPE (TREE_TYPE (src))));
4469       set_mem_align (srcb, TYPE_ALIGN (va_list_type_node));
4470
4471       /* Copy.  */
4472       emit_block_move (dstb, srcb, size, BLOCK_OP_NORMAL);
4473     }
4474
4475   return const0_rtx;
4476 }
4477
4478 /* Expand a call to one of the builtin functions __builtin_frame_address or
4479    __builtin_return_address.  */
4480
4481 static rtx
4482 expand_builtin_frame_address (tree fndecl, tree arglist)
4483 {
4484   /* The argument must be a nonnegative integer constant.
4485      It counts the number of frames to scan up the stack.
4486      The value is the return address saved in that frame.  */
4487   if (arglist == 0)
4488     /* Warning about missing arg was already issued.  */
4489     return const0_rtx;
4490   else if (! host_integerp (TREE_VALUE (arglist), 1))
4491     {
4492       if (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_FRAME_ADDRESS)
4493         error ("invalid argument to %<__builtin_frame_address%>");
4494       else
4495         error ("invalid argument to %<__builtin_return_address%>");
4496       return const0_rtx;
4497     }
4498   else
4499     {
4500       rtx tem
4501         = expand_builtin_return_addr (DECL_FUNCTION_CODE (fndecl),
4502                                       tree_low_cst (TREE_VALUE (arglist), 1));
4503
4504       /* Some ports cannot access arbitrary stack frames.  */
4505       if (tem == NULL)
4506         {
4507           if (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_FRAME_ADDRESS)
4508             warning (0, "unsupported argument to %<__builtin_frame_address%>");
4509           else
4510             warning (0, "unsupported argument to %<__builtin_return_address%>");
4511           return const0_rtx;
4512         }
4513
4514       /* For __builtin_frame_address, return what we've got.  */
4515       if (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_FRAME_ADDRESS)
4516         return tem;
4517
4518       if (!REG_P (tem)
4519           && ! CONSTANT_P (tem))
4520         tem = copy_to_mode_reg (Pmode, tem);
4521       return tem;
4522     }
4523 }
4524
4525 /* Expand a call to the alloca builtin, with arguments ARGLIST.  Return 0 if
4526    we failed and the caller should emit a normal call, otherwise try to get
4527    the result in TARGET, if convenient.  */
4528
4529 static rtx
4530 expand_builtin_alloca (tree arglist, rtx target)
4531 {
4532   rtx op0;
4533   rtx result;
4534
4535   /* In -fmudflap-instrumented code, alloca() and __builtin_alloca()
4536      should always expand to function calls.  These can be intercepted
4537      in libmudflap.  */
4538   if (flag_mudflap)
4539     return 0;
4540
4541   if (!validate_arglist (arglist, INTEGER_TYPE, VOID_TYPE))
4542     return 0;
4543
4544   /* Compute the argument.  */
4545   op0 = expand_expr (TREE_VALUE (arglist), NULL_RTX, VOIDmode, 0);
4546
4547   /* Allocate the desired space.  */
4548   result = allocate_dynamic_stack_space (op0, target, BITS_PER_UNIT);
4549   result = convert_memory_address (ptr_mode, result);
4550
4551   return result;
4552 }
4553
4554 /* Expand a call to a unary builtin.  The arguments are in ARGLIST.
4555    Return 0 if a normal call should be emitted rather than expanding the
4556    function in-line.  If convenient, the result should be placed in TARGET.
4557    SUBTARGET may be used as the target for computing one of EXP's operands.  */
4558
4559 static rtx
4560 expand_builtin_unop (enum machine_mode target_mode, tree arglist, rtx target,
4561                      rtx subtarget, optab op_optab)
4562 {
4563   rtx op0;
4564   if (!validate_arglist (arglist, INTEGER_TYPE, VOID_TYPE))
4565     return 0;
4566
4567   /* Compute the argument.  */
4568   op0 = expand_expr (TREE_VALUE (arglist), subtarget, VOIDmode, 0);
4569   /* Compute op, into TARGET if possible.
4570      Set TARGET to wherever the result comes back.  */
4571   target = expand_unop (TYPE_MODE (TREE_TYPE (TREE_VALUE (arglist))),
4572                         op_optab, op0, target, 1);
4573   gcc_assert (target);
4574
4575   return convert_to_mode (target_mode, target, 0);
4576 }
4577
4578 /* If the string passed to fputs is a constant and is one character
4579    long, we attempt to transform this call into __builtin_fputc().  */
4580
4581 static rtx
4582 expand_builtin_fputs (tree arglist, rtx target, bool unlocked)
4583 {
4584   /* Verify the arguments in the original call.  */
4585   if (validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
4586     {
4587       tree result = fold_builtin_fputs (arglist, (target == const0_rtx),
4588                                         unlocked, NULL_TREE);
4589       if (result)
4590         return expand_expr (result, target, VOIDmode, EXPAND_NORMAL);
4591     }
4592   return 0;
4593 }
4594
4595 /* Expand a call to __builtin_expect.  We return our argument and emit a
4596    NOTE_INSN_EXPECTED_VALUE note.  This is the expansion of __builtin_expect in
4597    a non-jump context.  */
4598
4599 static rtx
4600 expand_builtin_expect (tree arglist, rtx target)
4601 {
4602   tree exp, c;
4603   rtx note, rtx_c;
4604
4605   if (arglist == NULL_TREE
4606       || TREE_CHAIN (arglist) == NULL_TREE)
4607     return const0_rtx;
4608   exp = TREE_VALUE (arglist);
4609   c = TREE_VALUE (TREE_CHAIN (arglist));
4610
4611   if (TREE_CODE (c) != INTEGER_CST)
4612     {
4613       error ("second argument to %<__builtin_expect%> must be a constant");
4614       c = integer_zero_node;
4615     }
4616
4617   target = expand_expr (exp, target, VOIDmode, EXPAND_NORMAL);
4618
4619   /* Don't bother with expected value notes for integral constants.  */
4620   if (flag_guess_branch_prob && GET_CODE (target) != CONST_INT)
4621     {
4622       /* We do need to force this into a register so that we can be
4623          moderately sure to be able to correctly interpret the branch
4624          condition later.  */
4625       target = force_reg (GET_MODE (target), target);
4626
4627       rtx_c = expand_expr (c, NULL_RTX, GET_MODE (target), EXPAND_NORMAL);
4628
4629       note = emit_note (NOTE_INSN_EXPECTED_VALUE);
4630       NOTE_EXPECTED_VALUE (note) = gen_rtx_EQ (VOIDmode, target, rtx_c);
4631     }
4632
4633   return target;
4634 }
4635
4636 /* Like expand_builtin_expect, except do this in a jump context.  This is
4637    called from do_jump if the conditional is a __builtin_expect.  Return either
4638    a list of insns to emit the jump or NULL if we cannot optimize
4639    __builtin_expect.  We need to optimize this at jump time so that machines
4640    like the PowerPC don't turn the test into a SCC operation, and then jump
4641    based on the test being 0/1.  */
4642
4643 rtx
4644 expand_builtin_expect_jump (tree exp, rtx if_false_label, rtx if_true_label)
4645 {
4646   tree arglist = TREE_OPERAND (exp, 1);
4647   tree arg0 = TREE_VALUE (arglist);
4648   tree arg1 = TREE_VALUE (TREE_CHAIN (arglist));
4649   rtx ret = NULL_RTX;
4650
4651   /* Only handle __builtin_expect (test, 0) and
4652      __builtin_expect (test, 1).  */
4653   if (TREE_CODE (TREE_TYPE (arg1)) == INTEGER_TYPE
4654       && (integer_zerop (arg1) || integer_onep (arg1)))
4655     {
4656       rtx insn, drop_through_label, temp;
4657
4658       /* Expand the jump insns.  */
4659       start_sequence ();
4660       do_jump (arg0, if_false_label, if_true_label);
4661       ret = get_insns ();
4662
4663       drop_through_label = get_last_insn ();
4664       if (drop_through_label && NOTE_P (drop_through_label))
4665         drop_through_label = prev_nonnote_insn (drop_through_label);
4666       if (drop_through_label && !LABEL_P (drop_through_label))
4667         drop_through_label = NULL_RTX;
4668       end_sequence ();
4669
4670       if (! if_true_label)
4671         if_true_label = drop_through_label;
4672       if (! if_false_label)
4673         if_false_label = drop_through_label;
4674
4675       /* Go through and add the expect's to each of the conditional jumps.  */
4676       insn = ret;
4677       while (insn != NULL_RTX)
4678         {
4679           rtx next = NEXT_INSN (insn);
4680
4681           if (JUMP_P (insn) && any_condjump_p (insn))
4682             {
4683               rtx ifelse = SET_SRC (pc_set (insn));
4684               rtx then_dest = XEXP (ifelse, 1);
4685               rtx else_dest = XEXP (ifelse, 2);
4686               int taken = -1;
4687
4688               /* First check if we recognize any of the labels.  */
4689               if (GET_CODE (then_dest) == LABEL_REF
4690                   && XEXP (then_dest, 0) == if_true_label)
4691                 taken = 1;
4692               else if (GET_CODE (then_dest) == LABEL_REF
4693                        && XEXP (then_dest, 0) == if_false_label)
4694                 taken = 0;
4695               else if (GET_CODE (else_dest) == LABEL_REF
4696                        && XEXP (else_dest, 0) == if_false_label)
4697                 taken = 1;
4698               else if (GET_CODE (else_dest) == LABEL_REF
4699                        && XEXP (else_dest, 0) == if_true_label)
4700                 taken = 0;
4701               /* Otherwise check where we drop through.  */
4702               else if (else_dest == pc_rtx)
4703                 {
4704                   if (next && NOTE_P (next))
4705                     next = next_nonnote_insn (next);
4706
4707                   if (next && JUMP_P (next)
4708                       && any_uncondjump_p (next))
4709                     temp = XEXP (SET_SRC (pc_set (next)), 0);
4710                   else
4711                     temp = next;
4712
4713                   /* TEMP is either a CODE_LABEL, NULL_RTX or something
4714                      else that can't possibly match either target label.  */
4715                   if (temp == if_false_label)
4716                     taken = 1;
4717                   else if (temp == if_true_label)
4718                     taken = 0;
4719                 }
4720               else if (then_dest == pc_rtx)
4721                 {
4722                   if (next && NOTE_P (next))
4723                     next = next_nonnote_insn (next);
4724
4725                   if (next && JUMP_P (next)
4726                       && any_uncondjump_p (next))
4727                     temp = XEXP (SET_SRC (pc_set (next)), 0);
4728                   else
4729                     temp = next;
4730
4731                   if (temp == if_false_label)
4732                     taken = 0;
4733                   else if (temp == if_true_label)
4734                     taken = 1;
4735                 }
4736
4737               if (taken != -1)
4738                 {
4739                   /* If the test is expected to fail, reverse the
4740                      probabilities.  */
4741                   if (integer_zerop (arg1))
4742                     taken = 1 - taken;
4743                   predict_insn_def (insn, PRED_BUILTIN_EXPECT, taken);
4744                 }
4745             }
4746
4747           insn = next;
4748         }
4749     }
4750
4751   return ret;
4752 }
4753
4754 static void
4755 expand_builtin_trap (void)
4756 {
4757 #ifdef HAVE_trap
4758   if (HAVE_trap)
4759     emit_insn (gen_trap ());
4760   else
4761 #endif
4762     emit_library_call (abort_libfunc, LCT_NORETURN, VOIDmode, 0);
4763   emit_barrier ();
4764 }
4765
4766 /* Expand a call to fabs, fabsf or fabsl with arguments ARGLIST.
4767    Return 0 if a normal call should be emitted rather than expanding
4768    the function inline.  If convenient, the result should be placed
4769    in TARGET.  SUBTARGET may be used as the target for computing
4770    the operand.  */
4771
4772 static rtx
4773 expand_builtin_fabs (tree arglist, rtx target, rtx subtarget)
4774 {
4775   enum machine_mode mode;
4776   tree arg;
4777   rtx op0;
4778
4779   if (!validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
4780     return 0;
4781
4782   arg = TREE_VALUE (arglist);
4783   mode = TYPE_MODE (TREE_TYPE (arg));
4784   op0 = expand_expr (arg, subtarget, VOIDmode, 0);
4785   return expand_abs (mode, op0, target, 0, safe_from_p (target, arg, 1));
4786 }
4787
4788 /* Expand a call to copysign, copysignf, or copysignl with arguments ARGLIST.
4789    Return NULL is a normal call should be emitted rather than expanding the
4790    function inline.  If convenient, the result should be placed in TARGET.
4791    SUBTARGET may be used as the target for computing the operand.  */
4792
4793 static rtx
4794 expand_builtin_copysign (tree arglist, rtx target, rtx subtarget)
4795 {
4796   rtx op0, op1;
4797   tree arg;
4798
4799   if (!validate_arglist (arglist, REAL_TYPE, REAL_TYPE, VOID_TYPE))
4800     return 0;
4801
4802   arg = TREE_VALUE (arglist);
4803   op0 = expand_expr (arg, subtarget, VOIDmode, 0);
4804
4805   arg = TREE_VALUE (TREE_CHAIN (arglist));
4806   op1 = expand_expr (arg, NULL, VOIDmode, 0);
4807
4808   return expand_copysign (op0, op1, target);
4809 }
4810
4811 /* Create a new constant string literal and return a char* pointer to it.
4812    The STRING_CST value is the LEN characters at STR.  */
4813 static tree
4814 build_string_literal (int len, const char *str)
4815 {
4816   tree t, elem, index, type;
4817
4818   t = build_string (len, str);
4819   elem = build_type_variant (char_type_node, 1, 0);
4820   index = build_index_type (build_int_cst (NULL_TREE, len - 1));
4821   type = build_array_type (elem, index);
4822   TREE_TYPE (t) = type;
4823   TREE_CONSTANT (t) = 1;
4824   TREE_INVARIANT (t) = 1;
4825   TREE_READONLY (t) = 1;
4826   TREE_STATIC (t) = 1;
4827
4828   type = build_pointer_type (type);
4829   t = build1 (ADDR_EXPR, type, t);
4830
4831   type = build_pointer_type (elem);
4832   t = build1 (NOP_EXPR, type, t);
4833   return t;
4834 }
4835
4836 /* Expand EXP, a call to printf or printf_unlocked.
4837    Return 0 if a normal call should be emitted rather than transforming
4838    the function inline.  If convenient, the result should be placed in
4839    TARGET with mode MODE.  UNLOCKED indicates this is a printf_unlocked
4840    call.  */
4841 static rtx
4842 expand_builtin_printf (tree exp, rtx target, enum machine_mode mode,
4843                        bool unlocked)
4844 {
4845   tree arglist = TREE_OPERAND (exp, 1);
4846   tree fn_putchar = unlocked
4847                     ? implicit_built_in_decls[BUILT_IN_PUTCHAR_UNLOCKED]
4848                     : implicit_built_in_decls[BUILT_IN_PUTCHAR];
4849   tree fn_puts = unlocked ? implicit_built_in_decls[BUILT_IN_PUTS_UNLOCKED]
4850                           : implicit_built_in_decls[BUILT_IN_PUTS];
4851   const char *fmt_str;
4852   tree fn, fmt, arg;
4853
4854   /* If the return value is used, don't do the transformation.  */
4855   if (target != const0_rtx)
4856     return 0;
4857
4858   /* Verify the required arguments in the original call.  */
4859   if (! arglist)
4860     return 0;
4861   fmt = TREE_VALUE (arglist);
4862   if (! POINTER_TYPE_P (TREE_TYPE (fmt)))
4863     return 0;
4864   arglist = TREE_CHAIN (arglist);
4865
4866   /* Check whether the format is a literal string constant.  */
4867   fmt_str = c_getstr (fmt);
4868   if (fmt_str == NULL)
4869     return 0;
4870
4871   /* If the format specifier was "%s\n", call __builtin_puts(arg).  */
4872   if (strcmp (fmt_str, "%s\n") == 0)
4873     {
4874       if (! arglist
4875           || ! POINTER_TYPE_P (TREE_TYPE (TREE_VALUE (arglist)))
4876           || TREE_CHAIN (arglist))
4877         return 0;
4878       fn = fn_puts;
4879     }
4880   /* If the format specifier was "%c", call __builtin_putchar(arg).  */
4881   else if (strcmp (fmt_str, "%c") == 0)
4882     {
4883       if (! arglist
4884           || TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) != INTEGER_TYPE
4885           || TREE_CHAIN (arglist))
4886         return 0;
4887       fn = fn_putchar;
4888     }
4889   else
4890     {
4891       /* We can't handle anything else with % args or %% ... yet.  */
4892       if (strchr (fmt_str, '%'))
4893         return 0;
4894
4895       if (arglist)
4896         return 0;
4897
4898       /* If the format specifier was "", printf does nothing.  */
4899       if (fmt_str[0] == '\0')
4900         return const0_rtx;
4901       /* If the format specifier has length of 1, call putchar.  */
4902       if (fmt_str[1] == '\0')
4903         {
4904           /* Given printf("c"), (where c is any one character,)
4905              convert "c"[0] to an int and pass that to the replacement
4906              function.  */
4907           arg = build_int_cst (NULL_TREE, fmt_str[0]);
4908           arglist = build_tree_list (NULL_TREE, arg);
4909           fn = fn_putchar;
4910         }
4911       else
4912         {
4913           /* If the format specifier was "string\n", call puts("string").  */
4914           size_t len = strlen (fmt_str);
4915           if (fmt_str[len - 1] == '\n')
4916             {
4917               /* Create a NUL-terminated string that's one char shorter
4918                  than the original, stripping off the trailing '\n'.  */
4919               char *newstr = alloca (len);
4920               memcpy (newstr, fmt_str, len - 1);
4921               newstr[len - 1] = 0;
4922
4923               arg = build_string_literal (len, newstr);
4924               arglist = build_tree_list (NULL_TREE, arg);
4925               fn = fn_puts;
4926             }
4927           else
4928             /* We'd like to arrange to call fputs(string,stdout) here,
4929                but we need stdout and don't have a way to get it yet.  */
4930             return 0;
4931         }
4932     }
4933
4934   if (!fn)
4935     return 0;
4936   fn = build_function_call_expr (fn, arglist);
4937   if (TREE_CODE (fn) == CALL_EXPR)
4938     CALL_EXPR_TAILCALL (fn) = CALL_EXPR_TAILCALL (exp);
4939   return expand_expr (fn, target, mode, EXPAND_NORMAL);
4940 }
4941
4942 /* Expand EXP, a call to fprintf or fprintf_unlocked.
4943    Return 0 if a normal call should be emitted rather than transforming
4944    the function inline.  If convenient, the result should be placed in
4945    TARGET with mode MODE.  UNLOCKED indicates this is a fprintf_unlocked
4946    call.  */
4947 static rtx
4948 expand_builtin_fprintf (tree exp, rtx target, enum machine_mode mode,
4949                         bool unlocked)
4950 {
4951   tree arglist = TREE_OPERAND (exp, 1);
4952   tree fn_fputc = unlocked ? implicit_built_in_decls[BUILT_IN_FPUTC_UNLOCKED]
4953                            : implicit_built_in_decls[BUILT_IN_FPUTC];
4954   tree fn_fputs = unlocked ? implicit_built_in_decls[BUILT_IN_FPUTS_UNLOCKED]
4955                            : implicit_built_in_decls[BUILT_IN_FPUTS];
4956   const char *fmt_str;
4957   tree fn, fmt, fp, arg;
4958
4959   /* If the return value is used, don't do the transformation.  */
4960   if (target != const0_rtx)
4961     return 0;
4962
4963   /* Verify the required arguments in the original call.  */
4964   if (! arglist)
4965     return 0;
4966   fp = TREE_VALUE (arglist);
4967   if (! POINTER_TYPE_P (TREE_TYPE (fp)))
4968     return 0;
4969   arglist = TREE_CHAIN (arglist);
4970   if (! arglist)
4971     return 0;
4972   fmt = TREE_VALUE (arglist);
4973   if (! POINTER_TYPE_P (TREE_TYPE (fmt)))
4974     return 0;
4975   arglist = TREE_CHAIN (arglist);
4976
4977   /* Check whether the format is a literal string constant.  */
4978   fmt_str = c_getstr (fmt);
4979   if (fmt_str == NULL)
4980     return 0;
4981
4982   /* If the format specifier was "%s", call __builtin_fputs(arg,fp).  */
4983   if (strcmp (fmt_str, "%s") == 0)
4984     {
4985       if (! arglist
4986           || ! POINTER_TYPE_P (TREE_TYPE (TREE_VALUE (arglist)))
4987           || TREE_CHAIN (arglist))
4988         return 0;
4989       arg = TREE_VALUE (arglist);
4990       arglist = build_tree_list (NULL_TREE, fp);
4991       arglist = tree_cons (NULL_TREE, arg, arglist);
4992       fn = fn_fputs;
4993     }
4994   /* If the format specifier was "%c", call __builtin_fputc(arg,fp).  */
4995   else if (strcmp (fmt_str, "%c") == 0)
4996     {
4997       if (! arglist
4998           || TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) != INTEGER_TYPE
4999           || TREE_CHAIN (arglist))
5000         return 0;
5001       arg = TREE_VALUE (arglist);
5002       arglist = build_tree_list (NULL_TREE, fp);
5003       arglist = tree_cons (NULL_TREE, arg, arglist);
5004       fn = fn_fputc;
5005     }
5006   else
5007     {
5008       /* We can't handle anything else with % args or %% ... yet.  */
5009       if (strchr (fmt_str, '%'))
5010         return 0;
5011
5012       if (arglist)
5013         return 0;
5014
5015       /* If the format specifier was "", fprintf does nothing.  */
5016       if (fmt_str[0] == '\0')
5017         {
5018           /* Evaluate and ignore FILE* argument for side-effects.  */
5019           expand_expr (fp, const0_rtx, VOIDmode, EXPAND_NORMAL);
5020           return const0_rtx;
5021         }
5022
5023       /* When "string" doesn't contain %, replace all cases of
5024          fprintf(stream,string) with fputs(string,stream).  The fputs
5025          builtin will take care of special cases like length == 1.  */
5026       arglist = build_tree_list (NULL_TREE, fp);
5027       arglist = tree_cons (NULL_TREE, fmt, arglist);
5028       fn = fn_fputs;
5029     }
5030
5031   if (!fn)
5032     return 0;
5033   fn = build_function_call_expr (fn, arglist);
5034   if (TREE_CODE (fn) == CALL_EXPR)
5035     CALL_EXPR_TAILCALL (fn) = CALL_EXPR_TAILCALL (exp);
5036   return expand_expr (fn, target, mode, EXPAND_NORMAL);
5037 }
5038
5039 /* Expand a call to sprintf with argument list ARGLIST.  Return 0 if
5040    a normal call should be emitted rather than expanding the function
5041    inline.  If convenient, the result should be placed in TARGET with
5042    mode MODE.  */
5043
5044 static rtx
5045 expand_builtin_sprintf (tree arglist, rtx target, enum machine_mode mode)
5046 {
5047   tree orig_arglist, dest, fmt;
5048   const char *fmt_str;
5049
5050   orig_arglist = arglist;
5051
5052   /* Verify the required arguments in the original call.  */
5053   if (! arglist)
5054     return 0;
5055   dest = TREE_VALUE (arglist);
5056   if (! POINTER_TYPE_P (TREE_TYPE (dest)))
5057     return 0;
5058   arglist = TREE_CHAIN (arglist);
5059   if (! arglist)
5060     return 0;
5061   fmt = TREE_VALUE (arglist);
5062   if (! POINTER_TYPE_P (TREE_TYPE (fmt)))
5063     return 0;
5064   arglist = TREE_CHAIN (arglist);
5065
5066   /* Check whether the format is a literal string constant.  */
5067   fmt_str = c_getstr (fmt);
5068   if (fmt_str == NULL)
5069     return 0;
5070
5071   /* If the format doesn't contain % args or %%, use strcpy.  */
5072   if (strchr (fmt_str, '%') == 0)
5073     {
5074       tree fn = implicit_built_in_decls[BUILT_IN_STRCPY];
5075       tree exp;
5076
5077       if (arglist || ! fn)
5078         return 0;
5079       expand_expr (build_function_call_expr (fn, orig_arglist),
5080                    const0_rtx, VOIDmode, EXPAND_NORMAL);
5081       if (target == const0_rtx)
5082         return const0_rtx;
5083       exp = build_int_cst (NULL_TREE, strlen (fmt_str));
5084       return expand_expr (exp, target, mode, EXPAND_NORMAL);
5085     }
5086   /* If the format is "%s", use strcpy if the result isn't used.  */
5087   else if (strcmp (fmt_str, "%s") == 0)
5088     {
5089       tree fn, arg, len;
5090       fn = implicit_built_in_decls[BUILT_IN_STRCPY];
5091
5092       if (! fn)
5093         return 0;
5094
5095       if (! arglist || TREE_CHAIN (arglist))
5096         return 0;
5097       arg = TREE_VALUE (arglist);
5098       if (! POINTER_TYPE_P (TREE_TYPE (arg)))
5099         return 0;
5100
5101       if (target != const0_rtx)
5102         {
5103           len = c_strlen (arg, 1);
5104           if (! len || TREE_CODE (len) != INTEGER_CST)
5105             return 0;
5106         }
5107       else
5108         len = NULL_TREE;
5109
5110       arglist = build_tree_list (NULL_TREE, arg);
5111       arglist = tree_cons (NULL_TREE, dest, arglist);
5112       expand_expr (build_function_call_expr (fn, arglist),
5113                    const0_rtx, VOIDmode, EXPAND_NORMAL);
5114
5115       if (target == const0_rtx)
5116         return const0_rtx;
5117       return expand_expr (len, target, mode, EXPAND_NORMAL);
5118     }
5119
5120   return 0;
5121 }
5122
5123 /* Expand a call to either the entry or exit function profiler.  */
5124
5125 static rtx
5126 expand_builtin_profile_func (bool exitp)
5127 {
5128   rtx this, which;
5129
5130   this = DECL_RTL (current_function_decl);
5131   gcc_assert (MEM_P (this));
5132   this = XEXP (this, 0);
5133
5134   if (exitp)
5135     which = profile_function_exit_libfunc;
5136   else
5137     which = profile_function_entry_libfunc;
5138
5139   emit_library_call (which, LCT_NORMAL, VOIDmode, 2, this, Pmode,
5140                      expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
5141                                                  0),
5142                      Pmode);
5143
5144   return const0_rtx;
5145 }
5146
5147 /* Given a trampoline address, make sure it satisfies TRAMPOLINE_ALIGNMENT.  */
5148
5149 static rtx
5150 round_trampoline_addr (rtx tramp)
5151 {
5152   rtx temp, addend, mask;
5153
5154   /* If we don't need too much alignment, we'll have been guaranteed
5155      proper alignment by get_trampoline_type.  */
5156   if (TRAMPOLINE_ALIGNMENT <= STACK_BOUNDARY)
5157     return tramp;
5158
5159   /* Round address up to desired boundary.  */
5160   temp = gen_reg_rtx (Pmode);
5161   addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5162   mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5163
5164   temp  = expand_simple_binop (Pmode, PLUS, tramp, addend,
5165                                temp, 0, OPTAB_LIB_WIDEN);
5166   tramp = expand_simple_binop (Pmode, AND, temp, mask,
5167                                temp, 0, OPTAB_LIB_WIDEN);
5168
5169   return tramp;
5170 }
5171
5172 static rtx
5173 expand_builtin_init_trampoline (tree arglist)
5174 {
5175   tree t_tramp, t_func, t_chain;
5176   rtx r_tramp, r_func, r_chain;
5177 #ifdef TRAMPOLINE_TEMPLATE
5178   rtx blktramp;
5179 #endif
5180
5181   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE,
5182                          POINTER_TYPE, VOID_TYPE))
5183     return NULL_RTX;
5184
5185   t_tramp = TREE_VALUE (arglist);
5186   arglist = TREE_CHAIN (arglist);
5187   t_func = TREE_VALUE (arglist);
5188   arglist = TREE_CHAIN (arglist);
5189   t_chain = TREE_VALUE (arglist);
5190
5191   r_tramp = expand_expr (t_tramp, NULL_RTX, VOIDmode, 0);
5192   r_func = expand_expr (t_func, NULL_RTX, VOIDmode, 0);
5193   r_chain = expand_expr (t_chain, NULL_RTX, VOIDmode, 0);
5194
5195   /* Generate insns to initialize the trampoline.  */
5196   r_tramp = round_trampoline_addr (r_tramp);
5197 #ifdef TRAMPOLINE_TEMPLATE
5198   blktramp = gen_rtx_MEM (BLKmode, r_tramp);
5199   set_mem_align (blktramp, TRAMPOLINE_ALIGNMENT);
5200   emit_block_move (blktramp, assemble_trampoline_template (),
5201                    GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
5202 #endif
5203   trampolines_created = 1;
5204   INITIALIZE_TRAMPOLINE (r_tramp, r_func, r_chain);
5205
5206   return const0_rtx;
5207 }
5208
5209 static rtx
5210 expand_builtin_adjust_trampoline (tree arglist)
5211 {
5212   rtx tramp;
5213
5214   if (!validate_arglist (arglist, POINTER_TYPE, VOID_TYPE))
5215     return NULL_RTX;
5216
5217   tramp = expand_expr (TREE_VALUE (arglist), NULL_RTX, VOIDmode, 0);
5218   tramp = round_trampoline_addr (tramp);
5219 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5220   TRAMPOLINE_ADJUST_ADDRESS (tramp);
5221 #endif
5222
5223   return tramp;
5224 }
5225
5226 /* Expand a call to the built-in signbit, signbitf or signbitl function.
5227    Return NULL_RTX if a normal call should be emitted rather than expanding
5228    the function in-line.  EXP is the expression that is a call to the builtin
5229    function; if convenient, the result should be placed in TARGET.  */
5230
5231 static rtx
5232 expand_builtin_signbit (tree exp, rtx target)
5233 {
5234   const struct real_format *fmt;
5235   enum machine_mode fmode, imode, rmode;
5236   HOST_WIDE_INT hi, lo;
5237   tree arg, arglist;
5238   int word, bitpos;
5239   rtx temp;
5240
5241   arglist = TREE_OPERAND (exp, 1);
5242   if (!validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
5243     return 0;
5244
5245   arg = TREE_VALUE (arglist);
5246   fmode = TYPE_MODE (TREE_TYPE (arg));
5247   rmode = TYPE_MODE (TREE_TYPE (exp));
5248   fmt = REAL_MODE_FORMAT (fmode);
5249
5250   /* For floating point formats without a sign bit, implement signbit
5251      as "ARG < 0.0".  */
5252   bitpos = fmt->signbit_ro;
5253   if (bitpos < 0)
5254   {
5255     /* But we can't do this if the format supports signed zero.  */
5256     if (fmt->has_signed_zero && HONOR_SIGNED_ZEROS (fmode))
5257       return 0;
5258
5259     arg = fold_build2 (LT_EXPR, TREE_TYPE (exp), arg,
5260                        build_real (TREE_TYPE (arg), dconst0));
5261     return expand_expr (arg, target, VOIDmode, EXPAND_NORMAL);
5262   }
5263
5264   temp = expand_expr (arg, NULL_RTX, VOIDmode, 0);
5265   if (GET_MODE_SIZE (fmode) <= UNITS_PER_WORD)
5266     {
5267       imode = int_mode_for_mode (fmode);
5268       if (imode == BLKmode)
5269         return 0;
5270       temp = gen_lowpart (imode, temp);
5271     }
5272   else
5273     {
5274       imode = word_mode;
5275       /* Handle targets with different FP word orders.  */
5276       if (FLOAT_WORDS_BIG_ENDIAN)
5277         word = (GET_MODE_BITSIZE (fmode) - bitpos) / BITS_PER_WORD;
5278       else
5279         word = bitpos / BITS_PER_WORD;
5280       temp = operand_subword_force (temp, word, fmode);
5281       bitpos = bitpos % BITS_PER_WORD;
5282     }
5283
5284   /* Force the intermediate word_mode (or narrower) result into a
5285      register.  This avoids attempting to create paradoxical SUBREGs
5286      of floating point modes below.  */
5287   temp = force_reg (imode, temp);
5288
5289   /* If the bitpos is within the "result mode" lowpart, the operation
5290      can be implement with a single bitwise AND.  Otherwise, we need
5291      a right shift and an AND.  */
5292
5293   if (bitpos < GET_MODE_BITSIZE (rmode))
5294     {
5295       if (bitpos < HOST_BITS_PER_WIDE_INT)
5296         {
5297           hi = 0;
5298           lo = (HOST_WIDE_INT) 1 << bitpos;
5299         }
5300       else
5301         {
5302           hi = (HOST_WIDE_INT) 1 << (bitpos - HOST_BITS_PER_WIDE_INT);
5303           lo = 0;
5304         }
5305
5306       if (imode != rmode)
5307         temp = gen_lowpart (rmode, temp);
5308       temp = expand_binop (rmode, and_optab, temp,
5309                            immed_double_const (lo, hi, rmode),
5310                            NULL_RTX, 1, OPTAB_LIB_WIDEN);
5311     }
5312   else
5313     {
5314       /* Perform a logical right shift to place the signbit in the least
5315          significant bit, then truncate the result to the desired mode
5316          and mask just this bit.  */
5317       temp = expand_shift (RSHIFT_EXPR, imode, temp,
5318                            build_int_cst (NULL_TREE, bitpos), NULL_RTX, 1);
5319       temp = gen_lowpart (rmode, temp);
5320       temp = expand_binop (rmode, and_optab, temp, const1_rtx,
5321                            NULL_RTX, 1, OPTAB_LIB_WIDEN);
5322     }
5323
5324   return temp;
5325 }
5326
5327 /* Expand fork or exec calls.  TARGET is the desired target of the
5328    call.  ARGLIST is the list of arguments of the call.  FN is the
5329    identificator of the actual function.  IGNORE is nonzero if the
5330    value is to be ignored.  */
5331
5332 static rtx
5333 expand_builtin_fork_or_exec (tree fn, tree arglist, rtx target, int ignore)
5334 {
5335   tree id, decl;
5336   tree call;
5337
5338   /* If we are not profiling, just call the function.  */
5339   if (!profile_arc_flag)
5340     return NULL_RTX;
5341
5342   /* Otherwise call the wrapper.  This should be equivalent for the rest of
5343      compiler, so the code does not diverge, and the wrapper may run the
5344      code necessary for keeping the profiling sane.  */
5345
5346   switch (DECL_FUNCTION_CODE (fn))
5347     {
5348     case BUILT_IN_FORK:
5349       id = get_identifier ("__gcov_fork");
5350       break;
5351
5352     case BUILT_IN_EXECL:
5353       id = get_identifier ("__gcov_execl");
5354       break;
5355
5356     case BUILT_IN_EXECV:
5357       id = get_identifier ("__gcov_execv");
5358       break;
5359
5360     case BUILT_IN_EXECLP:
5361       id = get_identifier ("__gcov_execlp");
5362       break;
5363
5364     case BUILT_IN_EXECLE:
5365       id = get_identifier ("__gcov_execle");
5366       break;
5367
5368     case BUILT_IN_EXECVP:
5369       id = get_identifier ("__gcov_execvp");
5370       break;
5371
5372     case BUILT_IN_EXECVE:
5373       id = get_identifier ("__gcov_execve");
5374       break;
5375
5376     default:
5377       gcc_unreachable ();
5378     }
5379
5380   decl = build_decl (FUNCTION_DECL, id, TREE_TYPE (fn));
5381   DECL_EXTERNAL (decl) = 1;
5382   TREE_PUBLIC (decl) = 1;
5383   DECL_ARTIFICIAL (decl) = 1;
5384   TREE_NOTHROW (decl) = 1;
5385   call = build_function_call_expr (decl, arglist);
5386
5387   return expand_call (call, target, ignore);
5388 }
5389
5390 \f
5391 /* Expand the __sync_xxx_and_fetch and __sync_fetch_and_xxx intrinsics.
5392    ARGLIST is the operands list to the function.  CODE is the rtx code
5393    that corresponds to the arithmetic or logical operation from the name;
5394    an exception here is that NOT actually means NAND.  TARGET is an optional
5395    place for us to store the results; AFTER is true if this is the
5396    fetch_and_xxx form.  IGNORE is true if we don't actually care about
5397    the result of the operation at all.  */
5398
5399 static rtx
5400 expand_builtin_sync_operation (tree arglist, enum rtx_code code, bool after,
5401                                rtx target, bool ignore)
5402 {
5403   enum machine_mode mode;
5404   rtx addr, val, mem;
5405
5406   /* Expand the operands.  */
5407   addr = expand_expr (TREE_VALUE (arglist), NULL, Pmode, EXPAND_SUM);
5408   mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (TREE_VALUE (arglist))));
5409
5410   arglist = TREE_CHAIN (arglist);
5411   val = expand_expr (TREE_VALUE (arglist), NULL, mode, EXPAND_NORMAL);
5412
5413   /* Note that we explicitly do not want any alias information for this
5414      memory, so that we kill all other live memories.  Otherwise we don't
5415      satisfy the full barrier semantics of the intrinsic.  */
5416   mem = validize_mem (gen_rtx_MEM (mode, addr));
5417   MEM_VOLATILE_P (mem) = 1;
5418
5419   if (ignore)
5420     return expand_sync_operation (mem, val, code);
5421   else
5422     return expand_sync_fetch_operation (mem, val, code, after, target);
5423 }
5424
5425 /* Expand the __sync_val_compare_and_swap and __sync_bool_compare_and_swap
5426    intrinsics.  ARGLIST is the operands list to the function.  IS_BOOL is
5427    true if this is the boolean form.  TARGET is a place for us to store the
5428    results; this is NOT optional if IS_BOOL is true.  */
5429
5430 static rtx
5431 expand_builtin_compare_and_swap (tree arglist, bool is_bool, rtx target)
5432 {
5433   enum machine_mode mode;
5434   rtx addr, old_val, new_val, mem;
5435
5436   /* Expand the operands.  */
5437   addr = expand_expr (TREE_VALUE (arglist), NULL, Pmode, EXPAND_SUM);
5438   mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (TREE_VALUE (arglist))));
5439
5440   arglist = TREE_CHAIN (arglist);
5441   old_val = expand_expr (TREE_VALUE (arglist), NULL, mode, EXPAND_NORMAL);
5442
5443   arglist = TREE_CHAIN (arglist);
5444   new_val = expand_expr (TREE_VALUE (arglist), NULL, mode, EXPAND_NORMAL);
5445
5446   /* Note that we explicitly do not want any alias information for this
5447      memory, so that we kill all other live memories.  Otherwise we don't
5448      satisfy the full barrier semantics of the intrinsic.  */
5449   mem = validize_mem (gen_rtx_MEM (mode, addr));
5450   MEM_VOLATILE_P (mem) = 1;
5451
5452   if (is_bool)
5453     return expand_bool_compare_and_swap (mem, old_val, new_val, target);
5454   else
5455     return expand_val_compare_and_swap (mem, old_val, new_val, target);
5456 }
5457
5458 /* Expand the __sync_lock_test_and_set intrinsic.  Note that the most
5459    general form is actually an atomic exchange, and some targets only
5460    support a reduced form with the second argument being a constant 1.
5461    ARGLIST is the operands list to the function; TARGET is an optional
5462    place for us to store the results.  */
5463
5464 static rtx
5465 expand_builtin_lock_test_and_set (tree arglist, rtx target)
5466 {
5467   enum machine_mode mode;
5468   rtx addr, val, mem;
5469
5470   /* Expand the operands.  */
5471   addr = expand_expr (TREE_VALUE (arglist), NULL, Pmode, EXPAND_NORMAL);
5472   mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (TREE_VALUE (arglist))));
5473
5474   arglist = TREE_CHAIN (arglist);
5475   val = expand_expr (TREE_VALUE (arglist), NULL, mode, EXPAND_NORMAL);
5476
5477   /* Note that we explicitly do not want any alias information for this
5478      memory, so that we kill all other live memories.  Otherwise we don't
5479      satisfy the barrier semantics of the intrinsic.  */
5480   mem = validize_mem (gen_rtx_MEM (mode, addr));
5481   MEM_VOLATILE_P (mem) = 1;
5482
5483   return expand_sync_lock_test_and_set (mem, val, target);
5484 }
5485
5486 /* Expand the __sync_synchronize intrinsic.  */
5487
5488 static void
5489 expand_builtin_synchronize (void)
5490 {
5491   rtx body;
5492
5493 #ifdef HAVE_memory_barrier
5494   if (HAVE_memory_barrier)
5495     {
5496       emit_insn (gen_memory_barrier ());
5497       return;
5498     }
5499 #endif
5500
5501   /* If no explicit memory barrier instruction is available, create an empty
5502      asm stmt that will prevent compiler movement across the barrier.  */
5503   body = gen_rtx_ASM_INPUT (VOIDmode, "");
5504   MEM_VOLATILE_P (body) = 1;
5505   emit_insn (body);
5506 }
5507
5508 /* Expand the __sync_lock_release intrinsic.  ARGLIST is the operands list
5509    to the function.  */
5510
5511 static void
5512 expand_builtin_lock_release (tree arglist)
5513 {
5514   enum machine_mode mode;
5515   enum insn_code icode;
5516   rtx addr, val, mem, insn;
5517
5518   /* Expand the operands.  */
5519   addr = expand_expr (TREE_VALUE (arglist), NULL, Pmode, EXPAND_NORMAL);
5520   mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (TREE_VALUE (arglist))));
5521   val = const0_rtx;
5522
5523   /* Note that we explicitly do not want any alias information for this
5524      memory, so that we kill all other live memories.  Otherwise we don't
5525      satisfy the barrier semantics of the intrinsic.  */
5526   mem = validize_mem (gen_rtx_MEM (mode, addr));
5527   MEM_VOLATILE_P (mem) = 1;
5528
5529   /* If there is an explicit operation in the md file, use it.  */
5530   icode = sync_lock_release[mode];
5531   if (icode != CODE_FOR_nothing)
5532     {
5533       if (!insn_data[icode].operand[1].predicate (val, mode))
5534         val = force_reg (mode, val);
5535
5536       insn = GEN_FCN (icode) (mem, val);
5537       if (insn)
5538         {
5539           emit_insn (insn);
5540           return;
5541         }
5542     }
5543
5544   /* Otherwise we can implement this operation by emitting a barrier
5545      followed by a store of zero.  */
5546   expand_builtin_synchronize ();
5547   emit_move_insn (mem, val);
5548 }
5549 \f
5550 /* Expand an expression EXP that calls a built-in function,
5551    with result going to TARGET if that's convenient
5552    (and in mode MODE if that's convenient).
5553    SUBTARGET may be used as the target for computing one of EXP's operands.
5554    IGNORE is nonzero if the value is to be ignored.  */
5555
5556 rtx
5557 expand_builtin (tree exp, rtx target, rtx subtarget, enum machine_mode mode,
5558                 int ignore)
5559 {
5560   tree fndecl = get_callee_fndecl (exp);
5561   tree arglist = TREE_OPERAND (exp, 1);
5562   enum built_in_function fcode = DECL_FUNCTION_CODE (fndecl);
5563   enum machine_mode target_mode = TYPE_MODE (TREE_TYPE (exp));
5564
5565   if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_MD)
5566     return targetm.expand_builtin (exp, target, subtarget, mode, ignore);
5567
5568   /* When not optimizing, generate calls to library functions for a certain
5569      set of builtins.  */
5570   if (!optimize
5571       && !called_as_built_in (fndecl)
5572       && DECL_ASSEMBLER_NAME_SET_P (fndecl)
5573       && fcode != BUILT_IN_ALLOCA)
5574     return expand_call (exp, target, ignore);
5575
5576   /* The built-in function expanders test for target == const0_rtx
5577      to determine whether the function's result will be ignored.  */
5578   if (ignore)
5579     target = const0_rtx;
5580
5581   /* If the result of a pure or const built-in function is ignored, and
5582      none of its arguments are volatile, we can avoid expanding the
5583      built-in call and just evaluate the arguments for side-effects.  */
5584   if (target == const0_rtx
5585       && (DECL_IS_PURE (fndecl) || TREE_READONLY (fndecl)))
5586     {
5587       bool volatilep = false;
5588       tree arg;
5589
5590       for (arg = arglist; arg; arg = TREE_CHAIN (arg))
5591         if (TREE_THIS_VOLATILE (TREE_VALUE (arg)))
5592           {
5593             volatilep = true;
5594             break;
5595           }
5596
5597       if (! volatilep)
5598         {
5599           for (arg = arglist; arg; arg = TREE_CHAIN (arg))
5600             expand_expr (TREE_VALUE (arg), const0_rtx,
5601                          VOIDmode, EXPAND_NORMAL);
5602           return const0_rtx;
5603         }
5604     }
5605
5606   switch (fcode)
5607     {
5608     case BUILT_IN_FABS:
5609     case BUILT_IN_FABSF:
5610     case BUILT_IN_FABSL:
5611       target = expand_builtin_fabs (arglist, target, subtarget);
5612       if (target)
5613         return target;
5614       break;
5615
5616     case BUILT_IN_COPYSIGN:
5617     case BUILT_IN_COPYSIGNF:
5618     case BUILT_IN_COPYSIGNL:
5619       target = expand_builtin_copysign (arglist, target, subtarget);
5620       if (target)
5621         return target;
5622       break;
5623
5624       /* Just do a normal library call if we were unable to fold
5625          the values.  */
5626     case BUILT_IN_CABS:
5627     case BUILT_IN_CABSF:
5628     case BUILT_IN_CABSL:
5629       break;
5630
5631     case BUILT_IN_EXP:
5632     case BUILT_IN_EXPF:
5633     case BUILT_IN_EXPL:
5634     case BUILT_IN_EXP10:
5635     case BUILT_IN_EXP10F:
5636     case BUILT_IN_EXP10L:
5637     case BUILT_IN_POW10:
5638     case BUILT_IN_POW10F:
5639     case BUILT_IN_POW10L:
5640     case BUILT_IN_EXP2:
5641     case BUILT_IN_EXP2F:
5642     case BUILT_IN_EXP2L:
5643     case BUILT_IN_EXPM1:
5644     case BUILT_IN_EXPM1F:
5645     case BUILT_IN_EXPM1L:
5646     case BUILT_IN_LOGB:
5647     case BUILT_IN_LOGBF:
5648     case BUILT_IN_LOGBL:
5649     case BUILT_IN_ILOGB:
5650     case BUILT_IN_ILOGBF:
5651     case BUILT_IN_ILOGBL:
5652     case BUILT_IN_LOG:
5653     case BUILT_IN_LOGF:
5654     case BUILT_IN_LOGL:
5655     case BUILT_IN_LOG10:
5656     case BUILT_IN_LOG10F:
5657     case BUILT_IN_LOG10L:
5658     case BUILT_IN_LOG2:
5659     case BUILT_IN_LOG2F:
5660     case BUILT_IN_LOG2L:
5661     case BUILT_IN_LOG1P:
5662     case BUILT_IN_LOG1PF:
5663     case BUILT_IN_LOG1PL:
5664     case BUILT_IN_TAN:
5665     case BUILT_IN_TANF:
5666     case BUILT_IN_TANL:
5667     case BUILT_IN_ASIN:
5668     case BUILT_IN_ASINF:
5669     case BUILT_IN_ASINL:
5670     case BUILT_IN_ACOS:
5671     case BUILT_IN_ACOSF:
5672     case BUILT_IN_ACOSL:
5673     case BUILT_IN_ATAN:
5674     case BUILT_IN_ATANF:
5675     case BUILT_IN_ATANL:
5676       /* Treat these like sqrt only if unsafe math optimizations are allowed,
5677          because of possible accuracy problems.  */
5678       if (! flag_unsafe_math_optimizations)
5679         break;
5680     case BUILT_IN_SQRT:
5681     case BUILT_IN_SQRTF:
5682     case BUILT_IN_SQRTL:
5683     case BUILT_IN_FLOOR:
5684     case BUILT_IN_FLOORF:
5685     case BUILT_IN_FLOORL:
5686     case BUILT_IN_CEIL:
5687     case BUILT_IN_CEILF:
5688     case BUILT_IN_CEILL:
5689     case BUILT_IN_TRUNC:
5690     case BUILT_IN_TRUNCF:
5691     case BUILT_IN_TRUNCL:
5692     case BUILT_IN_ROUND:
5693     case BUILT_IN_ROUNDF:
5694     case BUILT_IN_ROUNDL:
5695     case BUILT_IN_NEARBYINT:
5696     case BUILT_IN_NEARBYINTF:
5697     case BUILT_IN_NEARBYINTL:
5698     case BUILT_IN_RINT:
5699     case BUILT_IN_RINTF:
5700     case BUILT_IN_RINTL:
5701     case BUILT_IN_LRINT:
5702     case BUILT_IN_LRINTF:
5703     case BUILT_IN_LRINTL:
5704     case BUILT_IN_LLRINT:
5705     case BUILT_IN_LLRINTF:
5706     case BUILT_IN_LLRINTL:
5707       target = expand_builtin_mathfn (exp, target, subtarget);
5708       if (target)
5709         return target;
5710       break;
5711
5712     case BUILT_IN_LCEIL:
5713     case BUILT_IN_LCEILF:
5714     case BUILT_IN_LCEILL:
5715     case BUILT_IN_LLCEIL:
5716     case BUILT_IN_LLCEILF:
5717     case BUILT_IN_LLCEILL:
5718     case BUILT_IN_LFLOOR:
5719     case BUILT_IN_LFLOORF:
5720     case BUILT_IN_LFLOORL:
5721     case BUILT_IN_LLFLOOR:
5722     case BUILT_IN_LLFLOORF:
5723     case BUILT_IN_LLFLOORL:
5724       target = expand_builtin_int_roundingfn (exp, target, subtarget);
5725       if (target)
5726         return target;
5727       break;
5728
5729     case BUILT_IN_POW:
5730     case BUILT_IN_POWF:
5731     case BUILT_IN_POWL:
5732       target = expand_builtin_pow (exp, target, subtarget);
5733       if (target)
5734         return target;
5735       break;
5736
5737     case BUILT_IN_POWI:
5738     case BUILT_IN_POWIF:
5739     case BUILT_IN_POWIL:
5740       target = expand_builtin_powi (exp, target, subtarget);
5741       if (target)
5742         return target;
5743       break;
5744
5745     case BUILT_IN_ATAN2:
5746     case BUILT_IN_ATAN2F:
5747     case BUILT_IN_ATAN2L:
5748     case BUILT_IN_LDEXP:
5749     case BUILT_IN_LDEXPF:
5750     case BUILT_IN_LDEXPL:
5751     case BUILT_IN_FMOD:
5752     case BUILT_IN_FMODF:
5753     case BUILT_IN_FMODL:
5754     case BUILT_IN_DREM:
5755     case BUILT_IN_DREMF:
5756     case BUILT_IN_DREML:
5757       if (! flag_unsafe_math_optimizations)
5758         break;
5759       target = expand_builtin_mathfn_2 (exp, target, subtarget);
5760       if (target)
5761         return target;
5762       break;
5763
5764     case BUILT_IN_SIN:
5765     case BUILT_IN_SINF:
5766     case BUILT_IN_SINL:
5767     case BUILT_IN_COS:
5768     case BUILT_IN_COSF:
5769     case BUILT_IN_COSL:
5770       if (! flag_unsafe_math_optimizations)
5771         break;
5772       target = expand_builtin_mathfn_3 (exp, target, subtarget);
5773       if (target)
5774         return target;
5775       break;
5776
5777     case BUILT_IN_APPLY_ARGS:
5778       return expand_builtin_apply_args ();
5779
5780       /* __builtin_apply (FUNCTION, ARGUMENTS, ARGSIZE) invokes
5781          FUNCTION with a copy of the parameters described by
5782          ARGUMENTS, and ARGSIZE.  It returns a block of memory
5783          allocated on the stack into which is stored all the registers
5784          that might possibly be used for returning the result of a
5785          function.  ARGUMENTS is the value returned by
5786          __builtin_apply_args.  ARGSIZE is the number of bytes of
5787          arguments that must be copied.  ??? How should this value be
5788          computed?  We'll also need a safe worst case value for varargs
5789          functions.  */
5790     case BUILT_IN_APPLY:
5791       if (!validate_arglist (arglist, POINTER_TYPE,
5792                              POINTER_TYPE, INTEGER_TYPE, VOID_TYPE)
5793           && !validate_arglist (arglist, REFERENCE_TYPE,
5794                                 POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
5795         return const0_rtx;
5796       else
5797         {
5798           int i;
5799           tree t;
5800           rtx ops[3];
5801
5802           for (t = arglist, i = 0; t; t = TREE_CHAIN (t), i++)
5803             ops[i] = expand_expr (TREE_VALUE (t), NULL_RTX, VOIDmode, 0);
5804
5805           return expand_builtin_apply (ops[0], ops[1], ops[2]);
5806         }
5807
5808       /* __builtin_return (RESULT) causes the function to return the
5809          value described by RESULT.  RESULT is address of the block of
5810          memory returned by __builtin_apply.  */
5811     case BUILT_IN_RETURN:
5812       if (validate_arglist (arglist, POINTER_TYPE, VOID_TYPE))
5813         expand_builtin_return (expand_expr (TREE_VALUE (arglist),
5814                                             NULL_RTX, VOIDmode, 0));
5815       return const0_rtx;
5816
5817     case BUILT_IN_SAVEREGS:
5818       return expand_builtin_saveregs ();
5819
5820     case BUILT_IN_ARGS_INFO:
5821       return expand_builtin_args_info (arglist);
5822
5823       /* Return the address of the first anonymous stack arg.  */
5824     case BUILT_IN_NEXT_ARG:
5825       if (fold_builtin_next_arg (arglist))
5826         return const0_rtx;
5827       return expand_builtin_next_arg ();
5828
5829     case BUILT_IN_CLASSIFY_TYPE:
5830       return expand_builtin_classify_type (arglist);
5831
5832     case BUILT_IN_CONSTANT_P:
5833       return const0_rtx;
5834
5835     case BUILT_IN_FRAME_ADDRESS:
5836     case BUILT_IN_RETURN_ADDRESS:
5837       return expand_builtin_frame_address (fndecl, arglist);
5838
5839     /* Returns the address of the area where the structure is returned.
5840        0 otherwise.  */
5841     case BUILT_IN_AGGREGATE_INCOMING_ADDRESS:
5842       if (arglist != 0
5843           || ! AGGREGATE_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl)))
5844           || !MEM_P (DECL_RTL (DECL_RESULT (current_function_decl))))
5845         return const0_rtx;
5846       else
5847         return XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
5848
5849     case BUILT_IN_ALLOCA:
5850       target = expand_builtin_alloca (arglist, target);
5851       if (target)
5852         return target;
5853       break;
5854
5855     case BUILT_IN_STACK_SAVE:
5856       return expand_stack_save ();
5857
5858     case BUILT_IN_STACK_RESTORE:
5859       expand_stack_restore (TREE_VALUE (arglist));
5860       return const0_rtx;
5861
5862     case BUILT_IN_FFS:
5863     case BUILT_IN_FFSL:
5864     case BUILT_IN_FFSLL:
5865     case BUILT_IN_FFSIMAX:
5866       target = expand_builtin_unop (target_mode, arglist, target,
5867                                     subtarget, ffs_optab);
5868       if (target)
5869         return target;
5870       break;
5871
5872     case BUILT_IN_CLZ:
5873     case BUILT_IN_CLZL:
5874     case BUILT_IN_CLZLL:
5875     case BUILT_IN_CLZIMAX:
5876       target = expand_builtin_unop (target_mode, arglist, target,
5877                                     subtarget, clz_optab);
5878       if (target)
5879         return target;
5880       break;
5881
5882     case BUILT_IN_CTZ:
5883     case BUILT_IN_CTZL:
5884     case BUILT_IN_CTZLL:
5885     case BUILT_IN_CTZIMAX:
5886       target = expand_builtin_unop (target_mode, arglist, target,
5887                                     subtarget, ctz_optab);
5888       if (target)
5889         return target;
5890       break;
5891
5892     case BUILT_IN_POPCOUNT:
5893     case BUILT_IN_POPCOUNTL:
5894     case BUILT_IN_POPCOUNTLL:
5895     case BUILT_IN_POPCOUNTIMAX:
5896       target = expand_builtin_unop (target_mode, arglist, target,
5897                                     subtarget, popcount_optab);
5898       if (target)
5899         return target;
5900       break;
5901
5902     case BUILT_IN_PARITY:
5903     case BUILT_IN_PARITYL:
5904     case BUILT_IN_PARITYLL:
5905     case BUILT_IN_PARITYIMAX:
5906       target = expand_builtin_unop (target_mode, arglist, target,
5907                                     subtarget, parity_optab);
5908       if (target)
5909         return target;
5910       break;
5911
5912     case BUILT_IN_STRLEN:
5913       target = expand_builtin_strlen (arglist, target, target_mode);
5914       if (target)
5915         return target;
5916       break;
5917
5918     case BUILT_IN_STRCPY:
5919       target = expand_builtin_strcpy (fndecl, arglist, target, mode);
5920       if (target)
5921         return target;
5922       break;
5923
5924     case BUILT_IN_STRNCPY:
5925       target = expand_builtin_strncpy (exp, target, mode);
5926       if (target)
5927         return target;
5928       break;
5929
5930     case BUILT_IN_STPCPY:
5931       target = expand_builtin_stpcpy (exp, target, mode);
5932       if (target)
5933         return target;
5934       break;
5935
5936     case BUILT_IN_STRCAT:
5937       target = expand_builtin_strcat (fndecl, arglist, target, mode);
5938       if (target)
5939         return target;
5940       break;
5941
5942     case BUILT_IN_STRNCAT:
5943       target = expand_builtin_strncat (arglist, target, mode);
5944       if (target)
5945         return target;
5946       break;
5947
5948     case BUILT_IN_STRSPN:
5949       target = expand_builtin_strspn (arglist, target, mode);
5950       if (target)
5951         return target;
5952       break;
5953
5954     case BUILT_IN_STRCSPN:
5955       target = expand_builtin_strcspn (arglist, target, mode);
5956       if (target)
5957         return target;
5958       break;
5959
5960     case BUILT_IN_STRSTR:
5961       target = expand_builtin_strstr (arglist, TREE_TYPE (exp), target, mode);
5962       if (target)
5963         return target;
5964       break;
5965
5966     case BUILT_IN_STRPBRK:
5967       target = expand_builtin_strpbrk (arglist, TREE_TYPE (exp), target, mode);
5968       if (target)
5969         return target;
5970       break;
5971
5972     case BUILT_IN_INDEX:
5973     case BUILT_IN_STRCHR:
5974       target = expand_builtin_strchr (arglist, TREE_TYPE (exp), target, mode);
5975       if (target)
5976         return target;
5977       break;
5978
5979     case BUILT_IN_RINDEX:
5980     case BUILT_IN_STRRCHR:
5981       target = expand_builtin_strrchr (arglist, TREE_TYPE (exp), target, mode);
5982       if (target)
5983         return target;
5984       break;
5985
5986     case BUILT_IN_MEMCPY:
5987       target = expand_builtin_memcpy (exp, target, mode);
5988       if (target)
5989         return target;
5990       break;
5991
5992     case BUILT_IN_MEMPCPY:
5993       target = expand_builtin_mempcpy (arglist, TREE_TYPE (exp), target, mode, /*endp=*/ 1);
5994       if (target)
5995         return target;
5996       break;
5997
5998     case BUILT_IN_MEMMOVE:
5999       target = expand_builtin_memmove (arglist, TREE_TYPE (exp), target,
6000                                        mode, exp);
6001       if (target)
6002         return target;
6003       break;
6004
6005     case BUILT_IN_BCOPY:
6006       target = expand_builtin_bcopy (exp);
6007       if (target)
6008         return target;
6009       break;
6010
6011     case BUILT_IN_MEMSET:
6012       target = expand_builtin_memset (arglist, target, mode, exp);
6013       if (target)
6014         return target;
6015       break;
6016
6017     case BUILT_IN_BZERO:
6018       target = expand_builtin_bzero (exp);
6019       if (target)
6020         return target;
6021       break;
6022
6023     case BUILT_IN_STRCMP:
6024       target = expand_builtin_strcmp (exp, target, mode);
6025       if (target)
6026         return target;
6027       break;
6028
6029     case BUILT_IN_STRNCMP:
6030       target = expand_builtin_strncmp (exp, target, mode);
6031       if (target)
6032         return target;
6033       break;
6034
6035     case BUILT_IN_BCMP:
6036     case BUILT_IN_MEMCMP:
6037       target = expand_builtin_memcmp (exp, arglist, target, mode);
6038       if (target)
6039         return target;
6040       break;
6041
6042     case BUILT_IN_SETJMP:
6043       target = expand_builtin_setjmp (arglist, target);
6044       if (target)
6045         return target;
6046       break;
6047
6048       /* __builtin_longjmp is passed a pointer to an array of five words.
6049          It's similar to the C library longjmp function but works with
6050          __builtin_setjmp above.  */
6051     case BUILT_IN_LONGJMP:
6052       if (!validate_arglist (arglist, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
6053         break;
6054       else
6055         {
6056           rtx buf_addr = expand_expr (TREE_VALUE (arglist), subtarget,
6057                                       VOIDmode, 0);
6058           rtx value = expand_expr (TREE_VALUE (TREE_CHAIN (arglist)),
6059                                    NULL_RTX, VOIDmode, 0);
6060
6061           if (value != const1_rtx)
6062             {
6063               error ("%<__builtin_longjmp%> second argument must be 1");
6064               return const0_rtx;
6065             }
6066
6067           expand_builtin_longjmp (buf_addr, value);
6068           return const0_rtx;
6069         }
6070
6071     case BUILT_IN_NONLOCAL_GOTO:
6072       target = expand_builtin_nonlocal_goto (arglist);
6073       if (target)
6074         return target;
6075       break;
6076
6077       /* This updates the setjmp buffer that is its argument with the value
6078          of the current stack pointer.  */
6079     case BUILT_IN_UPDATE_SETJMP_BUF:
6080       if (validate_arglist (arglist, POINTER_TYPE, VOID_TYPE))
6081         {
6082           rtx buf_addr
6083             = expand_expr (TREE_VALUE (arglist), NULL_RTX, VOIDmode, 0);
6084
6085           expand_builtin_update_setjmp_buf (buf_addr);
6086           return const0_rtx;
6087         }
6088       break;
6089
6090     case BUILT_IN_TRAP:
6091       expand_builtin_trap ();
6092       return const0_rtx;
6093
6094     case BUILT_IN_PRINTF:
6095       target = expand_builtin_printf (exp, target, mode, false);
6096       if (target)
6097         return target;
6098       break;
6099
6100     case BUILT_IN_PRINTF_UNLOCKED:
6101       target = expand_builtin_printf (exp, target, mode, true);
6102       if (target)
6103         return target;
6104       break;
6105
6106     case BUILT_IN_FPUTS:
6107       target = expand_builtin_fputs (arglist, target, false);
6108       if (target)
6109         return target;
6110       break;
6111     case BUILT_IN_FPUTS_UNLOCKED:
6112       target = expand_builtin_fputs (arglist, target, true);
6113       if (target)
6114         return target;
6115       break;
6116
6117     case BUILT_IN_FPRINTF:
6118       target = expand_builtin_fprintf (exp, target, mode, false);
6119       if (target)
6120         return target;
6121       break;
6122
6123     case BUILT_IN_FPRINTF_UNLOCKED:
6124       target = expand_builtin_fprintf (exp, target, mode, true);
6125       if (target)
6126         return target;
6127       break;
6128
6129     case BUILT_IN_SPRINTF:
6130       target = expand_builtin_sprintf (arglist, target, mode);
6131       if (target)
6132         return target;
6133       break;
6134
6135     case BUILT_IN_SIGNBIT:
6136     case BUILT_IN_SIGNBITF:
6137     case BUILT_IN_SIGNBITL:
6138       target = expand_builtin_signbit (exp, target);
6139       if (target)
6140         return target;
6141       break;
6142
6143       /* Various hooks for the DWARF 2 __throw routine.  */
6144     case BUILT_IN_UNWIND_INIT:
6145       expand_builtin_unwind_init ();
6146       return const0_rtx;
6147     case BUILT_IN_DWARF_CFA:
6148       return virtual_cfa_rtx;
6149 #ifdef DWARF2_UNWIND_INFO
6150     case BUILT_IN_DWARF_SP_COLUMN:
6151       return expand_builtin_dwarf_sp_column ();
6152     case BUILT_IN_INIT_DWARF_REG_SIZES:
6153       expand_builtin_init_dwarf_reg_sizes (TREE_VALUE (arglist));
6154       return const0_rtx;
6155 #endif
6156     case BUILT_IN_FROB_RETURN_ADDR:
6157       return expand_builtin_frob_return_addr (TREE_VALUE (arglist));
6158     case BUILT_IN_EXTRACT_RETURN_ADDR:
6159       return expand_builtin_extract_return_addr (TREE_VALUE (arglist));
6160     case BUILT_IN_EH_RETURN:
6161       expand_builtin_eh_return (TREE_VALUE (arglist),
6162                                 TREE_VALUE (TREE_CHAIN (arglist)));
6163       return const0_rtx;
6164 #ifdef EH_RETURN_DATA_REGNO
6165     case BUILT_IN_EH_RETURN_DATA_REGNO:
6166       return expand_builtin_eh_return_data_regno (arglist);
6167 #endif
6168     case BUILT_IN_EXTEND_POINTER:
6169       return expand_builtin_extend_pointer (TREE_VALUE (arglist));
6170
6171     case BUILT_IN_VA_START:
6172     case BUILT_IN_STDARG_START:
6173       return expand_builtin_va_start (arglist);
6174     case BUILT_IN_VA_END:
6175       return expand_builtin_va_end (arglist);
6176     case BUILT_IN_VA_COPY:
6177       return expand_builtin_va_copy (arglist);
6178     case BUILT_IN_EXPECT:
6179       return expand_builtin_expect (arglist, target);
6180     case BUILT_IN_PREFETCH:
6181       expand_builtin_prefetch (arglist);
6182       return const0_rtx;
6183
6184     case BUILT_IN_PROFILE_FUNC_ENTER:
6185       return expand_builtin_profile_func (false);
6186     case BUILT_IN_PROFILE_FUNC_EXIT:
6187       return expand_builtin_profile_func (true);
6188
6189     case BUILT_IN_INIT_TRAMPOLINE:
6190       return expand_builtin_init_trampoline (arglist);
6191     case BUILT_IN_ADJUST_TRAMPOLINE:
6192       return expand_builtin_adjust_trampoline (arglist);
6193
6194     case BUILT_IN_FORK:
6195     case BUILT_IN_EXECL:
6196     case BUILT_IN_EXECV:
6197     case BUILT_IN_EXECLP:
6198     case BUILT_IN_EXECLE:
6199     case BUILT_IN_EXECVP:
6200     case BUILT_IN_EXECVE:
6201       target = expand_builtin_fork_or_exec (fndecl, arglist, target, ignore);
6202       if (target)
6203         return target;
6204       break;
6205
6206     case BUILT_IN_FETCH_AND_ADD_1:
6207     case BUILT_IN_FETCH_AND_ADD_2:
6208     case BUILT_IN_FETCH_AND_ADD_4:
6209     case BUILT_IN_FETCH_AND_ADD_8:
6210       target = expand_builtin_sync_operation (arglist, PLUS,
6211                                               false, target, ignore);
6212       if (target)
6213         return target;
6214       break;
6215
6216     case BUILT_IN_FETCH_AND_SUB_1:
6217     case BUILT_IN_FETCH_AND_SUB_2:
6218     case BUILT_IN_FETCH_AND_SUB_4:
6219     case BUILT_IN_FETCH_AND_SUB_8:
6220       target = expand_builtin_sync_operation (arglist, MINUS,
6221                                               false, target, ignore);
6222       if (target)
6223         return target;
6224       break;
6225
6226     case BUILT_IN_FETCH_AND_OR_1:
6227     case BUILT_IN_FETCH_AND_OR_2:
6228     case BUILT_IN_FETCH_AND_OR_4:
6229     case BUILT_IN_FETCH_AND_OR_8:
6230       target = expand_builtin_sync_operation (arglist, IOR,
6231                                               false, target, ignore);
6232       if (target)
6233         return target;
6234       break;
6235
6236     case BUILT_IN_FETCH_AND_AND_1:
6237     case BUILT_IN_FETCH_AND_AND_2:
6238     case BUILT_IN_FETCH_AND_AND_4:
6239     case BUILT_IN_FETCH_AND_AND_8:
6240       target = expand_builtin_sync_operation (arglist, AND,
6241                                               false, target, ignore);
6242       if (target)
6243         return target;
6244       break;
6245
6246     case BUILT_IN_FETCH_AND_XOR_1:
6247     case BUILT_IN_FETCH_AND_XOR_2:
6248     case BUILT_IN_FETCH_AND_XOR_4:
6249     case BUILT_IN_FETCH_AND_XOR_8:
6250       target = expand_builtin_sync_operation (arglist, XOR,
6251                                               false, target, ignore);
6252       if (target)
6253         return target;
6254       break;
6255
6256     case BUILT_IN_FETCH_AND_NAND_1:
6257     case BUILT_IN_FETCH_AND_NAND_2:
6258     case BUILT_IN_FETCH_AND_NAND_4:
6259     case BUILT_IN_FETCH_AND_NAND_8:
6260       target = expand_builtin_sync_operation (arglist, NOT,
6261                                               false, target, ignore);
6262       if (target)
6263         return target;
6264       break;
6265
6266     case BUILT_IN_ADD_AND_FETCH_1:
6267     case BUILT_IN_ADD_AND_FETCH_2:
6268     case BUILT_IN_ADD_AND_FETCH_4:
6269     case BUILT_IN_ADD_AND_FETCH_8:
6270       target = expand_builtin_sync_operation (arglist, PLUS,
6271                                               true, target, ignore);
6272       if (target)
6273         return target;
6274       break;
6275
6276     case BUILT_IN_SUB_AND_FETCH_1:
6277     case BUILT_IN_SUB_AND_FETCH_2:
6278     case BUILT_IN_SUB_AND_FETCH_4:
6279     case BUILT_IN_SUB_AND_FETCH_8:
6280       target = expand_builtin_sync_operation (arglist, MINUS,
6281                                               true, target, ignore);
6282       if (target)
6283         return target;
6284       break;
6285
6286     case BUILT_IN_OR_AND_FETCH_1:
6287     case BUILT_IN_OR_AND_FETCH_2:
6288     case BUILT_IN_OR_AND_FETCH_4:
6289     case BUILT_IN_OR_AND_FETCH_8:
6290       target = expand_builtin_sync_operation (arglist, IOR,
6291                                               true, target, ignore);
6292       if (target)
6293         return target;
6294       break;
6295
6296     case BUILT_IN_AND_AND_FETCH_1:
6297     case BUILT_IN_AND_AND_FETCH_2:
6298     case BUILT_IN_AND_AND_FETCH_4:
6299     case BUILT_IN_AND_AND_FETCH_8:
6300       target = expand_builtin_sync_operation (arglist, AND,
6301                                               true, target, ignore);
6302       if (target)
6303         return target;
6304       break;
6305
6306     case BUILT_IN_XOR_AND_FETCH_1:
6307     case BUILT_IN_XOR_AND_FETCH_2:
6308     case BUILT_IN_XOR_AND_FETCH_4:
6309     case BUILT_IN_XOR_AND_FETCH_8:
6310       target = expand_builtin_sync_operation (arglist, XOR,
6311                                               true, target, ignore);
6312       if (target)
6313         return target;
6314       break;
6315
6316     case BUILT_IN_NAND_AND_FETCH_1:
6317     case BUILT_IN_NAND_AND_FETCH_2:
6318     case BUILT_IN_NAND_AND_FETCH_4:
6319     case BUILT_IN_NAND_AND_FETCH_8:
6320       target = expand_builtin_sync_operation (arglist, NOT,
6321                                               true, target, ignore);
6322       if (target)
6323         return target;
6324       break;
6325
6326     case BUILT_IN_BOOL_COMPARE_AND_SWAP_1:
6327     case BUILT_IN_BOOL_COMPARE_AND_SWAP_2:
6328     case BUILT_IN_BOOL_COMPARE_AND_SWAP_4:
6329     case BUILT_IN_BOOL_COMPARE_AND_SWAP_8:
6330       if (mode == VOIDmode)
6331         mode = TYPE_MODE (boolean_type_node);
6332       if (!target || !register_operand (target, mode))
6333         target = gen_reg_rtx (mode);
6334       target = expand_builtin_compare_and_swap (arglist, true, target);
6335       if (target)
6336         return target;
6337       break;
6338
6339     case BUILT_IN_VAL_COMPARE_AND_SWAP_1:
6340     case BUILT_IN_VAL_COMPARE_AND_SWAP_2:
6341     case BUILT_IN_VAL_COMPARE_AND_SWAP_4:
6342     case BUILT_IN_VAL_COMPARE_AND_SWAP_8:
6343       target = expand_builtin_compare_and_swap (arglist, false, target);
6344       if (target)
6345         return target;
6346       break;
6347
6348     case BUILT_IN_LOCK_TEST_AND_SET_1:
6349     case BUILT_IN_LOCK_TEST_AND_SET_2:
6350     case BUILT_IN_LOCK_TEST_AND_SET_4:
6351     case BUILT_IN_LOCK_TEST_AND_SET_8:
6352       target = expand_builtin_lock_test_and_set (arglist, target);
6353       if (target)
6354         return target;
6355       break;
6356
6357     case BUILT_IN_LOCK_RELEASE_1:
6358     case BUILT_IN_LOCK_RELEASE_2:
6359     case BUILT_IN_LOCK_RELEASE_4:
6360     case BUILT_IN_LOCK_RELEASE_8:
6361       expand_builtin_lock_release (arglist);
6362       return const0_rtx;
6363
6364     case BUILT_IN_SYNCHRONIZE:
6365       expand_builtin_synchronize ();
6366       return const0_rtx;
6367
6368     case BUILT_IN_OBJECT_SIZE:
6369       return expand_builtin_object_size (exp);
6370
6371     case BUILT_IN_MEMCPY_CHK:
6372     case BUILT_IN_MEMPCPY_CHK:
6373     case BUILT_IN_MEMMOVE_CHK:
6374     case BUILT_IN_MEMSET_CHK:
6375       target = expand_builtin_memory_chk (exp, target, mode, fcode);
6376       if (target)
6377         return target;
6378       break;
6379
6380     case BUILT_IN_STRCPY_CHK:
6381     case BUILT_IN_STPCPY_CHK:
6382     case BUILT_IN_STRNCPY_CHK:
6383     case BUILT_IN_STRCAT_CHK:
6384     case BUILT_IN_SNPRINTF_CHK:
6385     case BUILT_IN_VSNPRINTF_CHK:
6386       maybe_emit_chk_warning (exp, fcode);
6387       break;
6388
6389     case BUILT_IN_SPRINTF_CHK:
6390     case BUILT_IN_VSPRINTF_CHK:
6391       maybe_emit_sprintf_chk_warning (exp, fcode);
6392       break;
6393
6394     default:    /* just do library call, if unknown builtin */
6395       break;
6396     }
6397
6398   /* The switch statement above can drop through to cause the function
6399      to be called normally.  */
6400   return expand_call (exp, target, ignore);
6401 }
6402
6403 /* Determine whether a tree node represents a call to a built-in
6404    function.  If the tree T is a call to a built-in function with
6405    the right number of arguments of the appropriate types, return
6406    the DECL_FUNCTION_CODE of the call, e.g. BUILT_IN_SQRT.
6407    Otherwise the return value is END_BUILTINS.  */
6408
6409 enum built_in_function
6410 builtin_mathfn_code (tree t)
6411 {
6412   tree fndecl, arglist, parmlist;
6413   tree argtype, parmtype;
6414
6415   if (TREE_CODE (t) != CALL_EXPR
6416       || TREE_CODE (TREE_OPERAND (t, 0)) != ADDR_EXPR)
6417     return END_BUILTINS;
6418
6419   fndecl = get_callee_fndecl (t);
6420   if (fndecl == NULL_TREE
6421       || TREE_CODE (fndecl) != FUNCTION_DECL
6422       || ! DECL_BUILT_IN (fndecl)
6423       || DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_MD)
6424     return END_BUILTINS;
6425
6426   arglist = TREE_OPERAND (t, 1);
6427   parmlist = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
6428   for (; parmlist; parmlist = TREE_CHAIN (parmlist))
6429     {
6430       /* If a function doesn't take a variable number of arguments,
6431          the last element in the list will have type `void'.  */
6432       parmtype = TREE_VALUE (parmlist);
6433       if (VOID_TYPE_P (parmtype))
6434         {
6435           if (arglist)
6436             return END_BUILTINS;
6437           return DECL_FUNCTION_CODE (fndecl);
6438         }
6439
6440       if (! arglist)
6441         return END_BUILTINS;
6442
6443       argtype = TREE_TYPE (TREE_VALUE (arglist));
6444
6445       if (SCALAR_FLOAT_TYPE_P (parmtype))
6446         {
6447           if (! SCALAR_FLOAT_TYPE_P (argtype))
6448             return END_BUILTINS;
6449         }
6450       else if (COMPLEX_FLOAT_TYPE_P (parmtype))
6451         {
6452           if (! COMPLEX_FLOAT_TYPE_P (argtype))
6453             return END_BUILTINS;
6454         }
6455       else if (POINTER_TYPE_P (parmtype))
6456         {
6457           if (! POINTER_TYPE_P (argtype))
6458             return END_BUILTINS;
6459         }
6460       else if (INTEGRAL_TYPE_P (parmtype))
6461         {
6462           if (! INTEGRAL_TYPE_P (argtype))
6463             return END_BUILTINS;
6464         }
6465       else
6466         return END_BUILTINS;
6467
6468       arglist = TREE_CHAIN (arglist);
6469     }
6470
6471   /* Variable-length argument list.  */
6472   return DECL_FUNCTION_CODE (fndecl);
6473 }
6474
6475 /* Fold a call to __builtin_constant_p, if we know it will evaluate to a
6476    constant.  ARGLIST is the argument list of the call.  */
6477
6478 static tree
6479 fold_builtin_constant_p (tree arglist)
6480 {
6481   if (arglist == 0)
6482     return 0;
6483
6484   arglist = TREE_VALUE (arglist);
6485
6486   /* We return 1 for a numeric type that's known to be a constant
6487      value at compile-time or for an aggregate type that's a
6488      literal constant.  */
6489   STRIP_NOPS (arglist);
6490
6491   /* If we know this is a constant, emit the constant of one.  */
6492   if (CONSTANT_CLASS_P (arglist)
6493       || (TREE_CODE (arglist) == CONSTRUCTOR
6494           && TREE_CONSTANT (arglist)))
6495     return integer_one_node;
6496   if (TREE_CODE (arglist) == ADDR_EXPR)
6497     {
6498        tree op = TREE_OPERAND (arglist, 0);
6499        if (TREE_CODE (op) == STRING_CST
6500            || (TREE_CODE (op) == ARRAY_REF
6501                && integer_zerop (TREE_OPERAND (op, 1))
6502                && TREE_CODE (TREE_OPERAND (op, 0)) == STRING_CST))
6503          return integer_one_node;
6504     }
6505
6506   /* If this expression has side effects, show we don't know it to be a
6507      constant.  Likewise if it's a pointer or aggregate type since in
6508      those case we only want literals, since those are only optimized
6509      when generating RTL, not later.
6510      And finally, if we are compiling an initializer, not code, we
6511      need to return a definite result now; there's not going to be any
6512      more optimization done.  */
6513   if (TREE_SIDE_EFFECTS (arglist)
6514       || AGGREGATE_TYPE_P (TREE_TYPE (arglist))
6515       || POINTER_TYPE_P (TREE_TYPE (arglist))
6516       || cfun == 0)
6517     return integer_zero_node;
6518
6519   return 0;
6520 }
6521
6522 /* Fold a call to __builtin_expect, if we expect that a comparison against
6523    the argument will fold to a constant.  In practice, this means a true
6524    constant or the address of a non-weak symbol.  ARGLIST is the argument
6525    list of the call.  */
6526
6527 static tree
6528 fold_builtin_expect (tree arglist)
6529 {
6530   tree arg, inner;
6531
6532   if (arglist == 0)
6533     return 0;
6534
6535   arg = TREE_VALUE (arglist);
6536
6537   /* If the argument isn't invariant, then there's nothing we can do.  */
6538   if (!TREE_INVARIANT (arg))
6539     return 0;
6540
6541   /* If we're looking at an address of a weak decl, then do not fold.  */
6542   inner = arg;
6543   STRIP_NOPS (inner);
6544   if (TREE_CODE (inner) == ADDR_EXPR)
6545     {
6546       do
6547         {
6548           inner = TREE_OPERAND (inner, 0);
6549         }
6550       while (TREE_CODE (inner) == COMPONENT_REF
6551              || TREE_CODE (inner) == ARRAY_REF);
6552       if (DECL_P (inner) && DECL_WEAK (inner))
6553         return 0;
6554     }
6555
6556   /* Otherwise, ARG already has the proper type for the return value.  */
6557   return arg;
6558 }
6559
6560 /* Fold a call to __builtin_classify_type.  */
6561
6562 static tree
6563 fold_builtin_classify_type (tree arglist)
6564 {
6565   if (arglist == 0)
6566     return build_int_cst (NULL_TREE, no_type_class);
6567
6568   return build_int_cst (NULL_TREE,
6569                         type_to_class (TREE_TYPE (TREE_VALUE (arglist))));
6570 }
6571
6572 /* Fold a call to __builtin_strlen.  */
6573
6574 static tree
6575 fold_builtin_strlen (tree arglist)
6576 {
6577   if (!validate_arglist (arglist, POINTER_TYPE, VOID_TYPE))
6578     return NULL_TREE;
6579   else
6580     {
6581       tree len = c_strlen (TREE_VALUE (arglist), 0);
6582
6583       if (len)
6584         {
6585           /* Convert from the internal "sizetype" type to "size_t".  */
6586           if (size_type_node)
6587             len = fold_convert (size_type_node, len);
6588           return len;
6589         }
6590
6591       return NULL_TREE;
6592     }
6593 }
6594
6595 /* Fold a call to __builtin_inf or __builtin_huge_val.  */
6596
6597 static tree
6598 fold_builtin_inf (tree type, int warn)
6599 {
6600   REAL_VALUE_TYPE real;
6601
6602   /* __builtin_inff is intended to be usable to define INFINITY on all
6603      targets.  If an infinity is not available, INFINITY expands "to a
6604      positive constant of type float that overflows at translation
6605      time", footnote "In this case, using INFINITY will violate the
6606      constraint in 6.4.4 and thus require a diagnostic." (C99 7.12#4).
6607      Thus we pedwarn to ensure this constraint violation is
6608      diagnosed.  */
6609   if (!MODE_HAS_INFINITIES (TYPE_MODE (type)) && warn)
6610     pedwarn ("target format does not support infinity");
6611
6612   real_inf (&real);
6613   return build_real (type, real);
6614 }
6615
6616 /* Fold a call to __builtin_nan or __builtin_nans.  */
6617
6618 static tree
6619 fold_builtin_nan (tree arglist, tree type, int quiet)
6620 {
6621   REAL_VALUE_TYPE real;
6622   const char *str;
6623
6624   if (!validate_arglist (arglist, POINTER_TYPE, VOID_TYPE))
6625     return 0;
6626   str = c_getstr (TREE_VALUE (arglist));
6627   if (!str)
6628     return 0;
6629
6630   if (!real_nan (&real, str, quiet, TYPE_MODE (type)))
6631     return 0;
6632
6633   return build_real (type, real);
6634 }
6635
6636 /* Return true if the floating point expression T has an integer value.
6637    We also allow +Inf, -Inf and NaN to be considered integer values.  */
6638
6639 static bool
6640 integer_valued_real_p (tree t)
6641 {
6642   switch (TREE_CODE (t))
6643     {
6644     case FLOAT_EXPR:
6645       return true;
6646
6647     case ABS_EXPR:
6648     case SAVE_EXPR:
6649     case NON_LVALUE_EXPR:
6650       return integer_valued_real_p (TREE_OPERAND (t, 0));
6651
6652     case COMPOUND_EXPR:
6653     case MODIFY_EXPR:
6654     case BIND_EXPR:
6655       return integer_valued_real_p (TREE_OPERAND (t, 1));
6656
6657     case PLUS_EXPR:
6658     case MINUS_EXPR:
6659     case MULT_EXPR:
6660     case MIN_EXPR:
6661     case MAX_EXPR:
6662       return integer_valued_real_p (TREE_OPERAND (t, 0))
6663              && integer_valued_real_p (TREE_OPERAND (t, 1));
6664
6665     case COND_EXPR:
6666       return integer_valued_real_p (TREE_OPERAND (t, 1))
6667              && integer_valued_real_p (TREE_OPERAND (t, 2));
6668
6669     case REAL_CST:
6670       if (! TREE_CONSTANT_OVERFLOW (t))
6671       {
6672         REAL_VALUE_TYPE c, cint;
6673
6674         c = TREE_REAL_CST (t);
6675         real_trunc (&cint, TYPE_MODE (TREE_TYPE (t)), &c);
6676         return real_identical (&c, &cint);
6677       }
6678
6679     case NOP_EXPR:
6680       {
6681         tree type = TREE_TYPE (TREE_OPERAND (t, 0));
6682         if (TREE_CODE (type) == INTEGER_TYPE)
6683           return true;
6684         if (TREE_CODE (type) == REAL_TYPE)
6685           return integer_valued_real_p (TREE_OPERAND (t, 0));
6686         break;
6687       }
6688
6689     case CALL_EXPR:
6690       switch (builtin_mathfn_code (t))
6691         {
6692         case BUILT_IN_CEIL:
6693         case BUILT_IN_CEILF:
6694         case BUILT_IN_CEILL:
6695         case BUILT_IN_FLOOR:
6696         case BUILT_IN_FLOORF:
6697         case BUILT_IN_FLOORL:
6698         case BUILT_IN_NEARBYINT:
6699         case BUILT_IN_NEARBYINTF:
6700         case BUILT_IN_NEARBYINTL:
6701         case BUILT_IN_RINT:
6702         case BUILT_IN_RINTF:
6703         case BUILT_IN_RINTL:
6704         case BUILT_IN_ROUND:
6705         case BUILT_IN_ROUNDF:
6706         case BUILT_IN_ROUNDL:
6707         case BUILT_IN_TRUNC:
6708         case BUILT_IN_TRUNCF:
6709         case BUILT_IN_TRUNCL:
6710           return true;
6711
6712         default:
6713           break;
6714         }
6715       break;
6716
6717     default:
6718       break;
6719     }
6720   return false;
6721 }
6722
6723 /* EXP is assumed to be builtin call where truncation can be propagated
6724    across (for instance floor((double)f) == (double)floorf (f).
6725    Do the transformation.  */
6726
6727 static tree
6728 fold_trunc_transparent_mathfn (tree fndecl, tree arglist)
6729 {
6730   enum built_in_function fcode = DECL_FUNCTION_CODE (fndecl);
6731   tree arg;
6732
6733   if (! validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
6734     return 0;
6735
6736   arg = TREE_VALUE (arglist);
6737   /* Integer rounding functions are idempotent.  */
6738   if (fcode == builtin_mathfn_code (arg))
6739     return arg;
6740
6741   /* If argument is already integer valued, and we don't need to worry
6742      about setting errno, there's no need to perform rounding.  */
6743   if (! flag_errno_math && integer_valued_real_p (arg))
6744     return arg;
6745
6746   if (optimize)
6747     {
6748       tree arg0 = strip_float_extensions (arg);
6749       tree ftype = TREE_TYPE (TREE_TYPE (fndecl));
6750       tree newtype = TREE_TYPE (arg0);
6751       tree decl;
6752
6753       if (TYPE_PRECISION (newtype) < TYPE_PRECISION (ftype)
6754           && (decl = mathfn_built_in (newtype, fcode)))
6755         {
6756           arglist =
6757             build_tree_list (NULL_TREE, fold_convert (newtype, arg0));
6758           return fold_convert (ftype,
6759                                build_function_call_expr (decl, arglist));
6760         }
6761     }
6762   return 0;
6763 }
6764
6765 /* EXP is assumed to be builtin call which can narrow the FP type of
6766    the argument, for instance lround((double)f) -> lroundf (f).  */
6767
6768 static tree
6769 fold_fixed_mathfn (tree fndecl, tree arglist)
6770 {
6771   enum built_in_function fcode = DECL_FUNCTION_CODE (fndecl);
6772   tree arg;
6773
6774   if (! validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
6775     return 0;
6776
6777   arg = TREE_VALUE (arglist);
6778
6779   /* If argument is already integer valued, and we don't need to worry
6780      about setting errno, there's no need to perform rounding.  */
6781   if (! flag_errno_math && integer_valued_real_p (arg))
6782     return fold_build1 (FIX_TRUNC_EXPR, TREE_TYPE (TREE_TYPE (fndecl)), arg);
6783
6784   if (optimize)
6785     {
6786       tree ftype = TREE_TYPE (arg);
6787       tree arg0 = strip_float_extensions (arg);
6788       tree newtype = TREE_TYPE (arg0);
6789       tree decl;
6790
6791       if (TYPE_PRECISION (newtype) < TYPE_PRECISION (ftype)
6792           && (decl = mathfn_built_in (newtype, fcode)))
6793         {
6794           arglist =
6795             build_tree_list (NULL_TREE, fold_convert (newtype, arg0));
6796           return build_function_call_expr (decl, arglist);
6797         }
6798     }
6799   return 0;
6800 }
6801
6802 /* Fold function call to builtin cabs, cabsf or cabsl.  ARGLIST
6803    is the argument list and TYPE is the return type.  Return
6804    NULL_TREE if no if no simplification can be made.  */
6805
6806 static tree
6807 fold_builtin_cabs (tree arglist, tree type)
6808 {
6809   tree arg;
6810
6811   if (!arglist || TREE_CHAIN (arglist))
6812     return NULL_TREE;
6813
6814   arg = TREE_VALUE (arglist);
6815   if (TREE_CODE (TREE_TYPE (arg)) != COMPLEX_TYPE
6816       || TREE_CODE (TREE_TYPE (TREE_TYPE (arg))) != REAL_TYPE)
6817     return NULL_TREE;
6818
6819   /* Evaluate cabs of a constant at compile-time.  */
6820   if (flag_unsafe_math_optimizations
6821       && TREE_CODE (arg) == COMPLEX_CST
6822       && TREE_CODE (TREE_REALPART (arg)) == REAL_CST
6823       && TREE_CODE (TREE_IMAGPART (arg)) == REAL_CST
6824       && ! TREE_CONSTANT_OVERFLOW (TREE_REALPART (arg))
6825       && ! TREE_CONSTANT_OVERFLOW (TREE_IMAGPART (arg)))
6826     {
6827       REAL_VALUE_TYPE r, i;
6828
6829       r = TREE_REAL_CST (TREE_REALPART (arg));
6830       i = TREE_REAL_CST (TREE_IMAGPART (arg));
6831
6832       real_arithmetic (&r, MULT_EXPR, &r, &r);
6833       real_arithmetic (&i, MULT_EXPR, &i, &i);
6834       real_arithmetic (&r, PLUS_EXPR, &r, &i);
6835       if (real_sqrt (&r, TYPE_MODE (type), &r)
6836           || ! flag_trapping_math)
6837         return build_real (type, r);
6838     }
6839
6840   /* If either part is zero, cabs is fabs of the other.  */
6841   if (TREE_CODE (arg) == COMPLEX_EXPR
6842       && real_zerop (TREE_OPERAND (arg, 0)))
6843     return fold_build1 (ABS_EXPR, type, TREE_OPERAND (arg, 1));
6844   if (TREE_CODE (arg) == COMPLEX_EXPR
6845       && real_zerop (TREE_OPERAND (arg, 1)))
6846     return fold_build1 (ABS_EXPR, type, TREE_OPERAND (arg, 0));
6847
6848   /* Don't do this when optimizing for size.  */
6849   if (flag_unsafe_math_optimizations
6850       && optimize && !optimize_size)
6851     {
6852       tree sqrtfn = mathfn_built_in (type, BUILT_IN_SQRT);
6853
6854       if (sqrtfn != NULL_TREE)
6855         {
6856           tree rpart, ipart, result, arglist;
6857
6858           arg = builtin_save_expr (arg);
6859
6860           rpart = fold_build1 (REALPART_EXPR, type, arg);
6861           ipart = fold_build1 (IMAGPART_EXPR, type, arg);
6862
6863           rpart = builtin_save_expr (rpart);
6864           ipart = builtin_save_expr (ipart);
6865
6866           result = fold_build2 (PLUS_EXPR, type,
6867                                 fold_build2 (MULT_EXPR, type,
6868                                              rpart, rpart),
6869                                 fold_build2 (MULT_EXPR, type,
6870                                              ipart, ipart));
6871
6872           arglist = build_tree_list (NULL_TREE, result);
6873           return build_function_call_expr (sqrtfn, arglist);
6874         }
6875     }
6876
6877   return NULL_TREE;
6878 }
6879
6880 /* Fold a builtin function call to sqrt, sqrtf, or sqrtl.  Return
6881    NULL_TREE if no simplification can be made.  */
6882
6883 static tree
6884 fold_builtin_sqrt (tree arglist, tree type)
6885 {
6886
6887   enum built_in_function fcode;
6888   tree arg = TREE_VALUE (arglist);
6889
6890   if (!validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
6891     return NULL_TREE;
6892
6893   /* Optimize sqrt of constant value.  */
6894   if (TREE_CODE (arg) == REAL_CST
6895       && ! TREE_CONSTANT_OVERFLOW (arg))
6896     {
6897       REAL_VALUE_TYPE r, x;
6898
6899       x = TREE_REAL_CST (arg);
6900       if (real_sqrt (&r, TYPE_MODE (type), &x)
6901           || (!flag_trapping_math && !flag_errno_math))
6902         return build_real (type, r);
6903     }
6904
6905   /* Optimize sqrt(expN(x)) = expN(x*0.5).  */
6906   fcode = builtin_mathfn_code (arg);
6907   if (flag_unsafe_math_optimizations && BUILTIN_EXPONENT_P (fcode))
6908     {
6909       tree expfn = TREE_OPERAND (TREE_OPERAND (arg, 0), 0);
6910       arg = fold_build2 (MULT_EXPR, type,
6911                          TREE_VALUE (TREE_OPERAND (arg, 1)),
6912                          build_real (type, dconsthalf));
6913       arglist = build_tree_list (NULL_TREE, arg);
6914       return build_function_call_expr (expfn, arglist);
6915     }
6916
6917   /* Optimize sqrt(Nroot(x)) -> pow(x,1/(2*N)).  */
6918   if (flag_unsafe_math_optimizations && BUILTIN_ROOT_P (fcode))
6919     {
6920       tree powfn = mathfn_built_in (type, BUILT_IN_POW);
6921
6922       if (powfn)
6923         {
6924           tree arg0 = TREE_VALUE (TREE_OPERAND (arg, 1));
6925           tree tree_root;
6926           /* The inner root was either sqrt or cbrt.  */
6927           REAL_VALUE_TYPE dconstroot =
6928             BUILTIN_SQRT_P (fcode) ? dconsthalf : dconstthird;
6929
6930           /* Adjust for the outer root.  */
6931           SET_REAL_EXP (&dconstroot, REAL_EXP (&dconstroot) - 1);
6932           dconstroot = real_value_truncate (TYPE_MODE (type), dconstroot);
6933           tree_root = build_real (type, dconstroot);
6934           arglist = tree_cons (NULL_TREE, arg0,
6935                                build_tree_list (NULL_TREE, tree_root));
6936           return build_function_call_expr (powfn, arglist);
6937         }
6938     }
6939
6940   /* Optimize sqrt(pow(x,y)) = pow(|x|,y*0.5).  */
6941   if (flag_unsafe_math_optimizations
6942       && (fcode == BUILT_IN_POW
6943           || fcode == BUILT_IN_POWF
6944           || fcode == BUILT_IN_POWL))
6945     {
6946       tree powfn = TREE_OPERAND (TREE_OPERAND (arg, 0), 0);
6947       tree arg0 = TREE_VALUE (TREE_OPERAND (arg, 1));
6948       tree arg1 = TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg, 1)));
6949       tree narg1;
6950       if (!tree_expr_nonnegative_p (arg0))
6951         arg0 = build1 (ABS_EXPR, type, arg0);
6952       narg1 = fold_build2 (MULT_EXPR, type, arg1,
6953                            build_real (type, dconsthalf));
6954       arglist = tree_cons (NULL_TREE, arg0,
6955                            build_tree_list (NULL_TREE, narg1));
6956       return build_function_call_expr (powfn, arglist);
6957     }
6958
6959   return NULL_TREE;
6960 }
6961
6962 /* Fold a builtin function call to cbrt, cbrtf, or cbrtl.  Return
6963    NULL_TREE if no simplification can be made.  */
6964 static tree
6965 fold_builtin_cbrt (tree arglist, tree type)
6966 {
6967   tree arg = TREE_VALUE (arglist);
6968   const enum built_in_function fcode = builtin_mathfn_code (arg);
6969
6970   if (!validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
6971     return NULL_TREE;
6972
6973   /* Optimize cbrt of constant value.  */
6974   if (real_zerop (arg) || real_onep (arg) || real_minus_onep (arg))
6975     return arg;
6976
6977   if (flag_unsafe_math_optimizations)
6978     {
6979       /* Optimize cbrt(expN(x)) -> expN(x/3).  */
6980       if (BUILTIN_EXPONENT_P (fcode))
6981         {
6982           tree expfn = TREE_OPERAND (TREE_OPERAND (arg, 0), 0);
6983           const REAL_VALUE_TYPE third_trunc =
6984             real_value_truncate (TYPE_MODE (type), dconstthird);
6985           arg = fold_build2 (MULT_EXPR, type,
6986                              TREE_VALUE (TREE_OPERAND (arg, 1)),
6987                              build_real (type, third_trunc));
6988           arglist = build_tree_list (NULL_TREE, arg);
6989           return build_function_call_expr (expfn, arglist);
6990         }
6991
6992       /* Optimize cbrt(sqrt(x)) -> pow(x,1/6).  */
6993       if (BUILTIN_SQRT_P (fcode))
6994         {
6995           tree powfn = mathfn_built_in (type, BUILT_IN_POW);
6996
6997           if (powfn)
6998             {
6999               tree arg0 = TREE_VALUE (TREE_OPERAND (arg, 1));
7000               tree tree_root;
7001               REAL_VALUE_TYPE dconstroot = dconstthird;
7002
7003               SET_REAL_EXP (&dconstroot, REAL_EXP (&dconstroot) - 1);
7004               dconstroot = real_value_truncate (TYPE_MODE (type), dconstroot);
7005               tree_root = build_real (type, dconstroot);
7006               arglist = tree_cons (NULL_TREE, arg0,
7007                                    build_tree_list (NULL_TREE, tree_root));
7008               return build_function_call_expr (powfn, arglist);
7009             }
7010         }
7011
7012       /* Optimize cbrt(cbrt(x)) -> pow(x,1/9) iff x is nonnegative.  */
7013       if (BUILTIN_CBRT_P (fcode))
7014         {
7015           tree arg0 = TREE_VALUE (TREE_OPERAND (arg, 1));
7016           if (tree_expr_nonnegative_p (arg0))
7017             {
7018               tree powfn = mathfn_built_in (type, BUILT_IN_POW);
7019
7020               if (powfn)
7021                 {
7022                   tree tree_root;
7023                   REAL_VALUE_TYPE dconstroot;
7024
7025                   real_arithmetic (&dconstroot, MULT_EXPR, &dconstthird, &dconstthird);
7026                   dconstroot = real_value_truncate (TYPE_MODE (type), dconstroot);
7027                   tree_root = build_real (type, dconstroot);
7028                   arglist = tree_cons (NULL_TREE, arg0,
7029                                        build_tree_list (NULL_TREE, tree_root));
7030                   return build_function_call_expr (powfn, arglist);
7031                 }
7032             }
7033         }
7034
7035       /* Optimize cbrt(pow(x,y)) -> pow(x,y/3) iff x is nonnegative.  */
7036       if (fcode == BUILT_IN_POW || fcode == BUILT_IN_POWF
7037           || fcode == BUILT_IN_POWL)
7038         {
7039           tree arg00 = TREE_VALUE (TREE_OPERAND (arg, 1));
7040           tree arg01 = TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg, 1)));
7041           if (tree_expr_nonnegative_p (arg00))
7042             {
7043               tree powfn = TREE_OPERAND (TREE_OPERAND (arg, 0), 0);
7044               const REAL_VALUE_TYPE dconstroot
7045                 = real_value_truncate (TYPE_MODE (type), dconstthird);
7046               tree narg01 = fold_build2 (MULT_EXPR, type, arg01,
7047                                          build_real (type, dconstroot));
7048               arglist = tree_cons (NULL_TREE, arg00,
7049                                    build_tree_list (NULL_TREE, narg01));
7050               return build_function_call_expr (powfn, arglist);
7051             }
7052         }
7053     }
7054   return NULL_TREE;
7055 }
7056
7057 /* Fold function call to builtin sin, sinf, or sinl.  Return
7058    NULL_TREE if no simplification can be made.  */
7059 static tree
7060 fold_builtin_sin (tree arglist)
7061 {
7062   tree arg = TREE_VALUE (arglist);
7063
7064   if (!validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
7065     return NULL_TREE;
7066
7067   /* Optimize sin (0.0) = 0.0.  */
7068   if (real_zerop (arg))
7069     return arg;
7070
7071   return NULL_TREE;
7072 }
7073
7074 /* Fold function call to builtin cos, cosf, or cosl.  Return
7075    NULL_TREE if no simplification can be made.  */
7076 static tree
7077 fold_builtin_cos (tree arglist, tree type, tree fndecl)
7078 {
7079   tree arg = TREE_VALUE (arglist);
7080
7081   if (!validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
7082     return NULL_TREE;
7083
7084   /* Optimize cos (0.0) = 1.0.  */
7085   if (real_zerop (arg))
7086     return build_real (type, dconst1);
7087
7088   /* Optimize cos(-x) into cos (x).  */
7089   if (TREE_CODE (arg) == NEGATE_EXPR)
7090     {
7091       tree args = build_tree_list (NULL_TREE,
7092                                    TREE_OPERAND (arg, 0));
7093       return build_function_call_expr (fndecl, args);
7094     }
7095
7096   return NULL_TREE;
7097 }
7098
7099 /* Fold function call to builtin tan, tanf, or tanl.  Return
7100    NULL_TREE if no simplification can be made.  */
7101 static tree
7102 fold_builtin_tan (tree arglist)
7103 {
7104   enum built_in_function fcode;
7105   tree arg = TREE_VALUE (arglist);
7106
7107   if (!validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
7108     return NULL_TREE;
7109
7110   /* Optimize tan(0.0) = 0.0.  */
7111   if (real_zerop (arg))
7112     return arg;
7113
7114   /* Optimize tan(atan(x)) = x.  */
7115   fcode = builtin_mathfn_code (arg);
7116   if (flag_unsafe_math_optimizations
7117       && (fcode == BUILT_IN_ATAN
7118           || fcode == BUILT_IN_ATANF
7119           || fcode == BUILT_IN_ATANL))
7120     return TREE_VALUE (TREE_OPERAND (arg, 1));
7121
7122   return NULL_TREE;
7123 }
7124
7125 /* Fold function call to builtin atan, atanf, or atanl.  Return
7126    NULL_TREE if no simplification can be made.  */
7127
7128 static tree
7129 fold_builtin_atan (tree arglist, tree type)
7130 {
7131
7132   tree arg = TREE_VALUE (arglist);
7133
7134   if (!validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
7135     return NULL_TREE;
7136
7137   /* Optimize atan(0.0) = 0.0.  */
7138   if (real_zerop (arg))
7139     return arg;
7140
7141   /* Optimize atan(1.0) = pi/4.  */
7142   if (real_onep (arg))
7143     {
7144       REAL_VALUE_TYPE cst;
7145
7146       real_convert (&cst, TYPE_MODE (type), &dconstpi);
7147       SET_REAL_EXP (&cst, REAL_EXP (&cst) - 2);
7148       return build_real (type, cst);
7149     }
7150
7151   return NULL_TREE;
7152 }
7153
7154 /* Fold function call to builtin trunc, truncf or truncl.  Return
7155    NULL_TREE if no simplification can be made.  */
7156
7157 static tree
7158 fold_builtin_trunc (tree fndecl, tree arglist)
7159 {
7160   tree arg;
7161
7162   if (! validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
7163     return 0;
7164
7165   /* Optimize trunc of constant value.  */
7166   arg = TREE_VALUE (arglist);
7167   if (TREE_CODE (arg) == REAL_CST && ! TREE_CONSTANT_OVERFLOW (arg))
7168     {
7169       REAL_VALUE_TYPE r, x;
7170       tree type = TREE_TYPE (TREE_TYPE (fndecl));
7171
7172       x = TREE_REAL_CST (arg);
7173       real_trunc (&r, TYPE_MODE (type), &x);
7174       return build_real (type, r);
7175     }
7176
7177   return fold_trunc_transparent_mathfn (fndecl, arglist);
7178 }
7179
7180 /* Fold function call to builtin floor, floorf or floorl.  Return
7181    NULL_TREE if no simplification can be made.  */
7182
7183 static tree
7184 fold_builtin_floor (tree fndecl, tree arglist)
7185 {
7186   tree arg;
7187
7188   if (! validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
7189     return 0;
7190
7191   /* Optimize floor of constant value.  */
7192   arg = TREE_VALUE (arglist);
7193   if (TREE_CODE (arg) == REAL_CST && ! TREE_CONSTANT_OVERFLOW (arg))
7194     {
7195       REAL_VALUE_TYPE x;
7196
7197       x = TREE_REAL_CST (arg);
7198       if (! REAL_VALUE_ISNAN (x) || ! flag_errno_math)
7199         {
7200           tree type = TREE_TYPE (TREE_TYPE (fndecl));
7201           REAL_VALUE_TYPE r;
7202
7203           real_floor (&r, TYPE_MODE (type), &x);
7204           return build_real (type, r);
7205         }
7206     }
7207
7208   return fold_trunc_transparent_mathfn (fndecl, arglist);
7209 }
7210
7211 /* Fold function call to builtin ceil, ceilf or ceill.  Return
7212    NULL_TREE if no simplification can be made.  */
7213
7214 static tree
7215 fold_builtin_ceil (tree fndecl, tree arglist)
7216 {
7217   tree arg;
7218
7219   if (! validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
7220     return 0;
7221
7222   /* Optimize ceil of constant value.  */
7223   arg = TREE_VALUE (arglist);
7224   if (TREE_CODE (arg) == REAL_CST && ! TREE_CONSTANT_OVERFLOW (arg))
7225     {
7226       REAL_VALUE_TYPE x;
7227
7228       x = TREE_REAL_CST (arg);
7229       if (! REAL_VALUE_ISNAN (x) || ! flag_errno_math)
7230         {
7231           tree type = TREE_TYPE (TREE_TYPE (fndecl));
7232           REAL_VALUE_TYPE r;
7233
7234           real_ceil (&r, TYPE_MODE (type), &x);
7235           return build_real (type, r);
7236         }
7237     }
7238
7239   return fold_trunc_transparent_mathfn (fndecl, arglist);
7240 }
7241
7242 /* Fold function call to builtin round, roundf or roundl.  Return
7243    NULL_TREE if no simplification can be made.  */
7244
7245 static tree
7246 fold_builtin_round (tree fndecl, tree arglist)
7247 {
7248   tree arg;
7249
7250   if (! validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
7251     return 0;
7252
7253   /* Optimize round of constant value.  */
7254   arg = TREE_VALUE (arglist);
7255   if (TREE_CODE (arg) == REAL_CST && ! TREE_CONSTANT_OVERFLOW (arg))
7256     {
7257       REAL_VALUE_TYPE x;
7258
7259       x = TREE_REAL_CST (arg);
7260       if (! REAL_VALUE_ISNAN (x) || ! flag_errno_math)
7261         {
7262           tree type = TREE_TYPE (TREE_TYPE (fndecl));
7263           REAL_VALUE_TYPE r;
7264
7265           real_round (&r, TYPE_MODE (type), &x);
7266           return build_real (type, r);
7267         }
7268     }
7269
7270   return fold_trunc_transparent_mathfn (fndecl, arglist);
7271 }
7272
7273 /* Fold function call to builtin lround, lroundf or lroundl (or the
7274    corresponding long long versions) and other rounding functions.
7275    Return NULL_TREE if no simplification can be made.  */
7276
7277 static tree
7278 fold_builtin_int_roundingfn (tree fndecl, tree arglist)
7279 {
7280   tree arg;
7281
7282   if (! validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
7283     return 0;
7284
7285   /* Optimize lround of constant value.  */
7286   arg = TREE_VALUE (arglist);
7287   if (TREE_CODE (arg) == REAL_CST && ! TREE_CONSTANT_OVERFLOW (arg))
7288     {
7289       const REAL_VALUE_TYPE x = TREE_REAL_CST (arg);
7290
7291       if (! REAL_VALUE_ISNAN (x) && ! REAL_VALUE_ISINF (x))
7292         {
7293           tree itype = TREE_TYPE (TREE_TYPE (fndecl));
7294           tree ftype = TREE_TYPE (arg), result;
7295           HOST_WIDE_INT hi, lo;
7296           REAL_VALUE_TYPE r;
7297
7298           switch (DECL_FUNCTION_CODE (fndecl))
7299             {
7300             case BUILT_IN_LFLOOR:
7301             case BUILT_IN_LFLOORF:
7302             case BUILT_IN_LFLOORL:
7303             case BUILT_IN_LLFLOOR:
7304             case BUILT_IN_LLFLOORF:
7305             case BUILT_IN_LLFLOORL:
7306               real_floor (&r, TYPE_MODE (ftype), &x);
7307               break;
7308
7309             case BUILT_IN_LCEIL:
7310             case BUILT_IN_LCEILF:
7311             case BUILT_IN_LCEILL:
7312             case BUILT_IN_LLCEIL:
7313             case BUILT_IN_LLCEILF:
7314             case BUILT_IN_LLCEILL:
7315               real_ceil (&r, TYPE_MODE (ftype), &x);
7316               break;
7317
7318             case BUILT_IN_LROUND:
7319             case BUILT_IN_LROUNDF:
7320             case BUILT_IN_LROUNDL:
7321             case BUILT_IN_LLROUND:
7322             case BUILT_IN_LLROUNDF:
7323             case BUILT_IN_LLROUNDL:
7324               real_round (&r, TYPE_MODE (ftype), &x);
7325               break;
7326
7327             default:
7328               gcc_unreachable ();
7329             }
7330
7331           REAL_VALUE_TO_INT (&lo, &hi, r);
7332           result = build_int_cst_wide (NULL_TREE, lo, hi);
7333           if (int_fits_type_p (result, itype))
7334             return fold_convert (itype, result);
7335         }
7336     }
7337
7338   return fold_fixed_mathfn (fndecl, arglist);
7339 }
7340
7341 /* Fold function call to builtin ffs, clz, ctz, popcount and parity
7342    and their long and long long variants (i.e. ffsl and ffsll).
7343    Return NULL_TREE if no simplification can be made.  */
7344
7345 static tree
7346 fold_builtin_bitop (tree fndecl, tree arglist)
7347 {
7348   tree arg;
7349
7350   if (! validate_arglist (arglist, INTEGER_TYPE, VOID_TYPE))
7351     return NULL_TREE;
7352
7353   /* Optimize for constant argument.  */
7354   arg = TREE_VALUE (arglist);
7355   if (TREE_CODE (arg) == INTEGER_CST && ! TREE_CONSTANT_OVERFLOW (arg))
7356     {
7357       HOST_WIDE_INT hi, width, result;
7358       unsigned HOST_WIDE_INT lo;
7359       tree type;
7360
7361       type = TREE_TYPE (arg);
7362       width = TYPE_PRECISION (type);
7363       lo = TREE_INT_CST_LOW (arg);
7364
7365       /* Clear all the bits that are beyond the type's precision.  */
7366       if (width > HOST_BITS_PER_WIDE_INT)
7367         {
7368           hi = TREE_INT_CST_HIGH (arg);
7369           if (width < 2 * HOST_BITS_PER_WIDE_INT)
7370             hi &= ~((HOST_WIDE_INT) (-1) >> (width - HOST_BITS_PER_WIDE_INT));
7371         }
7372       else
7373         {
7374           hi = 0;
7375           if (width < HOST_BITS_PER_WIDE_INT)
7376             lo &= ~((unsigned HOST_WIDE_INT) (-1) << width);
7377         }
7378
7379       switch (DECL_FUNCTION_CODE (fndecl))
7380         {
7381         case BUILT_IN_FFS:
7382         case BUILT_IN_FFSL:
7383         case BUILT_IN_FFSLL:
7384           if (lo != 0)
7385             result = exact_log2 (lo & -lo) + 1;
7386           else if (hi != 0)
7387             result = HOST_BITS_PER_WIDE_INT + exact_log2 (hi & -hi) + 1;
7388           else
7389             result = 0;
7390           break;
7391
7392         case BUILT_IN_CLZ:
7393         case BUILT_IN_CLZL:
7394         case BUILT_IN_CLZLL:
7395           if (hi != 0)
7396             result = width - floor_log2 (hi) - 1 - HOST_BITS_PER_WIDE_INT;
7397           else if (lo != 0)
7398             result = width - floor_log2 (lo) - 1;
7399           else if (! CLZ_DEFINED_VALUE_AT_ZERO (TYPE_MODE (type), result))
7400             result = width;
7401           break;
7402
7403         case BUILT_IN_CTZ:
7404         case BUILT_IN_CTZL:
7405         case BUILT_IN_CTZLL:
7406           if (lo != 0)
7407             result = exact_log2 (lo & -lo);
7408           else if (hi != 0)
7409             result = HOST_BITS_PER_WIDE_INT + exact_log2 (hi & -hi);
7410           else if (! CTZ_DEFINED_VALUE_AT_ZERO (TYPE_MODE (type), result))
7411             result = width;
7412           break;
7413
7414         case BUILT_IN_POPCOUNT:
7415         case BUILT_IN_POPCOUNTL:
7416         case BUILT_IN_POPCOUNTLL:
7417           result = 0;
7418           while (lo)
7419             result++, lo &= lo - 1;
7420           while (hi)
7421             result++, hi &= hi - 1;
7422           break;
7423
7424         case BUILT_IN_PARITY:
7425         case BUILT_IN_PARITYL:
7426         case BUILT_IN_PARITYLL:
7427           result = 0;
7428           while (lo)
7429             result++, lo &= lo - 1;
7430           while (hi)
7431             result++, hi &= hi - 1;
7432           result &= 1;
7433           break;
7434
7435         default:
7436           gcc_unreachable ();
7437         }
7438
7439       return build_int_cst (TREE_TYPE (TREE_TYPE (fndecl)), result);
7440     }
7441
7442   return NULL_TREE;
7443 }
7444
7445 /* Return true if EXPR is the real constant contained in VALUE.  */
7446
7447 static bool
7448 real_dconstp (tree expr, const REAL_VALUE_TYPE *value)
7449 {
7450   STRIP_NOPS (expr);
7451
7452   return ((TREE_CODE (expr) == REAL_CST
7453            && ! TREE_CONSTANT_OVERFLOW (expr)
7454            && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), *value))
7455           || (TREE_CODE (expr) == COMPLEX_CST
7456               && real_dconstp (TREE_REALPART (expr), value)
7457               && real_zerop (TREE_IMAGPART (expr))));
7458 }
7459
7460 /* A subroutine of fold_builtin to fold the various logarithmic
7461    functions.  EXP is the CALL_EXPR of a call to a builtin logN
7462    function.  VALUE is the base of the logN function.  */
7463
7464 static tree
7465 fold_builtin_logarithm (tree fndecl, tree arglist,
7466                         const REAL_VALUE_TYPE *value)
7467 {
7468   if (validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
7469     {
7470       tree type = TREE_TYPE (TREE_TYPE (fndecl));
7471       tree arg = TREE_VALUE (arglist);
7472       const enum built_in_function fcode = builtin_mathfn_code (arg);
7473
7474       /* Optimize logN(1.0) = 0.0.  */
7475       if (real_onep (arg))
7476         return build_real (type, dconst0);
7477
7478       /* Optimize logN(N) = 1.0.  If N can't be truncated to MODE
7479          exactly, then only do this if flag_unsafe_math_optimizations.  */
7480       if (exact_real_truncate (TYPE_MODE (type), value)
7481           || flag_unsafe_math_optimizations)
7482         {
7483           const REAL_VALUE_TYPE value_truncate =
7484             real_value_truncate (TYPE_MODE (type), *value);
7485           if (real_dconstp (arg, &value_truncate))
7486             return build_real (type, dconst1);
7487         }
7488
7489       /* Special case, optimize logN(expN(x)) = x.  */
7490       if (flag_unsafe_math_optimizations
7491           && ((value == &dconste
7492                && (fcode == BUILT_IN_EXP
7493                    || fcode == BUILT_IN_EXPF
7494                    || fcode == BUILT_IN_EXPL))
7495               || (value == &dconst2
7496                   && (fcode == BUILT_IN_EXP2
7497                       || fcode == BUILT_IN_EXP2F
7498                       || fcode == BUILT_IN_EXP2L))
7499               || (value == &dconst10 && (BUILTIN_EXP10_P (fcode)))))
7500         return fold_convert (type, TREE_VALUE (TREE_OPERAND (arg, 1)));
7501
7502       /* Optimize logN(func()) for various exponential functions.  We
7503          want to determine the value "x" and the power "exponent" in
7504          order to transform logN(x**exponent) into exponent*logN(x).  */
7505       if (flag_unsafe_math_optimizations)
7506         {
7507           tree exponent = 0, x = 0;
7508
7509           switch (fcode)
7510           {
7511           case BUILT_IN_EXP:
7512           case BUILT_IN_EXPF:
7513           case BUILT_IN_EXPL:
7514             /* Prepare to do logN(exp(exponent) -> exponent*logN(e).  */
7515             x = build_real (type,
7516                             real_value_truncate (TYPE_MODE (type), dconste));
7517             exponent = TREE_VALUE (TREE_OPERAND (arg, 1));
7518             break;
7519           case BUILT_IN_EXP2:
7520           case BUILT_IN_EXP2F:
7521           case BUILT_IN_EXP2L:
7522             /* Prepare to do logN(exp2(exponent) -> exponent*logN(2).  */
7523             x = build_real (type, dconst2);
7524             exponent = TREE_VALUE (TREE_OPERAND (arg, 1));
7525             break;
7526           case BUILT_IN_EXP10:
7527           case BUILT_IN_EXP10F:
7528           case BUILT_IN_EXP10L:
7529           case BUILT_IN_POW10:
7530           case BUILT_IN_POW10F:
7531           case BUILT_IN_POW10L:
7532             /* Prepare to do logN(exp10(exponent) -> exponent*logN(10).  */
7533             x = build_real (type, dconst10);
7534             exponent = TREE_VALUE (TREE_OPERAND (arg, 1));
7535             break;
7536           case BUILT_IN_SQRT:
7537           case BUILT_IN_SQRTF:
7538           case BUILT_IN_SQRTL:
7539             /* Prepare to do logN(sqrt(x) -> 0.5*logN(x).  */
7540             x = TREE_VALUE (TREE_OPERAND (arg, 1));
7541             exponent = build_real (type, dconsthalf);
7542             break;
7543           case BUILT_IN_CBRT:
7544           case BUILT_IN_CBRTF:
7545           case BUILT_IN_CBRTL:
7546             /* Prepare to do logN(cbrt(x) -> (1/3)*logN(x).  */
7547             x = TREE_VALUE (TREE_OPERAND (arg, 1));
7548             exponent = build_real (type, real_value_truncate (TYPE_MODE (type),
7549                                                               dconstthird));
7550             break;
7551           case BUILT_IN_POW:
7552           case BUILT_IN_POWF:
7553           case BUILT_IN_POWL:
7554             /* Prepare to do logN(pow(x,exponent) -> exponent*logN(x).  */
7555             x = TREE_VALUE (TREE_OPERAND (arg, 1));
7556             exponent = TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg, 1)));
7557             break;
7558           default:
7559             break;
7560           }
7561
7562           /* Now perform the optimization.  */
7563           if (x && exponent)
7564             {
7565               tree logfn;
7566               arglist = build_tree_list (NULL_TREE, x);
7567               logfn = build_function_call_expr (fndecl, arglist);
7568               return fold_build2 (MULT_EXPR, type, exponent, logfn);
7569             }
7570         }
7571     }
7572
7573   return 0;
7574 }
7575
7576 /* Fold a builtin function call to pow, powf, or powl.  Return
7577    NULL_TREE if no simplification can be made.  */
7578 static tree
7579 fold_builtin_pow (tree fndecl, tree arglist, tree type)
7580 {
7581   tree arg0 = TREE_VALUE (arglist);
7582   tree arg1 = TREE_VALUE (TREE_CHAIN (arglist));
7583
7584   if (!validate_arglist (arglist, REAL_TYPE, REAL_TYPE, VOID_TYPE))
7585     return NULL_TREE;
7586
7587   /* Optimize pow(1.0,y) = 1.0.  */
7588   if (real_onep (arg0))
7589     return omit_one_operand (type, build_real (type, dconst1), arg1);
7590
7591   if (TREE_CODE (arg1) == REAL_CST
7592       && ! TREE_CONSTANT_OVERFLOW (arg1))
7593     {
7594       REAL_VALUE_TYPE cint;
7595       REAL_VALUE_TYPE c;
7596       HOST_WIDE_INT n;
7597
7598       c = TREE_REAL_CST (arg1);
7599
7600       /* Optimize pow(x,0.0) = 1.0.  */
7601       if (REAL_VALUES_EQUAL (c, dconst0))
7602         return omit_one_operand (type, build_real (type, dconst1),
7603                                  arg0);
7604
7605       /* Optimize pow(x,1.0) = x.  */
7606       if (REAL_VALUES_EQUAL (c, dconst1))
7607         return arg0;
7608
7609       /* Optimize pow(x,-1.0) = 1.0/x.  */
7610       if (REAL_VALUES_EQUAL (c, dconstm1))
7611         return fold_build2 (RDIV_EXPR, type,
7612                             build_real (type, dconst1), arg0);
7613
7614       /* Optimize pow(x,0.5) = sqrt(x).  */
7615       if (flag_unsafe_math_optimizations
7616           && REAL_VALUES_EQUAL (c, dconsthalf))
7617         {
7618           tree sqrtfn = mathfn_built_in (type, BUILT_IN_SQRT);
7619
7620           if (sqrtfn != NULL_TREE)
7621             {
7622               tree arglist = build_tree_list (NULL_TREE, arg0);
7623               return build_function_call_expr (sqrtfn, arglist);
7624             }
7625         }
7626
7627       /* Check for an integer exponent.  */
7628       n = real_to_integer (&c);
7629       real_from_integer (&cint, VOIDmode, n, n < 0 ? -1 : 0, 0);
7630       if (real_identical (&c, &cint))
7631         {
7632           /* Attempt to evaluate pow at compile-time.  */
7633           if (TREE_CODE (arg0) == REAL_CST
7634               && ! TREE_CONSTANT_OVERFLOW (arg0))
7635             {
7636               REAL_VALUE_TYPE x;
7637               bool inexact;
7638
7639               x = TREE_REAL_CST (arg0);
7640               inexact = real_powi (&x, TYPE_MODE (type), &x, n);
7641               if (flag_unsafe_math_optimizations || !inexact)
7642                 return build_real (type, x);
7643             }
7644
7645           /* Strip sign ops from even integer powers.  */
7646           if ((n & 1) == 0 && flag_unsafe_math_optimizations)
7647             {
7648               tree narg0 = fold_strip_sign_ops (arg0);
7649               if (narg0)
7650                 {
7651                   arglist = build_tree_list (NULL_TREE, arg1);
7652                   arglist = tree_cons (NULL_TREE, narg0, arglist);
7653                   return build_function_call_expr (fndecl, arglist);
7654                 }
7655             }
7656         }
7657     }
7658
7659   if (flag_unsafe_math_optimizations)
7660     {
7661       const enum built_in_function fcode = builtin_mathfn_code (arg0);
7662
7663       /* Optimize pow(expN(x),y) = expN(x*y).  */
7664       if (BUILTIN_EXPONENT_P (fcode))
7665         {
7666           tree expfn = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
7667           tree arg = TREE_VALUE (TREE_OPERAND (arg0, 1));
7668           arg = fold_build2 (MULT_EXPR, type, arg, arg1);
7669           arglist = build_tree_list (NULL_TREE, arg);
7670           return build_function_call_expr (expfn, arglist);
7671         }
7672
7673       /* Optimize pow(sqrt(x),y) = pow(x,y*0.5).  */
7674       if (BUILTIN_SQRT_P (fcode))
7675         {
7676           tree narg0 = TREE_VALUE (TREE_OPERAND (arg0, 1));
7677           tree narg1 = fold_build2 (MULT_EXPR, type, arg1,
7678                                     build_real (type, dconsthalf));
7679
7680           arglist = tree_cons (NULL_TREE, narg0,
7681                                build_tree_list (NULL_TREE, narg1));
7682           return build_function_call_expr (fndecl, arglist);
7683         }
7684
7685       /* Optimize pow(cbrt(x),y) = pow(x,y/3) iff x is nonnegative.  */
7686       if (BUILTIN_CBRT_P (fcode))
7687         {
7688           tree arg = TREE_VALUE (TREE_OPERAND (arg0, 1));
7689           if (tree_expr_nonnegative_p (arg))
7690             {
7691               const REAL_VALUE_TYPE dconstroot
7692                 = real_value_truncate (TYPE_MODE (type), dconstthird);
7693               tree narg1 = fold_build2 (MULT_EXPR, type, arg1,
7694                                         build_real (type, dconstroot));
7695               arglist = tree_cons (NULL_TREE, arg,
7696                                    build_tree_list (NULL_TREE, narg1));
7697               return build_function_call_expr (fndecl, arglist);
7698             }
7699         }
7700
7701       /* Optimize pow(pow(x,y),z) = pow(x,y*z).  */
7702       if (fcode == BUILT_IN_POW || fcode == BUILT_IN_POWF
7703            || fcode == BUILT_IN_POWL)
7704         {
7705           tree arg00 = TREE_VALUE (TREE_OPERAND (arg0, 1));
7706           tree arg01 = TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg0, 1)));
7707           tree narg1 = fold_build2 (MULT_EXPR, type, arg01, arg1);
7708           arglist = tree_cons (NULL_TREE, arg00,
7709                                build_tree_list (NULL_TREE, narg1));
7710           return build_function_call_expr (fndecl, arglist);
7711         }
7712     }
7713
7714   return NULL_TREE;
7715 }
7716
7717 /* Fold a builtin function call to powi, powif, or powil.  Return
7718    NULL_TREE if no simplification can be made.  */
7719 static tree
7720 fold_builtin_powi (tree fndecl ATTRIBUTE_UNUSED, tree arglist, tree type)
7721 {
7722   tree arg0 = TREE_VALUE (arglist);
7723   tree arg1 = TREE_VALUE (TREE_CHAIN (arglist));
7724
7725   if (!validate_arglist (arglist, REAL_TYPE, INTEGER_TYPE, VOID_TYPE))
7726     return NULL_TREE;
7727
7728   /* Optimize pow(1.0,y) = 1.0.  */
7729   if (real_onep (arg0))
7730     return omit_one_operand (type, build_real (type, dconst1), arg1);
7731
7732   if (host_integerp (arg1, 0))
7733     {
7734       HOST_WIDE_INT c = TREE_INT_CST_LOW (arg1);
7735
7736       /* Evaluate powi at compile-time.  */
7737       if (TREE_CODE (arg0) == REAL_CST
7738           && ! TREE_CONSTANT_OVERFLOW (arg0))
7739         {
7740           REAL_VALUE_TYPE x;
7741           x = TREE_REAL_CST (arg0);
7742           real_powi (&x, TYPE_MODE (type), &x, c);
7743           return build_real (type, x);
7744         }
7745
7746       /* Optimize pow(x,0) = 1.0.  */
7747       if (c == 0)
7748         return omit_one_operand (type, build_real (type, dconst1),
7749                                  arg0);
7750
7751       /* Optimize pow(x,1) = x.  */
7752       if (c == 1)
7753         return arg0;
7754
7755       /* Optimize pow(x,-1) = 1.0/x.  */
7756       if (c == -1)
7757         return fold_build2 (RDIV_EXPR, type,
7758                            build_real (type, dconst1), arg0);
7759     }
7760
7761   return NULL_TREE;
7762 }
7763
7764 /* A subroutine of fold_builtin to fold the various exponent
7765    functions.  EXP is the CALL_EXPR of a call to a builtin function.
7766    VALUE is the value which will be raised to a power.  */
7767
7768 static tree
7769 fold_builtin_exponent (tree fndecl, tree arglist,
7770                        const REAL_VALUE_TYPE *value)
7771 {
7772   if (validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
7773     {
7774       tree type = TREE_TYPE (TREE_TYPE (fndecl));
7775       tree arg = TREE_VALUE (arglist);
7776
7777       /* Optimize exp*(0.0) = 1.0.  */
7778       if (real_zerop (arg))
7779         return build_real (type, dconst1);
7780
7781       /* Optimize expN(1.0) = N.  */
7782       if (real_onep (arg))
7783         {
7784           REAL_VALUE_TYPE cst;
7785
7786           real_convert (&cst, TYPE_MODE (type), value);
7787           return build_real (type, cst);
7788         }
7789
7790       /* Attempt to evaluate expN(integer) at compile-time.  */
7791       if (flag_unsafe_math_optimizations
7792           && TREE_CODE (arg) == REAL_CST
7793           && ! TREE_CONSTANT_OVERFLOW (arg))
7794         {
7795           REAL_VALUE_TYPE cint;
7796           REAL_VALUE_TYPE c;
7797           HOST_WIDE_INT n;
7798
7799           c = TREE_REAL_CST (arg);
7800           n = real_to_integer (&c);
7801           real_from_integer (&cint, VOIDmode, n,
7802                              n < 0 ? -1 : 0, 0);
7803           if (real_identical (&c, &cint))
7804             {
7805               REAL_VALUE_TYPE x;
7806
7807               real_powi (&x, TYPE_MODE (type), value, n);
7808               return build_real (type, x);
7809             }
7810         }
7811
7812       /* Optimize expN(logN(x)) = x.  */
7813       if (flag_unsafe_math_optimizations)
7814         {
7815           const enum built_in_function fcode = builtin_mathfn_code (arg);
7816
7817           if ((value == &dconste
7818                && (fcode == BUILT_IN_LOG
7819                    || fcode == BUILT_IN_LOGF
7820                    || fcode == BUILT_IN_LOGL))
7821               || (value == &dconst2
7822                   && (fcode == BUILT_IN_LOG2
7823                       || fcode == BUILT_IN_LOG2F
7824                       || fcode == BUILT_IN_LOG2L))
7825               || (value == &dconst10
7826                   && (fcode == BUILT_IN_LOG10
7827                       || fcode == BUILT_IN_LOG10F
7828                       || fcode == BUILT_IN_LOG10L)))
7829             return fold_convert (type, TREE_VALUE (TREE_OPERAND (arg, 1)));
7830         }
7831     }
7832
7833   return 0;
7834 }
7835
7836 /* Fold function call to builtin memcpy.  Return
7837    NULL_TREE if no simplification can be made.  */
7838
7839 static tree
7840 fold_builtin_memcpy (tree fndecl, tree arglist)
7841 {
7842   tree dest, src, len;
7843
7844   if (!validate_arglist (arglist,
7845                          POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
7846     return 0;
7847
7848   dest = TREE_VALUE (arglist);
7849   src = TREE_VALUE (TREE_CHAIN (arglist));
7850   len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
7851
7852   /* If the LEN parameter is zero, return DEST.  */
7853   if (integer_zerop (len))
7854     return omit_one_operand (TREE_TYPE (TREE_TYPE (fndecl)), dest, src);
7855
7856   /* If SRC and DEST are the same (and not volatile), return DEST.  */
7857   if (operand_equal_p (src, dest, 0))
7858     return omit_one_operand (TREE_TYPE (TREE_TYPE (fndecl)), dest, len);
7859
7860   return 0;
7861 }
7862
7863 /* Fold function call to builtin mempcpy.  Return
7864    NULL_TREE if no simplification can be made.  */
7865
7866 static tree
7867 fold_builtin_mempcpy (tree arglist, tree type, int endp)
7868 {
7869   if (validate_arglist (arglist,
7870                         POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
7871     {
7872       tree dest = TREE_VALUE (arglist);
7873       tree src = TREE_VALUE (TREE_CHAIN (arglist));
7874       tree len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
7875
7876       /* If the LEN parameter is zero, return DEST.  */
7877       if (integer_zerop (len))
7878         return omit_one_operand (type, dest, src);
7879
7880       /* If SRC and DEST are the same (and not volatile), return DEST+LEN.  */
7881       if (operand_equal_p (src, dest, 0))
7882         {
7883           if (endp == 0)
7884             return omit_one_operand (type, dest, len);
7885
7886           if (endp == 2)
7887             len = fold_build2 (MINUS_EXPR, TREE_TYPE (len), len,
7888                                ssize_int (1));
7889
7890           len = fold_convert (TREE_TYPE (dest), len);
7891           len = fold_build2 (PLUS_EXPR, TREE_TYPE (dest), dest, len);
7892           return fold_convert (type, len);
7893         }
7894     }
7895   return 0;
7896 }
7897
7898 /* Fold function call to builtin memmove.  Return
7899    NULL_TREE if no simplification can be made.  */
7900
7901 static tree
7902 fold_builtin_memmove (tree arglist, tree type)
7903 {
7904   tree dest, src, len;
7905
7906   if (!validate_arglist (arglist,
7907                          POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
7908     return 0;
7909
7910   dest = TREE_VALUE (arglist);
7911   src = TREE_VALUE (TREE_CHAIN (arglist));
7912   len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
7913
7914   /* If the LEN parameter is zero, return DEST.  */
7915   if (integer_zerop (len))
7916     return omit_one_operand (type, dest, src);
7917
7918   /* If SRC and DEST are the same (and not volatile), return DEST.  */
7919   if (operand_equal_p (src, dest, 0))
7920     return omit_one_operand (type, dest, len);
7921
7922   return 0;
7923 }
7924
7925 /* Fold function call to builtin strcpy.  If LEN is not NULL, it represents
7926    the length of the string to be copied.  Return NULL_TREE if no
7927    simplification can be made.  */
7928
7929 tree
7930 fold_builtin_strcpy (tree fndecl, tree arglist, tree len)
7931 {
7932   tree dest, src, fn;
7933
7934   if (!validate_arglist (arglist,
7935                          POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
7936     return 0;
7937
7938   dest = TREE_VALUE (arglist);
7939   src = TREE_VALUE (TREE_CHAIN (arglist));
7940
7941   /* If SRC and DEST are the same (and not volatile), return DEST.  */
7942   if (operand_equal_p (src, dest, 0))
7943     return fold_convert (TREE_TYPE (TREE_TYPE (fndecl)), dest);
7944
7945   if (optimize_size)
7946     return 0;
7947
7948   fn = implicit_built_in_decls[BUILT_IN_MEMCPY];
7949   if (!fn)
7950     return 0;
7951
7952   if (!len)
7953     {
7954       len = c_strlen (src, 1);
7955       if (! len || TREE_SIDE_EFFECTS (len))
7956         return 0;
7957     }
7958
7959   len = size_binop (PLUS_EXPR, len, ssize_int (1));
7960   arglist = build_tree_list (NULL_TREE, len);
7961   arglist = tree_cons (NULL_TREE, src, arglist);
7962   arglist = tree_cons (NULL_TREE, dest, arglist);
7963   return fold_convert (TREE_TYPE (TREE_TYPE (fndecl)),
7964                        build_function_call_expr (fn, arglist));
7965 }
7966
7967 /* Fold function call to builtin strncpy.  If SLEN is not NULL, it represents
7968    the length of the source string.  Return NULL_TREE if no simplification
7969    can be made.  */
7970
7971 tree
7972 fold_builtin_strncpy (tree fndecl, tree arglist, tree slen)
7973 {
7974   tree dest, src, len, fn;
7975
7976   if (!validate_arglist (arglist,
7977                          POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
7978     return 0;
7979
7980   dest = TREE_VALUE (arglist);
7981   src = TREE_VALUE (TREE_CHAIN (arglist));
7982   len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
7983
7984   /* If the LEN parameter is zero, return DEST.  */
7985   if (integer_zerop (len))
7986     return omit_one_operand (TREE_TYPE (TREE_TYPE (fndecl)), dest, src);
7987
7988   /* We can't compare slen with len as constants below if len is not a
7989      constant.  */
7990   if (len == 0 || TREE_CODE (len) != INTEGER_CST)
7991     return 0;
7992
7993   if (!slen)
7994     slen = c_strlen (src, 1);
7995
7996   /* Now, we must be passed a constant src ptr parameter.  */
7997   if (slen == 0 || TREE_CODE (slen) != INTEGER_CST)
7998     return 0;
7999
8000   slen = size_binop (PLUS_EXPR, slen, ssize_int (1));
8001
8002   /* We do not support simplification of this case, though we do
8003      support it when expanding trees into RTL.  */
8004   /* FIXME: generate a call to __builtin_memset.  */
8005   if (tree_int_cst_lt (slen, len))
8006     return 0;
8007
8008   /* OK transform into builtin memcpy.  */
8009   fn = implicit_built_in_decls[BUILT_IN_MEMCPY];
8010   if (!fn)
8011     return 0;
8012   return fold_convert (TREE_TYPE (TREE_TYPE (fndecl)),
8013                        build_function_call_expr (fn, arglist));
8014 }
8015
8016 /* Fold function call to builtin memcmp.  Return
8017    NULL_TREE if no simplification can be made.  */
8018
8019 static tree
8020 fold_builtin_memcmp (tree arglist)
8021 {
8022   tree arg1, arg2, len;
8023   const char *p1, *p2;
8024
8025   if (!validate_arglist (arglist,
8026                          POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
8027     return 0;
8028
8029   arg1 = TREE_VALUE (arglist);
8030   arg2 = TREE_VALUE (TREE_CHAIN (arglist));
8031   len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
8032
8033   /* If the LEN parameter is zero, return zero.  */
8034   if (integer_zerop (len))
8035     return omit_two_operands (integer_type_node, integer_zero_node,
8036                               arg1, arg2);
8037
8038   /* If ARG1 and ARG2 are the same (and not volatile), return zero.  */
8039   if (operand_equal_p (arg1, arg2, 0))
8040     return omit_one_operand (integer_type_node, integer_zero_node, len);
8041
8042   p1 = c_getstr (arg1);
8043   p2 = c_getstr (arg2);
8044
8045   /* If all arguments are constant, and the value of len is not greater
8046      than the lengths of arg1 and arg2, evaluate at compile-time.  */
8047   if (host_integerp (len, 1) && p1 && p2
8048       && compare_tree_int (len, strlen (p1) + 1) <= 0
8049       && compare_tree_int (len, strlen (p2) + 1) <= 0)
8050     {
8051       const int r = memcmp (p1, p2, tree_low_cst (len, 1));
8052
8053       if (r > 0)
8054         return integer_one_node;
8055       else if (r < 0)
8056         return integer_minus_one_node;
8057       else
8058         return integer_zero_node;
8059     }
8060
8061   /* If len parameter is one, return an expression corresponding to
8062      (*(const unsigned char*)arg1 - (const unsigned char*)arg2).  */
8063   if (host_integerp (len, 1) && tree_low_cst (len, 1) == 1)
8064     {
8065       tree cst_uchar_node = build_type_variant (unsigned_char_type_node, 1, 0);
8066       tree cst_uchar_ptr_node = build_pointer_type (cst_uchar_node);
8067       tree ind1 = fold_convert (integer_type_node,
8068                                 build1 (INDIRECT_REF, cst_uchar_node,
8069                                         fold_convert (cst_uchar_ptr_node,
8070                                                       arg1)));
8071       tree ind2 = fold_convert (integer_type_node,
8072                                 build1 (INDIRECT_REF, cst_uchar_node,
8073                                         fold_convert (cst_uchar_ptr_node,
8074                                                       arg2)));
8075       return fold_build2 (MINUS_EXPR, integer_type_node, ind1, ind2);
8076     }
8077
8078   return 0;
8079 }
8080
8081 /* Fold function call to builtin strcmp.  Return
8082    NULL_TREE if no simplification can be made.  */
8083
8084 static tree
8085 fold_builtin_strcmp (tree arglist)
8086 {
8087   tree arg1, arg2;
8088   const char *p1, *p2;
8089
8090   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
8091     return 0;
8092
8093   arg1 = TREE_VALUE (arglist);
8094   arg2 = TREE_VALUE (TREE_CHAIN (arglist));
8095
8096   /* If ARG1 and ARG2 are the same (and not volatile), return zero.  */
8097   if (operand_equal_p (arg1, arg2, 0))
8098     return integer_zero_node;
8099
8100   p1 = c_getstr (arg1);
8101   p2 = c_getstr (arg2);
8102
8103   if (p1 && p2)
8104     {
8105       const int i = strcmp (p1, p2);
8106       if (i < 0)
8107         return integer_minus_one_node;
8108       else if (i > 0)
8109         return integer_one_node;
8110       else
8111         return integer_zero_node;
8112     }
8113
8114   /* If the second arg is "", return *(const unsigned char*)arg1.  */
8115   if (p2 && *p2 == '\0')
8116     {
8117       tree cst_uchar_node = build_type_variant (unsigned_char_type_node, 1, 0);
8118       tree cst_uchar_ptr_node = build_pointer_type (cst_uchar_node);
8119       return fold_convert (integer_type_node,
8120                            build1 (INDIRECT_REF, cst_uchar_node,
8121                                    fold_convert (cst_uchar_ptr_node,
8122                                                  arg1)));
8123     }
8124
8125   /* If the first arg is "", return -*(const unsigned char*)arg2.  */
8126   if (p1 && *p1 == '\0')
8127     {
8128       tree cst_uchar_node = build_type_variant (unsigned_char_type_node, 1, 0);
8129       tree cst_uchar_ptr_node = build_pointer_type (cst_uchar_node);
8130       tree temp = fold_convert (integer_type_node,
8131                                 build1 (INDIRECT_REF, cst_uchar_node,
8132                                         fold_convert (cst_uchar_ptr_node,
8133                                                       arg2)));
8134       return fold_build1 (NEGATE_EXPR, integer_type_node, temp);
8135     }
8136
8137   return 0;
8138 }
8139
8140 /* Fold function call to builtin strncmp.  Return
8141    NULL_TREE if no simplification can be made.  */
8142
8143 static tree
8144 fold_builtin_strncmp (tree arglist)
8145 {
8146   tree arg1, arg2, len;
8147   const char *p1, *p2;
8148
8149   if (!validate_arglist (arglist,
8150                          POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
8151     return 0;
8152
8153   arg1 = TREE_VALUE (arglist);
8154   arg2 = TREE_VALUE (TREE_CHAIN (arglist));
8155   len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
8156
8157   /* If the LEN parameter is zero, return zero.  */
8158   if (integer_zerop (len))
8159     return omit_two_operands (integer_type_node, integer_zero_node,
8160                               arg1, arg2);
8161
8162   /* If ARG1 and ARG2 are the same (and not volatile), return zero.  */
8163   if (operand_equal_p (arg1, arg2, 0))
8164     return omit_one_operand (integer_type_node, integer_zero_node, len);
8165
8166   p1 = c_getstr (arg1);
8167   p2 = c_getstr (arg2);
8168
8169   if (host_integerp (len, 1) && p1 && p2)
8170     {
8171       const int i = strncmp (p1, p2, tree_low_cst (len, 1));
8172       if (i > 0)
8173         return integer_one_node;
8174       else if (i < 0)
8175         return integer_minus_one_node;
8176       else
8177         return integer_zero_node;
8178     }
8179
8180   /* If the second arg is "", and the length is greater than zero,
8181      return *(const unsigned char*)arg1.  */
8182   if (p2 && *p2 == '\0'
8183       && TREE_CODE (len) == INTEGER_CST
8184       && tree_int_cst_sgn (len) == 1)
8185     {
8186       tree cst_uchar_node = build_type_variant (unsigned_char_type_node, 1, 0);
8187       tree cst_uchar_ptr_node = build_pointer_type (cst_uchar_node);
8188       return fold_convert (integer_type_node,
8189                            build1 (INDIRECT_REF, cst_uchar_node,
8190                                    fold_convert (cst_uchar_ptr_node,
8191                                                  arg1)));
8192     }
8193
8194   /* If the first arg is "", and the length is greater than zero,
8195      return -*(const unsigned char*)arg2.  */
8196   if (p1 && *p1 == '\0'
8197       && TREE_CODE (len) == INTEGER_CST
8198       && tree_int_cst_sgn (len) == 1)
8199     {
8200       tree cst_uchar_node = build_type_variant (unsigned_char_type_node, 1, 0);
8201       tree cst_uchar_ptr_node = build_pointer_type (cst_uchar_node);
8202       tree temp = fold_convert (integer_type_node,
8203                                 build1 (INDIRECT_REF, cst_uchar_node,
8204                                         fold_convert (cst_uchar_ptr_node,
8205                                                       arg2)));
8206       return fold_build1 (NEGATE_EXPR, integer_type_node, temp);
8207     }
8208
8209   /* If len parameter is one, return an expression corresponding to
8210      (*(const unsigned char*)arg1 - (const unsigned char*)arg2).  */
8211   if (host_integerp (len, 1) && tree_low_cst (len, 1) == 1)
8212     {
8213       tree cst_uchar_node = build_type_variant (unsigned_char_type_node, 1, 0);
8214       tree cst_uchar_ptr_node = build_pointer_type (cst_uchar_node);
8215       tree ind1 = fold_convert (integer_type_node,
8216                                 build1 (INDIRECT_REF, cst_uchar_node,
8217                                         fold_convert (cst_uchar_ptr_node,
8218                                                       arg1)));
8219       tree ind2 = fold_convert (integer_type_node,
8220                                 build1 (INDIRECT_REF, cst_uchar_node,
8221                                         fold_convert (cst_uchar_ptr_node,
8222                                                       arg2)));
8223       return fold_build2 (MINUS_EXPR, integer_type_node, ind1, ind2);
8224     }
8225
8226   return 0;
8227 }
8228
8229 /* Fold function call to builtin signbit, signbitf or signbitl.  Return
8230    NULL_TREE if no simplification can be made.  */
8231
8232 static tree
8233 fold_builtin_signbit (tree fndecl, tree arglist)
8234 {
8235   tree type = TREE_TYPE (TREE_TYPE (fndecl));
8236   tree arg, temp;
8237
8238   if (!validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
8239     return NULL_TREE;
8240
8241   arg = TREE_VALUE (arglist);
8242
8243   /* If ARG is a compile-time constant, determine the result.  */
8244   if (TREE_CODE (arg) == REAL_CST
8245       && !TREE_CONSTANT_OVERFLOW (arg))
8246     {
8247       REAL_VALUE_TYPE c;
8248
8249       c = TREE_REAL_CST (arg);
8250       temp = REAL_VALUE_NEGATIVE (c) ? integer_one_node : integer_zero_node;
8251       return fold_convert (type, temp);
8252     }
8253
8254   /* If ARG is non-negative, the result is always zero.  */
8255   if (tree_expr_nonnegative_p (arg))
8256     return omit_one_operand (type, integer_zero_node, arg);
8257
8258   /* If ARG's format doesn't have signed zeros, return "arg < 0.0".  */
8259   if (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg))))
8260     return fold_build2 (LT_EXPR, type, arg,
8261                         build_real (TREE_TYPE (arg), dconst0));
8262
8263   return NULL_TREE;
8264 }
8265
8266 /* Fold function call to builtin copysign, copysignf or copysignl.
8267    Return NULL_TREE if no simplification can be made.  */
8268
8269 static tree
8270 fold_builtin_copysign (tree fndecl, tree arglist, tree type)
8271 {
8272   tree arg1, arg2, tem;
8273
8274   if (!validate_arglist (arglist, REAL_TYPE, REAL_TYPE, VOID_TYPE))
8275     return NULL_TREE;
8276
8277   arg1 = TREE_VALUE (arglist);
8278   arg2 = TREE_VALUE (TREE_CHAIN (arglist));
8279
8280   /* copysign(X,X) is X.  */
8281   if (operand_equal_p (arg1, arg2, 0))
8282     return fold_convert (type, arg1);
8283
8284   /* If ARG1 and ARG2 are compile-time constants, determine the result.  */
8285   if (TREE_CODE (arg1) == REAL_CST
8286       && TREE_CODE (arg2) == REAL_CST
8287       && !TREE_CONSTANT_OVERFLOW (arg1)
8288       && !TREE_CONSTANT_OVERFLOW (arg2))
8289     {
8290       REAL_VALUE_TYPE c1, c2;
8291
8292       c1 = TREE_REAL_CST (arg1);
8293       c2 = TREE_REAL_CST (arg2);
8294       real_copysign (&c1, &c2);
8295       return build_real (type, c1);
8296       c1.sign = c2.sign;
8297     }
8298
8299   /* copysign(X, Y) is fabs(X) when Y is always non-negative.
8300      Remember to evaluate Y for side-effects.  */
8301   if (tree_expr_nonnegative_p (arg2))
8302     return omit_one_operand (type,
8303                              fold_build1 (ABS_EXPR, type, arg1),
8304                              arg2);
8305
8306   /* Strip sign changing operations for the first argument.  */
8307   tem = fold_strip_sign_ops (arg1);
8308   if (tem)
8309     {
8310       arglist = tree_cons (NULL_TREE, tem, TREE_CHAIN (arglist));
8311       return build_function_call_expr (fndecl, arglist);
8312     }
8313
8314   return NULL_TREE;
8315 }
8316
8317 /* Fold a call to builtin isascii.  */
8318
8319 static tree
8320 fold_builtin_isascii (tree arglist)
8321 {
8322   if (! validate_arglist (arglist, INTEGER_TYPE, VOID_TYPE))
8323     return 0;
8324   else
8325     {
8326       /* Transform isascii(c) -> ((c & ~0x7f) == 0).  */
8327       tree arg = TREE_VALUE (arglist);
8328
8329       arg = build2 (BIT_AND_EXPR, integer_type_node, arg,
8330                     build_int_cst (NULL_TREE,
8331                                    ~ (unsigned HOST_WIDE_INT) 0x7f));
8332       arg = fold_build2 (EQ_EXPR, integer_type_node,
8333                          arg, integer_zero_node);
8334
8335       if (in_gimple_form && !TREE_CONSTANT (arg))
8336         return NULL_TREE;
8337       else
8338         return arg;
8339     }
8340 }
8341
8342 /* Fold a call to builtin toascii.  */
8343
8344 static tree
8345 fold_builtin_toascii (tree arglist)
8346 {
8347   if (! validate_arglist (arglist, INTEGER_TYPE, VOID_TYPE))
8348     return 0;
8349   else
8350     {
8351       /* Transform toascii(c) -> (c & 0x7f).  */
8352       tree arg = TREE_VALUE (arglist);
8353
8354       return fold_build2 (BIT_AND_EXPR, integer_type_node, arg,
8355                           build_int_cst (NULL_TREE, 0x7f));
8356     }
8357 }
8358
8359 /* Fold a call to builtin isdigit.  */
8360
8361 static tree
8362 fold_builtin_isdigit (tree arglist)
8363 {
8364   if (! validate_arglist (arglist, INTEGER_TYPE, VOID_TYPE))
8365     return 0;
8366   else
8367     {
8368       /* Transform isdigit(c) -> (unsigned)(c) - '0' <= 9.  */
8369       /* According to the C standard, isdigit is unaffected by locale.
8370          However, it definitely is affected by the target character set.  */
8371       tree arg;
8372       unsigned HOST_WIDE_INT target_digit0
8373         = lang_hooks.to_target_charset ('0');
8374
8375       if (target_digit0 == 0)
8376         return NULL_TREE;
8377
8378       arg = fold_convert (unsigned_type_node, TREE_VALUE (arglist));
8379       arg = build2 (MINUS_EXPR, unsigned_type_node, arg,
8380                     build_int_cst (unsigned_type_node, target_digit0));
8381       arg = fold_build2 (LE_EXPR, integer_type_node, arg,
8382                          build_int_cst (unsigned_type_node, 9));
8383       if (in_gimple_form && !TREE_CONSTANT (arg))
8384         return NULL_TREE;
8385       else
8386         return arg;
8387     }
8388 }
8389
8390 /* Fold a call to fabs, fabsf or fabsl.  */
8391
8392 static tree
8393 fold_builtin_fabs (tree arglist, tree type)
8394 {
8395   tree arg;
8396
8397   if (!validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
8398     return 0;
8399
8400   arg = TREE_VALUE (arglist);
8401   arg = fold_convert (type, arg);
8402   if (TREE_CODE (arg) == REAL_CST)
8403     return fold_abs_const (arg, type);
8404   return fold_build1 (ABS_EXPR, type, arg);
8405 }
8406
8407 /* Fold a call to abs, labs, llabs or imaxabs.  */
8408
8409 static tree
8410 fold_builtin_abs (tree arglist, tree type)
8411 {
8412   tree arg;
8413
8414   if (!validate_arglist (arglist, INTEGER_TYPE, VOID_TYPE))
8415     return 0;
8416
8417   arg = TREE_VALUE (arglist);
8418   arg = fold_convert (type, arg);
8419   if (TREE_CODE (arg) == INTEGER_CST)
8420     return fold_abs_const (arg, type);
8421   return fold_build1 (ABS_EXPR, type, arg);
8422 }
8423
8424 /* Fold a call to __builtin_isnan(), __builtin_isinf, __builtin_finite.
8425    EXP is the CALL_EXPR for the call.  */
8426
8427 static tree
8428 fold_builtin_classify (tree fndecl, tree arglist, int builtin_index)
8429 {
8430   tree type = TREE_TYPE (TREE_TYPE (fndecl));
8431   tree arg;
8432   REAL_VALUE_TYPE r;
8433
8434   if (!validate_arglist (arglist, REAL_TYPE, VOID_TYPE))
8435     {
8436       /* Check that we have exactly one argument.  */
8437       if (arglist == 0)
8438         {
8439           error ("too few arguments to function %qs",
8440                  IDENTIFIER_POINTER (DECL_NAME (fndecl)));
8441           return error_mark_node;
8442         }
8443       else if (TREE_CHAIN (arglist) != 0)
8444         {
8445           error ("too many arguments to function %qs",
8446                  IDENTIFIER_POINTER (DECL_NAME (fndecl)));
8447           return error_mark_node;
8448         }
8449       else
8450         {
8451           error ("non-floating-point argument to function %qs",
8452                  IDENTIFIER_POINTER (DECL_NAME (fndecl)));
8453           return error_mark_node;
8454         }
8455     }
8456
8457   arg = TREE_VALUE (arglist);
8458   switch (builtin_index)
8459     {
8460     case BUILT_IN_ISINF:
8461       if (!MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg))))
8462         return omit_one_operand (type, integer_zero_node, arg);
8463
8464       if (TREE_CODE (arg) == REAL_CST)
8465         {
8466           r = TREE_REAL_CST (arg);
8467           if (real_isinf (&r))
8468             return real_compare (GT_EXPR, &r, &dconst0)
8469                    ? integer_one_node : integer_minus_one_node;
8470           else
8471             return integer_zero_node;
8472         }
8473
8474       return NULL_TREE;
8475
8476     case BUILT_IN_FINITE:
8477       if (!MODE_HAS_NANS (TYPE_MODE (TREE_TYPE (arg)))
8478           && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg))))
8479         return omit_one_operand (type, integer_zero_node, arg);
8480
8481       if (TREE_CODE (arg) == REAL_CST)
8482         {
8483           r = TREE_REAL_CST (arg);
8484           return real_isinf (&r) || real_isnan (&r)
8485                  ? integer_zero_node : integer_one_node;
8486         }
8487
8488       return NULL_TREE;
8489
8490     case BUILT_IN_ISNAN:
8491       if (!MODE_HAS_NANS (TYPE_MODE (TREE_TYPE (arg))))
8492         return omit_one_operand (type, integer_zero_node, arg);
8493
8494       if (TREE_CODE (arg) == REAL_CST)
8495         {
8496           r = TREE_REAL_CST (arg);
8497           return real_isnan (&r) ? integer_one_node : integer_zero_node;
8498         }
8499
8500       arg = builtin_save_expr (arg);
8501       return fold_build2 (UNORDERED_EXPR, type, arg, arg);
8502
8503     default:
8504       gcc_unreachable ();
8505     }
8506 }
8507
8508 /* Fold a call to an unordered comparison function such as
8509    __builtin_isgreater().  FNDECL is the FUNCTION_DECL for the function
8510    being called and ARGLIST is the argument list for the call.
8511    UNORDERED_CODE and ORDERED_CODE are comparison codes that give
8512    the opposite of the desired result.  UNORDERED_CODE is used
8513    for modes that can hold NaNs and ORDERED_CODE is used for
8514    the rest.  */
8515
8516 static tree
8517 fold_builtin_unordered_cmp (tree fndecl, tree arglist,
8518                             enum tree_code unordered_code,
8519                             enum tree_code ordered_code)
8520 {
8521   tree type = TREE_TYPE (TREE_TYPE (fndecl));
8522   enum tree_code code;
8523   tree arg0, arg1;
8524   tree type0, type1;
8525   enum tree_code code0, code1;
8526   tree cmp_type = NULL_TREE;
8527
8528   if (!validate_arglist (arglist, REAL_TYPE, REAL_TYPE, VOID_TYPE))
8529     {
8530       /* Check that we have exactly two arguments.  */
8531       if (arglist == 0 || TREE_CHAIN (arglist) == 0)
8532         {
8533           error ("too few arguments to function %qs",
8534                  IDENTIFIER_POINTER (DECL_NAME (fndecl)));
8535           return error_mark_node;
8536         }
8537       else if (TREE_CHAIN (TREE_CHAIN (arglist)) != 0)
8538         {
8539           error ("too many arguments to function %qs",
8540                  IDENTIFIER_POINTER (DECL_NAME (fndecl)));
8541           return error_mark_node;
8542         }
8543     }
8544
8545   arg0 = TREE_VALUE (arglist);
8546   arg1 = TREE_VALUE (TREE_CHAIN (arglist));
8547
8548   type0 = TREE_TYPE (arg0);
8549   type1 = TREE_TYPE (arg1);
8550
8551   code0 = TREE_CODE (type0);
8552   code1 = TREE_CODE (type1);
8553
8554   if (code0 == REAL_TYPE && code1 == REAL_TYPE)
8555     /* Choose the wider of two real types.  */
8556     cmp_type = TYPE_PRECISION (type0) >= TYPE_PRECISION (type1)
8557       ? type0 : type1;
8558   else if (code0 == REAL_TYPE && code1 == INTEGER_TYPE)
8559     cmp_type = type0;
8560   else if (code0 == INTEGER_TYPE && code1 == REAL_TYPE)
8561     cmp_type = type1;
8562   else
8563     {
8564       error ("non-floating-point argument to function %qs",
8565                  IDENTIFIER_POINTER (DECL_NAME (fndecl)));
8566       return error_mark_node;
8567     }
8568
8569   arg0 = fold_convert (cmp_type, arg0);
8570   arg1 = fold_convert (cmp_type, arg1);
8571
8572   if (unordered_code == UNORDERED_EXPR)
8573     {
8574       if (!MODE_HAS_NANS (TYPE_MODE (TREE_TYPE (arg0))))
8575         return omit_two_operands (type, integer_zero_node, arg0, arg1);
8576       return fold_build2 (UNORDERED_EXPR, type, arg0, arg1);
8577     }
8578
8579   code = MODE_HAS_NANS (TYPE_MODE (TREE_TYPE (arg0))) ? unordered_code
8580                                                       : ordered_code;
8581   return fold_build1 (TRUTH_NOT_EXPR, type,
8582                       fold_build2 (code, type, arg0, arg1));
8583 }
8584
8585 /* Used by constant folding to simplify calls to builtin functions.  EXP is
8586    the CALL_EXPR of a call to a builtin function.  IGNORE is true if the
8587    result of the function call is ignored.  This function returns NULL_TREE
8588    if no simplification was possible.  */
8589
8590 static tree
8591 fold_builtin_1 (tree fndecl, tree arglist, bool ignore)
8592 {
8593   tree type = TREE_TYPE (TREE_TYPE (fndecl));
8594   enum built_in_function fcode;
8595
8596   if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_MD)
8597     return targetm.fold_builtin (fndecl, arglist, ignore);
8598
8599   fcode = DECL_FUNCTION_CODE (fndecl);
8600   switch (fcode)
8601     {
8602     case BUILT_IN_FPUTS:
8603       return fold_builtin_fputs (arglist, ignore, false, NULL_TREE);
8604
8605     case BUILT_IN_FPUTS_UNLOCKED:
8606       return fold_builtin_fputs (arglist, ignore, true, NULL_TREE);
8607
8608     case BUILT_IN_STRSTR:
8609       return fold_builtin_strstr (arglist, type);
8610
8611     case BUILT_IN_STRCAT:
8612       return fold_builtin_strcat (arglist);
8613
8614     case BUILT_IN_STRNCAT:
8615       return fold_builtin_strncat (arglist);
8616
8617     case BUILT_IN_STRSPN:
8618       return fold_builtin_strspn (arglist);
8619
8620     case BUILT_IN_STRCSPN:
8621       return fold_builtin_strcspn (arglist);
8622
8623     case BUILT_IN_STRCHR:
8624     case BUILT_IN_INDEX:
8625       return fold_builtin_strchr (arglist, type);
8626
8627     case BUILT_IN_STRRCHR:
8628     case BUILT_IN_RINDEX:
8629       return fold_builtin_strrchr (arglist, type);
8630
8631     case BUILT_IN_STRCPY:
8632       return fold_builtin_strcpy (fndecl, arglist, NULL_TREE);
8633
8634     case BUILT_IN_STRNCPY:
8635       return fold_builtin_strncpy (fndecl, arglist, NULL_TREE);
8636
8637     case BUILT_IN_STRCMP:
8638       return fold_builtin_strcmp (arglist);
8639
8640     case BUILT_IN_STRNCMP:
8641       return fold_builtin_strncmp (arglist);
8642
8643     case BUILT_IN_STRPBRK:
8644       return fold_builtin_strpbrk (arglist, type);
8645
8646     case BUILT_IN_BCMP:
8647     case BUILT_IN_MEMCMP:
8648       return fold_builtin_memcmp (arglist);
8649
8650     case BUILT_IN_SPRINTF:
8651       return fold_builtin_sprintf (arglist, ignore);
8652
8653     case BUILT_IN_CONSTANT_P:
8654       {
8655         tree val;
8656
8657         val = fold_builtin_constant_p (arglist);
8658         /* Gimplification will pull the CALL_EXPR for the builtin out of
8659            an if condition.  When not optimizing, we'll not CSE it back.
8660            To avoid link error types of regressions, return false now.  */
8661         if (!val && !optimize)
8662           val = integer_zero_node;
8663
8664         return val;
8665       }
8666
8667     case BUILT_IN_EXPECT:
8668       return fold_builtin_expect (arglist);
8669
8670     case BUILT_IN_CLASSIFY_TYPE:
8671       return fold_builtin_classify_type (arglist);
8672
8673     case BUILT_IN_STRLEN:
8674       return fold_builtin_strlen (arglist);
8675
8676     case BUILT_IN_FABS:
8677     case BUILT_IN_FABSF:
8678     case BUILT_IN_FABSL:
8679       return fold_builtin_fabs (arglist, type);
8680
8681     case BUILT_IN_ABS:
8682     case BUILT_IN_LABS:
8683     case BUILT_IN_LLABS:
8684     case BUILT_IN_IMAXABS:
8685       return fold_builtin_abs (arglist, type);
8686
8687     case BUILT_IN_CONJ:
8688     case BUILT_IN_CONJF:
8689     case BUILT_IN_CONJL:
8690       if (validate_arglist (arglist, COMPLEX_TYPE, VOID_TYPE))
8691         return fold_build1 (CONJ_EXPR, type, TREE_VALUE (arglist));
8692       break;
8693
8694     case BUILT_IN_CREAL:
8695     case BUILT_IN_CREALF:
8696     case BUILT_IN_CREALL:
8697       if (validate_arglist (arglist, COMPLEX_TYPE, VOID_TYPE))
8698         return non_lvalue (fold_build1 (REALPART_EXPR, type,
8699                                         TREE_VALUE (arglist)));
8700       break;
8701
8702     case BUILT_IN_CIMAG:
8703     case BUILT_IN_CIMAGF:
8704     case BUILT_IN_CIMAGL:
8705       if (validate_arglist (arglist, COMPLEX_TYPE, VOID_TYPE))
8706         return non_lvalue (fold_build1 (IMAGPART_EXPR, type,
8707                                         TREE_VALUE (arglist)));
8708       break;
8709
8710     case BUILT_IN_CABS:
8711     case BUILT_IN_CABSF:
8712     case BUILT_IN_CABSL:
8713       return fold_builtin_cabs (arglist, type);
8714
8715     case BUILT_IN_SQRT:
8716     case BUILT_IN_SQRTF:
8717     case BUILT_IN_SQRTL:
8718       return fold_builtin_sqrt (arglist, type);
8719
8720     case BUILT_IN_CBRT:
8721     case BUILT_IN_CBRTF:
8722     case BUILT_IN_CBRTL:
8723       return fold_builtin_cbrt (arglist, type);
8724
8725     case BUILT_IN_SIN:
8726     case BUILT_IN_SINF:
8727     case BUILT_IN_SINL:
8728       return fold_builtin_sin (arglist);
8729
8730     case BUILT_IN_COS:
8731     case BUILT_IN_COSF:
8732     case BUILT_IN_COSL:
8733       return fold_builtin_cos (arglist, type, fndecl);
8734
8735     case BUILT_IN_EXP:
8736     case BUILT_IN_EXPF:
8737     case BUILT_IN_EXPL:
8738       return fold_builtin_exponent (fndecl, arglist, &dconste);
8739
8740     case BUILT_IN_EXP2:
8741     case BUILT_IN_EXP2F:
8742     case BUILT_IN_EXP2L:
8743       return fold_builtin_exponent (fndecl, arglist, &dconst2);
8744
8745     case BUILT_IN_EXP10:
8746     case BUILT_IN_EXP10F:
8747     case BUILT_IN_EXP10L:
8748     case BUILT_IN_POW10:
8749     case BUILT_IN_POW10F:
8750     case BUILT_IN_POW10L:
8751       return fold_builtin_exponent (fndecl, arglist, &dconst10);
8752
8753     case BUILT_IN_LOG:
8754     case BUILT_IN_LOGF:
8755     case BUILT_IN_LOGL:
8756       return fold_builtin_logarithm (fndecl, arglist, &dconste);
8757
8758     case BUILT_IN_LOG2:
8759     case BUILT_IN_LOG2F:
8760     case BUILT_IN_LOG2L:
8761       return fold_builtin_logarithm (fndecl, arglist, &dconst2);
8762
8763     case BUILT_IN_LOG10:
8764     case BUILT_IN_LOG10F:
8765     case BUILT_IN_LOG10L:
8766       return fold_builtin_logarithm (fndecl, arglist, &dconst10);
8767
8768     case BUILT_IN_TAN:
8769     case BUILT_IN_TANF:
8770     case BUILT_IN_TANL:
8771       return fold_builtin_tan (arglist);
8772
8773     case BUILT_IN_ATAN:
8774     case BUILT_IN_ATANF:
8775     case BUILT_IN_ATANL:
8776       return fold_builtin_atan (arglist, type);
8777
8778     case BUILT_IN_POW:
8779     case BUILT_IN_POWF:
8780     case BUILT_IN_POWL:
8781       return fold_builtin_pow (fndecl, arglist, type);
8782
8783     case BUILT_IN_POWI:
8784     case BUILT_IN_POWIF:
8785     case BUILT_IN_POWIL:
8786       return fold_builtin_powi (fndecl, arglist, type);
8787
8788     case BUILT_IN_INF:
8789     case BUILT_IN_INFF:
8790     case BUILT_IN_INFL:
8791       return fold_builtin_inf (type, true);
8792
8793     case BUILT_IN_HUGE_VAL:
8794     case BUILT_IN_HUGE_VALF:
8795     case BUILT_IN_HUGE_VALL:
8796       return fold_builtin_inf (type, false);
8797
8798     case BUILT_IN_NAN:
8799     case BUILT_IN_NANF:
8800     case BUILT_IN_NANL:
8801       return fold_builtin_nan (arglist, type, true);
8802
8803     case BUILT_IN_NANS:
8804     case BUILT_IN_NANSF:
8805     case BUILT_IN_NANSL:
8806       return fold_builtin_nan (arglist, type, false);
8807
8808     case BUILT_IN_FLOOR:
8809     case BUILT_IN_FLOORF:
8810     case BUILT_IN_FLOORL:
8811       return fold_builtin_floor (fndecl, arglist);
8812
8813     case BUILT_IN_CEIL:
8814     case BUILT_IN_CEILF:
8815     case BUILT_IN_CEILL:
8816       return fold_builtin_ceil (fndecl, arglist);
8817
8818     case BUILT_IN_TRUNC:
8819     case BUILT_IN_TRUNCF:
8820     case BUILT_IN_TRUNCL:
8821       return fold_builtin_trunc (fndecl, arglist);
8822
8823     case BUILT_IN_ROUND:
8824     case BUILT_IN_ROUNDF:
8825     case BUILT_IN_ROUNDL:
8826       return fold_builtin_round (fndecl, arglist);
8827
8828     case BUILT_IN_NEARBYINT:
8829     case BUILT_IN_NEARBYINTF:
8830     case BUILT_IN_NEARBYINTL:
8831     case BUILT_IN_RINT:
8832     case BUILT_IN_RINTF:
8833     case BUILT_IN_RINTL:
8834       return fold_trunc_transparent_mathfn (fndecl, arglist);
8835
8836     case BUILT_IN_LCEIL:
8837     case BUILT_IN_LCEILF:
8838     case BUILT_IN_LCEILL:
8839     case BUILT_IN_LLCEIL:
8840     case BUILT_IN_LLCEILF:
8841     case BUILT_IN_LLCEILL:
8842     case BUILT_IN_LFLOOR:
8843     case BUILT_IN_LFLOORF:
8844     case BUILT_IN_LFLOORL:
8845     case BUILT_IN_LLFLOOR:
8846     case BUILT_IN_LLFLOORF:
8847     case BUILT_IN_LLFLOORL:
8848     case BUILT_IN_LROUND:
8849     case BUILT_IN_LROUNDF:
8850     case BUILT_IN_LROUNDL:
8851     case BUILT_IN_LLROUND:
8852     case BUILT_IN_LLROUNDF:
8853     case BUILT_IN_LLROUNDL:
8854       return fold_builtin_int_roundingfn (fndecl, arglist);
8855
8856     case BUILT_IN_LRINT:
8857     case BUILT_IN_LRINTF:
8858     case BUILT_IN_LRINTL:
8859     case BUILT_IN_LLRINT:
8860     case BUILT_IN_LLRINTF:
8861     case BUILT_IN_LLRINTL:
8862       return fold_fixed_mathfn (fndecl, arglist);
8863
8864     case BUILT_IN_FFS:
8865     case BUILT_IN_FFSL:
8866     case BUILT_IN_FFSLL:
8867     case BUILT_IN_CLZ:
8868     case BUILT_IN_CLZL:
8869     case BUILT_IN_CLZLL:
8870     case BUILT_IN_CTZ:
8871     case BUILT_IN_CTZL:
8872     case BUILT_IN_CTZLL:
8873     case BUILT_IN_POPCOUNT:
8874     case BUILT_IN_POPCOUNTL:
8875     case BUILT_IN_POPCOUNTLL:
8876     case BUILT_IN_PARITY:
8877     case BUILT_IN_PARITYL:
8878     case BUILT_IN_PARITYLL:
8879       return fold_builtin_bitop (fndecl, arglist);
8880
8881     case BUILT_IN_MEMCPY:
8882       return fold_builtin_memcpy (fndecl, arglist);
8883
8884     case BUILT_IN_MEMPCPY:
8885       return fold_builtin_mempcpy (arglist, type, /*endp=*/1);
8886
8887     case BUILT_IN_MEMMOVE:
8888       return fold_builtin_memmove (arglist, type);
8889
8890     case BUILT_IN_SIGNBIT:
8891     case BUILT_IN_SIGNBITF:
8892     case BUILT_IN_SIGNBITL:
8893       return fold_builtin_signbit (fndecl, arglist);
8894
8895     case BUILT_IN_ISASCII:
8896       return fold_builtin_isascii (arglist);
8897
8898     case BUILT_IN_TOASCII:
8899       return fold_builtin_toascii (arglist);
8900
8901     case BUILT_IN_ISDIGIT:
8902       return fold_builtin_isdigit (arglist);
8903
8904     case BUILT_IN_COPYSIGN:
8905     case BUILT_IN_COPYSIGNF:
8906     case BUILT_IN_COPYSIGNL:
8907       return fold_builtin_copysign (fndecl, arglist, type);
8908
8909     case BUILT_IN_FINITE:
8910     case BUILT_IN_FINITEF:
8911     case BUILT_IN_FINITEL:
8912       return fold_builtin_classify (fndecl, arglist, BUILT_IN_FINITE);
8913
8914     case BUILT_IN_ISINF:
8915     case BUILT_IN_ISINFF:
8916     case BUILT_IN_ISINFL:
8917       return fold_builtin_classify (fndecl, arglist, BUILT_IN_ISINF);
8918
8919     case BUILT_IN_ISNAN:
8920     case BUILT_IN_ISNANF:
8921     case BUILT_IN_ISNANL:
8922       return fold_builtin_classify (fndecl, arglist, BUILT_IN_ISNAN);
8923
8924     case BUILT_IN_ISGREATER:
8925       return fold_builtin_unordered_cmp (fndecl, arglist, UNLE_EXPR, LE_EXPR);
8926     case BUILT_IN_ISGREATEREQUAL:
8927       return fold_builtin_unordered_cmp (fndecl, arglist, UNLT_EXPR, LT_EXPR);
8928     case BUILT_IN_ISLESS:
8929       return fold_builtin_unordered_cmp (fndecl, arglist, UNGE_EXPR, GE_EXPR);
8930     case BUILT_IN_ISLESSEQUAL:
8931       return fold_builtin_unordered_cmp (fndecl, arglist, UNGT_EXPR, GT_EXPR);
8932     case BUILT_IN_ISLESSGREATER:
8933       return fold_builtin_unordered_cmp (fndecl, arglist, UNEQ_EXPR, EQ_EXPR);
8934     case BUILT_IN_ISUNORDERED:
8935       return fold_builtin_unordered_cmp (fndecl, arglist, UNORDERED_EXPR,
8936                                          NOP_EXPR);
8937
8938       /* We do the folding for va_start in the expander.  */
8939     case BUILT_IN_VA_START:
8940       break;
8941
8942     case BUILT_IN_OBJECT_SIZE:
8943       return fold_builtin_object_size (arglist);
8944     case BUILT_IN_MEMCPY_CHK:
8945     case BUILT_IN_MEMPCPY_CHK:
8946     case BUILT_IN_MEMMOVE_CHK:
8947     case BUILT_IN_MEMSET_CHK:
8948       return fold_builtin_memory_chk (fndecl, arglist, NULL_TREE, ignore,
8949                                       DECL_FUNCTION_CODE (fndecl));
8950     case BUILT_IN_STRCPY_CHK:
8951     case BUILT_IN_STPCPY_CHK:
8952       return fold_builtin_stxcpy_chk (fndecl, arglist, NULL_TREE, ignore,
8953                                       DECL_FUNCTION_CODE (fndecl));
8954     case BUILT_IN_STRNCPY_CHK:
8955       return fold_builtin_strncpy_chk (arglist, NULL_TREE);
8956     case BUILT_IN_STRCAT_CHK:
8957       return fold_builtin_strcat_chk (fndecl, arglist);
8958     case BUILT_IN_STRNCAT_CHK:
8959       return fold_builtin_strncat_chk (fndecl, arglist);
8960     case BUILT_IN_SPRINTF_CHK:
8961     case BUILT_IN_VSPRINTF_CHK:
8962       return fold_builtin_sprintf_chk (arglist, DECL_FUNCTION_CODE (fndecl));
8963     case BUILT_IN_SNPRINTF_CHK:
8964     case BUILT_IN_VSNPRINTF_CHK:
8965       return fold_builtin_snprintf_chk (arglist, NULL_TREE,
8966                                         DECL_FUNCTION_CODE (fndecl));
8967
8968     case BUILT_IN_PRINTF:
8969     case BUILT_IN_PRINTF_UNLOCKED:
8970     case BUILT_IN_VPRINTF:
8971     case BUILT_IN_PRINTF_CHK:
8972     case BUILT_IN_VPRINTF_CHK:
8973       return fold_builtin_printf (fndecl, arglist, ignore,
8974                                   DECL_FUNCTION_CODE (fndecl));
8975
8976     case BUILT_IN_FPRINTF:
8977     case BUILT_IN_FPRINTF_UNLOCKED:
8978     case BUILT_IN_VFPRINTF:
8979     case BUILT_IN_FPRINTF_CHK:
8980     case BUILT_IN_VFPRINTF_CHK:
8981       return fold_builtin_fprintf (fndecl, arglist, ignore,
8982                                    DECL_FUNCTION_CODE (fndecl));
8983
8984     default:
8985       break;
8986     }
8987
8988   return 0;
8989 }
8990
8991 /* A wrapper function for builtin folding that prevents warnings for
8992    "statement without effect" and the like, caused by removing the
8993    call node earlier than the warning is generated.  */
8994
8995 tree
8996 fold_builtin (tree fndecl, tree arglist, bool ignore)
8997 {
8998   tree exp = fold_builtin_1 (fndecl, arglist, ignore);
8999   if (exp)
9000     {
9001       exp = build1 (NOP_EXPR, TREE_TYPE (exp), exp);
9002       TREE_NO_WARNING (exp) = 1;
9003     }
9004
9005   return exp;
9006 }
9007
9008 /* Conveniently construct a function call expression.  */
9009
9010 tree
9011 build_function_call_expr (tree fn, tree arglist)
9012 {
9013   tree call_expr;
9014
9015   call_expr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (fn)), fn);
9016   return fold_build3 (CALL_EXPR, TREE_TYPE (TREE_TYPE (fn)),
9017                       call_expr, arglist, NULL_TREE);
9018 }
9019
9020 /* This function validates the types of a function call argument list
9021    represented as a tree chain of parameters against a specified list
9022    of tree_codes.  If the last specifier is a 0, that represents an
9023    ellipses, otherwise the last specifier must be a VOID_TYPE.  */
9024
9025 static int
9026 validate_arglist (tree arglist, ...)
9027 {
9028   enum tree_code code;
9029   int res = 0;
9030   va_list ap;
9031
9032   va_start (ap, arglist);
9033
9034   do
9035     {
9036       code = va_arg (ap, enum tree_code);
9037       switch (code)
9038         {
9039         case 0:
9040           /* This signifies an ellipses, any further arguments are all ok.  */
9041           res = 1;
9042           goto end;
9043         case VOID_TYPE:
9044           /* This signifies an endlink, if no arguments remain, return
9045              true, otherwise return false.  */
9046           res = arglist == 0;
9047           goto end;
9048         default:
9049           /* If no parameters remain or the parameter's code does not
9050              match the specified code, return false.  Otherwise continue
9051              checking any remaining arguments.  */
9052           if (arglist == 0)
9053             goto end;
9054           if (code == POINTER_TYPE)
9055             {
9056               if (! POINTER_TYPE_P (TREE_TYPE (TREE_VALUE (arglist))))
9057                 goto end;
9058             }
9059           else if (code != TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))))
9060             goto end;
9061           break;
9062         }
9063       arglist = TREE_CHAIN (arglist);
9064     }
9065   while (1);
9066
9067   /* We need gotos here since we can only have one VA_CLOSE in a
9068      function.  */
9069  end: ;
9070   va_end (ap);
9071
9072   return res;
9073 }
9074
9075 /* Default target-specific builtin expander that does nothing.  */
9076
9077 rtx
9078 default_expand_builtin (tree exp ATTRIBUTE_UNUSED,
9079                         rtx target ATTRIBUTE_UNUSED,
9080                         rtx subtarget ATTRIBUTE_UNUSED,
9081                         enum machine_mode mode ATTRIBUTE_UNUSED,
9082                         int ignore ATTRIBUTE_UNUSED)
9083 {
9084   return NULL_RTX;
9085 }
9086
9087 /* Returns true is EXP represents data that would potentially reside
9088    in a readonly section.  */
9089
9090 static bool
9091 readonly_data_expr (tree exp)
9092 {
9093   STRIP_NOPS (exp);
9094
9095   if (TREE_CODE (exp) != ADDR_EXPR)
9096     return false;
9097
9098   exp = get_base_address (TREE_OPERAND (exp, 0));
9099   if (!exp)
9100     return false;
9101
9102   /* Make sure we call decl_readonly_section only for trees it
9103      can handle (since it returns true for everything it doesn't
9104      understand).  */
9105   if (TREE_CODE (exp) == STRING_CST
9106       || TREE_CODE (exp) == CONSTRUCTOR
9107       || (TREE_CODE (exp) == VAR_DECL && TREE_STATIC (exp)))
9108     return decl_readonly_section (exp, 0);
9109   else
9110     return false;
9111 }
9112
9113 /* Simplify a call to the strstr builtin.
9114
9115    Return 0 if no simplification was possible, otherwise return the
9116    simplified form of the call as a tree.
9117
9118    The simplified form may be a constant or other expression which
9119    computes the same value, but in a more efficient manner (including
9120    calls to other builtin functions).
9121
9122    The call may contain arguments which need to be evaluated, but
9123    which are not useful to determine the result of the call.  In
9124    this case we return a chain of COMPOUND_EXPRs.  The LHS of each
9125    COMPOUND_EXPR will be an argument which must be evaluated.
9126    COMPOUND_EXPRs are chained through their RHS.  The RHS of the last
9127    COMPOUND_EXPR in the chain will contain the tree for the simplified
9128    form of the builtin function call.  */
9129
9130 static tree
9131 fold_builtin_strstr (tree arglist, tree type)
9132 {
9133   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
9134     return 0;
9135   else
9136     {
9137       tree s1 = TREE_VALUE (arglist), s2 = TREE_VALUE (TREE_CHAIN (arglist));
9138       tree fn;
9139       const char *p1, *p2;
9140
9141       p2 = c_getstr (s2);
9142       if (p2 == NULL)
9143         return 0;
9144
9145       p1 = c_getstr (s1);
9146       if (p1 != NULL)
9147         {
9148           const char *r = strstr (p1, p2);
9149           tree tem;
9150
9151           if (r == NULL)
9152             return build_int_cst (TREE_TYPE (s1), 0);
9153
9154           /* Return an offset into the constant string argument.  */
9155           tem = fold_build2 (PLUS_EXPR, TREE_TYPE (s1),
9156                              s1, build_int_cst (TREE_TYPE (s1), r - p1));
9157           return fold_convert (type, tem);
9158         }
9159
9160       if (p2[0] == '\0')
9161         return s1;
9162
9163       if (p2[1] != '\0')
9164         return 0;
9165
9166       fn = implicit_built_in_decls[BUILT_IN_STRCHR];
9167       if (!fn)
9168         return 0;
9169
9170       /* New argument list transforming strstr(s1, s2) to
9171          strchr(s1, s2[0]).  */
9172       arglist = build_tree_list (NULL_TREE,
9173                                  build_int_cst (NULL_TREE, p2[0]));
9174       arglist = tree_cons (NULL_TREE, s1, arglist);
9175       return build_function_call_expr (fn, arglist);
9176     }
9177 }
9178
9179 /* Simplify a call to the strchr builtin.
9180
9181    Return 0 if no simplification was possible, otherwise return the
9182    simplified form of the call as a tree.
9183
9184    The simplified form may be a constant or other expression which
9185    computes the same value, but in a more efficient manner (including
9186    calls to other builtin functions).
9187
9188    The call may contain arguments which need to be evaluated, but
9189    which are not useful to determine the result of the call.  In
9190    this case we return a chain of COMPOUND_EXPRs.  The LHS of each
9191    COMPOUND_EXPR will be an argument which must be evaluated.
9192    COMPOUND_EXPRs are chained through their RHS.  The RHS of the last
9193    COMPOUND_EXPR in the chain will contain the tree for the simplified
9194    form of the builtin function call.  */
9195
9196 static tree
9197 fold_builtin_strchr (tree arglist, tree type)
9198 {
9199   if (!validate_arglist (arglist, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
9200     return 0;
9201   else
9202     {
9203       tree s1 = TREE_VALUE (arglist), s2 = TREE_VALUE (TREE_CHAIN (arglist));
9204       const char *p1;
9205
9206       if (TREE_CODE (s2) != INTEGER_CST)
9207         return 0;
9208
9209       p1 = c_getstr (s1);
9210       if (p1 != NULL)
9211         {
9212           char c;
9213           const char *r;
9214           tree tem;
9215
9216           if (target_char_cast (s2, &c))
9217             return 0;
9218
9219           r = strchr (p1, c);
9220
9221           if (r == NULL)
9222             return build_int_cst (TREE_TYPE (s1), 0);
9223
9224           /* Return an offset into the constant string argument.  */
9225           tem = fold_build2 (PLUS_EXPR, TREE_TYPE (s1),
9226                              s1, build_int_cst (TREE_TYPE (s1), r - p1));
9227           return fold_convert (type, tem);
9228         }
9229       return 0;
9230     }
9231 }
9232
9233 /* Simplify a call to the strrchr builtin.
9234
9235    Return 0 if no simplification was possible, otherwise return the
9236    simplified form of the call as a tree.
9237
9238    The simplified form may be a constant or other expression which
9239    computes the same value, but in a more efficient manner (including
9240    calls to other builtin functions).
9241
9242    The call may contain arguments which need to be evaluated, but
9243    which are not useful to determine the result of the call.  In
9244    this case we return a chain of COMPOUND_EXPRs.  The LHS of each
9245    COMPOUND_EXPR will be an argument which must be evaluated.
9246    COMPOUND_EXPRs are chained through their RHS.  The RHS of the last
9247    COMPOUND_EXPR in the chain will contain the tree for the simplified
9248    form of the builtin function call.  */
9249
9250 static tree
9251 fold_builtin_strrchr (tree arglist, tree type)
9252 {
9253   if (!validate_arglist (arglist, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
9254     return 0;
9255   else
9256     {
9257       tree s1 = TREE_VALUE (arglist), s2 = TREE_VALUE (TREE_CHAIN (arglist));
9258       tree fn;
9259       const char *p1;
9260
9261       if (TREE_CODE (s2) != INTEGER_CST)
9262         return 0;
9263
9264       p1 = c_getstr (s1);
9265       if (p1 != NULL)
9266         {
9267           char c;
9268           const char *r;
9269           tree tem;
9270
9271           if (target_char_cast (s2, &c))
9272             return 0;
9273
9274           r = strrchr (p1, c);
9275
9276           if (r == NULL)
9277             return build_int_cst (TREE_TYPE (s1), 0);
9278
9279           /* Return an offset into the constant string argument.  */
9280           tem = fold_build2 (PLUS_EXPR, TREE_TYPE (s1),
9281                              s1, build_int_cst (TREE_TYPE (s1), r - p1));
9282           return fold_convert (type, tem);
9283         }
9284
9285       if (! integer_zerop (s2))
9286         return 0;
9287
9288       fn = implicit_built_in_decls[BUILT_IN_STRCHR];
9289       if (!fn)
9290         return 0;
9291
9292       /* Transform strrchr(s1, '\0') to strchr(s1, '\0').  */
9293       return build_function_call_expr (fn, arglist);
9294     }
9295 }
9296
9297 /* Simplify a call to the strpbrk builtin.
9298
9299    Return 0 if no simplification was possible, otherwise return the
9300    simplified form of the call as a tree.
9301
9302    The simplified form may be a constant or other expression which
9303    computes the same value, but in a more efficient manner (including
9304    calls to other builtin functions).
9305
9306    The call may contain arguments which need to be evaluated, but
9307    which are not useful to determine the result of the call.  In
9308    this case we return a chain of COMPOUND_EXPRs.  The LHS of each
9309    COMPOUND_EXPR will be an argument which must be evaluated.
9310    COMPOUND_EXPRs are chained through their RHS.  The RHS of the last
9311    COMPOUND_EXPR in the chain will contain the tree for the simplified
9312    form of the builtin function call.  */
9313
9314 static tree
9315 fold_builtin_strpbrk (tree arglist, tree type)
9316 {
9317   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
9318     return 0;
9319   else
9320     {
9321       tree s1 = TREE_VALUE (arglist), s2 = TREE_VALUE (TREE_CHAIN (arglist));
9322       tree fn;
9323       const char *p1, *p2;
9324
9325       p2 = c_getstr (s2);
9326       if (p2 == NULL)
9327         return 0;
9328
9329       p1 = c_getstr (s1);
9330       if (p1 != NULL)
9331         {
9332           const char *r = strpbrk (p1, p2);
9333           tree tem;
9334
9335           if (r == NULL)
9336             return build_int_cst (TREE_TYPE (s1), 0);
9337
9338           /* Return an offset into the constant string argument.  */
9339           tem = fold_build2 (PLUS_EXPR, TREE_TYPE (s1),
9340                              s1, build_int_cst (TREE_TYPE (s1), r - p1));
9341           return fold_convert (type, tem);
9342         }
9343
9344       if (p2[0] == '\0')
9345         /* strpbrk(x, "") == NULL.
9346            Evaluate and ignore s1 in case it had side-effects.  */
9347         return omit_one_operand (TREE_TYPE (s1), integer_zero_node, s1);
9348
9349       if (p2[1] != '\0')
9350         return 0;  /* Really call strpbrk.  */
9351
9352       fn = implicit_built_in_decls[BUILT_IN_STRCHR];
9353       if (!fn)
9354         return 0;
9355
9356       /* New argument list transforming strpbrk(s1, s2) to
9357          strchr(s1, s2[0]).  */
9358       arglist = build_tree_list (NULL_TREE,
9359                                  build_int_cst (NULL_TREE, p2[0]));
9360       arglist = tree_cons (NULL_TREE, s1, arglist);
9361       return build_function_call_expr (fn, arglist);
9362     }
9363 }
9364
9365 /* Simplify a call to the strcat builtin.
9366
9367    Return 0 if no simplification was possible, otherwise return the
9368    simplified form of the call as a tree.
9369
9370    The simplified form may be a constant or other expression which
9371    computes the same value, but in a more efficient manner (including
9372    calls to other builtin functions).
9373
9374    The call may contain arguments which need to be evaluated, but
9375    which are not useful to determine the result of the call.  In
9376    this case we return a chain of COMPOUND_EXPRs.  The LHS of each
9377    COMPOUND_EXPR will be an argument which must be evaluated.
9378    COMPOUND_EXPRs are chained through their RHS.  The RHS of the last
9379    COMPOUND_EXPR in the chain will contain the tree for the simplified
9380    form of the builtin function call.  */
9381
9382 static tree
9383 fold_builtin_strcat (tree arglist)
9384 {
9385   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
9386     return 0;
9387   else
9388     {
9389       tree dst = TREE_VALUE (arglist),
9390         src = TREE_VALUE (TREE_CHAIN (arglist));
9391       const char *p = c_getstr (src);
9392
9393       /* If the string length is zero, return the dst parameter.  */
9394       if (p && *p == '\0')
9395         return dst;
9396
9397       return 0;
9398     }
9399 }
9400
9401 /* Simplify a call to the strncat builtin.
9402
9403    Return 0 if no simplification was possible, otherwise return the
9404    simplified form of the call as a tree.
9405
9406    The simplified form may be a constant or other expression which
9407    computes the same value, but in a more efficient manner (including
9408    calls to other builtin functions).
9409
9410    The call may contain arguments which need to be evaluated, but
9411    which are not useful to determine the result of the call.  In
9412    this case we return a chain of COMPOUND_EXPRs.  The LHS of each
9413    COMPOUND_EXPR will be an argument which must be evaluated.
9414    COMPOUND_EXPRs are chained through their RHS.  The RHS of the last
9415    COMPOUND_EXPR in the chain will contain the tree for the simplified
9416    form of the builtin function call.  */
9417
9418 static tree
9419 fold_builtin_strncat (tree arglist)
9420 {
9421   if (!validate_arglist (arglist,
9422                          POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
9423     return 0;
9424   else
9425     {
9426       tree dst = TREE_VALUE (arglist);
9427       tree src = TREE_VALUE (TREE_CHAIN (arglist));
9428       tree len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
9429       const char *p = c_getstr (src);
9430
9431       /* If the requested length is zero, or the src parameter string
9432          length is zero, return the dst parameter.  */
9433       if (integer_zerop (len) || (p && *p == '\0'))
9434         return omit_two_operands (TREE_TYPE (dst), dst, src, len);
9435
9436       /* If the requested len is greater than or equal to the string
9437          length, call strcat.  */
9438       if (TREE_CODE (len) == INTEGER_CST && p
9439           && compare_tree_int (len, strlen (p)) >= 0)
9440         {
9441           tree newarglist
9442             = tree_cons (NULL_TREE, dst, build_tree_list (NULL_TREE, src));
9443           tree fn = implicit_built_in_decls[BUILT_IN_STRCAT];
9444
9445           /* If the replacement _DECL isn't initialized, don't do the
9446              transformation.  */
9447           if (!fn)
9448             return 0;
9449
9450           return build_function_call_expr (fn, newarglist);
9451         }
9452       return 0;
9453     }
9454 }
9455
9456 /* Simplify a call to the strspn builtin.
9457
9458    Return 0 if no simplification was possible, otherwise return the
9459    simplified form of the call as a tree.
9460
9461    The simplified form may be a constant or other expression which
9462    computes the same value, but in a more efficient manner (including
9463    calls to other builtin functions).
9464
9465    The call may contain arguments which need to be evaluated, but
9466    which are not useful to determine the result of the call.  In
9467    this case we return a chain of COMPOUND_EXPRs.  The LHS of each
9468    COMPOUND_EXPR will be an argument which must be evaluated.
9469    COMPOUND_EXPRs are chained through their RHS.  The RHS of the last
9470    COMPOUND_EXPR in the chain will contain the tree for the simplified
9471    form of the builtin function call.  */
9472
9473 static tree
9474 fold_builtin_strspn (tree arglist)
9475 {
9476   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
9477     return 0;
9478   else
9479     {
9480       tree s1 = TREE_VALUE (arglist), s2 = TREE_VALUE (TREE_CHAIN (arglist));
9481       const char *p1 = c_getstr (s1), *p2 = c_getstr (s2);
9482
9483       /* If both arguments are constants, evaluate at compile-time.  */
9484       if (p1 && p2)
9485         {
9486           const size_t r = strspn (p1, p2);
9487           return size_int (r);
9488         }
9489
9490       /* If either argument is "", return 0.  */
9491       if ((p1 && *p1 == '\0') || (p2 && *p2 == '\0'))
9492         /* Evaluate and ignore both arguments in case either one has
9493            side-effects.  */
9494         return omit_two_operands (integer_type_node, integer_zero_node,
9495                                   s1, s2);
9496       return 0;
9497     }
9498 }
9499
9500 /* Simplify a call to the strcspn builtin.
9501
9502    Return 0 if no simplification was possible, otherwise return the
9503    simplified form of the call as a tree.
9504
9505    The simplified form may be a constant or other expression which
9506    computes the same value, but in a more efficient manner (including
9507    calls to other builtin functions).
9508
9509    The call may contain arguments which need to be evaluated, but
9510    which are not useful to determine the result of the call.  In
9511    this case we return a chain of COMPOUND_EXPRs.  The LHS of each
9512    COMPOUND_EXPR will be an argument which must be evaluated.
9513    COMPOUND_EXPRs are chained through their RHS.  The RHS of the last
9514    COMPOUND_EXPR in the chain will contain the tree for the simplified
9515    form of the builtin function call.  */
9516
9517 static tree
9518 fold_builtin_strcspn (tree arglist)
9519 {
9520   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
9521     return 0;
9522   else
9523     {
9524       tree s1 = TREE_VALUE (arglist), s2 = TREE_VALUE (TREE_CHAIN (arglist));
9525       const char *p1 = c_getstr (s1), *p2 = c_getstr (s2);
9526
9527       /* If both arguments are constants, evaluate at compile-time.  */
9528       if (p1 && p2)
9529         {
9530           const size_t r = strcspn (p1, p2);
9531           return size_int (r);
9532         }
9533
9534       /* If the first argument is "", return 0.  */
9535       if (p1 && *p1 == '\0')
9536         {
9537           /* Evaluate and ignore argument s2 in case it has
9538              side-effects.  */
9539           return omit_one_operand (integer_type_node,
9540                                    integer_zero_node, s2);
9541         }
9542
9543       /* If the second argument is "", return __builtin_strlen(s1).  */
9544       if (p2 && *p2 == '\0')
9545         {
9546           tree newarglist = build_tree_list (NULL_TREE, s1),
9547             fn = implicit_built_in_decls[BUILT_IN_STRLEN];
9548
9549           /* If the replacement _DECL isn't initialized, don't do the
9550              transformation.  */
9551           if (!fn)
9552             return 0;
9553
9554           return build_function_call_expr (fn, newarglist);
9555         }
9556       return 0;
9557     }
9558 }
9559
9560 /* Fold a call to the fputs builtin.  IGNORE is true if the value returned
9561    by the builtin will be ignored.  UNLOCKED is true is true if this
9562    actually a call to fputs_unlocked.  If LEN in non-NULL, it represents
9563    the known length of the string.  Return NULL_TREE if no simplification
9564    was possible.  */
9565
9566 tree
9567 fold_builtin_fputs (tree arglist, bool ignore, bool unlocked, tree len)
9568 {
9569   tree fn;
9570   tree fn_fputc = unlocked ? implicit_built_in_decls[BUILT_IN_FPUTC_UNLOCKED]
9571     : implicit_built_in_decls[BUILT_IN_FPUTC];
9572   tree fn_fwrite = unlocked ? implicit_built_in_decls[BUILT_IN_FWRITE_UNLOCKED]
9573     : implicit_built_in_decls[BUILT_IN_FWRITE];
9574
9575   /* If the return value is used, or the replacement _DECL isn't
9576      initialized, don't do the transformation.  */
9577   if (!ignore || !fn_fputc || !fn_fwrite)
9578     return 0;
9579
9580   /* Verify the arguments in the original call.  */
9581   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE))
9582     return 0;
9583
9584   if (! len)
9585     len = c_strlen (TREE_VALUE (arglist), 0);
9586
9587   /* Get the length of the string passed to fputs.  If the length
9588      can't be determined, punt.  */
9589   if (!len
9590       || TREE_CODE (len) != INTEGER_CST)
9591     return 0;
9592
9593   switch (compare_tree_int (len, 1))
9594     {
9595     case -1: /* length is 0, delete the call entirely .  */
9596       return omit_one_operand (integer_type_node, integer_zero_node,
9597                                TREE_VALUE (TREE_CHAIN (arglist)));
9598
9599     case 0: /* length is 1, call fputc.  */
9600       {
9601         const char *p = c_getstr (TREE_VALUE (arglist));
9602
9603         if (p != NULL)
9604           {
9605             /* New argument list transforming fputs(string, stream) to
9606                fputc(string[0], stream).  */
9607             arglist = build_tree_list (NULL_TREE,
9608                                        TREE_VALUE (TREE_CHAIN (arglist)));
9609             arglist = tree_cons (NULL_TREE,
9610                                  build_int_cst (NULL_TREE, p[0]),
9611                                  arglist);
9612             fn = fn_fputc;
9613             break;
9614           }
9615       }
9616       /* FALLTHROUGH */
9617     case 1: /* length is greater than 1, call fwrite.  */
9618       {
9619         tree string_arg;
9620
9621         /* If optimizing for size keep fputs.  */
9622         if (optimize_size)
9623           return 0;
9624         string_arg = TREE_VALUE (arglist);
9625         /* New argument list transforming fputs(string, stream) to
9626            fwrite(string, 1, len, stream).  */
9627         arglist = build_tree_list (NULL_TREE,
9628                                    TREE_VALUE (TREE_CHAIN (arglist)));
9629         arglist = tree_cons (NULL_TREE, len, arglist);
9630         arglist = tree_cons (NULL_TREE, size_one_node, arglist);
9631         arglist = tree_cons (NULL_TREE, string_arg, arglist);
9632         fn = fn_fwrite;
9633         break;
9634       }
9635     default:
9636       gcc_unreachable ();
9637     }
9638
9639   /* These optimizations are only performed when the result is ignored,
9640      hence there's no need to cast the result to integer_type_node.  */
9641   return build_function_call_expr (fn, arglist);
9642 }
9643
9644 /* Fold the new_arg's arguments (ARGLIST). Returns true if there was an error
9645    produced.  False otherwise.  This is done so that we don't output the error
9646    or warning twice or three times.  */
9647 bool
9648 fold_builtin_next_arg (tree arglist)
9649 {
9650   tree fntype = TREE_TYPE (current_function_decl);
9651
9652   if (TYPE_ARG_TYPES (fntype) == 0
9653       || (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
9654           == void_type_node))
9655     {
9656       error ("%<va_start%> used in function with fixed args");
9657       return true;
9658     }
9659   else if (!arglist)
9660     {
9661       /* Evidently an out of date version of <stdarg.h>; can't validate
9662          va_start's second argument, but can still work as intended.  */
9663       warning (0, "%<__builtin_next_arg%> called without an argument");
9664       return true;
9665     }
9666   /* We use __builtin_va_start (ap, 0, 0) or __builtin_next_arg (0, 0)
9667      when we checked the arguments and if needed issued a warning.  */
9668   else if (!TREE_CHAIN (arglist)
9669            || !integer_zerop (TREE_VALUE (arglist))
9670            || !integer_zerop (TREE_VALUE (TREE_CHAIN (arglist)))
9671            || TREE_CHAIN (TREE_CHAIN (arglist)))
9672     {
9673       tree last_parm = tree_last (DECL_ARGUMENTS (current_function_decl));
9674       tree arg = TREE_VALUE (arglist);
9675
9676       if (TREE_CHAIN (arglist))
9677         {
9678           error ("%<va_start%> used with too many arguments");
9679           return true;
9680         }
9681
9682       /* Strip off all nops for the sake of the comparison.  This
9683          is not quite the same as STRIP_NOPS.  It does more.
9684          We must also strip off INDIRECT_EXPR for C++ reference
9685          parameters.  */
9686       while (TREE_CODE (arg) == NOP_EXPR
9687              || TREE_CODE (arg) == CONVERT_EXPR
9688              || TREE_CODE (arg) == NON_LVALUE_EXPR
9689              || TREE_CODE (arg) == INDIRECT_REF)
9690         arg = TREE_OPERAND (arg, 0);
9691       if (arg != last_parm)
9692         {
9693           /* FIXME: Sometimes with the tree optimizers we can get the
9694              not the last argument even though the user used the last
9695              argument.  We just warn and set the arg to be the last
9696              argument so that we will get wrong-code because of
9697              it.  */
9698           warning (0, "second parameter of %<va_start%> not last named argument");
9699         }
9700       /* We want to verify the second parameter just once before the tree
9701          optimizers are run and then avoid keeping it in the tree,
9702          as otherwise we could warn even for correct code like:
9703          void foo (int i, ...)
9704          { va_list ap; i++; va_start (ap, i); va_end (ap); }  */
9705       TREE_VALUE (arglist) = integer_zero_node;
9706       TREE_CHAIN (arglist) = build_tree_list (NULL, integer_zero_node);
9707     }
9708   return false;
9709 }
9710
9711
9712 /* Simplify a call to the sprintf builtin.
9713
9714    Return 0 if no simplification was possible, otherwise return the
9715    simplified form of the call as a tree.  If IGNORED is true, it means that
9716    the caller does not use the returned value of the function.  */
9717
9718 static tree
9719 fold_builtin_sprintf (tree arglist, int ignored)
9720 {
9721   tree call, retval, dest, fmt;
9722   const char *fmt_str = NULL;
9723
9724   /* Verify the required arguments in the original call.  We deal with two
9725      types of sprintf() calls: 'sprintf (str, fmt)' and
9726      'sprintf (dest, "%s", orig)'.  */
9727   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, VOID_TYPE)
9728       && !validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, POINTER_TYPE,
9729                             VOID_TYPE))
9730     return NULL_TREE;
9731
9732   /* Get the destination string and the format specifier.  */
9733   dest = TREE_VALUE (arglist);
9734   fmt = TREE_VALUE (TREE_CHAIN (arglist));
9735
9736   /* Check whether the format is a literal string constant.  */
9737   fmt_str = c_getstr (fmt);
9738   if (fmt_str == NULL)
9739     return NULL_TREE;
9740
9741   call = NULL_TREE;
9742   retval = NULL_TREE;
9743
9744   /* If the format doesn't contain % args or %%, use strcpy.  */
9745   if (strchr (fmt_str, '%') == NULL)
9746     {
9747       tree fn = implicit_built_in_decls[BUILT_IN_STRCPY];
9748
9749       if (!fn)
9750         return NULL_TREE;
9751
9752       /* Convert sprintf (str, fmt) into strcpy (str, fmt) when
9753          'format' is known to contain no % formats.  */
9754       arglist = build_tree_list (NULL_TREE, fmt);
9755       arglist = tree_cons (NULL_TREE, dest, arglist);
9756       call = build_function_call_expr (fn, arglist);
9757       if (!ignored)
9758         retval = build_int_cst (NULL_TREE, strlen (fmt_str));
9759     }
9760
9761   /* If the format is "%s", use strcpy if the result isn't used.  */
9762   else if (fmt_str && strcmp (fmt_str, "%s") == 0)
9763     {
9764       tree fn, orig;
9765       fn = implicit_built_in_decls[BUILT_IN_STRCPY];
9766
9767       if (!fn)
9768         return NULL_TREE;
9769
9770       /* Convert sprintf (str1, "%s", str2) into strcpy (str1, str2).  */
9771       orig = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
9772       arglist = build_tree_list (NULL_TREE, orig);
9773       arglist = tree_cons (NULL_TREE, dest, arglist);
9774       if (!ignored)
9775         {
9776           retval = c_strlen (orig, 1);
9777           if (!retval || TREE_CODE (retval) != INTEGER_CST)
9778             return NULL_TREE;
9779         }
9780       call = build_function_call_expr (fn, arglist);
9781     }
9782
9783   if (call && retval)
9784     {
9785       retval = convert
9786         (TREE_TYPE (TREE_TYPE (implicit_built_in_decls[BUILT_IN_SPRINTF])),
9787          retval);
9788       return build2 (COMPOUND_EXPR, TREE_TYPE (retval), call, retval);
9789     }
9790   else
9791     return call;
9792 }
9793
9794 /* Expand a call to __builtin_object_size.  */
9795
9796 rtx
9797 expand_builtin_object_size (tree exp)
9798 {
9799   tree ost;
9800   int object_size_type;
9801   tree fndecl = get_callee_fndecl (exp);
9802   tree arglist = TREE_OPERAND (exp, 1);
9803   location_t locus = EXPR_LOCATION (exp);
9804
9805   if (!validate_arglist (arglist, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
9806     {
9807       error ("%Hfirst argument of %D must be a pointer, second integer constant",
9808              &locus, fndecl);
9809       expand_builtin_trap ();
9810       return const0_rtx;
9811     }
9812
9813   ost = TREE_VALUE (TREE_CHAIN (arglist));
9814   STRIP_NOPS (ost);
9815
9816   if (TREE_CODE (ost) != INTEGER_CST
9817       || tree_int_cst_sgn (ost) < 0
9818       || compare_tree_int (ost, 3) > 0)
9819     {
9820       error ("%Hlast argument of %D is not integer constant between 0 and 3",
9821              &locus, fndecl);
9822       expand_builtin_trap ();
9823       return const0_rtx;
9824     }
9825
9826   object_size_type = tree_low_cst (ost, 0);
9827
9828   return object_size_type < 2 ? constm1_rtx : const0_rtx;
9829 }
9830
9831 /* Expand EXP, a call to the __mem{cpy,pcpy,move,set}_chk builtin.
9832    FCODE is the BUILT_IN_* to use.
9833    Return 0 if we failed; the caller should emit a normal call,
9834    otherwise try to get the result in TARGET, if convenient (and in
9835    mode MODE if that's convenient).  */
9836
9837 static rtx
9838 expand_builtin_memory_chk (tree exp, rtx target, enum machine_mode mode,
9839                            enum built_in_function fcode)
9840 {
9841   tree arglist = TREE_OPERAND (exp, 1);
9842   tree dest, src, len, size;
9843
9844   if (!validate_arglist (arglist,
9845                          POINTER_TYPE,
9846                          fcode == BUILT_IN_MEMSET_CHK
9847                          ? INTEGER_TYPE : POINTER_TYPE,
9848                          INTEGER_TYPE, INTEGER_TYPE, VOID_TYPE))
9849     return 0;
9850
9851   dest = TREE_VALUE (arglist);
9852   src = TREE_VALUE (TREE_CHAIN (arglist));
9853   len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
9854   size = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (TREE_CHAIN (arglist))));
9855
9856   if (! host_integerp (size, 1))
9857     return 0;
9858
9859   if (host_integerp (len, 1) || integer_all_onesp (size))
9860     {
9861       tree fn;
9862
9863       if (! integer_all_onesp (size) && tree_int_cst_lt (size, len))
9864         {
9865           location_t locus = EXPR_LOCATION (exp);
9866           warning (0, "%Hcall to %D will always overflow destination buffer",
9867                    &locus, get_callee_fndecl (exp));
9868           return 0;
9869         }
9870
9871       arglist = build_tree_list (NULL_TREE, len);
9872       arglist = tree_cons (NULL_TREE, src, arglist);
9873       arglist = tree_cons (NULL_TREE, dest, arglist);
9874
9875       fn = NULL_TREE;
9876       /* If __builtin_mem{cpy,pcpy,move,set}_chk is used, assume
9877          mem{cpy,pcpy,move,set} is available.  */
9878       switch (fcode)
9879         {
9880         case BUILT_IN_MEMCPY_CHK:
9881           fn = built_in_decls[BUILT_IN_MEMCPY];
9882           break;
9883         case BUILT_IN_MEMPCPY_CHK:
9884           fn = built_in_decls[BUILT_IN_MEMPCPY];
9885           break;
9886         case BUILT_IN_MEMMOVE_CHK:
9887           fn = built_in_decls[BUILT_IN_MEMMOVE];
9888           break;
9889         case BUILT_IN_MEMSET_CHK:
9890           fn = built_in_decls[BUILT_IN_MEMSET];
9891           break;
9892         default:
9893           break;
9894         }
9895
9896       if (! fn)
9897         return 0;
9898
9899       fn = build_function_call_expr (fn, arglist);
9900       if (TREE_CODE (fn) == CALL_EXPR)
9901         CALL_EXPR_TAILCALL (fn) = CALL_EXPR_TAILCALL (exp);
9902       return expand_expr (fn, target, mode, EXPAND_NORMAL);
9903     }
9904   else if (fcode == BUILT_IN_MEMSET_CHK)
9905     return 0;
9906   else
9907     {
9908       unsigned int dest_align
9909         = get_pointer_alignment (dest, BIGGEST_ALIGNMENT);
9910
9911       /* If DEST is not a pointer type, call the normal function.  */
9912       if (dest_align == 0)
9913         return 0;
9914
9915       /* If SRC and DEST are the same (and not volatile), do nothing.  */
9916       if (operand_equal_p (src, dest, 0))
9917         {
9918           tree expr;
9919
9920           if (fcode != BUILT_IN_MEMPCPY_CHK)
9921             {
9922               /* Evaluate and ignore LEN in case it has side-effects.  */
9923               expand_expr (len, const0_rtx, VOIDmode, EXPAND_NORMAL);
9924               return expand_expr (dest, target, mode, EXPAND_NORMAL);
9925             }
9926
9927           len = fold_convert (TREE_TYPE (dest), len);
9928           expr = fold_build2 (PLUS_EXPR, TREE_TYPE (dest), dest, len);
9929           return expand_expr (expr, target, mode, EXPAND_NORMAL);
9930         }
9931
9932       /* __memmove_chk special case.  */
9933       if (fcode == BUILT_IN_MEMMOVE_CHK)
9934         {
9935           unsigned int src_align
9936             = get_pointer_alignment (src, BIGGEST_ALIGNMENT);
9937
9938           if (src_align == 0)
9939             return 0;
9940
9941           /* If src is categorized for a readonly section we can use
9942              normal __memcpy_chk.  */
9943           if (readonly_data_expr (src))
9944             {
9945               tree fn = built_in_decls[BUILT_IN_MEMCPY_CHK];
9946               if (!fn)
9947                 return 0;
9948               fn = build_function_call_expr (fn, arglist);
9949               if (TREE_CODE (fn) == CALL_EXPR)
9950                 CALL_EXPR_TAILCALL (fn) = CALL_EXPR_TAILCALL (exp);
9951               return expand_expr (fn, target, mode, EXPAND_NORMAL);
9952             }
9953         }
9954       return 0;
9955     }
9956 }
9957
9958 /* Emit warning if a buffer overflow is detected at compile time.  */
9959
9960 static void
9961 maybe_emit_chk_warning (tree exp, enum built_in_function fcode)
9962 {
9963   int arg_mask, is_strlen = 0;
9964   tree arglist = TREE_OPERAND (exp, 1), a;
9965   tree len, size;
9966   location_t locus;
9967
9968   switch (fcode)
9969     {
9970     case BUILT_IN_STRCPY_CHK:
9971     case BUILT_IN_STPCPY_CHK:
9972     /* For __strcat_chk the warning will be emitted only if overflowing
9973        by at least strlen (dest) + 1 bytes.  */
9974     case BUILT_IN_STRCAT_CHK:
9975       arg_mask = 6;
9976       is_strlen = 1;
9977       break;
9978     case BUILT_IN_STRNCPY_CHK:
9979       arg_mask = 12;
9980       break;
9981     case BUILT_IN_SNPRINTF_CHK:
9982     case BUILT_IN_VSNPRINTF_CHK:
9983       arg_mask = 10;
9984       break;
9985     default:
9986       gcc_unreachable ();
9987     }
9988
9989   len = NULL_TREE;
9990   size = NULL_TREE;
9991   for (a = arglist; a && arg_mask; a = TREE_CHAIN (a), arg_mask >>= 1)
9992     if (arg_mask & 1)
9993       {
9994         if (len)
9995           size = a;
9996         else
9997           len = a;
9998       }
9999
10000   if (!len || !size)
10001     return;
10002
10003   len = TREE_VALUE (len);
10004   size = TREE_VALUE (size);
10005
10006   if (! host_integerp (size, 1) || integer_all_onesp (size))
10007     return;
10008
10009   if (is_strlen)
10010     {
10011       len = c_strlen (len, 1);
10012       if (! len || ! host_integerp (len, 1) || tree_int_cst_lt (len, size))
10013         return;
10014     }
10015   else if (! host_integerp (len, 1) || ! tree_int_cst_lt (size, len))
10016     return;
10017
10018   locus = EXPR_LOCATION (exp);
10019   warning (0, "%Hcall to %D will always overflow destination buffer",
10020            &locus, get_callee_fndecl (exp));
10021 }
10022
10023 /* Emit warning if a buffer overflow is detected at compile time
10024    in __sprintf_chk/__vsprintf_chk calls.  */
10025
10026 static void
10027 maybe_emit_sprintf_chk_warning (tree exp, enum built_in_function fcode)
10028 {
10029   tree arglist = TREE_OPERAND (exp, 1);
10030   tree dest, size, len, fmt, flag;
10031   const char *fmt_str;
10032
10033   /* Verify the required arguments in the original call.  */
10034   if (! arglist)
10035     return;
10036   dest = TREE_VALUE (arglist);
10037   arglist = TREE_CHAIN (arglist);
10038   if (! arglist)
10039     return;
10040   flag = TREE_VALUE (arglist);
10041   arglist = TREE_CHAIN (arglist);
10042   if (! arglist)
10043     return;
10044   size = TREE_VALUE (arglist);
10045   arglist = TREE_CHAIN (arglist);
10046   if (! arglist)
10047     return;
10048   fmt = TREE_VALUE (arglist);
10049   arglist = TREE_CHAIN (arglist);
10050
10051   if (! host_integerp (size, 1) || integer_all_onesp (size))
10052     return;
10053
10054   /* Check whether the format is a literal string constant.  */
10055   fmt_str = c_getstr (fmt);
10056   if (fmt_str == NULL)
10057     return;
10058
10059   /* If the format doesn't contain % args or %%, we know its size.  */
10060   if (strchr (fmt_str, '%') == 0)
10061     len = build_int_cstu (size_type_node, strlen (fmt_str));
10062   /* If the format is "%s" and first ... argument is a string literal,
10063      we know it too.  */
10064   else if (fcode == BUILT_IN_SPRINTF_CHK && strcmp (fmt_str, "%s") == 0)
10065     {
10066       tree arg;
10067
10068       if (! arglist)
10069         return;
10070       arg = TREE_VALUE (arglist);
10071       if (! POINTER_TYPE_P (TREE_TYPE (arg)))
10072         return;
10073
10074       len = c_strlen (arg, 1);
10075       if (!len || ! host_integerp (len, 1))
10076         return;
10077     }
10078   else
10079     return;
10080
10081   if (! tree_int_cst_lt (len, size))
10082     {
10083       location_t locus = EXPR_LOCATION (exp);
10084       warning (0, "%Hcall to %D will always overflow destination buffer",
10085                &locus, get_callee_fndecl (exp));
10086     }
10087 }
10088
10089 /* Fold a call to __builtin_object_size, if possible.  */
10090
10091 tree
10092 fold_builtin_object_size (tree arglist)
10093 {
10094   tree ptr, ost, ret = 0;
10095   int object_size_type;
10096
10097   if (!validate_arglist (arglist, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
10098     return 0;
10099
10100   ptr = TREE_VALUE (arglist);
10101   ost = TREE_VALUE (TREE_CHAIN (arglist));
10102   STRIP_NOPS (ost);
10103
10104   if (TREE_CODE (ost) != INTEGER_CST
10105       || tree_int_cst_sgn (ost) < 0
10106       || compare_tree_int (ost, 3) > 0)
10107     return 0;
10108
10109   object_size_type = tree_low_cst (ost, 0);
10110
10111   /* __builtin_object_size doesn't evaluate side-effects in its arguments;
10112      if there are any side-effects, it returns (size_t) -1 for types 0 and 1
10113      and (size_t) 0 for types 2 and 3.  */
10114   if (TREE_SIDE_EFFECTS (ptr))
10115     return fold_convert (size_type_node,
10116                          object_size_type < 2
10117                          ? integer_minus_one_node : integer_zero_node);
10118
10119   if (TREE_CODE (ptr) == ADDR_EXPR)
10120     ret = build_int_cstu (size_type_node,
10121                         compute_builtin_object_size (ptr, object_size_type));
10122
10123   else if (TREE_CODE (ptr) == SSA_NAME)
10124     {
10125       unsigned HOST_WIDE_INT bytes;
10126
10127       /* If object size is not known yet, delay folding until
10128        later.  Maybe subsequent passes will help determining
10129        it.  */
10130       bytes = compute_builtin_object_size (ptr, object_size_type);
10131       if (bytes != (unsigned HOST_WIDE_INT) (object_size_type < 2
10132                                              ? -1 : 0))
10133         ret = build_int_cstu (size_type_node, bytes);
10134     }
10135
10136   if (ret)
10137     {
10138       ret = force_fit_type (ret, -1, false, false);
10139       if (TREE_CONSTANT_OVERFLOW (ret))
10140         ret = 0;
10141     }
10142
10143   return ret;
10144 }
10145
10146 /* Fold a call to the __mem{cpy,pcpy,move,set}_chk builtin.
10147    IGNORE is true, if return value can be ignored.  FCODE is the BUILT_IN_*
10148    code of the builtin.  If MAXLEN is not NULL, it is maximum length
10149    passed as third argument.  */
10150
10151 tree
10152 fold_builtin_memory_chk (tree fndecl, tree arglist, tree maxlen, bool ignore,
10153                          enum built_in_function fcode)
10154 {
10155   tree dest, src, len, size, fn;
10156
10157   if (!validate_arglist (arglist,
10158                          POINTER_TYPE,
10159                          fcode == BUILT_IN_MEMSET_CHK
10160                          ? INTEGER_TYPE : POINTER_TYPE,
10161                          INTEGER_TYPE, INTEGER_TYPE, VOID_TYPE))
10162     return 0;
10163
10164   dest = TREE_VALUE (arglist);
10165   /* Actually val for __memset_chk, but it doesn't matter.  */
10166   src = TREE_VALUE (TREE_CHAIN (arglist));
10167   len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
10168   size = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (TREE_CHAIN (arglist))));
10169
10170   /* If SRC and DEST are the same (and not volatile), return DEST
10171      (resp. DEST+LEN for __mempcpy_chk).  */
10172   if (fcode != BUILT_IN_MEMSET_CHK && operand_equal_p (src, dest, 0))
10173     {
10174       if (fcode != BUILT_IN_MEMPCPY_CHK)
10175         return omit_one_operand (TREE_TYPE (TREE_TYPE (fndecl)), dest, len);
10176       else
10177         {
10178           tree temp = fold_convert (TREE_TYPE (dest), len);
10179           temp = fold_build2 (PLUS_EXPR, TREE_TYPE (dest), dest, temp);
10180           return fold_convert (TREE_TYPE (TREE_TYPE (fndecl)), temp);
10181         }
10182     }
10183
10184   if (! host_integerp (size, 1))
10185     return 0;
10186
10187   if (! integer_all_onesp (size))
10188     {
10189       if (! host_integerp (len, 1))
10190         {
10191           /* If LEN is not constant, try MAXLEN too.
10192              For MAXLEN only allow optimizing into non-_ocs function
10193              if SIZE is >= MAXLEN, never convert to __ocs_fail ().  */
10194           if (maxlen == NULL_TREE || ! host_integerp (maxlen, 1))
10195             {
10196               if (fcode == BUILT_IN_MEMPCPY_CHK && ignore)
10197                 {
10198                   /* (void) __mempcpy_chk () can be optimized into
10199                      (void) __memcpy_chk ().  */
10200                   fn = built_in_decls[BUILT_IN_MEMCPY_CHK];
10201                   if (!fn)
10202                     return 0;
10203
10204                   return build_function_call_expr (fn, arglist);
10205                 }
10206               return 0;
10207             }
10208         }
10209       else
10210         maxlen = len;
10211
10212       if (tree_int_cst_lt (size, maxlen))
10213         return 0;
10214     }
10215
10216   arglist = build_tree_list (NULL_TREE, len);
10217   arglist = tree_cons (NULL_TREE, src, arglist);
10218   arglist = tree_cons (NULL_TREE, dest, arglist);
10219
10220   fn = NULL_TREE;
10221   /* If __builtin_mem{cpy,pcpy,move,set}_chk is used, assume
10222      mem{cpy,pcpy,move,set} is available.  */
10223   switch (fcode)
10224     {
10225     case BUILT_IN_MEMCPY_CHK:
10226       fn = built_in_decls[BUILT_IN_MEMCPY];
10227       break;
10228     case BUILT_IN_MEMPCPY_CHK:
10229       fn = built_in_decls[BUILT_IN_MEMPCPY];
10230       break;
10231     case BUILT_IN_MEMMOVE_CHK:
10232       fn = built_in_decls[BUILT_IN_MEMMOVE];
10233       break;
10234     case BUILT_IN_MEMSET_CHK:
10235       fn = built_in_decls[BUILT_IN_MEMSET];
10236       break;
10237     default:
10238       break;
10239     }
10240
10241   if (!fn)
10242     return 0;
10243
10244   return build_function_call_expr (fn, arglist);
10245 }
10246
10247 /* Fold a call to the __st[rp]cpy_chk builtin.
10248    IGNORE is true, if return value can be ignored.  FCODE is the BUILT_IN_*
10249    code of the builtin.  If MAXLEN is not NULL, it is maximum length of
10250    strings passed as second argument.  */
10251
10252 tree
10253 fold_builtin_stxcpy_chk (tree fndecl, tree arglist, tree maxlen, bool ignore,
10254                          enum built_in_function fcode)
10255 {
10256   tree dest, src, size, len, fn;
10257
10258   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE,
10259                          VOID_TYPE))
10260     return 0;
10261
10262   dest = TREE_VALUE (arglist);
10263   src = TREE_VALUE (TREE_CHAIN (arglist));
10264   size = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
10265
10266   /* If SRC and DEST are the same (and not volatile), return DEST.  */
10267   if (fcode == BUILT_IN_STRCPY_CHK && operand_equal_p (src, dest, 0))
10268     return fold_convert (TREE_TYPE (TREE_TYPE (fndecl)), dest);
10269
10270   if (! host_integerp (size, 1))
10271     return 0;
10272
10273   if (! integer_all_onesp (size))
10274     {
10275       len = c_strlen (src, 1);
10276       if (! len || ! host_integerp (len, 1))
10277         {
10278           /* If LEN is not constant, try MAXLEN too.
10279              For MAXLEN only allow optimizing into non-_ocs function
10280              if SIZE is >= MAXLEN, never convert to __ocs_fail ().  */
10281           if (maxlen == NULL_TREE || ! host_integerp (maxlen, 1))
10282             {
10283               if (fcode == BUILT_IN_STPCPY_CHK)
10284                 {
10285                   if (! ignore)
10286                     return 0;
10287
10288                   /* If return value of __stpcpy_chk is ignored,
10289                      optimize into __strcpy_chk.  */
10290                   fn = built_in_decls[BUILT_IN_STRCPY_CHK];
10291                   if (!fn)
10292                     return 0;
10293
10294                   return build_function_call_expr (fn, arglist);
10295                 }
10296
10297               if (! len || TREE_SIDE_EFFECTS (len))
10298                 return 0;
10299
10300               /* If c_strlen returned something, but not a constant,
10301                  transform __strcpy_chk into __memcpy_chk.  */
10302               fn = built_in_decls[BUILT_IN_MEMCPY_CHK];
10303               if (!fn)
10304                 return 0;
10305
10306               len = size_binop (PLUS_EXPR, len, ssize_int (1));
10307               arglist = build_tree_list (NULL_TREE, size);
10308               arglist = tree_cons (NULL_TREE, len, arglist);
10309               arglist = tree_cons (NULL_TREE, src, arglist);
10310               arglist = tree_cons (NULL_TREE, dest, arglist);
10311               return fold_convert (TREE_TYPE (TREE_TYPE (fndecl)),
10312                                    build_function_call_expr (fn, arglist));
10313             }
10314         }
10315       else
10316         maxlen = len;
10317
10318       if (! tree_int_cst_lt (maxlen, size))
10319         return 0;
10320     }
10321
10322   arglist = build_tree_list (NULL_TREE, src);
10323   arglist = tree_cons (NULL_TREE, dest, arglist);
10324
10325   /* If __builtin_st{r,p}cpy_chk is used, assume st{r,p}cpy is available.  */
10326   fn = built_in_decls[fcode == BUILT_IN_STPCPY_CHK
10327                       ? BUILT_IN_STPCPY : BUILT_IN_STRCPY];
10328   if (!fn)
10329     return 0;
10330
10331   return build_function_call_expr (fn, arglist);
10332 }
10333
10334 /* Fold a call to the __strncpy_chk builtin.
10335    If MAXLEN is not NULL, it is maximum length passed as third argument.  */
10336
10337 tree
10338 fold_builtin_strncpy_chk (tree arglist, tree maxlen)
10339 {
10340   tree dest, src, size, len, fn;
10341
10342   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE,
10343                          INTEGER_TYPE, VOID_TYPE))
10344     return 0;
10345
10346   dest = TREE_VALUE (arglist);
10347   src = TREE_VALUE (TREE_CHAIN (arglist));
10348   len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
10349   size = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (TREE_CHAIN (arglist))));
10350
10351   if (! host_integerp (size, 1))
10352     return 0;
10353
10354   if (! integer_all_onesp (size))
10355     {
10356       if (! host_integerp (len, 1))
10357         {
10358           /* If LEN is not constant, try MAXLEN too.
10359              For MAXLEN only allow optimizing into non-_ocs function
10360              if SIZE is >= MAXLEN, never convert to __ocs_fail ().  */
10361           if (maxlen == NULL_TREE || ! host_integerp (maxlen, 1))
10362             return 0;
10363         }
10364       else
10365         maxlen = len;
10366
10367       if (tree_int_cst_lt (size, maxlen))
10368         return 0;
10369     }
10370
10371   arglist = build_tree_list (NULL_TREE, len);
10372   arglist = tree_cons (NULL_TREE, src, arglist);
10373   arglist = tree_cons (NULL_TREE, dest, arglist);
10374
10375   /* If __builtin_strncpy_chk is used, assume strncpy is available.  */
10376   fn = built_in_decls[BUILT_IN_STRNCPY];
10377   if (!fn)
10378     return 0;
10379
10380   return build_function_call_expr (fn, arglist);
10381 }
10382
10383 /* Fold a call to the __strcat_chk builtin FNDECL with ARGLIST.  */
10384
10385 static tree
10386 fold_builtin_strcat_chk (tree fndecl, tree arglist)
10387 {
10388   tree dest, src, size, fn;
10389   const char *p;
10390
10391   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE,
10392                          VOID_TYPE))
10393     return 0;
10394
10395   dest = TREE_VALUE (arglist);
10396   src = TREE_VALUE (TREE_CHAIN (arglist));
10397   size = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
10398
10399   p = c_getstr (src);
10400   /* If the SRC parameter is "", return DEST.  */
10401   if (p && *p == '\0')
10402     return omit_one_operand (TREE_TYPE (TREE_TYPE (fndecl)), dest, src);
10403
10404   if (! host_integerp (size, 1) || ! integer_all_onesp (size))
10405     return 0;
10406
10407   arglist = build_tree_list (NULL_TREE, src);
10408   arglist = tree_cons (NULL_TREE, dest, arglist);
10409
10410   /* If __builtin_strcat_chk is used, assume strcat is available.  */
10411   fn = built_in_decls[BUILT_IN_STRCAT];
10412   if (!fn)
10413     return 0;
10414
10415   return build_function_call_expr (fn, arglist);
10416 }
10417
10418 /* Fold a call to the __strncat_chk builtin EXP.  */
10419
10420 static tree
10421 fold_builtin_strncat_chk (tree fndecl, tree arglist)
10422 {
10423   tree dest, src, size, len, fn;
10424   const char *p;
10425
10426   if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE,
10427                          INTEGER_TYPE, VOID_TYPE))
10428     return 0;
10429
10430   dest = TREE_VALUE (arglist);
10431   src = TREE_VALUE (TREE_CHAIN (arglist));
10432   len = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist)));
10433   size = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (TREE_CHAIN (arglist))));
10434
10435   p = c_getstr (src);
10436   /* If the SRC parameter is "" or if LEN is 0, return DEST.  */
10437   if (p && *p == '\0')
10438     return omit_one_operand (TREE_TYPE (TREE_TYPE (fndecl)), dest, len);
10439   else if (integer_zerop (len))
10440     return omit_one_operand (TREE_TYPE (TREE_TYPE (fndecl)), dest, src);
10441
10442   if (! host_integerp (size, 1))
10443     return 0;
10444
10445   if (! integer_all_onesp (size))
10446     {
10447       tree src_len = c_strlen (src, 1);
10448       if (src_len
10449           && host_integerp (src_len, 1)
10450           && host_integerp (len, 1)
10451           && ! tree_int_cst_lt (len, src_len))
10452         {
10453           /* If LEN >= strlen (SRC), optimize into __strcat_chk.  */
10454           fn = built_in_decls[BUILT_IN_STRCAT_CHK];
10455           if (!fn)
10456             return 0;
10457
10458           arglist = build_tree_list (NULL_TREE, size);
10459           arglist = tree_cons (NULL_TREE, src, arglist);
10460           arglist = tree_cons (NULL_TREE, dest, arglist);
10461           return build_function_call_expr (fn, arglist);
10462         }
10463       return 0;
10464     }
10465
10466   arglist = build_tree_list (NULL_TREE, len);
10467   arglist = tree_cons (NULL_TREE, src, arglist);
10468   arglist = tree_cons (NULL_TREE, dest, arglist);
10469
10470   /* If __builtin_strncat_chk is used, assume strncat is available.  */
10471   fn = built_in_decls[BUILT_IN_STRNCAT];
10472   if (!fn)
10473     return 0;
10474
10475   return build_function_call_expr (fn, arglist);
10476 }
10477
10478 /* Fold a call to __{,v}sprintf_chk with argument list ARGLIST.  Return 0 if
10479    a normal call should be emitted rather than expanding the function
10480    inline.  FCODE is either BUILT_IN_SPRINTF_CHK or BUILT_IN_VSPRINTF_CHK.  */
10481
10482 static tree
10483 fold_builtin_sprintf_chk (tree arglist, enum built_in_function fcode)
10484 {
10485   tree dest, size, len, fn, fmt, flag;
10486   const char *fmt_str;
10487
10488   /* Verify the required arguments in the original call.  */
10489   if (! arglist)
10490     return 0;
10491   dest = TREE_VALUE (arglist);
10492   if (! POINTER_TYPE_P (TREE_TYPE (dest)))
10493     return 0;
10494   arglist = TREE_CHAIN (arglist);
10495   if (! arglist)
10496     return 0;
10497   flag = TREE_VALUE (arglist);
10498   if (TREE_CODE (TREE_TYPE (flag)) != INTEGER_TYPE)
10499     return 0;
10500   arglist = TREE_CHAIN (arglist);
10501   if (! arglist)
10502     return 0;
10503   size = TREE_VALUE (arglist);
10504   if (TREE_CODE (TREE_TYPE (size)) != INTEGER_TYPE)
10505     return 0;
10506   arglist = TREE_CHAIN (arglist);
10507   if (! arglist)
10508     return 0;
10509   fmt = TREE_VALUE (arglist);
10510   if (! POINTER_TYPE_P (TREE_TYPE (fmt)))
10511     return 0;
10512   arglist = TREE_CHAIN (arglist);
10513
10514   if (! host_integerp (size, 1))
10515     return 0;
10516
10517   len = NULL_TREE;
10518
10519   /* Check whether the format is a literal string constant.  */
10520   fmt_str = c_getstr (fmt);
10521   if (fmt_str != NULL)
10522     {
10523       /* If the format doesn't contain % args or %%, we know the size.  */
10524       if (strchr (fmt_str, '%') == 0)
10525         {
10526           if (fcode != BUILT_IN_SPRINTF_CHK || arglist == NULL_TREE)
10527             len = build_int_cstu (size_type_node, strlen (fmt_str));
10528         }
10529       /* If the format is "%s" and first ... argument is a string literal,
10530          we know the size too.  */
10531       else if (fcode == BUILT_IN_SPRINTF_CHK && strcmp (fmt_str, "%s") == 0)
10532         {
10533           tree arg;
10534
10535           if (arglist && !TREE_CHAIN (arglist))
10536             {
10537               arg = TREE_VALUE (arglist);
10538               if (POINTER_TYPE_P (TREE_TYPE (arg)))
10539                 {
10540                   len = c_strlen (arg, 1);
10541                   if (! len || ! host_integerp (len, 1))
10542                     len = NULL_TREE;
10543                 }
10544             }
10545         }
10546     }
10547
10548   if (! integer_all_onesp (size))
10549     {
10550       if (! len || ! tree_int_cst_lt (len, size))
10551         return 0;
10552     }
10553
10554   /* Only convert __{,v}sprintf_chk to {,v}sprintf if flag is 0
10555      or if format doesn't contain % chars or is "%s".  */
10556   if (! integer_zerop (flag))
10557     {
10558       if (fmt_str == NULL)
10559         return 0;
10560       if (strchr (fmt_str, '%') != NULL && strcmp (fmt_str, "%s"))
10561         return 0;
10562     }
10563
10564   arglist = tree_cons (NULL_TREE, fmt, arglist);
10565   arglist = tree_cons (NULL_TREE, dest, arglist);
10566
10567   /* If __builtin_{,v}sprintf_chk is used, assume {,v}sprintf is available.  */
10568   fn = built_in_decls[fcode == BUILT_IN_VSPRINTF_CHK
10569                       ? BUILT_IN_VSPRINTF : BUILT_IN_SPRINTF];
10570   if (!fn)
10571     return 0;
10572
10573   return build_function_call_expr (fn, arglist);
10574 }
10575
10576 /* Fold a call to {,v}snprintf with argument list ARGLIST.  Return 0 if
10577    a normal call should be emitted rather than expanding the function
10578    inline.  FCODE is either BUILT_IN_SNPRINTF_CHK or
10579    BUILT_IN_VSNPRINTF_CHK.  If MAXLEN is not NULL, it is maximum length
10580    passed as second argument.  */
10581
10582 tree
10583 fold_builtin_snprintf_chk (tree arglist, tree maxlen,
10584                            enum built_in_function fcode)
10585 {
10586   tree dest, size, len, fn, fmt, flag;
10587   const char *fmt_str;
10588
10589   /* Verify the required arguments in the original call.  */
10590   if (! arglist)
10591     return 0;
10592   dest = TREE_VALUE (arglist);
10593   if (! POINTER_TYPE_P (TREE_TYPE (dest)))
10594     return 0;
10595   arglist = TREE_CHAIN (arglist);
10596   if (! arglist)
10597     return 0;
10598   len = TREE_VALUE (arglist);
10599   if (TREE_CODE (TREE_TYPE (len)) != INTEGER_TYPE)
10600     return 0;
10601   arglist = TREE_CHAIN (arglist);
10602   if (! arglist)
10603     return 0;
10604   flag = TREE_VALUE (arglist);
10605   if (TREE_CODE (TREE_TYPE (len)) != INTEGER_TYPE)
10606     return 0;
10607   arglist = TREE_CHAIN (arglist);
10608   if (! arglist)
10609     return 0;
10610   size = TREE_VALUE (arglist);
10611   if (TREE_CODE (TREE_TYPE (size)) != INTEGER_TYPE)
10612     return 0;
10613   arglist = TREE_CHAIN (arglist);
10614   if (! arglist)
10615     return 0;
10616   fmt = TREE_VALUE (arglist);
10617   if (! POINTER_TYPE_P (TREE_TYPE (fmt)))
10618     return 0;
10619   arglist = TREE_CHAIN (arglist);
10620
10621   if (! host_integerp (size, 1))
10622     return 0;
10623
10624   if (! integer_all_onesp (size))
10625     {
10626       if (! host_integerp (len, 1))
10627         {
10628           /* If LEN is not constant, try MAXLEN too.
10629              For MAXLEN only allow optimizing into non-_ocs function
10630              if SIZE is >= MAXLEN, never convert to __ocs_fail ().  */
10631           if (maxlen == NULL_TREE || ! host_integerp (maxlen, 1))
10632             return 0;
10633         }
10634       else
10635         maxlen = len;
10636
10637       if (tree_int_cst_lt (size, maxlen))
10638         return 0;
10639     }
10640
10641   /* Only convert __{,v}snprintf_chk to {,v}snprintf if flag is 0
10642      or if format doesn't contain % chars or is "%s".  */
10643   if (! integer_zerop (flag))
10644     {
10645       fmt_str = c_getstr (fmt);
10646       if (fmt_str == NULL)
10647         return 0;
10648       if (strchr (fmt_str, '%') != NULL && strcmp (fmt_str, "%s"))
10649         return 0;
10650     }
10651
10652   arglist = tree_cons (NULL_TREE, fmt, arglist);
10653   arglist = tree_cons (NULL_TREE, len, arglist);
10654   arglist = tree_cons (NULL_TREE, dest, arglist);
10655
10656   /* If __builtin_{,v}snprintf_chk is used, assume {,v}snprintf is
10657      available.  */
10658   fn = built_in_decls[fcode == BUILT_IN_VSNPRINTF_CHK
10659                       ? BUILT_IN_VSNPRINTF : BUILT_IN_SNPRINTF];
10660   if (!fn)
10661     return 0;
10662
10663   return build_function_call_expr (fn, arglist);
10664 }
10665
10666 /* Fold a call to the {,v}printf{,_unlocked} and __{,v}printf_chk builtins.
10667
10668    Return 0 if no simplification was possible, otherwise return the
10669    simplified form of the call as a tree.  FCODE is the BUILT_IN_*
10670    code of the function to be simplified.  */
10671
10672 static tree
10673 fold_builtin_printf (tree fndecl, tree arglist, bool ignore,
10674                      enum built_in_function fcode)
10675 {
10676   tree fmt, fn = NULL_TREE, fn_putchar, fn_puts, arg, call;
10677   const char *fmt_str = NULL;
10678
10679   /* If the return value is used, don't do the transformation.  */
10680   if (! ignore)
10681     return 0;
10682
10683   /* Verify the required arguments in the original call.  */
10684   if (fcode == BUILT_IN_PRINTF_CHK || fcode == BUILT_IN_VPRINTF_CHK)
10685     {
10686       tree flag;
10687
10688       if (! arglist)
10689         return 0;
10690       flag = TREE_VALUE (arglist);
10691       if (TREE_CODE (TREE_TYPE (flag)) != INTEGER_TYPE
10692           || TREE_SIDE_EFFECTS (flag))
10693         return 0;
10694       arglist = TREE_CHAIN (arglist);
10695     }
10696
10697   if (! arglist)
10698     return 0;
10699   fmt = TREE_VALUE (arglist);
10700   if (! POINTER_TYPE_P (TREE_TYPE (fmt)))
10701     return 0;
10702   arglist = TREE_CHAIN (arglist);
10703
10704   /* Check whether the format is a literal string constant.  */
10705   fmt_str = c_getstr (fmt);
10706   if (fmt_str == NULL)
10707     return NULL_TREE;
10708
10709   if (fcode == BUILT_IN_PRINTF_UNLOCKED)
10710     {
10711       fn_putchar = implicit_built_in_decls[BUILT_IN_PUTCHAR_UNLOCKED];
10712       fn_puts = implicit_built_in_decls[BUILT_IN_PUTS_UNLOCKED];
10713     }
10714   else
10715     {
10716       fn_putchar = implicit_built_in_decls[BUILT_IN_PUTCHAR];
10717       fn_puts = implicit_built_in_decls[BUILT_IN_PUTS];
10718     }
10719
10720   if (strcmp (fmt_str, "%s") == 0 || strchr (fmt_str, '%') == NULL)
10721     {
10722       const char *str;
10723
10724       if (strcmp (fmt_str, "%s") == 0)
10725         {
10726           if (fcode == BUILT_IN_VPRINTF || fcode == BUILT_IN_VPRINTF_CHK)
10727             return 0;
10728
10729           if (! arglist
10730               || ! POINTER_TYPE_P (TREE_TYPE (TREE_VALUE (arglist)))
10731               || TREE_CHAIN (arglist))
10732             return 0;
10733
10734           str = c_getstr (TREE_VALUE (arglist));
10735           if (str == NULL)
10736             return 0;
10737         }
10738       else
10739         {
10740           /* The format specifier doesn't contain any '%' characters.  */
10741           if (fcode != BUILT_IN_VPRINTF && fcode != BUILT_IN_VPRINTF_CHK
10742               && arglist)
10743             return 0;
10744           str = fmt_str;
10745         }
10746
10747       /* If the string was "", printf does nothing.  */
10748       if (str[0] == '\0')
10749         return build_int_cst (TREE_TYPE (TREE_TYPE (fndecl)), 0);
10750
10751       /* If the string has length of 1, call putchar.  */
10752       if (str[1] == '\0')
10753         {
10754           /* Given printf("c"), (where c is any one character,)
10755              convert "c"[0] to an int and pass that to the replacement
10756              function.  */
10757           arg = build_int_cst (NULL_TREE, str[0]);
10758           arglist = build_tree_list (NULL_TREE, arg);
10759           fn = fn_putchar;
10760         }
10761       else
10762         {
10763           /* If the string was "string\n", call puts("string").  */
10764           size_t len = strlen (str);
10765           if (str[len - 1] == '\n')
10766             {
10767               /* Create a NUL-terminated string that's one char shorter
10768                  than the original, stripping off the trailing '\n'.  */
10769               char *newstr = alloca (len);
10770               memcpy (newstr, str, len - 1);
10771               newstr[len - 1] = 0;
10772
10773               arg = build_string_literal (len, newstr);
10774               arglist = build_tree_list (NULL_TREE, arg);
10775               fn = fn_puts;
10776             }
10777           else
10778             /* We'd like to arrange to call fputs(string,stdout) here,
10779                but we need stdout and don't have a way to get it yet.  */
10780             return 0;
10781         }
10782     }
10783
10784   /* The other optimizations can be done only on the non-va_list variants.  */
10785   else if (fcode == BUILT_IN_VPRINTF || fcode == BUILT_IN_VPRINTF_CHK)
10786     return 0;
10787
10788   /* If the format specifier was "%s\n", call __builtin_puts(arg).  */
10789   else if (strcmp (fmt_str, "%s\n") == 0)
10790     {
10791       if (! arglist
10792           || ! POINTER_TYPE_P (TREE_TYPE (TREE_VALUE (arglist)))
10793           || TREE_CHAIN (arglist))
10794         return 0;
10795       fn = fn_puts;
10796     }
10797
10798   /* If the format specifier was "%c", call __builtin_putchar(arg).  */
10799   else if (strcmp (fmt_str, "%c") == 0)
10800     {
10801       if (! arglist
10802           || TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) != INTEGER_TYPE
10803           || TREE_CHAIN (arglist))
10804         return 0;
10805       fn = fn_putchar;
10806     }
10807
10808   if (!fn)
10809     return 0;
10810
10811   call = build_function_call_expr (fn, arglist);
10812   return fold_convert (TREE_TYPE (TREE_TYPE (fndecl)), call);
10813 }
10814
10815 /* Fold a call to the {,v}fprintf{,_unlocked} and __{,v}printf_chk builtins.
10816
10817    Return 0 if no simplification was possible, otherwise return the
10818    simplified form of the call as a tree.  FCODE is the BUILT_IN_*
10819    code of the function to be simplified.  */
10820
10821 static tree
10822 fold_builtin_fprintf (tree fndecl, tree arglist, bool ignore,
10823                       enum built_in_function fcode)
10824 {
10825   tree fp, fmt, fn = NULL_TREE, fn_fputc, fn_fputs, arg, call;
10826   const char *fmt_str = NULL;
10827
10828   /* If the return value is used, don't do the transformation.  */
10829   if (! ignore)
10830     return 0;
10831
10832   /* Verify the required arguments in the original call.  */
10833   if (! arglist)
10834     return 0;
10835   fp = TREE_VALUE (arglist);
10836   if (! POINTER_TYPE_P (TREE_TYPE (fp)))
10837     return 0;
10838   arglist = TREE_CHAIN (arglist);
10839
10840   if (fcode == BUILT_IN_FPRINTF_CHK || fcode == BUILT_IN_VFPRINTF_CHK)
10841     {
10842       tree flag;
10843
10844       if (! arglist)
10845         return 0;
10846       flag = TREE_VALUE (arglist);
10847       if (TREE_CODE (TREE_TYPE (flag)) != INTEGER_TYPE
10848           || TREE_SIDE_EFFECTS (flag))
10849         return 0;
10850       arglist = TREE_CHAIN (arglist);
10851     }
10852
10853   if (! arglist)
10854     return 0;
10855   fmt = TREE_VALUE (arglist);
10856   if (! POINTER_TYPE_P (TREE_TYPE (fmt)))
10857     return 0;
10858   arglist = TREE_CHAIN (arglist);
10859
10860   /* Check whether the format is a literal string constant.  */
10861   fmt_str = c_getstr (fmt);
10862   if (fmt_str == NULL)
10863     return NULL_TREE;
10864
10865   if (fcode == BUILT_IN_FPRINTF_UNLOCKED)
10866     {
10867       fn_fputc = implicit_built_in_decls[BUILT_IN_FPUTC_UNLOCKED];
10868       fn_fputs = implicit_built_in_decls[BUILT_IN_FPUTS_UNLOCKED];
10869     }
10870   else
10871     {
10872       fn_fputc = implicit_built_in_decls[BUILT_IN_FPUTC];
10873       fn_fputs = implicit_built_in_decls[BUILT_IN_FPUTS];
10874     }
10875
10876   /* If the format doesn't contain % args or %%, use strcpy.  */
10877   if (strchr (fmt_str, '%') == NULL)
10878     {
10879       if (fcode != BUILT_IN_VFPRINTF && fcode != BUILT_IN_VFPRINTF_CHK
10880           && arglist)
10881         return 0;
10882
10883       /* If the format specifier was "", fprintf does nothing.  */
10884       if (fmt_str[0] == '\0')
10885         {
10886           /* If FP has side-effects, just wait until gimplification is
10887              done.  */
10888           if (TREE_SIDE_EFFECTS (fp))
10889             return 0;
10890
10891           return build_int_cst (TREE_TYPE (TREE_TYPE (fndecl)), 0);
10892         }
10893
10894       /* When "string" doesn't contain %, replace all cases of
10895          fprintf (fp, string) with fputs (string, fp).  The fputs
10896          builtin will take care of special cases like length == 1.  */
10897       arglist = build_tree_list (NULL_TREE, fp);
10898       arglist = tree_cons (NULL_TREE, fmt, arglist);
10899       fn = fn_fputs;
10900     }
10901
10902   /* The other optimizations can be done only on the non-va_list variants.  */
10903   else if (fcode == BUILT_IN_VFPRINTF || fcode == BUILT_IN_VFPRINTF_CHK)
10904     return 0;
10905
10906   /* If the format specifier was "%s", call __builtin_fputs (arg, fp).  */
10907   else if (strcmp (fmt_str, "%s") == 0)
10908     {
10909       if (! arglist
10910           || ! POINTER_TYPE_P (TREE_TYPE (TREE_VALUE (arglist)))
10911           || TREE_CHAIN (arglist))
10912         return 0;
10913       arg = TREE_VALUE (arglist);
10914       arglist = build_tree_list (NULL_TREE, fp);
10915       arglist = tree_cons (NULL_TREE, arg, arglist);
10916       fn = fn_fputs;
10917     }
10918
10919   /* If the format specifier was "%c", call __builtin_fputc (arg, fp).  */
10920   else if (strcmp (fmt_str, "%c") == 0)
10921     {
10922       if (! arglist
10923           || TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) != INTEGER_TYPE
10924           || TREE_CHAIN (arglist))
10925         return 0;
10926       arg = TREE_VALUE (arglist);
10927       arglist = build_tree_list (NULL_TREE, fp);
10928       arglist = tree_cons (NULL_TREE, arg, arglist);
10929       fn = fn_fputc;
10930     }
10931
10932   if (!fn)
10933     return 0;
10934
10935   call = build_function_call_expr (fn, arglist);
10936   return fold_convert (TREE_TYPE (TREE_TYPE (fndecl)), call);
10937 }