gcc/c-common.c

   1 /* Subroutines shared by all languages that are variants of C.
   2    Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
   3    2001, 2002 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, 59 Temple Place - Suite 330, Boston, MA
  20 02111-1307, USA.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "tree.h"
  25 #include "real.h"
  26 #include "flags.h"
  27 #include "toplev.h"
  28 #include "output.h"
  29 #include "c-pragma.h"
  30 #include "rtl.h"
  31 #include "ggc.h"
  32 #include "expr.h"
  33 #include "c-common.h"
  34 #include "tree-inline.h"
  35 #include "diagnostic.h"
  36 #include "tm_p.h"
  37 #include "obstack.h"
  38 #include "cpplib.h"
  39 #include "target.h"
  40 #include "langhooks.h"
  41 #include "except.h"             /* For USING_SJLJ_EXCEPTIONS.  */
  42
  43 cpp_reader *parse_in;           /* Declared in c-pragma.h.  */
  44
  45 /* We let tm.h override the types used here, to handle trivial differences
  46    such as the choice of unsigned int or long unsigned int for size_t.
  47    When machines start needing nontrivial differences in the size type,
  48    it would be best to do something here to figure out automatically
  49    from other information what type to use.  */
  50
  51 #ifndef SIZE_TYPE
  52 #define SIZE_TYPE "long unsigned int"
  53 #endif
  54
  55 #ifndef WCHAR_TYPE
  56 #define WCHAR_TYPE "int"
  57 #endif
  58
  59 /* WCHAR_TYPE gets overridden by -fshort-wchar.  */
  60 #define MODIFIED_WCHAR_TYPE \
  61         (flag_short_wchar ? "short unsigned int" : WCHAR_TYPE)
  62
  63 #ifndef PTRDIFF_TYPE
  64 #define PTRDIFF_TYPE "long int"
  65 #endif
  66
  67 #ifndef WINT_TYPE
  68 #define WINT_TYPE "unsigned int"
  69 #endif
  70
  71 #ifndef INTMAX_TYPE
  72 #define INTMAX_TYPE ((INT_TYPE_SIZE == LONG_LONG_TYPE_SIZE)     \
  73                      ? "int"                                    \
  74                      : ((LONG_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \
  75                         ? "long int"                            \
  76                         : "long long int"))
  77 #endif
  78
  79 #ifndef UINTMAX_TYPE
  80 #define UINTMAX_TYPE ((INT_TYPE_SIZE == LONG_LONG_TYPE_SIZE)    \
  81                      ? "unsigned int"                           \
  82                      : ((LONG_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \
  83                         ? "long unsigned int"                   \
  84                         : "long long unsigned int"))
  85 #endif
  86
  87 #ifndef STDC_0_IN_SYSTEM_HEADERS
  88 #define STDC_0_IN_SYSTEM_HEADERS 0
  89 #endif
  90
  91 #ifndef REGISTER_PREFIX
  92 #define REGISTER_PREFIX ""
  93 #endif
  94
  95 /* The variant of the C language being processed.  */
  96
  97 enum c_language_kind c_language;
  98
  99 /* The following symbols are subsumed in the c_global_trees array, and
 100    listed here individually for documentation purposes.
 101
 102    INTEGER_TYPE and REAL_TYPE nodes for the standard data types.
 103
 104         tree short_integer_type_node;
 105         tree long_integer_type_node;
 106         tree long_long_integer_type_node;
 107
 108         tree short_unsigned_type_node;
 109         tree long_unsigned_type_node;
 110         tree long_long_unsigned_type_node;
 111
 112         tree boolean_type_node;
 113         tree boolean_false_node;
 114         tree boolean_true_node;
 115
 116         tree ptrdiff_type_node;
 117
 118         tree unsigned_char_type_node;
 119         tree signed_char_type_node;
 120         tree wchar_type_node;
 121         tree signed_wchar_type_node;
 122         tree unsigned_wchar_type_node;
 123
 124         tree float_type_node;
 125         tree double_type_node;
 126         tree long_double_type_node;
 127
 128         tree complex_integer_type_node;
 129         tree complex_float_type_node;
 130         tree complex_double_type_node;
 131         tree complex_long_double_type_node;
 132
 133         tree intQI_type_node;
 134         tree intHI_type_node;
 135         tree intSI_type_node;
 136         tree intDI_type_node;
 137         tree intTI_type_node;
 138
 139         tree unsigned_intQI_type_node;
 140         tree unsigned_intHI_type_node;
 141         tree unsigned_intSI_type_node;
 142         tree unsigned_intDI_type_node;
 143         tree unsigned_intTI_type_node;
 144
 145         tree widest_integer_literal_type_node;
 146         tree widest_unsigned_literal_type_node;
 147
 148    Nodes for types `void *' and `const void *'.
 149
 150         tree ptr_type_node, const_ptr_type_node;
 151
 152    Nodes for types `char *' and `const char *'.
 153
 154         tree string_type_node, const_string_type_node;
 155
 156    Type `char[SOMENUMBER]'.
 157    Used when an array of char is needed and the size is irrelevant.
 158
 159         tree char_array_type_node;
 160
 161    Type `int[SOMENUMBER]' or something like it.
 162    Used when an array of int needed and the size is irrelevant.
 163
 164         tree int_array_type_node;
 165
 166    Type `wchar_t[SOMENUMBER]' or something like it.
 167    Used when a wide string literal is created.
 168
 169         tree wchar_array_type_node;
 170
 171    Type `int ()' -- used for implicit declaration of functions.
 172
 173         tree default_function_type;
 174
 175    A VOID_TYPE node, packaged in a TREE_LIST.
 176
 177         tree void_list_node;
 178
 179   The lazily created VAR_DECLs for __FUNCTION__, __PRETTY_FUNCTION__,
 180   and __func__. (C doesn't generate __FUNCTION__ and__PRETTY_FUNCTION__
 181   VAR_DECLS, but C++ does.)
 182
 183         tree function_name_decl_node;
 184         tree pretty_function_name_decl_node;
 185         tree c99_function_name_decl_node;
 186
 187   Stack of nested function name VAR_DECLs.
 188
 189         tree saved_function_name_decls;
 190
 191 */
 192
 193 tree c_global_trees[CTI_MAX];
 194
 195 /* Nonzero if prepreprocessing only.  */
 196 int flag_preprocess_only;
 197
 198 /* Nonzero if an ISO standard was selected.  It rejects macros in the
 199    user's namespace.  */
 200 int flag_iso;
 201
 202 /* Nonzero if -undef was given.  It suppresses target built-in macros
 203    and assertions.  */
 204 int flag_undef;
 205
 206 /* Nonzero means don't recognize the non-ANSI builtin functions.  */
 207
 208 int flag_no_builtin;
 209
 210 /* Nonzero means don't recognize the non-ANSI builtin functions.
 211    -ansi sets this.  */
 212
 213 int flag_no_nonansi_builtin;
 214
 215 /* Nonzero means give `double' the same size as `float'.  */
 216
 217 int flag_short_double;
 218
 219 /* Nonzero means give `wchar_t' the same size as `short'.  */
 220
 221 int flag_short_wchar;
 222
 223 /* Nonzero means allow Microsoft extensions without warnings or errors.  */
 224 int flag_ms_extensions;
 225
 226 /* Nonzero means warn about use of multicharacter literals.  */
 227
 228 int warn_multichar = 1;
 229
 230 /* Nonzero means warn about possible violations of sequence point rules.  */
 231
 232 int warn_sequence_point;
 233
 234 /* Nonzero means to warn about compile-time division by zero.  */
 235 int warn_div_by_zero = 1;
 236
 237 /* Warn about NULL being passed to argument slots marked as requiring
 238    non-NULL.  */
 239
 240 int warn_nonnull;
 241
 242 /* The elements of `ridpointers' are identifier nodes for the reserved
 243    type names and storage classes.  It is indexed by a RID_... value.  */
 244 tree *ridpointers;
 245
 246 tree (*make_fname_decl)                PARAMS ((tree, int));
 247
 248 /* If non-NULL, the address of a language-specific function that
 249    returns 1 for language-specific statement codes.  */
 250 int (*lang_statement_code_p)           PARAMS ((enum tree_code));
 251
 252 /* If non-NULL, the address of a language-specific function that takes
 253    any action required right before expand_function_end is called.  */
 254 void (*lang_expand_function_end)       PARAMS ((void));
 255
 256 /* Nonzero means the expression being parsed will never be evaluated.
 257    This is a count, since unevaluated expressions can nest.  */
 258 int skip_evaluation;
 259
 260 /* Information about how a function name is generated.  */
 261 struct fname_var_t
 262 {
 263   tree *const decl;     /* pointer to the VAR_DECL.  */
 264   const unsigned rid;   /* RID number for the identifier.  */
 265   const int pretty;     /* How pretty is it? */
 266 };
 267
 268 /* The three ways of getting then name of the current function.  */
 269
 270 const struct fname_var_t fname_vars[] =
 271 {
 272   /* C99 compliant __func__, must be first.  */
 273   {&c99_function_name_decl_node, RID_C99_FUNCTION_NAME, 0},
 274   /* GCC __FUNCTION__ compliant.  */
 275   {&function_name_decl_node, RID_FUNCTION_NAME, 0},
 276   /* GCC __PRETTY_FUNCTION__ compliant.  */
 277   {&pretty_function_name_decl_node, RID_PRETTY_FUNCTION_NAME, 1},
 278   {NULL, 0, 0},
 279 };
 280
 281 static int constant_fits_type_p         PARAMS ((tree, tree));
 282
 283 /* Keep a stack of if statements.  We record the number of compound
 284    statements seen up to the if keyword, as well as the line number
 285    and file of the if.  If a potentially ambiguous else is seen, that
 286    fact is recorded; the warning is issued when we can be sure that
 287    the enclosing if statement does not have an else branch.  */
 288 typedef struct
 289 {
 290   int compstmt_count;
 291   int line;
 292   const char *file;
 293   int needs_warning;
 294   tree if_stmt;
 295 } if_elt;
 296
 297 static if_elt *if_stack;
 298
 299 /* Amount of space in the if statement stack.  */
 300 static int if_stack_space = 0;
 301
 302 /* Stack pointer.  */
 303 static int if_stack_pointer = 0;
 304
 305 static void cb_register_builtins PARAMS ((cpp_reader *));
 306
 307 static tree handle_packed_attribute     PARAMS ((tree *, tree, tree, int,
 308                                                  bool *));
 309 static tree handle_nocommon_attribute   PARAMS ((tree *, tree, tree, int,
 310                                                  bool *));
 311 static tree handle_common_attribute     PARAMS ((tree *, tree, tree, int,
 312                                                  bool *));
 313 static tree handle_noreturn_attribute   PARAMS ((tree *, tree, tree, int,
 314                                                  bool *));
 315 static tree handle_noinline_attribute   PARAMS ((tree *, tree, tree, int,
 316                                                  bool *));
 317 static tree handle_always_inline_attribute PARAMS ((tree *, tree, tree, int,
 318                                                     bool *));
 319 static tree handle_used_attribute       PARAMS ((tree *, tree, tree, int,
 320                                                  bool *));
 321 static tree handle_unused_attribute     PARAMS ((tree *, tree, tree, int,
 322                                                  bool *));
 323 static tree handle_const_attribute      PARAMS ((tree *, tree, tree, int,
 324                                                  bool *));
 325 static tree handle_transparent_union_attribute PARAMS ((tree *, tree, tree,
 326                                                         int, bool *));
 327 static tree handle_constructor_attribute PARAMS ((tree *, tree, tree, int,
 328                                                   bool *));
 329 static tree handle_destructor_attribute PARAMS ((tree *, tree, tree, int,
 330                                                  bool *));
 331 static tree handle_mode_attribute       PARAMS ((tree *, tree, tree, int,
 332                                                  bool *));
 333 static tree handle_section_attribute    PARAMS ((tree *, tree, tree, int,
 334                                                  bool *));
 335 static tree handle_aligned_attribute    PARAMS ((tree *, tree, tree, int,
 336                                                  bool *));
 337 static tree handle_weak_attribute       PARAMS ((tree *, tree, tree, int,
 338                                                  bool *));
 339 static tree handle_alias_attribute      PARAMS ((tree *, tree, tree, int,
 340                                                  bool *));
 341 static tree handle_visibility_attribute PARAMS ((tree *, tree, tree, int,
 342                                                  bool *));
 343 static tree handle_no_instrument_function_attribute PARAMS ((tree *, tree,
 344                                                              tree, int,
 345                                                              bool *));
 346 static tree handle_malloc_attribute     PARAMS ((tree *, tree, tree, int,
 347                                                  bool *));
 348 static tree handle_no_limit_stack_attribute PARAMS ((tree *, tree, tree, int,
 349                                                      bool *));
 350 static tree handle_pure_attribute       PARAMS ((tree *, tree, tree, int,
 351                                                  bool *));
 352 static tree handle_deprecated_attribute PARAMS ((tree *, tree, tree, int,
 353                                                  bool *));
 354 static tree handle_vector_size_attribute PARAMS ((tree *, tree, tree, int,
 355                                                   bool *));
 356 static tree handle_nonnull_attribute    PARAMS ((tree *, tree, tree, int,
 357                                                  bool *));
 358 static tree handle_nothrow_attribute    PARAMS ((tree *, tree, tree, int,
 359                                                  bool *));
 360 static tree vector_size_helper PARAMS ((tree, tree));
 361
 362 static void check_function_nonnull      PARAMS ((tree, tree));
 363 static void check_nonnull_arg           PARAMS ((void *, tree,
 364                                                  unsigned HOST_WIDE_INT));
 365 static bool nonnull_check_p             PARAMS ((tree, unsigned HOST_WIDE_INT));
 366 static bool get_nonnull_operand         PARAMS ((tree,
 367                                                  unsigned HOST_WIDE_INT *));
 368 void builtin_define_std PARAMS ((const char *));
 369 static void builtin_define_with_value PARAMS ((const char *, const char *,
 370                                                int));
 371 static void builtin_define_type_max PARAMS ((const char *, tree, int));
 372
 373 /* Table of machine-independent attributes common to all C-like languages.  */
 374 const struct attribute_spec c_common_attribute_table[] =
 375 {
 376   /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */
 377   { "packed",                 0, 0, false, false, false,
 378                               handle_packed_attribute },
 379   { "nocommon",               0, 0, true,  false, false,
 380                               handle_nocommon_attribute },
 381   { "common",                 0, 0, true,  false, false,
 382                               handle_common_attribute },
 383   /* FIXME: logically, noreturn attributes should be listed as
 384      "false, true, true" and apply to function types.  But implementing this
 385      would require all the places in the compiler that use TREE_THIS_VOLATILE
 386      on a decl to identify non-returning functions to be located and fixed
 387      to check the function type instead.  */
 388   { "noreturn",               0, 0, true,  false, false,
 389                               handle_noreturn_attribute },
 390   { "volatile",               0, 0, true,  false, false,
 391                               handle_noreturn_attribute },
 392   { "noinline",               0, 0, true,  false, false,
 393                               handle_noinline_attribute },
 394   { "always_inline",          0, 0, true,  false, false,
 395                               handle_always_inline_attribute },
 396   { "used",                   0, 0, true,  false, false,
 397                               handle_used_attribute },
 398   { "unused",                 0, 0, false, false, false,
 399                               handle_unused_attribute },
 400   /* The same comments as for noreturn attributes apply to const ones.  */
 401   { "const",                  0, 0, true,  false, false,
 402                               handle_const_attribute },
 403   { "transparent_union",      0, 0, false, false, false,
 404                               handle_transparent_union_attribute },
 405   { "constructor",            0, 0, true,  false, false,
 406                               handle_constructor_attribute },
 407   { "destructor",             0, 0, true,  false, false,
 408                               handle_destructor_attribute },
 409   { "mode",                   1, 1, false,  true, false,
 410                               handle_mode_attribute },
 411   { "section",                1, 1, true,  false, false,
 412                               handle_section_attribute },
 413   { "aligned",                0, 1, false, false, false,
 414                               handle_aligned_attribute },
 415   { "weak",                   0, 0, true,  false, false,
 416                               handle_weak_attribute },
 417   { "alias",                  1, 1, true,  false, false,
 418                               handle_alias_attribute },
 419   { "no_instrument_function", 0, 0, true,  false, false,
 420                               handle_no_instrument_function_attribute },
 421   { "malloc",                 0, 0, true,  false, false,
 422                               handle_malloc_attribute },
 423   { "no_stack_limit",         0, 0, true,  false, false,
 424                               handle_no_limit_stack_attribute },
 425   { "pure",                   0, 0, true,  false, false,
 426                               handle_pure_attribute },
 427   { "deprecated",             0, 0, false, false, false,
 428                               handle_deprecated_attribute },
 429   { "vector_size",            1, 1, false, true, false,
 430                               handle_vector_size_attribute },
 431   { "visibility",             1, 1, true,  false, false,
 432                               handle_visibility_attribute },
 433   { "nonnull",                0, -1, false, true, true,
 434                               handle_nonnull_attribute },
 435   { "nothrow",                0, 0, true,  false, false,
 436                               handle_nothrow_attribute },
 437   { "may_alias",              0, 0, false, true, false, NULL },
 438   { NULL,                     0, 0, false, false, false, NULL }
 439 };
 440
 441 /* Give the specifications for the format attributes, used by C and all
 442    descendents.  */
 443
 444 const struct attribute_spec c_common_format_attribute_table[] =
 445 {
 446   /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */
 447   { "format",                 3, 3, false, true,  true,
 448                               handle_format_attribute },
 449   { "format_arg",             1, 1, false, true,  true,
 450                               handle_format_arg_attribute },
 451   { NULL,                     0, 0, false, false, false, NULL }
 452 };
 453
 454 /* Record the start of an if-then, and record the start of it
 455    for ambiguous else detection.
 456
 457    COND is the condition for the if-then statement.
 458
 459    IF_STMT is the statement node that has already been created for
 460    this if-then statement.  It is created before parsing the
 461    condition to keep line number information accurate.  */
 462
 463 void
 464 c_expand_start_cond (cond, compstmt_count, if_stmt)
 465      tree cond;
 466      int compstmt_count;
 467      tree if_stmt;
 468 {
 469   /* Make sure there is enough space on the stack.  */
 470   if (if_stack_space == 0)
 471     {
 472       if_stack_space = 10;
 473       if_stack = (if_elt *) xmalloc (10 * sizeof (if_elt));
 474     }
 475   else if (if_stack_space == if_stack_pointer)
 476     {
 477       if_stack_space += 10;
 478       if_stack = (if_elt *) xrealloc (if_stack, if_stack_space * sizeof (if_elt));
 479     }
 480
 481   IF_COND (if_stmt) = cond;
 482   add_stmt (if_stmt);
 483
 484   /* Record this if statement.  */
 485   if_stack[if_stack_pointer].compstmt_count = compstmt_count;
 486   if_stack[if_stack_pointer].file = input_filename;
 487   if_stack[if_stack_pointer].line = lineno;
 488   if_stack[if_stack_pointer].needs_warning = 0;
 489   if_stack[if_stack_pointer].if_stmt = if_stmt;
 490   if_stack_pointer++;
 491 }
 492
 493 /* Called after the then-clause for an if-statement is processed.  */
 494
 495 void
 496 c_finish_then ()
 497 {
 498   tree if_stmt = if_stack[if_stack_pointer - 1].if_stmt;
 499   RECHAIN_STMTS (if_stmt, THEN_CLAUSE (if_stmt));
 500 }
 501
 502 /* Record the end of an if-then.  Optionally warn if a nested
 503    if statement had an ambiguous else clause.  */
 504
 505 void
 506 c_expand_end_cond ()
 507 {
 508   if_stack_pointer--;
 509   if (if_stack[if_stack_pointer].needs_warning)
 510     warning_with_file_and_line (if_stack[if_stack_pointer].file,
 511                                 if_stack[if_stack_pointer].line,
 512                                 "suggest explicit braces to avoid ambiguous `else'");
 513   last_expr_type = NULL_TREE;
 514 }
 515
 516 /* Called between the then-clause and the else-clause
 517    of an if-then-else.  */
 518
 519 void
 520 c_expand_start_else ()
 521 {
 522   /* An ambiguous else warning must be generated for the enclosing if
 523      statement, unless we see an else branch for that one, too.  */
 524   if (warn_parentheses
 525       && if_stack_pointer > 1
 526       && (if_stack[if_stack_pointer - 1].compstmt_count
 527           == if_stack[if_stack_pointer - 2].compstmt_count))
 528     if_stack[if_stack_pointer - 2].needs_warning = 1;
 529
 530   /* Even if a nested if statement had an else branch, it can't be
 531      ambiguous if this one also has an else.  So don't warn in that
 532      case.  Also don't warn for any if statements nested in this else.  */
 533   if_stack[if_stack_pointer - 1].needs_warning = 0;
 534   if_stack[if_stack_pointer - 1].compstmt_count--;
 535 }
 536
 537 /* Called after the else-clause for an if-statement is processed.  */
 538
 539 void
 540 c_finish_else ()
 541 {
 542   tree if_stmt = if_stack[if_stack_pointer - 1].if_stmt;
 543   RECHAIN_STMTS (if_stmt, ELSE_CLAUSE (if_stmt));
 544 }
 545
 546 /* Begin an if-statement.  Returns a newly created IF_STMT if
 547    appropriate.
 548
 549    Unlike the C++ front-end, we do not call add_stmt here; it is
 550    probably safe to do so, but I am not very familiar with this
 551    code so I am being extra careful not to change its behavior
 552    beyond what is strictly necessary for correctness.  */
 553
 554 tree
 555 c_begin_if_stmt ()
 556 {
 557   tree r;
 558   r = build_stmt (IF_STMT, NULL_TREE, NULL_TREE, NULL_TREE);
 559   return r;
 560 }
 561
 562 /* Begin a while statement.  Returns a newly created WHILE_STMT if
 563    appropriate.
 564
 565    Unlike the C++ front-end, we do not call add_stmt here; it is
 566    probably safe to do so, but I am not very familiar with this
 567    code so I am being extra careful not to change its behavior
 568    beyond what is strictly necessary for correctness.  */
 569
 570 tree
 571 c_begin_while_stmt ()
 572 {
 573   tree r;
 574   r = build_stmt (WHILE_STMT, NULL_TREE, NULL_TREE);
 575   return r;
 576 }
 577
 578 void
 579 c_finish_while_stmt_cond (cond, while_stmt)
 580      tree while_stmt;
 581      tree cond;
 582 {
 583   WHILE_COND (while_stmt) = cond;
 584 }
 585
 586 /* Push current bindings for the function name VAR_DECLS.  */
 587
 588 void
 589 start_fname_decls ()
 590 {
 591   unsigned ix;
 592   tree saved = NULL_TREE;
 593
 594   for (ix = 0; fname_vars[ix].decl; ix++)
 595     {
 596       tree decl = *fname_vars[ix].decl;
 597
 598       if (decl)
 599         {
 600           saved = tree_cons (decl, build_int_2 (ix, 0), saved);
 601           *fname_vars[ix].decl = NULL_TREE;
 602         }
 603     }
 604   if (saved || saved_function_name_decls)
 605     /* Normally they'll have been NULL, so only push if we've got a
 606        stack, or they are non-NULL.  */
 607     saved_function_name_decls = tree_cons (saved, NULL_TREE,
 608                                            saved_function_name_decls);
 609 }
 610
 611 /* Finish up the current bindings, adding them into the
 612    current function's statement tree. This is done by wrapping the
 613    function's body in a COMPOUND_STMT containing these decls too. This
 614    must be done _before_ finish_stmt_tree is called. If there is no
 615    current function, we must be at file scope and no statements are
 616    involved. Pop the previous bindings.  */
 617
 618 void
 619 finish_fname_decls ()
 620 {
 621   unsigned ix;
 622   tree body = NULL_TREE;
 623   tree stack = saved_function_name_decls;
 624
 625   for (; stack && TREE_VALUE (stack); stack = TREE_CHAIN (stack))
 626     body = chainon (TREE_VALUE (stack), body);
 627
 628   if (body)
 629     {
 630       /* They were called into existence, so add to statement tree.  */
 631       body = chainon (body,
 632                       TREE_CHAIN (DECL_SAVED_TREE (current_function_decl)));
 633       body = build_stmt (COMPOUND_STMT, body);
 634
 635       COMPOUND_STMT_NO_SCOPE (body) = 1;
 636       TREE_CHAIN (DECL_SAVED_TREE (current_function_decl)) = body;
 637     }
 638
 639   for (ix = 0; fname_vars[ix].decl; ix++)
 640     *fname_vars[ix].decl = NULL_TREE;
 641
 642   if (stack)
 643     {
 644       /* We had saved values, restore them.  */
 645       tree saved;
 646
 647       for (saved = TREE_PURPOSE (stack); saved; saved = TREE_CHAIN (saved))
 648         {
 649           tree decl = TREE_PURPOSE (saved);
 650           unsigned ix = TREE_INT_CST_LOW (TREE_VALUE (saved));
 651
 652           *fname_vars[ix].decl = decl;
 653         }
 654       stack = TREE_CHAIN (stack);
 655     }
 656   saved_function_name_decls = stack;
 657 }
 658
 659 /* Return the text name of the current function, suitable prettified
 660    by PRETTY_P.  */
 661
 662 const char *
 663 fname_as_string (pretty_p)
 664      int pretty_p;
 665 {
 666   const char *name = NULL;
 667
 668   if (pretty_p)
 669     name = (current_function_decl
 670             ? (*lang_hooks.decl_printable_name) (current_function_decl, 2)
 671             : "top level");
 672   else if (current_function_decl && DECL_NAME (current_function_decl))
 673     name = IDENTIFIER_POINTER (DECL_NAME (current_function_decl));
 674   else
 675     name = "";
 676   return name;
 677 }
 678
 679 /* Return the text name of the current function, formatted as
 680    required by the supplied RID value.  */
 681
 682 const char *
 683 fname_string (rid)
 684      unsigned rid;
 685 {
 686   unsigned ix;
 687
 688   for (ix = 0; fname_vars[ix].decl; ix++)
 689     if (fname_vars[ix].rid == rid)
 690       break;
 691   return fname_as_string (fname_vars[ix].pretty);
 692 }
 693
 694 /* Return the VAR_DECL for a const char array naming the current
 695    function. If the VAR_DECL has not yet been created, create it
 696    now. RID indicates how it should be formatted and IDENTIFIER_NODE
 697    ID is its name (unfortunately C and C++ hold the RID values of
 698    keywords in different places, so we can't derive RID from ID in
 699    this language independent code.  */
 700
 701 tree
 702 fname_decl (rid, id)
 703      unsigned rid;
 704      tree id;
 705 {
 706   unsigned ix;
 707   tree decl = NULL_TREE;
 708
 709   for (ix = 0; fname_vars[ix].decl; ix++)
 710     if (fname_vars[ix].rid == rid)
 711       break;
 712
 713   decl = *fname_vars[ix].decl;
 714   if (!decl)
 715     {
 716       tree saved_last_tree = last_tree;
 717
 718       decl = (*make_fname_decl) (id, fname_vars[ix].pretty);
 719       if (last_tree != saved_last_tree)
 720         {
 721           /* We created some statement tree for the decl. This belongs
 722              at the start of the function, so remove it now and reinsert
 723              it after the function is complete.  */
 724           tree stmts = TREE_CHAIN (saved_last_tree);
 725
 726           TREE_CHAIN (saved_last_tree) = NULL_TREE;
 727           last_tree = saved_last_tree;
 728           saved_function_name_decls = tree_cons (decl, stmts,
 729                                                  saved_function_name_decls);
 730         }
 731       *fname_vars[ix].decl = decl;
 732     }
 733   if (!ix && !current_function_decl)
 734     pedwarn_with_decl (decl, "`%s' is not defined outside of function scope");
 735
 736   return decl;
 737 }
 738
 739 /* Given a STRING_CST, give it a suitable array-of-chars data type.  */
 740
 741 tree
 742 fix_string_type (value)
 743       tree value;
 744 {
 745   const int wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
 746   const int wide_flag = TREE_TYPE (value) == wchar_array_type_node;
 747   const int nchars_max = flag_isoc99 ? 4095 : 509;
 748   int length = TREE_STRING_LENGTH (value);
 749   int nchars;
 750
 751   /* Compute the number of elements, for the array type.  */
 752   nchars = wide_flag ? length / wchar_bytes : length;
 753
 754   if (pedantic && nchars - 1 > nchars_max && c_language == clk_c)
 755     pedwarn ("string length `%d' is greater than the length `%d' ISO C%d compilers are required to support",
 756              nchars - 1, nchars_max, flag_isoc99 ? 99 : 89);
 757
 758   /* Create the array type for the string constant.
 759      -Wwrite-strings says make the string constant an array of const char
 760      so that copying it to a non-const pointer will get a warning.
 761      For C++, this is the standard behavior.  */
 762   if (flag_const_strings && ! flag_writable_strings)
 763     {
 764       tree elements
 765         = build_type_variant (wide_flag ? wchar_type_node : char_type_node,
 766                               1, 0);
 767       TREE_TYPE (value)
 768         = build_array_type (elements,
 769                             build_index_type (build_int_2 (nchars - 1, 0)));
 770     }
 771   else
 772     TREE_TYPE (value)
 773       = build_array_type (wide_flag ? wchar_type_node : char_type_node,
 774                           build_index_type (build_int_2 (nchars - 1, 0)));
 775
 776   TREE_CONSTANT (value) = 1;
 777   TREE_READONLY (value) = ! flag_writable_strings;
 778   TREE_STATIC (value) = 1;
 779   return value;
 780 }
 781
 782 /* Given a VARRAY of STRING_CST nodes, concatenate them into one
 783    STRING_CST.  */
 784
 785 tree
 786 combine_strings (strings)
 787      varray_type strings;
 788 {
 789   const int wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
 790   const int nstrings = VARRAY_ACTIVE_SIZE (strings);
 791   tree value, t;
 792   int length = 1;
 793   int wide_length = 0;
 794   int wide_flag = 0;
 795   int i;
 796   char *p, *q;
 797
 798   /* Don't include the \0 at the end of each substring.  Count wide
 799      strings and ordinary strings separately.  */
 800   for (i = 0; i < nstrings; ++i)
 801     {
 802       t = VARRAY_TREE (strings, i);
 803
 804       if (TREE_TYPE (t) == wchar_array_type_node)
 805         {
 806           wide_length += TREE_STRING_LENGTH (t) - wchar_bytes;
 807           wide_flag = 1;
 808         }
 809       else
 810         {
 811           length += (TREE_STRING_LENGTH (t) - 1);
 812           if (C_ARTIFICIAL_STRING_P (t) && !in_system_header)
 813             warning ("concatenation of string literals with __FUNCTION__ is deprecated");
 814         }
 815     }
 816
 817   /* If anything is wide, the non-wides will be converted,
 818      which makes them take more space.  */
 819   if (wide_flag)
 820     length = length * wchar_bytes + wide_length;
 821
 822   p = xmalloc (length);
 823
 824   /* Copy the individual strings into the new combined string.
 825      If the combined string is wide, convert the chars to ints
 826      for any individual strings that are not wide.  */
 827
 828   q = p;
 829   for (i = 0; i < nstrings; ++i)
 830     {
 831       int len, this_wide;
 832
 833       t = VARRAY_TREE (strings, i);
 834       this_wide = TREE_TYPE (t) == wchar_array_type_node;
 835       len = TREE_STRING_LENGTH (t) - (this_wide ? wchar_bytes : 1);
 836       if (this_wide == wide_flag)
 837         {
 838           memcpy (q, TREE_STRING_POINTER (t), len);
 839           q += len;
 840         }
 841       else
 842         {
 843           const int nzeros = (TYPE_PRECISION (wchar_type_node)
 844                               / BITS_PER_UNIT) - 1;
 845           int j, k;
 846
 847           if (BYTES_BIG_ENDIAN)
 848             {
 849               for (k = 0; k < len; k++)
 850                 {
 851                   for (j = 0; j < nzeros; j++)
 852                     *q++ = 0;
 853                   *q++ = TREE_STRING_POINTER (t)[k];
 854                 }
 855             }
 856           else
 857             {
 858               for (k = 0; k < len; k++)
 859                 {
 860                   *q++ = TREE_STRING_POINTER (t)[k];
 861                   for (j = 0; j < nzeros; j++)
 862                     *q++ = 0;
 863                 }
 864             }
 865         }
 866     }
 867
 868   /* Nul terminate the string.  */
 869   if (wide_flag)
 870     {
 871       for (i = 0; i < wchar_bytes; i++)
 872         *q++ = 0;
 873     }
 874   else
 875     *q = 0;
 876
 877   value = build_string (length, p);
 878   free (p);
 879
 880   if (wide_flag)
 881     TREE_TYPE (value) = wchar_array_type_node;
 882   else
 883     TREE_TYPE (value) = char_array_type_node;
 884
 885   return value;
 886 }
 887 \f
 888 static int is_valid_printf_arglist PARAMS ((tree));
 889 static rtx c_expand_builtin PARAMS ((tree, rtx, enum machine_mode, enum expand_modifier));
 890 static rtx c_expand_builtin_printf PARAMS ((tree, rtx, enum machine_mode,
 891                                             enum expand_modifier, int, int));
 892 static rtx c_expand_builtin_fprintf PARAMS ((tree, rtx, enum machine_mode,
 893                                              enum expand_modifier, int, int));
 894 \f
 895 /* Print a warning if a constant expression had overflow in folding.
 896    Invoke this function on every expression that the language
 897    requires to be a constant expression.
 898    Note the ANSI C standard says it is erroneous for a
 899    constant expression to overflow.  */
 900
 901 void
 902 constant_expression_warning (value)
 903      tree value;
 904 {
 905   if ((TREE_CODE (value) == INTEGER_CST || TREE_CODE (value) == REAL_CST
 906        || TREE_CODE (value) == VECTOR_CST
 907        || TREE_CODE (value) == COMPLEX_CST)
 908       && TREE_CONSTANT_OVERFLOW (value) && pedantic)
 909     pedwarn ("overflow in constant expression");
 910 }
 911
 912 /* Print a warning if an expression had overflow in folding.
 913    Invoke this function on every expression that
 914    (1) appears in the source code, and
 915    (2) might be a constant expression that overflowed, and
 916    (3) is not already checked by convert_and_check;
 917    however, do not invoke this function on operands of explicit casts.  */
 918
 919 void
 920 overflow_warning (value)
 921      tree value;
 922 {
 923   if ((TREE_CODE (value) == INTEGER_CST
 924        || (TREE_CODE (value) == COMPLEX_CST
 925            && TREE_CODE (TREE_REALPART (value)) == INTEGER_CST))
 926       && TREE_OVERFLOW (value))
 927     {
 928       TREE_OVERFLOW (value) = 0;
 929       if (skip_evaluation == 0)
 930         warning ("integer overflow in expression");
 931     }
 932   else if ((TREE_CODE (value) == REAL_CST
 933             || (TREE_CODE (value) == COMPLEX_CST
 934                 && TREE_CODE (TREE_REALPART (value)) == REAL_CST))
 935            && TREE_OVERFLOW (value))
 936     {
 937       TREE_OVERFLOW (value) = 0;
 938       if (skip_evaluation == 0)
 939         warning ("floating point overflow in expression");
 940     }
 941   else if (TREE_CODE (value) == VECTOR_CST && TREE_OVERFLOW (value))
 942     {
 943       TREE_OVERFLOW (value) = 0;
 944       if (skip_evaluation == 0)
 945         warning ("vector overflow in expression");
 946     }
 947 }
 948
 949 /* Print a warning if a large constant is truncated to unsigned,
 950    or if -Wconversion is used and a constant < 0 is converted to unsigned.
 951    Invoke this function on every expression that might be implicitly
 952    converted to an unsigned type.  */
 953
 954 void
 955 unsigned_conversion_warning (result, operand)
 956      tree result, operand;
 957 {
 958   tree type = TREE_TYPE (result);
 959
 960   if (TREE_CODE (operand) == INTEGER_CST
 961       && TREE_CODE (type) == INTEGER_TYPE
 962       && TREE_UNSIGNED (type)
 963       && skip_evaluation == 0
 964       && !int_fits_type_p (operand, type))
 965     {
 966       if (!int_fits_type_p (operand, c_common_signed_type (type)))
 967         /* This detects cases like converting -129 or 256 to unsigned char.  */
 968         warning ("large integer implicitly truncated to unsigned type");
 969       else if (warn_conversion)
 970         warning ("negative integer implicitly converted to unsigned type");
 971     }
 972 }
 973
 974 /* Nonzero if constant C has a value that is permissible
 975    for type TYPE (an INTEGER_TYPE).  */
 976
 977 static int
 978 constant_fits_type_p (c, type)
 979      tree c, type;
 980 {
 981   if (TREE_CODE (c) == INTEGER_CST)
 982     return int_fits_type_p (c, type);
 983
 984   c = convert (type, c);
 985   return !TREE_OVERFLOW (c);
 986 }
 987
 988 /* Convert EXPR to TYPE, warning about conversion problems with constants.
 989    Invoke this function on every expression that is converted implicitly,
 990    i.e. because of language rules and not because of an explicit cast.  */
 991
 992 tree
 993 convert_and_check (type, expr)
 994      tree type, expr;
 995 {
 996   tree t = convert (type, expr);
 997   if (TREE_CODE (t) == INTEGER_CST)
 998     {
 999       if (TREE_OVERFLOW (t))
1000         {
1001           TREE_OVERFLOW (t) = 0;
1002
1003           /* Do not diagnose overflow in a constant expression merely
1004              because a conversion overflowed.  */
1005           TREE_CONSTANT_OVERFLOW (t) = TREE_CONSTANT_OVERFLOW (expr);
1006
1007           /* No warning for converting 0x80000000 to int.  */
1008           if (!(TREE_UNSIGNED (type) < TREE_UNSIGNED (TREE_TYPE (expr))
1009                 && TREE_CODE (TREE_TYPE (expr)) == INTEGER_TYPE
1010                 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (expr))))
1011             /* If EXPR fits in the unsigned version of TYPE,
1012                don't warn unless pedantic.  */
1013             if ((pedantic
1014                  || TREE_UNSIGNED (type)
1015                  || ! constant_fits_type_p (expr,
1016                                             c_common_unsigned_type (type)))
1017                 && skip_evaluation == 0)
1018               warning ("overflow in implicit constant conversion");
1019         }
1020       else
1021         unsigned_conversion_warning (t, expr);
1022     }
1023   return t;
1024 }
1025 \f
1026 /* A node in a list that describes references to variables (EXPR), which are
1027    either read accesses if WRITER is zero, or write accesses, in which case
1028    WRITER is the parent of EXPR.  */
1029 struct tlist
1030 {
1031   struct tlist *next;
1032   tree expr, writer;
1033 };
1034
1035 /* Used to implement a cache the results of a call to verify_tree.  We only
1036    use this for SAVE_EXPRs.  */
1037 struct tlist_cache
1038 {
1039   struct tlist_cache *next;
1040   struct tlist *cache_before_sp;
1041   struct tlist *cache_after_sp;
1042   tree expr;
1043 };
1044
1045 /* Obstack to use when allocating tlist structures, and corresponding
1046    firstobj.  */
1047 static struct obstack tlist_obstack;
1048 static char *tlist_firstobj = 0;
1049
1050 /* Keep track of the identifiers we've warned about, so we can avoid duplicate
1051    warnings.  */
1052 static struct tlist *warned_ids;
1053 /* SAVE_EXPRs need special treatment.  We process them only once and then
1054    cache the results.  */
1055 static struct tlist_cache *save_expr_cache;
1056
1057 static void add_tlist PARAMS ((struct tlist **, struct tlist *, tree, int));
1058 static void merge_tlist PARAMS ((struct tlist **, struct tlist *, int));
1059 static void verify_tree PARAMS ((tree, struct tlist **, struct tlist **, tree));
1060 static int warning_candidate_p PARAMS ((tree));
1061 static void warn_for_collisions PARAMS ((struct tlist *));
1062 static void warn_for_collisions_1 PARAMS ((tree, tree, struct tlist *, int));
1063 static struct tlist *new_tlist PARAMS ((struct tlist *, tree, tree));
1064 static void verify_sequence_points PARAMS ((tree));
1065
1066 /* Create a new struct tlist and fill in its fields.  */
1067 static struct tlist *
1068 new_tlist (next, t, writer)
1069      struct tlist *next;
1070      tree t;
1071      tree writer;
1072 {
1073   struct tlist *l;
1074   l = (struct tlist *) obstack_alloc (&tlist_obstack, sizeof *l);
1075   l->next = next;
1076   l->expr = t;
1077   l->writer = writer;
1078   return l;
1079 }
1080
1081 /* Add duplicates of the nodes found in ADD to the list *TO.  If EXCLUDE_WRITER
1082    is nonnull, we ignore any node we find which has a writer equal to it.  */
1083
1084 static void
1085 add_tlist (to, add, exclude_writer, copy)
1086      struct tlist **to;
1087      struct tlist *add;
1088      tree exclude_writer;
1089      int copy;
1090 {
1091   while (add)
1092     {
1093       struct tlist *next = add->next;
1094       if (! copy)
1095         add->next = *to;
1096       if (! exclude_writer || add->writer != exclude_writer)
1097         *to = copy ? new_tlist (*to, add->expr, add->writer) : add;
1098       add = next;
1099     }
1100 }
1101
1102 /* Merge the nodes of ADD into TO.  This merging process is done so that for
1103    each variable that already exists in TO, no new node is added; however if
1104    there is a write access recorded in ADD, and an occurrence on TO is only
1105    a read access, then the occurrence in TO will be modified to record the
1106    write.  */
1107
1108 static void
1109 merge_tlist (to, add, copy)
1110      struct tlist **to;
1111      struct tlist *add;
1112      int copy;
1113 {
1114   struct tlist **end = to;
1115
1116   while (*end)
1117     end = &(*end)->next;
1118
1119   while (add)
1120     {
1121       int found = 0;
1122       struct tlist *tmp2;
1123       struct tlist *next = add->next;
1124
1125       for (tmp2 = *to; tmp2; tmp2 = tmp2->next)
1126         if (tmp2->expr == add->expr)
1127           {
1128             found = 1;
1129             if (! tmp2->writer)
1130               tmp2->writer = add->writer;
1131           }
1132       if (! found)
1133         {
1134           *end = copy ? add : new_tlist (NULL, add->expr, add->writer);
1135           end = &(*end)->next;
1136           *end = 0;
1137         }
1138       add = next;
1139     }
1140 }
1141
1142 /* WRITTEN is a variable, WRITER is its parent.  Warn if any of the variable
1143    references in list LIST conflict with it, excluding reads if ONLY writers
1144    is nonzero.  */
1145
1146 static void
1147 warn_for_collisions_1 (written, writer, list, only_writes)
1148      tree written, writer;
1149      struct tlist *list;
1150      int only_writes;
1151 {
1152   struct tlist *tmp;
1153
1154   /* Avoid duplicate warnings.  */
1155   for (tmp = warned_ids; tmp; tmp = tmp->next)
1156     if (tmp->expr == written)
1157       return;
1158
1159   while (list)
1160     {
1161       if (list->expr == written
1162           && list->writer != writer
1163           && (! only_writes || list->writer))
1164         {
1165           warned_ids = new_tlist (warned_ids, written, NULL_TREE);
1166           warning ("operation on `%s' may be undefined",
1167                    IDENTIFIER_POINTER (DECL_NAME (list->expr)));
1168         }
1169       list = list->next;
1170     }
1171 }
1172
1173 /* Given a list LIST of references to variables, find whether any of these
1174    can cause conflicts due to missing sequence points.  */
1175
1176 static void
1177 warn_for_collisions (list)
1178      struct tlist *list;
1179 {
1180   struct tlist *tmp;
1181
1182   for (tmp = list; tmp; tmp = tmp->next)
1183     {
1184       if (tmp->writer)
1185         warn_for_collisions_1 (tmp->expr, tmp->writer, list, 0);
1186     }
1187 }
1188
1189 /* Return nonzero if X is a tree that can be verified by the sequence point
1190    warnings.  */
1191 static int
1192 warning_candidate_p (x)
1193      tree x;
1194 {
1195   return TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == PARM_DECL;
1196 }
1197
1198 /* Walk the tree X, and record accesses to variables.  If X is written by the
1199    parent tree, WRITER is the parent.
1200    We store accesses in one of the two lists: PBEFORE_SP, and PNO_SP.  If this
1201    expression or its only operand forces a sequence point, then everything up
1202    to the sequence point is stored in PBEFORE_SP.  Everything else gets stored
1203    in PNO_SP.
1204    Once we return, we will have emitted warnings if any subexpression before
1205    such a sequence point could be undefined.  On a higher level, however, the
1206    sequence point may not be relevant, and we'll merge the two lists.
1207
1208    Example: (b++, a) + b;
1209    The call that processes the COMPOUND_EXPR will store the increment of B
1210    in PBEFORE_SP, and the use of A in PNO_SP.  The higher-level call that
1211    processes the PLUS_EXPR will need to merge the two lists so that
1212    eventually, all accesses end up on the same list (and we'll warn about the
1213    unordered subexpressions b++ and b.
1214
1215    A note on merging.  If we modify the former example so that our expression
1216    becomes
1217      (b++, b) + a
1218    care must be taken not simply to add all three expressions into the final
1219    PNO_SP list.  The function merge_tlist takes care of that by merging the
1220    before-SP list of the COMPOUND_EXPR into its after-SP list in a special
1221    way, so that no more than one access to B is recorded.  */
1222
1223 static void
1224 verify_tree (x, pbefore_sp, pno_sp, writer)
1225      tree x;
1226      struct tlist **pbefore_sp, **pno_sp;
1227      tree writer;
1228 {
1229   struct tlist *tmp_before, *tmp_nosp, *tmp_list2, *tmp_list3;
1230   enum tree_code code;
1231   char class;
1232
1233   /* X may be NULL if it is the operand of an empty statement expression
1234      ({ }).  */
1235   if (x == NULL)
1236     return;
1237
1238  restart:
1239   code = TREE_CODE (x);
1240   class = TREE_CODE_CLASS (code);
1241
1242   if (warning_candidate_p (x))
1243     {
1244       *pno_sp = new_tlist (*pno_sp, x, writer);
1245       return;
1246     }
1247
1248   switch (code)
1249     {
1250     case CONSTRUCTOR:
1251       return;
1252
1253     case COMPOUND_EXPR:
1254     case TRUTH_ANDIF_EXPR:
1255     case TRUTH_ORIF_EXPR:
1256       tmp_before = tmp_nosp = tmp_list3 = 0;
1257       verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE);
1258       warn_for_collisions (tmp_nosp);
1259       merge_tlist (pbefore_sp, tmp_before, 0);
1260       merge_tlist (pbefore_sp, tmp_nosp, 0);
1261       verify_tree (TREE_OPERAND (x, 1), &tmp_list3, pno_sp, NULL_TREE);
1262       merge_tlist (pbefore_sp, tmp_list3, 0);
1263       return;
1264
1265     case COND_EXPR:
1266       tmp_before = tmp_list2 = 0;
1267       verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_list2, NULL_TREE);
1268       warn_for_collisions (tmp_list2);
1269       merge_tlist (pbefore_sp, tmp_before, 0);
1270       merge_tlist (pbefore_sp, tmp_list2, 1);
1271
1272       tmp_list3 = tmp_nosp = 0;
1273       verify_tree (TREE_OPERAND (x, 1), &tmp_list3, &tmp_nosp, NULL_TREE);
1274       warn_for_collisions (tmp_nosp);
1275       merge_tlist (pbefore_sp, tmp_list3, 0);
1276
1277       tmp_list3 = tmp_list2 = 0;
1278       verify_tree (TREE_OPERAND (x, 2), &tmp_list3, &tmp_list2, NULL_TREE);
1279       warn_for_collisions (tmp_list2);
1280       merge_tlist (pbefore_sp, tmp_list3, 0);
1281       /* Rather than add both tmp_nosp and tmp_list2, we have to merge the
1282          two first, to avoid warning for (a ? b++ : b++).  */
1283       merge_tlist (&tmp_nosp, tmp_list2, 0);
1284       add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1285       return;
1286
1287     case PREDECREMENT_EXPR:
1288     case PREINCREMENT_EXPR:
1289     case POSTDECREMENT_EXPR:
1290     case POSTINCREMENT_EXPR:
1291       verify_tree (TREE_OPERAND (x, 0), pno_sp, pno_sp, x);
1292       return;
1293
1294     case MODIFY_EXPR:
1295       tmp_before = tmp_nosp = tmp_list3 = 0;
1296       verify_tree (TREE_OPERAND (x, 1), &tmp_before, &tmp_nosp, NULL_TREE);
1297       verify_tree (TREE_OPERAND (x, 0), &tmp_list3, &tmp_list3, x);
1298       /* Expressions inside the LHS are not ordered wrt. the sequence points
1299          in the RHS.  Example:
1300            *a = (a++, 2)
1301          Despite the fact that the modification of "a" is in the before_sp
1302          list (tmp_before), it conflicts with the use of "a" in the LHS.
1303          We can handle this by adding the contents of tmp_list3
1304          to those of tmp_before, and redoing the collision warnings for that
1305          list.  */
1306       add_tlist (&tmp_before, tmp_list3, x, 1);
1307       warn_for_collisions (tmp_before);
1308       /* Exclude the LHS itself here; we first have to merge it into the
1309          tmp_nosp list.  This is done to avoid warning for "a = a"; if we
1310          didn't exclude the LHS, we'd get it twice, once as a read and once
1311          as a write.  */
1312       add_tlist (pno_sp, tmp_list3, x, 0);
1313       warn_for_collisions_1 (TREE_OPERAND (x, 0), x, tmp_nosp, 1);
1314
1315       merge_tlist (pbefore_sp, tmp_before, 0);
1316       if (warning_candidate_p (TREE_OPERAND (x, 0)))
1317         merge_tlist (&tmp_nosp, new_tlist (NULL, TREE_OPERAND (x, 0), x), 0);
1318       add_tlist (pno_sp, tmp_nosp, NULL_TREE, 1);
1319       return;
1320
1321     case CALL_EXPR:
1322       /* We need to warn about conflicts among arguments and conflicts between
1323          args and the function address.  Side effects of the function address,
1324          however, are not ordered by the sequence point of the call.  */
1325       tmp_before = tmp_nosp = tmp_list2 = tmp_list3 = 0;
1326       verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE);
1327       if (TREE_OPERAND (x, 1))
1328         verify_tree (TREE_OPERAND (x, 1), &tmp_list2, &tmp_list3, NULL_TREE);
1329       merge_tlist (&tmp_list3, tmp_list2, 0);
1330       add_tlist (&tmp_before, tmp_list3, NULL_TREE, 0);
1331       add_tlist (&tmp_before, tmp_nosp, NULL_TREE, 0);
1332       warn_for_collisions (tmp_before);
1333       add_tlist (pbefore_sp, tmp_before, NULL_TREE, 0);
1334       return;
1335
1336     case TREE_LIST:
1337       /* Scan all the list, e.g. indices of multi dimensional array.  */
1338       while (x)
1339         {
1340           tmp_before = tmp_nosp = 0;
1341           verify_tree (TREE_VALUE (x), &tmp_before, &tmp_nosp, NULL_TREE);
1342           merge_tlist (&tmp_nosp, tmp_before, 0);
1343           add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1344           x = TREE_CHAIN (x);
1345         }
1346       return;
1347
1348     case SAVE_EXPR:
1349       {
1350         struct tlist_cache *t;
1351         for (t = save_expr_cache; t; t = t->next)
1352           if (t->expr == x)
1353             break;
1354
1355         if (! t)
1356           {
1357             t = (struct tlist_cache *) obstack_alloc (&tlist_obstack,
1358                                                       sizeof *t);
1359             t->next = save_expr_cache;
1360             t->expr = x;
1361             save_expr_cache = t;
1362
1363             tmp_before = tmp_nosp = 0;
1364             verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE);
1365             warn_for_collisions (tmp_nosp);
1366
1367             tmp_list3 = 0;
1368             while (tmp_nosp)
1369               {
1370                 struct tlist *t = tmp_nosp;
1371                 tmp_nosp = t->next;
1372                 merge_tlist (&tmp_list3, t, 0);
1373               }
1374             t->cache_before_sp = tmp_before;
1375             t->cache_after_sp = tmp_list3;
1376           }
1377         merge_tlist (pbefore_sp, t->cache_before_sp, 1);
1378         add_tlist (pno_sp, t->cache_after_sp, NULL_TREE, 1);
1379         return;
1380       }
1381     default:
1382       break;
1383     }
1384
1385   if (class == '1')
1386     {
1387       if (first_rtl_op (code) == 0)
1388         return;
1389       x = TREE_OPERAND (x, 0);
1390       writer = 0;
1391       goto restart;
1392     }
1393
1394   switch (class)
1395     {
1396     case 'r':
1397     case '<':
1398     case '2':
1399     case 'b':
1400     case 'e':
1401     case 's':
1402     case 'x':
1403       {
1404         int lp;
1405         int max = first_rtl_op (TREE_CODE (x));
1406         for (lp = 0; lp < max; lp++)
1407           {
1408             tmp_before = tmp_nosp = 0;
1409             verify_tree (TREE_OPERAND (x, lp), &tmp_before, &tmp_nosp, NULL_TREE);
1410             merge_tlist (&tmp_nosp, tmp_before, 0);
1411             add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1412           }
1413         break;
1414       }
1415     }
1416 }
1417
1418 /* Try to warn for undefined behaviour in EXPR due to missing sequence
1419    points.  */
1420
1421 static void
1422 verify_sequence_points (expr)
1423      tree expr;
1424 {
1425   struct tlist *before_sp = 0, *after_sp = 0;
1426
1427   warned_ids = 0;
1428   save_expr_cache = 0;
1429   if (tlist_firstobj == 0)
1430     {
1431       gcc_obstack_init (&tlist_obstack);
1432       tlist_firstobj = obstack_alloc (&tlist_obstack, 0);
1433     }
1434
1435   verify_tree (expr, &before_sp, &after_sp, 0);
1436   warn_for_collisions (after_sp);
1437   obstack_free (&tlist_obstack, tlist_firstobj);
1438 }
1439
1440 tree
1441 c_expand_expr_stmt (expr)
1442      tree expr;
1443 {
1444   /* Do default conversion if safe and possibly important,
1445      in case within ({...}).  */
1446   if ((TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE
1447        && (flag_isoc99 || lvalue_p (expr)))
1448       || TREE_CODE (TREE_TYPE (expr)) == FUNCTION_TYPE)
1449     expr = default_conversion (expr);
1450
1451   if (warn_sequence_point)
1452     verify_sequence_points (expr);
1453
1454   if (TREE_TYPE (expr) != error_mark_node
1455       && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
1456       && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
1457     error ("expression statement has incomplete type");
1458
1459   last_expr_type = TREE_TYPE (expr);
1460   return add_stmt (build_stmt (EXPR_STMT, expr));
1461 }
1462 \f
1463 /* Validate the expression after `case' and apply default promotions.  */
1464
1465 tree
1466 check_case_value (value)
1467      tree value;
1468 {
1469   if (value == NULL_TREE)
1470     return value;
1471
1472   /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue.  */
1473   STRIP_TYPE_NOPS (value);
1474   /* In C++, the following is allowed:
1475
1476        const int i = 3;
1477        switch (...) { case i: ... }
1478
1479      So, we try to reduce the VALUE to a constant that way.  */
1480   if (c_language == clk_cplusplus)
1481     {
1482       value = decl_constant_value (value);
1483       STRIP_TYPE_NOPS (value);
1484       value = fold (value);
1485     }
1486
1487   if (TREE_CODE (value) != INTEGER_CST
1488       && value != error_mark_node)
1489     {
1490       error ("case label does not reduce to an integer constant");
1491       value = error_mark_node;
1492     }
1493   else
1494     /* Promote char or short to int.  */
1495     value = default_conversion (value);
1496
1497   constant_expression_warning (value);
1498
1499   return value;
1500 }
1501 \f
1502 /* Return an integer type with BITS bits of precision,
1503    that is unsigned if UNSIGNEDP is nonzero, otherwise signed.  */
1504
1505 tree
1506 c_common_type_for_size (bits, unsignedp)
1507      unsigned bits;
1508      int unsignedp;
1509 {
1510   if (bits == TYPE_PRECISION (integer_type_node))
1511     return unsignedp ? unsigned_type_node : integer_type_node;
1512
1513   if (bits == TYPE_PRECISION (signed_char_type_node))
1514     return unsignedp ? unsigned_char_type_node : signed_char_type_node;
1515
1516   if (bits == TYPE_PRECISION (short_integer_type_node))
1517     return unsignedp ? short_unsigned_type_node : short_integer_type_node;
1518
1519   if (bits == TYPE_PRECISION (long_integer_type_node))
1520     return unsignedp ? long_unsigned_type_node : long_integer_type_node;
1521
1522   if (bits == TYPE_PRECISION (long_long_integer_type_node))
1523     return (unsignedp ? long_long_unsigned_type_node
1524             : long_long_integer_type_node);
1525
1526   if (bits == TYPE_PRECISION (widest_integer_literal_type_node))
1527     return (unsignedp ? widest_unsigned_literal_type_node
1528             : widest_integer_literal_type_node);
1529
1530   if (bits <= TYPE_PRECISION (intQI_type_node))
1531     return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
1532
1533   if (bits <= TYPE_PRECISION (intHI_type_node))
1534     return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
1535
1536   if (bits <= TYPE_PRECISION (intSI_type_node))
1537     return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
1538
1539   if (bits <= TYPE_PRECISION (intDI_type_node))
1540     return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
1541
1542   return 0;
1543 }
1544
1545 /* Return a data type that has machine mode MODE.
1546    If the mode is an integer,
1547    then UNSIGNEDP selects between signed and unsigned types.  */
1548
1549 tree
1550 c_common_type_for_mode (mode, unsignedp)
1551      enum machine_mode mode;
1552      int unsignedp;
1553 {
1554   if (mode == TYPE_MODE (integer_type_node))
1555     return unsignedp ? unsigned_type_node : integer_type_node;
1556
1557   if (mode == TYPE_MODE (signed_char_type_node))
1558     return unsignedp ? unsigned_char_type_node : signed_char_type_node;
1559
1560   if (mode == TYPE_MODE (short_integer_type_node))
1561     return unsignedp ? short_unsigned_type_node : short_integer_type_node;
1562
1563   if (mode == TYPE_MODE (long_integer_type_node))
1564     return unsignedp ? long_unsigned_type_node : long_integer_type_node;
1565
1566   if (mode == TYPE_MODE (long_long_integer_type_node))
1567     return unsignedp ? long_long_unsigned_type_node : long_long_integer_type_node;
1568
1569   if (mode == TYPE_MODE (widest_integer_literal_type_node))
1570     return unsignedp ? widest_unsigned_literal_type_node
1571                      : widest_integer_literal_type_node;
1572
1573   if (mode == QImode)
1574     return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
1575
1576   if (mode == HImode)
1577     return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
1578
1579   if (mode == SImode)
1580     return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
1581
1582   if (mode == DImode)
1583     return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
1584
1585 #if HOST_BITS_PER_WIDE_INT >= 64
1586   if (mode == TYPE_MODE (intTI_type_node))
1587     return unsignedp ? unsigned_intTI_type_node : intTI_type_node;
1588 #endif
1589
1590   if (mode == TYPE_MODE (float_type_node))
1591     return float_type_node;
1592
1593   if (mode == TYPE_MODE (double_type_node))
1594     return double_type_node;
1595
1596   if (mode == TYPE_MODE (long_double_type_node))
1597     return long_double_type_node;
1598
1599   if (mode == TYPE_MODE (build_pointer_type (char_type_node)))
1600     return build_pointer_type (char_type_node);
1601
1602   if (mode == TYPE_MODE (build_pointer_type (integer_type_node)))
1603     return build_pointer_type (integer_type_node);
1604
1605   switch (mode)
1606     {
1607     case V16QImode:
1608       return unsignedp ? unsigned_V16QI_type_node : V16QI_type_node;
1609     case V8HImode:
1610       return unsignedp ? unsigned_V8HI_type_node : V8HI_type_node;
1611     case V4SImode:
1612       return unsignedp ? unsigned_V4SI_type_node : V4SI_type_node;
1613     case V2DImode:
1614       return unsignedp ? unsigned_V2DI_type_node : V2DI_type_node;
1615     case V2SImode:
1616       return unsignedp ? unsigned_V2SI_type_node : V2SI_type_node;
1617     case V4HImode:
1618       return unsignedp ? unsigned_V4HI_type_node : V4HI_type_node;
1619     case V8QImode:
1620       return unsignedp ? unsigned_V8QI_type_node : V8QI_type_node;
1621     case V16SFmode:
1622       return V16SF_type_node;
1623     case V4SFmode:
1624       return V4SF_type_node;
1625     case V2SFmode:
1626       return V2SF_type_node;
1627     case V2DFmode:
1628       return V2DF_type_node;
1629     default:
1630       break;
1631     }
1632
1633   return 0;
1634 }
1635
1636 /* Return an unsigned type the same as TYPE in other respects.  */
1637 tree
1638 c_common_unsigned_type (type)
1639      tree type;
1640 {
1641   tree type1 = TYPE_MAIN_VARIANT (type);
1642   if (type1 == signed_char_type_node || type1 == char_type_node)
1643     return unsigned_char_type_node;
1644   if (type1 == integer_type_node)
1645     return unsigned_type_node;
1646   if (type1 == short_integer_type_node)
1647     return short_unsigned_type_node;
1648   if (type1 == long_integer_type_node)
1649     return long_unsigned_type_node;
1650   if (type1 == long_long_integer_type_node)
1651     return long_long_unsigned_type_node;
1652   if (type1 == widest_integer_literal_type_node)
1653     return widest_unsigned_literal_type_node;
1654 #if HOST_BITS_PER_WIDE_INT >= 64
1655   if (type1 == intTI_type_node)
1656     return unsigned_intTI_type_node;
1657 #endif
1658   if (type1 == intDI_type_node)
1659     return unsigned_intDI_type_node;
1660   if (type1 == intSI_type_node)
1661     return unsigned_intSI_type_node;
1662   if (type1 == intHI_type_node)
1663     return unsigned_intHI_type_node;
1664   if (type1 == intQI_type_node)
1665     return unsigned_intQI_type_node;
1666
1667   return c_common_signed_or_unsigned_type (1, type);
1668 }
1669
1670 /* Return a signed type the same as TYPE in other respects.  */
1671
1672 tree
1673 c_common_signed_type (type)
1674      tree type;
1675 {
1676   tree type1 = TYPE_MAIN_VARIANT (type);
1677   if (type1 == unsigned_char_type_node || type1 == char_type_node)
1678     return signed_char_type_node;
1679   if (type1 == unsigned_type_node)
1680     return integer_type_node;
1681   if (type1 == short_unsigned_type_node)
1682     return short_integer_type_node;
1683   if (type1 == long_unsigned_type_node)
1684     return long_integer_type_node;
1685   if (type1 == long_long_unsigned_type_node)
1686     return long_long_integer_type_node;
1687   if (type1 == widest_unsigned_literal_type_node)
1688     return widest_integer_literal_type_node;
1689 #if HOST_BITS_PER_WIDE_INT >= 64
1690   if (type1 == unsigned_intTI_type_node)
1691     return intTI_type_node;
1692 #endif
1693   if (type1 == unsigned_intDI_type_node)
1694     return intDI_type_node;
1695   if (type1 == unsigned_intSI_type_node)
1696     return intSI_type_node;
1697   if (type1 == unsigned_intHI_type_node)
1698     return intHI_type_node;
1699   if (type1 == unsigned_intQI_type_node)
1700     return intQI_type_node;
1701
1702   return c_common_signed_or_unsigned_type (0, type);
1703 }
1704
1705 /* Return a type the same as TYPE except unsigned or
1706    signed according to UNSIGNEDP.  */
1707
1708 tree
1709 c_common_signed_or_unsigned_type (unsignedp, type)
1710      int unsignedp;
1711      tree type;
1712 {
1713   if (! INTEGRAL_TYPE_P (type)
1714       || TREE_UNSIGNED (type) == unsignedp)
1715     return type;
1716
1717   if (TYPE_PRECISION (type) == TYPE_PRECISION (signed_char_type_node))
1718     return unsignedp ? unsigned_char_type_node : signed_char_type_node;
1719   if (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1720     return unsignedp ? unsigned_type_node : integer_type_node;
1721   if (TYPE_PRECISION (type) == TYPE_PRECISION (short_integer_type_node))
1722     return unsignedp ? short_unsigned_type_node : short_integer_type_node;
1723   if (TYPE_PRECISION (type) == TYPE_PRECISION (long_integer_type_node))
1724     return unsignedp ? long_unsigned_type_node : long_integer_type_node;
1725   if (TYPE_PRECISION (type) == TYPE_PRECISION (long_long_integer_type_node))
1726     return (unsignedp ? long_long_unsigned_type_node
1727             : long_long_integer_type_node);
1728   if (TYPE_PRECISION (type) == TYPE_PRECISION (widest_integer_literal_type_node))
1729     return (unsignedp ? widest_unsigned_literal_type_node
1730             : widest_integer_literal_type_node);
1731
1732 #if HOST_BITS_PER_WIDE_INT >= 64
1733   if (TYPE_PRECISION (type) == TYPE_PRECISION (intTI_type_node))
1734     return unsignedp ? unsigned_intTI_type_node : intTI_type_node;
1735 #endif
1736   if (TYPE_PRECISION (type) == TYPE_PRECISION (intDI_type_node))
1737     return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
1738   if (TYPE_PRECISION (type) == TYPE_PRECISION (intSI_type_node))
1739     return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
1740   if (TYPE_PRECISION (type) == TYPE_PRECISION (intHI_type_node))
1741     return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
1742   if (TYPE_PRECISION (type) == TYPE_PRECISION (intQI_type_node))
1743     return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
1744
1745   return type;
1746 }
1747 \f
1748 /* Return the minimum number of bits needed to represent VALUE in a
1749    signed or unsigned type, UNSIGNEDP says which.  */
1750
1751 unsigned int
1752 min_precision (value, unsignedp)
1753      tree value;
1754      int unsignedp;
1755 {
1756   int log;
1757
1758   /* If the value is negative, compute its negative minus 1.  The latter
1759      adjustment is because the absolute value of the largest negative value
1760      is one larger than the largest positive value.  This is equivalent to
1761      a bit-wise negation, so use that operation instead.  */
1762
1763   if (tree_int_cst_sgn (value) < 0)
1764     value = fold (build1 (BIT_NOT_EXPR, TREE_TYPE (value), value));
1765
1766   /* Return the number of bits needed, taking into account the fact
1767      that we need one more bit for a signed than unsigned type.  */
1768
1769   if (integer_zerop (value))
1770     log = 0;
1771   else
1772     log = tree_floor_log2 (value);
1773
1774   return log + 1 + ! unsignedp;
1775 }
1776 \f
1777 /* Print an error message for invalid operands to arith operation
1778    CODE.  NOP_EXPR is used as a special case (see
1779    c_common_truthvalue_conversion).  */
1780
1781 void
1782 binary_op_error (code)
1783      enum tree_code code;
1784 {
1785   const char *opname;
1786
1787   switch (code)
1788     {
1789     case NOP_EXPR:
1790       error ("invalid truth-value expression");
1791       return;
1792
1793     case PLUS_EXPR:
1794       opname = "+"; break;
1795     case MINUS_EXPR:
1796       opname = "-"; break;
1797     case MULT_EXPR:
1798       opname = "*"; break;
1799     case MAX_EXPR:
1800       opname = "max"; break;
1801     case MIN_EXPR:
1802       opname = "min"; break;
1803     case EQ_EXPR:
1804       opname = "=="; break;
1805     case NE_EXPR:
1806       opname = "!="; break;
1807     case LE_EXPR:
1808       opname = "<="; break;
1809     case GE_EXPR:
1810       opname = ">="; break;
1811     case LT_EXPR:
1812       opname = "<"; break;
1813     case GT_EXPR:
1814       opname = ">"; break;
1815     case LSHIFT_EXPR:
1816       opname = "<<"; break;
1817     case RSHIFT_EXPR:
1818       opname = ">>"; break;
1819     case TRUNC_MOD_EXPR:
1820     case FLOOR_MOD_EXPR:
1821       opname = "%"; break;
1822     case TRUNC_DIV_EXPR:
1823     case FLOOR_DIV_EXPR:
1824       opname = "/"; break;
1825     case BIT_AND_EXPR:
1826       opname = "&"; break;
1827     case BIT_IOR_EXPR:
1828       opname = "|"; break;
1829     case TRUTH_ANDIF_EXPR:
1830       opname = "&&"; break;
1831     case TRUTH_ORIF_EXPR:
1832       opname = "||"; break;
1833     case BIT_XOR_EXPR:
1834       opname = "^"; break;
1835     case LROTATE_EXPR:
1836     case RROTATE_EXPR:
1837       opname = "rotate"; break;
1838     default:
1839       opname = "unknown"; break;
1840     }
1841   error ("invalid operands to binary %s", opname);
1842 }
1843 \f
1844 /* Subroutine of build_binary_op, used for comparison operations.
1845    See if the operands have both been converted from subword integer types
1846    and, if so, perhaps change them both back to their original type.
1847    This function is also responsible for converting the two operands
1848    to the proper common type for comparison.
1849
1850    The arguments of this function are all pointers to local variables
1851    of build_binary_op: OP0_PTR is &OP0, OP1_PTR is &OP1,
1852    RESTYPE_PTR is &RESULT_TYPE and RESCODE_PTR is &RESULTCODE.
1853
1854    If this function returns nonzero, it means that the comparison has
1855    a constant value.  What this function returns is an expression for
1856    that value.  */
1857
1858 tree
1859 shorten_compare (op0_ptr, op1_ptr, restype_ptr, rescode_ptr)
1860      tree *op0_ptr, *op1_ptr;
1861      tree *restype_ptr;
1862      enum tree_code *rescode_ptr;
1863 {
1864   tree type;
1865   tree op0 = *op0_ptr;
1866   tree op1 = *op1_ptr;
1867   int unsignedp0, unsignedp1;
1868   int real1, real2;
1869   tree primop0, primop1;
1870   enum tree_code code = *rescode_ptr;
1871
1872   /* Throw away any conversions to wider types
1873      already present in the operands.  */
1874
1875   primop0 = get_narrower (op0, &unsignedp0);
1876   primop1 = get_narrower (op1, &unsignedp1);
1877
1878   /* Handle the case that OP0 does not *contain* a conversion
1879      but it *requires* conversion to FINAL_TYPE.  */
1880
1881   if (op0 == primop0 && TREE_TYPE (op0) != *restype_ptr)
1882     unsignedp0 = TREE_UNSIGNED (TREE_TYPE (op0));
1883   if (op1 == primop1 && TREE_TYPE (op1) != *restype_ptr)
1884     unsignedp1 = TREE_UNSIGNED (TREE_TYPE (op1));
1885
1886   /* If one of the operands must be floated, we cannot optimize.  */
1887   real1 = TREE_CODE (TREE_TYPE (primop0)) == REAL_TYPE;
1888   real2 = TREE_CODE (TREE_TYPE (primop1)) == REAL_TYPE;
1889
1890   /* If first arg is constant, swap the args (changing operation
1891      so value is preserved), for canonicalization.  Don't do this if
1892      the second arg is 0.  */
1893
1894   if (TREE_CONSTANT (primop0)
1895       && ! integer_zerop (primop1) && ! real_zerop (primop1))
1896     {
1897       tree tem = primop0;
1898       int temi = unsignedp0;
1899       primop0 = primop1;
1900       primop1 = tem;
1901       tem = op0;
1902       op0 = op1;
1903       op1 = tem;
1904       *op0_ptr = op0;
1905       *op1_ptr = op1;
1906       unsignedp0 = unsignedp1;
1907       unsignedp1 = temi;
1908       temi = real1;
1909       real1 = real2;
1910       real2 = temi;
1911
1912       switch (code)
1913         {
1914         case LT_EXPR:
1915           code = GT_EXPR;
1916           break;
1917         case GT_EXPR:
1918           code = LT_EXPR;
1919           break;
1920         case LE_EXPR:
1921           code = GE_EXPR;
1922           break;
1923         case GE_EXPR:
1924           code = LE_EXPR;
1925           break;
1926         default:
1927           break;
1928         }
1929       *rescode_ptr = code;
1930     }
1931
1932   /* If comparing an integer against a constant more bits wide,
1933      maybe we can deduce a value of 1 or 0 independent of the data.
1934      Or else truncate the constant now
1935      rather than extend the variable at run time.
1936
1937      This is only interesting if the constant is the wider arg.
1938      Also, it is not safe if the constant is unsigned and the
1939      variable arg is signed, since in this case the variable
1940      would be sign-extended and then regarded as unsigned.
1941      Our technique fails in this case because the lowest/highest
1942      possible unsigned results don't follow naturally from the
1943      lowest/highest possible values of the variable operand.
1944      For just EQ_EXPR and NE_EXPR there is another technique that
1945      could be used: see if the constant can be faithfully represented
1946      in the other operand's type, by truncating it and reextending it
1947      and see if that preserves the constant's value.  */
1948
1949   if (!real1 && !real2
1950       && TREE_CODE (primop1) == INTEGER_CST
1951       && TYPE_PRECISION (TREE_TYPE (primop0)) < TYPE_PRECISION (*restype_ptr))
1952     {
1953       int min_gt, max_gt, min_lt, max_lt;
1954       tree maxval, minval;
1955       /* 1 if comparison is nominally unsigned.  */
1956       int unsignedp = TREE_UNSIGNED (*restype_ptr);
1957       tree val;
1958
1959       type = c_common_signed_or_unsigned_type (unsignedp0,
1960                                                TREE_TYPE (primop0));
1961
1962       /* If TYPE is an enumeration, then we need to get its min/max
1963          values from it's underlying integral type, not the enumerated
1964          type itself.  */
1965       if (TREE_CODE (type) == ENUMERAL_TYPE)
1966         type = c_common_type_for_size (TYPE_PRECISION (type), unsignedp0);
1967
1968       maxval = TYPE_MAX_VALUE (type);
1969       minval = TYPE_MIN_VALUE (type);
1970
1971       if (unsignedp && !unsignedp0)
1972         *restype_ptr = c_common_signed_type (*restype_ptr);
1973
1974       if (TREE_TYPE (primop1) != *restype_ptr)
1975         primop1 = convert (*restype_ptr, primop1);
1976       if (type != *restype_ptr)
1977         {
1978           minval = convert (*restype_ptr, minval);
1979           maxval = convert (*restype_ptr, maxval);
1980         }
1981
1982       if (unsignedp && unsignedp0)
1983         {
1984           min_gt = INT_CST_LT_UNSIGNED (primop1, minval);
1985           max_gt = INT_CST_LT_UNSIGNED (primop1, maxval);
1986           min_lt = INT_CST_LT_UNSIGNED (minval, primop1);
1987           max_lt = INT_CST_LT_UNSIGNED (maxval, primop1);
1988         }
1989       else
1990         {
1991           min_gt = INT_CST_LT (primop1, minval);
1992           max_gt = INT_CST_LT (primop1, maxval);
1993           min_lt = INT_CST_LT (minval, primop1);
1994           max_lt = INT_CST_LT (maxval, primop1);
1995         }
1996
1997       val = 0;
1998       /* This used to be a switch, but Genix compiler can't handle that.  */
1999       if (code == NE_EXPR)
2000         {
2001           if (max_lt || min_gt)
2002             val = boolean_true_node;
2003         }
2004       else if (code == EQ_EXPR)
2005         {
2006           if (max_lt || min_gt)
2007             val = boolean_false_node;
2008         }
2009       else if (code == LT_EXPR)
2010         {
2011           if (max_lt)
2012             val = boolean_true_node;
2013           if (!min_lt)
2014             val = boolean_false_node;
2015         }
2016       else if (code == GT_EXPR)
2017         {
2018           if (min_gt)
2019             val = boolean_true_node;
2020           if (!max_gt)
2021             val = boolean_false_node;
2022         }
2023       else if (code == LE_EXPR)
2024         {
2025           if (!max_gt)
2026             val = boolean_true_node;
2027           if (min_gt)
2028             val = boolean_false_node;
2029         }
2030       else if (code == GE_EXPR)
2031         {
2032           if (!min_lt)
2033             val = boolean_true_node;
2034           if (max_lt)
2035             val = boolean_false_node;
2036         }
2037
2038       /* If primop0 was sign-extended and unsigned comparison specd,
2039          we did a signed comparison above using the signed type bounds.
2040          But the comparison we output must be unsigned.
2041
2042          Also, for inequalities, VAL is no good; but if the signed
2043          comparison had *any* fixed result, it follows that the
2044          unsigned comparison just tests the sign in reverse
2045          (positive values are LE, negative ones GE).
2046          So we can generate an unsigned comparison
2047          against an extreme value of the signed type.  */
2048
2049       if (unsignedp && !unsignedp0)
2050         {
2051           if (val != 0)
2052             switch (code)
2053               {
2054               case LT_EXPR:
2055               case GE_EXPR:
2056                 primop1 = TYPE_MIN_VALUE (type);
2057                 val = 0;
2058                 break;
2059
2060               case LE_EXPR:
2061               case GT_EXPR:
2062                 primop1 = TYPE_MAX_VALUE (type);
2063                 val = 0;
2064                 break;
2065
2066               default:
2067                 break;
2068               }
2069           type = c_common_unsigned_type (type);
2070         }
2071
2072       if (TREE_CODE (primop0) != INTEGER_CST)
2073         {
2074           if (val == boolean_false_node)
2075             warning ("comparison is always false due to limited range of data type");
2076           if (val == boolean_true_node)
2077             warning ("comparison is always true due to limited range of data type");
2078         }
2079
2080       if (val != 0)
2081         {
2082           /* Don't forget to evaluate PRIMOP0 if it has side effects.  */
2083           if (TREE_SIDE_EFFECTS (primop0))
2084             return build (COMPOUND_EXPR, TREE_TYPE (val), primop0, val);
2085           return val;
2086         }
2087
2088       /* Value is not predetermined, but do the comparison
2089          in the type of the operand that is not constant.
2090          TYPE is already properly set.  */
2091     }
2092   else if (real1 && real2
2093            && (TYPE_PRECISION (TREE_TYPE (primop0))
2094                == TYPE_PRECISION (TREE_TYPE (primop1))))
2095     type = TREE_TYPE (primop0);
2096
2097   /* If args' natural types are both narrower than nominal type
2098      and both extend in the same manner, compare them
2099      in the type of the wider arg.
2100      Otherwise must actually extend both to the nominal
2101      common type lest different ways of extending
2102      alter the result.
2103      (eg, (short)-1 == (unsigned short)-1  should be 0.)  */
2104
2105   else if (unsignedp0 == unsignedp1 && real1 == real2
2106            && TYPE_PRECISION (TREE_TYPE (primop0)) < TYPE_PRECISION (*restype_ptr)
2107            && TYPE_PRECISION (TREE_TYPE (primop1)) < TYPE_PRECISION (*restype_ptr))
2108     {
2109       type = common_type (TREE_TYPE (primop0), TREE_TYPE (primop1));
2110       type = c_common_signed_or_unsigned_type (unsignedp0
2111                                                || TREE_UNSIGNED (*restype_ptr),
2112                                                type);
2113       /* Make sure shorter operand is extended the right way
2114          to match the longer operand.  */
2115       primop0
2116         = convert (c_common_signed_or_unsigned_type (unsignedp0,
2117                                                      TREE_TYPE (primop0)),
2118                    primop0);
2119       primop1
2120         = convert (c_common_signed_or_unsigned_type (unsignedp1,
2121                                                      TREE_TYPE (primop1)),
2122                    primop1);
2123     }
2124   else
2125     {
2126       /* Here we must do the comparison on the nominal type
2127          using the args exactly as we received them.  */
2128       type = *restype_ptr;
2129       primop0 = op0;
2130       primop1 = op1;
2131
2132       if (!real1 && !real2 && integer_zerop (primop1)
2133           && TREE_UNSIGNED (*restype_ptr))
2134         {
2135           tree value = 0;
2136           switch (code)
2137             {
2138             case GE_EXPR:
2139               /* All unsigned values are >= 0, so we warn if extra warnings
2140                  are requested.  However, if OP0 is a constant that is
2141                  >= 0, the signedness of the comparison isn't an issue,
2142                  so suppress the warning.  */
2143               if (extra_warnings && !in_system_header
2144                   && ! (TREE_CODE (primop0) == INTEGER_CST
2145                         && ! TREE_OVERFLOW (convert (c_common_signed_type (type),
2146                                                      primop0))))
2147                 warning ("comparison of unsigned expression >= 0 is always true");
2148               value = boolean_true_node;
2149               break;
2150
2151             case LT_EXPR:
2152               if (extra_warnings && !in_system_header
2153                   && ! (TREE_CODE (primop0) == INTEGER_CST
2154                         && ! TREE_OVERFLOW (convert (c_common_signed_type (type),
2155                                                      primop0))))
2156                 warning ("comparison of unsigned expression < 0 is always false");
2157               value = boolean_false_node;
2158               break;
2159
2160             default:
2161               break;
2162             }
2163
2164           if (value != 0)
2165             {
2166               /* Don't forget to evaluate PRIMOP0 if it has side effects.  */
2167               if (TREE_SIDE_EFFECTS (primop0))
2168                 return build (COMPOUND_EXPR, TREE_TYPE (value),
2169                               primop0, value);
2170               return value;
2171             }
2172         }
2173     }
2174
2175   *op0_ptr = convert (type, primop0);
2176   *op1_ptr = convert (type, primop1);
2177
2178   *restype_ptr = boolean_type_node;
2179
2180   return 0;
2181 }
2182 \f
2183 /* Return a tree for the sum or difference (RESULTCODE says which)
2184    of pointer PTROP and integer INTOP.  */
2185
2186 tree
2187 pointer_int_sum (resultcode, ptrop, intop)
2188      enum tree_code resultcode;
2189      tree ptrop, intop;
2190 {
2191   tree size_exp;
2192
2193   tree result;
2194   tree folded;
2195
2196   /* The result is a pointer of the same type that is being added.  */
2197
2198   tree result_type = TREE_TYPE (ptrop);
2199
2200   if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)
2201     {
2202       if (pedantic || warn_pointer_arith)
2203         pedwarn ("pointer of type `void *' used in arithmetic");
2204       size_exp = integer_one_node;
2205     }
2206   else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE)
2207     {
2208       if (pedantic || warn_pointer_arith)
2209         pedwarn ("pointer to a function used in arithmetic");
2210       size_exp = integer_one_node;
2211     }
2212   else if (TREE_CODE (TREE_TYPE (result_type)) == METHOD_TYPE)
2213     {
2214       if (pedantic || warn_pointer_arith)
2215         pedwarn ("pointer to member function used in arithmetic");
2216       size_exp = integer_one_node;
2217     }
2218   else if (TREE_CODE (TREE_TYPE (result_type)) == OFFSET_TYPE)
2219     {
2220       if (pedantic || warn_pointer_arith)
2221         pedwarn ("pointer to a member used in arithmetic");
2222       size_exp = integer_one_node;
2223     }
2224   else
2225     size_exp = size_in_bytes (TREE_TYPE (result_type));
2226
2227   /* If what we are about to multiply by the size of the elements
2228      contains a constant term, apply distributive law
2229      and multiply that constant term separately.
2230      This helps produce common subexpressions.  */
2231
2232   if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR)
2233       && ! TREE_CONSTANT (intop)
2234       && TREE_CONSTANT (TREE_OPERAND (intop, 1))
2235       && TREE_CONSTANT (size_exp)
2236       /* If the constant comes from pointer subtraction,
2237          skip this optimization--it would cause an error.  */
2238       && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE
2239       /* If the constant is unsigned, and smaller than the pointer size,
2240          then we must skip this optimization.  This is because it could cause
2241          an overflow error if the constant is negative but INTOP is not.  */
2242       && (! TREE_UNSIGNED (TREE_TYPE (intop))
2243           || (TYPE_PRECISION (TREE_TYPE (intop))
2244               == TYPE_PRECISION (TREE_TYPE (ptrop)))))
2245     {
2246       enum tree_code subcode = resultcode;
2247       tree int_type = TREE_TYPE (intop);
2248       if (TREE_CODE (intop) == MINUS_EXPR)
2249         subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR);
2250       /* Convert both subexpression types to the type of intop,
2251          because weird cases involving pointer arithmetic
2252          can result in a sum or difference with different type args.  */
2253       ptrop = build_binary_op (subcode, ptrop,
2254                                convert (int_type, TREE_OPERAND (intop, 1)), 1);
2255       intop = convert (int_type, TREE_OPERAND (intop, 0));
2256     }
2257
2258   /* Convert the integer argument to a type the same size as sizetype
2259      so the multiply won't overflow spuriously.  */
2260
2261   if (TYPE_PRECISION (TREE_TYPE (intop)) != TYPE_PRECISION (sizetype)
2262       || TREE_UNSIGNED (TREE_TYPE (intop)) != TREE_UNSIGNED (sizetype))
2263     intop = convert (c_common_type_for_size (TYPE_PRECISION (sizetype),
2264                                              TREE_UNSIGNED (sizetype)), intop);
2265
2266   /* Replace the integer argument with a suitable product by the object size.
2267      Do this multiplication as signed, then convert to the appropriate
2268      pointer type (actually unsigned integral).  */
2269
2270   intop = convert (result_type,
2271                    build_binary_op (MULT_EXPR, intop,
2272                                     convert (TREE_TYPE (intop), size_exp), 1));
2273
2274   /* Create the sum or difference.  */
2275
2276   result = build (resultcode, result_type, ptrop, intop);
2277
2278   folded = fold (result);
2279   if (folded == result)
2280     TREE_CONSTANT (folded) = TREE_CONSTANT (ptrop) & TREE_CONSTANT (intop);
2281   return folded;
2282 }
2283 \f
2284 /* Prepare expr to be an argument of a TRUTH_NOT_EXPR,
2285    or validate its data type for an `if' or `while' statement or ?..: exp.
2286
2287    This preparation consists of taking the ordinary
2288    representation of an expression expr and producing a valid tree
2289    boolean expression describing whether expr is nonzero.  We could
2290    simply always do build_binary_op (NE_EXPR, expr, boolean_false_node, 1),
2291    but we optimize comparisons, &&, ||, and !.
2292
2293    The resulting type should always be `boolean_type_node'.  */
2294
2295 tree
2296 c_common_truthvalue_conversion (expr)
2297      tree expr;
2298 {
2299   if (TREE_CODE (expr) == ERROR_MARK)
2300     return expr;
2301
2302 #if 0 /* This appears to be wrong for C++.  */
2303   /* These really should return error_mark_node after 2.4 is stable.
2304      But not all callers handle ERROR_MARK properly.  */
2305   switch (TREE_CODE (TREE_TYPE (expr)))
2306     {
2307     case RECORD_TYPE:
2308       error ("struct type value used where scalar is required");
2309       return boolean_false_node;
2310
2311     case UNION_TYPE:
2312       error ("union type value used where scalar is required");
2313       return boolean_false_node;
2314
2315     case ARRAY_TYPE:
2316       error ("array type value used where scalar is required");
2317       return boolean_false_node;
2318
2319     default:
2320       break;
2321     }
2322 #endif /* 0 */
2323
2324   switch (TREE_CODE (expr))
2325     {
2326     case EQ_EXPR:
2327     case NE_EXPR: case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2328     case TRUTH_ANDIF_EXPR:
2329     case TRUTH_ORIF_EXPR:
2330     case TRUTH_AND_EXPR:
2331     case TRUTH_OR_EXPR:
2332     case TRUTH_XOR_EXPR:
2333     case TRUTH_NOT_EXPR:
2334       TREE_TYPE (expr) = boolean_type_node;
2335       return expr;
2336
2337     case ERROR_MARK:
2338       return expr;
2339
2340     case INTEGER_CST:
2341       return integer_zerop (expr) ? boolean_false_node : boolean_true_node;
2342
2343     case REAL_CST:
2344       return real_zerop (expr) ? boolean_false_node : boolean_true_node;
2345
2346     case ADDR_EXPR:
2347       /* If we are taking the address of an external decl, it might be zero
2348          if it is weak, so we cannot optimize.  */
2349       if (DECL_P (TREE_OPERAND (expr, 0))
2350           && DECL_EXTERNAL (TREE_OPERAND (expr, 0)))
2351         break;
2352
2353       if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 0)))
2354         return build (COMPOUND_EXPR, boolean_type_node,
2355                       TREE_OPERAND (expr, 0), boolean_true_node);
2356       else
2357         return boolean_true_node;
2358
2359     case COMPLEX_EXPR:
2360       return build_binary_op ((TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1))
2361                                ? TRUTH_OR_EXPR : TRUTH_ORIF_EXPR),
2362                 c_common_truthvalue_conversion (TREE_OPERAND (expr, 0)),
2363                 c_common_truthvalue_conversion (TREE_OPERAND (expr, 1)),
2364                               0);
2365
2366     case NEGATE_EXPR:
2367     case ABS_EXPR:
2368     case FLOAT_EXPR:
2369     case FFS_EXPR:
2370       /* These don't change whether an object is non-zero or zero.  */
2371       return c_common_truthvalue_conversion (TREE_OPERAND (expr, 0));
2372
2373     case LROTATE_EXPR:
2374     case RROTATE_EXPR:
2375       /* These don't change whether an object is zero or non-zero, but
2376          we can't ignore them if their second arg has side-effects.  */
2377       if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
2378         return build (COMPOUND_EXPR, boolean_type_node, TREE_OPERAND (expr, 1),
2379                       c_common_truthvalue_conversion (TREE_OPERAND (expr, 0)));
2380       else
2381         return c_common_truthvalue_conversion (TREE_OPERAND (expr, 0));
2382
2383     case COND_EXPR:
2384       /* Distribute the conversion into the arms of a COND_EXPR.  */
2385       return fold (build (COND_EXPR, boolean_type_node, TREE_OPERAND (expr, 0),
2386                 c_common_truthvalue_conversion (TREE_OPERAND (expr, 1)),
2387                 c_common_truthvalue_conversion (TREE_OPERAND (expr, 2))));
2388
2389     case CONVERT_EXPR:
2390       /* Don't cancel the effect of a CONVERT_EXPR from a REFERENCE_TYPE,
2391          since that affects how `default_conversion' will behave.  */
2392       if (TREE_CODE (TREE_TYPE (expr)) == REFERENCE_TYPE
2393           || TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == REFERENCE_TYPE)
2394         break;
2395       /* fall through...  */
2396     case NOP_EXPR:
2397       /* If this is widening the argument, we can ignore it.  */
2398       if (TYPE_PRECISION (TREE_TYPE (expr))
2399           >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (expr, 0))))
2400         return c_common_truthvalue_conversion (TREE_OPERAND (expr, 0));
2401       break;
2402
2403     case MINUS_EXPR:
2404       /* Perhaps reduce (x - y) != 0 to (x != y).  The expressions
2405          aren't guaranteed to the be same for modes that can represent
2406          infinity, since if x and y are both +infinity, or both
2407          -infinity, then x - y is not a number.
2408
2409          Note that this transformation is safe when x or y is NaN.
2410          (x - y) is then NaN, and both (x - y) != 0 and x != y will
2411          be false.  */
2412       if (HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (TREE_OPERAND (expr, 0)))))
2413         break;
2414       /* fall through...  */
2415     case BIT_XOR_EXPR:
2416       /* This and MINUS_EXPR can be changed into a comparison of the
2417          two objects.  */
2418       if (TREE_TYPE (TREE_OPERAND (expr, 0))
2419           == TREE_TYPE (TREE_OPERAND (expr, 1)))
2420         return build_binary_op (NE_EXPR, TREE_OPERAND (expr, 0),
2421                                 TREE_OPERAND (expr, 1), 1);
2422       return build_binary_op (NE_EXPR, TREE_OPERAND (expr, 0),
2423                               fold (build1 (NOP_EXPR,
2424                                             TREE_TYPE (TREE_OPERAND (expr, 0)),
2425                                             TREE_OPERAND (expr, 1))), 1);
2426
2427     case BIT_AND_EXPR:
2428       if (integer_onep (TREE_OPERAND (expr, 1))
2429           && TREE_TYPE (expr) != boolean_type_node)
2430         /* Using convert here would cause infinite recursion.  */
2431         return build1 (NOP_EXPR, boolean_type_node, expr);
2432       break;
2433
2434     case MODIFY_EXPR:
2435       if (warn_parentheses && C_EXP_ORIGINAL_CODE (expr) == MODIFY_EXPR)
2436         warning ("suggest parentheses around assignment used as truth value");
2437       break;
2438
2439     default:
2440       break;
2441     }
2442
2443   if (TREE_CODE (TREE_TYPE (expr)) == COMPLEX_TYPE)
2444     {
2445       tree t = save_expr (expr);
2446       return (build_binary_op
2447               ((TREE_SIDE_EFFECTS (expr)
2448                 ? TRUTH_OR_EXPR : TRUTH_ORIF_EXPR),
2449         c_common_truthvalue_conversion (build_unary_op (REALPART_EXPR, t, 0)),
2450         c_common_truthvalue_conversion (build_unary_op (IMAGPART_EXPR, t, 0)),
2451                0));
2452     }
2453
2454   return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
2455 }
2456 \f
2457 static tree builtin_function_2 PARAMS ((const char *, const char *, tree, tree,
2458                                         int, enum built_in_class, int, int,
2459                                         tree));
2460
2461 /* Make a variant type in the proper way for C/C++, propagating qualifiers
2462    down to the element type of an array.  */
2463
2464 tree
2465 c_build_qualified_type (type, type_quals)
2466      tree type;
2467      int type_quals;
2468 {
2469   /* A restrict-qualified pointer type must be a pointer to object or
2470      incomplete type.  Note that the use of POINTER_TYPE_P also allows
2471      REFERENCE_TYPEs, which is appropriate for C++.  Unfortunately,
2472      the C++ front-end also use POINTER_TYPE for pointer-to-member
2473      values, so even though it should be illegal to use `restrict'
2474      with such an entity we don't flag that here.  Thus, special case
2475      code for that case is required in the C++ front-end.  */
2476   if ((type_quals & TYPE_QUAL_RESTRICT)
2477       && (!POINTER_TYPE_P (type)
2478           || !C_TYPE_OBJECT_OR_INCOMPLETE_P (TREE_TYPE (type))))
2479     {
2480       error ("invalid use of `restrict'");
2481       type_quals &= ~TYPE_QUAL_RESTRICT;
2482     }
2483
2484   if (TREE_CODE (type) == ARRAY_TYPE)
2485     return build_array_type (c_build_qualified_type (TREE_TYPE (type),
2486                                                      type_quals),
2487                              TYPE_DOMAIN (type));
2488   return build_qualified_type (type, type_quals);
2489 }
2490
2491 /* Apply the TYPE_QUALS to the new DECL.  */
2492
2493 void
2494 c_apply_type_quals_to_decl (type_quals, decl)
2495      int type_quals;
2496      tree decl;
2497 {
2498   if ((type_quals & TYPE_QUAL_CONST)
2499       || (TREE_TYPE (decl)
2500           && TREE_CODE (TREE_TYPE (decl)) == REFERENCE_TYPE))
2501     TREE_READONLY (decl) = 1;
2502   if (type_quals & TYPE_QUAL_VOLATILE)
2503     {
2504       TREE_SIDE_EFFECTS (decl) = 1;
2505       TREE_THIS_VOLATILE (decl) = 1;
2506     }
2507   if (type_quals & TYPE_QUAL_RESTRICT)
2508     {
2509       if (!TREE_TYPE (decl)
2510           || !POINTER_TYPE_P (TREE_TYPE (decl))
2511           || !C_TYPE_OBJECT_OR_INCOMPLETE_P (TREE_TYPE (TREE_TYPE (decl))))
2512         error ("invalid use of `restrict'");
2513       else if (flag_strict_aliasing)
2514         /* Indicate we need to make a unique alias set for this pointer.
2515            We can't do it here because it might be pointing to an
2516            incomplete type.  */
2517         DECL_POINTER_ALIAS_SET (decl) = -2;
2518     }
2519 }
2520
2521 /* Return the typed-based alias set for T, which may be an expression
2522    or a type.  Return -1 if we don't do anything special.  */
2523
2524 HOST_WIDE_INT
2525 c_common_get_alias_set (t)
2526      tree t;
2527 {
2528   tree u;
2529
2530   /* Permit type-punning when accessing a union, provided the access
2531      is directly through the union.  For example, this code does not
2532      permit taking the address of a union member and then storing
2533      through it.  Even the type-punning allowed here is a GCC
2534      extension, albeit a common and useful one; the C standard says
2535      that such accesses have implementation-defined behavior.  */
2536   for (u = t;
2537        TREE_CODE (u) == COMPONENT_REF || TREE_CODE (u) == ARRAY_REF;
2538        u = TREE_OPERAND (u, 0))
2539     if (TREE_CODE (u) == COMPONENT_REF
2540         && TREE_CODE (TREE_TYPE (TREE_OPERAND (u, 0))) == UNION_TYPE)
2541       return 0;
2542
2543   /* That's all the expressions we handle specially.  */
2544   if (! TYPE_P (t))
2545     return -1;
2546
2547   /* The C standard guarantess that any object may be accessed via an
2548      lvalue that has character type.  */
2549   if (t == char_type_node
2550       || t == signed_char_type_node
2551       || t == unsigned_char_type_node)
2552     return 0;
2553
2554   /* If it has the may_alias attribute, it can alias anything.  */
2555   if (lookup_attribute ("may_alias", TYPE_ATTRIBUTES (t)))
2556     return 0;
2557
2558   /* The C standard specifically allows aliasing between signed and
2559      unsigned variants of the same type.  We treat the signed
2560      variant as canonical.  */
2561   if (TREE_CODE (t) == INTEGER_TYPE && TREE_UNSIGNED (t))
2562     {
2563       tree t1 = c_common_signed_type (t);
2564
2565       /* t1 == t can happen for boolean nodes which are always unsigned.  */
2566       if (t1 != t)
2567         return get_alias_set (t1);
2568     }
2569   else if (POINTER_TYPE_P (t))
2570     {
2571       tree t1;
2572
2573       /* Unfortunately, there is no canonical form of a pointer type.
2574          In particular, if we have `typedef int I', then `int *', and
2575          `I *' are different types.  So, we have to pick a canonical
2576          representative.  We do this below.
2577
2578          Technically, this approach is actually more conservative that
2579          it needs to be.  In particular, `const int *' and `int *'
2580          should be in different alias sets, according to the C and C++
2581          standard, since their types are not the same, and so,
2582          technically, an `int **' and `const int **' cannot point at
2583          the same thing.
2584
2585          But, the standard is wrong.  In particular, this code is
2586          legal C++:
2587
2588             int *ip;
2589             int **ipp = &ip;
2590             const int* const* cipp = &ipp;
2591
2592          And, it doesn't make sense for that to be legal unless you
2593          can dereference IPP and CIPP.  So, we ignore cv-qualifiers on
2594          the pointed-to types.  This issue has been reported to the
2595          C++ committee.  */
2596       t1 = build_type_no_quals (t);
2597       if (t1 != t)
2598         return get_alias_set (t1);
2599     }
2600
2601   return -1;
2602 }
2603 \f
2604 /* Compute the value of 'sizeof (TYPE)' or '__alignof__ (TYPE)', where the
2605    second parameter indicates which OPERATOR is being applied.  The COMPLAIN
2606    flag controls whether we should diagnose possibly ill-formed
2607    constructs or not.  */
2608 tree
2609 c_sizeof_or_alignof_type (type, op, complain)
2610      tree type;
2611      enum tree_code op;
2612      int complain;
2613 {
2614   const char *op_name;
2615   tree value = NULL;
2616   enum tree_code type_code = TREE_CODE (type);
2617
2618   my_friendly_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR, 20020720);
2619   op_name = op == SIZEOF_EXPR ? "sizeof" : "__alignof__";
2620
2621   if (type_code == FUNCTION_TYPE)
2622     {
2623       if (op == SIZEOF_EXPR)
2624         {
2625           if (complain && (pedantic || warn_pointer_arith))
2626             pedwarn ("invalid application of `sizeof' to a function type");
2627           value = size_one_node;
2628         }
2629       else
2630         value = size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT);
2631     }
2632   else if (type_code == VOID_TYPE || type_code == ERROR_MARK)
2633     {
2634       if (type_code == VOID_TYPE
2635           && complain && (pedantic || warn_pointer_arith))
2636         pedwarn ("invalid application of `%s' to a void type", op_name);
2637       value = size_one_node;
2638     }
2639   else if (!COMPLETE_TYPE_P (type))
2640     {
2641       if (complain)
2642         error ("invalid application of `%s' to an incomplete type", op_name);
2643       value = size_zero_node;
2644     }
2645   else
2646     {
2647       if (op == SIZEOF_EXPR)
2648         /* Convert in case a char is more than one unit.  */
2649         value = size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
2650                             size_int (TYPE_PRECISION (char_type_node)
2651                                       / BITS_PER_UNIT));
2652       else
2653         value = size_int (TYPE_ALIGN (type) / BITS_PER_UNIT);
2654     }
2655
2656   /* VALUE will have an integer type with TYPE_IS_SIZETYPE set.
2657      TYPE_IS_SIZETYPE means that certain things (like overflow) will
2658      never happen.  However, this node should really have type
2659      `size_t', which is just a typedef for an ordinary integer type.  */
2660   value = fold (build1 (NOP_EXPR, c_size_type_node, value));
2661   my_friendly_assert (!TYPE_IS_SIZETYPE (TREE_TYPE (value)), 20001021);
2662
2663   return value;
2664 }
2665
2666 /* Implement the __alignof keyword: Return the minimum required
2667    alignment of EXPR, measured in bytes.  For VAR_DECL's and
2668    FIELD_DECL's return DECL_ALIGN (which can be set from an
2669    "aligned" __attribute__ specification).  */
2670
2671 tree
2672 c_alignof_expr (expr)
2673      tree expr;
2674 {
2675   tree t;
2676
2677   if (TREE_CODE (expr) == VAR_DECL)
2678     t = size_int (DECL_ALIGN (expr) / BITS_PER_UNIT);
2679
2680   else if (TREE_CODE (expr) == COMPONENT_REF
2681            && DECL_C_BIT_FIELD (TREE_OPERAND (expr, 1)))
2682     {
2683       error ("`__alignof' applied to a bit-field");
2684       t = size_one_node;
2685     }
2686   else if (TREE_CODE (expr) == COMPONENT_REF
2687            && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL)
2688     t = size_int (DECL_ALIGN (TREE_OPERAND (expr, 1)) / BITS_PER_UNIT);
2689
2690   else if (TREE_CODE (expr) == INDIRECT_REF)
2691     {
2692       tree t = TREE_OPERAND (expr, 0);
2693       tree best = t;
2694       int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
2695
2696       while (TREE_CODE (t) == NOP_EXPR
2697              && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE)
2698         {
2699           int thisalign;
2700
2701           t = TREE_OPERAND (t, 0);
2702           thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
2703           if (thisalign > bestalign)
2704             best = t, bestalign = thisalign;
2705         }
2706       return c_alignof (TREE_TYPE (TREE_TYPE (best)));
2707     }
2708   else
2709     return c_alignof (TREE_TYPE (expr));
2710
2711   return fold (build1 (NOP_EXPR, c_size_type_node, t));
2712 }
2713 \f
2714 /* Handle C and C++ default attributes.  */
2715
2716 enum built_in_attribute
2717 {
2718 #define DEF_ATTR_NULL_TREE(ENUM) ENUM,
2719 #define DEF_ATTR_INT(ENUM, VALUE) ENUM,
2720 #define DEF_ATTR_IDENT(ENUM, STRING) ENUM,
2721 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) ENUM,
2722 #define DEF_FN_ATTR(NAME, ATTRS, PREDICATE) /* No entry needed in enum.  */
2723 #include "builtin-attrs.def"
2724 #undef DEF_ATTR_NULL_TREE
2725 #undef DEF_ATTR_INT
2726 #undef DEF_ATTR_IDENT
2727 #undef DEF_ATTR_TREE_LIST
2728 #undef DEF_FN_ATTR
2729   ATTR_LAST
2730 };
2731
2732 static GTY(()) tree built_in_attributes[(int) ATTR_LAST];
2733
2734 static bool c_attrs_initialized = false;
2735
2736 static void c_init_attributes PARAMS ((void));
2737
2738 /* Build tree nodes and builtin functions common to both C and C++ language
2739    frontends.  */
2740
2741 void
2742 c_common_nodes_and_builtins ()
2743 {
2744   enum builtin_type
2745   {
2746 #define DEF_PRIMITIVE_TYPE(NAME, VALUE) NAME,
2747 #define DEF_FUNCTION_TYPE_0(NAME, RETURN) NAME,
2748 #define DEF_FUNCTION_TYPE_1(NAME, RETURN, ARG1) NAME,
2749 #define DEF_FUNCTION_TYPE_2(NAME, RETURN, ARG1, ARG2) NAME,
2750 #define DEF_FUNCTION_TYPE_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
2751 #define DEF_FUNCTION_TYPE_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
2752 #define DEF_FUNCTION_TYPE_VAR_0(NAME, RETURN) NAME,
2753 #define DEF_FUNCTION_TYPE_VAR_1(NAME, RETURN, ARG1) NAME,
2754 #define DEF_FUNCTION_TYPE_VAR_2(NAME, RETURN, ARG1, ARG2) NAME,
2755 #define DEF_POINTER_TYPE(NAME, TYPE) NAME,
2756 #include "builtin-types.def"
2757 #undef DEF_PRIMITIVE_TYPE
2758 #undef DEF_FUNCTION_TYPE_0
2759 #undef DEF_FUNCTION_TYPE_1
2760 #undef DEF_FUNCTION_TYPE_2
2761 #undef DEF_FUNCTION_TYPE_3
2762 #undef DEF_FUNCTION_TYPE_4
2763 #undef DEF_FUNCTION_TYPE_VAR_0
2764 #undef DEF_FUNCTION_TYPE_VAR_1
2765 #undef DEF_FUNCTION_TYPE_VAR_2
2766 #undef DEF_POINTER_TYPE
2767     BT_LAST
2768   };
2769
2770   typedef enum builtin_type builtin_type;
2771
2772   tree builtin_types[(int) BT_LAST];
2773   int wchar_type_size;
2774   tree array_domain_type;
2775   tree va_list_ref_type_node;
2776   tree va_list_arg_type_node;
2777
2778   /* Define `int' and `char' first so that dbx will output them first.  */
2779   record_builtin_type (RID_INT, NULL, integer_type_node);
2780   record_builtin_type (RID_CHAR, "char", char_type_node);
2781
2782   /* `signed' is the same as `int'.  FIXME: the declarations of "signed",
2783      "unsigned long", "long long unsigned" and "unsigned short" were in C++
2784      but not C.  Are the conditionals here needed?  */
2785   if (c_language == clk_cplusplus)
2786     record_builtin_type (RID_SIGNED, NULL, integer_type_node);
2787   record_builtin_type (RID_LONG, "long int", long_integer_type_node);
2788   record_builtin_type (RID_UNSIGNED, "unsigned int", unsigned_type_node);
2789   record_builtin_type (RID_MAX, "long unsigned int",
2790                        long_unsigned_type_node);
2791   if (c_language == clk_cplusplus)
2792     record_builtin_type (RID_MAX, "unsigned long", long_unsigned_type_node);
2793   record_builtin_type (RID_MAX, "long long int",
2794                        long_long_integer_type_node);
2795   record_builtin_type (RID_MAX, "long long unsigned int",
2796                        long_long_unsigned_type_node);
2797   if (c_language == clk_cplusplus)
2798     record_builtin_type (RID_MAX, "long long unsigned",
2799                          long_long_unsigned_type_node);
2800   record_builtin_type (RID_SHORT, "short int", short_integer_type_node);
2801   record_builtin_type (RID_MAX, "short unsigned int",
2802                        short_unsigned_type_node);
2803   if (c_language == clk_cplusplus)
2804     record_builtin_type (RID_MAX, "unsigned short",
2805                          short_unsigned_type_node);
2806
2807   /* Define both `signed char' and `unsigned char'.  */
2808   record_builtin_type (RID_MAX, "signed char", signed_char_type_node);
2809   record_builtin_type (RID_MAX, "unsigned char", unsigned_char_type_node);
2810
2811   /* These are types that c_common_type_for_size and
2812      c_common_type_for_mode use.  */
2813   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2814                                             intQI_type_node));
2815   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2816                                             intHI_type_node));
2817   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2818                                             intSI_type_node));
2819   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2820                                             intDI_type_node));
2821 #if HOST_BITS_PER_WIDE_INT >= 64
2822   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2823                                             get_identifier ("__int128_t"),
2824                                             intTI_type_node));
2825 #endif
2826   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2827                                             unsigned_intQI_type_node));
2828   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2829                                             unsigned_intHI_type_node));
2830   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2831                                             unsigned_intSI_type_node));
2832   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2833                                             unsigned_intDI_type_node));
2834 #if HOST_BITS_PER_WIDE_INT >= 64
2835   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2836                                             get_identifier ("__uint128_t"),
2837                                             unsigned_intTI_type_node));
2838 #endif
2839
2840   /* Create the widest literal types.  */
2841   widest_integer_literal_type_node
2842     = make_signed_type (HOST_BITS_PER_WIDE_INT * 2);
2843   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2844                                             widest_integer_literal_type_node));
2845
2846   widest_unsigned_literal_type_node
2847     = make_unsigned_type (HOST_BITS_PER_WIDE_INT * 2);
2848   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2849                                             widest_unsigned_literal_type_node));
2850
2851   /* `unsigned long' is the standard type for sizeof.
2852      Note that stddef.h uses `unsigned long',
2853      and this must agree, even if long and int are the same size.  */
2854   c_size_type_node =
2855     TREE_TYPE (identifier_global_value (get_identifier (SIZE_TYPE)));
2856   signed_size_type_node = c_common_signed_type (c_size_type_node);
2857   set_sizetype (c_size_type_node);
2858
2859   build_common_tree_nodes_2 (flag_short_double);
2860
2861   record_builtin_type (RID_FLOAT, NULL, float_type_node);
2862   record_builtin_type (RID_DOUBLE, NULL, double_type_node);
2863   record_builtin_type (RID_MAX, "long double", long_double_type_node);
2864
2865   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2866                                             get_identifier ("complex int"),
2867                                             complex_integer_type_node));
2868   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2869                                             get_identifier ("complex float"),
2870                                             complex_float_type_node));
2871   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2872                                             get_identifier ("complex double"),
2873                                             complex_double_type_node));
2874   (*lang_hooks.decls.pushdecl)
2875     (build_decl (TYPE_DECL, get_identifier ("complex long double"),
2876                  complex_long_double_type_node));
2877
2878   /* Types which are common to the fortran compiler and libf2c.  When
2879      changing these, you also need to be concerned with f/com.h.  */
2880
2881   if (TYPE_PRECISION (float_type_node)
2882       == TYPE_PRECISION (long_integer_type_node))
2883     {
2884       g77_integer_type_node = long_integer_type_node;
2885       g77_uinteger_type_node = long_unsigned_type_node;
2886     }
2887   else if (TYPE_PRECISION (float_type_node)
2888            == TYPE_PRECISION (integer_type_node))
2889     {
2890       g77_integer_type_node = integer_type_node;
2891       g77_uinteger_type_node = unsigned_type_node;
2892     }
2893   else
2894     g77_integer_type_node = g77_uinteger_type_node = NULL_TREE;
2895
2896   if (g77_integer_type_node != NULL_TREE)
2897     {
2898       (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2899                                                 get_identifier ("__g77_integer"),
2900                                                 g77_integer_type_node));
2901       (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2902                                                 get_identifier ("__g77_uinteger"),
2903                                                 g77_uinteger_type_node));
2904     }
2905
2906   if (TYPE_PRECISION (float_type_node) * 2
2907       == TYPE_PRECISION (long_integer_type_node))
2908     {
2909       g77_longint_type_node = long_integer_type_node;
2910       g77_ulongint_type_node = long_unsigned_type_node;
2911     }
2912   else if (TYPE_PRECISION (float_type_node) * 2
2913            == TYPE_PRECISION (long_long_integer_type_node))
2914     {
2915       g77_longint_type_node = long_long_integer_type_node;
2916       g77_ulongint_type_node = long_long_unsigned_type_node;
2917     }
2918   else
2919     g77_longint_type_node = g77_ulongint_type_node = NULL_TREE;
2920
2921   if (g77_longint_type_node != NULL_TREE)
2922     {
2923       (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2924                                                 get_identifier ("__g77_longint"),
2925                                                 g77_longint_type_node));
2926       (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2927                                                 get_identifier ("__g77_ulongint"),
2928                                                 g77_ulongint_type_node));
2929     }
2930
2931   record_builtin_type (RID_VOID, NULL, void_type_node);
2932
2933   void_zero_node = build_int_2 (0, 0);
2934   TREE_TYPE (void_zero_node) = void_type_node;
2935
2936   void_list_node = build_void_list_node ();
2937
2938   /* Make a type to be the domain of a few array types
2939      whose domains don't really matter.
2940      200 is small enough that it always fits in size_t
2941      and large enough that it can hold most function names for the
2942      initializations of __FUNCTION__ and __PRETTY_FUNCTION__.  */
2943   array_domain_type = build_index_type (size_int (200));
2944
2945   /* Make a type for arrays of characters.
2946      With luck nothing will ever really depend on the length of this
2947      array type.  */
2948   char_array_type_node
2949     = build_array_type (char_type_node, array_domain_type);
2950
2951   /* Likewise for arrays of ints.  */
2952   int_array_type_node
2953     = build_array_type (integer_type_node, array_domain_type);
2954
2955   string_type_node = build_pointer_type (char_type_node);
2956   const_string_type_node
2957     = build_pointer_type (build_qualified_type
2958                           (char_type_node, TYPE_QUAL_CONST));
2959
2960   (*targetm.init_builtins) ();
2961
2962   /* This is special for C++ so functions can be overloaded.  */
2963   wchar_type_node = get_identifier (MODIFIED_WCHAR_TYPE);
2964   wchar_type_node = TREE_TYPE (identifier_global_value (wchar_type_node));
2965   wchar_type_size = TYPE_PRECISION (wchar_type_node);
2966   if (c_language == clk_cplusplus)
2967     {
2968       if (TREE_UNSIGNED (wchar_type_node))
2969         wchar_type_node = make_unsigned_type (wchar_type_size);
2970       else
2971         wchar_type_node = make_signed_type (wchar_type_size);
2972       record_builtin_type (RID_WCHAR, "wchar_t", wchar_type_node);
2973     }
2974   else
2975     {
2976       signed_wchar_type_node = c_common_signed_type (wchar_type_node);
2977       unsigned_wchar_type_node = c_common_unsigned_type (wchar_type_node);
2978     }
2979
2980   /* This is for wide string constants.  */
2981   wchar_array_type_node
2982     = build_array_type (wchar_type_node, array_domain_type);
2983
2984   wint_type_node =
2985     TREE_TYPE (identifier_global_value (get_identifier (WINT_TYPE)));
2986
2987   intmax_type_node =
2988     TREE_TYPE (identifier_global_value (get_identifier (INTMAX_TYPE)));
2989   uintmax_type_node =
2990     TREE_TYPE (identifier_global_value (get_identifier (UINTMAX_TYPE)));
2991
2992   default_function_type = build_function_type (integer_type_node, NULL_TREE);
2993   ptrdiff_type_node
2994     = TREE_TYPE (identifier_global_value (get_identifier (PTRDIFF_TYPE)));
2995   unsigned_ptrdiff_type_node = c_common_unsigned_type (ptrdiff_type_node);
2996
2997   (*lang_hooks.decls.pushdecl)
2998     (build_decl (TYPE_DECL, get_identifier ("__builtin_va_list"),
2999                  va_list_type_node));
3000
3001   (*lang_hooks.decls.pushdecl)
3002     (build_decl (TYPE_DECL, get_identifier ("__builtin_ptrdiff_t"),
3003                  ptrdiff_type_node));
3004
3005   (*lang_hooks.decls.pushdecl)
3006     (build_decl (TYPE_DECL, get_identifier ("__builtin_size_t"),
3007                  sizetype));
3008
3009   if (TREE_CODE (va_list_type_node) == ARRAY_TYPE)
3010     {
3011       va_list_arg_type_node = va_list_ref_type_node =
3012         build_pointer_type (TREE_TYPE (va_list_type_node));
3013     }
3014   else
3015     {
3016       va_list_arg_type_node = va_list_type_node;
3017       va_list_ref_type_node = build_reference_type (va_list_type_node);
3018     }
3019
3020 #define DEF_PRIMITIVE_TYPE(ENUM, VALUE) \
3021   builtin_types[(int) ENUM] = VALUE;
3022 #define DEF_FUNCTION_TYPE_0(ENUM, RETURN)               \
3023   builtin_types[(int) ENUM]                             \
3024     = build_function_type (builtin_types[(int) RETURN], \
3025                            void_list_node);
3026 #define DEF_FUNCTION_TYPE_1(ENUM, RETURN, ARG1)                         \
3027   builtin_types[(int) ENUM]                                             \
3028     = build_function_type (builtin_types[(int) RETURN],                 \
3029                            tree_cons (NULL_TREE,                        \
3030                                       builtin_types[(int) ARG1],        \
3031                                       void_list_node));
3032 #define DEF_FUNCTION_TYPE_2(ENUM, RETURN, ARG1, ARG2)   \
3033   builtin_types[(int) ENUM]                             \
3034     = build_function_type                               \
3035       (builtin_types[(int) RETURN],                     \
3036        tree_cons (NULL_TREE,                            \
3037                   builtin_types[(int) ARG1],            \
3038                   tree_cons (NULL_TREE,                 \
3039                              builtin_types[(int) ARG2], \
3040                              void_list_node)));
3041 #define DEF_FUNCTION_TYPE_3(ENUM, RETURN, ARG1, ARG2, ARG3)              \
3042   builtin_types[(int) ENUM]                                              \
3043     = build_function_type                                                \
3044       (builtin_types[(int) RETURN],                                      \
3045        tree_cons (NULL_TREE,                                             \
3046                   builtin_types[(int) ARG1],                             \
3047                   tree_cons (NULL_TREE,                                  \
3048                              builtin_types[(int) ARG2],                  \
3049                              tree_cons (NULL_TREE,                       \
3050                                         builtin_types[(int) ARG3],       \
3051                                         void_list_node))));
3052 #define DEF_FUNCTION_TYPE_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4)       \
3053   builtin_types[(int) ENUM]                                             \
3054     = build_function_type                                               \
3055       (builtin_types[(int) RETURN],                                     \
3056        tree_cons (NULL_TREE,                                            \
3057                   builtin_types[(int) ARG1],                            \
3058                   tree_cons (NULL_TREE,                                 \
3059                              builtin_types[(int) ARG2],                 \
3060                              tree_cons                                  \
3061                              (NULL_TREE,                                \
3062                               builtin_types[(int) ARG3],                \
3063                               tree_cons (NULL_TREE,                     \
3064                                          builtin_types[(int) ARG4],     \
3065                                          void_list_node)))));
3066 #define DEF_FUNCTION_TYPE_VAR_0(ENUM, RETURN)                           \
3067   builtin_types[(int) ENUM]                                             \
3068     = build_function_type (builtin_types[(int) RETURN], NULL_TREE);
3069 #define DEF_FUNCTION_TYPE_VAR_1(ENUM, RETURN, ARG1)                      \
3070    builtin_types[(int) ENUM]                                             \
3071     = build_function_type (builtin_types[(int) RETURN],                  \
3072                            tree_cons (NULL_TREE,                         \
3073                                       builtin_types[(int) ARG1],         \
3074                                       NULL_TREE));
3075
3076 #define DEF_FUNCTION_TYPE_VAR_2(ENUM, RETURN, ARG1, ARG2)       \
3077    builtin_types[(int) ENUM]                                    \
3078     = build_function_type                                       \
3079       (builtin_types[(int) RETURN],                             \
3080        tree_cons (NULL_TREE,                                    \
3081                   builtin_types[(int) ARG1],                    \
3082                   tree_cons (NULL_TREE,                         \
3083                              builtin_types[(int) ARG2],         \
3084                              NULL_TREE)));
3085 #define DEF_POINTER_TYPE(ENUM, TYPE)                    \
3086   builtin_types[(int) ENUM]                             \
3087     = build_pointer_type (builtin_types[(int) TYPE]);
3088 #include "builtin-types.def"
3089 #undef DEF_PRIMITIVE_TYPE
3090 #undef DEF_FUNCTION_TYPE_1
3091 #undef DEF_FUNCTION_TYPE_2
3092 #undef DEF_FUNCTION_TYPE_3
3093 #undef DEF_FUNCTION_TYPE_4
3094 #undef DEF_FUNCTION_TYPE_VAR_0
3095 #undef DEF_FUNCTION_TYPE_VAR_1
3096 #undef DEF_POINTER_TYPE
3097
3098   if (!c_attrs_initialized)
3099     c_init_attributes ();
3100
3101 #define DEF_BUILTIN(ENUM, NAME, CLASS, TYPE, LIBTYPE,                   \
3102                     BOTH_P, FALLBACK_P, NONANSI_P, ATTRS)               \
3103   if (NAME)                                                             \
3104     {                                                                   \
3105       tree decl;                                                        \
3106                                                                         \
3107       if (strncmp (NAME, "__builtin_", strlen ("__builtin_")) != 0)     \
3108         abort ();                                                       \
3109                                                                         \
3110       if (!BOTH_P)                                                      \
3111         decl = builtin_function (NAME, builtin_types[TYPE], ENUM,       \
3112                                  CLASS,                                 \
3113                                  (FALLBACK_P                            \
3114                                   ? (NAME + strlen ("__builtin_"))      \
3115                                   : NULL),                              \
3116                                  built_in_attributes[(int) ATTRS]);     \
3117       else                                                              \
3118         decl = builtin_function_2 (NAME,                                \
3119                                    NAME + strlen ("__builtin_"),        \
3120                                    builtin_types[TYPE],                 \
3121                                    builtin_types[LIBTYPE],              \
3122                                    ENUM,                                \
3123                                    CLASS,                               \
3124                                    FALLBACK_P,                          \
3125                                    NONANSI_P,                           \
3126                                    built_in_attributes[(int) ATTRS]);   \
3127                                                                         \
3128       built_in_decls[(int) ENUM] = decl;                                \
3129     }
3130 #include "builtins.def"
3131 #undef DEF_BUILTIN
3132
3133   main_identifier_node = get_identifier ("main");
3134 }
3135
3136 tree
3137 build_va_arg (expr, type)
3138      tree expr, type;
3139 {
3140   return build1 (VA_ARG_EXPR, type, expr);
3141 }
3142
3143
3144 /* Linked list of disabled built-in functions.  */
3145
3146 typedef struct disabled_builtin
3147 {
3148   const char *name;
3149   struct disabled_builtin *next;
3150 } disabled_builtin;
3151 static disabled_builtin *disabled_builtins = NULL;
3152
3153 static bool builtin_function_disabled_p PARAMS ((const char *));
3154
3155 /* Disable a built-in function specified by -fno-builtin-NAME.  If NAME
3156    begins with "__builtin_", give an error.  */
3157
3158 void
3159 disable_builtin_function (name)
3160      const char *name;
3161 {
3162   if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
3163     error ("cannot disable built-in function `%s'", name);
3164   else
3165     {
3166       disabled_builtin *new = xmalloc (sizeof (disabled_builtin));
3167       new->name = name;
3168       new->next = disabled_builtins;
3169       disabled_builtins = new;
3170     }
3171 }
3172
3173
3174 /* Return true if the built-in function NAME has been disabled, false
3175    otherwise.  */
3176
3177 static bool
3178 builtin_function_disabled_p (name)
3179      const char *name;
3180 {
3181   disabled_builtin *p;
3182   for (p = disabled_builtins; p != NULL; p = p->next)
3183     {
3184       if (strcmp (name, p->name) == 0)
3185         return true;
3186     }
3187   return false;
3188 }
3189
3190
3191 /* Possibly define a builtin function with one or two names.  BUILTIN_NAME
3192    is an __builtin_-prefixed name; NAME is the ordinary name; one or both
3193    of these may be NULL (though both being NULL is useless).
3194    BUILTIN_TYPE is the type of the __builtin_-prefixed function;
3195    TYPE is the type of the function with the ordinary name.  These
3196    may differ if the ordinary name is declared with a looser type to avoid
3197    conflicts with headers.  FUNCTION_CODE and CLASS are as for
3198    builtin_function.  If LIBRARY_NAME_P is nonzero, NAME is passed as
3199    the LIBRARY_NAME parameter to builtin_function when declaring BUILTIN_NAME.
3200    If NONANSI_P is nonzero, the name NAME is treated as a non-ANSI name;
3201    ATTRS is the tree list representing the builtin's function attributes.
3202    Returns the declaration of BUILTIN_NAME, if any, otherwise
3203    the declaration of NAME.  Does not declare NAME if flag_no_builtin,
3204    or if NONANSI_P and flag_no_nonansi_builtin.  */
3205
3206 static tree
3207 builtin_function_2 (builtin_name, name, builtin_type, type, function_code,
3208                     class, library_name_p, nonansi_p, attrs)
3209      const char *builtin_name;
3210      const char *name;
3211      tree builtin_type;
3212      tree type;
3213      int function_code;
3214      enum built_in_class class;
3215      int library_name_p;
3216      int nonansi_p;
3217      tree attrs;
3218 {
3219   tree bdecl = NULL_TREE;
3220   tree decl = NULL_TREE;
3221   if (builtin_name != 0)
3222     {
3223       bdecl = builtin_function (builtin_name, builtin_type, function_code,
3224                                 class, library_name_p ? name : NULL,
3225                                 attrs);
3226     }
3227   if (name != 0 && !flag_no_builtin && !builtin_function_disabled_p (name)
3228       && !(nonansi_p && flag_no_nonansi_builtin))
3229     {
3230       decl = builtin_function (name, type, function_code, class, NULL,
3231                                attrs);
3232       if (nonansi_p)
3233         DECL_BUILT_IN_NONANSI (decl) = 1;
3234     }
3235   return (bdecl != 0 ? bdecl : decl);
3236 }
3237 \f
3238 /* Nonzero if the type T promotes to int.  This is (nearly) the
3239    integral promotions defined in ISO C99 6.3.1.1/2.  */
3240
3241 bool
3242 c_promoting_integer_type_p (t)
3243      tree t;
3244 {
3245   switch (TREE_CODE (t))
3246     {
3247     case INTEGER_TYPE:
3248       return (TYPE_MAIN_VARIANT (t) == char_type_node
3249               || TYPE_MAIN_VARIANT (t) == signed_char_type_node
3250               || TYPE_MAIN_VARIANT (t) == unsigned_char_type_node
3251               || TYPE_MAIN_VARIANT (t) == short_integer_type_node
3252               || TYPE_MAIN_VARIANT (t) == short_unsigned_type_node
3253               || TYPE_PRECISION (t) < TYPE_PRECISION (integer_type_node));
3254
3255     case ENUMERAL_TYPE:
3256       /* ??? Technically all enumerations not larger than an int
3257          promote to an int.  But this is used along code paths
3258          that only want to notice a size change.  */
3259       return TYPE_PRECISION (t) < TYPE_PRECISION (integer_type_node);
3260
3261     case BOOLEAN_TYPE:
3262       return 1;
3263
3264     default:
3265       return 0;
3266     }
3267 }
3268
3269 /* Return 1 if PARMS specifies a fixed number of parameters
3270    and none of their types is affected by default promotions.  */
3271
3272 int
3273 self_promoting_args_p (parms)
3274      tree parms;
3275 {
3276   tree t;
3277   for (t = parms; t; t = TREE_CHAIN (t))
3278     {
3279       tree type = TREE_VALUE (t);
3280
3281       if (TREE_CHAIN (t) == 0 && type != void_type_node)
3282         return 0;
3283
3284       if (type == 0)
3285         return 0;
3286
3287       if (TYPE_MAIN_VARIANT (type) == float_type_node)
3288         return 0;
3289
3290       if (c_promoting_integer_type_p (type))
3291         return 0;
3292     }
3293   return 1;
3294 }
3295
3296 /* Recursively examines the array elements of TYPE, until a non-array
3297    element type is found.  */
3298
3299 tree
3300 strip_array_types (type)
3301      tree type;
3302 {
3303   while (TREE_CODE (type) == ARRAY_TYPE)
3304     type = TREE_TYPE (type);
3305
3306   return type;
3307 }
3308
3309 static tree expand_unordered_cmp PARAMS ((tree, tree, enum tree_code,
3310                                           enum tree_code));
3311
3312 /* Expand a call to an unordered comparison function such as
3313    __builtin_isgreater().  FUNCTION is the function's declaration and
3314    PARAMS a list of the values passed.  For __builtin_isunordered(),
3315    UNORDERED_CODE is UNORDERED_EXPR and ORDERED_CODE is NOP_EXPR.  In
3316    other cases, UNORDERED_CODE and ORDERED_CODE are comparison codes
3317    that give the opposite of the desired result.  UNORDERED_CODE is
3318    used for modes that can hold NaNs and ORDERED_CODE is used for the
3319    rest.  */
3320
3321 static tree
3322 expand_unordered_cmp (function, params, unordered_code, ordered_code)
3323      tree function, params;
3324      enum tree_code unordered_code, ordered_code;
3325 {
3326   tree arg0, arg1, type;
3327   enum tree_code code0, code1;
3328
3329   /* Check that we have exactly two arguments.  */
3330   if (params == 0 || TREE_CHAIN (params) == 0)
3331     {
3332       error ("too few arguments to function `%s'",
3333              IDENTIFIER_POINTER (DECL_NAME (function)));
3334       return error_mark_node;
3335     }
3336   else if (TREE_CHAIN (TREE_CHAIN (params)) != 0)
3337     {
3338       error ("too many arguments to function `%s'",
3339              IDENTIFIER_POINTER (DECL_NAME (function)));
3340       return error_mark_node;
3341     }
3342
3343   arg0 = TREE_VALUE (params);
3344   arg1 = TREE_VALUE (TREE_CHAIN (params));
3345
3346   code0 = TREE_CODE (TREE_TYPE (arg0));
3347   code1 = TREE_CODE (TREE_TYPE (arg1));
3348
3349   /* Make sure that the arguments have a common type of REAL.  */
3350   type = 0;
3351   if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3352       && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3353     type = common_type (TREE_TYPE (arg0), TREE_TYPE (arg1));
3354
3355   if (type == 0 || TREE_CODE (type) != REAL_TYPE)
3356     {
3357       error ("non-floating-point argument to function `%s'",
3358              IDENTIFIER_POINTER (DECL_NAME (function)));
3359       return error_mark_node;
3360     }
3361
3362   if (unordered_code == UNORDERED_EXPR)
3363     {
3364       if (MODE_HAS_NANS (TYPE_MODE (type)))
3365         return build_binary_op (unordered_code,
3366                                 convert (type, arg0),
3367                                 convert (type, arg1),
3368                                 0);
3369       else
3370         return integer_zero_node;
3371     }
3372
3373   return build_unary_op (TRUTH_NOT_EXPR,
3374                          build_binary_op (MODE_HAS_NANS (TYPE_MODE (type))
3375                                           ? unordered_code
3376                                           : ordered_code,
3377                                           convert (type, arg0),
3378                                           convert (type, arg1),
3379                                           0),
3380                          0);
3381 }
3382
3383
3384 /* Recognize certain built-in functions so we can make tree-codes
3385    other than CALL_EXPR.  We do this when it enables fold-const.c
3386    to do something useful.  */
3387 /* ??? By rights this should go in builtins.c, but only C and C++
3388    implement build_{binary,unary}_op.  Not exactly sure what bits
3389    of functionality are actually needed from those functions, or
3390    where the similar functionality exists in the other front ends.  */
3391
3392 tree
3393 expand_tree_builtin (function, params, coerced_params)
3394      tree function, params, coerced_params;
3395 {
3396   if (DECL_BUILT_IN_CLASS (function) != BUILT_IN_NORMAL)
3397     return NULL_TREE;
3398
3399   switch (DECL_FUNCTION_CODE (function))
3400     {
3401     case BUILT_IN_ABS:
3402     case BUILT_IN_LABS:
3403     case BUILT_IN_LLABS:
3404     case BUILT_IN_IMAXABS:
3405     case BUILT_IN_FABS:
3406     case BUILT_IN_FABSL:
3407     case BUILT_IN_FABSF:
3408       if (coerced_params == 0)
3409         return integer_zero_node;
3410       return build_unary_op (ABS_EXPR, TREE_VALUE (coerced_params), 0);
3411
3412     case BUILT_IN_CONJ:
3413     case BUILT_IN_CONJF:
3414     case BUILT_IN_CONJL:
3415       if (coerced_params == 0)
3416         return integer_zero_node;
3417       return build_unary_op (CONJ_EXPR, TREE_VALUE (coerced_params), 0);
3418
3419     case BUILT_IN_CREAL:
3420     case BUILT_IN_CREALF:
3421     case BUILT_IN_CREALL:
3422       if (coerced_params == 0)
3423         return integer_zero_node;
3424       return build_unary_op (REALPART_EXPR, TREE_VALUE (coerced_params), 0);
3425
3426     case BUILT_IN_CIMAG:
3427     case BUILT_IN_CIMAGF:
3428     case BUILT_IN_CIMAGL:
3429       if (coerced_params == 0)
3430         return integer_zero_node;
3431       return build_unary_op (IMAGPART_EXPR, TREE_VALUE (coerced_params), 0);
3432
3433     case BUILT_IN_ISGREATER:
3434       return expand_unordered_cmp (function, params, UNLE_EXPR, LE_EXPR);
3435
3436     case BUILT_IN_ISGREATEREQUAL:
3437       return expand_unordered_cmp (function, params, UNLT_EXPR, LT_EXPR);
3438
3439     case BUILT_IN_ISLESS:
3440       return expand_unordered_cmp (function, params, UNGE_EXPR, GE_EXPR);
3441
3442     case BUILT_IN_ISLESSEQUAL:
3443       return expand_unordered_cmp (function, params, UNGT_EXPR, GT_EXPR);
3444
3445     case BUILT_IN_ISLESSGREATER:
3446       return expand_unordered_cmp (function, params, UNEQ_EXPR, EQ_EXPR);
3447
3448     case BUILT_IN_ISUNORDERED:
3449       return expand_unordered_cmp (function, params, UNORDERED_EXPR, NOP_EXPR);
3450
3451     default:
3452       break;
3453     }
3454
3455   return NULL_TREE;
3456 }
3457
3458 /* Returns non-zero if CODE is the code for a statement.  */
3459
3460 int
3461 statement_code_p (code)
3462      enum tree_code code;
3463 {
3464   switch (code)
3465     {
3466     case CLEANUP_STMT:
3467     case EXPR_STMT:
3468     case COMPOUND_STMT:
3469     case DECL_STMT:
3470     case IF_STMT:
3471     case FOR_STMT:
3472     case WHILE_STMT:
3473     case DO_STMT:
3474     case RETURN_STMT:
3475     case BREAK_STMT:
3476     case CONTINUE_STMT:
3477     case SCOPE_STMT:
3478     case SWITCH_STMT:
3479     case GOTO_STMT:
3480     case LABEL_STMT:
3481     case ASM_STMT:
3482     case FILE_STMT:
3483     case CASE_LABEL:
3484       return 1;
3485
3486     default:
3487       if (lang_statement_code_p)
3488         return (*lang_statement_code_p) (code);
3489       return 0;
3490     }
3491 }
3492
3493 /* Walk the statement tree, rooted at *tp.  Apply FUNC to all the
3494    sub-trees of *TP in a pre-order traversal.  FUNC is called with the
3495    DATA and the address of each sub-tree.  If FUNC returns a non-NULL
3496    value, the traversal is aborted, and the value returned by FUNC is
3497    returned.  If FUNC sets WALK_SUBTREES to zero, then the subtrees of
3498    the node being visited are not walked.
3499
3500    We don't need a without_duplicates variant of this one because the
3501    statement tree is a tree, not a graph.  */
3502
3503 tree
3504 walk_stmt_tree (tp, func, data)
3505      tree *tp;
3506      walk_tree_fn func;
3507      void *data;
3508 {
3509   enum tree_code code;
3510   int walk_subtrees;
3511   tree result;
3512   int i, len;
3513
3514 #define WALK_SUBTREE(NODE)                              \
3515   do                                                    \
3516     {                                                   \
3517       result = walk_stmt_tree (&(NODE), func, data);    \
3518       if (result)                                       \
3519         return result;                                  \
3520     }                                                   \
3521   while (0)
3522
3523   /* Skip empty subtrees.  */
3524   if (!*tp)
3525     return NULL_TREE;
3526
3527   /* Skip subtrees below non-statement nodes.  */
3528   if (!statement_code_p (TREE_CODE (*tp)))
3529     return NULL_TREE;
3530
3531   /* Call the function.  */
3532   walk_subtrees = 1;
3533   result = (*func) (tp, &walk_subtrees, data);
3534
3535   /* If we found something, return it.  */
3536   if (result)
3537     return result;
3538
3539   /* FUNC may have modified the tree, recheck that we're looking at a
3540      statement node.  */
3541   code = TREE_CODE (*tp);
3542   if (!statement_code_p (code))
3543     return NULL_TREE;
3544
3545   /* Visit the subtrees unless FUNC decided that there was nothing
3546      interesting below this point in the tree.  */
3547   if (walk_subtrees)
3548     {
3549       /* Walk over all the sub-trees of this operand.  Statement nodes
3550          never contain RTL, and we needn't worry about TARGET_EXPRs.  */
3551       len = TREE_CODE_LENGTH (code);
3552
3553       /* Go through the subtrees.  We need to do this in forward order so
3554          that the scope of a FOR_EXPR is handled properly.  */
3555       for (i = 0; i < len; ++i)
3556         WALK_SUBTREE (TREE_OPERAND (*tp, i));
3557     }
3558
3559   /* Finally visit the chain.  This can be tail-recursion optimized if
3560      we write it this way.  */
3561   return walk_stmt_tree (&TREE_CHAIN (*tp), func, data);
3562
3563 #undef WALK_SUBTREE
3564 }
3565
3566 /* Used to compare case labels.  K1 and K2 are actually tree nodes
3567    representing case labels, or NULL_TREE for a `default' label.
3568    Returns -1 if K1 is ordered before K2, -1 if K1 is ordered after
3569    K2, and 0 if K1 and K2 are equal.  */
3570
3571 int
3572 case_compare (k1, k2)
3573      splay_tree_key k1;
3574      splay_tree_key k2;
3575 {
3576   /* Consider a NULL key (such as arises with a `default' label) to be
3577      smaller than anything else.  */
3578   if (!k1)
3579     return k2 ? -1 : 0;
3580   else if (!k2)
3581     return k1 ? 1 : 0;
3582
3583   return tree_int_cst_compare ((tree) k1, (tree) k2);
3584 }
3585
3586 /* Process a case label for the range LOW_VALUE ... HIGH_VALUE.  If
3587    LOW_VALUE and HIGH_VALUE are both NULL_TREE then this case label is
3588    actually a `default' label.  If only HIGH_VALUE is NULL_TREE, then
3589    case label was declared using the usual C/C++ syntax, rather than
3590    the GNU case range extension.  CASES is a tree containing all the
3591    case ranges processed so far; COND is the condition for the
3592    switch-statement itself.  Returns the CASE_LABEL created, or
3593    ERROR_MARK_NODE if no CASE_LABEL is created.  */
3594
3595 tree
3596 c_add_case_label (cases, cond, low_value, high_value)
3597      splay_tree cases;
3598      tree cond;
3599      tree low_value;
3600      tree high_value;
3601 {
3602   tree type;
3603   tree label;
3604   tree case_label;
3605   splay_tree_node node;
3606
3607   /* Create the LABEL_DECL itself.  */
3608   label = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE);
3609   DECL_CONTEXT (label) = current_function_decl;
3610
3611   /* If there was an error processing the switch condition, bail now
3612      before we get more confused.  */
3613   if (!cond || cond == error_mark_node)
3614     {
3615       /* Add a label anyhow so that the back-end doesn't think that
3616          the beginning of the switch is unreachable.  */
3617       if (!cases->root)
3618         add_stmt (build_case_label (NULL_TREE, NULL_TREE, label));
3619       return error_mark_node;
3620     }
3621
3622   if ((low_value && TREE_TYPE (low_value)
3623        && POINTER_TYPE_P (TREE_TYPE (low_value)))
3624       || (high_value && TREE_TYPE (high_value)
3625           && POINTER_TYPE_P (TREE_TYPE (high_value))))
3626     error ("pointers are not permitted as case values");
3627
3628   /* Case ranges are a GNU extension.  */
3629   if (high_value && pedantic)
3630     {
3631       if (c_language == clk_cplusplus)
3632         pedwarn ("ISO C++ forbids range expressions in switch statements");
3633       else
3634         pedwarn ("ISO C forbids range expressions in switch statements");
3635     }
3636
3637   type = TREE_TYPE (cond);
3638   if (low_value)
3639     {
3640       low_value = check_case_value (low_value);
3641       low_value = convert_and_check (type, low_value);
3642     }
3643   if (high_value)
3644     {
3645       high_value = check_case_value (high_value);
3646       high_value = convert_and_check (type, high_value);
3647     }
3648
3649   /* If an error has occurred, bail out now.  */
3650   if (low_value == error_mark_node || high_value == error_mark_node)
3651     {
3652       if (!cases->root)
3653         add_stmt (build_case_label (NULL_TREE, NULL_TREE, label));
3654       return error_mark_node;
3655     }
3656
3657   /* If the LOW_VALUE and HIGH_VALUE are the same, then this isn't
3658      really a case range, even though it was written that way.  Remove
3659      the HIGH_VALUE to simplify later processing.  */
3660   if (tree_int_cst_equal (low_value, high_value))
3661     high_value = NULL_TREE;
3662   if (low_value && high_value
3663       && !tree_int_cst_lt (low_value, high_value))
3664     warning ("empty range specified");
3665
3666   /* Look up the LOW_VALUE in the table of case labels we already
3667      have.  */
3668   node = splay_tree_lookup (cases, (splay_tree_key) low_value);
3669   /* If there was not an exact match, check for overlapping ranges.
3670      There's no need to do this if there's no LOW_VALUE or HIGH_VALUE;
3671      that's a `default' label and the only overlap is an exact match.  */
3672   if (!node && (low_value || high_value))
3673     {
3674       splay_tree_node low_bound;
3675       splay_tree_node high_bound;
3676
3677       /* Even though there wasn't an exact match, there might be an
3678          overlap between this case range and another case range.
3679          Since we've (inductively) not allowed any overlapping case
3680          ranges, we simply need to find the greatest low case label
3681          that is smaller that LOW_VALUE, and the smallest low case
3682          label that is greater than LOW_VALUE.  If there is an overlap
3683          it will occur in one of these two ranges.  */
3684       low_bound = splay_tree_predecessor (cases,
3685                                           (splay_tree_key) low_value);
3686       high_bound = splay_tree_successor (cases,
3687                                          (splay_tree_key) low_value);
3688
3689       /* Check to see if the LOW_BOUND overlaps.  It is smaller than
3690          the LOW_VALUE, so there is no need to check unless the
3691          LOW_BOUND is in fact itself a case range.  */
3692       if (low_bound
3693           && CASE_HIGH ((tree) low_bound->value)
3694           && tree_int_cst_compare (CASE_HIGH ((tree) low_bound->value),
3695                                     low_value) >= 0)
3696         node = low_bound;
3697       /* Check to see if the HIGH_BOUND overlaps.  The low end of that
3698          range is bigger than the low end of the current range, so we
3699          are only interested if the current range is a real range, and
3700          not an ordinary case label.  */
3701       else if (high_bound
3702                && high_value
3703                && (tree_int_cst_compare ((tree) high_bound->key,
3704                                          high_value)
3705                    <= 0))
3706         node = high_bound;
3707     }
3708   /* If there was an overlap, issue an error.  */
3709   if (node)
3710     {
3711       tree duplicate = CASE_LABEL_DECL ((tree) node->value);
3712
3713       if (high_value)
3714         {
3715           error ("duplicate (or overlapping) case value");
3716           error_with_decl (duplicate,
3717                            "this is the first entry overlapping that value");
3718         }
3719       else if (low_value)
3720         {
3721           error ("duplicate case value") ;
3722           error_with_decl (duplicate, "previously used here");
3723         }
3724       else
3725         {
3726           error ("multiple default labels in one switch");
3727           error_with_decl (duplicate, "this is the first default label");
3728         }
3729       if (!cases->root)
3730         add_stmt (build_case_label (NULL_TREE, NULL_TREE, label));
3731     }
3732
3733   /* Add a CASE_LABEL to the statement-tree.  */
3734   case_label = add_stmt (build_case_label (low_value, high_value, label));
3735   /* Register this case label in the splay tree.  */
3736   splay_tree_insert (cases,
3737                      (splay_tree_key) low_value,
3738                      (splay_tree_value) case_label);
3739
3740   return case_label;
3741 }
3742
3743 /* Finish an expression taking the address of LABEL.  Returns an
3744    expression for the address.  */
3745
3746 tree
3747 finish_label_address_expr (label)
3748      tree label;
3749 {
3750   tree result;
3751
3752   if (pedantic)
3753     {
3754       if (c_language == clk_cplusplus)
3755         pedwarn ("ISO C++ forbids taking the address of a label");
3756       else
3757         pedwarn ("ISO C forbids taking the address of a label");
3758     }
3759
3760   label = lookup_label (label);
3761   if (label == NULL_TREE)
3762     result = null_pointer_node;
3763   else
3764     {
3765       TREE_USED (label) = 1;
3766       result = build1 (ADDR_EXPR, ptr_type_node, label);
3767       TREE_CONSTANT (result) = 1;
3768       /* The current function in not necessarily uninlinable.
3769          Computed gotos are incompatible with inlining, but the value
3770          here could be used only in a diagnostic, for example.  */
3771     }
3772
3773   return result;
3774 }
3775
3776 /* Hook used by expand_expr to expand language-specific tree codes.  */
3777
3778 rtx
3779 c_expand_expr (exp, target, tmode, modifier)
3780      tree exp;
3781      rtx target;
3782      enum machine_mode tmode;
3783      int modifier;  /* Actually enum_modifier.  */
3784 {
3785   switch (TREE_CODE (exp))
3786     {
3787     case STMT_EXPR:
3788       {
3789         tree rtl_expr;
3790         rtx result;
3791         bool preserve_result = false;
3792
3793         /* Since expand_expr_stmt calls free_temp_slots after every
3794            expression statement, we must call push_temp_slots here.
3795            Otherwise, any temporaries in use now would be considered
3796            out-of-scope after the first EXPR_STMT from within the
3797            STMT_EXPR.  */
3798         push_temp_slots ();
3799         rtl_expr = expand_start_stmt_expr (!STMT_EXPR_NO_SCOPE (exp));
3800
3801         /* If we want the result of this expression, find the last
3802            EXPR_STMT in the COMPOUND_STMT and mark it as addressable.  */
3803         if (target != const0_rtx
3804             && TREE_CODE (STMT_EXPR_STMT (exp)) == COMPOUND_STMT
3805             && TREE_CODE (COMPOUND_BODY (STMT_EXPR_STMT (exp))) == SCOPE_STMT)
3806           {
3807             tree expr = COMPOUND_BODY (STMT_EXPR_STMT (exp));
3808             tree last = TREE_CHAIN (expr);
3809
3810             while (TREE_CHAIN (last))
3811               {
3812                 expr = last;
3813                 last = TREE_CHAIN (last);
3814               }
3815
3816             if (TREE_CODE (last) == SCOPE_STMT
3817                 && TREE_CODE (expr) == EXPR_STMT)
3818               {
3819                 TREE_ADDRESSABLE (expr) = 1;
3820                 preserve_result = true;
3821               }
3822           }
3823
3824         expand_stmt (STMT_EXPR_STMT (exp));
3825         expand_end_stmt_expr (rtl_expr);
3826
3827         result = expand_expr (rtl_expr, target, tmode, modifier);
3828         if (preserve_result && GET_CODE (result) == MEM)
3829           {
3830             if (GET_MODE (result) != BLKmode)
3831               result = copy_to_reg (result);
3832             else
3833               preserve_temp_slots (result);
3834           }
3835
3836         /* If the statment-expression does not have a scope, then the
3837            new temporaries we created within it must live beyond the
3838            statement-expression.  */
3839         if (STMT_EXPR_NO_SCOPE (exp))
3840           preserve_temp_slots (NULL_RTX);
3841
3842         pop_temp_slots ();
3843         return result;
3844       }
3845       break;
3846
3847     case CALL_EXPR:
3848       {
3849         if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
3850             && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
3851                 == FUNCTION_DECL)
3852             && DECL_BUILT_IN (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
3853             && (DECL_BUILT_IN_CLASS (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
3854                 == BUILT_IN_FRONTEND))
3855           return c_expand_builtin (exp, target, tmode, modifier);
3856         else
3857           abort ();
3858       }
3859       break;
3860
3861     case COMPOUND_LITERAL_EXPR:
3862       {
3863         /* Initialize the anonymous variable declared in the compound
3864            literal, then return the variable.  */
3865         tree decl = COMPOUND_LITERAL_EXPR_DECL (exp);
3866         emit_local_var (decl);
3867         return expand_expr (decl, target, tmode, modifier);
3868       }
3869
3870     default:
3871       abort ();
3872     }
3873
3874   abort ();
3875   return NULL;
3876 }
3877
3878 /* Hook used by safe_from_p to handle language-specific tree codes.  */
3879
3880 int
3881 c_safe_from_p (target, exp)
3882      rtx target;
3883      tree exp;
3884 {
3885   /* We can see statements here when processing the body of a
3886      statement-expression.  For a declaration statement declaring a
3887      variable, look at the variable's initializer.  */
3888   if (TREE_CODE (exp) == DECL_STMT)
3889     {
3890       tree decl = DECL_STMT_DECL (exp);
3891
3892       if (TREE_CODE (decl) == VAR_DECL
3893           && DECL_INITIAL (decl)
3894           && !safe_from_p (target, DECL_INITIAL (decl), /*top_p=*/0))
3895         return 0;
3896     }
3897
3898   /* For any statement, we must follow the statement-chain.  */
3899   if (statement_code_p (TREE_CODE (exp)) && TREE_CHAIN (exp))
3900     return safe_from_p (target, TREE_CHAIN (exp), /*top_p=*/0);
3901
3902   /* Assume everything else is safe.  */
3903   return 1;
3904 }
3905
3906 /* Hook used by unsafe_for_reeval to handle language-specific tree codes.  */
3907
3908 int
3909 c_common_unsafe_for_reeval (exp)
3910      tree exp;
3911 {
3912   /* Statement expressions may not be reevaluated, likewise compound
3913      literals.  */
3914   if (TREE_CODE (exp) == STMT_EXPR
3915       || TREE_CODE (exp) == COMPOUND_LITERAL_EXPR)
3916     return 2;
3917
3918   /* Walk all other expressions.  */
3919   return -1;
3920 }
3921
3922 /* Hook used by staticp to handle language-specific tree codes.  */
3923
3924 int
3925 c_staticp (exp)
3926      tree exp;
3927 {
3928   if (TREE_CODE (exp) == COMPOUND_LITERAL_EXPR
3929       && TREE_STATIC (COMPOUND_LITERAL_EXPR_DECL (exp)))
3930     return 1;
3931   return 0;
3932 }
3933
3934 #define CALLED_AS_BUILT_IN(NODE) \
3935    (!strncmp (IDENTIFIER_POINTER (DECL_NAME (NODE)), "__builtin_", 10))
3936
3937 static rtx
3938 c_expand_builtin (exp, target, tmode, modifier)
3939      tree exp;
3940      rtx target;
3941      enum machine_mode tmode;
3942      enum expand_modifier modifier;
3943 {
3944   tree type = TREE_TYPE (exp);
3945   tree fndecl = TREE_OPERAND (TREE_OPERAND (exp, 0), 0);
3946   tree arglist = TREE_OPERAND (exp, 1);
3947   enum built_in_function fcode = DECL_FUNCTION_CODE (fndecl);
3948   enum tree_code code = TREE_CODE (exp);
3949   const int ignore = (target == const0_rtx
3950                       || ((code == NON_LVALUE_EXPR || code == NOP_EXPR
3951                            || code == CONVERT_EXPR || code == REFERENCE_EXPR
3952                            || code == COND_EXPR)
3953                           && TREE_CODE (type) == VOID_TYPE));
3954
3955   if (! optimize && ! CALLED_AS_BUILT_IN (fndecl))
3956     return expand_call (exp, target, ignore);
3957
3958   switch (fcode)
3959     {
3960     case BUILT_IN_PRINTF:
3961       target = c_expand_builtin_printf (arglist, target, tmode,
3962                                         modifier, ignore, /*unlocked=*/ 0);
3963       if (target)
3964         return target;
3965       break;
3966
3967     case BUILT_IN_PRINTF_UNLOCKED:
3968       target = c_expand_builtin_printf (arglist, target, tmode,
3969                                         modifier, ignore, /*unlocked=*/ 1);
3970       if (target)
3971         return target;
3972       break;
3973
3974     case BUILT_IN_FPRINTF:
3975       target = c_expand_builtin_fprintf (arglist, target, tmode,
3976                                          modifier, ignore, /*unlocked=*/ 0);
3977       if (target)
3978         return target;
3979       break;
3980
3981     case BUILT_IN_FPRINTF_UNLOCKED:
3982       target = c_expand_builtin_fprintf (arglist, target, tmode,
3983                                          modifier, ignore, /*unlocked=*/ 1);
3984       if (target)
3985         return target;
3986       break;
3987
3988     default:                    /* just do library call, if unknown builtin */
3989       error ("built-in function `%s' not currently supported",
3990              IDENTIFIER_POINTER (DECL_NAME (fndecl)));
3991     }
3992
3993   /* The switch statement above can drop through to cause the function
3994      to be called normally.  */
3995   return expand_call (exp, target, ignore);
3996 }
3997
3998 /* Check an arglist to *printf for problems.  The arglist should start
3999    at the format specifier, with the remaining arguments immediately
4000    following it.  */
4001 static int
4002 is_valid_printf_arglist (arglist)
4003      tree arglist;
4004 {
4005   /* Save this value so we can restore it later.  */
4006   const int SAVE_pedantic = pedantic;
4007   int diagnostic_occurred = 0;
4008   tree attrs;
4009
4010   /* Set this to a known value so the user setting won't affect code
4011      generation.  */
4012   pedantic = 1;
4013   /* Check to make sure there are no format specifier errors.  */
4014   attrs = tree_cons (get_identifier ("format"),
4015                      tree_cons (NULL_TREE,
4016                                 get_identifier ("printf"),
4017                                 tree_cons (NULL_TREE,
4018                                            integer_one_node,
4019                                            tree_cons (NULL_TREE,
4020                                                       build_int_2 (2, 0),
4021                                                       NULL_TREE))),
4022                      NULL_TREE);
4023   check_function_format (&diagnostic_occurred, attrs, arglist);
4024
4025   /* Restore the value of `pedantic'.  */
4026   pedantic = SAVE_pedantic;
4027
4028   /* If calling `check_function_format_ptr' produces a warning, we
4029      return false, otherwise we return true.  */
4030   return ! diagnostic_occurred;
4031 }
4032
4033 /* If the arguments passed to printf are suitable for optimizations,
4034    we attempt to transform the call.  */
4035 static rtx
4036 c_expand_builtin_printf (arglist, target, tmode, modifier, ignore, unlocked)
4037      tree arglist;
4038      rtx target;
4039      enum machine_mode tmode;
4040      enum expand_modifier modifier;
4041      int ignore;
4042      int unlocked;
4043 {
4044   tree fn_putchar = unlocked ?
4045     built_in_decls[BUILT_IN_PUTCHAR_UNLOCKED] : built_in_decls[BUILT_IN_PUTCHAR];
4046   tree fn_puts = unlocked ?
4047     built_in_decls[BUILT_IN_PUTS_UNLOCKED] : built_in_decls[BUILT_IN_PUTS];
4048   tree fn, format_arg, stripped_string;
4049
4050   /* If the return value is used, or the replacement _DECL isn't
4051      initialized, don't do the transformation.  */
4052   if (!ignore || !fn_putchar || !fn_puts)
4053     return 0;
4054
4055   /* Verify the required arguments in the original call.  */
4056   if (arglist == 0
4057       || (TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) != POINTER_TYPE))
4058     return 0;
4059
4060   /* Check the specifier vs. the parameters.  */
4061   if (!is_valid_printf_arglist (arglist))
4062     return 0;
4063
4064   format_arg = TREE_VALUE (arglist);
4065   stripped_string = format_arg;
4066   STRIP_NOPS (stripped_string);
4067   if (stripped_string && TREE_CODE (stripped_string) == ADDR_EXPR)
4068     stripped_string = TREE_OPERAND (stripped_string, 0);
4069
4070   /* If the format specifier isn't a STRING_CST, punt.  */
4071   if (TREE_CODE (stripped_string) != STRING_CST)
4072     return 0;
4073
4074   /* OK!  We can attempt optimization.  */
4075
4076   /* If the format specifier was "%s\n", call __builtin_puts(arg2).  */
4077   if (strcmp (TREE_STRING_POINTER (stripped_string), "%s\n") == 0)
4078     {
4079       arglist = TREE_CHAIN (arglist);
4080       fn = fn_puts;
4081     }
4082   /* If the format specifier was "%c", call __builtin_putchar (arg2).  */
4083   else if (strcmp (TREE_STRING_POINTER (stripped_string), "%c") == 0)
4084     {
4085       arglist = TREE_CHAIN (arglist);
4086       fn = fn_putchar;
4087     }
4088   else
4089     {
4090       /* We can't handle anything else with % args or %% ... yet.  */
4091       if (strchr (TREE_STRING_POINTER (stripped_string), '%'))
4092         return 0;
4093
4094       /* If the resulting constant string has a length of 1, call
4095          putchar.  Note, TREE_STRING_LENGTH includes the terminating
4096          NULL in its count.  */
4097       if (TREE_STRING_LENGTH (stripped_string) == 2)
4098         {
4099           /* Given printf("c"), (where c is any one character,)
4100              convert "c"[0] to an int and pass that to the replacement
4101              function.  */
4102           arglist = build_int_2 (TREE_STRING_POINTER (stripped_string)[0], 0);
4103           arglist = build_tree_list (NULL_TREE, arglist);
4104
4105           fn = fn_putchar;
4106         }
4107       /* If the resulting constant was "string\n", call
4108          __builtin_puts("string").  Ensure "string" has at least one
4109          character besides the trailing \n.  Note, TREE_STRING_LENGTH
4110          includes the terminating NULL in its count.  */
4111       else if (TREE_STRING_LENGTH (stripped_string) > 2
4112                && TREE_STRING_POINTER (stripped_string)
4113                [TREE_STRING_LENGTH (stripped_string) - 2] == '\n')
4114         {
4115           /* Create a NULL-terminated string that's one char shorter
4116              than the original, stripping off the trailing '\n'.  */
4117           const int newlen = TREE_STRING_LENGTH (stripped_string) - 1;
4118           char *newstr = (char *) alloca (newlen);
4119           memcpy (newstr, TREE_STRING_POINTER (stripped_string), newlen - 1);
4120           newstr[newlen - 1] = 0;
4121
4122           arglist = fix_string_type (build_string (newlen, newstr));
4123           arglist = build_tree_list (NULL_TREE, arglist);
4124           fn = fn_puts;
4125         }
4126       else
4127         /* We'd like to arrange to call fputs(string) here, but we
4128            need stdout and don't have a way to get it ... yet.  */
4129         return 0;
4130     }
4131
4132   return expand_expr (build_function_call (fn, arglist),
4133                       (ignore ? const0_rtx : target),
4134                       tmode, modifier);
4135 }
4136
4137 /* If the arguments passed to fprintf are suitable for optimizations,
4138    we attempt to transform the call.  */
4139 static rtx
4140 c_expand_builtin_fprintf (arglist, target, tmode, modifier, ignore, unlocked)
4141      tree arglist;
4142      rtx target;
4143      enum machine_mode tmode;
4144      enum expand_modifier modifier;
4145      int ignore;
4146      int unlocked;
4147 {
4148   tree fn_fputc = unlocked ?
4149     built_in_decls[BUILT_IN_FPUTC_UNLOCKED] : built_in_decls[BUILT_IN_FPUTC];
4150   tree fn_fputs = unlocked ?
4151     built_in_decls[BUILT_IN_FPUTS_UNLOCKED] : built_in_decls[BUILT_IN_FPUTS];
4152   tree fn, format_arg, stripped_string;
4153
4154   /* If the return value is used, or the replacement _DECL isn't
4155      initialized, don't do the transformation.  */
4156   if (!ignore || !fn_fputc || !fn_fputs)
4157     return 0;
4158
4159   /* Verify the required arguments in the original call.  */
4160   if (arglist == 0
4161       || (TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) != POINTER_TYPE)
4162       || (TREE_CHAIN (arglist) == 0)
4163       || (TREE_CODE (TREE_TYPE (TREE_VALUE (TREE_CHAIN (arglist)))) !=
4164           POINTER_TYPE))
4165     return 0;
4166
4167   /* Check the specifier vs. the parameters.  */
4168   if (!is_valid_printf_arglist (TREE_CHAIN (arglist)))
4169     return 0;
4170
4171   format_arg = TREE_VALUE (TREE_CHAIN (arglist));
4172   stripped_string = format_arg;
4173   STRIP_NOPS (stripped_string);
4174   if (stripped_string && TREE_CODE (stripped_string) == ADDR_EXPR)
4175     stripped_string = TREE_OPERAND (stripped_string, 0);
4176
4177   /* If the format specifier isn't a STRING_CST, punt.  */
4178   if (TREE_CODE (stripped_string) != STRING_CST)
4179     return 0;
4180
4181   /* OK!  We can attempt optimization.  */
4182
4183   /* If the format specifier was "%s", call __builtin_fputs(arg3, arg1).  */
4184   if (strcmp (TREE_STRING_POINTER (stripped_string), "%s") == 0)
4185     {
4186       tree newarglist = build_tree_list (NULL_TREE, TREE_VALUE (arglist));
4187       arglist = tree_cons (NULL_TREE,
4188                            TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist))),
4189                            newarglist);
4190       fn = fn_fputs;
4191     }
4192   /* If the format specifier was "%c", call __builtin_fputc (arg3, arg1).  */
4193   else if (strcmp (TREE_STRING_POINTER (stripped_string), "%c") == 0)
4194     {
4195       tree newarglist = build_tree_list (NULL_TREE, TREE_VALUE (arglist));
4196       arglist = tree_cons (NULL_TREE,
4197                            TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist))),
4198                            newarglist);
4199       fn = fn_fputc;
4200     }
4201   else
4202     {
4203       /* We can't handle anything else with % args or %% ... yet.  */
4204       if (strchr (TREE_STRING_POINTER (stripped_string), '%'))
4205         return 0;
4206
4207       /* When "string" doesn't contain %, replace all cases of
4208          fprintf(stream,string) with fputs(string,stream).  The fputs
4209          builtin will take take of special cases like length==1.  */
4210       arglist = tree_cons (NULL_TREE, TREE_VALUE (TREE_CHAIN (arglist)),
4211                            build_tree_list (NULL_TREE, TREE_VALUE (arglist)));
4212       fn = fn_fputs;
4213     }
4214
4215   return expand_expr (build_function_call (fn, arglist),
4216                       (ignore ? const0_rtx : target),
4217                       tmode, modifier);
4218 }
4219 \f
4220
4221 /* Given a boolean expression ARG, return a tree representing an increment
4222    or decrement (as indicated by CODE) of ARG.  The front end must check for
4223    invalid cases (e.g., decrement in C++).  */
4224 tree
4225 boolean_increment (code, arg)
4226      enum tree_code code;
4227      tree arg;
4228 {
4229   tree val;
4230   tree true_res = (c_language == clk_cplusplus
4231                    ? boolean_true_node
4232                    : c_bool_true_node);
4233   arg = stabilize_reference (arg);
4234   switch (code)
4235     {
4236     case PREINCREMENT_EXPR:
4237       val = build (MODIFY_EXPR, TREE_TYPE (arg), arg, true_res);
4238       break;
4239     case POSTINCREMENT_EXPR:
4240       val = build (MODIFY_EXPR, TREE_TYPE (arg), arg, true_res);
4241       arg = save_expr (arg);
4242       val = build (COMPOUND_EXPR, TREE_TYPE (arg), val, arg);
4243       val = build (COMPOUND_EXPR, TREE_TYPE (arg), arg, val);
4244       break;
4245     case PREDECREMENT_EXPR:
4246       val = build (MODIFY_EXPR, TREE_TYPE (arg), arg, invert_truthvalue (arg));
4247       break;
4248     case POSTDECREMENT_EXPR:
4249       val = build (MODIFY_EXPR, TREE_TYPE (arg), arg, invert_truthvalue (arg));
4250       arg = save_expr (arg);
4251       val = build (COMPOUND_EXPR, TREE_TYPE (arg), val, arg);
4252       val = build (COMPOUND_EXPR, TREE_TYPE (arg), arg, val);
4253       break;
4254     default:
4255       abort ();
4256     }
4257   TREE_SIDE_EFFECTS (val) = 1;
4258   return val;
4259 }
4260 \f
4261 /* Common initialization before parsing options.  */
4262 void
4263 c_common_init_options (lang)
4264      enum c_language_kind lang;
4265 {
4266   c_language = lang;
4267   parse_in = cpp_create_reader (lang == clk_c || lang == clk_objective_c
4268                                 ? CLK_GNUC89 : CLK_GNUCXX);
4269   if (lang == clk_objective_c)
4270     cpp_get_options (parse_in)->objc = 1;
4271
4272   /* Mark as "unspecified" (see c_common_post_options).  */
4273   flag_bounds_check = -1;
4274 }
4275
4276 /* Post-switch processing.  */
4277 bool
4278 c_common_post_options ()
4279 {
4280   cpp_post_options (parse_in);
4281
4282   flag_inline_trees = 1;
4283
4284   /* Use tree inlining if possible.  Function instrumentation is only
4285      done in the RTL level, so we disable tree inlining.  */
4286   if (! flag_instrument_function_entry_exit)
4287     {
4288       if (!flag_no_inline)
4289         flag_no_inline = 1;
4290       if (flag_inline_functions)
4291         {
4292           flag_inline_trees = 2;
4293           flag_inline_functions = 0;
4294         }
4295     }
4296
4297   /* If still "unspecified", make it match -fbounded-pointers.  */
4298   if (flag_bounds_check == -1)
4299     flag_bounds_check = flag_bounded_pointers;
4300
4301   /* Special format checking options don't work without -Wformat; warn if
4302      they are used.  */
4303   if (warn_format_y2k && !warn_format)
4304     warning ("-Wformat-y2k ignored without -Wformat");
4305   if (warn_format_extra_args && !warn_format)
4306     warning ("-Wformat-extra-args ignored without -Wformat");
4307   if (warn_format_zero_length && !warn_format)
4308     warning ("-Wformat-zero-length ignored without -Wformat");
4309   if (warn_format_nonliteral && !warn_format)
4310     warning ("-Wformat-nonliteral ignored without -Wformat");
4311   if (warn_format_security && !warn_format)
4312     warning ("-Wformat-security ignored without -Wformat");
4313   if (warn_missing_format_attribute && !warn_format)
4314     warning ("-Wmissing-format-attribute ignored without -Wformat");
4315
4316   /* If an error has occurred in cpplib, note it so we fail
4317      immediately.  */
4318   errorcount += cpp_errors (parse_in);
4319
4320   return flag_preprocess_only;
4321 }
4322
4323 /* Hook that registers front end and target-specific built-ins.  */
4324 static void
4325 cb_register_builtins (pfile)
4326      cpp_reader *pfile;
4327 {
4328   /* -undef turns off target-specific built-ins.  */
4329   if (flag_undef)
4330     return;
4331
4332   if (c_language == clk_cplusplus)
4333     {
4334       if (SUPPORTS_ONE_ONLY)
4335         cpp_define (pfile, "__GXX_WEAK__=1");
4336       else
4337         cpp_define (pfile, "__GXX_WEAK__=0");
4338     }
4339
4340   /* libgcc needs to know this.  */
4341   if (USING_SJLJ_EXCEPTIONS)
4342     cpp_define (pfile, "__USING_SJLJ_EXCEPTIONS__");
4343
4344   /* stddef.h needs to know these.  */
4345   builtin_define_with_value ("__SIZE_TYPE__", SIZE_TYPE, 0);
4346   builtin_define_with_value ("__PTRDIFF_TYPE__", PTRDIFF_TYPE, 0);
4347   builtin_define_with_value ("__WCHAR_TYPE__", MODIFIED_WCHAR_TYPE, 0);
4348   builtin_define_with_value ("__WINT_TYPE__", WINT_TYPE, 0);
4349
4350   /* limits.h needs to know these.  */
4351   builtin_define_type_max ("__SCHAR_MAX__", signed_char_type_node, 0);
4352   builtin_define_type_max ("__SHRT_MAX__", short_integer_type_node, 0);
4353   builtin_define_type_max ("__INT_MAX__", integer_type_node, 0);
4354   builtin_define_type_max ("__LONG_MAX__", long_integer_type_node, 1);
4355   builtin_define_type_max ("__LONG_LONG_MAX__", long_long_integer_type_node, 2);
4356
4357   {
4358     char buf[8];
4359     sprintf (buf, "%d", (int) TYPE_PRECISION (signed_char_type_node));
4360     builtin_define_with_value ("__CHAR_BIT__", buf, 0);
4361   }
4362
4363   /* For use in assembly language.  */
4364   builtin_define_with_value ("__REGISTER_PREFIX__", REGISTER_PREFIX, 0);
4365   builtin_define_with_value ("__USER_LABEL_PREFIX__", user_label_prefix, 0);
4366
4367   /* Misc.  */
4368   builtin_define_with_value ("__VERSION__", version_string, 1);
4369
4370   /* Other target-independent built-ins determined by command-line
4371      options.  */
4372   if (optimize_size)
4373     cpp_define (pfile, "__OPTIMIZE_SIZE__");
4374   if (optimize)
4375     cpp_define (pfile, "__OPTIMIZE__");
4376
4377   if (flag_hosted)
4378     cpp_define (pfile, "__STDC_HOSTED__=1");
4379   else
4380     cpp_define (pfile, "__STDC_HOSTED__=0");
4381
4382   if (fast_math_flags_set_p ())
4383     cpp_define (pfile, "__FAST_MATH__");
4384   if (flag_no_inline)
4385     cpp_define (pfile, "__NO_INLINE__");
4386   if (flag_signaling_nans)
4387     cpp_define (pfile, "__SUPPORT_SNAN__");
4388   if (flag_finite_math_only)
4389     cpp_define (pfile, "__FINITE_MATH_ONLY__");
4390
4391   if (flag_iso)
4392     cpp_define (pfile, "__STRICT_ANSI__");
4393
4394   if (!flag_signed_char)
4395     cpp_define (pfile, "__CHAR_UNSIGNED__");
4396
4397   /* A straightforward target hook doesn't work, because of problems
4398      linking that hook's body when part of non-C front ends.  */
4399 # define preprocessing_asm_p() (cpp_get_options (pfile)->lang == CLK_ASM)
4400 # define builtin_define(TXT) cpp_define (pfile, TXT)
4401 # define builtin_assert(TXT) cpp_assert (pfile, TXT)
4402   TARGET_CPU_CPP_BUILTINS ();
4403   TARGET_OS_CPP_BUILTINS ();
4404 }
4405
4406 /* Pass an object-like macro.  If it doesn't lie in the user's
4407    namespace, defines it unconditionally.  Otherwise define a version
4408    with two leading underscores, and another version with two leading
4409    and trailing underscores, and define the original only if an ISO
4410    standard was not nominated.
4411
4412    e.g. passing "unix" defines "__unix", "__unix__" and possibly
4413    "unix".  Passing "_mips" defines "__mips", "__mips__" and possibly
4414    "_mips".  */
4415 void
4416 builtin_define_std (macro)
4417      const char *macro;
4418 {
4419   size_t len = strlen (macro);
4420   char *buff = alloca (len + 5);
4421   char *p = buff + 2;
4422   char *q = p + len;
4423
4424   /* prepend __ (or maybe just _) if in user's namespace.  */
4425   memcpy (p, macro, len + 1);
4426   if (!( *p == '_' && (p[1] == '_' || ISUPPER (p[1]))))
4427     {
4428       if (*p != '_')
4429         *--p = '_';
4430       if (p[1] != '_')
4431         *--p = '_';
4432     }
4433   cpp_define (parse_in, p);
4434
4435   /* If it was in user's namespace...  */
4436   if (p != buff + 2)
4437     {
4438       /* Define the macro with leading and following __.  */
4439       if (q[-1] != '_')
4440         *q++ = '_';
4441       if (q[-2] != '_')
4442         *q++ = '_';
4443       *q = '\0';
4444       cpp_define (parse_in, p);
4445
4446       /* Finally, define the original macro if permitted.  */
4447       if (!flag_iso)
4448         cpp_define (parse_in, macro);
4449     }
4450 }
4451
4452 /* Pass an object-like macro and a value to define it to.  The third
4453    parameter says whether or not to turn the value into a string
4454    constant.  */
4455 static void
4456 builtin_define_with_value (macro, expansion, is_str)
4457      const char *macro;
4458      const char *expansion;
4459      int is_str;
4460 {
4461   char *buf;
4462   size_t mlen = strlen (macro);
4463   size_t elen = strlen (expansion);
4464   size_t extra = 2;  /* space for an = and a NUL */
4465
4466   if (is_str)
4467     extra += 2;  /* space for two quote marks */
4468
4469   buf = alloca (mlen + elen + extra);
4470   if (is_str)
4471     sprintf (buf, "%s=\"%s\"", macro, expansion);
4472   else
4473     sprintf (buf, "%s=%s", macro, expansion);
4474
4475   cpp_define (parse_in, buf);
4476 }
4477
4478 /* Define MAX for TYPE based on the precision of the type, which is assumed
4479    to be signed.  IS_LONG is 1 for type "long" and 2 for "long long".  */
4480
4481 static void
4482 builtin_define_type_max (macro, type, is_long)
4483      const char *macro;
4484      tree type;
4485      int is_long;
4486 {
4487   const char *value;
4488   char *buf;
4489   size_t mlen, vlen, extra;
4490
4491   /* Pre-rendering the values mean we don't have to futz with printing a
4492      multi-word decimal value.  There are also a very limited number of
4493      precisions that we support, so it's really a waste of time.  */
4494   switch (TYPE_PRECISION (type))
4495     {
4496     case 8:
4497       value = "127";
4498       break;
4499     case 16:
4500       value = "32767";
4501       break;
4502     case 32:
4503       value = "2147483647";
4504       break;
4505     case 64:
4506       value = "9223372036854775807";
4507       break;
4508     case 128:
4509       value = "170141183460469231731687303715884105727";
4510       break;
4511     default:
4512       abort ();
4513     }
4514
4515   mlen = strlen (macro);
4516   vlen = strlen (value);
4517   extra = 2 + is_long;
4518   buf = alloca (mlen + vlen + extra);
4519
4520   sprintf (buf, "%s=%s%s", macro, value,
4521            (is_long == 1 ? "L" : is_long == 2 ? "LL" : ""));
4522
4523   cpp_define (parse_in, buf);
4524 }
4525
4526 /* Front end initialization common to C, ObjC and C++.  */
4527 const char *
4528 c_common_init (filename)
4529      const char *filename;
4530 {
4531   cpp_options *options = cpp_get_options (parse_in);
4532
4533   /* Set up preprocessor arithmetic.  Must be done after call to
4534      c_common_nodes_and_builtins for wchar_type_node to be good.  */
4535   options->precision = TYPE_PRECISION (intmax_type_node);
4536   options->char_precision = TYPE_PRECISION (char_type_node);
4537   options->int_precision = TYPE_PRECISION (integer_type_node);
4538   options->wchar_precision = TYPE_PRECISION (wchar_type_node);
4539   options->unsigned_wchar = TREE_UNSIGNED (wchar_type_node);
4540   options->unsigned_char = !flag_signed_char;
4541   options->warn_multichar = warn_multichar;
4542   options->stdc_0_in_system_headers = STDC_0_IN_SYSTEM_HEADERS;
4543
4544   /* We want -Wno-long-long to override -pedantic -std=non-c99
4545      whatever the ordering.  */
4546   options->warn_long_long = warn_long_long && !flag_isoc99 && pedantic;
4547
4548   /* Register preprocessor built-ins before calls to
4549      cpp_main_file.  */
4550   cpp_get_callbacks (parse_in)->register_builtins = cb_register_builtins;
4551
4552   /* NULL is passed up to toplev.c and we exit quickly.  */
4553   if (flag_preprocess_only)
4554     {
4555       cpp_preprocess_file (parse_in);
4556       return NULL;
4557     }
4558
4559   /* Do this before initializing pragmas, as then cpplib's hash table
4560      has been set up.  */
4561   filename = init_c_lex (filename);
4562
4563   init_pragma ();
4564
4565   if (!c_attrs_initialized)
4566     c_init_attributes ();
4567
4568   return filename;
4569 }
4570
4571 /* Common finish hook for the C, ObjC and C++ front ends.  */
4572 void
4573 c_common_finish ()
4574 {
4575   cpp_finish (parse_in);
4576
4577   /* For performance, avoid tearing down cpplib's internal structures.
4578      Call cpp_errors () instead of cpp_destroy ().  */
4579   errorcount += cpp_errors (parse_in);
4580 }
4581
4582 static void
4583 c_init_attributes ()
4584 {
4585   /* Fill in the built_in_attributes array.  */
4586 #define DEF_ATTR_NULL_TREE(ENUM)                \
4587   built_in_attributes[(int) ENUM] = NULL_TREE;
4588 #define DEF_ATTR_INT(ENUM, VALUE)                                            \
4589   built_in_attributes[(int) ENUM] = build_int_2 (VALUE, VALUE < 0 ? -1 : 0);
4590 #define DEF_ATTR_IDENT(ENUM, STRING)                            \
4591   built_in_attributes[(int) ENUM] = get_identifier (STRING);
4592 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) \
4593   built_in_attributes[(int) ENUM]                       \
4594     = tree_cons (built_in_attributes[(int) PURPOSE],    \
4595                  built_in_attributes[(int) VALUE],      \
4596                  built_in_attributes[(int) CHAIN]);
4597 #define DEF_FN_ATTR(NAME, ATTRS, PREDICATE) /* No initialization needed.  */
4598 #include "builtin-attrs.def"
4599 #undef DEF_ATTR_NULL_TREE
4600 #undef DEF_ATTR_INT
4601 #undef DEF_ATTR_IDENT
4602 #undef DEF_ATTR_TREE_LIST
4603 #undef DEF_FN_ATTR
4604   c_attrs_initialized = true;
4605 }
4606
4607 /* Depending on the name of DECL, apply default attributes to it.  */
4608
4609 void
4610 c_common_insert_default_attributes (decl)
4611      tree decl;
4612 {
4613   tree name = DECL_NAME (decl);
4614
4615   if (!c_attrs_initialized)
4616     c_init_attributes ();
4617
4618 #define DEF_ATTR_NULL_TREE(ENUM) /* Nothing needed after initialization.  */
4619 #define DEF_ATTR_INT(ENUM, VALUE)
4620 #define DEF_ATTR_IDENT(ENUM, STRING)
4621 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN)
4622 #define DEF_FN_ATTR(NAME, ATTRS, PREDICATE)                     \
4623   if ((PREDICATE) && name == built_in_attributes[(int) NAME])   \
4624     decl_attributes (&decl, built_in_attributes[(int) ATTRS],   \
4625                      ATTR_FLAG_BUILT_IN);
4626 #include "builtin-attrs.def"
4627 #undef DEF_ATTR_NULL_TREE
4628 #undef DEF_ATTR_INT
4629 #undef DEF_ATTR_IDENT
4630 #undef DEF_ATTR_TREE_LIST
4631 #undef DEF_FN_ATTR
4632 }
4633
4634 /* Output a -Wshadow warning MSGID about NAME, an IDENTIFIER_NODE, and
4635    additionally give the location of the previous declaration DECL.  */
4636 void
4637 shadow_warning (msgid, name, decl)
4638      const char *msgid;
4639      tree name, decl;
4640 {
4641   warning ("declaration of `%s' shadows %s", IDENTIFIER_POINTER (name), msgid);
4642   warning_with_file_and_line (DECL_SOURCE_FILE (decl),
4643                               DECL_SOURCE_LINE (decl),
4644                               "shadowed declaration is here");
4645 }
4646
4647 /* Attribute handlers common to C front ends.  */
4648
4649 /* Handle a "packed" attribute; arguments as in
4650    struct attribute_spec.handler.  */
4651
4652 static tree
4653 handle_packed_attribute (node, name, args, flags, no_add_attrs)
4654      tree *node;
4655      tree name;
4656      tree args ATTRIBUTE_UNUSED;
4657      int flags;
4658      bool *no_add_attrs;
4659 {
4660   tree *type = NULL;
4661   if (DECL_P (*node))
4662     {
4663       if (TREE_CODE (*node) == TYPE_DECL)
4664         type = &TREE_TYPE (*node);
4665     }
4666   else
4667     type = node;
4668
4669   if (type)
4670     {
4671       if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
4672         *type = build_type_copy (*type);
4673       TYPE_PACKED (*type) = 1;
4674     }
4675   else if (TREE_CODE (*node) == FIELD_DECL)
4676     DECL_PACKED (*node) = 1;
4677   /* We can't set DECL_PACKED for a VAR_DECL, because the bit is
4678      used for DECL_REGISTER.  It wouldn't mean anything anyway.  */
4679   else
4680     {
4681       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4682       *no_add_attrs = true;
4683     }
4684
4685   return NULL_TREE;
4686 }
4687
4688 /* Handle a "nocommon" attribute; arguments as in
4689    struct attribute_spec.handler.  */
4690
4691 static tree
4692 handle_nocommon_attribute (node, name, args, flags, no_add_attrs)
4693      tree *node;
4694      tree name;
4695      tree args ATTRIBUTE_UNUSED;
4696      int flags ATTRIBUTE_UNUSED;
4697      bool *no_add_attrs;
4698 {
4699   if (TREE_CODE (*node) == VAR_DECL)
4700     DECL_COMMON (*node) = 0;
4701   else
4702     {
4703       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4704       *no_add_attrs = true;
4705     }
4706
4707   return NULL_TREE;
4708 }
4709
4710 /* Handle a "common" attribute; arguments as in
4711    struct attribute_spec.handler.  */
4712
4713 static tree
4714 handle_common_attribute (node, name, args, flags, no_add_attrs)
4715      tree *node;
4716      tree name;
4717      tree args ATTRIBUTE_UNUSED;
4718      int flags ATTRIBUTE_UNUSED;
4719      bool *no_add_attrs;
4720 {
4721   if (TREE_CODE (*node) == VAR_DECL)
4722     DECL_COMMON (*node) = 1;
4723   else
4724     {
4725       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4726       *no_add_attrs = true;
4727     }
4728
4729   return NULL_TREE;
4730 }
4731
4732 /* Handle a "noreturn" attribute; arguments as in
4733    struct attribute_spec.handler.  */
4734
4735 static tree
4736 handle_noreturn_attribute (node, name, args, flags, no_add_attrs)
4737      tree *node;
4738      tree name;
4739      tree args ATTRIBUTE_UNUSED;
4740      int flags ATTRIBUTE_UNUSED;
4741      bool *no_add_attrs;
4742 {
4743   tree type = TREE_TYPE (*node);
4744
4745   /* See FIXME comment in c_common_attribute_table.  */
4746   if (TREE_CODE (*node) == FUNCTION_DECL)
4747     TREE_THIS_VOLATILE (*node) = 1;
4748   else if (TREE_CODE (type) == POINTER_TYPE
4749            && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
4750     TREE_TYPE (*node)
4751       = build_pointer_type
4752         (build_type_variant (TREE_TYPE (type),
4753                              TREE_READONLY (TREE_TYPE (type)), 1));
4754   else
4755     {
4756       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4757       *no_add_attrs = true;
4758     }
4759
4760   return NULL_TREE;
4761 }
4762
4763 /* Handle a "noinline" attribute; arguments as in
4764    struct attribute_spec.handler.  */
4765
4766 static tree
4767 handle_noinline_attribute (node, name, args, flags, no_add_attrs)
4768      tree *node;
4769      tree name;
4770      tree args ATTRIBUTE_UNUSED;
4771      int flags ATTRIBUTE_UNUSED;
4772      bool *no_add_attrs;
4773 {
4774   if (TREE_CODE (*node) == FUNCTION_DECL)
4775     DECL_UNINLINABLE (*node) = 1;
4776   else
4777     {
4778       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4779       *no_add_attrs = true;
4780     }
4781
4782   return NULL_TREE;
4783 }
4784
4785 /* Handle a "always_inline" attribute; arguments as in
4786    struct attribute_spec.handler.  */
4787
4788 static tree
4789 handle_always_inline_attribute (node, name, args, flags, no_add_attrs)
4790      tree *node;
4791      tree name;
4792      tree args ATTRIBUTE_UNUSED;
4793      int flags ATTRIBUTE_UNUSED;
4794      bool *no_add_attrs;
4795 {
4796   if (TREE_CODE (*node) == FUNCTION_DECL)
4797     {
4798       /* Do nothing else, just set the attribute.  We'll get at
4799          it later with lookup_attribute.  */
4800     }
4801   else
4802     {
4803       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4804       *no_add_attrs = true;
4805     }
4806
4807   return NULL_TREE;
4808 }
4809
4810 /* Handle a "used" attribute; arguments as in
4811    struct attribute_spec.handler.  */
4812
4813 static tree
4814 handle_used_attribute (node, name, args, flags, no_add_attrs)
4815      tree *node;
4816      tree name;
4817      tree args ATTRIBUTE_UNUSED;
4818      int flags ATTRIBUTE_UNUSED;
4819      bool *no_add_attrs;
4820 {
4821   if (TREE_CODE (*node) == FUNCTION_DECL)
4822     TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (*node))
4823       = TREE_USED (*node) = 1;
4824   else
4825     {
4826       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4827       *no_add_attrs = true;
4828     }
4829
4830   return NULL_TREE;
4831 }
4832
4833 /* Handle a "unused" attribute; arguments as in
4834    struct attribute_spec.handler.  */
4835
4836 static tree
4837 handle_unused_attribute (node, name, args, flags, no_add_attrs)
4838      tree *node;
4839      tree name;
4840      tree args ATTRIBUTE_UNUSED;
4841      int flags;
4842      bool *no_add_attrs;
4843 {
4844   if (DECL_P (*node))
4845     {
4846       tree decl = *node;
4847
4848       if (TREE_CODE (decl) == PARM_DECL
4849           || TREE_CODE (decl) == VAR_DECL
4850           || TREE_CODE (decl) == FUNCTION_DECL
4851           || TREE_CODE (decl) == LABEL_DECL
4852           || TREE_CODE (decl) == TYPE_DECL)
4853         TREE_USED (decl) = 1;
4854       else
4855         {
4856           warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4857           *no_add_attrs = true;
4858         }
4859     }
4860   else
4861     {
4862       if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
4863         *node = build_type_copy (*node);
4864       TREE_USED (*node) = 1;
4865     }
4866
4867   return NULL_TREE;
4868 }
4869
4870 /* Handle a "const" attribute; arguments as in
4871    struct attribute_spec.handler.  */
4872
4873 static tree
4874 handle_const_attribute (node, name, args, flags, no_add_attrs)
4875      tree *node;
4876      tree name;
4877      tree args ATTRIBUTE_UNUSED;
4878      int flags ATTRIBUTE_UNUSED;
4879      bool *no_add_attrs;
4880 {
4881   tree type = TREE_TYPE (*node);
4882
4883   /* See FIXME comment on noreturn in c_common_attribute_table.  */
4884   if (TREE_CODE (*node) == FUNCTION_DECL)
4885     TREE_READONLY (*node) = 1;
4886   else if (TREE_CODE (type) == POINTER_TYPE
4887            && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
4888     TREE_TYPE (*node)
4889       = build_pointer_type
4890         (build_type_variant (TREE_TYPE (type), 1,
4891                              TREE_THIS_VOLATILE (TREE_TYPE (type))));
4892   else
4893     {
4894       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4895       *no_add_attrs = true;
4896     }
4897
4898   return NULL_TREE;
4899 }
4900
4901 /* Handle a "transparent_union" attribute; arguments as in
4902    struct attribute_spec.handler.  */
4903
4904 static tree
4905 handle_transparent_union_attribute (node, name, args, flags, no_add_attrs)
4906      tree *node;
4907      tree name;
4908      tree args ATTRIBUTE_UNUSED;
4909      int flags;
4910      bool *no_add_attrs;
4911 {
4912   tree decl = NULL_TREE;
4913   tree *type = NULL;
4914   int is_type = 0;
4915
4916   if (DECL_P (*node))
4917     {
4918       decl = *node;
4919       type = &TREE_TYPE (decl);
4920       is_type = TREE_CODE (*node) == TYPE_DECL;
4921     }
4922   else if (TYPE_P (*node))
4923     type = node, is_type = 1;
4924
4925   if (is_type
4926       && TREE_CODE (*type) == UNION_TYPE
4927       && (decl == 0
4928           || (TYPE_FIELDS (*type) != 0
4929               && TYPE_MODE (*type) == DECL_MODE (TYPE_FIELDS (*type)))))
4930     {
4931       if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
4932         *type = build_type_copy (*type);
4933       TYPE_TRANSPARENT_UNION (*type) = 1;
4934     }
4935   else if (decl != 0 && TREE_CODE (decl) == PARM_DECL
4936            && TREE_CODE (*type) == UNION_TYPE
4937            && TYPE_MODE (*type) == DECL_MODE (TYPE_FIELDS (*type)))
4938     DECL_TRANSPARENT_UNION (decl) = 1;
4939   else
4940     {
4941       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4942       *no_add_attrs = true;
4943     }
4944
4945   return NULL_TREE;
4946 }
4947
4948 /* Handle a "constructor" attribute; arguments as in
4949    struct attribute_spec.handler.  */
4950
4951 static tree
4952 handle_constructor_attribute (node, name, args, flags, no_add_attrs)
4953      tree *node;
4954      tree name;
4955      tree args ATTRIBUTE_UNUSED;
4956      int flags ATTRIBUTE_UNUSED;
4957      bool *no_add_attrs;
4958 {
4959   tree decl = *node;
4960   tree type = TREE_TYPE (decl);
4961
4962   if (TREE_CODE (decl) == FUNCTION_DECL
4963       && TREE_CODE (type) == FUNCTION_TYPE
4964       && decl_function_context (decl) == 0)
4965     {
4966       DECL_STATIC_CONSTRUCTOR (decl) = 1;
4967       TREE_USED (decl) = 1;
4968     }
4969   else
4970     {
4971       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4972       *no_add_attrs = true;
4973     }
4974
4975   return NULL_TREE;
4976 }
4977
4978 /* Handle a "destructor" attribute; arguments as in
4979    struct attribute_spec.handler.  */
4980
4981 static tree
4982 handle_destructor_attribute (node, name, args, flags, no_add_attrs)
4983      tree *node;
4984      tree name;
4985      tree args ATTRIBUTE_UNUSED;
4986      int flags ATTRIBUTE_UNUSED;
4987      bool *no_add_attrs;
4988 {
4989   tree decl = *node;
4990   tree type = TREE_TYPE (decl);
4991
4992   if (TREE_CODE (decl) == FUNCTION_DECL
4993       && TREE_CODE (type) == FUNCTION_TYPE
4994       && decl_function_context (decl) == 0)
4995     {
4996       DECL_STATIC_DESTRUCTOR (decl) = 1;
4997       TREE_USED (decl) = 1;
4998     }
4999   else
5000     {
5001       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
5002       *no_add_attrs = true;
5003     }
5004
5005   return NULL_TREE;
5006 }
5007
5008 /* Handle a "mode" attribute; arguments as in
5009    struct attribute_spec.handler.  */
5010
5011 static tree
5012 handle_mode_attribute (node, name, args, flags, no_add_attrs)
5013      tree *node;
5014      tree name;
5015      tree args;
5016      int flags ATTRIBUTE_UNUSED;
5017      bool *no_add_attrs;
5018 {
5019   tree type = *node;
5020
5021   *no_add_attrs = true;
5022
5023   if (TREE_CODE (TREE_VALUE (args)) != IDENTIFIER_NODE)
5024     warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
5025   else
5026     {
5027       int j;
5028       const char *p = IDENTIFIER_POINTER (TREE_VALUE (args));
5029       int len = strlen (p);
5030       enum machine_mode mode = VOIDmode;
5031       tree typefm;
5032
5033       if (len > 4 && p[0] == '_' && p[1] == '_'
5034           && p[len - 1] == '_' && p[len - 2] == '_')
5035         {
5036           char *newp = (char *) alloca (len - 1);
5037
5038           strcpy (newp, &p[2]);
5039           newp[len - 4] = '\0';
5040           p = newp;
5041         }
5042
5043       /* Change this type to have a type with the specified mode.
5044          First check for the special modes.  */
5045       if (! strcmp (p, "byte"))
5046         mode = byte_mode;
5047       else if (!strcmp (p, "word"))
5048         mode = word_mode;
5049       else if (! strcmp (p, "pointer"))
5050         mode = ptr_mode;
5051       else
5052         for (j = 0; j < NUM_MACHINE_MODES; j++)
5053           if (!strcmp (p, GET_MODE_NAME (j)))
5054             mode = (enum machine_mode) j;
5055
5056       if (mode == VOIDmode)
5057         error ("unknown machine mode `%s'", p);
5058       else if (0 == (typefm = (*lang_hooks.types.type_for_mode)
5059                      (mode, TREE_UNSIGNED (type))))
5060         error ("no data type for mode `%s'", p);
5061       else
5062         {
5063           /* If this is a vector, make sure we either have hardware
5064              support, or we can emulate it.  */
5065           if ((GET_MODE_CLASS (mode) == MODE_VECTOR_INT
5066                || GET_MODE_CLASS (mode) == MODE_VECTOR_FLOAT)
5067               && !vector_mode_valid_p (mode))
5068             {
5069               error ("unable to emulate '%s'", GET_MODE_NAME (mode));
5070               return NULL_TREE;
5071             }
5072
5073           *node = typefm;
5074           /* No need to layout the type here.  The caller should do this.  */
5075         }
5076     }
5077
5078   return NULL_TREE;
5079 }
5080
5081 /* Handle a "section" attribute; arguments as in
5082    struct attribute_spec.handler.  */
5083
5084 static tree
5085 handle_section_attribute (node, name, args, flags, no_add_attrs)
5086      tree *node;
5087      tree name ATTRIBUTE_UNUSED;
5088      tree args;
5089      int flags ATTRIBUTE_UNUSED;
5090      bool *no_add_attrs;
5091 {
5092   tree decl = *node;
5093
5094   if (targetm.have_named_sections)
5095     {
5096       if ((TREE_CODE (decl) == FUNCTION_DECL
5097            || TREE_CODE (decl) == VAR_DECL)
5098           && TREE_CODE (TREE_VALUE (args)) == STRING_CST)
5099         {
5100           if (TREE_CODE (decl) == VAR_DECL
5101               && current_function_decl != NULL_TREE
5102               && ! TREE_STATIC (decl))
5103             {
5104               error_with_decl (decl,
5105                                "section attribute cannot be specified for local variables");
5106               *no_add_attrs = true;
5107             }
5108
5109           /* The decl may have already been given a section attribute
5110              from a previous declaration.  Ensure they match.  */
5111           else if (DECL_SECTION_NAME (decl) != NULL_TREE
5112                    && strcmp (TREE_STRING_POINTER (DECL_SECTION_NAME (decl)),
5113                               TREE_STRING_POINTER (TREE_VALUE (args))) != 0)
5114             {
5115               error_with_decl (*node,
5116                                "section of `%s' conflicts with previous declaration");
5117               *no_add_attrs = true;
5118             }
5119           else
5120             DECL_SECTION_NAME (decl) = TREE_VALUE (args);
5121         }
5122       else
5123         {
5124           error_with_decl (*node,
5125                            "section attribute not allowed for `%s'");
5126           *no_add_attrs = true;
5127         }
5128     }
5129   else
5130     {
5131       error_with_decl (*node,
5132                        "section attributes are not supported for this target");
5133       *no_add_attrs = true;
5134     }
5135
5136   return NULL_TREE;
5137 }
5138
5139 /* Handle a "aligned" attribute; arguments as in
5140    struct attribute_spec.handler.  */
5141
5142 static tree
5143 handle_aligned_attribute (node, name, args, flags, no_add_attrs)
5144      tree *node;
5145      tree name ATTRIBUTE_UNUSED;
5146      tree args;
5147      int flags;
5148      bool *no_add_attrs;
5149 {
5150   tree decl = NULL_TREE;
5151   tree *type = NULL;
5152   int is_type = 0;
5153   tree align_expr = (args ? TREE_VALUE (args)
5154                      : size_int (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
5155   int i;
5156
5157   if (DECL_P (*node))
5158     {
5159       decl = *node;
5160       type = &TREE_TYPE (decl);
5161       is_type = TREE_CODE (*node) == TYPE_DECL;
5162     }
5163   else if (TYPE_P (*node))
5164     type = node, is_type = 1;
5165
5166   /* Strip any NOPs of any kind.  */
5167   while (TREE_CODE (align_expr) == NOP_EXPR
5168          || TREE_CODE (align_expr) == CONVERT_EXPR
5169          || TREE_CODE (align_expr) == NON_LVALUE_EXPR)
5170     align_expr = TREE_OPERAND (align_expr, 0);
5171
5172   if (TREE_CODE (align_expr) != INTEGER_CST)
5173     {
5174       error ("requested alignment is not a constant");
5175       *no_add_attrs = true;
5176     }
5177   else if ((i = tree_log2 (align_expr)) == -1)
5178     {
5179       error ("requested alignment is not a power of 2");
5180       *no_add_attrs = true;
5181     }
5182   else if (i > HOST_BITS_PER_INT - 2)
5183     {
5184       error ("requested alignment is too large");
5185       *no_add_attrs = true;
5186     }
5187   else if (is_type)
5188     {
5189       /* If we have a TYPE_DECL, then copy the type, so that we
5190          don't accidentally modify a builtin type.  See pushdecl.  */
5191       if (decl && TREE_TYPE (decl) != error_mark_node
5192           && DECL_ORIGINAL_TYPE (decl) == NULL_TREE)
5193         {
5194           tree tt = TREE_TYPE (decl);
5195           *type = build_type_copy (*type);
5196           DECL_ORIGINAL_TYPE (decl) = tt;
5197           TYPE_NAME (*type) = decl;
5198           TREE_USED (*type) = TREE_USED (decl);
5199           TREE_TYPE (decl) = *type;
5200         }
5201       else if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
5202         *type = build_type_copy (*type);
5203
5204       TYPE_ALIGN (*type) = (1 << i) * BITS_PER_UNIT;
5205       TYPE_USER_ALIGN (*type) = 1;
5206     }
5207   else if (TREE_CODE (decl) != VAR_DECL
5208            && TREE_CODE (decl) != FIELD_DECL)
5209     {
5210       error_with_decl (decl,
5211                        "alignment may not be specified for `%s'");
5212       *no_add_attrs = true;
5213     }
5214   else
5215     {
5216       DECL_ALIGN (decl) = (1 << i) * BITS_PER_UNIT;
5217       DECL_USER_ALIGN (decl) = 1;
5218     }
5219
5220   return NULL_TREE;
5221 }
5222
5223 /* Handle a "weak" attribute; arguments as in
5224    struct attribute_spec.handler.  */
5225
5226 static tree
5227 handle_weak_attribute (node, name, args, flags, no_add_attrs)
5228      tree *node;
5229      tree name ATTRIBUTE_UNUSED;
5230      tree args ATTRIBUTE_UNUSED;
5231      int flags ATTRIBUTE_UNUSED;
5232      bool *no_add_attrs ATTRIBUTE_UNUSED;
5233 {
5234   declare_weak (*node);
5235
5236   return NULL_TREE;
5237 }
5238
5239 /* Handle an "alias" attribute; arguments as in
5240    struct attribute_spec.handler.  */
5241
5242 static tree
5243 handle_alias_attribute (node, name, args, flags, no_add_attrs)
5244      tree *node;
5245      tree name;
5246      tree args;
5247      int flags ATTRIBUTE_UNUSED;
5248      bool *no_add_attrs;
5249 {
5250   tree decl = *node;
5251
5252   if ((TREE_CODE (decl) == FUNCTION_DECL && DECL_INITIAL (decl))
5253       || (TREE_CODE (decl) != FUNCTION_DECL && ! DECL_EXTERNAL (decl)))
5254     {
5255       error_with_decl (decl,
5256                        "`%s' defined both normally and as an alias");
5257       *no_add_attrs = true;
5258     }
5259   else if (decl_function_context (decl) == 0)
5260     {
5261       tree id;
5262
5263       id = TREE_VALUE (args);
5264       if (TREE_CODE (id) != STRING_CST)
5265         {
5266           error ("alias arg not a string");
5267           *no_add_attrs = true;
5268           return NULL_TREE;
5269         }
5270       id = get_identifier (TREE_STRING_POINTER (id));
5271       /* This counts as a use of the object pointed to.  */
5272       TREE_USED (id) = 1;
5273
5274       if (TREE_CODE (decl) == FUNCTION_DECL)
5275         DECL_INITIAL (decl) = error_mark_node;
5276       else
5277         DECL_EXTERNAL (decl) = 0;
5278     }
5279   else
5280     {
5281       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
5282       *no_add_attrs = true;
5283     }
5284
5285   return NULL_TREE;
5286 }
5287
5288 /* Handle an "visibility" attribute; arguments as in
5289    struct attribute_spec.handler.  */
5290
5291 static tree
5292 handle_visibility_attribute (node, name, args, flags, no_add_attrs)
5293      tree *node;
5294      tree name;
5295      tree args;
5296      int flags ATTRIBUTE_UNUSED;
5297      bool *no_add_attrs;
5298 {
5299   tree decl = *node;
5300
5301   if (decl_function_context (decl) != 0 || ! TREE_PUBLIC (decl))
5302     {
5303       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
5304       *no_add_attrs = true;
5305     }
5306   else
5307     {
5308       tree id;
5309
5310       id = TREE_VALUE (args);
5311       if (TREE_CODE (id) != STRING_CST)
5312         {
5313           error ("visibility arg not a string");
5314           *no_add_attrs = true;
5315           return NULL_TREE;
5316         }
5317       if (strcmp (TREE_STRING_POINTER (id), "hidden")
5318           && strcmp (TREE_STRING_POINTER (id), "protected")
5319           && strcmp (TREE_STRING_POINTER (id), "internal"))
5320         {
5321           error ("visibility arg must be one of \"hidden\", \"protected\" or \"internal\"");
5322           *no_add_attrs = true;
5323           return NULL_TREE;
5324         }
5325     }
5326
5327   return NULL_TREE;
5328 }
5329
5330 /* Handle a "no_instrument_function" attribute; arguments as in
5331    struct attribute_spec.handler.  */
5332
5333 static tree
5334 handle_no_instrument_function_attribute (node, name, args, flags, no_add_attrs)
5335      tree *node;
5336      tree name;
5337      tree args ATTRIBUTE_UNUSED;
5338      int flags ATTRIBUTE_UNUSED;
5339      bool *no_add_attrs;
5340 {
5341   tree decl = *node;
5342
5343   if (TREE_CODE (decl) != FUNCTION_DECL)
5344     {
5345       error_with_decl (decl,
5346                        "`%s' attribute applies only to functions",
5347                        IDENTIFIER_POINTER (name));
5348       *no_add_attrs = true;
5349     }
5350   else if (DECL_INITIAL (decl))
5351     {
5352       error_with_decl (decl,
5353                        "can't set `%s' attribute after definition",
5354                        IDENTIFIER_POINTER (name));
5355       *no_add_attrs = true;
5356     }
5357   else
5358     DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl) = 1;
5359
5360   return NULL_TREE;
5361 }
5362
5363 /* Handle a "malloc" attribute; arguments as in
5364    struct attribute_spec.handler.  */
5365
5366 static tree
5367 handle_malloc_attribute (node, name, args, flags, no_add_attrs)
5368      tree *node;
5369      tree name;
5370      tree args ATTRIBUTE_UNUSED;
5371      int flags ATTRIBUTE_UNUSED;
5372      bool *no_add_attrs;
5373 {
5374   if (TREE_CODE (*node) == FUNCTION_DECL)
5375     DECL_IS_MALLOC (*node) = 1;
5376   /* ??? TODO: Support types.  */
5377   else
5378     {
5379       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
5380       *no_add_attrs = true;
5381     }
5382
5383   return NULL_TREE;
5384 }
5385
5386 /* Handle a "no_limit_stack" attribute; arguments as in
5387    struct attribute_spec.handler.  */
5388
5389 static tree
5390 handle_no_limit_stack_attribute (node, name, args, flags, no_add_attrs)
5391      tree *node;
5392      tree name;
5393      tree args ATTRIBUTE_UNUSED;
5394      int flags ATTRIBUTE_UNUSED;
5395      bool *no_add_attrs;
5396 {
5397   tree decl = *node;
5398
5399   if (TREE_CODE (decl) != FUNCTION_DECL)
5400     {
5401       error_with_decl (decl,
5402                        "`%s' attribute applies only to functions",
5403                        IDENTIFIER_POINTER (name));
5404       *no_add_attrs = true;
5405     }
5406   else if (DECL_INITIAL (decl))
5407     {
5408       error_with_decl (decl,
5409                        "can't set `%s' attribute after definition",
5410                        IDENTIFIER_POINTER (name));
5411       *no_add_attrs = true;
5412     }
5413   else
5414     DECL_NO_LIMIT_STACK (decl) = 1;
5415
5416   return NULL_TREE;
5417 }
5418
5419 /* Handle a "pure" attribute; arguments as in
5420    struct attribute_spec.handler.  */
5421
5422 static tree
5423 handle_pure_attribute (node, name, args, flags, no_add_attrs)
5424      tree *node;
5425      tree name;
5426      tree args ATTRIBUTE_UNUSED;
5427      int flags ATTRIBUTE_UNUSED;
5428      bool *no_add_attrs;
5429 {
5430   if (TREE_CODE (*node) == FUNCTION_DECL)
5431     DECL_IS_PURE (*node) = 1;
5432   /* ??? TODO: Support types.  */
5433   else
5434     {
5435       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
5436       *no_add_attrs = true;
5437     }
5438
5439   return NULL_TREE;
5440 }
5441
5442 /* Handle a "deprecated" attribute; arguments as in
5443    struct attribute_spec.handler.  */
5444
5445 static tree
5446 handle_deprecated_attribute (node, name, args, flags, no_add_attrs)
5447      tree *node;
5448      tree name;
5449      tree args ATTRIBUTE_UNUSED;
5450      int flags;
5451      bool *no_add_attrs;
5452 {
5453   tree type = NULL_TREE;
5454   int warn = 0;
5455   const char *what = NULL;
5456
5457   if (DECL_P (*node))
5458     {
5459       tree decl = *node;
5460       type = TREE_TYPE (decl);
5461
5462       if (TREE_CODE (decl) == TYPE_DECL
5463           || TREE_CODE (decl) == PARM_DECL
5464           || TREE_CODE (decl) == VAR_DECL
5465           || TREE_CODE (decl) == FUNCTION_DECL
5466           || TREE_CODE (decl) == FIELD_DECL)
5467         TREE_DEPRECATED (decl) = 1;
5468       else
5469         warn = 1;
5470     }
5471   else if (TYPE_P (*node))
5472     {
5473       if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
5474         *node = build_type_copy (*node);
5475       TREE_DEPRECATED (*node) = 1;
5476       type = *node;
5477     }
5478   else
5479     warn = 1;
5480
5481   if (warn)
5482     {
5483       *no_add_attrs = true;
5484       if (type && TYPE_NAME (type))
5485         {
5486           if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
5487             what = IDENTIFIER_POINTER (TYPE_NAME (*node));
5488           else if (TREE_CODE (TYPE_NAME (type)) == TYPE_DECL
5489                    && DECL_NAME (TYPE_NAME (type)))
5490             what = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)));
5491         }
5492       if (what)
5493         warning ("`%s' attribute ignored for `%s'",
5494                   IDENTIFIER_POINTER (name), what);
5495       else
5496         warning ("`%s' attribute ignored",
5497                       IDENTIFIER_POINTER (name));
5498     }
5499
5500   return NULL_TREE;
5501 }
5502
5503 /* Keep a list of vector type nodes we created in handle_vector_size_attribute,
5504    to prevent us from duplicating type nodes unnecessarily.
5505    The normal mechanism to prevent duplicates is to use type_hash_canon, but
5506    since we want to distinguish types that are essentially identical (except
5507    for their debug representation), we use a local list here.  */
5508 static tree vector_type_node_list = 0;
5509
5510 /* Handle a "vector_size" attribute; arguments as in
5511    struct attribute_spec.handler.  */
5512
5513 static tree
5514 handle_vector_size_attribute (node, name, args, flags, no_add_attrs)
5515      tree *node;
5516      tree name;
5517      tree args;
5518      int flags ATTRIBUTE_UNUSED;
5519      bool *no_add_attrs;
5520 {
5521   unsigned HOST_WIDE_INT vecsize, nunits;
5522   enum machine_mode mode, orig_mode, new_mode;
5523   tree type = *node, new_type = NULL_TREE;
5524   tree type_list_node;
5525
5526   *no_add_attrs = true;
5527
5528   if (! host_integerp (TREE_VALUE (args), 1))
5529     {
5530       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
5531       return NULL_TREE;
5532     }
5533
5534   /* Get the vector size (in bytes).  */
5535   vecsize = tree_low_cst (TREE_VALUE (args), 1);
5536
5537   /* We need to provide for vector pointers, vector arrays, and
5538      functions returning vectors.  For example:
5539
5540        __attribute__((vector_size(16))) short *foo;
5541
5542      In this case, the mode is SI, but the type being modified is
5543      HI, so we need to look further.  */
5544
5545   while (POINTER_TYPE_P (type)
5546          || TREE_CODE (type) == FUNCTION_TYPE
5547          || TREE_CODE (type) == ARRAY_TYPE)
5548     type = TREE_TYPE (type);
5549
5550   /* Get the mode of the type being modified.  */
5551   orig_mode = TYPE_MODE (type);
5552
5553   if (TREE_CODE (type) == RECORD_TYPE
5554       || (GET_MODE_CLASS (orig_mode) != MODE_FLOAT
5555           && GET_MODE_CLASS (orig_mode) != MODE_INT)
5556       || ! host_integerp (TYPE_SIZE_UNIT (type), 1))
5557     {
5558       error ("invalid vector type for attribute `%s'",
5559              IDENTIFIER_POINTER (name));
5560       return NULL_TREE;
5561     }
5562
5563   /* Calculate how many units fit in the vector.  */
5564   nunits = vecsize / tree_low_cst (TYPE_SIZE_UNIT (type), 1);
5565
5566   /* Find a suitably sized vector.  */
5567   new_mode = VOIDmode;
5568   for (mode = GET_CLASS_NARROWEST_MODE (GET_MODE_CLASS (orig_mode) == MODE_INT
5569                                         ? MODE_VECTOR_INT
5570                                         : MODE_VECTOR_FLOAT);
5571        mode != VOIDmode;
5572        mode = GET_MODE_WIDER_MODE (mode))
5573     if (vecsize == GET_MODE_SIZE (mode)
5574         && nunits == (unsigned HOST_WIDE_INT) GET_MODE_NUNITS (mode))
5575       {
5576         new_mode = mode;
5577         break;
5578       }
5579
5580     if (new_mode == VOIDmode)
5581     {
5582       error ("no vector mode with the size and type specified could be found");
5583       return NULL_TREE;
5584     }
5585
5586   for (type_list_node = vector_type_node_list; type_list_node;
5587        type_list_node = TREE_CHAIN (type_list_node))
5588     {
5589       tree other_type = TREE_VALUE (type_list_node);
5590       tree record = TYPE_DEBUG_REPRESENTATION_TYPE (other_type);
5591       tree fields = TYPE_FIELDS (record);
5592       tree field_type = TREE_TYPE (fields);
5593       tree array_type = TREE_TYPE (field_type);
5594       if (TREE_CODE (fields) != FIELD_DECL
5595           || TREE_CODE (field_type) != ARRAY_TYPE)
5596         abort ();
5597
5598       if (TYPE_MODE (other_type) == mode && type == array_type)
5599         {
5600           new_type = other_type;
5601           break;
5602         }
5603     }
5604
5605   if (new_type == NULL_TREE)
5606     {
5607       tree index, array, rt, list_node;
5608
5609       new_type = (*lang_hooks.types.type_for_mode) (new_mode,
5610                                                     TREE_UNSIGNED (type));
5611
5612       if (!new_type)
5613         {
5614           error ("no vector mode with the size and type specified could be found");
5615           return NULL_TREE;
5616         }
5617
5618       new_type = build_type_copy (new_type);
5619
5620       /* If this is a vector, make sure we either have hardware
5621          support, or we can emulate it.  */
5622       if ((GET_MODE_CLASS (mode) == MODE_VECTOR_INT
5623            || GET_MODE_CLASS (mode) == MODE_VECTOR_FLOAT)
5624           && !vector_mode_valid_p (mode))
5625         {
5626           error ("unable to emulate '%s'", GET_MODE_NAME (mode));
5627           return NULL_TREE;
5628         }
5629
5630       /* Set the debug information here, because this is the only
5631          place where we know the underlying type for a vector made
5632          with vector_size.  For debugging purposes we pretend a vector
5633          is an array within a structure.  */
5634       index = build_int_2 (TYPE_VECTOR_SUBPARTS (new_type) - 1, 0);
5635       array = build_array_type (type, build_index_type (index));
5636       rt = make_node (RECORD_TYPE);
5637
5638       TYPE_FIELDS (rt) = build_decl (FIELD_DECL, get_identifier ("f"), array);
5639       DECL_CONTEXT (TYPE_FIELDS (rt)) = rt;
5640       layout_type (rt);
5641       TYPE_DEBUG_REPRESENTATION_TYPE (new_type) = rt;
5642
5643       list_node = build_tree_list (NULL, new_type);
5644       TREE_CHAIN (list_node) = vector_type_node_list;
5645       vector_type_node_list = list_node;
5646     }
5647
5648   /* Build back pointers if needed.  */
5649   *node = vector_size_helper (*node, new_type);
5650
5651   return NULL_TREE;
5652 }
5653
5654 /* HACK.  GROSS.  This is absolutely disgusting.  I wish there was a
5655    better way.
5656
5657    If we requested a pointer to a vector, build up the pointers that
5658    we stripped off while looking for the inner type.  Similarly for
5659    return values from functions.
5660
5661    The argument "type" is the top of the chain, and "bottom" is the
5662    new type which we will point to.  */
5663
5664 static tree
5665 vector_size_helper (type, bottom)
5666      tree type, bottom;
5667 {
5668   tree inner, outer;
5669
5670   if (POINTER_TYPE_P (type))
5671     {
5672       inner = vector_size_helper (TREE_TYPE (type), bottom);
5673       outer = build_pointer_type (inner);
5674     }
5675   else if (TREE_CODE (type) == ARRAY_TYPE)
5676     {
5677       inner = vector_size_helper (TREE_TYPE (type), bottom);
5678       outer = build_array_type (inner, TYPE_VALUES (type));
5679     }
5680   else if (TREE_CODE (type) == FUNCTION_TYPE)
5681     {
5682       inner = vector_size_helper (TREE_TYPE (type), bottom);
5683       outer = build_function_type (inner, TYPE_VALUES (type));
5684     }
5685   else
5686     return bottom;
5687
5688   TREE_READONLY (outer) = TREE_READONLY (type);
5689   TREE_THIS_VOLATILE (outer) = TREE_THIS_VOLATILE (type);
5690
5691   return outer;
5692 }
5693
5694 /* Handle the "nonnull" attribute.  */
5695 static tree
5696 handle_nonnull_attribute (node, name, args, flags, no_add_attrs)
5697      tree *node;
5698      tree name ATTRIBUTE_UNUSED;
5699      tree args;
5700      int flags ATTRIBUTE_UNUSED;
5701      bool *no_add_attrs;
5702 {
5703   tree type = *node;
5704   unsigned HOST_WIDE_INT attr_arg_num;
5705
5706   /* If no arguments are specified, all pointer arguments should be
5707      non-null.  Veryify a full prototype is given so that the arguments
5708      will have the correct types when we actually check them later.  */
5709   if (! args)
5710     {
5711       if (! TYPE_ARG_TYPES (type))
5712         {
5713           error ("nonnull attribute without arguments on a non-prototype");
5714           *no_add_attrs = true;
5715         }
5716       return NULL_TREE;
5717     }
5718
5719   /* Argument list specified.  Verify that each argument number references
5720      a pointer argument.  */
5721   for (attr_arg_num = 1; args; args = TREE_CHAIN (args))
5722     {
5723       tree argument;
5724       unsigned HOST_WIDE_INT arg_num, ck_num;
5725
5726       if (! get_nonnull_operand (TREE_VALUE (args), &arg_num))
5727         {
5728           error ("nonnull argument has invalid operand number (arg %lu)",
5729                  (unsigned long) attr_arg_num);
5730           *no_add_attrs = true;
5731           return NULL_TREE;
5732         }
5733
5734       argument = TYPE_ARG_TYPES (type);
5735       if (argument)
5736         {
5737           for (ck_num = 1; ; ck_num++)
5738             {
5739               if (! argument || ck_num == arg_num)
5740                 break;
5741               argument = TREE_CHAIN (argument);
5742             }
5743
5744           if (! argument
5745               || TREE_CODE (TREE_VALUE (argument)) == VOID_TYPE)
5746             {
5747               error ("nonnull argument with out-of-range operand number (arg %lu, operand %lu)",
5748                      (unsigned long) attr_arg_num, (unsigned long) arg_num);
5749               *no_add_attrs = true;
5750               return NULL_TREE;
5751             }
5752
5753           if (TREE_CODE (TREE_VALUE (argument)) != POINTER_TYPE)
5754             {
5755               error ("nonnull argument references non-pointer operand (arg %lu, operand %lu)",
5756                    (unsigned long) attr_arg_num, (unsigned long) arg_num);
5757               *no_add_attrs = true;
5758               return NULL_TREE;
5759             }
5760         }
5761     }
5762
5763   return NULL_TREE;
5764 }
5765
5766 /* Check the argument list of a function call for null in argument slots
5767    that are marked as requiring a non-null pointer argument.  */
5768
5769 static void
5770 check_function_nonnull (attrs, params)
5771      tree attrs;
5772      tree params;
5773 {
5774   tree a, args, param;
5775   int param_num;
5776
5777   for (a = attrs; a; a = TREE_CHAIN (a))
5778     {
5779       if (is_attribute_p ("nonnull", TREE_PURPOSE (a)))
5780         {
5781           args = TREE_VALUE (a);
5782
5783           /* Walk the argument list.  If we encounter an argument number we
5784              should check for non-null, do it.  If the attribute has no args,
5785              then every pointer argument is checked (in which case the check
5786              for pointer type is done in check_nonnull_arg).  */
5787           for (param = params, param_num = 1; ;
5788                param_num++, param = TREE_CHAIN (param))
5789             {
5790               if (! param)
5791                 break;
5792               if (! args || nonnull_check_p (args, param_num))
5793                 check_function_arguments_recurse (check_nonnull_arg, NULL,
5794                                                   TREE_VALUE (param),
5795                                                   param_num);
5796             }
5797         }
5798     }
5799 }
5800
5801 /* Helper for check_function_nonnull; given a list of operands which
5802    must be non-null in ARGS, determine if operand PARAM_NUM should be
5803    checked.  */
5804
5805 static bool
5806 nonnull_check_p (args, param_num)
5807      tree args;
5808      unsigned HOST_WIDE_INT param_num;
5809 {
5810   unsigned HOST_WIDE_INT arg_num;
5811
5812   for (; args; args = TREE_CHAIN (args))
5813     {
5814       if (! get_nonnull_operand (TREE_VALUE (args), &arg_num))
5815         abort ();
5816
5817       if (arg_num == param_num)
5818         return true;
5819     }
5820   return false;
5821 }
5822
5823 /* Check that the function argument PARAM (which is operand number
5824    PARAM_NUM) is non-null.  This is called by check_function_nonnull
5825    via check_function_arguments_recurse.  */
5826
5827 static void
5828 check_nonnull_arg (ctx, param, param_num)
5829      void *ctx ATTRIBUTE_UNUSED;
5830      tree param;
5831      unsigned HOST_WIDE_INT param_num;
5832 {
5833   /* Just skip checking the argument if it's not a pointer.  This can
5834      happen if the "nonnull" attribute was given without an operand
5835      list (which means to check every pointer argument).  */
5836
5837   if (TREE_CODE (TREE_TYPE (param)) != POINTER_TYPE)
5838     return;
5839
5840   if (integer_zerop (param))
5841     warning ("null argument where non-null required (arg %lu)",
5842              (unsigned long) param_num);
5843 }
5844
5845 /* Helper for nonnull attribute handling; fetch the operand number
5846    from the attribute argument list.  */
5847
5848 static bool
5849 get_nonnull_operand (arg_num_expr, valp)
5850      tree arg_num_expr;
5851      unsigned HOST_WIDE_INT *valp;
5852 {
5853   /* Strip any conversions from the arg number and verify they
5854      are constants.  */
5855   while (TREE_CODE (arg_num_expr) == NOP_EXPR
5856          || TREE_CODE (arg_num_expr) == CONVERT_EXPR
5857          || TREE_CODE (arg_num_expr) == NON_LVALUE_EXPR)
5858     arg_num_expr = TREE_OPERAND (arg_num_expr, 0);
5859
5860   if (TREE_CODE (arg_num_expr) != INTEGER_CST
5861       || TREE_INT_CST_HIGH (arg_num_expr) != 0)
5862     return false;
5863
5864   *valp = TREE_INT_CST_LOW (arg_num_expr);
5865   return true;
5866 }
5867
5868 /* Handle a "nothrow" attribute; arguments as in
5869    struct attribute_spec.handler.  */
5870
5871 static tree
5872 handle_nothrow_attribute (node, name, args, flags, no_add_attrs)
5873      tree *node;
5874      tree name;
5875      tree args ATTRIBUTE_UNUSED;
5876      int flags ATTRIBUTE_UNUSED;
5877      bool *no_add_attrs;
5878 {
5879   if (TREE_CODE (*node) == FUNCTION_DECL)
5880     TREE_NOTHROW (*node) = 1;
5881   /* ??? TODO: Support types.  */
5882   else
5883     {
5884       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
5885       *no_add_attrs = true;
5886     }
5887
5888   return NULL_TREE;
5889 }
5890 \f
5891 /* Check for valid arguments being passed to a function.  */
5892 void
5893 check_function_arguments (attrs, params)
5894      tree attrs;
5895      tree params;
5896 {
5897   /* Check for null being passed in a pointer argument that must be
5898      non-null.  We also need to do this if format checking is enabled.  */
5899
5900   if (warn_nonnull)
5901     check_function_nonnull (attrs, params);
5902
5903   /* Check for errors in format strings.  */
5904
5905   if (warn_format)
5906     check_function_format (NULL, attrs, params);
5907 }
5908
5909 /* Generic argument checking recursion routine.  PARAM is the argument to
5910    be checked.  PARAM_NUM is the number of the argument.  CALLBACK is invoked
5911    once the argument is resolved.  CTX is context for the callback.  */
5912 void
5913 check_function_arguments_recurse (callback, ctx, param, param_num)
5914      void (*callback) PARAMS ((void *, tree, unsigned HOST_WIDE_INT));
5915      void *ctx;
5916      tree param;
5917      unsigned HOST_WIDE_INT param_num;
5918 {
5919   if (TREE_CODE (param) == NOP_EXPR)
5920     {
5921       /* Strip coercion.  */
5922       check_function_arguments_recurse (callback, ctx,
5923                                         TREE_OPERAND (param, 0), param_num);
5924       return;
5925     }
5926
5927   if (TREE_CODE (param) == CALL_EXPR)
5928     {
5929       tree type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (param, 0)));
5930       tree attrs;
5931       bool found_format_arg = false;
5932
5933       /* See if this is a call to a known internationalization function
5934          that modifies a format arg.  Such a function may have multiple
5935          format_arg attributes (for example, ngettext).  */
5936
5937       for (attrs = TYPE_ATTRIBUTES (type);
5938            attrs;
5939            attrs = TREE_CHAIN (attrs))
5940         if (is_attribute_p ("format_arg", TREE_PURPOSE (attrs)))
5941           {
5942             tree inner_args;
5943             tree format_num_expr;
5944             int format_num;
5945             int i;
5946
5947             /* Extract the argument number, which was previously checked
5948                to be valid.  */
5949             format_num_expr = TREE_VALUE (TREE_VALUE (attrs));
5950             while (TREE_CODE (format_num_expr) == NOP_EXPR
5951                    || TREE_CODE (format_num_expr) == CONVERT_EXPR
5952                    || TREE_CODE (format_num_expr) == NON_LVALUE_EXPR)
5953               format_num_expr = TREE_OPERAND (format_num_expr, 0);
5954
5955             if (TREE_CODE (format_num_expr) != INTEGER_CST
5956                 || TREE_INT_CST_HIGH (format_num_expr) != 0)
5957               abort ();
5958
5959             format_num = TREE_INT_CST_LOW (format_num_expr);
5960
5961             for (inner_args = TREE_OPERAND (param, 1), i = 1;
5962                  inner_args != 0;
5963                  inner_args = TREE_CHAIN (inner_args), i++)
5964               if (i == format_num)
5965                 {
5966                   check_function_arguments_recurse (callback, ctx,
5967                                                     TREE_VALUE (inner_args),
5968                                                     param_num);
5969                   found_format_arg = true;
5970                   break;
5971                 }
5972           }
5973
5974       /* If we found a format_arg attribute and did a recursive check,
5975          we are done with checking this argument.  Otherwise, we continue
5976          and this will be considered a non-literal.  */
5977       if (found_format_arg)
5978         return;
5979     }
5980
5981   if (TREE_CODE (param) == COND_EXPR)
5982     {
5983       /* Check both halves of the conditional expression.  */
5984       check_function_arguments_recurse (callback, ctx,
5985                                         TREE_OPERAND (param, 1), param_num);
5986       check_function_arguments_recurse (callback, ctx,
5987                                         TREE_OPERAND (param, 2), param_num);
5988       return;
5989     }
5990
5991   (*callback) (ctx, param, param_num);
5992 }
5993
5994 #include "gt-c-common.h"