gcc/targhooks.c

   1 /* Default target hook functions.
   2    Copyright (C) 2003-2019 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 /* The migration of target macros to target hooks works as follows:
  21
  22    1. Create a target hook that uses the existing target macros to
  23       implement the same functionality.
  24
  25    2. Convert all the MI files to use the hook instead of the macro.
  26
  27    3. Repeat for a majority of the remaining target macros.  This will
  28       take some time.
  29
  30    4. Tell target maintainers to start migrating.
  31
  32    5. Eventually convert the backends to override the hook instead of
  33       defining the macros.  This will take some time too.
  34
  35    6. TBD when, poison the macros.  Unmigrated targets will break at
  36       this point.
  37
  38    Note that we expect steps 1-3 to be done by the people that
  39    understand what the MI does with each macro, and step 5 to be done
  40    by the target maintainers for their respective targets.
  41
  42    Note that steps 1 and 2 don't have to be done together, but no
  43    target can override the new hook until step 2 is complete for it.
  44
  45    Once the macros are poisoned, we will revert to the old migration
  46    rules - migrate the macro, callers, and targets all at once.  This
  47    comment can thus be removed at that point.  */
  48
  49 #include "config.h"
  50 #include "system.h"
  51 #include "coretypes.h"
  52 #include "target.h"
  53 #include "function.h"
  54 #include "rtl.h"
  55 #include "tree.h"
  56 #include "tree-ssa-alias.h"
  57 #include "gimple-expr.h"
  58 #include "memmodel.h"
  59 #include "tm_p.h"
  60 #include "stringpool.h"
  61 #include "tree-vrp.h"
  62 #include "tree-ssanames.h"
  63 #include "profile-count.h"
  64 #include "optabs.h"
  65 #include "regs.h"
  66 #include "recog.h"
  67 #include "diagnostic-core.h"
  68 #include "fold-const.h"
  69 #include "stor-layout.h"
  70 #include "varasm.h"
  71 #include "flags.h"
  72 #include "explow.h"
  73 #include "calls.h"
  74 #include "expr.h"
  75 #include "output.h"
  76 #include "common/common-target.h"
  77 #include "reload.h"
  78 #include "intl.h"
  79 #include "opts.h"
  80 #include "gimplify.h"
  81 #include "predict.h"
  82 #include "params.h"
  83 #include "real.h"
  84 #include "langhooks.h"
  85 #include "sbitmap.h"
  86
  87 bool
  88 default_legitimate_address_p (machine_mode mode ATTRIBUTE_UNUSED,
  89                               rtx addr ATTRIBUTE_UNUSED,
  90                               bool strict ATTRIBUTE_UNUSED)
  91 {
  92 #ifdef GO_IF_LEGITIMATE_ADDRESS
  93   /* Defer to the old implementation using a goto.  */
  94   if (strict)
  95     return strict_memory_address_p (mode, addr);
  96   else
  97     return memory_address_p (mode, addr);
  98 #else
  99   gcc_unreachable ();
 100 #endif
 101 }
 102
 103 void
 104 default_external_libcall (rtx fun ATTRIBUTE_UNUSED)
 105 {
 106 #ifdef ASM_OUTPUT_EXTERNAL_LIBCALL
 107   ASM_OUTPUT_EXTERNAL_LIBCALL (asm_out_file, fun);
 108 #endif
 109 }
 110
 111 int
 112 default_unspec_may_trap_p (const_rtx x, unsigned flags)
 113 {
 114   int i;
 115
 116   /* Any floating arithmetic may trap.  */
 117   if ((SCALAR_FLOAT_MODE_P (GET_MODE (x)) && flag_trapping_math))
 118     return 1;
 119
 120   for (i = 0; i < XVECLEN (x, 0); ++i)
 121     {
 122       if (may_trap_p_1 (XVECEXP (x, 0, i), flags))
 123         return 1;
 124     }
 125
 126   return 0;
 127 }
 128
 129 machine_mode
 130 default_promote_function_mode (const_tree type ATTRIBUTE_UNUSED,
 131                                machine_mode mode,
 132                                int *punsignedp ATTRIBUTE_UNUSED,
 133                                const_tree funtype ATTRIBUTE_UNUSED,
 134                                int for_return ATTRIBUTE_UNUSED)
 135 {
 136   if (type != NULL_TREE && for_return == 2)
 137     return promote_mode (type, mode, punsignedp);
 138   return mode;
 139 }
 140
 141 machine_mode
 142 default_promote_function_mode_always_promote (const_tree type,
 143                                               machine_mode mode,
 144                                               int *punsignedp,
 145                                               const_tree funtype ATTRIBUTE_UNUSED,
 146                                               int for_return ATTRIBUTE_UNUSED)
 147 {
 148   return promote_mode (type, mode, punsignedp);
 149 }
 150
 151 machine_mode
 152 default_cc_modes_compatible (machine_mode m1, machine_mode m2)
 153 {
 154   if (m1 == m2)
 155     return m1;
 156   return VOIDmode;
 157 }
 158
 159 bool
 160 default_return_in_memory (const_tree type,
 161                           const_tree fntype ATTRIBUTE_UNUSED)
 162 {
 163   return (TYPE_MODE (type) == BLKmode);
 164 }
 165
 166 rtx
 167 default_legitimize_address (rtx x, rtx orig_x ATTRIBUTE_UNUSED,
 168                             machine_mode mode ATTRIBUTE_UNUSED)
 169 {
 170   return x;
 171 }
 172
 173 bool
 174 default_legitimize_address_displacement (rtx *, rtx *, poly_int64,
 175                                          machine_mode)
 176 {
 177   return false;
 178 }
 179
 180 bool
 181 default_const_not_ok_for_debug_p (rtx x)
 182 {
 183   if (GET_CODE (x) == UNSPEC)
 184     return true;
 185   return false;
 186 }
 187
 188 rtx
 189 default_expand_builtin_saveregs (void)
 190 {
 191   error ("%<__builtin_saveregs%> not supported by this target");
 192   return const0_rtx;
 193 }
 194
 195 void
 196 default_setup_incoming_varargs (cumulative_args_t ca ATTRIBUTE_UNUSED,
 197                                 machine_mode mode ATTRIBUTE_UNUSED,
 198                                 tree type ATTRIBUTE_UNUSED,
 199                                 int *pretend_arg_size ATTRIBUTE_UNUSED,
 200                                 int second_time ATTRIBUTE_UNUSED)
 201 {
 202 }
 203
 204 /* The default implementation of TARGET_BUILTIN_SETJMP_FRAME_VALUE.  */
 205
 206 rtx
 207 default_builtin_setjmp_frame_value (void)
 208 {
 209   return virtual_stack_vars_rtx;
 210 }
 211
 212 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns false.  */
 213
 214 bool
 215 hook_bool_CUMULATIVE_ARGS_false (cumulative_args_t ca ATTRIBUTE_UNUSED)
 216 {
 217   return false;
 218 }
 219
 220 bool
 221 default_pretend_outgoing_varargs_named (cumulative_args_t ca ATTRIBUTE_UNUSED)
 222 {
 223   return (targetm.calls.setup_incoming_varargs
 224           != default_setup_incoming_varargs);
 225 }
 226
 227 scalar_int_mode
 228 default_eh_return_filter_mode (void)
 229 {
 230   return targetm.unwind_word_mode ();
 231 }
 232
 233 scalar_int_mode
 234 default_libgcc_cmp_return_mode (void)
 235 {
 236   return word_mode;
 237 }
 238
 239 scalar_int_mode
 240 default_libgcc_shift_count_mode (void)
 241 {
 242   return word_mode;
 243 }
 244
 245 scalar_int_mode
 246 default_unwind_word_mode (void)
 247 {
 248   return word_mode;
 249 }
 250
 251 /* The default implementation of TARGET_SHIFT_TRUNCATION_MASK.  */
 252
 253 unsigned HOST_WIDE_INT
 254 default_shift_truncation_mask (machine_mode mode)
 255 {
 256   return SHIFT_COUNT_TRUNCATED ? GET_MODE_UNIT_BITSIZE (mode) - 1 : 0;
 257 }
 258
 259 /* The default implementation of TARGET_MIN_DIVISIONS_FOR_RECIP_MUL.  */
 260
 261 unsigned int
 262 default_min_divisions_for_recip_mul (machine_mode mode ATTRIBUTE_UNUSED)
 263 {
 264   return have_insn_for (DIV, mode) ? 3 : 2;
 265 }
 266
 267 /* The default implementation of TARGET_MODE_REP_EXTENDED.  */
 268
 269 int
 270 default_mode_rep_extended (scalar_int_mode, scalar_int_mode)
 271 {
 272   return UNKNOWN;
 273 }
 274
 275 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns true.  */
 276
 277 bool
 278 hook_bool_CUMULATIVE_ARGS_true (cumulative_args_t a ATTRIBUTE_UNUSED)
 279 {
 280   return true;
 281 }
 282
 283 /* Return machine mode for non-standard suffix
 284    or VOIDmode if non-standard suffixes are unsupported.  */
 285 machine_mode
 286 default_mode_for_suffix (char suffix ATTRIBUTE_UNUSED)
 287 {
 288   return VOIDmode;
 289 }
 290
 291 /* The generic C++ ABI specifies this is a 64-bit value.  */
 292 tree
 293 default_cxx_guard_type (void)
 294 {
 295   return long_long_integer_type_node;
 296 }
 297
 298 /* Returns the size of the cookie to use when allocating an array
 299    whose elements have the indicated TYPE.  Assumes that it is already
 300    known that a cookie is needed.  */
 301
 302 tree
 303 default_cxx_get_cookie_size (tree type)
 304 {
 305   tree cookie_size;
 306
 307   /* We need to allocate an additional max (sizeof (size_t), alignof
 308      (true_type)) bytes.  */
 309   tree sizetype_size;
 310   tree type_align;
 311
 312   sizetype_size = size_in_bytes (sizetype);
 313   type_align = size_int (TYPE_ALIGN_UNIT (type));
 314   if (tree_int_cst_lt (type_align, sizetype_size))
 315     cookie_size = sizetype_size;
 316   else
 317     cookie_size = type_align;
 318
 319   return cookie_size;
 320 }
 321
 322 /* Return true if a parameter must be passed by reference.  This version
 323    of the TARGET_PASS_BY_REFERENCE hook uses just MUST_PASS_IN_STACK.  */
 324
 325 bool
 326 hook_pass_by_reference_must_pass_in_stack (cumulative_args_t c ATTRIBUTE_UNUSED,
 327         machine_mode mode ATTRIBUTE_UNUSED, const_tree type ATTRIBUTE_UNUSED,
 328         bool named_arg ATTRIBUTE_UNUSED)
 329 {
 330   return targetm.calls.must_pass_in_stack (mode, type);
 331 }
 332
 333 /* Return true if a parameter follows callee copies conventions.  This
 334    version of the hook is true for all named arguments.  */
 335
 336 bool
 337 hook_callee_copies_named (cumulative_args_t ca ATTRIBUTE_UNUSED,
 338                           machine_mode mode ATTRIBUTE_UNUSED,
 339                           const_tree type ATTRIBUTE_UNUSED, bool named)
 340 {
 341   return named;
 342 }
 343
 344 /* Emit to STREAM the assembler syntax for insn operand X.  */
 345
 346 void
 347 default_print_operand (FILE *stream ATTRIBUTE_UNUSED, rtx x ATTRIBUTE_UNUSED,
 348                        int code ATTRIBUTE_UNUSED)
 349 {
 350 #ifdef PRINT_OPERAND
 351   PRINT_OPERAND (stream, x, code);
 352 #else
 353   gcc_unreachable ();
 354 #endif
 355 }
 356
 357 /* Emit to STREAM the assembler syntax for an insn operand whose memory
 358    address is X.  */
 359
 360 void
 361 default_print_operand_address (FILE *stream ATTRIBUTE_UNUSED,
 362                                machine_mode /*mode*/,
 363                                rtx x ATTRIBUTE_UNUSED)
 364 {
 365 #ifdef PRINT_OPERAND_ADDRESS
 366   PRINT_OPERAND_ADDRESS (stream, x);
 367 #else
 368   gcc_unreachable ();
 369 #endif
 370 }
 371
 372 /* Return true if CODE is a valid punctuation character for the
 373    `print_operand' hook.  */
 374
 375 bool
 376 default_print_operand_punct_valid_p (unsigned char code ATTRIBUTE_UNUSED)
 377 {
 378 #ifdef PRINT_OPERAND_PUNCT_VALID_P
 379   return PRINT_OPERAND_PUNCT_VALID_P (code);
 380 #else
 381   return false;
 382 #endif
 383 }
 384
 385 /* The default implementation of TARGET_MANGLE_ASSEMBLER_NAME.  */
 386 tree
 387 default_mangle_assembler_name (const char *name ATTRIBUTE_UNUSED)
 388 {
 389   const char *skipped = name + (*name == '*' ? 1 : 0);
 390   const char *stripped = targetm.strip_name_encoding (skipped);
 391   if (*name != '*' && user_label_prefix[0])
 392     stripped = ACONCAT ((user_label_prefix, stripped, NULL));
 393   return get_identifier (stripped);
 394 }
 395
 396 /* The default implementation of TARGET_TRANSLATE_MODE_ATTRIBUTE.  */
 397
 398 machine_mode
 399 default_translate_mode_attribute (machine_mode mode)
 400 {
 401   return mode;
 402 }
 403
 404 /* True if MODE is valid for the target.  By "valid", we mean able to
 405    be manipulated in non-trivial ways.  In particular, this means all
 406    the arithmetic is supported.
 407
 408    By default we guess this means that any C type is supported.  If
 409    we can't map the mode back to a type that would be available in C,
 410    then reject it.  Special case, here, is the double-word arithmetic
 411    supported by optabs.c.  */
 412
 413 bool
 414 default_scalar_mode_supported_p (scalar_mode mode)
 415 {
 416   int precision = GET_MODE_PRECISION (mode);
 417
 418   switch (GET_MODE_CLASS (mode))
 419     {
 420     case MODE_PARTIAL_INT:
 421     case MODE_INT:
 422       if (precision == CHAR_TYPE_SIZE)
 423         return true;
 424       if (precision == SHORT_TYPE_SIZE)
 425         return true;
 426       if (precision == INT_TYPE_SIZE)
 427         return true;
 428       if (precision == LONG_TYPE_SIZE)
 429         return true;
 430       if (precision == LONG_LONG_TYPE_SIZE)
 431         return true;
 432       if (precision == 2 * BITS_PER_WORD)
 433         return true;
 434       return false;
 435
 436     case MODE_FLOAT:
 437       if (precision == FLOAT_TYPE_SIZE)
 438         return true;
 439       if (precision == DOUBLE_TYPE_SIZE)
 440         return true;
 441       if (precision == LONG_DOUBLE_TYPE_SIZE)
 442         return true;
 443       return false;
 444
 445     case MODE_DECIMAL_FLOAT:
 446     case MODE_FRACT:
 447     case MODE_UFRACT:
 448     case MODE_ACCUM:
 449     case MODE_UACCUM:
 450       return false;
 451
 452     default:
 453       gcc_unreachable ();
 454     }
 455 }
 456
 457 /* Return true if libgcc supports floating-point mode MODE (known to
 458    be supported as a scalar mode).  */
 459
 460 bool
 461 default_libgcc_floating_mode_supported_p (scalar_float_mode mode)
 462 {
 463   switch (mode)
 464     {
 465 #ifdef HAVE_SFmode
 466     case E_SFmode:
 467 #endif
 468 #ifdef HAVE_DFmode
 469     case E_DFmode:
 470 #endif
 471 #ifdef HAVE_XFmode
 472     case E_XFmode:
 473 #endif
 474 #ifdef HAVE_TFmode
 475     case E_TFmode:
 476 #endif
 477       return true;
 478
 479     default:
 480       return false;
 481     }
 482 }
 483
 484 /* Return the machine mode to use for the type _FloatN, if EXTENDED is
 485    false, or _FloatNx, if EXTENDED is true, or VOIDmode if not
 486    supported.  */
 487 opt_scalar_float_mode
 488 default_floatn_mode (int n, bool extended)
 489 {
 490   if (extended)
 491     {
 492       opt_scalar_float_mode cand1, cand2;
 493       scalar_float_mode mode;
 494       switch (n)
 495         {
 496         case 32:
 497 #ifdef HAVE_DFmode
 498           cand1 = DFmode;
 499 #endif
 500           break;
 501
 502         case 64:
 503 #ifdef HAVE_XFmode
 504           cand1 = XFmode;
 505 #endif
 506 #ifdef HAVE_TFmode
 507           cand2 = TFmode;
 508 #endif
 509           break;
 510
 511         case 128:
 512           break;
 513
 514         default:
 515           /* Those are the only valid _FloatNx types.  */
 516           gcc_unreachable ();
 517         }
 518       if (cand1.exists (&mode)
 519           && REAL_MODE_FORMAT (mode)->ieee_bits > n
 520           && targetm.scalar_mode_supported_p (mode)
 521           && targetm.libgcc_floating_mode_supported_p (mode))
 522         return cand1;
 523       if (cand2.exists (&mode)
 524           && REAL_MODE_FORMAT (mode)->ieee_bits > n
 525           && targetm.scalar_mode_supported_p (mode)
 526           && targetm.libgcc_floating_mode_supported_p (mode))
 527         return cand2;
 528     }
 529   else
 530     {
 531       opt_scalar_float_mode cand;
 532       scalar_float_mode mode;
 533       switch (n)
 534         {
 535         case 16:
 536           /* Always enable _Float16 if we have basic support for the mode.
 537              Targets can control the range and precision of operations on
 538              the _Float16 type using TARGET_C_EXCESS_PRECISION.  */
 539 #ifdef HAVE_HFmode
 540           cand = HFmode;
 541 #endif
 542           break;
 543
 544         case 32:
 545 #ifdef HAVE_SFmode
 546           cand = SFmode;
 547 #endif
 548           break;
 549
 550         case 64:
 551 #ifdef HAVE_DFmode
 552           cand = DFmode;
 553 #endif
 554           break;
 555
 556         case 128:
 557 #ifdef HAVE_TFmode
 558           cand = TFmode;
 559 #endif
 560           break;
 561
 562         default:
 563           break;
 564         }
 565       if (cand.exists (&mode)
 566           && REAL_MODE_FORMAT (mode)->ieee_bits == n
 567           && targetm.scalar_mode_supported_p (mode)
 568           && targetm.libgcc_floating_mode_supported_p (mode))
 569         return cand;
 570     }
 571   return opt_scalar_float_mode ();
 572 }
 573
 574 /* Define this to return true if the _Floatn and _Floatnx built-in functions
 575    should implicitly enable the built-in function without the __builtin_ prefix
 576    in addition to the normal built-in function with the __builtin_ prefix.  The
 577    default is to only enable built-in functions without the __builtin_ prefix
 578    for the GNU C langauge.  The argument FUNC is the enum builtin_in_function
 579    id of the function to be enabled.  */
 580
 581 bool
 582 default_floatn_builtin_p (int func ATTRIBUTE_UNUSED)
 583 {
 584   static bool first_time_p = true;
 585   static bool c_or_objective_c;
 586
 587   if (first_time_p)
 588     {
 589       first_time_p = false;
 590       c_or_objective_c = lang_GNU_C () || lang_GNU_OBJC ();
 591     }
 592
 593   return c_or_objective_c;
 594 }
 595
 596 /* Make some target macros useable by target-independent code.  */
 597 bool
 598 targhook_words_big_endian (void)
 599 {
 600   return !!WORDS_BIG_ENDIAN;
 601 }
 602
 603 bool
 604 targhook_float_words_big_endian (void)
 605 {
 606   return !!FLOAT_WORDS_BIG_ENDIAN;
 607 }
 608
 609 /* True if the target supports floating-point exceptions and rounding
 610    modes.  */
 611
 612 bool
 613 default_float_exceptions_rounding_supported_p (void)
 614 {
 615 #ifdef HAVE_adddf3
 616   return HAVE_adddf3;
 617 #else
 618   return false;
 619 #endif
 620 }
 621
 622 /* True if the target supports decimal floating point.  */
 623
 624 bool
 625 default_decimal_float_supported_p (void)
 626 {
 627   return ENABLE_DECIMAL_FLOAT;
 628 }
 629
 630 /* True if the target supports fixed-point arithmetic.  */
 631
 632 bool
 633 default_fixed_point_supported_p (void)
 634 {
 635   return ENABLE_FIXED_POINT;
 636 }
 637
 638 /* True if the target supports GNU indirect functions.  */
 639
 640 bool
 641 default_has_ifunc_p (void)
 642 {
 643   return HAVE_GNU_INDIRECT_FUNCTION;
 644 }
 645
 646 /* NULL if INSN insn is valid within a low-overhead loop, otherwise returns
 647    an error message.
 648
 649    This function checks whether a given INSN is valid within a low-overhead
 650    loop.  If INSN is invalid it returns the reason for that, otherwise it
 651    returns NULL. A called function may clobber any special registers required
 652    for low-overhead looping. Additionally, some targets (eg, PPC) use the count
 653    register for branch on table instructions. We reject the doloop pattern in
 654    these cases.  */
 655
 656 const char *
 657 default_invalid_within_doloop (const rtx_insn *insn)
 658 {
 659   if (CALL_P (insn))
 660     return "Function call in loop.";
 661
 662   if (tablejump_p (insn, NULL, NULL) || computed_jump_p (insn))
 663     return "Computed branch in the loop.";
 664
 665   return NULL;
 666 }
 667
 668 /* Mapping of builtin functions to vectorized variants.  */
 669
 670 tree
 671 default_builtin_vectorized_function (unsigned int, tree, tree)
 672 {
 673   return NULL_TREE;
 674 }
 675
 676 /* Mapping of target builtin functions to vectorized variants.  */
 677
 678 tree
 679 default_builtin_md_vectorized_function (tree, tree, tree)
 680 {
 681   return NULL_TREE;
 682 }
 683
 684 /* Vectorized conversion.  */
 685
 686 tree
 687 default_builtin_vectorized_conversion (unsigned int code ATTRIBUTE_UNUSED,
 688                                        tree dest_type ATTRIBUTE_UNUSED,
 689                                        tree src_type ATTRIBUTE_UNUSED)
 690 {
 691   return NULL_TREE;
 692 }
 693
 694 /* Default vectorizer cost model values.  */
 695
 696 int
 697 default_builtin_vectorization_cost (enum vect_cost_for_stmt type_of_cost,
 698                                     tree vectype,
 699                                     int misalign ATTRIBUTE_UNUSED)
 700 {
 701   switch (type_of_cost)
 702     {
 703       case scalar_stmt:
 704       case scalar_load:
 705       case scalar_store:
 706       case vector_stmt:
 707       case vector_load:
 708       case vector_store:
 709       case vec_to_scalar:
 710       case scalar_to_vec:
 711       case cond_branch_not_taken:
 712       case vec_perm:
 713       case vec_promote_demote:
 714         return 1;
 715
 716       case unaligned_load:
 717       case unaligned_store:
 718         return 2;
 719
 720       case cond_branch_taken:
 721         return 3;
 722
 723       case vec_construct:
 724         return estimated_poly_value (TYPE_VECTOR_SUBPARTS (vectype)) - 1;
 725
 726       default:
 727         gcc_unreachable ();
 728     }
 729 }
 730
 731 /* Reciprocal.  */
 732
 733 tree
 734 default_builtin_reciprocal (tree)
 735 {
 736   return NULL_TREE;
 737 }
 738
 739 bool
 740 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false (
 741         cumulative_args_t ca ATTRIBUTE_UNUSED,
 742         machine_mode mode ATTRIBUTE_UNUSED,
 743         const_tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
 744 {
 745   return false;
 746 }
 747
 748 bool
 749 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_true (
 750         cumulative_args_t ca ATTRIBUTE_UNUSED,
 751         machine_mode mode ATTRIBUTE_UNUSED,
 752         const_tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
 753 {
 754   return true;
 755 }
 756
 757 int
 758 hook_int_CUMULATIVE_ARGS_mode_tree_bool_0 (
 759         cumulative_args_t ca ATTRIBUTE_UNUSED,
 760         machine_mode mode ATTRIBUTE_UNUSED,
 761         tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
 762 {
 763   return 0;
 764 }
 765
 766 void
 767 hook_void_CUMULATIVE_ARGS_tree (cumulative_args_t ca ATTRIBUTE_UNUSED,
 768                                 tree ATTRIBUTE_UNUSED)
 769 {
 770 }
 771
 772 void
 773 default_function_arg_advance (cumulative_args_t ca ATTRIBUTE_UNUSED,
 774                               machine_mode mode ATTRIBUTE_UNUSED,
 775                               const_tree type ATTRIBUTE_UNUSED,
 776                               bool named ATTRIBUTE_UNUSED)
 777 {
 778   gcc_unreachable ();
 779 }
 780
 781 /* Default implementation of TARGET_FUNCTION_ARG_OFFSET.  */
 782
 783 HOST_WIDE_INT
 784 default_function_arg_offset (machine_mode, const_tree)
 785 {
 786   return 0;
 787 }
 788
 789 /* Default implementation of TARGET_FUNCTION_ARG_PADDING: usually pad
 790    upward, but pad short args downward on big-endian machines.  */
 791
 792 pad_direction
 793 default_function_arg_padding (machine_mode mode, const_tree type)
 794 {
 795   if (!BYTES_BIG_ENDIAN)
 796     return PAD_UPWARD;
 797
 798   unsigned HOST_WIDE_INT size;
 799   if (mode == BLKmode)
 800     {
 801       if (!type || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
 802         return PAD_UPWARD;
 803       size = int_size_in_bytes (type);
 804     }
 805   else
 806     /* Targets with variable-sized modes must override this hook
 807        and handle variable-sized modes explicitly.  */
 808     size = GET_MODE_SIZE (mode).to_constant ();
 809
 810   if (size < (PARM_BOUNDARY / BITS_PER_UNIT))
 811     return PAD_DOWNWARD;
 812
 813   return PAD_UPWARD;
 814 }
 815
 816 rtx
 817 default_function_arg (cumulative_args_t ca ATTRIBUTE_UNUSED,
 818                       machine_mode mode ATTRIBUTE_UNUSED,
 819                       const_tree type ATTRIBUTE_UNUSED,
 820                       bool named ATTRIBUTE_UNUSED)
 821 {
 822   gcc_unreachable ();
 823 }
 824
 825 rtx
 826 default_function_incoming_arg (cumulative_args_t ca ATTRIBUTE_UNUSED,
 827                                machine_mode mode ATTRIBUTE_UNUSED,
 828                                const_tree type ATTRIBUTE_UNUSED,
 829                                bool named ATTRIBUTE_UNUSED)
 830 {
 831   gcc_unreachable ();
 832 }
 833
 834 unsigned int
 835 default_function_arg_boundary (machine_mode mode ATTRIBUTE_UNUSED,
 836                                const_tree type ATTRIBUTE_UNUSED)
 837 {
 838   return PARM_BOUNDARY;
 839 }
 840
 841 unsigned int
 842 default_function_arg_round_boundary (machine_mode mode ATTRIBUTE_UNUSED,
 843                                      const_tree type ATTRIBUTE_UNUSED)
 844 {
 845   return PARM_BOUNDARY;
 846 }
 847
 848 void
 849 hook_void_bitmap (bitmap regs ATTRIBUTE_UNUSED)
 850 {
 851 }
 852
 853 const char *
 854 hook_invalid_arg_for_unprototyped_fn (
 855         const_tree typelist ATTRIBUTE_UNUSED,
 856         const_tree funcdecl ATTRIBUTE_UNUSED,
 857         const_tree val ATTRIBUTE_UNUSED)
 858 {
 859   return NULL;
 860 }
 861
 862 /* Initialize the stack protection decls.  */
 863
 864 /* Stack protection related decls living in libgcc.  */
 865 static GTY(()) tree stack_chk_guard_decl;
 866
 867 tree
 868 default_stack_protect_guard (void)
 869 {
 870   tree t = stack_chk_guard_decl;
 871
 872   if (t == NULL)
 873     {
 874       rtx x;
 875
 876       t = build_decl (UNKNOWN_LOCATION,
 877                       VAR_DECL, get_identifier ("__stack_chk_guard"),
 878                       ptr_type_node);
 879       TREE_STATIC (t) = 1;
 880       TREE_PUBLIC (t) = 1;
 881       DECL_EXTERNAL (t) = 1;
 882       TREE_USED (t) = 1;
 883       TREE_THIS_VOLATILE (t) = 1;
 884       DECL_ARTIFICIAL (t) = 1;
 885       DECL_IGNORED_P (t) = 1;
 886
 887       /* Do not share RTL as the declaration is visible outside of
 888          current function.  */
 889       x = DECL_RTL (t);
 890       RTX_FLAG (x, used) = 1;
 891
 892       stack_chk_guard_decl = t;
 893     }
 894
 895   return t;
 896 }
 897
 898 static GTY(()) tree stack_chk_fail_decl;
 899
 900 tree
 901 default_external_stack_protect_fail (void)
 902 {
 903   tree t = stack_chk_fail_decl;
 904
 905   if (t == NULL_TREE)
 906     {
 907       t = build_function_type_list (void_type_node, NULL_TREE);
 908       t = build_decl (UNKNOWN_LOCATION,
 909                       FUNCTION_DECL, get_identifier ("__stack_chk_fail"), t);
 910       TREE_STATIC (t) = 1;
 911       TREE_PUBLIC (t) = 1;
 912       DECL_EXTERNAL (t) = 1;
 913       TREE_USED (t) = 1;
 914       TREE_THIS_VOLATILE (t) = 1;
 915       TREE_NOTHROW (t) = 1;
 916       DECL_ARTIFICIAL (t) = 1;
 917       DECL_IGNORED_P (t) = 1;
 918       DECL_VISIBILITY (t) = VISIBILITY_DEFAULT;
 919       DECL_VISIBILITY_SPECIFIED (t) = 1;
 920
 921       stack_chk_fail_decl = t;
 922     }
 923
 924   return build_call_expr (t, 0);
 925 }
 926
 927 tree
 928 default_hidden_stack_protect_fail (void)
 929 {
 930 #ifndef HAVE_GAS_HIDDEN
 931   return default_external_stack_protect_fail ();
 932 #else
 933   tree t = stack_chk_fail_decl;
 934
 935   if (!flag_pic)
 936     return default_external_stack_protect_fail ();
 937
 938   if (t == NULL_TREE)
 939     {
 940       t = build_function_type_list (void_type_node, NULL_TREE);
 941       t = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL,
 942                       get_identifier ("__stack_chk_fail_local"), t);
 943       TREE_STATIC (t) = 1;
 944       TREE_PUBLIC (t) = 1;
 945       DECL_EXTERNAL (t) = 1;
 946       TREE_USED (t) = 1;
 947       TREE_THIS_VOLATILE (t) = 1;
 948       TREE_NOTHROW (t) = 1;
 949       DECL_ARTIFICIAL (t) = 1;
 950       DECL_IGNORED_P (t) = 1;
 951       DECL_VISIBILITY_SPECIFIED (t) = 1;
 952       DECL_VISIBILITY (t) = VISIBILITY_HIDDEN;
 953
 954       stack_chk_fail_decl = t;
 955     }
 956
 957   return build_call_expr (t, 0);
 958 #endif
 959 }
 960
 961 bool
 962 hook_bool_const_rtx_commutative_p (const_rtx x,
 963                                    int outer_code ATTRIBUTE_UNUSED)
 964 {
 965   return COMMUTATIVE_P (x);
 966 }
 967
 968 rtx
 969 default_function_value (const_tree ret_type ATTRIBUTE_UNUSED,
 970                         const_tree fn_decl_or_type,
 971                         bool outgoing ATTRIBUTE_UNUSED)
 972 {
 973   /* The old interface doesn't handle receiving the function type.  */
 974   if (fn_decl_or_type
 975       && !DECL_P (fn_decl_or_type))
 976     fn_decl_or_type = NULL;
 977
 978 #ifdef FUNCTION_VALUE
 979   return FUNCTION_VALUE (ret_type, fn_decl_or_type);
 980 #else
 981   gcc_unreachable ();
 982 #endif
 983 }
 984
 985 rtx
 986 default_libcall_value (machine_mode mode ATTRIBUTE_UNUSED,
 987                        const_rtx fun ATTRIBUTE_UNUSED)
 988 {
 989 #ifdef LIBCALL_VALUE
 990   return LIBCALL_VALUE (MACRO_MODE (mode));
 991 #else
 992   gcc_unreachable ();
 993 #endif
 994 }
 995
 996 /* The default hook for TARGET_FUNCTION_VALUE_REGNO_P.  */
 997
 998 bool
 999 default_function_value_regno_p (const unsigned int regno ATTRIBUTE_UNUSED)
1000 {
1001 #ifdef FUNCTION_VALUE_REGNO_P
1002   return FUNCTION_VALUE_REGNO_P (regno);
1003 #else
1004   gcc_unreachable ();
1005 #endif
1006 }
1007
1008 rtx
1009 default_internal_arg_pointer (void)
1010 {
1011   /* If the reg that the virtual arg pointer will be translated into is
1012      not a fixed reg or is the stack pointer, make a copy of the virtual
1013      arg pointer, and address parms via the copy.  The frame pointer is
1014      considered fixed even though it is not marked as such.  */
1015   if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
1016        || ! (fixed_regs[ARG_POINTER_REGNUM]
1017              || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
1018     return copy_to_reg (virtual_incoming_args_rtx);
1019   else
1020     return virtual_incoming_args_rtx;
1021 }
1022
1023 rtx
1024 default_static_chain (const_tree ARG_UNUSED (fndecl_or_type), bool incoming_p)
1025 {
1026   if (incoming_p)
1027     {
1028 #ifdef STATIC_CHAIN_INCOMING_REGNUM
1029       return gen_rtx_REG (Pmode, STATIC_CHAIN_INCOMING_REGNUM);
1030 #endif
1031     }
1032
1033 #ifdef STATIC_CHAIN_REGNUM
1034   return gen_rtx_REG (Pmode, STATIC_CHAIN_REGNUM);
1035 #endif
1036
1037   {
1038     static bool issued_error;
1039     if (!issued_error)
1040       {
1041         issued_error = true;
1042         sorry ("nested functions not supported on this target");
1043       }
1044
1045     /* It really doesn't matter what we return here, so long at it
1046        doesn't cause the rest of the compiler to crash.  */
1047     return gen_rtx_MEM (Pmode, stack_pointer_rtx);
1048   }
1049 }
1050
1051 void
1052 default_trampoline_init (rtx ARG_UNUSED (m_tramp), tree ARG_UNUSED (t_func),
1053                          rtx ARG_UNUSED (r_chain))
1054 {
1055   sorry ("nested function trampolines not supported on this target");
1056 }
1057
1058 poly_int64
1059 default_return_pops_args (tree, tree, poly_int64)
1060 {
1061   return 0;
1062 }
1063
1064 reg_class_t
1065 default_branch_target_register_class (void)
1066 {
1067   return NO_REGS;
1068 }
1069
1070 reg_class_t
1071 default_ira_change_pseudo_allocno_class (int regno ATTRIBUTE_UNUSED,
1072                                          reg_class_t cl,
1073                                          reg_class_t best_cl ATTRIBUTE_UNUSED)
1074 {
1075   return cl;
1076 }
1077
1078 extern bool
1079 default_lra_p (void)
1080 {
1081   return true;
1082 }
1083
1084 int
1085 default_register_priority (int hard_regno ATTRIBUTE_UNUSED)
1086 {
1087   return 0;
1088 }
1089
1090 extern bool
1091 default_register_usage_leveling_p (void)
1092 {
1093   return false;
1094 }
1095
1096 extern bool
1097 default_different_addr_displacement_p (void)
1098 {
1099   return false;
1100 }
1101
1102 reg_class_t
1103 default_secondary_reload (bool in_p ATTRIBUTE_UNUSED, rtx x ATTRIBUTE_UNUSED,
1104                           reg_class_t reload_class_i ATTRIBUTE_UNUSED,
1105                           machine_mode reload_mode ATTRIBUTE_UNUSED,
1106                           secondary_reload_info *sri)
1107 {
1108   enum reg_class rclass = NO_REGS;
1109   enum reg_class reload_class = (enum reg_class) reload_class_i;
1110
1111   if (sri->prev_sri && sri->prev_sri->t_icode != CODE_FOR_nothing)
1112     {
1113       sri->icode = sri->prev_sri->t_icode;
1114       return NO_REGS;
1115     }
1116 #ifdef SECONDARY_INPUT_RELOAD_CLASS
1117   if (in_p)
1118     rclass = SECONDARY_INPUT_RELOAD_CLASS (reload_class,
1119                                            MACRO_MODE (reload_mode), x);
1120 #endif
1121 #ifdef SECONDARY_OUTPUT_RELOAD_CLASS
1122   if (! in_p)
1123     rclass = SECONDARY_OUTPUT_RELOAD_CLASS (reload_class,
1124                                             MACRO_MODE (reload_mode), x);
1125 #endif
1126   if (rclass != NO_REGS)
1127     {
1128       enum insn_code icode
1129         = direct_optab_handler (in_p ? reload_in_optab : reload_out_optab,
1130                                 reload_mode);
1131
1132       if (icode != CODE_FOR_nothing
1133           && !insn_operand_matches (icode, in_p, x))
1134         icode = CODE_FOR_nothing;
1135       else if (icode != CODE_FOR_nothing)
1136         {
1137           const char *insn_constraint, *scratch_constraint;
1138           enum reg_class insn_class, scratch_class;
1139
1140           gcc_assert (insn_data[(int) icode].n_operands == 3);
1141           insn_constraint = insn_data[(int) icode].operand[!in_p].constraint;
1142           if (!*insn_constraint)
1143             insn_class = ALL_REGS;
1144           else
1145             {
1146               if (in_p)
1147                 {
1148                   gcc_assert (*insn_constraint == '=');
1149                   insn_constraint++;
1150                 }
1151               insn_class = (reg_class_for_constraint
1152                             (lookup_constraint (insn_constraint)));
1153               gcc_assert (insn_class != NO_REGS);
1154             }
1155
1156           scratch_constraint = insn_data[(int) icode].operand[2].constraint;
1157           /* The scratch register's constraint must start with "=&",
1158              except for an input reload, where only "=" is necessary,
1159              and where it might be beneficial to re-use registers from
1160              the input.  */
1161           gcc_assert (scratch_constraint[0] == '='
1162                       && (in_p || scratch_constraint[1] == '&'));
1163           scratch_constraint++;
1164           if (*scratch_constraint == '&')
1165             scratch_constraint++;
1166           scratch_class = (reg_class_for_constraint
1167                            (lookup_constraint (scratch_constraint)));
1168
1169           if (reg_class_subset_p (reload_class, insn_class))
1170             {
1171               gcc_assert (scratch_class == rclass);
1172               rclass = NO_REGS;
1173             }
1174           else
1175             rclass = insn_class;
1176
1177         }
1178       if (rclass == NO_REGS)
1179         sri->icode = icode;
1180       else
1181         sri->t_icode = icode;
1182     }
1183   return rclass;
1184 }
1185
1186 /* The default implementation of TARGET_SECONDARY_MEMORY_NEEDED_MODE.  */
1187
1188 machine_mode
1189 default_secondary_memory_needed_mode (machine_mode mode)
1190 {
1191   if (!targetm.lra_p ()
1192       && known_lt (GET_MODE_BITSIZE (mode), BITS_PER_WORD)
1193       && INTEGRAL_MODE_P (mode))
1194     return mode_for_size (BITS_PER_WORD, GET_MODE_CLASS (mode), 0).require ();
1195   return mode;
1196 }
1197
1198 /* By default, if flag_pic is true, then neither local nor global relocs
1199    should be placed in readonly memory.  */
1200
1201 int
1202 default_reloc_rw_mask (void)
1203 {
1204   return flag_pic ? 3 : 0;
1205 }
1206
1207 /* By default, address diff vectors are generated
1208 for jump tables when flag_pic is true.  */
1209
1210 bool
1211 default_generate_pic_addr_diff_vec (void)
1212 {
1213   return flag_pic;
1214 }
1215
1216 /* By default, do no modification. */
1217 tree default_mangle_decl_assembler_name (tree decl ATTRIBUTE_UNUSED,
1218                                          tree id)
1219 {
1220    return id;
1221 }
1222
1223 /* The default implementation of TARGET_STATIC_RTX_ALIGNMENT.  */
1224
1225 HOST_WIDE_INT
1226 default_static_rtx_alignment (machine_mode mode)
1227 {
1228   return GET_MODE_ALIGNMENT (mode);
1229 }
1230
1231 /* The default implementation of TARGET_CONSTANT_ALIGNMENT.  */
1232
1233 HOST_WIDE_INT
1234 default_constant_alignment (const_tree, HOST_WIDE_INT align)
1235 {
1236   return align;
1237 }
1238
1239 /* An implementation of TARGET_CONSTANT_ALIGNMENT that aligns strings
1240    to at least BITS_PER_WORD but otherwise makes no changes.  */
1241
1242 HOST_WIDE_INT
1243 constant_alignment_word_strings (const_tree exp, HOST_WIDE_INT align)
1244 {
1245   if (TREE_CODE (exp) == STRING_CST)
1246     return MAX (align, BITS_PER_WORD);
1247   return align;
1248 }
1249
1250 /* Default to natural alignment for vector types, bounded by
1251    MAX_OFILE_ALIGNMENT.  */
1252
1253 HOST_WIDE_INT
1254 default_vector_alignment (const_tree type)
1255 {
1256   unsigned HOST_WIDE_INT align = MAX_OFILE_ALIGNMENT;
1257   tree size = TYPE_SIZE (type);
1258   if (tree_fits_uhwi_p (size))
1259     align = tree_to_uhwi (size);
1260
1261   return align < MAX_OFILE_ALIGNMENT ? align : MAX_OFILE_ALIGNMENT;
1262 }
1263
1264 /* The default implementation of
1265    TARGET_VECTORIZE_PREFERRED_VECTOR_ALIGNMENT.  */
1266
1267 poly_uint64
1268 default_preferred_vector_alignment (const_tree type)
1269 {
1270   return TYPE_ALIGN (type);
1271 }
1272
1273 /* By default assume vectors of element TYPE require a multiple of the natural
1274    alignment of TYPE.  TYPE is naturally aligned if IS_PACKED is false.  */
1275 bool
1276 default_builtin_vector_alignment_reachable (const_tree /*type*/, bool is_packed)
1277 {
1278   return ! is_packed;
1279 }
1280
1281 /* By default, assume that a target supports any factor of misalignment
1282    memory access if it supports movmisalign patten.
1283    is_packed is true if the memory access is defined in a packed struct.  */
1284 bool
1285 default_builtin_support_vector_misalignment (machine_mode mode,
1286                                              const_tree type
1287                                              ATTRIBUTE_UNUSED,
1288                                              int misalignment
1289                                              ATTRIBUTE_UNUSED,
1290                                              bool is_packed
1291                                              ATTRIBUTE_UNUSED)
1292 {
1293   if (optab_handler (movmisalign_optab, mode) != CODE_FOR_nothing)
1294     return true;
1295   return false;
1296 }
1297
1298 /* By default, only attempt to parallelize bitwise operations, and
1299    possibly adds/subtracts using bit-twiddling.  */
1300
1301 machine_mode
1302 default_preferred_simd_mode (scalar_mode)
1303 {
1304   return word_mode;
1305 }
1306
1307 /* By default do not split reductions further.  */
1308
1309 machine_mode
1310 default_split_reduction (machine_mode mode)
1311 {
1312   return mode;
1313 }
1314
1315 /* By default only the size derived from the preferred vector mode
1316    is tried.  */
1317
1318 void
1319 default_autovectorize_vector_sizes (vector_sizes *, bool)
1320 {
1321 }
1322
1323 /* By default a vector of integers is used as a mask.  */
1324
1325 opt_machine_mode
1326 default_get_mask_mode (poly_uint64 nunits, poly_uint64 vector_size)
1327 {
1328   unsigned int elem_size = vector_element_size (vector_size, nunits);
1329   scalar_int_mode elem_mode
1330     = smallest_int_mode_for_size (elem_size * BITS_PER_UNIT);
1331   machine_mode vector_mode;
1332
1333   gcc_assert (known_eq (elem_size * nunits, vector_size));
1334
1335   if (mode_for_vector (elem_mode, nunits).exists (&vector_mode)
1336       && VECTOR_MODE_P (vector_mode)
1337       && targetm.vector_mode_supported_p (vector_mode))
1338     return vector_mode;
1339
1340   return opt_machine_mode ();
1341 }
1342
1343 /* By default consider masked stores to be expensive.  */
1344
1345 bool
1346 default_empty_mask_is_expensive (unsigned ifn)
1347 {
1348   return ifn == IFN_MASK_STORE;
1349 }
1350
1351 /* By default, the cost model accumulates three separate costs (prologue,
1352    loop body, and epilogue) for a vectorized loop or block.  So allocate an
1353    array of three unsigned ints, set it to zero, and return its address.  */
1354
1355 void *
1356 default_init_cost (struct loop *loop_info ATTRIBUTE_UNUSED)
1357 {
1358   unsigned *cost = XNEWVEC (unsigned, 3);
1359   cost[vect_prologue] = cost[vect_body] = cost[vect_epilogue] = 0;
1360   return cost;
1361 }
1362
1363 /* By default, the cost model looks up the cost of the given statement
1364    kind and mode, multiplies it by the occurrence count, accumulates
1365    it into the cost specified by WHERE, and returns the cost added.  */
1366
1367 unsigned
1368 default_add_stmt_cost (void *data, int count, enum vect_cost_for_stmt kind,
1369                        struct _stmt_vec_info *stmt_info, int misalign,
1370                        enum vect_cost_model_location where)
1371 {
1372   unsigned *cost = (unsigned *) data;
1373   unsigned retval = 0;
1374
1375   tree vectype = stmt_info ? stmt_vectype (stmt_info) : NULL_TREE;
1376   int stmt_cost = targetm.vectorize.builtin_vectorization_cost (kind, vectype,
1377                                                                 misalign);
1378    /* Statements in an inner loop relative to the loop being
1379       vectorized are weighted more heavily.  The value here is
1380       arbitrary and could potentially be improved with analysis.  */
1381   if (where == vect_body && stmt_info && stmt_in_inner_loop_p (stmt_info))
1382     count *= 50;  /* FIXME.  */
1383
1384   retval = (unsigned) (count * stmt_cost);
1385   cost[where] += retval;
1386
1387   return retval;
1388 }
1389
1390 /* By default, the cost model just returns the accumulated costs.  */
1391
1392 void
1393 default_finish_cost (void *data, unsigned *prologue_cost,
1394                      unsigned *body_cost, unsigned *epilogue_cost)
1395 {
1396   unsigned *cost = (unsigned *) data;
1397   *prologue_cost = cost[vect_prologue];
1398   *body_cost     = cost[vect_body];
1399   *epilogue_cost = cost[vect_epilogue];
1400 }
1401
1402 /* Free the cost data.  */
1403
1404 void
1405 default_destroy_cost_data (void *data)
1406 {
1407   free (data);
1408 }
1409
1410 /* Determine whether or not a pointer mode is valid. Assume defaults
1411    of ptr_mode or Pmode - can be overridden.  */
1412 bool
1413 default_valid_pointer_mode (scalar_int_mode mode)
1414 {
1415   return (mode == ptr_mode || mode == Pmode);
1416 }
1417
1418 /* Determine whether the memory reference specified by REF may alias
1419    the C libraries errno location.  */
1420 bool
1421 default_ref_may_alias_errno (ao_ref *ref)
1422 {
1423   tree base = ao_ref_base (ref);
1424   /* The default implementation assumes the errno location is
1425      a declaration of type int or is always accessed via a
1426      pointer to int.  We assume that accesses to errno are
1427      not deliberately obfuscated (even in conforming ways).  */
1428   if (TYPE_UNSIGNED (TREE_TYPE (base))
1429       || TYPE_MODE (TREE_TYPE (base)) != TYPE_MODE (integer_type_node))
1430     return false;
1431   /* The default implementation assumes an errno location
1432      declaration is never defined in the current compilation unit.  */
1433   if (DECL_P (base)
1434       && !TREE_STATIC (base))
1435     return true;
1436   else if (TREE_CODE (base) == MEM_REF
1437            && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME)
1438     {
1439       struct ptr_info_def *pi = SSA_NAME_PTR_INFO (TREE_OPERAND (base, 0));
1440       return !pi || pi->pt.anything || pi->pt.nonlocal;
1441     }
1442   return false;
1443 }
1444
1445 /* Return the mode for a pointer to a given ADDRSPACE,
1446    defaulting to ptr_mode for all address spaces.  */
1447
1448 scalar_int_mode
1449 default_addr_space_pointer_mode (addr_space_t addrspace ATTRIBUTE_UNUSED)
1450 {
1451   return ptr_mode;
1452 }
1453
1454 /* Return the mode for an address in a given ADDRSPACE,
1455    defaulting to Pmode for all address spaces.  */
1456
1457 scalar_int_mode
1458 default_addr_space_address_mode (addr_space_t addrspace ATTRIBUTE_UNUSED)
1459 {
1460   return Pmode;
1461 }
1462
1463 /* Named address space version of valid_pointer_mode.
1464    To match the above, the same modes apply to all address spaces.  */
1465
1466 bool
1467 default_addr_space_valid_pointer_mode (scalar_int_mode mode,
1468                                        addr_space_t as ATTRIBUTE_UNUSED)
1469 {
1470   return targetm.valid_pointer_mode (mode);
1471 }
1472
1473 /* Some places still assume that all pointer or address modes are the
1474    standard Pmode and ptr_mode.  These optimizations become invalid if
1475    the target actually supports multiple different modes.  For now,
1476    we disable such optimizations on such targets, using this function.  */
1477
1478 bool
1479 target_default_pointer_address_modes_p (void)
1480 {
1481   if (targetm.addr_space.address_mode != default_addr_space_address_mode)
1482     return false;
1483   if (targetm.addr_space.pointer_mode != default_addr_space_pointer_mode)
1484     return false;
1485
1486   return true;
1487 }
1488
1489 /* Named address space version of legitimate_address_p.
1490    By default, all address spaces have the same form.  */
1491
1492 bool
1493 default_addr_space_legitimate_address_p (machine_mode mode, rtx mem,
1494                                          bool strict,
1495                                          addr_space_t as ATTRIBUTE_UNUSED)
1496 {
1497   return targetm.legitimate_address_p (mode, mem, strict);
1498 }
1499
1500 /* Named address space version of LEGITIMIZE_ADDRESS.
1501    By default, all address spaces have the same form.  */
1502
1503 rtx
1504 default_addr_space_legitimize_address (rtx x, rtx oldx, machine_mode mode,
1505                                        addr_space_t as ATTRIBUTE_UNUSED)
1506 {
1507   return targetm.legitimize_address (x, oldx, mode);
1508 }
1509
1510 /* The default hook for determining if one named address space is a subset of
1511    another and to return which address space to use as the common address
1512    space.  */
1513
1514 bool
1515 default_addr_space_subset_p (addr_space_t subset, addr_space_t superset)
1516 {
1517   return (subset == superset);
1518 }
1519
1520 /* The default hook for determining if 0 within a named address
1521    space is a valid address.  */
1522
1523 bool
1524 default_addr_space_zero_address_valid (addr_space_t as ATTRIBUTE_UNUSED)
1525 {
1526   return false;
1527 }
1528
1529 /* The default hook for debugging the address space is to return the
1530    address space number to indicate DW_AT_address_class.  */
1531 int
1532 default_addr_space_debug (addr_space_t as)
1533 {
1534   return as;
1535 }
1536
1537 /* The default hook implementation for TARGET_ADDR_SPACE_DIAGNOSE_USAGE.
1538    Don't complain about any address space.  */
1539
1540 void
1541 default_addr_space_diagnose_usage (addr_space_t, location_t)
1542 {
1543 }
1544
1545
1546 /* The default hook for TARGET_ADDR_SPACE_CONVERT. This hook should never be
1547    called for targets with only a generic address space.  */
1548
1549 rtx
1550 default_addr_space_convert (rtx op ATTRIBUTE_UNUSED,
1551                             tree from_type ATTRIBUTE_UNUSED,
1552                             tree to_type ATTRIBUTE_UNUSED)
1553 {
1554   gcc_unreachable ();
1555 }
1556
1557 /* The defualt implementation of TARGET_HARD_REGNO_NREGS.  */
1558
1559 unsigned int
1560 default_hard_regno_nregs (unsigned int, machine_mode mode)
1561 {
1562   /* Targets with variable-sized modes must provide their own definition
1563      of this hook.  */
1564   return CEIL (GET_MODE_SIZE (mode).to_constant (), UNITS_PER_WORD);
1565 }
1566
1567 bool
1568 default_hard_regno_scratch_ok (unsigned int regno ATTRIBUTE_UNUSED)
1569 {
1570   return true;
1571 }
1572
1573 /* The default implementation of TARGET_MODE_DEPENDENT_ADDRESS_P.  */
1574
1575 bool
1576 default_mode_dependent_address_p (const_rtx addr ATTRIBUTE_UNUSED,
1577                                   addr_space_t addrspace ATTRIBUTE_UNUSED)
1578 {
1579   return false;
1580 }
1581
1582 bool
1583 default_target_option_valid_attribute_p (tree ARG_UNUSED (fndecl),
1584                                          tree ARG_UNUSED (name),
1585                                          tree ARG_UNUSED (args),
1586                                          int ARG_UNUSED (flags))
1587 {
1588   warning (OPT_Wattributes,
1589            "target attribute is not supported on this machine");
1590
1591   return false;
1592 }
1593
1594 bool
1595 default_target_option_pragma_parse (tree ARG_UNUSED (args),
1596                                     tree ARG_UNUSED (pop_target))
1597 {
1598   /* If args is NULL the caller is handle_pragma_pop_options ().  In that case,
1599      emit no warning because "#pragma GCC pop_target" is valid on targets that
1600      do not have the "target" pragma.  */
1601   if (args)
1602     warning (OPT_Wpragmas,
1603              "%<#pragma GCC target%> is not supported for this machine");
1604
1605   return false;
1606 }
1607
1608 bool
1609 default_target_can_inline_p (tree caller, tree callee)
1610 {
1611   tree callee_opts = DECL_FUNCTION_SPECIFIC_TARGET (callee);
1612   tree caller_opts = DECL_FUNCTION_SPECIFIC_TARGET (caller);
1613   if (! callee_opts)
1614     callee_opts = target_option_default_node;
1615   if (! caller_opts)
1616     caller_opts = target_option_default_node;
1617
1618   /* If both caller and callee have attributes, assume that if the
1619      pointer is different, the two functions have different target
1620      options since build_target_option_node uses a hash table for the
1621      options.  */
1622   return callee_opts == caller_opts;
1623 }
1624
1625 /* If the machine does not have a case insn that compares the bounds,
1626    this means extra overhead for dispatch tables, which raises the
1627    threshold for using them.  */
1628
1629 unsigned int
1630 default_case_values_threshold (void)
1631 {
1632   return (targetm.have_casesi () ? 4 : 5);
1633 }
1634
1635 bool
1636 default_have_conditional_execution (void)
1637 {
1638   return HAVE_conditional_execution;
1639 }
1640
1641 /* By default we assume that c99 functions are present at the runtime,
1642    but sincos is not.  */
1643 bool
1644 default_libc_has_function (enum function_class fn_class)
1645 {
1646   if (fn_class == function_c94
1647       || fn_class == function_c99_misc
1648       || fn_class == function_c99_math_complex)
1649     return true;
1650
1651   return false;
1652 }
1653
1654 /* By default assume that libc has not a fast implementation.  */
1655
1656 bool
1657 default_libc_has_fast_function (int fcode ATTRIBUTE_UNUSED)
1658 {
1659   return false;
1660 }
1661
1662 bool
1663 gnu_libc_has_function (enum function_class fn_class ATTRIBUTE_UNUSED)
1664 {
1665   return true;
1666 }
1667
1668 bool
1669 no_c99_libc_has_function (enum function_class fn_class ATTRIBUTE_UNUSED)
1670 {
1671   return false;
1672 }
1673
1674 tree
1675 default_builtin_tm_load_store (tree ARG_UNUSED (type))
1676 {
1677   return NULL_TREE;
1678 }
1679
1680 /* Compute cost of moving registers to/from memory.  */
1681
1682 int
1683 default_memory_move_cost (machine_mode mode ATTRIBUTE_UNUSED,
1684                           reg_class_t rclass ATTRIBUTE_UNUSED,
1685                           bool in ATTRIBUTE_UNUSED)
1686 {
1687 #ifndef MEMORY_MOVE_COST
1688     return (4 + memory_move_secondary_cost (mode, (enum reg_class) rclass, in));
1689 #else
1690     return MEMORY_MOVE_COST (MACRO_MODE (mode), (enum reg_class) rclass, in);
1691 #endif
1692 }
1693
1694 /* Compute cost of moving data from a register of class FROM to one of
1695    TO, using MODE.  */
1696
1697 int
1698 default_register_move_cost (machine_mode mode ATTRIBUTE_UNUSED,
1699                             reg_class_t from ATTRIBUTE_UNUSED,
1700                             reg_class_t to ATTRIBUTE_UNUSED)
1701 {
1702 #ifndef REGISTER_MOVE_COST
1703   return 2;
1704 #else
1705   return REGISTER_MOVE_COST (MACRO_MODE (mode),
1706                              (enum reg_class) from, (enum reg_class) to);
1707 #endif
1708 }
1709
1710 /* The default implementation of TARGET_SLOW_UNALIGNED_ACCESS.  */
1711
1712 bool
1713 default_slow_unaligned_access (machine_mode, unsigned int)
1714 {
1715   return STRICT_ALIGNMENT;
1716 }
1717
1718 /* The default implementation of TARGET_ESTIMATED_POLY_VALUE.  */
1719
1720 HOST_WIDE_INT
1721 default_estimated_poly_value (poly_int64 x)
1722 {
1723   return x.coeffs[0];
1724 }
1725
1726 /* For hooks which use the MOVE_RATIO macro, this gives the legacy default
1727    behavior.  SPEED_P is true if we are compiling for speed.  */
1728
1729 unsigned int
1730 get_move_ratio (bool speed_p ATTRIBUTE_UNUSED)
1731 {
1732   unsigned int move_ratio;
1733 #ifdef MOVE_RATIO
1734   move_ratio = (unsigned int) MOVE_RATIO (speed_p);
1735 #else
1736 #if defined (HAVE_movmemqi) || defined (HAVE_movmemhi) || defined (HAVE_movmemsi) || defined (HAVE_movmemdi) || defined (HAVE_movmemti)
1737   move_ratio = 2;
1738 #else /* No movmem patterns, pick a default.  */
1739   move_ratio = ((speed_p) ? 15 : 3);
1740 #endif
1741 #endif
1742   return move_ratio;
1743 }
1744
1745 /* Return TRUE if the move_by_pieces/set_by_pieces infrastructure should be
1746    used; return FALSE if the movmem/setmem optab should be expanded, or
1747    a call to memcpy emitted.  */
1748
1749 bool
1750 default_use_by_pieces_infrastructure_p (unsigned HOST_WIDE_INT size,
1751                                         unsigned int alignment,
1752                                         enum by_pieces_operation op,
1753                                         bool speed_p)
1754 {
1755   unsigned int max_size = 0;
1756   unsigned int ratio = 0;
1757
1758   switch (op)
1759     {
1760     case CLEAR_BY_PIECES:
1761       max_size = STORE_MAX_PIECES;
1762       ratio = CLEAR_RATIO (speed_p);
1763       break;
1764     case MOVE_BY_PIECES:
1765       max_size = MOVE_MAX_PIECES;
1766       ratio = get_move_ratio (speed_p);
1767       break;
1768     case SET_BY_PIECES:
1769       max_size = STORE_MAX_PIECES;
1770       ratio = SET_RATIO (speed_p);
1771       break;
1772     case STORE_BY_PIECES:
1773       max_size = STORE_MAX_PIECES;
1774       ratio = get_move_ratio (speed_p);
1775       break;
1776     case COMPARE_BY_PIECES:
1777       max_size = COMPARE_MAX_PIECES;
1778       /* Pick a likely default, just as in get_move_ratio.  */
1779       ratio = speed_p ? 15 : 3;
1780       break;
1781     }
1782
1783   return by_pieces_ninsns (size, alignment, max_size + 1, op) < ratio;
1784 }
1785
1786 /* This hook controls code generation for expanding a memcmp operation by
1787    pieces.  Return 1 for the normal pattern of compare/jump after each pair
1788    of loads, or a higher number to reduce the number of branches.  */
1789
1790 int
1791 default_compare_by_pieces_branch_ratio (machine_mode)
1792 {
1793   return 1;
1794 }
1795
1796 /* Write PATCH_AREA_SIZE NOPs into the asm outfile FILE around a function
1797    entry.  If RECORD_P is true and the target supports named sections,
1798    the location of the NOPs will be recorded in a special object section
1799    called "__patchable_function_entries".  This routine may be called
1800    twice per function to put NOPs before and after the function
1801    entry.  */
1802
1803 void
1804 default_print_patchable_function_entry (FILE *file,
1805                                         unsigned HOST_WIDE_INT patch_area_size,
1806                                         bool record_p)
1807 {
1808   const char *nop_templ = 0;
1809   int code_num;
1810   rtx_insn *my_nop = make_insn_raw (gen_nop ());
1811
1812   /* We use the template alone, relying on the (currently sane) assumption
1813      that the NOP template does not have variable operands.  */
1814   code_num = recog_memoized (my_nop);
1815   nop_templ = get_insn_template (code_num, my_nop);
1816
1817   if (record_p && targetm_common.have_named_sections)
1818     {
1819       char buf[256];
1820       static int patch_area_number;
1821       section *previous_section = in_section;
1822       const char *asm_op = integer_asm_op (POINTER_SIZE_UNITS, false);
1823
1824       gcc_assert (asm_op != NULL);
1825       patch_area_number++;
1826       ASM_GENERATE_INTERNAL_LABEL (buf, "LPFE", patch_area_number);
1827
1828       switch_to_section (get_section ("__patchable_function_entries",
1829                                       SECTION_WRITE | SECTION_RELRO, NULL));
1830       fputs (asm_op, file);
1831       assemble_name_raw (file, buf);
1832       fputc ('\n', file);
1833
1834       switch_to_section (previous_section);
1835       ASM_OUTPUT_LABEL (file, buf);
1836     }
1837
1838   unsigned i;
1839   for (i = 0; i < patch_area_size; ++i)
1840     fprintf (file, "\t%s\n", nop_templ);
1841 }
1842
1843 bool
1844 default_profile_before_prologue (void)
1845 {
1846 #ifdef PROFILE_BEFORE_PROLOGUE
1847   return true;
1848 #else
1849   return false;
1850 #endif
1851 }
1852
1853 /* The default implementation of TARGET_PREFERRED_RELOAD_CLASS.  */
1854
1855 reg_class_t
1856 default_preferred_reload_class (rtx x ATTRIBUTE_UNUSED,
1857                                 reg_class_t rclass)
1858 {
1859 #ifdef PREFERRED_RELOAD_CLASS
1860   return (reg_class_t) PREFERRED_RELOAD_CLASS (x, (enum reg_class) rclass);
1861 #else
1862   return rclass;
1863 #endif
1864 }
1865
1866 /* The default implementation of TARGET_OUTPUT_PREFERRED_RELOAD_CLASS.  */
1867
1868 reg_class_t
1869 default_preferred_output_reload_class (rtx x ATTRIBUTE_UNUSED,
1870                                        reg_class_t rclass)
1871 {
1872   return rclass;
1873 }
1874
1875 /* The default implementation of TARGET_PREFERRED_RENAME_CLASS.  */
1876 reg_class_t
1877 default_preferred_rename_class (reg_class_t rclass ATTRIBUTE_UNUSED)
1878 {
1879   return NO_REGS;
1880 }
1881
1882 /* The default implementation of TARGET_CLASS_LIKELY_SPILLED_P.  */
1883
1884 bool
1885 default_class_likely_spilled_p (reg_class_t rclass)
1886 {
1887   return (reg_class_size[(int) rclass] == 1);
1888 }
1889
1890 /* The default implementation of TARGET_CLASS_MAX_NREGS.  */
1891
1892 unsigned char
1893 default_class_max_nregs (reg_class_t rclass ATTRIBUTE_UNUSED,
1894                          machine_mode mode ATTRIBUTE_UNUSED)
1895 {
1896 #ifdef CLASS_MAX_NREGS
1897   return (unsigned char) CLASS_MAX_NREGS ((enum reg_class) rclass,
1898                                           MACRO_MODE (mode));
1899 #else
1900   /* Targets with variable-sized modes must provide their own definition
1901      of this hook.  */
1902   unsigned int size = GET_MODE_SIZE (mode).to_constant ();
1903   return (size + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
1904 #endif
1905 }
1906
1907 /* Determine the debugging unwind mechanism for the target.  */
1908
1909 enum unwind_info_type
1910 default_debug_unwind_info (void)
1911 {
1912   /* If the target wants to force the use of dwarf2 unwind info, let it.  */
1913   /* ??? Change all users to the hook, then poison this.  */
1914 #ifdef DWARF2_FRAME_INFO
1915   if (DWARF2_FRAME_INFO)
1916     return UI_DWARF2;
1917 #endif
1918
1919   /* Otherwise, only turn it on if dwarf2 debugging is enabled.  */
1920 #ifdef DWARF2_DEBUGGING_INFO
1921   if (write_symbols == DWARF2_DEBUG || write_symbols == VMS_AND_DWARF2_DEBUG)
1922     return UI_DWARF2;
1923 #endif
1924
1925   return UI_NONE;
1926 }
1927
1928 /* Targets that set NUM_POLY_INT_COEFFS to something greater than 1
1929    must define this hook.  */
1930
1931 unsigned int
1932 default_dwarf_poly_indeterminate_value (unsigned int, unsigned int *, int *)
1933 {
1934   gcc_unreachable ();
1935 }
1936
1937 /* Determine the correct mode for a Dwarf frame register that represents
1938    register REGNO.  */
1939
1940 machine_mode
1941 default_dwarf_frame_reg_mode (int regno)
1942 {
1943   machine_mode save_mode = reg_raw_mode[regno];
1944
1945   if (targetm.hard_regno_call_part_clobbered (NULL, regno, save_mode))
1946     save_mode = choose_hard_reg_mode (regno, 1, true);
1947   return save_mode;
1948 }
1949
1950 /* To be used by targets where reg_raw_mode doesn't return the right
1951    mode for registers used in apply_builtin_return and apply_builtin_arg.  */
1952
1953 fixed_size_mode
1954 default_get_reg_raw_mode (int regno)
1955 {
1956   /* Targets must override this hook if the underlying register is
1957      variable-sized.  */
1958   return as_a <fixed_size_mode> (reg_raw_mode[regno]);
1959 }
1960
1961 /* Return true if a leaf function should stay leaf even with profiling
1962    enabled.  */
1963
1964 bool
1965 default_keep_leaf_when_profiled ()
1966 {
1967   return false;
1968 }
1969
1970 /* Return true if the state of option OPTION should be stored in PCH files
1971    and checked by default_pch_valid_p.  Store the option's current state
1972    in STATE if so.  */
1973
1974 static inline bool
1975 option_affects_pch_p (int option, struct cl_option_state *state)
1976 {
1977   if ((cl_options[option].flags & CL_TARGET) == 0)
1978     return false;
1979   if ((cl_options[option].flags & CL_PCH_IGNORE) != 0)
1980     return false;
1981   if (option_flag_var (option, &global_options) == &target_flags)
1982     if (targetm.check_pch_target_flags)
1983       return false;
1984   return get_option_state (&global_options, option, state);
1985 }
1986
1987 /* Default version of get_pch_validity.
1988    By default, every flag difference is fatal; that will be mostly right for
1989    most targets, but completely right for very few.  */
1990
1991 void *
1992 default_get_pch_validity (size_t *sz)
1993 {
1994   struct cl_option_state state;
1995   size_t i;
1996   char *result, *r;
1997
1998   *sz = 2;
1999   if (targetm.check_pch_target_flags)
2000     *sz += sizeof (target_flags);
2001   for (i = 0; i < cl_options_count; i++)
2002     if (option_affects_pch_p (i, &state))
2003       *sz += state.size;
2004
2005   result = r = XNEWVEC (char, *sz);
2006   r[0] = flag_pic;
2007   r[1] = flag_pie;
2008   r += 2;
2009   if (targetm.check_pch_target_flags)
2010     {
2011       memcpy (r, &target_flags, sizeof (target_flags));
2012       r += sizeof (target_flags);
2013     }
2014
2015   for (i = 0; i < cl_options_count; i++)
2016     if (option_affects_pch_p (i, &state))
2017       {
2018         memcpy (r, state.data, state.size);
2019         r += state.size;
2020       }
2021
2022   return result;
2023 }
2024
2025 /* Return a message which says that a PCH file was created with a different
2026    setting of OPTION.  */
2027
2028 static const char *
2029 pch_option_mismatch (const char *option)
2030 {
2031   return xasprintf (_("created and used with differing settings of '%s'"),
2032                     option);
2033 }
2034
2035 /* Default version of pch_valid_p.  */
2036
2037 const char *
2038 default_pch_valid_p (const void *data_p, size_t len)
2039 {
2040   struct cl_option_state state;
2041   const char *data = (const char *)data_p;
2042   size_t i;
2043
2044   /* -fpic and -fpie also usually make a PCH invalid.  */
2045   if (data[0] != flag_pic)
2046     return _("created and used with different settings of %<-fpic%>");
2047   if (data[1] != flag_pie)
2048     return _("created and used with different settings of %<-fpie%>");
2049   data += 2;
2050
2051   /* Check target_flags.  */
2052   if (targetm.check_pch_target_flags)
2053     {
2054       int tf;
2055       const char *r;
2056
2057       memcpy (&tf, data, sizeof (target_flags));
2058       data += sizeof (target_flags);
2059       len -= sizeof (target_flags);
2060       r = targetm.check_pch_target_flags (tf);
2061       if (r != NULL)
2062         return r;
2063     }
2064
2065   for (i = 0; i < cl_options_count; i++)
2066     if (option_affects_pch_p (i, &state))
2067       {
2068         if (memcmp (data, state.data, state.size) != 0)
2069           return pch_option_mismatch (cl_options[i].opt_text);
2070         data += state.size;
2071         len -= state.size;
2072       }
2073
2074   return NULL;
2075 }
2076
2077 /* Default version of cstore_mode.  */
2078
2079 scalar_int_mode
2080 default_cstore_mode (enum insn_code icode)
2081 {
2082   return as_a <scalar_int_mode> (insn_data[(int) icode].operand[0].mode);
2083 }
2084
2085 /* Default version of member_type_forces_blk.  */
2086
2087 bool
2088 default_member_type_forces_blk (const_tree, machine_mode)
2089 {
2090   return false;
2091 }
2092
2093 rtx
2094 default_load_bounds_for_arg (rtx addr ATTRIBUTE_UNUSED,
2095                              rtx ptr ATTRIBUTE_UNUSED,
2096                              rtx bnd ATTRIBUTE_UNUSED)
2097 {
2098   gcc_unreachable ();
2099 }
2100
2101 void
2102 default_store_bounds_for_arg (rtx val ATTRIBUTE_UNUSED,
2103                               rtx addr ATTRIBUTE_UNUSED,
2104                               rtx bounds ATTRIBUTE_UNUSED,
2105                               rtx to ATTRIBUTE_UNUSED)
2106 {
2107   gcc_unreachable ();
2108 }
2109
2110 rtx
2111 default_load_returned_bounds (rtx slot ATTRIBUTE_UNUSED)
2112 {
2113   gcc_unreachable ();
2114 }
2115
2116 void
2117 default_store_returned_bounds (rtx slot ATTRIBUTE_UNUSED,
2118                                rtx bounds ATTRIBUTE_UNUSED)
2119 {
2120   gcc_unreachable ();
2121 }
2122
2123 /* Default version of canonicalize_comparison.  */
2124
2125 void
2126 default_canonicalize_comparison (int *, rtx *, rtx *, bool)
2127 {
2128 }
2129
2130 /* Default implementation of TARGET_ATOMIC_ASSIGN_EXPAND_FENV.  */
2131
2132 void
2133 default_atomic_assign_expand_fenv (tree *, tree *, tree *)
2134 {
2135 }
2136
2137 #ifndef PAD_VARARGS_DOWN
2138 #define PAD_VARARGS_DOWN BYTES_BIG_ENDIAN
2139 #endif
2140
2141 /* Build an indirect-ref expression over the given TREE, which represents a
2142    piece of a va_arg() expansion.  */
2143 tree
2144 build_va_arg_indirect_ref (tree addr)
2145 {
2146   addr = build_simple_mem_ref_loc (EXPR_LOCATION (addr), addr);
2147   return addr;
2148 }
2149
2150 /* The "standard" implementation of va_arg: read the value from the
2151    current (padded) address and increment by the (padded) size.  */
2152
2153 tree
2154 std_gimplify_va_arg_expr (tree valist, tree type, gimple_seq *pre_p,
2155                           gimple_seq *post_p)
2156 {
2157   tree addr, t, type_size, rounded_size, valist_tmp;
2158   unsigned HOST_WIDE_INT align, boundary;
2159   bool indirect;
2160
2161   /* All of the alignment and movement below is for args-grow-up machines.
2162      As of 2004, there are only 3 ARGS_GROW_DOWNWARD targets, and they all
2163      implement their own specialized gimplify_va_arg_expr routines.  */
2164   if (ARGS_GROW_DOWNWARD)
2165     gcc_unreachable ();
2166
2167   indirect = pass_by_reference (NULL, TYPE_MODE (type), type, false);
2168   if (indirect)
2169     type = build_pointer_type (type);
2170
2171   if (targetm.calls.split_complex_arg
2172       && TREE_CODE (type) == COMPLEX_TYPE
2173       && targetm.calls.split_complex_arg (type))
2174     {
2175       tree real_part, imag_part;
2176
2177       real_part = std_gimplify_va_arg_expr (valist,
2178                                             TREE_TYPE (type), pre_p, NULL);
2179       real_part = get_initialized_tmp_var (real_part, pre_p, NULL);
2180
2181       imag_part = std_gimplify_va_arg_expr (unshare_expr (valist),
2182                                             TREE_TYPE (type), pre_p, NULL);
2183       imag_part = get_initialized_tmp_var (imag_part, pre_p, NULL);
2184
2185       return build2 (COMPLEX_EXPR, type, real_part, imag_part);
2186    }
2187
2188   align = PARM_BOUNDARY / BITS_PER_UNIT;
2189   boundary = targetm.calls.function_arg_boundary (TYPE_MODE (type), type);
2190
2191   /* When we align parameter on stack for caller, if the parameter
2192      alignment is beyond MAX_SUPPORTED_STACK_ALIGNMENT, it will be
2193      aligned at MAX_SUPPORTED_STACK_ALIGNMENT.  We will match callee
2194      here with caller.  */
2195   if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
2196     boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
2197
2198   boundary /= BITS_PER_UNIT;
2199
2200   /* Hoist the valist value into a temporary for the moment.  */
2201   valist_tmp = get_initialized_tmp_var (valist, pre_p, NULL);
2202
2203   /* va_list pointer is aligned to PARM_BOUNDARY.  If argument actually
2204      requires greater alignment, we must perform dynamic alignment.  */
2205   if (boundary > align
2206       && !TYPE_EMPTY_P (type)
2207       && !integer_zerop (TYPE_SIZE (type)))
2208     {
2209       t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist_tmp,
2210                   fold_build_pointer_plus_hwi (valist_tmp, boundary - 1));
2211       gimplify_and_add (t, pre_p);
2212
2213       t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist_tmp,
2214                   fold_build2 (BIT_AND_EXPR, TREE_TYPE (valist),
2215                                valist_tmp,
2216                                build_int_cst (TREE_TYPE (valist), -boundary)));
2217       gimplify_and_add (t, pre_p);
2218     }
2219   else
2220     boundary = align;
2221
2222   /* If the actual alignment is less than the alignment of the type,
2223      adjust the type accordingly so that we don't assume strict alignment
2224      when dereferencing the pointer.  */
2225   boundary *= BITS_PER_UNIT;
2226   if (boundary < TYPE_ALIGN (type))
2227     {
2228       type = build_variant_type_copy (type);
2229       SET_TYPE_ALIGN (type, boundary);
2230     }
2231
2232   /* Compute the rounded size of the type.  */
2233   type_size = arg_size_in_bytes (type);
2234   rounded_size = round_up (type_size, align);
2235
2236   /* Reduce rounded_size so it's sharable with the postqueue.  */
2237   gimplify_expr (&rounded_size, pre_p, post_p, is_gimple_val, fb_rvalue);
2238
2239   /* Get AP.  */
2240   addr = valist_tmp;
2241   if (PAD_VARARGS_DOWN && !integer_zerop (rounded_size))
2242     {
2243       /* Small args are padded downward.  */
2244       t = fold_build2_loc (input_location, GT_EXPR, sizetype,
2245                        rounded_size, size_int (align));
2246       t = fold_build3 (COND_EXPR, sizetype, t, size_zero_node,
2247                        size_binop (MINUS_EXPR, rounded_size, type_size));
2248       addr = fold_build_pointer_plus (addr, t);
2249     }
2250
2251   /* Compute new value for AP.  */
2252   t = fold_build_pointer_plus (valist_tmp, rounded_size);
2253   t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist, t);
2254   gimplify_and_add (t, pre_p);
2255
2256   addr = fold_convert (build_pointer_type (type), addr);
2257
2258   if (indirect)
2259     addr = build_va_arg_indirect_ref (addr);
2260
2261   return build_va_arg_indirect_ref (addr);
2262 }
2263
2264 void
2265 default_setup_incoming_vararg_bounds (cumulative_args_t ca ATTRIBUTE_UNUSED,
2266                                       machine_mode mode ATTRIBUTE_UNUSED,
2267                                       tree type ATTRIBUTE_UNUSED,
2268                                       int *pretend_arg_size ATTRIBUTE_UNUSED,
2269                                       int second_time ATTRIBUTE_UNUSED)
2270 {
2271 }
2272
2273 /* An implementation of TARGET_CAN_USE_DOLOOP_P for targets that do
2274    not support nested low-overhead loops.  */
2275
2276 bool
2277 can_use_doloop_if_innermost (const widest_int &, const widest_int &,
2278                              unsigned int loop_depth, bool)
2279 {
2280   return loop_depth == 1;
2281 }
2282
2283 /* Default implementation of TARGET_OPTAB_SUPPORTED_P.  */
2284
2285 bool
2286 default_optab_supported_p (int, machine_mode, machine_mode, optimization_type)
2287 {
2288   return true;
2289 }
2290
2291 /* Default implementation of TARGET_MAX_NOCE_IFCVT_SEQ_COST.  */
2292
2293 unsigned int
2294 default_max_noce_ifcvt_seq_cost (edge e)
2295 {
2296   bool predictable_p = predictable_edge_p (e);
2297
2298   enum compiler_param param
2299     = (predictable_p
2300        ? PARAM_MAX_RTL_IF_CONVERSION_PREDICTABLE_COST
2301        : PARAM_MAX_RTL_IF_CONVERSION_UNPREDICTABLE_COST);
2302
2303   /* If we have a parameter set, use that, otherwise take a guess using
2304      BRANCH_COST.  */
2305   if (global_options_set.x_param_values[param])
2306     return PARAM_VALUE (param);
2307   else
2308     return BRANCH_COST (true, predictable_p) * COSTS_N_INSNS (3);
2309 }
2310
2311 /* Default implementation of TARGET_MIN_ARITHMETIC_PRECISION.  */
2312
2313 unsigned int
2314 default_min_arithmetic_precision (void)
2315 {
2316   return WORD_REGISTER_OPERATIONS ? BITS_PER_WORD : BITS_PER_UNIT;
2317 }
2318
2319 /* Default implementation of TARGET_C_EXCESS_PRECISION.  */
2320
2321 enum flt_eval_method
2322 default_excess_precision (enum excess_precision_type ATTRIBUTE_UNUSED)
2323 {
2324   return FLT_EVAL_METHOD_PROMOTE_TO_FLOAT;
2325 }
2326
2327 /* Default implementation for
2328   TARGET_STACK_CLASH_PROTECTION_ALLOCA_PROBE_RANGE.  */
2329 HOST_WIDE_INT
2330 default_stack_clash_protection_alloca_probe_range (void)
2331 {
2332   return 0;
2333 }
2334
2335 /* The default implementation of TARGET_EARLY_REMAT_MODES.  */
2336
2337 void
2338 default_select_early_remat_modes (sbitmap)
2339 {
2340 }
2341
2342 /* The default implementation of TARGET_PREFERRED_ELSE_VALUE.  */
2343
2344 tree
2345 default_preferred_else_value (unsigned, tree type, unsigned, tree *)
2346 {
2347   return build_zero_cst (type);
2348 }
2349
2350 /* Default implementation of TARGET_HAVE_SPECULATION_SAFE_VALUE.  */
2351 bool
2352 default_have_speculation_safe_value (bool active ATTRIBUTE_UNUSED)
2353 {
2354 #ifdef HAVE_speculation_barrier
2355   return active ? HAVE_speculation_barrier : true;
2356 #else
2357   return false;
2358 #endif
2359 }
2360 /* Alternative implementation of TARGET_HAVE_SPECULATION_SAFE_VALUE
2361    that can be used on targets that never have speculative execution.  */
2362 bool
2363 speculation_safe_value_not_needed (bool active)
2364 {
2365   return !active;
2366 }
2367
2368 /* Default implementation of the speculation-safe-load builtin.  This
2369    implementation simply copies val to result and generates a
2370    speculation_barrier insn, if such a pattern is defined.  */
2371 rtx
2372 default_speculation_safe_value (machine_mode mode ATTRIBUTE_UNUSED,
2373                                 rtx result, rtx val,
2374                                 rtx failval ATTRIBUTE_UNUSED)
2375 {
2376   emit_move_insn (result, val);
2377
2378 #ifdef HAVE_speculation_barrier
2379   /* Assume the target knows what it is doing: if it defines a
2380      speculation barrier, but it is not enabled, then assume that one
2381      isn't needed.  */
2382   if (HAVE_speculation_barrier)
2383     emit_insn (gen_speculation_barrier ());
2384 #endif
2385
2386   return result;
2387 }
2388
2389 void
2390 default_remove_extra_call_preserved_regs (rtx_insn *, HARD_REG_SET *)
2391 {
2392 }
2393
2394 #include "gt-targhooks.h"