gcc/targhooks.c

   1 /* Default target hook functions.
   2    Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
   3    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 3, 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 COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 /* The migration of target macros to target hooks works as follows:
  22
  23    1. Create a target hook that uses the existing target macros to
  24       implement the same functionality.
  25
  26    2. Convert all the MI files to use the hook instead of the macro.
  27
  28    3. Repeat for a majority of the remaining target macros.  This will
  29       take some time.
  30
  31    4. Tell target maintainers to start migrating.
  32
  33    5. Eventually convert the backends to override the hook instead of
  34       defining the macros.  This will take some time too.
  35
  36    6. TBD when, poison the macros.  Unmigrated targets will break at
  37       this point.
  38
  39    Note that we expect steps 1-3 to be done by the people that
  40    understand what the MI does with each macro, and step 5 to be done
  41    by the target maintainers for their respective targets.
  42
  43    Note that steps 1 and 2 don't have to be done together, but no
  44    target can override the new hook until step 2 is complete for it.
  45
  46    Once the macros are poisoned, we will revert to the old migration
  47    rules - migrate the macro, callers, and targets all at once.  This
  48    comment can thus be removed at that point.  */
  49
  50 #include "config.h"
  51 #include "system.h"
  52 #include "coretypes.h"
  53 #include "tm.h"
  54 #include "machmode.h"
  55 #include "rtl.h"
  56 #include "tree.h"
  57 #include "expr.h"
  58 #include "output.h"
  59 #include "diagnostic-core.h"
  60 #include "function.h"
  61 #include "target.h"
  62 #include "tm_p.h"
  63 #include "target-def.h"
  64 #include "ggc.h"
  65 #include "hard-reg-set.h"
  66 #include "regs.h"
  67 #include "reload.h"
  68 #include "optabs.h"
  69 #include "recog.h"
  70 #include "intl.h"
  71 #include "opts.h"
  72 #include "tree-flow.h"
  73 #include "tree-ssa-alias.h"
  74
  75
  76 bool
  77 default_legitimate_address_p (enum machine_mode mode ATTRIBUTE_UNUSED,
  78                               rtx addr ATTRIBUTE_UNUSED,
  79                               bool strict ATTRIBUTE_UNUSED)
  80 {
  81 #ifdef GO_IF_LEGITIMATE_ADDRESS
  82   /* Defer to the old implementation using a goto.  */
  83   if (strict)
  84     return strict_memory_address_p (mode, addr);
  85   else
  86     return memory_address_p (mode, addr);
  87 #else
  88   gcc_unreachable ();
  89 #endif
  90 }
  91
  92 void
  93 default_external_libcall (rtx fun ATTRIBUTE_UNUSED)
  94 {
  95 #ifdef ASM_OUTPUT_EXTERNAL_LIBCALL
  96   ASM_OUTPUT_EXTERNAL_LIBCALL(asm_out_file, fun);
  97 #endif
  98 }
  99
 100 int
 101 default_unspec_may_trap_p (const_rtx x, unsigned flags)
 102 {
 103   int i;
 104
 105   if (GET_CODE (x) == UNSPEC_VOLATILE
 106       /* Any floating arithmetic may trap.  */
 107       || (SCALAR_FLOAT_MODE_P (GET_MODE (x))
 108           && flag_trapping_math))
 109     return 1;
 110
 111   for (i = 0; i < XVECLEN (x, 0); ++i)
 112     {
 113       if (may_trap_p_1 (XVECEXP (x, 0, i), flags))
 114         return 1;
 115     }
 116
 117   return 0;
 118 }
 119
 120 enum machine_mode
 121 default_promote_function_mode (const_tree type ATTRIBUTE_UNUSED,
 122                                enum machine_mode mode,
 123                                int *punsignedp ATTRIBUTE_UNUSED,
 124                                const_tree funtype ATTRIBUTE_UNUSED,
 125                                int for_return ATTRIBUTE_UNUSED)
 126 {
 127   if (type != NULL_TREE && for_return == 2)
 128     return promote_mode (type, mode, punsignedp);
 129   return mode;
 130 }
 131
 132 enum machine_mode
 133 default_promote_function_mode_always_promote (const_tree type,
 134                                               enum machine_mode mode,
 135                                               int *punsignedp,
 136                                               const_tree funtype ATTRIBUTE_UNUSED,
 137                                               int for_return ATTRIBUTE_UNUSED)
 138 {
 139   return promote_mode (type, mode, punsignedp);
 140 }
 141
 142
 143 enum machine_mode
 144 default_cc_modes_compatible (enum machine_mode m1, enum machine_mode m2)
 145 {
 146   if (m1 == m2)
 147     return m1;
 148   return VOIDmode;
 149 }
 150
 151 bool
 152 default_return_in_memory (const_tree type,
 153                           const_tree fntype ATTRIBUTE_UNUSED)
 154 {
 155   return (TYPE_MODE (type) == BLKmode);
 156 }
 157
 158 rtx
 159 default_legitimize_address (rtx x, rtx orig_x ATTRIBUTE_UNUSED,
 160                             enum machine_mode mode ATTRIBUTE_UNUSED)
 161 {
 162   return x;
 163 }
 164
 165 rtx
 166 default_expand_builtin_saveregs (void)
 167 {
 168   error ("__builtin_saveregs not supported by this target");
 169   return const0_rtx;
 170 }
 171
 172 void
 173 default_setup_incoming_varargs (cumulative_args_t ca ATTRIBUTE_UNUSED,
 174                                 enum machine_mode mode ATTRIBUTE_UNUSED,
 175                                 tree type ATTRIBUTE_UNUSED,
 176                                 int *pretend_arg_size ATTRIBUTE_UNUSED,
 177                                 int second_time ATTRIBUTE_UNUSED)
 178 {
 179 }
 180
 181 /* The default implementation of TARGET_BUILTIN_SETJMP_FRAME_VALUE.  */
 182
 183 rtx
 184 default_builtin_setjmp_frame_value (void)
 185 {
 186   return virtual_stack_vars_rtx;
 187 }
 188
 189 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns false.  */
 190
 191 bool
 192 hook_bool_CUMULATIVE_ARGS_false (cumulative_args_t ca ATTRIBUTE_UNUSED)
 193 {
 194   return false;
 195 }
 196
 197 bool
 198 default_pretend_outgoing_varargs_named (cumulative_args_t ca ATTRIBUTE_UNUSED)
 199 {
 200   return (targetm.calls.setup_incoming_varargs
 201           != default_setup_incoming_varargs);
 202 }
 203
 204 enum machine_mode
 205 default_eh_return_filter_mode (void)
 206 {
 207   return targetm.unwind_word_mode ();
 208 }
 209
 210 enum machine_mode
 211 default_libgcc_cmp_return_mode (void)
 212 {
 213   return word_mode;
 214 }
 215
 216 enum machine_mode
 217 default_libgcc_shift_count_mode (void)
 218 {
 219   return word_mode;
 220 }
 221
 222 enum machine_mode
 223 default_unwind_word_mode (void)
 224 {
 225   return word_mode;
 226 }
 227
 228 /* The default implementation of TARGET_SHIFT_TRUNCATION_MASK.  */
 229
 230 unsigned HOST_WIDE_INT
 231 default_shift_truncation_mask (enum machine_mode mode)
 232 {
 233   return SHIFT_COUNT_TRUNCATED ? GET_MODE_BITSIZE (mode) - 1 : 0;
 234 }
 235
 236 /* The default implementation of TARGET_MIN_DIVISIONS_FOR_RECIP_MUL.  */
 237
 238 unsigned int
 239 default_min_divisions_for_recip_mul (enum machine_mode mode ATTRIBUTE_UNUSED)
 240 {
 241   return have_insn_for (DIV, mode) ? 3 : 2;
 242 }
 243
 244 /* The default implementation of TARGET_MODE_REP_EXTENDED.  */
 245
 246 int
 247 default_mode_rep_extended (enum machine_mode mode ATTRIBUTE_UNUSED,
 248                            enum machine_mode mode_rep ATTRIBUTE_UNUSED)
 249 {
 250   return UNKNOWN;
 251 }
 252
 253 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns true.  */
 254
 255 bool
 256 hook_bool_CUMULATIVE_ARGS_true (cumulative_args_t a ATTRIBUTE_UNUSED)
 257 {
 258   return true;
 259 }
 260
 261 /* Return machine mode for non-standard suffix
 262    or VOIDmode if non-standard suffixes are unsupported.  */
 263 enum machine_mode
 264 default_mode_for_suffix (char suffix ATTRIBUTE_UNUSED)
 265 {
 266   return VOIDmode;
 267 }
 268
 269 /* The generic C++ ABI specifies this is a 64-bit value.  */
 270 tree
 271 default_cxx_guard_type (void)
 272 {
 273   return long_long_integer_type_node;
 274 }
 275
 276
 277 /* Returns the size of the cookie to use when allocating an array
 278    whose elements have the indicated TYPE.  Assumes that it is already
 279    known that a cookie is needed.  */
 280
 281 tree
 282 default_cxx_get_cookie_size (tree type)
 283 {
 284   tree cookie_size;
 285
 286   /* We need to allocate an additional max (sizeof (size_t), alignof
 287      (true_type)) bytes.  */
 288   tree sizetype_size;
 289   tree type_align;
 290
 291   sizetype_size = size_in_bytes (sizetype);
 292   type_align = size_int (TYPE_ALIGN_UNIT (type));
 293   if (INT_CST_LT_UNSIGNED (type_align, sizetype_size))
 294     cookie_size = sizetype_size;
 295   else
 296     cookie_size = type_align;
 297
 298   return cookie_size;
 299 }
 300
 301 /* Return true if a parameter must be passed by reference.  This version
 302    of the TARGET_PASS_BY_REFERENCE hook uses just MUST_PASS_IN_STACK.  */
 303
 304 bool
 305 hook_pass_by_reference_must_pass_in_stack (cumulative_args_t c ATTRIBUTE_UNUSED,
 306         enum machine_mode mode ATTRIBUTE_UNUSED, const_tree type ATTRIBUTE_UNUSED,
 307         bool named_arg ATTRIBUTE_UNUSED)
 308 {
 309   return targetm.calls.must_pass_in_stack (mode, type);
 310 }
 311
 312 /* Return true if a parameter follows callee copies conventions.  This
 313    version of the hook is true for all named arguments.  */
 314
 315 bool
 316 hook_callee_copies_named (cumulative_args_t ca ATTRIBUTE_UNUSED,
 317                           enum machine_mode mode ATTRIBUTE_UNUSED,
 318                           const_tree type ATTRIBUTE_UNUSED, bool named)
 319 {
 320   return named;
 321 }
 322
 323 /* Emit to STREAM the assembler syntax for insn operand X.  */
 324
 325 void
 326 default_print_operand (FILE *stream ATTRIBUTE_UNUSED, rtx x ATTRIBUTE_UNUSED,
 327                        int code ATTRIBUTE_UNUSED)
 328 {
 329 #ifdef PRINT_OPERAND
 330   PRINT_OPERAND (stream, x, code);
 331 #else
 332   gcc_unreachable ();
 333 #endif
 334 }
 335
 336 /* Emit to STREAM the assembler syntax for an insn operand whose memory
 337    address is X.  */
 338
 339 void
 340 default_print_operand_address (FILE *stream ATTRIBUTE_UNUSED,
 341                                rtx x ATTRIBUTE_UNUSED)
 342 {
 343 #ifdef PRINT_OPERAND_ADDRESS
 344   PRINT_OPERAND_ADDRESS (stream, x);
 345 #else
 346   gcc_unreachable ();
 347 #endif
 348 }
 349
 350 /* Return true if CODE is a valid punctuation character for the
 351    `print_operand' hook.  */
 352
 353 bool
 354 default_print_operand_punct_valid_p (unsigned char code ATTRIBUTE_UNUSED)
 355 {
 356 #ifdef PRINT_OPERAND_PUNCT_VALID_P
 357   return PRINT_OPERAND_PUNCT_VALID_P (code);
 358 #else
 359   return false;
 360 #endif
 361 }
 362
 363 /* The default implementation of TARGET_MANGLE_ASSEMBLER_NAME.  */
 364 tree
 365 default_mangle_assembler_name (const char *name ATTRIBUTE_UNUSED)
 366 {
 367   const char *skipped = name + (*name == '*' ? 1 : 0);
 368   const char *stripped = targetm.strip_name_encoding (skipped);
 369   if (*name != '*' && user_label_prefix[0])
 370     stripped = ACONCAT ((user_label_prefix, stripped, NULL));
 371   return get_identifier (stripped);
 372 }
 373
 374 /* True if MODE is valid for the target.  By "valid", we mean able to
 375    be manipulated in non-trivial ways.  In particular, this means all
 376    the arithmetic is supported.
 377
 378    By default we guess this means that any C type is supported.  If
 379    we can't map the mode back to a type that would be available in C,
 380    then reject it.  Special case, here, is the double-word arithmetic
 381    supported by optabs.c.  */
 382
 383 bool
 384 default_scalar_mode_supported_p (enum machine_mode mode)
 385 {
 386   int precision = GET_MODE_PRECISION (mode);
 387
 388   switch (GET_MODE_CLASS (mode))
 389     {
 390     case MODE_PARTIAL_INT:
 391     case MODE_INT:
 392       if (precision == CHAR_TYPE_SIZE)
 393         return true;
 394       if (precision == SHORT_TYPE_SIZE)
 395         return true;
 396       if (precision == INT_TYPE_SIZE)
 397         return true;
 398       if (precision == LONG_TYPE_SIZE)
 399         return true;
 400       if (precision == LONG_LONG_TYPE_SIZE)
 401         return true;
 402       if (precision == 2 * BITS_PER_WORD)
 403         return true;
 404       return false;
 405
 406     case MODE_FLOAT:
 407       if (precision == FLOAT_TYPE_SIZE)
 408         return true;
 409       if (precision == DOUBLE_TYPE_SIZE)
 410         return true;
 411       if (precision == LONG_DOUBLE_TYPE_SIZE)
 412         return true;
 413       return false;
 414
 415     case MODE_DECIMAL_FLOAT:
 416     case MODE_FRACT:
 417     case MODE_UFRACT:
 418     case MODE_ACCUM:
 419     case MODE_UACCUM:
 420       return false;
 421
 422     default:
 423       gcc_unreachable ();
 424     }
 425 }
 426
 427 /* Make some target macros useable by target-independent code.  */
 428 bool
 429 targhook_words_big_endian (void)
 430 {
 431   return !!WORDS_BIG_ENDIAN;
 432 }
 433
 434 bool
 435 targhook_float_words_big_endian (void)
 436 {
 437   return !!FLOAT_WORDS_BIG_ENDIAN;
 438 }
 439
 440 /* True if the target supports decimal floating point.  */
 441
 442 bool
 443 default_decimal_float_supported_p (void)
 444 {
 445   return ENABLE_DECIMAL_FLOAT;
 446 }
 447
 448 /* True if the target supports fixed-point arithmetic.  */
 449
 450 bool
 451 default_fixed_point_supported_p (void)
 452 {
 453   return ENABLE_FIXED_POINT;
 454 }
 455
 456 /* NULL if INSN insn is valid within a low-overhead loop, otherwise returns
 457    an error message.
 458
 459    This function checks whether a given INSN is valid within a low-overhead
 460    loop.  If INSN is invalid it returns the reason for that, otherwise it
 461    returns NULL. A called function may clobber any special registers required
 462    for low-overhead looping. Additionally, some targets (eg, PPC) use the count
 463    register for branch on table instructions. We reject the doloop pattern in
 464    these cases.  */
 465
 466 const char *
 467 default_invalid_within_doloop (const_rtx insn)
 468 {
 469   if (CALL_P (insn))
 470     return "Function call in loop.";
 471
 472   if (JUMP_TABLE_DATA_P (insn))
 473     return "Computed branch in the loop.";
 474
 475   return NULL;
 476 }
 477
 478 /* Mapping of builtin functions to vectorized variants.  */
 479
 480 tree
 481 default_builtin_vectorized_function (tree fndecl ATTRIBUTE_UNUSED,
 482                                      tree type_out ATTRIBUTE_UNUSED,
 483                                      tree type_in ATTRIBUTE_UNUSED)
 484 {
 485   return NULL_TREE;
 486 }
 487
 488 /* Vectorized conversion.  */
 489
 490 tree
 491 default_builtin_vectorized_conversion (unsigned int code ATTRIBUTE_UNUSED,
 492                                        tree dest_type ATTRIBUTE_UNUSED,
 493                                        tree src_type ATTRIBUTE_UNUSED)
 494 {
 495   return NULL_TREE;
 496 }
 497
 498 /* Default vectorizer cost model values.  */
 499
 500 int
 501 default_builtin_vectorization_cost (enum vect_cost_for_stmt type_of_cost,
 502                                     tree vectype ATTRIBUTE_UNUSED,
 503                                     int misalign ATTRIBUTE_UNUSED)
 504 {
 505   switch (type_of_cost)
 506     {
 507       case scalar_stmt:
 508       case scalar_load:
 509       case scalar_store:
 510       case vector_stmt:
 511       case vector_load:
 512       case vector_store:
 513       case vec_to_scalar:
 514       case scalar_to_vec:
 515       case cond_branch_not_taken:
 516       case vec_perm:
 517       case vec_promote_demote:
 518         return 1;
 519
 520       case unaligned_load:
 521       case unaligned_store:
 522         return 2;
 523
 524       case cond_branch_taken:
 525         return 3;
 526
 527       default:
 528         gcc_unreachable ();
 529     }
 530 }
 531
 532 /* Reciprocal.  */
 533
 534 tree
 535 default_builtin_reciprocal (unsigned int fn ATTRIBUTE_UNUSED,
 536                             bool md_fn ATTRIBUTE_UNUSED,
 537                             bool sqrt ATTRIBUTE_UNUSED)
 538 {
 539   return NULL_TREE;
 540 }
 541
 542 bool
 543 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false (
 544         cumulative_args_t ca ATTRIBUTE_UNUSED,
 545         enum machine_mode mode ATTRIBUTE_UNUSED,
 546         const_tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
 547 {
 548   return false;
 549 }
 550
 551 bool
 552 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_true (
 553         cumulative_args_t ca ATTRIBUTE_UNUSED,
 554         enum machine_mode mode ATTRIBUTE_UNUSED,
 555         const_tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
 556 {
 557   return true;
 558 }
 559
 560 int
 561 hook_int_CUMULATIVE_ARGS_mode_tree_bool_0 (
 562         cumulative_args_t ca ATTRIBUTE_UNUSED,
 563         enum machine_mode mode ATTRIBUTE_UNUSED,
 564         tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
 565 {
 566   return 0;
 567 }
 568
 569 void
 570 default_function_arg_advance (cumulative_args_t ca ATTRIBUTE_UNUSED,
 571                               enum machine_mode mode ATTRIBUTE_UNUSED,
 572                               const_tree type ATTRIBUTE_UNUSED,
 573                               bool named ATTRIBUTE_UNUSED)
 574 {
 575   gcc_unreachable ();
 576 }
 577
 578 rtx
 579 default_function_arg (cumulative_args_t ca ATTRIBUTE_UNUSED,
 580                       enum machine_mode mode ATTRIBUTE_UNUSED,
 581                       const_tree type ATTRIBUTE_UNUSED,
 582                       bool named ATTRIBUTE_UNUSED)
 583 {
 584   gcc_unreachable ();
 585 }
 586
 587 rtx
 588 default_function_incoming_arg (cumulative_args_t ca ATTRIBUTE_UNUSED,
 589                                enum machine_mode mode ATTRIBUTE_UNUSED,
 590                                const_tree type ATTRIBUTE_UNUSED,
 591                                bool named ATTRIBUTE_UNUSED)
 592 {
 593   gcc_unreachable ();
 594 }
 595
 596 unsigned int
 597 default_function_arg_boundary (enum machine_mode mode ATTRIBUTE_UNUSED,
 598                                const_tree type ATTRIBUTE_UNUSED)
 599 {
 600   return PARM_BOUNDARY;
 601 }
 602
 603 unsigned int
 604 default_function_arg_round_boundary (enum machine_mode mode ATTRIBUTE_UNUSED,
 605                                      const_tree type ATTRIBUTE_UNUSED)
 606 {
 607   return PARM_BOUNDARY;
 608 }
 609
 610 void
 611 hook_void_bitmap (bitmap regs ATTRIBUTE_UNUSED)
 612 {
 613 }
 614
 615 const char *
 616 hook_invalid_arg_for_unprototyped_fn (
 617         const_tree typelist ATTRIBUTE_UNUSED,
 618         const_tree funcdecl ATTRIBUTE_UNUSED,
 619         const_tree val ATTRIBUTE_UNUSED)
 620 {
 621   return NULL;
 622 }
 623
 624 /* Initialize the stack protection decls.  */
 625
 626 /* Stack protection related decls living in libgcc.  */
 627 static GTY(()) tree stack_chk_guard_decl;
 628
 629 tree
 630 default_stack_protect_guard (void)
 631 {
 632   tree t = stack_chk_guard_decl;
 633
 634   if (t == NULL)
 635     {
 636       rtx x;
 637
 638       t = build_decl (UNKNOWN_LOCATION,
 639                       VAR_DECL, get_identifier ("__stack_chk_guard"),
 640                       ptr_type_node);
 641       TREE_STATIC (t) = 1;
 642       TREE_PUBLIC (t) = 1;
 643       DECL_EXTERNAL (t) = 1;
 644       TREE_USED (t) = 1;
 645       TREE_THIS_VOLATILE (t) = 1;
 646       DECL_ARTIFICIAL (t) = 1;
 647       DECL_IGNORED_P (t) = 1;
 648
 649       /* Do not share RTL as the declaration is visible outside of
 650          current function.  */
 651       x = DECL_RTL (t);
 652       RTX_FLAG (x, used) = 1;
 653
 654       stack_chk_guard_decl = t;
 655     }
 656
 657   return t;
 658 }
 659
 660 static GTY(()) tree stack_chk_fail_decl;
 661
 662 tree
 663 default_external_stack_protect_fail (void)
 664 {
 665   tree t = stack_chk_fail_decl;
 666
 667   if (t == NULL_TREE)
 668     {
 669       t = build_function_type_list (void_type_node, NULL_TREE);
 670       t = build_decl (UNKNOWN_LOCATION,
 671                       FUNCTION_DECL, get_identifier ("__stack_chk_fail"), t);
 672       TREE_STATIC (t) = 1;
 673       TREE_PUBLIC (t) = 1;
 674       DECL_EXTERNAL (t) = 1;
 675       TREE_USED (t) = 1;
 676       TREE_THIS_VOLATILE (t) = 1;
 677       TREE_NOTHROW (t) = 1;
 678       DECL_ARTIFICIAL (t) = 1;
 679       DECL_IGNORED_P (t) = 1;
 680       DECL_VISIBILITY (t) = VISIBILITY_DEFAULT;
 681       DECL_VISIBILITY_SPECIFIED (t) = 1;
 682
 683       stack_chk_fail_decl = t;
 684     }
 685
 686   return build_call_expr (t, 0);
 687 }
 688
 689 tree
 690 default_hidden_stack_protect_fail (void)
 691 {
 692 #ifndef HAVE_GAS_HIDDEN
 693   return default_external_stack_protect_fail ();
 694 #else
 695   tree t = stack_chk_fail_decl;
 696
 697   if (!flag_pic)
 698     return default_external_stack_protect_fail ();
 699
 700   if (t == NULL_TREE)
 701     {
 702       t = build_function_type_list (void_type_node, NULL_TREE);
 703       t = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL,
 704                       get_identifier ("__stack_chk_fail_local"), t);
 705       TREE_STATIC (t) = 1;
 706       TREE_PUBLIC (t) = 1;
 707       DECL_EXTERNAL (t) = 1;
 708       TREE_USED (t) = 1;
 709       TREE_THIS_VOLATILE (t) = 1;
 710       TREE_NOTHROW (t) = 1;
 711       DECL_ARTIFICIAL (t) = 1;
 712       DECL_IGNORED_P (t) = 1;
 713       DECL_VISIBILITY_SPECIFIED (t) = 1;
 714       DECL_VISIBILITY (t) = VISIBILITY_HIDDEN;
 715
 716       stack_chk_fail_decl = t;
 717     }
 718
 719   return build_call_expr (t, 0);
 720 #endif
 721 }
 722
 723 bool
 724 hook_bool_const_rtx_commutative_p (const_rtx x,
 725                                    int outer_code ATTRIBUTE_UNUSED)
 726 {
 727   return COMMUTATIVE_P (x);
 728 }
 729
 730 rtx
 731 default_function_value (const_tree ret_type ATTRIBUTE_UNUSED,
 732                         const_tree fn_decl_or_type,
 733                         bool outgoing ATTRIBUTE_UNUSED)
 734 {
 735   /* The old interface doesn't handle receiving the function type.  */
 736   if (fn_decl_or_type
 737       && !DECL_P (fn_decl_or_type))
 738     fn_decl_or_type = NULL;
 739
 740 #ifdef FUNCTION_VALUE
 741   return FUNCTION_VALUE (ret_type, fn_decl_or_type);
 742 #else
 743   gcc_unreachable ();
 744 #endif
 745 }
 746
 747 rtx
 748 default_libcall_value (enum machine_mode mode ATTRIBUTE_UNUSED,
 749                        const_rtx fun ATTRIBUTE_UNUSED)
 750 {
 751 #ifdef LIBCALL_VALUE
 752   return LIBCALL_VALUE (mode);
 753 #else
 754   gcc_unreachable ();
 755 #endif
 756 }
 757
 758 /* The default hook for TARGET_FUNCTION_VALUE_REGNO_P.  */
 759
 760 bool
 761 default_function_value_regno_p (const unsigned int regno ATTRIBUTE_UNUSED)
 762 {
 763 #ifdef FUNCTION_VALUE_REGNO_P
 764   return FUNCTION_VALUE_REGNO_P (regno);
 765 #else
 766   gcc_unreachable ();
 767 #endif
 768 }
 769
 770 rtx
 771 default_internal_arg_pointer (void)
 772 {
 773   /* If the reg that the virtual arg pointer will be translated into is
 774      not a fixed reg or is the stack pointer, make a copy of the virtual
 775      arg pointer, and address parms via the copy.  The frame pointer is
 776      considered fixed even though it is not marked as such.  */
 777   if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
 778        || ! (fixed_regs[ARG_POINTER_REGNUM]
 779              || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
 780     return copy_to_reg (virtual_incoming_args_rtx);
 781   else
 782     return virtual_incoming_args_rtx;
 783 }
 784
 785 rtx
 786 default_static_chain (const_tree fndecl, bool incoming_p)
 787 {
 788   if (!DECL_STATIC_CHAIN (fndecl))
 789     return NULL;
 790
 791   if (incoming_p)
 792     {
 793 #ifdef STATIC_CHAIN_INCOMING_REGNUM
 794       return gen_rtx_REG (Pmode, STATIC_CHAIN_INCOMING_REGNUM);
 795 #endif
 796     }
 797
 798 #ifdef STATIC_CHAIN_REGNUM
 799   return gen_rtx_REG (Pmode, STATIC_CHAIN_REGNUM);
 800 #endif
 801
 802   {
 803     static bool issued_error;
 804     if (!issued_error)
 805       {
 806         issued_error = true;
 807         sorry ("nested functions not supported on this target");
 808       }
 809
 810     /* It really doesn't matter what we return here, so long at it
 811        doesn't cause the rest of the compiler to crash.  */
 812     return gen_rtx_MEM (Pmode, stack_pointer_rtx);
 813   }
 814 }
 815
 816 void
 817 default_trampoline_init (rtx ARG_UNUSED (m_tramp), tree ARG_UNUSED (t_func),
 818                          rtx ARG_UNUSED (r_chain))
 819 {
 820   sorry ("nested function trampolines not supported on this target");
 821 }
 822
 823 int
 824 default_return_pops_args (tree fundecl ATTRIBUTE_UNUSED,
 825                           tree funtype ATTRIBUTE_UNUSED,
 826                           int size ATTRIBUTE_UNUSED)
 827 {
 828   return 0;
 829 }
 830
 831 reg_class_t
 832 default_branch_target_register_class (void)
 833 {
 834   return NO_REGS;
 835 }
 836
 837 reg_class_t
 838 default_secondary_reload (bool in_p ATTRIBUTE_UNUSED, rtx x ATTRIBUTE_UNUSED,
 839                           reg_class_t reload_class_i ATTRIBUTE_UNUSED,
 840                           enum machine_mode reload_mode ATTRIBUTE_UNUSED,
 841                           secondary_reload_info *sri)
 842 {
 843   enum reg_class rclass = NO_REGS;
 844   enum reg_class reload_class = (enum reg_class) reload_class_i;
 845
 846   if (sri->prev_sri && sri->prev_sri->t_icode != CODE_FOR_nothing)
 847     {
 848       sri->icode = sri->prev_sri->t_icode;
 849       return NO_REGS;
 850     }
 851 #ifdef SECONDARY_INPUT_RELOAD_CLASS
 852   if (in_p)
 853     rclass = SECONDARY_INPUT_RELOAD_CLASS (reload_class, reload_mode, x);
 854 #endif
 855 #ifdef SECONDARY_OUTPUT_RELOAD_CLASS
 856   if (! in_p)
 857     rclass = SECONDARY_OUTPUT_RELOAD_CLASS (reload_class, reload_mode, x);
 858 #endif
 859   if (rclass != NO_REGS)
 860     {
 861       enum insn_code icode
 862         = direct_optab_handler (in_p ? reload_in_optab : reload_out_optab,
 863                                 reload_mode);
 864
 865       if (icode != CODE_FOR_nothing
 866           && !insn_operand_matches (icode, in_p, x))
 867         icode = CODE_FOR_nothing;
 868       else if (icode != CODE_FOR_nothing)
 869         {
 870           const char *insn_constraint, *scratch_constraint;
 871           char insn_letter, scratch_letter;
 872           enum reg_class insn_class, scratch_class;
 873
 874           gcc_assert (insn_data[(int) icode].n_operands == 3);
 875           insn_constraint = insn_data[(int) icode].operand[!in_p].constraint;
 876           if (!*insn_constraint)
 877             insn_class = ALL_REGS;
 878           else
 879             {
 880               if (in_p)
 881                 {
 882                   gcc_assert (*insn_constraint == '=');
 883                   insn_constraint++;
 884                 }
 885               insn_letter = *insn_constraint;
 886               insn_class
 887                 = (insn_letter == 'r' ? GENERAL_REGS
 888                    : REG_CLASS_FROM_CONSTRAINT ((unsigned char) insn_letter,
 889                                                 insn_constraint));
 890               gcc_assert (insn_class != NO_REGS);
 891             }
 892
 893           scratch_constraint = insn_data[(int) icode].operand[2].constraint;
 894           /* The scratch register's constraint must start with "=&",
 895              except for an input reload, where only "=" is necessary,
 896              and where it might be beneficial to re-use registers from
 897              the input.  */
 898           gcc_assert (scratch_constraint[0] == '='
 899                       && (in_p || scratch_constraint[1] == '&'));
 900           scratch_constraint++;
 901           if (*scratch_constraint == '&')
 902             scratch_constraint++;
 903           scratch_letter = *scratch_constraint;
 904           scratch_class
 905             = (scratch_letter == 'r' ? GENERAL_REGS
 906                : REG_CLASS_FROM_CONSTRAINT ((unsigned char) scratch_letter,
 907                                             scratch_constraint));
 908
 909           if (reg_class_subset_p (reload_class, insn_class))
 910             {
 911               gcc_assert (scratch_class == rclass);
 912               rclass = NO_REGS;
 913             }
 914           else
 915             rclass = insn_class;
 916
 917         }
 918       if (rclass == NO_REGS)
 919         sri->icode = icode;
 920       else
 921         sri->t_icode = icode;
 922     }
 923   return rclass;
 924 }
 925
 926 /* By default, if flag_pic is true, then neither local nor global relocs
 927    should be placed in readonly memory.  */
 928
 929 int
 930 default_reloc_rw_mask (void)
 931 {
 932   return flag_pic ? 3 : 0;
 933 }
 934
 935 /* By default, do no modification. */
 936 tree default_mangle_decl_assembler_name (tree decl ATTRIBUTE_UNUSED,
 937                                          tree id)
 938 {
 939    return id;
 940 }
 941
 942 bool
 943 default_builtin_vector_alignment_reachable (const_tree type, bool is_packed)
 944 {
 945   if (is_packed)
 946     return false;
 947
 948   /* Assuming that types whose size is > pointer-size are not guaranteed to be
 949      naturally aligned.  */
 950   if (tree_int_cst_compare (TYPE_SIZE (type), bitsize_int (POINTER_SIZE)) > 0)
 951     return false;
 952
 953   /* Assuming that types whose size is <= pointer-size
 954      are naturally aligned.  */
 955   return true;
 956 }
 957
 958 /* By default, assume that a target supports any factor of misalignment
 959    memory access if it supports movmisalign patten.
 960    is_packed is true if the memory access is defined in a packed struct.  */
 961 bool
 962 default_builtin_support_vector_misalignment (enum machine_mode mode,
 963                                              const_tree type
 964                                              ATTRIBUTE_UNUSED,
 965                                              int misalignment
 966                                              ATTRIBUTE_UNUSED,
 967                                              bool is_packed
 968                                              ATTRIBUTE_UNUSED)
 969 {
 970   if (optab_handler (movmisalign_optab, mode) != CODE_FOR_nothing)
 971     return true;
 972   return false;
 973 }
 974
 975 /* By default, only attempt to parallelize bitwise operations, and
 976    possibly adds/subtracts using bit-twiddling.  */
 977
 978 enum machine_mode
 979 default_preferred_simd_mode (enum machine_mode mode ATTRIBUTE_UNUSED)
 980 {
 981   return word_mode;
 982 }
 983
 984 /* By default only the size derived from the preferred vector mode
 985    is tried.  */
 986
 987 unsigned int
 988 default_autovectorize_vector_sizes (void)
 989 {
 990   return 0;
 991 }
 992
 993 /* Determine whether or not a pointer mode is valid. Assume defaults
 994    of ptr_mode or Pmode - can be overridden.  */
 995 bool
 996 default_valid_pointer_mode (enum machine_mode mode)
 997 {
 998   return (mode == ptr_mode || mode == Pmode);
 999 }
1000
1001 /* Determine whether the memory reference specified by REF may alias
1002    the C libraries errno location.  */
1003 bool
1004 default_ref_may_alias_errno (ao_ref *ref)
1005 {
1006   tree base = ao_ref_base (ref);
1007   /* The default implementation assumes the errno location is
1008      a declaration of type int or is always accessed via a
1009      pointer to int.  We assume that accesses to errno are
1010      not deliberately obfuscated (even in conforming ways).  */
1011   if (TYPE_UNSIGNED (TREE_TYPE (base))
1012       || TYPE_MODE (TREE_TYPE (base)) != TYPE_MODE (integer_type_node))
1013     return false;
1014   /* The default implementation assumes an errno location
1015      declaration is never defined in the current compilation unit.  */
1016   if (DECL_P (base)
1017       && !TREE_STATIC (base))
1018     return true;
1019   else if (TREE_CODE (base) == MEM_REF
1020            && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME)
1021     {
1022       struct ptr_info_def *pi = SSA_NAME_PTR_INFO (TREE_OPERAND (base, 0));
1023       return !pi || pi->pt.anything || pi->pt.nonlocal;
1024     }
1025   return false;
1026 }
1027
1028 /* Return the mode for a pointer to a given ADDRSPACE, defaulting to ptr_mode
1029    for the generic address space only.  */
1030
1031 enum machine_mode
1032 default_addr_space_pointer_mode (addr_space_t addrspace ATTRIBUTE_UNUSED)
1033 {
1034   gcc_assert (ADDR_SPACE_GENERIC_P (addrspace));
1035   return ptr_mode;
1036 }
1037
1038 /* Return the mode for an address in a given ADDRSPACE, defaulting to Pmode
1039    for the generic address space only.  */
1040
1041 enum machine_mode
1042 default_addr_space_address_mode (addr_space_t addrspace ATTRIBUTE_UNUSED)
1043 {
1044   gcc_assert (ADDR_SPACE_GENERIC_P (addrspace));
1045   return Pmode;
1046 }
1047
1048 /* Named address space version of valid_pointer_mode.  */
1049
1050 bool
1051 default_addr_space_valid_pointer_mode (enum machine_mode mode, addr_space_t as)
1052 {
1053   if (!ADDR_SPACE_GENERIC_P (as))
1054     return (mode == targetm.addr_space.pointer_mode (as)
1055             || mode == targetm.addr_space.address_mode (as));
1056
1057   return targetm.valid_pointer_mode (mode);
1058 }
1059
1060 /* Some places still assume that all pointer or address modes are the
1061    standard Pmode and ptr_mode.  These optimizations become invalid if
1062    the target actually supports multiple different modes.  For now,
1063    we disable such optimizations on such targets, using this function.  */
1064
1065 bool
1066 target_default_pointer_address_modes_p (void)
1067 {
1068   if (targetm.addr_space.address_mode != default_addr_space_address_mode)
1069     return false;
1070   if (targetm.addr_space.pointer_mode != default_addr_space_pointer_mode)
1071     return false;
1072
1073   return true;
1074 }
1075
1076 /* Named address space version of legitimate_address_p.  */
1077
1078 bool
1079 default_addr_space_legitimate_address_p (enum machine_mode mode, rtx mem,
1080                                          bool strict, addr_space_t as)
1081 {
1082   if (!ADDR_SPACE_GENERIC_P (as))
1083     gcc_unreachable ();
1084
1085   return targetm.legitimate_address_p (mode, mem, strict);
1086 }
1087
1088 /* Named address space version of LEGITIMIZE_ADDRESS.  */
1089
1090 rtx
1091 default_addr_space_legitimize_address (rtx x, rtx oldx,
1092                                        enum machine_mode mode, addr_space_t as)
1093 {
1094   if (!ADDR_SPACE_GENERIC_P (as))
1095     return x;
1096
1097   return targetm.legitimize_address (x, oldx, mode);
1098 }
1099
1100 /* The default hook for determining if one named address space is a subset of
1101    another and to return which address space to use as the common address
1102    space.  */
1103
1104 bool
1105 default_addr_space_subset_p (addr_space_t subset, addr_space_t superset)
1106 {
1107   return (subset == superset);
1108 }
1109
1110 /* The default hook for TARGET_ADDR_SPACE_CONVERT. This hook should never be
1111    called for targets with only a generic address space.  */
1112
1113 rtx
1114 default_addr_space_convert (rtx op ATTRIBUTE_UNUSED,
1115                             tree from_type ATTRIBUTE_UNUSED,
1116                             tree to_type ATTRIBUTE_UNUSED)
1117 {
1118   gcc_unreachable ();
1119 }
1120
1121 bool
1122 default_hard_regno_scratch_ok (unsigned int regno ATTRIBUTE_UNUSED)
1123 {
1124   return true;
1125 }
1126
1127 /* The default implementation of TARGET_MODE_DEPENDENT_ADDRESS_P.  */
1128
1129 bool
1130 default_mode_dependent_address_p (const_rtx addr ATTRIBUTE_UNUSED)
1131 {
1132 #ifdef GO_IF_MODE_DEPENDENT_ADDRESS
1133
1134   GO_IF_MODE_DEPENDENT_ADDRESS (CONST_CAST_RTX (addr), win);
1135   return false;
1136   /* Label `win' might (not) be used via GO_IF_MODE_DEPENDENT_ADDRESS.  */
1137  win: ATTRIBUTE_UNUSED_LABEL
1138   return true;
1139
1140 #else
1141
1142   return false;
1143
1144 #endif
1145 }
1146
1147 bool
1148 default_target_option_valid_attribute_p (tree ARG_UNUSED (fndecl),
1149                                          tree ARG_UNUSED (name),
1150                                          tree ARG_UNUSED (args),
1151                                          int ARG_UNUSED (flags))
1152 {
1153   warning (OPT_Wattributes,
1154            "target attribute is not supported on this machine");
1155
1156   return false;
1157 }
1158
1159 bool
1160 default_target_option_pragma_parse (tree ARG_UNUSED (args),
1161                                     tree ARG_UNUSED (pop_target))
1162 {
1163   warning (OPT_Wpragmas,
1164            "#pragma GCC target is not supported for this machine");
1165
1166   return false;
1167 }
1168
1169 bool
1170 default_target_can_inline_p (tree caller, tree callee)
1171 {
1172   bool ret = false;
1173   tree callee_opts = DECL_FUNCTION_SPECIFIC_TARGET (callee);
1174   tree caller_opts = DECL_FUNCTION_SPECIFIC_TARGET (caller);
1175
1176   /* If callee has no option attributes, then it is ok to inline */
1177   if (!callee_opts)
1178     ret = true;
1179
1180   /* If caller has no option attributes, but callee does then it is not ok to
1181      inline */
1182   else if (!caller_opts)
1183     ret = false;
1184
1185   /* If both caller and callee have attributes, assume that if the
1186      pointer is different, the two functions have different target
1187      options since build_target_option_node uses a hash table for the
1188      options.  */
1189   else
1190     ret = (callee_opts == caller_opts);
1191
1192   return ret;
1193 }
1194
1195 #ifndef HAVE_casesi
1196 # define HAVE_casesi 0
1197 #endif
1198
1199 /* If the machine does not have a case insn that compares the bounds,
1200    this means extra overhead for dispatch tables, which raises the
1201    threshold for using them.  */
1202
1203 unsigned int default_case_values_threshold (void)
1204 {
1205   return (HAVE_casesi ? 4 : 5);
1206 }
1207
1208 bool
1209 default_have_conditional_execution (void)
1210 {
1211 #ifdef HAVE_conditional_execution
1212   return HAVE_conditional_execution;
1213 #else
1214   return false;
1215 #endif
1216 }
1217
1218 tree
1219 default_builtin_tm_load_store (tree ARG_UNUSED (type))
1220 {
1221   return NULL_TREE;
1222 }
1223
1224 /* Compute cost of moving registers to/from memory.  */
1225
1226 int
1227 default_memory_move_cost (enum machine_mode mode ATTRIBUTE_UNUSED,
1228                           reg_class_t rclass ATTRIBUTE_UNUSED,
1229                           bool in ATTRIBUTE_UNUSED)
1230 {
1231 #ifndef MEMORY_MOVE_COST
1232     return (4 + memory_move_secondary_cost (mode, (enum reg_class) rclass, in));
1233 #else
1234     return MEMORY_MOVE_COST (mode, (enum reg_class) rclass, in);
1235 #endif
1236 }
1237
1238 /* Compute cost of moving data from a register of class FROM to one of
1239    TO, using MODE.  */
1240
1241 int
1242 default_register_move_cost (enum machine_mode mode ATTRIBUTE_UNUSED,
1243                             reg_class_t from ATTRIBUTE_UNUSED,
1244                             reg_class_t to ATTRIBUTE_UNUSED)
1245 {
1246 #ifndef REGISTER_MOVE_COST
1247   return 2;
1248 #else
1249   return REGISTER_MOVE_COST (mode, (enum reg_class) from, (enum reg_class) to);
1250 #endif
1251 }
1252
1253 bool
1254 default_profile_before_prologue (void)
1255 {
1256 #ifdef PROFILE_BEFORE_PROLOGUE
1257   return true;
1258 #else
1259   return false;
1260 #endif
1261 }
1262
1263 /* The default implementation of TARGET_PREFERRED_RELOAD_CLASS.  */
1264
1265 reg_class_t
1266 default_preferred_reload_class (rtx x ATTRIBUTE_UNUSED,
1267                                 reg_class_t rclass)
1268 {
1269 #ifdef PREFERRED_RELOAD_CLASS
1270   return (reg_class_t) PREFERRED_RELOAD_CLASS (x, (enum reg_class) rclass);
1271 #else
1272   return rclass;
1273 #endif
1274 }
1275
1276 /* The default implementation of TARGET_OUTPUT_PREFERRED_RELOAD_CLASS.  */
1277
1278 reg_class_t
1279 default_preferred_output_reload_class (rtx x ATTRIBUTE_UNUSED,
1280                                        reg_class_t rclass)
1281 {
1282   return rclass;
1283 }
1284
1285 /* The default implementation of TARGET_PREFERRED_RENAME_CLASS.  */
1286 reg_class_t
1287 default_preferred_rename_class (reg_class_t rclass ATTRIBUTE_UNUSED)
1288 {
1289   return NO_REGS;
1290 }
1291
1292 /* The default implementation of TARGET_CLASS_LIKELY_SPILLED_P.  */
1293
1294 bool
1295 default_class_likely_spilled_p (reg_class_t rclass)
1296 {
1297   return (reg_class_size[(int) rclass] == 1);
1298 }
1299
1300 /* The default implementation of TARGET_CLASS_MAX_NREGS.  */
1301
1302 unsigned char
1303 default_class_max_nregs (reg_class_t rclass ATTRIBUTE_UNUSED,
1304                          enum machine_mode mode ATTRIBUTE_UNUSED)
1305 {
1306 #ifdef CLASS_MAX_NREGS
1307   return (unsigned char) CLASS_MAX_NREGS ((enum reg_class) rclass, mode);
1308 #else
1309   return ((GET_MODE_SIZE (mode) + UNITS_PER_WORD - 1) / UNITS_PER_WORD);
1310 #endif
1311 }
1312
1313 /* Determine the debugging unwind mechanism for the target.  */
1314
1315 enum unwind_info_type
1316 default_debug_unwind_info (void)
1317 {
1318   /* If the target wants to force the use of dwarf2 unwind info, let it.  */
1319   /* ??? Change all users to the hook, then poison this.  */
1320 #ifdef DWARF2_FRAME_INFO
1321   if (DWARF2_FRAME_INFO)
1322     return UI_DWARF2;
1323 #endif
1324
1325   /* Otherwise, only turn it on if dwarf2 debugging is enabled.  */
1326 #ifdef DWARF2_DEBUGGING_INFO
1327   if (write_symbols == DWARF2_DEBUG || write_symbols == VMS_AND_DWARF2_DEBUG)
1328     return UI_DWARF2;
1329 #endif
1330
1331   return UI_NONE;
1332 }
1333
1334 /* To be used by targets where reg_raw_mode doesn't return the right
1335    mode for registers used in apply_builtin_return and apply_builtin_arg.  */
1336
1337 enum machine_mode
1338 default_get_reg_raw_mode(int regno)
1339 {
1340   return reg_raw_mode[regno];
1341 }
1342
1343 /* Return true if the state of option OPTION should be stored in PCH files
1344    and checked by default_pch_valid_p.  Store the option's current state
1345    in STATE if so.  */
1346
1347 static inline bool
1348 option_affects_pch_p (int option, struct cl_option_state *state)
1349 {
1350   if ((cl_options[option].flags & CL_TARGET) == 0)
1351     return false;
1352   if (option_flag_var (option, &global_options) == &target_flags)
1353     if (targetm.check_pch_target_flags)
1354       return false;
1355   return get_option_state (&global_options, option, state);
1356 }
1357
1358 /* Default version of get_pch_validity.
1359    By default, every flag difference is fatal; that will be mostly right for
1360    most targets, but completely right for very few.  */
1361
1362 void *
1363 default_get_pch_validity (size_t *sz)
1364 {
1365   struct cl_option_state state;
1366   size_t i;
1367   char *result, *r;
1368
1369   *sz = 2;
1370   if (targetm.check_pch_target_flags)
1371     *sz += sizeof (target_flags);
1372   for (i = 0; i < cl_options_count; i++)
1373     if (option_affects_pch_p (i, &state))
1374       *sz += state.size;
1375
1376   result = r = XNEWVEC (char, *sz);
1377   r[0] = flag_pic;
1378   r[1] = flag_pie;
1379   r += 2;
1380   if (targetm.check_pch_target_flags)
1381     {
1382       memcpy (r, &target_flags, sizeof (target_flags));
1383       r += sizeof (target_flags);
1384     }
1385
1386   for (i = 0; i < cl_options_count; i++)
1387     if (option_affects_pch_p (i, &state))
1388       {
1389         memcpy (r, state.data, state.size);
1390         r += state.size;
1391       }
1392
1393   return result;
1394 }
1395
1396 /* Return a message which says that a PCH file was created with a different
1397    setting of OPTION.  */
1398
1399 static const char *
1400 pch_option_mismatch (const char *option)
1401 {
1402   char *r;
1403
1404   asprintf (&r, _("created and used with differing settings of '%s'"), option);
1405   if (r == NULL)
1406     return _("out of memory");
1407   return r;
1408 }
1409
1410 /* Default version of pch_valid_p.  */
1411
1412 const char *
1413 default_pch_valid_p (const void *data_p, size_t len)
1414 {
1415   struct cl_option_state state;
1416   const char *data = (const char *)data_p;
1417   size_t i;
1418
1419   /* -fpic and -fpie also usually make a PCH invalid.  */
1420   if (data[0] != flag_pic)
1421     return _("created and used with different settings of -fpic");
1422   if (data[1] != flag_pie)
1423     return _("created and used with different settings of -fpie");
1424   data += 2;
1425
1426   /* Check target_flags.  */
1427   if (targetm.check_pch_target_flags)
1428     {
1429       int tf;
1430       const char *r;
1431
1432       memcpy (&tf, data, sizeof (target_flags));
1433       data += sizeof (target_flags);
1434       len -= sizeof (target_flags);
1435       r = targetm.check_pch_target_flags (tf);
1436       if (r != NULL)
1437         return r;
1438     }
1439
1440   for (i = 0; i < cl_options_count; i++)
1441     if (option_affects_pch_p (i, &state))
1442       {
1443         if (memcmp (data, state.data, state.size) != 0)
1444           return pch_option_mismatch (cl_options[i].opt_text);
1445         data += state.size;
1446         len -= state.size;
1447       }
1448
1449   return NULL;
1450 }
1451
1452 #include "gt-targhooks.h"