gcc/targhooks.c

   1 /* Default target hook functions.
   2    Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010
   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
  73
  74 bool
  75 default_legitimate_address_p (enum machine_mode mode ATTRIBUTE_UNUSED,
  76                               rtx addr ATTRIBUTE_UNUSED,
  77                               bool strict ATTRIBUTE_UNUSED)
  78 {
  79 #ifdef GO_IF_LEGITIMATE_ADDRESS
  80   /* Defer to the old implementation using a goto.  */
  81   if (strict)
  82     return strict_memory_address_p (mode, addr);
  83   else
  84     return memory_address_p (mode, addr);
  85 #else
  86   gcc_unreachable ();
  87 #endif
  88 }
  89
  90 void
  91 default_external_libcall (rtx fun ATTRIBUTE_UNUSED)
  92 {
  93 #ifdef ASM_OUTPUT_EXTERNAL_LIBCALL
  94   ASM_OUTPUT_EXTERNAL_LIBCALL(asm_out_file, fun);
  95 #endif
  96 }
  97
  98 int
  99 default_unspec_may_trap_p (const_rtx x, unsigned flags)
 100 {
 101   int i;
 102
 103   if (GET_CODE (x) == UNSPEC_VOLATILE
 104       /* Any floating arithmetic may trap.  */
 105       || (SCALAR_FLOAT_MODE_P (GET_MODE (x))
 106           && flag_trapping_math))
 107     return 1;
 108
 109   for (i = 0; i < XVECLEN (x, 0); ++i)
 110     {
 111       if (may_trap_p_1 (XVECEXP (x, 0, i), flags))
 112         return 1;
 113     }
 114
 115   return 0;
 116 }
 117
 118 enum machine_mode
 119 default_promote_function_mode (const_tree type ATTRIBUTE_UNUSED,
 120                                enum machine_mode mode,
 121                                int *punsignedp ATTRIBUTE_UNUSED,
 122                                const_tree funtype ATTRIBUTE_UNUSED,
 123                                int for_return ATTRIBUTE_UNUSED)
 124 {
 125   if (for_return == 2)
 126     return promote_mode (type, mode, punsignedp);
 127   return mode;
 128 }
 129
 130 enum machine_mode
 131 default_promote_function_mode_always_promote (const_tree type,
 132                                               enum machine_mode mode,
 133                                               int *punsignedp,
 134                                               const_tree funtype ATTRIBUTE_UNUSED,
 135                                               int for_return ATTRIBUTE_UNUSED)
 136 {
 137   return promote_mode (type, mode, punsignedp);
 138 }
 139
 140
 141 enum machine_mode
 142 default_cc_modes_compatible (enum machine_mode m1, enum machine_mode m2)
 143 {
 144   if (m1 == m2)
 145     return m1;
 146   return VOIDmode;
 147 }
 148
 149 bool
 150 default_return_in_memory (const_tree type,
 151                           const_tree fntype ATTRIBUTE_UNUSED)
 152 {
 153   return (TYPE_MODE (type) == BLKmode);
 154 }
 155
 156 rtx
 157 default_legitimize_address (rtx x, rtx orig_x ATTRIBUTE_UNUSED,
 158                             enum machine_mode mode ATTRIBUTE_UNUSED)
 159 {
 160   return x;
 161 }
 162
 163 rtx
 164 default_expand_builtin_saveregs (void)
 165 {
 166   error ("__builtin_saveregs not supported by this target");
 167   return const0_rtx;
 168 }
 169
 170 void
 171 default_setup_incoming_varargs (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
 172                                 enum machine_mode mode ATTRIBUTE_UNUSED,
 173                                 tree type ATTRIBUTE_UNUSED,
 174                                 int *pretend_arg_size ATTRIBUTE_UNUSED,
 175                                 int second_time ATTRIBUTE_UNUSED)
 176 {
 177 }
 178
 179 /* The default implementation of TARGET_BUILTIN_SETJMP_FRAME_VALUE.  */
 180
 181 rtx
 182 default_builtin_setjmp_frame_value (void)
 183 {
 184   return virtual_stack_vars_rtx;
 185 }
 186
 187 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns false.  */
 188
 189 bool
 190 hook_bool_CUMULATIVE_ARGS_false (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED)
 191 {
 192   return false;
 193 }
 194
 195 bool
 196 default_pretend_outgoing_varargs_named (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED)
 197 {
 198   return (targetm.calls.setup_incoming_varargs
 199           != default_setup_incoming_varargs);
 200 }
 201
 202 enum machine_mode
 203 default_eh_return_filter_mode (void)
 204 {
 205   return targetm.unwind_word_mode ();
 206 }
 207
 208 enum machine_mode
 209 default_libgcc_cmp_return_mode (void)
 210 {
 211   return word_mode;
 212 }
 213
 214 enum machine_mode
 215 default_libgcc_shift_count_mode (void)
 216 {
 217   return word_mode;
 218 }
 219
 220 enum machine_mode
 221 default_unwind_word_mode (void)
 222 {
 223   return word_mode;
 224 }
 225
 226 /* The default implementation of TARGET_SHIFT_TRUNCATION_MASK.  */
 227
 228 unsigned HOST_WIDE_INT
 229 default_shift_truncation_mask (enum machine_mode mode)
 230 {
 231   return SHIFT_COUNT_TRUNCATED ? GET_MODE_BITSIZE (mode) - 1 : 0;
 232 }
 233
 234 /* The default implementation of TARGET_MIN_DIVISIONS_FOR_RECIP_MUL.  */
 235
 236 unsigned int
 237 default_min_divisions_for_recip_mul (enum machine_mode mode ATTRIBUTE_UNUSED)
 238 {
 239   return have_insn_for (DIV, mode) ? 3 : 2;
 240 }
 241
 242 /* The default implementation of TARGET_MODE_REP_EXTENDED.  */
 243
 244 int
 245 default_mode_rep_extended (enum machine_mode mode ATTRIBUTE_UNUSED,
 246                            enum machine_mode mode_rep ATTRIBUTE_UNUSED)
 247 {
 248   return UNKNOWN;
 249 }
 250
 251 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns true.  */
 252
 253 bool
 254 hook_bool_CUMULATIVE_ARGS_true (CUMULATIVE_ARGS * a ATTRIBUTE_UNUSED)
 255 {
 256   return true;
 257 }
 258
 259 /* Return machine mode for non-standard suffix
 260    or VOIDmode if non-standard suffixes are unsupported.  */
 261 enum machine_mode
 262 default_mode_for_suffix (char suffix ATTRIBUTE_UNUSED)
 263 {
 264   return VOIDmode;
 265 }
 266
 267 /* The generic C++ ABI specifies this is a 64-bit value.  */
 268 tree
 269 default_cxx_guard_type (void)
 270 {
 271   return long_long_integer_type_node;
 272 }
 273
 274
 275 /* Returns the size of the cookie to use when allocating an array
 276    whose elements have the indicated TYPE.  Assumes that it is already
 277    known that a cookie is needed.  */
 278
 279 tree
 280 default_cxx_get_cookie_size (tree type)
 281 {
 282   tree cookie_size;
 283
 284   /* We need to allocate an additional max (sizeof (size_t), alignof
 285      (true_type)) bytes.  */
 286   tree sizetype_size;
 287   tree type_align;
 288
 289   sizetype_size = size_in_bytes (sizetype);
 290   type_align = size_int (TYPE_ALIGN_UNIT (type));
 291   if (INT_CST_LT_UNSIGNED (type_align, sizetype_size))
 292     cookie_size = sizetype_size;
 293   else
 294     cookie_size = type_align;
 295
 296   return cookie_size;
 297 }
 298
 299 /* Return true if a parameter must be passed by reference.  This version
 300    of the TARGET_PASS_BY_REFERENCE hook uses just MUST_PASS_IN_STACK.  */
 301
 302 bool
 303 hook_pass_by_reference_must_pass_in_stack (CUMULATIVE_ARGS *c ATTRIBUTE_UNUSED,
 304         enum machine_mode mode ATTRIBUTE_UNUSED, const_tree type ATTRIBUTE_UNUSED,
 305         bool named_arg ATTRIBUTE_UNUSED)
 306 {
 307   return targetm.calls.must_pass_in_stack (mode, type);
 308 }
 309
 310 /* Return true if a parameter follows callee copies conventions.  This
 311    version of the hook is true for all named arguments.  */
 312
 313 bool
 314 hook_callee_copies_named (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
 315                           enum machine_mode mode ATTRIBUTE_UNUSED,
 316                           const_tree type ATTRIBUTE_UNUSED, bool named)
 317 {
 318   return named;
 319 }
 320
 321 /* Emit to STREAM the assembler syntax for insn operand X.  */
 322
 323 void
 324 default_print_operand (FILE *stream ATTRIBUTE_UNUSED, rtx x ATTRIBUTE_UNUSED,
 325                        int code ATTRIBUTE_UNUSED)
 326 {
 327 #ifdef PRINT_OPERAND
 328   PRINT_OPERAND (stream, x, code);
 329 #else
 330   gcc_unreachable ();
 331 #endif
 332 }
 333
 334 /* Emit to STREAM the assembler syntax for an insn operand whose memory
 335    address is X.  */
 336
 337 void
 338 default_print_operand_address (FILE *stream ATTRIBUTE_UNUSED,
 339                                rtx x ATTRIBUTE_UNUSED)
 340 {
 341 #ifdef PRINT_OPERAND_ADDRESS
 342   PRINT_OPERAND_ADDRESS (stream, x);
 343 #else
 344   gcc_unreachable ();
 345 #endif
 346 }
 347
 348 /* Return true if CODE is a valid punctuation character for the
 349    `print_operand' hook.  */
 350
 351 bool
 352 default_print_operand_punct_valid_p (unsigned char code ATTRIBUTE_UNUSED)
 353 {
 354 #ifdef PRINT_OPERAND_PUNCT_VALID_P
 355   return PRINT_OPERAND_PUNCT_VALID_P (code);
 356 #else
 357   return false;
 358 #endif
 359 }
 360
 361 /* The default implementation of TARGET_MANGLE_ASSEMBLER_NAME.  */
 362 tree
 363 default_mangle_assembler_name (const char *name ATTRIBUTE_UNUSED)
 364 {
 365   const char *skipped = name + (*name == '*' ? 1 : 0);
 366   const char *stripped = targetm.strip_name_encoding (skipped);
 367   if (*name != '*' && user_label_prefix[0])
 368     stripped = ACONCAT ((user_label_prefix, stripped, NULL));
 369   return get_identifier (stripped);
 370 }
 371
 372 /* The default implementation of TARGET_ASM_OUTPUT_ADDR_CONST_EXTRA.  */
 373
 374 bool
 375 default_asm_output_addr_const_extra (FILE *file ATTRIBUTE_UNUSED,
 376                                      rtx x ATTRIBUTE_UNUSED)
 377 {
 378 #ifdef OUTPUT_ADDR_CONST_EXTRA
 379   OUTPUT_ADDR_CONST_EXTRA (file, x, fail);
 380   return true;
 381
 382 fail:
 383 #endif
 384   return false;
 385 }
 386
 387 /* True if MODE is valid for the target.  By "valid", we mean able to
 388    be manipulated in non-trivial ways.  In particular, this means all
 389    the arithmetic is supported.
 390
 391    By default we guess this means that any C type is supported.  If
 392    we can't map the mode back to a type that would be available in C,
 393    then reject it.  Special case, here, is the double-word arithmetic
 394    supported by optabs.c.  */
 395
 396 bool
 397 default_scalar_mode_supported_p (enum machine_mode mode)
 398 {
 399   int precision = GET_MODE_PRECISION (mode);
 400
 401   switch (GET_MODE_CLASS (mode))
 402     {
 403     case MODE_PARTIAL_INT:
 404     case MODE_INT:
 405       if (precision == CHAR_TYPE_SIZE)
 406         return true;
 407       if (precision == SHORT_TYPE_SIZE)
 408         return true;
 409       if (precision == INT_TYPE_SIZE)
 410         return true;
 411       if (precision == LONG_TYPE_SIZE)
 412         return true;
 413       if (precision == LONG_LONG_TYPE_SIZE)
 414         return true;
 415       if (precision == 2 * BITS_PER_WORD)
 416         return true;
 417       return false;
 418
 419     case MODE_FLOAT:
 420       if (precision == FLOAT_TYPE_SIZE)
 421         return true;
 422       if (precision == DOUBLE_TYPE_SIZE)
 423         return true;
 424       if (precision == LONG_DOUBLE_TYPE_SIZE)
 425         return true;
 426       return false;
 427
 428     case MODE_DECIMAL_FLOAT:
 429     case MODE_FRACT:
 430     case MODE_UFRACT:
 431     case MODE_ACCUM:
 432     case MODE_UACCUM:
 433       return false;
 434
 435     default:
 436       gcc_unreachable ();
 437     }
 438 }
 439
 440 /* Make some target macros useable by target-independent code.  */
 441 bool
 442 targhook_words_big_endian (void)
 443 {
 444   return !!WORDS_BIG_ENDIAN;
 445 }
 446
 447 bool
 448 targhook_float_words_big_endian (void)
 449 {
 450   return !!FLOAT_WORDS_BIG_ENDIAN;
 451 }
 452
 453 /* True if the target supports decimal floating point.  */
 454
 455 bool
 456 default_decimal_float_supported_p (void)
 457 {
 458   return ENABLE_DECIMAL_FLOAT;
 459 }
 460
 461 /* True if the target supports fixed-point arithmetic.  */
 462
 463 bool
 464 default_fixed_point_supported_p (void)
 465 {
 466   return ENABLE_FIXED_POINT;
 467 }
 468
 469 /* NULL if INSN insn is valid within a low-overhead loop, otherwise returns
 470    an error message.
 471
 472    This function checks whether a given INSN is valid within a low-overhead
 473    loop.  If INSN is invalid it returns the reason for that, otherwise it
 474    returns NULL. A called function may clobber any special registers required
 475    for low-overhead looping. Additionally, some targets (eg, PPC) use the count
 476    register for branch on table instructions. We reject the doloop pattern in
 477    these cases.  */
 478
 479 const char *
 480 default_invalid_within_doloop (const_rtx insn)
 481 {
 482   if (CALL_P (insn))
 483     return "Function call in loop.";
 484
 485   if (JUMP_TABLE_DATA_P (insn))
 486     return "Computed branch in the loop.";
 487
 488   return NULL;
 489 }
 490
 491 /* Mapping of builtin functions to vectorized variants.  */
 492
 493 tree
 494 default_builtin_vectorized_function (tree fndecl ATTRIBUTE_UNUSED,
 495                                      tree type_out ATTRIBUTE_UNUSED,
 496                                      tree type_in ATTRIBUTE_UNUSED)
 497 {
 498   return NULL_TREE;
 499 }
 500
 501 /* Vectorized conversion.  */
 502
 503 tree
 504 default_builtin_vectorized_conversion (unsigned int code ATTRIBUTE_UNUSED,
 505                                        tree dest_type ATTRIBUTE_UNUSED,
 506                                        tree src_type ATTRIBUTE_UNUSED)
 507 {
 508   return NULL_TREE;
 509 }
 510
 511 /* Default vectorizer cost model values.  */
 512
 513 int
 514 default_builtin_vectorization_cost (enum vect_cost_for_stmt type_of_cost,
 515                                     tree vectype ATTRIBUTE_UNUSED,
 516                                     int misalign ATTRIBUTE_UNUSED)
 517 {
 518   switch (type_of_cost)
 519     {
 520       case scalar_stmt:
 521       case scalar_load:
 522       case scalar_store:
 523       case vector_stmt:
 524       case vector_load:
 525       case vector_store:
 526       case vec_to_scalar:
 527       case scalar_to_vec:
 528       case cond_branch_not_taken:
 529       case vec_perm:
 530         return 1;
 531
 532       case unaligned_load:
 533       case unaligned_store:
 534         return 2;
 535
 536       case cond_branch_taken:
 537         return 3;
 538
 539       default:
 540         gcc_unreachable ();
 541     }
 542 }
 543
 544 /* Reciprocal.  */
 545
 546 tree
 547 default_builtin_reciprocal (unsigned int fn ATTRIBUTE_UNUSED,
 548                             bool md_fn ATTRIBUTE_UNUSED,
 549                             bool sqrt ATTRIBUTE_UNUSED)
 550 {
 551   return NULL_TREE;
 552 }
 553
 554 bool
 555 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false (
 556         CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
 557         enum machine_mode mode ATTRIBUTE_UNUSED,
 558         const_tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
 559 {
 560   return false;
 561 }
 562
 563 bool
 564 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_true (
 565         CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
 566         enum machine_mode mode ATTRIBUTE_UNUSED,
 567         const_tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
 568 {
 569   return true;
 570 }
 571
 572 int
 573 hook_int_CUMULATIVE_ARGS_mode_tree_bool_0 (
 574         CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
 575         enum machine_mode mode ATTRIBUTE_UNUSED,
 576         tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
 577 {
 578   return 0;
 579 }
 580
 581 void
 582 default_function_arg_advance (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
 583                               enum machine_mode mode ATTRIBUTE_UNUSED,
 584                               const_tree type ATTRIBUTE_UNUSED,
 585                               bool named ATTRIBUTE_UNUSED)
 586 {
 587 #ifdef FUNCTION_ARG_ADVANCE
 588   CUMULATIVE_ARGS args = *ca;
 589   FUNCTION_ARG_ADVANCE (args, mode, CONST_CAST_TREE (type), named);
 590   *ca = args;
 591 #else
 592   gcc_unreachable ();
 593 #endif
 594 }
 595
 596 rtx
 597 default_function_arg (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
 598                       enum machine_mode mode ATTRIBUTE_UNUSED,
 599                       const_tree type ATTRIBUTE_UNUSED,
 600                       bool named ATTRIBUTE_UNUSED)
 601 {
 602 #ifdef FUNCTION_ARG
 603   return FUNCTION_ARG (*ca, mode, CONST_CAST_TREE (type), named);
 604 #else
 605   gcc_unreachable ();
 606 #endif
 607 }
 608
 609 rtx
 610 default_function_incoming_arg (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
 611                                enum machine_mode mode ATTRIBUTE_UNUSED,
 612                                const_tree type ATTRIBUTE_UNUSED,
 613                                bool named ATTRIBUTE_UNUSED)
 614 {
 615 #ifdef FUNCTION_INCOMING_ARG
 616   return FUNCTION_INCOMING_ARG (*ca, mode, CONST_CAST_TREE (type), named);
 617 #else
 618   gcc_unreachable ();
 619 #endif
 620 }
 621
 622 unsigned int
 623 default_function_arg_boundary (enum machine_mode mode ATTRIBUTE_UNUSED,
 624                                const_tree type ATTRIBUTE_UNUSED)
 625 {
 626   return PARM_BOUNDARY;
 627 }
 628
 629 void
 630 hook_void_bitmap (bitmap regs ATTRIBUTE_UNUSED)
 631 {
 632 }
 633
 634 const char *
 635 hook_invalid_arg_for_unprototyped_fn (
 636         const_tree typelist ATTRIBUTE_UNUSED,
 637         const_tree funcdecl ATTRIBUTE_UNUSED,
 638         const_tree val ATTRIBUTE_UNUSED)
 639 {
 640   return NULL;
 641 }
 642
 643 /* Initialize the stack protection decls.  */
 644
 645 /* Stack protection related decls living in libgcc.  */
 646 static GTY(()) tree stack_chk_guard_decl;
 647
 648 tree
 649 default_stack_protect_guard (void)
 650 {
 651   tree t = stack_chk_guard_decl;
 652
 653   if (t == NULL)
 654     {
 655       rtx x;
 656
 657       t = build_decl (UNKNOWN_LOCATION,
 658                       VAR_DECL, get_identifier ("__stack_chk_guard"),
 659                       ptr_type_node);
 660       TREE_STATIC (t) = 1;
 661       TREE_PUBLIC (t) = 1;
 662       DECL_EXTERNAL (t) = 1;
 663       TREE_USED (t) = 1;
 664       TREE_THIS_VOLATILE (t) = 1;
 665       DECL_ARTIFICIAL (t) = 1;
 666       DECL_IGNORED_P (t) = 1;
 667
 668       /* Do not share RTL as the declaration is visible outside of
 669          current function.  */
 670       x = DECL_RTL (t);
 671       RTX_FLAG (x, used) = 1;
 672
 673       stack_chk_guard_decl = t;
 674     }
 675
 676   return t;
 677 }
 678
 679 static GTY(()) tree stack_chk_fail_decl;
 680
 681 tree
 682 default_external_stack_protect_fail (void)
 683 {
 684   tree t = stack_chk_fail_decl;
 685
 686   if (t == NULL_TREE)
 687     {
 688       t = build_function_type_list (void_type_node, NULL_TREE);
 689       t = build_decl (UNKNOWN_LOCATION,
 690                       FUNCTION_DECL, get_identifier ("__stack_chk_fail"), t);
 691       TREE_STATIC (t) = 1;
 692       TREE_PUBLIC (t) = 1;
 693       DECL_EXTERNAL (t) = 1;
 694       TREE_USED (t) = 1;
 695       TREE_THIS_VOLATILE (t) = 1;
 696       TREE_NOTHROW (t) = 1;
 697       DECL_ARTIFICIAL (t) = 1;
 698       DECL_IGNORED_P (t) = 1;
 699       DECL_VISIBILITY (t) = VISIBILITY_DEFAULT;
 700       DECL_VISIBILITY_SPECIFIED (t) = 1;
 701
 702       stack_chk_fail_decl = t;
 703     }
 704
 705   return build_call_expr (t, 0);
 706 }
 707
 708 tree
 709 default_hidden_stack_protect_fail (void)
 710 {
 711 #ifndef HAVE_GAS_HIDDEN
 712   return default_external_stack_protect_fail ();
 713 #else
 714   tree t = stack_chk_fail_decl;
 715
 716   if (!flag_pic)
 717     return default_external_stack_protect_fail ();
 718
 719   if (t == NULL_TREE)
 720     {
 721       t = build_function_type_list (void_type_node, NULL_TREE);
 722       t = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL,
 723                       get_identifier ("__stack_chk_fail_local"), t);
 724       TREE_STATIC (t) = 1;
 725       TREE_PUBLIC (t) = 1;
 726       DECL_EXTERNAL (t) = 1;
 727       TREE_USED (t) = 1;
 728       TREE_THIS_VOLATILE (t) = 1;
 729       TREE_NOTHROW (t) = 1;
 730       DECL_ARTIFICIAL (t) = 1;
 731       DECL_IGNORED_P (t) = 1;
 732       DECL_VISIBILITY_SPECIFIED (t) = 1;
 733       DECL_VISIBILITY (t) = VISIBILITY_HIDDEN;
 734
 735       stack_chk_fail_decl = t;
 736     }
 737
 738   return build_call_expr (t, 0);
 739 #endif
 740 }
 741
 742 bool
 743 hook_bool_const_rtx_commutative_p (const_rtx x,
 744                                    int outer_code ATTRIBUTE_UNUSED)
 745 {
 746   return COMMUTATIVE_P (x);
 747 }
 748
 749 rtx
 750 default_function_value (const_tree ret_type ATTRIBUTE_UNUSED,
 751                         const_tree fn_decl_or_type,
 752                         bool outgoing ATTRIBUTE_UNUSED)
 753 {
 754   /* The old interface doesn't handle receiving the function type.  */
 755   if (fn_decl_or_type
 756       && !DECL_P (fn_decl_or_type))
 757     fn_decl_or_type = NULL;
 758
 759 #ifdef FUNCTION_VALUE
 760   return FUNCTION_VALUE (ret_type, fn_decl_or_type);
 761 #else
 762   gcc_unreachable ();
 763 #endif
 764 }
 765
 766 rtx
 767 default_libcall_value (enum machine_mode mode ATTRIBUTE_UNUSED,
 768                        const_rtx fun ATTRIBUTE_UNUSED)
 769 {
 770 #ifdef LIBCALL_VALUE
 771   return LIBCALL_VALUE (mode);
 772 #else
 773   gcc_unreachable ();
 774 #endif
 775 }
 776
 777 /* The default hook for TARGET_FUNCTION_VALUE_REGNO_P.  */
 778
 779 bool
 780 default_function_value_regno_p (const unsigned int regno ATTRIBUTE_UNUSED)
 781 {
 782 #ifdef FUNCTION_VALUE_REGNO_P
 783   return FUNCTION_VALUE_REGNO_P (regno);
 784 #else
 785   gcc_unreachable ();
 786 #endif
 787 }
 788
 789 rtx
 790 default_internal_arg_pointer (void)
 791 {
 792   /* If the reg that the virtual arg pointer will be translated into is
 793      not a fixed reg or is the stack pointer, make a copy of the virtual
 794      arg pointer, and address parms via the copy.  The frame pointer is
 795      considered fixed even though it is not marked as such.  */
 796   if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
 797        || ! (fixed_regs[ARG_POINTER_REGNUM]
 798              || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
 799     return copy_to_reg (virtual_incoming_args_rtx);
 800   else
 801     return virtual_incoming_args_rtx;
 802 }
 803
 804 rtx
 805 default_static_chain (const_tree fndecl, bool incoming_p)
 806 {
 807   if (!DECL_STATIC_CHAIN (fndecl))
 808     return NULL;
 809
 810   if (incoming_p)
 811     {
 812 #ifdef STATIC_CHAIN_INCOMING_REGNUM
 813       return gen_rtx_REG (Pmode, STATIC_CHAIN_INCOMING_REGNUM);
 814 #endif
 815     }
 816
 817 #ifdef STATIC_CHAIN_REGNUM
 818   return gen_rtx_REG (Pmode, STATIC_CHAIN_REGNUM);
 819 #endif
 820
 821   {
 822     static bool issued_error;
 823     if (!issued_error)
 824       {
 825         issued_error = true;
 826         sorry ("nested functions not supported on this target");
 827       }
 828
 829     /* It really doesn't matter what we return here, so long at it
 830        doesn't cause the rest of the compiler to crash.  */
 831     return gen_rtx_MEM (Pmode, stack_pointer_rtx);
 832   }
 833 }
 834
 835 void
 836 default_trampoline_init (rtx ARG_UNUSED (m_tramp), tree ARG_UNUSED (t_func),
 837                          rtx ARG_UNUSED (r_chain))
 838 {
 839   sorry ("nested function trampolines not supported on this target");
 840 }
 841
 842 int
 843 default_return_pops_args (tree fundecl ATTRIBUTE_UNUSED,
 844                           tree funtype ATTRIBUTE_UNUSED,
 845                           int size ATTRIBUTE_UNUSED)
 846 {
 847   return 0;
 848 }
 849
 850 reg_class_t
 851 default_branch_target_register_class (void)
 852 {
 853   return NO_REGS;
 854 }
 855
 856 #ifdef IRA_COVER_CLASSES
 857 const reg_class_t *
 858 default_ira_cover_classes (void)
 859 {
 860   static reg_class_t classes[] = IRA_COVER_CLASSES;
 861   return classes;
 862 }
 863 #endif
 864
 865 reg_class_t
 866 default_secondary_reload (bool in_p ATTRIBUTE_UNUSED, rtx x ATTRIBUTE_UNUSED,
 867                           reg_class_t reload_class_i ATTRIBUTE_UNUSED,
 868                           enum machine_mode reload_mode ATTRIBUTE_UNUSED,
 869                           secondary_reload_info *sri)
 870 {
 871   enum reg_class rclass = NO_REGS;
 872   enum reg_class reload_class = (enum reg_class) reload_class_i;
 873
 874   if (sri->prev_sri && sri->prev_sri->t_icode != CODE_FOR_nothing)
 875     {
 876       sri->icode = sri->prev_sri->t_icode;
 877       return NO_REGS;
 878     }
 879 #ifdef SECONDARY_INPUT_RELOAD_CLASS
 880   if (in_p)
 881     rclass = SECONDARY_INPUT_RELOAD_CLASS (reload_class, reload_mode, x);
 882 #endif
 883 #ifdef SECONDARY_OUTPUT_RELOAD_CLASS
 884   if (! in_p)
 885     rclass = SECONDARY_OUTPUT_RELOAD_CLASS (reload_class, reload_mode, x);
 886 #endif
 887   if (rclass != NO_REGS)
 888     {
 889       enum insn_code icode
 890         = direct_optab_handler (in_p ? reload_in_optab : reload_out_optab,
 891                                 reload_mode);
 892
 893       if (icode != CODE_FOR_nothing
 894           && insn_data[(int) icode].operand[in_p].predicate
 895           && ! insn_data[(int) icode].operand[in_p].predicate (x, reload_mode))
 896         icode = CODE_FOR_nothing;
 897       else if (icode != CODE_FOR_nothing)
 898         {
 899           const char *insn_constraint, *scratch_constraint;
 900           char insn_letter, scratch_letter;
 901           enum reg_class insn_class, scratch_class;
 902
 903           gcc_assert (insn_data[(int) icode].n_operands == 3);
 904           insn_constraint = insn_data[(int) icode].operand[!in_p].constraint;
 905           if (!*insn_constraint)
 906             insn_class = ALL_REGS;
 907           else
 908             {
 909               if (in_p)
 910                 {
 911                   gcc_assert (*insn_constraint == '=');
 912                   insn_constraint++;
 913                 }
 914               insn_letter = *insn_constraint;
 915               insn_class
 916                 = (insn_letter == 'r' ? GENERAL_REGS
 917                    : REG_CLASS_FROM_CONSTRAINT ((unsigned char) insn_letter,
 918                                                 insn_constraint));
 919               gcc_assert (insn_class != NO_REGS);
 920             }
 921
 922           scratch_constraint = insn_data[(int) icode].operand[2].constraint;
 923           /* The scratch register's constraint must start with "=&",
 924              except for an input reload, where only "=" is necessary,
 925              and where it might be beneficial to re-use registers from
 926              the input.  */
 927           gcc_assert (scratch_constraint[0] == '='
 928                       && (in_p || scratch_constraint[1] == '&'));
 929           scratch_constraint++;
 930           if (*scratch_constraint == '&')
 931             scratch_constraint++;
 932           scratch_letter = *scratch_constraint;
 933           scratch_class
 934             = (scratch_letter == 'r' ? GENERAL_REGS
 935                : REG_CLASS_FROM_CONSTRAINT ((unsigned char) scratch_letter,
 936                                             scratch_constraint));
 937
 938           if (reg_class_subset_p (reload_class, insn_class))
 939             {
 940               gcc_assert (scratch_class == rclass);
 941               rclass = NO_REGS;
 942             }
 943           else
 944             rclass = insn_class;
 945
 946         }
 947       if (rclass == NO_REGS)
 948         sri->icode = icode;
 949       else
 950         sri->t_icode = icode;
 951     }
 952   return rclass;
 953 }
 954
 955 bool
 956 default_handle_c_option (size_t code ATTRIBUTE_UNUSED,
 957                          const char *arg ATTRIBUTE_UNUSED,
 958                          int value ATTRIBUTE_UNUSED)
 959 {
 960   return false;
 961 }
 962
 963 /* By default, if flag_pic is true, then neither local nor global relocs
 964    should be placed in readonly memory.  */
 965
 966 int
 967 default_reloc_rw_mask (void)
 968 {
 969   return flag_pic ? 3 : 0;
 970 }
 971
 972 /* By default, do no modification. */
 973 tree default_mangle_decl_assembler_name (tree decl ATTRIBUTE_UNUSED,
 974                                          tree id)
 975 {
 976    return id;
 977 }
 978
 979 bool
 980 default_builtin_vector_alignment_reachable (const_tree type, bool is_packed)
 981 {
 982   if (is_packed)
 983     return false;
 984
 985   /* Assuming that types whose size is > pointer-size are not guaranteed to be
 986      naturally aligned.  */
 987   if (tree_int_cst_compare (TYPE_SIZE (type), bitsize_int (POINTER_SIZE)) > 0)
 988     return false;
 989
 990   /* Assuming that types whose size is <= pointer-size
 991      are naturally aligned.  */
 992   return true;
 993 }
 994
 995 /* By default, assume that a target supports any factor of misalignment
 996    memory access if it supports movmisalign patten.
 997    is_packed is true if the memory access is defined in a packed struct.  */
 998 bool
 999 default_builtin_support_vector_misalignment (enum machine_mode mode,
1000                                              const_tree type
1001                                              ATTRIBUTE_UNUSED,
1002                                              int misalignment
1003                                              ATTRIBUTE_UNUSED,
1004                                              bool is_packed
1005                                              ATTRIBUTE_UNUSED)
1006 {
1007   if (optab_handler (movmisalign_optab, mode) != CODE_FOR_nothing)
1008     return true;
1009   return false;
1010 }
1011
1012 /* By default, only attempt to parallelize bitwise operations, and
1013    possibly adds/subtracts using bit-twiddling.  */
1014
1015 enum machine_mode
1016 default_preferred_simd_mode (enum machine_mode mode ATTRIBUTE_UNUSED)
1017 {
1018   return word_mode;
1019 }
1020
1021 /* By default only the size derived from the preferred vector mode
1022    is tried.  */
1023
1024 unsigned int
1025 default_autovectorize_vector_sizes (void)
1026 {
1027   return 0;
1028 }
1029
1030 /* Determine whether or not a pointer mode is valid. Assume defaults
1031    of ptr_mode or Pmode - can be overridden.  */
1032 bool
1033 default_valid_pointer_mode (enum machine_mode mode)
1034 {
1035   return (mode == ptr_mode || mode == Pmode);
1036 }
1037
1038 /* Return the mode for a pointer to a given ADDRSPACE, defaulting to ptr_mode
1039    for the generic address space only.  */
1040
1041 enum machine_mode
1042 default_addr_space_pointer_mode (addr_space_t addrspace ATTRIBUTE_UNUSED)
1043 {
1044   gcc_assert (ADDR_SPACE_GENERIC_P (addrspace));
1045   return ptr_mode;
1046 }
1047
1048 /* Return the mode for an address in a given ADDRSPACE, defaulting to Pmode
1049    for the generic address space only.  */
1050
1051 enum machine_mode
1052 default_addr_space_address_mode (addr_space_t addrspace ATTRIBUTE_UNUSED)
1053 {
1054   gcc_assert (ADDR_SPACE_GENERIC_P (addrspace));
1055   return Pmode;
1056 }
1057
1058 /* Named address space version of valid_pointer_mode.  */
1059
1060 bool
1061 default_addr_space_valid_pointer_mode (enum machine_mode mode, addr_space_t as)
1062 {
1063   if (!ADDR_SPACE_GENERIC_P (as))
1064     return (mode == targetm.addr_space.pointer_mode (as)
1065             || mode == targetm.addr_space.address_mode (as));
1066
1067   return targetm.valid_pointer_mode (mode);
1068 }
1069
1070 /* Some places still assume that all pointer or address modes are the
1071    standard Pmode and ptr_mode.  These optimizations become invalid if
1072    the target actually supports multiple different modes.  For now,
1073    we disable such optimizations on such targets, using this function.  */
1074
1075 bool
1076 target_default_pointer_address_modes_p (void)
1077 {
1078   if (targetm.addr_space.address_mode != default_addr_space_address_mode)
1079     return false;
1080   if (targetm.addr_space.pointer_mode != default_addr_space_pointer_mode)
1081     return false;
1082
1083   return true;
1084 }
1085
1086 /* Named address space version of legitimate_address_p.  */
1087
1088 bool
1089 default_addr_space_legitimate_address_p (enum machine_mode mode, rtx mem,
1090                                          bool strict, addr_space_t as)
1091 {
1092   if (!ADDR_SPACE_GENERIC_P (as))
1093     gcc_unreachable ();
1094
1095   return targetm.legitimate_address_p (mode, mem, strict);
1096 }
1097
1098 /* Named address space version of LEGITIMIZE_ADDRESS.  */
1099
1100 rtx
1101 default_addr_space_legitimize_address (rtx x, rtx oldx,
1102                                        enum machine_mode mode, addr_space_t as)
1103 {
1104   if (!ADDR_SPACE_GENERIC_P (as))
1105     return x;
1106
1107   return targetm.legitimize_address (x, oldx, mode);
1108 }
1109
1110 /* The default hook for determining if one named address space is a subset of
1111    another and to return which address space to use as the common address
1112    space.  */
1113
1114 bool
1115 default_addr_space_subset_p (addr_space_t subset, addr_space_t superset)
1116 {
1117   return (subset == superset);
1118 }
1119
1120 /* The default hook for TARGET_ADDR_SPACE_CONVERT. This hook should never be
1121    called for targets with only a generic address space.  */
1122
1123 rtx
1124 default_addr_space_convert (rtx op ATTRIBUTE_UNUSED,
1125                             tree from_type ATTRIBUTE_UNUSED,
1126                             tree to_type ATTRIBUTE_UNUSED)
1127 {
1128   gcc_unreachable ();
1129 }
1130
1131 bool
1132 default_hard_regno_scratch_ok (unsigned int regno ATTRIBUTE_UNUSED)
1133 {
1134   return true;
1135 }
1136
1137 /* The default implementation of TARGET_MODE_DEPENDENT_ADDRESS_P.  */
1138
1139 bool
1140 default_mode_dependent_address_p (const_rtx addr ATTRIBUTE_UNUSED)
1141 {
1142 #ifdef GO_IF_MODE_DEPENDENT_ADDRESS
1143
1144   GO_IF_MODE_DEPENDENT_ADDRESS (CONST_CAST_RTX (addr), win);
1145   return false;
1146   /* Label `win' might (not) be used via GO_IF_MODE_DEPENDENT_ADDRESS.  */
1147  win: ATTRIBUTE_UNUSED_LABEL
1148   return true;
1149
1150 #else
1151
1152   return false;
1153
1154 #endif
1155 }
1156
1157 bool
1158 default_target_option_valid_attribute_p (tree ARG_UNUSED (fndecl),
1159                                          tree ARG_UNUSED (name),
1160                                          tree ARG_UNUSED (args),
1161                                          int ARG_UNUSED (flags))
1162 {
1163   warning (OPT_Wattributes,
1164            "target attribute is not supported on this machine");
1165
1166   return false;
1167 }
1168
1169 bool
1170 default_target_option_pragma_parse (tree ARG_UNUSED (args),
1171                                     tree ARG_UNUSED (pop_target))
1172 {
1173   warning (OPT_Wpragmas,
1174            "#pragma GCC target is not supported for this machine");
1175
1176   return false;
1177 }
1178
1179 bool
1180 default_target_can_inline_p (tree caller, tree callee)
1181 {
1182   bool ret = false;
1183   tree callee_opts = DECL_FUNCTION_SPECIFIC_TARGET (callee);
1184   tree caller_opts = DECL_FUNCTION_SPECIFIC_TARGET (caller);
1185
1186   /* If callee has no option attributes, then it is ok to inline */
1187   if (!callee_opts)
1188     ret = true;
1189
1190   /* If caller has no option attributes, but callee does then it is not ok to
1191      inline */
1192   else if (!caller_opts)
1193     ret = false;
1194
1195   /* If both caller and callee have attributes, assume that if the pointer is
1196      different, the the two functions have different target options since
1197      build_target_option_node uses a hash table for the options.  */
1198   else
1199     ret = (callee_opts == caller_opts);
1200
1201   return ret;
1202 }
1203
1204 #ifndef HAVE_casesi
1205 # define HAVE_casesi 0
1206 #endif
1207
1208 /* If the machine does not have a case insn that compares the bounds,
1209    this means extra overhead for dispatch tables, which raises the
1210    threshold for using them.  */
1211
1212 unsigned int default_case_values_threshold (void)
1213 {
1214   return (HAVE_casesi ? 4 : 5);
1215 }
1216
1217 bool
1218 default_have_conditional_execution (void)
1219 {
1220 #ifdef HAVE_conditional_execution
1221   return HAVE_conditional_execution;
1222 #else
1223   return false;
1224 #endif
1225 }
1226
1227 /* Compute cost of moving registers to/from memory.  */
1228
1229 int
1230 default_memory_move_cost (enum machine_mode mode ATTRIBUTE_UNUSED,
1231                           reg_class_t rclass ATTRIBUTE_UNUSED,
1232                           bool in ATTRIBUTE_UNUSED)
1233 {
1234 #ifndef MEMORY_MOVE_COST
1235     return (4 + memory_move_secondary_cost (mode, (enum reg_class) rclass, in));
1236 #else
1237     return MEMORY_MOVE_COST (mode, (enum reg_class) rclass, in);
1238 #endif
1239 }
1240
1241 /* Compute cost of moving data from a register of class FROM to one of
1242    TO, using MODE.  */
1243
1244 int
1245 default_register_move_cost (enum machine_mode mode ATTRIBUTE_UNUSED,
1246                             reg_class_t from ATTRIBUTE_UNUSED,
1247                             reg_class_t to ATTRIBUTE_UNUSED)
1248 {
1249 #ifndef REGISTER_MOVE_COST
1250   return 2;
1251 #else
1252   return REGISTER_MOVE_COST (mode, (enum reg_class) from, (enum reg_class) to);
1253 #endif
1254 }
1255
1256 bool
1257 default_profile_before_prologue (void)
1258 {
1259 #ifdef PROFILE_BEFORE_PROLOGUE
1260   return true;
1261 #else
1262   return false;
1263 #endif
1264 }
1265
1266 /* The default implementation of TARGET_PREFERRED_RELOAD_CLASS.  */
1267
1268 reg_class_t
1269 default_preferred_reload_class (rtx x ATTRIBUTE_UNUSED,
1270                                 reg_class_t rclass)
1271 {
1272 #ifdef PREFERRED_RELOAD_CLASS
1273   return (reg_class_t) PREFERRED_RELOAD_CLASS (x, (enum reg_class) rclass);
1274 #else
1275   return rclass;
1276 #endif
1277 }
1278
1279 /* The default implementation of TARGET_OUTPUT_PREFERRED_RELOAD_CLASS.  */
1280
1281 reg_class_t
1282 default_preferred_output_reload_class (rtx x ATTRIBUTE_UNUSED,
1283                                        reg_class_t rclass)
1284 {
1285 #ifdef PREFERRED_OUTPUT_RELOAD_CLASS
1286   return PREFERRED_OUTPUT_RELOAD_CLASS (x, (enum reg_class) rclass);
1287 #else
1288   return rclass;
1289 #endif
1290 }
1291
1292 /* The default implementation of TARGET_PREFERRED_RENAME_CLASS.  */
1293 reg_class_t
1294 default_preferred_rename_class (reg_class_t rclass ATTRIBUTE_UNUSED)
1295 {
1296   return NO_REGS;
1297 }
1298
1299 /* The default implementation of TARGET_CLASS_LIKELY_SPILLED_P.  */
1300
1301 bool
1302 default_class_likely_spilled_p (reg_class_t rclass)
1303 {
1304   return (reg_class_size[(int) rclass] == 1);
1305 }
1306
1307 /* Determine the debugging unwind mechanism for the target.  */
1308
1309 enum unwind_info_type
1310 default_debug_unwind_info (void)
1311 {
1312   /* If the target wants to force the use of dwarf2 unwind info, let it.  */
1313   /* ??? Change all users to the hook, then poison this.  */
1314 #ifdef DWARF2_FRAME_INFO
1315   if (DWARF2_FRAME_INFO)
1316     return UI_DWARF2;
1317 #endif
1318
1319   /* Otherwise, only turn it on if dwarf2 debugging is enabled.  */
1320 #ifdef DWARF2_DEBUGGING_INFO
1321   if (write_symbols == DWARF2_DEBUG || write_symbols == VMS_AND_DWARF2_DEBUG)
1322     return UI_DWARF2;
1323 #endif
1324
1325   return UI_NONE;
1326 }
1327
1328 /* Determine the exception handling mechanism for the target.  */
1329
1330 enum unwind_info_type
1331 default_except_unwind_info (struct gcc_options *opts ATTRIBUTE_UNUSED)
1332 {
1333   /* Obey the configure switch to turn on sjlj exceptions.  */
1334 #ifdef CONFIG_SJLJ_EXCEPTIONS
1335   if (CONFIG_SJLJ_EXCEPTIONS)
1336     return UI_SJLJ;
1337 #endif
1338
1339   /* ??? Change all users to the hook, then poison this.  */
1340 #ifdef DWARF2_UNWIND_INFO
1341   if (DWARF2_UNWIND_INFO)
1342     return UI_DWARF2;
1343 #endif
1344
1345   return UI_SJLJ;
1346 }
1347
1348 /* To be used by targets that force dwarf2 unwind enabled.  */
1349
1350 enum unwind_info_type
1351 dwarf2_except_unwind_info (struct gcc_options *opts ATTRIBUTE_UNUSED)
1352 {
1353   /* Obey the configure switch to turn on sjlj exceptions.  */
1354 #ifdef CONFIG_SJLJ_EXCEPTIONS
1355   if (CONFIG_SJLJ_EXCEPTIONS)
1356     return UI_SJLJ;
1357 #endif
1358
1359   return UI_DWARF2;
1360 }
1361
1362 /* To be used by targets that force sjlj unwind enabled.  */
1363
1364 enum unwind_info_type
1365 sjlj_except_unwind_info (struct gcc_options *opts ATTRIBUTE_UNUSED)
1366 {
1367   return UI_SJLJ;
1368 }
1369
1370 /* To be used by targets where reg_raw_mode doesn't return the right
1371    mode for registers used in apply_builtin_return and apply_builtin_arg.  */
1372
1373 enum machine_mode
1374 default_get_reg_raw_mode(int regno)
1375 {
1376   return reg_raw_mode[regno];
1377 }
1378
1379 /* Return true if the state of option OPTION should be stored in PCH files
1380    and checked by default_pch_valid_p.  Store the option's current state
1381    in STATE if so.  */
1382
1383 static inline bool
1384 option_affects_pch_p (int option, struct cl_option_state *state)
1385 {
1386   if ((cl_options[option].flags & CL_TARGET) == 0)
1387     return false;
1388   if (option_flag_var (option, &global_options) == &target_flags)
1389     if (targetm.check_pch_target_flags)
1390       return false;
1391   return get_option_state (&global_options, option, state);
1392 }
1393
1394 /* Default version of get_pch_validity.
1395    By default, every flag difference is fatal; that will be mostly right for
1396    most targets, but completely right for very few.  */
1397
1398 void *
1399 default_get_pch_validity (size_t *sz)
1400 {
1401   struct cl_option_state state;
1402   size_t i;
1403   char *result, *r;
1404
1405   *sz = 2;
1406   if (targetm.check_pch_target_flags)
1407     *sz += sizeof (target_flags);
1408   for (i = 0; i < cl_options_count; i++)
1409     if (option_affects_pch_p (i, &state))
1410       *sz += state.size;
1411
1412   result = r = XNEWVEC (char, *sz);
1413   r[0] = flag_pic;
1414   r[1] = flag_pie;
1415   r += 2;
1416   if (targetm.check_pch_target_flags)
1417     {
1418       memcpy (r, &target_flags, sizeof (target_flags));
1419       r += sizeof (target_flags);
1420     }
1421
1422   for (i = 0; i < cl_options_count; i++)
1423     if (option_affects_pch_p (i, &state))
1424       {
1425         memcpy (r, state.data, state.size);
1426         r += state.size;
1427       }
1428
1429   return result;
1430 }
1431
1432 /* Return a message which says that a PCH file was created with a different
1433    setting of OPTION.  */
1434
1435 static const char *
1436 pch_option_mismatch (const char *option)
1437 {
1438   char *r;
1439
1440   asprintf (&r, _("created and used with differing settings of '%s'"), option);
1441   if (r == NULL)
1442     return _("out of memory");
1443   return r;
1444 }
1445
1446 /* Default version of pch_valid_p.  */
1447
1448 const char *
1449 default_pch_valid_p (const void *data_p, size_t len)
1450 {
1451   struct cl_option_state state;
1452   const char *data = (const char *)data_p;
1453   size_t i;
1454
1455   /* -fpic and -fpie also usually make a PCH invalid.  */
1456   if (data[0] != flag_pic)
1457     return _("created and used with different settings of -fpic");
1458   if (data[1] != flag_pie)
1459     return _("created and used with different settings of -fpie");
1460   data += 2;
1461
1462   /* Check target_flags.  */
1463   if (targetm.check_pch_target_flags)
1464     {
1465       int tf;
1466       const char *r;
1467
1468       memcpy (&tf, data, sizeof (target_flags));
1469       data += sizeof (target_flags);
1470       len -= sizeof (target_flags);
1471       r = targetm.check_pch_target_flags (tf);
1472       if (r != NULL)
1473         return r;
1474     }
1475
1476   for (i = 0; i < cl_options_count; i++)
1477     if (option_affects_pch_p (i, &state))
1478       {
1479         if (memcmp (data, state.data, state.size) != 0)
1480           return pch_option_mismatch (cl_options[i].opt_text);
1481         data += state.size;
1482         len -= state.size;
1483       }
1484
1485   return NULL;
1486 }
1487
1488 const struct default_options empty_optimization_table[] =
1489   {
1490     { OPT_LEVELS_NONE, 0, NULL, 0 }
1491   };
1492
1493 #include "gt-targhooks.h"