gcc/targhooks.c

   1 /* Default target hook functions.
   2    Copyright (C) 2003-2014 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 /* The migration of target macros to target hooks works as follows:
  21
  22    1. Create a target hook that uses the existing target macros to
  23       implement the same functionality.
  24
  25    2. Convert all the MI files to use the hook instead of the macro.
  26
  27    3. Repeat for a majority of the remaining target macros.  This will
  28       take some time.
  29
  30    4. Tell target maintainers to start migrating.
  31
  32    5. Eventually convert the backends to override the hook instead of
  33       defining the macros.  This will take some time too.
  34
  35    6. TBD when, poison the macros.  Unmigrated targets will break at
  36       this point.
  37
  38    Note that we expect steps 1-3 to be done by the people that
  39    understand what the MI does with each macro, and step 5 to be done
  40    by the target maintainers for their respective targets.
  41
  42    Note that steps 1 and 2 don't have to be done together, but no
  43    target can override the new hook until step 2 is complete for it.
  44
  45    Once the macros are poisoned, we will revert to the old migration
  46    rules - migrate the macro, callers, and targets all at once.  This
  47    comment can thus be removed at that point.  */
  48
  49 #include "config.h"
  50 #include "system.h"
  51 #include "coretypes.h"
  52 #include "tm.h"
  53 #include "machmode.h"
  54 #include "rtl.h"
  55 #include "tree.h"
  56 #include "stor-layout.h"
  57 #include "varasm.h"
  58 #include "expr.h"
  59 #include "output.h"
  60 #include "diagnostic-core.h"
  61 #include "hashtab.h"
  62 #include "hash-set.h"
  63 #include "vec.h"
  64 #include "hard-reg-set.h"
  65 #include "input.h"
  66 #include "function.h"
  67 #include "target.h"
  68 #include "tm_p.h"
  69 #include "target-def.h"
  70 #include "regs.h"
  71 #include "reload.h"
  72 #include "insn-codes.h"
  73 #include "optabs.h"
  74 #include "recog.h"
  75 #include "intl.h"
  76 #include "opts.h"
  77 #include "tree-ssa-alias.h"
  78 #include "gimple-expr.h"
  79 #include "gimplify.h"
  80 #include "stringpool.h"
  81 #include "tree-ssanames.h"
  82
  83
  84 bool
  85 default_legitimate_address_p (machine_mode mode ATTRIBUTE_UNUSED,
  86                               rtx addr ATTRIBUTE_UNUSED,
  87                               bool strict ATTRIBUTE_UNUSED)
  88 {
  89 #ifdef GO_IF_LEGITIMATE_ADDRESS
  90   /* Defer to the old implementation using a goto.  */
  91   if (strict)
  92     return strict_memory_address_p (mode, addr);
  93   else
  94     return memory_address_p (mode, addr);
  95 #else
  96   gcc_unreachable ();
  97 #endif
  98 }
  99
 100 void
 101 default_external_libcall (rtx fun ATTRIBUTE_UNUSED)
 102 {
 103 #ifdef ASM_OUTPUT_EXTERNAL_LIBCALL
 104   ASM_OUTPUT_EXTERNAL_LIBCALL (asm_out_file, fun);
 105 #endif
 106 }
 107
 108 int
 109 default_unspec_may_trap_p (const_rtx x, unsigned flags)
 110 {
 111   int i;
 112
 113   /* Any floating arithmetic may trap.  */
 114   if ((SCALAR_FLOAT_MODE_P (GET_MODE (x)) && flag_trapping_math))
 115     return 1;
 116
 117   for (i = 0; i < XVECLEN (x, 0); ++i)
 118     {
 119       if (may_trap_p_1 (XVECEXP (x, 0, i), flags))
 120         return 1;
 121     }
 122
 123   return 0;
 124 }
 125
 126 machine_mode
 127 default_promote_function_mode (const_tree type ATTRIBUTE_UNUSED,
 128                                machine_mode mode,
 129                                int *punsignedp ATTRIBUTE_UNUSED,
 130                                const_tree funtype ATTRIBUTE_UNUSED,
 131                                int for_return ATTRIBUTE_UNUSED)
 132 {
 133   if (type != NULL_TREE && for_return == 2)
 134     return promote_mode (type, mode, punsignedp);
 135   return mode;
 136 }
 137
 138 machine_mode
 139 default_promote_function_mode_always_promote (const_tree type,
 140                                               machine_mode mode,
 141                                               int *punsignedp,
 142                                               const_tree funtype ATTRIBUTE_UNUSED,
 143                                               int for_return ATTRIBUTE_UNUSED)
 144 {
 145   return promote_mode (type, mode, punsignedp);
 146 }
 147
 148 machine_mode
 149 default_cc_modes_compatible (machine_mode m1, machine_mode m2)
 150 {
 151   if (m1 == m2)
 152     return m1;
 153   return VOIDmode;
 154 }
 155
 156 bool
 157 default_return_in_memory (const_tree type,
 158                           const_tree fntype ATTRIBUTE_UNUSED)
 159 {
 160   return (TYPE_MODE (type) == BLKmode);
 161 }
 162
 163 rtx
 164 default_legitimize_address (rtx x, rtx orig_x ATTRIBUTE_UNUSED,
 165                             machine_mode mode ATTRIBUTE_UNUSED)
 166 {
 167   return x;
 168 }
 169
 170 bool
 171 default_legitimize_address_displacement (rtx *disp ATTRIBUTE_UNUSED,
 172                                          rtx *offset ATTRIBUTE_UNUSED,
 173                                          machine_mode mode ATTRIBUTE_UNUSED)
 174 {
 175   return false;
 176 }
 177
 178 rtx
 179 default_expand_builtin_saveregs (void)
 180 {
 181   error ("__builtin_saveregs not supported by this target");
 182   return const0_rtx;
 183 }
 184
 185 void
 186 default_setup_incoming_varargs (cumulative_args_t ca ATTRIBUTE_UNUSED,
 187                                 machine_mode mode ATTRIBUTE_UNUSED,
 188                                 tree type ATTRIBUTE_UNUSED,
 189                                 int *pretend_arg_size ATTRIBUTE_UNUSED,
 190                                 int second_time ATTRIBUTE_UNUSED)
 191 {
 192 }
 193
 194 /* The default implementation of TARGET_BUILTIN_SETJMP_FRAME_VALUE.  */
 195
 196 rtx
 197 default_builtin_setjmp_frame_value (void)
 198 {
 199   return virtual_stack_vars_rtx;
 200 }
 201
 202 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns false.  */
 203
 204 bool
 205 hook_bool_CUMULATIVE_ARGS_false (cumulative_args_t ca ATTRIBUTE_UNUSED)
 206 {
 207   return false;
 208 }
 209
 210 bool
 211 default_pretend_outgoing_varargs_named (cumulative_args_t ca ATTRIBUTE_UNUSED)
 212 {
 213   return (targetm.calls.setup_incoming_varargs
 214           != default_setup_incoming_varargs);
 215 }
 216
 217 machine_mode
 218 default_eh_return_filter_mode (void)
 219 {
 220   return targetm.unwind_word_mode ();
 221 }
 222
 223 machine_mode
 224 default_libgcc_cmp_return_mode (void)
 225 {
 226   return word_mode;
 227 }
 228
 229 machine_mode
 230 default_libgcc_shift_count_mode (void)
 231 {
 232   return word_mode;
 233 }
 234
 235 machine_mode
 236 default_unwind_word_mode (void)
 237 {
 238   return word_mode;
 239 }
 240
 241 /* The default implementation of TARGET_SHIFT_TRUNCATION_MASK.  */
 242
 243 unsigned HOST_WIDE_INT
 244 default_shift_truncation_mask (machine_mode mode)
 245 {
 246   return SHIFT_COUNT_TRUNCATED ? GET_MODE_BITSIZE (mode) - 1 : 0;
 247 }
 248
 249 /* The default implementation of TARGET_MIN_DIVISIONS_FOR_RECIP_MUL.  */
 250
 251 unsigned int
 252 default_min_divisions_for_recip_mul (machine_mode mode ATTRIBUTE_UNUSED)
 253 {
 254   return have_insn_for (DIV, mode) ? 3 : 2;
 255 }
 256
 257 /* The default implementation of TARGET_MODE_REP_EXTENDED.  */
 258
 259 int
 260 default_mode_rep_extended (machine_mode mode ATTRIBUTE_UNUSED,
 261                            machine_mode mode_rep ATTRIBUTE_UNUSED)
 262 {
 263   return UNKNOWN;
 264 }
 265
 266 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns true.  */
 267
 268 bool
 269 hook_bool_CUMULATIVE_ARGS_true (cumulative_args_t a ATTRIBUTE_UNUSED)
 270 {
 271   return true;
 272 }
 273
 274 /* Return machine mode for non-standard suffix
 275    or VOIDmode if non-standard suffixes are unsupported.  */
 276 machine_mode
 277 default_mode_for_suffix (char suffix ATTRIBUTE_UNUSED)
 278 {
 279   return VOIDmode;
 280 }
 281
 282 /* The generic C++ ABI specifies this is a 64-bit value.  */
 283 tree
 284 default_cxx_guard_type (void)
 285 {
 286   return long_long_integer_type_node;
 287 }
 288
 289 /* Returns the size of the cookie to use when allocating an array
 290    whose elements have the indicated TYPE.  Assumes that it is already
 291    known that a cookie is needed.  */
 292
 293 tree
 294 default_cxx_get_cookie_size (tree type)
 295 {
 296   tree cookie_size;
 297
 298   /* We need to allocate an additional max (sizeof (size_t), alignof
 299      (true_type)) bytes.  */
 300   tree sizetype_size;
 301   tree type_align;
 302
 303   sizetype_size = size_in_bytes (sizetype);
 304   type_align = size_int (TYPE_ALIGN_UNIT (type));
 305   if (tree_int_cst_lt (type_align, sizetype_size))
 306     cookie_size = sizetype_size;
 307   else
 308     cookie_size = type_align;
 309
 310   return cookie_size;
 311 }
 312
 313 /* Return true if a parameter must be passed by reference.  This version
 314    of the TARGET_PASS_BY_REFERENCE hook uses just MUST_PASS_IN_STACK.  */
 315
 316 bool
 317 hook_pass_by_reference_must_pass_in_stack (cumulative_args_t c ATTRIBUTE_UNUSED,
 318         machine_mode mode ATTRIBUTE_UNUSED, const_tree type ATTRIBUTE_UNUSED,
 319         bool named_arg ATTRIBUTE_UNUSED)
 320 {
 321   return targetm.calls.must_pass_in_stack (mode, type);
 322 }
 323
 324 /* Return true if a parameter follows callee copies conventions.  This
 325    version of the hook is true for all named arguments.  */
 326
 327 bool
 328 hook_callee_copies_named (cumulative_args_t ca ATTRIBUTE_UNUSED,
 329                           machine_mode mode ATTRIBUTE_UNUSED,
 330                           const_tree type ATTRIBUTE_UNUSED, bool named)
 331 {
 332   return named;
 333 }
 334
 335 /* Emit to STREAM the assembler syntax for insn operand X.  */
 336
 337 void
 338 default_print_operand (FILE *stream ATTRIBUTE_UNUSED, rtx x ATTRIBUTE_UNUSED,
 339                        int code ATTRIBUTE_UNUSED)
 340 {
 341 #ifdef PRINT_OPERAND
 342   PRINT_OPERAND (stream, x, code);
 343 #else
 344   gcc_unreachable ();
 345 #endif
 346 }
 347
 348 /* Emit to STREAM the assembler syntax for an insn operand whose memory
 349    address is X.  */
 350
 351 void
 352 default_print_operand_address (FILE *stream ATTRIBUTE_UNUSED,
 353                                rtx x ATTRIBUTE_UNUSED)
 354 {
 355 #ifdef PRINT_OPERAND_ADDRESS
 356   PRINT_OPERAND_ADDRESS (stream, x);
 357 #else
 358   gcc_unreachable ();
 359 #endif
 360 }
 361
 362 /* Return true if CODE is a valid punctuation character for the
 363    `print_operand' hook.  */
 364
 365 bool
 366 default_print_operand_punct_valid_p (unsigned char code ATTRIBUTE_UNUSED)
 367 {
 368 #ifdef PRINT_OPERAND_PUNCT_VALID_P
 369   return PRINT_OPERAND_PUNCT_VALID_P (code);
 370 #else
 371   return false;
 372 #endif
 373 }
 374
 375 /* The default implementation of TARGET_MANGLE_ASSEMBLER_NAME.  */
 376 tree
 377 default_mangle_assembler_name (const char *name ATTRIBUTE_UNUSED)
 378 {
 379   const char *skipped = name + (*name == '*' ? 1 : 0);
 380   const char *stripped = targetm.strip_name_encoding (skipped);
 381   if (*name != '*' && user_label_prefix[0])
 382     stripped = ACONCAT ((user_label_prefix, stripped, NULL));
 383   return get_identifier (stripped);
 384 }
 385
 386 /* True if MODE is valid for the target.  By "valid", we mean able to
 387    be manipulated in non-trivial ways.  In particular, this means all
 388    the arithmetic is supported.
 389
 390    By default we guess this means that any C type is supported.  If
 391    we can't map the mode back to a type that would be available in C,
 392    then reject it.  Special case, here, is the double-word arithmetic
 393    supported by optabs.c.  */
 394
 395 bool
 396 default_scalar_mode_supported_p (machine_mode mode)
 397 {
 398   int precision = GET_MODE_PRECISION (mode);
 399
 400   switch (GET_MODE_CLASS (mode))
 401     {
 402     case MODE_PARTIAL_INT:
 403     case MODE_INT:
 404       if (precision == CHAR_TYPE_SIZE)
 405         return true;
 406       if (precision == SHORT_TYPE_SIZE)
 407         return true;
 408       if (precision == INT_TYPE_SIZE)
 409         return true;
 410       if (precision == LONG_TYPE_SIZE)
 411         return true;
 412       if (precision == LONG_LONG_TYPE_SIZE)
 413         return true;
 414       if (precision == 2 * BITS_PER_WORD)
 415         return true;
 416       return false;
 417
 418     case MODE_FLOAT:
 419       if (precision == FLOAT_TYPE_SIZE)
 420         return true;
 421       if (precision == DOUBLE_TYPE_SIZE)
 422         return true;
 423       if (precision == LONG_DOUBLE_TYPE_SIZE)
 424         return true;
 425       return false;
 426
 427     case MODE_DECIMAL_FLOAT:
 428     case MODE_FRACT:
 429     case MODE_UFRACT:
 430     case MODE_ACCUM:
 431     case MODE_UACCUM:
 432       return false;
 433
 434     default:
 435       gcc_unreachable ();
 436     }
 437 }
 438
 439 /* Return true if libgcc supports floating-point mode MODE (known to
 440    be supported as a scalar mode).  */
 441
 442 bool
 443 default_libgcc_floating_mode_supported_p (machine_mode mode)
 444 {
 445   switch (mode)
 446     {
 447 #ifdef HAVE_SFmode
 448     case SFmode:
 449 #endif
 450 #ifdef HAVE_DFmode
 451     case DFmode:
 452 #endif
 453 #ifdef HAVE_XFmode
 454     case XFmode:
 455 #endif
 456 #ifdef HAVE_TFmode
 457     case TFmode:
 458 #endif
 459       return true;
 460
 461     default:
 462       return false;
 463     }
 464 }
 465
 466 /* Make some target macros useable by target-independent code.  */
 467 bool
 468 targhook_words_big_endian (void)
 469 {
 470   return !!WORDS_BIG_ENDIAN;
 471 }
 472
 473 bool
 474 targhook_float_words_big_endian (void)
 475 {
 476   return !!FLOAT_WORDS_BIG_ENDIAN;
 477 }
 478
 479 /* True if the target supports floating-point exceptions and rounding
 480    modes.  */
 481
 482 bool
 483 default_float_exceptions_rounding_supported_p (void)
 484 {
 485 #ifdef HAVE_adddf3
 486   return HAVE_adddf3;
 487 #else
 488   return false;
 489 #endif
 490 }
 491
 492 /* True if the target supports decimal floating point.  */
 493
 494 bool
 495 default_decimal_float_supported_p (void)
 496 {
 497   return ENABLE_DECIMAL_FLOAT;
 498 }
 499
 500 /* True if the target supports fixed-point arithmetic.  */
 501
 502 bool
 503 default_fixed_point_supported_p (void)
 504 {
 505   return ENABLE_FIXED_POINT;
 506 }
 507
 508 /* True if the target supports GNU indirect functions.  */
 509
 510 bool
 511 default_has_ifunc_p (void)
 512 {
 513   return HAVE_GNU_INDIRECT_FUNCTION;
 514 }
 515
 516 /* NULL if INSN insn is valid within a low-overhead loop, otherwise returns
 517    an error message.
 518
 519    This function checks whether a given INSN is valid within a low-overhead
 520    loop.  If INSN is invalid it returns the reason for that, otherwise it
 521    returns NULL. A called function may clobber any special registers required
 522    for low-overhead looping. Additionally, some targets (eg, PPC) use the count
 523    register for branch on table instructions. We reject the doloop pattern in
 524    these cases.  */
 525
 526 const char *
 527 default_invalid_within_doloop (const rtx_insn *insn)
 528 {
 529   if (CALL_P (insn))
 530     return "Function call in loop.";
 531
 532   if (tablejump_p (insn, NULL, NULL) || computed_jump_p (insn))
 533     return "Computed branch in the loop.";
 534
 535   return NULL;
 536 }
 537
 538 /* Mapping of builtin functions to vectorized variants.  */
 539
 540 tree
 541 default_builtin_vectorized_function (tree fndecl ATTRIBUTE_UNUSED,
 542                                      tree type_out ATTRIBUTE_UNUSED,
 543                                      tree type_in ATTRIBUTE_UNUSED)
 544 {
 545   return NULL_TREE;
 546 }
 547
 548 /* Vectorized conversion.  */
 549
 550 tree
 551 default_builtin_vectorized_conversion (unsigned int code ATTRIBUTE_UNUSED,
 552                                        tree dest_type ATTRIBUTE_UNUSED,
 553                                        tree src_type ATTRIBUTE_UNUSED)
 554 {
 555   return NULL_TREE;
 556 }
 557
 558 /* Default vectorizer cost model values.  */
 559
 560 int
 561 default_builtin_vectorization_cost (enum vect_cost_for_stmt type_of_cost,
 562                                     tree vectype,
 563                                     int misalign ATTRIBUTE_UNUSED)
 564 {
 565   unsigned elements;
 566
 567   switch (type_of_cost)
 568     {
 569       case scalar_stmt:
 570       case scalar_load:
 571       case scalar_store:
 572       case vector_stmt:
 573       case vector_load:
 574       case vector_store:
 575       case vec_to_scalar:
 576       case scalar_to_vec:
 577       case cond_branch_not_taken:
 578       case vec_perm:
 579       case vec_promote_demote:
 580         return 1;
 581
 582       case unaligned_load:
 583       case unaligned_store:
 584         return 2;
 585
 586       case cond_branch_taken:
 587         return 3;
 588
 589       case vec_construct:
 590         elements = TYPE_VECTOR_SUBPARTS (vectype);
 591         return elements / 2 + 1;
 592
 593       default:
 594         gcc_unreachable ();
 595     }
 596 }
 597
 598 /* Reciprocal.  */
 599
 600 tree
 601 default_builtin_reciprocal (unsigned int fn ATTRIBUTE_UNUSED,
 602                             bool md_fn ATTRIBUTE_UNUSED,
 603                             bool sqrt ATTRIBUTE_UNUSED)
 604 {
 605   return NULL_TREE;
 606 }
 607
 608 bool
 609 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false (
 610         cumulative_args_t ca ATTRIBUTE_UNUSED,
 611         machine_mode mode ATTRIBUTE_UNUSED,
 612         const_tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
 613 {
 614   return false;
 615 }
 616
 617 bool
 618 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_true (
 619         cumulative_args_t ca ATTRIBUTE_UNUSED,
 620         machine_mode mode ATTRIBUTE_UNUSED,
 621         const_tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
 622 {
 623   return true;
 624 }
 625
 626 int
 627 hook_int_CUMULATIVE_ARGS_mode_tree_bool_0 (
 628         cumulative_args_t ca ATTRIBUTE_UNUSED,
 629         machine_mode mode ATTRIBUTE_UNUSED,
 630         tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
 631 {
 632   return 0;
 633 }
 634
 635 void
 636 default_function_arg_advance (cumulative_args_t ca ATTRIBUTE_UNUSED,
 637                               machine_mode mode ATTRIBUTE_UNUSED,
 638                               const_tree type ATTRIBUTE_UNUSED,
 639                               bool named ATTRIBUTE_UNUSED)
 640 {
 641   gcc_unreachable ();
 642 }
 643
 644 rtx
 645 default_function_arg (cumulative_args_t ca ATTRIBUTE_UNUSED,
 646                       machine_mode mode ATTRIBUTE_UNUSED,
 647                       const_tree type ATTRIBUTE_UNUSED,
 648                       bool named ATTRIBUTE_UNUSED)
 649 {
 650   gcc_unreachable ();
 651 }
 652
 653 rtx
 654 default_function_incoming_arg (cumulative_args_t ca ATTRIBUTE_UNUSED,
 655                                machine_mode mode ATTRIBUTE_UNUSED,
 656                                const_tree type ATTRIBUTE_UNUSED,
 657                                bool named ATTRIBUTE_UNUSED)
 658 {
 659   gcc_unreachable ();
 660 }
 661
 662 unsigned int
 663 default_function_arg_boundary (machine_mode mode ATTRIBUTE_UNUSED,
 664                                const_tree type ATTRIBUTE_UNUSED)
 665 {
 666   return PARM_BOUNDARY;
 667 }
 668
 669 unsigned int
 670 default_function_arg_round_boundary (machine_mode mode ATTRIBUTE_UNUSED,
 671                                      const_tree type ATTRIBUTE_UNUSED)
 672 {
 673   return PARM_BOUNDARY;
 674 }
 675
 676 void
 677 hook_void_bitmap (bitmap regs ATTRIBUTE_UNUSED)
 678 {
 679 }
 680
 681 const char *
 682 hook_invalid_arg_for_unprototyped_fn (
 683         const_tree typelist ATTRIBUTE_UNUSED,
 684         const_tree funcdecl ATTRIBUTE_UNUSED,
 685         const_tree val ATTRIBUTE_UNUSED)
 686 {
 687   return NULL;
 688 }
 689
 690 /* Initialize the stack protection decls.  */
 691
 692 /* Stack protection related decls living in libgcc.  */
 693 static GTY(()) tree stack_chk_guard_decl;
 694
 695 tree
 696 default_stack_protect_guard (void)
 697 {
 698   tree t = stack_chk_guard_decl;
 699
 700   if (t == NULL)
 701     {
 702       rtx x;
 703
 704       t = build_decl (UNKNOWN_LOCATION,
 705                       VAR_DECL, get_identifier ("__stack_chk_guard"),
 706                       ptr_type_node);
 707       TREE_STATIC (t) = 1;
 708       TREE_PUBLIC (t) = 1;
 709       DECL_EXTERNAL (t) = 1;
 710       TREE_USED (t) = 1;
 711       TREE_THIS_VOLATILE (t) = 1;
 712       DECL_ARTIFICIAL (t) = 1;
 713       DECL_IGNORED_P (t) = 1;
 714
 715       /* Do not share RTL as the declaration is visible outside of
 716          current function.  */
 717       x = DECL_RTL (t);
 718       RTX_FLAG (x, used) = 1;
 719
 720       stack_chk_guard_decl = t;
 721     }
 722
 723   return t;
 724 }
 725
 726 static GTY(()) tree stack_chk_fail_decl;
 727
 728 tree
 729 default_external_stack_protect_fail (void)
 730 {
 731   tree t = stack_chk_fail_decl;
 732
 733   if (t == NULL_TREE)
 734     {
 735       t = build_function_type_list (void_type_node, NULL_TREE);
 736       t = build_decl (UNKNOWN_LOCATION,
 737                       FUNCTION_DECL, get_identifier ("__stack_chk_fail"), t);
 738       TREE_STATIC (t) = 1;
 739       TREE_PUBLIC (t) = 1;
 740       DECL_EXTERNAL (t) = 1;
 741       TREE_USED (t) = 1;
 742       TREE_THIS_VOLATILE (t) = 1;
 743       TREE_NOTHROW (t) = 1;
 744       DECL_ARTIFICIAL (t) = 1;
 745       DECL_IGNORED_P (t) = 1;
 746       DECL_VISIBILITY (t) = VISIBILITY_DEFAULT;
 747       DECL_VISIBILITY_SPECIFIED (t) = 1;
 748
 749       stack_chk_fail_decl = t;
 750     }
 751
 752   return build_call_expr (t, 0);
 753 }
 754
 755 tree
 756 default_hidden_stack_protect_fail (void)
 757 {
 758 #ifndef HAVE_GAS_HIDDEN
 759   return default_external_stack_protect_fail ();
 760 #else
 761   tree t = stack_chk_fail_decl;
 762
 763   if (!flag_pic)
 764     return default_external_stack_protect_fail ();
 765
 766   if (t == NULL_TREE)
 767     {
 768       t = build_function_type_list (void_type_node, NULL_TREE);
 769       t = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL,
 770                       get_identifier ("__stack_chk_fail_local"), t);
 771       TREE_STATIC (t) = 1;
 772       TREE_PUBLIC (t) = 1;
 773       DECL_EXTERNAL (t) = 1;
 774       TREE_USED (t) = 1;
 775       TREE_THIS_VOLATILE (t) = 1;
 776       TREE_NOTHROW (t) = 1;
 777       DECL_ARTIFICIAL (t) = 1;
 778       DECL_IGNORED_P (t) = 1;
 779       DECL_VISIBILITY_SPECIFIED (t) = 1;
 780       DECL_VISIBILITY (t) = VISIBILITY_HIDDEN;
 781
 782       stack_chk_fail_decl = t;
 783     }
 784
 785   return build_call_expr (t, 0);
 786 #endif
 787 }
 788
 789 bool
 790 hook_bool_const_rtx_commutative_p (const_rtx x,
 791                                    int outer_code ATTRIBUTE_UNUSED)
 792 {
 793   return COMMUTATIVE_P (x);
 794 }
 795
 796 rtx
 797 default_function_value (const_tree ret_type ATTRIBUTE_UNUSED,
 798                         const_tree fn_decl_or_type,
 799                         bool outgoing ATTRIBUTE_UNUSED)
 800 {
 801   /* The old interface doesn't handle receiving the function type.  */
 802   if (fn_decl_or_type
 803       && !DECL_P (fn_decl_or_type))
 804     fn_decl_or_type = NULL;
 805
 806 #ifdef FUNCTION_VALUE
 807   return FUNCTION_VALUE (ret_type, fn_decl_or_type);
 808 #else
 809   gcc_unreachable ();
 810 #endif
 811 }
 812
 813 rtx
 814 default_libcall_value (machine_mode mode ATTRIBUTE_UNUSED,
 815                        const_rtx fun ATTRIBUTE_UNUSED)
 816 {
 817 #ifdef LIBCALL_VALUE
 818   return LIBCALL_VALUE (mode);
 819 #else
 820   gcc_unreachable ();
 821 #endif
 822 }
 823
 824 /* The default hook for TARGET_FUNCTION_VALUE_REGNO_P.  */
 825
 826 bool
 827 default_function_value_regno_p (const unsigned int regno ATTRIBUTE_UNUSED)
 828 {
 829 #ifdef FUNCTION_VALUE_REGNO_P
 830   return FUNCTION_VALUE_REGNO_P (regno);
 831 #else
 832   gcc_unreachable ();
 833 #endif
 834 }
 835
 836 rtx
 837 default_internal_arg_pointer (void)
 838 {
 839   /* If the reg that the virtual arg pointer will be translated into is
 840      not a fixed reg or is the stack pointer, make a copy of the virtual
 841      arg pointer, and address parms via the copy.  The frame pointer is
 842      considered fixed even though it is not marked as such.  */
 843   if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
 844        || ! (fixed_regs[ARG_POINTER_REGNUM]
 845              || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
 846     return copy_to_reg (virtual_incoming_args_rtx);
 847   else
 848     return virtual_incoming_args_rtx;
 849 }
 850
 851 rtx
 852 default_static_chain (const_tree ARG_UNUSED (fndecl_or_type), bool incoming_p)
 853 {
 854   if (incoming_p)
 855     {
 856 #ifdef STATIC_CHAIN_INCOMING_REGNUM
 857       return gen_rtx_REG (Pmode, STATIC_CHAIN_INCOMING_REGNUM);
 858 #endif
 859     }
 860
 861 #ifdef STATIC_CHAIN_REGNUM
 862   return gen_rtx_REG (Pmode, STATIC_CHAIN_REGNUM);
 863 #endif
 864
 865   {
 866     static bool issued_error;
 867     if (!issued_error)
 868       {
 869         issued_error = true;
 870         sorry ("nested functions not supported on this target");
 871       }
 872
 873     /* It really doesn't matter what we return here, so long at it
 874        doesn't cause the rest of the compiler to crash.  */
 875     return gen_rtx_MEM (Pmode, stack_pointer_rtx);
 876   }
 877 }
 878
 879 void
 880 default_trampoline_init (rtx ARG_UNUSED (m_tramp), tree ARG_UNUSED (t_func),
 881                          rtx ARG_UNUSED (r_chain))
 882 {
 883   sorry ("nested function trampolines not supported on this target");
 884 }
 885
 886 int
 887 default_return_pops_args (tree fundecl ATTRIBUTE_UNUSED,
 888                           tree funtype ATTRIBUTE_UNUSED,
 889                           int size ATTRIBUTE_UNUSED)
 890 {
 891   return 0;
 892 }
 893
 894 reg_class_t
 895 default_branch_target_register_class (void)
 896 {
 897   return NO_REGS;
 898 }
 899
 900 extern bool
 901 default_lra_p (void)
 902 {
 903   return false;
 904 }
 905
 906 int
 907 default_register_priority (int hard_regno ATTRIBUTE_UNUSED)
 908 {
 909   return 0;
 910 }
 911
 912 extern bool
 913 default_register_usage_leveling_p (void)
 914 {
 915   return false;
 916 }
 917
 918 extern bool
 919 default_different_addr_displacement_p (void)
 920 {
 921   return false;
 922 }
 923
 924 reg_class_t
 925 default_secondary_reload (bool in_p ATTRIBUTE_UNUSED, rtx x ATTRIBUTE_UNUSED,
 926                           reg_class_t reload_class_i ATTRIBUTE_UNUSED,
 927                           machine_mode reload_mode ATTRIBUTE_UNUSED,
 928                           secondary_reload_info *sri)
 929 {
 930   enum reg_class rclass = NO_REGS;
 931   enum reg_class reload_class = (enum reg_class) reload_class_i;
 932
 933   if (sri->prev_sri && sri->prev_sri->t_icode != CODE_FOR_nothing)
 934     {
 935       sri->icode = sri->prev_sri->t_icode;
 936       return NO_REGS;
 937     }
 938 #ifdef SECONDARY_INPUT_RELOAD_CLASS
 939   if (in_p)
 940     rclass = SECONDARY_INPUT_RELOAD_CLASS (reload_class, reload_mode, x);
 941 #endif
 942 #ifdef SECONDARY_OUTPUT_RELOAD_CLASS
 943   if (! in_p)
 944     rclass = SECONDARY_OUTPUT_RELOAD_CLASS (reload_class, reload_mode, x);
 945 #endif
 946   if (rclass != NO_REGS)
 947     {
 948       enum insn_code icode
 949         = direct_optab_handler (in_p ? reload_in_optab : reload_out_optab,
 950                                 reload_mode);
 951
 952       if (icode != CODE_FOR_nothing
 953           && !insn_operand_matches (icode, in_p, x))
 954         icode = CODE_FOR_nothing;
 955       else if (icode != CODE_FOR_nothing)
 956         {
 957           const char *insn_constraint, *scratch_constraint;
 958           enum reg_class insn_class, scratch_class;
 959
 960           gcc_assert (insn_data[(int) icode].n_operands == 3);
 961           insn_constraint = insn_data[(int) icode].operand[!in_p].constraint;
 962           if (!*insn_constraint)
 963             insn_class = ALL_REGS;
 964           else
 965             {
 966               if (in_p)
 967                 {
 968                   gcc_assert (*insn_constraint == '=');
 969                   insn_constraint++;
 970                 }
 971               insn_class = (reg_class_for_constraint
 972                             (lookup_constraint (insn_constraint)));
 973               gcc_assert (insn_class != NO_REGS);
 974             }
 975
 976           scratch_constraint = insn_data[(int) icode].operand[2].constraint;
 977           /* The scratch register's constraint must start with "=&",
 978              except for an input reload, where only "=" is necessary,
 979              and where it might be beneficial to re-use registers from
 980              the input.  */
 981           gcc_assert (scratch_constraint[0] == '='
 982                       && (in_p || scratch_constraint[1] == '&'));
 983           scratch_constraint++;
 984           if (*scratch_constraint == '&')
 985             scratch_constraint++;
 986           scratch_class = (reg_class_for_constraint
 987                            (lookup_constraint (scratch_constraint)));
 988
 989           if (reg_class_subset_p (reload_class, insn_class))
 990             {
 991               gcc_assert (scratch_class == rclass);
 992               rclass = NO_REGS;
 993             }
 994           else
 995             rclass = insn_class;
 996
 997         }
 998       if (rclass == NO_REGS)
 999         sri->icode = icode;
1000       else
1001         sri->t_icode = icode;
1002     }
1003   return rclass;
1004 }
1005
1006 /* By default, if flag_pic is true, then neither local nor global relocs
1007    should be placed in readonly memory.  */
1008
1009 int
1010 default_reloc_rw_mask (void)
1011 {
1012   return flag_pic ? 3 : 0;
1013 }
1014
1015 /* By default, do no modification. */
1016 tree default_mangle_decl_assembler_name (tree decl ATTRIBUTE_UNUSED,
1017                                          tree id)
1018 {
1019    return id;
1020 }
1021
1022 /* Default to natural alignment for vector types.  */
1023 HOST_WIDE_INT
1024 default_vector_alignment (const_tree type)
1025 {
1026   return tree_to_shwi (TYPE_SIZE (type));
1027 }
1028
1029 bool
1030 default_builtin_vector_alignment_reachable (const_tree type, bool is_packed)
1031 {
1032   if (is_packed)
1033     return false;
1034
1035   /* Assuming that types whose size is > pointer-size are not guaranteed to be
1036      naturally aligned.  */
1037   if (tree_int_cst_compare (TYPE_SIZE (type), bitsize_int (POINTER_SIZE)) > 0)
1038     return false;
1039
1040   /* Assuming that types whose size is <= pointer-size
1041      are naturally aligned.  */
1042   return true;
1043 }
1044
1045 /* By default, assume that a target supports any factor of misalignment
1046    memory access if it supports movmisalign patten.
1047    is_packed is true if the memory access is defined in a packed struct.  */
1048 bool
1049 default_builtin_support_vector_misalignment (machine_mode mode,
1050                                              const_tree type
1051                                              ATTRIBUTE_UNUSED,
1052                                              int misalignment
1053                                              ATTRIBUTE_UNUSED,
1054                                              bool is_packed
1055                                              ATTRIBUTE_UNUSED)
1056 {
1057   if (optab_handler (movmisalign_optab, mode) != CODE_FOR_nothing)
1058     return true;
1059   return false;
1060 }
1061
1062 /* By default, only attempt to parallelize bitwise operations, and
1063    possibly adds/subtracts using bit-twiddling.  */
1064
1065 machine_mode
1066 default_preferred_simd_mode (machine_mode mode ATTRIBUTE_UNUSED)
1067 {
1068   return word_mode;
1069 }
1070
1071 /* By default only the size derived from the preferred vector mode
1072    is tried.  */
1073
1074 unsigned int
1075 default_autovectorize_vector_sizes (void)
1076 {
1077   return 0;
1078 }
1079
1080 /* By default, the cost model accumulates three separate costs (prologue,
1081    loop body, and epilogue) for a vectorized loop or block.  So allocate an
1082    array of three unsigned ints, set it to zero, and return its address.  */
1083
1084 void *
1085 default_init_cost (struct loop *loop_info ATTRIBUTE_UNUSED)
1086 {
1087   unsigned *cost = XNEWVEC (unsigned, 3);
1088   cost[vect_prologue] = cost[vect_body] = cost[vect_epilogue] = 0;
1089   return cost;
1090 }
1091
1092 /* By default, the cost model looks up the cost of the given statement
1093    kind and mode, multiplies it by the occurrence count, accumulates
1094    it into the cost specified by WHERE, and returns the cost added.  */
1095
1096 unsigned
1097 default_add_stmt_cost (void *data, int count, enum vect_cost_for_stmt kind,
1098                        struct _stmt_vec_info *stmt_info, int misalign,
1099                        enum vect_cost_model_location where)
1100 {
1101   unsigned *cost = (unsigned *) data;
1102   unsigned retval = 0;
1103
1104   tree vectype = stmt_info ? stmt_vectype (stmt_info) : NULL_TREE;
1105   int stmt_cost = targetm.vectorize.builtin_vectorization_cost (kind, vectype,
1106                                                                 misalign);
1107    /* Statements in an inner loop relative to the loop being
1108       vectorized are weighted more heavily.  The value here is
1109       arbitrary and could potentially be improved with analysis.  */
1110   if (where == vect_body && stmt_info && stmt_in_inner_loop_p (stmt_info))
1111     count *= 50;  /* FIXME.  */
1112
1113   retval = (unsigned) (count * stmt_cost);
1114   cost[where] += retval;
1115
1116   return retval;
1117 }
1118
1119 /* By default, the cost model just returns the accumulated costs.  */
1120
1121 void
1122 default_finish_cost (void *data, unsigned *prologue_cost,
1123                      unsigned *body_cost, unsigned *epilogue_cost)
1124 {
1125   unsigned *cost = (unsigned *) data;
1126   *prologue_cost = cost[vect_prologue];
1127   *body_cost     = cost[vect_body];
1128   *epilogue_cost = cost[vect_epilogue];
1129 }
1130
1131 /* Free the cost data.  */
1132
1133 void
1134 default_destroy_cost_data (void *data)
1135 {
1136   free (data);
1137 }
1138
1139 /* Determine whether or not a pointer mode is valid. Assume defaults
1140    of ptr_mode or Pmode - can be overridden.  */
1141 bool
1142 default_valid_pointer_mode (machine_mode mode)
1143 {
1144   return (mode == ptr_mode || mode == Pmode);
1145 }
1146
1147 /* Determine whether the memory reference specified by REF may alias
1148    the C libraries errno location.  */
1149 bool
1150 default_ref_may_alias_errno (ao_ref *ref)
1151 {
1152   tree base = ao_ref_base (ref);
1153   /* The default implementation assumes the errno location is
1154      a declaration of type int or is always accessed via a
1155      pointer to int.  We assume that accesses to errno are
1156      not deliberately obfuscated (even in conforming ways).  */
1157   if (TYPE_UNSIGNED (TREE_TYPE (base))
1158       || TYPE_MODE (TREE_TYPE (base)) != TYPE_MODE (integer_type_node))
1159     return false;
1160   /* The default implementation assumes an errno location
1161      declaration is never defined in the current compilation unit.  */
1162   if (DECL_P (base)
1163       && !TREE_STATIC (base))
1164     return true;
1165   else if (TREE_CODE (base) == MEM_REF
1166            && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME)
1167     {
1168       struct ptr_info_def *pi = SSA_NAME_PTR_INFO (TREE_OPERAND (base, 0));
1169       return !pi || pi->pt.anything || pi->pt.nonlocal;
1170     }
1171   return false;
1172 }
1173
1174 /* Return the mode for a pointer to a given ADDRSPACE, defaulting to ptr_mode
1175    for the generic address space only.  */
1176
1177 machine_mode
1178 default_addr_space_pointer_mode (addr_space_t addrspace ATTRIBUTE_UNUSED)
1179 {
1180   gcc_assert (ADDR_SPACE_GENERIC_P (addrspace));
1181   return ptr_mode;
1182 }
1183
1184 /* Return the mode for an address in a given ADDRSPACE, defaulting to Pmode
1185    for the generic address space only.  */
1186
1187 machine_mode
1188 default_addr_space_address_mode (addr_space_t addrspace ATTRIBUTE_UNUSED)
1189 {
1190   gcc_assert (ADDR_SPACE_GENERIC_P (addrspace));
1191   return Pmode;
1192 }
1193
1194 /* Named address space version of valid_pointer_mode.  */
1195
1196 bool
1197 default_addr_space_valid_pointer_mode (machine_mode mode, addr_space_t as)
1198 {
1199   if (!ADDR_SPACE_GENERIC_P (as))
1200     return (mode == targetm.addr_space.pointer_mode (as)
1201             || mode == targetm.addr_space.address_mode (as));
1202
1203   return targetm.valid_pointer_mode (mode);
1204 }
1205
1206 /* Some places still assume that all pointer or address modes are the
1207    standard Pmode and ptr_mode.  These optimizations become invalid if
1208    the target actually supports multiple different modes.  For now,
1209    we disable such optimizations on such targets, using this function.  */
1210
1211 bool
1212 target_default_pointer_address_modes_p (void)
1213 {
1214   if (targetm.addr_space.address_mode != default_addr_space_address_mode)
1215     return false;
1216   if (targetm.addr_space.pointer_mode != default_addr_space_pointer_mode)
1217     return false;
1218
1219   return true;
1220 }
1221
1222 /* Named address space version of legitimate_address_p.  */
1223
1224 bool
1225 default_addr_space_legitimate_address_p (machine_mode mode, rtx mem,
1226                                          bool strict, addr_space_t as)
1227 {
1228   if (!ADDR_SPACE_GENERIC_P (as))
1229     gcc_unreachable ();
1230
1231   return targetm.legitimate_address_p (mode, mem, strict);
1232 }
1233
1234 /* Named address space version of LEGITIMIZE_ADDRESS.  */
1235
1236 rtx
1237 default_addr_space_legitimize_address (rtx x, rtx oldx,
1238                                        machine_mode mode, addr_space_t as)
1239 {
1240   if (!ADDR_SPACE_GENERIC_P (as))
1241     return x;
1242
1243   return targetm.legitimize_address (x, oldx, mode);
1244 }
1245
1246 /* The default hook for determining if one named address space is a subset of
1247    another and to return which address space to use as the common address
1248    space.  */
1249
1250 bool
1251 default_addr_space_subset_p (addr_space_t subset, addr_space_t superset)
1252 {
1253   return (subset == superset);
1254 }
1255
1256 /* The default hook for TARGET_ADDR_SPACE_CONVERT. This hook should never be
1257    called for targets with only a generic address space.  */
1258
1259 rtx
1260 default_addr_space_convert (rtx op ATTRIBUTE_UNUSED,
1261                             tree from_type ATTRIBUTE_UNUSED,
1262                             tree to_type ATTRIBUTE_UNUSED)
1263 {
1264   gcc_unreachable ();
1265 }
1266
1267 bool
1268 default_hard_regno_scratch_ok (unsigned int regno ATTRIBUTE_UNUSED)
1269 {
1270   return true;
1271 }
1272
1273 /* The default implementation of TARGET_MODE_DEPENDENT_ADDRESS_P.  */
1274
1275 bool
1276 default_mode_dependent_address_p (const_rtx addr ATTRIBUTE_UNUSED,
1277                                   addr_space_t addrspace ATTRIBUTE_UNUSED)
1278 {
1279   return false;
1280 }
1281
1282 bool
1283 default_target_option_valid_attribute_p (tree ARG_UNUSED (fndecl),
1284                                          tree ARG_UNUSED (name),
1285                                          tree ARG_UNUSED (args),
1286                                          int ARG_UNUSED (flags))
1287 {
1288   warning (OPT_Wattributes,
1289            "target attribute is not supported on this machine");
1290
1291   return false;
1292 }
1293
1294 bool
1295 default_target_option_pragma_parse (tree ARG_UNUSED (args),
1296                                     tree ARG_UNUSED (pop_target))
1297 {
1298   warning (OPT_Wpragmas,
1299            "#pragma GCC target is not supported for this machine");
1300
1301   return false;
1302 }
1303
1304 bool
1305 default_target_can_inline_p (tree caller, tree callee)
1306 {
1307   bool ret = false;
1308   tree callee_opts = DECL_FUNCTION_SPECIFIC_TARGET (callee);
1309   tree caller_opts = DECL_FUNCTION_SPECIFIC_TARGET (caller);
1310
1311   /* If callee has no option attributes, then it is ok to inline */
1312   if (!callee_opts)
1313     ret = true;
1314
1315   /* If caller has no option attributes, but callee does then it is not ok to
1316      inline */
1317   else if (!caller_opts)
1318     ret = false;
1319
1320   /* If both caller and callee have attributes, assume that if the
1321      pointer is different, the two functions have different target
1322      options since build_target_option_node uses a hash table for the
1323      options.  */
1324   else
1325     ret = (callee_opts == caller_opts);
1326
1327   return ret;
1328 }
1329
1330 #ifndef HAVE_casesi
1331 # define HAVE_casesi 0
1332 #endif
1333
1334 /* If the machine does not have a case insn that compares the bounds,
1335    this means extra overhead for dispatch tables, which raises the
1336    threshold for using them.  */
1337
1338 unsigned int
1339 default_case_values_threshold (void)
1340 {
1341   return (HAVE_casesi ? 4 : 5);
1342 }
1343
1344 bool
1345 default_have_conditional_execution (void)
1346 {
1347 #ifdef HAVE_conditional_execution
1348   return HAVE_conditional_execution;
1349 #else
1350   return false;
1351 #endif
1352 }
1353
1354 /* By default we assume that c99 functions are present at the runtime,
1355    but sincos is not.  */
1356 bool
1357 default_libc_has_function (enum function_class fn_class)
1358 {
1359   if (fn_class == function_c94
1360       || fn_class == function_c99_misc
1361       || fn_class == function_c99_math_complex)
1362     return true;
1363
1364   return false;
1365 }
1366
1367 bool
1368 gnu_libc_has_function (enum function_class fn_class ATTRIBUTE_UNUSED)
1369 {
1370   return true;
1371 }
1372
1373 bool
1374 no_c99_libc_has_function (enum function_class fn_class ATTRIBUTE_UNUSED)
1375 {
1376   return false;
1377 }
1378
1379 tree
1380 default_builtin_tm_load_store (tree ARG_UNUSED (type))
1381 {
1382   return NULL_TREE;
1383 }
1384
1385 /* Compute cost of moving registers to/from memory.  */
1386
1387 int
1388 default_memory_move_cost (machine_mode mode ATTRIBUTE_UNUSED,
1389                           reg_class_t rclass ATTRIBUTE_UNUSED,
1390                           bool in ATTRIBUTE_UNUSED)
1391 {
1392 #ifndef MEMORY_MOVE_COST
1393     return (4 + memory_move_secondary_cost (mode, (enum reg_class) rclass, in));
1394 #else
1395     return MEMORY_MOVE_COST (mode, (enum reg_class) rclass, in);
1396 #endif
1397 }
1398
1399 /* Compute cost of moving data from a register of class FROM to one of
1400    TO, using MODE.  */
1401
1402 int
1403 default_register_move_cost (machine_mode mode ATTRIBUTE_UNUSED,
1404                             reg_class_t from ATTRIBUTE_UNUSED,
1405                             reg_class_t to ATTRIBUTE_UNUSED)
1406 {
1407 #ifndef REGISTER_MOVE_COST
1408   return 2;
1409 #else
1410   return REGISTER_MOVE_COST (mode, (enum reg_class) from, (enum reg_class) to);
1411 #endif
1412 }
1413
1414 /* For hooks which use the MOVE_RATIO macro, this gives the legacy default
1415    behaviour.  SPEED_P is true if we are compiling for speed.  */
1416
1417 unsigned int
1418 get_move_ratio (bool speed_p ATTRIBUTE_UNUSED)
1419 {
1420   unsigned int move_ratio;
1421 #ifdef MOVE_RATIO
1422   move_ratio = (unsigned int) MOVE_RATIO (speed_p);
1423 #else
1424 #if defined (HAVE_movmemqi) || defined (HAVE_movmemhi) || defined (HAVE_movmemsi) || defined (HAVE_movmemdi) || defined (HAVE_movmemti)
1425   move_ratio = 2;
1426 #else /* No movmem patterns, pick a default.  */
1427   move_ratio = ((speed_p) ? 15 : 3);
1428 #endif
1429 #endif
1430   return move_ratio;
1431 }
1432
1433 /* Return TRUE if the move_by_pieces/set_by_pieces infrastructure should be
1434    used; return FALSE if the movmem/setmem optab should be expanded, or
1435    a call to memcpy emitted.  */
1436
1437 bool
1438 default_use_by_pieces_infrastructure_p (unsigned HOST_WIDE_INT size,
1439                                         unsigned int alignment,
1440                                         enum by_pieces_operation op,
1441                                         bool speed_p)
1442 {
1443   unsigned int max_size = 0;
1444   unsigned int ratio = 0;
1445
1446   switch (op)
1447     {
1448       case CLEAR_BY_PIECES:
1449         max_size = STORE_MAX_PIECES;
1450         ratio = CLEAR_RATIO (speed_p);
1451         break;
1452       case MOVE_BY_PIECES:
1453         max_size = MOVE_MAX_PIECES;
1454         ratio = get_move_ratio (speed_p);
1455         break;
1456       case SET_BY_PIECES:
1457         max_size = STORE_MAX_PIECES;
1458         ratio = SET_RATIO (speed_p);
1459         break;
1460       case STORE_BY_PIECES:
1461         max_size = STORE_MAX_PIECES;
1462         ratio = get_move_ratio (speed_p);
1463         break;
1464     }
1465
1466   return move_by_pieces_ninsns (size, alignment, max_size + 1) < ratio;
1467 }
1468
1469 bool
1470 default_profile_before_prologue (void)
1471 {
1472 #ifdef PROFILE_BEFORE_PROLOGUE
1473   return true;
1474 #else
1475   return false;
1476 #endif
1477 }
1478
1479 /* The default implementation of TARGET_PREFERRED_RELOAD_CLASS.  */
1480
1481 reg_class_t
1482 default_preferred_reload_class (rtx x ATTRIBUTE_UNUSED,
1483                                 reg_class_t rclass)
1484 {
1485 #ifdef PREFERRED_RELOAD_CLASS
1486   return (reg_class_t) PREFERRED_RELOAD_CLASS (x, (enum reg_class) rclass);
1487 #else
1488   return rclass;
1489 #endif
1490 }
1491
1492 /* The default implementation of TARGET_OUTPUT_PREFERRED_RELOAD_CLASS.  */
1493
1494 reg_class_t
1495 default_preferred_output_reload_class (rtx x ATTRIBUTE_UNUSED,
1496                                        reg_class_t rclass)
1497 {
1498   return rclass;
1499 }
1500
1501 /* The default implementation of TARGET_PREFERRED_RENAME_CLASS.  */
1502 reg_class_t
1503 default_preferred_rename_class (reg_class_t rclass ATTRIBUTE_UNUSED)
1504 {
1505   return NO_REGS;
1506 }
1507
1508 /* The default implementation of TARGET_CLASS_LIKELY_SPILLED_P.  */
1509
1510 bool
1511 default_class_likely_spilled_p (reg_class_t rclass)
1512 {
1513   return (reg_class_size[(int) rclass] == 1);
1514 }
1515
1516 /* The default implementation of TARGET_CLASS_MAX_NREGS.  */
1517
1518 unsigned char
1519 default_class_max_nregs (reg_class_t rclass ATTRIBUTE_UNUSED,
1520                          machine_mode mode ATTRIBUTE_UNUSED)
1521 {
1522 #ifdef CLASS_MAX_NREGS
1523   return (unsigned char) CLASS_MAX_NREGS ((enum reg_class) rclass, mode);
1524 #else
1525   return ((GET_MODE_SIZE (mode) + UNITS_PER_WORD - 1) / UNITS_PER_WORD);
1526 #endif
1527 }
1528
1529 /* Determine the debugging unwind mechanism for the target.  */
1530
1531 enum unwind_info_type
1532 default_debug_unwind_info (void)
1533 {
1534   /* If the target wants to force the use of dwarf2 unwind info, let it.  */
1535   /* ??? Change all users to the hook, then poison this.  */
1536 #ifdef DWARF2_FRAME_INFO
1537   if (DWARF2_FRAME_INFO)
1538     return UI_DWARF2;
1539 #endif
1540
1541   /* Otherwise, only turn it on if dwarf2 debugging is enabled.  */
1542 #ifdef DWARF2_DEBUGGING_INFO
1543   if (write_symbols == DWARF2_DEBUG || write_symbols == VMS_AND_DWARF2_DEBUG)
1544     return UI_DWARF2;
1545 #endif
1546
1547   return UI_NONE;
1548 }
1549
1550 /* Determine the correct mode for a Dwarf frame register that represents
1551    register REGNO.  */
1552
1553 machine_mode
1554 default_dwarf_frame_reg_mode (int regno)
1555 {
1556   machine_mode save_mode = reg_raw_mode[regno];
1557
1558   if (HARD_REGNO_CALL_PART_CLOBBERED (regno, save_mode))
1559     save_mode = choose_hard_reg_mode (regno, 1, true);
1560   return save_mode;
1561 }
1562
1563 /* To be used by targets where reg_raw_mode doesn't return the right
1564    mode for registers used in apply_builtin_return and apply_builtin_arg.  */
1565
1566 machine_mode
1567 default_get_reg_raw_mode (int regno)
1568 {
1569   return reg_raw_mode[regno];
1570 }
1571
1572 /* Return true if a leaf function should stay leaf even with profiling
1573    enabled.  */
1574
1575 bool
1576 default_keep_leaf_when_profiled ()
1577 {
1578   return false;
1579 }
1580
1581 /* Return true if the state of option OPTION should be stored in PCH files
1582    and checked by default_pch_valid_p.  Store the option's current state
1583    in STATE if so.  */
1584
1585 static inline bool
1586 option_affects_pch_p (int option, struct cl_option_state *state)
1587 {
1588   if ((cl_options[option].flags & CL_TARGET) == 0)
1589     return false;
1590   if ((cl_options[option].flags & CL_PCH_IGNORE) != 0)
1591     return false;
1592   if (option_flag_var (option, &global_options) == &target_flags)
1593     if (targetm.check_pch_target_flags)
1594       return false;
1595   return get_option_state (&global_options, option, state);
1596 }
1597
1598 /* Default version of get_pch_validity.
1599    By default, every flag difference is fatal; that will be mostly right for
1600    most targets, but completely right for very few.  */
1601
1602 void *
1603 default_get_pch_validity (size_t *sz)
1604 {
1605   struct cl_option_state state;
1606   size_t i;
1607   char *result, *r;
1608
1609   *sz = 2;
1610   if (targetm.check_pch_target_flags)
1611     *sz += sizeof (target_flags);
1612   for (i = 0; i < cl_options_count; i++)
1613     if (option_affects_pch_p (i, &state))
1614       *sz += state.size;
1615
1616   result = r = XNEWVEC (char, *sz);
1617   r[0] = flag_pic;
1618   r[1] = flag_pie;
1619   r += 2;
1620   if (targetm.check_pch_target_flags)
1621     {
1622       memcpy (r, &target_flags, sizeof (target_flags));
1623       r += sizeof (target_flags);
1624     }
1625
1626   for (i = 0; i < cl_options_count; i++)
1627     if (option_affects_pch_p (i, &state))
1628       {
1629         memcpy (r, state.data, state.size);
1630         r += state.size;
1631       }
1632
1633   return result;
1634 }
1635
1636 /* Return a message which says that a PCH file was created with a different
1637    setting of OPTION.  */
1638
1639 static const char *
1640 pch_option_mismatch (const char *option)
1641 {
1642   char *r;
1643
1644   asprintf (&r, _("created and used with differing settings of '%s'"), option);
1645   if (r == NULL)
1646     return _("out of memory");
1647   return r;
1648 }
1649
1650 /* Default version of pch_valid_p.  */
1651
1652 const char *
1653 default_pch_valid_p (const void *data_p, size_t len)
1654 {
1655   struct cl_option_state state;
1656   const char *data = (const char *)data_p;
1657   size_t i;
1658
1659   /* -fpic and -fpie also usually make a PCH invalid.  */
1660   if (data[0] != flag_pic)
1661     return _("created and used with different settings of -fpic");
1662   if (data[1] != flag_pie)
1663     return _("created and used with different settings of -fpie");
1664   data += 2;
1665
1666   /* Check target_flags.  */
1667   if (targetm.check_pch_target_flags)
1668     {
1669       int tf;
1670       const char *r;
1671
1672       memcpy (&tf, data, sizeof (target_flags));
1673       data += sizeof (target_flags);
1674       len -= sizeof (target_flags);
1675       r = targetm.check_pch_target_flags (tf);
1676       if (r != NULL)
1677         return r;
1678     }
1679
1680   for (i = 0; i < cl_options_count; i++)
1681     if (option_affects_pch_p (i, &state))
1682       {
1683         if (memcmp (data, state.data, state.size) != 0)
1684           return pch_option_mismatch (cl_options[i].opt_text);
1685         data += state.size;
1686         len -= state.size;
1687       }
1688
1689   return NULL;
1690 }
1691
1692 /* Default version of cstore_mode.  */
1693
1694 machine_mode
1695 default_cstore_mode (enum insn_code icode)
1696 {
1697   return insn_data[(int) icode].operand[0].mode;
1698 }
1699
1700 /* Default version of member_type_forces_blk.  */
1701
1702 bool
1703 default_member_type_forces_blk (const_tree, machine_mode)
1704 {
1705   return false;
1706 }
1707
1708 rtx
1709 default_load_bounds_for_arg (rtx addr ATTRIBUTE_UNUSED,
1710                              rtx ptr ATTRIBUTE_UNUSED,
1711                              rtx bnd ATTRIBUTE_UNUSED)
1712 {
1713   gcc_unreachable ();
1714 }
1715
1716 void
1717 default_store_bounds_for_arg (rtx val ATTRIBUTE_UNUSED,
1718                               rtx addr ATTRIBUTE_UNUSED,
1719                               rtx bounds ATTRIBUTE_UNUSED,
1720                               rtx to ATTRIBUTE_UNUSED)
1721 {
1722   gcc_unreachable ();
1723 }
1724
1725 rtx
1726 default_load_returned_bounds (rtx slot ATTRIBUTE_UNUSED)
1727 {
1728   gcc_unreachable ();
1729 }
1730
1731 void
1732 default_store_returned_bounds (rtx slot ATTRIBUTE_UNUSED,
1733                                rtx bounds ATTRIBUTE_UNUSED)
1734 {
1735   gcc_unreachable ();
1736 }
1737
1738 /* Default version of canonicalize_comparison.  */
1739
1740 void
1741 default_canonicalize_comparison (int *, rtx *, rtx *, bool)
1742 {
1743 }
1744
1745 /* Default implementation of TARGET_ATOMIC_ASSIGN_EXPAND_FENV.  */
1746
1747 void
1748 default_atomic_assign_expand_fenv (tree *, tree *, tree *)
1749 {
1750 }
1751
1752 #ifndef PAD_VARARGS_DOWN
1753 #define PAD_VARARGS_DOWN BYTES_BIG_ENDIAN
1754 #endif
1755
1756 /* Build an indirect-ref expression over the given TREE, which represents a
1757    piece of a va_arg() expansion.  */
1758 tree
1759 build_va_arg_indirect_ref (tree addr)
1760 {
1761   addr = build_simple_mem_ref_loc (EXPR_LOCATION (addr), addr);
1762   return addr;
1763 }
1764
1765 /* The "standard" implementation of va_arg: read the value from the
1766    current (padded) address and increment by the (padded) size.  */
1767
1768 tree
1769 std_gimplify_va_arg_expr (tree valist, tree type, gimple_seq *pre_p,
1770                           gimple_seq *post_p)
1771 {
1772   tree addr, t, type_size, rounded_size, valist_tmp;
1773   unsigned HOST_WIDE_INT align, boundary;
1774   bool indirect;
1775
1776 #ifdef ARGS_GROW_DOWNWARD
1777   /* All of the alignment and movement below is for args-grow-up machines.
1778      As of 2004, there are only 3 ARGS_GROW_DOWNWARD targets, and they all
1779      implement their own specialized gimplify_va_arg_expr routines.  */
1780   gcc_unreachable ();
1781 #endif
1782
1783   indirect = pass_by_reference (NULL, TYPE_MODE (type), type, false);
1784   if (indirect)
1785     type = build_pointer_type (type);
1786
1787   align = PARM_BOUNDARY / BITS_PER_UNIT;
1788   boundary = targetm.calls.function_arg_boundary (TYPE_MODE (type), type);
1789
1790   /* When we align parameter on stack for caller, if the parameter
1791      alignment is beyond MAX_SUPPORTED_STACK_ALIGNMENT, it will be
1792      aligned at MAX_SUPPORTED_STACK_ALIGNMENT.  We will match callee
1793      here with caller.  */
1794   if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
1795     boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
1796
1797   boundary /= BITS_PER_UNIT;
1798
1799   /* Hoist the valist value into a temporary for the moment.  */
1800   valist_tmp = get_initialized_tmp_var (valist, pre_p, NULL);
1801
1802   /* va_list pointer is aligned to PARM_BOUNDARY.  If argument actually
1803      requires greater alignment, we must perform dynamic alignment.  */
1804   if (boundary > align
1805       && !integer_zerop (TYPE_SIZE (type)))
1806     {
1807       t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist_tmp,
1808                   fold_build_pointer_plus_hwi (valist_tmp, boundary - 1));
1809       gimplify_and_add (t, pre_p);
1810
1811       t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist_tmp,
1812                   fold_build2 (BIT_AND_EXPR, TREE_TYPE (valist),
1813                                valist_tmp,
1814                                build_int_cst (TREE_TYPE (valist), -boundary)));
1815       gimplify_and_add (t, pre_p);
1816     }
1817   else
1818     boundary = align;
1819
1820   /* If the actual alignment is less than the alignment of the type,
1821      adjust the type accordingly so that we don't assume strict alignment
1822      when dereferencing the pointer.  */
1823   boundary *= BITS_PER_UNIT;
1824   if (boundary < TYPE_ALIGN (type))
1825     {
1826       type = build_variant_type_copy (type);
1827       TYPE_ALIGN (type) = boundary;
1828     }
1829
1830   /* Compute the rounded size of the type.  */
1831   type_size = size_in_bytes (type);
1832   rounded_size = round_up (type_size, align);
1833
1834   /* Reduce rounded_size so it's sharable with the postqueue.  */
1835   gimplify_expr (&rounded_size, pre_p, post_p, is_gimple_val, fb_rvalue);
1836
1837   /* Get AP.  */
1838   addr = valist_tmp;
1839   if (PAD_VARARGS_DOWN && !integer_zerop (rounded_size))
1840     {
1841       /* Small args are padded downward.  */
1842       t = fold_build2_loc (input_location, GT_EXPR, sizetype,
1843                        rounded_size, size_int (align));
1844       t = fold_build3 (COND_EXPR, sizetype, t, size_zero_node,
1845                        size_binop (MINUS_EXPR, rounded_size, type_size));
1846       addr = fold_build_pointer_plus (addr, t);
1847     }
1848
1849   /* Compute new value for AP.  */
1850   t = fold_build_pointer_plus (valist_tmp, rounded_size);
1851   t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist, t);
1852   gimplify_and_add (t, pre_p);
1853
1854   addr = fold_convert (build_pointer_type (type), addr);
1855
1856   if (indirect)
1857     addr = build_va_arg_indirect_ref (addr);
1858
1859   return build_va_arg_indirect_ref (addr);
1860 }
1861
1862 tree
1863 default_chkp_bound_type (void)
1864 {
1865   tree res = make_node (POINTER_BOUNDS_TYPE);
1866   TYPE_PRECISION (res) = TYPE_PRECISION (size_type_node) * 2;
1867   TYPE_NAME (res) = get_identifier ("__bounds_type");
1868   SET_TYPE_MODE (res, targetm.chkp_bound_mode ());
1869   layout_type (res);
1870   return res;
1871 }
1872
1873 enum machine_mode
1874 default_chkp_bound_mode (void)
1875 {
1876   return VOIDmode;
1877 }
1878
1879 tree
1880 default_builtin_chkp_function (unsigned int fcode ATTRIBUTE_UNUSED)
1881 {
1882   return NULL_TREE;
1883 }
1884
1885 rtx
1886 default_chkp_function_value_bounds (const_tree ret_type ATTRIBUTE_UNUSED,
1887                                     const_tree fn_decl_or_type ATTRIBUTE_UNUSED,
1888                                     bool outgoing ATTRIBUTE_UNUSED)
1889 {
1890   gcc_unreachable ();
1891 }
1892
1893 tree
1894 default_chkp_make_bounds_constant (HOST_WIDE_INT lb ATTRIBUTE_UNUSED,
1895                                    HOST_WIDE_INT ub ATTRIBUTE_UNUSED)
1896 {
1897   return NULL_TREE;
1898 }
1899
1900 int
1901 default_chkp_initialize_bounds (tree var ATTRIBUTE_UNUSED,
1902                                 tree lb ATTRIBUTE_UNUSED,
1903                                 tree ub ATTRIBUTE_UNUSED,
1904                                 tree *stmts ATTRIBUTE_UNUSED)
1905 {
1906   return 0;
1907 }
1908
1909 void
1910 default_setup_incoming_vararg_bounds (cumulative_args_t ca ATTRIBUTE_UNUSED,
1911                                       enum machine_mode mode ATTRIBUTE_UNUSED,
1912                                       tree type ATTRIBUTE_UNUSED,
1913                                       int *pretend_arg_size ATTRIBUTE_UNUSED,
1914                                       int second_time ATTRIBUTE_UNUSED)
1915 {
1916 }
1917
1918 /* An implementation of TARGET_CAN_USE_DOLOOP_P for targets that do
1919    not support nested low-overhead loops.  */
1920
1921 bool
1922 can_use_doloop_if_innermost (const widest_int &, const widest_int &,
1923                              unsigned int loop_depth, bool)
1924 {
1925   return loop_depth == 1;
1926 }
1927
1928 #include "gt-targhooks.h"