gcc/targhooks.c

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