gcc/target.def

   1 /* Target hook definitions.
   2    Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
   3    2011, 2012
   4    Free Software Foundation, Inc.
   5
   6    This program is free software; you can redistribute it and/or modify it
   7    under the terms of the GNU General Public License as published by the
   8    Free Software Foundation; either version 3, or (at your option) any
   9    later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; see the file COPYING3.  If not see
  18    <http://www.gnu.org/licenses/>.
  19
  20    In other words, you are welcome to use, share and improve this program.
  21    You are forbidden to forbid anyone else to use, share and improve
  22    what you give them.   Help stamp out software-hoarding!  */
  23
  24 /* See target-hooks-macros.h for details of macros that should be
  25    provided by the including file, and how to use them here.  */
  26 #include "target-hooks-macros.h"
  27
  28 #undef HOOK_TYPE
  29 #define HOOK_TYPE "Target Hook"
  30
  31 HOOK_VECTOR (TARGET_INITIALIZER, gcc_target)
  32
  33 /* Functions that output assembler for the target.  */
  34 #define HOOK_PREFIX "TARGET_ASM_"
  35 HOOK_VECTOR (TARGET_ASM_OUT, asm_out)
  36
  37 /* Opening and closing parentheses for asm expression grouping.  */
  38 DEFHOOKPOD
  39 (open_paren,
  40  "",
  41  const char *, "(")
  42 DEFHOOKPODX (close_paren, const char *, ")")
  43
  44 /* Assembler instructions for creating various kinds of integer object.  */
  45 DEFHOOKPOD
  46 (byte_op,
  47  "",
  48  const char *, "\t.byte\t")
  49 DEFHOOKPOD (aligned_op, "*", struct asm_int_op, TARGET_ASM_ALIGNED_INT_OP)
  50 DEFHOOKPOD (unaligned_op, "*", struct asm_int_op, TARGET_ASM_UNALIGNED_INT_OP)
  51
  52 /* The maximum number of bytes to skip when applying
  53    LABEL_ALIGN_AFTER_BARRIER.  */
  54 DEFHOOK
  55 (label_align_after_barrier_max_skip,
  56  "",
  57  int, (rtx label),
  58  default_label_align_after_barrier_max_skip)
  59
  60 /* The maximum number of bytes to skip when applying
  61    LOOP_ALIGN.  */
  62 DEFHOOK
  63 (loop_align_max_skip,
  64  "",
  65  int, (rtx label),
  66  default_loop_align_max_skip)
  67
  68 /* The maximum number of bytes to skip when applying
  69    LABEL_ALIGN.  */
  70 DEFHOOK
  71 (label_align_max_skip,
  72  "",
  73  int, (rtx label),
  74  default_label_align_max_skip)
  75
  76 /* The maximum number of bytes to skip when applying
  77    JUMP_ALIGN.  */
  78 DEFHOOK
  79 (jump_align_max_skip,
  80  "",
  81  int, (rtx label),
  82  default_jump_align_max_skip)
  83
  84 /* Try to output the assembler code for an integer object whose
  85    value is given by X.  SIZE is the size of the object in bytes and
  86    ALIGNED_P indicates whether it is aligned.  Return true if
  87    successful.  Only handles cases for which BYTE_OP, ALIGNED_OP
  88    and UNALIGNED_OP are NULL.  */
  89 DEFHOOK
  90 (integer,
  91  "",
  92  /* Only handles cases for which BYTE_OP, ALIGNED_OP and UNALIGNED_OP are
  93     NULL.  */
  94  bool, (rtx x, unsigned int size, int aligned_p),
  95  default_assemble_integer)
  96
  97 /* Output code that will globalize a label.  */
  98 DEFHOOK
  99 (globalize_label,
 100  "",
 101  void, (FILE *stream, const char *name),
 102  default_globalize_label)
 103
 104 /* Output code that will globalize a declaration.  */
 105 DEFHOOK
 106 (globalize_decl_name,
 107  "",
 108  void, (FILE *stream, tree decl), default_globalize_decl_name)
 109
 110 /* Output code that will emit a label for unwind info, if this
 111    target requires such labels.  Second argument is the decl the
 112    unwind info is associated with, third is a boolean: true if
 113    this is for exception handling, fourth is a boolean: true if
 114    this is only a placeholder for an omitted FDE.  */
 115 DEFHOOK
 116 (emit_unwind_label,
 117  "",
 118  void, (FILE *stream, tree decl, int for_eh, int empty),
 119  default_emit_unwind_label)
 120
 121 /* Output code that will emit a label to divide up the exception table.  */
 122 DEFHOOK
 123 (emit_except_table_label,
 124  "",
 125  void, (FILE *stream),
 126  default_emit_except_table_label)
 127
 128 /* Emit a directive for setting the personality for the function.  */
 129 DEFHOOK
 130 (emit_except_personality,
 131  "If the target implements @code{TARGET_ASM_UNWIND_EMIT}, this hook may be\
 132  used to emit a directive to install a personality hook into the unwind\
 133  info.  This hook should not be used if dwarf2 unwind info is used.",
 134  void, (rtx personality),
 135  NULL)
 136
 137 /* Emit any directives required to unwind this instruction.  */
 138 DEFHOOK
 139 (unwind_emit,
 140  "",
 141  void, (FILE *stream, rtx insn),
 142  NULL)
 143
 144 DEFHOOKPOD
 145 (unwind_emit_before_insn,
 146  "True if the @code{TARGET_ASM_UNWIND_EMIT} hook should be called before\
 147  the assembly for @var{insn} has been emitted, false if the hook should\
 148  be called afterward.",
 149  bool, true)
 150
 151 /* Generate an internal label.
 152    For now this is just a wrapper for ASM_GENERATE_INTERNAL_LABEL.  */
 153 DEFHOOK_UNDOC
 154 (generate_internal_label,
 155  "",
 156  void, (char *buf, const char *prefix, unsigned long labelno),
 157  default_generate_internal_label)
 158
 159 /* Output an internal label.  */
 160 DEFHOOK
 161 (internal_label,
 162  "",
 163  void, (FILE *stream, const char *prefix, unsigned long labelno),
 164  default_internal_label)
 165
 166 /* Output label for the constant.  */
 167 DEFHOOK
 168 (declare_constant_name,
 169  "",
 170  void, (FILE *file, const char *name, const_tree expr, HOST_WIDE_INT size),
 171  default_asm_declare_constant_name)
 172
 173 /* Emit a ttype table reference to a typeinfo object.  */
 174 DEFHOOK
 175 (ttype,
 176  "",
 177  bool, (rtx sym),
 178  hook_bool_rtx_false)
 179
 180 /* Emit an assembler directive to set visibility for the symbol
 181    associated with the tree decl.  */
 182 DEFHOOK
 183 (assemble_visibility,
 184  "",
 185  void, (tree decl, int visibility),
 186  default_assemble_visibility)
 187
 188 /* Output the assembler code for entry to a function.  */
 189 DEFHOOK
 190 (function_prologue,
 191  "",
 192  void, (FILE *file, HOST_WIDE_INT size),
 193  default_function_pro_epilogue)
 194
 195 /* Output the assembler code for end of prologue.  */
 196 DEFHOOK
 197 (function_end_prologue,
 198  "",
 199  void, (FILE *file),
 200  no_asm_to_stream)
 201
 202 /* Output the assembler code for start of epilogue.  */
 203 DEFHOOK
 204 (function_begin_epilogue,
 205  "",
 206  void, (FILE *file),
 207  no_asm_to_stream)
 208
 209 /* Output the assembler code for function exit.  */
 210 DEFHOOK
 211 (function_epilogue,
 212  "",
 213  void, (FILE *file, HOST_WIDE_INT size),
 214  default_function_pro_epilogue)
 215
 216 /* Initialize target-specific sections.  */
 217 DEFHOOK
 218 (init_sections,
 219  "",
 220  void, (void),
 221  hook_void_void)
 222
 223 /* Tell assembler to change to section NAME with attributes FLAGS.
 224    If DECL is non-NULL, it is the VAR_DECL or FUNCTION_DECL with
 225    which this section is associated.  */
 226 DEFHOOK
 227 (named_section,
 228  "",
 229  void, (const char *name, unsigned int flags, tree decl),
 230  default_no_named_section)
 231
 232 /* Return preferred text (sub)section for function DECL.
 233    Main purpose of this function is to separate cold, normal and hot
 234    functions. STARTUP is true when function is known to be used only
 235    at startup (from static constructors or it is main()).
 236    EXIT is true when function is known to be used only at exit
 237    (from static destructors).
 238    Return NULL if function should go to default text section.  */
 239 DEFHOOK
 240 (function_section,
 241  "",
 242  section *, (tree decl, enum node_frequency freq, bool startup, bool exit),
 243  default_function_section)
 244
 245 /* Output the assembler code for function exit.  */
 246 DEFHOOK
 247 (function_switched_text_sections,
 248  "Used by the target to emit any assembler directives or additional\
 249   labels needed when a function is partitioned between different\
 250   sections.  Output should be written to @var{file}.  The function\
 251   decl is available as @var{decl} and the new section is `cold' if\
 252   @var{new_is_cold} is @code{true}.",
 253  void, (FILE *file, tree decl, bool new_is_cold),
 254  default_function_switched_text_sections)
 255
 256 /* Return a mask describing how relocations should be treated when
 257    selecting sections.  Bit 1 should be set if global relocations
 258    should be placed in a read-write section; bit 0 should be set if
 259    local relocations should be placed in a read-write section.  */
 260 DEFHOOK
 261 (reloc_rw_mask,
 262  "",
 263  int, (void),
 264  default_reloc_rw_mask)
 265
 266  /* Return a section for EXP.  It may be a DECL or a constant.  RELOC
 267     is nonzero if runtime relocations must be applied; bit 1 will be
 268     set if the runtime relocations require non-local name resolution.
 269     ALIGN is the required alignment of the data.  */
 270 DEFHOOK
 271 (select_section,
 272  "",
 273  section *, (tree exp, int reloc, unsigned HOST_WIDE_INT align),
 274  default_select_section)
 275
 276 /* Return a section for X.  MODE is X's mode and ALIGN is its
 277    alignment in bits.  */
 278 DEFHOOK
 279 (select_rtx_section,
 280  "",
 281  section *, (enum machine_mode mode, rtx x, unsigned HOST_WIDE_INT align),
 282  default_select_rtx_section)
 283
 284 /* Select a unique section name for DECL.  RELOC is the same as
 285    for SELECT_SECTION.  */
 286 DEFHOOK
 287 (unique_section,
 288  "",
 289  void, (tree decl, int reloc),
 290  default_unique_section)
 291
 292 /* Return the readonly data section associated with function DECL.  */
 293 DEFHOOK
 294 (function_rodata_section,
 295  "",
 296  section *, (tree decl),
 297  default_function_rodata_section)
 298
 299 /* Nonnull if the target wants to override the default ".rodata" prefix
 300    for mergeable data sections.  */
 301 DEFHOOKPOD
 302 (mergeable_rodata_prefix,
 303  "Usually, the compiler uses the prefix @code{\".rodata\"} to construct\n\
 304 section names for mergeable constant data.  Define this macro to override\n\
 305 the string if a different section name should be used.",
 306  const char *, ".rodata")
 307
 308 /* Return the section to be used for transactional memory clone tables.  */
 309 DEFHOOK
 310 (tm_clone_table_section,
 311  "Return the section that should be used for transactional memory clone\
 312   tables.",
 313  section *, (void), default_clone_table_section)
 314
 315 /* Output a constructor for a symbol with a given priority.  */
 316 DEFHOOK
 317 (constructor,
 318  "",
 319  void, (rtx symbol, int priority), NULL)
 320
 321 /* Output a destructor for a symbol with a given priority.  */
 322 DEFHOOK
 323 (destructor,
 324  "",
 325  void, (rtx symbol, int priority), NULL)
 326
 327 /* Output the assembler code for a thunk function.  THUNK_DECL is the
 328    declaration for the thunk function itself, FUNCTION is the decl for
 329    the target function.  DELTA is an immediate constant offset to be
 330    added to THIS.  If VCALL_OFFSET is nonzero, the word at
 331    *(*this + vcall_offset) should be added to THIS.  */
 332 DEFHOOK
 333 (output_mi_thunk,
 334  "",
 335  void, (FILE *file, tree thunk_fndecl, HOST_WIDE_INT delta,
 336         HOST_WIDE_INT vcall_offset, tree function),
 337  NULL)
 338
 339 /* Determine whether output_mi_thunk would succeed.  */
 340 /* ??? Ideally, this hook would not exist, and success or failure
 341    would be returned from output_mi_thunk directly.  But there's
 342    too much undo-able setup involved in invoking output_mi_thunk.
 343    Could be fixed by making output_mi_thunk emit rtl instead of
 344    text to the output file.  */
 345 DEFHOOK
 346 (can_output_mi_thunk,
 347  "",
 348  bool, (const_tree thunk_fndecl, HOST_WIDE_INT delta,
 349         HOST_WIDE_INT vcall_offset, const_tree function),
 350  hook_bool_const_tree_hwi_hwi_const_tree_false)
 351
 352 /* Output any boilerplate text needed at the beginning of a
 353    translation unit.  */
 354 DEFHOOK
 355 (file_start,
 356  "",
 357  void, (void),
 358  default_file_start)
 359
 360 /* Output any boilerplate text needed at the end of a translation unit.  */
 361 DEFHOOK
 362 (file_end,
 363  "",
 364  void, (void),
 365  hook_void_void)
 366
 367 /* Output any boilerplate text needed at the beginning of an
 368    LTO output stream.  */
 369 DEFHOOK
 370 (lto_start,
 371  "",
 372  void, (void),
 373  hook_void_void)
 374
 375 /* Output any boilerplate text needed at the end of an
 376    LTO output stream.  */
 377 DEFHOOK
 378 (lto_end,
 379  "",
 380  void, (void),
 381  hook_void_void)
 382
 383 /* Output any boilerplace text needed at the end of a
 384    translation unit before debug and unwind info is emitted.  */
 385 DEFHOOK
 386 (code_end,
 387  "",
 388  void, (void),
 389  hook_void_void)
 390
 391 /* Output an assembler pseudo-op to declare a library function name
 392    external.  */
 393 DEFHOOK
 394 (external_libcall,
 395  "",
 396  void, (rtx symref),
 397  default_external_libcall)
 398
 399 /* Output an assembler directive to mark decl live. This instructs
 400    linker to not dead code strip this symbol.  */
 401 DEFHOOK
 402 (mark_decl_preserved,
 403  "",
 404  void, (const char *symbol),
 405  hook_void_constcharptr)
 406
 407 /* Output a record of the command line switches that have been passed.  */
 408 DEFHOOK
 409 (record_gcc_switches,
 410  "",
 411  int, (print_switch_type type, const char *text),
 412  NULL)
 413
 414 /* The name of the section that the example ELF implementation of
 415    record_gcc_switches will use to store the information.  Target
 416    specific versions of record_gcc_switches may or may not use
 417    this information.  */
 418 DEFHOOKPOD
 419 (record_gcc_switches_section,
 420  "",
 421  const char *, ".GCC.command.line")
 422
 423 /* Output the definition of a section anchor.  */
 424 DEFHOOK
 425 (output_anchor,
 426  "",
 427  void, (rtx x),
 428  default_asm_output_anchor)
 429
 430 DEFHOOK
 431 (output_ident,
 432  "Output a string based on @var{name}, suitable for the @samp{#ident} \
 433  directive, or the equivalent directive or pragma in non-C-family languages. \
 434  If this hook is not defined, nothing is output for the @samp{#ident} \
 435  directive.",
 436  void, (const char *name),
 437  hook_void_constcharptr)
 438
 439 /* Output a DTP-relative reference to a TLS symbol.  */
 440 DEFHOOK
 441 (output_dwarf_dtprel,
 442  "",
 443  void, (FILE *file, int size, rtx x),
 444  NULL)
 445
 446 /* Some target machines need to postscan each insn after it is output.  */
 447 DEFHOOK
 448 (final_postscan_insn,
 449  "",
 450  void, (FILE *file, rtx insn, rtx *opvec, int noperands),
 451  NULL)
 452
 453 /* Emit the trampoline template.  This hook may be NULL.  */
 454 DEFHOOK
 455 (trampoline_template,
 456  "",
 457  void, (FILE *f),
 458  NULL)
 459
 460 DEFHOOK
 461 (output_source_filename,
 462  "Output COFF information or DWARF debugging information which indicates\
 463  that filename @var{name} is the current source file to the stdio\
 464  stream @var{file}.\n\
 465  \n\
 466  This target hook need not be defined if the standard form of output\
 467  for the file format in use is appropriate.",
 468  void ,(FILE *file, const char *name),
 469  default_asm_output_source_filename)
 470
 471 DEFHOOK
 472 (output_addr_const_extra,
 473  "",
 474  bool, (FILE *file, rtx x),
 475  hook_bool_FILEptr_rtx_false)
 476
 477 /* ??? The TARGET_PRINT_OPERAND* hooks are part of the asm_out struct,
 478    even though that is not reflected in the macro name to override their
 479    initializers.  */
 480 #undef HOOK_PREFIX
 481 #define HOOK_PREFIX "TARGET_"
 482
 483 /* Emit a machine-specific insn operand.  */
 484 /* ??? tm.texi only documents the old macro PRINT_OPERAND,
 485    not this  hook, and uses a different name for the argument FILE.  */
 486 DEFHOOK_UNDOC
 487 (print_operand,
 488  "",
 489  void, (FILE *file, rtx x, int code),
 490  default_print_operand)
 491
 492 /* Emit a machine-specific memory address.  */
 493 /* ??? tm.texi only documents the old macro PRINT_OPERAND_ADDRESS,
 494    not this  hook, and uses different argument names.  */
 495 DEFHOOK_UNDOC
 496 (print_operand_address,
 497  "",
 498  void, (FILE *file, rtx addr),
 499  default_print_operand_address)
 500
 501 /* Determine whether CODE is a valid punctuation character for the
 502    `print_operand' hook.  */
 503 /* ??? tm.texi only documents the old macro PRINT_OPERAND_PUNCT_VALID_P,
 504    not this  hook.  */
 505 DEFHOOK_UNDOC
 506 (print_operand_punct_valid_p,
 507  "",
 508  bool ,(unsigned char code),
 509  default_print_operand_punct_valid_p)
 510
 511 /* Given a symbol name, perform same mangling as assemble_name and
 512    ASM_OUTPUT_LABELREF, returning result as an IDENTIFIER_NODE.  */
 513 DEFHOOK
 514 (mangle_assembler_name,
 515  "Given a symbol @var{name}, perform same mangling as @code{varasm.c}'s\
 516  @code{assemble_name}, but in memory rather than to a file stream, returning\
 517  result as an @code{IDENTIFIER_NODE}.  Required for correct LTO symtabs.  The\
 518  default implementation calls the @code{TARGET_STRIP_NAME_ENCODING} hook and\
 519  then prepends the @code{USER_LABEL_PREFIX}, if any.",
 520  tree, (const char *name),
 521  default_mangle_assembler_name)
 522
 523 HOOK_VECTOR_END (asm_out)
 524
 525 /* Functions relating to instruction scheduling.  All of these
 526    default to null pointers, which haifa-sched.c looks for and handles.  */
 527 #undef HOOK_PREFIX
 528 #define HOOK_PREFIX "TARGET_SCHED_"
 529 HOOK_VECTOR (TARGET_SCHED, sched)
 530
 531 /* Given the current cost, COST, of an insn, INSN, calculate and
 532    return a new cost based on its relationship to DEP_INSN through
 533    the dependence LINK.  The default is to make no adjustment.  */
 534 DEFHOOK
 535 (adjust_cost,
 536  "",
 537  int, (rtx insn, rtx link, rtx dep_insn, int cost), NULL)
 538
 539 /* Adjust the priority of an insn as you see fit.  Returns the new priority.  */
 540 DEFHOOK
 541 (adjust_priority,
 542  "",
 543  int, (rtx insn, int priority), NULL)
 544
 545 /* Function which returns the maximum number of insns that can be
 546    scheduled in the same machine cycle.  This must be constant
 547    over an entire compilation.  The default is 1.  */
 548 DEFHOOK
 549 (issue_rate,
 550  "",
 551  int, (void), NULL)
 552
 553 /* Calculate how much this insn affects how many more insns we
 554    can emit this cycle.  Default is they all cost the same.  */
 555 DEFHOOK
 556 (variable_issue,
 557  "",
 558  int, (FILE *file, int verbose, rtx insn, int more), NULL)
 559
 560 /* Initialize machine-dependent scheduling code.  */
 561 DEFHOOK
 562 (init,
 563  "",
 564  void, (FILE *file, int verbose, int max_ready), NULL)
 565
 566 /* Finalize machine-dependent scheduling code.  */
 567 DEFHOOK
 568 (finish,
 569  "",
 570  void, (FILE *file, int verbose), NULL)
 571
 572  /* Initialize machine-dependent function wide scheduling code.  */
 573 DEFHOOK
 574 (init_global,
 575  "",
 576  void, (FILE *file, int verbose, int old_max_uid), NULL)
 577
 578 /* Finalize machine-dependent function wide scheduling code.  */
 579 DEFHOOK
 580 (finish_global,
 581  "",
 582  void, (FILE *file, int verbose), NULL)
 583
 584 /* Reorder insns in a machine-dependent fashion, in two different
 585        places.  Default does nothing.  */
 586 DEFHOOK
 587 (reorder,
 588  "",
 589  int, (FILE *file, int verbose, rtx *ready, int *n_readyp, int clock), NULL)
 590
 591 DEFHOOK
 592 (reorder2,
 593  "",
 594  int, (FILE *file, int verbose, rtx *ready, int *n_readyp, int clock), NULL)
 595
 596 /* The following member value is a pointer to a function called
 597    after evaluation forward dependencies of insns in chain given
 598    by two parameter values (head and tail correspondingly).  */
 599 DEFHOOK
 600 (dependencies_evaluation_hook,
 601  "",
 602  void, (rtx head, rtx tail), NULL)
 603
 604 /* The values of the following four members are pointers to functions
 605    used to simplify the automaton descriptions.  dfa_pre_cycle_insn and
 606    dfa_post_cycle_insn give functions returning insns which are used to
 607    change the pipeline hazard recognizer state when the new simulated
 608    processor cycle correspondingly starts and finishes.  The function
 609    defined by init_dfa_pre_cycle_insn and init_dfa_post_cycle_insn are
 610    used to initialize the corresponding insns.  The default values of
 611    the members result in not changing the automaton state when the
 612    new simulated processor cycle correspondingly starts and finishes.  */
 613
 614 DEFHOOK
 615 (init_dfa_pre_cycle_insn,
 616  "",
 617  void, (void), NULL)
 618
 619 DEFHOOK
 620 (dfa_pre_cycle_insn,
 621  "",
 622  rtx, (void), NULL)
 623
 624 DEFHOOK
 625 (init_dfa_post_cycle_insn,
 626  "",
 627  void, (void), NULL)
 628
 629 DEFHOOK
 630 (dfa_post_cycle_insn,
 631  "",
 632  rtx, (void), NULL)
 633
 634 /* The values of the following two members are pointers to
 635    functions used to simplify the automaton descriptions.
 636    dfa_pre_advance_cycle and dfa_post_advance_cycle are getting called
 637    immediately before and after cycle is advanced.  */
 638
 639 DEFHOOK
 640 (dfa_pre_advance_cycle,
 641  "",
 642  void, (void), NULL)
 643
 644 DEFHOOK
 645 (dfa_post_advance_cycle,
 646  "",
 647  void, (void), NULL)
 648
 649 /* The following member value is a pointer to a function returning value
 650    which defines how many insns in queue `ready' will we try for
 651    multi-pass scheduling.  If the member value is nonzero and the
 652    function returns positive value, the DFA based scheduler will make
 653    multi-pass scheduling for the first cycle.  In other words, we will
 654    try to choose ready insn which permits to start maximum number of
 655    insns on the same cycle.  */
 656 DEFHOOK
 657 (first_cycle_multipass_dfa_lookahead,
 658  "",
 659  int, (void), NULL)
 660
 661 /* The following member value is pointer to a function controlling
 662    what insns from the ready insn queue will be considered for the
 663    multipass insn scheduling.  If the hook returns zero for insn
 664    passed as the parameter, the insn will be not chosen to be issued.  */
 665 DEFHOOK
 666 (first_cycle_multipass_dfa_lookahead_guard,
 667  "",
 668  int, (rtx insn), NULL)
 669
 670 /* This hook prepares the target for a new round of multipass
 671    scheduling.
 672    DATA is a pointer to target-specific data used for multipass scheduling.
 673    READY_TRY and N_READY represent the current state of search in the
 674    optimization space.  The target can filter out instructions that
 675    should not be tried during current round by setting corresponding
 676    elements in READY_TRY to non-zero.
 677    FIRST_CYCLE_INSN_P is true if this is the first round of multipass
 678    scheduling on current cycle.  */
 679 DEFHOOK
 680 (first_cycle_multipass_begin,
 681  "",
 682  void, (void *data, char *ready_try, int n_ready, bool first_cycle_insn_p),
 683  NULL)
 684
 685 /* This hook is called when multipass scheduling evaluates instruction INSN.
 686    DATA is a pointer to target-specific data that can be used to record effects
 687    of INSN on CPU that are not described in DFA.
 688    READY_TRY and N_READY represent the current state of search in the
 689    optimization space.  The target can filter out instructions that
 690    should not be tried after issuing INSN by setting corresponding
 691    elements in READY_TRY to non-zero.
 692    INSN is the instruction being evaluated.
 693    PREV_DATA is a pointer to target-specific data corresponding
 694    to a state before issuing INSN.  */
 695 DEFHOOK
 696 (first_cycle_multipass_issue,
 697  "",
 698  void, (void *data, char *ready_try, int n_ready, rtx insn,
 699         const void *prev_data), NULL)
 700
 701 /* This hook is called when multipass scheduling backtracks from evaluation of
 702    instruction corresponding to DATA.
 703    DATA is a pointer to target-specific data that stores the effects
 704    of instruction from which the algorithm backtracks on CPU that are not
 705    described in DFA.
 706    READY_TRY and N_READY represent the current state of search in the
 707    optimization space.  The target can filter out instructions that
 708    should not be tried after issuing INSN by setting corresponding
 709    elements in READY_TRY to non-zero.  */
 710 DEFHOOK
 711 (first_cycle_multipass_backtrack,
 712  "",
 713  void, (const void *data, char *ready_try, int n_ready), NULL)
 714
 715 /* This hook notifies the target about the result of the concluded current
 716    round of multipass scheduling.
 717    DATA is a pointer.
 718    If DATA is non-NULL it points to target-specific data used for multipass
 719    scheduling which corresponds to instruction at the start of the chain of
 720    the winning solution.  DATA is NULL when multipass scheduling cannot find
 721    a good enough solution on current cycle and decides to retry later,
 722    usually after advancing the cycle count.  */
 723 DEFHOOK
 724 (first_cycle_multipass_end,
 725  "",
 726  void, (const void *data), NULL)
 727
 728 /* This hook is called to initialize target-specific data for multipass
 729    scheduling after it has been allocated.
 730    DATA is a pointer to target-specific data that stores the effects
 731    of instruction from which the algorithm backtracks on CPU that are not
 732    described in DFA.  */
 733 DEFHOOK
 734 (first_cycle_multipass_init,
 735  "",
 736  void, (void *data), NULL)
 737
 738 /* This hook is called to finalize target-specific data for multipass
 739    scheduling before it is deallocated.
 740    DATA is a pointer to target-specific data that stores the effects
 741    of instruction from which the algorithm backtracks on CPU that are not
 742    described in DFA.  */
 743 DEFHOOK
 744 (first_cycle_multipass_fini,
 745  "",
 746  void, (void *data), NULL)
 747
 748 /* The following member value is pointer to a function called by
 749    the insn scheduler before issuing insn passed as the third
 750    parameter on given cycle.  If the hook returns nonzero, the
 751    insn is not issued on given processors cycle.  Instead of that,
 752    the processor cycle is advanced.  If the value passed through
 753    the last parameter is zero, the insn ready queue is not sorted
 754    on the new cycle start as usually.  The first parameter passes
 755    file for debugging output.  The second one passes the scheduler
 756    verbose level of the debugging output.  The forth and the fifth
 757    parameter values are correspondingly processor cycle on which
 758    the previous insn has been issued and the current processor cycle.  */
 759 DEFHOOK
 760 (dfa_new_cycle,
 761  "",
 762  int, (FILE *dump, int verbose, rtx insn, int last_clock,
 763        int clock, int *sort_p),
 764  NULL)
 765
 766 /* The following member value is a pointer to a function called by the
 767    insn scheduler.  It should return true if there exists a dependence
 768    which is considered costly by the target, between the insn
 769    DEP_PRO (&_DEP), and the insn DEP_CON (&_DEP).  The first parameter is
 770    the dep that represents the dependence between the two insns.  The
 771    second argument is the cost of the dependence as estimated by
 772    the scheduler.  The last argument is the distance in cycles
 773    between the already scheduled insn (first parameter) and the
 774    second insn (second parameter).  */
 775 DEFHOOK
 776 (is_costly_dependence,
 777  "",
 778  bool, (struct _dep *_dep, int cost, int distance), NULL)
 779
 780 DEFHOOK_UNDOC
 781 (adjust_cost_2,
 782  "Given the current cost, @var{cost}, of an insn, @var{insn}, calculate and\
 783  return a new cost based on its relationship to @var{dep_insn} through the\
 784  dependence of weakness @var{dw}.  The default is to make no adjustment.",
 785  int, (rtx insn, int dep_type1, rtx dep_insn, int cost, int dw), NULL)
 786
 787 /* The following member value is a pointer to a function called
 788    by the insn scheduler. This hook is called to notify the backend
 789    that new instructions were emitted.  */
 790 DEFHOOK
 791 (h_i_d_extended,
 792  "",
 793  void, (void), NULL)
 794
 795 /* Next 5 functions are for multi-point scheduling.  */
 796
 797 /* Allocate memory for scheduler context.  */
 798 DEFHOOK
 799 (alloc_sched_context,
 800  "",
 801  void *, (void), NULL)
 802
 803 /* Fills the context from the local machine scheduler context.  */
 804 DEFHOOK
 805 (init_sched_context,
 806  "",
 807  void, (void *tc, bool clean_p), NULL)
 808
 809 /* Sets local machine scheduler context to a saved value.  */
 810 DEFHOOK
 811 (set_sched_context,
 812  "",
 813  void, (void *tc), NULL)
 814
 815 /* Clears a scheduler context so it becomes like after init.  */
 816 DEFHOOK
 817 (clear_sched_context,
 818  "",
 819  void, (void *tc), NULL)
 820
 821 /* Frees the scheduler context.  */
 822 DEFHOOK
 823 (free_sched_context,
 824  "",
 825  void, (void *tc), NULL)
 826
 827 /* The following member value is a pointer to a function called
 828    by the insn scheduler.
 829    The first parameter is an instruction, the second parameter is the type
 830    of the requested speculation, and the third parameter is a pointer to the
 831    speculative pattern of the corresponding type (set if return value == 1).
 832    It should return
 833    -1, if there is no pattern, that will satisfy the requested speculation type,
 834    0, if current pattern satisfies the requested speculation type,
 835    1, if pattern of the instruction should be changed to the newly
 836    generated one.  */
 837 DEFHOOK
 838 (speculate_insn,
 839  "",
 840  int, (rtx insn, int request, rtx *new_pat), NULL)
 841
 842 /* The following member value is a pointer to a function called
 843    by the insn scheduler.  It should return true if the check instruction
 844    passed as the parameter needs a recovery block.  */
 845 DEFHOOK
 846 (needs_block_p,
 847  "",
 848  bool, (int dep_status), NULL)
 849
 850 /* The following member value is a pointer to a function called
 851    by the insn scheduler.  It should return a pattern for the check
 852    instruction.
 853    The first parameter is a speculative instruction, the second parameter
 854    is the label of the corresponding recovery block (or null, if it is a
 855    simple check).  If the mutation of the check is requested (e.g. from
 856    ld.c to chk.a), the third parameter is true - in this case the first
 857    parameter is the previous check.  */
 858 DEFHOOK
 859 (gen_spec_check,
 860  "",
 861  rtx, (rtx insn, rtx label, int mutate_p), NULL)
 862
 863 /* The following member value is a pointer to a function controlling
 864    what insns from the ready insn queue will be considered for the
 865    multipass insn scheduling.  If the hook returns zero for the insn
 866    passed as the parameter, the insn will not be chosen to be
 867    issued.  This hook is used to discard speculative instructions,
 868    that stand at the first position of the ready list.  */
 869 DEFHOOK
 870 (first_cycle_multipass_dfa_lookahead_guard_spec,
 871  "",
 872  bool, (const_rtx insn), NULL)
 873
 874 /* The following member value is a pointer to a function that provides
 875    information about the speculation capabilities of the target.
 876    The parameter is a pointer to spec_info variable.  */
 877 DEFHOOK
 878 (set_sched_flags,
 879  "",
 880  void, (struct spec_info_def *spec_info), NULL)
 881
 882 DEFHOOK_UNDOC
 883 (get_insn_spec_ds,
 884  "Return speculation types of instruction @var{insn}.",
 885  int, (rtx insn), NULL)
 886
 887 DEFHOOK_UNDOC
 888 (get_insn_checked_ds,
 889  "Return speculation types that are checked for instruction @var{insn}",
 890  int, (rtx insn), NULL)
 891
 892 DEFHOOK_UNDOC
 893 (skip_rtx_p,
 894  "Return bool if rtx scanning should just skip current layer and\
 895  advance to the inner rtxes.",
 896  bool, (const_rtx x), NULL)
 897
 898 /* The following member value is a pointer to a function that provides
 899    information about the target resource-based lower bound which is
 900    used by the swing modulo scheduler.  The parameter is a pointer
 901    to ddg variable.  */
 902 DEFHOOK
 903 (sms_res_mii,
 904  "",
 905  int, (struct ddg *g), NULL)
 906
 907 /* The following member value is a function that initializes dispatch
 908    schedling and adds instructions to dispatch window according to its
 909    parameters.  */
 910 DEFHOOK
 911 (dispatch_do,
 912 "",
 913 void, (rtx insn, int x),
 914 hook_void_rtx_int)
 915
 916 /* The following member value is a a function that returns true is
 917    dispatch schedling is supported in hardware and condition passed
 918    as the second parameter is true.  */
 919 DEFHOOK
 920 (dispatch,
 921 "",
 922 bool, (rtx insn, int x),
 923 hook_bool_rtx_int_false)
 924
 925 DEFHOOKPOD
 926 (exposed_pipeline,
 927 "True if the processor has an exposed pipeline, which means that not just\n\
 928 the order of instructions is important for correctness when scheduling, but\n\
 929 also the latencies of operations.",
 930 bool, false)
 931
 932 /* The following member value is a function that returns number
 933    of operations reassociator should try to put in parallel for
 934    statements of the given type.  By default 1 is used.  */
 935 DEFHOOK
 936 (reassociation_width,
 937 "This hook is called by tree reassociator to determine a level of\n\
 938 parallelism required in output calculations chain.",
 939 int, (unsigned int opc, enum machine_mode mode),
 940 hook_int_uint_mode_1)
 941
 942 HOOK_VECTOR_END (sched)
 943
 944 /* Functions relating to vectorization.  */
 945 #undef HOOK_PREFIX
 946 #define HOOK_PREFIX "TARGET_VECTORIZE_"
 947 HOOK_VECTOR (TARGET_VECTORIZE, vectorize)
 948
 949 /* The following member value is a pointer to a function called
 950    by the vectorizer, and return the decl of the target builtin
 951    function.  */
 952 DEFHOOK
 953 (builtin_mask_for_load,
 954  "",
 955  tree, (void), NULL)
 956
 957 /* Returns a code for builtin that realizes vectorized version of
 958    function, or NULL_TREE if not available.  */
 959 DEFHOOK
 960 (builtin_vectorized_function,
 961  "",
 962  tree, (tree fndecl, tree vec_type_out, tree vec_type_in),
 963  default_builtin_vectorized_function)
 964
 965 /* Returns a function declaration for a builtin that realizes the
 966    vector conversion, or NULL_TREE if not available.  */
 967 DEFHOOK
 968 (builtin_conversion,
 969  "",
 970  tree, (unsigned code, tree dest_type, tree src_type),
 971  default_builtin_vectorized_conversion)
 972
 973 /* Cost of different vector/scalar statements in vectorization cost
 974    model. In case of misaligned vector loads and stores the cost depends
 975    on the data type and misalignment value.  */
 976 DEFHOOK
 977 (builtin_vectorization_cost,
 978  "",
 979  int, (enum vect_cost_for_stmt type_of_cost, tree vectype, int misalign),
 980  default_builtin_vectorization_cost)
 981
 982 /* Return true if vector alignment is reachable (by peeling N
 983    iterations) for the given type.  */
 984 DEFHOOK
 985 (vector_alignment_reachable,
 986  "",
 987  bool, (const_tree type, bool is_packed),
 988  default_builtin_vector_alignment_reachable)
 989
 990 /* Return true if a vector created for vec_perm_const is valid.
 991    A NULL indicates that all constants are valid permutations.  */
 992 DEFHOOK
 993 (vec_perm_const_ok,
 994  "",
 995  bool, (enum machine_mode, const unsigned char *sel),
 996  NULL)
 997
 998 /* Return true if the target supports misaligned store/load of a
 999    specific factor denoted in the third parameter.  The last parameter
1000    is true if the access is defined in a packed struct.  */
1001 DEFHOOK
1002 (support_vector_misalignment,
1003  "",
1004  bool,
1005  (enum machine_mode mode, const_tree type, int misalignment, bool is_packed),
1006  default_builtin_support_vector_misalignment)
1007
1008 /* Return the builtin decl needed to load a vector of TYPE.  */
1009 DEFHOOK
1010 (builtin_tm_load,
1011  "This hook should return the built-in decl needed to load a vector of the "
1012  "given type within a transaction.",
1013  tree,
1014  (tree),
1015  default_builtin_tm_load_store)
1016
1017 /* Return the builtin decl needed to store a vector of TYPE.  */
1018 DEFHOOK
1019 (builtin_tm_store,
1020  "This hook should return the built-in decl needed to store a vector of the "
1021  "given type within a transaction.",
1022  tree,
1023  (tree),
1024  default_builtin_tm_load_store)
1025
1026 /* Returns the preferred mode for SIMD operations for the specified
1027    scalar mode.  */
1028 DEFHOOK
1029 (preferred_simd_mode,
1030  "",
1031  enum machine_mode,
1032  (enum machine_mode mode),
1033  default_preferred_simd_mode)
1034
1035 /* Returns a mask of vector sizes to iterate over when auto-vectorizing
1036    after processing the preferred one derived from preferred_simd_mode.  */
1037 DEFHOOK
1038 (autovectorize_vector_sizes,
1039  "",
1040  unsigned int,
1041  (void),
1042  default_autovectorize_vector_sizes)
1043
1044 /* Target builtin that implements vector gather operation.  */
1045 DEFHOOK
1046 (builtin_gather,
1047  "",
1048  tree,
1049  (const_tree mem_vectype, const_tree index_type, int scale),
1050  NULL)
1051
1052 /* Target function to initialize the cost model for a loop or block.  */
1053 DEFHOOK
1054 (init_cost,
1055  "This hook should initialize target-specific data structures in preparation "
1056  "for modeling the costs of vectorizing a loop or basic block.  The default "
1057  "allocates three unsigned integers for accumulating costs for the prologue, "
1058  "body, and epilogue of the loop or basic block.  If @var{loop_info} is "
1059  "non-NULL, it identifies the loop being vectorized; otherwise a single block "
1060  "is being vectorized.",
1061  void *,
1062  (struct loop *loop_info),
1063  default_init_cost)
1064
1065 /* Target function to record N statements of the given kind using the
1066    given vector type within the cost model data for the current loop or
1067     block.  */
1068 DEFHOOK
1069 (add_stmt_cost,
1070  "This hook should update the target-specific @var{data} in response to "
1071  "adding @var{count} copies of the given @var{kind} of statement to a "
1072  "loop or basic block.  The default adds the builtin vectorizer cost for "
1073  "the copies of the statement to the accumulator specified by @var{where}, "
1074  "(the prologue, body, or epilogue) and returns the amount added.  The "
1075  "return value should be viewed as a tentative cost that may later be "
1076  "revised.",
1077  unsigned,
1078  (void *data, int count, enum vect_cost_for_stmt kind,
1079   struct _stmt_vec_info *stmt_info, int misalign,
1080   enum vect_cost_model_location where),
1081  default_add_stmt_cost)
1082
1083 /* Target function to calculate the total cost of the current vectorized
1084    loop or block.  */
1085 DEFHOOK
1086 (finish_cost,
1087  "This hook should complete calculations of the cost of vectorizing a loop "
1088  "or basic block based on @var{data}, and return the prologue, body, and "
1089  "epilogue costs as unsigned integers.  The default returns the value of "
1090  "the three accumulators.",
1091  void,
1092  (void *data, unsigned *prologue_cost, unsigned *body_cost,
1093   unsigned *epilogue_cost),
1094  default_finish_cost)
1095
1096 /* Function to delete target-specific cost modeling data.  */
1097 DEFHOOK
1098 (destroy_cost_data,
1099  "This hook should release @var{data} and any related data structures "
1100  "allocated by TARGET_VECTORIZE_INIT_COST.  The default releases the "
1101  "accumulator.",
1102  void,
1103  (void *data),
1104  default_destroy_cost_data)
1105
1106 HOOK_VECTOR_END (vectorize)
1107
1108 #undef HOOK_PREFIX
1109 #define HOOK_PREFIX "TARGET_"
1110
1111 /* Allow target specific overriding of option settings after options have
1112   been changed by an attribute or pragma or when it is reset at the
1113   end of the code affected by an attribute or pragma.  */
1114 DEFHOOK
1115 (override_options_after_change,
1116  "",
1117  void, (void),
1118  hook_void_void)
1119
1120 DEFHOOK_UNDOC
1121 (eh_return_filter_mode,
1122  "Return machine mode for filter value.",
1123  enum machine_mode, (void),
1124  default_eh_return_filter_mode)
1125
1126 /* Return machine mode for libgcc expanded cmp instructions.  */
1127 DEFHOOK
1128 (libgcc_cmp_return_mode,
1129  "",
1130  enum machine_mode, (void),
1131  default_libgcc_cmp_return_mode)
1132
1133 /* Return machine mode for libgcc expanded shift instructions.  */
1134 DEFHOOK
1135 (libgcc_shift_count_mode,
1136  "",
1137  enum machine_mode, (void),
1138  default_libgcc_shift_count_mode)
1139
1140 /* Return machine mode to be used for _Unwind_Word type.  */
1141 DEFHOOK
1142 (unwind_word_mode,
1143  "",
1144  enum machine_mode, (void),
1145  default_unwind_word_mode)
1146
1147 /* Given two decls, merge their attributes and return the result.  */
1148 DEFHOOK
1149 (merge_decl_attributes,
1150  "",
1151  tree, (tree olddecl, tree newdecl),
1152  merge_decl_attributes)
1153
1154 /* Given two types, merge their attributes and return the result.  */
1155 DEFHOOK
1156 (merge_type_attributes,
1157  "",
1158  tree, (tree type1, tree type2),
1159  merge_type_attributes)
1160
1161 /* Table of machine attributes and functions to handle them.
1162    Ignored if NULL.  */
1163 DEFHOOKPOD
1164 (attribute_table,
1165  "",
1166  const struct attribute_spec *, NULL)
1167
1168 /* Return true iff attribute NAME expects a plain identifier as its first
1169    argument.  */
1170 DEFHOOK
1171 (attribute_takes_identifier_p,
1172  "",
1173  bool, (const_tree name),
1174  hook_bool_const_tree_false)
1175
1176 /* Return zero if the attributes on TYPE1 and TYPE2 are incompatible,
1177    one if they are compatible and two if they are nearly compatible
1178    (which causes a warning to be generated).  */
1179 DEFHOOK
1180 (comp_type_attributes,
1181  "",
1182  int, (const_tree type1, const_tree type2),
1183  hook_int_const_tree_const_tree_1)
1184
1185 /* Assign default attributes to the newly defined TYPE.  */
1186 DEFHOOK
1187 (set_default_type_attributes,
1188  "",
1189  void, (tree type),
1190  hook_void_tree)
1191
1192 /* Insert attributes on the newly created DECL.  */
1193 DEFHOOK
1194 (insert_attributes,
1195  "",
1196  void, (tree node, tree *attr_ptr),
1197  hook_void_tree_treeptr)
1198
1199 /* Return true if FNDECL (which has at least one machine attribute)
1200    can be inlined despite its machine attributes, false otherwise.  */
1201 DEFHOOK
1202 (function_attribute_inlinable_p,
1203  "",
1204  bool, (const_tree fndecl),
1205  hook_bool_const_tree_false)
1206
1207 /* Return true if bitfields in RECORD_TYPE should follow the
1208    Microsoft Visual C++ bitfield layout rules.  */
1209 DEFHOOK
1210 (ms_bitfield_layout_p,
1211  "",
1212  bool, (const_tree record_type),
1213  hook_bool_const_tree_false)
1214
1215 /* For now this is only an interface to WORDS_BIG_ENDIAN for
1216    target-independent code like the front ends, need performance testing
1217    before switching completely to the target hook.  */
1218 DEFHOOK_UNDOC
1219 (words_big_endian,
1220  "",
1221  bool, (void),
1222  targhook_words_big_endian)
1223
1224 /* Likewise for FLOAT_WORDS_BIG_ENDIAN.  */
1225 DEFHOOK_UNDOC
1226 (float_words_big_endian,
1227  "",
1228  bool, (void),
1229  targhook_float_words_big_endian)
1230
1231 /* True if the target supports decimal floating point.  */
1232 DEFHOOK
1233 (decimal_float_supported_p,
1234  "",
1235  bool, (void),
1236  default_decimal_float_supported_p)
1237
1238 /* True if the target supports fixed-point.  */
1239 DEFHOOK
1240 (fixed_point_supported_p,
1241  "",
1242  bool, (void),
1243  default_fixed_point_supported_p)
1244
1245 /* Return true if anonymous bitfields affect structure alignment.  */
1246 DEFHOOK
1247 (align_anon_bitfield,
1248  "",
1249  bool, (void),
1250  hook_bool_void_false)
1251
1252 /* Return true if volatile bitfields should use the narrowest type possible.
1253    Return false if they should use the container type.  */
1254 DEFHOOK
1255 (narrow_volatile_bitfield,
1256  "",
1257  bool, (void),
1258  hook_bool_void_false)
1259
1260 /* Set up target-specific built-in functions.  */
1261 DEFHOOK
1262 (init_builtins,
1263  "",
1264  void, (void),
1265  hook_void_void)
1266
1267 /* Initialize (if INITIALIZE_P is true) and return the target-specific
1268    built-in function decl for CODE.
1269    Return NULL if that is not possible.  Return error_mark_node if CODE
1270    is outside of the range of valid target builtin function codes.  */
1271 DEFHOOK
1272 (builtin_decl,
1273  "",
1274  tree, (unsigned code, bool initialize_p), NULL)
1275
1276 /* Expand a target-specific builtin.  */
1277 DEFHOOK
1278 (expand_builtin,
1279  "",
1280  rtx,
1281  (tree exp, rtx target, rtx subtarget, enum machine_mode mode, int ignore),
1282  default_expand_builtin)
1283
1284 /* Select a replacement for a target-specific builtin.  This is done
1285    *before* regular type checking, and so allows the target to
1286    implement a crude form of function overloading.  The result is a
1287    complete expression that implements the operation.  PARAMS really
1288    has type VEC(tree,gc)*, but we don't want to include tree.h here.  */
1289 DEFHOOK
1290 (resolve_overloaded_builtin,
1291  "",
1292  tree, (unsigned int /*location_t*/ loc, tree fndecl, void *arglist), NULL)
1293
1294 /* Fold a target-specific builtin.  */
1295 DEFHOOK
1296 (fold_builtin,
1297  "",
1298  tree, (tree fndecl, int n_args, tree *argp, bool ignore),
1299  hook_tree_tree_int_treep_bool_null)
1300
1301 /* Target hook is used to compare the target attributes in two functions to
1302    determine which function's features get higher priority.  This is used
1303    during function multi-versioning to figure out the order in which two
1304    versions must be dispatched.  A function version with a higher priority
1305    is checked for dispatching earlier.  DECL1 and DECL2 are
1306    the two function decls that will be compared. It returns positive value
1307    if DECL1 is higher priority,  negative value if DECL2 is higher priority
1308    and 0 if they are the same. */
1309 DEFHOOK
1310 (compare_version_priority,
1311  "",
1312  int, (tree decl1, tree decl2), NULL)
1313
1314 /*  Target hook is used to generate the dispatcher logic to invoke the right
1315     function version at run-time for a given set of function versions.
1316     ARG points to the callgraph node of the dispatcher function whose body
1317     must be generated.  */
1318 DEFHOOK
1319 (generate_version_dispatcher_body,
1320  "",
1321  tree, (void *arg), NULL)
1322
1323 /* Target hook is used to get the dispatcher function for a set of function
1324    versions.  The dispatcher function is called to invoke the right function
1325    version at run-time.  DECL is one version from a set of semantically
1326    identical versions.  */
1327 DEFHOOK
1328 (get_function_versions_dispatcher,
1329  "",
1330  tree, (void *decl), NULL)
1331
1332 /* Returns a code for a target-specific builtin that implements
1333    reciprocal of the function, or NULL_TREE if not available.  */
1334 DEFHOOK
1335 (builtin_reciprocal,
1336  "",
1337  tree, (unsigned fn, bool md_fn, bool sqrt),
1338  default_builtin_reciprocal)
1339
1340 /* For a vendor-specific TYPE, return a pointer to a statically-allocated
1341    string containing the C++ mangling for TYPE.  In all other cases, return
1342    NULL.  */
1343 DEFHOOK
1344 (mangle_type,
1345  "",
1346  const char *, (const_tree type),
1347  hook_constcharptr_const_tree_null)
1348
1349 /* Make any adjustments to libfunc names needed for this target.  */
1350 DEFHOOK
1351 (init_libfuncs,
1352  "",
1353  void, (void),
1354  hook_void_void)
1355
1356  /* Add a __gnu_ prefix to library functions rather than just __.  */
1357 DEFHOOKPOD
1358 (libfunc_gnu_prefix,
1359  "If false (the default), internal library routines start with two\n\
1360 underscores.  If set to true, these routines start with @code{__gnu_}\n\
1361 instead.  E.g., @code{__muldi3} changes to @code{__gnu_muldi3}.  This\n\
1362 currently only affects functions defined in @file{libgcc2.c}.  If this\n\
1363 is set to true, the @file{tm.h} file must also\n\
1364 @code{#define LIBGCC2_GNU_PREFIX}.",
1365   bool, false)
1366
1367 /* Given a decl, a section name, and whether the decl initializer
1368    has relocs, choose attributes for the section.  */
1369 /* ??? Should be merged with SELECT_SECTION and UNIQUE_SECTION.  */
1370 DEFHOOK
1371 (section_type_flags,
1372  "",
1373  unsigned int, (tree decl, const char *name, int reloc),
1374  default_section_type_flags)
1375
1376 /* True if new jumps cannot be created, to replace existing ones or
1377    not, at the current point in the compilation.  */
1378 DEFHOOK
1379 (cannot_modify_jumps_p,
1380  "",
1381  bool, (void),
1382  hook_bool_void_false)
1383
1384 /* True if FOLLOWER may be modified to follow FOLLOWEE.  */
1385 DEFHOOK
1386 (can_follow_jump,
1387  "FOLLOWER and FOLLOWEE are JUMP_INSN instructions;\
1388   return true if FOLLOWER may be modified to follow FOLLOWEE;\
1389   false, if it can't.\
1390   For example, on some targets, certain kinds of branches can't be made to\
1391   follow through a hot/cold partitioning.",
1392  bool, (const_rtx follower, const_rtx followee),
1393  hook_bool_const_rtx_const_rtx_true)
1394
1395 /* Return a register class for which branch target register
1396    optimizations should be applied.  */
1397 DEFHOOK
1398 (branch_target_register_class,
1399  "",
1400  reg_class_t, (void),
1401  default_branch_target_register_class)
1402
1403 /* Return true if branch target register optimizations should include
1404    callee-saved registers that are not already live during the current
1405    function.  AFTER_PE_GEN is true if prologues and epilogues have
1406    already been generated.  */
1407 DEFHOOK
1408 (branch_target_register_callee_saved,
1409  "",
1410  bool, (bool after_prologue_epilogue_gen),
1411  hook_bool_bool_false)
1412
1413 /* Return true if the target supports conditional execution.  */
1414 DEFHOOK
1415 (have_conditional_execution,
1416  "",
1417  bool, (void),
1418  default_have_conditional_execution)
1419
1420 /* Return a new value for loop unroll size.  */
1421 DEFHOOK
1422 (loop_unroll_adjust,
1423  "",
1424  unsigned, (unsigned nunroll, struct loop *loop),
1425  NULL)
1426
1427 /* True if X is a legitimate MODE-mode immediate operand.  */
1428 DEFHOOK
1429 (legitimate_constant_p,
1430  "",
1431  bool, (enum machine_mode mode, rtx x),
1432  hook_bool_mode_rtx_true)
1433
1434 /* True if the constant X cannot be placed in the constant pool.  */
1435 DEFHOOK
1436 (cannot_force_const_mem,
1437  "",
1438  bool, (enum machine_mode mode, rtx x),
1439  hook_bool_mode_rtx_false)
1440
1441 DEFHOOK_UNDOC
1442 (cannot_copy_insn_p,
1443  "True if the insn @var{x} cannot be duplicated.",
1444  bool, (rtx), NULL)
1445
1446 /* True if X is considered to be commutative.  */
1447 DEFHOOK
1448 (commutative_p,
1449  "",
1450  bool, (const_rtx x, int outer_code),
1451  hook_bool_const_rtx_commutative_p)
1452
1453 /* True if ADDR is an address-expression whose effect depends
1454    on the mode of the memory reference it is used in.  */
1455 DEFHOOK
1456 (mode_dependent_address_p,
1457  "",
1458  bool, (const_rtx addr, addr_space_t addrspace),
1459  default_mode_dependent_address_p)
1460
1461 /* Given an invalid address X for a given machine mode, try machine-specific
1462    ways to make it legitimate.  Return X or an invalid address on failure.  */
1463 DEFHOOK
1464 (legitimize_address,
1465  "",
1466  rtx, (rtx x, rtx oldx, enum machine_mode mode),
1467  default_legitimize_address)
1468
1469 /* Given an address RTX, undo the effects of LEGITIMIZE_ADDRESS.  */
1470 DEFHOOK
1471 (delegitimize_address,
1472  "",
1473  rtx, (rtx x),
1474  delegitimize_mem_from_attrs)
1475
1476 /* Given an RTX, return true if it is not ok to emit it into debug info
1477    section.  */
1478 DEFHOOK
1479 (const_not_ok_for_debug_p,
1480  "",
1481  bool, (rtx x),
1482  hook_bool_rtx_false)
1483
1484 /* Given an address RTX, say whether it is valid.  */
1485 DEFHOOK
1486 (legitimate_address_p,
1487  "",
1488  bool, (enum machine_mode mode, rtx x, bool strict),
1489  default_legitimate_address_p)
1490
1491 /* True if the given constant can be put into an object_block.  */
1492 DEFHOOK
1493 (use_blocks_for_constant_p,
1494  "",
1495  bool, (enum machine_mode mode, const_rtx x),
1496  hook_bool_mode_const_rtx_false)
1497
1498 /* True if the given decl can be put into an object_block.  */
1499 DEFHOOK
1500 (use_blocks_for_decl_p,
1501  "",
1502  bool, (const_tree decl),
1503  hook_bool_const_tree_true)
1504
1505 /* The minimum and maximum byte offsets for anchored addresses.  */
1506 DEFHOOKPOD
1507 (min_anchor_offset,
1508  "",
1509  HOST_WIDE_INT, 0)
1510
1511 DEFHOOKPOD
1512 (max_anchor_offset,
1513  "",
1514  HOST_WIDE_INT, 0)
1515
1516 /* True if section anchors can be used to access the given symbol.  */
1517 DEFHOOK
1518 (use_anchors_for_symbol_p,
1519  "",
1520  bool, (const_rtx x),
1521  default_use_anchors_for_symbol_p)
1522
1523 /* True if it is OK to do sibling call optimization for the specified
1524    call expression EXP.  DECL will be the called function, or NULL if
1525    this is an indirect call.  */
1526 DEFHOOK
1527 (function_ok_for_sibcall,
1528  "",
1529  bool, (tree decl, tree exp),
1530  hook_bool_tree_tree_false)
1531
1532 /* Establish appropriate back-end context for processing the function
1533    FNDECL.  The argument might be NULL to indicate processing at top
1534    level, outside of any function scope.  */
1535 DEFHOOK
1536 (set_current_function,
1537  "",
1538  void, (tree decl), hook_void_tree)
1539
1540 /* True if EXP should be placed in a "small data" section.  */
1541 DEFHOOK
1542 (in_small_data_p,
1543  "",
1544  bool, (const_tree exp),
1545  hook_bool_const_tree_false)
1546
1547 /* True if EXP names an object for which name resolution must resolve
1548    to the current executable or shared library.  */
1549 DEFHOOK
1550 (binds_local_p,
1551  "",
1552  bool, (const_tree exp),
1553  default_binds_local_p)
1554
1555 /* Check if profiling code is before or after prologue.  */
1556 DEFHOOK
1557 (profile_before_prologue,
1558  "It returns true if target wants profile code emitted before prologue.\n\n\
1559 The default version of this hook use the target macro\n\
1560 @code{PROFILE_BEFORE_PROLOGUE}.",
1561  bool, (void),
1562  default_profile_before_prologue)
1563
1564 /* Modify and return the identifier of a DECL's external name,
1565    originally identified by ID, as required by the target,
1566    (eg, append @nn to windows32 stdcall function names).
1567    The default is to return ID without modification. */
1568 DEFHOOK
1569 (mangle_decl_assembler_name,
1570  "",
1571  tree, (tree decl, tree  id),
1572  default_mangle_decl_assembler_name)
1573
1574 /* Do something target-specific to record properties of the DECL into
1575    the associated SYMBOL_REF.  */
1576 DEFHOOK
1577 (encode_section_info,
1578  "",
1579  void, (tree decl, rtx rtl, int new_decl_p),
1580  default_encode_section_info)
1581
1582 /* Undo the effects of encode_section_info on the symbol string.  */
1583 DEFHOOK
1584 (strip_name_encoding,
1585  "",
1586  const char *, (const char *name),
1587  default_strip_name_encoding)
1588
1589 /* If shift optabs for MODE are known to always truncate the shift count,
1590    return the mask that they apply.  Return 0 otherwise.  */
1591 DEFHOOK
1592 (shift_truncation_mask,
1593  "",
1594  unsigned HOST_WIDE_INT, (enum machine_mode mode),
1595  default_shift_truncation_mask)
1596
1597 /* Return the number of divisions in the given MODE that should be present,
1598    so that it is profitable to turn the division into a multiplication by
1599    the reciprocal.  */
1600 DEFHOOK
1601 (min_divisions_for_recip_mul,
1602  "",
1603  unsigned int, (enum machine_mode mode),
1604  default_min_divisions_for_recip_mul)
1605
1606 /* If the representation of integral MODE is such that values are
1607    always sign-extended to a wider mode MODE_REP then return
1608    SIGN_EXTEND.  Return UNKNOWN otherwise.  */
1609 /* Note that the return type ought to be RTX_CODE, but that's not
1610    necessarily defined at this point.  */
1611 DEFHOOK
1612 (mode_rep_extended,
1613  "",
1614  int, (enum machine_mode mode, enum machine_mode rep_mode),
1615  default_mode_rep_extended)
1616
1617 /* True if MODE is valid for a pointer in __attribute__((mode("MODE"))).  */
1618 DEFHOOK
1619 (valid_pointer_mode,
1620  "",
1621  bool, (enum machine_mode mode),
1622  default_valid_pointer_mode)
1623
1624 /* Disambiguate with errno.  */
1625 DEFHOOK
1626 (ref_may_alias_errno,
1627  "Define this to return nonzero if the memory reference @var{ref}\
1628   may alias with the system C library errno location.  The default\
1629   version of this hook assumes the system C library errno location\
1630   is either a declaration of type int or accessed by dereferencing\
1631   a pointer to int.",
1632  bool, (struct ao_ref_s *ref),
1633  default_ref_may_alias_errno)
1634
1635 /* Support for named address spaces.  */
1636 #undef HOOK_PREFIX
1637 #define HOOK_PREFIX "TARGET_ADDR_SPACE_"
1638 HOOK_VECTOR (TARGET_ADDR_SPACE_HOOKS, addr_space)
1639
1640 /* MODE to use for a pointer into another address space.  */
1641 DEFHOOK
1642 (pointer_mode,
1643  "",
1644  enum machine_mode, (addr_space_t address_space),
1645  default_addr_space_pointer_mode)
1646
1647 /* MODE to use for an address in another address space.  */
1648 DEFHOOK
1649 (address_mode,
1650  "",
1651  enum machine_mode, (addr_space_t address_space),
1652  default_addr_space_address_mode)
1653
1654 /* True if MODE is valid for a pointer in __attribute__((mode("MODE")))
1655    in another address space.  */
1656 DEFHOOK
1657 (valid_pointer_mode,
1658  "",
1659  bool, (enum machine_mode mode, addr_space_t as),
1660  default_addr_space_valid_pointer_mode)
1661
1662 /* True if an address is a valid memory address to a given named address
1663    space for a given mode.  */
1664 DEFHOOK
1665 (legitimate_address_p,
1666  "",
1667  bool, (enum machine_mode mode, rtx exp, bool strict, addr_space_t as),
1668  default_addr_space_legitimate_address_p)
1669
1670 /* Return an updated address to convert an invalid pointer to a named
1671    address space to a valid one.  If NULL_RTX is returned use machine
1672    independent methods to make the address valid.  */
1673 DEFHOOK
1674 (legitimize_address,
1675  "",
1676  rtx, (rtx x, rtx oldx, enum machine_mode mode, addr_space_t as),
1677  default_addr_space_legitimize_address)
1678
1679 /* True if one named address space is a subset of another named address. */
1680 DEFHOOK
1681 (subset_p,
1682  "",
1683  bool, (addr_space_t subset, addr_space_t superset),
1684  default_addr_space_subset_p)
1685
1686 /* Function to convert an rtl expression from one address space to another.  */
1687 DEFHOOK
1688 (convert,
1689  "",
1690  rtx, (rtx op, tree from_type, tree to_type),
1691  default_addr_space_convert)
1692
1693 HOOK_VECTOR_END (addr_space)
1694
1695 #undef HOOK_PREFIX
1696 #define HOOK_PREFIX "TARGET_"
1697
1698 /* True if MODE is valid for the target.  By "valid", we mean able to
1699    be manipulated in non-trivial ways.  In particular, this means all
1700    the arithmetic is supported.  */
1701 DEFHOOK
1702 (scalar_mode_supported_p,
1703  "",
1704  bool, (enum machine_mode mode),
1705  default_scalar_mode_supported_p)
1706
1707 /* Similarly for vector modes.  "Supported" here is less strict.  At
1708    least some operations are supported; need to check optabs or builtins
1709    for further details.  */
1710 DEFHOOK
1711 (vector_mode_supported_p,
1712  "",
1713  bool, (enum machine_mode mode),
1714  hook_bool_mode_false)
1715
1716 DEFHOOK
1717 (vector_alignment,
1718  "This hook can be used to define the alignment for a vector of type\n\
1719 @var{type}, in order to comply with a platform ABI.  The default is to\n\
1720 require natural alignment for vector types.  The alignment returned by\n\
1721 this hook must be a power-of-two multiple of the default alignment of\n\
1722 the vector element type.",
1723  HOST_WIDE_INT, (const_tree type),
1724  default_vector_alignment)
1725
1726 /* True if we should try to use a scalar mode to represent an array,
1727    overriding the usual MAX_FIXED_MODE limit.  */
1728 DEFHOOK
1729 (array_mode_supported_p,
1730  "Return true if GCC should try to use a scalar mode to store an array\n\
1731 of @var{nelems} elements, given that each element has mode @var{mode}.\n\
1732 Returning true here overrides the usual @code{MAX_FIXED_MODE} limit\n\
1733 and allows GCC to use any defined integer mode.\n\
1734 \n\
1735 One use of this hook is to support vector load and store operations\n\
1736 that operate on several homogeneous vectors.  For example, ARM NEON\n\
1737 has operations like:\n\
1738 \n\
1739 @smallexample\n\
1740 int8x8x3_t vld3_s8 (const int8_t *)\n\
1741 @end smallexample\n\
1742 \n\
1743 where the return type is defined as:\n\
1744 \n\
1745 @smallexample\n\
1746 typedef struct int8x8x3_t\n\
1747 @{\n\
1748   int8x8_t val[3];\n\
1749 @} int8x8x3_t;\n\
1750 @end smallexample\n\
1751 \n\
1752 If this hook allows @code{val} to have a scalar mode, then\n\
1753 @code{int8x8x3_t} can have the same mode.  GCC can then store\n\
1754 @code{int8x8x3_t}s in registers rather than forcing them onto the stack.",
1755  bool, (enum machine_mode mode, unsigned HOST_WIDE_INT nelems),
1756  hook_bool_mode_uhwi_false)
1757
1758 /* Compute cost of moving data from a register of class FROM to one of
1759    TO, using MODE.  */
1760 DEFHOOK
1761 (register_move_cost,
1762  "",
1763  int, (enum machine_mode mode, reg_class_t from, reg_class_t to),
1764  default_register_move_cost)
1765
1766 /* Compute cost of moving registers to/from memory.  */
1767 /* ??? Documenting the argument types for this hook requires a GFDL
1768    license grant.  Also, the documentation uses a different name for RCLASS.  */
1769 DEFHOOK
1770 (memory_move_cost,
1771  "",
1772  int, (enum machine_mode mode, reg_class_t rclass, bool in),
1773  default_memory_move_cost)
1774
1775 /* True for MODE if the target expects that registers in this mode will
1776    be allocated to registers in a small register class.  The compiler is
1777    allowed to use registers explicitly used in the rtl as spill registers
1778    but it should prevent extending the lifetime of these registers.  */
1779 DEFHOOK
1780 (small_register_classes_for_mode_p,
1781  "",
1782  bool, (enum machine_mode mode),
1783  hook_bool_mode_false)
1784
1785 /* Register number for a flags register.  Only needs to be defined if the
1786    target is constrainted to use post-reload comparison elimination.  */
1787 DEFHOOKPOD
1788 (flags_regnum,
1789  "If the target has a dedicated flags register, and it needs to use the\
1790  post-reload comparison elimination pass, then this value should be set\
1791  appropriately.",
1792  unsigned int, INVALID_REGNUM)
1793
1794 /* Compute a (partial) cost for rtx X.  Return true if the complete
1795    cost has been computed, and false if subexpressions should be
1796    scanned.  In either case, *TOTAL contains the cost result.  */
1797 /* Note that CODE and OUTER_CODE ought to be RTX_CODE, but that's
1798    not necessarily defined at this point.  */
1799 DEFHOOK
1800 (rtx_costs,
1801  "",
1802  bool, (rtx x, int code, int outer_code, int opno, int *total, bool speed),
1803  hook_bool_rtx_int_int_int_intp_bool_false)
1804
1805 /* Compute the cost of X, used as an address.  Never called with
1806    invalid addresses.  */
1807 DEFHOOK
1808 (address_cost,
1809  "",
1810  int, (rtx address, enum machine_mode mode, addr_space_t as, bool speed),
1811  default_address_cost)
1812
1813 /* Return where to allocate pseudo for a given hard register initial value.  */
1814 DEFHOOK
1815 (allocate_initial_value,
1816  "",
1817  rtx, (rtx hard_reg), NULL)
1818
1819 /* Return nonzero if evaluating UNSPEC X might cause a trap.
1820    FLAGS has the same meaning as in rtlanal.c: may_trap_p_1.  */
1821 DEFHOOK
1822 (unspec_may_trap_p,
1823  "",
1824  int, (const_rtx x, unsigned flags),
1825  default_unspec_may_trap_p)
1826
1827 /* Given a register, this hook should return a parallel of registers
1828    to represent where to find the register pieces.  Define this hook
1829    if the register and its mode are represented in Dwarf in
1830    non-contiguous locations, or if the register should be
1831    represented in more than one register in Dwarf.  Otherwise, this
1832    hook should return NULL_RTX.  */
1833 DEFHOOK
1834 (dwarf_register_span,
1835  "",
1836  rtx, (rtx reg),
1837  hook_rtx_rtx_null)
1838
1839 /* If expand_builtin_init_dwarf_reg_sizes needs to fill in table
1840    entries not corresponding directly to registers below
1841    FIRST_PSEUDO_REGISTER, this hook should generate the necessary
1842    code, given the address of the table.  */
1843 DEFHOOK
1844 (init_dwarf_reg_sizes_extra,
1845  "",
1846  void, (tree address),
1847  hook_void_tree)
1848
1849 /* Fetch the fixed register(s) which hold condition codes, for
1850    targets where it makes sense to look for duplicate assignments to
1851    the condition codes.  This should return true if there is such a
1852    register, false otherwise.  The arguments should be set to the
1853    fixed register numbers.  Up to two condition code registers are
1854    supported.  If there is only one for this target, the int pointed
1855    at by the second argument should be set to -1.  */
1856 DEFHOOK
1857 (fixed_condition_code_regs,
1858  "",
1859  bool, (unsigned int *p1, unsigned int *p2),
1860  hook_bool_uintp_uintp_false)
1861
1862 /* If two condition code modes are compatible, return a condition
1863      code mode which is compatible with both, such that a comparison
1864      done in the returned mode will work for both of the original
1865      modes.  If the condition code modes are not compatible, return
1866      VOIDmode.  */
1867 DEFHOOK
1868 (cc_modes_compatible,
1869  "",
1870  enum machine_mode, (enum machine_mode m1, enum machine_mode m2),
1871  default_cc_modes_compatible)
1872
1873 /* Do machine-dependent code transformations.  Called just before
1874      delayed-branch scheduling.  */
1875 DEFHOOK
1876 (machine_dependent_reorg,
1877  "",
1878  void, (void), NULL)
1879
1880 /* Create the __builtin_va_list type.  */
1881 DEFHOOK
1882 (build_builtin_va_list,
1883  "",
1884  tree, (void),
1885  std_build_builtin_va_list)
1886
1887 /* Enumerate the va list variants.  */
1888 DEFHOOK
1889 (enum_va_list_p,
1890  "",
1891  int, (int idx, const char **pname, tree *ptree),
1892  NULL)
1893
1894 /* Get the cfun/fndecl calling abi __builtin_va_list type.  */
1895 DEFHOOK
1896 (fn_abi_va_list,
1897  "",
1898  tree, (tree fndecl),
1899  std_fn_abi_va_list)
1900
1901 /* Get the __builtin_va_list type dependent on input type.  */
1902 DEFHOOK
1903 (canonical_va_list_type,
1904  "",
1905  tree, (tree type),
1906  std_canonical_va_list_type)
1907
1908 /* ??? Documenting this hook requires a GFDL license grant.  */
1909 DEFHOOK_UNDOC
1910 (expand_builtin_va_start,
1911 "Expand the @code{__builtin_va_start} builtin.",
1912  void, (tree valist, rtx nextarg), NULL)
1913
1914 /* Gimplifies a VA_ARG_EXPR.  */
1915 DEFHOOK
1916 (gimplify_va_arg_expr,
1917  "",
1918  tree, (tree valist, tree type, gimple_seq *pre_p, gimple_seq *post_p),
1919  std_gimplify_va_arg_expr)
1920
1921 /* Validity-checking routines for PCH files, target-specific.
1922    get_pch_validity returns a pointer to the data to be stored,
1923    and stores the size in its argument.  pch_valid_p gets the same
1924    information back and returns NULL if the PCH is valid,
1925    or an error message if not.  */
1926 DEFHOOK
1927 (get_pch_validity,
1928  "",
1929  void *, (size_t *sz),
1930  default_get_pch_validity)
1931
1932 DEFHOOK
1933 (pch_valid_p,
1934  "",
1935  const char *, (const void *data, size_t sz),
1936  default_pch_valid_p)
1937
1938 DEFHOOK
1939 (prepare_pch_save,
1940  "Called before writing out a PCH file.  If the target has some\n\
1941 garbage-collected data that needs to be in a particular state on PCH loads,\n\
1942 it can use this hook to enforce that state.  Very few targets need\n\
1943 to do anything here.",
1944  void, (void),
1945  hook_void_void)
1946
1947 /* If nonnull, this function checks whether a PCH file with the
1948    given set of target flags can be used.  It returns NULL if so,
1949    otherwise it returns an error message.  */
1950 DEFHOOK
1951 (check_pch_target_flags,
1952  "",
1953  const char *, (int pch_flags), NULL)
1954
1955 /* True if the compiler should give an enum type only as many
1956    bytes as it takes to represent the range of possible values of
1957    that type.  */
1958 DEFHOOK
1959 (default_short_enums,
1960  "",
1961  bool, (void),
1962  hook_bool_void_false)
1963
1964 /* This target hook returns an rtx that is used to store the address
1965    of the current frame into the built-in setjmp buffer.  */
1966 DEFHOOK
1967 (builtin_setjmp_frame_value,
1968  "",
1969  rtx, (void),
1970  default_builtin_setjmp_frame_value)
1971
1972 /* This target hook should add STRING_CST trees for any hard regs
1973    the port wishes to automatically clobber for an asm.  */
1974 DEFHOOK
1975 (md_asm_clobbers,
1976  "",
1977  tree, (tree outputs, tree inputs, tree clobbers),
1978  hook_tree_tree_tree_tree_3rd_identity)
1979
1980 /* This target hook allows the backend to specify a calling convention
1981    in the debug information.  This function actually returns an
1982    enum dwarf_calling_convention, but because of forward declarations
1983    and not wanting to include dwarf2.h everywhere target.h is included
1984    the function is being declared as an int.  */
1985 DEFHOOK
1986 (dwarf_calling_convention,
1987  "",
1988  int, (const_tree function),
1989  hook_int_const_tree_0)
1990
1991 /* This target hook allows the backend to emit frame-related insns that
1992    contain UNSPECs or UNSPEC_VOLATILEs.  The call frame debugging info
1993    engine will invoke it on insns of the form
1994      (set (reg) (unspec [...] UNSPEC_INDEX))
1995    and
1996      (set (reg) (unspec_volatile [...] UNSPECV_INDEX))
1997    to let the backend emit the call frame instructions.  */
1998 DEFHOOK
1999 (dwarf_handle_frame_unspec,
2000  "",
2001  void, (const char *label, rtx pattern, int index), NULL)
2002
2003 /* ??? Documenting this hook requires a GFDL license grant.  */
2004 DEFHOOK_UNDOC
2005 (stdarg_optimize_hook,
2006 "Perform architecture specific checking of statements gimplified\
2007  from @code{VA_ARG_EXPR}.  @var{stmt} is the statement.  Returns true if\
2008  the statement doesn't need to be checked for @code{va_list} references.",
2009  bool, (struct stdarg_info *ai, const_gimple stmt), NULL)
2010
2011 /* This target hook allows the operating system to override the DECL
2012    that represents the external variable that contains the stack
2013    protection guard variable.  The type of this DECL is ptr_type_node.  */
2014 DEFHOOK
2015 (stack_protect_guard,
2016  "",
2017  tree, (void),
2018  default_stack_protect_guard)
2019
2020 /* This target hook allows the operating system to override the CALL_EXPR
2021    that is invoked when a check vs the guard variable fails.  */
2022 DEFHOOK
2023 (stack_protect_fail,
2024  "",
2025  tree, (void),
2026  default_external_stack_protect_fail)
2027
2028 /* Returns NULL if target supports the insn within a doloop block,
2029    otherwise it returns an error message.  */
2030 DEFHOOK
2031 (invalid_within_doloop,
2032  "",
2033  const char *, (const_rtx insn),
2034  default_invalid_within_doloop)
2035
2036 /* Returns true for a legitimate combined insn.  */
2037 DEFHOOK
2038 (legitimate_combined_insn,
2039 "Take an instruction in @var{insn} and return @code{false} if the instruction\
2040  is not appropriate as a combination of two or more instructions.  The\
2041  default is to accept all instructions.",
2042  bool, (rtx insn),
2043  hook_bool_rtx_true)
2044
2045 DEFHOOK
2046 (valid_dllimport_attribute_p,
2047 "@var{decl} is a variable or function with @code{__attribute__((dllimport))}\
2048  specified.  Use this hook if the target needs to add extra validation\
2049  checks to @code{handle_dll_attribute}.",
2050  bool, (const_tree decl),
2051  hook_bool_const_tree_true)
2052
2053 /* If non-zero, align constant anchors in CSE to a multiple of this
2054    value.  */
2055 DEFHOOKPOD
2056 (const_anchor,
2057  "",
2058  unsigned HOST_WIDE_INT, 0)
2059
2060 /* Defines, which target-dependent bits (upper 16) are used by port  */
2061 DEFHOOK
2062 (memmodel_check,
2063  "",
2064  unsigned HOST_WIDE_INT, (unsigned HOST_WIDE_INT val), NULL)
2065
2066 /* Defines an offset bitwise ored into shifted address to get corresponding
2067    Address Sanitizer shadow address, or -1 if Address Sanitizer is not
2068    supported by the target.  */
2069 DEFHOOK
2070 (asan_shadow_offset,
2071  "Return the offset bitwise ored into shifted address to get corresponding\n\
2072 Address Sanitizer shadow memory address.  NULL if Address Sanitizer is not\n\
2073 supported by the target.",
2074  unsigned HOST_WIDE_INT, (void),
2075  NULL)
2076
2077 /* Functions relating to calls - argument passing, returns, etc.  */
2078 /* Members of struct call have no special macro prefix.  */
2079 HOOK_VECTOR (TARGET_CALLS, calls)
2080
2081 DEFHOOK
2082 (promote_function_mode,
2083  "",
2084  enum machine_mode, (const_tree type, enum machine_mode mode, int *punsignedp,
2085                      const_tree funtype, int for_return),
2086  default_promote_function_mode)
2087
2088 DEFHOOK
2089 (promote_prototypes,
2090  "",
2091  bool, (const_tree fntype),
2092  hook_bool_const_tree_false)
2093
2094 DEFHOOK
2095 (struct_value_rtx,
2096  "",
2097  rtx, (tree fndecl, int incoming),
2098  hook_rtx_tree_int_null)
2099 DEFHOOK
2100 (return_in_memory,
2101  "",
2102  bool, (const_tree type, const_tree fntype),
2103  default_return_in_memory)
2104
2105 DEFHOOK
2106 (return_in_msb,
2107  "",
2108  bool, (const_tree type),
2109  hook_bool_const_tree_false)
2110
2111 /* Return true if a parameter must be passed by reference.  TYPE may
2112    be null if this is a libcall.  CA may be null if this query is
2113    from __builtin_va_arg.  */
2114 DEFHOOK
2115 (pass_by_reference,
2116  "",
2117  bool,
2118  (cumulative_args_t cum, enum machine_mode mode, const_tree type, bool named),
2119  hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false)
2120
2121 DEFHOOK
2122 (expand_builtin_saveregs,
2123  "",
2124  rtx, (void),
2125  default_expand_builtin_saveregs)
2126
2127 /* Returns pretend_argument_size.  */
2128 DEFHOOK
2129 (setup_incoming_varargs,
2130  "",
2131  void, (cumulative_args_t args_so_far, enum machine_mode mode, tree type,
2132         int *pretend_args_size, int second_time),
2133  default_setup_incoming_varargs)
2134
2135 DEFHOOK
2136 (strict_argument_naming,
2137  "",
2138  bool, (cumulative_args_t ca),
2139  hook_bool_CUMULATIVE_ARGS_false)
2140
2141 /* Returns true if we should use
2142    targetm.calls.setup_incoming_varargs() and/or
2143    targetm.calls.strict_argument_naming().  */
2144 DEFHOOK
2145 (pretend_outgoing_varargs_named,
2146  "",
2147  bool, (cumulative_args_t ca),
2148  default_pretend_outgoing_varargs_named)
2149
2150 /* Given a complex type T, return true if a parameter of type T
2151    should be passed as two scalars.  */
2152 DEFHOOK
2153 (split_complex_arg,
2154  "",
2155  bool, (const_tree type), NULL)
2156
2157 /* Return true if type T, mode MODE, may not be passed in registers,
2158    but must be passed on the stack.  */
2159 /* ??? This predicate should be applied strictly after pass-by-reference.
2160    Need audit to verify that this is the case.  */
2161 DEFHOOK
2162 (must_pass_in_stack,
2163  "",
2164  bool, (enum machine_mode mode, const_tree type),
2165  must_pass_in_stack_var_size_or_pad)
2166
2167 /* Return true if type TYPE, mode MODE, which is passed by reference,
2168    should have the object copy generated by the callee rather than
2169    the caller.  It is never called for TYPE requiring constructors.  */
2170 DEFHOOK
2171 (callee_copies,
2172  "",
2173  bool,
2174  (cumulative_args_t cum, enum machine_mode mode, const_tree type, bool named),
2175  hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false)
2176
2177 /* Return zero for arguments passed entirely on the stack or entirely
2178    in registers.  If passed in both, return the number of bytes passed
2179    in registers; the balance is therefore passed on the stack.  */
2180 DEFHOOK
2181 (arg_partial_bytes,
2182  "",
2183  int, (cumulative_args_t cum, enum machine_mode mode, tree type, bool named),
2184  hook_int_CUMULATIVE_ARGS_mode_tree_bool_0)
2185
2186 /* Update the state in CA to advance past an argument in the
2187    argument list.  The values MODE, TYPE, and NAMED describe that
2188    argument.  */
2189 DEFHOOK
2190 (function_arg_advance,
2191  "",
2192  void,
2193  (cumulative_args_t ca, enum machine_mode mode, const_tree type, bool named),
2194  default_function_arg_advance)
2195
2196 /* Return zero if the argument described by the state of CA should
2197    be placed on a stack, or a hard register in which to store the
2198    argument.  The values MODE, TYPE, and NAMED describe that
2199    argument.  */
2200 DEFHOOK
2201 (function_arg,
2202  "",
2203  rtx, (cumulative_args_t ca, enum machine_mode mode, const_tree type,
2204        bool named),
2205  default_function_arg)
2206
2207 /* Likewise, but for machines with register windows.  Return the
2208    location where the argument will appear to the callee.  */
2209 DEFHOOK
2210 (function_incoming_arg,
2211  "",
2212  rtx, (cumulative_args_t ca, enum machine_mode mode, const_tree type,
2213        bool named),
2214  default_function_incoming_arg)
2215
2216 DEFHOOK
2217 (function_arg_boundary,
2218  "",
2219  unsigned int, (enum machine_mode mode, const_tree type),
2220  default_function_arg_boundary)
2221
2222 DEFHOOK
2223 (function_arg_round_boundary,
2224  "Normally, the size of an argument is rounded up to @code{PARM_BOUNDARY},\n\
2225 which is the default value for this hook.  You can define this hook to\n\
2226 return a different value if an argument size must be rounded to a larger\n\
2227 value.",
2228  unsigned int, (enum machine_mode mode, const_tree type),
2229  default_function_arg_round_boundary)
2230
2231 /* Return the diagnostic message string if function without a prototype
2232    is not allowed for this 'val' argument; NULL otherwise. */
2233 DEFHOOK
2234 (invalid_arg_for_unprototyped_fn,
2235  "",
2236  const char *, (const_tree typelist, const_tree funcdecl, const_tree val),
2237  hook_invalid_arg_for_unprototyped_fn)
2238
2239 /* Return an rtx for the return value location of the function
2240    specified by FN_DECL_OR_TYPE with a return type of RET_TYPE.  */
2241 DEFHOOK
2242 (function_value,
2243  "",
2244  rtx, (const_tree ret_type, const_tree fn_decl_or_type, bool outgoing),
2245  default_function_value)
2246
2247 /* Return the rtx for the result of a libcall of mode MODE,
2248    calling the function FN_NAME.  */
2249 DEFHOOK
2250 (libcall_value,
2251  "",
2252  rtx, (enum machine_mode mode, const_rtx fun),
2253  default_libcall_value)
2254
2255 /* Return true if REGNO is a possible register number for
2256    a function value as seen by the caller.  */
2257 DEFHOOK
2258 (function_value_regno_p,
2259  "",
2260  bool, (const unsigned int regno),
2261  default_function_value_regno_p)
2262
2263 /* ??? Documenting this hook requires a GFDL license grant.  */
2264 DEFHOOK_UNDOC
2265 (internal_arg_pointer,
2266 "Return an rtx for the argument pointer incoming to the\
2267  current function.",
2268  rtx, (void),
2269  default_internal_arg_pointer)
2270
2271 /* Update the current function stack boundary if needed.  */
2272 DEFHOOK
2273 (update_stack_boundary,
2274  "",
2275  void, (void), NULL)
2276
2277 /* Handle stack alignment and return an rtx for Dynamic Realign
2278    Argument Pointer if necessary.  */
2279 DEFHOOK
2280 (get_drap_rtx,
2281  "",
2282  rtx, (void), NULL)
2283
2284 /* Return true if all function parameters should be spilled to the
2285    stack.  */
2286 DEFHOOK
2287 (allocate_stack_slots_for_args,
2288  "",
2289  bool, (void),
2290  hook_bool_void_true)
2291
2292 /* Return an rtx for the static chain for FNDECL.  If INCOMING_P is true,
2293        then it should be for the callee; otherwise for the caller.  */
2294 DEFHOOK
2295 (static_chain,
2296  "",
2297  rtx, (const_tree fndecl, bool incoming_p),
2298  default_static_chain)
2299
2300 /* Fill in the trampoline at MEM with a call to FNDECL and a
2301    static chain value of CHAIN.  */
2302 DEFHOOK
2303 (trampoline_init,
2304  "",
2305  void, (rtx m_tramp, tree fndecl, rtx static_chain),
2306  default_trampoline_init)
2307
2308 /* Adjust the address of the trampoline in a target-specific way.  */
2309 DEFHOOK
2310 (trampoline_adjust_address,
2311  "",
2312  rtx, (rtx addr), NULL)
2313
2314 /* Return the number of bytes of its own arguments that a function
2315    pops on returning, or 0 if the function pops no arguments and the
2316    caller must therefore pop them all after the function returns.  */
2317 /* ??? tm.texi has no types for the parameters.  */
2318 DEFHOOK
2319 (return_pops_args,
2320  "",
2321  int, (tree fundecl, tree funtype, int size),
2322  default_return_pops_args)
2323
2324 /* Return a mode wide enough to copy any function value that might be
2325    returned.  */
2326 DEFHOOK
2327 (get_raw_result_mode,
2328  "This target hook returns the mode to be used when accessing raw return\
2329  registers in @code{__builtin_return}.  Define this macro if the value\
2330  in @var{reg_raw_mode} is not correct.",
2331  enum machine_mode, (int regno),
2332  default_get_reg_raw_mode)
2333
2334 /* Return a mode wide enough to copy any argument value that might be
2335    passed.  */
2336 DEFHOOK
2337 (get_raw_arg_mode,
2338  "This target hook returns the mode to be used when accessing raw argument\
2339  registers in @code{__builtin_apply_args}.  Define this macro if the value\
2340  in @var{reg_raw_mode} is not correct.",
2341  enum machine_mode, (int regno),
2342  default_get_reg_raw_mode)
2343
2344 HOOK_VECTOR_END (calls)
2345
2346 /* Return the diagnostic message string if conversion from FROMTYPE
2347    to TOTYPE is not allowed, NULL otherwise.  */
2348 DEFHOOK
2349 (invalid_conversion,
2350  "",
2351  const char *, (const_tree fromtype, const_tree totype),
2352  hook_constcharptr_const_tree_const_tree_null)
2353
2354 /* Return the diagnostic message string if the unary operation OP is
2355    not permitted on TYPE, NULL otherwise.  */
2356 DEFHOOK
2357 (invalid_unary_op,
2358  "",
2359  const char *, (int op, const_tree type),
2360  hook_constcharptr_int_const_tree_null)
2361
2362 /* Return the diagnostic message string if the binary operation OP
2363    is not permitted on TYPE1 and TYPE2, NULL otherwise.  */
2364 DEFHOOK
2365 (invalid_binary_op,
2366  "",
2367  const char *, (int op, const_tree type1, const_tree type2),
2368  hook_constcharptr_int_const_tree_const_tree_null)
2369
2370 /* Return the diagnostic message string if TYPE is not valid as a
2371    function parameter type, NULL otherwise.  */
2372 DEFHOOK
2373 (invalid_parameter_type,
2374  "",
2375  const char *, (const_tree type),
2376  hook_constcharptr_const_tree_null)
2377
2378 /* Return the diagnostic message string if TYPE is not valid as a
2379    function return type, NULL otherwise.  */
2380 DEFHOOK
2381 (invalid_return_type,
2382  "",
2383  const char *, (const_tree type),
2384  hook_constcharptr_const_tree_null)
2385
2386 /* If values of TYPE are promoted to some other type when used in
2387    expressions (analogous to the integer promotions), return that type,
2388    or NULL_TREE otherwise.  */
2389 DEFHOOK
2390 (promoted_type,
2391  "",
2392  tree, (const_tree type),
2393  hook_tree_const_tree_null)
2394
2395 /* Convert EXPR to TYPE, if target-specific types with special conversion
2396    rules are involved.  Return the converted expression, or NULL to apply
2397    the standard conversion rules.  */
2398 DEFHOOK
2399 (convert_to_type,
2400  "",
2401  tree, (tree type, tree expr),
2402  hook_tree_tree_tree_null)
2403
2404 /* Return true if we use LRA instead of reload.  */
2405 DEFHOOK
2406 (lra_p,
2407  "A target hook which returns true if we use LRA instead of reload pass.\
2408   It means that LRA was ported to the target.\
2409   \
2410   The default version of this target hook returns always false.",
2411  bool, (void),
2412  default_lra_p)
2413
2414 /* Return register priority of given hard regno for the current target.  */
2415 DEFHOOK
2416 (register_priority,
2417  "A target hook which returns the register priority number to which the\
2418   register @var{hard_regno} belongs to.  The bigger the number, the\
2419   more preferable the hard register usage (when all other conditions are\
2420   the same).  This hook can be used to prefer some hard register over\
2421   others in LRA.  For example, some x86-64 register usage needs\
2422   additional prefix which makes instructions longer.  The hook can\
2423   return lower priority number for such registers make them less favorable\
2424   and as result making the generated code smaller.\
2425   \
2426   The default version of this target hook returns always zero.",
2427  int, (int),
2428  default_register_priority)
2429
2430 /* Return true if maximal address displacement can be different.  */
2431 DEFHOOK
2432 (different_addr_displacement_p,
2433  "A target hook which returns true if an address with the same structure\
2434   can have different maximal legitimate displacement.  For example, the\
2435   displacement can depend on memory mode or on operand combinations in\
2436   the insn.\
2437   \
2438   The default version of this target hook returns always false.",
2439  bool, (void),
2440  default_different_addr_displacement_p)
2441
2442 /* Determine class for spilling pseudos of given mode into registers
2443    instead of memory.  */
2444 DEFHOOK
2445 (spill_class,
2446  "This hook defines a class of registers which could be used for spilling\
2447   pseudos of the given mode and class, or @code{NO_REGS} if only memory\
2448   should be used.  Not defining this hook is equivalent to returning\
2449   @code{NO_REGS} for all inputs.",
2450  reg_class_t, (reg_class_t, enum machine_mode),
2451  NULL)
2452
2453 /* True if a structure, union or array with MODE containing FIELD should
2454    be accessed using BLKmode.  */
2455 DEFHOOK
2456 (member_type_forces_blk,
2457  "",
2458  bool, (const_tree field, enum machine_mode mode),
2459  default_member_type_forces_blk)
2460
2461 /* Return the class for a secondary reload, and fill in extra information.  */
2462 DEFHOOK
2463 (secondary_reload,
2464  "",
2465  reg_class_t,
2466  (bool in_p, rtx x, reg_class_t reload_class, enum machine_mode reload_mode,
2467   secondary_reload_info *sri),
2468  default_secondary_reload)
2469
2470 /* Given an rtx X being reloaded into a reg required to be in class CLASS,
2471    return the class of reg to actually use.  */
2472 DEFHOOK
2473 (preferred_reload_class,
2474  "",
2475  reg_class_t,
2476  (rtx x, reg_class_t rclass),
2477  default_preferred_reload_class)
2478
2479 /* Like TARGET_PREFERRED_RELOAD_CLASS, but for output reloads instead of
2480    input reloads.  */
2481 DEFHOOK
2482 (preferred_output_reload_class,
2483  "",
2484  reg_class_t,
2485  (rtx x, reg_class_t rclass),
2486  default_preferred_output_reload_class)
2487
2488 DEFHOOK
2489 (class_likely_spilled_p,
2490  "",
2491  bool, (reg_class_t rclass),
2492  default_class_likely_spilled_p)
2493
2494 /* Return the maximum number of consecutive registers
2495    needed to represent mode MODE in a register of class RCLASS.  */
2496 DEFHOOK
2497 (class_max_nregs,
2498  "",
2499  unsigned char, (reg_class_t rclass, enum machine_mode mode),
2500  default_class_max_nregs)
2501
2502 DEFHOOK
2503 (preferred_rename_class,
2504  "A target hook that places additional preference on the register\
2505  class to use when it is necessary to rename a register in class\
2506  @var{rclass} to another class, or perhaps @var{NO_REGS}, if no\
2507  preferred register class is found or hook @code{preferred_rename_class}\
2508  is not implemented.\
2509  Sometimes returning a more restrictive class makes better code.  For\
2510  example, on ARM, thumb-2 instructions using @code{LO_REGS} may be\
2511  smaller than instructions using @code{GENERIC_REGS}.  By returning\
2512  @code{LO_REGS} from @code{preferred_rename_class}, code size can\
2513  be reduced.",
2514  reg_class_t, (reg_class_t rclass),
2515  default_preferred_rename_class)
2516
2517 /* This target hook allows the backend to perform additional
2518    processing while initializing for variable expansion.  */
2519 DEFHOOK
2520 (expand_to_rtl_hook,
2521  "",
2522  void, (void),
2523  hook_void_void)
2524
2525 /* This target hook allows the backend to perform additional
2526    instantiations on rtx that are not actually in insns yet,
2527    but will be later.  */
2528 DEFHOOK
2529 (instantiate_decls,
2530  "",
2531  void, (void),
2532  hook_void_void)
2533
2534 /* Return true if is OK to use a hard register REGNO as scratch register
2535    in peephole2.  */
2536 DEFHOOK
2537 (hard_regno_scratch_ok,
2538  "",
2539  bool, (unsigned int regno),
2540  default_hard_regno_scratch_ok)
2541
2542 /* Return the smallest number of different values for which it is best to
2543    use a jump-table instead of a tree of conditional branches.  */
2544 DEFHOOK
2545 (case_values_threshold,
2546  "",
2547  unsigned int, (void),
2548  default_case_values_threshold)
2549
2550 /* Retutn true if a function must have and use a frame pointer.  */
2551 DEFHOOK
2552 (frame_pointer_required,
2553  "",
2554  bool, (void),
2555  hook_bool_void_false)
2556
2557 /* Returns true if the compiler is allowed to try to replace register number
2558    from-reg with register number to-reg.  */
2559 DEFHOOK
2560 (can_eliminate,
2561  "",
2562  bool, (const int from_reg, const int to_reg),
2563  hook_bool_const_int_const_int_true)
2564
2565 /* Modify any or all of fixed_regs, call_used_regs, global_regs,
2566    reg_names, and reg_class_contents to account of the vagaries of the
2567    target.  */
2568 DEFHOOK
2569 (conditional_register_usage,
2570  "",
2571  void, (void),
2572  hook_void_void)
2573
2574 /* Functions specific to the C family of frontends.  */
2575 #undef HOOK_PREFIX
2576 #define HOOK_PREFIX "TARGET_C_"
2577 HOOK_VECTOR (TARGET_C, c)
2578
2579 /* ??? Documenting this hook requires a GFDL license grant.  */
2580 DEFHOOK_UNDOC
2581 (mode_for_suffix,
2582 "Return machine mode for non-standard constant literal suffix @var{c},\
2583  or VOIDmode if non-standard suffixes are unsupported.",
2584  enum machine_mode, (char c),
2585  default_mode_for_suffix)
2586
2587 HOOK_VECTOR_END (c)
2588
2589 /* Functions specific to the C++ frontend.  */
2590 #undef HOOK_PREFIX
2591 #define HOOK_PREFIX "TARGET_CXX_"
2592 HOOK_VECTOR (TARGET_CXX, cxx)
2593
2594 /* Return the integer type used for guard variables.  */
2595 DEFHOOK
2596 (guard_type,
2597  "",
2598  tree, (void),
2599  default_cxx_guard_type)
2600
2601 /* Return true if only the low bit of the guard should be tested.  */
2602 DEFHOOK
2603 (guard_mask_bit,
2604  "",
2605  bool, (void),
2606  hook_bool_void_false)
2607
2608 /* Returns the size of the array cookie for an array of type.  */
2609 DEFHOOK
2610 (get_cookie_size,
2611  "",
2612  tree, (tree type),
2613  default_cxx_get_cookie_size)
2614
2615 /* Returns true if the element size should be stored in the array cookie.  */
2616 DEFHOOK
2617 (cookie_has_size,
2618  "",
2619  bool, (void),
2620  hook_bool_void_false)
2621
2622 /* Allows backends to perform additional processing when
2623    deciding if a class should be exported or imported.  */
2624 DEFHOOK
2625 (import_export_class,
2626  "",
2627  int, (tree type, int import_export), NULL)
2628
2629 /* Returns true if constructors and destructors return "this".  */
2630 DEFHOOK
2631 (cdtor_returns_this,
2632  "",
2633  bool, (void),
2634  hook_bool_void_false)
2635
2636 /* Returns true if the key method for a class can be an inline
2637    function, so long as it is not declared inline in the class
2638    itself.  Returning true is the behavior required by the Itanium C++ ABI.  */
2639 DEFHOOK
2640 (key_method_may_be_inline,
2641  "",
2642  bool, (void),
2643  hook_bool_void_true)
2644
2645 DEFHOOK
2646 (determine_class_data_visibility,
2647 "@var{decl} is a virtual table, virtual table table, typeinfo object,\
2648  or other similar implicit class data object that will be emitted with\
2649  external linkage in this translation unit.  No ELF visibility has been\
2650  explicitly specified.  If the target needs to specify a visibility\
2651  other than that of the containing class, use this hook to set\
2652  @code{DECL_VISIBILITY} and @code{DECL_VISIBILITY_SPECIFIED}.",
2653  void, (tree decl),
2654  hook_void_tree)
2655
2656 /* Returns true (the default) if virtual tables and other
2657    similar implicit class data objects are always COMDAT if they
2658    have external linkage.  If this hook returns false, then
2659    class data for classes whose virtual table will be emitted in
2660    only one translation unit will not be COMDAT.  */
2661 DEFHOOK
2662 (class_data_always_comdat,
2663  "",
2664  bool, (void),
2665  hook_bool_void_true)
2666
2667 /* Returns true (the default) if the RTTI for the basic types,
2668    which is always defined in the C++ runtime, should be COMDAT;
2669    false if it should not be COMDAT.  */
2670 DEFHOOK
2671 (library_rtti_comdat,
2672  "",
2673  bool, (void),
2674  hook_bool_void_true)
2675
2676 /* Returns true if __aeabi_atexit should be used to register static
2677    destructors.  */
2678 DEFHOOK
2679 (use_aeabi_atexit,
2680  "",
2681  bool, (void),
2682  hook_bool_void_false)
2683
2684 /* Returns true if target may use atexit in the same manner as
2685    __cxa_atexit  to register static destructors.  */
2686 DEFHOOK
2687 (use_atexit_for_cxa_atexit,
2688  "",
2689  bool, (void),
2690  hook_bool_void_false)
2691
2692 DEFHOOK
2693 (adjust_class_at_definition,
2694 "@var{type} is a C++ class (i.e., RECORD_TYPE or UNION_TYPE) that has just\
2695  been defined.  Use this hook to make adjustments to the class (eg, tweak\
2696  visibility or perform any other required target modifications).",
2697  void, (tree type),
2698  hook_void_tree)
2699
2700 DEFHOOK
2701 (decl_mangling_context,
2702  "Return target-specific mangling context of @var{decl} or @code{NULL_TREE}.",
2703  tree, (const_tree decl),
2704  hook_tree_const_tree_null)
2705
2706 HOOK_VECTOR_END (cxx)
2707
2708 /* Functions and data for emulated TLS support.  */
2709 #undef HOOK_PREFIX
2710 #define HOOK_PREFIX "TARGET_EMUTLS_"
2711 HOOK_VECTOR (TARGET_EMUTLS, emutls)
2712
2713 /* Name of the address and common functions.  */
2714 DEFHOOKPOD
2715 (get_address,
2716  "",
2717  const char *, "__builtin___emutls_get_address")
2718
2719 DEFHOOKPOD
2720 (register_common,
2721  "",
2722  const char *, "__builtin___emutls_register_common")
2723
2724 /* Prefixes for proxy variable and template.  */
2725 DEFHOOKPOD
2726 (var_section,
2727  "",
2728  const char *, NULL)
2729
2730 DEFHOOKPOD
2731 (tmpl_section,
2732  "",
2733  const char *, NULL)
2734
2735 /* Prefixes for proxy variable and template.  */
2736 DEFHOOKPOD
2737 (var_prefix,
2738  "",
2739  const char *, NULL)
2740
2741 DEFHOOKPOD
2742 (tmpl_prefix,
2743  "",
2744  const char *, NULL)
2745
2746 /* Function to generate field definitions of the proxy variable.  */
2747 DEFHOOK
2748 (var_fields,
2749  "",
2750  tree, (tree type, tree *name),
2751  default_emutls_var_fields)
2752
2753 /* Function to initialize a proxy variable.  */
2754 DEFHOOK
2755 (var_init,
2756  "",
2757  tree, (tree var, tree decl, tree tmpl_addr),
2758  default_emutls_var_init)
2759
2760 /* Whether we are allowed to alter the usual alignment of the
2761    proxy variable.  */
2762 DEFHOOKPOD
2763 (var_align_fixed,
2764  "",
2765  bool, false)
2766
2767 /* Whether we can emit debug information for TLS vars.  */
2768 DEFHOOKPOD
2769 (debug_form_tls_address,
2770  "",
2771  bool, false)
2772
2773 HOOK_VECTOR_END (emutls)
2774
2775 #undef HOOK_PREFIX
2776 #define HOOK_PREFIX "TARGET_OPTION_"
2777 HOOK_VECTOR (TARGET_OPTION_HOOKS, target_option_hooks)
2778
2779 /* Function to validate the attribute((option(...))) strings or NULL.  If
2780    the option is validated, it is assumed that DECL_FUNCTION_SPECIFIC will
2781    be filled in in the function decl node.  */
2782 DEFHOOK
2783 (valid_attribute_p,
2784  "",
2785  bool, (tree fndecl, tree name, tree args, int flags),
2786  default_target_option_valid_attribute_p)
2787
2788 /* Function to save any extra target state in the target options structure.  */
2789 DEFHOOK
2790 (save,
2791  "",
2792  void, (struct cl_target_option *ptr), NULL)
2793
2794 /* Function to restore any extra target state from the target options
2795    structure.  */
2796 DEFHOOK
2797 (restore,
2798  "",
2799  void, (struct cl_target_option *ptr), NULL)
2800
2801 /* Function to print any extra target state from the target options
2802    structure.  */
2803 DEFHOOK
2804 (print,
2805  "",
2806  void, (FILE *file, int indent, struct cl_target_option *ptr), NULL)
2807
2808 /* Function to parse arguments to be validated for #pragma option, and to
2809    change the state if the options are valid.  If the first argument is
2810    NULL, the second argument specifies the default options to use.  Return
2811    true if the options are valid, and set the current state.  */
2812 /* ??? The documentation in tm.texi is incomplete.  */
2813 DEFHOOK
2814 (pragma_parse,
2815  "",
2816  bool, (tree args, tree pop_target),
2817  default_target_option_pragma_parse)
2818
2819 /* Do option overrides for the target.  */
2820 DEFHOOK
2821 (override,
2822  "",
2823  void, (void),
2824  hook_void_void)
2825
2826 /* This function returns true if DECL1 and DECL2 are versions of the same
2827    function.  DECL1 and DECL2 are function versions if and only if they
2828    have the same function signature and different target specific attributes,
2829    that is, they are compiled for different target machines.  */
2830 DEFHOOK
2831 (function_versions,
2832  "",
2833  bool, (tree decl1, tree decl2),
2834  hook_bool_tree_tree_false)
2835
2836 /* This function returns true if the target supports function
2837    multiversioning.  */
2838 DEFHOOK
2839 (supports_function_versions,
2840  "",
2841  bool, (void),
2842  hook_bool_void_false)
2843
2844 /* Function to determine if one function can inline another function.  */
2845 #undef HOOK_PREFIX
2846 #define HOOK_PREFIX "TARGET_"
2847 DEFHOOK
2848 (can_inline_p,
2849  "",
2850  bool, (tree caller, tree callee),
2851  default_target_can_inline_p)
2852
2853 HOOK_VECTOR_END (target_option)
2854
2855 /* For targets that need to mark extra registers as live on entry to
2856    the function, they should define this target hook and set their
2857    bits in the bitmap passed in. */
2858 DEFHOOK
2859 (extra_live_on_entry,
2860  "",
2861  void, (bitmap regs),
2862  hook_void_bitmap)
2863
2864 /* Fill in additional registers set up by prologue into a regset.  */
2865 DEFHOOK
2866 (set_up_by_prologue,
2867  "This hook should add additional registers that are computed by the prologue\
2868  to the hard regset for shrink-wrapping optimization purposes.",
2869  void, (struct hard_reg_set_container *),
2870  NULL)
2871
2872 /* For targets that have attributes that can affect whether a
2873    function's return statements need checking.  For instance a 'naked'
2874    function attribute.  */
2875 DEFHOOK
2876 (warn_func_return,
2877  "True if a function's return statements should be checked for matching the function's return type.  This includes checking for falling off the end of a non-void function.  Return false if no such check should be made.",
2878  bool, (tree),
2879  hook_bool_tree_true)
2880
2881 /* Determine the type of unwind info to emit for debugging.  */
2882 DEFHOOK
2883 (debug_unwind_info,
2884  "",
2885  enum unwind_info_type, (void),
2886  default_debug_unwind_info)
2887
2888 /* The code parameter should be of type enum rtx_code but this is not
2889    defined at this time.  */
2890 DEFHOOK
2891 (canonicalize_comparison,
2892  "",
2893  void, (int *code, rtx *op0, rtx *op1, bool op0_preserve_value),
2894  default_canonicalize_comparison)
2895
2896 DEFHOOKPOD
2897 (atomic_test_and_set_trueval,
2898  "This value should be set if the result written by\
2899  @code{atomic_test_and_set} is not exactly 1, i.e. the\
2900  @code{bool} @code{true}.",
2901  unsigned char, 1)
2902
2903 /* Leave the boolean fields at the end.  */
2904
2905 /* True if we can create zeroed data by switching to a BSS section
2906    and then using ASM_OUTPUT_SKIP to allocate the space.  */
2907 DEFHOOKPOD
2908 (have_switchable_bss_sections,
2909  "",
2910  bool, false)
2911
2912 /* True if "native" constructors and destructors are supported,
2913    false if we're using collect2 for the job.  */
2914 DEFHOOKPOD
2915 (have_ctors_dtors,
2916  "",
2917  bool, false)
2918
2919 /* True if thread-local storage is supported.  */
2920 DEFHOOKPOD
2921 (have_tls,
2922  "",
2923  bool, false)
2924
2925 /* True if a small readonly data section is supported.  */
2926 DEFHOOKPOD
2927 (have_srodata_section,
2928  "",
2929  bool, false)
2930
2931 /* True if EH frame info sections should be zero-terminated.  */
2932 DEFHOOKPOD
2933 (terminate_dw2_eh_frame_info,
2934  "",
2935  bool, true)
2936
2937 /* True if #NO_APP should be emitted at the beginning of assembly output.  */
2938 DEFHOOKPOD
2939 (asm_file_start_app_off,
2940  "",
2941  bool, false)
2942
2943 /* True if output_file_directive should be called for main_input_filename
2944    at the beginning of assembly output.  */
2945 DEFHOOKPOD
2946 (asm_file_start_file_directive,
2947  "",
2948  bool, false)
2949
2950 /* True if the target is allowed to reorder memory accesses unless
2951    synchronization is explicitly requested.  */
2952 DEFHOOKPOD
2953 (relaxed_ordering,
2954  "",
2955  bool, false)
2956
2957 /* Returns true if we should generate exception tables for use with the
2958    ARM EABI.  The effects the encoding of function exception specifications.  */
2959 DEFHOOKPOD
2960 (arm_eabi_unwinder,
2961  "",
2962  bool, false)
2963
2964 DEFHOOKPOD
2965 (want_debug_pub_sections,
2966  "True if the @code{.debug_pubtypes} and @code{.debug_pubnames} sections\
2967  should be emitted.  These sections are not used on most platforms, and\
2968  in particular GDB does not use them.",
2969  bool, false)
2970
2971 DEFHOOKPOD
2972 (force_at_comp_dir,
2973  "True if the @code{DW_AT_comp_dir} attribute should be emitted for each \
2974  compilation unit.  This attribute is required for the darwin linker \
2975  to emit debug information.",
2976  bool, false)
2977
2978 DEFHOOKPOD
2979 (delay_sched2, "True if sched2 is not to be run at its normal place.  \
2980 This usually means it will be run as part of machine-specific reorg.",
2981 bool, false)
2982
2983 DEFHOOKPOD
2984 (delay_vartrack, "True if vartrack is not to be run at its normal place.  \
2985 This usually means it will be run as part of machine-specific reorg.",
2986 bool, false)
2987
2988 /* Leave the boolean fields at the end.  */
2989
2990 /* Close the 'struct gcc_target' definition.  */
2991 HOOK_VECTOR_END (C90_EMPTY_HACK)