xref: /dragonfly/contrib/gcc-4.7/gcc/target.def (revision d4ef6694)
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
31HOOK_VECTOR (TARGET_INITIALIZER, gcc_target)
32
33/* Functions that output assembler for the target.  */
34#define HOOK_PREFIX "TARGET_ASM_"
35HOOK_VECTOR (TARGET_ASM_OUT, asm_out)
36
37/* Opening and closing parentheses for asm expression grouping.  */
38DEFHOOKPOD
39(open_paren,
40 "",
41 const char *, "(")
42DEFHOOKPODX (close_paren, const char *, ")")
43
44/* Assembler instructions for creating various kinds of integer object.  */
45DEFHOOKPOD
46(byte_op,
47 "",
48 const char *, "\t.byte\t")
49DEFHOOKPOD (aligned_op, "*", struct asm_int_op, TARGET_ASM_ALIGNED_INT_OP)
50DEFHOOKPOD (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.  */
54DEFHOOK
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.  */
62DEFHOOK
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.  */
70DEFHOOK
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.  */
78DEFHOOK
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.  */
89DEFHOOK
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.  */
98DEFHOOK
99(globalize_label,
100 "",
101 void, (FILE *stream, const char *name),
102 default_globalize_label)
103
104/* Output code that will globalize a declaration.  */
105DEFHOOK
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.  */
115DEFHOOK
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.  */
122DEFHOOK
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.  */
129DEFHOOK
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.  */
138DEFHOOK
139(unwind_emit,
140 "",
141 void, (FILE *stream, rtx insn),
142 NULL)
143
144DEFHOOKPOD
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.  */
153DEFHOOK_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.  */
160DEFHOOK
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.  */
167DEFHOOK
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.  */
174DEFHOOK
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.  */
182DEFHOOK
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.  */
189DEFHOOK
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.  */
196DEFHOOK
197(function_end_prologue,
198 "",
199 void, (FILE *file),
200 no_asm_to_stream)
201
202/* Output the assembler code for start of epilogue.  */
203DEFHOOK
204(function_begin_epilogue,
205 "",
206 void, (FILE *file),
207 no_asm_to_stream)
208
209/* Output the assembler code for function exit.  */
210DEFHOOK
211(function_epilogue,
212 "",
213 void, (FILE *file, HOST_WIDE_INT size),
214 default_function_pro_epilogue)
215
216/* Initialize target-specific sections.  */
217DEFHOOK
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.  */
226DEFHOOK
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.  */
239DEFHOOK
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.  */
246DEFHOOK
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.  */
260DEFHOOK
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.  */
270DEFHOOK
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.  */
278DEFHOOK
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.  */
286DEFHOOK
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.  */
293DEFHOOK
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.  */
301DEFHOOKPOD
302(mergeable_rodata_prefix,
303 "Usually, the compiler uses the prefix @code{\".rodata\"} to construct\n\
304section names for mergeable constant data.  Define this macro to override\n\
305the 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.  */
309DEFHOOK
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.  */
316DEFHOOK
317(constructor,
318 "",
319 void, (rtx symbol, int priority), NULL)
320
321/* Output a destructor for a symbol with a given priority.  */
322DEFHOOK
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.  */
332DEFHOOK
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.  */
345DEFHOOK
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.  */
354DEFHOOK
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.  */
361DEFHOOK
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.  */
369DEFHOOK
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.  */
377DEFHOOK
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.  */
385DEFHOOK
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.  */
393DEFHOOK
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.  */
401DEFHOOK
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.  */
408DEFHOOK
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.  */
418DEFHOOKPOD
419(record_gcc_switches_section,
420 "",
421 const char *, ".GCC.command.line")
422
423/* Output the definition of a section anchor.  */
424DEFHOOK
425(output_anchor,
426 "",
427 void, (rtx x),
428 default_asm_output_anchor)
429
430/* Output a DTP-relative reference to a TLS symbol.  */
431DEFHOOK
432(output_dwarf_dtprel,
433 "",
434 void, (FILE *file, int size, rtx x),
435 NULL)
436
437/* Some target machines need to postscan each insn after it is output.  */
438DEFHOOK
439(final_postscan_insn,
440 "",
441 void, (FILE *file, rtx insn, rtx *opvec, int noperands),
442 NULL)
443
444/* Emit the trampoline template.  This hook may be NULL.  */
445DEFHOOK
446(trampoline_template,
447 "",
448 void, (FILE *f),
449 NULL)
450
451DEFHOOK
452(output_source_filename,
453 "Output COFF information or DWARF debugging information which indicates\
454 that filename @var{name} is the current source file to the stdio\
455 stream @var{file}.\n\
456 \n\
457 This target hook need not be defined if the standard form of output\
458 for the file format in use is appropriate.",
459 void ,(FILE *file, const char *name),
460 default_asm_output_source_filename)
461
462DEFHOOK
463(output_addr_const_extra,
464 "",
465 bool, (FILE *file, rtx x),
466 hook_bool_FILEptr_rtx_false)
467
468/* ??? The TARGET_PRINT_OPERAND* hooks are part of the asm_out struct,
469   even though that is not reflected in the macro name to override their
470   initializers.  */
471#undef HOOK_PREFIX
472#define HOOK_PREFIX "TARGET_"
473
474/* Emit a machine-specific insn operand.  */
475/* ??? tm.texi only documents the old macro PRINT_OPERAND,
476   not this  hook, and uses a different name for the argument FILE.  */
477DEFHOOK_UNDOC
478(print_operand,
479 "",
480 void, (FILE *file, rtx x, int code),
481 default_print_operand)
482
483/* Emit a machine-specific memory address.  */
484/* ??? tm.texi only documents the old macro PRINT_OPERAND_ADDRESS,
485   not this  hook, and uses different argument names.  */
486DEFHOOK_UNDOC
487(print_operand_address,
488 "",
489 void, (FILE *file, rtx addr),
490 default_print_operand_address)
491
492/* Determine whether CODE is a valid punctuation character for the
493   `print_operand' hook.  */
494/* ??? tm.texi only documents the old macro PRINT_OPERAND_PUNCT_VALID_P,
495   not this  hook.  */
496DEFHOOK_UNDOC
497(print_operand_punct_valid_p,
498 "",
499 bool ,(unsigned char code),
500 default_print_operand_punct_valid_p)
501
502/* Given a symbol name, perform same mangling as assemble_name and
503   ASM_OUTPUT_LABELREF, returning result as an IDENTIFIER_NODE.  */
504DEFHOOK
505(mangle_assembler_name,
506 "Given a symbol @var{name}, perform same mangling as @code{varasm.c}'s\
507 @code{assemble_name}, but in memory rather than to a file stream, returning\
508 result as an @code{IDENTIFIER_NODE}.  Required for correct LTO symtabs.  The\
509 default implementation calls the @code{TARGET_STRIP_NAME_ENCODING} hook and\
510 then prepends the @code{USER_LABEL_PREFIX}, if any.",
511 tree, (const char *name),
512 default_mangle_assembler_name)
513
514HOOK_VECTOR_END (asm_out)
515
516/* Functions relating to instruction scheduling.  All of these
517   default to null pointers, which haifa-sched.c looks for and handles.  */
518#undef HOOK_PREFIX
519#define HOOK_PREFIX "TARGET_SCHED_"
520HOOK_VECTOR (TARGET_SCHED, sched)
521
522/* Given the current cost, COST, of an insn, INSN, calculate and
523   return a new cost based on its relationship to DEP_INSN through
524   the dependence LINK.  The default is to make no adjustment.  */
525DEFHOOK
526(adjust_cost,
527 "",
528 int, (rtx insn, rtx link, rtx dep_insn, int cost), NULL)
529
530/* Adjust the priority of an insn as you see fit.  Returns the new priority.  */
531DEFHOOK
532(adjust_priority,
533 "",
534 int, (rtx insn, int priority), NULL)
535
536/* Function which returns the maximum number of insns that can be
537   scheduled in the same machine cycle.  This must be constant
538   over an entire compilation.  The default is 1.  */
539DEFHOOK
540(issue_rate,
541 "",
542 int, (void), NULL)
543
544/* Calculate how much this insn affects how many more insns we
545   can emit this cycle.  Default is they all cost the same.  */
546DEFHOOK
547(variable_issue,
548 "",
549 int, (FILE *file, int verbose, rtx insn, int more), NULL)
550
551/* Initialize machine-dependent scheduling code.  */
552DEFHOOK
553(init,
554 "",
555 void, (FILE *file, int verbose, int max_ready), NULL)
556
557/* Finalize machine-dependent scheduling code.  */
558DEFHOOK
559(finish,
560 "",
561 void, (FILE *file, int verbose), NULL)
562
563 /* Initialize machine-dependent function wide scheduling code.  */
564DEFHOOK
565(init_global,
566 "",
567 void, (FILE *file, int verbose, int old_max_uid), NULL)
568
569/* Finalize machine-dependent function wide scheduling code.  */
570DEFHOOK
571(finish_global,
572 "",
573 void, (FILE *file, int verbose), NULL)
574
575/* Reorder insns in a machine-dependent fashion, in two different
576       places.  Default does nothing.  */
577DEFHOOK
578(reorder,
579 "",
580 int, (FILE *file, int verbose, rtx *ready, int *n_readyp, int clock), NULL)
581
582DEFHOOK
583(reorder2,
584 "",
585 int, (FILE *file, int verbose, rtx *ready, int *n_readyp, int clock), NULL)
586
587/* The following member value is a pointer to a function called
588   after evaluation forward dependencies of insns in chain given
589   by two parameter values (head and tail correspondingly).  */
590DEFHOOK
591(dependencies_evaluation_hook,
592 "",
593 void, (rtx head, rtx tail), NULL)
594
595/* The values of the following four members are pointers to functions
596   used to simplify the automaton descriptions.  dfa_pre_cycle_insn and
597   dfa_post_cycle_insn give functions returning insns which are used to
598   change the pipeline hazard recognizer state when the new simulated
599   processor cycle correspondingly starts and finishes.  The function
600   defined by init_dfa_pre_cycle_insn and init_dfa_post_cycle_insn are
601   used to initialize the corresponding insns.  The default values of
602   the members result in not changing the automaton state when the
603   new simulated processor cycle correspondingly starts and finishes.  */
604
605DEFHOOK
606(init_dfa_pre_cycle_insn,
607 "",
608 void, (void), NULL)
609
610DEFHOOK
611(dfa_pre_cycle_insn,
612 "",
613 rtx, (void), NULL)
614
615DEFHOOK
616(init_dfa_post_cycle_insn,
617 "",
618 void, (void), NULL)
619
620DEFHOOK
621(dfa_post_cycle_insn,
622 "",
623 rtx, (void), NULL)
624
625/* The values of the following two members are pointers to
626   functions used to simplify the automaton descriptions.
627   dfa_pre_advance_cycle and dfa_post_advance_cycle are getting called
628   immediately before and after cycle is advanced.  */
629
630DEFHOOK
631(dfa_pre_advance_cycle,
632 "",
633 void, (void), NULL)
634
635DEFHOOK
636(dfa_post_advance_cycle,
637 "",
638 void, (void), NULL)
639
640/* The following member value is a pointer to a function returning value
641   which defines how many insns in queue `ready' will we try for
642   multi-pass scheduling.  If the member value is nonzero and the
643   function returns positive value, the DFA based scheduler will make
644   multi-pass scheduling for the first cycle.  In other words, we will
645   try to choose ready insn which permits to start maximum number of
646   insns on the same cycle.  */
647DEFHOOK
648(first_cycle_multipass_dfa_lookahead,
649 "",
650 int, (void), NULL)
651
652/* The following member value is pointer to a function controlling
653   what insns from the ready insn queue will be considered for the
654   multipass insn scheduling.  If the hook returns zero for insn
655   passed as the parameter, the insn will be not chosen to be issued.  */
656DEFHOOK
657(first_cycle_multipass_dfa_lookahead_guard,
658 "",
659 int, (rtx insn), NULL)
660
661/* This hook prepares the target for a new round of multipass
662   scheduling.
663   DATA is a pointer to target-specific data used for multipass scheduling.
664   READY_TRY and N_READY represent the current state of search in the
665   optimization space.  The target can filter out instructions that
666   should not be tried during current round by setting corresponding
667   elements in READY_TRY to non-zero.
668   FIRST_CYCLE_INSN_P is true if this is the first round of multipass
669   scheduling on current cycle.  */
670DEFHOOK
671(first_cycle_multipass_begin,
672 "",
673 void, (void *data, char *ready_try, int n_ready, bool first_cycle_insn_p),
674 NULL)
675
676/* This hook is called when multipass scheduling evaluates instruction INSN.
677   DATA is a pointer to target-specific data that can be used to record effects
678   of INSN on CPU that are not described in DFA.
679   READY_TRY and N_READY represent the current state of search in the
680   optimization space.  The target can filter out instructions that
681   should not be tried after issueing INSN by setting corresponding
682   elements in READY_TRY to non-zero.
683   INSN is the instruction being evaluated.
684   PREV_DATA is a pointer to target-specific data corresponding
685   to a state before issueing INSN.  */
686DEFHOOK
687(first_cycle_multipass_issue,
688 "",
689 void, (void *data, char *ready_try, int n_ready, rtx insn,
690	const void *prev_data), NULL)
691
692/* This hook is called when multipass scheduling backtracks from evaluation of
693   instruction corresponding to DATA.
694   DATA is a pointer to target-specific data that stores the effects
695   of instruction from which the algorithm backtracks on CPU that are not
696   described in DFA.
697   READY_TRY and N_READY represent the current state of search in the
698   optimization space.  The target can filter out instructions that
699   should not be tried after issueing INSN by setting corresponding
700   elements in READY_TRY to non-zero.  */
701DEFHOOK
702(first_cycle_multipass_backtrack,
703 "",
704 void, (const void *data, char *ready_try, int n_ready), NULL)
705
706/* This hook notifies the target about the result of the concluded current
707   round of multipass scheduling.
708   DATA is a pointer.
709   If DATA is non-NULL it points to target-specific data used for multipass
710   scheduling which corresponds to instruction at the start of the chain of
711   the winning solution.  DATA is NULL when multipass scheduling cannot find
712   a good enough solution on current cycle and decides to retry later,
713   usually after advancing the cycle count.  */
714DEFHOOK
715(first_cycle_multipass_end,
716 "",
717 void, (const void *data), NULL)
718
719/* This hook is called to initialize target-specific data for multipass
720   scheduling after it has been allocated.
721   DATA is a pointer to target-specific data that stores the effects
722   of instruction from which the algorithm backtracks on CPU that are not
723   described in DFA.  */
724DEFHOOK
725(first_cycle_multipass_init,
726 "",
727 void, (void *data), NULL)
728
729/* This hook is called to finalize target-specific data for multipass
730   scheduling before it is deallocated.
731   DATA is a pointer to target-specific data that stores the effects
732   of instruction from which the algorithm backtracks on CPU that are not
733   described in DFA.  */
734DEFHOOK
735(first_cycle_multipass_fini,
736 "",
737 void, (void *data), NULL)
738
739/* The following member value is pointer to a function called by
740   the insn scheduler before issuing insn passed as the third
741   parameter on given cycle.  If the hook returns nonzero, the
742   insn is not issued on given processors cycle.  Instead of that,
743   the processor cycle is advanced.  If the value passed through
744   the last parameter is zero, the insn ready queue is not sorted
745   on the new cycle start as usually.  The first parameter passes
746   file for debugging output.  The second one passes the scheduler
747   verbose level of the debugging output.  The forth and the fifth
748   parameter values are correspondingly processor cycle on which
749   the previous insn has been issued and the current processor cycle.  */
750DEFHOOK
751(dfa_new_cycle,
752 "",
753 int, (FILE *dump, int verbose, rtx insn, int last_clock,
754       int clock, int *sort_p),
755 NULL)
756
757/* The following member value is a pointer to a function called by the
758   insn scheduler.  It should return true if there exists a dependence
759   which is considered costly by the target, between the insn
760   DEP_PRO (&_DEP), and the insn DEP_CON (&_DEP).  The first parameter is
761   the dep that represents the dependence between the two insns.  The
762   second argument is the cost of the dependence as estimated by
763   the scheduler.  The last argument is the distance in cycles
764   between the already scheduled insn (first parameter) and the
765   second insn (second parameter).  */
766DEFHOOK
767(is_costly_dependence,
768 "",
769 bool, (struct _dep *_dep, int cost, int distance), NULL)
770
771DEFHOOK_UNDOC
772(adjust_cost_2,
773 "Given the current cost, @var{cost}, of an insn, @var{insn}, calculate and\
774 return a new cost based on its relationship to @var{dep_insn} through the\
775 dependence of weakness @var{dw}.  The default is to make no adjustment.",
776 int, (rtx insn, int dep_type1, rtx dep_insn, int cost, int dw), NULL)
777
778/* The following member value is a pointer to a function called
779   by the insn scheduler. This hook is called to notify the backend
780   that new instructions were emitted.  */
781DEFHOOK
782(h_i_d_extended,
783 "",
784 void, (void), NULL)
785
786/* Next 5 functions are for multi-point scheduling.  */
787
788/* Allocate memory for scheduler context.  */
789DEFHOOK
790(alloc_sched_context,
791 "",
792 void *, (void), NULL)
793
794/* Fills the context from the local machine scheduler context.  */
795DEFHOOK
796(init_sched_context,
797 "",
798 void, (void *tc, bool clean_p), NULL)
799
800/* Sets local machine scheduler context to a saved value.  */
801DEFHOOK
802(set_sched_context,
803 "",
804 void, (void *tc), NULL)
805
806/* Clears a scheduler context so it becomes like after init.  */
807DEFHOOK
808(clear_sched_context,
809 "",
810 void, (void *tc), NULL)
811
812/* Frees the scheduler context.  */
813DEFHOOK
814(free_sched_context,
815 "",
816 void, (void *tc), NULL)
817
818/* The following member value is a pointer to a function called
819   by the insn scheduler.
820   The first parameter is an instruction, the second parameter is the type
821   of the requested speculation, and the third parameter is a pointer to the
822   speculative pattern of the corresponding type (set if return value == 1).
823   It should return
824   -1, if there is no pattern, that will satisfy the requested speculation type,
825   0, if current pattern satisfies the requested speculation type,
826   1, if pattern of the instruction should be changed to the newly
827   generated one.  */
828DEFHOOK
829(speculate_insn,
830 "",
831 int, (rtx insn, int request, rtx *new_pat), NULL)
832
833/* The following member value is a pointer to a function called
834   by the insn scheduler.  It should return true if the check instruction
835   passed as the parameter needs a recovery block.  */
836DEFHOOK
837(needs_block_p,
838 "",
839 bool, (int dep_status), NULL)
840
841/* The following member value is a pointer to a function called
842   by the insn scheduler.  It should return a pattern for the check
843   instruction.
844   The first parameter is a speculative instruction, the second parameter
845   is the label of the corresponding recovery block (or null, if it is a
846   simple check).  If the mutation of the check is requested (e.g. from
847   ld.c to chk.a), the third parameter is true - in this case the first
848   parameter is the previous check.  */
849DEFHOOK
850(gen_spec_check,
851 "",
852 rtx, (rtx insn, rtx label, int mutate_p), NULL)
853
854/* The following member value is a pointer to a function controlling
855   what insns from the ready insn queue will be considered for the
856   multipass insn scheduling.  If the hook returns zero for the insn
857   passed as the parameter, the insn will not be chosen to be
858   issued.  This hook is used to discard speculative instructions,
859   that stand at the first position of the ready list.  */
860DEFHOOK
861(first_cycle_multipass_dfa_lookahead_guard_spec,
862 "",
863 bool, (const_rtx insn), NULL)
864
865/* The following member value is a pointer to a function that provides
866   information about the speculation capabilities of the target.
867   The parameter is a pointer to spec_info variable.  */
868DEFHOOK
869(set_sched_flags,
870 "",
871 void, (struct spec_info_def *spec_info), NULL)
872
873DEFHOOK_UNDOC
874(get_insn_spec_ds,
875 "Return speculation types of instruction @var{insn}.",
876 int, (rtx insn), NULL)
877
878DEFHOOK_UNDOC
879(get_insn_checked_ds,
880 "Return speculation types that are checked for instruction @var{insn}",
881 int, (rtx insn), NULL)
882
883DEFHOOK_UNDOC
884(skip_rtx_p,
885 "Return bool if rtx scanning should just skip current layer and\
886 advance to the inner rtxes.",
887 bool, (const_rtx x), NULL)
888
889/* The following member value is a pointer to a function that provides
890   information about the target resource-based lower bound which is
891   used by the swing modulo scheduler.  The parameter is a pointer
892   to ddg variable.  */
893DEFHOOK
894(sms_res_mii,
895 "",
896 int, (struct ddg *g), NULL)
897
898/* The following member value is a function that initializes dispatch
899   schedling and adds instructions to dispatch window according to its
900   parameters.  */
901DEFHOOK
902(dispatch_do,
903"",
904void, (rtx insn, int x),
905hook_void_rtx_int)
906
907/* The following member value is a a function that returns true is
908   dispatch schedling is supported in hardware and condition passed
909   as the second parameter is true.  */
910DEFHOOK
911(dispatch,
912"",
913bool, (rtx insn, int x),
914hook_bool_rtx_int_false)
915
916DEFHOOKPOD
917(exposed_pipeline,
918"True if the processor has an exposed pipeline, which means that not just\n\
919the order of instructions is important for correctness when scheduling, but\n\
920also the latencies of operations.",
921bool, false)
922
923/* The following member value is a function that returns number
924   of operations reassociator should try to put in parallel for
925   statements of the given type.  By default 1 is used.  */
926DEFHOOK
927(reassociation_width,
928"This hook is called by tree reassociator to determine a level of\n\
929parallelism required in output calculations chain.",
930int, (unsigned int opc, enum machine_mode mode),
931hook_int_uint_mode_1)
932
933HOOK_VECTOR_END (sched)
934
935/* Functions relating to vectorization.  */
936#undef HOOK_PREFIX
937#define HOOK_PREFIX "TARGET_VECTORIZE_"
938HOOK_VECTOR (TARGET_VECTORIZE, vectorize)
939
940/* The following member value is a pointer to a function called
941   by the vectorizer, and return the decl of the target builtin
942   function.  */
943DEFHOOK
944(builtin_mask_for_load,
945 "",
946 tree, (void), NULL)
947
948/* Returns a code for builtin that realizes vectorized version of
949   function, or NULL_TREE if not available.  */
950DEFHOOK
951(builtin_vectorized_function,
952 "",
953 tree, (tree fndecl, tree vec_type_out, tree vec_type_in),
954 default_builtin_vectorized_function)
955
956/* Returns a function declaration for a builtin that realizes the
957   vector conversion, or NULL_TREE if not available.  */
958DEFHOOK
959(builtin_conversion,
960 "",
961 tree, (unsigned code, tree dest_type, tree src_type),
962 default_builtin_vectorized_conversion)
963
964/* Target builtin that implements vector widening multiplication.
965   builtin_mul_widen_eve computes the element-by-element products
966   for the even elements, and builtin_mul_widen_odd computes the
967   element-by-element products for the odd elements.  */
968DEFHOOK
969(builtin_mul_widen_even,
970 "",
971 tree, (tree x), NULL)
972
973DEFHOOK
974(builtin_mul_widen_odd,
975 "",
976 tree, (tree x), NULL)
977
978/* Cost of different vector/scalar statements in vectorization cost
979   model. In case of misaligned vector loads and stores the cost depends
980   on the data type and misalignment value.  */
981DEFHOOK
982(builtin_vectorization_cost,
983 "",
984 int, (enum vect_cost_for_stmt type_of_cost, tree vectype, int misalign),
985 default_builtin_vectorization_cost)
986
987/* Return true if vector alignment is reachable (by peeling N
988   iterations) for the given type.  */
989DEFHOOK
990(vector_alignment_reachable,
991 "",
992 bool, (const_tree type, bool is_packed),
993 default_builtin_vector_alignment_reachable)
994
995/* Return true if a vector created for vec_perm_const is valid.
996   A NULL indicates that all constants are valid permutations.  */
997DEFHOOK
998(vec_perm_const_ok,
999 "",
1000 bool, (enum machine_mode, const unsigned char *sel),
1001 NULL)
1002
1003/* Return true if the target supports misaligned store/load of a
1004   specific factor denoted in the third parameter.  The last parameter
1005   is true if the access is defined in a packed struct.  */
1006DEFHOOK
1007(support_vector_misalignment,
1008 "",
1009 bool,
1010 (enum machine_mode mode, const_tree type, int misalignment, bool is_packed),
1011 default_builtin_support_vector_misalignment)
1012
1013/* Return the builtin decl needed to load a vector of TYPE.  */
1014DEFHOOK
1015(builtin_tm_load,
1016 "This hook should return the built-in decl needed to load a vector of the "
1017 "given type within a transaction.",
1018 tree,
1019 (tree),
1020 default_builtin_tm_load_store)
1021
1022/* Return the builtin decl needed to store a vector of TYPE.  */
1023DEFHOOK
1024(builtin_tm_store,
1025 "This hook should return the built-in decl needed to store a vector of the "
1026 "given type within a transaction.",
1027 tree,
1028 (tree),
1029 default_builtin_tm_load_store)
1030
1031/* Returns the preferred mode for SIMD operations for the specified
1032   scalar mode.  */
1033DEFHOOK
1034(preferred_simd_mode,
1035 "",
1036 enum machine_mode,
1037 (enum machine_mode mode),
1038 default_preferred_simd_mode)
1039
1040/* Returns a mask of vector sizes to iterate over when auto-vectorizing
1041   after processing the preferred one derived from preferred_simd_mode.  */
1042DEFHOOK
1043(autovectorize_vector_sizes,
1044 "",
1045 unsigned int,
1046 (void),
1047 default_autovectorize_vector_sizes)
1048
1049/* Target builtin that implements vector gather operation.  */
1050DEFHOOK
1051(builtin_gather,
1052 "",
1053 tree,
1054 (const_tree mem_vectype, const_tree index_type, int scale),
1055 NULL)
1056
1057HOOK_VECTOR_END (vectorize)
1058
1059#undef HOOK_PREFIX
1060#define HOOK_PREFIX "TARGET_"
1061
1062/* Allow target specific overriding of option settings after options have
1063  been changed by an attribute or pragma or when it is reset at the
1064  end of the code affected by an attribute or pragma.  */
1065DEFHOOK
1066(override_options_after_change,
1067 "",
1068 void, (void),
1069 hook_void_void)
1070
1071DEFHOOK_UNDOC
1072(eh_return_filter_mode,
1073 "Return machine mode for filter value.",
1074 enum machine_mode, (void),
1075 default_eh_return_filter_mode)
1076
1077/* Return machine mode for libgcc expanded cmp instructions.  */
1078DEFHOOK
1079(libgcc_cmp_return_mode,
1080 "",
1081 enum machine_mode, (void),
1082 default_libgcc_cmp_return_mode)
1083
1084/* Return machine mode for libgcc expanded shift instructions.  */
1085DEFHOOK
1086(libgcc_shift_count_mode,
1087 "",
1088 enum machine_mode, (void),
1089 default_libgcc_shift_count_mode)
1090
1091/* Return machine mode to be used for _Unwind_Word type.  */
1092DEFHOOK
1093(unwind_word_mode,
1094 "",
1095 enum machine_mode, (void),
1096 default_unwind_word_mode)
1097
1098/* Given two decls, merge their attributes and return the result.  */
1099DEFHOOK
1100(merge_decl_attributes,
1101 "",
1102 tree, (tree olddecl, tree newdecl),
1103 merge_decl_attributes)
1104
1105/* Given two types, merge their attributes and return the result.  */
1106DEFHOOK
1107(merge_type_attributes,
1108 "",
1109 tree, (tree type1, tree type2),
1110 merge_type_attributes)
1111
1112/* Table of machine attributes and functions to handle them.
1113   Ignored if NULL.  */
1114DEFHOOKPOD
1115(attribute_table,
1116 "",
1117 const struct attribute_spec *, NULL)
1118
1119/* Return true iff attribute NAME expects a plain identifier as its first
1120   argument.  */
1121DEFHOOK
1122(attribute_takes_identifier_p,
1123 "",
1124 bool, (const_tree name),
1125 hook_bool_const_tree_false)
1126
1127/* Return zero if the attributes on TYPE1 and TYPE2 are incompatible,
1128   one if they are compatible and two if they are nearly compatible
1129   (which causes a warning to be generated).  */
1130DEFHOOK
1131(comp_type_attributes,
1132 "",
1133 int, (const_tree type1, const_tree type2),
1134 hook_int_const_tree_const_tree_1)
1135
1136/* Assign default attributes to the newly defined TYPE.  */
1137DEFHOOK
1138(set_default_type_attributes,
1139 "",
1140 void, (tree type),
1141 hook_void_tree)
1142
1143/* Insert attributes on the newly created DECL.  */
1144DEFHOOK
1145(insert_attributes,
1146 "",
1147 void, (tree node, tree *attr_ptr),
1148 hook_void_tree_treeptr)
1149
1150/* Return true if FNDECL (which has at least one machine attribute)
1151   can be inlined despite its machine attributes, false otherwise.  */
1152DEFHOOK
1153(function_attribute_inlinable_p,
1154 "",
1155 bool, (const_tree fndecl),
1156 hook_bool_const_tree_false)
1157
1158/* Return true if bitfields in RECORD_TYPE should follow the
1159   Microsoft Visual C++ bitfield layout rules.  */
1160DEFHOOK
1161(ms_bitfield_layout_p,
1162 "",
1163 bool, (const_tree record_type),
1164 hook_bool_const_tree_false)
1165
1166/* For now this is only an interface to WORDS_BIG_ENDIAN for
1167   target-independent code like the front ends, need performance testing
1168   before switching completely to the target hook.  */
1169DEFHOOK_UNDOC
1170(words_big_endian,
1171 "",
1172 bool, (void),
1173 targhook_words_big_endian)
1174
1175/* Likewise for FLOAT_WORDS_BIG_ENDIAN.  */
1176DEFHOOK_UNDOC
1177(float_words_big_endian,
1178 "",
1179 bool, (void),
1180 targhook_float_words_big_endian)
1181
1182/* True if the target supports decimal floating point.  */
1183DEFHOOK
1184(decimal_float_supported_p,
1185 "",
1186 bool, (void),
1187 default_decimal_float_supported_p)
1188
1189/* True if the target supports fixed-point.  */
1190DEFHOOK
1191(fixed_point_supported_p,
1192 "",
1193 bool, (void),
1194 default_fixed_point_supported_p)
1195
1196/* Return true if anonymous bitfields affect structure alignment.  */
1197DEFHOOK
1198(align_anon_bitfield,
1199 "",
1200 bool, (void),
1201 hook_bool_void_false)
1202
1203/* Return true if volatile bitfields should use the narrowest type possible.
1204   Return false if they should use the container type.  */
1205DEFHOOK
1206(narrow_volatile_bitfield,
1207 "",
1208 bool, (void),
1209 hook_bool_void_false)
1210
1211/* Set up target-specific built-in functions.  */
1212DEFHOOK
1213(init_builtins,
1214 "",
1215 void, (void),
1216 hook_void_void)
1217
1218/* Initialize (if INITIALIZE_P is true) and return the target-specific
1219   built-in function decl for CODE.
1220   Return NULL if that is not possible.  Return error_mark_node if CODE
1221   is outside of the range of valid target builtin function codes.  */
1222DEFHOOK
1223(builtin_decl,
1224 "",
1225 tree, (unsigned code, bool initialize_p), NULL)
1226
1227/* Expand a target-specific builtin.  */
1228DEFHOOK
1229(expand_builtin,
1230 "",
1231 rtx,
1232 (tree exp, rtx target, rtx subtarget, enum machine_mode mode, int ignore),
1233 default_expand_builtin)
1234
1235/* Select a replacement for a target-specific builtin.  This is done
1236   *before* regular type checking, and so allows the target to
1237   implement a crude form of function overloading.  The result is a
1238   complete expression that implements the operation.  PARAMS really
1239   has type VEC(tree,gc)*, but we don't want to include tree.h here.  */
1240DEFHOOK
1241(resolve_overloaded_builtin,
1242 "",
1243 tree, (unsigned int /*location_t*/ loc, tree fndecl, void *arglist), NULL)
1244
1245/* Fold a target-specific builtin.  */
1246DEFHOOK
1247(fold_builtin,
1248 "",
1249 tree, (tree fndecl, int n_args, tree *argp, bool ignore),
1250 hook_tree_tree_int_treep_bool_null)
1251
1252/* Returns a code for a target-specific builtin that implements
1253   reciprocal of the function, or NULL_TREE if not available.  */
1254DEFHOOK
1255(builtin_reciprocal,
1256 "",
1257 tree, (unsigned fn, bool md_fn, bool sqrt),
1258 default_builtin_reciprocal)
1259
1260/* For a vendor-specific TYPE, return a pointer to a statically-allocated
1261   string containing the C++ mangling for TYPE.  In all other cases, return
1262   NULL.  */
1263DEFHOOK
1264(mangle_type,
1265 "",
1266 const char *, (const_tree type),
1267 hook_constcharptr_const_tree_null)
1268
1269/* Make any adjustments to libfunc names needed for this target.  */
1270DEFHOOK
1271(init_libfuncs,
1272 "",
1273 void, (void),
1274 hook_void_void)
1275
1276 /* Add a __gnu_ prefix to library functions rather than just __.  */
1277DEFHOOKPOD
1278(libfunc_gnu_prefix,
1279 "If false (the default), internal library routines start with two\n\
1280underscores.  If set to true, these routines start with @code{__gnu_}\n\
1281instead.  E.g., @code{__muldi3} changes to @code{__gnu_muldi3}.  This\n\
1282currently only affects functions defined in @file{libgcc2.c}.  If this\n\
1283is set to true, the @file{tm.h} file must also\n\
1284@code{#define LIBGCC2_GNU_PREFIX}.",
1285  bool, false)
1286
1287/* Given a decl, a section name, and whether the decl initializer
1288   has relocs, choose attributes for the section.  */
1289/* ??? Should be merged with SELECT_SECTION and UNIQUE_SECTION.  */
1290DEFHOOK
1291(section_type_flags,
1292 "",
1293 unsigned int, (tree decl, const char *name, int reloc),
1294 default_section_type_flags)
1295
1296/* True if new jumps cannot be created, to replace existing ones or
1297   not, at the current point in the compilation.  */
1298DEFHOOK
1299(cannot_modify_jumps_p,
1300 "",
1301 bool, (void),
1302 hook_bool_void_false)
1303
1304/* Return a register class for which branch target register
1305   optimizations should be applied.  */
1306DEFHOOK
1307(branch_target_register_class,
1308 "",
1309 reg_class_t, (void),
1310 default_branch_target_register_class)
1311
1312/* Return true if branch target register optimizations should include
1313   callee-saved registers that are not already live during the current
1314   function.  AFTER_PE_GEN is true if prologues and epilogues have
1315   already been generated.  */
1316DEFHOOK
1317(branch_target_register_callee_saved,
1318 "",
1319 bool, (bool after_prologue_epilogue_gen),
1320 hook_bool_bool_false)
1321
1322/* Return true if the target supports conditional execution.  */
1323DEFHOOK
1324(have_conditional_execution,
1325 "",
1326 bool, (void),
1327 default_have_conditional_execution)
1328
1329/* Return a new value for loop unroll size.  */
1330DEFHOOK
1331(loop_unroll_adjust,
1332 "",
1333 unsigned, (unsigned nunroll, struct loop *loop),
1334 NULL)
1335
1336/* True if X is a legitimate MODE-mode immediate operand.  */
1337DEFHOOK
1338(legitimate_constant_p,
1339 "",
1340 bool, (enum machine_mode mode, rtx x),
1341 hook_bool_mode_rtx_true)
1342
1343/* True if the constant X cannot be placed in the constant pool.  */
1344DEFHOOK
1345(cannot_force_const_mem,
1346 "",
1347 bool, (enum machine_mode mode, rtx x),
1348 hook_bool_mode_rtx_false)
1349
1350DEFHOOK_UNDOC
1351(cannot_copy_insn_p,
1352 "True if the insn @var{x} cannot be duplicated.",
1353 bool, (rtx), NULL)
1354
1355/* True if X is considered to be commutative.  */
1356DEFHOOK
1357(commutative_p,
1358 "",
1359 bool, (const_rtx x, int outer_code),
1360 hook_bool_const_rtx_commutative_p)
1361
1362/* True if ADDR is an address-expression whose effect depends
1363   on the mode of the memory reference it is used in.  */
1364DEFHOOK
1365(mode_dependent_address_p,
1366 "",
1367 bool, (const_rtx addr),
1368 default_mode_dependent_address_p)
1369
1370/* Given an invalid address X for a given machine mode, try machine-specific
1371   ways to make it legitimate.  Return X or an invalid address on failure.  */
1372DEFHOOK
1373(legitimize_address,
1374 "",
1375 rtx, (rtx x, rtx oldx, enum machine_mode mode),
1376 default_legitimize_address)
1377
1378/* Given an address RTX, undo the effects of LEGITIMIZE_ADDRESS.  */
1379DEFHOOK
1380(delegitimize_address,
1381 "",
1382 rtx, (rtx x),
1383 delegitimize_mem_from_attrs)
1384
1385/* Given an RTX, return true if it is not ok to emit it into debug info
1386   section.  */
1387DEFHOOK
1388(const_not_ok_for_debug_p,
1389 "",
1390 bool, (rtx x),
1391 hook_bool_rtx_false)
1392
1393/* Given an address RTX, say whether it is valid.  */
1394DEFHOOK
1395(legitimate_address_p,
1396 "",
1397 bool, (enum machine_mode mode, rtx x, bool strict),
1398 default_legitimate_address_p)
1399
1400/* True if the given constant can be put into an object_block.  */
1401DEFHOOK
1402(use_blocks_for_constant_p,
1403 "",
1404 bool, (enum machine_mode mode, const_rtx x),
1405 hook_bool_mode_const_rtx_false)
1406
1407/* The minimum and maximum byte offsets for anchored addresses.  */
1408DEFHOOKPOD
1409(min_anchor_offset,
1410 "",
1411 HOST_WIDE_INT, 0)
1412
1413DEFHOOKPOD
1414(max_anchor_offset,
1415 "",
1416 HOST_WIDE_INT, 0)
1417
1418/* True if section anchors can be used to access the given symbol.  */
1419DEFHOOK
1420(use_anchors_for_symbol_p,
1421 "",
1422 bool, (const_rtx x),
1423 default_use_anchors_for_symbol_p)
1424
1425/* True if it is OK to do sibling call optimization for the specified
1426   call expression EXP.  DECL will be the called function, or NULL if
1427   this is an indirect call.  */
1428DEFHOOK
1429(function_ok_for_sibcall,
1430 "",
1431 bool, (tree decl, tree exp),
1432 hook_bool_tree_tree_false)
1433
1434/* Establish appropriate back-end context for processing the function
1435   FNDECL.  The argument might be NULL to indicate processing at top
1436   level, outside of any function scope.  */
1437DEFHOOK
1438(set_current_function,
1439 "",
1440 void, (tree decl), hook_void_tree)
1441
1442/* True if EXP should be placed in a "small data" section.  */
1443DEFHOOK
1444(in_small_data_p,
1445 "",
1446 bool, (const_tree exp),
1447 hook_bool_const_tree_false)
1448
1449/* True if EXP names an object for which name resolution must resolve
1450   to the current executable or shared library.  */
1451DEFHOOK
1452(binds_local_p,
1453 "",
1454 bool, (const_tree exp),
1455 default_binds_local_p)
1456
1457/* Check if profiling code is before or after prologue.  */
1458DEFHOOK
1459(profile_before_prologue,
1460 "It returns true if target wants profile code emitted before prologue.\n\n\
1461The default version of this hook use the target macro\n\
1462@code{PROFILE_BEFORE_PROLOGUE}.",
1463 bool, (void),
1464 default_profile_before_prologue)
1465
1466/* Modify and return the identifier of a DECL's external name,
1467   originally identified by ID, as required by the target,
1468   (eg, append @nn to windows32 stdcall function names).
1469   The default is to return ID without modification. */
1470DEFHOOK
1471(mangle_decl_assembler_name,
1472 "",
1473 tree, (tree decl, tree  id),
1474 default_mangle_decl_assembler_name)
1475
1476/* Do something target-specific to record properties of the DECL into
1477   the associated SYMBOL_REF.  */
1478DEFHOOK
1479(encode_section_info,
1480 "",
1481 void, (tree decl, rtx rtl, int new_decl_p),
1482 default_encode_section_info)
1483
1484/* Undo the effects of encode_section_info on the symbol string.  */
1485DEFHOOK
1486(strip_name_encoding,
1487 "",
1488 const char *, (const char *name),
1489 default_strip_name_encoding)
1490
1491/* If shift optabs for MODE are known to always truncate the shift count,
1492   return the mask that they apply.  Return 0 otherwise.  */
1493DEFHOOK
1494(shift_truncation_mask,
1495 "",
1496 unsigned HOST_WIDE_INT, (enum machine_mode mode),
1497 default_shift_truncation_mask)
1498
1499/* Return the number of divisions in the given MODE that should be present,
1500   so that it is profitable to turn the division into a multiplication by
1501   the reciprocal.  */
1502DEFHOOK
1503(min_divisions_for_recip_mul,
1504 "",
1505 unsigned int, (enum machine_mode mode),
1506 default_min_divisions_for_recip_mul)
1507
1508/* If the representation of integral MODE is such that values are
1509   always sign-extended to a wider mode MODE_REP then return
1510   SIGN_EXTEND.  Return UNKNOWN otherwise.  */
1511/* Note that the return type ought to be RTX_CODE, but that's not
1512   necessarily defined at this point.  */
1513DEFHOOK
1514(mode_rep_extended,
1515 "",
1516 int, (enum machine_mode mode, enum machine_mode rep_mode),
1517 default_mode_rep_extended)
1518
1519/* True if MODE is valid for a pointer in __attribute__((mode("MODE"))).  */
1520DEFHOOK
1521(valid_pointer_mode,
1522 "",
1523 bool, (enum machine_mode mode),
1524 default_valid_pointer_mode)
1525
1526/* Disambiguate with errno.  */
1527DEFHOOK
1528(ref_may_alias_errno,
1529 "Define this to return nonzero if the memory reference @var{ref}\
1530  may alias with the system C library errno location.  The default\
1531  version of this hook assumes the system C library errno location\
1532  is either a declaration of type int or accessed by dereferencing\
1533  a pointer to int.",
1534 bool, (struct ao_ref_s *ref),
1535 default_ref_may_alias_errno)
1536
1537/* Support for named address spaces.  */
1538#undef HOOK_PREFIX
1539#define HOOK_PREFIX "TARGET_ADDR_SPACE_"
1540HOOK_VECTOR (TARGET_ADDR_SPACE_HOOKS, addr_space)
1541
1542/* MODE to use for a pointer into another address space.  */
1543DEFHOOK
1544(pointer_mode,
1545 "",
1546 enum machine_mode, (addr_space_t address_space),
1547 default_addr_space_pointer_mode)
1548
1549/* MODE to use for an address in another address space.  */
1550DEFHOOK
1551(address_mode,
1552 "",
1553 enum machine_mode, (addr_space_t address_space),
1554 default_addr_space_address_mode)
1555
1556/* True if MODE is valid for a pointer in __attribute__((mode("MODE")))
1557   in another address space.  */
1558DEFHOOK
1559(valid_pointer_mode,
1560 "",
1561 bool, (enum machine_mode mode, addr_space_t as),
1562 default_addr_space_valid_pointer_mode)
1563
1564/* True if an address is a valid memory address to a given named address
1565   space for a given mode.  */
1566DEFHOOK
1567(legitimate_address_p,
1568 "",
1569 bool, (enum machine_mode mode, rtx exp, bool strict, addr_space_t as),
1570 default_addr_space_legitimate_address_p)
1571
1572/* Return an updated address to convert an invalid pointer to a named
1573   address space to a valid one.  If NULL_RTX is returned use machine
1574   independent methods to make the address valid.  */
1575DEFHOOK
1576(legitimize_address,
1577 "",
1578 rtx, (rtx x, rtx oldx, enum machine_mode mode, addr_space_t as),
1579 default_addr_space_legitimize_address)
1580
1581/* True if one named address space is a subset of another named address. */
1582DEFHOOK
1583(subset_p,
1584 "",
1585 bool, (addr_space_t subset, addr_space_t superset),
1586 default_addr_space_subset_p)
1587
1588/* Function to convert an rtl expression from one address space to another.  */
1589DEFHOOK
1590(convert,
1591 "",
1592 rtx, (rtx op, tree from_type, tree to_type),
1593 default_addr_space_convert)
1594
1595HOOK_VECTOR_END (addr_space)
1596
1597#undef HOOK_PREFIX
1598#define HOOK_PREFIX "TARGET_"
1599
1600/* True if MODE is valid for the target.  By "valid", we mean able to
1601   be manipulated in non-trivial ways.  In particular, this means all
1602   the arithmetic is supported.  */
1603DEFHOOK
1604(scalar_mode_supported_p,
1605 "",
1606 bool, (enum machine_mode mode),
1607 default_scalar_mode_supported_p)
1608
1609/* Similarly for vector modes.  "Supported" here is less strict.  At
1610   least some operations are supported; need to check optabs or builtins
1611   for further details.  */
1612DEFHOOK
1613(vector_mode_supported_p,
1614 "",
1615 bool, (enum machine_mode mode),
1616 hook_bool_mode_false)
1617
1618DEFHOOK
1619(vector_alignment,
1620 "This hook can be used to define the alignment for a vector of type\n\
1621@var{type}, in order to comply with a platform ABI.  The default is to\n\
1622require natural alignment for vector types.  The alignment returned by\n\
1623this hook must be a power-of-two multiple of the default alignment of\n\
1624the vector element type.",
1625 HOST_WIDE_INT, (const_tree type),
1626 default_vector_alignment)
1627
1628/* True if we should try to use a scalar mode to represent an array,
1629   overriding the usual MAX_FIXED_MODE limit.  */
1630DEFHOOK
1631(array_mode_supported_p,
1632 "Return true if GCC should try to use a scalar mode to store an array\n\
1633of @var{nelems} elements, given that each element has mode @var{mode}.\n\
1634Returning true here overrides the usual @code{MAX_FIXED_MODE} limit\n\
1635and allows GCC to use any defined integer mode.\n\
1636\n\
1637One use of this hook is to support vector load and store operations\n\
1638that operate on several homogeneous vectors.  For example, ARM NEON\n\
1639has operations like:\n\
1640\n\
1641@smallexample\n\
1642int8x8x3_t vld3_s8 (const int8_t *)\n\
1643@end smallexample\n\
1644\n\
1645where the return type is defined as:\n\
1646\n\
1647@smallexample\n\
1648typedef struct int8x8x3_t\n\
1649@{\n\
1650  int8x8_t val[3];\n\
1651@} int8x8x3_t;\n\
1652@end smallexample\n\
1653\n\
1654If this hook allows @code{val} to have a scalar mode, then\n\
1655@code{int8x8x3_t} can have the same mode.  GCC can then store\n\
1656@code{int8x8x3_t}s in registers rather than forcing them onto the stack.",
1657 bool, (enum machine_mode mode, unsigned HOST_WIDE_INT nelems),
1658 hook_bool_mode_uhwi_false)
1659
1660/* Compute cost of moving data from a register of class FROM to one of
1661   TO, using MODE.  */
1662DEFHOOK
1663(register_move_cost,
1664 "",
1665 int, (enum machine_mode mode, reg_class_t from, reg_class_t to),
1666 default_register_move_cost)
1667
1668/* Compute cost of moving registers to/from memory.  */
1669/* ??? Documenting the argument types for this hook requires a GFDL
1670   license grant.  Also, the documentation uses a different name for RCLASS.  */
1671DEFHOOK
1672(memory_move_cost,
1673 "",
1674 int, (enum machine_mode mode, reg_class_t rclass, bool in),
1675 default_memory_move_cost)
1676
1677/* True for MODE if the target expects that registers in this mode will
1678   be allocated to registers in a small register class.  The compiler is
1679   allowed to use registers explicitly used in the rtl as spill registers
1680   but it should prevent extending the lifetime of these registers.  */
1681DEFHOOK
1682(small_register_classes_for_mode_p,
1683 "",
1684 bool, (enum machine_mode mode),
1685 hook_bool_mode_false)
1686
1687/* Register number for a flags register.  Only needs to be defined if the
1688   target is constrainted to use post-reload comparison elimination.  */
1689DEFHOOKPOD
1690(flags_regnum,
1691 "If the target has a dedicated flags register, and it needs to use the\
1692 post-reload comparison elimination pass, then this value should be set\
1693 appropriately.",
1694 unsigned int, INVALID_REGNUM)
1695
1696/* Compute a (partial) cost for rtx X.  Return true if the complete
1697   cost has been computed, and false if subexpressions should be
1698   scanned.  In either case, *TOTAL contains the cost result.  */
1699/* Note that CODE and OUTER_CODE ought to be RTX_CODE, but that's
1700   not necessarily defined at this point.  */
1701DEFHOOK
1702(rtx_costs,
1703 "",
1704 bool, (rtx x, int code, int outer_code, int opno, int *total, bool speed),
1705 hook_bool_rtx_int_int_int_intp_bool_false)
1706
1707/* Compute the cost of X, used as an address.  Never called with
1708   invalid addresses.  */
1709DEFHOOK
1710(address_cost,
1711 "",
1712 int, (rtx address, bool speed),
1713 default_address_cost)
1714
1715/* Return where to allocate pseudo for a given hard register initial value.  */
1716DEFHOOK
1717(allocate_initial_value,
1718 "",
1719 rtx, (rtx hard_reg), NULL)
1720
1721/* Return nonzero if evaluating UNSPEC[_VOLATILE] X might cause a trap.
1722   FLAGS has the same meaning as in rtlanal.c: may_trap_p_1.  */
1723DEFHOOK
1724(unspec_may_trap_p,
1725 "",
1726 int, (const_rtx x, unsigned flags),
1727 default_unspec_may_trap_p)
1728
1729/* Given a register, this hook should return a parallel of registers
1730   to represent where to find the register pieces.  Define this hook
1731   if the register and its mode are represented in Dwarf in
1732   non-contiguous locations, or if the register should be
1733   represented in more than one register in Dwarf.  Otherwise, this
1734   hook should return NULL_RTX.  */
1735DEFHOOK
1736(dwarf_register_span,
1737 "",
1738 rtx, (rtx reg),
1739 hook_rtx_rtx_null)
1740
1741/* If expand_builtin_init_dwarf_reg_sizes needs to fill in table
1742   entries not corresponding directly to registers below
1743   FIRST_PSEUDO_REGISTER, this hook should generate the necessary
1744   code, given the address of the table.  */
1745DEFHOOK
1746(init_dwarf_reg_sizes_extra,
1747 "",
1748 void, (tree address),
1749 hook_void_tree)
1750
1751/* Fetch the fixed register(s) which hold condition codes, for
1752   targets where it makes sense to look for duplicate assignments to
1753   the condition codes.  This should return true if there is such a
1754   register, false otherwise.  The arguments should be set to the
1755   fixed register numbers.  Up to two condition code registers are
1756   supported.  If there is only one for this target, the int pointed
1757   at by the second argument should be set to -1.  */
1758DEFHOOK
1759(fixed_condition_code_regs,
1760 "",
1761 bool, (unsigned int *p1, unsigned int *p2),
1762 hook_bool_uintp_uintp_false)
1763
1764/* If two condition code modes are compatible, return a condition
1765     code mode which is compatible with both, such that a comparison
1766     done in the returned mode will work for both of the original
1767     modes.  If the condition code modes are not compatible, return
1768     VOIDmode.  */
1769DEFHOOK
1770(cc_modes_compatible,
1771 "",
1772 enum machine_mode, (enum machine_mode m1, enum machine_mode m2),
1773 default_cc_modes_compatible)
1774
1775/* Do machine-dependent code transformations.  Called just before
1776     delayed-branch scheduling.  */
1777DEFHOOK
1778(machine_dependent_reorg,
1779 "",
1780 void, (void), NULL)
1781
1782/* Create the __builtin_va_list type.  */
1783DEFHOOK
1784(build_builtin_va_list,
1785 "",
1786 tree, (void),
1787 std_build_builtin_va_list)
1788
1789/* Enumerate the va list variants.  */
1790DEFHOOK
1791(enum_va_list_p,
1792 "",
1793 int, (int idx, const char **pname, tree *ptree),
1794 NULL)
1795
1796/* Get the cfun/fndecl calling abi __builtin_va_list type.  */
1797DEFHOOK
1798(fn_abi_va_list,
1799 "",
1800 tree, (tree fndecl),
1801 std_fn_abi_va_list)
1802
1803/* Get the __builtin_va_list type dependent on input type.  */
1804DEFHOOK
1805(canonical_va_list_type,
1806 "",
1807 tree, (tree type),
1808 std_canonical_va_list_type)
1809
1810/* ??? Documenting this hook requires a GFDL license grant.  */
1811DEFHOOK_UNDOC
1812(expand_builtin_va_start,
1813"Expand the @code{__builtin_va_start} builtin.",
1814 void, (tree valist, rtx nextarg), NULL)
1815
1816/* Gimplifies a VA_ARG_EXPR.  */
1817DEFHOOK
1818(gimplify_va_arg_expr,
1819 "",
1820 tree, (tree valist, tree type, gimple_seq *pre_p, gimple_seq *post_p),
1821 std_gimplify_va_arg_expr)
1822
1823/* Validity-checking routines for PCH files, target-specific.
1824   get_pch_validity returns a pointer to the data to be stored,
1825   and stores the size in its argument.  pch_valid_p gets the same
1826   information back and returns NULL if the PCH is valid,
1827   or an error message if not.  */
1828DEFHOOK
1829(get_pch_validity,
1830 "",
1831 void *, (size_t *sz),
1832 default_get_pch_validity)
1833
1834DEFHOOK
1835(pch_valid_p,
1836 "",
1837 const char *, (const void *data, size_t sz),
1838 default_pch_valid_p)
1839
1840DEFHOOK
1841(prepare_pch_save,
1842 "Called before writing out a PCH file.  If the target has some\n\
1843garbage-collected data that needs to be in a particular state on PCH loads,\n\
1844it can use this hook to enforce that state.  Very few targets need\n\
1845to do anything here.",
1846 void, (void),
1847 hook_void_void)
1848
1849/* If nonnull, this function checks whether a PCH file with the
1850   given set of target flags can be used.  It returns NULL if so,
1851   otherwise it returns an error message.  */
1852DEFHOOK
1853(check_pch_target_flags,
1854 "",
1855 const char *, (int pch_flags), NULL)
1856
1857/* True if the compiler should give an enum type only as many
1858   bytes as it takes to represent the range of possible values of
1859   that type.  */
1860DEFHOOK
1861(default_short_enums,
1862 "",
1863 bool, (void),
1864 hook_bool_void_false)
1865
1866/* This target hook returns an rtx that is used to store the address
1867   of the current frame into the built-in setjmp buffer.  */
1868DEFHOOK
1869(builtin_setjmp_frame_value,
1870 "",
1871 rtx, (void),
1872 default_builtin_setjmp_frame_value)
1873
1874/* This target hook should add STRING_CST trees for any hard regs
1875   the port wishes to automatically clobber for an asm.  */
1876DEFHOOK
1877(md_asm_clobbers,
1878 "",
1879 tree, (tree outputs, tree inputs, tree clobbers),
1880 hook_tree_tree_tree_tree_3rd_identity)
1881
1882/* This target hook allows the backend to specify a calling convention
1883   in the debug information.  This function actually returns an
1884   enum dwarf_calling_convention, but because of forward declarations
1885   and not wanting to include dwarf2.h everywhere target.h is included
1886   the function is being declared as an int.  */
1887DEFHOOK
1888(dwarf_calling_convention,
1889 "",
1890 int, (const_tree function),
1891 hook_int_const_tree_0)
1892
1893/* This target hook allows the backend to emit frame-related insns that
1894   contain UNSPECs or UNSPEC_VOLATILEs.  The call frame debugging info
1895   engine will invoke it on insns of the form
1896     (set (reg) (unspec [...] UNSPEC_INDEX))
1897   and
1898     (set (reg) (unspec_volatile [...] UNSPECV_INDEX))
1899   to let the backend emit the call frame instructions.  */
1900DEFHOOK
1901(dwarf_handle_frame_unspec,
1902 "",
1903 void, (const char *label, rtx pattern, int index), NULL)
1904
1905/* ??? Documenting this hook requires a GFDL license grant.  */
1906DEFHOOK_UNDOC
1907(stdarg_optimize_hook,
1908"Perform architecture specific checking of statements gimplified\
1909 from @code{VA_ARG_EXPR}.  @var{stmt} is the statement.  Returns true if\
1910 the statement doesn't need to be checked for @code{va_list} references.",
1911 bool, (struct stdarg_info *ai, const_gimple stmt), NULL)
1912
1913/* This target hook allows the operating system to override the DECL
1914   that represents the external variable that contains the stack
1915   protection guard variable.  The type of this DECL is ptr_type_node.  */
1916DEFHOOK
1917(stack_protect_guard,
1918 "",
1919 tree, (void),
1920 default_stack_protect_guard)
1921
1922/* This target hook allows the operating system to override the CALL_EXPR
1923   that is invoked when a check vs the guard variable fails.  */
1924DEFHOOK
1925(stack_protect_fail,
1926 "",
1927 tree, (void),
1928 default_external_stack_protect_fail)
1929
1930/* Returns NULL if target supports the insn within a doloop block,
1931   otherwise it returns an error message.  */
1932DEFHOOK
1933(invalid_within_doloop,
1934 "",
1935 const char *, (const_rtx insn),
1936 default_invalid_within_doloop)
1937
1938DEFHOOK
1939(valid_dllimport_attribute_p,
1940"@var{decl} is a variable or function with @code{__attribute__((dllimport))}\
1941 specified.  Use this hook if the target needs to add extra validation\
1942 checks to @code{handle_dll_attribute}.",
1943 bool, (const_tree decl),
1944 hook_bool_const_tree_true)
1945
1946/* If non-zero, align constant anchors in CSE to a multiple of this
1947   value.  */
1948DEFHOOKPOD
1949(const_anchor,
1950 "",
1951 unsigned HOST_WIDE_INT, 0)
1952
1953/* Functions relating to calls - argument passing, returns, etc.  */
1954/* Members of struct call have no special macro prefix.  */
1955HOOK_VECTOR (TARGET_CALLS, calls)
1956
1957DEFHOOK
1958(promote_function_mode,
1959 "",
1960 enum machine_mode, (const_tree type, enum machine_mode mode, int *punsignedp,
1961		     const_tree funtype, int for_return),
1962 default_promote_function_mode)
1963
1964DEFHOOK
1965(promote_prototypes,
1966 "",
1967 bool, (const_tree fntype),
1968 hook_bool_const_tree_false)
1969
1970DEFHOOK
1971(struct_value_rtx,
1972 "",
1973 rtx, (tree fndecl, int incoming),
1974 hook_rtx_tree_int_null)
1975DEFHOOK
1976(return_in_memory,
1977 "",
1978 bool, (const_tree type, const_tree fntype),
1979 default_return_in_memory)
1980
1981DEFHOOK
1982(return_in_msb,
1983 "",
1984 bool, (const_tree type),
1985 hook_bool_const_tree_false)
1986
1987/* Return true if a parameter must be passed by reference.  TYPE may
1988   be null if this is a libcall.  CA may be null if this query is
1989   from __builtin_va_arg.  */
1990DEFHOOK
1991(pass_by_reference,
1992 "",
1993 bool,
1994 (cumulative_args_t cum, enum machine_mode mode, const_tree type, bool named),
1995 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false)
1996
1997DEFHOOK
1998(expand_builtin_saveregs,
1999 "",
2000 rtx, (void),
2001 default_expand_builtin_saveregs)
2002
2003/* Returns pretend_argument_size.  */
2004DEFHOOK
2005(setup_incoming_varargs,
2006 "",
2007 void, (cumulative_args_t args_so_far, enum machine_mode mode, tree type,
2008	int *pretend_args_size, int second_time),
2009 default_setup_incoming_varargs)
2010
2011DEFHOOK
2012(strict_argument_naming,
2013 "",
2014 bool, (cumulative_args_t ca),
2015 hook_bool_CUMULATIVE_ARGS_false)
2016
2017/* Returns true if we should use
2018   targetm.calls.setup_incoming_varargs() and/or
2019   targetm.calls.strict_argument_naming().  */
2020DEFHOOK
2021(pretend_outgoing_varargs_named,
2022 "",
2023 bool, (cumulative_args_t ca),
2024 default_pretend_outgoing_varargs_named)
2025
2026/* Given a complex type T, return true if a parameter of type T
2027   should be passed as two scalars.  */
2028DEFHOOK
2029(split_complex_arg,
2030 "",
2031 bool, (const_tree type), NULL)
2032
2033/* Return true if type T, mode MODE, may not be passed in registers,
2034   but must be passed on the stack.  */
2035/* ??? This predicate should be applied strictly after pass-by-reference.
2036   Need audit to verify that this is the case.  */
2037DEFHOOK
2038(must_pass_in_stack,
2039 "",
2040 bool, (enum machine_mode mode, const_tree type),
2041 must_pass_in_stack_var_size_or_pad)
2042
2043/* Return true if type TYPE, mode MODE, which is passed by reference,
2044   should have the object copy generated by the callee rather than
2045   the caller.  It is never called for TYPE requiring constructors.  */
2046DEFHOOK
2047(callee_copies,
2048 "",
2049 bool,
2050 (cumulative_args_t cum, enum machine_mode mode, const_tree type, bool named),
2051 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false)
2052
2053/* Return zero for arguments passed entirely on the stack or entirely
2054   in registers.  If passed in both, return the number of bytes passed
2055   in registers; the balance is therefore passed on the stack.  */
2056DEFHOOK
2057(arg_partial_bytes,
2058 "",
2059 int, (cumulative_args_t cum, enum machine_mode mode, tree type, bool named),
2060 hook_int_CUMULATIVE_ARGS_mode_tree_bool_0)
2061
2062/* Update the state in CA to advance past an argument in the
2063   argument list.  The values MODE, TYPE, and NAMED describe that
2064   argument.  */
2065DEFHOOK
2066(function_arg_advance,
2067 "",
2068 void,
2069 (cumulative_args_t ca, enum machine_mode mode, const_tree type, bool named),
2070 default_function_arg_advance)
2071
2072/* Return zero if the argument described by the state of CA should
2073   be placed on a stack, or a hard register in which to store the
2074   argument.  The values MODE, TYPE, and NAMED describe that
2075   argument.  */
2076DEFHOOK
2077(function_arg,
2078 "",
2079 rtx, (cumulative_args_t ca, enum machine_mode mode, const_tree type,
2080       bool named),
2081 default_function_arg)
2082
2083/* Likewise, but for machines with register windows.  Return the
2084   location where the argument will appear to the callee.  */
2085DEFHOOK
2086(function_incoming_arg,
2087 "",
2088 rtx, (cumulative_args_t ca, enum machine_mode mode, const_tree type,
2089       bool named),
2090 default_function_incoming_arg)
2091
2092DEFHOOK
2093(function_arg_boundary,
2094 "",
2095 unsigned int, (enum machine_mode mode, const_tree type),
2096 default_function_arg_boundary)
2097
2098DEFHOOK
2099(function_arg_round_boundary,
2100 "Normally, the size of an argument is rounded up to @code{PARM_BOUNDARY},\n\
2101which is the default value for this hook.  You can define this hook to\n\
2102return a different value if an argument size must be rounded to a larger\n\
2103value.",
2104 unsigned int, (enum machine_mode mode, const_tree type),
2105 default_function_arg_round_boundary)
2106
2107/* Return the diagnostic message string if function without a prototype
2108   is not allowed for this 'val' argument; NULL otherwise. */
2109DEFHOOK
2110(invalid_arg_for_unprototyped_fn,
2111 "",
2112 const char *, (const_tree typelist, const_tree funcdecl, const_tree val),
2113 hook_invalid_arg_for_unprototyped_fn)
2114
2115/* Return an rtx for the return value location of the function
2116   specified by FN_DECL_OR_TYPE with a return type of RET_TYPE.  */
2117DEFHOOK
2118(function_value,
2119 "",
2120 rtx, (const_tree ret_type, const_tree fn_decl_or_type, bool outgoing),
2121 default_function_value)
2122
2123/* Return the rtx for the result of a libcall of mode MODE,
2124   calling the function FN_NAME.  */
2125DEFHOOK
2126(libcall_value,
2127 "",
2128 rtx, (enum machine_mode mode, const_rtx fun),
2129 default_libcall_value)
2130
2131/* Return true if REGNO is a possible register number for
2132   a function value as seen by the caller.  */
2133DEFHOOK
2134(function_value_regno_p,
2135 "",
2136 bool, (const unsigned int regno),
2137 default_function_value_regno_p)
2138
2139/* ??? Documenting this hook requires a GFDL license grant.  */
2140DEFHOOK_UNDOC
2141(internal_arg_pointer,
2142"Return an rtx for the argument pointer incoming to the\
2143 current function.",
2144 rtx, (void),
2145 default_internal_arg_pointer)
2146
2147/* Update the current function stack boundary if needed.  */
2148DEFHOOK
2149(update_stack_boundary,
2150 "",
2151 void, (void), NULL)
2152
2153/* Handle stack alignment and return an rtx for Dynamic Realign
2154   Argument Pointer if necessary.  */
2155DEFHOOK
2156(get_drap_rtx,
2157 "",
2158 rtx, (void), NULL)
2159
2160/* Return true if all function parameters should be spilled to the
2161   stack.  */
2162DEFHOOK
2163(allocate_stack_slots_for_args,
2164 "",
2165 bool, (void),
2166 hook_bool_void_true)
2167
2168/* Return an rtx for the static chain for FNDECL.  If INCOMING_P is true,
2169       then it should be for the callee; otherwise for the caller.  */
2170DEFHOOK
2171(static_chain,
2172 "",
2173 rtx, (const_tree fndecl, bool incoming_p),
2174 default_static_chain)
2175
2176/* Fill in the trampoline at MEM with a call to FNDECL and a
2177   static chain value of CHAIN.  */
2178DEFHOOK
2179(trampoline_init,
2180 "",
2181 void, (rtx m_tramp, tree fndecl, rtx static_chain),
2182 default_trampoline_init)
2183
2184/* Adjust the address of the trampoline in a target-specific way.  */
2185DEFHOOK
2186(trampoline_adjust_address,
2187 "",
2188 rtx, (rtx addr), NULL)
2189
2190/* Return the number of bytes of its own arguments that a function
2191   pops on returning, or 0 if the function pops no arguments and the
2192   caller must therefore pop them all after the function returns.  */
2193/* ??? tm.texi has no types for the parameters.  */
2194DEFHOOK
2195(return_pops_args,
2196 "",
2197 int, (tree fundecl, tree funtype, int size),
2198 default_return_pops_args)
2199
2200/* Return a mode wide enough to copy any function value that might be
2201   returned.  */
2202DEFHOOK
2203(get_raw_result_mode,
2204 "This target hook returns the mode to be used when accessing raw return\
2205 registers in @code{__builtin_return}.  Define this macro if the value\
2206 in @var{reg_raw_mode} is not correct.",
2207 enum machine_mode, (int regno),
2208 default_get_reg_raw_mode)
2209
2210/* Return a mode wide enough to copy any argument value that might be
2211   passed.  */
2212DEFHOOK
2213(get_raw_arg_mode,
2214 "This target hook returns the mode to be used when accessing raw argument\
2215 registers in @code{__builtin_apply_args}.  Define this macro if the value\
2216 in @var{reg_raw_mode} is not correct.",
2217 enum machine_mode, (int regno),
2218 default_get_reg_raw_mode)
2219
2220HOOK_VECTOR_END (calls)
2221
2222/* Return the diagnostic message string if conversion from FROMTYPE
2223   to TOTYPE is not allowed, NULL otherwise.  */
2224DEFHOOK
2225(invalid_conversion,
2226 "",
2227 const char *, (const_tree fromtype, const_tree totype),
2228 hook_constcharptr_const_tree_const_tree_null)
2229
2230/* Return the diagnostic message string if the unary operation OP is
2231   not permitted on TYPE, NULL otherwise.  */
2232DEFHOOK
2233(invalid_unary_op,
2234 "",
2235 const char *, (int op, const_tree type),
2236 hook_constcharptr_int_const_tree_null)
2237
2238/* Return the diagnostic message string if the binary operation OP
2239   is not permitted on TYPE1 and TYPE2, NULL otherwise.  */
2240DEFHOOK
2241(invalid_binary_op,
2242 "",
2243 const char *, (int op, const_tree type1, const_tree type2),
2244 hook_constcharptr_int_const_tree_const_tree_null)
2245
2246/* Return the diagnostic message string if TYPE is not valid as a
2247   function parameter type, NULL otherwise.  */
2248DEFHOOK
2249(invalid_parameter_type,
2250 "",
2251 const char *, (const_tree type),
2252 hook_constcharptr_const_tree_null)
2253
2254/* Return the diagnostic message string if TYPE is not valid as a
2255   function return type, NULL otherwise.  */
2256DEFHOOK
2257(invalid_return_type,
2258 "",
2259 const char *, (const_tree type),
2260 hook_constcharptr_const_tree_null)
2261
2262/* If values of TYPE are promoted to some other type when used in
2263   expressions (analogous to the integer promotions), return that type,
2264   or NULL_TREE otherwise.  */
2265DEFHOOK
2266(promoted_type,
2267 "",
2268 tree, (const_tree type),
2269 hook_tree_const_tree_null)
2270
2271/* Convert EXPR to TYPE, if target-specific types with special conversion
2272   rules are involved.  Return the converted expression, or NULL to apply
2273   the standard conversion rules.  */
2274DEFHOOK
2275(convert_to_type,
2276 "",
2277 tree, (tree type, tree expr),
2278 hook_tree_tree_tree_null)
2279
2280/* Return the class for a secondary reload, and fill in extra information.  */
2281DEFHOOK
2282(secondary_reload,
2283 "",
2284 reg_class_t,
2285 (bool in_p, rtx x, reg_class_t reload_class, enum machine_mode reload_mode,
2286  secondary_reload_info *sri),
2287 default_secondary_reload)
2288
2289/* Given an rtx X being reloaded into a reg required to be in class CLASS,
2290   return the class of reg to actually use.  */
2291DEFHOOK
2292(preferred_reload_class,
2293 "",
2294 reg_class_t,
2295 (rtx x, reg_class_t rclass),
2296 default_preferred_reload_class)
2297
2298/* Like TARGET_PREFERRED_RELOAD_CLASS, but for output reloads instead of
2299   input reloads.  */
2300DEFHOOK
2301(preferred_output_reload_class,
2302 "",
2303 reg_class_t,
2304 (rtx x, reg_class_t rclass),
2305 default_preferred_output_reload_class)
2306
2307DEFHOOK
2308(class_likely_spilled_p,
2309 "",
2310 bool, (reg_class_t rclass),
2311 default_class_likely_spilled_p)
2312
2313/* Return the maximum number of consecutive registers
2314   needed to represent mode MODE in a register of class RCLASS.  */
2315DEFHOOK
2316(class_max_nregs,
2317 "",
2318 unsigned char, (reg_class_t rclass, enum machine_mode mode),
2319 default_class_max_nregs)
2320
2321DEFHOOK
2322(preferred_rename_class,
2323 "A target hook that places additional preference on the register\
2324 class to use when it is necessary to rename a register in class\
2325 @var{rclass} to another class, or perhaps @var{NO_REGS}, if no\
2326 preferred register class is found or hook @code{preferred_rename_class}\
2327 is not implemented.\
2328 Sometimes returning a more restrictive class makes better code.  For\
2329 example, on ARM, thumb-2 instructions using @code{LO_REGS} may be\
2330 smaller than instructions using @code{GENERIC_REGS}.  By returning\
2331 @code{LO_REGS} from @code{preferred_rename_class}, code size can\
2332 be reduced.",
2333 reg_class_t, (reg_class_t rclass),
2334 default_preferred_rename_class)
2335
2336/* This target hook allows the backend to perform additional
2337   processing while initializing for variable expansion.  */
2338DEFHOOK
2339(expand_to_rtl_hook,
2340 "",
2341 void, (void),
2342 hook_void_void)
2343
2344/* This target hook allows the backend to perform additional
2345   instantiations on rtx that are not actually in insns yet,
2346   but will be later.  */
2347DEFHOOK
2348(instantiate_decls,
2349 "",
2350 void, (void),
2351 hook_void_void)
2352
2353/* Return true if is OK to use a hard register REGNO as scratch register
2354   in peephole2.  */
2355DEFHOOK
2356(hard_regno_scratch_ok,
2357 "",
2358 bool, (unsigned int regno),
2359 default_hard_regno_scratch_ok)
2360
2361/* Return the smallest number of different values for which it is best to
2362   use a jump-table instead of a tree of conditional branches.  */
2363DEFHOOK
2364(case_values_threshold,
2365 "",
2366 unsigned int, (void),
2367 default_case_values_threshold)
2368
2369/* Retutn true if a function must have and use a frame pointer.  */
2370DEFHOOK
2371(frame_pointer_required,
2372 "",
2373 bool, (void),
2374 hook_bool_void_false)
2375
2376/* Returns true if the compiler is allowed to try to replace register number
2377   from-reg with register number to-reg.  */
2378DEFHOOK
2379(can_eliminate,
2380 "",
2381 bool, (const int from_reg, const int to_reg),
2382 hook_bool_const_int_const_int_true)
2383
2384/* Modify any or all of fixed_regs, call_used_regs, global_regs,
2385   reg_names, and reg_class_contents to account of the vagaries of the
2386   target.  */
2387DEFHOOK
2388(conditional_register_usage,
2389 "",
2390 void, (void),
2391 hook_void_void)
2392
2393/* Functions specific to the C family of frontends.  */
2394#undef HOOK_PREFIX
2395#define HOOK_PREFIX "TARGET_C_"
2396HOOK_VECTOR (TARGET_C, c)
2397
2398/* ??? Documenting this hook requires a GFDL license grant.  */
2399DEFHOOK_UNDOC
2400(mode_for_suffix,
2401"Return machine mode for non-standard constant literal suffix @var{c},\
2402 or VOIDmode if non-standard suffixes are unsupported.",
2403 enum machine_mode, (char c),
2404 default_mode_for_suffix)
2405
2406HOOK_VECTOR_END (c)
2407
2408/* Functions specific to the C++ frontend.  */
2409#undef HOOK_PREFIX
2410#define HOOK_PREFIX "TARGET_CXX_"
2411HOOK_VECTOR (TARGET_CXX, cxx)
2412
2413/* Return the integer type used for guard variables.  */
2414DEFHOOK
2415(guard_type,
2416 "",
2417 tree, (void),
2418 default_cxx_guard_type)
2419
2420/* Return true if only the low bit of the guard should be tested.  */
2421DEFHOOK
2422(guard_mask_bit,
2423 "",
2424 bool, (void),
2425 hook_bool_void_false)
2426
2427/* Returns the size of the array cookie for an array of type.  */
2428DEFHOOK
2429(get_cookie_size,
2430 "",
2431 tree, (tree type),
2432 default_cxx_get_cookie_size)
2433
2434/* Returns true if the element size should be stored in the array cookie.  */
2435DEFHOOK
2436(cookie_has_size,
2437 "",
2438 bool, (void),
2439 hook_bool_void_false)
2440
2441/* Allows backends to perform additional processing when
2442   deciding if a class should be exported or imported.  */
2443DEFHOOK
2444(import_export_class,
2445 "",
2446 int, (tree type, int import_export), NULL)
2447
2448/* Returns true if constructors and destructors return "this".  */
2449DEFHOOK
2450(cdtor_returns_this,
2451 "",
2452 bool, (void),
2453 hook_bool_void_false)
2454
2455/* Returns true if the key method for a class can be an inline
2456   function, so long as it is not declared inline in the class
2457   itself.  Returning true is the behavior required by the Itanium C++ ABI.  */
2458DEFHOOK
2459(key_method_may_be_inline,
2460 "",
2461 bool, (void),
2462 hook_bool_void_true)
2463
2464DEFHOOK
2465(determine_class_data_visibility,
2466"@var{decl} is a virtual table, virtual table table, typeinfo object,\
2467 or other similar implicit class data object that will be emitted with\
2468 external linkage in this translation unit.  No ELF visibility has been\
2469 explicitly specified.  If the target needs to specify a visibility\
2470 other than that of the containing class, use this hook to set\
2471 @code{DECL_VISIBILITY} and @code{DECL_VISIBILITY_SPECIFIED}.",
2472 void, (tree decl),
2473 hook_void_tree)
2474
2475/* Returns true (the default) if virtual tables and other
2476   similar implicit class data objects are always COMDAT if they
2477   have external linkage.  If this hook returns false, then
2478   class data for classes whose virtual table will be emitted in
2479   only one translation unit will not be COMDAT.  */
2480DEFHOOK
2481(class_data_always_comdat,
2482 "",
2483 bool, (void),
2484 hook_bool_void_true)
2485
2486/* Returns true (the default) if the RTTI for the basic types,
2487   which is always defined in the C++ runtime, should be COMDAT;
2488   false if it should not be COMDAT.  */
2489DEFHOOK
2490(library_rtti_comdat,
2491 "",
2492 bool, (void),
2493 hook_bool_void_true)
2494
2495/* Returns true if __aeabi_atexit should be used to register static
2496   destructors.  */
2497DEFHOOK
2498(use_aeabi_atexit,
2499 "",
2500 bool, (void),
2501 hook_bool_void_false)
2502
2503/* Returns true if target may use atexit in the same manner as
2504   __cxa_atexit  to register static destructors.  */
2505DEFHOOK
2506(use_atexit_for_cxa_atexit,
2507 "",
2508 bool, (void),
2509 hook_bool_void_false)
2510
2511DEFHOOK
2512(adjust_class_at_definition,
2513"@var{type} is a C++ class (i.e., RECORD_TYPE or UNION_TYPE) that has just\
2514 been defined.  Use this hook to make adjustments to the class (eg, tweak\
2515 visibility or perform any other required target modifications).",
2516 void, (tree type),
2517 hook_void_tree)
2518
2519DEFHOOK
2520(decl_mangling_context,
2521 "Return target-specific mangling context of @var{decl} or @code{NULL_TREE}.",
2522 tree, (const_tree decl),
2523 hook_tree_const_tree_null)
2524
2525HOOK_VECTOR_END (cxx)
2526
2527/* Functions and data for emulated TLS support.  */
2528#undef HOOK_PREFIX
2529#define HOOK_PREFIX "TARGET_EMUTLS_"
2530HOOK_VECTOR (TARGET_EMUTLS, emutls)
2531
2532/* Name of the address and common functions.  */
2533DEFHOOKPOD
2534(get_address,
2535 "",
2536 const char *, "__builtin___emutls_get_address")
2537
2538DEFHOOKPOD
2539(register_common,
2540 "",
2541 const char *, "__builtin___emutls_register_common")
2542
2543/* Prefixes for proxy variable and template.  */
2544DEFHOOKPOD
2545(var_section,
2546 "",
2547 const char *, NULL)
2548
2549DEFHOOKPOD
2550(tmpl_section,
2551 "",
2552 const char *, NULL)
2553
2554/* Prefixes for proxy variable and template.  */
2555DEFHOOKPOD
2556(var_prefix,
2557 "",
2558 const char *, NULL)
2559
2560DEFHOOKPOD
2561(tmpl_prefix,
2562 "",
2563 const char *, NULL)
2564
2565/* Function to generate field definitions of the proxy variable.  */
2566DEFHOOK
2567(var_fields,
2568 "",
2569 tree, (tree type, tree *name),
2570 default_emutls_var_fields)
2571
2572/* Function to initialize a proxy variable.  */
2573DEFHOOK
2574(var_init,
2575 "",
2576 tree, (tree var, tree decl, tree tmpl_addr),
2577 default_emutls_var_init)
2578
2579/* Whether we are allowed to alter the usual alignment of the
2580   proxy variable.  */
2581DEFHOOKPOD
2582(var_align_fixed,
2583 "",
2584 bool, false)
2585
2586/* Whether we can emit debug information for TLS vars.  */
2587DEFHOOKPOD
2588(debug_form_tls_address,
2589 "",
2590 bool, false)
2591
2592HOOK_VECTOR_END (emutls)
2593
2594#undef HOOK_PREFIX
2595#define HOOK_PREFIX "TARGET_OPTION_"
2596HOOK_VECTOR (TARGET_OPTION_HOOKS, target_option_hooks)
2597
2598/* Function to validate the attribute((option(...))) strings or NULL.  If
2599   the option is validated, it is assumed that DECL_FUNCTION_SPECIFIC will
2600   be filled in in the function decl node.  */
2601DEFHOOK
2602(valid_attribute_p,
2603 "",
2604 bool, (tree fndecl, tree name, tree args, int flags),
2605 default_target_option_valid_attribute_p)
2606
2607/* Function to save any extra target state in the target options structure.  */
2608DEFHOOK
2609(save,
2610 "",
2611 void, (struct cl_target_option *ptr), NULL)
2612
2613/* Function to restore any extra target state from the target options
2614   structure.  */
2615DEFHOOK
2616(restore,
2617 "",
2618 void, (struct cl_target_option *ptr), NULL)
2619
2620/* Function to print any extra target state from the target options
2621   structure.  */
2622DEFHOOK
2623(print,
2624 "",
2625 void, (FILE *file, int indent, struct cl_target_option *ptr), NULL)
2626
2627/* Function to parse arguments to be validated for #pragma option, and to
2628   change the state if the options are valid.  If the first argument is
2629   NULL, the second argument specifies the default options to use.  Return
2630   true if the options are valid, and set the current state.  */
2631/* ??? The documentation in tm.texi is incomplete.  */
2632DEFHOOK
2633(pragma_parse,
2634 "",
2635 bool, (tree args, tree pop_target),
2636 default_target_option_pragma_parse)
2637
2638/* Do option overrides for the target.  */
2639DEFHOOK
2640(override,
2641 "",
2642 void, (void),
2643 hook_void_void)
2644
2645/* Function to determine if one function can inline another function.  */
2646#undef HOOK_PREFIX
2647#define HOOK_PREFIX "TARGET_"
2648DEFHOOK
2649(can_inline_p,
2650 "",
2651 bool, (tree caller, tree callee),
2652 default_target_can_inline_p)
2653
2654HOOK_VECTOR_END (target_option)
2655
2656/* For targets that need to mark extra registers as live on entry to
2657   the function, they should define this target hook and set their
2658   bits in the bitmap passed in. */
2659DEFHOOK
2660(extra_live_on_entry,
2661 "",
2662 void, (bitmap regs),
2663 hook_void_bitmap)
2664
2665/* Fill in additional registers set up by prologue into a regset.  */
2666DEFHOOK
2667(set_up_by_prologue,
2668 "This hook should add additional registers that are computed by the prologue\
2669 to the hard regset for shrink-wrapping optimization purposes.",
2670 void, (struct hard_reg_set_container *),
2671 NULL)
2672
2673/* Determine the type of unwind info to emit for debugging.  */
2674DEFHOOK
2675(debug_unwind_info,
2676 "",
2677 enum unwind_info_type, (void),
2678 default_debug_unwind_info)
2679
2680DEFHOOKPOD
2681(atomic_test_and_set_trueval,
2682 "This value should be set if the result written by\
2683 @code{atomic_test_and_set} is not exactly 1, i.e. the\
2684 @code{bool} @code{true}.",
2685 unsigned char, 1)
2686
2687/* Leave the boolean fields at the end.  */
2688
2689/* True if we can create zeroed data by switching to a BSS section
2690   and then using ASM_OUTPUT_SKIP to allocate the space.  */
2691DEFHOOKPOD
2692(have_switchable_bss_sections,
2693 "",
2694 bool, false)
2695
2696/* True if "native" constructors and destructors are supported,
2697   false if we're using collect2 for the job.  */
2698DEFHOOKPOD
2699(have_ctors_dtors,
2700 "",
2701 bool, false)
2702
2703/* True if thread-local storage is supported.  */
2704DEFHOOKPOD
2705(have_tls,
2706 "",
2707 bool, false)
2708
2709/* True if a small readonly data section is supported.  */
2710DEFHOOKPOD
2711(have_srodata_section,
2712 "",
2713 bool, false)
2714
2715/* True if EH frame info sections should be zero-terminated.  */
2716DEFHOOKPOD
2717(terminate_dw2_eh_frame_info,
2718 "",
2719 bool, true)
2720
2721/* True if #NO_APP should be emitted at the beginning of assembly output.  */
2722DEFHOOKPOD
2723(asm_file_start_app_off,
2724 "",
2725 bool, false)
2726
2727/* True if output_file_directive should be called for main_input_filename
2728   at the beginning of assembly output.  */
2729DEFHOOKPOD
2730(asm_file_start_file_directive,
2731 "",
2732 bool, false)
2733
2734DEFHOOKPOD
2735(handle_pragma_extern_prefix,
2736"True if @code{#pragma extern_prefix} is to be supported.",
2737 bool, 0)
2738
2739/* True if the target is allowed to reorder memory accesses unless
2740   synchronization is explicitly requested.  */
2741DEFHOOKPOD
2742(relaxed_ordering,
2743 "",
2744 bool, false)
2745
2746/* Returns true if we should generate exception tables for use with the
2747   ARM EABI.  The effects the encoding of function exception specifications.  */
2748DEFHOOKPOD
2749(arm_eabi_unwinder,
2750 "",
2751 bool, false)
2752
2753DEFHOOKPOD
2754(want_debug_pub_sections,
2755 "True if the @code{.debug_pubtypes} and @code{.debug_pubnames} sections\
2756 should be emitted.  These sections are not used on most platforms, and\
2757 in particular GDB does not use them.",
2758 bool, false)
2759
2760DEFHOOKPOD
2761(force_at_comp_dir,
2762 "True if the @code{DW_AT_comp_dir} attribute should be emitted for each \
2763 compilation unit.  This attribute is required for the darwin linker \
2764 to emit debug information.",
2765 bool, false)
2766
2767DEFHOOKPOD
2768(delay_sched2, "True if sched2 is not to be run at its normal place.  \
2769This usually means it will be run as part of machine-specific reorg.",
2770bool, false)
2771
2772DEFHOOKPOD
2773(delay_vartrack, "True if vartrack is not to be run at its normal place.  \
2774This usually means it will be run as part of machine-specific reorg.",
2775bool, false)
2776
2777/* Leave the boolean fields at the end.  */
2778
2779/* Close the 'struct gcc_target' definition.  */
2780HOOK_VECTOR_END (C90_EMPTY_HACK)
2781