In gcc/: 2011-04-14 Nicola Pero <nicola.pero@meta-innovation.com>
[official-gcc.git] / gcc / target.def
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1 /* Target hook definitions.
2 Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
3 2011
4 Free Software Foundation, Inc.
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.
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.
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/>.
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! */
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"
28 #undef HOOK_TYPE
29 #define HOOK_TYPE "Target Hook"
31 HOOK_VECTOR (TARGET_INITIALIZER, gcc_target)
33 /* Functions that output assembler for the target. */
34 #define HOOK_PREFIX "TARGET_ASM_"
35 HOOK_VECTOR (TARGET_ASM_OUT, asm_out)
37 /* Opening and closing parentheses for asm expression grouping. */
38 DEFHOOKPOD
39 (open_paren,
40 "",
41 const char *, "(")
42 DEFHOOKPODX (close_paren, const char *, ")")
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)
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)
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)
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)
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)
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)
97 /* Output code that will globalize a label. */
98 DEFHOOK
99 (globalize_label,
101 void, (FILE *stream, const char *name),
102 default_globalize_label)
104 /* Output code that will globalize a declaration. */
105 DEFHOOK
106 (globalize_decl_name,
108 void, (FILE *stream, tree decl), default_globalize_decl_name)
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,
118 void, (FILE *stream, tree decl, int for_eh, int empty),
119 default_emit_unwind_label)
121 /* Output code that will emit a label to divide up the exception table. */
122 DEFHOOK
123 (emit_except_table_label,
125 void, (FILE *stream),
126 default_emit_except_table_label)
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)
137 /* Emit any directives required to unwind this instruction. */
138 DEFHOOK
139 (unwind_emit,
141 void, (FILE *stream, rtx insn),
142 NULL)
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)
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,
156 void, (char *buf, const char *prefix, unsigned long labelno),
157 default_generate_internal_label)
159 /* Output an internal label. */
160 DEFHOOK
161 (internal_label,
163 void, (FILE *stream, const char *prefix, unsigned long labelno),
164 default_internal_label)
166 /* Output label for the constant. */
167 DEFHOOK
168 (declare_constant_name,
170 void, (FILE *file, const char *name, const_tree expr, HOST_WIDE_INT size),
171 default_asm_declare_constant_name)
173 /* Emit a ttype table reference to a typeinfo object. */
174 DEFHOOK
175 (ttype,
177 bool, (rtx sym),
178 hook_bool_rtx_false)
180 /* Emit an assembler directive to set visibility for the symbol
181 associated with the tree decl. */
182 DEFHOOK
183 (assemble_visibility,
185 void, (tree decl, int visibility),
186 default_assemble_visibility)
188 /* Output the assembler code for entry to a function. */
189 DEFHOOK
190 (function_prologue,
192 void, (FILE *file, HOST_WIDE_INT size),
193 default_function_pro_epilogue)
195 /* Output the assembler code for end of prologue. */
196 DEFHOOK
197 (function_end_prologue,
199 void, (FILE *file),
200 no_asm_to_stream)
202 /* Output the assembler code for start of epilogue. */
203 DEFHOOK
204 (function_begin_epilogue,
206 void, (FILE *file),
207 no_asm_to_stream)
209 /* Output the assembler code for function exit. */
210 DEFHOOK
211 (function_epilogue,
213 void, (FILE *file, HOST_WIDE_INT size),
214 default_function_pro_epilogue)
216 /* Initialize target-specific sections. */
217 DEFHOOK
218 (init_sections,
220 void, (void),
221 hook_void_void)
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,
229 void, (const char *name, unsigned int flags, tree decl),
230 default_no_named_section)
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,
242 section *, (tree decl, enum node_frequency freq, bool startup, bool exit),
243 default_function_section)
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)
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,
263 int, (void),
264 default_reloc_rw_mask)
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,
273 section *, (tree exp, int reloc, unsigned HOST_WIDE_INT align),
274 default_select_section)
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,
281 section *, (enum machine_mode mode, rtx x, unsigned HOST_WIDE_INT align),
282 default_select_rtx_section)
284 /* Select a unique section name for DECL. RELOC is the same as
285 for SELECT_SECTION. */
286 DEFHOOK
287 (unique_section,
289 void, (tree decl, int reloc),
290 default_unique_section)
292 /* Return the readonly data section associated with function DECL. */
293 DEFHOOK
294 (function_rodata_section,
296 section *, (tree decl),
297 default_function_rodata_section)
299 /* Output a constructor for a symbol with a given priority. */
300 DEFHOOK
301 (constructor,
303 void, (rtx symbol, int priority), NULL)
305 /* Output a destructor for a symbol with a given priority. */
306 DEFHOOK
307 (destructor,
309 void, (rtx symbol, int priority), NULL)
311 /* Output the assembler code for a thunk function. THUNK_DECL is the
312 declaration for the thunk function itself, FUNCTION is the decl for
313 the target function. DELTA is an immediate constant offset to be
314 added to THIS. If VCALL_OFFSET is nonzero, the word at
315 *(*this + vcall_offset) should be added to THIS. */
316 DEFHOOK
317 (output_mi_thunk,
319 void, (FILE *file, tree thunk_fndecl, HOST_WIDE_INT delta,
320 HOST_WIDE_INT vcall_offset, tree function),
321 NULL)
323 /* Determine whether output_mi_thunk would succeed. */
324 /* ??? Ideally, this hook would not exist, and success or failure
325 would be returned from output_mi_thunk directly. But there's
326 too much undo-able setup involved in invoking output_mi_thunk.
327 Could be fixed by making output_mi_thunk emit rtl instead of
328 text to the output file. */
329 DEFHOOK
330 (can_output_mi_thunk,
332 bool, (const_tree thunk_fndecl, HOST_WIDE_INT delta,
333 HOST_WIDE_INT vcall_offset, const_tree function),
334 hook_bool_const_tree_hwi_hwi_const_tree_false)
336 /* Output any boilerplate text needed at the beginning of a
337 translation unit. */
338 DEFHOOK
339 (file_start,
341 void, (void),
342 default_file_start)
344 /* Output any boilerplate text needed at the end of a translation unit. */
345 DEFHOOK
346 (file_end,
348 void, (void),
349 hook_void_void)
351 /* Output any boilerplate text needed at the beginning of an
352 LTO output stream. */
353 DEFHOOK
354 (lto_start,
356 void, (void),
357 hook_void_void)
359 /* Output any boilerplate text needed at the end of an
360 LTO output stream. */
361 DEFHOOK
362 (lto_end,
364 void, (void),
365 hook_void_void)
367 /* Output any boilerplace text needed at the end of a
368 translation unit before debug and unwind info is emitted. */
369 DEFHOOK
370 (code_end,
372 void, (void),
373 hook_void_void)
375 /* Output an assembler pseudo-op to declare a library function name
376 external. */
377 DEFHOOK
378 (external_libcall,
380 void, (rtx symref),
381 default_external_libcall)
383 /* Output an assembler directive to mark decl live. This instructs
384 linker to not dead code strip this symbol. */
385 DEFHOOK
386 (mark_decl_preserved,
388 void, (const char *symbol),
389 hook_void_constcharptr)
391 /* Output a record of the command line switches that have been passed. */
392 DEFHOOK
393 (record_gcc_switches,
395 int, (print_switch_type type, const char *text),
396 NULL)
398 /* The name of the section that the example ELF implementation of
399 record_gcc_switches will use to store the information. Target
400 specific versions of record_gcc_switches may or may not use
401 this information. */
402 DEFHOOKPOD
403 (record_gcc_switches_section,
405 const char *, ".GCC.command.line")
407 /* Output the definition of a section anchor. */
408 DEFHOOK
409 (output_anchor,
411 void, (rtx x),
412 default_asm_output_anchor)
414 /* Output a DTP-relative reference to a TLS symbol. */
415 DEFHOOK
416 (output_dwarf_dtprel,
418 void, (FILE *file, int size, rtx x),
419 NULL)
421 /* Some target machines need to postscan each insn after it is output. */
422 DEFHOOK
423 (final_postscan_insn,
425 void, (FILE *file, rtx insn, rtx *opvec, int noperands),
426 NULL)
428 /* Emit the trampoline template. This hook may be NULL. */
429 DEFHOOK
430 (trampoline_template,
432 void, (FILE *f),
433 NULL)
435 DEFHOOK
436 (output_source_filename,
437 "Output COFF information or DWARF debugging information which indicates\
438 that filename @var{name} is the current source file to the stdio\
439 stream @var{file}.\n\
441 This target hook need not be defined if the standard form of output\
442 for the file format in use is appropriate.",
443 void ,(FILE *file, const char *name),
444 default_asm_output_source_filename)
446 DEFHOOK
447 (output_addr_const_extra,
449 bool, (FILE *file, rtx x),
450 default_asm_output_addr_const_extra)
452 /* ??? The TARGET_PRINT_OPERAND* hooks are part of the asm_out struct,
453 even though that is not reflected in the macro name to override their
454 initializers. */
455 #undef HOOK_PREFIX
456 #define HOOK_PREFIX "TARGET_"
458 /* Emit a machine-specific insn operand. */
459 /* ??? tm.texi only documents the old macro PRINT_OPERAND,
460 not this hook, and uses a different name for the argument FILE. */
461 DEFHOOK_UNDOC
462 (print_operand,
464 void, (FILE *file, rtx x, int code),
465 default_print_operand)
467 /* Emit a machine-specific memory address. */
468 /* ??? tm.texi only documents the old macro PRINT_OPERAND_ADDRESS,
469 not this hook, and uses different argument names. */
470 DEFHOOK_UNDOC
471 (print_operand_address,
473 void, (FILE *file, rtx addr),
474 default_print_operand_address)
476 /* Determine whether CODE is a valid punctuation character for the
477 `print_operand' hook. */
478 /* ??? tm.texi only documents the old macro PRINT_OPERAND_PUNCT_VALID_P,
479 not this hook. */
480 DEFHOOK_UNDOC
481 (print_operand_punct_valid_p,
483 bool ,(unsigned char code),
484 default_print_operand_punct_valid_p)
486 /* Given a symbol name, perform same mangling as assemble_name and
487 ASM_OUTPUT_LABELREF, returning result as an IDENTIFIER_NODE. */
488 DEFHOOK
489 (mangle_assembler_name,
490 "Given a symbol @var{name}, perform same mangling as @code{varasm.c}'s\
491 @code{assemble_name}, but in memory rather than to a file stream, returning\
492 result as an @code{IDENTIFIER_NODE}. Required for correct LTO symtabs. The\
493 default implementation calls the @code{TARGET_STRIP_NAME_ENCODING} hook and\
494 then prepends the @code{USER_LABEL_PREFIX}, if any.",
495 tree, (const char *name),
496 default_mangle_assembler_name)
498 HOOK_VECTOR_END (asm_out)
500 /* Functions relating to instruction scheduling. All of these
501 default to null pointers, which haifa-sched.c looks for and handles. */
502 #undef HOOK_PREFIX
503 #define HOOK_PREFIX "TARGET_SCHED_"
504 HOOK_VECTOR (TARGET_SCHED, sched)
506 /* Given the current cost, COST, of an insn, INSN, calculate and
507 return a new cost based on its relationship to DEP_INSN through
508 the dependence LINK. The default is to make no adjustment. */
509 DEFHOOK
510 (adjust_cost,
512 int, (rtx insn, rtx link, rtx dep_insn, int cost), NULL)
514 /* Adjust the priority of an insn as you see fit. Returns the new priority. */
515 DEFHOOK
516 (adjust_priority,
518 int, (rtx insn, int priority), NULL)
520 /* Function which returns the maximum number of insns that can be
521 scheduled in the same machine cycle. This must be constant
522 over an entire compilation. The default is 1. */
523 DEFHOOK
524 (issue_rate,
526 int, (void), NULL)
528 /* Calculate how much this insn affects how many more insns we
529 can emit this cycle. Default is they all cost the same. */
530 DEFHOOK
531 (variable_issue,
533 int, (FILE *file, int verbose, rtx insn, int more), NULL)
535 /* Initialize machine-dependent scheduling code. */
536 DEFHOOK
537 (init,
539 void, (FILE *file, int verbose, int max_ready), NULL)
541 /* Finalize machine-dependent scheduling code. */
542 DEFHOOK
543 (finish,
545 void, (FILE *file, int verbose), NULL)
547 /* Initialize machine-dependent function wide scheduling code. */
548 DEFHOOK
549 (init_global,
551 void, (FILE *file, int verbose, int old_max_uid), NULL)
553 /* Finalize machine-dependent function wide scheduling code. */
554 DEFHOOK
555 (finish_global,
557 void, (FILE *file, int verbose), NULL)
559 /* Reorder insns in a machine-dependent fashion, in two different
560 places. Default does nothing. */
561 DEFHOOK
562 (reorder,
564 int, (FILE *file, int verbose, rtx *ready, int *n_readyp, int clock), NULL)
566 DEFHOOK
567 (reorder2,
569 int, (FILE *file, int verbose, rtx *ready, int *n_readyp, int clock), NULL)
571 /* The following member value is a pointer to a function called
572 after evaluation forward dependencies of insns in chain given
573 by two parameter values (head and tail correspondingly). */
574 DEFHOOK
575 (dependencies_evaluation_hook,
577 void, (rtx head, rtx tail), NULL)
579 /* The values of the following four members are pointers to functions
580 used to simplify the automaton descriptions. dfa_pre_cycle_insn and
581 dfa_post_cycle_insn give functions returning insns which are used to
582 change the pipeline hazard recognizer state when the new simulated
583 processor cycle correspondingly starts and finishes. The function
584 defined by init_dfa_pre_cycle_insn and init_dfa_post_cycle_insn are
585 used to initialize the corresponding insns. The default values of
586 the members result in not changing the automaton state when the
587 new simulated processor cycle correspondingly starts and finishes. */
589 DEFHOOK
590 (init_dfa_pre_cycle_insn,
592 void, (void), NULL)
594 DEFHOOK
595 (dfa_pre_cycle_insn,
597 rtx, (void), NULL)
599 DEFHOOK
600 (init_dfa_post_cycle_insn,
602 void, (void), NULL)
604 DEFHOOK
605 (dfa_post_cycle_insn,
607 rtx, (void), NULL)
609 /* The values of the following two members are pointers to
610 functions used to simplify the automaton descriptions.
611 dfa_pre_advance_cycle and dfa_post_advance_cycle are getting called
612 immediately before and after cycle is advanced. */
614 DEFHOOK
615 (dfa_pre_advance_cycle,
617 void, (void), NULL)
619 DEFHOOK
620 (dfa_post_advance_cycle,
622 void, (void), NULL)
624 /* The following member value is a pointer to a function returning value
625 which defines how many insns in queue `ready' will we try for
626 multi-pass scheduling. If the member value is nonzero and the
627 function returns positive value, the DFA based scheduler will make
628 multi-pass scheduling for the first cycle. In other words, we will
629 try to choose ready insn which permits to start maximum number of
630 insns on the same cycle. */
631 DEFHOOK
632 (first_cycle_multipass_dfa_lookahead,
634 int, (void), NULL)
636 /* The following member value is pointer to a function controlling
637 what insns from the ready insn queue will be considered for the
638 multipass insn scheduling. If the hook returns zero for insn
639 passed as the parameter, the insn will be not chosen to be issued. */
640 DEFHOOK
641 (first_cycle_multipass_dfa_lookahead_guard,
643 int, (rtx insn), NULL)
645 /* This hook prepares the target for a new round of multipass
646 scheduling.
647 DATA is a pointer to target-specific data used for multipass scheduling.
648 READY_TRY and N_READY represent the current state of search in the
649 optimization space. The target can filter out instructions that
650 should not be tried during current round by setting corresponding
651 elements in READY_TRY to non-zero.
652 FIRST_CYCLE_INSN_P is true if this is the first round of multipass
653 scheduling on current cycle. */
654 DEFHOOK
655 (first_cycle_multipass_begin,
657 void, (void *data, char *ready_try, int n_ready, bool first_cycle_insn_p),
658 NULL)
660 /* This hook is called when multipass scheduling evaluates instruction INSN.
661 DATA is a pointer to target-specific data that can be used to record effects
662 of INSN on CPU that are not described in DFA.
663 READY_TRY and N_READY represent the current state of search in the
664 optimization space. The target can filter out instructions that
665 should not be tried after issueing INSN by setting corresponding
666 elements in READY_TRY to non-zero.
667 INSN is the instruction being evaluated.
668 PREV_DATA is a pointer to target-specific data corresponding
669 to a state before issueing INSN. */
670 DEFHOOK
671 (first_cycle_multipass_issue,
673 void, (void *data, char *ready_try, int n_ready, rtx insn,
674 const void *prev_data), NULL)
676 /* This hook is called when multipass scheduling backtracks from evaluation of
677 instruction corresponding to DATA.
678 DATA is a pointer to target-specific data that stores the effects
679 of instruction from which the algorithm backtracks on CPU that are not
680 described in DFA.
681 READY_TRY and N_READY represent the current state of search in the
682 optimization space. The target can filter out instructions that
683 should not be tried after issueing INSN by setting corresponding
684 elements in READY_TRY to non-zero. */
685 DEFHOOK
686 (first_cycle_multipass_backtrack,
688 void, (const void *data, char *ready_try, int n_ready), NULL)
690 /* This hook notifies the target about the result of the concluded current
691 round of multipass scheduling.
692 DATA is a pointer.
693 If DATA is non-NULL it points to target-specific data used for multipass
694 scheduling which corresponds to instruction at the start of the chain of
695 the winning solution. DATA is NULL when multipass scheduling cannot find
696 a good enough solution on current cycle and decides to retry later,
697 usually after advancing the cycle count. */
698 DEFHOOK
699 (first_cycle_multipass_end,
701 void, (const void *data), NULL)
703 /* This hook is called to initialize target-specific data for multipass
704 scheduling after it has been allocated.
705 DATA is a pointer to target-specific data that stores the effects
706 of instruction from which the algorithm backtracks on CPU that are not
707 described in DFA. */
708 DEFHOOK
709 (first_cycle_multipass_init,
711 void, (void *data), NULL)
713 /* This hook is called to finalize target-specific data for multipass
714 scheduling before it is deallocated.
715 DATA is a pointer to target-specific data that stores the effects
716 of instruction from which the algorithm backtracks on CPU that are not
717 described in DFA. */
718 DEFHOOK
719 (first_cycle_multipass_fini,
721 void, (void *data), NULL)
723 /* The following member value is pointer to a function called by
724 the insn scheduler before issuing insn passed as the third
725 parameter on given cycle. If the hook returns nonzero, the
726 insn is not issued on given processors cycle. Instead of that,
727 the processor cycle is advanced. If the value passed through
728 the last parameter is zero, the insn ready queue is not sorted
729 on the new cycle start as usually. The first parameter passes
730 file for debugging output. The second one passes the scheduler
731 verbose level of the debugging output. The forth and the fifth
732 parameter values are correspondingly processor cycle on which
733 the previous insn has been issued and the current processor cycle. */
734 DEFHOOK
735 (dfa_new_cycle,
737 int, (FILE *dump, int verbose, rtx insn, int last_clock,
738 int clock, int *sort_p),
739 NULL)
741 /* The following member value is a pointer to a function called by the
742 insn scheduler. It should return true if there exists a dependence
743 which is considered costly by the target, between the insn
744 DEP_PRO (&_DEP), and the insn DEP_CON (&_DEP). The first parameter is
745 the dep that represents the dependence between the two insns. The
746 second argument is the cost of the dependence as estimated by
747 the scheduler. The last argument is the distance in cycles
748 between the already scheduled insn (first parameter) and the
749 second insn (second parameter). */
750 DEFHOOK
751 (is_costly_dependence,
753 bool, (struct _dep *_dep, int cost, int distance), NULL)
755 DEFHOOK_UNDOC
756 (adjust_cost_2,
757 "Given the current cost, @var{cost}, of an insn, @var{insn}, calculate and\
758 return a new cost based on its relationship to @var{dep_insn} through the\
759 dependence of weakness @var{dw}. The default is to make no adjustment.",
760 int, (rtx insn, int dep_type1, rtx dep_insn, int cost, int dw), NULL)
762 /* The following member value is a pointer to a function called
763 by the insn scheduler. This hook is called to notify the backend
764 that new instructions were emitted. */
765 DEFHOOK
766 (h_i_d_extended,
768 void, (void), NULL)
770 /* Next 5 functions are for multi-point scheduling. */
772 /* Allocate memory for scheduler context. */
773 DEFHOOK
774 (alloc_sched_context,
776 void *, (void), NULL)
778 /* Fills the context from the local machine scheduler context. */
779 DEFHOOK
780 (init_sched_context,
782 void, (void *tc, bool clean_p), NULL)
784 /* Sets local machine scheduler context to a saved value. */
785 DEFHOOK
786 (set_sched_context,
788 void, (void *tc), NULL)
790 /* Clears a scheduler context so it becomes like after init. */
791 DEFHOOK
792 (clear_sched_context,
794 void, (void *tc), NULL)
796 /* Frees the scheduler context. */
797 DEFHOOK
798 (free_sched_context,
800 void, (void *tc), NULL)
802 /* The following member value is a pointer to a function called
803 by the insn scheduler.
804 The first parameter is an instruction, the second parameter is the type
805 of the requested speculation, and the third parameter is a pointer to the
806 speculative pattern of the corresponding type (set if return value == 1).
807 It should return
808 -1, if there is no pattern, that will satisfy the requested speculation type,
809 0, if current pattern satisfies the requested speculation type,
810 1, if pattern of the instruction should be changed to the newly
811 generated one. */
812 DEFHOOK
813 (speculate_insn,
815 int, (rtx insn, int request, rtx *new_pat), NULL)
817 /* The following member value is a pointer to a function called
818 by the insn scheduler. It should return true if the check instruction
819 passed as the parameter needs a recovery block. */
820 DEFHOOK
821 (needs_block_p,
823 bool, (int dep_status), NULL)
825 /* The following member value is a pointer to a function called
826 by the insn scheduler. It should return a pattern for the check
827 instruction.
828 The first parameter is a speculative instruction, the second parameter
829 is the label of the corresponding recovery block (or null, if it is a
830 simple check). If the mutation of the check is requested (e.g. from
831 ld.c to chk.a), the third parameter is true - in this case the first
832 parameter is the previous check. */
833 DEFHOOK
834 (gen_spec_check,
836 rtx, (rtx insn, rtx label, int mutate_p), NULL)
838 /* The following member value is a pointer to a function controlling
839 what insns from the ready insn queue will be considered for the
840 multipass insn scheduling. If the hook returns zero for the insn
841 passed as the parameter, the insn will not be chosen to be
842 issued. This hook is used to discard speculative instructions,
843 that stand at the first position of the ready list. */
844 DEFHOOK
845 (first_cycle_multipass_dfa_lookahead_guard_spec,
847 bool, (const_rtx insn), NULL)
849 /* The following member value is a pointer to a function that provides
850 information about the speculation capabilities of the target.
851 The parameter is a pointer to spec_info variable. */
852 DEFHOOK
853 (set_sched_flags,
855 void, (struct spec_info_def *spec_info), NULL)
857 DEFHOOK_UNDOC
858 (get_insn_spec_ds,
859 "Return speculation types of instruction @var{insn}.",
860 int, (rtx insn), NULL)
862 DEFHOOK_UNDOC
863 (get_insn_checked_ds,
864 "Return speculation types that are checked for instruction @var{insn}",
865 int, (rtx insn), NULL)
867 DEFHOOK_UNDOC
868 (skip_rtx_p,
869 "Return bool if rtx scanning should just skip current layer and\
870 advance to the inner rtxes.",
871 bool, (const_rtx x), NULL)
873 /* The following member value is a pointer to a function that provides
874 information about the target resource-based lower bound which is
875 used by the swing modulo scheduler. The parameter is a pointer
876 to ddg variable. */
877 DEFHOOK
878 (sms_res_mii,
880 int, (struct ddg *g), NULL)
882 /* The following member value is a function that initializes dispatch
883 schedling and adds instructions to dispatch window according to its
884 parameters. */
885 DEFHOOK
886 (dispatch_do,
888 void, (rtx insn, int x),
889 hook_void_rtx_int)
891 /* The following member value is a a function that returns true is
892 dispatch schedling is supported in hardware and condition passed
893 as the second parameter is true. */
894 DEFHOOK
895 (dispatch,
897 bool, (rtx insn, int x),
898 hook_bool_rtx_int_false)
900 HOOK_VECTOR_END (sched)
902 /* Functions relating to vectorization. */
903 #undef HOOK_PREFIX
904 #define HOOK_PREFIX "TARGET_VECTORIZE_"
905 HOOK_VECTOR (TARGET_VECTORIZE, vectorize)
907 /* The following member value is a pointer to a function called
908 by the vectorizer, and return the decl of the target builtin
909 function. */
910 DEFHOOK
911 (builtin_mask_for_load,
913 tree, (void), NULL)
915 /* Returns a code for builtin that realizes vectorized version of
916 function, or NULL_TREE if not available. */
917 DEFHOOK
918 (builtin_vectorized_function,
920 tree, (tree fndecl, tree vec_type_out, tree vec_type_in),
921 default_builtin_vectorized_function)
923 /* Returns a function declaration for a builtin that realizes the
924 vector conversion, or NULL_TREE if not available. */
925 DEFHOOK
926 (builtin_conversion,
928 tree, (unsigned code, tree dest_type, tree src_type),
929 default_builtin_vectorized_conversion)
931 /* Target builtin that implements vector widening multiplication.
932 builtin_mul_widen_eve computes the element-by-element products
933 for the even elements, and builtin_mul_widen_odd computes the
934 element-by-element products for the odd elements. */
935 DEFHOOK
936 (builtin_mul_widen_even,
938 tree, (tree x), NULL)
940 DEFHOOK
941 (builtin_mul_widen_odd,
943 tree, (tree x), NULL)
945 /* Cost of different vector/scalar statements in vectorization cost
946 model. In case of misaligned vector loads and stores the cost depends
947 on the data type and misalignment value. */
948 DEFHOOK
949 (builtin_vectorization_cost,
951 int, (enum vect_cost_for_stmt type_of_cost, tree vectype, int misalign),
952 default_builtin_vectorization_cost)
954 /* Return true if vector alignment is reachable (by peeling N
955 iterations) for the given type. */
956 DEFHOOK
957 (vector_alignment_reachable,
959 bool, (const_tree type, bool is_packed),
960 default_builtin_vector_alignment_reachable)
962 /* Target builtin that implements vector permute. */
963 DEFHOOK
964 (builtin_vec_perm,
966 tree, (tree type, tree *mask_element_type), NULL)
968 /* Return true if a vector created for builtin_vec_perm is valid. */
969 DEFHOOK
970 (builtin_vec_perm_ok,
972 bool, (tree vec_type, tree mask),
973 hook_bool_tree_tree_true)
975 /* Return true if the target supports misaligned store/load of a
976 specific factor denoted in the third parameter. The last parameter
977 is true if the access is defined in a packed struct. */
978 DEFHOOK
979 (support_vector_misalignment,
981 bool,
982 (enum machine_mode mode, const_tree type, int misalignment, bool is_packed),
983 default_builtin_support_vector_misalignment)
985 /* Returns the preferred mode for SIMD operations for the specified
986 scalar mode. */
987 DEFHOOK
988 (preferred_simd_mode,
990 enum machine_mode,
991 (enum machine_mode mode),
992 default_preferred_simd_mode)
994 /* Returns a mask of vector sizes to iterate over when auto-vectorizing
995 after processing the preferred one derived from preferred_simd_mode. */
996 DEFHOOK
997 (autovectorize_vector_sizes,
999 unsigned int,
1000 (void),
1001 default_autovectorize_vector_sizes)
1003 HOOK_VECTOR_END (vectorize)
1005 #undef HOOK_PREFIX
1006 #define HOOK_PREFIX "TARGET_"
1008 /* The initial value of target_flags. */
1009 DEFHOOKPOD
1010 (default_target_flags,
1012 int, 0)
1014 /* Allow target specific overriding of option settings after options have
1015 been changed by an attribute or pragma or when it is reset at the
1016 end of the code affected by an attribute or pragma. */
1017 DEFHOOK
1018 (override_options_after_change,
1020 void, (void),
1021 hook_void_void)
1023 /* Handle target switch DECODED for options structures OPTS and
1024 OPTS_SET, at location LOC. Return true if the switch was valid. */
1025 DEFHOOK
1026 (handle_option,
1028 bool, (struct gcc_options *opts, struct gcc_options *opts_set,
1029 const struct cl_decoded_option *decoded,
1030 unsigned int /*location_t*/ loc),
1031 default_target_handle_option)
1033 /* Display extra, target specific information in response to a
1034 --target-help switch. */
1035 DEFHOOK
1036 (help,
1038 void, (void), NULL)
1040 DEFHOOK_UNDOC
1041 (eh_return_filter_mode,
1042 "Return machine mode for filter value.",
1043 enum machine_mode, (void),
1044 default_eh_return_filter_mode)
1046 /* Return machine mode for libgcc expanded cmp instructions. */
1047 DEFHOOK
1048 (libgcc_cmp_return_mode,
1050 enum machine_mode, (void),
1051 default_libgcc_cmp_return_mode)
1053 /* Return machine mode for libgcc expanded shift instructions. */
1054 DEFHOOK
1055 (libgcc_shift_count_mode,
1057 enum machine_mode, (void),
1058 default_libgcc_shift_count_mode)
1060 /* Return machine mode to be used for _Unwind_Word type. */
1061 DEFHOOK
1062 (unwind_word_mode,
1064 enum machine_mode, (void),
1065 default_unwind_word_mode)
1067 /* Given two decls, merge their attributes and return the result. */
1068 DEFHOOK
1069 (merge_decl_attributes,
1071 tree, (tree olddecl, tree newdecl),
1072 merge_decl_attributes)
1074 /* Given two types, merge their attributes and return the result. */
1075 DEFHOOK
1076 (merge_type_attributes,
1078 tree, (tree type1, tree type2),
1079 merge_type_attributes)
1081 /* Table of machine attributes and functions to handle them.
1082 Ignored if NULL. */
1083 DEFHOOKPOD
1084 (attribute_table,
1086 const struct attribute_spec *, NULL)
1088 /* Return true iff attribute NAME expects a plain identifier as its first
1089 argument. */
1090 DEFHOOK
1091 (attribute_takes_identifier_p,
1093 bool, (const_tree name),
1094 hook_bool_const_tree_false)
1096 /* Return zero if the attributes on TYPE1 and TYPE2 are incompatible,
1097 one if they are compatible and two if they are nearly compatible
1098 (which causes a warning to be generated). */
1099 DEFHOOK
1100 (comp_type_attributes,
1102 int, (const_tree type1, const_tree type2),
1103 hook_int_const_tree_const_tree_1)
1105 /* Assign default attributes to the newly defined TYPE. */
1106 DEFHOOK
1107 (set_default_type_attributes,
1109 void, (tree type),
1110 hook_void_tree)
1112 /* Insert attributes on the newly created DECL. */
1113 DEFHOOK
1114 (insert_attributes,
1116 void, (tree node, tree *attr_ptr),
1117 hook_void_tree_treeptr)
1119 /* Return true if FNDECL (which has at least one machine attribute)
1120 can be inlined despite its machine attributes, false otherwise. */
1121 DEFHOOK
1122 (function_attribute_inlinable_p,
1124 bool, (const_tree fndecl),
1125 hook_bool_const_tree_false)
1127 /* Return true if bitfields in RECORD_TYPE should follow the
1128 Microsoft Visual C++ bitfield layout rules. */
1129 DEFHOOK
1130 (ms_bitfield_layout_p,
1132 bool, (const_tree record_type),
1133 hook_bool_const_tree_false)
1135 /* For now this is only an interface to WORDS_BIG_ENDIAN for
1136 target-independent code like the front ends, need performance testing
1137 before switching completely to the target hook. */
1138 DEFHOOK_UNDOC
1139 (words_big_endian,
1141 bool, (void),
1142 targhook_words_big_endian)
1144 /* Likewise for FLOAT_WORDS_BIG_ENDIAN. */
1145 DEFHOOK_UNDOC
1146 (float_words_big_endian,
1148 bool, (void),
1149 targhook_float_words_big_endian)
1151 /* True if the target supports decimal floating point. */
1152 DEFHOOK
1153 (decimal_float_supported_p,
1155 bool, (void),
1156 default_decimal_float_supported_p)
1158 /* True if the target supports fixed-point. */
1159 DEFHOOK
1160 (fixed_point_supported_p,
1162 bool, (void),
1163 default_fixed_point_supported_p)
1165 /* Return true if anonymous bitfields affect structure alignment. */
1166 DEFHOOK
1167 (align_anon_bitfield,
1169 bool, (void),
1170 hook_bool_void_false)
1172 /* Return true if volatile bitfields should use the narrowest type possible.
1173 Return false if they should use the container type. */
1174 DEFHOOK
1175 (narrow_volatile_bitfield,
1177 bool, (void),
1178 hook_bool_void_false)
1180 /* Set up target-specific built-in functions. */
1181 DEFHOOK
1182 (init_builtins,
1184 void, (void),
1185 hook_void_void)
1187 /* Initialize (if INITIALIZE_P is true) and return the target-specific
1188 built-in function decl for CODE.
1189 Return NULL if that is not possible. Return error_mark_node if CODE
1190 is outside of the range of valid target builtin function codes. */
1191 DEFHOOK
1192 (builtin_decl,
1194 tree, (unsigned code, bool initialize_p), NULL)
1196 /* Expand a target-specific builtin. */
1197 DEFHOOK
1198 (expand_builtin,
1200 rtx,
1201 (tree exp, rtx target, rtx subtarget, enum machine_mode mode, int ignore),
1202 default_expand_builtin)
1204 /* Select a replacement for a target-specific builtin. This is done
1205 *before* regular type checking, and so allows the target to
1206 implement a crude form of function overloading. The result is a
1207 complete expression that implements the operation. PARAMS really
1208 has type VEC(tree,gc)*, but we don't want to include tree.h here. */
1209 DEFHOOK
1210 (resolve_overloaded_builtin,
1212 tree, (unsigned int /*location_t*/ loc, tree fndecl, void *arglist), NULL)
1214 /* Fold a target-specific builtin. */
1215 DEFHOOK
1216 (fold_builtin,
1218 tree, (tree fndecl, int n_args, tree *argp, bool ignore),
1219 hook_tree_tree_int_treep_bool_null)
1221 /* Returns a code for a target-specific builtin that implements
1222 reciprocal of the function, or NULL_TREE if not available. */
1223 DEFHOOK
1224 (builtin_reciprocal,
1226 tree, (unsigned fn, bool md_fn, bool sqrt),
1227 default_builtin_reciprocal)
1229 /* For a vendor-specific TYPE, return a pointer to a statically-allocated
1230 string containing the C++ mangling for TYPE. In all other cases, return
1231 NULL. */
1232 DEFHOOK
1233 (mangle_type,
1235 const char *, (const_tree type),
1236 hook_constcharptr_const_tree_null)
1238 /* Make any adjustments to libfunc names needed for this target. */
1239 DEFHOOK
1240 (init_libfuncs,
1242 void, (void),
1243 hook_void_void)
1245 /* Given a decl, a section name, and whether the decl initializer
1246 has relocs, choose attributes for the section. */
1247 /* ??? Should be merged with SELECT_SECTION and UNIQUE_SECTION. */
1248 DEFHOOK
1249 (section_type_flags,
1251 unsigned int, (tree decl, const char *name, int reloc),
1252 default_section_type_flags)
1254 /* True if new jumps cannot be created, to replace existing ones or
1255 not, at the current point in the compilation. */
1256 DEFHOOK
1257 (cannot_modify_jumps_p,
1259 bool, (void),
1260 hook_bool_void_false)
1262 /* Return a register class for which branch target register
1263 optimizations should be applied. */
1264 DEFHOOK
1265 (branch_target_register_class,
1267 reg_class_t, (void),
1268 default_branch_target_register_class)
1270 /* Return true if branch target register optimizations should include
1271 callee-saved registers that are not already live during the current
1272 function. AFTER_PE_GEN is true if prologues and epilogues have
1273 already been generated. */
1274 DEFHOOK
1275 (branch_target_register_callee_saved,
1277 bool, (bool after_prologue_epilogue_gen),
1278 hook_bool_bool_false)
1280 /* Return true if the target supports conditional execution. */
1281 DEFHOOK
1282 (have_conditional_execution,
1284 bool, (void),
1285 default_have_conditional_execution)
1287 /* Return a new value for loop unroll size. */
1288 DEFHOOK
1289 (loop_unroll_adjust,
1291 unsigned, (unsigned nunroll, struct loop *loop),
1292 NULL)
1294 /* True if the constant X cannot be placed in the constant pool. */
1295 DEFHOOK
1296 (cannot_force_const_mem,
1298 bool, (rtx x),
1299 hook_bool_rtx_false)
1301 DEFHOOK_UNDOC
1302 (cannot_copy_insn_p,
1303 "True if the insn @var{x} cannot be duplicated.",
1304 bool, (rtx), NULL)
1306 /* True if X is considered to be commutative. */
1307 DEFHOOK
1308 (commutative_p,
1310 bool, (const_rtx x, int outer_code),
1311 hook_bool_const_rtx_commutative_p)
1313 /* True if ADDR is an address-expression whose effect depends
1314 on the mode of the memory reference it is used in. */
1315 DEFHOOK
1316 (mode_dependent_address_p,
1318 bool, (const_rtx addr),
1319 default_mode_dependent_address_p)
1321 /* Given an invalid address X for a given machine mode, try machine-specific
1322 ways to make it legitimate. Return X or an invalid address on failure. */
1323 DEFHOOK
1324 (legitimize_address,
1326 rtx, (rtx x, rtx oldx, enum machine_mode mode),
1327 default_legitimize_address)
1329 /* Given an address RTX, undo the effects of LEGITIMIZE_ADDRESS. */
1330 DEFHOOK
1331 (delegitimize_address,
1333 rtx, (rtx x),
1334 delegitimize_mem_from_attrs)
1336 /* Given an address RTX, say whether it is valid. */
1337 DEFHOOK
1338 (legitimate_address_p,
1340 bool, (enum machine_mode mode, rtx x, bool strict),
1341 default_legitimate_address_p)
1343 /* True if the given constant can be put into an object_block. */
1344 DEFHOOK
1345 (use_blocks_for_constant_p,
1347 bool, (enum machine_mode mode, const_rtx x),
1348 hook_bool_mode_const_rtx_false)
1350 /* The minimum and maximum byte offsets for anchored addresses. */
1351 DEFHOOKPOD
1352 (min_anchor_offset,
1354 HOST_WIDE_INT, 0)
1356 DEFHOOKPOD
1357 (max_anchor_offset,
1359 HOST_WIDE_INT, 0)
1361 /* True if section anchors can be used to access the given symbol. */
1362 DEFHOOK
1363 (use_anchors_for_symbol_p,
1365 bool, (const_rtx x),
1366 default_use_anchors_for_symbol_p)
1368 /* True if it is OK to do sibling call optimization for the specified
1369 call expression EXP. DECL will be the called function, or NULL if
1370 this is an indirect call. */
1371 DEFHOOK
1372 (function_ok_for_sibcall,
1374 bool, (tree decl, tree exp),
1375 hook_bool_tree_tree_false)
1377 /* Establish appropriate back-end context for processing the function
1378 FNDECL. The argument might be NULL to indicate processing at top
1379 level, outside of any function scope. */
1380 DEFHOOK
1381 (set_current_function,
1383 void, (tree decl), hook_void_tree)
1385 /* True if EXP should be placed in a "small data" section. */
1386 DEFHOOK
1387 (in_small_data_p,
1389 bool, (const_tree exp),
1390 hook_bool_const_tree_false)
1392 /* True if EXP names an object for which name resolution must resolve
1393 to the current executable or shared library. */
1394 DEFHOOK
1395 (binds_local_p,
1397 bool, (const_tree exp),
1398 default_binds_local_p)
1400 /* Check if profiling code is before or after prologue. */
1401 DEFHOOK
1402 (profile_before_prologue,
1403 "It returns true if target wants profile code emitted before prologue.\n\n\
1404 The default version of this hook use the target macro\n\
1405 @code{PROFILE_BEFORE_PROLOGUE}.",
1406 bool, (void),
1407 default_profile_before_prologue)
1409 /* Modify and return the identifier of a DECL's external name,
1410 originally identified by ID, as required by the target,
1411 (eg, append @nn to windows32 stdcall function names).
1412 The default is to return ID without modification. */
1413 DEFHOOK
1414 (mangle_decl_assembler_name,
1416 tree, (tree decl, tree id),
1417 default_mangle_decl_assembler_name)
1419 /* Do something target-specific to record properties of the DECL into
1420 the associated SYMBOL_REF. */
1421 DEFHOOK
1422 (encode_section_info,
1424 void, (tree decl, rtx rtl, int new_decl_p),
1425 default_encode_section_info)
1427 /* Undo the effects of encode_section_info on the symbol string. */
1428 DEFHOOK
1429 (strip_name_encoding,
1431 const char *, (const char *name),
1432 default_strip_name_encoding)
1434 /* If shift optabs for MODE are known to always truncate the shift count,
1435 return the mask that they apply. Return 0 otherwise. */
1436 DEFHOOK
1437 (shift_truncation_mask,
1439 unsigned HOST_WIDE_INT, (enum machine_mode mode),
1440 default_shift_truncation_mask)
1442 /* Return the number of divisions in the given MODE that should be present,
1443 so that it is profitable to turn the division into a multiplication by
1444 the reciprocal. */
1445 DEFHOOK
1446 (min_divisions_for_recip_mul,
1448 unsigned int, (enum machine_mode mode),
1449 default_min_divisions_for_recip_mul)
1451 /* If the representation of integral MODE is such that values are
1452 always sign-extended to a wider mode MODE_REP then return
1453 SIGN_EXTEND. Return UNKNOWN otherwise. */
1454 /* Note that the return type ought to be RTX_CODE, but that's not
1455 necessarily defined at this point. */
1456 DEFHOOK
1457 (mode_rep_extended,
1459 int, (enum machine_mode mode, enum machine_mode rep_mode),
1460 default_mode_rep_extended)
1462 /* True if MODE is valid for a pointer in __attribute__((mode("MODE"))). */
1463 DEFHOOK
1464 (valid_pointer_mode,
1466 bool, (enum machine_mode mode),
1467 default_valid_pointer_mode)
1469 /* Disambiguate with errno. */
1470 DEFHOOK
1471 (ref_may_alias_errno,
1472 "Define this to return nonzero if the memory reference @var{ref}\
1473 may alias with the system C library errno location. The default\
1474 version of this hook assumes the system C library errno location\
1475 is either a declaration of type int or accessed by dereferencing\
1476 a pointer to int.",
1477 bool, (struct ao_ref_s *ref),
1478 default_ref_may_alias_errno)
1480 /* Support for named address spaces. */
1481 #undef HOOK_PREFIX
1482 #define HOOK_PREFIX "TARGET_ADDR_SPACE_"
1483 HOOK_VECTOR (TARGET_ADDR_SPACE_HOOKS, addr_space)
1485 /* MODE to use for a pointer into another address space. */
1486 DEFHOOK
1487 (pointer_mode,
1489 enum machine_mode, (addr_space_t address_space),
1490 default_addr_space_pointer_mode)
1492 /* MODE to use for an address in another address space. */
1493 DEFHOOK
1494 (address_mode,
1496 enum machine_mode, (addr_space_t address_space),
1497 default_addr_space_address_mode)
1499 /* True if MODE is valid for a pointer in __attribute__((mode("MODE")))
1500 in another address space. */
1501 DEFHOOK
1502 (valid_pointer_mode,
1504 bool, (enum machine_mode mode, addr_space_t as),
1505 default_addr_space_valid_pointer_mode)
1507 /* True if an address is a valid memory address to a given named address
1508 space for a given mode. */
1509 DEFHOOK
1510 (legitimate_address_p,
1512 bool, (enum machine_mode mode, rtx exp, bool strict, addr_space_t as),
1513 default_addr_space_legitimate_address_p)
1515 /* Return an updated address to convert an invalid pointer to a named
1516 address space to a valid one. If NULL_RTX is returned use machine
1517 independent methods to make the address valid. */
1518 DEFHOOK
1519 (legitimize_address,
1521 rtx, (rtx x, rtx oldx, enum machine_mode mode, addr_space_t as),
1522 default_addr_space_legitimize_address)
1524 /* True if one named address space is a subset of another named address. */
1525 DEFHOOK
1526 (subset_p,
1528 bool, (addr_space_t superset, addr_space_t subset),
1529 default_addr_space_subset_p)
1531 /* Function to convert an rtl expression from one address space to another. */
1532 DEFHOOK
1533 (convert,
1535 rtx, (rtx op, tree from_type, tree to_type),
1536 default_addr_space_convert)
1538 HOOK_VECTOR_END (addr_space)
1540 #undef HOOK_PREFIX
1541 #define HOOK_PREFIX "TARGET_"
1543 /* True if MODE is valid for the target. By "valid", we mean able to
1544 be manipulated in non-trivial ways. In particular, this means all
1545 the arithmetic is supported. */
1546 DEFHOOK
1547 (scalar_mode_supported_p,
1549 bool, (enum machine_mode mode),
1550 default_scalar_mode_supported_p)
1552 /* Similarly for vector modes. "Supported" here is less strict. At
1553 least some operations are supported; need to check optabs or builtins
1554 for further details. */
1555 DEFHOOK
1556 (vector_mode_supported_p,
1558 bool, (enum machine_mode mode),
1559 hook_bool_mode_false)
1561 /* Compute cost of moving data from a register of class FROM to one of
1562 TO, using MODE. */
1563 DEFHOOK
1564 (register_move_cost,
1566 int, (enum machine_mode mode, reg_class_t from, reg_class_t to),
1567 default_register_move_cost)
1569 /* Compute cost of moving registers to/from memory. */
1570 /* ??? Documenting the argument types for this hook requires a GFDL
1571 license grant. Also, the documentation uses a different name for RCLASS. */
1572 DEFHOOK
1573 (memory_move_cost,
1575 int, (enum machine_mode mode, reg_class_t rclass, bool in),
1576 default_memory_move_cost)
1578 /* True for MODE if the target expects that registers in this mode will
1579 be allocated to registers in a small register class. The compiler is
1580 allowed to use registers explicitly used in the rtl as spill registers
1581 but it should prevent extending the lifetime of these registers. */
1582 DEFHOOK
1583 (small_register_classes_for_mode_p,
1585 bool, (enum machine_mode mode),
1586 hook_bool_mode_false)
1588 /* Register number for a flags register. Only needs to be defined if the
1589 target is constrainted to use post-reload comparison elimination. */
1590 DEFHOOKPOD
1591 (flags_regnum,
1592 "If the target has a dedicated flags register, and it needs to use the\
1593 post-reload comparison elimination pass, then this value should be set\
1594 appropriately.",
1595 unsigned int, INVALID_REGNUM)
1597 /* Compute a (partial) cost for rtx X. Return true if the complete
1598 cost has been computed, and false if subexpressions should be
1599 scanned. In either case, *TOTAL contains the cost result. */
1600 /* Note that CODE and OUTER_CODE ought to be RTX_CODE, but that's
1601 not necessarily defined at this point. */
1602 DEFHOOK
1603 (rtx_costs,
1605 bool, (rtx x, int code, int outer_code, int *total, bool speed),
1606 hook_bool_rtx_int_int_intp_bool_false)
1608 /* Compute the cost of X, used as an address. Never called with
1609 invalid addresses. */
1610 DEFHOOK
1611 (address_cost,
1613 int, (rtx address, bool speed),
1614 default_address_cost)
1616 /* Return where to allocate pseudo for a given hard register initial value. */
1617 DEFHOOK
1618 (allocate_initial_value,
1620 rtx, (rtx hard_reg), NULL)
1622 /* Return nonzero if evaluating UNSPEC[_VOLATILE] X might cause a trap.
1623 FLAGS has the same meaning as in rtlanal.c: may_trap_p_1. */
1624 DEFHOOK
1625 (unspec_may_trap_p,
1627 int, (const_rtx x, unsigned flags),
1628 default_unspec_may_trap_p)
1630 /* Given a register, this hook should return a parallel of registers
1631 to represent where to find the register pieces. Define this hook
1632 if the register and its mode are represented in Dwarf in
1633 non-contiguous locations, or if the register should be
1634 represented in more than one register in Dwarf. Otherwise, this
1635 hook should return NULL_RTX. */
1636 DEFHOOK
1637 (dwarf_register_span,
1639 rtx, (rtx reg),
1640 hook_rtx_rtx_null)
1642 /* If expand_builtin_init_dwarf_reg_sizes needs to fill in table
1643 entries not corresponding directly to registers below
1644 FIRST_PSEUDO_REGISTER, this hook should generate the necessary
1645 code, given the address of the table. */
1646 DEFHOOK
1647 (init_dwarf_reg_sizes_extra,
1649 void, (tree address),
1650 hook_void_tree)
1652 /* Fetch the fixed register(s) which hold condition codes, for
1653 targets where it makes sense to look for duplicate assignments to
1654 the condition codes. This should return true if there is such a
1655 register, false otherwise. The arguments should be set to the
1656 fixed register numbers. Up to two condition code registers are
1657 supported. If there is only one for this target, the int pointed
1658 at by the second argument should be set to -1. */
1659 DEFHOOK
1660 (fixed_condition_code_regs,
1662 bool, (unsigned int *p1, unsigned int *p2),
1663 hook_bool_uintp_uintp_false)
1665 /* If two condition code modes are compatible, return a condition
1666 code mode which is compatible with both, such that a comparison
1667 done in the returned mode will work for both of the original
1668 modes. If the condition code modes are not compatible, return
1669 VOIDmode. */
1670 DEFHOOK
1671 (cc_modes_compatible,
1673 enum machine_mode, (enum machine_mode m1, enum machine_mode m2),
1674 default_cc_modes_compatible)
1676 /* Do machine-dependent code transformations. Called just before
1677 delayed-branch scheduling. */
1678 DEFHOOK
1679 (machine_dependent_reorg,
1681 void, (void), NULL)
1683 /* Create the __builtin_va_list type. */
1684 DEFHOOK
1685 (build_builtin_va_list,
1687 tree, (void),
1688 std_build_builtin_va_list)
1690 /* Enumerate the va list variants. */
1691 DEFHOOK
1692 (enum_va_list_p,
1694 int, (int idx, const char **pname, tree *ptree),
1695 NULL)
1697 /* Get the cfun/fndecl calling abi __builtin_va_list type. */
1698 DEFHOOK
1699 (fn_abi_va_list,
1701 tree, (tree fndecl),
1702 std_fn_abi_va_list)
1704 /* Get the __builtin_va_list type dependent on input type. */
1705 DEFHOOK
1706 (canonical_va_list_type,
1708 tree, (tree type),
1709 std_canonical_va_list_type)
1711 /* ??? Documenting this hook requires a GFDL license grant. */
1712 DEFHOOK_UNDOC
1713 (expand_builtin_va_start,
1714 "Expand the @code{__builtin_va_start} builtin.",
1715 void, (tree valist, rtx nextarg), NULL)
1717 /* Gimplifies a VA_ARG_EXPR. */
1718 DEFHOOK
1719 (gimplify_va_arg_expr,
1721 tree, (tree valist, tree type, gimple_seq *pre_p, gimple_seq *post_p),
1722 std_gimplify_va_arg_expr)
1724 /* Validity-checking routines for PCH files, target-specific.
1725 get_pch_validity returns a pointer to the data to be stored,
1726 and stores the size in its argument. pch_valid_p gets the same
1727 information back and returns NULL if the PCH is valid,
1728 or an error message if not. */
1729 DEFHOOK
1730 (get_pch_validity,
1732 void *, (size_t *sz),
1733 default_get_pch_validity)
1735 DEFHOOK
1736 (pch_valid_p,
1738 const char *, (const void *data, size_t sz),
1739 default_pch_valid_p)
1741 /* If nonnull, this function checks whether a PCH file with the
1742 given set of target flags can be used. It returns NULL if so,
1743 otherwise it returns an error message. */
1744 DEFHOOK
1745 (check_pch_target_flags,
1747 const char *, (int pch_flags), NULL)
1749 /* True if the compiler should give an enum type only as many
1750 bytes as it takes to represent the range of possible values of
1751 that type. */
1752 DEFHOOK
1753 (default_short_enums,
1755 bool, (void),
1756 hook_bool_void_false)
1758 /* This target hook returns an rtx that is used to store the address
1759 of the current frame into the built-in setjmp buffer. */
1760 DEFHOOK
1761 (builtin_setjmp_frame_value,
1763 rtx, (void),
1764 default_builtin_setjmp_frame_value)
1766 /* This target hook should add STRING_CST trees for any hard regs
1767 the port wishes to automatically clobber for an asm. */
1768 DEFHOOK
1769 (md_asm_clobbers,
1771 tree, (tree outputs, tree inputs, tree clobbers),
1772 hook_tree_tree_tree_tree_3rd_identity)
1774 /* This target hook allows the backend to specify a calling convention
1775 in the debug information. This function actually returns an
1776 enum dwarf_calling_convention, but because of forward declarations
1777 and not wanting to include dwarf2.h everywhere target.h is included
1778 the function is being declared as an int. */
1779 DEFHOOK
1780 (dwarf_calling_convention,
1782 int, (const_tree function),
1783 hook_int_const_tree_0)
1785 /* This target hook allows the backend to emit frame-related insns that
1786 contain UNSPECs or UNSPEC_VOLATILEs. The call frame debugging info
1787 engine will invoke it on insns of the form
1788 (set (reg) (unspec [...] UNSPEC_INDEX))
1790 (set (reg) (unspec_volatile [...] UNSPECV_INDEX))
1791 to let the backend emit the call frame instructions. */
1792 DEFHOOK
1793 (dwarf_handle_frame_unspec,
1795 void, (const char *label, rtx pattern, int index), NULL)
1797 /* ??? Documenting this hook requires a GFDL license grant. */
1798 DEFHOOK_UNDOC
1799 (stdarg_optimize_hook,
1800 "Perform architecture specific checking of statements gimplified\
1801 from @code{VA_ARG_EXPR}. @var{stmt} is the statement. Returns true if\
1802 the statement doesn't need to be checked for @code{va_list} references.",
1803 bool, (struct stdarg_info *ai, const_gimple stmt), NULL)
1805 /* This target hook allows the operating system to override the DECL
1806 that represents the external variable that contains the stack
1807 protection guard variable. The type of this DECL is ptr_type_node. */
1808 DEFHOOK
1809 (stack_protect_guard,
1811 tree, (void),
1812 default_stack_protect_guard)
1814 /* This target hook allows the operating system to override the CALL_EXPR
1815 that is invoked when a check vs the guard variable fails. */
1816 DEFHOOK
1817 (stack_protect_fail,
1819 tree, (void),
1820 default_external_stack_protect_fail)
1822 DEFHOOK
1823 (supports_split_stack,
1824 "Whether this target supports splitting the stack when the options\
1825 described in @var{opts} have been passed. This is called\
1826 after options have been parsed, so the target may reject splitting\
1827 the stack in some configurations. The default version of this hook\
1828 returns false. If @var{report} is true, this function may issue a warning\
1829 or error; if @var{report} is false, it must simply return a value",
1830 bool, (bool report, struct gcc_options *opts),
1831 hook_bool_bool_gcc_optionsp_false)
1833 /* Returns NULL if target supports the insn within a doloop block,
1834 otherwise it returns an error message. */
1835 DEFHOOK
1836 (invalid_within_doloop,
1838 const char *, (const_rtx insn),
1839 default_invalid_within_doloop)
1841 DEFHOOK
1842 (valid_dllimport_attribute_p,
1843 "@var{decl} is a variable or function with @code{__attribute__((dllimport))}\
1844 specified. Use this hook if the target needs to add extra validation\
1845 checks to @code{handle_dll_attribute}.",
1846 bool, (const_tree decl),
1847 hook_bool_const_tree_true)
1849 /* If non-zero, align constant anchors in CSE to a multiple of this
1850 value. */
1851 DEFHOOKPOD
1852 (const_anchor,
1854 unsigned HOST_WIDE_INT, 0)
1856 /* Functions relating to calls - argument passing, returns, etc. */
1857 /* Members of struct call have no special macro prefix. */
1858 HOOK_VECTOR (TARGET_CALLS, calls)
1860 DEFHOOK
1861 (promote_function_mode,
1863 enum machine_mode, (const_tree type, enum machine_mode mode, int *punsignedp,
1864 const_tree funtype, int for_return),
1865 default_promote_function_mode)
1867 DEFHOOK
1868 (promote_prototypes,
1870 bool, (const_tree fntype),
1871 hook_bool_const_tree_false)
1873 DEFHOOK
1874 (struct_value_rtx,
1876 rtx, (tree fndecl, int incoming),
1877 hook_rtx_tree_int_null)
1878 DEFHOOK
1879 (return_in_memory,
1881 bool, (const_tree type, const_tree fntype),
1882 default_return_in_memory)
1884 DEFHOOK
1885 (return_in_msb,
1887 bool, (const_tree type),
1888 hook_bool_const_tree_false)
1890 /* Return true if a parameter must be passed by reference. TYPE may
1891 be null if this is a libcall. CA may be null if this query is
1892 from __builtin_va_arg. */
1893 DEFHOOK
1894 (pass_by_reference,
1896 bool,
1897 (CUMULATIVE_ARGS *cum, enum machine_mode mode, const_tree type, bool named),
1898 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false)
1900 DEFHOOK
1901 (expand_builtin_saveregs,
1903 rtx, (void),
1904 default_expand_builtin_saveregs)
1906 /* Returns pretend_argument_size. */
1907 DEFHOOK
1908 (setup_incoming_varargs,
1910 void, (CUMULATIVE_ARGS *args_so_far, enum machine_mode mode, tree type,
1911 int *pretend_args_size, int second_time),
1912 default_setup_incoming_varargs)
1914 DEFHOOK
1915 (strict_argument_naming,
1917 bool, (CUMULATIVE_ARGS *ca),
1918 hook_bool_CUMULATIVE_ARGS_false)
1920 /* Returns true if we should use
1921 targetm.calls.setup_incoming_varargs() and/or
1922 targetm.calls.strict_argument_naming(). */
1923 DEFHOOK
1924 (pretend_outgoing_varargs_named,
1926 bool, (CUMULATIVE_ARGS *ca),
1927 default_pretend_outgoing_varargs_named)
1929 /* Given a complex type T, return true if a parameter of type T
1930 should be passed as two scalars. */
1931 DEFHOOK
1932 (split_complex_arg,
1934 bool, (const_tree type), NULL)
1936 /* Return true if type T, mode MODE, may not be passed in registers,
1937 but must be passed on the stack. */
1938 /* ??? This predicate should be applied strictly after pass-by-reference.
1939 Need audit to verify that this is the case. */
1940 DEFHOOK
1941 (must_pass_in_stack,
1943 bool, (enum machine_mode mode, const_tree type),
1944 must_pass_in_stack_var_size_or_pad)
1946 /* Return true if type TYPE, mode MODE, which is passed by reference,
1947 should have the object copy generated by the callee rather than
1948 the caller. It is never called for TYPE requiring constructors. */
1949 DEFHOOK
1950 (callee_copies,
1952 bool,
1953 (CUMULATIVE_ARGS *cum, enum machine_mode mode, const_tree type, bool named),
1954 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false)
1956 /* Return zero for arguments passed entirely on the stack or entirely
1957 in registers. If passed in both, return the number of bytes passed
1958 in registers; the balance is therefore passed on the stack. */
1959 DEFHOOK
1960 (arg_partial_bytes,
1962 int, (CUMULATIVE_ARGS *cum, enum machine_mode mode, tree type, bool named),
1963 hook_int_CUMULATIVE_ARGS_mode_tree_bool_0)
1965 /* Update the state in CA to advance past an argument in the
1966 argument list. The values MODE, TYPE, and NAMED describe that
1967 argument. */
1968 DEFHOOK
1969 (function_arg_advance,
1971 void,
1972 (CUMULATIVE_ARGS *ca, enum machine_mode mode, const_tree type, bool named),
1973 default_function_arg_advance)
1975 /* Return zero if the argument described by the state of CA should
1976 be placed on a stack, or a hard register in which to store the
1977 argument. The values MODE, TYPE, and NAMED describe that
1978 argument. */
1979 DEFHOOK
1980 (function_arg,
1982 rtx, (CUMULATIVE_ARGS *ca, enum machine_mode mode, const_tree type,
1983 bool named),
1984 default_function_arg)
1986 /* Likewise, but for machines with register windows. Return the
1987 location where the argument will appear to the callee. */
1988 DEFHOOK
1989 (function_incoming_arg,
1991 rtx, (CUMULATIVE_ARGS *ca, enum machine_mode mode, const_tree type,
1992 bool named),
1993 default_function_incoming_arg)
1995 DEFHOOK
1996 (function_arg_boundary,
1998 unsigned int, (enum machine_mode mode, const_tree type),
1999 default_function_arg_boundary)
2001 /* Return the diagnostic message string if function without a prototype
2002 is not allowed for this 'val' argument; NULL otherwise. */
2003 DEFHOOK
2004 (invalid_arg_for_unprototyped_fn,
2006 const char *, (const_tree typelist, const_tree funcdecl, const_tree val),
2007 hook_invalid_arg_for_unprototyped_fn)
2009 /* Return an rtx for the return value location of the function
2010 specified by FN_DECL_OR_TYPE with a return type of RET_TYPE. */
2011 DEFHOOK
2012 (function_value,
2014 rtx, (const_tree ret_type, const_tree fn_decl_or_type, bool outgoing),
2015 default_function_value)
2017 /* Return the rtx for the result of a libcall of mode MODE,
2018 calling the function FN_NAME. */
2019 DEFHOOK
2020 (libcall_value,
2022 rtx, (enum machine_mode mode, const_rtx fun),
2023 default_libcall_value)
2025 /* Return true if REGNO is a possible register number for
2026 a function value as seen by the caller. */
2027 DEFHOOK
2028 (function_value_regno_p,
2030 bool, (const unsigned int regno),
2031 default_function_value_regno_p)
2033 /* ??? Documenting this hook requires a GFDL license grant. */
2034 DEFHOOK_UNDOC
2035 (internal_arg_pointer,
2036 "Return an rtx for the argument pointer incoming to the\
2037 current function.",
2038 rtx, (void),
2039 default_internal_arg_pointer)
2041 /* Update the current function stack boundary if needed. */
2042 DEFHOOK
2043 (update_stack_boundary,
2045 void, (void), NULL)
2047 /* Handle stack alignment and return an rtx for Dynamic Realign
2048 Argument Pointer if necessary. */
2049 DEFHOOK
2050 (get_drap_rtx,
2052 rtx, (void), NULL)
2054 /* Return true if all function parameters should be spilled to the
2055 stack. */
2056 DEFHOOK
2057 (allocate_stack_slots_for_args,
2059 bool, (void),
2060 hook_bool_void_true)
2062 /* Return an rtx for the static chain for FNDECL. If INCOMING_P is true,
2063 then it should be for the callee; otherwise for the caller. */
2064 DEFHOOK
2065 (static_chain,
2067 rtx, (const_tree fndecl, bool incoming_p),
2068 default_static_chain)
2070 /* Fill in the trampoline at MEM with a call to FNDECL and a
2071 static chain value of CHAIN. */
2072 DEFHOOK
2073 (trampoline_init,
2075 void, (rtx m_tramp, tree fndecl, rtx static_chain),
2076 default_trampoline_init)
2078 /* Adjust the address of the trampoline in a target-specific way. */
2079 DEFHOOK
2080 (trampoline_adjust_address,
2082 rtx, (rtx addr), NULL)
2084 /* Return the number of bytes of its own arguments that a function
2085 pops on returning, or 0 if the function pops no arguments and the
2086 caller must therefore pop them all after the function returns. */
2087 /* ??? tm.texi has no types for the parameters. */
2088 DEFHOOK
2089 (return_pops_args,
2091 int, (tree fundecl, tree funtype, int size),
2092 default_return_pops_args)
2094 /* Return a mode wide enough to copy any function value that might be
2095 returned. */
2096 DEFHOOK
2097 (get_raw_result_mode,
2098 "This target hook returns the mode to be used when accessing raw return\
2099 registers in @code{__builtin_return}. Define this macro if the value\
2100 in @var{reg_raw_mode} is not correct.",
2101 enum machine_mode, (int regno),
2102 default_get_reg_raw_mode)
2104 /* Return a mode wide enough to copy any argument value that might be
2105 passed. */
2106 DEFHOOK
2107 (get_raw_arg_mode,
2108 "This target hook returns the mode to be used when accessing raw argument\
2109 registers in @code{__builtin_apply_args}. Define this macro if the value\
2110 in @var{reg_raw_mode} is not correct.",
2111 enum machine_mode, (int regno),
2112 default_get_reg_raw_mode)
2114 HOOK_VECTOR_END (calls)
2116 /* Return the diagnostic message string if conversion from FROMTYPE
2117 to TOTYPE is not allowed, NULL otherwise. */
2118 DEFHOOK
2119 (invalid_conversion,
2121 const char *, (const_tree fromtype, const_tree totype),
2122 hook_constcharptr_const_tree_const_tree_null)
2124 /* Return the diagnostic message string if the unary operation OP is
2125 not permitted on TYPE, NULL otherwise. */
2126 DEFHOOK
2127 (invalid_unary_op,
2129 const char *, (int op, const_tree type),
2130 hook_constcharptr_int_const_tree_null)
2132 /* Return the diagnostic message string if the binary operation OP
2133 is not permitted on TYPE1 and TYPE2, NULL otherwise. */
2134 DEFHOOK
2135 (invalid_binary_op,
2137 const char *, (int op, const_tree type1, const_tree type2),
2138 hook_constcharptr_int_const_tree_const_tree_null)
2140 /* Return the diagnostic message string if TYPE is not valid as a
2141 function parameter type, NULL otherwise. */
2142 DEFHOOK
2143 (invalid_parameter_type,
2145 const char *, (const_tree type),
2146 hook_constcharptr_const_tree_null)
2148 /* Return the diagnostic message string if TYPE is not valid as a
2149 function return type, NULL otherwise. */
2150 DEFHOOK
2151 (invalid_return_type,
2153 const char *, (const_tree type),
2154 hook_constcharptr_const_tree_null)
2156 /* If values of TYPE are promoted to some other type when used in
2157 expressions (analogous to the integer promotions), return that type,
2158 or NULL_TREE otherwise. */
2159 DEFHOOK
2160 (promoted_type,
2162 tree, (const_tree type),
2163 hook_tree_const_tree_null)
2165 /* Convert EXPR to TYPE, if target-specific types with special conversion
2166 rules are involved. Return the converted expression, or NULL to apply
2167 the standard conversion rules. */
2168 DEFHOOK
2169 (convert_to_type,
2171 tree, (tree type, tree expr),
2172 hook_tree_tree_tree_null)
2174 /* Return the class for a secondary reload, and fill in extra information. */
2175 DEFHOOK
2176 (secondary_reload,
2178 reg_class_t,
2179 (bool in_p, rtx x, reg_class_t reload_class, enum machine_mode reload_mode,
2180 secondary_reload_info *sri),
2181 default_secondary_reload)
2183 /* Given an rtx X being reloaded into a reg required to be in class CLASS,
2184 return the class of reg to actually use. */
2185 DEFHOOK
2186 (preferred_reload_class,
2188 reg_class_t,
2189 (rtx x, reg_class_t rclass),
2190 default_preferred_reload_class)
2192 /* Like TARGET_PREFERRED_RELOAD_CLASS, but for output reloads instead of
2193 input reloads. */
2194 DEFHOOK
2195 (preferred_output_reload_class,
2197 reg_class_t,
2198 (rtx x, reg_class_t rclass),
2199 default_preferred_output_reload_class)
2201 DEFHOOK
2202 (class_likely_spilled_p,
2204 bool, (reg_class_t rclass),
2205 default_class_likely_spilled_p)
2207 DEFHOOK
2208 (preferred_rename_class,
2209 "A target hook that places additional preference on the register\
2210 class to use when it is necessary to rename a register in class\
2211 @var{rclass} to another class, or perhaps @var{NO_REGS}, if no\
2212 preferred register class is found or hook @code{preferred_rename_class}\
2213 is not implemented.\
2214 Sometimes returning a more restrictive class makes better code. For\
2215 example, on ARM, thumb-2 instructions using @code{LO_REGS} may be\
2216 smaller than instructions using @code{GENERIC_REGS}. By returning\
2217 @code{LO_REGS} from @code{preferred_rename_class}, code size can\
2218 be reduced.",
2219 reg_class_t, (reg_class_t rclass),
2220 default_preferred_rename_class)
2222 /* This target hook allows the backend to perform additional
2223 processing while initializing for variable expansion. */
2224 DEFHOOK
2225 (expand_to_rtl_hook,
2227 void, (void),
2228 hook_void_void)
2230 /* This target hook allows the backend to perform additional
2231 instantiations on rtx that are not actually in insns yet,
2232 but will be later. */
2233 DEFHOOK
2234 (instantiate_decls,
2236 void, (void),
2237 hook_void_void)
2239 /* Return true if is OK to use a hard register REGNO as scratch register
2240 in peephole2. */
2241 DEFHOOK
2242 (hard_regno_scratch_ok,
2244 bool, (unsigned int regno),
2245 default_hard_regno_scratch_ok)
2247 /* Return the smallest number of different values for which it is best to
2248 use a jump-table instead of a tree of conditional branches. */
2249 DEFHOOK
2250 (case_values_threshold,
2252 unsigned int, (void),
2253 default_case_values_threshold)
2255 /* Retutn true if a function must have and use a frame pointer. */
2256 DEFHOOK
2257 (frame_pointer_required,
2259 bool, (void),
2260 hook_bool_void_false)
2262 /* Returns true if the compiler is allowed to try to replace register number
2263 from-reg with register number to-reg. */
2264 DEFHOOK
2265 (can_eliminate,
2267 bool, (const int from_reg, const int to_reg),
2268 hook_bool_const_int_const_int_true)
2270 /* Modify any or all of fixed_regs, call_used_regs, global_regs,
2271 reg_names, and reg_class_contents to account of the vagaries of the
2272 target. */
2273 DEFHOOK
2274 (conditional_register_usage,
2276 void, (void),
2277 hook_void_void)
2279 /* Functions specific to the C family of frontends. */
2280 #undef HOOK_PREFIX
2281 #define HOOK_PREFIX "TARGET_C_"
2282 HOOK_VECTOR (TARGET_C, c)
2284 /* ??? Documenting this hook requires a GFDL license grant. */
2285 DEFHOOK_UNDOC
2286 (mode_for_suffix,
2287 "Return machine mode for non-standard constant literal suffix @var{c},\
2288 or VOIDmode if non-standard suffixes are unsupported.",
2289 enum machine_mode, (char c),
2290 default_mode_for_suffix)
2292 HOOK_VECTOR_END (c)
2294 /* Functions specific to the C++ frontend. */
2295 #undef HOOK_PREFIX
2296 #define HOOK_PREFIX "TARGET_CXX_"
2297 HOOK_VECTOR (TARGET_CXX, cxx)
2299 /* Return the integer type used for guard variables. */
2300 DEFHOOK
2301 (guard_type,
2303 tree, (void),
2304 default_cxx_guard_type)
2306 /* Return true if only the low bit of the guard should be tested. */
2307 DEFHOOK
2308 (guard_mask_bit,
2310 bool, (void),
2311 hook_bool_void_false)
2313 /* Returns the size of the array cookie for an array of type. */
2314 DEFHOOK
2315 (get_cookie_size,
2317 tree, (tree type),
2318 default_cxx_get_cookie_size)
2320 /* Returns true if the element size should be stored in the array cookie. */
2321 DEFHOOK
2322 (cookie_has_size,
2324 bool, (void),
2325 hook_bool_void_false)
2327 /* Allows backends to perform additional processing when
2328 deciding if a class should be exported or imported. */
2329 DEFHOOK
2330 (import_export_class,
2332 int, (tree type, int import_export), NULL)
2334 /* Returns true if constructors and destructors return "this". */
2335 DEFHOOK
2336 (cdtor_returns_this,
2338 bool, (void),
2339 hook_bool_void_false)
2341 /* Returns true if the key method for a class can be an inline
2342 function, so long as it is not declared inline in the class
2343 itself. Returning true is the behavior required by the Itanium C++ ABI. */
2344 DEFHOOK
2345 (key_method_may_be_inline,
2347 bool, (void),
2348 hook_bool_void_true)
2350 DEFHOOK
2351 (determine_class_data_visibility,
2352 "@var{decl} is a virtual table, virtual table table, typeinfo object,\
2353 or other similar implicit class data object that will be emitted with\
2354 external linkage in this translation unit. No ELF visibility has been\
2355 explicitly specified. If the target needs to specify a visibility\
2356 other than that of the containing class, use this hook to set\
2357 @code{DECL_VISIBILITY} and @code{DECL_VISIBILITY_SPECIFIED}.",
2358 void, (tree decl),
2359 hook_void_tree)
2361 /* Returns true (the default) if virtual tables and other
2362 similar implicit class data objects are always COMDAT if they
2363 have external linkage. If this hook returns false, then
2364 class data for classes whose virtual table will be emitted in
2365 only one translation unit will not be COMDAT. */
2366 DEFHOOK
2367 (class_data_always_comdat,
2369 bool, (void),
2370 hook_bool_void_true)
2372 /* Returns true (the default) if the RTTI for the basic types,
2373 which is always defined in the C++ runtime, should be COMDAT;
2374 false if it should not be COMDAT. */
2375 DEFHOOK
2376 (library_rtti_comdat,
2378 bool, (void),
2379 hook_bool_void_true)
2381 /* Returns true if __aeabi_atexit should be used to register static
2382 destructors. */
2383 DEFHOOK
2384 (use_aeabi_atexit,
2386 bool, (void),
2387 hook_bool_void_false)
2389 /* Returns true if target may use atexit in the same manner as
2390 __cxa_atexit to register static destructors. */
2391 DEFHOOK
2392 (use_atexit_for_cxa_atexit,
2394 bool, (void),
2395 hook_bool_void_false)
2397 DEFHOOK
2398 (adjust_class_at_definition,
2399 "@var{type} is a C++ class (i.e., RECORD_TYPE or UNION_TYPE) that has just\
2400 been defined. Use this hook to make adjustments to the class (eg, tweak\
2401 visibility or perform any other required target modifications).",
2402 void, (tree type),
2403 hook_void_tree)
2405 HOOK_VECTOR_END (cxx)
2407 /* Functions and data for emulated TLS support. */
2408 #undef HOOK_PREFIX
2409 #define HOOK_PREFIX "TARGET_EMUTLS_"
2410 HOOK_VECTOR (TARGET_EMUTLS, emutls)
2412 /* Name of the address and common functions. */
2413 DEFHOOKPOD
2414 (get_address,
2416 const char *, "__builtin___emutls_get_address")
2418 DEFHOOKPOD
2419 (register_common,
2421 const char *, "__builtin___emutls_register_common")
2423 /* Prefixes for proxy variable and template. */
2424 DEFHOOKPOD
2425 (var_section,
2427 const char *, NULL)
2429 DEFHOOKPOD
2430 (tmpl_section,
2432 const char *, NULL)
2434 /* Prefixes for proxy variable and template. */
2435 DEFHOOKPOD
2436 (var_prefix,
2438 const char *, NULL)
2440 DEFHOOKPOD
2441 (tmpl_prefix,
2443 const char *, NULL)
2445 /* Function to generate field definitions of the proxy variable. */
2446 DEFHOOK
2447 (var_fields,
2449 tree, (tree type, tree *name),
2450 default_emutls_var_fields)
2452 /* Function to initialize a proxy variable. */
2453 DEFHOOK
2454 (var_init,
2456 tree, (tree var, tree decl, tree tmpl_addr),
2457 default_emutls_var_init)
2459 /* Whether we are allowed to alter the usual alignment of the
2460 proxy variable. */
2461 DEFHOOKPOD
2462 (var_align_fixed,
2464 bool, false)
2466 /* Whether we can emit debug information for TLS vars. */
2467 DEFHOOKPOD
2468 (debug_form_tls_address,
2470 bool, false)
2472 HOOK_VECTOR_END (emutls)
2474 #undef HOOK_PREFIX
2475 #define HOOK_PREFIX "TARGET_OPTION_"
2476 HOOK_VECTOR (TARGET_OPTION_HOOKS, target_option_hooks)
2478 /* Function to validate the attribute((option(...))) strings or NULL. If
2479 the option is validated, it is assumed that DECL_FUNCTION_SPECIFIC will
2480 be filled in in the function decl node. */
2481 DEFHOOK
2482 (valid_attribute_p,
2484 bool, (tree fndecl, tree name, tree args, int flags),
2485 default_target_option_valid_attribute_p)
2487 /* Function to save any extra target state in the target options structure. */
2488 DEFHOOK
2489 (save,
2491 void, (struct cl_target_option *ptr), NULL)
2493 /* Function to restore any extra target state from the target options
2494 structure. */
2495 DEFHOOK
2496 (restore,
2498 void, (struct cl_target_option *ptr), NULL)
2500 /* Function to print any extra target state from the target options
2501 structure. */
2502 DEFHOOK
2503 (print,
2505 void, (FILE *file, int indent, struct cl_target_option *ptr), NULL)
2507 /* Function to parse arguments to be validated for #pragma option, and to
2508 change the state if the options are valid. If the first argument is
2509 NULL, the second argument specifies the default options to use. Return
2510 true if the options are valid, and set the current state. */
2511 /* ??? The documentation in tm.texi is incomplete. */
2512 DEFHOOK
2513 (pragma_parse,
2515 bool, (tree args, tree pop_target),
2516 default_target_option_pragma_parse)
2518 /* Do option overrides for the target. */
2519 DEFHOOK
2520 (override,
2522 void, (void),
2523 hook_void_void)
2525 /* Set default optimizations for the target. */
2526 DEFHOOKPOD
2527 (optimization_table,
2529 const struct default_options *, empty_optimization_table)
2531 DEFHOOK
2532 (default_params,
2533 "Set target-dependent default values for @option{--param} settings, using\
2534 calls to @code{set_default_param_value}.",
2535 void, (void),
2536 hook_void_void)
2538 DEFHOOK
2539 (init_struct,
2540 "Set target-dependent initial values of fields in @var{opts}.",
2541 void, (struct gcc_options *opts),
2542 hook_void_gcc_optionsp)
2544 /* Function to determine if one function can inline another function. */
2545 #undef HOOK_PREFIX
2546 #define HOOK_PREFIX "TARGET_"
2547 DEFHOOK
2548 (can_inline_p,
2550 bool, (tree caller, tree callee),
2551 default_target_can_inline_p)
2553 HOOK_VECTOR_END (target_option)
2555 /* For targets that need to mark extra registers as live on entry to
2556 the function, they should define this target hook and set their
2557 bits in the bitmap passed in. */
2558 DEFHOOK
2559 (extra_live_on_entry,
2561 void, (bitmap regs),
2562 hook_void_bitmap)
2564 /* Determine the type of unwind info to emit for debugging. */
2565 DEFHOOK
2566 (debug_unwind_info,
2568 enum unwind_info_type, (void),
2569 default_debug_unwind_info)
2571 /* Determine the type of unwind info to emit for exceptions. */
2572 DEFHOOK
2573 (except_unwind_info,
2575 enum unwind_info_type, (struct gcc_options *opts),
2576 default_except_unwind_info)
2578 /* Leave the boolean fields at the end. */
2580 /* True if unwinding tables should be generated by default. */
2581 DEFHOOKPOD
2582 (unwind_tables_default,
2584 bool, false)
2586 /* True if arbitrary sections are supported. */
2587 DEFHOOKPOD
2588 (have_named_sections,
2590 bool, false)
2592 /* True if we can create zeroed data by switching to a BSS section
2593 and then using ASM_OUTPUT_SKIP to allocate the space. */
2594 DEFHOOKPOD
2595 (have_switchable_bss_sections,
2597 bool, false)
2599 /* True if "native" constructors and destructors are supported,
2600 false if we're using collect2 for the job. */
2601 DEFHOOKPOD
2602 (have_ctors_dtors,
2604 bool, false)
2606 /* True if thread-local storage is supported. */
2607 DEFHOOKPOD
2608 (have_tls,
2610 bool, false)
2612 /* True if a small readonly data section is supported. */
2613 DEFHOOKPOD
2614 (have_srodata_section,
2616 bool, false)
2618 /* True if EH frame info sections should be zero-terminated. */
2619 DEFHOOKPOD
2620 (terminate_dw2_eh_frame_info,
2622 bool, true)
2624 /* True if #NO_APP should be emitted at the beginning of assembly output. */
2625 DEFHOOKPOD
2626 (asm_file_start_app_off,
2628 bool, false)
2630 /* True if output_file_directive should be called for main_input_filename
2631 at the beginning of assembly output. */
2632 DEFHOOKPOD
2633 (asm_file_start_file_directive,
2635 bool, false)
2637 DEFHOOKPOD
2638 (handle_pragma_extern_prefix,
2639 "True if @code{#pragma extern_prefix} is to be supported.",
2640 bool, 0)
2642 /* True if the target is allowed to reorder memory accesses unless
2643 synchronization is explicitly requested. */
2644 DEFHOOKPOD
2645 (relaxed_ordering,
2647 bool, false)
2649 /* Returns true if we should generate exception tables for use with the
2650 ARM EABI. The effects the encoding of function exception specifications. */
2651 DEFHOOKPOD
2652 (arm_eabi_unwinder,
2654 bool, false)
2656 DEFHOOKPOD
2657 (want_debug_pub_sections,
2658 "True if the @code{.debug_pubtypes} and @code{.debug_pubnames} sections\
2659 should be emitted. These sections are not used on most platforms, and\
2660 in particular GDB does not use them.",
2661 bool, false)
2663 /* Leave the boolean fields at the end. */
2665 /* Close the 'struct gcc_target' definition. */
2666 HOOK_VECTOR_END (C90_EMPTY_HACK)