1 /* Target hook definitions.
2 Copyright (C
) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
3 Free Software Foundation
, Inc.
5 This program is free software
; you can redistribute it and
/or modify it
6 under the terms of the GNU General Public License as published by the
7 Free Software Foundation
; either version
3, or (at your option
) any
10 This program is distributed in the hope that it will be useful
,
11 but WITHOUT ANY WARRANTY
; without even the implied warranty of
12 MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program
; see the file COPYING3. If not see
17 <http
://www.gnu.org
/licenses
/>.
19 In other words
, you are welcome to use
, share and improve this program.
20 You are forbidden to forbid anyone else to use
, share and improve
21 what you give them. Help stamp out software
-hoarding
! */
23 /* The following macros should be provided by the including file
:
25 DEFHOOK(NAME
, DOC
, TYPE, PARAMS
, INIT
): Define a function
-valued hook.
26 DEFHOOKPOD(DOC
, TYPE, NAME
, INIT
): Define a piece
-of
-data
'hook'.
*/
28 /* Defaults for optional macros
:
29 DEFHOOKPODX(NAME
, TYPE, INIT
): Like DEFHOOKPOD
, but share documentation
30 with the previous
'hook'.
*/
32 #define
DEFHOOKPODX(NAME
, TYPE, INIT
) DEFHOOKPOD (NAME
, 0, TYPE, INIT
)
35 /* HOOKSTRUCT(FRAGMENT
): Declarator fragments to encapsulate all the
36 members into a struct gcc_target
, which in turn contains several
39 #define
HOOKSTRUCT(FRAGMENT
)
41 /* HOOK_VECTOR
: Start a struct declaration
, which then gets its own initializer.
42 HOOK_VECTOR_END
: Close a struct declaration
, providing a member declarator
43 name for nested use.
*/
45 #define
HOOK_VECTOR_1(NAME
, FRAGMENT
) HOOKSTRUCT(FRAGMENT
)
47 #define
HOOK_VECTOR(INIT_NAME
, SNAME
) HOOK_VECTOR_1 (INIT_NAME
, struct SNAME
{)
48 #define
HOOK_VECTOR_END(DECL_NAME
) HOOK_VECTOR_1(,} DECL_NAME
;)
50 HOOK_VECTOR (TARGET_INITIALIZER
, gcc_target
)
52 /* FIXME
: For pre
-existing hooks
, we can
't place the documentation in the
53 documentation field here till we get permission from the FSF to include
54 it in GPLed software - the target hook documentation is so far only
55 available under the GFDL. */
57 /* A hook should generally be documented by a string in the DOC parameter,
58 which should contain texinfo markup. If the documentation is only available
59 under the GPL, but not under the GFDL, put it in a comment above the hook
60 definition. If the function declaration is available both under GPL and
61 GFDL, but the documentation is only available under the GFDL, put the
62 documentaton in tm.texi.in, heading with @hook <hookname> and closing
63 the paragraph with @end deftypefn / deftypevr as appropriate, and marking
64 the next autogenerated hook with @hook <hookname>.
65 In both these cases, leave the DOC string empty, i.e. "".
66 Sometimes, for some historic reason the function declaration
67 has to be documented differently
68 than what it is. In that case, use DEFHOOK_UNDOC to supress auto-generation
69 of documentation. DEFHOOK_UNDOC takes a DOC string which it ignores, so
70 you can put GPLed documentation string there if you have hopes that you
71 can clear the declaration & documentation for GFDL distribution later,
72 in which case you can then simply change the DEFHOOK_UNDOC to DEFHOOK
73 to turn on the autogeneration of the documentation.
75 A documentation string of "*" means not to emit any documentation at all,
76 and is mainly used internally for DEFHOOK_UNDOC. It should generally not
77 be used otherwise, but it has its use for exceptional cases where automatic
78 documentation is not wanted, and the real documentation is elsewere, like
79 for TARGET_ASM_{,UN}ALIGNED_INT_OP, which are hooks only for implementation
80 purposes; they refer to structs, the components of which are documented as
81 separate hooks TARGET_ASM_{,UN}ALIGNED_[HSDT]I_OP.
82 A DOC string of 0 is for internal use of DEFHOOKPODX and special table
85 /* Functions that output assembler for the target. */
86 #define HOOK_PREFIX "TARGET_ASM_"
87 HOOK_VECTOR (TARGET_ASM_OUT, asm_out)
89 /* Opening and closing parentheses for asm expression grouping. */
94 DEFHOOKPODX (close_paren, const char *, ")")
96 /* Assembler instructions for creating various kinds of integer object. */
100 const char *, "\t.byte\t")
101 DEFHOOKPOD (aligned_op, "*", struct asm_int_op, TARGET_ASM_ALIGNED_INT_OP)
102 DEFHOOKPOD (unaligned_op, "*", struct asm_int_op, TARGET_ASM_UNALIGNED_INT_OP)
104 /* Try to output the assembler code for an integer object whose
105 value is given by X. SIZE is the size of the object in bytes and
106 ALIGNED_P indicates whether it is aligned. Return true if
107 successful. Only handles cases for which BYTE_OP, ALIGNED_OP
108 and UNALIGNED_OP are NULL. */
112 /* Only handles cases for which BYTE_OP, ALIGNED_OP and UNALIGNED_OP are
114 bool, (rtx x, unsigned int size, int aligned_p),
115 default_assemble_integer)
117 /* Output code that will globalize a label. */
121 void, (FILE *stream, const char *name),
122 default_globalize_label)
124 /* Output code that will globalize a declaration. */
126 (globalize_decl_name,
128 void, (FILE *stream, tree decl), default_globalize_decl_name)
130 /* Output code that will emit a label for unwind info, if this
131 target requires such labels. Second argument is the decl the
132 unwind info is associated with, third is a boolean: true if
133 this is for exception handling, fourth is a boolean: true if
134 this is only a placeholder for an omitted FDE. */
138 void, (FILE *stream, tree decl, int for_eh, int empty),
139 default_emit_unwind_label)
141 /* Output code that will emit a label to divide up the exception table. */
143 (emit_except_table_label,
145 void, (FILE *stream),
146 default_emit_except_table_label)
148 /* Emit any directives required to unwind this instruction. */
152 void, (FILE *stream, rtx insn),
155 /* Output an internal label. */
159 void, (FILE *stream, const char *prefix, unsigned long labelno),
160 default_internal_label)
162 /* Output label for the constant. */
164 (declare_constant_name,
166 void, (FILE *file, const char *name, const_tree expr, HOST_WIDE_INT size),
167 default_asm_declare_constant_name)
169 /* Emit a ttype table reference to a typeinfo object. */
176 /* Emit an assembler directive to set visibility for the symbol
177 associated with the tree decl. */
179 (assemble_visibility,
181 void, (tree decl, int visibility),
182 default_assemble_visibility)
184 /* Output the assembler code for entry to a function. */
188 void, (FILE *file, HOST_WIDE_INT size),
189 default_function_pro_epilogue)
191 /* Output the assembler code for end of prologue. */
193 (function_end_prologue,
198 /* Output the assembler code for start of epilogue. */
200 (function_begin_epilogue,
205 /* Output the assembler code for function exit. */
209 void, (FILE *file, HOST_WIDE_INT size),
210 default_function_pro_epilogue)
212 /* Initialize target-specific sections. */
219 /* Tell assembler to change to section NAME with attributes FLAGS.
220 If DECL is non-NULL, it is the VAR_DECL or FUNCTION_DECL with
221 which this section is associated. */
225 void, (const char *name, unsigned int flags, tree decl),
226 default_no_named_section)
228 /* Return a mask describing how relocations should be treated when
229 selecting sections. Bit 1 should be set if global relocations
230 should be placed in a read-write section; bit 0 should be set if
231 local relocations should be placed in a read-write section. */
236 default_reloc_rw_mask)
238 /* Return a section for EXP. It may be a DECL or a constant. RELOC
239 is nonzero if runtime relocations must be applied; bit 1 will be
240 set if the runtime relocations require non-local name resolution.
241 ALIGN is the required alignment of the data. */
245 section *, (tree exp, int reloc, unsigned HOST_WIDE_INT align),
246 default_select_section)
248 /* Return a section for X. MODE is X's mode and ALIGN is its
249 alignment in bits.
*/
253 section
*, (enum machine_mode mode
, rtx x
, unsigned HOST_WIDE_INT align
),
254 default_select_rtx_section
)
256 /* Select a unique section name for DECL. RELOC is the same as
257 for SELECT_SECTION.
*/
261 void
, (tree decl
, int reloc
),
262 default_unique_section
)
264 /* Return the readonly data section associated with function DECL.
*/
266 (function_rodata_section
,
268 section
*, (tree decl
),
269 default_function_rodata_section
)
271 /* Output a constructor for a symbol with a given priority.
*/
275 void
, (rtx symbol
, int priority
), NULL
)
277 /* Output a destructor for a symbol with a given priority.
*/
281 void
, (rtx symbol
, int priority
), NULL
)
283 /* Output the assembler code for a thunk function. THUNK_DECL is the
284 declaration for the thunk function itself
, FUNCTION is the decl for
285 the target function. DELTA is an immediate constant offset to be
286 added to THIS. If VCALL_OFFSET is nonzero
, the word at
287 *(*this + vcall_offset) should be added to THIS. */
291 void, (FILE *file, tree thunk_fndecl, HOST_WIDE_INT delta,
292 HOST_WIDE_INT vcall_offset, tree function),
295 /* Determine whether output_mi_thunk would succeed. */
296 /* ??? Ideally, this hook would not exist, and success or failure
297 would be returned from output_mi_thunk directly. But there's
298 too much undo-able setup involved in invoking output_mi_thunk.
299 Could be fixed by making output_mi_thunk emit rtl instead of
300 text to the output file. */
302 (can_output_mi_thunk,
304 bool, (const_tree thunk_fndecl, HOST_WIDE_INT delta,
305 HOST_WIDE_INT vcall_offset, const_tree function),
306 hook_bool_const_tree_hwi_hwi_const_tree_false)
308 /* Output any boilerplate text needed at the beginning of a
316 /* Output any boilerplate text needed at the end of a translation unit. */
323 /* Output any boilerplate text needed at the beginning of an
324 LTO output stream. */
331 /* Output any boilerplate text needed at the end of an
332 LTO output stream. */
339 /* Output any boilerplace text needed at the end of a
340 translation unit before debug and unwind info is emitted. */
347 /* Output an assembler pseudo-op to declare a library function name
353 default_external_libcall)
355 /* Output an assembler directive to mark decl live. This instructs
356 linker to not dead code strip this symbol. */
358 (mark_decl_preserved,
360 void, (const char *symbol),
361 hook_void_constcharptr)
363 /* Output a record of the command line switches that have been passed. */
365 (record_gcc_switches,
367 int, (print_switch_type type, const char *text),
370 /* The name of the section that the example ELF implementation of
371 record_gcc_switches will use to store the information. Target
372 specific versions of record_gcc_switches may or may not use
375 (record_gcc_switches_section,
377 const char *, ".GCC.command.line")
379 /* Output the definition of a section anchor. */
384 default_asm_output_anchor)
386 /* Output a DTP-relative reference to a TLS symbol. */
388 (output_dwarf_dtprel,
390 void, (FILE *file, int size, rtx x),
393 /* Some target machines need to postscan each insn after it is output. */
395 (final_postscan_insn,
397 void, (FILE *file, rtx insn, rtx *opvec, int noperands),
400 /* Emit the trampoline template. This hook may be NULL. */
402 (trampoline_template,
407 /* ??? The TARGET_PRINT_OPERAND* hooks are part of the asm_out struct,
408 even though that is not reflected in the macro name to override their
411 #define HOOK_PREFIX "TARGET_"
413 /* Emit a machine-specific insn operand. */
414 /* ??? tm.texi only documents the old macro PRINT_OPERAND,
415 not this hook, and uses a different name for the argument FILE. */
419 void, (FILE *file, rtx x, int code),
420 default_print_operand)
422 /* Emit a machine-specific memory address. */
423 /* ??? tm.texi only documents the old macro PRINT_OPERAND_ADDRESS,
424 not this hook, and uses different argument names. */
426 (print_operand_address,
428 void, (FILE *file, rtx addr),
429 default_print_operand_address)
431 /* Determine whether CODE is a valid punctuation character for the
432 `print_operand' hook. */
433 /* ??? tm.texi only documents the old macro PRINT_OPERAND_PUNCT_VALID_P,
436 (print_operand_punct_valid_p,
438 bool ,(unsigned char code),
439 default_print_operand_punct_valid_p)
441 HOOK_VECTOR_END (asm_out)
443 /* Functions relating to instruction scheduling. All of these
444 default to null pointers, which haifa-sched.c looks for and handles. */
446 #define HOOK_PREFIX "TARGET_SCHED_"
447 HOOK_VECTOR (TARGET_SCHED, sched)
449 /* Given the current cost, COST, of an insn, INSN, calculate and
450 return a new cost based on its relationship to DEP_INSN through
451 the dependence LINK. The default is to make no adjustment. */
455 int, (rtx insn, rtx link, rtx dep_insn, int cost), NULL)
457 /* Adjust the priority of an insn as you see fit. Returns the new priority. */
461 int, (rtx insn, int priority), NULL)
463 /* Function which returns the maximum number of insns that can be
464 scheduled in the same machine cycle. This must be constant
465 over an entire compilation. The default is 1. */
471 /* Calculate how much this insn affects how many more insns we
472 can emit this cycle. Default is they all cost the same. */
476 int, (FILE *file, int verbose, rtx insn, int more), NULL)
478 /* Initialize machine-dependent scheduling code. */
482 void, (FILE *file, int verbose, int max_ready), NULL)
484 /* Finalize machine-dependent scheduling code. */
488 void, (FILE *file, int verbose), NULL)
490 /* Initialize machine-dependent function wide scheduling code. */
494 void, (FILE *file, int verbose, int old_max_uid), NULL)
496 /* Finalize machine-dependent function wide scheduling code. */
500 void, (FILE *file, int verbose), NULL)
502 /* Reorder insns in a machine-dependent fashion, in two different
503 places. Default does nothing. */
507 int, (FILE *file, int verbose, rtx *ready, int *n_readyp, int clock), NULL)
512 int, (FILE *file, int verbose, rtx *ready, int *n_readyp, int clock), NULL)
514 /* The following member value is a pointer to a function called
515 after evaluation forward dependencies of insns in chain given
516 by two parameter values (head and tail correspondingly). */
518 (dependencies_evaluation_hook,
520 void, (rtx head, rtx tail), NULL)
522 /* The values of the following four members are pointers to functions
523 used to simplify the automaton descriptions. dfa_pre_cycle_insn and
524 dfa_post_cycle_insn give functions returning insns which are used to
525 change the pipeline hazard recognizer state when the new simulated
526 processor cycle correspondingly starts and finishes. The function
527 defined by init_dfa_pre_cycle_insn and init_dfa_post_cycle_insn are
528 used to initialize the corresponding insns. The default values of
529 the members result in not changing the automaton state when the
530 new simulated processor cycle correspondingly starts and finishes. */
533 (init_dfa_pre_cycle_insn,
543 (init_dfa_post_cycle_insn,
548 (dfa_post_cycle_insn,
552 /* The values of the following two members are pointers to
553 functions used to simplify the automaton descriptions.
554 dfa_pre_advance_cycle and dfa_post_advance_cycle are getting called
555 immediately before and after cycle is advanced. */
558 (dfa_pre_advance_cycle,
563 (dfa_post_advance_cycle,
567 /* The following member value is a pointer to a function returning value
568 which defines how many insns in queue `ready' will we try for
569 multi-pass scheduling. If the member value is nonzero and the
570 function returns positive value, the DFA based scheduler will make
571 multi-pass scheduling for the first cycle. In other words, we will
572 try to choose ready insn which permits to start maximum number of
573 insns on the same cycle. */
575 (first_cycle_multipass_dfa_lookahead,
579 /* The following member value is pointer to a function controlling
580 what insns from the ready insn queue will be considered for the
581 multipass insn scheduling. If the hook returns zero for insn
582 passed as the parameter, the insn will be not chosen to be issued. */
584 (first_cycle_multipass_dfa_lookahead_guard,
586 int, (rtx insn), NULL)
588 /* The following member value is pointer to a function called by
589 the insn scheduler before issuing insn passed as the third
590 parameter on given cycle. If the hook returns nonzero, the
591 insn is not issued on given processors cycle. Instead of that,
592 the processor cycle is advanced. If the value passed through
593 the last parameter is zero, the insn ready queue is not sorted
594 on the new cycle start as usually. The first parameter passes
595 file for debugging output. The second one passes the scheduler
596 verbose level of the debugging output. The forth and the fifth
597 parameter values are correspondingly processor cycle on which
598 the previous insn has been issued and the current processor cycle. */
602 int, (FILE *dump, int verbose, rtx insn, int last_clock,
603 int clock, int *sort_p),
606 /* The following member value is a pointer to a function called by the
607 insn scheduler. It should return true if there exists a dependence
608 which is considered costly by the target, between the insn
609 DEP_PRO (&_DEP), and the insn DEP_CON (&_DEP). The first parameter is
610 the dep that represents the dependence between the two insns. The
611 second argument is the cost of the dependence as estimated by
612 the scheduler. The last argument is the distance in cycles
613 between the already scheduled insn (first parameter) and the
614 second insn (second parameter). */
616 (is_costly_dependence,
618 bool, (struct _dep *_dep, int cost, int distance), NULL)
622 "Given the current cost, @var{cost}, of an insn, @var{insn}, calculate and\
623 return a new cost based on its relationship to @var{dep_insn} through the\
624 dependence of weakness @var{dw}. The default is to make no adjustment.",
625 int, (rtx insn, int dep_type1, rtx dep_insn, int cost, int dw), NULL)
627 /* The following member value is a pointer to a function called
628 by the insn scheduler. This hook is called to notify the backend
629 that new instructions were emitted. */
635 /* Next 5 functions are for multi-point scheduling. */
637 /* Allocate memory for scheduler context. */
639 (alloc_sched_context,
641 void *, (void), NULL)
643 /* Fills the context from the local machine scheduler context. */
647 void, (void *tc, bool clean_p), NULL)
649 /* Sets local machine scheduler context to a saved value. */
653 void, (void *tc), NULL)
655 /* Clears a scheduler context so it becomes like after init. */
657 (clear_sched_context,
659 void, (void *tc), NULL)
661 /* Frees the scheduler context. */
665 void, (void *tc), NULL)
667 /* The following member value is a pointer to a function called
668 by the insn scheduler.
669 The first parameter is an instruction, the second parameter is the type
670 of the requested speculation, and the third parameter is a pointer to the
671 speculative pattern of the corresponding type (set if return value == 1).
673 -1, if there is no pattern, that will satisfy the requested speculation type,
674 0, if current pattern satisfies the requested speculation type,
675 1, if pattern of the instruction should be changed to the newly
680 int, (rtx insn, int request, rtx *new_pat), NULL)
682 /* The following member value is a pointer to a function called
683 by the insn scheduler. It should return true if the check instruction
684 passed as the parameter needs a recovery block. */
688 bool, (int dep_status), NULL)
690 /* The following member value is a pointer to a function called
691 by the insn scheduler. It should return a pattern for the check
693 The first parameter is a speculative instruction, the second parameter
694 is the label of the corresponding recovery block (or null, if it is a
695 simple check). If the mutation of the check is requested (e.g. from
696 ld.c to chk.a), the third parameter is true - in this case the first
697 parameter is the previous check. */
701 rtx, (rtx insn, rtx label, int mutate_p), NULL)
703 /* The following member value is a pointer to a function controlling
704 what insns from the ready insn queue will be considered for the
705 multipass insn scheduling. If the hook returns zero for the insn
706 passed as the parameter, the insn will not be chosen to be
707 issued. This hook is used to discard speculative instructions,
708 that stand at the first position of the ready list. */
710 (first_cycle_multipass_dfa_lookahead_guard_spec,
712 bool, (const_rtx insn), NULL)
714 /* The following member value is a pointer to a function that provides
715 information about the speculation capabilities of the target.
716 The parameter is a pointer to spec_info variable. */
720 void, (struct spec_info_def *spec_info), NULL)
724 "Return speculation types of instruction @var{insn}.",
725 int, (rtx insn), NULL)
728 (get_insn_checked_ds,
729 "Return speculation types that are checked for instruction @var{insn}",
730 int, (rtx insn), NULL)
734 "Return bool if rtx scanning should just skip current layer and\
735 advance to the inner rtxes.",
736 bool, (const_rtx x), NULL)
738 /* The following member value is a pointer to a function that provides
739 information about the target resource-based lower bound which is
740 used by the swing modulo scheduler. The parameter is a pointer
745 int, (struct ddg *g), NULL)
747 HOOK_VECTOR_END (sched)
749 /* Functions relating to vectorization. */
751 #define HOOK_PREFIX "TARGET_VECTORIZE_"
752 HOOK_VECTOR (TARGET_VECTORIZE, vectorize)
754 /* The following member value is a pointer to a function called
755 by the vectorizer, and return the decl of the target builtin
758 (builtin_mask_for_load,
762 /* Returns a code for builtin that realizes vectorized version of
763 function, or NULL_TREE if not available. */
765 (builtin_vectorized_function,
767 tree, (tree fndecl, tree vec_type_out, tree vec_type_in),
768 default_builtin_vectorized_function)
770 /* Returns a function declaration for a builtin that realizes the
771 vector conversion, or NULL_TREE if not available. */
775 tree, (unsigned code, tree dest_type, tree src_type),
776 default_builtin_vectorized_conversion)
778 /* Target builtin that implements vector widening multiplication.
779 builtin_mul_widen_eve computes the element-by-element products
780 for the even elements, and builtin_mul_widen_odd computes the
781 element-by-element products for the odd elements. */
783 (builtin_mul_widen_even,
785 tree, (tree x), NULL)
788 (builtin_mul_widen_odd,
790 tree, (tree x), NULL)
792 /* Cost of different vector/scalar statements in vectorization cost model. */
794 (builtin_vectorization_cost,
796 int, (enum vect_cost_for_stmt type_of_cost),
797 default_builtin_vectorization_cost)
799 /* Return true if vector alignment is reachable (by peeling N
800 iterations) for the given type. */
802 (vector_alignment_reachable,
804 bool, (const_tree type, bool is_packed),
805 default_builtin_vector_alignment_reachable)
807 /* Target builtin that implements vector permute. */
811 tree, (tree type, tree *mask_element_type), NULL)
813 /* Return true if a vector created for builtin_vec_perm is valid. */
815 (builtin_vec_perm_ok,
817 bool, (tree vec_type, tree mask),
818 hook_bool_tree_tree_true)
820 /* Return true if the target supports misaligned store/load of a
821 specific factor denoted in the third parameter. The last parameter
822 is true if the access is defined in a packed struct. */
824 (support_vector_misalignment,
827 (enum machine_mode mode, const_tree type, int misalignment, bool is_packed),
828 default_builtin_support_vector_misalignment)
830 HOOK_VECTOR_END (vectorize)
833 #define HOOK_PREFIX "TARGET_"
835 /* The initial value of target_flags. */
837 (default_target_flags,
841 /* Allow target specific overriding of option settings after options have
842 been changed by an attribute or pragma or when it is reset at the
843 end of the code affected by an attribute or pragma. */
845 (override_options_after_change,
850 /* Handle target switch CODE (an OPT_* value). ARG is the argument
851 passed to the switch; it is NULL if no argument was. VALUE is the
852 value of ARG if CODE specifies a UInteger option, otherwise it is
853 1 if the positive form of the switch was used and 0 if the negative
854 form was. Return true if the switch was valid. */
858 bool, (size_t code, const char *arg, int value),
859 hook_bool_size_t_constcharptr_int_true)
861 /* ??? Documenting this hook requires a GFDL license grant. */
864 "Handle target-specific parts of specifying -Ofast.",
868 /* Display extra, target specific information in response to a
869 --target-help switch. */
876 (eh_return_filter_mode,
877 "Return machine mode for filter value.",
878 enum machine_mode, (void),
879 default_eh_return_filter_mode)
881 /* Return machine mode for libgcc expanded cmp instructions. */
883 (libgcc_cmp_return_mode,
885 enum machine_mode, (void),
886 default_libgcc_cmp_return_mode)
888 /* Return machine mode for libgcc expanded shift instructions. */
890 (libgcc_shift_count_mode,
892 enum machine_mode, (void),
893 default_libgcc_shift_count_mode)
895 /* Return machine mode to be used for _Unwind_Word type. */
899 enum machine_mode, (void),
900 default_unwind_word_mode)
902 /* Given two decls, merge their attributes and return the result. */
904 (merge_decl_attributes,
906 tree, (tree olddecl, tree newdecl),
907 merge_decl_attributes)
909 /* Given two types, merge their attributes and return the result. */
911 (merge_type_attributes,
913 tree, (tree type1, tree type2),
914 merge_type_attributes)
916 /* Table of machine attributes and functions to handle them.
921 const struct attribute_spec *, NULL)
923 /* Return true iff attribute NAME expects a plain identifier as its first
926 (attribute_takes_identifier_p,
928 bool, (const_tree name),
929 hook_bool_const_tree_false)
931 /* Return zero if the attributes on TYPE1 and TYPE2 are incompatible,
932 one if they are compatible and two if they are nearly compatible
933 (which causes a warning to be generated). */
935 (comp_type_attributes,
937 int, (const_tree type1, const_tree type2),
938 hook_int_const_tree_const_tree_1)
940 /* Assign default attributes to the newly defined TYPE. */
942 (set_default_type_attributes,
947 /* Insert attributes on the newly created DECL. */
951 void, (tree node, tree *attr_ptr),
952 hook_void_tree_treeptr)
954 /* Return true if FNDECL (which has at least one machine attribute)
955 can be inlined despite its machine attributes, false otherwise. */
957 (function_attribute_inlinable_p,
959 bool, (const_tree fndecl),
960 hook_bool_const_tree_false)
962 /* Return true if bitfields in RECORD_TYPE should follow the
963 Microsoft Visual C++ bitfield layout rules. */
965 (ms_bitfield_layout_p,
967 bool, (const_tree record_type),
968 hook_bool_const_tree_false)
970 /* True if the target supports decimal floating point. */
972 (decimal_float_supported_p,
975 default_decimal_float_supported_p)
977 /* True if the target supports fixed-point. */
979 (fixed_point_supported_p,
982 default_fixed_point_supported_p)
984 /* Return true if anonymous bitfields affect structure alignment. */
986 (align_anon_bitfield,
989 hook_bool_void_false)
991 /* Return true if volatile bitfields should use the narrowest type possible.
992 Return false if they should use the container type. */
994 (narrow_volatile_bitfield,
997 hook_bool_void_false)
999 /* Set up target-specific built-in functions. */
1006 /* Initialize (if INITIALIZE_P is true) and return the target-specific
1007 built-in function decl for CODE.
1008 Return NULL if that is not possible. Return error_mark_node if CODE
1009 is outside of the range of valid target builtin function codes. */
1013 tree, (unsigned code, bool initialize_p), NULL)
1015 /* Expand a target-specific builtin. */
1020 (tree exp, rtx target, rtx subtarget, enum machine_mode mode, int ignore),
1021 default_expand_builtin)
1023 /* Select a replacement for a target-specific builtin. This is done
1024 *before* regular type checking, and so allows the target to
1025 implement a crude form of function overloading. The result is a
1026 complete expression that implements the operation. PARAMS really
1027 has type VEC(tree,gc)*, but we don't want to include tree.h here. */
1029 (resolve_overloaded_builtin,
1031 tree, (unsigned int /*location_t*/ loc, tree fndecl, void *arglist), NULL)
1033 /* Fold a target-specific builtin. */
1037 tree, (tree fndecl, int n_args, tree *argp, bool ignore),
1038 hook_tree_tree_int_treep_bool_null)
1040 /* Returns a code for a target-specific builtin that implements
1041 reciprocal of the function, or NULL_TREE if not available. */
1043 (builtin_reciprocal,
1045 tree, (unsigned fn, bool md_fn, bool sqrt),
1046 default_builtin_reciprocal)
1048 /* For a vendor-specific TYPE, return a pointer to a statically-allocated
1049 string containing the C++ mangling for TYPE. In all other cases, return
1054 const char *, (const_tree type),
1055 hook_constcharptr_const_tree_null)
1057 /* Make any adjustments to libfunc names needed for this target. */
1064 /* Given a decl, a section name, and whether the decl initializer
1065 has relocs, choose attributes for the section. */
1066 /* ??? Should be merged with SELECT_SECTION and UNIQUE_SECTION. */
1068 (section_type_flags,
1070 unsigned int, (tree decl, const char *name, int reloc),
1071 default_section_type_flags)
1073 /* True if new jumps cannot be created, to replace existing ones or
1074 not, at the current point in the compilation. */
1076 (cannot_modify_jumps_p,
1079 hook_bool_void_false)
1081 /* Return a register class for which branch target register
1082 optimizations should be applied. */
1084 (branch_target_register_class,
1086 reg_class_t, (void),
1087 default_branch_target_register_class)
1089 /* Return true if branch target register optimizations should include
1090 callee-saved registers that are not already live during the current
1091 function. AFTER_PE_GEN is true if prologues and epilogues have
1092 already been generated. */
1094 (branch_target_register_callee_saved,
1096 bool, (bool after_prologue_epilogue_gen),
1097 hook_bool_bool_false)
1099 /* Return true if the target supports conditional execution. */
1101 (have_conditional_execution,
1104 default_have_conditional_execution)
1106 /* Return a new value for loop unroll size. */
1108 (loop_unroll_adjust,
1110 unsigned, (unsigned nunroll, struct loop *loop),
1113 /* True if the constant X cannot be placed in the constant pool. */
1115 (cannot_force_const_mem,
1118 hook_bool_rtx_false)
1121 (cannot_copy_insn_p,
1122 "True if the insn @var{x} cannot be duplicated.",
1125 /* True if X is considered to be commutative. */
1129 bool, (const_rtx x, int outer_code),
1130 hook_bool_const_rtx_commutative_p)
1132 /* True if ADDR is an address-expression whose effect depends
1133 on the mode of the memory reference it is used in. */
1135 (mode_dependent_address_p,
1137 bool, (const_rtx addr),
1138 default_mode_dependent_address_p)
1140 /* Given an invalid address X for a given machine mode, try machine-specific
1141 ways to make it legitimate. Return X or an invalid address on failure. */
1143 (legitimize_address,
1145 rtx, (rtx x, rtx oldx, enum machine_mode mode),
1146 default_legitimize_address)
1148 /* Given an address RTX, undo the effects of LEGITIMIZE_ADDRESS. */
1150 (delegitimize_address,
1153 delegitimize_mem_from_attrs)
1155 /* Given an address RTX, say whether it is valid. */
1157 (legitimate_address_p,
1159 bool, (enum machine_mode mode, rtx x, bool strict),
1160 default_legitimate_address_p)
1162 /* True if the given constant can be put into an object_block. */
1164 (use_blocks_for_constant_p,
1166 bool, (enum machine_mode mode, const_rtx x),
1167 hook_bool_mode_const_rtx_false)
1169 /* The minimum and maximum byte offsets for anchored addresses. */
1180 /* True if section anchors can be used to access the given symbol. */
1182 (use_anchors_for_symbol_p,
1184 bool, (const_rtx x),
1185 default_use_anchors_for_symbol_p)
1187 /* True if it is OK to do sibling call optimization for the specified
1188 call expression EXP. DECL will be the called function, or NULL if
1189 this is an indirect call. */
1191 (function_ok_for_sibcall,
1193 bool, (tree decl, tree exp),
1194 hook_bool_tree_tree_false)
1196 /* Establish appropriate back-end context for processing the function
1197 FNDECL. The argument might be NULL to indicate processing at top
1198 level, outside of any function scope. */
1200 (set_current_function,
1202 void, (tree decl), hook_void_tree)
1204 /* True if EXP should be placed in a "small data" section. */
1208 bool, (const_tree exp),
1209 hook_bool_const_tree_false)
1211 /* True if EXP names an object for which name resolution must resolve
1212 to the current executable or shared library. */
1216 bool, (const_tree exp),
1217 default_binds_local_p)
1219 /* Modify and return the identifier of a DECL's external name,
1220 originally identified by ID, as required by the target,
1221 (eg, append @nn to windows32 stdcall function names).
1222 The default is to return ID without modification. */
1224 (mangle_decl_assembler_name,
1226 tree, (tree decl, tree id),
1227 default_mangle_decl_assembler_name)
1229 /* Do something target-specific to record properties of the DECL into
1230 the associated SYMBOL_REF. */
1232 (encode_section_info,
1234 void, (tree decl, rtx rtl, int new_decl_p),
1235 default_encode_section_info)
1237 /* Undo the effects of encode_section_info on the symbol string. */
1239 (strip_name_encoding,
1241 const char *, (const char *name),
1242 default_strip_name_encoding)
1244 /* If shift optabs for MODE are known to always truncate the shift count,
1245 return the mask that they apply. Return 0 otherwise. */
1247 (shift_truncation_mask,
1249 unsigned HOST_WIDE_INT, (enum machine_mode mode),
1250 default_shift_truncation_mask)
1252 /* Return the number of divisions in the given MODE that should be present,
1253 so that it is profitable to turn the division into a multiplication by
1256 (min_divisions_for_recip_mul,
1258 unsigned int, (enum machine_mode mode),
1259 default_min_divisions_for_recip_mul)
1261 /* If the representation of integral MODE is such that values are
1262 always sign-extended to a wider mode MODE_REP then return
1263 SIGN_EXTEND. Return UNKNOWN otherwise. */
1264 /* Note that the return type ought to be RTX_CODE, but that's not
1265 necessarily defined at this point. */
1269 int, (enum machine_mode mode, enum machine_mode rep_mode),
1270 default_mode_rep_extended)
1272 /* True if MODE is valid for a pointer in __attribute__((mode("MODE"))). */
1274 (valid_pointer_mode,
1276 bool, (enum machine_mode mode),
1277 default_valid_pointer_mode)
1279 /* Support for named address spaces. */
1281 #define HOOK_PREFIX "TARGET_ADDR_SPACE_"
1282 HOOK_VECTOR (TARGET_ADDR_SPACE_HOOKS, addr_space)
1284 /* MODE to use for a pointer into another address space. */
1288 enum machine_mode, (addr_space_t address_space),
1289 default_addr_space_pointer_mode)
1291 /* MODE to use for an address in another address space. */
1295 enum machine_mode, (addr_space_t address_space),
1296 default_addr_space_address_mode)
1298 /* True if MODE is valid for a pointer in __attribute__((mode("MODE")))
1299 in another address space. */
1301 (valid_pointer_mode,
1303 bool, (enum machine_mode mode, addr_space_t as),
1304 default_addr_space_valid_pointer_mode)
1306 /* True if an address is a valid memory address to a given named address
1307 space for a given mode. */
1309 (legitimate_address_p,
1311 bool, (enum machine_mode mode, rtx exp, bool strict, addr_space_t as),
1312 default_addr_space_legitimate_address_p)
1314 /* Return an updated address to convert an invalid pointer to a named
1315 address space to a valid one. If NULL_RTX is returned use machine
1316 independent methods to make the address valid. */
1318 (legitimize_address,
1320 rtx, (rtx x, rtx oldx, enum machine_mode mode, addr_space_t as),
1321 default_addr_space_legitimize_address)
1323 /* True if one named address space is a subset of another named address. */
1327 bool, (addr_space_t superset, addr_space_t subset),
1328 default_addr_space_subset_p)
1330 /* Function to convert an rtl expression from one address space to another. */
1334 rtx, (rtx op, tree from_type, tree to_type),
1335 default_addr_space_convert)
1337 HOOK_VECTOR_END (addr_space)
1340 #define HOOK_PREFIX "TARGET_"
1342 /* True if MODE is valid for the target. By "valid", we mean able to
1343 be manipulated in non-trivial ways. In particular, this means all
1344 the arithmetic is supported. */
1346 (scalar_mode_supported_p,
1348 bool, (enum machine_mode mode),
1349 default_scalar_mode_supported_p)
1351 /* Similarly for vector modes. "Supported" here is less strict. At
1352 least some operations are supported; need to check optabs or builtins
1353 for further details. */
1355 (vector_mode_supported_p,
1357 bool, (enum machine_mode mode),
1358 hook_bool_mode_false)
1360 /* Compute cost of moving data from a register of class FROM to one of
1363 (register_move_cost,
1365 int, (enum machine_mode mode, reg_class_t from, reg_class_t to),
1366 default_register_move_cost)
1368 /* Compute cost of moving registers to/from memory. */
1369 /* ??? Documenting the argument types for this hook requires a GFDL
1370 license grant. Also, the documentation uses a different name for RCLASS. */
1374 int, (enum machine_mode mode, reg_class_t rclass, bool in),
1375 default_memory_move_cost)
1377 /* True for MODE if the target expects that registers in this mode will
1378 be allocated to registers in a small register class. The compiler is
1379 allowed to use registers explicitly used in the rtl as spill registers
1380 but it should prevent extending the lifetime of these registers. */
1382 (small_register_classes_for_mode_p,
1384 bool, (enum machine_mode mode),
1385 hook_bool_mode_false)
1387 /* Compute a (partial) cost for rtx X. Return true if the complete
1388 cost has been computed, and false if subexpressions should be
1389 scanned. In either case, *TOTAL contains the cost result. */
1390 /* Note that CODE and OUTER_CODE ought to be RTX_CODE, but that's
1391 not necessarily defined at this point. */
1395 bool, (rtx x, int code, int outer_code, int *total, bool speed),
1396 hook_bool_rtx_int_int_intp_bool_false)
1398 /* Compute the cost of X, used as an address. Never called with
1399 invalid addresses. */
1403 int, (rtx address, bool speed),
1404 default_address_cost)
1406 /* Return where to allocate pseudo for a given hard register initial value. */
1408 (allocate_initial_value,
1410 rtx, (rtx hard_reg), NULL)
1412 /* Return nonzero if evaluating UNSPEC[_VOLATILE] X might cause a trap.
1413 FLAGS has the same meaning as in rtlanal.c: may_trap_p_1. */
1417 int, (const_rtx x, unsigned flags),
1418 default_unspec_may_trap_p)
1420 /* Given a register, this hook should return a parallel of registers
1421 to represent where to find the register pieces. Define this hook
1422 if the register and its mode are represented in Dwarf in
1423 non-contiguous locations, or if the register should be
1424 represented in more than one register in Dwarf. Otherwise, this
1425 hook should return NULL_RTX. */
1427 (dwarf_register_span,
1432 /* If expand_builtin_init_dwarf_reg_sizes needs to fill in table
1433 entries not corresponding directly to registers below
1434 FIRST_PSEUDO_REGISTER, this hook should generate the necessary
1435 code, given the address of the table. */
1437 (init_dwarf_reg_sizes_extra,
1439 void, (tree address),
1442 /* Fetch the fixed register(s) which hold condition codes, for
1443 targets where it makes sense to look for duplicate assignments to
1444 the condition codes. This should return true if there is such a
1445 register, false otherwise. The arguments should be set to the
1446 fixed register numbers. Up to two condition code registers are
1447 supported. If there is only one for this target, the int pointed
1448 at by the second argument should be set to -1. */
1450 (fixed_condition_code_regs,
1452 bool, (unsigned int *p1, unsigned int *p2),
1453 hook_bool_uintp_uintp_false)
1455 /* If two condition code modes are compatible, return a condition
1456 code mode which is compatible with both, such that a comparison
1457 done in the returned mode will work for both of the original
1458 modes. If the condition code modes are not compatible, return
1461 (cc_modes_compatible,
1463 enum machine_mode, (enum machine_mode m1, enum machine_mode m2),
1464 default_cc_modes_compatible)
1466 /* Do machine-dependent code transformations. Called just before
1467 delayed-branch scheduling. */
1469 (machine_dependent_reorg,
1473 /* Create the __builtin_va_list type. */
1475 (build_builtin_va_list,
1478 std_build_builtin_va_list)
1480 /* Enumerate the va list variants. */
1484 int, (int idx, const char **pname, tree *ptree),
1487 /* Get the cfun/fndecl calling abi __builtin_va_list type. */
1491 tree, (tree fndecl),
1494 /* Get the __builtin_va_list type dependent on input type. */
1496 (canonical_va_list_type,
1499 std_canonical_va_list_type)
1501 /* ??? Documenting this hook requires a GFDL license grant. */
1503 (expand_builtin_va_start,
1504 "Expand the @code{__builtin_va_start} builtin.",
1505 void, (tree valist, rtx nextarg), NULL)
1507 /* Gimplifies a VA_ARG_EXPR. */
1509 (gimplify_va_arg_expr,
1511 tree, (tree valist, tree type, gimple_seq *pre_p, gimple_seq *post_p),
1512 std_gimplify_va_arg_expr)
1514 /* Validity-checking routines for PCH files, target-specific.
1515 get_pch_validity returns a pointer to the data to be stored,
1516 and stores the size in its argument. pch_valid_p gets the same
1517 information back and returns NULL if the PCH is valid,
1518 or an error message if not. */
1522 void *, (size_t *sz),
1523 default_get_pch_validity)
1528 const char *, (const void *data, size_t sz),
1529 default_pch_valid_p)
1531 /* If nonnull, this function checks whether a PCH file with the
1532 given set of target flags can be used. It returns NULL if so,
1533 otherwise it returns an error message. */
1535 (check_pch_target_flags,
1537 const char *, (int pch_flags), NULL)
1539 /* True if the compiler should give an enum type only as many
1540 bytes as it takes to represent the range of possible values of
1543 (default_short_enums,
1546 hook_bool_void_false)
1548 /* This target hook returns an rtx that is used to store the address
1549 of the current frame into the built-in setjmp buffer. */
1551 (builtin_setjmp_frame_value,
1554 default_builtin_setjmp_frame_value)
1556 /* This target hook should add STRING_CST trees for any hard regs
1557 the port wishes to automatically clobber for an asm. */
1561 tree, (tree outputs, tree inputs, tree clobbers),
1562 hook_tree_tree_tree_tree_3rd_identity)
1564 /* This target hook allows the backend to specify a calling convention
1565 in the debug information. This function actually returns an
1566 enum dwarf_calling_convention, but because of forward declarations
1567 and not wanting to include dwarf2.h everywhere target.h is included
1568 the function is being declared as an int. */
1570 (dwarf_calling_convention,
1572 int, (const_tree function),
1573 hook_int_const_tree_0)
1575 /* This target hook allows the backend to emit frame-related insns that
1576 contain UNSPECs or UNSPEC_VOLATILEs. The call frame debugging info
1577 engine will invoke it on insns of the form
1578 (set (reg) (unspec [...] UNSPEC_INDEX))
1580 (set (reg) (unspec_volatile [...] UNSPECV_INDEX))
1581 to let the backend emit the call frame instructions. */
1583 (dwarf_handle_frame_unspec,
1585 void, (const char *label, rtx pattern, int index), NULL)
1587 /* ??? Documenting this hook requires a GFDL license grant. */
1589 (stdarg_optimize_hook,
1590 "Perform architecture specific checking of statements gimplified\
1591 from @code{VA_ARG_EXPR}. @var{stmt} is the statement. Returns true if\
1592 the statement doesn't need to be checked for @code{va_list} references.",
1593 bool, (struct stdarg_info *ai, const_gimple stmt), NULL)
1595 /* This target hook allows the operating system to override the DECL
1596 that represents the external variable that contains the stack
1597 protection guard variable. The type of this DECL is ptr_type_node. */
1599 (stack_protect_guard,
1602 default_stack_protect_guard)
1604 /* This target hook allows the operating system to override the CALL_EXPR
1605 that is invoked when a check vs the guard variable fails. */
1607 (stack_protect_fail,
1610 default_external_stack_protect_fail)
1612 /* Returns NULL if target supports the insn within a doloop block,
1613 otherwise it returns an error message. */
1615 (invalid_within_doloop,
1617 const char *, (const_rtx insn),
1618 default_invalid_within_doloop)
1621 (valid_dllimport_attribute_p,
1622 "@var{decl} is a variable or function with @code{__attribute__((dllimport))}\
1623 specified. Use this hook if the target needs to add extra validation\
1624 checks to @code{handle_dll_attribute}.",
1625 bool, (const_tree decl),
1626 hook_bool_const_tree_true)
1628 /* If non-zero, align constant anchors in CSE to a multiple of this
1633 unsigned HOST_WIDE_INT, 0)
1635 /* Functions relating to calls - argument passing, returns, etc. */
1636 /* Members of struct call have no special macro prefix. */
1637 HOOK_VECTOR (TARGET_CALLS, calls)
1640 (promote_function_mode,
1642 enum machine_mode, (const_tree type, enum machine_mode mode, int *punsignedp,
1643 const_tree funtype, int for_return),
1644 default_promote_function_mode)
1647 (promote_prototypes,
1649 bool, (const_tree fntype),
1650 hook_bool_const_tree_false)
1655 rtx, (tree fndecl, int incoming),
1656 hook_rtx_tree_int_null)
1660 bool, (const_tree type, const_tree fntype),
1661 default_return_in_memory)
1666 bool, (const_tree type),
1667 hook_bool_const_tree_false)
1669 /* Return true if a parameter must be passed by reference. TYPE may
1670 be null if this is a libcall. CA may be null if this query is
1671 from __builtin_va_arg. */
1676 (CUMULATIVE_ARGS *cum, enum machine_mode mode, const_tree type, bool named),
1677 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false)
1680 (expand_builtin_saveregs,
1683 default_expand_builtin_saveregs)
1685 /* Returns pretend_argument_size. */
1687 (setup_incoming_varargs,
1689 void, (CUMULATIVE_ARGS *args_so_far, enum machine_mode mode, tree type,
1690 int *pretend_args_size, int second_time),
1691 default_setup_incoming_varargs)
1694 (strict_argument_naming,
1696 bool, (CUMULATIVE_ARGS *ca),
1697 hook_bool_CUMULATIVE_ARGS_false)
1699 /* Returns true if we should use
1700 targetm.calls.setup_incoming_varargs() and/or
1701 targetm.calls.strict_argument_naming(). */
1703 (pretend_outgoing_varargs_named,
1705 bool, (CUMULATIVE_ARGS *ca),
1706 default_pretend_outgoing_varargs_named)
1708 /* Given a complex type T, return true if a parameter of type T
1709 should be passed as two scalars. */
1713 bool, (const_tree type), NULL)
1715 /* Return true if type T, mode MODE, may not be passed in registers,
1716 but must be passed on the stack. */
1717 /* ??? This predicate should be applied strictly after pass-by-reference.
1718 Need audit to verify that this is the case. */
1720 (must_pass_in_stack,
1722 bool, (enum machine_mode mode, const_tree type),
1723 must_pass_in_stack_var_size_or_pad)
1725 /* Return true if type TYPE, mode MODE, which is passed by reference,
1726 should have the object copy generated by the callee rather than
1727 the caller. It is never called for TYPE requiring constructors. */
1732 (CUMULATIVE_ARGS *cum, enum machine_mode mode, const_tree type, bool named),
1733 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false)
1735 /* Return zero for arguments passed entirely on the stack or entirely
1736 in registers. If passed in both, return the number of bytes passed
1737 in registers; the balance is therefore passed on the stack. */
1741 int, (CUMULATIVE_ARGS *cum, enum machine_mode mode, tree type, bool named),
1742 hook_int_CUMULATIVE_ARGS_mode_tree_bool_0)
1744 /* Update the state in CA to advance past an argument in the
1745 argument list. The values MODE, TYPE, and NAMED describe that
1747 /* ??? tm.texi still only describes the old macro. */
1749 (function_arg_advance,
1752 (CUMULATIVE_ARGS *ca, enum machine_mode mode, const_tree type, bool named),
1753 default_function_arg_advance)
1755 /* Return zero if the argument described by the state of CA should
1756 be placed on a stack, or a hard register in which to store the
1757 argument. The values MODE, TYPE, and NAMED describe that
1759 /* ??? tm.texi still only describes the old macro. */
1763 rtx, (const CUMULATIVE_ARGS *ca, enum machine_mode mode, const_tree type,
1765 default_function_arg)
1767 /* Likewise, but for machines with register windows. Return the
1768 location where the argument will appear to the callee. */
1769 /* ??? tm.texi still only describes the old macro. */
1771 (function_incoming_arg,
1773 rtx, (const CUMULATIVE_ARGS *ca, enum machine_mode mode, const_tree type,
1775 default_function_incoming_arg)
1777 /* Return the diagnostic message string if function without a prototype
1778 is not allowed for this 'val' argument; NULL otherwise. */
1780 (invalid_arg_for_unprototyped_fn,
1782 const char *, (const_tree typelist, const_tree funcdecl, const_tree val),
1783 hook_invalid_arg_for_unprototyped_fn)
1785 /* Return an rtx for the return value location of the function
1786 specified by FN_DECL_OR_TYPE with a return type of RET_TYPE. */
1790 rtx, (const_tree ret_type, const_tree fn_decl_or_type, bool outgoing),
1791 default_function_value)
1793 /* Return the rtx for the result of a libcall of mode MODE,
1794 calling the function FN_NAME. */
1798 rtx, (enum machine_mode mode, const_rtx fun),
1799 default_libcall_value)
1801 /* Return true if REGNO is a possible register number for
1802 a function value as seen by the caller. */
1804 (function_value_regno_p,
1806 bool, (const unsigned int regno),
1807 default_function_value_regno_p)
1809 /* ??? Documenting this hook requires a GFDL license grant. */
1811 (internal_arg_pointer,
1812 "Return an rtx for the argument pointer incoming to the\
1815 default_internal_arg_pointer)
1817 /* Update the current function stack boundary if needed. */
1819 (update_stack_boundary,
1823 /* Handle stack alignment and return an rtx for Dynamic Realign
1824 Argument Pointer if necessary. */
1830 /* Return true if all function parameters should be spilled to the
1833 (allocate_stack_slots_for_args,
1836 hook_bool_void_true)
1838 /* Return an rtx for the static chain for FNDECL. If INCOMING_P is true,
1839 then it should be for the callee; otherwise for the caller. */
1843 rtx, (const_tree fndecl, bool incoming_p),
1844 default_static_chain)
1846 /* Fill in the trampoline at MEM with a call to FNDECL and a
1847 static chain value of CHAIN. */
1851 void, (rtx m_tramp, tree fndecl, rtx static_chain),
1852 default_trampoline_init)
1854 /* Adjust the address of the trampoline in a target-specific way. */
1856 (trampoline_adjust_address,
1858 rtx, (rtx addr), NULL)
1860 /* Return the number of bytes of its own arguments that a function
1861 pops on returning, or 0 if the function pops no arguments and the
1862 caller must therefore pop them all after the function returns. */
1863 /* ??? tm.texi has no types for the parameters. */
1867 int, (tree fundecl, tree funtype, int size),
1868 default_return_pops_args)
1870 HOOK_VECTOR_END (calls)
1872 /* Return the diagnostic message string if conversion from FROMTYPE
1873 to TOTYPE is not allowed, NULL otherwise. */
1875 (invalid_conversion,
1877 const char *, (const_tree fromtype, const_tree totype),
1878 hook_constcharptr_const_tree_const_tree_null)
1880 /* Return the diagnostic message string if the unary operation OP is
1881 not permitted on TYPE, NULL otherwise. */
1885 const char *, (int op, const_tree type),
1886 hook_constcharptr_int_const_tree_null)
1888 /* Return the diagnostic message string if the binary operation OP
1889 is not permitted on TYPE1 and TYPE2, NULL otherwise. */
1893 const char *, (int op, const_tree type1, const_tree type2),
1894 hook_constcharptr_int_const_tree_const_tree_null)
1896 /* Return the diagnostic message string if TYPE is not valid as a
1897 function parameter type, NULL otherwise. */
1899 (invalid_parameter_type,
1901 const char *, (const_tree type),
1902 hook_constcharptr_const_tree_null)
1904 /* Return the diagnostic message string if TYPE is not valid as a
1905 function return type, NULL otherwise. */
1907 (invalid_return_type,
1909 const char *, (const_tree type),
1910 hook_constcharptr_const_tree_null)
1912 /* If values of TYPE are promoted to some other type when used in
1913 expressions (analogous to the integer promotions), return that type,
1914 or NULL_TREE otherwise. */
1918 tree, (const_tree type),
1919 hook_tree_const_tree_null)
1921 /* Convert EXPR to TYPE, if target-specific types with special conversion
1922 rules are involved. Return the converted expression, or NULL to apply
1923 the standard conversion rules. */
1927 tree, (tree type, tree expr),
1928 hook_tree_tree_tree_null)
1930 /* Return the array of IRA cover classes for the current target. */
1934 const reg_class_t *, (void),
1935 default_ira_cover_classes)
1937 /* Return the class for a secondary reload, and fill in extra information. */
1942 (bool in_p, rtx x, reg_class_t reload_class, enum machine_mode reload_mode,
1943 secondary_reload_info *sri),
1944 default_secondary_reload)
1946 /* This target hook allows the backend to perform additional
1947 processing while initializing for variable expansion. */
1949 (expand_to_rtl_hook,
1954 /* This target hook allows the backend to perform additional
1955 instantiations on rtx that are not actually in insns yet,
1956 but will be later. */
1963 /* Return true if is OK to use a hard register REGNO as scratch register
1966 (hard_regno_scratch_ok,
1968 bool, (unsigned int regno),
1969 default_hard_regno_scratch_ok)
1971 /* Return the smallest number of different values for which it is best to
1972 use a jump-table instead of a tree of conditional branches. */
1974 (case_values_threshold,
1976 unsigned int, (void),
1977 default_case_values_threshold)
1979 /* Retutn true if a function must have and use a frame pointer. */
1981 (frame_pointer_required,
1984 hook_bool_void_false)
1986 /* Returns true if the compiler is allowed to try to replace register number
1987 from-reg with register number to-reg. */
1991 bool, (const int from_reg, const int to_reg),
1992 hook_bool_const_int_const_int_true)
1994 /* Functions specific to the C family of frontends. */
1996 #define HOOK_PREFIX "TARGET_C_"
1997 HOOK_VECTOR (TARGET_C, c)
1999 /* ??? Documenting this hook requires a GFDL license grant. */
2002 "Return machine mode for non-standard constant literal suffix @var{c},\
2003 or VOIDmode if non-standard suffixes are unsupported.",
2004 enum machine_mode, (char c),
2005 default_mode_for_suffix)
2009 /* Functions specific to the C++ frontend. */
2011 #define HOOK_PREFIX "TARGET_CXX_"
2012 HOOK_VECTOR (TARGET_CXX, cxx)
2014 /* Return the integer type used for guard variables. */
2019 default_cxx_guard_type)
2021 /* Return true if only the low bit of the guard should be tested. */
2026 hook_bool_void_false)
2028 /* Returns the size of the array cookie for an array of type. */
2033 default_cxx_get_cookie_size)
2035 /* Returns true if the element size should be stored in the array cookie. */
2040 hook_bool_void_false)
2042 /* Allows backends to perform additional processing when
2043 deciding if a class should be exported or imported. */
2045 (import_export_class,
2047 int, (tree type, int import_export), NULL)
2049 /* Returns true if constructors and destructors return "this". */
2051 (cdtor_returns_this,
2054 hook_bool_void_false)
2056 /* Returns true if the key method for a class can be an inline
2057 function, so long as it is not declared inline in the class
2058 itself. Returning true is the behavior required by the Itanium C++ ABI. */
2060 (key_method_may_be_inline,
2063 hook_bool_void_true)
2066 (determine_class_data_visibility,
2067 "@var{decl} is a virtual table, virtual table table, typeinfo object,\
2068 or other similar implicit class data object that will be emitted with\
2069 external linkage in this translation unit. No ELF visibility has been\
2070 explicitly specified. If the target needs to specify a visibility\
2071 other than that of the containing class, use this hook to set\
2072 @code{DECL_VISIBILITY} and @code{DECL_VISIBILITY_SPECIFIED}.",
2076 /* Returns true (the default) if virtual tables and other
2077 similar implicit class data objects are always COMDAT if they
2078 have external linkage. If this hook returns false, then
2079 class data for classes whose virtual table will be emitted in
2080 only one translation unit will not be COMDAT. */
2082 (class_data_always_comdat,
2085 hook_bool_void_true)
2087 /* Returns true (the default) if the RTTI for the basic types,
2088 which is always defined in the C++ runtime, should be COMDAT;
2089 false if it should not be COMDAT. */
2091 (library_rtti_comdat,
2094 hook_bool_void_true)
2096 /* Returns true if __aeabi_atexit should be used to register static
2102 hook_bool_void_false)
2104 /* Returns true if target may use atexit in the same manner as
2105 __cxa_atexit to register static destructors. */
2107 (use_atexit_for_cxa_atexit,
2110 hook_bool_void_false)
2113 (adjust_class_at_definition,
2114 "@var{type} is a C++ class (i.e., RECORD_TYPE or UNION_TYPE) that has just\
2115 been defined. Use this hook to make adjustments to the class (eg, tweak\
2116 visibility or perform any other required target modifications).",
2120 HOOK_VECTOR_END (cxx)
2122 /* Functions and data for emulated TLS support. */
2124 #define HOOK_PREFIX "TARGET_EMUTLS_"
2125 HOOK_VECTOR (TARGET_EMUTLS, emutls)
2127 /* Name of the address and common functions. */
2131 const char *, "__builtin___emutls_get_address")
2136 const char *, "__builtin___emutls_register_common")
2138 /* Prefixes for proxy variable and template. */
2149 /* Prefixes for proxy variable and template. */
2160 /* Function to generate field definitions of the proxy variable. */
2164 tree, (tree type, tree *name),
2165 default_emutls_var_fields)
2167 /* Function to initialize a proxy variable. */
2171 tree, (tree var, tree decl, tree tmpl_addr),
2172 default_emutls_var_init)
2174 /* Whether we are allowed to alter the usual alignment of the
2181 /* Whether we can emit debug information for TLS vars. */
2183 (debug_form_tls_address,
2187 HOOK_VECTOR_END (emutls)
2190 #define HOOK_PREFIX "TARGET_OPTION_"
2191 HOOK_VECTOR (TARGET_OPTION_HOOKS, target_option_hooks)
2193 /* Function to validate the attribute((option(...))) strings or NULL. If
2194 the option is validated, it is assumed that DECL_FUNCTION_SPECIFIC will
2195 be filled in in the function decl node. */
2199 bool, (tree fndecl, tree name, tree args, int flags),
2200 default_target_option_valid_attribute_p)
2202 /* Function to save any extra target state in the target options structure. */
2206 void, (struct cl_target_option *ptr), NULL)
2208 /* Function to restore any extra target state from the target options
2213 void, (struct cl_target_option *ptr), NULL)
2215 /* Function to print any extra target state from the target options
2220 void, (FILE *file, int indent, struct cl_target_option *ptr), NULL)
2222 /* Function to parse arguments to be validated for #pragma option, and to
2223 change the state if the options are valid. If the first argument is
2224 NULL, the second argument specifies the default options to use. Return
2225 true if the options are valid, and set the current state. */
2226 /* ??? The documentation in tm.texi is incomplete. */
2230 bool, (tree args, tree pop_target),
2231 default_target_option_pragma_parse)
2233 /* Do option overrides for the target. */
2238 default_target_option_override)
2240 /* Function to determine if one function can inline another function. */
2242 #define HOOK_PREFIX "TARGET_"
2246 bool, (tree caller, tree callee),
2247 default_target_can_inline_p)
2249 HOOK_VECTOR_END (target_option)
2251 /* For targets that need to mark extra registers as live on entry to
2252 the function, they should define this target hook and set their
2253 bits in the bitmap passed in. */
2255 (extra_live_on_entry,
2257 void, (bitmap regs),
2260 /* Leave the boolean fields at the end. */
2262 /* True if unwinding tables should be generated by default. */
2264 (unwind_tables_default,
2268 /* True if arbitrary sections are supported. */
2270 (have_named_sections,
2274 /* True if we can create zeroed data by switching to a BSS section
2275 and then using ASM_OUTPUT_SKIP to allocate the space. */
2277 (have_switchable_bss_sections,
2281 /* True if "native" constructors and destructors are supported,
2282 false if we're using collect2 for the job. */
2288 /* True if thread-local storage is supported. */
2294 /* True if a small readonly data section is supported. */
2296 (have_srodata_section,
2300 /* True if EH frame info sections should be zero-terminated. */
2302 (terminate_dw2_eh_frame_info,
2306 /* True if #NO_APP should be emitted at the beginning of assembly output. */
2308 (asm_file_start_app_off,
2312 /* True if output_file_directive should be called for main_input_filename
2313 at the beginning of assembly output. */
2315 (asm_file_start_file_directive,
2320 (handle_pragma_extern_prefix,
2321 "True if @code{#pragma extern_prefix} is to be supported.",
2324 /* True if the target is allowed to reorder memory accesses unless
2325 synchronization is explicitly requested. */
2331 /* Returns true if we should generate exception tables for use with the
2332 ARM EABI. The effects the encoding of function exception specifications. */
2338 /* Leave the boolean fields at the end. */
2340 /* Empty macro arguments are undefined in C90, so use an empty macro. */
2341 #define C90_EMPTY_HACK
2342 /* Close the 'struct gcc_target' definition. */
2343 HOOK_VECTOR_END (C90_EMPTY_HACK)
2345 HOOK_VECTOR (TARGETCM_INITIALIZER, gcc_targetcm)
2347 /* Handle target switch CODE (an OPT_* value). ARG is the argument
2348 passed to the switch; it is NULL if no argument was. VALUE is the
2349 value of ARG if CODE specifies a UInteger option, otherwise it is
2350 1 if the positive form of the switch was used and 0 if the negative
2351 form was. Return true if the switch was valid. */
2355 bool, (size_t code, const char *arg, int value),
2356 default_handle_c_option)
2358 HOOK_VECTOR_END (C90_EMPTY_HACK)