1 /* Default target hook functions.
2 Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010
3 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 /* The migration of target macros to target hooks works as follows:
23 1. Create a target hook that uses the existing target macros to
24 implement the same functionality.
26 2. Convert all the MI files to use the hook instead of the macro.
28 3. Repeat for a majority of the remaining target macros. This will
31 4. Tell target maintainers to start migrating.
33 5. Eventually convert the backends to override the hook instead of
34 defining the macros. This will take some time too.
36 6. TBD when, poison the macros. Unmigrated targets will break at
39 Note that we expect steps 1-3 to be done by the people that
40 understand what the MI does with each macro, and step 5 to be done
41 by the target maintainers for their respective targets.
43 Note that steps 1 and 2 don't have to be done together, but no
44 target can override the new hook until step 2 is complete for it.
46 Once the macros are poisoned, we will revert to the old migration
47 rules - migrate the macro, callers, and targets all at once. This
48 comment can thus be removed at that point. */
52 #include "coretypes.h"
59 #include "diagnostic-core.h"
63 #include "target-def.h"
65 #include "hard-reg-set.h"
72 #include "tree-flow.h"
73 #include "tree-ssa-alias.h"
77 default_legitimate_address_p (enum machine_mode mode ATTRIBUTE_UNUSED,
78 rtx addr ATTRIBUTE_UNUSED,
79 bool strict ATTRIBUTE_UNUSED)
81 #ifdef GO_IF_LEGITIMATE_ADDRESS
82 /* Defer to the old implementation using a goto. */
84 return strict_memory_address_p (mode, addr);
86 return memory_address_p (mode, addr);
93 default_external_libcall (rtx fun ATTRIBUTE_UNUSED)
95 #ifdef ASM_OUTPUT_EXTERNAL_LIBCALL
96 ASM_OUTPUT_EXTERNAL_LIBCALL(asm_out_file, fun);
101 default_unspec_may_trap_p (const_rtx x, unsigned flags)
105 if (GET_CODE (x) == UNSPEC_VOLATILE
106 /* Any floating arithmetic may trap. */
107 || (SCALAR_FLOAT_MODE_P (GET_MODE (x))
108 && flag_trapping_math))
111 for (i = 0; i < XVECLEN (x, 0); ++i)
113 if (may_trap_p_1 (XVECEXP (x, 0, i), flags))
121 default_promote_function_mode (const_tree type ATTRIBUTE_UNUSED,
122 enum machine_mode mode,
123 int *punsignedp ATTRIBUTE_UNUSED,
124 const_tree funtype ATTRIBUTE_UNUSED,
125 int for_return ATTRIBUTE_UNUSED)
128 return promote_mode (type, mode, punsignedp);
133 default_promote_function_mode_always_promote (const_tree type,
134 enum machine_mode mode,
136 const_tree funtype ATTRIBUTE_UNUSED,
137 int for_return ATTRIBUTE_UNUSED)
139 return promote_mode (type, mode, punsignedp);
144 default_cc_modes_compatible (enum machine_mode m1, enum machine_mode m2)
152 default_return_in_memory (const_tree type,
153 const_tree fntype ATTRIBUTE_UNUSED)
155 return (TYPE_MODE (type) == BLKmode);
159 default_legitimize_address (rtx x, rtx orig_x ATTRIBUTE_UNUSED,
160 enum machine_mode mode ATTRIBUTE_UNUSED)
166 default_expand_builtin_saveregs (void)
168 error ("__builtin_saveregs not supported by this target");
173 default_setup_incoming_varargs (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
174 enum machine_mode mode ATTRIBUTE_UNUSED,
175 tree type ATTRIBUTE_UNUSED,
176 int *pretend_arg_size ATTRIBUTE_UNUSED,
177 int second_time ATTRIBUTE_UNUSED)
181 /* The default implementation of TARGET_BUILTIN_SETJMP_FRAME_VALUE. */
184 default_builtin_setjmp_frame_value (void)
186 return virtual_stack_vars_rtx;
189 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns false. */
192 hook_bool_CUMULATIVE_ARGS_false (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED)
198 default_pretend_outgoing_varargs_named (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED)
200 return (targetm.calls.setup_incoming_varargs
201 != default_setup_incoming_varargs);
205 default_eh_return_filter_mode (void)
207 return targetm.unwind_word_mode ();
211 default_libgcc_cmp_return_mode (void)
217 default_libgcc_shift_count_mode (void)
223 default_unwind_word_mode (void)
228 /* The default implementation of TARGET_SHIFT_TRUNCATION_MASK. */
230 unsigned HOST_WIDE_INT
231 default_shift_truncation_mask (enum machine_mode mode)
233 return SHIFT_COUNT_TRUNCATED ? GET_MODE_BITSIZE (mode) - 1 : 0;
236 /* The default implementation of TARGET_MIN_DIVISIONS_FOR_RECIP_MUL. */
239 default_min_divisions_for_recip_mul (enum machine_mode mode ATTRIBUTE_UNUSED)
241 return have_insn_for (DIV, mode) ? 3 : 2;
244 /* The default implementation of TARGET_MODE_REP_EXTENDED. */
247 default_mode_rep_extended (enum machine_mode mode ATTRIBUTE_UNUSED,
248 enum machine_mode mode_rep ATTRIBUTE_UNUSED)
253 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns true. */
256 hook_bool_CUMULATIVE_ARGS_true (CUMULATIVE_ARGS * a ATTRIBUTE_UNUSED)
261 /* Return machine mode for non-standard suffix
262 or VOIDmode if non-standard suffixes are unsupported. */
264 default_mode_for_suffix (char suffix ATTRIBUTE_UNUSED)
269 /* The generic C++ ABI specifies this is a 64-bit value. */
271 default_cxx_guard_type (void)
273 return long_long_integer_type_node;
277 /* Returns the size of the cookie to use when allocating an array
278 whose elements have the indicated TYPE. Assumes that it is already
279 known that a cookie is needed. */
282 default_cxx_get_cookie_size (tree type)
286 /* We need to allocate an additional max (sizeof (size_t), alignof
287 (true_type)) bytes. */
291 sizetype_size = size_in_bytes (sizetype);
292 type_align = size_int (TYPE_ALIGN_UNIT (type));
293 if (INT_CST_LT_UNSIGNED (type_align, sizetype_size))
294 cookie_size = sizetype_size;
296 cookie_size = type_align;
301 /* Return true if a parameter must be passed by reference. This version
302 of the TARGET_PASS_BY_REFERENCE hook uses just MUST_PASS_IN_STACK. */
305 hook_pass_by_reference_must_pass_in_stack (CUMULATIVE_ARGS *c ATTRIBUTE_UNUSED,
306 enum machine_mode mode ATTRIBUTE_UNUSED, const_tree type ATTRIBUTE_UNUSED,
307 bool named_arg ATTRIBUTE_UNUSED)
309 return targetm.calls.must_pass_in_stack (mode, type);
312 /* Return true if a parameter follows callee copies conventions. This
313 version of the hook is true for all named arguments. */
316 hook_callee_copies_named (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
317 enum machine_mode mode ATTRIBUTE_UNUSED,
318 const_tree type ATTRIBUTE_UNUSED, bool named)
323 /* Emit to STREAM the assembler syntax for insn operand X. */
326 default_print_operand (FILE *stream ATTRIBUTE_UNUSED, rtx x ATTRIBUTE_UNUSED,
327 int code ATTRIBUTE_UNUSED)
330 PRINT_OPERAND (stream, x, code);
336 /* Emit to STREAM the assembler syntax for an insn operand whose memory
340 default_print_operand_address (FILE *stream ATTRIBUTE_UNUSED,
341 rtx x ATTRIBUTE_UNUSED)
343 #ifdef PRINT_OPERAND_ADDRESS
344 PRINT_OPERAND_ADDRESS (stream, x);
350 /* Return true if CODE is a valid punctuation character for the
351 `print_operand' hook. */
354 default_print_operand_punct_valid_p (unsigned char code ATTRIBUTE_UNUSED)
356 #ifdef PRINT_OPERAND_PUNCT_VALID_P
357 return PRINT_OPERAND_PUNCT_VALID_P (code);
363 /* The default implementation of TARGET_MANGLE_ASSEMBLER_NAME. */
365 default_mangle_assembler_name (const char *name ATTRIBUTE_UNUSED)
367 const char *skipped = name + (*name == '*' ? 1 : 0);
368 const char *stripped = targetm.strip_name_encoding (skipped);
369 if (*name != '*' && user_label_prefix[0])
370 stripped = ACONCAT ((user_label_prefix, stripped, NULL));
371 return get_identifier (stripped);
374 /* The default implementation of TARGET_ASM_OUTPUT_ADDR_CONST_EXTRA. */
377 default_asm_output_addr_const_extra (FILE *file ATTRIBUTE_UNUSED,
378 rtx x ATTRIBUTE_UNUSED)
380 #ifdef OUTPUT_ADDR_CONST_EXTRA
381 OUTPUT_ADDR_CONST_EXTRA (file, x, fail);
389 /* True if MODE is valid for the target. By "valid", we mean able to
390 be manipulated in non-trivial ways. In particular, this means all
391 the arithmetic is supported.
393 By default we guess this means that any C type is supported. If
394 we can't map the mode back to a type that would be available in C,
395 then reject it. Special case, here, is the double-word arithmetic
396 supported by optabs.c. */
399 default_scalar_mode_supported_p (enum machine_mode mode)
401 int precision = GET_MODE_PRECISION (mode);
403 switch (GET_MODE_CLASS (mode))
405 case MODE_PARTIAL_INT:
407 if (precision == CHAR_TYPE_SIZE)
409 if (precision == SHORT_TYPE_SIZE)
411 if (precision == INT_TYPE_SIZE)
413 if (precision == LONG_TYPE_SIZE)
415 if (precision == LONG_LONG_TYPE_SIZE)
417 if (precision == 2 * BITS_PER_WORD)
422 if (precision == FLOAT_TYPE_SIZE)
424 if (precision == DOUBLE_TYPE_SIZE)
426 if (precision == LONG_DOUBLE_TYPE_SIZE)
430 case MODE_DECIMAL_FLOAT:
442 /* Make some target macros useable by target-independent code. */
444 targhook_words_big_endian (void)
446 return !!WORDS_BIG_ENDIAN;
450 targhook_float_words_big_endian (void)
452 return !!FLOAT_WORDS_BIG_ENDIAN;
455 /* True if the target supports decimal floating point. */
458 default_decimal_float_supported_p (void)
460 return ENABLE_DECIMAL_FLOAT;
463 /* True if the target supports fixed-point arithmetic. */
466 default_fixed_point_supported_p (void)
468 return ENABLE_FIXED_POINT;
471 /* NULL if INSN insn is valid within a low-overhead loop, otherwise returns
474 This function checks whether a given INSN is valid within a low-overhead
475 loop. If INSN is invalid it returns the reason for that, otherwise it
476 returns NULL. A called function may clobber any special registers required
477 for low-overhead looping. Additionally, some targets (eg, PPC) use the count
478 register for branch on table instructions. We reject the doloop pattern in
482 default_invalid_within_doloop (const_rtx insn)
485 return "Function call in loop.";
487 if (JUMP_TABLE_DATA_P (insn))
488 return "Computed branch in the loop.";
493 /* Mapping of builtin functions to vectorized variants. */
496 default_builtin_vectorized_function (tree fndecl ATTRIBUTE_UNUSED,
497 tree type_out ATTRIBUTE_UNUSED,
498 tree type_in ATTRIBUTE_UNUSED)
503 /* Vectorized conversion. */
506 default_builtin_vectorized_conversion (unsigned int code ATTRIBUTE_UNUSED,
507 tree dest_type ATTRIBUTE_UNUSED,
508 tree src_type ATTRIBUTE_UNUSED)
513 /* Default vectorizer cost model values. */
516 default_builtin_vectorization_cost (enum vect_cost_for_stmt type_of_cost,
517 tree vectype ATTRIBUTE_UNUSED,
518 int misalign ATTRIBUTE_UNUSED)
520 switch (type_of_cost)
530 case cond_branch_not_taken:
532 case vec_promote_demote:
536 case unaligned_store:
539 case cond_branch_taken:
550 default_builtin_reciprocal (unsigned int fn ATTRIBUTE_UNUSED,
551 bool md_fn ATTRIBUTE_UNUSED,
552 bool sqrt ATTRIBUTE_UNUSED)
558 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false (
559 CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
560 enum machine_mode mode ATTRIBUTE_UNUSED,
561 const_tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
567 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_true (
568 CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
569 enum machine_mode mode ATTRIBUTE_UNUSED,
570 const_tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
576 hook_int_CUMULATIVE_ARGS_mode_tree_bool_0 (
577 CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
578 enum machine_mode mode ATTRIBUTE_UNUSED,
579 tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
585 default_function_arg_advance (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
586 enum machine_mode mode ATTRIBUTE_UNUSED,
587 const_tree type ATTRIBUTE_UNUSED,
588 bool named ATTRIBUTE_UNUSED)
590 #ifdef FUNCTION_ARG_ADVANCE
591 CUMULATIVE_ARGS args = *ca;
592 FUNCTION_ARG_ADVANCE (args, mode, CONST_CAST_TREE (type), named);
600 default_function_arg (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
601 enum machine_mode mode ATTRIBUTE_UNUSED,
602 const_tree type ATTRIBUTE_UNUSED,
603 bool named ATTRIBUTE_UNUSED)
606 return FUNCTION_ARG (*ca, mode, CONST_CAST_TREE (type), named);
613 default_function_incoming_arg (CUMULATIVE_ARGS *ca ATTRIBUTE_UNUSED,
614 enum machine_mode mode ATTRIBUTE_UNUSED,
615 const_tree type ATTRIBUTE_UNUSED,
616 bool named ATTRIBUTE_UNUSED)
618 #ifdef FUNCTION_INCOMING_ARG
619 return FUNCTION_INCOMING_ARG (*ca, mode, CONST_CAST_TREE (type), named);
626 default_function_arg_boundary (enum machine_mode mode ATTRIBUTE_UNUSED,
627 const_tree type ATTRIBUTE_UNUSED)
629 return PARM_BOUNDARY;
633 hook_void_bitmap (bitmap regs ATTRIBUTE_UNUSED)
638 hook_invalid_arg_for_unprototyped_fn (
639 const_tree typelist ATTRIBUTE_UNUSED,
640 const_tree funcdecl ATTRIBUTE_UNUSED,
641 const_tree val ATTRIBUTE_UNUSED)
646 /* Initialize the stack protection decls. */
648 /* Stack protection related decls living in libgcc. */
649 static GTY(()) tree stack_chk_guard_decl;
652 default_stack_protect_guard (void)
654 tree t = stack_chk_guard_decl;
660 t = build_decl (UNKNOWN_LOCATION,
661 VAR_DECL, get_identifier ("__stack_chk_guard"),
665 DECL_EXTERNAL (t) = 1;
667 TREE_THIS_VOLATILE (t) = 1;
668 DECL_ARTIFICIAL (t) = 1;
669 DECL_IGNORED_P (t) = 1;
671 /* Do not share RTL as the declaration is visible outside of
674 RTX_FLAG (x, used) = 1;
676 stack_chk_guard_decl = t;
682 static GTY(()) tree stack_chk_fail_decl;
685 default_external_stack_protect_fail (void)
687 tree t = stack_chk_fail_decl;
691 t = build_function_type_list (void_type_node, NULL_TREE);
692 t = build_decl (UNKNOWN_LOCATION,
693 FUNCTION_DECL, get_identifier ("__stack_chk_fail"), t);
696 DECL_EXTERNAL (t) = 1;
698 TREE_THIS_VOLATILE (t) = 1;
699 TREE_NOTHROW (t) = 1;
700 DECL_ARTIFICIAL (t) = 1;
701 DECL_IGNORED_P (t) = 1;
702 DECL_VISIBILITY (t) = VISIBILITY_DEFAULT;
703 DECL_VISIBILITY_SPECIFIED (t) = 1;
705 stack_chk_fail_decl = t;
708 return build_call_expr (t, 0);
712 default_hidden_stack_protect_fail (void)
714 #ifndef HAVE_GAS_HIDDEN
715 return default_external_stack_protect_fail ();
717 tree t = stack_chk_fail_decl;
720 return default_external_stack_protect_fail ();
724 t = build_function_type_list (void_type_node, NULL_TREE);
725 t = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL,
726 get_identifier ("__stack_chk_fail_local"), t);
729 DECL_EXTERNAL (t) = 1;
731 TREE_THIS_VOLATILE (t) = 1;
732 TREE_NOTHROW (t) = 1;
733 DECL_ARTIFICIAL (t) = 1;
734 DECL_IGNORED_P (t) = 1;
735 DECL_VISIBILITY_SPECIFIED (t) = 1;
736 DECL_VISIBILITY (t) = VISIBILITY_HIDDEN;
738 stack_chk_fail_decl = t;
741 return build_call_expr (t, 0);
746 hook_bool_const_rtx_commutative_p (const_rtx x,
747 int outer_code ATTRIBUTE_UNUSED)
749 return COMMUTATIVE_P (x);
753 default_function_value (const_tree ret_type ATTRIBUTE_UNUSED,
754 const_tree fn_decl_or_type,
755 bool outgoing ATTRIBUTE_UNUSED)
757 /* The old interface doesn't handle receiving the function type. */
759 && !DECL_P (fn_decl_or_type))
760 fn_decl_or_type = NULL;
762 #ifdef FUNCTION_VALUE
763 return FUNCTION_VALUE (ret_type, fn_decl_or_type);
770 default_libcall_value (enum machine_mode mode ATTRIBUTE_UNUSED,
771 const_rtx fun ATTRIBUTE_UNUSED)
774 return LIBCALL_VALUE (mode);
780 /* The default hook for TARGET_FUNCTION_VALUE_REGNO_P. */
783 default_function_value_regno_p (const unsigned int regno ATTRIBUTE_UNUSED)
785 #ifdef FUNCTION_VALUE_REGNO_P
786 return FUNCTION_VALUE_REGNO_P (regno);
793 default_internal_arg_pointer (void)
795 /* If the reg that the virtual arg pointer will be translated into is
796 not a fixed reg or is the stack pointer, make a copy of the virtual
797 arg pointer, and address parms via the copy. The frame pointer is
798 considered fixed even though it is not marked as such. */
799 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
800 || ! (fixed_regs[ARG_POINTER_REGNUM]
801 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
802 return copy_to_reg (virtual_incoming_args_rtx);
804 return virtual_incoming_args_rtx;
808 default_static_chain (const_tree fndecl, bool incoming_p)
810 if (!DECL_STATIC_CHAIN (fndecl))
815 #ifdef STATIC_CHAIN_INCOMING_REGNUM
816 return gen_rtx_REG (Pmode, STATIC_CHAIN_INCOMING_REGNUM);
820 #ifdef STATIC_CHAIN_REGNUM
821 return gen_rtx_REG (Pmode, STATIC_CHAIN_REGNUM);
825 static bool issued_error;
829 sorry ("nested functions not supported on this target");
832 /* It really doesn't matter what we return here, so long at it
833 doesn't cause the rest of the compiler to crash. */
834 return gen_rtx_MEM (Pmode, stack_pointer_rtx);
839 default_trampoline_init (rtx ARG_UNUSED (m_tramp), tree ARG_UNUSED (t_func),
840 rtx ARG_UNUSED (r_chain))
842 sorry ("nested function trampolines not supported on this target");
846 default_return_pops_args (tree fundecl ATTRIBUTE_UNUSED,
847 tree funtype ATTRIBUTE_UNUSED,
848 int size ATTRIBUTE_UNUSED)
854 default_branch_target_register_class (void)
859 #ifdef IRA_COVER_CLASSES
861 default_ira_cover_classes (void)
863 static reg_class_t classes[] = IRA_COVER_CLASSES;
869 default_secondary_reload (bool in_p ATTRIBUTE_UNUSED, rtx x ATTRIBUTE_UNUSED,
870 reg_class_t reload_class_i ATTRIBUTE_UNUSED,
871 enum machine_mode reload_mode ATTRIBUTE_UNUSED,
872 secondary_reload_info *sri)
874 enum reg_class rclass = NO_REGS;
875 enum reg_class reload_class = (enum reg_class) reload_class_i;
877 if (sri->prev_sri && sri->prev_sri->t_icode != CODE_FOR_nothing)
879 sri->icode = sri->prev_sri->t_icode;
882 #ifdef SECONDARY_INPUT_RELOAD_CLASS
884 rclass = SECONDARY_INPUT_RELOAD_CLASS (reload_class, reload_mode, x);
886 #ifdef SECONDARY_OUTPUT_RELOAD_CLASS
888 rclass = SECONDARY_OUTPUT_RELOAD_CLASS (reload_class, reload_mode, x);
890 if (rclass != NO_REGS)
893 = direct_optab_handler (in_p ? reload_in_optab : reload_out_optab,
896 if (icode != CODE_FOR_nothing
897 && insn_data[(int) icode].operand[in_p].predicate
898 && ! insn_data[(int) icode].operand[in_p].predicate (x, reload_mode))
899 icode = CODE_FOR_nothing;
900 else if (icode != CODE_FOR_nothing)
902 const char *insn_constraint, *scratch_constraint;
903 char insn_letter, scratch_letter;
904 enum reg_class insn_class, scratch_class;
906 gcc_assert (insn_data[(int) icode].n_operands == 3);
907 insn_constraint = insn_data[(int) icode].operand[!in_p].constraint;
908 if (!*insn_constraint)
909 insn_class = ALL_REGS;
914 gcc_assert (*insn_constraint == '=');
917 insn_letter = *insn_constraint;
919 = (insn_letter == 'r' ? GENERAL_REGS
920 : REG_CLASS_FROM_CONSTRAINT ((unsigned char) insn_letter,
922 gcc_assert (insn_class != NO_REGS);
925 scratch_constraint = insn_data[(int) icode].operand[2].constraint;
926 /* The scratch register's constraint must start with "=&",
927 except for an input reload, where only "=" is necessary,
928 and where it might be beneficial to re-use registers from
930 gcc_assert (scratch_constraint[0] == '='
931 && (in_p || scratch_constraint[1] == '&'));
932 scratch_constraint++;
933 if (*scratch_constraint == '&')
934 scratch_constraint++;
935 scratch_letter = *scratch_constraint;
937 = (scratch_letter == 'r' ? GENERAL_REGS
938 : REG_CLASS_FROM_CONSTRAINT ((unsigned char) scratch_letter,
939 scratch_constraint));
941 if (reg_class_subset_p (reload_class, insn_class))
943 gcc_assert (scratch_class == rclass);
950 if (rclass == NO_REGS)
953 sri->t_icode = icode;
959 default_handle_c_option (size_t code ATTRIBUTE_UNUSED,
960 const char *arg ATTRIBUTE_UNUSED,
961 int value ATTRIBUTE_UNUSED)
966 /* By default, if flag_pic is true, then neither local nor global relocs
967 should be placed in readonly memory. */
970 default_reloc_rw_mask (void)
972 return flag_pic ? 3 : 0;
975 /* By default, do no modification. */
976 tree default_mangle_decl_assembler_name (tree decl ATTRIBUTE_UNUSED,
982 /* Default to natural alignment for vector types. */
984 default_vector_alignment (const_tree type)
986 return tree_low_cst (TYPE_SIZE (type), 0);
990 default_builtin_vector_alignment_reachable (const_tree type, bool is_packed)
995 /* Assuming that types whose size is > pointer-size are not guaranteed to be
996 naturally aligned. */
997 if (tree_int_cst_compare (TYPE_SIZE (type), bitsize_int (POINTER_SIZE)) > 0)
1000 /* Assuming that types whose size is <= pointer-size
1001 are naturally aligned. */
1005 /* By default, assume that a target supports any factor of misalignment
1006 memory access if it supports movmisalign patten.
1007 is_packed is true if the memory access is defined in a packed struct. */
1009 default_builtin_support_vector_misalignment (enum machine_mode mode,
1017 if (optab_handler (movmisalign_optab, mode) != CODE_FOR_nothing)
1022 /* By default, only attempt to parallelize bitwise operations, and
1023 possibly adds/subtracts using bit-twiddling. */
1026 default_preferred_simd_mode (enum machine_mode mode ATTRIBUTE_UNUSED)
1031 /* By default only the size derived from the preferred vector mode
1035 default_autovectorize_vector_sizes (void)
1040 /* Determine whether or not a pointer mode is valid. Assume defaults
1041 of ptr_mode or Pmode - can be overridden. */
1043 default_valid_pointer_mode (enum machine_mode mode)
1045 return (mode == ptr_mode || mode == Pmode);
1048 /* Determine whether the memory reference specified by REF may alias
1049 the C libraries errno location. */
1051 default_ref_may_alias_errno (ao_ref *ref)
1053 tree base = ao_ref_base (ref);
1054 /* The default implementation assumes the errno location is
1055 a declaration of type int or is always accessed via a
1056 pointer to int. We assume that accesses to errno are
1057 not deliberately obfuscated (even in conforming ways). */
1058 if (TYPE_UNSIGNED (TREE_TYPE (base))
1059 || TYPE_MODE (TREE_TYPE (base)) != TYPE_MODE (integer_type_node))
1061 /* The default implementation assumes an errno location
1062 declaration is never defined in the current compilation unit. */
1064 && !TREE_STATIC (base))
1066 else if (TREE_CODE (base) == MEM_REF
1067 && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME)
1069 struct ptr_info_def *pi = SSA_NAME_PTR_INFO (TREE_OPERAND (base, 0));
1070 return !pi || pi->pt.anything || pi->pt.nonlocal;
1075 /* Return the mode for a pointer to a given ADDRSPACE, defaulting to ptr_mode
1076 for the generic address space only. */
1079 default_addr_space_pointer_mode (addr_space_t addrspace ATTRIBUTE_UNUSED)
1081 gcc_assert (ADDR_SPACE_GENERIC_P (addrspace));
1085 /* Return the mode for an address in a given ADDRSPACE, defaulting to Pmode
1086 for the generic address space only. */
1089 default_addr_space_address_mode (addr_space_t addrspace ATTRIBUTE_UNUSED)
1091 gcc_assert (ADDR_SPACE_GENERIC_P (addrspace));
1095 /* Named address space version of valid_pointer_mode. */
1098 default_addr_space_valid_pointer_mode (enum machine_mode mode, addr_space_t as)
1100 if (!ADDR_SPACE_GENERIC_P (as))
1101 return (mode == targetm.addr_space.pointer_mode (as)
1102 || mode == targetm.addr_space.address_mode (as));
1104 return targetm.valid_pointer_mode (mode);
1107 /* Some places still assume that all pointer or address modes are the
1108 standard Pmode and ptr_mode. These optimizations become invalid if
1109 the target actually supports multiple different modes. For now,
1110 we disable such optimizations on such targets, using this function. */
1113 target_default_pointer_address_modes_p (void)
1115 if (targetm.addr_space.address_mode != default_addr_space_address_mode)
1117 if (targetm.addr_space.pointer_mode != default_addr_space_pointer_mode)
1123 /* Named address space version of legitimate_address_p. */
1126 default_addr_space_legitimate_address_p (enum machine_mode mode, rtx mem,
1127 bool strict, addr_space_t as)
1129 if (!ADDR_SPACE_GENERIC_P (as))
1132 return targetm.legitimate_address_p (mode, mem, strict);
1135 /* Named address space version of LEGITIMIZE_ADDRESS. */
1138 default_addr_space_legitimize_address (rtx x, rtx oldx,
1139 enum machine_mode mode, addr_space_t as)
1141 if (!ADDR_SPACE_GENERIC_P (as))
1144 return targetm.legitimize_address (x, oldx, mode);
1147 /* The default hook for determining if one named address space is a subset of
1148 another and to return which address space to use as the common address
1152 default_addr_space_subset_p (addr_space_t subset, addr_space_t superset)
1154 return (subset == superset);
1157 /* The default hook for TARGET_ADDR_SPACE_CONVERT. This hook should never be
1158 called for targets with only a generic address space. */
1161 default_addr_space_convert (rtx op ATTRIBUTE_UNUSED,
1162 tree from_type ATTRIBUTE_UNUSED,
1163 tree to_type ATTRIBUTE_UNUSED)
1169 default_hard_regno_scratch_ok (unsigned int regno ATTRIBUTE_UNUSED)
1174 /* The default implementation of TARGET_MODE_DEPENDENT_ADDRESS_P. */
1177 default_mode_dependent_address_p (const_rtx addr ATTRIBUTE_UNUSED)
1179 #ifdef GO_IF_MODE_DEPENDENT_ADDRESS
1181 GO_IF_MODE_DEPENDENT_ADDRESS (CONST_CAST_RTX (addr), win);
1183 /* Label `win' might (not) be used via GO_IF_MODE_DEPENDENT_ADDRESS. */
1184 win: ATTRIBUTE_UNUSED_LABEL
1195 default_target_option_valid_attribute_p (tree ARG_UNUSED (fndecl),
1196 tree ARG_UNUSED (name),
1197 tree ARG_UNUSED (args),
1198 int ARG_UNUSED (flags))
1200 warning (OPT_Wattributes,
1201 "target attribute is not supported on this machine");
1207 default_target_option_pragma_parse (tree ARG_UNUSED (args),
1208 tree ARG_UNUSED (pop_target))
1210 warning (OPT_Wpragmas,
1211 "#pragma GCC target is not supported for this machine");
1217 default_target_can_inline_p (tree caller, tree callee)
1220 tree callee_opts = DECL_FUNCTION_SPECIFIC_TARGET (callee);
1221 tree caller_opts = DECL_FUNCTION_SPECIFIC_TARGET (caller);
1223 /* If callee has no option attributes, then it is ok to inline */
1227 /* If caller has no option attributes, but callee does then it is not ok to
1229 else if (!caller_opts)
1232 /* If both caller and callee have attributes, assume that if the pointer is
1233 different, the the two functions have different target options since
1234 build_target_option_node uses a hash table for the options. */
1236 ret = (callee_opts == caller_opts);
1242 # define HAVE_casesi 0
1245 /* If the machine does not have a case insn that compares the bounds,
1246 this means extra overhead for dispatch tables, which raises the
1247 threshold for using them. */
1249 unsigned int default_case_values_threshold (void)
1251 return (HAVE_casesi ? 4 : 5);
1255 default_have_conditional_execution (void)
1257 #ifdef HAVE_conditional_execution
1258 return HAVE_conditional_execution;
1264 /* Compute cost of moving registers to/from memory. */
1267 default_memory_move_cost (enum machine_mode mode ATTRIBUTE_UNUSED,
1268 reg_class_t rclass ATTRIBUTE_UNUSED,
1269 bool in ATTRIBUTE_UNUSED)
1271 #ifndef MEMORY_MOVE_COST
1272 return (4 + memory_move_secondary_cost (mode, (enum reg_class) rclass, in));
1274 return MEMORY_MOVE_COST (mode, (enum reg_class) rclass, in);
1278 /* Compute cost of moving data from a register of class FROM to one of
1282 default_register_move_cost (enum machine_mode mode ATTRIBUTE_UNUSED,
1283 reg_class_t from ATTRIBUTE_UNUSED,
1284 reg_class_t to ATTRIBUTE_UNUSED)
1286 #ifndef REGISTER_MOVE_COST
1289 return REGISTER_MOVE_COST (mode, (enum reg_class) from, (enum reg_class) to);
1294 default_profile_before_prologue (void)
1296 #ifdef PROFILE_BEFORE_PROLOGUE
1303 /* The default implementation of TARGET_PREFERRED_RELOAD_CLASS. */
1306 default_preferred_reload_class (rtx x ATTRIBUTE_UNUSED,
1309 #ifdef PREFERRED_RELOAD_CLASS
1310 return (reg_class_t) PREFERRED_RELOAD_CLASS (x, (enum reg_class) rclass);
1316 /* The default implementation of TARGET_OUTPUT_PREFERRED_RELOAD_CLASS. */
1319 default_preferred_output_reload_class (rtx x ATTRIBUTE_UNUSED,
1322 #ifdef PREFERRED_OUTPUT_RELOAD_CLASS
1323 return PREFERRED_OUTPUT_RELOAD_CLASS (x, (enum reg_class) rclass);
1329 /* The default implementation of TARGET_PREFERRED_RENAME_CLASS. */
1331 default_preferred_rename_class (reg_class_t rclass ATTRIBUTE_UNUSED)
1336 /* The default implementation of TARGET_CLASS_LIKELY_SPILLED_P. */
1339 default_class_likely_spilled_p (reg_class_t rclass)
1341 return (reg_class_size[(int) rclass] == 1);
1344 /* Determine the debugging unwind mechanism for the target. */
1346 enum unwind_info_type
1347 default_debug_unwind_info (void)
1349 /* If the target wants to force the use of dwarf2 unwind info, let it. */
1350 /* ??? Change all users to the hook, then poison this. */
1351 #ifdef DWARF2_FRAME_INFO
1352 if (DWARF2_FRAME_INFO)
1356 /* Otherwise, only turn it on if dwarf2 debugging is enabled. */
1357 #ifdef DWARF2_DEBUGGING_INFO
1358 if (write_symbols == DWARF2_DEBUG || write_symbols == VMS_AND_DWARF2_DEBUG)
1365 /* Determine the exception handling mechanism for the target. */
1367 enum unwind_info_type
1368 default_except_unwind_info (struct gcc_options *opts ATTRIBUTE_UNUSED)
1370 /* Obey the configure switch to turn on sjlj exceptions. */
1371 #ifdef CONFIG_SJLJ_EXCEPTIONS
1372 if (CONFIG_SJLJ_EXCEPTIONS)
1376 /* ??? Change all users to the hook, then poison this. */
1377 #ifdef DWARF2_UNWIND_INFO
1378 if (DWARF2_UNWIND_INFO)
1385 /* To be used by targets that force dwarf2 unwind enabled. */
1387 enum unwind_info_type
1388 dwarf2_except_unwind_info (struct gcc_options *opts ATTRIBUTE_UNUSED)
1390 /* Obey the configure switch to turn on sjlj exceptions. */
1391 #ifdef CONFIG_SJLJ_EXCEPTIONS
1392 if (CONFIG_SJLJ_EXCEPTIONS)
1399 /* To be used by targets that force sjlj unwind enabled. */
1401 enum unwind_info_type
1402 sjlj_except_unwind_info (struct gcc_options *opts ATTRIBUTE_UNUSED)
1407 /* To be used by targets where reg_raw_mode doesn't return the right
1408 mode for registers used in apply_builtin_return and apply_builtin_arg. */
1411 default_get_reg_raw_mode(int regno)
1413 return reg_raw_mode[regno];
1416 /* Return true if the state of option OPTION should be stored in PCH files
1417 and checked by default_pch_valid_p. Store the option's current state
1421 option_affects_pch_p (int option, struct cl_option_state *state)
1423 if ((cl_options[option].flags & CL_TARGET) == 0)
1425 if (option_flag_var (option, &global_options) == &target_flags)
1426 if (targetm.check_pch_target_flags)
1428 return get_option_state (&global_options, option, state);
1431 /* Default version of get_pch_validity.
1432 By default, every flag difference is fatal; that will be mostly right for
1433 most targets, but completely right for very few. */
1436 default_get_pch_validity (size_t *sz)
1438 struct cl_option_state state;
1443 if (targetm.check_pch_target_flags)
1444 *sz += sizeof (target_flags);
1445 for (i = 0; i < cl_options_count; i++)
1446 if (option_affects_pch_p (i, &state))
1449 result = r = XNEWVEC (char, *sz);
1453 if (targetm.check_pch_target_flags)
1455 memcpy (r, &target_flags, sizeof (target_flags));
1456 r += sizeof (target_flags);
1459 for (i = 0; i < cl_options_count; i++)
1460 if (option_affects_pch_p (i, &state))
1462 memcpy (r, state.data, state.size);
1469 /* Return a message which says that a PCH file was created with a different
1470 setting of OPTION. */
1473 pch_option_mismatch (const char *option)
1477 asprintf (&r, _("created and used with differing settings of '%s'"), option);
1479 return _("out of memory");
1483 /* Default version of pch_valid_p. */
1486 default_pch_valid_p (const void *data_p, size_t len)
1488 struct cl_option_state state;
1489 const char *data = (const char *)data_p;
1492 /* -fpic and -fpie also usually make a PCH invalid. */
1493 if (data[0] != flag_pic)
1494 return _("created and used with different settings of -fpic");
1495 if (data[1] != flag_pie)
1496 return _("created and used with different settings of -fpie");
1499 /* Check target_flags. */
1500 if (targetm.check_pch_target_flags)
1505 memcpy (&tf, data, sizeof (target_flags));
1506 data += sizeof (target_flags);
1507 len -= sizeof (target_flags);
1508 r = targetm.check_pch_target_flags (tf);
1513 for (i = 0; i < cl_options_count; i++)
1514 if (option_affects_pch_p (i, &state))
1516 if (memcmp (data, state.data, state.size) != 0)
1517 return pch_option_mismatch (cl_options[i].opt_text);
1525 const struct default_options empty_optimization_table[] =
1527 { OPT_LEVELS_NONE, 0, NULL, 0 }
1530 #include "gt-targhooks.h"