1 /* Default target hook functions.
2 Copyright (C) 2003-2013 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
20 /* The migration of target macros to target hooks works as follows:
22 1. Create a target hook that uses the existing target macros to
23 implement the same functionality.
25 2. Convert all the MI files to use the hook instead of the macro.
27 3. Repeat for a majority of the remaining target macros. This will
30 4. Tell target maintainers to start migrating.
32 5. Eventually convert the backends to override the hook instead of
33 defining the macros. This will take some time too.
35 6. TBD when, poison the macros. Unmigrated targets will break at
38 Note that we expect steps 1-3 to be done by the people that
39 understand what the MI does with each macro, and step 5 to be done
40 by the target maintainers for their respective targets.
42 Note that steps 1 and 2 don't have to be done together, but no
43 target can override the new hook until step 2 is complete for it.
45 Once the macros are poisoned, we will revert to the old migration
46 rules - migrate the macro, callers, and targets all at once. This
47 comment can thus be removed at that point. */
51 #include "coretypes.h"
58 #include "diagnostic-core.h"
62 #include "target-def.h"
64 #include "hard-reg-set.h"
72 #include "tree-ssanames.h"
73 #include "tree-ssa-alias.h"
74 #include "insn-codes.h"
78 default_legitimate_address_p (enum machine_mode mode ATTRIBUTE_UNUSED,
79 rtx addr ATTRIBUTE_UNUSED,
80 bool strict ATTRIBUTE_UNUSED)
82 #ifdef GO_IF_LEGITIMATE_ADDRESS
83 /* Defer to the old implementation using a goto. */
85 return strict_memory_address_p (mode, addr);
87 return memory_address_p (mode, addr);
94 default_external_libcall (rtx fun ATTRIBUTE_UNUSED)
96 #ifdef ASM_OUTPUT_EXTERNAL_LIBCALL
97 ASM_OUTPUT_EXTERNAL_LIBCALL (asm_out_file, fun);
102 default_unspec_may_trap_p (const_rtx x, unsigned flags)
106 /* Any floating arithmetic may trap. */
107 if ((SCALAR_FLOAT_MODE_P (GET_MODE (x)) && flag_trapping_math))
110 for (i = 0; i < XVECLEN (x, 0); ++i)
112 if (may_trap_p_1 (XVECEXP (x, 0, i), flags))
120 default_promote_function_mode (const_tree type ATTRIBUTE_UNUSED,
121 enum machine_mode mode,
122 int *punsignedp ATTRIBUTE_UNUSED,
123 const_tree funtype ATTRIBUTE_UNUSED,
124 int for_return ATTRIBUTE_UNUSED)
126 if (type != NULL_TREE && for_return == 2)
127 return promote_mode (type, mode, punsignedp);
132 default_promote_function_mode_always_promote (const_tree type,
133 enum machine_mode mode,
135 const_tree funtype ATTRIBUTE_UNUSED,
136 int for_return ATTRIBUTE_UNUSED)
138 return promote_mode (type, mode, punsignedp);
143 default_cc_modes_compatible (enum machine_mode m1, enum machine_mode m2)
151 default_return_in_memory (const_tree type,
152 const_tree fntype ATTRIBUTE_UNUSED)
154 return (TYPE_MODE (type) == BLKmode);
158 default_legitimize_address (rtx x, rtx orig_x ATTRIBUTE_UNUSED,
159 enum machine_mode mode ATTRIBUTE_UNUSED)
165 default_expand_builtin_saveregs (void)
167 error ("__builtin_saveregs not supported by this target");
172 default_setup_incoming_varargs (cumulative_args_t ca ATTRIBUTE_UNUSED,
173 enum machine_mode mode ATTRIBUTE_UNUSED,
174 tree type ATTRIBUTE_UNUSED,
175 int *pretend_arg_size ATTRIBUTE_UNUSED,
176 int second_time ATTRIBUTE_UNUSED)
180 /* The default implementation of TARGET_BUILTIN_SETJMP_FRAME_VALUE. */
183 default_builtin_setjmp_frame_value (void)
185 return virtual_stack_vars_rtx;
188 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns false. */
191 hook_bool_CUMULATIVE_ARGS_false (cumulative_args_t ca ATTRIBUTE_UNUSED)
197 default_pretend_outgoing_varargs_named (cumulative_args_t ca ATTRIBUTE_UNUSED)
199 return (targetm.calls.setup_incoming_varargs
200 != default_setup_incoming_varargs);
204 default_eh_return_filter_mode (void)
206 return targetm.unwind_word_mode ();
210 default_libgcc_cmp_return_mode (void)
216 default_libgcc_shift_count_mode (void)
222 default_unwind_word_mode (void)
227 /* The default implementation of TARGET_SHIFT_TRUNCATION_MASK. */
229 unsigned HOST_WIDE_INT
230 default_shift_truncation_mask (enum machine_mode mode)
232 return SHIFT_COUNT_TRUNCATED ? GET_MODE_BITSIZE (mode) - 1 : 0;
235 /* The default implementation of TARGET_MIN_DIVISIONS_FOR_RECIP_MUL. */
238 default_min_divisions_for_recip_mul (enum machine_mode mode ATTRIBUTE_UNUSED)
240 return have_insn_for (DIV, mode) ? 3 : 2;
243 /* The default implementation of TARGET_MODE_REP_EXTENDED. */
246 default_mode_rep_extended (enum machine_mode mode ATTRIBUTE_UNUSED,
247 enum machine_mode mode_rep ATTRIBUTE_UNUSED)
252 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns true. */
255 hook_bool_CUMULATIVE_ARGS_true (cumulative_args_t a ATTRIBUTE_UNUSED)
260 /* Return machine mode for non-standard suffix
261 or VOIDmode if non-standard suffixes are unsupported. */
263 default_mode_for_suffix (char suffix ATTRIBUTE_UNUSED)
268 /* The generic C++ ABI specifies this is a 64-bit value. */
270 default_cxx_guard_type (void)
272 return long_long_integer_type_node;
276 /* Returns the size of the cookie to use when allocating an array
277 whose elements have the indicated TYPE. Assumes that it is already
278 known that a cookie is needed. */
281 default_cxx_get_cookie_size (tree type)
285 /* We need to allocate an additional max (sizeof (size_t), alignof
286 (true_type)) bytes. */
290 sizetype_size = size_in_bytes (sizetype);
291 type_align = size_int (TYPE_ALIGN_UNIT (type));
292 if (INT_CST_LT_UNSIGNED (type_align, sizetype_size))
293 cookie_size = sizetype_size;
295 cookie_size = type_align;
300 /* Return true if a parameter must be passed by reference. This version
301 of the TARGET_PASS_BY_REFERENCE hook uses just MUST_PASS_IN_STACK. */
304 hook_pass_by_reference_must_pass_in_stack (cumulative_args_t c ATTRIBUTE_UNUSED,
305 enum machine_mode mode ATTRIBUTE_UNUSED, const_tree type ATTRIBUTE_UNUSED,
306 bool named_arg ATTRIBUTE_UNUSED)
308 return targetm.calls.must_pass_in_stack (mode, type);
311 /* Return true if a parameter follows callee copies conventions. This
312 version of the hook is true for all named arguments. */
315 hook_callee_copies_named (cumulative_args_t ca ATTRIBUTE_UNUSED,
316 enum machine_mode mode ATTRIBUTE_UNUSED,
317 const_tree type ATTRIBUTE_UNUSED, bool named)
322 /* Emit to STREAM the assembler syntax for insn operand X. */
325 default_print_operand (FILE *stream ATTRIBUTE_UNUSED, rtx x ATTRIBUTE_UNUSED,
326 int code ATTRIBUTE_UNUSED)
329 PRINT_OPERAND (stream, x, code);
335 /* Emit to STREAM the assembler syntax for an insn operand whose memory
339 default_print_operand_address (FILE *stream ATTRIBUTE_UNUSED,
340 rtx x ATTRIBUTE_UNUSED)
342 #ifdef PRINT_OPERAND_ADDRESS
343 PRINT_OPERAND_ADDRESS (stream, x);
349 /* Return true if CODE is a valid punctuation character for the
350 `print_operand' hook. */
353 default_print_operand_punct_valid_p (unsigned char code ATTRIBUTE_UNUSED)
355 #ifdef PRINT_OPERAND_PUNCT_VALID_P
356 return PRINT_OPERAND_PUNCT_VALID_P (code);
362 /* The default implementation of TARGET_MANGLE_ASSEMBLER_NAME. */
364 default_mangle_assembler_name (const char *name ATTRIBUTE_UNUSED)
366 const char *skipped = name + (*name == '*' ? 1 : 0);
367 const char *stripped = targetm.strip_name_encoding (skipped);
368 if (*name != '*' && user_label_prefix[0])
369 stripped = ACONCAT ((user_label_prefix, stripped, NULL));
370 return get_identifier (stripped);
373 /* True if MODE is valid for the target. By "valid", we mean able to
374 be manipulated in non-trivial ways. In particular, this means all
375 the arithmetic is supported.
377 By default we guess this means that any C type is supported. If
378 we can't map the mode back to a type that would be available in C,
379 then reject it. Special case, here, is the double-word arithmetic
380 supported by optabs.c. */
383 default_scalar_mode_supported_p (enum machine_mode mode)
385 int precision = GET_MODE_PRECISION (mode);
387 switch (GET_MODE_CLASS (mode))
389 case MODE_PARTIAL_INT:
391 if (precision == CHAR_TYPE_SIZE)
393 if (precision == SHORT_TYPE_SIZE)
395 if (precision == INT_TYPE_SIZE)
397 if (precision == LONG_TYPE_SIZE)
399 if (precision == LONG_LONG_TYPE_SIZE)
401 if (precision == 2 * BITS_PER_WORD)
406 if (precision == FLOAT_TYPE_SIZE)
408 if (precision == DOUBLE_TYPE_SIZE)
410 if (precision == LONG_DOUBLE_TYPE_SIZE)
414 case MODE_DECIMAL_FLOAT:
426 /* Make some target macros useable by target-independent code. */
428 targhook_words_big_endian (void)
430 return !!WORDS_BIG_ENDIAN;
434 targhook_float_words_big_endian (void)
436 return !!FLOAT_WORDS_BIG_ENDIAN;
439 /* True if the target supports floating-point exceptions and rounding
443 default_float_exceptions_rounding_supported_p (void)
452 /* True if the target supports decimal floating point. */
455 default_decimal_float_supported_p (void)
457 return ENABLE_DECIMAL_FLOAT;
460 /* True if the target supports fixed-point arithmetic. */
463 default_fixed_point_supported_p (void)
465 return ENABLE_FIXED_POINT;
468 /* True if the target supports GNU indirect functions. */
471 default_has_ifunc_p (void)
473 return HAVE_GNU_INDIRECT_FUNCTION;
476 /* NULL if INSN insn is valid within a low-overhead loop, otherwise returns
479 This function checks whether a given INSN is valid within a low-overhead
480 loop. If INSN is invalid it returns the reason for that, otherwise it
481 returns NULL. A called function may clobber any special registers required
482 for low-overhead looping. Additionally, some targets (eg, PPC) use the count
483 register for branch on table instructions. We reject the doloop pattern in
487 default_invalid_within_doloop (const_rtx insn)
490 return "Function call in loop.";
492 if (tablejump_p (insn, NULL, NULL) || computed_jump_p (insn))
493 return "Computed branch in the loop.";
498 /* Mapping of builtin functions to vectorized variants. */
501 default_builtin_vectorized_function (tree fndecl ATTRIBUTE_UNUSED,
502 tree type_out ATTRIBUTE_UNUSED,
503 tree type_in ATTRIBUTE_UNUSED)
508 /* Vectorized conversion. */
511 default_builtin_vectorized_conversion (unsigned int code ATTRIBUTE_UNUSED,
512 tree dest_type ATTRIBUTE_UNUSED,
513 tree src_type ATTRIBUTE_UNUSED)
518 /* Default vectorizer cost model values. */
521 default_builtin_vectorization_cost (enum vect_cost_for_stmt type_of_cost,
523 int misalign ATTRIBUTE_UNUSED)
527 switch (type_of_cost)
537 case cond_branch_not_taken:
539 case vec_promote_demote:
543 case unaligned_store:
546 case cond_branch_taken:
550 elements = TYPE_VECTOR_SUBPARTS (vectype);
551 return elements / 2 + 1;
561 default_builtin_reciprocal (unsigned int fn ATTRIBUTE_UNUSED,
562 bool md_fn ATTRIBUTE_UNUSED,
563 bool sqrt ATTRIBUTE_UNUSED)
569 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_false (
570 cumulative_args_t ca ATTRIBUTE_UNUSED,
571 enum machine_mode mode ATTRIBUTE_UNUSED,
572 const_tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
578 hook_bool_CUMULATIVE_ARGS_mode_tree_bool_true (
579 cumulative_args_t ca ATTRIBUTE_UNUSED,
580 enum machine_mode mode ATTRIBUTE_UNUSED,
581 const_tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
587 hook_int_CUMULATIVE_ARGS_mode_tree_bool_0 (
588 cumulative_args_t ca ATTRIBUTE_UNUSED,
589 enum machine_mode mode ATTRIBUTE_UNUSED,
590 tree type ATTRIBUTE_UNUSED, bool named ATTRIBUTE_UNUSED)
596 default_function_arg_advance (cumulative_args_t ca ATTRIBUTE_UNUSED,
597 enum machine_mode mode ATTRIBUTE_UNUSED,
598 const_tree type ATTRIBUTE_UNUSED,
599 bool named ATTRIBUTE_UNUSED)
605 default_function_arg (cumulative_args_t ca ATTRIBUTE_UNUSED,
606 enum machine_mode mode ATTRIBUTE_UNUSED,
607 const_tree type ATTRIBUTE_UNUSED,
608 bool named ATTRIBUTE_UNUSED)
614 default_function_incoming_arg (cumulative_args_t ca ATTRIBUTE_UNUSED,
615 enum machine_mode mode ATTRIBUTE_UNUSED,
616 const_tree type ATTRIBUTE_UNUSED,
617 bool named ATTRIBUTE_UNUSED)
623 default_function_arg_boundary (enum machine_mode mode ATTRIBUTE_UNUSED,
624 const_tree type ATTRIBUTE_UNUSED)
626 return PARM_BOUNDARY;
630 default_function_arg_round_boundary (enum machine_mode mode ATTRIBUTE_UNUSED,
631 const_tree type ATTRIBUTE_UNUSED)
633 return PARM_BOUNDARY;
637 hook_void_bitmap (bitmap regs ATTRIBUTE_UNUSED)
642 hook_invalid_arg_for_unprototyped_fn (
643 const_tree typelist ATTRIBUTE_UNUSED,
644 const_tree funcdecl ATTRIBUTE_UNUSED,
645 const_tree val ATTRIBUTE_UNUSED)
650 /* Initialize the stack protection decls. */
652 /* Stack protection related decls living in libgcc. */
653 static GTY(()) tree stack_chk_guard_decl;
656 default_stack_protect_guard (void)
658 tree t = stack_chk_guard_decl;
664 t = build_decl (UNKNOWN_LOCATION,
665 VAR_DECL, get_identifier ("__stack_chk_guard"),
669 DECL_EXTERNAL (t) = 1;
671 TREE_THIS_VOLATILE (t) = 1;
672 DECL_ARTIFICIAL (t) = 1;
673 DECL_IGNORED_P (t) = 1;
675 /* Do not share RTL as the declaration is visible outside of
678 RTX_FLAG (x, used) = 1;
680 stack_chk_guard_decl = t;
686 static GTY(()) tree stack_chk_fail_decl;
689 default_external_stack_protect_fail (void)
691 tree t = stack_chk_fail_decl;
695 t = build_function_type_list (void_type_node, NULL_TREE);
696 t = build_decl (UNKNOWN_LOCATION,
697 FUNCTION_DECL, get_identifier ("__stack_chk_fail"), t);
700 DECL_EXTERNAL (t) = 1;
702 TREE_THIS_VOLATILE (t) = 1;
703 TREE_NOTHROW (t) = 1;
704 DECL_ARTIFICIAL (t) = 1;
705 DECL_IGNORED_P (t) = 1;
706 DECL_VISIBILITY (t) = VISIBILITY_DEFAULT;
707 DECL_VISIBILITY_SPECIFIED (t) = 1;
709 stack_chk_fail_decl = t;
712 return build_call_expr (t, 0);
716 default_hidden_stack_protect_fail (void)
718 #ifndef HAVE_GAS_HIDDEN
719 return default_external_stack_protect_fail ();
721 tree t = stack_chk_fail_decl;
724 return default_external_stack_protect_fail ();
728 t = build_function_type_list (void_type_node, NULL_TREE);
729 t = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL,
730 get_identifier ("__stack_chk_fail_local"), t);
733 DECL_EXTERNAL (t) = 1;
735 TREE_THIS_VOLATILE (t) = 1;
736 TREE_NOTHROW (t) = 1;
737 DECL_ARTIFICIAL (t) = 1;
738 DECL_IGNORED_P (t) = 1;
739 DECL_VISIBILITY_SPECIFIED (t) = 1;
740 DECL_VISIBILITY (t) = VISIBILITY_HIDDEN;
742 stack_chk_fail_decl = t;
745 return build_call_expr (t, 0);
750 hook_bool_const_rtx_commutative_p (const_rtx x,
751 int outer_code ATTRIBUTE_UNUSED)
753 return COMMUTATIVE_P (x);
757 default_function_value (const_tree ret_type ATTRIBUTE_UNUSED,
758 const_tree fn_decl_or_type,
759 bool outgoing ATTRIBUTE_UNUSED)
761 /* The old interface doesn't handle receiving the function type. */
763 && !DECL_P (fn_decl_or_type))
764 fn_decl_or_type = NULL;
766 #ifdef FUNCTION_VALUE
767 return FUNCTION_VALUE (ret_type, fn_decl_or_type);
774 default_libcall_value (enum machine_mode mode ATTRIBUTE_UNUSED,
775 const_rtx fun ATTRIBUTE_UNUSED)
778 return LIBCALL_VALUE (mode);
784 /* The default hook for TARGET_FUNCTION_VALUE_REGNO_P. */
787 default_function_value_regno_p (const unsigned int regno ATTRIBUTE_UNUSED)
789 #ifdef FUNCTION_VALUE_REGNO_P
790 return FUNCTION_VALUE_REGNO_P (regno);
797 default_internal_arg_pointer (void)
799 /* If the reg that the virtual arg pointer will be translated into is
800 not a fixed reg or is the stack pointer, make a copy of the virtual
801 arg pointer, and address parms via the copy. The frame pointer is
802 considered fixed even though it is not marked as such. */
803 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
804 || ! (fixed_regs[ARG_POINTER_REGNUM]
805 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
806 return copy_to_reg (virtual_incoming_args_rtx);
808 return virtual_incoming_args_rtx;
812 default_static_chain (const_tree fndecl, bool incoming_p)
814 if (!DECL_STATIC_CHAIN (fndecl))
819 #ifdef STATIC_CHAIN_INCOMING_REGNUM
820 return gen_rtx_REG (Pmode, STATIC_CHAIN_INCOMING_REGNUM);
824 #ifdef STATIC_CHAIN_REGNUM
825 return gen_rtx_REG (Pmode, STATIC_CHAIN_REGNUM);
829 static bool issued_error;
833 sorry ("nested functions not supported on this target");
836 /* It really doesn't matter what we return here, so long at it
837 doesn't cause the rest of the compiler to crash. */
838 return gen_rtx_MEM (Pmode, stack_pointer_rtx);
843 default_trampoline_init (rtx ARG_UNUSED (m_tramp), tree ARG_UNUSED (t_func),
844 rtx ARG_UNUSED (r_chain))
846 sorry ("nested function trampolines not supported on this target");
850 default_return_pops_args (tree fundecl ATTRIBUTE_UNUSED,
851 tree funtype ATTRIBUTE_UNUSED,
852 int size ATTRIBUTE_UNUSED)
858 default_branch_target_register_class (void)
870 default_register_priority (int hard_regno ATTRIBUTE_UNUSED)
876 default_register_usage_leveling_p (void)
882 default_different_addr_displacement_p (void)
888 default_secondary_reload (bool in_p ATTRIBUTE_UNUSED, rtx x ATTRIBUTE_UNUSED,
889 reg_class_t reload_class_i ATTRIBUTE_UNUSED,
890 enum machine_mode reload_mode ATTRIBUTE_UNUSED,
891 secondary_reload_info *sri)
893 enum reg_class rclass = NO_REGS;
894 enum reg_class reload_class = (enum reg_class) reload_class_i;
896 if (sri->prev_sri && sri->prev_sri->t_icode != CODE_FOR_nothing)
898 sri->icode = sri->prev_sri->t_icode;
901 #ifdef SECONDARY_INPUT_RELOAD_CLASS
903 rclass = SECONDARY_INPUT_RELOAD_CLASS (reload_class, reload_mode, x);
905 #ifdef SECONDARY_OUTPUT_RELOAD_CLASS
907 rclass = SECONDARY_OUTPUT_RELOAD_CLASS (reload_class, reload_mode, x);
909 if (rclass != NO_REGS)
912 = direct_optab_handler (in_p ? reload_in_optab : reload_out_optab,
915 if (icode != CODE_FOR_nothing
916 && !insn_operand_matches (icode, in_p, x))
917 icode = CODE_FOR_nothing;
918 else if (icode != CODE_FOR_nothing)
920 const char *insn_constraint, *scratch_constraint;
921 char insn_letter, scratch_letter;
922 enum reg_class insn_class, scratch_class;
924 gcc_assert (insn_data[(int) icode].n_operands == 3);
925 insn_constraint = insn_data[(int) icode].operand[!in_p].constraint;
926 if (!*insn_constraint)
927 insn_class = ALL_REGS;
932 gcc_assert (*insn_constraint == '=');
935 insn_letter = *insn_constraint;
937 = (insn_letter == 'r' ? GENERAL_REGS
938 : REG_CLASS_FROM_CONSTRAINT ((unsigned char) insn_letter,
940 gcc_assert (insn_class != NO_REGS);
943 scratch_constraint = insn_data[(int) icode].operand[2].constraint;
944 /* The scratch register's constraint must start with "=&",
945 except for an input reload, where only "=" is necessary,
946 and where it might be beneficial to re-use registers from
948 gcc_assert (scratch_constraint[0] == '='
949 && (in_p || scratch_constraint[1] == '&'));
950 scratch_constraint++;
951 if (*scratch_constraint == '&')
952 scratch_constraint++;
953 scratch_letter = *scratch_constraint;
955 = (scratch_letter == 'r' ? GENERAL_REGS
956 : REG_CLASS_FROM_CONSTRAINT ((unsigned char) scratch_letter,
957 scratch_constraint));
959 if (reg_class_subset_p (reload_class, insn_class))
961 gcc_assert (scratch_class == rclass);
968 if (rclass == NO_REGS)
971 sri->t_icode = icode;
976 /* By default, if flag_pic is true, then neither local nor global relocs
977 should be placed in readonly memory. */
980 default_reloc_rw_mask (void)
982 return flag_pic ? 3 : 0;
985 /* By default, do no modification. */
986 tree default_mangle_decl_assembler_name (tree decl ATTRIBUTE_UNUSED,
992 /* Default to natural alignment for vector types. */
994 default_vector_alignment (const_tree type)
996 return tree_low_cst (TYPE_SIZE (type), 0);
1000 default_builtin_vector_alignment_reachable (const_tree type, bool is_packed)
1005 /* Assuming that types whose size is > pointer-size are not guaranteed to be
1006 naturally aligned. */
1007 if (tree_int_cst_compare (TYPE_SIZE (type), bitsize_int (POINTER_SIZE)) > 0)
1010 /* Assuming that types whose size is <= pointer-size
1011 are naturally aligned. */
1015 /* By default, assume that a target supports any factor of misalignment
1016 memory access if it supports movmisalign patten.
1017 is_packed is true if the memory access is defined in a packed struct. */
1019 default_builtin_support_vector_misalignment (enum machine_mode mode,
1027 if (optab_handler (movmisalign_optab, mode) != CODE_FOR_nothing)
1032 /* By default, only attempt to parallelize bitwise operations, and
1033 possibly adds/subtracts using bit-twiddling. */
1036 default_preferred_simd_mode (enum machine_mode mode ATTRIBUTE_UNUSED)
1041 /* By default only the size derived from the preferred vector mode
1045 default_autovectorize_vector_sizes (void)
1050 /* By default, the cost model accumulates three separate costs (prologue,
1051 loop body, and epilogue) for a vectorized loop or block. So allocate an
1052 array of three unsigned ints, set it to zero, and return its address. */
1055 default_init_cost (struct loop *loop_info ATTRIBUTE_UNUSED)
1057 unsigned *cost = XNEWVEC (unsigned, 3);
1058 cost[vect_prologue] = cost[vect_body] = cost[vect_epilogue] = 0;
1062 /* By default, the cost model looks up the cost of the given statement
1063 kind and mode, multiplies it by the occurrence count, accumulates
1064 it into the cost specified by WHERE, and returns the cost added. */
1067 default_add_stmt_cost (void *data, int count, enum vect_cost_for_stmt kind,
1068 struct _stmt_vec_info *stmt_info, int misalign,
1069 enum vect_cost_model_location where)
1071 unsigned *cost = (unsigned *) data;
1072 unsigned retval = 0;
1074 tree vectype = stmt_info ? stmt_vectype (stmt_info) : NULL_TREE;
1075 int stmt_cost = default_builtin_vectorization_cost (kind, vectype,
1077 /* Statements in an inner loop relative to the loop being
1078 vectorized are weighted more heavily. The value here is
1079 arbitrary and could potentially be improved with analysis. */
1080 if (where == vect_body && stmt_info && stmt_in_inner_loop_p (stmt_info))
1081 count *= 50; /* FIXME. */
1083 retval = (unsigned) (count * stmt_cost);
1084 cost[where] += retval;
1089 /* By default, the cost model just returns the accumulated costs. */
1092 default_finish_cost (void *data, unsigned *prologue_cost,
1093 unsigned *body_cost, unsigned *epilogue_cost)
1095 unsigned *cost = (unsigned *) data;
1096 *prologue_cost = cost[vect_prologue];
1097 *body_cost = cost[vect_body];
1098 *epilogue_cost = cost[vect_epilogue];
1101 /* Free the cost data. */
1104 default_destroy_cost_data (void *data)
1109 /* Determine whether or not a pointer mode is valid. Assume defaults
1110 of ptr_mode or Pmode - can be overridden. */
1112 default_valid_pointer_mode (enum machine_mode mode)
1114 return (mode == ptr_mode || mode == Pmode);
1117 /* Determine whether the memory reference specified by REF may alias
1118 the C libraries errno location. */
1120 default_ref_may_alias_errno (ao_ref *ref)
1122 tree base = ao_ref_base (ref);
1123 /* The default implementation assumes the errno location is
1124 a declaration of type int or is always accessed via a
1125 pointer to int. We assume that accesses to errno are
1126 not deliberately obfuscated (even in conforming ways). */
1127 if (TYPE_UNSIGNED (TREE_TYPE (base))
1128 || TYPE_MODE (TREE_TYPE (base)) != TYPE_MODE (integer_type_node))
1130 /* The default implementation assumes an errno location
1131 declaration is never defined in the current compilation unit. */
1133 && !TREE_STATIC (base))
1135 else if (TREE_CODE (base) == MEM_REF
1136 && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME)
1138 struct ptr_info_def *pi = SSA_NAME_PTR_INFO (TREE_OPERAND (base, 0));
1139 return !pi || pi->pt.anything || pi->pt.nonlocal;
1144 /* Return the mode for a pointer to a given ADDRSPACE, defaulting to ptr_mode
1145 for the generic address space only. */
1148 default_addr_space_pointer_mode (addr_space_t addrspace ATTRIBUTE_UNUSED)
1150 gcc_assert (ADDR_SPACE_GENERIC_P (addrspace));
1154 /* Return the mode for an address in a given ADDRSPACE, defaulting to Pmode
1155 for the generic address space only. */
1158 default_addr_space_address_mode (addr_space_t addrspace ATTRIBUTE_UNUSED)
1160 gcc_assert (ADDR_SPACE_GENERIC_P (addrspace));
1164 /* Named address space version of valid_pointer_mode. */
1167 default_addr_space_valid_pointer_mode (enum machine_mode mode, addr_space_t as)
1169 if (!ADDR_SPACE_GENERIC_P (as))
1170 return (mode == targetm.addr_space.pointer_mode (as)
1171 || mode == targetm.addr_space.address_mode (as));
1173 return targetm.valid_pointer_mode (mode);
1176 /* Some places still assume that all pointer or address modes are the
1177 standard Pmode and ptr_mode. These optimizations become invalid if
1178 the target actually supports multiple different modes. For now,
1179 we disable such optimizations on such targets, using this function. */
1182 target_default_pointer_address_modes_p (void)
1184 if (targetm.addr_space.address_mode != default_addr_space_address_mode)
1186 if (targetm.addr_space.pointer_mode != default_addr_space_pointer_mode)
1192 /* Named address space version of legitimate_address_p. */
1195 default_addr_space_legitimate_address_p (enum machine_mode mode, rtx mem,
1196 bool strict, addr_space_t as)
1198 if (!ADDR_SPACE_GENERIC_P (as))
1201 return targetm.legitimate_address_p (mode, mem, strict);
1204 /* Named address space version of LEGITIMIZE_ADDRESS. */
1207 default_addr_space_legitimize_address (rtx x, rtx oldx,
1208 enum machine_mode mode, addr_space_t as)
1210 if (!ADDR_SPACE_GENERIC_P (as))
1213 return targetm.legitimize_address (x, oldx, mode);
1216 /* The default hook for determining if one named address space is a subset of
1217 another and to return which address space to use as the common address
1221 default_addr_space_subset_p (addr_space_t subset, addr_space_t superset)
1223 return (subset == superset);
1226 /* The default hook for TARGET_ADDR_SPACE_CONVERT. This hook should never be
1227 called for targets with only a generic address space. */
1230 default_addr_space_convert (rtx op ATTRIBUTE_UNUSED,
1231 tree from_type ATTRIBUTE_UNUSED,
1232 tree to_type ATTRIBUTE_UNUSED)
1238 default_hard_regno_scratch_ok (unsigned int regno ATTRIBUTE_UNUSED)
1243 /* The default implementation of TARGET_MODE_DEPENDENT_ADDRESS_P. */
1246 default_mode_dependent_address_p (const_rtx addr ATTRIBUTE_UNUSED,
1247 addr_space_t addrspace ATTRIBUTE_UNUSED)
1253 default_target_option_valid_attribute_p (tree ARG_UNUSED (fndecl),
1254 tree ARG_UNUSED (name),
1255 tree ARG_UNUSED (args),
1256 int ARG_UNUSED (flags))
1258 warning (OPT_Wattributes,
1259 "target attribute is not supported on this machine");
1265 default_target_option_pragma_parse (tree ARG_UNUSED (args),
1266 tree ARG_UNUSED (pop_target))
1268 warning (OPT_Wpragmas,
1269 "#pragma GCC target is not supported for this machine");
1275 default_target_can_inline_p (tree caller, tree callee)
1278 tree callee_opts = DECL_FUNCTION_SPECIFIC_TARGET (callee);
1279 tree caller_opts = DECL_FUNCTION_SPECIFIC_TARGET (caller);
1281 /* If callee has no option attributes, then it is ok to inline */
1285 /* If caller has no option attributes, but callee does then it is not ok to
1287 else if (!caller_opts)
1290 /* If both caller and callee have attributes, assume that if the
1291 pointer is different, the two functions have different target
1292 options since build_target_option_node uses a hash table for the
1295 ret = (callee_opts == caller_opts);
1301 # define HAVE_casesi 0
1304 /* If the machine does not have a case insn that compares the bounds,
1305 this means extra overhead for dispatch tables, which raises the
1306 threshold for using them. */
1309 default_case_values_threshold (void)
1311 return (HAVE_casesi ? 4 : 5);
1315 default_have_conditional_execution (void)
1317 #ifdef HAVE_conditional_execution
1318 return HAVE_conditional_execution;
1325 default_builtin_tm_load_store (tree ARG_UNUSED (type))
1330 /* Compute cost of moving registers to/from memory. */
1333 default_memory_move_cost (enum machine_mode mode ATTRIBUTE_UNUSED,
1334 reg_class_t rclass ATTRIBUTE_UNUSED,
1335 bool in ATTRIBUTE_UNUSED)
1337 #ifndef MEMORY_MOVE_COST
1338 return (4 + memory_move_secondary_cost (mode, (enum reg_class) rclass, in));
1340 return MEMORY_MOVE_COST (mode, (enum reg_class) rclass, in);
1344 /* Compute cost of moving data from a register of class FROM to one of
1348 default_register_move_cost (enum machine_mode mode ATTRIBUTE_UNUSED,
1349 reg_class_t from ATTRIBUTE_UNUSED,
1350 reg_class_t to ATTRIBUTE_UNUSED)
1352 #ifndef REGISTER_MOVE_COST
1355 return REGISTER_MOVE_COST (mode, (enum reg_class) from, (enum reg_class) to);
1360 default_profile_before_prologue (void)
1362 #ifdef PROFILE_BEFORE_PROLOGUE
1369 /* The default implementation of TARGET_PREFERRED_RELOAD_CLASS. */
1372 default_preferred_reload_class (rtx x ATTRIBUTE_UNUSED,
1375 #ifdef PREFERRED_RELOAD_CLASS
1376 return (reg_class_t) PREFERRED_RELOAD_CLASS (x, (enum reg_class) rclass);
1382 /* The default implementation of TARGET_OUTPUT_PREFERRED_RELOAD_CLASS. */
1385 default_preferred_output_reload_class (rtx x ATTRIBUTE_UNUSED,
1391 /* The default implementation of TARGET_PREFERRED_RENAME_CLASS. */
1393 default_preferred_rename_class (reg_class_t rclass ATTRIBUTE_UNUSED)
1398 /* The default implementation of TARGET_CLASS_LIKELY_SPILLED_P. */
1401 default_class_likely_spilled_p (reg_class_t rclass)
1403 return (reg_class_size[(int) rclass] == 1);
1406 /* The default implementation of TARGET_CLASS_MAX_NREGS. */
1409 default_class_max_nregs (reg_class_t rclass ATTRIBUTE_UNUSED,
1410 enum machine_mode mode ATTRIBUTE_UNUSED)
1412 #ifdef CLASS_MAX_NREGS
1413 return (unsigned char) CLASS_MAX_NREGS ((enum reg_class) rclass, mode);
1415 return ((GET_MODE_SIZE (mode) + UNITS_PER_WORD - 1) / UNITS_PER_WORD);
1419 /* Determine the debugging unwind mechanism for the target. */
1421 enum unwind_info_type
1422 default_debug_unwind_info (void)
1424 /* If the target wants to force the use of dwarf2 unwind info, let it. */
1425 /* ??? Change all users to the hook, then poison this. */
1426 #ifdef DWARF2_FRAME_INFO
1427 if (DWARF2_FRAME_INFO)
1431 /* Otherwise, only turn it on if dwarf2 debugging is enabled. */
1432 #ifdef DWARF2_DEBUGGING_INFO
1433 if (write_symbols == DWARF2_DEBUG || write_symbols == VMS_AND_DWARF2_DEBUG)
1440 /* To be used by targets where reg_raw_mode doesn't return the right
1441 mode for registers used in apply_builtin_return and apply_builtin_arg. */
1444 default_get_reg_raw_mode (int regno)
1446 return reg_raw_mode[regno];
1449 /* Return true if the state of option OPTION should be stored in PCH files
1450 and checked by default_pch_valid_p. Store the option's current state
1454 option_affects_pch_p (int option, struct cl_option_state *state)
1456 if ((cl_options[option].flags & CL_TARGET) == 0)
1458 if (option_flag_var (option, &global_options) == &target_flags)
1459 if (targetm.check_pch_target_flags)
1461 return get_option_state (&global_options, option, state);
1464 /* Default version of get_pch_validity.
1465 By default, every flag difference is fatal; that will be mostly right for
1466 most targets, but completely right for very few. */
1469 default_get_pch_validity (size_t *sz)
1471 struct cl_option_state state;
1476 if (targetm.check_pch_target_flags)
1477 *sz += sizeof (target_flags);
1478 for (i = 0; i < cl_options_count; i++)
1479 if (option_affects_pch_p (i, &state))
1482 result = r = XNEWVEC (char, *sz);
1486 if (targetm.check_pch_target_flags)
1488 memcpy (r, &target_flags, sizeof (target_flags));
1489 r += sizeof (target_flags);
1492 for (i = 0; i < cl_options_count; i++)
1493 if (option_affects_pch_p (i, &state))
1495 memcpy (r, state.data, state.size);
1502 /* Return a message which says that a PCH file was created with a different
1503 setting of OPTION. */
1506 pch_option_mismatch (const char *option)
1510 asprintf (&r, _("created and used with differing settings of '%s'"), option);
1512 return _("out of memory");
1516 /* Default version of pch_valid_p. */
1519 default_pch_valid_p (const void *data_p, size_t len)
1521 struct cl_option_state state;
1522 const char *data = (const char *)data_p;
1525 /* -fpic and -fpie also usually make a PCH invalid. */
1526 if (data[0] != flag_pic)
1527 return _("created and used with different settings of -fpic");
1528 if (data[1] != flag_pie)
1529 return _("created and used with different settings of -fpie");
1532 /* Check target_flags. */
1533 if (targetm.check_pch_target_flags)
1538 memcpy (&tf, data, sizeof (target_flags));
1539 data += sizeof (target_flags);
1540 len -= sizeof (target_flags);
1541 r = targetm.check_pch_target_flags (tf);
1546 for (i = 0; i < cl_options_count; i++)
1547 if (option_affects_pch_p (i, &state))
1549 if (memcmp (data, state.data, state.size) != 0)
1550 return pch_option_mismatch (cl_options[i].opt_text);
1558 /* Default version of cstore_mode. */
1561 default_cstore_mode (enum insn_code icode)
1563 return insn_data[(int) icode].operand[0].mode;
1566 /* Default version of member_type_forces_blk. */
1569 default_member_type_forces_blk (const_tree, enum machine_mode)
1574 default_load_bounds_for_arg (rtx addr ATTRIBUTE_UNUSED,
1575 rtx ptr ATTRIBUTE_UNUSED,
1576 rtx bnd ATTRIBUTE_UNUSED)
1582 default_store_bounds_for_arg (rtx val ATTRIBUTE_UNUSED,
1583 rtx addr ATTRIBUTE_UNUSED,
1584 rtx bounds ATTRIBUTE_UNUSED,
1585 rtx to ATTRIBUTE_UNUSED)
1591 default_fn_abi_va_list_bounds_size (tree fndecl ATTRIBUTE_UNUSED)
1593 return integer_zero_node;
1596 /* Default version of canonicalize_comparison. */
1599 default_canonicalize_comparison (int *, rtx *, rtx *, bool)
1603 #ifndef PAD_VARARGS_DOWN
1604 #define PAD_VARARGS_DOWN BYTES_BIG_ENDIAN
1607 /* Build an indirect-ref expression over the given TREE, which represents a
1608 piece of a va_arg() expansion. */
1610 build_va_arg_indirect_ref (tree addr)
1612 addr = build_simple_mem_ref_loc (EXPR_LOCATION (addr), addr);
1616 /* The "standard" implementation of va_arg: read the value from the
1617 current (padded) address and increment by the (padded) size. */
1620 std_gimplify_va_arg_expr (tree valist, tree type, gimple_seq *pre_p,
1623 tree addr, t, type_size, rounded_size, valist_tmp;
1624 unsigned HOST_WIDE_INT align, boundary;
1627 #ifdef ARGS_GROW_DOWNWARD
1628 /* All of the alignment and movement below is for args-grow-up machines.
1629 As of 2004, there are only 3 ARGS_GROW_DOWNWARD targets, and they all
1630 implement their own specialized gimplify_va_arg_expr routines. */
1634 indirect = pass_by_reference (NULL, TYPE_MODE (type), type, false);
1636 type = build_pointer_type (type);
1638 align = PARM_BOUNDARY / BITS_PER_UNIT;
1639 boundary = targetm.calls.function_arg_boundary (TYPE_MODE (type), type);
1641 /* When we align parameter on stack for caller, if the parameter
1642 alignment is beyond MAX_SUPPORTED_STACK_ALIGNMENT, it will be
1643 aligned at MAX_SUPPORTED_STACK_ALIGNMENT. We will match callee
1644 here with caller. */
1645 if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
1646 boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
1648 boundary /= BITS_PER_UNIT;
1650 /* Hoist the valist value into a temporary for the moment. */
1651 valist_tmp = get_initialized_tmp_var (valist, pre_p, NULL);
1653 /* va_list pointer is aligned to PARM_BOUNDARY. If argument actually
1654 requires greater alignment, we must perform dynamic alignment. */
1655 if (boundary > align
1656 && !integer_zerop (TYPE_SIZE (type)))
1658 t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist_tmp,
1659 fold_build_pointer_plus_hwi (valist_tmp, boundary - 1));
1660 gimplify_and_add (t, pre_p);
1662 t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist_tmp,
1663 fold_build2 (BIT_AND_EXPR, TREE_TYPE (valist),
1665 build_int_cst (TREE_TYPE (valist), -boundary)));
1666 gimplify_and_add (t, pre_p);
1671 /* If the actual alignment is less than the alignment of the type,
1672 adjust the type accordingly so that we don't assume strict alignment
1673 when dereferencing the pointer. */
1674 boundary *= BITS_PER_UNIT;
1675 if (boundary < TYPE_ALIGN (type))
1677 type = build_variant_type_copy (type);
1678 TYPE_ALIGN (type) = boundary;
1681 /* Compute the rounded size of the type. */
1682 type_size = size_in_bytes (type);
1683 rounded_size = round_up (type_size, align);
1685 /* Reduce rounded_size so it's sharable with the postqueue. */
1686 gimplify_expr (&rounded_size, pre_p, post_p, is_gimple_val, fb_rvalue);
1690 if (PAD_VARARGS_DOWN && !integer_zerop (rounded_size))
1692 /* Small args are padded downward. */
1693 t = fold_build2_loc (input_location, GT_EXPR, sizetype,
1694 rounded_size, size_int (align));
1695 t = fold_build3 (COND_EXPR, sizetype, t, size_zero_node,
1696 size_binop (MINUS_EXPR, rounded_size, type_size));
1697 addr = fold_build_pointer_plus (addr, t);
1700 /* Compute new value for AP. */
1701 t = fold_build_pointer_plus (valist_tmp, rounded_size);
1702 t = build2 (MODIFY_EXPR, TREE_TYPE (valist), valist, t);
1703 gimplify_and_add (t, pre_p);
1705 addr = fold_convert (build_pointer_type (type), addr);
1708 addr = build_va_arg_indirect_ref (addr);
1710 return build_va_arg_indirect_ref (addr);
1714 default_chkp_bound_type (void)
1716 tree res = make_node (POINTER_BOUNDS_TYPE);
1717 TYPE_PRECISION (res) = TYPE_PRECISION (size_type_node) * 2;
1723 default_chkp_bound_mode (void)
1729 default_builtin_chkp_function (unsigned int fcode ATTRIBUTE_UNUSED)
1735 #include "gt-targhooks.h"