1 /* Default target hook functions.
2 Copyright (C) 2003-2022 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"
56 #include "tree-ssa-alias.h"
57 #include "gimple-expr.h"
63 #include "stringpool.h"
65 #include "tree-ssanames.h"
66 #include "profile-count.h"
70 #include "diagnostic-core.h"
71 #include "fold-const.h"
72 #include "stor-layout.h"
80 #include "common/common-target.h"
87 #include "langhooks.h"
89 #include "function-abi.h"
95 #include "tree-vectorizer.h"
98 default_legitimate_address_p (machine_mode mode ATTRIBUTE_UNUSED
,
99 rtx addr ATTRIBUTE_UNUSED
,
100 bool strict ATTRIBUTE_UNUSED
)
102 #ifdef GO_IF_LEGITIMATE_ADDRESS
103 /* Defer to the old implementation using a goto. */
105 return strict_memory_address_p (mode
, addr
);
107 return memory_address_p (mode
, addr
);
114 default_external_libcall (rtx fun ATTRIBUTE_UNUSED
)
116 #ifdef ASM_OUTPUT_EXTERNAL_LIBCALL
117 ASM_OUTPUT_EXTERNAL_LIBCALL (asm_out_file
, fun
);
122 default_unspec_may_trap_p (const_rtx x
, unsigned flags
)
126 /* Any floating arithmetic may trap. */
127 if ((SCALAR_FLOAT_MODE_P (GET_MODE (x
)) && flag_trapping_math
))
130 for (i
= 0; i
< XVECLEN (x
, 0); ++i
)
132 if (may_trap_p_1 (XVECEXP (x
, 0, i
), flags
))
140 default_promote_function_mode (const_tree type ATTRIBUTE_UNUSED
,
142 int *punsignedp ATTRIBUTE_UNUSED
,
143 const_tree funtype ATTRIBUTE_UNUSED
,
144 int for_return ATTRIBUTE_UNUSED
)
146 if (type
!= NULL_TREE
&& for_return
== 2)
147 return promote_mode (type
, mode
, punsignedp
);
152 default_promote_function_mode_always_promote (const_tree type
,
155 const_tree funtype ATTRIBUTE_UNUSED
,
156 int for_return ATTRIBUTE_UNUSED
)
158 return promote_mode (type
, mode
, punsignedp
);
162 default_cc_modes_compatible (machine_mode m1
, machine_mode m2
)
170 default_return_in_memory (const_tree type
,
171 const_tree fntype ATTRIBUTE_UNUSED
)
173 return (TYPE_MODE (type
) == BLKmode
);
177 default_legitimize_address (rtx x
, rtx orig_x ATTRIBUTE_UNUSED
,
178 machine_mode mode ATTRIBUTE_UNUSED
)
184 default_legitimize_address_displacement (rtx
*, rtx
*, poly_int64
,
191 default_const_not_ok_for_debug_p (rtx x
)
193 if (GET_CODE (x
) == UNSPEC
)
199 default_expand_builtin_saveregs (void)
201 error ("%<__builtin_saveregs%> not supported by this target");
206 default_setup_incoming_varargs (cumulative_args_t
,
207 const function_arg_info
&, int *, int)
211 /* The default implementation of TARGET_BUILTIN_SETJMP_FRAME_VALUE. */
214 default_builtin_setjmp_frame_value (void)
216 return virtual_stack_vars_rtx
;
219 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns false. */
222 hook_bool_CUMULATIVE_ARGS_false (cumulative_args_t ca ATTRIBUTE_UNUSED
)
228 default_pretend_outgoing_varargs_named (cumulative_args_t ca ATTRIBUTE_UNUSED
)
230 return (targetm
.calls
.setup_incoming_varargs
231 != default_setup_incoming_varargs
);
235 default_eh_return_filter_mode (void)
237 return targetm
.unwind_word_mode ();
241 default_libgcc_cmp_return_mode (void)
247 default_libgcc_shift_count_mode (void)
253 default_unwind_word_mode (void)
258 /* The default implementation of TARGET_SHIFT_TRUNCATION_MASK. */
260 unsigned HOST_WIDE_INT
261 default_shift_truncation_mask (machine_mode mode
)
263 return SHIFT_COUNT_TRUNCATED
? GET_MODE_UNIT_BITSIZE (mode
) - 1 : 0;
266 /* The default implementation of TARGET_MIN_DIVISIONS_FOR_RECIP_MUL. */
269 default_min_divisions_for_recip_mul (machine_mode mode ATTRIBUTE_UNUSED
)
271 return have_insn_for (DIV
, mode
) ? 3 : 2;
274 /* The default implementation of TARGET_MODE_REP_EXTENDED. */
277 default_mode_rep_extended (scalar_int_mode
, scalar_int_mode
)
282 /* Generic hook that takes a CUMULATIVE_ARGS pointer and returns true. */
285 hook_bool_CUMULATIVE_ARGS_true (cumulative_args_t a ATTRIBUTE_UNUSED
)
290 /* Return machine mode for non-standard suffix
291 or VOIDmode if non-standard suffixes are unsupported. */
293 default_mode_for_suffix (char suffix ATTRIBUTE_UNUSED
)
298 /* The generic C++ ABI specifies this is a 64-bit value. */
300 default_cxx_guard_type (void)
302 return long_long_integer_type_node
;
305 /* Returns the size of the cookie to use when allocating an array
306 whose elements have the indicated TYPE. Assumes that it is already
307 known that a cookie is needed. */
310 default_cxx_get_cookie_size (tree type
)
314 /* We need to allocate an additional max (sizeof (size_t), alignof
315 (true_type)) bytes. */
319 sizetype_size
= size_in_bytes (sizetype
);
320 type_align
= size_int (TYPE_ALIGN_UNIT (type
));
321 if (tree_int_cst_lt (type_align
, sizetype_size
))
322 cookie_size
= sizetype_size
;
324 cookie_size
= type_align
;
329 /* Return true if a parameter must be passed by reference. This version
330 of the TARGET_PASS_BY_REFERENCE hook uses just MUST_PASS_IN_STACK. */
333 hook_pass_by_reference_must_pass_in_stack (cumulative_args_t
,
334 const function_arg_info
&arg
)
336 return targetm
.calls
.must_pass_in_stack (arg
);
339 /* Return true if a parameter follows callee copies conventions. This
340 version of the hook is true for all named arguments. */
343 hook_callee_copies_named (cumulative_args_t
, const function_arg_info
&arg
)
348 /* Emit to STREAM the assembler syntax for insn operand X. */
351 default_print_operand (FILE *stream ATTRIBUTE_UNUSED
, rtx x ATTRIBUTE_UNUSED
,
352 int code ATTRIBUTE_UNUSED
)
355 PRINT_OPERAND (stream
, x
, code
);
361 /* Emit to STREAM the assembler syntax for an insn operand whose memory
365 default_print_operand_address (FILE *stream ATTRIBUTE_UNUSED
,
366 machine_mode
/*mode*/,
367 rtx x ATTRIBUTE_UNUSED
)
369 #ifdef PRINT_OPERAND_ADDRESS
370 PRINT_OPERAND_ADDRESS (stream
, x
);
376 /* Return true if CODE is a valid punctuation character for the
377 `print_operand' hook. */
380 default_print_operand_punct_valid_p (unsigned char code ATTRIBUTE_UNUSED
)
382 #ifdef PRINT_OPERAND_PUNCT_VALID_P
383 return PRINT_OPERAND_PUNCT_VALID_P (code
);
389 /* The default implementation of TARGET_MANGLE_ASSEMBLER_NAME. */
391 default_mangle_assembler_name (const char *name ATTRIBUTE_UNUSED
)
393 const char *skipped
= name
+ (*name
== '*' ? 1 : 0);
394 const char *stripped
= targetm
.strip_name_encoding (skipped
);
395 if (*name
!= '*' && user_label_prefix
[0])
396 stripped
= ACONCAT ((user_label_prefix
, stripped
, NULL
));
397 return get_identifier (stripped
);
400 /* The default implementation of TARGET_TRANSLATE_MODE_ATTRIBUTE. */
403 default_translate_mode_attribute (machine_mode mode
)
408 /* True if MODE is valid for the target. By "valid", we mean able to
409 be manipulated in non-trivial ways. In particular, this means all
410 the arithmetic is supported.
412 By default we guess this means that any C type is supported. If
413 we can't map the mode back to a type that would be available in C,
414 then reject it. Special case, here, is the double-word arithmetic
415 supported by optabs.c. */
418 default_scalar_mode_supported_p (scalar_mode mode
)
420 int precision
= GET_MODE_PRECISION (mode
);
422 switch (GET_MODE_CLASS (mode
))
424 case MODE_PARTIAL_INT
:
426 if (precision
== CHAR_TYPE_SIZE
)
428 if (precision
== SHORT_TYPE_SIZE
)
430 if (precision
== INT_TYPE_SIZE
)
432 if (precision
== LONG_TYPE_SIZE
)
434 if (precision
== LONG_LONG_TYPE_SIZE
)
436 if (precision
== 2 * BITS_PER_WORD
)
441 if (precision
== FLOAT_TYPE_SIZE
)
443 if (precision
== DOUBLE_TYPE_SIZE
)
445 if (precision
== LONG_DOUBLE_TYPE_SIZE
)
449 case MODE_DECIMAL_FLOAT
:
461 /* Return true if libgcc supports floating-point mode MODE (known to
462 be supported as a scalar mode). */
465 default_libgcc_floating_mode_supported_p (scalar_float_mode mode
)
488 /* Return the machine mode to use for the type _FloatN, if EXTENDED is
489 false, or _FloatNx, if EXTENDED is true, or VOIDmode if not
491 opt_scalar_float_mode
492 default_floatn_mode (int n
, bool extended
)
496 opt_scalar_float_mode cand1
, cand2
;
497 scalar_float_mode mode
;
519 /* Those are the only valid _FloatNx types. */
522 if (cand1
.exists (&mode
)
523 && REAL_MODE_FORMAT (mode
)->ieee_bits
> n
524 && targetm
.scalar_mode_supported_p (mode
)
525 && targetm
.libgcc_floating_mode_supported_p (mode
))
527 if (cand2
.exists (&mode
)
528 && REAL_MODE_FORMAT (mode
)->ieee_bits
> n
529 && targetm
.scalar_mode_supported_p (mode
)
530 && targetm
.libgcc_floating_mode_supported_p (mode
))
535 opt_scalar_float_mode cand
;
536 scalar_float_mode mode
;
540 /* Always enable _Float16 if we have basic support for the mode.
541 Targets can control the range and precision of operations on
542 the _Float16 type using TARGET_C_EXCESS_PRECISION. */
569 if (cand
.exists (&mode
)
570 && REAL_MODE_FORMAT (mode
)->ieee_bits
== n
571 && targetm
.scalar_mode_supported_p (mode
)
572 && targetm
.libgcc_floating_mode_supported_p (mode
))
575 return opt_scalar_float_mode ();
578 /* Define this to return true if the _Floatn and _Floatnx built-in functions
579 should implicitly enable the built-in function without the __builtin_ prefix
580 in addition to the normal built-in function with the __builtin_ prefix. The
581 default is to only enable built-in functions without the __builtin_ prefix
582 for the GNU C langauge. The argument FUNC is the enum builtin_in_function
583 id of the function to be enabled. */
586 default_floatn_builtin_p (int func ATTRIBUTE_UNUSED
)
588 static bool first_time_p
= true;
589 static bool c_or_objective_c
;
593 first_time_p
= false;
594 c_or_objective_c
= lang_GNU_C () || lang_GNU_OBJC ();
597 return c_or_objective_c
;
600 /* Make some target macros useable by target-independent code. */
602 targhook_words_big_endian (void)
604 return !!WORDS_BIG_ENDIAN
;
608 targhook_float_words_big_endian (void)
610 return !!FLOAT_WORDS_BIG_ENDIAN
;
613 /* True if the target supports floating-point exceptions and rounding
617 default_float_exceptions_rounding_supported_p (void)
626 /* True if the target supports decimal floating point. */
629 default_decimal_float_supported_p (void)
631 return ENABLE_DECIMAL_FLOAT
;
634 /* True if the target supports fixed-point arithmetic. */
637 default_fixed_point_supported_p (void)
639 return ENABLE_FIXED_POINT
;
642 /* True if the target supports GNU indirect functions. */
645 default_has_ifunc_p (void)
647 return HAVE_GNU_INDIRECT_FUNCTION
;
650 /* Return true if we predict the loop LOOP will be transformed to a
651 low-overhead loop, otherwise return false.
653 By default, false is returned, as this hook's applicability should be
654 verified for each target. Target maintainers should re-define the hook
655 if the target can take advantage of it. */
658 default_predict_doloop_p (class loop
*loop ATTRIBUTE_UNUSED
)
663 /* By default, just use the input MODE itself. */
666 default_preferred_doloop_mode (machine_mode mode
)
671 /* NULL if INSN insn is valid within a low-overhead loop, otherwise returns
674 This function checks whether a given INSN is valid within a low-overhead
675 loop. If INSN is invalid it returns the reason for that, otherwise it
676 returns NULL. A called function may clobber any special registers required
677 for low-overhead looping. Additionally, some targets (eg, PPC) use the count
678 register for branch on table instructions. We reject the doloop pattern in
682 default_invalid_within_doloop (const rtx_insn
*insn
)
685 return "Function call in loop.";
687 if (tablejump_p (insn
, NULL
, NULL
) || computed_jump_p (insn
))
688 return "Computed branch in the loop.";
693 /* Mapping of builtin functions to vectorized variants. */
696 default_builtin_vectorized_function (unsigned int, tree
, tree
)
701 /* Mapping of target builtin functions to vectorized variants. */
704 default_builtin_md_vectorized_function (tree
, tree
, tree
)
709 /* Default vectorizer cost model values. */
712 default_builtin_vectorization_cost (enum vect_cost_for_stmt type_of_cost
,
714 int misalign ATTRIBUTE_UNUSED
)
716 switch (type_of_cost
)
726 case cond_branch_not_taken
:
728 case vec_promote_demote
:
732 case unaligned_store
:
735 case cond_branch_taken
:
739 return estimated_poly_value (TYPE_VECTOR_SUBPARTS (vectype
)) - 1;
749 default_builtin_reciprocal (tree
)
755 hook_bool_CUMULATIVE_ARGS_arg_info_false (cumulative_args_t
,
756 const function_arg_info
&)
762 hook_bool_CUMULATIVE_ARGS_arg_info_true (cumulative_args_t
,
763 const function_arg_info
&)
769 hook_int_CUMULATIVE_ARGS_arg_info_0 (cumulative_args_t
,
770 const function_arg_info
&)
776 hook_void_CUMULATIVE_ARGS_tree (cumulative_args_t ca ATTRIBUTE_UNUSED
,
777 tree ATTRIBUTE_UNUSED
)
781 /* Default implementation of TARGET_PUSH_ARGUMENT. */
784 default_push_argument (unsigned int)
787 return !ACCUMULATE_OUTGOING_ARGS
;
794 default_function_arg_advance (cumulative_args_t
, const function_arg_info
&)
799 /* Default implementation of TARGET_FUNCTION_ARG_OFFSET. */
802 default_function_arg_offset (machine_mode
, const_tree
)
807 /* Default implementation of TARGET_FUNCTION_ARG_PADDING: usually pad
808 upward, but pad short args downward on big-endian machines. */
811 default_function_arg_padding (machine_mode mode
, const_tree type
)
813 if (!BYTES_BIG_ENDIAN
)
816 unsigned HOST_WIDE_INT size
;
819 if (!type
|| TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
821 size
= int_size_in_bytes (type
);
824 /* Targets with variable-sized modes must override this hook
825 and handle variable-sized modes explicitly. */
826 size
= GET_MODE_SIZE (mode
).to_constant ();
828 if (size
< (PARM_BOUNDARY
/ BITS_PER_UNIT
))
835 default_function_arg (cumulative_args_t
, const function_arg_info
&)
841 default_function_incoming_arg (cumulative_args_t
, const function_arg_info
&)
847 default_function_arg_boundary (machine_mode mode ATTRIBUTE_UNUSED
,
848 const_tree type ATTRIBUTE_UNUSED
)
850 return PARM_BOUNDARY
;
854 default_function_arg_round_boundary (machine_mode mode ATTRIBUTE_UNUSED
,
855 const_tree type ATTRIBUTE_UNUSED
)
857 return PARM_BOUNDARY
;
861 hook_void_bitmap (bitmap regs ATTRIBUTE_UNUSED
)
866 hook_invalid_arg_for_unprototyped_fn (
867 const_tree typelist ATTRIBUTE_UNUSED
,
868 const_tree funcdecl ATTRIBUTE_UNUSED
,
869 const_tree val ATTRIBUTE_UNUSED
)
874 /* Initialize the stack protection decls. */
876 /* Stack protection related decls living in libgcc. */
877 static GTY(()) tree stack_chk_guard_decl
;
880 default_stack_protect_guard (void)
882 tree t
= stack_chk_guard_decl
;
888 t
= build_decl (UNKNOWN_LOCATION
,
889 VAR_DECL
, get_identifier ("__stack_chk_guard"),
893 DECL_EXTERNAL (t
) = 1;
895 TREE_THIS_VOLATILE (t
) = 1;
896 DECL_ARTIFICIAL (t
) = 1;
897 DECL_IGNORED_P (t
) = 1;
899 /* Do not share RTL as the declaration is visible outside of
902 RTX_FLAG (x
, used
) = 1;
904 stack_chk_guard_decl
= t
;
910 static GTY(()) tree stack_chk_fail_decl
;
913 default_external_stack_protect_fail (void)
915 tree t
= stack_chk_fail_decl
;
919 t
= build_function_type_list (void_type_node
, NULL_TREE
);
920 t
= build_decl (UNKNOWN_LOCATION
,
921 FUNCTION_DECL
, get_identifier ("__stack_chk_fail"), t
);
924 DECL_EXTERNAL (t
) = 1;
926 TREE_THIS_VOLATILE (t
) = 1;
927 TREE_NOTHROW (t
) = 1;
928 DECL_ARTIFICIAL (t
) = 1;
929 DECL_IGNORED_P (t
) = 1;
930 DECL_VISIBILITY (t
) = VISIBILITY_DEFAULT
;
931 DECL_VISIBILITY_SPECIFIED (t
) = 1;
933 stack_chk_fail_decl
= t
;
936 return build_call_expr (t
, 0);
940 default_hidden_stack_protect_fail (void)
942 #ifndef HAVE_GAS_HIDDEN
943 return default_external_stack_protect_fail ();
945 tree t
= stack_chk_fail_decl
;
948 return default_external_stack_protect_fail ();
952 t
= build_function_type_list (void_type_node
, NULL_TREE
);
953 t
= build_decl (UNKNOWN_LOCATION
, FUNCTION_DECL
,
954 get_identifier ("__stack_chk_fail_local"), t
);
957 DECL_EXTERNAL (t
) = 1;
959 TREE_THIS_VOLATILE (t
) = 1;
960 TREE_NOTHROW (t
) = 1;
961 DECL_ARTIFICIAL (t
) = 1;
962 DECL_IGNORED_P (t
) = 1;
963 DECL_VISIBILITY_SPECIFIED (t
) = 1;
964 DECL_VISIBILITY (t
) = VISIBILITY_HIDDEN
;
966 stack_chk_fail_decl
= t
;
969 return build_call_expr (t
, 0);
974 hook_bool_const_rtx_commutative_p (const_rtx x
,
975 int outer_code ATTRIBUTE_UNUSED
)
977 return COMMUTATIVE_P (x
);
981 default_function_value (const_tree ret_type ATTRIBUTE_UNUSED
,
982 const_tree fn_decl_or_type
,
983 bool outgoing ATTRIBUTE_UNUSED
)
985 /* The old interface doesn't handle receiving the function type. */
987 && !DECL_P (fn_decl_or_type
))
988 fn_decl_or_type
= NULL
;
990 #ifdef FUNCTION_VALUE
991 return FUNCTION_VALUE (ret_type
, fn_decl_or_type
);
998 default_libcall_value (machine_mode mode ATTRIBUTE_UNUSED
,
999 const_rtx fun ATTRIBUTE_UNUSED
)
1001 #ifdef LIBCALL_VALUE
1002 return LIBCALL_VALUE (MACRO_MODE (mode
));
1008 /* The default hook for TARGET_FUNCTION_VALUE_REGNO_P. */
1011 default_function_value_regno_p (const unsigned int regno ATTRIBUTE_UNUSED
)
1013 #ifdef FUNCTION_VALUE_REGNO_P
1014 return FUNCTION_VALUE_REGNO_P (regno
);
1020 /* The default hook for TARGET_ZERO_CALL_USED_REGS. */
1023 default_zero_call_used_regs (HARD_REG_SET need_zeroed_hardregs
)
1025 gcc_assert (!hard_reg_set_empty_p (need_zeroed_hardregs
));
1027 HARD_REG_SET failed
;
1028 CLEAR_HARD_REG_SET (failed
);
1029 bool progress
= false;
1031 /* First, try to zero each register in need_zeroed_hardregs by
1032 loading a zero into it, taking note of any failures in
1034 for (unsigned int regno
= 0; regno
< FIRST_PSEUDO_REGISTER
; regno
++)
1035 if (TEST_HARD_REG_BIT (need_zeroed_hardregs
, regno
))
1037 rtx_insn
*last_insn
= get_last_insn ();
1038 machine_mode mode
= GET_MODE (regno_reg_rtx
[regno
]);
1039 rtx zero
= CONST0_RTX (mode
);
1040 rtx_insn
*insn
= emit_move_insn (regno_reg_rtx
[regno
], zero
);
1041 if (!valid_insn_p (insn
))
1043 SET_HARD_REG_BIT (failed
, regno
);
1044 delete_insns_since (last_insn
);
1050 /* Now retry with copies from zeroed registers, as long as we've
1051 made some PROGRESS, and registers remain to be zeroed in
1053 while (progress
&& !hard_reg_set_empty_p (failed
))
1055 HARD_REG_SET retrying
= failed
;
1057 CLEAR_HARD_REG_SET (failed
);
1060 for (unsigned int regno
= 0; regno
< FIRST_PSEUDO_REGISTER
; regno
++)
1061 if (TEST_HARD_REG_BIT (retrying
, regno
))
1063 machine_mode mode
= GET_MODE (regno_reg_rtx
[regno
]);
1064 bool success
= false;
1065 /* Look for a source. */
1066 for (unsigned int src
= 0; src
< FIRST_PSEUDO_REGISTER
; src
++)
1068 /* If SRC hasn't been zeroed (yet?), skip it. */
1069 if (! TEST_HARD_REG_BIT (need_zeroed_hardregs
, src
))
1071 if (TEST_HARD_REG_BIT (retrying
, src
))
1074 /* Check that SRC can hold MODE, and that any other
1075 registers needed to hold MODE in SRC have also been
1077 if (!targetm
.hard_regno_mode_ok (src
, mode
))
1079 unsigned n
= targetm
.hard_regno_nregs (src
, mode
);
1081 for (unsigned i
= 1; ok
&& i
< n
; i
++)
1082 ok
= (TEST_HARD_REG_BIT (need_zeroed_hardregs
, src
+ i
)
1083 && !TEST_HARD_REG_BIT (retrying
, src
+ i
));
1087 /* SRC is usable, try to copy from it. */
1088 rtx_insn
*last_insn
= get_last_insn ();
1089 rtx zsrc
= gen_rtx_REG (mode
, src
);
1090 rtx_insn
*insn
= emit_move_insn (regno_reg_rtx
[regno
], zsrc
);
1091 if (!valid_insn_p (insn
))
1092 /* It didn't work, remove any inserts. We'll look
1094 delete_insns_since (last_insn
);
1097 /* We're done for REGNO. */
1103 /* If nothing worked for REGNO this round, marked it to be
1104 retried if we get another round. */
1106 SET_HARD_REG_BIT (failed
, regno
);
1108 /* Take note so as to enable another round if needed. */
1113 /* If any register remained, report it. */
1116 static bool issued_error
;
1119 issued_error
= true;
1120 sorry ("%qs not supported on this target",
1121 "-fzero-call-used-regs");
1125 return need_zeroed_hardregs
;
1129 default_internal_arg_pointer (void)
1131 /* If the reg that the virtual arg pointer will be translated into is
1132 not a fixed reg or is the stack pointer, make a copy of the virtual
1133 arg pointer, and address parms via the copy. The frame pointer is
1134 considered fixed even though it is not marked as such. */
1135 if ((ARG_POINTER_REGNUM
== STACK_POINTER_REGNUM
1136 || ! (fixed_regs
[ARG_POINTER_REGNUM
]
1137 || ARG_POINTER_REGNUM
== FRAME_POINTER_REGNUM
)))
1138 return copy_to_reg (virtual_incoming_args_rtx
);
1140 return virtual_incoming_args_rtx
;
1144 default_static_chain (const_tree
ARG_UNUSED (fndecl_or_type
), bool incoming_p
)
1148 #ifdef STATIC_CHAIN_INCOMING_REGNUM
1149 return gen_rtx_REG (Pmode
, STATIC_CHAIN_INCOMING_REGNUM
);
1153 #ifdef STATIC_CHAIN_REGNUM
1154 return gen_rtx_REG (Pmode
, STATIC_CHAIN_REGNUM
);
1158 static bool issued_error
;
1161 issued_error
= true;
1162 sorry ("nested functions not supported on this target");
1165 /* It really doesn't matter what we return here, so long at it
1166 doesn't cause the rest of the compiler to crash. */
1167 return gen_rtx_MEM (Pmode
, stack_pointer_rtx
);
1172 default_trampoline_init (rtx
ARG_UNUSED (m_tramp
), tree
ARG_UNUSED (t_func
),
1173 rtx
ARG_UNUSED (r_chain
))
1175 sorry ("nested function trampolines not supported on this target");
1179 default_return_pops_args (tree
, tree
, poly_int64
)
1185 default_ira_change_pseudo_allocno_class (int regno ATTRIBUTE_UNUSED
,
1187 reg_class_t best_cl ATTRIBUTE_UNUSED
)
1193 default_lra_p (void)
1199 default_register_priority (int hard_regno ATTRIBUTE_UNUSED
)
1205 default_register_usage_leveling_p (void)
1211 default_different_addr_displacement_p (void)
1217 default_secondary_reload (bool in_p ATTRIBUTE_UNUSED
, rtx x ATTRIBUTE_UNUSED
,
1218 reg_class_t reload_class_i ATTRIBUTE_UNUSED
,
1219 machine_mode reload_mode ATTRIBUTE_UNUSED
,
1220 secondary_reload_info
*sri
)
1222 enum reg_class rclass
= NO_REGS
;
1223 enum reg_class reload_class
= (enum reg_class
) reload_class_i
;
1225 if (sri
->prev_sri
&& sri
->prev_sri
->t_icode
!= CODE_FOR_nothing
)
1227 sri
->icode
= sri
->prev_sri
->t_icode
;
1230 #ifdef SECONDARY_INPUT_RELOAD_CLASS
1232 rclass
= SECONDARY_INPUT_RELOAD_CLASS (reload_class
,
1233 MACRO_MODE (reload_mode
), x
);
1235 #ifdef SECONDARY_OUTPUT_RELOAD_CLASS
1237 rclass
= SECONDARY_OUTPUT_RELOAD_CLASS (reload_class
,
1238 MACRO_MODE (reload_mode
), x
);
1240 if (rclass
!= NO_REGS
)
1242 enum insn_code icode
1243 = direct_optab_handler (in_p
? reload_in_optab
: reload_out_optab
,
1246 if (icode
!= CODE_FOR_nothing
1247 && !insn_operand_matches (icode
, in_p
, x
))
1248 icode
= CODE_FOR_nothing
;
1249 else if (icode
!= CODE_FOR_nothing
)
1251 const char *insn_constraint
, *scratch_constraint
;
1252 enum reg_class insn_class
, scratch_class
;
1254 gcc_assert (insn_data
[(int) icode
].n_operands
== 3);
1255 insn_constraint
= insn_data
[(int) icode
].operand
[!in_p
].constraint
;
1256 if (!*insn_constraint
)
1257 insn_class
= ALL_REGS
;
1262 gcc_assert (*insn_constraint
== '=');
1265 insn_class
= (reg_class_for_constraint
1266 (lookup_constraint (insn_constraint
)));
1267 gcc_assert (insn_class
!= NO_REGS
);
1270 scratch_constraint
= insn_data
[(int) icode
].operand
[2].constraint
;
1271 /* The scratch register's constraint must start with "=&",
1272 except for an input reload, where only "=" is necessary,
1273 and where it might be beneficial to re-use registers from
1275 gcc_assert (scratch_constraint
[0] == '='
1276 && (in_p
|| scratch_constraint
[1] == '&'));
1277 scratch_constraint
++;
1278 if (*scratch_constraint
== '&')
1279 scratch_constraint
++;
1280 scratch_class
= (reg_class_for_constraint
1281 (lookup_constraint (scratch_constraint
)));
1283 if (reg_class_subset_p (reload_class
, insn_class
))
1285 gcc_assert (scratch_class
== rclass
);
1289 rclass
= insn_class
;
1292 if (rclass
== NO_REGS
)
1295 sri
->t_icode
= icode
;
1300 /* The default implementation of TARGET_SECONDARY_MEMORY_NEEDED_MODE. */
1303 default_secondary_memory_needed_mode (machine_mode mode
)
1305 if (!targetm
.lra_p ()
1306 && known_lt (GET_MODE_BITSIZE (mode
), BITS_PER_WORD
)
1307 && INTEGRAL_MODE_P (mode
))
1308 return mode_for_size (BITS_PER_WORD
, GET_MODE_CLASS (mode
), 0).require ();
1312 /* By default, if flag_pic is true, then neither local nor global relocs
1313 should be placed in readonly memory. */
1316 default_reloc_rw_mask (void)
1318 return flag_pic
? 3 : 0;
1321 /* By default, address diff vectors are generated
1322 for jump tables when flag_pic is true. */
1325 default_generate_pic_addr_diff_vec (void)
1330 /* By default, do no modification. */
1331 tree
default_mangle_decl_assembler_name (tree decl ATTRIBUTE_UNUSED
,
1337 /* The default implementation of TARGET_STATIC_RTX_ALIGNMENT. */
1340 default_static_rtx_alignment (machine_mode mode
)
1342 return GET_MODE_ALIGNMENT (mode
);
1345 /* The default implementation of TARGET_CONSTANT_ALIGNMENT. */
1348 default_constant_alignment (const_tree
, HOST_WIDE_INT align
)
1353 /* An implementation of TARGET_CONSTANT_ALIGNMENT that aligns strings
1354 to at least BITS_PER_WORD but otherwise makes no changes. */
1357 constant_alignment_word_strings (const_tree exp
, HOST_WIDE_INT align
)
1359 if (TREE_CODE (exp
) == STRING_CST
)
1360 return MAX (align
, BITS_PER_WORD
);
1364 /* Default to natural alignment for vector types, bounded by
1365 MAX_OFILE_ALIGNMENT. */
1368 default_vector_alignment (const_tree type
)
1370 unsigned HOST_WIDE_INT align
= MAX_OFILE_ALIGNMENT
;
1371 tree size
= TYPE_SIZE (type
);
1372 if (tree_fits_uhwi_p (size
))
1373 align
= tree_to_uhwi (size
);
1374 if (align
>= MAX_OFILE_ALIGNMENT
)
1375 return MAX_OFILE_ALIGNMENT
;
1376 return MAX (align
, GET_MODE_ALIGNMENT (TYPE_MODE (type
)));
1379 /* The default implementation of
1380 TARGET_VECTORIZE_PREFERRED_VECTOR_ALIGNMENT. */
1383 default_preferred_vector_alignment (const_tree type
)
1385 return TYPE_ALIGN (type
);
1388 /* By default assume vectors of element TYPE require a multiple of the natural
1389 alignment of TYPE. TYPE is naturally aligned if IS_PACKED is false. */
1391 default_builtin_vector_alignment_reachable (const_tree
/*type*/, bool is_packed
)
1396 /* By default, assume that a target supports any factor of misalignment
1397 memory access if it supports movmisalign patten.
1398 is_packed is true if the memory access is defined in a packed struct. */
1400 default_builtin_support_vector_misalignment (machine_mode mode
,
1408 if (optab_handler (movmisalign_optab
, mode
) != CODE_FOR_nothing
)
1413 /* By default, only attempt to parallelize bitwise operations, and
1414 possibly adds/subtracts using bit-twiddling. */
1417 default_preferred_simd_mode (scalar_mode
)
1422 /* By default do not split reductions further. */
1425 default_split_reduction (machine_mode mode
)
1430 /* By default only the preferred vector mode is tried. */
1433 default_autovectorize_vector_modes (vector_modes
*, bool)
1438 /* The default implementation of TARGET_VECTORIZE_RELATED_MODE. */
1441 default_vectorize_related_mode (machine_mode vector_mode
,
1442 scalar_mode element_mode
,
1445 machine_mode result_mode
;
1446 if ((maybe_ne (nunits
, 0U)
1447 || multiple_p (GET_MODE_SIZE (vector_mode
),
1448 GET_MODE_SIZE (element_mode
), &nunits
))
1449 && mode_for_vector (element_mode
, nunits
).exists (&result_mode
)
1450 && VECTOR_MODE_P (result_mode
)
1451 && targetm
.vector_mode_supported_p (result_mode
))
1454 return opt_machine_mode ();
1457 /* By default a vector of integers is used as a mask. */
1460 default_get_mask_mode (machine_mode mode
)
1462 return related_int_vector_mode (mode
);
1465 /* By default consider masked stores to be expensive. */
1468 default_empty_mask_is_expensive (unsigned ifn
)
1470 return ifn
== IFN_MASK_STORE
;
1473 /* By default, the cost model accumulates three separate costs (prologue,
1474 loop body, and epilogue) for a vectorized loop or block. So allocate an
1475 array of three unsigned ints, set it to zero, and return its address. */
1478 default_vectorize_create_costs (vec_info
*vinfo
, bool costing_for_scalar
)
1480 return new vector_costs (vinfo
, costing_for_scalar
);
1483 /* Determine whether or not a pointer mode is valid. Assume defaults
1484 of ptr_mode or Pmode - can be overridden. */
1486 default_valid_pointer_mode (scalar_int_mode mode
)
1488 return (mode
== ptr_mode
|| mode
== Pmode
);
1491 /* Determine whether the memory reference specified by REF may alias
1492 the C libraries errno location. */
1494 default_ref_may_alias_errno (ao_ref
*ref
)
1496 tree base
= ao_ref_base (ref
);
1497 /* The default implementation assumes the errno location is
1498 a declaration of type int or is always accessed via a
1499 pointer to int. We assume that accesses to errno are
1500 not deliberately obfuscated (even in conforming ways). */
1501 if (TYPE_UNSIGNED (TREE_TYPE (base
))
1502 || TYPE_MODE (TREE_TYPE (base
)) != TYPE_MODE (integer_type_node
))
1504 /* The default implementation assumes an errno location declaration
1505 is never defined in the current compilation unit and may not be
1506 aliased by a local variable. */
1508 && DECL_EXTERNAL (base
)
1509 && !TREE_STATIC (base
))
1511 else if (TREE_CODE (base
) == MEM_REF
1512 && TREE_CODE (TREE_OPERAND (base
, 0)) == SSA_NAME
)
1514 struct ptr_info_def
*pi
= SSA_NAME_PTR_INFO (TREE_OPERAND (base
, 0));
1515 return !pi
|| pi
->pt
.anything
|| pi
->pt
.nonlocal
;
1520 /* Return the mode for a pointer to a given ADDRSPACE,
1521 defaulting to ptr_mode for all address spaces. */
1524 default_addr_space_pointer_mode (addr_space_t addrspace ATTRIBUTE_UNUSED
)
1529 /* Return the mode for an address in a given ADDRSPACE,
1530 defaulting to Pmode for all address spaces. */
1533 default_addr_space_address_mode (addr_space_t addrspace ATTRIBUTE_UNUSED
)
1538 /* Named address space version of valid_pointer_mode.
1539 To match the above, the same modes apply to all address spaces. */
1542 default_addr_space_valid_pointer_mode (scalar_int_mode mode
,
1543 addr_space_t as ATTRIBUTE_UNUSED
)
1545 return targetm
.valid_pointer_mode (mode
);
1548 /* Some places still assume that all pointer or address modes are the
1549 standard Pmode and ptr_mode. These optimizations become invalid if
1550 the target actually supports multiple different modes. For now,
1551 we disable such optimizations on such targets, using this function. */
1554 target_default_pointer_address_modes_p (void)
1556 if (targetm
.addr_space
.address_mode
!= default_addr_space_address_mode
)
1558 if (targetm
.addr_space
.pointer_mode
!= default_addr_space_pointer_mode
)
1564 /* Named address space version of legitimate_address_p.
1565 By default, all address spaces have the same form. */
1568 default_addr_space_legitimate_address_p (machine_mode mode
, rtx mem
,
1570 addr_space_t as ATTRIBUTE_UNUSED
)
1572 return targetm
.legitimate_address_p (mode
, mem
, strict
);
1575 /* Named address space version of LEGITIMIZE_ADDRESS.
1576 By default, all address spaces have the same form. */
1579 default_addr_space_legitimize_address (rtx x
, rtx oldx
, machine_mode mode
,
1580 addr_space_t as ATTRIBUTE_UNUSED
)
1582 return targetm
.legitimize_address (x
, oldx
, mode
);
1585 /* The default hook for determining if one named address space is a subset of
1586 another and to return which address space to use as the common address
1590 default_addr_space_subset_p (addr_space_t subset
, addr_space_t superset
)
1592 return (subset
== superset
);
1595 /* The default hook for determining if 0 within a named address
1596 space is a valid address. */
1599 default_addr_space_zero_address_valid (addr_space_t as ATTRIBUTE_UNUSED
)
1604 /* The default hook for debugging the address space is to return the
1605 address space number to indicate DW_AT_address_class. */
1607 default_addr_space_debug (addr_space_t as
)
1612 /* The default hook implementation for TARGET_ADDR_SPACE_DIAGNOSE_USAGE.
1613 Don't complain about any address space. */
1616 default_addr_space_diagnose_usage (addr_space_t
, location_t
)
1621 /* The default hook for TARGET_ADDR_SPACE_CONVERT. This hook should never be
1622 called for targets with only a generic address space. */
1625 default_addr_space_convert (rtx op ATTRIBUTE_UNUSED
,
1626 tree from_type ATTRIBUTE_UNUSED
,
1627 tree to_type ATTRIBUTE_UNUSED
)
1632 /* The defualt implementation of TARGET_HARD_REGNO_NREGS. */
1635 default_hard_regno_nregs (unsigned int, machine_mode mode
)
1637 /* Targets with variable-sized modes must provide their own definition
1639 return CEIL (GET_MODE_SIZE (mode
).to_constant (), UNITS_PER_WORD
);
1643 default_hard_regno_scratch_ok (unsigned int regno ATTRIBUTE_UNUSED
)
1648 /* The default implementation of TARGET_MODE_DEPENDENT_ADDRESS_P. */
1651 default_mode_dependent_address_p (const_rtx addr ATTRIBUTE_UNUSED
,
1652 addr_space_t addrspace ATTRIBUTE_UNUSED
)
1657 extern bool default_new_address_profitable_p (rtx
, rtx
);
1660 /* The default implementation of TARGET_NEW_ADDRESS_PROFITABLE_P. */
1663 default_new_address_profitable_p (rtx memref ATTRIBUTE_UNUSED
,
1664 rtx_insn
*insn ATTRIBUTE_UNUSED
,
1665 rtx new_addr ATTRIBUTE_UNUSED
)
1671 default_target_option_valid_attribute_p (tree
ARG_UNUSED (fndecl
),
1672 tree
ARG_UNUSED (name
),
1673 tree
ARG_UNUSED (args
),
1674 int ARG_UNUSED (flags
))
1676 warning (OPT_Wattributes
,
1677 "target attribute is not supported on this machine");
1683 default_target_option_pragma_parse (tree
ARG_UNUSED (args
),
1684 tree
ARG_UNUSED (pop_target
))
1686 /* If args is NULL the caller is handle_pragma_pop_options (). In that case,
1687 emit no warning because "#pragma GCC pop_target" is valid on targets that
1688 do not have the "target" pragma. */
1690 warning (OPT_Wpragmas
,
1691 "%<#pragma GCC target%> is not supported for this machine");
1697 default_target_can_inline_p (tree caller
, tree callee
)
1699 tree callee_opts
= DECL_FUNCTION_SPECIFIC_TARGET (callee
);
1700 tree caller_opts
= DECL_FUNCTION_SPECIFIC_TARGET (caller
);
1702 callee_opts
= target_option_default_node
;
1704 caller_opts
= target_option_default_node
;
1706 /* If both caller and callee have attributes, assume that if the
1707 pointer is different, the two functions have different target
1708 options since build_target_option_node uses a hash table for the
1710 return callee_opts
== caller_opts
;
1713 /* By default, return false to not need to collect any target information
1714 for inlining. Target maintainer should re-define the hook if the
1715 target want to take advantage of it. */
1718 default_need_ipa_fn_target_info (const_tree
, unsigned int &)
1724 default_update_ipa_fn_target_info (unsigned int &, const gimple
*)
1729 /* If the machine does not have a case insn that compares the bounds,
1730 this means extra overhead for dispatch tables, which raises the
1731 threshold for using them. */
1734 default_case_values_threshold (void)
1736 return (targetm
.have_casesi () ? 4 : 5);
1740 default_have_conditional_execution (void)
1742 return HAVE_conditional_execution
;
1745 /* By default we assume that c99 functions are present at the runtime,
1746 but sincos is not. */
1748 default_libc_has_function (enum function_class fn_class
,
1749 tree type ATTRIBUTE_UNUSED
)
1751 if (fn_class
== function_c94
1752 || fn_class
== function_c99_misc
1753 || fn_class
== function_c99_math_complex
)
1759 /* By default assume that libc has not a fast implementation. */
1762 default_libc_has_fast_function (int fcode ATTRIBUTE_UNUSED
)
1768 gnu_libc_has_function (enum function_class fn_class ATTRIBUTE_UNUSED
,
1769 tree type ATTRIBUTE_UNUSED
)
1775 no_c99_libc_has_function (enum function_class fn_class ATTRIBUTE_UNUSED
,
1776 tree type ATTRIBUTE_UNUSED
)
1782 default_builtin_tm_load_store (tree
ARG_UNUSED (type
))
1787 /* Compute cost of moving registers to/from memory. */
1790 default_memory_move_cost (machine_mode mode ATTRIBUTE_UNUSED
,
1791 reg_class_t rclass ATTRIBUTE_UNUSED
,
1792 bool in ATTRIBUTE_UNUSED
)
1794 #ifndef MEMORY_MOVE_COST
1795 return (4 + memory_move_secondary_cost (mode
, (enum reg_class
) rclass
, in
));
1797 return MEMORY_MOVE_COST (MACRO_MODE (mode
), (enum reg_class
) rclass
, in
);
1801 /* Compute cost of moving data from a register of class FROM to one of
1805 default_register_move_cost (machine_mode mode ATTRIBUTE_UNUSED
,
1806 reg_class_t from ATTRIBUTE_UNUSED
,
1807 reg_class_t to ATTRIBUTE_UNUSED
)
1809 #ifndef REGISTER_MOVE_COST
1812 return REGISTER_MOVE_COST (MACRO_MODE (mode
),
1813 (enum reg_class
) from
, (enum reg_class
) to
);
1817 /* The default implementation of TARGET_SLOW_UNALIGNED_ACCESS. */
1820 default_slow_unaligned_access (machine_mode
, unsigned int)
1822 return STRICT_ALIGNMENT
;
1825 /* The default implementation of TARGET_ESTIMATED_POLY_VALUE. */
1828 default_estimated_poly_value (poly_int64 x
, poly_value_estimate_kind
)
1833 /* For hooks which use the MOVE_RATIO macro, this gives the legacy default
1834 behavior. SPEED_P is true if we are compiling for speed. */
1837 get_move_ratio (bool speed_p ATTRIBUTE_UNUSED
)
1839 unsigned int move_ratio
;
1841 move_ratio
= (unsigned int) MOVE_RATIO (speed_p
);
1843 #if defined (HAVE_cpymemqi) || defined (HAVE_cpymemhi) || defined (HAVE_cpymemsi) || defined (HAVE_cpymemdi) || defined (HAVE_cpymemti)
1845 #else /* No cpymem patterns, pick a default. */
1846 move_ratio
= ((speed_p
) ? 15 : 3);
1852 /* Return TRUE if the move_by_pieces/set_by_pieces infrastructure should be
1853 used; return FALSE if the cpymem/setmem optab should be expanded, or
1854 a call to memcpy emitted. */
1857 default_use_by_pieces_infrastructure_p (unsigned HOST_WIDE_INT size
,
1858 unsigned int alignment
,
1859 enum by_pieces_operation op
,
1862 unsigned int max_size
= 0;
1863 unsigned int ratio
= 0;
1867 case CLEAR_BY_PIECES
:
1868 max_size
= STORE_MAX_PIECES
;
1869 ratio
= CLEAR_RATIO (speed_p
);
1871 case MOVE_BY_PIECES
:
1872 max_size
= MOVE_MAX_PIECES
;
1873 ratio
= get_move_ratio (speed_p
);
1876 max_size
= STORE_MAX_PIECES
;
1877 ratio
= SET_RATIO (speed_p
);
1879 case STORE_BY_PIECES
:
1880 max_size
= STORE_MAX_PIECES
;
1881 ratio
= get_move_ratio (speed_p
);
1883 case COMPARE_BY_PIECES
:
1884 max_size
= COMPARE_MAX_PIECES
;
1885 /* Pick a likely default, just as in get_move_ratio. */
1886 ratio
= speed_p
? 15 : 3;
1890 return by_pieces_ninsns (size
, alignment
, max_size
+ 1, op
) < ratio
;
1893 /* This hook controls code generation for expanding a memcmp operation by
1894 pieces. Return 1 for the normal pattern of compare/jump after each pair
1895 of loads, or a higher number to reduce the number of branches. */
1898 default_compare_by_pieces_branch_ratio (machine_mode
)
1903 /* Helper for default_print_patchable_function_entry and other
1904 print_patchable_function_entry hook implementations. */
1907 default_print_patchable_function_entry_1 (FILE *file
,
1908 unsigned HOST_WIDE_INT
1913 const char *nop_templ
= 0;
1915 rtx_insn
*my_nop
= make_insn_raw (gen_nop ());
1917 /* We use the template alone, relying on the (currently sane) assumption
1918 that the NOP template does not have variable operands. */
1919 code_num
= recog_memoized (my_nop
);
1920 nop_templ
= get_insn_template (code_num
, my_nop
);
1922 if (record_p
&& targetm_common
.have_named_sections
)
1925 static int patch_area_number
;
1926 section
*previous_section
= in_section
;
1927 const char *asm_op
= integer_asm_op (POINTER_SIZE_UNITS
, false);
1929 gcc_assert (asm_op
!= NULL
);
1930 patch_area_number
++;
1931 ASM_GENERATE_INTERNAL_LABEL (buf
, "LPFE", patch_area_number
);
1933 switch_to_section (get_section ("__patchable_function_entries",
1934 flags
, current_function_decl
));
1935 assemble_align (POINTER_SIZE
);
1936 fputs (asm_op
, file
);
1937 assemble_name_raw (file
, buf
);
1940 switch_to_section (previous_section
);
1941 ASM_OUTPUT_LABEL (file
, buf
);
1945 for (i
= 0; i
< patch_area_size
; ++i
)
1946 output_asm_insn (nop_templ
, NULL
);
1949 /* Write PATCH_AREA_SIZE NOPs into the asm outfile FILE around a function
1950 entry. If RECORD_P is true and the target supports named sections,
1951 the location of the NOPs will be recorded in a special object section
1952 called "__patchable_function_entries". This routine may be called
1953 twice per function to put NOPs before and after the function
1957 default_print_patchable_function_entry (FILE *file
,
1958 unsigned HOST_WIDE_INT patch_area_size
,
1961 unsigned int flags
= SECTION_WRITE
| SECTION_RELRO
;
1962 if (HAVE_GAS_SECTION_LINK_ORDER
)
1963 flags
|= SECTION_LINK_ORDER
;
1964 default_print_patchable_function_entry_1 (file
, patch_area_size
, record_p
,
1969 default_profile_before_prologue (void)
1971 #ifdef PROFILE_BEFORE_PROLOGUE
1978 /* The default implementation of TARGET_PREFERRED_RELOAD_CLASS. */
1981 default_preferred_reload_class (rtx x ATTRIBUTE_UNUSED
,
1984 #ifdef PREFERRED_RELOAD_CLASS
1985 return (reg_class_t
) PREFERRED_RELOAD_CLASS (x
, (enum reg_class
) rclass
);
1991 /* The default implementation of TARGET_OUTPUT_PREFERRED_RELOAD_CLASS. */
1994 default_preferred_output_reload_class (rtx x ATTRIBUTE_UNUSED
,
2000 /* The default implementation of TARGET_PREFERRED_RENAME_CLASS. */
2002 default_preferred_rename_class (reg_class_t rclass ATTRIBUTE_UNUSED
)
2007 /* The default implementation of TARGET_CLASS_LIKELY_SPILLED_P. */
2010 default_class_likely_spilled_p (reg_class_t rclass
)
2012 return (reg_class_size
[(int) rclass
] == 1);
2015 /* The default implementation of TARGET_CLASS_MAX_NREGS. */
2018 default_class_max_nregs (reg_class_t rclass ATTRIBUTE_UNUSED
,
2019 machine_mode mode ATTRIBUTE_UNUSED
)
2021 #ifdef CLASS_MAX_NREGS
2022 return (unsigned char) CLASS_MAX_NREGS ((enum reg_class
) rclass
,
2025 /* Targets with variable-sized modes must provide their own definition
2027 unsigned int size
= GET_MODE_SIZE (mode
).to_constant ();
2028 return (size
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
2032 /* Determine the debugging unwind mechanism for the target. */
2034 enum unwind_info_type
2035 default_debug_unwind_info (void)
2037 /* If the target wants to force the use of dwarf2 unwind info, let it. */
2038 /* ??? Change all users to the hook, then poison this. */
2039 #ifdef DWARF2_FRAME_INFO
2040 if (DWARF2_FRAME_INFO
)
2044 /* Otherwise, only turn it on if dwarf2 debugging is enabled. */
2045 #ifdef DWARF2_DEBUGGING_INFO
2046 if (dwarf_debuginfo_p ())
2053 /* Targets that set NUM_POLY_INT_COEFFS to something greater than 1
2054 must define this hook. */
2057 default_dwarf_poly_indeterminate_value (unsigned int, unsigned int *, int *)
2062 /* Determine the correct mode for a Dwarf frame register that represents
2066 default_dwarf_frame_reg_mode (int regno
)
2068 machine_mode save_mode
= reg_raw_mode
[regno
];
2070 if (targetm
.hard_regno_call_part_clobbered (eh_edge_abi
.id (),
2072 save_mode
= choose_hard_reg_mode (regno
, 1, &eh_edge_abi
);
2076 /* To be used by targets where reg_raw_mode doesn't return the right
2077 mode for registers used in apply_builtin_return and apply_builtin_arg. */
2080 default_get_reg_raw_mode (int regno
)
2082 /* Targets must override this hook if the underlying register is
2084 return as_a
<fixed_size_mode
> (reg_raw_mode
[regno
]);
2087 /* Return true if a leaf function should stay leaf even with profiling
2091 default_keep_leaf_when_profiled ()
2096 /* Return true if the state of option OPTION should be stored in PCH files
2097 and checked by default_pch_valid_p. Store the option's current state
2101 option_affects_pch_p (int option
, struct cl_option_state
*state
)
2103 if ((cl_options
[option
].flags
& CL_TARGET
) == 0)
2105 if ((cl_options
[option
].flags
& CL_PCH_IGNORE
) != 0)
2107 if (option_flag_var (option
, &global_options
) == &target_flags
)
2108 if (targetm
.check_pch_target_flags
)
2110 return get_option_state (&global_options
, option
, state
);
2113 /* Default version of get_pch_validity.
2114 By default, every flag difference is fatal; that will be mostly right for
2115 most targets, but completely right for very few. */
2118 default_get_pch_validity (size_t *sz
)
2120 struct cl_option_state state
;
2125 if (targetm
.check_pch_target_flags
)
2126 *sz
+= sizeof (target_flags
);
2127 for (i
= 0; i
< cl_options_count
; i
++)
2128 if (option_affects_pch_p (i
, &state
))
2131 result
= r
= XNEWVEC (char, *sz
);
2135 if (targetm
.check_pch_target_flags
)
2137 memcpy (r
, &target_flags
, sizeof (target_flags
));
2138 r
+= sizeof (target_flags
);
2141 for (i
= 0; i
< cl_options_count
; i
++)
2142 if (option_affects_pch_p (i
, &state
))
2144 memcpy (r
, state
.data
, state
.size
);
2151 /* Return a message which says that a PCH file was created with a different
2152 setting of OPTION. */
2155 pch_option_mismatch (const char *option
)
2157 return xasprintf (_("created and used with differing settings of '%s'"),
2161 /* Default version of pch_valid_p. */
2164 default_pch_valid_p (const void *data_p
, size_t len ATTRIBUTE_UNUSED
)
2166 struct cl_option_state state
;
2167 const char *data
= (const char *)data_p
;
2170 /* -fpic and -fpie also usually make a PCH invalid. */
2171 if (data
[0] != flag_pic
)
2172 return _("created and used with different settings of %<-fpic%>");
2173 if (data
[1] != flag_pie
)
2174 return _("created and used with different settings of %<-fpie%>");
2177 /* Check target_flags. */
2178 if (targetm
.check_pch_target_flags
)
2183 memcpy (&tf
, data
, sizeof (target_flags
));
2184 data
+= sizeof (target_flags
);
2185 r
= targetm
.check_pch_target_flags (tf
);
2190 for (i
= 0; i
< cl_options_count
; i
++)
2191 if (option_affects_pch_p (i
, &state
))
2193 if (memcmp (data
, state
.data
, state
.size
) != 0)
2194 return pch_option_mismatch (cl_options
[i
].opt_text
);
2201 /* Default version of cstore_mode. */
2204 default_cstore_mode (enum insn_code icode
)
2206 return as_a
<scalar_int_mode
> (insn_data
[(int) icode
].operand
[0].mode
);
2209 /* Default version of member_type_forces_blk. */
2212 default_member_type_forces_blk (const_tree
, machine_mode
)
2217 /* Default version of canonicalize_comparison. */
2220 default_canonicalize_comparison (int *, rtx
*, rtx
*, bool)
2224 /* Default implementation of TARGET_ATOMIC_ASSIGN_EXPAND_FENV. */
2227 default_atomic_assign_expand_fenv (tree
*, tree
*, tree
*)
2231 #ifndef PAD_VARARGS_DOWN
2232 #define PAD_VARARGS_DOWN BYTES_BIG_ENDIAN
2235 /* Build an indirect-ref expression over the given TREE, which represents a
2236 piece of a va_arg() expansion. */
2238 build_va_arg_indirect_ref (tree addr
)
2240 addr
= build_simple_mem_ref_loc (EXPR_LOCATION (addr
), addr
);
2244 /* The "standard" implementation of va_arg: read the value from the
2245 current (padded) address and increment by the (padded) size. */
2248 std_gimplify_va_arg_expr (tree valist
, tree type
, gimple_seq
*pre_p
,
2251 tree addr
, t
, type_size
, rounded_size
, valist_tmp
;
2252 unsigned HOST_WIDE_INT align
, boundary
;
2255 /* All of the alignment and movement below is for args-grow-up machines.
2256 As of 2004, there are only 3 ARGS_GROW_DOWNWARD targets, and they all
2257 implement their own specialized gimplify_va_arg_expr routines. */
2258 if (ARGS_GROW_DOWNWARD
)
2261 indirect
= pass_va_arg_by_reference (type
);
2263 type
= build_pointer_type (type
);
2265 if (targetm
.calls
.split_complex_arg
2266 && TREE_CODE (type
) == COMPLEX_TYPE
2267 && targetm
.calls
.split_complex_arg (type
))
2269 tree real_part
, imag_part
;
2271 real_part
= std_gimplify_va_arg_expr (valist
,
2272 TREE_TYPE (type
), pre_p
, NULL
);
2273 real_part
= get_initialized_tmp_var (real_part
, pre_p
);
2275 imag_part
= std_gimplify_va_arg_expr (unshare_expr (valist
),
2276 TREE_TYPE (type
), pre_p
, NULL
);
2277 imag_part
= get_initialized_tmp_var (imag_part
, pre_p
);
2279 return build2 (COMPLEX_EXPR
, type
, real_part
, imag_part
);
2282 align
= PARM_BOUNDARY
/ BITS_PER_UNIT
;
2283 boundary
= targetm
.calls
.function_arg_boundary (TYPE_MODE (type
), type
);
2285 /* When we align parameter on stack for caller, if the parameter
2286 alignment is beyond MAX_SUPPORTED_STACK_ALIGNMENT, it will be
2287 aligned at MAX_SUPPORTED_STACK_ALIGNMENT. We will match callee
2288 here with caller. */
2289 if (boundary
> MAX_SUPPORTED_STACK_ALIGNMENT
)
2290 boundary
= MAX_SUPPORTED_STACK_ALIGNMENT
;
2292 boundary
/= BITS_PER_UNIT
;
2294 /* Hoist the valist value into a temporary for the moment. */
2295 valist_tmp
= get_initialized_tmp_var (valist
, pre_p
);
2297 /* va_list pointer is aligned to PARM_BOUNDARY. If argument actually
2298 requires greater alignment, we must perform dynamic alignment. */
2299 if (boundary
> align
2300 && !TYPE_EMPTY_P (type
)
2301 && !integer_zerop (TYPE_SIZE (type
)))
2303 t
= build2 (MODIFY_EXPR
, TREE_TYPE (valist
), valist_tmp
,
2304 fold_build_pointer_plus_hwi (valist_tmp
, boundary
- 1));
2305 gimplify_and_add (t
, pre_p
);
2307 t
= build2 (MODIFY_EXPR
, TREE_TYPE (valist
), valist_tmp
,
2308 fold_build2 (BIT_AND_EXPR
, TREE_TYPE (valist
),
2310 build_int_cst (TREE_TYPE (valist
), -boundary
)));
2311 gimplify_and_add (t
, pre_p
);
2316 /* If the actual alignment is less than the alignment of the type,
2317 adjust the type accordingly so that we don't assume strict alignment
2318 when dereferencing the pointer. */
2319 boundary
*= BITS_PER_UNIT
;
2320 if (boundary
< TYPE_ALIGN (type
))
2322 type
= build_variant_type_copy (type
);
2323 SET_TYPE_ALIGN (type
, boundary
);
2326 /* Compute the rounded size of the type. */
2327 type_size
= arg_size_in_bytes (type
);
2328 rounded_size
= round_up (type_size
, align
);
2330 /* Reduce rounded_size so it's sharable with the postqueue. */
2331 gimplify_expr (&rounded_size
, pre_p
, post_p
, is_gimple_val
, fb_rvalue
);
2335 if (PAD_VARARGS_DOWN
&& !integer_zerop (rounded_size
))
2337 /* Small args are padded downward. */
2338 t
= fold_build2_loc (input_location
, GT_EXPR
, sizetype
,
2339 rounded_size
, size_int (align
));
2340 t
= fold_build3 (COND_EXPR
, sizetype
, t
, size_zero_node
,
2341 size_binop (MINUS_EXPR
, rounded_size
, type_size
));
2342 addr
= fold_build_pointer_plus (addr
, t
);
2345 /* Compute new value for AP. */
2346 t
= fold_build_pointer_plus (valist_tmp
, rounded_size
);
2347 t
= build2 (MODIFY_EXPR
, TREE_TYPE (valist
), valist
, t
);
2348 gimplify_and_add (t
, pre_p
);
2350 addr
= fold_convert (build_pointer_type (type
), addr
);
2353 addr
= build_va_arg_indirect_ref (addr
);
2355 return build_va_arg_indirect_ref (addr
);
2358 /* An implementation of TARGET_CAN_USE_DOLOOP_P for targets that do
2359 not support nested low-overhead loops. */
2362 can_use_doloop_if_innermost (const widest_int
&, const widest_int
&,
2363 unsigned int loop_depth
, bool)
2365 return loop_depth
== 1;
2368 /* Default implementation of TARGET_OPTAB_SUPPORTED_P. */
2371 default_optab_supported_p (int, machine_mode
, machine_mode
, optimization_type
)
2376 /* Default implementation of TARGET_MAX_NOCE_IFCVT_SEQ_COST. */
2379 default_max_noce_ifcvt_seq_cost (edge e
)
2381 bool predictable_p
= predictable_edge_p (e
);
2385 if (OPTION_SET_P (param_max_rtl_if_conversion_predictable_cost
))
2386 return param_max_rtl_if_conversion_predictable_cost
;
2390 if (OPTION_SET_P (param_max_rtl_if_conversion_unpredictable_cost
))
2391 return param_max_rtl_if_conversion_unpredictable_cost
;
2394 return BRANCH_COST (true, predictable_p
) * COSTS_N_INSNS (3);
2397 /* Default implementation of TARGET_MIN_ARITHMETIC_PRECISION. */
2400 default_min_arithmetic_precision (void)
2402 return WORD_REGISTER_OPERATIONS
? BITS_PER_WORD
: BITS_PER_UNIT
;
2405 /* Default implementation of TARGET_C_EXCESS_PRECISION. */
2407 enum flt_eval_method
2408 default_excess_precision (enum excess_precision_type ATTRIBUTE_UNUSED
)
2410 return FLT_EVAL_METHOD_PROMOTE_TO_FLOAT
;
2413 /* Default implementation for
2414 TARGET_STACK_CLASH_PROTECTION_ALLOCA_PROBE_RANGE. */
2416 default_stack_clash_protection_alloca_probe_range (void)
2421 /* The default implementation of TARGET_EARLY_REMAT_MODES. */
2424 default_select_early_remat_modes (sbitmap
)
2428 /* The default implementation of TARGET_PREFERRED_ELSE_VALUE. */
2431 default_preferred_else_value (unsigned, tree type
, unsigned, tree
*)
2433 return build_zero_cst (type
);
2436 /* Default implementation of TARGET_HAVE_SPECULATION_SAFE_VALUE. */
2438 default_have_speculation_safe_value (bool active ATTRIBUTE_UNUSED
)
2440 #ifdef HAVE_speculation_barrier
2441 return active
? HAVE_speculation_barrier
: true;
2446 /* Alternative implementation of TARGET_HAVE_SPECULATION_SAFE_VALUE
2447 that can be used on targets that never have speculative execution. */
2449 speculation_safe_value_not_needed (bool active
)
2454 /* Default implementation of the speculation-safe-load builtin. This
2455 implementation simply copies val to result and generates a
2456 speculation_barrier insn, if such a pattern is defined. */
2458 default_speculation_safe_value (machine_mode mode ATTRIBUTE_UNUSED
,
2459 rtx result
, rtx val
,
2460 rtx failval ATTRIBUTE_UNUSED
)
2462 emit_move_insn (result
, val
);
2464 #ifdef HAVE_speculation_barrier
2465 /* Assume the target knows what it is doing: if it defines a
2466 speculation barrier, but it is not enabled, then assume that one
2468 if (HAVE_speculation_barrier
)
2469 emit_insn (gen_speculation_barrier ());
2475 /* How many bits to shift in order to access the tag bits.
2476 The default is to store the tag in the top 8 bits of a 64 bit pointer, hence
2477 shifting 56 bits will leave just the tag. */
2478 #define HWASAN_SHIFT (GET_MODE_PRECISION (Pmode) - 8)
2479 #define HWASAN_SHIFT_RTX GEN_INT (HWASAN_SHIFT)
2482 default_memtag_can_tag_addresses ()
2488 default_memtag_tag_size ()
2494 default_memtag_granule_size ()
2499 /* The default implementation of TARGET_MEMTAG_INSERT_RANDOM_TAG. */
2501 default_memtag_insert_random_tag (rtx untagged
, rtx target
)
2503 gcc_assert (param_hwasan_instrument_stack
);
2504 if (param_hwasan_random_frame_tag
)
2506 rtx fn
= init_one_libfunc ("__hwasan_generate_tag");
2507 rtx new_tag
= emit_library_call_value (fn
, NULL_RTX
, LCT_NORMAL
, QImode
);
2508 return targetm
.memtag
.set_tag (untagged
, new_tag
, target
);
2512 /* NOTE: The kernel API does not have __hwasan_generate_tag exposed.
2513 In the future we may add the option emit random tags with inline
2514 instrumentation instead of function calls. This would be the same
2515 between the kernel and userland. */
2520 /* The default implementation of TARGET_MEMTAG_ADD_TAG. */
2522 default_memtag_add_tag (rtx base
, poly_int64 offset
, uint8_t tag_offset
)
2524 /* Need to look into what the most efficient code sequence is.
2525 This is a code sequence that would be emitted *many* times, so we
2526 want it as small as possible.
2528 There are two places where tag overflow is a question:
2529 - Tagging the shadow stack.
2530 (both tagging and untagging).
2531 - Tagging addressable pointers.
2533 We need to ensure both behaviors are the same (i.e. that the tag that
2534 ends up in a pointer after "overflowing" the tag bits with a tag addition
2535 is the same that ends up in the shadow space).
2537 The aim is that the behavior of tag addition should follow modulo
2538 wrapping in both instances.
2540 The libhwasan code doesn't have any path that increments a pointer's tag,
2541 which means it has no opinion on what happens when a tag increment
2542 overflows (and hence we can choose our own behavior). */
2544 offset
+= ((uint64_t)tag_offset
<< HWASAN_SHIFT
);
2545 return plus_constant (Pmode
, base
, offset
);
2548 /* The default implementation of TARGET_MEMTAG_SET_TAG. */
2550 default_memtag_set_tag (rtx untagged
, rtx tag
, rtx target
)
2552 gcc_assert (GET_MODE (untagged
) == Pmode
&& GET_MODE (tag
) == QImode
);
2553 tag
= expand_simple_binop (Pmode
, ASHIFT
, tag
, HWASAN_SHIFT_RTX
, NULL_RTX
,
2554 /* unsignedp = */1, OPTAB_WIDEN
);
2555 rtx ret
= expand_simple_binop (Pmode
, IOR
, untagged
, tag
, target
,
2556 /* unsignedp = */1, OPTAB_DIRECT
);
2561 /* The default implementation of TARGET_MEMTAG_EXTRACT_TAG. */
2563 default_memtag_extract_tag (rtx tagged_pointer
, rtx target
)
2565 rtx tag
= expand_simple_binop (Pmode
, LSHIFTRT
, tagged_pointer
,
2566 HWASAN_SHIFT_RTX
, target
,
2569 rtx ret
= gen_lowpart (QImode
, tag
);
2574 /* The default implementation of TARGET_MEMTAG_UNTAGGED_POINTER. */
2576 default_memtag_untagged_pointer (rtx tagged_pointer
, rtx target
)
2578 rtx tag_mask
= gen_int_mode ((HOST_WIDE_INT_1U
<< HWASAN_SHIFT
) - 1, Pmode
);
2579 rtx untagged_base
= expand_simple_binop (Pmode
, AND
, tagged_pointer
,
2580 tag_mask
, target
, true,
2582 gcc_assert (untagged_base
);
2583 return untagged_base
;
2586 /* The default implementation of TARGET_GCOV_TYPE_SIZE. */
2588 default_gcov_type_size (void)
2590 return TYPE_PRECISION (long_long_integer_type_node
) > 32 ? 64 : 32;
2593 #include "gt-targhooks.h"