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.cc. */
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 /* Choose the mode and rtx to use to zero REGNO, storing tem in PMODE and
1021 PREGNO_RTX and returning TRUE if successful, otherwise returning FALSE. If
1022 the natural mode for REGNO doesn't work, attempt to group it with subsequent
1023 adjacent registers set in TOZERO. */
1026 zcur_select_mode_rtx (unsigned int regno
, machine_mode
*pmode
,
1027 rtx
*pregno_rtx
, HARD_REG_SET tozero
)
1029 rtx regno_rtx
= regno_reg_rtx
[regno
];
1030 machine_mode mode
= GET_MODE (regno_rtx
);
1032 /* If the natural mode doesn't work, try some wider mode. */
1033 if (!targetm
.hard_regno_mode_ok (regno
, mode
))
1037 !found
&& nregs
<= hard_regno_max_nregs
1038 && regno
+ nregs
<= FIRST_PSEUDO_REGISTER
1039 && TEST_HARD_REG_BIT (tozero
,
1043 mode
= choose_hard_reg_mode (regno
, nregs
, 0);
1044 if (mode
== E_VOIDmode
)
1046 gcc_checking_assert (targetm
.hard_regno_mode_ok (regno
, mode
));
1047 regno_rtx
= gen_rtx_REG (mode
, regno
);
1055 *pregno_rtx
= regno_rtx
;
1059 /* The default hook for TARGET_ZERO_CALL_USED_REGS. */
1062 default_zero_call_used_regs (HARD_REG_SET need_zeroed_hardregs
)
1064 gcc_assert (!hard_reg_set_empty_p (need_zeroed_hardregs
));
1066 HARD_REG_SET failed
;
1067 CLEAR_HARD_REG_SET (failed
);
1068 bool progress
= false;
1070 /* First, try to zero each register in need_zeroed_hardregs by
1071 loading a zero into it, taking note of any failures in
1073 for (unsigned int regno
= 0; regno
< FIRST_PSEUDO_REGISTER
; regno
++)
1074 if (TEST_HARD_REG_BIT (need_zeroed_hardregs
, regno
))
1076 rtx_insn
*last_insn
= get_last_insn ();
1080 if (!zcur_select_mode_rtx (regno
, &mode
, ®no_rtx
,
1081 need_zeroed_hardregs
))
1083 SET_HARD_REG_BIT (failed
, regno
);
1087 rtx zero
= CONST0_RTX (mode
);
1088 rtx_insn
*insn
= emit_move_insn (regno_rtx
, zero
);
1089 if (!valid_insn_p (insn
))
1091 SET_HARD_REG_BIT (failed
, regno
);
1092 delete_insns_since (last_insn
);
1097 regno
+= hard_regno_nregs (regno
, mode
) - 1;
1101 /* Now retry with copies from zeroed registers, as long as we've
1102 made some PROGRESS, and registers remain to be zeroed in
1104 while (progress
&& !hard_reg_set_empty_p (failed
))
1106 HARD_REG_SET retrying
= failed
;
1108 CLEAR_HARD_REG_SET (failed
);
1111 for (unsigned int regno
= 0; regno
< FIRST_PSEUDO_REGISTER
; regno
++)
1112 if (TEST_HARD_REG_BIT (retrying
, regno
))
1117 /* This might select registers we've already zeroed. If grouping
1118 with them is what it takes to get regno zeroed, so be it. */
1119 if (!zcur_select_mode_rtx (regno
, &mode
, ®no_rtx
,
1120 need_zeroed_hardregs
))
1122 SET_HARD_REG_BIT (failed
, regno
);
1126 bool success
= false;
1127 /* Look for a source. */
1128 for (unsigned int src
= 0; src
< FIRST_PSEUDO_REGISTER
; src
++)
1130 /* If SRC hasn't been zeroed (yet?), skip it. */
1131 if (! TEST_HARD_REG_BIT (need_zeroed_hardregs
, src
))
1133 if (TEST_HARD_REG_BIT (retrying
, src
))
1136 /* Check that SRC can hold MODE, and that any other
1137 registers needed to hold MODE in SRC have also been
1139 if (!targetm
.hard_regno_mode_ok (src
, mode
))
1141 unsigned n
= targetm
.hard_regno_nregs (src
, mode
);
1143 for (unsigned i
= 1; ok
&& i
< n
; i
++)
1144 ok
= (TEST_HARD_REG_BIT (need_zeroed_hardregs
, src
+ i
)
1145 && !TEST_HARD_REG_BIT (retrying
, src
+ i
));
1149 /* SRC is usable, try to copy from it. */
1150 rtx_insn
*last_insn
= get_last_insn ();
1151 rtx src_rtx
= gen_rtx_REG (mode
, src
);
1152 rtx_insn
*insn
= emit_move_insn (regno_rtx
, src_rtx
);
1153 if (!valid_insn_p (insn
))
1154 /* It didn't work, remove any inserts. We'll look
1156 delete_insns_since (last_insn
);
1159 /* We're done for REGNO. */
1165 /* If nothing worked for REGNO this round, mark it to be
1166 retried if we get another round. */
1168 SET_HARD_REG_BIT (failed
, regno
);
1171 /* Take note so as to enable another round if needed. */
1173 regno
+= hard_regno_nregs (regno
, mode
) - 1;
1178 /* If any register remained, report it. */
1181 static bool issued_error
;
1184 issued_error
= true;
1185 sorry ("%qs not supported on this target",
1186 "-fzero-call-used-regs");
1190 return need_zeroed_hardregs
;
1194 default_internal_arg_pointer (void)
1196 /* If the reg that the virtual arg pointer will be translated into is
1197 not a fixed reg or is the stack pointer, make a copy of the virtual
1198 arg pointer, and address parms via the copy. The frame pointer is
1199 considered fixed even though it is not marked as such. */
1200 if ((ARG_POINTER_REGNUM
== STACK_POINTER_REGNUM
1201 || ! (fixed_regs
[ARG_POINTER_REGNUM
]
1202 || ARG_POINTER_REGNUM
== FRAME_POINTER_REGNUM
)))
1203 return copy_to_reg (virtual_incoming_args_rtx
);
1205 return virtual_incoming_args_rtx
;
1209 default_static_chain (const_tree
ARG_UNUSED (fndecl_or_type
), bool incoming_p
)
1213 #ifdef STATIC_CHAIN_INCOMING_REGNUM
1214 return gen_rtx_REG (Pmode
, STATIC_CHAIN_INCOMING_REGNUM
);
1218 #ifdef STATIC_CHAIN_REGNUM
1219 return gen_rtx_REG (Pmode
, STATIC_CHAIN_REGNUM
);
1223 static bool issued_error
;
1226 issued_error
= true;
1227 sorry ("nested functions not supported on this target");
1230 /* It really doesn't matter what we return here, so long at it
1231 doesn't cause the rest of the compiler to crash. */
1232 return gen_rtx_MEM (Pmode
, stack_pointer_rtx
);
1237 default_trampoline_init (rtx
ARG_UNUSED (m_tramp
), tree
ARG_UNUSED (t_func
),
1238 rtx
ARG_UNUSED (r_chain
))
1240 sorry ("nested function trampolines not supported on this target");
1244 default_return_pops_args (tree
, tree
, poly_int64
)
1250 default_ira_change_pseudo_allocno_class (int regno ATTRIBUTE_UNUSED
,
1252 reg_class_t best_cl ATTRIBUTE_UNUSED
)
1258 default_lra_p (void)
1264 default_register_priority (int hard_regno ATTRIBUTE_UNUSED
)
1270 default_register_usage_leveling_p (void)
1276 default_different_addr_displacement_p (void)
1282 default_secondary_reload (bool in_p ATTRIBUTE_UNUSED
, rtx x ATTRIBUTE_UNUSED
,
1283 reg_class_t reload_class_i ATTRIBUTE_UNUSED
,
1284 machine_mode reload_mode ATTRIBUTE_UNUSED
,
1285 secondary_reload_info
*sri
)
1287 enum reg_class rclass
= NO_REGS
;
1288 enum reg_class reload_class
= (enum reg_class
) reload_class_i
;
1290 if (sri
->prev_sri
&& sri
->prev_sri
->t_icode
!= CODE_FOR_nothing
)
1292 sri
->icode
= sri
->prev_sri
->t_icode
;
1295 #ifdef SECONDARY_INPUT_RELOAD_CLASS
1297 rclass
= SECONDARY_INPUT_RELOAD_CLASS (reload_class
,
1298 MACRO_MODE (reload_mode
), x
);
1300 #ifdef SECONDARY_OUTPUT_RELOAD_CLASS
1302 rclass
= SECONDARY_OUTPUT_RELOAD_CLASS (reload_class
,
1303 MACRO_MODE (reload_mode
), x
);
1305 if (rclass
!= NO_REGS
)
1307 enum insn_code icode
1308 = direct_optab_handler (in_p
? reload_in_optab
: reload_out_optab
,
1311 if (icode
!= CODE_FOR_nothing
1312 && !insn_operand_matches (icode
, in_p
, x
))
1313 icode
= CODE_FOR_nothing
;
1314 else if (icode
!= CODE_FOR_nothing
)
1316 const char *insn_constraint
, *scratch_constraint
;
1317 enum reg_class insn_class
, scratch_class
;
1319 gcc_assert (insn_data
[(int) icode
].n_operands
== 3);
1320 insn_constraint
= insn_data
[(int) icode
].operand
[!in_p
].constraint
;
1321 if (!*insn_constraint
)
1322 insn_class
= ALL_REGS
;
1327 gcc_assert (*insn_constraint
== '=');
1330 insn_class
= (reg_class_for_constraint
1331 (lookup_constraint (insn_constraint
)));
1332 gcc_assert (insn_class
!= NO_REGS
);
1335 scratch_constraint
= insn_data
[(int) icode
].operand
[2].constraint
;
1336 /* The scratch register's constraint must start with "=&",
1337 except for an input reload, where only "=" is necessary,
1338 and where it might be beneficial to re-use registers from
1340 gcc_assert (scratch_constraint
[0] == '='
1341 && (in_p
|| scratch_constraint
[1] == '&'));
1342 scratch_constraint
++;
1343 if (*scratch_constraint
== '&')
1344 scratch_constraint
++;
1345 scratch_class
= (reg_class_for_constraint
1346 (lookup_constraint (scratch_constraint
)));
1348 if (reg_class_subset_p (reload_class
, insn_class
))
1350 gcc_assert (scratch_class
== rclass
);
1354 rclass
= insn_class
;
1357 if (rclass
== NO_REGS
)
1360 sri
->t_icode
= icode
;
1365 /* The default implementation of TARGET_SECONDARY_MEMORY_NEEDED_MODE. */
1368 default_secondary_memory_needed_mode (machine_mode mode
)
1370 if (!targetm
.lra_p ()
1371 && known_lt (GET_MODE_BITSIZE (mode
), BITS_PER_WORD
)
1372 && INTEGRAL_MODE_P (mode
))
1373 return mode_for_size (BITS_PER_WORD
, GET_MODE_CLASS (mode
), 0).require ();
1377 /* By default, if flag_pic is true, then neither local nor global relocs
1378 should be placed in readonly memory. */
1381 default_reloc_rw_mask (void)
1383 return flag_pic
? 3 : 0;
1386 /* By default, address diff vectors are generated
1387 for jump tables when flag_pic is true. */
1390 default_generate_pic_addr_diff_vec (void)
1395 /* By default, do no modification. */
1396 tree
default_mangle_decl_assembler_name (tree decl ATTRIBUTE_UNUSED
,
1402 /* The default implementation of TARGET_STATIC_RTX_ALIGNMENT. */
1405 default_static_rtx_alignment (machine_mode mode
)
1407 return GET_MODE_ALIGNMENT (mode
);
1410 /* The default implementation of TARGET_CONSTANT_ALIGNMENT. */
1413 default_constant_alignment (const_tree
, HOST_WIDE_INT align
)
1418 /* An implementation of TARGET_CONSTANT_ALIGNMENT that aligns strings
1419 to at least BITS_PER_WORD but otherwise makes no changes. */
1422 constant_alignment_word_strings (const_tree exp
, HOST_WIDE_INT align
)
1424 if (TREE_CODE (exp
) == STRING_CST
)
1425 return MAX (align
, BITS_PER_WORD
);
1429 /* Default to natural alignment for vector types, bounded by
1430 MAX_OFILE_ALIGNMENT. */
1433 default_vector_alignment (const_tree type
)
1435 unsigned HOST_WIDE_INT align
= MAX_OFILE_ALIGNMENT
;
1436 tree size
= TYPE_SIZE (type
);
1437 if (tree_fits_uhwi_p (size
))
1438 align
= tree_to_uhwi (size
);
1439 if (align
>= MAX_OFILE_ALIGNMENT
)
1440 return MAX_OFILE_ALIGNMENT
;
1441 return MAX (align
, GET_MODE_ALIGNMENT (TYPE_MODE (type
)));
1444 /* The default implementation of
1445 TARGET_VECTORIZE_PREFERRED_VECTOR_ALIGNMENT. */
1448 default_preferred_vector_alignment (const_tree type
)
1450 return TYPE_ALIGN (type
);
1453 /* By default assume vectors of element TYPE require a multiple of the natural
1454 alignment of TYPE. TYPE is naturally aligned if IS_PACKED is false. */
1456 default_builtin_vector_alignment_reachable (const_tree
/*type*/, bool is_packed
)
1461 /* By default, assume that a target supports any factor of misalignment
1462 memory access if it supports movmisalign patten.
1463 is_packed is true if the memory access is defined in a packed struct. */
1465 default_builtin_support_vector_misalignment (machine_mode mode
,
1473 if (optab_handler (movmisalign_optab
, mode
) != CODE_FOR_nothing
)
1478 /* By default, only attempt to parallelize bitwise operations, and
1479 possibly adds/subtracts using bit-twiddling. */
1482 default_preferred_simd_mode (scalar_mode
)
1487 /* By default do not split reductions further. */
1490 default_split_reduction (machine_mode mode
)
1495 /* By default only the preferred vector mode is tried. */
1498 default_autovectorize_vector_modes (vector_modes
*, bool)
1503 /* The default implementation of TARGET_VECTORIZE_RELATED_MODE. */
1506 default_vectorize_related_mode (machine_mode vector_mode
,
1507 scalar_mode element_mode
,
1510 machine_mode result_mode
;
1511 if ((maybe_ne (nunits
, 0U)
1512 || multiple_p (GET_MODE_SIZE (vector_mode
),
1513 GET_MODE_SIZE (element_mode
), &nunits
))
1514 && mode_for_vector (element_mode
, nunits
).exists (&result_mode
)
1515 && VECTOR_MODE_P (result_mode
)
1516 && targetm
.vector_mode_supported_p (result_mode
))
1519 return opt_machine_mode ();
1522 /* By default a vector of integers is used as a mask. */
1525 default_get_mask_mode (machine_mode mode
)
1527 return related_int_vector_mode (mode
);
1530 /* By default consider masked stores to be expensive. */
1533 default_empty_mask_is_expensive (unsigned ifn
)
1535 return ifn
== IFN_MASK_STORE
;
1538 /* By default, the cost model accumulates three separate costs (prologue,
1539 loop body, and epilogue) for a vectorized loop or block. So allocate an
1540 array of three unsigned ints, set it to zero, and return its address. */
1543 default_vectorize_create_costs (vec_info
*vinfo
, bool costing_for_scalar
)
1545 return new vector_costs (vinfo
, costing_for_scalar
);
1548 /* Determine whether or not a pointer mode is valid. Assume defaults
1549 of ptr_mode or Pmode - can be overridden. */
1551 default_valid_pointer_mode (scalar_int_mode mode
)
1553 return (mode
== ptr_mode
|| mode
== Pmode
);
1556 /* Determine whether the memory reference specified by REF may alias
1557 the C libraries errno location. */
1559 default_ref_may_alias_errno (ao_ref
*ref
)
1561 tree base
= ao_ref_base (ref
);
1562 /* The default implementation assumes the errno location is
1563 a declaration of type int or is always accessed via a
1564 pointer to int. We assume that accesses to errno are
1565 not deliberately obfuscated (even in conforming ways). */
1566 if (TYPE_UNSIGNED (TREE_TYPE (base
))
1567 || TYPE_MODE (TREE_TYPE (base
)) != TYPE_MODE (integer_type_node
))
1569 /* The default implementation assumes an errno location declaration
1570 is never defined in the current compilation unit and may not be
1571 aliased by a local variable. */
1573 && DECL_EXTERNAL (base
)
1574 && !TREE_STATIC (base
))
1576 else if (TREE_CODE (base
) == MEM_REF
1577 && TREE_CODE (TREE_OPERAND (base
, 0)) == SSA_NAME
)
1579 struct ptr_info_def
*pi
= SSA_NAME_PTR_INFO (TREE_OPERAND (base
, 0));
1580 return !pi
|| pi
->pt
.anything
|| pi
->pt
.nonlocal
;
1585 /* Return the mode for a pointer to a given ADDRSPACE,
1586 defaulting to ptr_mode for all address spaces. */
1589 default_addr_space_pointer_mode (addr_space_t addrspace ATTRIBUTE_UNUSED
)
1594 /* Return the mode for an address in a given ADDRSPACE,
1595 defaulting to Pmode for all address spaces. */
1598 default_addr_space_address_mode (addr_space_t addrspace ATTRIBUTE_UNUSED
)
1603 /* Named address space version of valid_pointer_mode.
1604 To match the above, the same modes apply to all address spaces. */
1607 default_addr_space_valid_pointer_mode (scalar_int_mode mode
,
1608 addr_space_t as ATTRIBUTE_UNUSED
)
1610 return targetm
.valid_pointer_mode (mode
);
1613 /* Some places still assume that all pointer or address modes are the
1614 standard Pmode and ptr_mode. These optimizations become invalid if
1615 the target actually supports multiple different modes. For now,
1616 we disable such optimizations on such targets, using this function. */
1619 target_default_pointer_address_modes_p (void)
1621 if (targetm
.addr_space
.address_mode
!= default_addr_space_address_mode
)
1623 if (targetm
.addr_space
.pointer_mode
!= default_addr_space_pointer_mode
)
1629 /* Named address space version of legitimate_address_p.
1630 By default, all address spaces have the same form. */
1633 default_addr_space_legitimate_address_p (machine_mode mode
, rtx mem
,
1635 addr_space_t as ATTRIBUTE_UNUSED
)
1637 return targetm
.legitimate_address_p (mode
, mem
, strict
);
1640 /* Named address space version of LEGITIMIZE_ADDRESS.
1641 By default, all address spaces have the same form. */
1644 default_addr_space_legitimize_address (rtx x
, rtx oldx
, machine_mode mode
,
1645 addr_space_t as ATTRIBUTE_UNUSED
)
1647 return targetm
.legitimize_address (x
, oldx
, mode
);
1650 /* The default hook for determining if one named address space is a subset of
1651 another and to return which address space to use as the common address
1655 default_addr_space_subset_p (addr_space_t subset
, addr_space_t superset
)
1657 return (subset
== superset
);
1660 /* The default hook for determining if 0 within a named address
1661 space is a valid address. */
1664 default_addr_space_zero_address_valid (addr_space_t as ATTRIBUTE_UNUSED
)
1669 /* The default hook for debugging the address space is to return the
1670 address space number to indicate DW_AT_address_class. */
1672 default_addr_space_debug (addr_space_t as
)
1677 /* The default hook implementation for TARGET_ADDR_SPACE_DIAGNOSE_USAGE.
1678 Don't complain about any address space. */
1681 default_addr_space_diagnose_usage (addr_space_t
, location_t
)
1686 /* The default hook for TARGET_ADDR_SPACE_CONVERT. This hook should never be
1687 called for targets with only a generic address space. */
1690 default_addr_space_convert (rtx op ATTRIBUTE_UNUSED
,
1691 tree from_type ATTRIBUTE_UNUSED
,
1692 tree to_type ATTRIBUTE_UNUSED
)
1697 /* The defualt implementation of TARGET_HARD_REGNO_NREGS. */
1700 default_hard_regno_nregs (unsigned int, machine_mode mode
)
1702 /* Targets with variable-sized modes must provide their own definition
1704 return CEIL (GET_MODE_SIZE (mode
).to_constant (), UNITS_PER_WORD
);
1708 default_hard_regno_scratch_ok (unsigned int regno ATTRIBUTE_UNUSED
)
1713 /* The default implementation of TARGET_MODE_DEPENDENT_ADDRESS_P. */
1716 default_mode_dependent_address_p (const_rtx addr ATTRIBUTE_UNUSED
,
1717 addr_space_t addrspace ATTRIBUTE_UNUSED
)
1722 extern bool default_new_address_profitable_p (rtx
, rtx
);
1725 /* The default implementation of TARGET_NEW_ADDRESS_PROFITABLE_P. */
1728 default_new_address_profitable_p (rtx memref ATTRIBUTE_UNUSED
,
1729 rtx_insn
*insn ATTRIBUTE_UNUSED
,
1730 rtx new_addr ATTRIBUTE_UNUSED
)
1736 default_target_option_valid_attribute_p (tree
ARG_UNUSED (fndecl
),
1737 tree
ARG_UNUSED (name
),
1738 tree
ARG_UNUSED (args
),
1739 int ARG_UNUSED (flags
))
1741 warning (OPT_Wattributes
,
1742 "target attribute is not supported on this machine");
1748 default_target_option_pragma_parse (tree
ARG_UNUSED (args
),
1749 tree
ARG_UNUSED (pop_target
))
1751 /* If args is NULL the caller is handle_pragma_pop_options (). In that case,
1752 emit no warning because "#pragma GCC pop_target" is valid on targets that
1753 do not have the "target" pragma. */
1755 warning (OPT_Wpragmas
,
1756 "%<#pragma GCC target%> is not supported for this machine");
1762 default_target_can_inline_p (tree caller
, tree callee
)
1764 tree callee_opts
= DECL_FUNCTION_SPECIFIC_TARGET (callee
);
1765 tree caller_opts
= DECL_FUNCTION_SPECIFIC_TARGET (caller
);
1767 callee_opts
= target_option_default_node
;
1769 caller_opts
= target_option_default_node
;
1771 /* If both caller and callee have attributes, assume that if the
1772 pointer is different, the two functions have different target
1773 options since build_target_option_node uses a hash table for the
1775 return callee_opts
== caller_opts
;
1778 /* By default, return false to not need to collect any target information
1779 for inlining. Target maintainer should re-define the hook if the
1780 target want to take advantage of it. */
1783 default_need_ipa_fn_target_info (const_tree
, unsigned int &)
1789 default_update_ipa_fn_target_info (unsigned int &, const gimple
*)
1794 /* If the machine does not have a case insn that compares the bounds,
1795 this means extra overhead for dispatch tables, which raises the
1796 threshold for using them. */
1799 default_case_values_threshold (void)
1801 return (targetm
.have_casesi () ? 4 : 5);
1805 default_have_conditional_execution (void)
1807 return HAVE_conditional_execution
;
1810 /* By default we assume that c99 functions are present at the runtime,
1811 but sincos is not. */
1813 default_libc_has_function (enum function_class fn_class
,
1814 tree type ATTRIBUTE_UNUSED
)
1816 if (fn_class
== function_c94
1817 || fn_class
== function_c99_misc
1818 || fn_class
== function_c99_math_complex
)
1824 /* By default assume that libc has not a fast implementation. */
1827 default_libc_has_fast_function (int fcode ATTRIBUTE_UNUSED
)
1833 gnu_libc_has_function (enum function_class fn_class ATTRIBUTE_UNUSED
,
1834 tree type ATTRIBUTE_UNUSED
)
1840 no_c99_libc_has_function (enum function_class fn_class ATTRIBUTE_UNUSED
,
1841 tree type ATTRIBUTE_UNUSED
)
1846 /* Assume some c99 functions are present at the runtime including sincos. */
1848 bsd_libc_has_function (enum function_class fn_class
,
1849 tree type ATTRIBUTE_UNUSED
)
1851 if (fn_class
== function_c94
1852 || fn_class
== function_c99_misc
1853 || fn_class
== function_sincos
)
1861 default_builtin_tm_load_store (tree
ARG_UNUSED (type
))
1866 /* Compute cost of moving registers to/from memory. */
1869 default_memory_move_cost (machine_mode mode ATTRIBUTE_UNUSED
,
1870 reg_class_t rclass ATTRIBUTE_UNUSED
,
1871 bool in ATTRIBUTE_UNUSED
)
1873 #ifndef MEMORY_MOVE_COST
1874 return (4 + memory_move_secondary_cost (mode
, (enum reg_class
) rclass
, in
));
1876 return MEMORY_MOVE_COST (MACRO_MODE (mode
), (enum reg_class
) rclass
, in
);
1880 /* Compute cost of moving data from a register of class FROM to one of
1884 default_register_move_cost (machine_mode mode ATTRIBUTE_UNUSED
,
1885 reg_class_t from ATTRIBUTE_UNUSED
,
1886 reg_class_t to ATTRIBUTE_UNUSED
)
1888 #ifndef REGISTER_MOVE_COST
1891 return REGISTER_MOVE_COST (MACRO_MODE (mode
),
1892 (enum reg_class
) from
, (enum reg_class
) to
);
1896 /* The default implementation of TARGET_SLOW_UNALIGNED_ACCESS. */
1899 default_slow_unaligned_access (machine_mode
, unsigned int)
1901 return STRICT_ALIGNMENT
;
1904 /* The default implementation of TARGET_ESTIMATED_POLY_VALUE. */
1907 default_estimated_poly_value (poly_int64 x
, poly_value_estimate_kind
)
1912 /* For hooks which use the MOVE_RATIO macro, this gives the legacy default
1913 behavior. SPEED_P is true if we are compiling for speed. */
1916 get_move_ratio (bool speed_p ATTRIBUTE_UNUSED
)
1918 unsigned int move_ratio
;
1920 move_ratio
= (unsigned int) MOVE_RATIO (speed_p
);
1922 #if defined (HAVE_cpymemqi) || defined (HAVE_cpymemhi) || defined (HAVE_cpymemsi) || defined (HAVE_cpymemdi) || defined (HAVE_cpymemti)
1924 #else /* No cpymem patterns, pick a default. */
1925 move_ratio
= ((speed_p
) ? 15 : 3);
1931 /* Return TRUE if the move_by_pieces/set_by_pieces infrastructure should be
1932 used; return FALSE if the cpymem/setmem optab should be expanded, or
1933 a call to memcpy emitted. */
1936 default_use_by_pieces_infrastructure_p (unsigned HOST_WIDE_INT size
,
1937 unsigned int alignment
,
1938 enum by_pieces_operation op
,
1941 unsigned int max_size
= 0;
1942 unsigned int ratio
= 0;
1946 case CLEAR_BY_PIECES
:
1947 max_size
= STORE_MAX_PIECES
;
1948 ratio
= CLEAR_RATIO (speed_p
);
1950 case MOVE_BY_PIECES
:
1951 max_size
= MOVE_MAX_PIECES
;
1952 ratio
= get_move_ratio (speed_p
);
1955 max_size
= STORE_MAX_PIECES
;
1956 ratio
= SET_RATIO (speed_p
);
1958 case STORE_BY_PIECES
:
1959 max_size
= STORE_MAX_PIECES
;
1960 ratio
= get_move_ratio (speed_p
);
1962 case COMPARE_BY_PIECES
:
1963 max_size
= COMPARE_MAX_PIECES
;
1964 /* Pick a likely default, just as in get_move_ratio. */
1965 ratio
= speed_p
? 15 : 3;
1969 return by_pieces_ninsns (size
, alignment
, max_size
+ 1, op
) < ratio
;
1972 /* This hook controls code generation for expanding a memcmp operation by
1973 pieces. Return 1 for the normal pattern of compare/jump after each pair
1974 of loads, or a higher number to reduce the number of branches. */
1977 default_compare_by_pieces_branch_ratio (machine_mode
)
1982 /* Helper for default_print_patchable_function_entry and other
1983 print_patchable_function_entry hook implementations. */
1986 default_print_patchable_function_entry_1 (FILE *file
,
1987 unsigned HOST_WIDE_INT
1992 const char *nop_templ
= 0;
1994 rtx_insn
*my_nop
= make_insn_raw (gen_nop ());
1996 /* We use the template alone, relying on the (currently sane) assumption
1997 that the NOP template does not have variable operands. */
1998 code_num
= recog_memoized (my_nop
);
1999 nop_templ
= get_insn_template (code_num
, my_nop
);
2001 if (record_p
&& targetm_common
.have_named_sections
)
2004 static int patch_area_number
;
2005 section
*previous_section
= in_section
;
2006 const char *asm_op
= integer_asm_op (POINTER_SIZE_UNITS
, false);
2008 gcc_assert (asm_op
!= NULL
);
2009 patch_area_number
++;
2010 ASM_GENERATE_INTERNAL_LABEL (buf
, "LPFE", patch_area_number
);
2012 switch_to_section (get_section ("__patchable_function_entries",
2013 flags
, current_function_decl
));
2014 assemble_align (POINTER_SIZE
);
2015 fputs (asm_op
, file
);
2016 assemble_name_raw (file
, buf
);
2019 switch_to_section (previous_section
);
2020 ASM_OUTPUT_LABEL (file
, buf
);
2024 for (i
= 0; i
< patch_area_size
; ++i
)
2025 output_asm_insn (nop_templ
, NULL
);
2028 /* Write PATCH_AREA_SIZE NOPs into the asm outfile FILE around a function
2029 entry. If RECORD_P is true and the target supports named sections,
2030 the location of the NOPs will be recorded in a special object section
2031 called "__patchable_function_entries". This routine may be called
2032 twice per function to put NOPs before and after the function
2036 default_print_patchable_function_entry (FILE *file
,
2037 unsigned HOST_WIDE_INT patch_area_size
,
2040 unsigned int flags
= SECTION_WRITE
| SECTION_RELRO
;
2041 if (HAVE_GAS_SECTION_LINK_ORDER
)
2042 flags
|= SECTION_LINK_ORDER
;
2043 default_print_patchable_function_entry_1 (file
, patch_area_size
, record_p
,
2048 default_profile_before_prologue (void)
2050 #ifdef PROFILE_BEFORE_PROLOGUE
2057 /* The default implementation of TARGET_PREFERRED_RELOAD_CLASS. */
2060 default_preferred_reload_class (rtx x ATTRIBUTE_UNUSED
,
2063 #ifdef PREFERRED_RELOAD_CLASS
2064 return (reg_class_t
) PREFERRED_RELOAD_CLASS (x
, (enum reg_class
) rclass
);
2070 /* The default implementation of TARGET_OUTPUT_PREFERRED_RELOAD_CLASS. */
2073 default_preferred_output_reload_class (rtx x ATTRIBUTE_UNUSED
,
2079 /* The default implementation of TARGET_PREFERRED_RENAME_CLASS. */
2081 default_preferred_rename_class (reg_class_t rclass ATTRIBUTE_UNUSED
)
2086 /* The default implementation of TARGET_CLASS_LIKELY_SPILLED_P. */
2089 default_class_likely_spilled_p (reg_class_t rclass
)
2091 return (reg_class_size
[(int) rclass
] == 1);
2094 /* The default implementation of TARGET_CLASS_MAX_NREGS. */
2097 default_class_max_nregs (reg_class_t rclass ATTRIBUTE_UNUSED
,
2098 machine_mode mode ATTRIBUTE_UNUSED
)
2100 #ifdef CLASS_MAX_NREGS
2101 return (unsigned char) CLASS_MAX_NREGS ((enum reg_class
) rclass
,
2104 /* Targets with variable-sized modes must provide their own definition
2106 unsigned int size
= GET_MODE_SIZE (mode
).to_constant ();
2107 return (size
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
2111 /* Determine the debugging unwind mechanism for the target. */
2113 enum unwind_info_type
2114 default_debug_unwind_info (void)
2116 /* If the target wants to force the use of dwarf2 unwind info, let it. */
2117 /* ??? Change all users to the hook, then poison this. */
2118 #ifdef DWARF2_FRAME_INFO
2119 if (DWARF2_FRAME_INFO
)
2123 /* Otherwise, only turn it on if dwarf2 debugging is enabled. */
2124 #ifdef DWARF2_DEBUGGING_INFO
2125 if (dwarf_debuginfo_p ())
2132 /* Targets that set NUM_POLY_INT_COEFFS to something greater than 1
2133 must define this hook. */
2136 default_dwarf_poly_indeterminate_value (unsigned int, unsigned int *, int *)
2141 /* Determine the correct mode for a Dwarf frame register that represents
2145 default_dwarf_frame_reg_mode (int regno
)
2147 machine_mode save_mode
= reg_raw_mode
[regno
];
2149 if (targetm
.hard_regno_call_part_clobbered (eh_edge_abi
.id (),
2151 save_mode
= choose_hard_reg_mode (regno
, 1, &eh_edge_abi
);
2155 /* To be used by targets where reg_raw_mode doesn't return the right
2156 mode for registers used in apply_builtin_return and apply_builtin_arg. */
2159 default_get_reg_raw_mode (int regno
)
2161 /* Targets must override this hook if the underlying register is
2163 return as_a
<fixed_size_mode
> (reg_raw_mode
[regno
]);
2166 /* Return true if a leaf function should stay leaf even with profiling
2170 default_keep_leaf_when_profiled ()
2175 /* Return true if the state of option OPTION should be stored in PCH files
2176 and checked by default_pch_valid_p. Store the option's current state
2180 option_affects_pch_p (int option
, struct cl_option_state
*state
)
2182 if ((cl_options
[option
].flags
& CL_TARGET
) == 0)
2184 if ((cl_options
[option
].flags
& CL_PCH_IGNORE
) != 0)
2186 if (option_flag_var (option
, &global_options
) == &target_flags
)
2187 if (targetm
.check_pch_target_flags
)
2189 return get_option_state (&global_options
, option
, state
);
2192 /* Default version of get_pch_validity.
2193 By default, every flag difference is fatal; that will be mostly right for
2194 most targets, but completely right for very few. */
2197 default_get_pch_validity (size_t *sz
)
2199 struct cl_option_state state
;
2204 if (targetm
.check_pch_target_flags
)
2205 *sz
+= sizeof (target_flags
);
2206 for (i
= 0; i
< cl_options_count
; i
++)
2207 if (option_affects_pch_p (i
, &state
))
2210 result
= r
= XNEWVEC (char, *sz
);
2214 if (targetm
.check_pch_target_flags
)
2216 memcpy (r
, &target_flags
, sizeof (target_flags
));
2217 r
+= sizeof (target_flags
);
2220 for (i
= 0; i
< cl_options_count
; i
++)
2221 if (option_affects_pch_p (i
, &state
))
2223 memcpy (r
, state
.data
, state
.size
);
2230 /* Return a message which says that a PCH file was created with a different
2231 setting of OPTION. */
2234 pch_option_mismatch (const char *option
)
2236 return xasprintf (_("created and used with differing settings of '%s'"),
2240 /* Default version of pch_valid_p. */
2243 default_pch_valid_p (const void *data_p
, size_t len ATTRIBUTE_UNUSED
)
2245 struct cl_option_state state
;
2246 const char *data
= (const char *)data_p
;
2249 /* -fpic and -fpie also usually make a PCH invalid. */
2250 if (data
[0] != flag_pic
)
2251 return _("created and used with different settings of %<-fpic%>");
2252 if (data
[1] != flag_pie
)
2253 return _("created and used with different settings of %<-fpie%>");
2256 /* Check target_flags. */
2257 if (targetm
.check_pch_target_flags
)
2262 memcpy (&tf
, data
, sizeof (target_flags
));
2263 data
+= sizeof (target_flags
);
2264 r
= targetm
.check_pch_target_flags (tf
);
2269 for (i
= 0; i
< cl_options_count
; i
++)
2270 if (option_affects_pch_p (i
, &state
))
2272 if (memcmp (data
, state
.data
, state
.size
) != 0)
2273 return pch_option_mismatch (cl_options
[i
].opt_text
);
2280 /* Default version of cstore_mode. */
2283 default_cstore_mode (enum insn_code icode
)
2285 return as_a
<scalar_int_mode
> (insn_data
[(int) icode
].operand
[0].mode
);
2288 /* Default version of member_type_forces_blk. */
2291 default_member_type_forces_blk (const_tree
, machine_mode
)
2296 /* Default version of canonicalize_comparison. */
2299 default_canonicalize_comparison (int *, rtx
*, rtx
*, bool)
2303 /* Default implementation of TARGET_ATOMIC_ASSIGN_EXPAND_FENV. */
2306 default_atomic_assign_expand_fenv (tree
*, tree
*, tree
*)
2310 #ifndef PAD_VARARGS_DOWN
2311 #define PAD_VARARGS_DOWN BYTES_BIG_ENDIAN
2314 /* Build an indirect-ref expression over the given TREE, which represents a
2315 piece of a va_arg() expansion. */
2317 build_va_arg_indirect_ref (tree addr
)
2319 addr
= build_simple_mem_ref_loc (EXPR_LOCATION (addr
), addr
);
2323 /* The "standard" implementation of va_arg: read the value from the
2324 current (padded) address and increment by the (padded) size. */
2327 std_gimplify_va_arg_expr (tree valist
, tree type
, gimple_seq
*pre_p
,
2330 tree addr
, t
, type_size
, rounded_size
, valist_tmp
;
2331 unsigned HOST_WIDE_INT align
, boundary
;
2334 /* All of the alignment and movement below is for args-grow-up machines.
2335 As of 2004, there are only 3 ARGS_GROW_DOWNWARD targets, and they all
2336 implement their own specialized gimplify_va_arg_expr routines. */
2337 if (ARGS_GROW_DOWNWARD
)
2340 indirect
= pass_va_arg_by_reference (type
);
2342 type
= build_pointer_type (type
);
2344 if (targetm
.calls
.split_complex_arg
2345 && TREE_CODE (type
) == COMPLEX_TYPE
2346 && targetm
.calls
.split_complex_arg (type
))
2348 tree real_part
, imag_part
;
2350 real_part
= std_gimplify_va_arg_expr (valist
,
2351 TREE_TYPE (type
), pre_p
, NULL
);
2352 real_part
= get_initialized_tmp_var (real_part
, pre_p
);
2354 imag_part
= std_gimplify_va_arg_expr (unshare_expr (valist
),
2355 TREE_TYPE (type
), pre_p
, NULL
);
2356 imag_part
= get_initialized_tmp_var (imag_part
, pre_p
);
2358 return build2 (COMPLEX_EXPR
, type
, real_part
, imag_part
);
2361 align
= PARM_BOUNDARY
/ BITS_PER_UNIT
;
2362 boundary
= targetm
.calls
.function_arg_boundary (TYPE_MODE (type
), type
);
2364 /* When we align parameter on stack for caller, if the parameter
2365 alignment is beyond MAX_SUPPORTED_STACK_ALIGNMENT, it will be
2366 aligned at MAX_SUPPORTED_STACK_ALIGNMENT. We will match callee
2367 here with caller. */
2368 if (boundary
> MAX_SUPPORTED_STACK_ALIGNMENT
)
2369 boundary
= MAX_SUPPORTED_STACK_ALIGNMENT
;
2371 boundary
/= BITS_PER_UNIT
;
2373 /* Hoist the valist value into a temporary for the moment. */
2374 valist_tmp
= get_initialized_tmp_var (valist
, pre_p
);
2376 /* va_list pointer is aligned to PARM_BOUNDARY. If argument actually
2377 requires greater alignment, we must perform dynamic alignment. */
2378 if (boundary
> align
2379 && !TYPE_EMPTY_P (type
)
2380 && !integer_zerop (TYPE_SIZE (type
)))
2382 t
= build2 (MODIFY_EXPR
, TREE_TYPE (valist
), valist_tmp
,
2383 fold_build_pointer_plus_hwi (valist_tmp
, boundary
- 1));
2384 gimplify_and_add (t
, pre_p
);
2386 t
= build2 (MODIFY_EXPR
, TREE_TYPE (valist
), valist_tmp
,
2387 fold_build2 (BIT_AND_EXPR
, TREE_TYPE (valist
),
2389 build_int_cst (TREE_TYPE (valist
), -boundary
)));
2390 gimplify_and_add (t
, pre_p
);
2395 /* If the actual alignment is less than the alignment of the type,
2396 adjust the type accordingly so that we don't assume strict alignment
2397 when dereferencing the pointer. */
2398 boundary
*= BITS_PER_UNIT
;
2399 if (boundary
< TYPE_ALIGN (type
))
2401 type
= build_variant_type_copy (type
);
2402 SET_TYPE_ALIGN (type
, boundary
);
2405 /* Compute the rounded size of the type. */
2406 type_size
= arg_size_in_bytes (type
);
2407 rounded_size
= round_up (type_size
, align
);
2409 /* Reduce rounded_size so it's sharable with the postqueue. */
2410 gimplify_expr (&rounded_size
, pre_p
, post_p
, is_gimple_val
, fb_rvalue
);
2414 if (PAD_VARARGS_DOWN
&& !integer_zerop (rounded_size
))
2416 /* Small args are padded downward. */
2417 t
= fold_build2_loc (input_location
, GT_EXPR
, sizetype
,
2418 rounded_size
, size_int (align
));
2419 t
= fold_build3 (COND_EXPR
, sizetype
, t
, size_zero_node
,
2420 size_binop (MINUS_EXPR
, rounded_size
, type_size
));
2421 addr
= fold_build_pointer_plus (addr
, t
);
2424 /* Compute new value for AP. */
2425 t
= fold_build_pointer_plus (valist_tmp
, rounded_size
);
2426 t
= build2 (MODIFY_EXPR
, TREE_TYPE (valist
), valist
, t
);
2427 gimplify_and_add (t
, pre_p
);
2429 addr
= fold_convert (build_pointer_type (type
), addr
);
2432 addr
= build_va_arg_indirect_ref (addr
);
2434 return build_va_arg_indirect_ref (addr
);
2437 /* An implementation of TARGET_CAN_USE_DOLOOP_P for targets that do
2438 not support nested low-overhead loops. */
2441 can_use_doloop_if_innermost (const widest_int
&, const widest_int
&,
2442 unsigned int loop_depth
, bool)
2444 return loop_depth
== 1;
2447 /* Default implementation of TARGET_OPTAB_SUPPORTED_P. */
2450 default_optab_supported_p (int, machine_mode
, machine_mode
, optimization_type
)
2455 /* Default implementation of TARGET_MAX_NOCE_IFCVT_SEQ_COST. */
2458 default_max_noce_ifcvt_seq_cost (edge e
)
2460 bool predictable_p
= predictable_edge_p (e
);
2464 if (OPTION_SET_P (param_max_rtl_if_conversion_predictable_cost
))
2465 return param_max_rtl_if_conversion_predictable_cost
;
2469 if (OPTION_SET_P (param_max_rtl_if_conversion_unpredictable_cost
))
2470 return param_max_rtl_if_conversion_unpredictable_cost
;
2473 return BRANCH_COST (true, predictable_p
) * COSTS_N_INSNS (3);
2476 /* Default implementation of TARGET_MIN_ARITHMETIC_PRECISION. */
2479 default_min_arithmetic_precision (void)
2481 return WORD_REGISTER_OPERATIONS
? BITS_PER_WORD
: BITS_PER_UNIT
;
2484 /* Default implementation of TARGET_C_EXCESS_PRECISION. */
2486 enum flt_eval_method
2487 default_excess_precision (enum excess_precision_type ATTRIBUTE_UNUSED
)
2489 return FLT_EVAL_METHOD_PROMOTE_TO_FLOAT
;
2492 /* Default implementation for
2493 TARGET_STACK_CLASH_PROTECTION_ALLOCA_PROBE_RANGE. */
2495 default_stack_clash_protection_alloca_probe_range (void)
2500 /* The default implementation of TARGET_EARLY_REMAT_MODES. */
2503 default_select_early_remat_modes (sbitmap
)
2507 /* The default implementation of TARGET_PREFERRED_ELSE_VALUE. */
2510 default_preferred_else_value (unsigned, tree type
, unsigned, tree
*)
2512 return build_zero_cst (type
);
2515 /* Default implementation of TARGET_HAVE_SPECULATION_SAFE_VALUE. */
2517 default_have_speculation_safe_value (bool active ATTRIBUTE_UNUSED
)
2519 #ifdef HAVE_speculation_barrier
2520 return active
? HAVE_speculation_barrier
: true;
2525 /* Alternative implementation of TARGET_HAVE_SPECULATION_SAFE_VALUE
2526 that can be used on targets that never have speculative execution. */
2528 speculation_safe_value_not_needed (bool active
)
2533 /* Default implementation of the speculation-safe-load builtin. This
2534 implementation simply copies val to result and generates a
2535 speculation_barrier insn, if such a pattern is defined. */
2537 default_speculation_safe_value (machine_mode mode ATTRIBUTE_UNUSED
,
2538 rtx result
, rtx val
,
2539 rtx failval ATTRIBUTE_UNUSED
)
2541 emit_move_insn (result
, val
);
2543 #ifdef HAVE_speculation_barrier
2544 /* Assume the target knows what it is doing: if it defines a
2545 speculation barrier, but it is not enabled, then assume that one
2547 if (HAVE_speculation_barrier
)
2548 emit_insn (gen_speculation_barrier ());
2554 /* How many bits to shift in order to access the tag bits.
2555 The default is to store the tag in the top 8 bits of a 64 bit pointer, hence
2556 shifting 56 bits will leave just the tag. */
2557 #define HWASAN_SHIFT (GET_MODE_PRECISION (Pmode) - 8)
2558 #define HWASAN_SHIFT_RTX GEN_INT (HWASAN_SHIFT)
2561 default_memtag_can_tag_addresses ()
2567 default_memtag_tag_size ()
2573 default_memtag_granule_size ()
2578 /* The default implementation of TARGET_MEMTAG_INSERT_RANDOM_TAG. */
2580 default_memtag_insert_random_tag (rtx untagged
, rtx target
)
2582 gcc_assert (param_hwasan_instrument_stack
);
2583 if (param_hwasan_random_frame_tag
)
2585 rtx fn
= init_one_libfunc ("__hwasan_generate_tag");
2586 rtx new_tag
= emit_library_call_value (fn
, NULL_RTX
, LCT_NORMAL
, QImode
);
2587 return targetm
.memtag
.set_tag (untagged
, new_tag
, target
);
2591 /* NOTE: The kernel API does not have __hwasan_generate_tag exposed.
2592 In the future we may add the option emit random tags with inline
2593 instrumentation instead of function calls. This would be the same
2594 between the kernel and userland. */
2599 /* The default implementation of TARGET_MEMTAG_ADD_TAG. */
2601 default_memtag_add_tag (rtx base
, poly_int64 offset
, uint8_t tag_offset
)
2603 /* Need to look into what the most efficient code sequence is.
2604 This is a code sequence that would be emitted *many* times, so we
2605 want it as small as possible.
2607 There are two places where tag overflow is a question:
2608 - Tagging the shadow stack.
2609 (both tagging and untagging).
2610 - Tagging addressable pointers.
2612 We need to ensure both behaviors are the same (i.e. that the tag that
2613 ends up in a pointer after "overflowing" the tag bits with a tag addition
2614 is the same that ends up in the shadow space).
2616 The aim is that the behavior of tag addition should follow modulo
2617 wrapping in both instances.
2619 The libhwasan code doesn't have any path that increments a pointer's tag,
2620 which means it has no opinion on what happens when a tag increment
2621 overflows (and hence we can choose our own behavior). */
2623 offset
+= ((uint64_t)tag_offset
<< HWASAN_SHIFT
);
2624 return plus_constant (Pmode
, base
, offset
);
2627 /* The default implementation of TARGET_MEMTAG_SET_TAG. */
2629 default_memtag_set_tag (rtx untagged
, rtx tag
, rtx target
)
2631 gcc_assert (GET_MODE (untagged
) == Pmode
&& GET_MODE (tag
) == QImode
);
2632 tag
= expand_simple_binop (Pmode
, ASHIFT
, tag
, HWASAN_SHIFT_RTX
, NULL_RTX
,
2633 /* unsignedp = */1, OPTAB_WIDEN
);
2634 rtx ret
= expand_simple_binop (Pmode
, IOR
, untagged
, tag
, target
,
2635 /* unsignedp = */1, OPTAB_DIRECT
);
2640 /* The default implementation of TARGET_MEMTAG_EXTRACT_TAG. */
2642 default_memtag_extract_tag (rtx tagged_pointer
, rtx target
)
2644 rtx tag
= expand_simple_binop (Pmode
, LSHIFTRT
, tagged_pointer
,
2645 HWASAN_SHIFT_RTX
, target
,
2648 rtx ret
= gen_lowpart (QImode
, tag
);
2653 /* The default implementation of TARGET_MEMTAG_UNTAGGED_POINTER. */
2655 default_memtag_untagged_pointer (rtx tagged_pointer
, rtx target
)
2657 rtx tag_mask
= gen_int_mode ((HOST_WIDE_INT_1U
<< HWASAN_SHIFT
) - 1, Pmode
);
2658 rtx untagged_base
= expand_simple_binop (Pmode
, AND
, tagged_pointer
,
2659 tag_mask
, target
, true,
2661 gcc_assert (untagged_base
);
2662 return untagged_base
;
2665 /* The default implementation of TARGET_GCOV_TYPE_SIZE. */
2667 default_gcov_type_size (void)
2669 return TYPE_PRECISION (long_long_integer_type_node
) > 32 ? 64 : 32;
2672 #include "gt-targhooks.h"