1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989-2021 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 #define INCLUDE_STRING
23 #include "coretypes.h"
32 #include "stringpool.h"
37 #include "diagnostic-core.h"
38 #include "fold-const.h"
39 #include "stor-layout.h"
41 #include "internal-fn.h"
47 #include "langhooks.h"
52 #include "tree-ssanames.h"
53 #include "tree-ssa-strlen.h"
55 #include "stringpool.h"
57 #include "hash-traits.h"
60 #include "gimple-fold.h"
61 #include "attr-fnspec.h"
62 #include "value-query.h"
64 #include "tree-pretty-print.h"
66 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
67 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
69 /* Data structure and subroutines used within expand_call. */
73 /* Tree node for this argument. */
75 /* Mode for value; TYPE_MODE unless promoted. */
77 /* Current RTL value for argument, or 0 if it isn't precomputed. */
79 /* Initially-compute RTL value for argument; only for const functions. */
81 /* Register to pass this argument in, 0 if passed on stack, or an
82 PARALLEL if the arg is to be copied into multiple non-contiguous
85 /* Register to pass this argument in when generating tail call sequence.
86 This is not the same register as for normal calls on machines with
89 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
90 form for emit_group_move. */
92 /* If REG was promoted from the actual mode of the argument expression,
93 indicates whether the promotion is sign- or zero-extended. */
95 /* Number of bytes to put in registers. 0 means put the whole arg
96 in registers. Also 0 if not passed in registers. */
98 /* Nonzero if argument must be passed on stack.
99 Note that some arguments may be passed on the stack
100 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
101 pass_on_stack identifies arguments that *cannot* go in registers. */
103 /* Some fields packaged up for locate_and_pad_parm. */
104 struct locate_and_pad_arg_data locate
;
105 /* Location on the stack at which parameter should be stored. The store
106 has already been done if STACK == VALUE. */
108 /* Location on the stack of the start of this argument slot. This can
109 differ from STACK if this arg pads downward. This location is known
110 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
112 /* Place that this stack area has been saved, if needed. */
114 /* If an argument's alignment does not permit direct copying into registers,
115 copy in smaller-sized pieces into pseudos. These are stored in a
116 block pointed to by this field. The next field says how many
117 word-sized pseudos we made. */
122 /* A vector of one char per byte of stack space. A byte if nonzero if
123 the corresponding stack location has been used.
124 This vector is used to prevent a function call within an argument from
125 clobbering any stack already set up. */
126 static char *stack_usage_map
;
128 /* Size of STACK_USAGE_MAP. */
129 static unsigned int highest_outgoing_arg_in_use
;
131 /* Assume that any stack location at this byte index is used,
132 without checking the contents of stack_usage_map. */
133 static unsigned HOST_WIDE_INT stack_usage_watermark
= HOST_WIDE_INT_M1U
;
135 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
136 stack location's tail call argument has been already stored into the stack.
137 This bitmap is used to prevent sibling call optimization if function tries
138 to use parent's incoming argument slots when they have been already
139 overwritten with tail call arguments. */
140 static sbitmap stored_args_map
;
142 /* Assume that any virtual-incoming location at this byte index has been
143 stored, without checking the contents of stored_args_map. */
144 static unsigned HOST_WIDE_INT stored_args_watermark
;
146 /* stack_arg_under_construction is nonzero when an argument may be
147 initialized with a constructor call (including a C function that
148 returns a BLKmode struct) and expand_call must take special action
149 to make sure the object being constructed does not overlap the
150 argument list for the constructor call. */
151 static int stack_arg_under_construction
;
153 static void precompute_register_parameters (int, struct arg_data
*, int *);
154 static int store_one_arg (struct arg_data
*, rtx
, int, int, int);
155 static void store_unaligned_arguments_into_pseudos (struct arg_data
*, int);
156 static int finalize_must_preallocate (int, int, struct arg_data
*,
158 static void precompute_arguments (int, struct arg_data
*);
159 static void compute_argument_addresses (struct arg_data
*, rtx
, int);
160 static rtx
rtx_for_function_call (tree
, tree
);
161 static void load_register_parameters (struct arg_data
*, int, rtx
*, int,
163 static int special_function_p (const_tree
, int);
164 static int check_sibcall_argument_overlap_1 (rtx
);
165 static int check_sibcall_argument_overlap (rtx_insn
*, struct arg_data
*, int);
167 static tree
split_complex_types (tree
);
169 #ifdef REG_PARM_STACK_SPACE
170 static rtx
save_fixed_argument_area (int, rtx
, int *, int *);
171 static void restore_fixed_argument_area (rtx
, rtx
, int, int);
174 /* Return true if bytes [LOWER_BOUND, UPPER_BOUND) of the outgoing
175 stack region might already be in use. */
178 stack_region_maybe_used_p (poly_uint64 lower_bound
, poly_uint64 upper_bound
,
179 unsigned int reg_parm_stack_space
)
181 unsigned HOST_WIDE_INT const_lower
, const_upper
;
182 const_lower
= constant_lower_bound (lower_bound
);
183 if (!upper_bound
.is_constant (&const_upper
))
184 const_upper
= HOST_WIDE_INT_M1U
;
186 if (const_upper
> stack_usage_watermark
)
189 /* Don't worry about things in the fixed argument area;
190 it has already been saved. */
191 const_lower
= MAX (const_lower
, reg_parm_stack_space
);
192 const_upper
= MIN (const_upper
, highest_outgoing_arg_in_use
);
193 for (unsigned HOST_WIDE_INT i
= const_lower
; i
< const_upper
; ++i
)
194 if (stack_usage_map
[i
])
199 /* Record that bytes [LOWER_BOUND, UPPER_BOUND) of the outgoing
200 stack region are now in use. */
203 mark_stack_region_used (poly_uint64 lower_bound
, poly_uint64 upper_bound
)
205 unsigned HOST_WIDE_INT const_lower
, const_upper
;
206 const_lower
= constant_lower_bound (lower_bound
);
207 if (upper_bound
.is_constant (&const_upper
))
208 for (unsigned HOST_WIDE_INT i
= const_lower
; i
< const_upper
; ++i
)
209 stack_usage_map
[i
] = 1;
211 stack_usage_watermark
= MIN (stack_usage_watermark
, const_lower
);
214 /* Force FUNEXP into a form suitable for the address of a CALL,
215 and return that as an rtx. Also load the static chain register
216 if FNDECL is a nested function.
218 CALL_FUSAGE points to a variable holding the prospective
219 CALL_INSN_FUNCTION_USAGE information. */
222 prepare_call_address (tree fndecl_or_type
, rtx funexp
, rtx static_chain_value
,
223 rtx
*call_fusage
, int reg_parm_seen
, int flags
)
225 /* Make a valid memory address and copy constants through pseudo-regs,
226 but not for a constant address if -fno-function-cse. */
227 if (GET_CODE (funexp
) != SYMBOL_REF
)
229 /* If it's an indirect call by descriptor, generate code to perform
230 runtime identification of the pointer and load the descriptor. */
231 if ((flags
& ECF_BY_DESCRIPTOR
) && !flag_trampolines
)
233 const int bit_val
= targetm
.calls
.custom_function_descriptors
;
234 rtx call_lab
= gen_label_rtx ();
236 gcc_assert (fndecl_or_type
&& TYPE_P (fndecl_or_type
));
238 = build_decl (UNKNOWN_LOCATION
, FUNCTION_DECL
, NULL_TREE
,
240 DECL_STATIC_CHAIN (fndecl_or_type
) = 1;
241 rtx chain
= targetm
.calls
.static_chain (fndecl_or_type
, false);
243 if (GET_MODE (funexp
) != Pmode
)
244 funexp
= convert_memory_address (Pmode
, funexp
);
246 /* Avoid long live ranges around function calls. */
247 funexp
= copy_to_mode_reg (Pmode
, funexp
);
250 emit_insn (gen_rtx_CLOBBER (VOIDmode
, chain
));
252 /* Emit the runtime identification pattern. */
253 rtx mask
= gen_rtx_AND (Pmode
, funexp
, GEN_INT (bit_val
));
254 emit_cmp_and_jump_insns (mask
, const0_rtx
, EQ
, NULL_RTX
, Pmode
, 1,
257 /* Statically predict the branch to very likely taken. */
258 rtx_insn
*insn
= get_last_insn ();
260 predict_insn_def (insn
, PRED_BUILTIN_EXPECT
, TAKEN
);
262 /* Load the descriptor. */
263 rtx mem
= gen_rtx_MEM (ptr_mode
,
264 plus_constant (Pmode
, funexp
, - bit_val
));
265 MEM_NOTRAP_P (mem
) = 1;
266 mem
= convert_memory_address (Pmode
, mem
);
267 emit_move_insn (chain
, mem
);
269 mem
= gen_rtx_MEM (ptr_mode
,
270 plus_constant (Pmode
, funexp
,
271 POINTER_SIZE
/ BITS_PER_UNIT
273 MEM_NOTRAP_P (mem
) = 1;
274 mem
= convert_memory_address (Pmode
, mem
);
275 emit_move_insn (funexp
, mem
);
277 emit_label (call_lab
);
281 use_reg (call_fusage
, chain
);
282 STATIC_CHAIN_REG_P (chain
) = 1;
285 /* Make sure we're not going to be overwritten below. */
286 gcc_assert (!static_chain_value
);
289 /* If we are using registers for parameters, force the
290 function address into a register now. */
291 funexp
= ((reg_parm_seen
292 && targetm
.small_register_classes_for_mode_p (FUNCTION_MODE
))
293 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
294 : memory_address (FUNCTION_MODE
, funexp
));
298 /* funexp could be a SYMBOL_REF represents a function pointer which is
299 of ptr_mode. In this case, it should be converted into address mode
300 to be a valid address for memory rtx pattern. See PR 64971. */
301 if (GET_MODE (funexp
) != Pmode
)
302 funexp
= convert_memory_address (Pmode
, funexp
);
304 if (!(flags
& ECF_SIBCALL
))
306 if (!NO_FUNCTION_CSE
&& optimize
&& ! flag_no_function_cse
)
307 funexp
= force_reg (Pmode
, funexp
);
311 if (static_chain_value
!= 0
312 && (TREE_CODE (fndecl_or_type
) != FUNCTION_DECL
313 || DECL_STATIC_CHAIN (fndecl_or_type
)))
317 chain
= targetm
.calls
.static_chain (fndecl_or_type
, false);
318 static_chain_value
= convert_memory_address (Pmode
, static_chain_value
);
320 emit_move_insn (chain
, static_chain_value
);
323 use_reg (call_fusage
, chain
);
324 STATIC_CHAIN_REG_P (chain
) = 1;
331 /* Generate instructions to call function FUNEXP,
332 and optionally pop the results.
333 The CALL_INSN is the first insn generated.
335 FNDECL is the declaration node of the function. This is given to the
336 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
339 FUNTYPE is the data type of the function. This is given to the hook
340 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
341 own args. We used to allow an identifier for library functions, but
342 that doesn't work when the return type is an aggregate type and the
343 calling convention says that the pointer to this aggregate is to be
344 popped by the callee.
346 STACK_SIZE is the number of bytes of arguments on the stack,
347 ROUNDED_STACK_SIZE is that number rounded up to
348 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
349 both to put into the call insn and to generate explicit popping
352 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
353 It is zero if this call doesn't want a structure value.
355 NEXT_ARG_REG is the rtx that results from executing
356 targetm.calls.function_arg (&args_so_far,
357 function_arg_info::end_marker ());
358 just after all the args have had their registers assigned.
359 This could be whatever you like, but normally it is the first
360 arg-register beyond those used for args in this call,
361 or 0 if all the arg-registers are used in this call.
362 It is passed on to `gen_call' so you can put this info in the call insn.
364 VALREG is a hard register in which a value is returned,
365 or 0 if the call does not return a value.
367 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
368 the args to this call were processed.
369 We restore `inhibit_defer_pop' to that value.
371 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
372 denote registers used by the called function. */
375 emit_call_1 (rtx funexp
, tree fntree ATTRIBUTE_UNUSED
, tree fndecl ATTRIBUTE_UNUSED
,
376 tree funtype ATTRIBUTE_UNUSED
,
377 poly_int64 stack_size ATTRIBUTE_UNUSED
,
378 poly_int64 rounded_stack_size
,
379 poly_int64 struct_value_size ATTRIBUTE_UNUSED
,
380 rtx next_arg_reg ATTRIBUTE_UNUSED
, rtx valreg
,
381 int old_inhibit_defer_pop
, rtx call_fusage
, int ecf_flags
,
382 cumulative_args_t args_so_far ATTRIBUTE_UNUSED
)
384 rtx rounded_stack_size_rtx
= gen_int_mode (rounded_stack_size
, Pmode
);
385 rtx call
, funmem
, pat
;
386 int already_popped
= 0;
387 poly_int64 n_popped
= 0;
389 /* Sibling call patterns never pop arguments (no sibcall(_value)_pop
390 patterns exist). Any popping that the callee does on return will
391 be from our caller's frame rather than ours. */
392 if (!(ecf_flags
& ECF_SIBCALL
))
394 n_popped
+= targetm
.calls
.return_pops_args (fndecl
, funtype
, stack_size
);
396 #ifdef CALL_POPS_ARGS
397 n_popped
+= CALL_POPS_ARGS (*get_cumulative_args (args_so_far
));
401 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
402 and we don't want to load it into a register as an optimization,
403 because prepare_call_address already did it if it should be done. */
404 if (GET_CODE (funexp
) != SYMBOL_REF
)
405 funexp
= memory_address (FUNCTION_MODE
, funexp
);
407 funmem
= gen_rtx_MEM (FUNCTION_MODE
, funexp
);
408 if (fndecl
&& TREE_CODE (fndecl
) == FUNCTION_DECL
)
412 /* Although a built-in FUNCTION_DECL and its non-__builtin
413 counterpart compare equal and get a shared mem_attrs, they
414 produce different dump output in compare-debug compilations,
415 if an entry gets garbage collected in one compilation, then
416 adds a different (but equivalent) entry, while the other
417 doesn't run the garbage collector at the same spot and then
418 shares the mem_attr with the equivalent entry. */
419 if (DECL_BUILT_IN_CLASS (t
) == BUILT_IN_NORMAL
)
421 tree t2
= builtin_decl_explicit (DECL_FUNCTION_CODE (t
));
426 set_mem_expr (funmem
, t
);
429 set_mem_expr (funmem
, build_simple_mem_ref (CALL_EXPR_FN (fntree
)));
431 if (ecf_flags
& ECF_SIBCALL
)
434 pat
= targetm
.gen_sibcall_value (valreg
, funmem
,
435 rounded_stack_size_rtx
,
436 next_arg_reg
, NULL_RTX
);
438 pat
= targetm
.gen_sibcall (funmem
, rounded_stack_size_rtx
,
440 gen_int_mode (struct_value_size
, Pmode
));
442 /* If the target has "call" or "call_value" insns, then prefer them
443 if no arguments are actually popped. If the target does not have
444 "call" or "call_value" insns, then we must use the popping versions
445 even if the call has no arguments to pop. */
446 else if (maybe_ne (n_popped
, 0)
448 ? targetm
.have_call_value ()
449 : targetm
.have_call ()))
451 rtx n_pop
= gen_int_mode (n_popped
, Pmode
);
453 /* If this subroutine pops its own args, record that in the call insn
454 if possible, for the sake of frame pointer elimination. */
457 pat
= targetm
.gen_call_value_pop (valreg
, funmem
,
458 rounded_stack_size_rtx
,
459 next_arg_reg
, n_pop
);
461 pat
= targetm
.gen_call_pop (funmem
, rounded_stack_size_rtx
,
462 next_arg_reg
, n_pop
);
469 pat
= targetm
.gen_call_value (valreg
, funmem
, rounded_stack_size_rtx
,
470 next_arg_reg
, NULL_RTX
);
472 pat
= targetm
.gen_call (funmem
, rounded_stack_size_rtx
, next_arg_reg
,
473 gen_int_mode (struct_value_size
, Pmode
));
477 /* Find the call we just emitted. */
478 rtx_call_insn
*call_insn
= last_call_insn ();
480 /* Some target create a fresh MEM instead of reusing the one provided
481 above. Set its MEM_EXPR. */
482 call
= get_call_rtx_from (call_insn
);
484 && MEM_EXPR (XEXP (call
, 0)) == NULL_TREE
485 && MEM_EXPR (funmem
) != NULL_TREE
)
486 set_mem_expr (XEXP (call
, 0), MEM_EXPR (funmem
));
488 /* Put the register usage information there. */
489 add_function_usage_to (call_insn
, call_fusage
);
491 /* If this is a const call, then set the insn's unchanging bit. */
492 if (ecf_flags
& ECF_CONST
)
493 RTL_CONST_CALL_P (call_insn
) = 1;
495 /* If this is a pure call, then set the insn's unchanging bit. */
496 if (ecf_flags
& ECF_PURE
)
497 RTL_PURE_CALL_P (call_insn
) = 1;
499 /* If this is a const call, then set the insn's unchanging bit. */
500 if (ecf_flags
& ECF_LOOPING_CONST_OR_PURE
)
501 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn
) = 1;
503 /* Create a nothrow REG_EH_REGION note, if needed. */
504 make_reg_eh_region_note (call_insn
, ecf_flags
, 0);
506 if (ecf_flags
& ECF_NORETURN
)
507 add_reg_note (call_insn
, REG_NORETURN
, const0_rtx
);
509 if (ecf_flags
& ECF_RETURNS_TWICE
)
511 add_reg_note (call_insn
, REG_SETJMP
, const0_rtx
);
512 cfun
->calls_setjmp
= 1;
515 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
517 /* Restore this now, so that we do defer pops for this call's args
518 if the context of the call as a whole permits. */
519 inhibit_defer_pop
= old_inhibit_defer_pop
;
521 if (maybe_ne (n_popped
, 0))
524 CALL_INSN_FUNCTION_USAGE (call_insn
)
525 = gen_rtx_EXPR_LIST (VOIDmode
,
526 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
527 CALL_INSN_FUNCTION_USAGE (call_insn
));
528 rounded_stack_size
-= n_popped
;
529 rounded_stack_size_rtx
= gen_int_mode (rounded_stack_size
, Pmode
);
530 stack_pointer_delta
-= n_popped
;
532 add_args_size_note (call_insn
, stack_pointer_delta
);
534 /* If popup is needed, stack realign must use DRAP */
535 if (SUPPORTS_STACK_ALIGNMENT
)
536 crtl
->need_drap
= true;
538 /* For noreturn calls when not accumulating outgoing args force
539 REG_ARGS_SIZE note to prevent crossjumping of calls with different
541 else if (!ACCUMULATE_OUTGOING_ARGS
&& (ecf_flags
& ECF_NORETURN
) != 0)
542 add_args_size_note (call_insn
, stack_pointer_delta
);
544 if (!ACCUMULATE_OUTGOING_ARGS
)
546 /* If returning from the subroutine does not automatically pop the args,
547 we need an instruction to pop them sooner or later.
548 Perhaps do it now; perhaps just record how much space to pop later.
550 If returning from the subroutine does pop the args, indicate that the
551 stack pointer will be changed. */
553 if (maybe_ne (rounded_stack_size
, 0))
555 if (ecf_flags
& ECF_NORETURN
)
556 /* Just pretend we did the pop. */
557 stack_pointer_delta
-= rounded_stack_size
;
558 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
559 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
560 pending_stack_adjust
+= rounded_stack_size
;
562 adjust_stack (rounded_stack_size_rtx
);
565 /* When we accumulate outgoing args, we must avoid any stack manipulations.
566 Restore the stack pointer to its original value now. Usually
567 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
568 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
569 popping variants of functions exist as well.
571 ??? We may optimize similar to defer_pop above, but it is
572 probably not worthwhile.
574 ??? It will be worthwhile to enable combine_stack_adjustments even for
576 else if (maybe_ne (n_popped
, 0))
577 anti_adjust_stack (gen_int_mode (n_popped
, Pmode
));
580 /* Determine if the function identified by FNDECL is one with
581 special properties we wish to know about. Modify FLAGS accordingly.
583 For example, if the function might return more than one time (setjmp), then
584 set ECF_RETURNS_TWICE.
586 Set ECF_MAY_BE_ALLOCA for any memory allocation function that might allocate
587 space from the stack such as alloca. */
590 special_function_p (const_tree fndecl
, int flags
)
592 tree name_decl
= DECL_NAME (fndecl
);
594 if (maybe_special_function_p (fndecl
)
595 && IDENTIFIER_LENGTH (name_decl
) <= 11)
597 const char *name
= IDENTIFIER_POINTER (name_decl
);
598 const char *tname
= name
;
600 /* We assume that alloca will always be called by name. It
601 makes no sense to pass it as a pointer-to-function to
602 anything that does not understand its behavior. */
603 if (IDENTIFIER_LENGTH (name_decl
) == 6
605 && ! strcmp (name
, "alloca"))
606 flags
|= ECF_MAY_BE_ALLOCA
;
608 /* Disregard prefix _ or __. */
617 /* ECF_RETURNS_TWICE is safe even for -ffreestanding. */
618 if (! strcmp (tname
, "setjmp")
619 || ! strcmp (tname
, "sigsetjmp")
620 || ! strcmp (name
, "savectx")
621 || ! strcmp (name
, "vfork")
622 || ! strcmp (name
, "getcontext"))
623 flags
|= ECF_RETURNS_TWICE
;
626 if (DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
627 && ALLOCA_FUNCTION_CODE_P (DECL_FUNCTION_CODE (fndecl
)))
628 flags
|= ECF_MAY_BE_ALLOCA
;
633 /* Return fnspec for DECL. */
636 decl_fnspec (tree fndecl
)
639 tree type
= TREE_TYPE (fndecl
);
642 attr
= lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type
));
645 return TREE_VALUE (TREE_VALUE (attr
));
648 if (fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
649 return builtin_fnspec (fndecl
);
653 /* Similar to special_function_p; return a set of ERF_ flags for the
656 decl_return_flags (tree fndecl
)
658 attr_fnspec fnspec
= decl_fnspec (fndecl
);
661 if (fnspec
.returns_arg (&arg
))
662 return ERF_RETURNS_ARG
| arg
;
664 if (fnspec
.returns_noalias_p ())
669 /* Return nonzero when FNDECL represents a call to setjmp. */
672 setjmp_call_p (const_tree fndecl
)
674 if (DECL_IS_RETURNS_TWICE (fndecl
))
675 return ECF_RETURNS_TWICE
;
676 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
680 /* Return true if STMT may be an alloca call. */
683 gimple_maybe_alloca_call_p (const gimple
*stmt
)
687 if (!is_gimple_call (stmt
))
690 fndecl
= gimple_call_fndecl (stmt
);
691 if (fndecl
&& (special_function_p (fndecl
, 0) & ECF_MAY_BE_ALLOCA
))
697 /* Return true if STMT is a builtin alloca call. */
700 gimple_alloca_call_p (const gimple
*stmt
)
704 if (!is_gimple_call (stmt
))
707 fndecl
= gimple_call_fndecl (stmt
);
708 if (fndecl
&& fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
709 switch (DECL_FUNCTION_CODE (fndecl
))
711 CASE_BUILT_IN_ALLOCA
:
712 return gimple_call_num_args (stmt
) > 0;
720 /* Return true when exp contains a builtin alloca call. */
723 alloca_call_p (const_tree exp
)
726 if (TREE_CODE (exp
) == CALL_EXPR
727 && (fndecl
= get_callee_fndecl (exp
))
728 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
729 switch (DECL_FUNCTION_CODE (fndecl
))
731 CASE_BUILT_IN_ALLOCA
:
740 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
741 function. Return FALSE otherwise. */
744 is_tm_builtin (const_tree fndecl
)
749 if (decl_is_tm_clone (fndecl
))
752 if (DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
754 switch (DECL_FUNCTION_CODE (fndecl
))
756 case BUILT_IN_TM_COMMIT
:
757 case BUILT_IN_TM_COMMIT_EH
:
758 case BUILT_IN_TM_ABORT
:
759 case BUILT_IN_TM_IRREVOCABLE
:
760 case BUILT_IN_TM_GETTMCLONE_IRR
:
761 case BUILT_IN_TM_MEMCPY
:
762 case BUILT_IN_TM_MEMMOVE
:
763 case BUILT_IN_TM_MEMSET
:
764 CASE_BUILT_IN_TM_STORE (1):
765 CASE_BUILT_IN_TM_STORE (2):
766 CASE_BUILT_IN_TM_STORE (4):
767 CASE_BUILT_IN_TM_STORE (8):
768 CASE_BUILT_IN_TM_STORE (FLOAT
):
769 CASE_BUILT_IN_TM_STORE (DOUBLE
):
770 CASE_BUILT_IN_TM_STORE (LDOUBLE
):
771 CASE_BUILT_IN_TM_STORE (M64
):
772 CASE_BUILT_IN_TM_STORE (M128
):
773 CASE_BUILT_IN_TM_STORE (M256
):
774 CASE_BUILT_IN_TM_LOAD (1):
775 CASE_BUILT_IN_TM_LOAD (2):
776 CASE_BUILT_IN_TM_LOAD (4):
777 CASE_BUILT_IN_TM_LOAD (8):
778 CASE_BUILT_IN_TM_LOAD (FLOAT
):
779 CASE_BUILT_IN_TM_LOAD (DOUBLE
):
780 CASE_BUILT_IN_TM_LOAD (LDOUBLE
):
781 CASE_BUILT_IN_TM_LOAD (M64
):
782 CASE_BUILT_IN_TM_LOAD (M128
):
783 CASE_BUILT_IN_TM_LOAD (M256
):
784 case BUILT_IN_TM_LOG
:
785 case BUILT_IN_TM_LOG_1
:
786 case BUILT_IN_TM_LOG_2
:
787 case BUILT_IN_TM_LOG_4
:
788 case BUILT_IN_TM_LOG_8
:
789 case BUILT_IN_TM_LOG_FLOAT
:
790 case BUILT_IN_TM_LOG_DOUBLE
:
791 case BUILT_IN_TM_LOG_LDOUBLE
:
792 case BUILT_IN_TM_LOG_M64
:
793 case BUILT_IN_TM_LOG_M128
:
794 case BUILT_IN_TM_LOG_M256
:
803 /* Detect flags (function attributes) from the function decl or type node. */
806 flags_from_decl_or_type (const_tree exp
)
812 /* The function exp may have the `malloc' attribute. */
813 if (DECL_IS_MALLOC (exp
))
816 /* The function exp may have the `returns_twice' attribute. */
817 if (DECL_IS_RETURNS_TWICE (exp
))
818 flags
|= ECF_RETURNS_TWICE
;
820 /* Process the pure and const attributes. */
821 if (TREE_READONLY (exp
))
823 if (DECL_PURE_P (exp
))
825 if (DECL_LOOPING_CONST_OR_PURE_P (exp
))
826 flags
|= ECF_LOOPING_CONST_OR_PURE
;
828 if (DECL_IS_NOVOPS (exp
))
830 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp
)))
832 if (lookup_attribute ("cold", DECL_ATTRIBUTES (exp
)))
835 if (TREE_NOTHROW (exp
))
836 flags
|= ECF_NOTHROW
;
840 if (is_tm_builtin (exp
))
841 flags
|= ECF_TM_BUILTIN
;
842 else if ((flags
& (ECF_CONST
|ECF_NOVOPS
)) != 0
843 || lookup_attribute ("transaction_pure",
844 TYPE_ATTRIBUTES (TREE_TYPE (exp
))))
845 flags
|= ECF_TM_PURE
;
848 flags
= special_function_p (exp
, flags
);
850 else if (TYPE_P (exp
))
852 if (TYPE_READONLY (exp
))
856 && ((flags
& ECF_CONST
) != 0
857 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp
))))
858 flags
|= ECF_TM_PURE
;
863 if (TREE_THIS_VOLATILE (exp
))
865 flags
|= ECF_NORETURN
;
866 if (flags
& (ECF_CONST
|ECF_PURE
))
867 flags
|= ECF_LOOPING_CONST_OR_PURE
;
873 /* Detect flags from a CALL_EXPR. */
876 call_expr_flags (const_tree t
)
879 tree decl
= get_callee_fndecl (t
);
882 flags
= flags_from_decl_or_type (decl
);
883 else if (CALL_EXPR_FN (t
) == NULL_TREE
)
884 flags
= internal_fn_flags (CALL_EXPR_IFN (t
));
887 tree type
= TREE_TYPE (CALL_EXPR_FN (t
));
888 if (type
&& TREE_CODE (type
) == POINTER_TYPE
)
889 flags
= flags_from_decl_or_type (TREE_TYPE (type
));
892 if (CALL_EXPR_BY_DESCRIPTOR (t
))
893 flags
|= ECF_BY_DESCRIPTOR
;
899 /* Return true if ARG should be passed by invisible reference. */
902 pass_by_reference (CUMULATIVE_ARGS
*ca
, function_arg_info arg
)
904 if (tree type
= arg
.type
)
906 /* If this type contains non-trivial constructors, then it is
907 forbidden for the middle-end to create any new copies. */
908 if (TREE_ADDRESSABLE (type
))
911 /* GCC post 3.4 passes *all* variable sized types by reference. */
912 if (!TYPE_SIZE (type
) || !poly_int_tree_p (TYPE_SIZE (type
)))
915 /* If a record type should be passed the same as its first (and only)
916 member, use the type and mode of that member. */
917 if (TREE_CODE (type
) == RECORD_TYPE
&& TYPE_TRANSPARENT_AGGR (type
))
919 arg
.type
= TREE_TYPE (first_field (type
));
920 arg
.mode
= TYPE_MODE (arg
.type
);
924 return targetm
.calls
.pass_by_reference (pack_cumulative_args (ca
), arg
);
927 /* Return true if TYPE should be passed by reference when passed to
928 the "..." arguments of a function. */
931 pass_va_arg_by_reference (tree type
)
933 return pass_by_reference (NULL
, function_arg_info (type
, /*named=*/false));
936 /* Decide whether ARG, which occurs in the state described by CA,
937 should be passed by reference. Return true if so and update
941 apply_pass_by_reference_rules (CUMULATIVE_ARGS
*ca
, function_arg_info
&arg
)
943 if (pass_by_reference (ca
, arg
))
945 arg
.type
= build_pointer_type (arg
.type
);
946 arg
.mode
= TYPE_MODE (arg
.type
);
947 arg
.pass_by_reference
= true;
953 /* Return true if ARG, which is passed by reference, should be callee
954 copied instead of caller copied. */
957 reference_callee_copied (CUMULATIVE_ARGS
*ca
, const function_arg_info
&arg
)
959 if (arg
.type
&& TREE_ADDRESSABLE (arg
.type
))
961 return targetm
.calls
.callee_copies (pack_cumulative_args (ca
), arg
);
965 /* Precompute all register parameters as described by ARGS, storing values
966 into fields within the ARGS array.
968 NUM_ACTUALS indicates the total number elements in the ARGS array.
970 Set REG_PARM_SEEN if we encounter a register parameter. */
973 precompute_register_parameters (int num_actuals
, struct arg_data
*args
,
980 for (i
= 0; i
< num_actuals
; i
++)
981 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
985 if (args
[i
].value
== 0)
988 args
[i
].value
= expand_normal (args
[i
].tree_value
);
989 preserve_temp_slots (args
[i
].value
);
993 /* If we are to promote the function arg to a wider mode,
996 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
998 = convert_modes (args
[i
].mode
,
999 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
1000 args
[i
].value
, args
[i
].unsignedp
);
1002 /* If the value is a non-legitimate constant, force it into a
1003 pseudo now. TLS symbols sometimes need a call to resolve. */
1004 if (CONSTANT_P (args
[i
].value
)
1005 && (!targetm
.legitimate_constant_p (args
[i
].mode
, args
[i
].value
)
1006 || targetm
.precompute_tls_p (args
[i
].mode
, args
[i
].value
)))
1007 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
1009 /* If we're going to have to load the value by parts, pull the
1010 parts into pseudos. The part extraction process can involve
1011 non-trivial computation. */
1012 if (GET_CODE (args
[i
].reg
) == PARALLEL
)
1014 tree type
= TREE_TYPE (args
[i
].tree_value
);
1015 args
[i
].parallel_value
1016 = emit_group_load_into_temps (args
[i
].reg
, args
[i
].value
,
1017 type
, int_size_in_bytes (type
));
1020 /* If the value is expensive, and we are inside an appropriately
1021 short loop, put the value into a pseudo and then put the pseudo
1024 For small register classes, also do this if this call uses
1025 register parameters. This is to avoid reload conflicts while
1026 loading the parameters registers. */
1028 else if ((! (REG_P (args
[i
].value
)
1029 || (GET_CODE (args
[i
].value
) == SUBREG
1030 && REG_P (SUBREG_REG (args
[i
].value
)))))
1031 && args
[i
].mode
!= BLKmode
1032 && (set_src_cost (args
[i
].value
, args
[i
].mode
,
1033 optimize_insn_for_speed_p ())
1034 > COSTS_N_INSNS (1))
1036 && targetm
.small_register_classes_for_mode_p (args
[i
].mode
))
1038 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
1042 #ifdef REG_PARM_STACK_SPACE
1044 /* The argument list is the property of the called routine and it
1045 may clobber it. If the fixed area has been used for previous
1046 parameters, we must save and restore it. */
1049 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
1054 /* Compute the boundary of the area that needs to be saved, if any. */
1055 high
= reg_parm_stack_space
;
1056 if (ARGS_GROW_DOWNWARD
)
1059 if (high
> highest_outgoing_arg_in_use
)
1060 high
= highest_outgoing_arg_in_use
;
1062 for (low
= 0; low
< high
; low
++)
1063 if (stack_usage_map
[low
] != 0 || low
>= stack_usage_watermark
)
1066 machine_mode save_mode
;
1072 while (stack_usage_map
[--high
] == 0)
1076 *high_to_save
= high
;
1078 num_to_save
= high
- low
+ 1;
1080 /* If we don't have the required alignment, must do this
1082 scalar_int_mode imode
;
1083 if (int_mode_for_size (num_to_save
* BITS_PER_UNIT
, 1).exists (&imode
)
1084 && (low
& (MIN (GET_MODE_SIZE (imode
),
1085 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)) == 0)
1088 save_mode
= BLKmode
;
1090 if (ARGS_GROW_DOWNWARD
)
1095 addr
= plus_constant (Pmode
, argblock
, delta
);
1096 stack_area
= gen_rtx_MEM (save_mode
, memory_address (save_mode
, addr
));
1098 set_mem_align (stack_area
, PARM_BOUNDARY
);
1099 if (save_mode
== BLKmode
)
1101 save_area
= assign_stack_temp (BLKmode
, num_to_save
);
1102 emit_block_move (validize_mem (save_area
), stack_area
,
1103 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
1107 save_area
= gen_reg_rtx (save_mode
);
1108 emit_move_insn (save_area
, stack_area
);
1118 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
1120 machine_mode save_mode
= GET_MODE (save_area
);
1122 rtx addr
, stack_area
;
1124 if (ARGS_GROW_DOWNWARD
)
1125 delta
= -high_to_save
;
1127 delta
= low_to_save
;
1129 addr
= plus_constant (Pmode
, argblock
, delta
);
1130 stack_area
= gen_rtx_MEM (save_mode
, memory_address (save_mode
, addr
));
1131 set_mem_align (stack_area
, PARM_BOUNDARY
);
1133 if (save_mode
!= BLKmode
)
1134 emit_move_insn (stack_area
, save_area
);
1136 emit_block_move (stack_area
, validize_mem (save_area
),
1137 GEN_INT (high_to_save
- low_to_save
+ 1),
1138 BLOCK_OP_CALL_PARM
);
1140 #endif /* REG_PARM_STACK_SPACE */
1142 /* If any elements in ARGS refer to parameters that are to be passed in
1143 registers, but not in memory, and whose alignment does not permit a
1144 direct copy into registers. Copy the values into a group of pseudos
1145 which we will later copy into the appropriate hard registers.
1147 Pseudos for each unaligned argument will be stored into the array
1148 args[argnum].aligned_regs. The caller is responsible for deallocating
1149 the aligned_regs array if it is nonzero. */
1152 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
1156 for (i
= 0; i
< num_actuals
; i
++)
1157 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
1158 && GET_CODE (args
[i
].reg
) != PARALLEL
1159 && args
[i
].mode
== BLKmode
1160 && MEM_P (args
[i
].value
)
1161 && (MEM_ALIGN (args
[i
].value
)
1162 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
1164 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1165 int endian_correction
= 0;
1167 if (args
[i
].partial
)
1169 gcc_assert (args
[i
].partial
% UNITS_PER_WORD
== 0);
1170 args
[i
].n_aligned_regs
= args
[i
].partial
/ UNITS_PER_WORD
;
1174 args
[i
].n_aligned_regs
1175 = (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
1178 args
[i
].aligned_regs
= XNEWVEC (rtx
, args
[i
].n_aligned_regs
);
1180 /* Structures smaller than a word are normally aligned to the
1181 least significant byte. On a BYTES_BIG_ENDIAN machine,
1182 this means we must skip the empty high order bytes when
1183 calculating the bit offset. */
1184 if (bytes
< UNITS_PER_WORD
1185 #ifdef BLOCK_REG_PADDING
1186 && (BLOCK_REG_PADDING (args
[i
].mode
,
1187 TREE_TYPE (args
[i
].tree_value
), 1)
1193 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
1195 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1197 rtx reg
= gen_reg_rtx (word_mode
);
1198 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
1199 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
1201 args
[i
].aligned_regs
[j
] = reg
;
1202 word
= extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
1203 word_mode
, word_mode
, false, NULL
);
1205 /* There is no need to restrict this code to loading items
1206 in TYPE_ALIGN sized hunks. The bitfield instructions can
1207 load up entire word sized registers efficiently.
1209 ??? This may not be needed anymore.
1210 We use to emit a clobber here but that doesn't let later
1211 passes optimize the instructions we emit. By storing 0 into
1212 the register later passes know the first AND to zero out the
1213 bitfield being set in the register is unnecessary. The store
1214 of 0 will be deleted as will at least the first AND. */
1216 emit_move_insn (reg
, const0_rtx
);
1218 bytes
-= bitsize
/ BITS_PER_UNIT
;
1219 store_bit_field (reg
, bitsize
, endian_correction
, 0, 0,
1220 word_mode
, word
, false);
1225 /* The limit set by -Walloc-larger-than=. */
1226 static GTY(()) tree alloc_object_size_limit
;
1228 /* Initialize ALLOC_OBJECT_SIZE_LIMIT based on the -Walloc-size-larger-than=
1229 setting if the option is specified, or to the maximum object size if it
1230 is not. Return the initialized value. */
1233 alloc_max_size (void)
1235 if (alloc_object_size_limit
)
1236 return alloc_object_size_limit
;
1238 HOST_WIDE_INT limit
= warn_alloc_size_limit
;
1239 if (limit
== HOST_WIDE_INT_MAX
)
1240 limit
= tree_to_shwi (TYPE_MAX_VALUE (ptrdiff_type_node
));
1242 alloc_object_size_limit
= build_int_cst (size_type_node
, limit
);
1244 return alloc_object_size_limit
;
1247 /* Return true when EXP's range can be determined and set RANGE[] to it
1248 after adjusting it if necessary to make EXP a represents a valid size
1249 of object, or a valid size argument to an allocation function declared
1250 with attribute alloc_size (whose argument may be signed), or to a string
1251 manipulation function like memset.
1252 When ALLOW_ZERO is set in FLAGS, allow returning a range of [0, 0] for
1253 a size in an anti-range [1, N] where N > PTRDIFF_MAX. A zero range is
1254 a (nearly) invalid argument to allocation functions like malloc but it
1255 is a valid argument to functions like memset.
1256 When USE_LARGEST is set in FLAGS set RANGE to the largest valid subrange
1257 in a multi-range, otherwise to the smallest valid subrange. */
1260 get_size_range (range_query
*query
, tree exp
, gimple
*stmt
, tree range
[2],
1261 int flags
/* = 0 */)
1266 if (tree_fits_uhwi_p (exp
))
1268 /* EXP is a constant. */
1269 range
[0] = range
[1] = exp
;
1273 tree exptype
= TREE_TYPE (exp
);
1274 bool integral
= INTEGRAL_TYPE_P (exptype
);
1277 enum value_range_kind range_type
;
1280 query
= get_global_range_query ();
1286 query
->range_of_expr (vr
, exp
, stmt
);
1288 if (vr
.undefined_p ())
1289 vr
.set_varying (TREE_TYPE (exp
));
1290 range_type
= vr
.kind ();
1291 min
= wi::to_wide (vr
.min ());
1292 max
= wi::to_wide (vr
.max ());
1295 range_type
= VR_VARYING
;
1297 if (range_type
== VR_VARYING
)
1301 /* Use the full range of the type of the expression when
1302 no value range information is available. */
1303 range
[0] = TYPE_MIN_VALUE (exptype
);
1304 range
[1] = TYPE_MAX_VALUE (exptype
);
1308 range
[0] = NULL_TREE
;
1309 range
[1] = NULL_TREE
;
1313 unsigned expprec
= TYPE_PRECISION (exptype
);
1315 bool signed_p
= !TYPE_UNSIGNED (exptype
);
1317 if (range_type
== VR_ANTI_RANGE
)
1321 if (wi::les_p (max
, 0))
1323 /* EXP is not in a strictly negative range. That means
1324 it must be in some (not necessarily strictly) positive
1325 range which includes zero. Since in signed to unsigned
1326 conversions negative values end up converted to large
1327 positive values, and otherwise they are not valid sizes,
1328 the resulting range is in both cases [0, TYPE_MAX]. */
1329 min
= wi::zero (expprec
);
1330 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1332 else if (wi::les_p (min
- 1, 0))
1334 /* EXP is not in a negative-positive range. That means EXP
1335 is either negative, or greater than max. Since negative
1336 sizes are invalid make the range [MAX + 1, TYPE_MAX]. */
1338 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1343 min
= wi::zero (expprec
);
1348 wide_int maxsize
= wi::to_wide (max_object_size ());
1349 min
= wide_int::from (min
, maxsize
.get_precision (), UNSIGNED
);
1350 max
= wide_int::from (max
, maxsize
.get_precision (), UNSIGNED
);
1351 if (wi::eq_p (0, min
- 1))
1353 /* EXP is unsigned and not in the range [1, MAX]. That means
1354 it's either zero or greater than MAX. Even though 0 would
1355 normally be detected by -Walloc-zero, unless ALLOW_ZERO
1356 is set, set the range to [MAX, TYPE_MAX] so that when MAX
1357 is greater than the limit the whole range is diagnosed. */
1358 wide_int maxsize
= wi::to_wide (max_object_size ());
1359 if (flags
& SR_ALLOW_ZERO
)
1361 if (wi::leu_p (maxsize
, max
+ 1)
1362 || !(flags
& SR_USE_LARGEST
))
1363 min
= max
= wi::zero (expprec
);
1367 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1373 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1376 else if ((flags
& SR_USE_LARGEST
)
1377 && wi::ltu_p (max
+ 1, maxsize
))
1379 /* When USE_LARGEST is set and the larger of the two subranges
1380 is a valid size, use it... */
1386 /* ...otherwise use the smaller subrange. */
1388 min
= wi::zero (expprec
);
1393 range
[0] = wide_int_to_tree (exptype
, min
);
1394 range
[1] = wide_int_to_tree (exptype
, max
);
1400 get_size_range (tree exp
, tree range
[2], int flags
/* = 0 */)
1402 return get_size_range (/*query=*/NULL
, exp
, /*stmt=*/NULL
, range
, flags
);
1405 /* Diagnose a call EXP to function FN decorated with attribute alloc_size
1406 whose argument numbers given by IDX with values given by ARGS exceed
1407 the maximum object size or cause an unsigned oveflow (wrapping) when
1408 multiplied. FN is null when EXP is a call via a function pointer.
1409 When ARGS[0] is null the function does nothing. ARGS[1] may be null
1410 for functions like malloc, and non-null for those like calloc that
1411 are decorated with a two-argument attribute alloc_size. */
1414 maybe_warn_alloc_args_overflow (tree fn
, tree exp
, tree args
[2], int idx
[2])
1416 /* The range each of the (up to) two arguments is known to be in. */
1417 tree argrange
[2][2] = { { NULL_TREE
, NULL_TREE
}, { NULL_TREE
, NULL_TREE
} };
1419 /* Maximum object size set by -Walloc-size-larger-than= or SIZE_MAX / 2. */
1420 tree maxobjsize
= alloc_max_size ();
1422 location_t loc
= EXPR_LOCATION (exp
);
1424 tree fntype
= fn
? TREE_TYPE (fn
) : TREE_TYPE (TREE_TYPE (exp
));
1425 bool warned
= false;
1427 /* Validate each argument individually. */
1428 for (unsigned i
= 0; i
!= 2 && args
[i
]; ++i
)
1430 if (TREE_CODE (args
[i
]) == INTEGER_CST
)
1432 argrange
[i
][0] = args
[i
];
1433 argrange
[i
][1] = args
[i
];
1435 if (tree_int_cst_lt (args
[i
], integer_zero_node
))
1437 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1438 "argument %i value %qE is negative",
1439 idx
[i
] + 1, args
[i
]);
1441 else if (integer_zerop (args
[i
]))
1443 /* Avoid issuing -Walloc-zero for allocation functions other
1444 than __builtin_alloca that are declared with attribute
1445 returns_nonnull because there's no portability risk. This
1446 avoids warning for such calls to libiberty's xmalloc and
1448 Also avoid issuing the warning for calls to function named
1450 if (fn
&& fndecl_built_in_p (fn
, BUILT_IN_ALLOCA
)
1451 ? IDENTIFIER_LENGTH (DECL_NAME (fn
)) != 6
1452 : !lookup_attribute ("returns_nonnull",
1453 TYPE_ATTRIBUTES (fntype
)))
1454 warned
= warning_at (loc
, OPT_Walloc_zero
,
1455 "argument %i value is zero",
1458 else if (tree_int_cst_lt (maxobjsize
, args
[i
]))
1460 /* G++ emits calls to ::operator new[](SIZE_MAX) in C++98
1461 mode and with -fno-exceptions as a way to indicate array
1462 size overflow. There's no good way to detect C++98 here
1463 so avoid diagnosing these calls for all C++ modes. */
1468 && DECL_IS_OPERATOR_NEW_P (fn
)
1469 && integer_all_onesp (args
[i
]))
1472 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1473 "argument %i value %qE exceeds "
1474 "maximum object size %E",
1475 idx
[i
] + 1, args
[i
], maxobjsize
);
1478 else if (TREE_CODE (args
[i
]) == SSA_NAME
1479 && get_size_range (args
[i
], argrange
[i
]))
1481 /* Verify that the argument's range is not negative (including
1482 upper bound of zero). */
1483 if (tree_int_cst_lt (argrange
[i
][0], integer_zero_node
)
1484 && tree_int_cst_le (argrange
[i
][1], integer_zero_node
))
1486 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1487 "argument %i range [%E, %E] is negative",
1489 argrange
[i
][0], argrange
[i
][1]);
1491 else if (tree_int_cst_lt (maxobjsize
, argrange
[i
][0]))
1493 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1494 "argument %i range [%E, %E] exceeds "
1495 "maximum object size %E",
1497 argrange
[i
][0], argrange
[i
][1],
1506 /* For a two-argument alloc_size, validate the product of the two
1507 arguments if both of their values or ranges are known. */
1508 if (!warned
&& tree_fits_uhwi_p (argrange
[0][0])
1509 && argrange
[1][0] && tree_fits_uhwi_p (argrange
[1][0])
1510 && !integer_onep (argrange
[0][0])
1511 && !integer_onep (argrange
[1][0]))
1513 /* Check for overflow in the product of a function decorated with
1514 attribute alloc_size (X, Y). */
1515 unsigned szprec
= TYPE_PRECISION (size_type_node
);
1516 wide_int x
= wi::to_wide (argrange
[0][0], szprec
);
1517 wide_int y
= wi::to_wide (argrange
[1][0], szprec
);
1519 wi::overflow_type vflow
;
1520 wide_int prod
= wi::umul (x
, y
, &vflow
);
1523 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1524 "product %<%E * %E%> of arguments %i and %i "
1525 "exceeds %<SIZE_MAX%>",
1526 argrange
[0][0], argrange
[1][0],
1527 idx
[0] + 1, idx
[1] + 1);
1528 else if (wi::ltu_p (wi::to_wide (maxobjsize
, szprec
), prod
))
1529 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1530 "product %<%E * %E%> of arguments %i and %i "
1531 "exceeds maximum object size %E",
1532 argrange
[0][0], argrange
[1][0],
1533 idx
[0] + 1, idx
[1] + 1,
1538 /* Print the full range of each of the two arguments to make
1539 it clear when it is, in fact, in a range and not constant. */
1540 if (argrange
[0][0] != argrange
[0][1])
1541 inform (loc
, "argument %i in the range [%E, %E]",
1542 idx
[0] + 1, argrange
[0][0], argrange
[0][1]);
1543 if (argrange
[1][0] != argrange
[1][1])
1544 inform (loc
, "argument %i in the range [%E, %E]",
1545 idx
[1] + 1, argrange
[1][0], argrange
[1][1]);
1551 location_t fnloc
= DECL_SOURCE_LOCATION (fn
);
1553 if (DECL_IS_UNDECLARED_BUILTIN (fn
))
1555 "in a call to built-in allocation function %qD", fn
);
1558 "in a call to allocation function %qD declared here", fn
);
1562 /* If EXPR refers to a character array or pointer declared attribute
1563 nonstring return a decl for that array or pointer and set *REF to
1564 the referenced enclosing object or pointer. Otherwise returns
1568 get_attr_nonstring_decl (tree expr
, tree
*ref
)
1571 tree var
= NULL_TREE
;
1572 if (TREE_CODE (decl
) == SSA_NAME
)
1574 gimple
*def
= SSA_NAME_DEF_STMT (decl
);
1576 if (is_gimple_assign (def
))
1578 tree_code code
= gimple_assign_rhs_code (def
);
1579 if (code
== ADDR_EXPR
1580 || code
== COMPONENT_REF
1581 || code
== VAR_DECL
)
1582 decl
= gimple_assign_rhs1 (def
);
1585 var
= SSA_NAME_VAR (decl
);
1588 if (TREE_CODE (decl
) == ADDR_EXPR
)
1589 decl
= TREE_OPERAND (decl
, 0);
1591 /* To simplify calling code, store the referenced DECL regardless of
1592 the attribute determined below, but avoid storing the SSA_NAME_VAR
1593 obtained above (it's not useful for dataflow purposes). */
1597 /* Use the SSA_NAME_VAR that was determined above to see if it's
1598 declared nonstring. Otherwise drill down into the referenced
1602 else if (TREE_CODE (decl
) == ARRAY_REF
)
1603 decl
= TREE_OPERAND (decl
, 0);
1604 else if (TREE_CODE (decl
) == COMPONENT_REF
)
1605 decl
= TREE_OPERAND (decl
, 1);
1606 else if (TREE_CODE (decl
) == MEM_REF
)
1607 return get_attr_nonstring_decl (TREE_OPERAND (decl
, 0), ref
);
1610 && lookup_attribute ("nonstring", DECL_ATTRIBUTES (decl
)))
1616 /* Warn about passing a non-string array/pointer to a built-in function
1617 that expects a nul-terminated string argument. Returns true if
1618 a warning has been issued.*/
1621 maybe_warn_nonstring_arg (tree fndecl
, tree exp
)
1623 if (!fndecl
|| !fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
1626 if (!warn_stringop_overread
|| warning_suppressed_p (exp
, OPT_Wstringop_overread
))
1629 /* Avoid clearly invalid calls (more checking done below). */
1630 unsigned nargs
= call_expr_nargs (exp
);
1634 /* The bound argument to a bounded string function like strncpy. */
1635 tree bound
= NULL_TREE
;
1637 /* The longest known or possible string argument to one of the comparison
1638 functions. If the length is less than the bound it is used instead.
1639 Since the length is only used for warning and not for code generation
1640 disable strict mode in the calls to get_range_strlen below. */
1641 tree maxlen
= NULL_TREE
;
1643 /* It's safe to call "bounded" string functions with a non-string
1644 argument since the functions provide an explicit bound for this
1645 purpose. The exception is strncat where the bound may refer to
1646 either the destination or the source. */
1647 int fncode
= DECL_FUNCTION_CODE (fndecl
);
1650 case BUILT_IN_STRCMP
:
1651 case BUILT_IN_STRNCMP
:
1652 case BUILT_IN_STRNCASECMP
:
1654 /* For these, if one argument refers to one or more of a set
1655 of string constants or arrays of known size, determine
1656 the range of their known or possible lengths and use it
1657 conservatively as the bound for the unbounded function,
1658 and to adjust the range of the bound of the bounded ones. */
1659 for (unsigned argno
= 0;
1660 argno
< MIN (nargs
, 2)
1661 && !(maxlen
&& TREE_CODE (maxlen
) == INTEGER_CST
); argno
++)
1663 tree arg
= CALL_EXPR_ARG (exp
, argno
);
1664 if (!get_attr_nonstring_decl (arg
))
1666 c_strlen_data lendata
= { };
1667 /* Set MAXBOUND to an arbitrary non-null non-integer
1668 node as a request to have it set to the length of
1669 the longest string in a PHI. */
1670 lendata
.maxbound
= arg
;
1671 get_range_strlen (arg
, &lendata
, /* eltsize = */ 1);
1672 maxlen
= lendata
.maxbound
;
1678 case BUILT_IN_STRNCAT
:
1679 case BUILT_IN_STPNCPY
:
1680 case BUILT_IN_STRNCPY
:
1682 bound
= CALL_EXPR_ARG (exp
, 2);
1685 case BUILT_IN_STRNDUP
:
1687 bound
= CALL_EXPR_ARG (exp
, 1);
1690 case BUILT_IN_STRNLEN
:
1692 tree arg
= CALL_EXPR_ARG (exp
, 0);
1693 if (!get_attr_nonstring_decl (arg
))
1695 c_strlen_data lendata
= { };
1696 /* Set MAXBOUND to an arbitrary non-null non-integer
1697 node as a request to have it set to the length of
1698 the longest string in a PHI. */
1699 lendata
.maxbound
= arg
;
1700 get_range_strlen (arg
, &lendata
, /* eltsize = */ 1);
1701 maxlen
= lendata
.maxbound
;
1704 bound
= CALL_EXPR_ARG (exp
, 1);
1712 /* Determine the range of the bound argument (if specified). */
1713 tree bndrng
[2] = { NULL_TREE
, NULL_TREE
};
1717 get_size_range (bound
, bndrng
);
1720 location_t loc
= EXPR_LOCATION (exp
);
1724 /* Diagnose excessive bound prior to the adjustment below and
1725 regardless of attribute nonstring. */
1726 tree maxobjsize
= max_object_size ();
1727 if (tree_int_cst_lt (maxobjsize
, bndrng
[0]))
1729 bool warned
= false;
1730 if (tree_int_cst_equal (bndrng
[0], bndrng
[1]))
1731 warned
= warning_at (loc
, OPT_Wstringop_overread
,
1732 "%qD specified bound %E "
1733 "exceeds maximum object size %E",
1734 fndecl
, bndrng
[0], maxobjsize
);
1736 warned
= warning_at (loc
, OPT_Wstringop_overread
,
1737 "%qD specified bound [%E, %E] "
1738 "exceeds maximum object size %E",
1739 fndecl
, bndrng
[0], bndrng
[1],
1742 suppress_warning (exp
, OPT_Wstringop_overread
);
1748 if (maxlen
&& !integer_all_onesp (maxlen
))
1750 /* Add one for the nul. */
1751 maxlen
= const_binop (PLUS_EXPR
, TREE_TYPE (maxlen
), maxlen
,
1756 /* Conservatively use the upper bound of the lengths for
1757 both the lower and the upper bound of the operation. */
1760 bound
= void_type_node
;
1764 /* Replace the bound on the operation with the upper bound
1765 of the length of the string if the latter is smaller. */
1766 if (tree_int_cst_lt (maxlen
, bndrng
[0]))
1768 else if (tree_int_cst_lt (maxlen
, bndrng
[1]))
1773 bool any_arg_warned
= false;
1774 /* Iterate over the built-in function's formal arguments and check
1775 each const char* against the actual argument. If the actual
1776 argument is declared attribute non-string issue a warning unless
1777 the argument's maximum length is bounded. */
1778 function_args_iterator it
;
1779 function_args_iter_init (&it
, TREE_TYPE (fndecl
));
1781 for (unsigned argno
= 0; ; ++argno
, function_args_iter_next (&it
))
1783 /* Avoid iterating past the declared argument in a call
1784 to function declared without a prototype. */
1788 tree argtype
= function_args_iter_cond (&it
);
1792 if (TREE_CODE (argtype
) != POINTER_TYPE
)
1795 argtype
= TREE_TYPE (argtype
);
1797 if (TREE_CODE (argtype
) != INTEGER_TYPE
1798 || !TYPE_READONLY (argtype
))
1801 argtype
= TYPE_MAIN_VARIANT (argtype
);
1802 if (argtype
!= char_type_node
)
1805 tree callarg
= CALL_EXPR_ARG (exp
, argno
);
1806 if (TREE_CODE (callarg
) == ADDR_EXPR
)
1807 callarg
= TREE_OPERAND (callarg
, 0);
1809 /* See if the destination is declared with attribute "nonstring". */
1810 tree decl
= get_attr_nonstring_decl (callarg
);
1814 /* The maximum number of array elements accessed. */
1815 offset_int wibnd
= 0;
1817 if (argno
&& fncode
== BUILT_IN_STRNCAT
)
1819 /* See if the bound in strncat is derived from the length
1820 of the strlen of the destination (as it's expected to be).
1821 If so, reset BOUND and FNCODE to trigger a warning. */
1822 tree dstarg
= CALL_EXPR_ARG (exp
, 0);
1823 if (is_strlen_related_p (dstarg
, bound
))
1825 /* The bound applies to the destination, not to the source,
1826 so reset these to trigger a warning without mentioning
1832 /* Use the upper bound of the range for strncat. */
1833 wibnd
= wi::to_offset (bndrng
[1]);
1836 /* Use the lower bound of the range for functions other than
1838 wibnd
= wi::to_offset (bndrng
[0]);
1840 /* Determine the size of the argument array if it is one. */
1841 offset_int asize
= wibnd
;
1842 bool known_size
= false;
1843 tree type
= TREE_TYPE (decl
);
1845 /* Determine the array size. For arrays of unknown bound and
1846 pointers reset BOUND to trigger the appropriate warning. */
1847 if (TREE_CODE (type
) == ARRAY_TYPE
)
1849 if (tree arrbnd
= TYPE_DOMAIN (type
))
1851 if ((arrbnd
= TYPE_MAX_VALUE (arrbnd
)))
1853 asize
= wi::to_offset (arrbnd
) + 1;
1857 else if (bound
== void_type_node
)
1860 else if (bound
== void_type_node
)
1863 /* In a call to strncat with a bound in a range whose lower but
1864 not upper bound is less than the array size, reset ASIZE to
1865 be the same as the bound and the other variable to trigger
1866 the apprpriate warning below. */
1867 if (fncode
== BUILT_IN_STRNCAT
1868 && bndrng
[0] != bndrng
[1]
1869 && wi::ltu_p (wi::to_offset (bndrng
[0]), asize
)
1871 || wi::ltu_p (asize
, wibnd
)))
1878 bool warned
= false;
1880 auto_diagnostic_group d
;
1881 if (wi::ltu_p (asize
, wibnd
))
1883 if (bndrng
[0] == bndrng
[1])
1884 warned
= warning_at (loc
, OPT_Wstringop_overread
,
1885 "%qD argument %i declared attribute "
1886 "%<nonstring%> is smaller than the specified "
1888 fndecl
, argno
+ 1, wibnd
.to_uhwi ());
1889 else if (wi::ltu_p (asize
, wi::to_offset (bndrng
[0])))
1890 warned
= warning_at (loc
, OPT_Wstringop_overread
,
1891 "%qD argument %i declared attribute "
1892 "%<nonstring%> is smaller than "
1893 "the specified bound [%E, %E]",
1894 fndecl
, argno
+ 1, bndrng
[0], bndrng
[1]);
1896 warned
= warning_at (loc
, OPT_Wstringop_overread
,
1897 "%qD argument %i declared attribute "
1898 "%<nonstring%> may be smaller than "
1899 "the specified bound [%E, %E]",
1900 fndecl
, argno
+ 1, bndrng
[0], bndrng
[1]);
1902 else if (fncode
== BUILT_IN_STRNCAT
)
1903 ; /* Avoid warning for calls to strncat() when the bound
1904 is equal to the size of the non-string argument. */
1906 warned
= warning_at (loc
, OPT_Wstringop_overread
,
1907 "%qD argument %i declared attribute %<nonstring%>",
1912 inform (DECL_SOURCE_LOCATION (decl
),
1913 "argument %qD declared here", decl
);
1914 any_arg_warned
= true;
1919 suppress_warning (exp
, OPT_Wstringop_overread
);
1921 return any_arg_warned
;
1924 /* Issue an error if CALL_EXPR was flagged as requiring
1925 tall-call optimization. */
1928 maybe_complain_about_tail_call (tree call_expr
, const char *reason
)
1930 gcc_assert (TREE_CODE (call_expr
) == CALL_EXPR
);
1931 if (!CALL_EXPR_MUST_TAIL_CALL (call_expr
))
1934 error_at (EXPR_LOCATION (call_expr
), "cannot tail-call: %s", reason
);
1937 /* Returns the type of the argument ARGNO to function with type FNTYPE
1938 or null when the typoe cannot be determined or no such argument exists. */
1941 fntype_argno_type (tree fntype
, unsigned argno
)
1943 if (!prototype_p (fntype
))
1947 function_args_iterator it
;
1948 FOREACH_FUNCTION_ARGS (fntype
, argtype
, it
)
1955 /* Helper to append the "human readable" attribute access specification
1956 described by ACCESS to the array ATTRSTR with size STRSIZE. Used in
1960 append_attrname (const std::pair
<int, attr_access
> &access
,
1961 char *attrstr
, size_t strsize
)
1963 if (access
.second
.internal_p
)
1966 tree str
= access
.second
.to_external_string ();
1967 gcc_assert (strsize
>= (size_t) TREE_STRING_LENGTH (str
));
1968 strcpy (attrstr
, TREE_STRING_POINTER (str
));
1971 /* Iterate over attribute access read-only, read-write, and write-only
1972 arguments and diagnose past-the-end accesses and related problems
1973 in the function call EXP. */
1976 maybe_warn_rdwr_sizes (rdwr_map
*rwm
, tree fndecl
, tree fntype
, tree exp
)
1978 auto_diagnostic_group adg
;
1980 /* Set if a warning has been issued for any argument (used to decide
1981 whether to emit an informational note at the end). */
1982 opt_code opt_warned
= N_OPTS
;
1984 /* A string describing the attributes that the warnings issued by this
1985 function apply to. Used to print one informational note per function
1986 call, rather than one per warning. That reduces clutter. */
1990 for (rdwr_map::iterator it
= rwm
->begin (); it
!= rwm
->end (); ++it
)
1992 std::pair
<int, attr_access
> access
= *it
;
1994 /* Get the function call arguments corresponding to the attribute's
1995 positional arguments. When both arguments have been specified
1996 there will be two entries in *RWM, one for each. They are
1997 cross-referenced by their respective argument numbers in
1998 ACCESS.PTRARG and ACCESS.SIZARG. */
1999 const int ptridx
= access
.second
.ptrarg
;
2000 const int sizidx
= access
.second
.sizarg
;
2002 gcc_assert (ptridx
!= -1);
2003 gcc_assert (access
.first
== ptridx
|| access
.first
== sizidx
);
2005 /* The pointer is set to null for the entry corresponding to
2006 the size argument. Skip it. It's handled when the entry
2007 corresponding to the pointer argument comes up. */
2008 if (!access
.second
.ptr
)
2011 tree ptrtype
= fntype_argno_type (fntype
, ptridx
);
2012 tree argtype
= TREE_TYPE (ptrtype
);
2014 /* The size of the access by the call. */
2018 /* If only the pointer attribute operand was specified and
2019 not size, set SIZE to the greater of MINSIZE or size of
2020 one element of the pointed to type to detect smaller
2021 objects (null pointers are diagnosed in this case only
2022 if the pointer is also declared with attribute nonnull. */
2023 if (access
.second
.minsize
2024 && access
.second
.minsize
!= HOST_WIDE_INT_M1U
)
2025 access_size
= build_int_cstu (sizetype
, access
.second
.minsize
);
2027 access_size
= size_one_node
;
2030 access_size
= rwm
->get (sizidx
)->size
;
2032 /* Format the value or range to avoid an explosion of messages. */
2034 tree sizrng
[2] = { size_zero_node
, build_all_ones_cst (sizetype
) };
2035 if (get_size_range (access_size
, sizrng
, true))
2037 char *s0
= print_generic_expr_to_str (sizrng
[0]);
2038 if (tree_int_cst_equal (sizrng
[0], sizrng
[1]))
2040 gcc_checking_assert (strlen (s0
) < sizeof sizstr
);
2041 strcpy (sizstr
, s0
);
2045 char *s1
= print_generic_expr_to_str (sizrng
[1]);
2046 gcc_checking_assert (strlen (s0
) + strlen (s1
)
2047 < sizeof sizstr
- 4);
2048 sprintf (sizstr
, "[%s, %s]", s0
, s1
);
2056 /* Set if a warning has been issued for the current argument. */
2057 opt_code arg_warned
= no_warning
;
2058 location_t loc
= EXPR_LOCATION (exp
);
2059 tree ptr
= access
.second
.ptr
;
2061 && tree_int_cst_sgn (sizrng
[0]) < 0
2062 && tree_int_cst_sgn (sizrng
[1]) < 0)
2064 /* Warn about negative sizes. */
2065 if (access
.second
.internal_p
)
2067 const std::string argtypestr
2068 = access
.second
.array_as_string (ptrtype
);
2070 if (warning_at (loc
, OPT_Wstringop_overflow_
,
2071 "bound argument %i value %s is "
2072 "negative for a variable length array "
2073 "argument %i of type %s",
2075 ptridx
+ 1, argtypestr
.c_str ()))
2076 arg_warned
= OPT_Wstringop_overflow_
;
2078 else if (warning_at (loc
, OPT_Wstringop_overflow_
,
2079 "argument %i value %s is negative",
2080 sizidx
+ 1, sizstr
))
2081 arg_warned
= OPT_Wstringop_overflow_
;
2083 if (arg_warned
!= no_warning
)
2085 append_attrname (access
, attrstr
, sizeof attrstr
);
2086 /* Remember a warning has been issued and avoid warning
2087 again below for the same attribute. */
2088 opt_warned
= arg_warned
;
2093 if (tree_int_cst_sgn (sizrng
[0]) >= 0)
2095 if (COMPLETE_TYPE_P (argtype
))
2097 /* Multiply ACCESS_SIZE by the size of the type the pointer
2098 argument points to. If it's incomplete the size is used
2100 if (tree argsize
= TYPE_SIZE_UNIT (argtype
))
2101 if (TREE_CODE (argsize
) == INTEGER_CST
)
2103 const int prec
= TYPE_PRECISION (sizetype
);
2104 wide_int minsize
= wi::to_wide (sizrng
[0], prec
);
2105 minsize
*= wi::to_wide (argsize
, prec
);
2106 access_size
= wide_int_to_tree (sizetype
, minsize
);
2111 access_size
= NULL_TREE
;
2113 if (integer_zerop (ptr
))
2115 if (sizidx
>= 0 && tree_int_cst_sgn (sizrng
[0]) > 0)
2117 /* Warn about null pointers with positive sizes. This is
2118 different from also declaring the pointer argument with
2119 attribute nonnull when the function accepts null pointers
2120 only when the corresponding size is zero. */
2121 if (access
.second
.internal_p
)
2123 const std::string argtypestr
2124 = access
.second
.array_as_string (ptrtype
);
2126 if (warning_at (loc
, OPT_Wnonnull
,
2127 "argument %i of variable length "
2128 "array %s is null but "
2129 "the corresponding bound argument "
2131 sizidx
+ 1, argtypestr
.c_str (),
2132 ptridx
+ 1, sizstr
))
2133 arg_warned
= OPT_Wnonnull
;
2135 else if (warning_at (loc
, OPT_Wnonnull
,
2136 "argument %i is null but "
2137 "the corresponding size argument "
2139 ptridx
+ 1, sizidx
+ 1, sizstr
))
2140 arg_warned
= OPT_Wnonnull
;
2142 else if (access_size
&& access
.second
.static_p
)
2144 /* Warn about null pointers for [static N] array arguments
2145 but do not warn for ordinary (i.e., nonstatic) arrays. */
2146 if (warning_at (loc
, OPT_Wnonnull
,
2147 "argument %i to %<%T[static %E]%> "
2148 "is null where non-null expected",
2149 ptridx
+ 1, argtype
, access_size
))
2150 arg_warned
= OPT_Wnonnull
;
2153 if (arg_warned
!= no_warning
)
2155 append_attrname (access
, attrstr
, sizeof attrstr
);
2156 /* Remember a warning has been issued and avoid warning
2157 again below for the same attribute. */
2158 opt_warned
= OPT_Wnonnull
;
2163 access_data
data (ptr
, access
.second
.mode
, NULL_TREE
, false,
2165 access_ref
* const pobj
= (access
.second
.mode
== access_write_only
2166 ? &data
.dst
: &data
.src
);
2167 tree objsize
= compute_objsize (ptr
, 1, pobj
);
2169 /* The size of the destination or source object. */
2170 tree dstsize
= NULL_TREE
, srcsize
= NULL_TREE
;
2171 if (access
.second
.mode
== access_read_only
2172 || access
.second
.mode
== access_none
)
2174 /* For a read-only argument there is no destination. For
2175 no access, set the source as well and differentiate via
2176 the access flag below. */
2178 if (access
.second
.mode
== access_read_only
2179 || access
.second
.mode
== access_none
)
2181 /* For a read-only attribute there is no destination so
2182 clear OBJSIZE. This emits "reading N bytes" kind of
2183 diagnostics instead of the "writing N bytes" kind,
2184 unless MODE is none. */
2185 objsize
= NULL_TREE
;
2191 /* Clear the no-warning bit in case it was set by check_access
2192 in a prior iteration so that accesses via different arguments
2194 suppress_warning (exp
, OPT_Wstringop_overflow_
, false);
2195 access_mode mode
= data
.mode
;
2196 if (mode
== access_deferred
)
2197 mode
= TYPE_READONLY (argtype
) ? access_read_only
: access_read_write
;
2198 check_access (exp
, access_size
, /*maxread=*/ NULL_TREE
, srcsize
,
2199 dstsize
, mode
, &data
);
2201 if (warning_suppressed_p (exp
, OPT_Wstringop_overflow_
))
2202 opt_warned
= OPT_Wstringop_overflow_
;
2203 if (opt_warned
!= N_OPTS
)
2205 if (access
.second
.internal_p
)
2206 inform (loc
, "referencing argument %u of type %qT",
2207 ptridx
+ 1, ptrtype
);
2209 /* If check_access issued a warning above, append the relevant
2210 attribute to the string. */
2211 append_attrname (access
, attrstr
, sizeof attrstr
);
2218 inform (DECL_SOURCE_LOCATION (fndecl
),
2219 "in a call to function %qD declared with attribute %qs",
2222 inform (EXPR_LOCATION (fndecl
),
2223 "in a call with type %qT and attribute %qs",
2226 else if (opt_warned
!= N_OPTS
)
2229 inform (DECL_SOURCE_LOCATION (fndecl
),
2230 "in a call to function %qD", fndecl
);
2232 inform (EXPR_LOCATION (fndecl
),
2233 "in a call with type %qT", fntype
);
2236 /* Set the bit in case if was cleared and not set above. */
2237 if (opt_warned
!= N_OPTS
)
2238 suppress_warning (exp
, opt_warned
);
2241 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
2244 NUM_ACTUALS is the total number of parameters.
2246 N_NAMED_ARGS is the total number of named arguments.
2248 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
2251 FNDECL is the tree code for the target of this call (if known)
2253 ARGS_SO_FAR holds state needed by the target to know where to place
2256 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
2257 for arguments which are passed in registers.
2259 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
2260 and may be modified by this routine.
2262 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
2263 flags which may be modified by this routine.
2265 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
2266 that requires allocation of stack space.
2268 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
2269 the thunked-to function. */
2272 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
2273 struct arg_data
*args
,
2274 struct args_size
*args_size
,
2275 int n_named_args ATTRIBUTE_UNUSED
,
2276 tree exp
, tree struct_value_addr_value
,
2277 tree fndecl
, tree fntype
,
2278 cumulative_args_t args_so_far
,
2279 int reg_parm_stack_space
,
2280 rtx
*old_stack_level
,
2281 poly_int64_pod
*old_pending_adj
,
2282 int *must_preallocate
, int *ecf_flags
,
2283 bool *may_tailcall
, bool call_from_thunk_p
)
2285 CUMULATIVE_ARGS
*args_so_far_pnt
= get_cumulative_args (args_so_far
);
2286 location_t loc
= EXPR_LOCATION (exp
);
2288 /* Count arg position in order args appear. */
2293 args_size
->constant
= 0;
2296 bitmap_obstack_initialize (NULL
);
2298 /* In this loop, we consider args in the order they are written.
2299 We fill up ARGS from the back. */
2301 i
= num_actuals
- 1;
2304 call_expr_arg_iterator iter
;
2306 bitmap slots
= NULL
;
2308 if (struct_value_addr_value
)
2310 args
[j
].tree_value
= struct_value_addr_value
;
2314 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2316 tree argtype
= TREE_TYPE (arg
);
2318 if (targetm
.calls
.split_complex_arg
2320 && TREE_CODE (argtype
) == COMPLEX_TYPE
2321 && targetm
.calls
.split_complex_arg (argtype
))
2323 tree subtype
= TREE_TYPE (argtype
);
2324 args
[j
].tree_value
= build1 (REALPART_EXPR
, subtype
, arg
);
2326 args
[j
].tree_value
= build1 (IMAGPART_EXPR
, subtype
, arg
);
2329 args
[j
].tree_value
= arg
;
2335 BITMAP_FREE (slots
);
2338 bitmap_obstack_release (NULL
);
2340 tree fntypeattrs
= TYPE_ATTRIBUTES (fntype
);
2341 /* Extract attribute alloc_size from the type of the called expression
2342 (which could be a function or a function pointer) and if set, store
2343 the indices of the corresponding arguments in ALLOC_IDX, and then
2344 the actual argument(s) at those indices in ALLOC_ARGS. */
2345 int alloc_idx
[2] = { -1, -1 };
2346 if (tree alloc_size
= lookup_attribute ("alloc_size", fntypeattrs
))
2348 tree args
= TREE_VALUE (alloc_size
);
2349 alloc_idx
[0] = TREE_INT_CST_LOW (TREE_VALUE (args
)) - 1;
2350 if (TREE_CHAIN (args
))
2351 alloc_idx
[1] = TREE_INT_CST_LOW (TREE_VALUE (TREE_CHAIN (args
))) - 1;
2354 /* Array for up to the two attribute alloc_size arguments. */
2355 tree alloc_args
[] = { NULL_TREE
, NULL_TREE
};
2357 /* Map of attribute accewss specifications for function arguments. */
2359 init_attr_rdwr_indices (&rdwr_idx
, fntypeattrs
);
2361 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
2362 for (argpos
= 0; argpos
< num_actuals
; i
--, argpos
++)
2364 tree type
= TREE_TYPE (args
[i
].tree_value
);
2367 /* Replace erroneous argument with constant zero. */
2368 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
2369 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
2371 /* If TYPE is a transparent union or record, pass things the way
2372 we would pass the first field of the union or record. We have
2373 already verified that the modes are the same. */
2374 if (RECORD_OR_UNION_TYPE_P (type
) && TYPE_TRANSPARENT_AGGR (type
))
2375 type
= TREE_TYPE (first_field (type
));
2377 /* Decide where to pass this arg.
2379 args[i].reg is nonzero if all or part is passed in registers.
2381 args[i].partial is nonzero if part but not all is passed in registers,
2382 and the exact value says how many bytes are passed in registers.
2384 args[i].pass_on_stack is nonzero if the argument must at least be
2385 computed on the stack. It may then be loaded back into registers
2386 if args[i].reg is nonzero.
2388 These decisions are driven by the FUNCTION_... macros and must agree
2389 with those made by function.c. */
2391 /* See if this argument should be passed by invisible reference. */
2392 function_arg_info
arg (type
, argpos
< n_named_args
);
2393 if (pass_by_reference (args_so_far_pnt
, arg
))
2395 const bool callee_copies
2396 = reference_callee_copied (args_so_far_pnt
, arg
);
2399 /* If we're compiling a thunk, pass directly the address of an object
2400 already in memory, instead of making a copy. Likewise if we want
2401 to make the copy in the callee instead of the caller. */
2402 if ((call_from_thunk_p
|| callee_copies
)
2403 && TREE_CODE (args
[i
].tree_value
) != WITH_SIZE_EXPR
2404 && ((base
= get_base_address (args
[i
].tree_value
)), true)
2405 && TREE_CODE (base
) != SSA_NAME
2406 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
))))
2408 /* We may have turned the parameter value into an SSA name.
2409 Go back to the original parameter so we can take the
2411 if (TREE_CODE (args
[i
].tree_value
) == SSA_NAME
)
2413 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args
[i
].tree_value
));
2414 args
[i
].tree_value
= SSA_NAME_VAR (args
[i
].tree_value
);
2415 gcc_assert (TREE_CODE (args
[i
].tree_value
) == PARM_DECL
);
2417 /* Argument setup code may have copied the value to register. We
2418 revert that optimization now because the tail call code must
2419 use the original location. */
2420 if (TREE_CODE (args
[i
].tree_value
) == PARM_DECL
2421 && !MEM_P (DECL_RTL (args
[i
].tree_value
))
2422 && DECL_INCOMING_RTL (args
[i
].tree_value
)
2423 && MEM_P (DECL_INCOMING_RTL (args
[i
].tree_value
)))
2424 set_decl_rtl (args
[i
].tree_value
,
2425 DECL_INCOMING_RTL (args
[i
].tree_value
));
2427 mark_addressable (args
[i
].tree_value
);
2429 /* We can't use sibcalls if a callee-copied argument is
2430 stored in the current function's frame. */
2431 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
2433 *may_tailcall
= false;
2434 maybe_complain_about_tail_call (exp
,
2435 "a callee-copied argument is"
2436 " stored in the current"
2437 " function's frame");
2440 args
[i
].tree_value
= build_fold_addr_expr_loc (loc
,
2441 args
[i
].tree_value
);
2442 type
= TREE_TYPE (args
[i
].tree_value
);
2444 if (*ecf_flags
& ECF_CONST
)
2445 *ecf_flags
&= ~(ECF_CONST
| ECF_LOOPING_CONST_OR_PURE
);
2449 /* We make a copy of the object and pass the address to the
2450 function being called. */
2453 if (!COMPLETE_TYPE_P (type
)
2454 || TREE_CODE (TYPE_SIZE_UNIT (type
)) != INTEGER_CST
2455 || (flag_stack_check
== GENERIC_STACK_CHECK
2456 && compare_tree_int (TYPE_SIZE_UNIT (type
),
2457 STACK_CHECK_MAX_VAR_SIZE
) > 0))
2459 /* This is a variable-sized object. Make space on the stack
2461 rtx size_rtx
= expr_size (args
[i
].tree_value
);
2463 if (*old_stack_level
== 0)
2465 emit_stack_save (SAVE_BLOCK
, old_stack_level
);
2466 *old_pending_adj
= pending_stack_adjust
;
2467 pending_stack_adjust
= 0;
2470 /* We can pass TRUE as the 4th argument because we just
2471 saved the stack pointer and will restore it right after
2473 copy
= allocate_dynamic_stack_space (size_rtx
,
2476 max_int_size_in_bytes
2479 copy
= gen_rtx_MEM (BLKmode
, copy
);
2480 set_mem_attributes (copy
, type
, 1);
2483 copy
= assign_temp (type
, 1, 0);
2485 store_expr (args
[i
].tree_value
, copy
, 0, false, false);
2487 /* Just change the const function to pure and then let
2488 the next test clear the pure based on
2490 if (*ecf_flags
& ECF_CONST
)
2492 *ecf_flags
&= ~ECF_CONST
;
2493 *ecf_flags
|= ECF_PURE
;
2496 if (!callee_copies
&& *ecf_flags
& ECF_PURE
)
2497 *ecf_flags
&= ~(ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
2500 = build_fold_addr_expr_loc (loc
, make_tree (type
, copy
));
2501 type
= TREE_TYPE (args
[i
].tree_value
);
2502 *may_tailcall
= false;
2503 maybe_complain_about_tail_call (exp
,
2504 "argument must be passed"
2507 arg
.pass_by_reference
= true;
2510 unsignedp
= TYPE_UNSIGNED (type
);
2513 = promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
2514 fndecl
? TREE_TYPE (fndecl
) : fntype
, 0);
2516 args
[i
].unsignedp
= unsignedp
;
2517 args
[i
].mode
= arg
.mode
;
2519 targetm
.calls
.warn_parameter_passing_abi (args_so_far
, type
);
2521 args
[i
].reg
= targetm
.calls
.function_arg (args_so_far
, arg
);
2523 if (args
[i
].reg
&& CONST_INT_P (args
[i
].reg
))
2526 /* If this is a sibling call and the machine has register windows, the
2527 register window has to be unwinded before calling the routine, so
2528 arguments have to go into the incoming registers. */
2529 if (targetm
.calls
.function_incoming_arg
!= targetm
.calls
.function_arg
)
2530 args
[i
].tail_call_reg
2531 = targetm
.calls
.function_incoming_arg (args_so_far
, arg
);
2533 args
[i
].tail_call_reg
= args
[i
].reg
;
2536 args
[i
].partial
= targetm
.calls
.arg_partial_bytes (args_so_far
, arg
);
2538 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (arg
);
2540 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
2541 it means that we are to pass this arg in the register(s) designated
2542 by the PARALLEL, but also to pass it in the stack. */
2543 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
2544 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
2545 args
[i
].pass_on_stack
= 1;
2547 /* If this is an addressable type, we must preallocate the stack
2548 since we must evaluate the object into its final location.
2550 If this is to be passed in both registers and the stack, it is simpler
2552 if (TREE_ADDRESSABLE (type
)
2553 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
2554 *must_preallocate
= 1;
2556 /* Compute the stack-size of this argument. */
2557 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
2558 || reg_parm_stack_space
> 0
2559 || args
[i
].pass_on_stack
)
2560 locate_and_pad_parm (arg
.mode
, type
,
2561 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2566 reg_parm_stack_space
,
2567 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
2568 fndecl
, args_size
, &args
[i
].locate
);
2569 #ifdef BLOCK_REG_PADDING
2571 /* The argument is passed entirely in registers. See at which
2572 end it should be padded. */
2573 args
[i
].locate
.where_pad
=
2574 BLOCK_REG_PADDING (arg
.mode
, type
,
2575 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
2578 /* Update ARGS_SIZE, the total stack space for args so far. */
2580 args_size
->constant
+= args
[i
].locate
.size
.constant
;
2581 if (args
[i
].locate
.size
.var
)
2582 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
2584 /* Increment ARGS_SO_FAR, which has info about which arg-registers
2585 have been used, etc. */
2587 /* ??? Traditionally we've passed TYPE_MODE here, instead of the
2588 promoted_mode used for function_arg above. However, the
2589 corresponding handling of incoming arguments in function.c
2590 does pass the promoted mode. */
2591 arg
.mode
= TYPE_MODE (type
);
2592 targetm
.calls
.function_arg_advance (args_so_far
, arg
);
2594 /* Store argument values for functions decorated with attribute
2596 if (argpos
== alloc_idx
[0])
2597 alloc_args
[0] = args
[i
].tree_value
;
2598 else if (argpos
== alloc_idx
[1])
2599 alloc_args
[1] = args
[i
].tree_value
;
2601 /* Save the actual argument that corresponds to the access attribute
2602 operand for later processing. */
2603 if (attr_access
*access
= rdwr_idx
.get (argpos
))
2605 if (POINTER_TYPE_P (type
))
2607 access
->ptr
= args
[i
].tree_value
;
2608 // A nonnull ACCESS->SIZE contains VLA bounds. */
2612 access
->size
= args
[i
].tree_value
;
2613 gcc_assert (access
->ptr
== NULL_TREE
);
2620 /* Check the arguments of functions decorated with attribute
2622 maybe_warn_alloc_args_overflow (fndecl
, exp
, alloc_args
, alloc_idx
);
2625 /* Detect passing non-string arguments to functions expecting
2626 nul-terminated strings. */
2627 maybe_warn_nonstring_arg (fndecl
, exp
);
2629 /* Check attribute access arguments. */
2630 maybe_warn_rdwr_sizes (&rdwr_idx
, fndecl
, fntype
, exp
);
2632 /* Check calls to operator new for mismatched forms and attempts
2633 to deallocate unallocated objects. */
2634 maybe_emit_free_warning (exp
);
2637 /* Update ARGS_SIZE to contain the total size for the argument block.
2638 Return the original constant component of the argument block's size.
2640 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
2641 for arguments passed in registers. */
2644 compute_argument_block_size (int reg_parm_stack_space
,
2645 struct args_size
*args_size
,
2646 tree fndecl ATTRIBUTE_UNUSED
,
2647 tree fntype ATTRIBUTE_UNUSED
,
2648 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
2650 poly_int64 unadjusted_args_size
= args_size
->constant
;
2652 /* For accumulate outgoing args mode we don't need to align, since the frame
2653 will be already aligned. Align to STACK_BOUNDARY in order to prevent
2654 backends from generating misaligned frame sizes. */
2655 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
2656 preferred_stack_boundary
= STACK_BOUNDARY
;
2658 /* Compute the actual size of the argument block required. The variable
2659 and constant sizes must be combined, the size may have to be rounded,
2660 and there may be a minimum required size. */
2664 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
2665 args_size
->constant
= 0;
2667 preferred_stack_boundary
/= BITS_PER_UNIT
;
2668 if (preferred_stack_boundary
> 1)
2670 /* We don't handle this case yet. To handle it correctly we have
2671 to add the delta, round and subtract the delta.
2672 Currently no machine description requires this support. */
2673 gcc_assert (multiple_p (stack_pointer_delta
,
2674 preferred_stack_boundary
));
2675 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
2678 if (reg_parm_stack_space
> 0)
2681 = size_binop (MAX_EXPR
, args_size
->var
,
2682 ssize_int (reg_parm_stack_space
));
2684 /* The area corresponding to register parameters is not to count in
2685 the size of the block we need. So make the adjustment. */
2686 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2688 = size_binop (MINUS_EXPR
, args_size
->var
,
2689 ssize_int (reg_parm_stack_space
));
2694 preferred_stack_boundary
/= BITS_PER_UNIT
;
2695 if (preferred_stack_boundary
< 1)
2696 preferred_stack_boundary
= 1;
2697 args_size
->constant
= (aligned_upper_bound (args_size
->constant
2698 + stack_pointer_delta
,
2699 preferred_stack_boundary
)
2700 - stack_pointer_delta
);
2702 args_size
->constant
= upper_bound (args_size
->constant
,
2703 reg_parm_stack_space
);
2705 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2706 args_size
->constant
-= reg_parm_stack_space
;
2708 return unadjusted_args_size
;
2711 /* Precompute parameters as needed for a function call.
2713 FLAGS is mask of ECF_* constants.
2715 NUM_ACTUALS is the number of arguments.
2717 ARGS is an array containing information for each argument; this
2718 routine fills in the INITIAL_VALUE and VALUE fields for each
2719 precomputed argument. */
2722 precompute_arguments (int num_actuals
, struct arg_data
*args
)
2726 /* If this is a libcall, then precompute all arguments so that we do not
2727 get extraneous instructions emitted as part of the libcall sequence. */
2729 /* If we preallocated the stack space, and some arguments must be passed
2730 on the stack, then we must precompute any parameter which contains a
2731 function call which will store arguments on the stack.
2732 Otherwise, evaluating the parameter may clobber previous parameters
2733 which have already been stored into the stack. (we have code to avoid
2734 such case by saving the outgoing stack arguments, but it results in
2736 if (!ACCUMULATE_OUTGOING_ARGS
)
2739 for (i
= 0; i
< num_actuals
; i
++)
2744 if (TREE_CODE (args
[i
].tree_value
) != CALL_EXPR
)
2747 /* If this is an addressable type, we cannot pre-evaluate it. */
2748 type
= TREE_TYPE (args
[i
].tree_value
);
2749 gcc_assert (!TREE_ADDRESSABLE (type
));
2751 args
[i
].initial_value
= args
[i
].value
2752 = expand_normal (args
[i
].tree_value
);
2754 mode
= TYPE_MODE (type
);
2755 if (mode
!= args
[i
].mode
)
2757 int unsignedp
= args
[i
].unsignedp
;
2759 = convert_modes (args
[i
].mode
, mode
,
2760 args
[i
].value
, args
[i
].unsignedp
);
2762 /* CSE will replace this only if it contains args[i].value
2763 pseudo, so convert it down to the declared mode using
2765 if (REG_P (args
[i
].value
)
2766 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
2767 && promote_mode (type
, mode
, &unsignedp
) != args
[i
].mode
)
2769 args
[i
].initial_value
2770 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
2771 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
2772 SUBREG_PROMOTED_SET (args
[i
].initial_value
, args
[i
].unsignedp
);
2778 /* Given the current state of MUST_PREALLOCATE and information about
2779 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
2780 compute and return the final value for MUST_PREALLOCATE. */
2783 finalize_must_preallocate (int must_preallocate
, int num_actuals
,
2784 struct arg_data
*args
, struct args_size
*args_size
)
2786 /* See if we have or want to preallocate stack space.
2788 If we would have to push a partially-in-regs parm
2789 before other stack parms, preallocate stack space instead.
2791 If the size of some parm is not a multiple of the required stack
2792 alignment, we must preallocate.
2794 If the total size of arguments that would otherwise create a copy in
2795 a temporary (such as a CALL) is more than half the total argument list
2796 size, preallocation is faster.
2798 Another reason to preallocate is if we have a machine (like the m88k)
2799 where stack alignment is required to be maintained between every
2800 pair of insns, not just when the call is made. However, we assume here
2801 that such machines either do not have push insns (and hence preallocation
2802 would occur anyway) or the problem is taken care of with
2805 if (! must_preallocate
)
2807 int partial_seen
= 0;
2808 poly_int64 copy_to_evaluate_size
= 0;
2811 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
2813 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
2815 else if (partial_seen
&& args
[i
].reg
== 0)
2816 must_preallocate
= 1;
2818 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
2819 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
2820 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
2821 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
2822 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
2823 copy_to_evaluate_size
2824 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
2827 if (maybe_ne (args_size
->constant
, 0)
2828 && maybe_ge (copy_to_evaluate_size
* 2, args_size
->constant
))
2829 must_preallocate
= 1;
2831 return must_preallocate
;
2834 /* If we preallocated stack space, compute the address of each argument
2835 and store it into the ARGS array.
2837 We need not ensure it is a valid memory address here; it will be
2838 validized when it is used.
2840 ARGBLOCK is an rtx for the address of the outgoing arguments. */
2843 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
2847 rtx arg_reg
= argblock
;
2849 poly_int64 arg_offset
= 0;
2851 if (GET_CODE (argblock
) == PLUS
)
2853 arg_reg
= XEXP (argblock
, 0);
2854 arg_offset
= rtx_to_poly_int64 (XEXP (argblock
, 1));
2857 for (i
= 0; i
< num_actuals
; i
++)
2859 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
2860 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
2862 unsigned int align
, boundary
;
2863 poly_uint64 units_on_stack
= 0;
2864 machine_mode partial_mode
= VOIDmode
;
2866 /* Skip this parm if it will not be passed on the stack. */
2867 if (! args
[i
].pass_on_stack
2869 && args
[i
].partial
== 0)
2872 if (TYPE_EMPTY_P (TREE_TYPE (args
[i
].tree_value
)))
2875 addr
= simplify_gen_binary (PLUS
, Pmode
, arg_reg
, offset
);
2876 addr
= plus_constant (Pmode
, addr
, arg_offset
);
2878 if (args
[i
].partial
!= 0)
2880 /* Only part of the parameter is being passed on the stack.
2881 Generate a simple memory reference of the correct size. */
2882 units_on_stack
= args
[i
].locate
.size
.constant
;
2883 poly_uint64 bits_on_stack
= units_on_stack
* BITS_PER_UNIT
;
2884 partial_mode
= int_mode_for_size (bits_on_stack
, 1).else_blk ();
2885 args
[i
].stack
= gen_rtx_MEM (partial_mode
, addr
);
2886 set_mem_size (args
[i
].stack
, units_on_stack
);
2890 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
2891 set_mem_attributes (args
[i
].stack
,
2892 TREE_TYPE (args
[i
].tree_value
), 1);
2894 align
= BITS_PER_UNIT
;
2895 boundary
= args
[i
].locate
.boundary
;
2896 poly_int64 offset_val
;
2897 if (args
[i
].locate
.where_pad
!= PAD_DOWNWARD
)
2899 else if (poly_int_rtx_p (offset
, &offset_val
))
2901 align
= least_bit_hwi (boundary
);
2902 unsigned int offset_align
2903 = known_alignment (offset_val
) * BITS_PER_UNIT
;
2904 if (offset_align
!= 0)
2905 align
= MIN (align
, offset_align
);
2907 set_mem_align (args
[i
].stack
, align
);
2909 addr
= simplify_gen_binary (PLUS
, Pmode
, arg_reg
, slot_offset
);
2910 addr
= plus_constant (Pmode
, addr
, arg_offset
);
2912 if (args
[i
].partial
!= 0)
2914 /* Only part of the parameter is being passed on the stack.
2915 Generate a simple memory reference of the correct size.
2917 args
[i
].stack_slot
= gen_rtx_MEM (partial_mode
, addr
);
2918 set_mem_size (args
[i
].stack_slot
, units_on_stack
);
2922 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
2923 set_mem_attributes (args
[i
].stack_slot
,
2924 TREE_TYPE (args
[i
].tree_value
), 1);
2926 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
2928 /* Function incoming arguments may overlap with sibling call
2929 outgoing arguments and we cannot allow reordering of reads
2930 from function arguments with stores to outgoing arguments
2931 of sibling calls. */
2932 set_mem_alias_set (args
[i
].stack
, 0);
2933 set_mem_alias_set (args
[i
].stack_slot
, 0);
2938 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
2939 in a call instruction.
2941 FNDECL is the tree node for the target function. For an indirect call
2942 FNDECL will be NULL_TREE.
2944 ADDR is the operand 0 of CALL_EXPR for this call. */
2947 rtx_for_function_call (tree fndecl
, tree addr
)
2951 /* Get the function to call, in the form of RTL. */
2954 if (!TREE_USED (fndecl
) && fndecl
!= current_function_decl
)
2955 TREE_USED (fndecl
) = 1;
2957 /* Get a SYMBOL_REF rtx for the function address. */
2958 funexp
= XEXP (DECL_RTL (fndecl
), 0);
2961 /* Generate an rtx (probably a pseudo-register) for the address. */
2964 funexp
= expand_normal (addr
);
2965 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
2970 /* Return the static chain for this function, if any. */
2973 rtx_for_static_chain (const_tree fndecl_or_type
, bool incoming_p
)
2975 if (DECL_P (fndecl_or_type
) && !DECL_STATIC_CHAIN (fndecl_or_type
))
2978 return targetm
.calls
.static_chain (fndecl_or_type
, incoming_p
);
2981 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
2984 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
2985 or NULL_RTX if none has been scanned yet. */
2986 rtx_insn
*scan_start
;
2987 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
2988 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
2989 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
2990 with fixed offset, or PC if this is with variable or unknown offset. */
2992 } internal_arg_pointer_exp_state
;
2994 static rtx
internal_arg_pointer_based_exp (const_rtx
, bool);
2996 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
2997 the tail call sequence, starting with first insn that hasn't been
2998 scanned yet, and note for each pseudo on the LHS whether it is based
2999 on crtl->args.internal_arg_pointer or not, and what offset from that
3000 that pointer it has. */
3003 internal_arg_pointer_based_exp_scan (void)
3005 rtx_insn
*insn
, *scan_start
= internal_arg_pointer_exp_state
.scan_start
;
3007 if (scan_start
== NULL_RTX
)
3008 insn
= get_insns ();
3010 insn
= NEXT_INSN (scan_start
);
3014 rtx set
= single_set (insn
);
3015 if (set
&& REG_P (SET_DEST (set
)) && !HARD_REGISTER_P (SET_DEST (set
)))
3018 unsigned int idx
= REGNO (SET_DEST (set
)) - FIRST_PSEUDO_REGISTER
;
3019 /* Punt on pseudos set multiple times. */
3020 if (idx
< internal_arg_pointer_exp_state
.cache
.length ()
3021 && (internal_arg_pointer_exp_state
.cache
[idx
]
3025 val
= internal_arg_pointer_based_exp (SET_SRC (set
), false);
3026 if (val
!= NULL_RTX
)
3028 if (idx
>= internal_arg_pointer_exp_state
.cache
.length ())
3029 internal_arg_pointer_exp_state
.cache
3030 .safe_grow_cleared (idx
+ 1, true);
3031 internal_arg_pointer_exp_state
.cache
[idx
] = val
;
3034 if (NEXT_INSN (insn
) == NULL_RTX
)
3036 insn
= NEXT_INSN (insn
);
3039 internal_arg_pointer_exp_state
.scan_start
= scan_start
;
3042 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
3043 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
3044 it with fixed offset, or PC if this is with variable or unknown offset.
3045 TOPLEVEL is true if the function is invoked at the topmost level. */
3048 internal_arg_pointer_based_exp (const_rtx rtl
, bool toplevel
)
3050 if (CONSTANT_P (rtl
))
3053 if (rtl
== crtl
->args
.internal_arg_pointer
)
3056 if (REG_P (rtl
) && HARD_REGISTER_P (rtl
))
3060 if (GET_CODE (rtl
) == PLUS
&& poly_int_rtx_p (XEXP (rtl
, 1), &offset
))
3062 rtx val
= internal_arg_pointer_based_exp (XEXP (rtl
, 0), toplevel
);
3063 if (val
== NULL_RTX
|| val
== pc_rtx
)
3065 return plus_constant (Pmode
, val
, offset
);
3068 /* When called at the topmost level, scan pseudo assignments in between the
3069 last scanned instruction in the tail call sequence and the latest insn
3070 in that sequence. */
3072 internal_arg_pointer_based_exp_scan ();
3076 unsigned int idx
= REGNO (rtl
) - FIRST_PSEUDO_REGISTER
;
3077 if (idx
< internal_arg_pointer_exp_state
.cache
.length ())
3078 return internal_arg_pointer_exp_state
.cache
[idx
];
3083 subrtx_iterator::array_type array
;
3084 FOR_EACH_SUBRTX (iter
, array
, rtl
, NONCONST
)
3086 const_rtx x
= *iter
;
3087 if (REG_P (x
) && internal_arg_pointer_based_exp (x
, false) != NULL_RTX
)
3090 iter
.skip_subrtxes ();
3096 /* Return true if SIZE bytes starting from address ADDR might overlap an
3097 already-clobbered argument area. This function is used to determine
3098 if we should give up a sibcall. */
3101 mem_might_overlap_already_clobbered_arg_p (rtx addr
, poly_uint64 size
)
3104 unsigned HOST_WIDE_INT start
, end
;
3107 if (bitmap_empty_p (stored_args_map
)
3108 && stored_args_watermark
== HOST_WIDE_INT_M1U
)
3110 val
= internal_arg_pointer_based_exp (addr
, true);
3111 if (val
== NULL_RTX
)
3113 else if (!poly_int_rtx_p (val
, &i
))
3116 if (known_eq (size
, 0U))
3119 if (STACK_GROWS_DOWNWARD
)
3120 i
-= crtl
->args
.pretend_args_size
;
3122 i
+= crtl
->args
.pretend_args_size
;
3124 if (ARGS_GROW_DOWNWARD
)
3127 /* We can ignore any references to the function's pretend args,
3128 which at this point would manifest as negative values of I. */
3129 if (known_le (i
, 0) && known_le (size
, poly_uint64 (-i
)))
3132 start
= maybe_lt (i
, 0) ? 0 : constant_lower_bound (i
);
3133 if (!(i
+ size
).is_constant (&end
))
3134 end
= HOST_WIDE_INT_M1U
;
3136 if (end
> stored_args_watermark
)
3139 end
= MIN (end
, SBITMAP_SIZE (stored_args_map
));
3140 for (unsigned HOST_WIDE_INT k
= start
; k
< end
; ++k
)
3141 if (bitmap_bit_p (stored_args_map
, k
))
3147 /* Do the register loads required for any wholly-register parms or any
3148 parms which are passed both on the stack and in a register. Their
3149 expressions were already evaluated.
3151 Mark all register-parms as living through the call, putting these USE
3152 insns in the CALL_INSN_FUNCTION_USAGE field.
3154 When IS_SIBCALL, perform the check_sibcall_argument_overlap
3155 checking, setting *SIBCALL_FAILURE if appropriate. */
3158 load_register_parameters (struct arg_data
*args
, int num_actuals
,
3159 rtx
*call_fusage
, int flags
, int is_sibcall
,
3160 int *sibcall_failure
)
3164 for (i
= 0; i
< num_actuals
; i
++)
3166 rtx reg
= ((flags
& ECF_SIBCALL
)
3167 ? args
[i
].tail_call_reg
: args
[i
].reg
);
3170 int partial
= args
[i
].partial
;
3172 poly_int64 size
= 0;
3173 HOST_WIDE_INT const_size
= 0;
3174 rtx_insn
*before_arg
= get_last_insn ();
3175 tree type
= TREE_TYPE (args
[i
].tree_value
);
3176 if (RECORD_OR_UNION_TYPE_P (type
) && TYPE_TRANSPARENT_AGGR (type
))
3177 type
= TREE_TYPE (first_field (type
));
3178 /* Set non-negative if we must move a word at a time, even if
3179 just one word (e.g, partial == 4 && mode == DFmode). Set
3180 to -1 if we just use a normal move insn. This value can be
3181 zero if the argument is a zero size structure. */
3183 if (GET_CODE (reg
) == PARALLEL
)
3187 gcc_assert (partial
% UNITS_PER_WORD
== 0);
3188 nregs
= partial
/ UNITS_PER_WORD
;
3190 else if (TYPE_MODE (type
) == BLKmode
)
3192 /* Variable-sized parameters should be described by a
3193 PARALLEL instead. */
3194 const_size
= int_size_in_bytes (type
);
3195 gcc_assert (const_size
>= 0);
3196 nregs
= (const_size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
3200 size
= GET_MODE_SIZE (args
[i
].mode
);
3202 /* Handle calls that pass values in multiple non-contiguous
3203 locations. The Irix 6 ABI has examples of this. */
3205 if (GET_CODE (reg
) == PARALLEL
)
3206 emit_group_move (reg
, args
[i
].parallel_value
);
3208 /* If simple case, just do move. If normal partial, store_one_arg
3209 has already loaded the register for us. In all other cases,
3210 load the register(s) from memory. */
3212 else if (nregs
== -1)
3214 emit_move_insn (reg
, args
[i
].value
);
3215 #ifdef BLOCK_REG_PADDING
3216 /* Handle case where we have a value that needs shifting
3217 up to the msb. eg. a QImode value and we're padding
3218 upward on a BYTES_BIG_ENDIAN machine. */
3219 if (args
[i
].locate
.where_pad
3220 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
))
3222 gcc_checking_assert (ordered_p (size
, UNITS_PER_WORD
));
3223 if (maybe_lt (size
, UNITS_PER_WORD
))
3227 = (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
3229 /* Assigning REG here rather than a temp makes
3230 CALL_FUSAGE report the whole reg as used.
3231 Strictly speaking, the call only uses SIZE
3232 bytes at the msb end, but it doesn't seem worth
3233 generating rtl to say that. */
3234 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
3235 x
= expand_shift (LSHIFT_EXPR
, word_mode
,
3236 reg
, shift
, reg
, 1);
3238 emit_move_insn (reg
, x
);
3244 /* If we have pre-computed the values to put in the registers in
3245 the case of non-aligned structures, copy them in now. */
3247 else if (args
[i
].n_aligned_regs
!= 0)
3248 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
3249 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
3250 args
[i
].aligned_regs
[j
]);
3252 else if (partial
== 0 || args
[i
].pass_on_stack
)
3254 /* SIZE and CONST_SIZE are 0 for partial arguments and
3255 the size of a BLKmode type otherwise. */
3256 gcc_checking_assert (known_eq (size
, const_size
));
3257 rtx mem
= validize_mem (copy_rtx (args
[i
].value
));
3259 /* Check for overlap with already clobbered argument area,
3260 providing that this has non-zero size. */
3263 && (mem_might_overlap_already_clobbered_arg_p
3264 (XEXP (args
[i
].value
, 0), const_size
)))
3265 *sibcall_failure
= 1;
3267 if (const_size
% UNITS_PER_WORD
== 0
3268 || MEM_ALIGN (mem
) % BITS_PER_WORD
== 0)
3269 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
3273 move_block_to_reg (REGNO (reg
), mem
, nregs
- 1,
3275 rtx dest
= gen_rtx_REG (word_mode
, REGNO (reg
) + nregs
- 1);
3276 unsigned int bitoff
= (nregs
- 1) * BITS_PER_WORD
;
3277 unsigned int bitsize
= const_size
* BITS_PER_UNIT
- bitoff
;
3278 rtx x
= extract_bit_field (mem
, bitsize
, bitoff
, 1, dest
,
3279 word_mode
, word_mode
, false,
3281 if (BYTES_BIG_ENDIAN
)
3282 x
= expand_shift (LSHIFT_EXPR
, word_mode
, x
,
3283 BITS_PER_WORD
- bitsize
, dest
, 1);
3285 emit_move_insn (dest
, x
);
3288 /* Handle a BLKmode that needs shifting. */
3289 if (nregs
== 1 && const_size
< UNITS_PER_WORD
3290 #ifdef BLOCK_REG_PADDING
3291 && args
[i
].locate
.where_pad
== PAD_DOWNWARD
3297 rtx dest
= gen_rtx_REG (word_mode
, REGNO (reg
));
3298 int shift
= (UNITS_PER_WORD
- const_size
) * BITS_PER_UNIT
;
3299 enum tree_code dir
= (BYTES_BIG_ENDIAN
3300 ? RSHIFT_EXPR
: LSHIFT_EXPR
);
3303 x
= expand_shift (dir
, word_mode
, dest
, shift
, dest
, 1);
3305 emit_move_insn (dest
, x
);
3309 /* When a parameter is a block, and perhaps in other cases, it is
3310 possible that it did a load from an argument slot that was
3311 already clobbered. */
3313 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
3314 *sibcall_failure
= 1;
3316 /* Handle calls that pass values in multiple non-contiguous
3317 locations. The Irix 6 ABI has examples of this. */
3318 if (GET_CODE (reg
) == PARALLEL
)
3319 use_group_regs (call_fusage
, reg
);
3320 else if (nregs
== -1)
3321 use_reg_mode (call_fusage
, reg
, TYPE_MODE (type
));
3323 use_regs (call_fusage
, REGNO (reg
), nregs
);
3328 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
3329 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
3330 bytes, then we would need to push some additional bytes to pad the
3331 arguments. So, we try to compute an adjust to the stack pointer for an
3332 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
3333 bytes. Then, when the arguments are pushed the stack will be perfectly
3336 Return true if this optimization is possible, storing the adjustment
3337 in ADJUSTMENT_OUT and setting ARGS_SIZE->CONSTANT to the number of
3338 bytes that should be popped after the call. */
3341 combine_pending_stack_adjustment_and_call (poly_int64_pod
*adjustment_out
,
3342 poly_int64 unadjusted_args_size
,
3343 struct args_size
*args_size
,
3344 unsigned int preferred_unit_stack_boundary
)
3346 /* The number of bytes to pop so that the stack will be
3347 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
3348 poly_int64 adjustment
;
3349 /* The alignment of the stack after the arguments are pushed, if we
3350 just pushed the arguments without adjust the stack here. */
3351 unsigned HOST_WIDE_INT unadjusted_alignment
;
3353 if (!known_misalignment (stack_pointer_delta
+ unadjusted_args_size
,
3354 preferred_unit_stack_boundary
,
3355 &unadjusted_alignment
))
3358 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
3359 as possible -- leaving just enough left to cancel out the
3360 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
3361 PENDING_STACK_ADJUST is non-negative, and congruent to
3362 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
3364 /* Begin by trying to pop all the bytes. */
3365 unsigned HOST_WIDE_INT tmp_misalignment
;
3366 if (!known_misalignment (pending_stack_adjust
,
3367 preferred_unit_stack_boundary
,
3370 unadjusted_alignment
-= tmp_misalignment
;
3371 adjustment
= pending_stack_adjust
;
3372 /* Push enough additional bytes that the stack will be aligned
3373 after the arguments are pushed. */
3374 if (preferred_unit_stack_boundary
> 1 && unadjusted_alignment
)
3375 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
3377 /* We need to know whether the adjusted argument size
3378 (UNADJUSTED_ARGS_SIZE - ADJUSTMENT) constitutes an allocation
3379 or a deallocation. */
3380 if (!ordered_p (adjustment
, unadjusted_args_size
))
3383 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
3384 bytes after the call. The right number is the entire
3385 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
3386 by the arguments in the first place. */
3388 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
3390 *adjustment_out
= adjustment
;
3394 /* Scan X expression if it does not dereference any argument slots
3395 we already clobbered by tail call arguments (as noted in stored_args_map
3397 Return nonzero if X expression dereferences such argument slots,
3401 check_sibcall_argument_overlap_1 (rtx x
)
3410 code
= GET_CODE (x
);
3412 /* We need not check the operands of the CALL expression itself. */
3417 return (mem_might_overlap_already_clobbered_arg_p
3418 (XEXP (x
, 0), GET_MODE_SIZE (GET_MODE (x
))));
3420 /* Scan all subexpressions. */
3421 fmt
= GET_RTX_FORMAT (code
);
3422 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
3426 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
3429 else if (*fmt
== 'E')
3431 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
3432 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
3439 /* Scan sequence after INSN if it does not dereference any argument slots
3440 we already clobbered by tail call arguments (as noted in stored_args_map
3441 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
3442 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
3443 should be 0). Return nonzero if sequence after INSN dereferences such argument
3444 slots, zero otherwise. */
3447 check_sibcall_argument_overlap (rtx_insn
*insn
, struct arg_data
*arg
,
3448 int mark_stored_args_map
)
3450 poly_uint64 low
, high
;
3451 unsigned HOST_WIDE_INT const_low
, const_high
;
3453 if (insn
== NULL_RTX
)
3454 insn
= get_insns ();
3456 insn
= NEXT_INSN (insn
);
3458 for (; insn
; insn
= NEXT_INSN (insn
))
3460 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
3463 if (mark_stored_args_map
)
3465 if (ARGS_GROW_DOWNWARD
)
3466 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
3468 low
= arg
->locate
.slot_offset
.constant
;
3469 high
= low
+ arg
->locate
.size
.constant
;
3471 const_low
= constant_lower_bound (low
);
3472 if (high
.is_constant (&const_high
))
3473 for (unsigned HOST_WIDE_INT i
= const_low
; i
< const_high
; ++i
)
3474 bitmap_set_bit (stored_args_map
, i
);
3476 stored_args_watermark
= MIN (stored_args_watermark
, const_low
);
3478 return insn
!= NULL_RTX
;
3481 /* Given that a function returns a value of mode MODE at the most
3482 significant end of hard register VALUE, shift VALUE left or right
3483 as specified by LEFT_P. Return true if some action was needed. */
3486 shift_return_value (machine_mode mode
, bool left_p
, rtx value
)
3488 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
3489 machine_mode value_mode
= GET_MODE (value
);
3490 poly_int64 shift
= GET_MODE_BITSIZE (value_mode
) - GET_MODE_BITSIZE (mode
);
3492 if (known_eq (shift
, 0))
3495 /* Use ashr rather than lshr for right shifts. This is for the benefit
3496 of the MIPS port, which requires SImode values to be sign-extended
3497 when stored in 64-bit registers. */
3498 if (!force_expand_binop (value_mode
, left_p
? ashl_optab
: ashr_optab
,
3499 value
, gen_int_shift_amount (value_mode
, shift
),
3500 value
, 1, OPTAB_WIDEN
))
3505 /* If X is a likely-spilled register value, copy it to a pseudo
3506 register and return that register. Return X otherwise. */
3509 avoid_likely_spilled_reg (rtx x
)
3514 && HARD_REGISTER_P (x
)
3515 && targetm
.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x
))))
3517 /* Make sure that we generate a REG rather than a CONCAT.
3518 Moves into CONCATs can need nontrivial instructions,
3519 and the whole point of this function is to avoid
3520 using the hard register directly in such a situation. */
3521 generating_concat_p
= 0;
3522 new_rtx
= gen_reg_rtx (GET_MODE (x
));
3523 generating_concat_p
= 1;
3524 emit_move_insn (new_rtx
, x
);
3530 /* Helper function for expand_call.
3531 Return false is EXP is not implementable as a sibling call. */
3534 can_implement_as_sibling_call_p (tree exp
,
3535 rtx structure_value_addr
,
3540 const args_size
&args_size
)
3542 if (!targetm
.have_sibcall_epilogue ())
3544 maybe_complain_about_tail_call
3546 "machine description does not have"
3547 " a sibcall_epilogue instruction pattern");
3551 /* Doing sibling call optimization needs some work, since
3552 structure_value_addr can be allocated on the stack.
3553 It does not seem worth the effort since few optimizable
3554 sibling calls will return a structure. */
3555 if (structure_value_addr
!= NULL_RTX
)
3557 maybe_complain_about_tail_call (exp
, "callee returns a structure");
3561 /* Check whether the target is able to optimize the call
3563 if (!targetm
.function_ok_for_sibcall (fndecl
, exp
))
3565 maybe_complain_about_tail_call (exp
,
3566 "target is not able to optimize the"
3567 " call into a sibling call");
3571 /* Functions that do not return exactly once may not be sibcall
3573 if (flags
& ECF_RETURNS_TWICE
)
3575 maybe_complain_about_tail_call (exp
, "callee returns twice");
3578 if (flags
& ECF_NORETURN
)
3580 maybe_complain_about_tail_call (exp
, "callee does not return");
3584 if (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
))))
3586 maybe_complain_about_tail_call (exp
, "volatile function type");
3590 /* If the called function is nested in the current one, it might access
3591 some of the caller's arguments, but could clobber them beforehand if
3592 the argument areas are shared. */
3593 if (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
3595 maybe_complain_about_tail_call (exp
, "nested function");
3599 /* If this function requires more stack slots than the current
3600 function, we cannot change it into a sibling call.
3601 crtl->args.pretend_args_size is not part of the
3602 stack allocated by our caller. */
3603 if (maybe_gt (args_size
.constant
,
3604 crtl
->args
.size
- crtl
->args
.pretend_args_size
))
3606 maybe_complain_about_tail_call (exp
,
3607 "callee required more stack slots"
3608 " than the caller");
3612 /* If the callee pops its own arguments, then it must pop exactly
3613 the same number of arguments as the current function. */
3614 if (maybe_ne (targetm
.calls
.return_pops_args (fndecl
, funtype
,
3615 args_size
.constant
),
3616 targetm
.calls
.return_pops_args (current_function_decl
,
3618 (current_function_decl
),
3621 maybe_complain_about_tail_call (exp
,
3622 "inconsistent number of"
3623 " popped arguments");
3627 if (!lang_hooks
.decls
.ok_for_sibcall (fndecl
))
3629 maybe_complain_about_tail_call (exp
, "frontend does not support"
3634 /* All checks passed. */
3638 /* Update stack alignment when the parameter is passed in the stack
3639 since the outgoing parameter requires extra alignment on the calling
3643 update_stack_alignment_for_call (struct locate_and_pad_arg_data
*locate
)
3645 if (crtl
->stack_alignment_needed
< locate
->boundary
)
3646 crtl
->stack_alignment_needed
= locate
->boundary
;
3647 if (crtl
->preferred_stack_boundary
< locate
->boundary
)
3648 crtl
->preferred_stack_boundary
= locate
->boundary
;
3651 /* Generate all the code for a CALL_EXPR exp
3652 and return an rtx for its value.
3653 Store the value in TARGET (specified as an rtx) if convenient.
3654 If the value is stored in TARGET then TARGET is returned.
3655 If IGNORE is nonzero, then we ignore the value of the function call. */
3658 expand_call (tree exp
, rtx target
, int ignore
)
3660 /* Nonzero if we are currently expanding a call. */
3661 static int currently_expanding_call
= 0;
3663 /* RTX for the function to be called. */
3665 /* Sequence of insns to perform a normal "call". */
3666 rtx_insn
*normal_call_insns
= NULL
;
3667 /* Sequence of insns to perform a tail "call". */
3668 rtx_insn
*tail_call_insns
= NULL
;
3669 /* Data type of the function. */
3671 tree type_arg_types
;
3673 /* Declaration of the function being called,
3674 or 0 if the function is computed (not known by name). */
3676 /* The type of the function being called. */
3678 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
3679 bool must_tail_call
= CALL_EXPR_MUST_TAIL_CALL (exp
);
3682 /* Register in which non-BLKmode value will be returned,
3683 or 0 if no value or if value is BLKmode. */
3685 /* Address where we should return a BLKmode value;
3686 0 if value not BLKmode. */
3687 rtx structure_value_addr
= 0;
3688 /* Nonzero if that address is being passed by treating it as
3689 an extra, implicit first parameter. Otherwise,
3690 it is passed by being copied directly into struct_value_rtx. */
3691 int structure_value_addr_parm
= 0;
3692 /* Holds the value of implicit argument for the struct value. */
3693 tree structure_value_addr_value
= NULL_TREE
;
3694 /* Size of aggregate value wanted, or zero if none wanted
3695 or if we are using the non-reentrant PCC calling convention
3696 or expecting the value in registers. */
3697 poly_int64 struct_value_size
= 0;
3698 /* Nonzero if called function returns an aggregate in memory PCC style,
3699 by returning the address of where to find it. */
3700 int pcc_struct_value
= 0;
3701 rtx struct_value
= 0;
3703 /* Number of actual parameters in this call, including struct value addr. */
3705 /* Number of named args. Args after this are anonymous ones
3706 and they must all go on the stack. */
3708 /* Number of complex actual arguments that need to be split. */
3709 int num_complex_actuals
= 0;
3711 /* Vector of information about each argument.
3712 Arguments are numbered in the order they will be pushed,
3713 not the order they are written. */
3714 struct arg_data
*args
;
3716 /* Total size in bytes of all the stack-parms scanned so far. */
3717 struct args_size args_size
;
3718 struct args_size adjusted_args_size
;
3719 /* Size of arguments before any adjustments (such as rounding). */
3720 poly_int64 unadjusted_args_size
;
3721 /* Data on reg parms scanned so far. */
3722 CUMULATIVE_ARGS args_so_far_v
;
3723 cumulative_args_t args_so_far
;
3724 /* Nonzero if a reg parm has been scanned. */
3726 /* Nonzero if this is an indirect function call. */
3728 /* Nonzero if we must avoid push-insns in the args for this call.
3729 If stack space is allocated for register parameters, but not by the
3730 caller, then it is preallocated in the fixed part of the stack frame.
3731 So the entire argument block must then be preallocated (i.e., we
3732 ignore PUSH_ROUNDING in that case). */
3734 int must_preallocate
= !targetm
.calls
.push_argument (0);
3736 /* Size of the stack reserved for parameter registers. */
3737 int reg_parm_stack_space
= 0;
3739 /* Address of space preallocated for stack parms
3740 (on machines that lack push insns), or 0 if space not preallocated. */
3743 /* Mask of ECF_ and ERF_ flags. */
3745 int return_flags
= 0;
3746 #ifdef REG_PARM_STACK_SPACE
3747 /* Define the boundary of the register parm stack space that needs to be
3749 int low_to_save
, high_to_save
;
3750 rtx save_area
= 0; /* Place that it is saved */
3753 unsigned int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3754 char *initial_stack_usage_map
= stack_usage_map
;
3755 unsigned HOST_WIDE_INT initial_stack_usage_watermark
= stack_usage_watermark
;
3756 char *stack_usage_map_buf
= NULL
;
3758 poly_int64 old_stack_allocated
;
3760 /* State variables to track stack modifications. */
3761 rtx old_stack_level
= 0;
3762 int old_stack_arg_under_construction
= 0;
3763 poly_int64 old_pending_adj
= 0;
3764 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3766 /* Some stack pointer alterations we make are performed via
3767 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
3768 which we then also need to save/restore along the way. */
3769 poly_int64 old_stack_pointer_delta
= 0;
3772 tree addr
= CALL_EXPR_FN (exp
);
3774 /* The alignment of the stack, in bits. */
3775 unsigned HOST_WIDE_INT preferred_stack_boundary
;
3776 /* The alignment of the stack, in bytes. */
3777 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
3778 /* The static chain value to use for this call. */
3779 rtx static_chain_value
;
3780 /* See if this is "nothrow" function call. */
3781 if (TREE_NOTHROW (exp
))
3782 flags
|= ECF_NOTHROW
;
3784 /* See if we can find a DECL-node for the actual function, and get the
3785 function attributes (flags) from the function decl or type node. */
3786 fndecl
= get_callee_fndecl (exp
);
3789 fntype
= TREE_TYPE (fndecl
);
3790 flags
|= flags_from_decl_or_type (fndecl
);
3791 return_flags
|= decl_return_flags (fndecl
);
3795 fntype
= TREE_TYPE (TREE_TYPE (addr
));
3796 flags
|= flags_from_decl_or_type (fntype
);
3797 if (CALL_EXPR_BY_DESCRIPTOR (exp
))
3798 flags
|= ECF_BY_DESCRIPTOR
;
3800 rettype
= TREE_TYPE (exp
);
3802 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
3804 /* Warn if this value is an aggregate type,
3805 regardless of which calling convention we are using for it. */
3806 if (AGGREGATE_TYPE_P (rettype
))
3807 warning (OPT_Waggregate_return
, "function call has aggregate value");
3809 /* If the result of a non looping pure or const function call is
3810 ignored (or void), and none of its arguments are volatile, we can
3811 avoid expanding the call and just evaluate the arguments for
3813 if ((flags
& (ECF_CONST
| ECF_PURE
))
3814 && (!(flags
& ECF_LOOPING_CONST_OR_PURE
))
3815 && (flags
& ECF_NOTHROW
)
3816 && (ignore
|| target
== const0_rtx
3817 || TYPE_MODE (rettype
) == VOIDmode
))
3819 bool volatilep
= false;
3821 call_expr_arg_iterator iter
;
3823 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3824 if (TREE_THIS_VOLATILE (arg
))
3832 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3833 expand_expr (arg
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
3838 #ifdef REG_PARM_STACK_SPACE
3839 reg_parm_stack_space
= REG_PARM_STACK_SPACE (!fndecl
? fntype
: fndecl
);
3842 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
3843 && reg_parm_stack_space
> 0 && targetm
.calls
.push_argument (0))
3844 must_preallocate
= 1;
3846 /* Set up a place to return a structure. */
3848 /* Cater to broken compilers. */
3849 if (aggregate_value_p (exp
, fntype
))
3851 /* This call returns a big structure. */
3852 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
3854 #ifdef PCC_STATIC_STRUCT_RETURN
3856 pcc_struct_value
= 1;
3858 #else /* not PCC_STATIC_STRUCT_RETURN */
3860 if (!poly_int_tree_p (TYPE_SIZE_UNIT (rettype
), &struct_value_size
))
3861 struct_value_size
= -1;
3863 /* Even if it is semantically safe to use the target as the return
3864 slot, it may be not sufficiently aligned for the return type. */
3865 if (CALL_EXPR_RETURN_SLOT_OPT (exp
)
3868 /* If rettype is addressable, we may not create a temporary.
3869 If target is properly aligned at runtime and the compiler
3870 just doesn't know about it, it will work fine, otherwise it
3872 && (TREE_ADDRESSABLE (rettype
)
3873 || !(MEM_ALIGN (target
) < TYPE_ALIGN (rettype
)
3874 && targetm
.slow_unaligned_access (TYPE_MODE (rettype
),
3875 MEM_ALIGN (target
)))))
3876 structure_value_addr
= XEXP (target
, 0);
3879 /* For variable-sized objects, we must be called with a target
3880 specified. If we were to allocate space on the stack here,
3881 we would have no way of knowing when to free it. */
3882 rtx d
= assign_temp (rettype
, 1, 1);
3883 structure_value_addr
= XEXP (d
, 0);
3887 #endif /* not PCC_STATIC_STRUCT_RETURN */
3890 /* Figure out the amount to which the stack should be aligned. */
3891 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3894 struct cgraph_rtl_info
*i
= cgraph_node::rtl_info (fndecl
);
3895 /* Without automatic stack alignment, we can't increase preferred
3896 stack boundary. With automatic stack alignment, it is
3897 unnecessary since unless we can guarantee that all callers will
3898 align the outgoing stack properly, callee has to align its
3901 && i
->preferred_incoming_stack_boundary
3902 && i
->preferred_incoming_stack_boundary
< preferred_stack_boundary
)
3903 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
3906 /* Operand 0 is a pointer-to-function; get the type of the function. */
3907 funtype
= TREE_TYPE (addr
);
3908 gcc_assert (POINTER_TYPE_P (funtype
));
3909 funtype
= TREE_TYPE (funtype
);
3911 /* Count whether there are actual complex arguments that need to be split
3912 into their real and imaginary parts. Munge the type_arg_types
3913 appropriately here as well. */
3914 if (targetm
.calls
.split_complex_arg
)
3916 call_expr_arg_iterator iter
;
3918 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3920 tree type
= TREE_TYPE (arg
);
3921 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
3922 && targetm
.calls
.split_complex_arg (type
))
3923 num_complex_actuals
++;
3925 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
3928 type_arg_types
= TYPE_ARG_TYPES (funtype
);
3930 if (flags
& ECF_MAY_BE_ALLOCA
)
3931 cfun
->calls_alloca
= 1;
3933 /* If struct_value_rtx is 0, it means pass the address
3934 as if it were an extra parameter. Put the argument expression
3935 in structure_value_addr_value. */
3936 if (structure_value_addr
&& struct_value
== 0)
3938 /* If structure_value_addr is a REG other than
3939 virtual_outgoing_args_rtx, we can use always use it. If it
3940 is not a REG, we must always copy it into a register.
3941 If it is virtual_outgoing_args_rtx, we must copy it to another
3942 register in some cases. */
3943 rtx temp
= (!REG_P (structure_value_addr
)
3944 || (ACCUMULATE_OUTGOING_ARGS
3945 && stack_arg_under_construction
3946 && structure_value_addr
== virtual_outgoing_args_rtx
)
3947 ? copy_addr_to_reg (convert_memory_address
3948 (Pmode
, structure_value_addr
))
3949 : structure_value_addr
);
3951 structure_value_addr_value
=
3952 make_tree (build_pointer_type (TREE_TYPE (funtype
)), temp
);
3953 structure_value_addr_parm
= 1;
3956 /* Count the arguments and set NUM_ACTUALS. */
3958 call_expr_nargs (exp
) + num_complex_actuals
+ structure_value_addr_parm
;
3960 /* Compute number of named args.
3961 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
3963 if (type_arg_types
!= 0)
3965 = (list_length (type_arg_types
)
3966 /* Count the struct value address, if it is passed as a parm. */
3967 + structure_value_addr_parm
);
3969 /* If we know nothing, treat all args as named. */
3970 n_named_args
= num_actuals
;
3972 /* Start updating where the next arg would go.
3974 On some machines (such as the PA) indirect calls have a different
3975 calling convention than normal calls. The fourth argument in
3976 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
3978 INIT_CUMULATIVE_ARGS (args_so_far_v
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
3979 args_so_far
= pack_cumulative_args (&args_so_far_v
);
3981 /* Now possibly adjust the number of named args.
3982 Normally, don't include the last named arg if anonymous args follow.
3983 We do include the last named arg if
3984 targetm.calls.strict_argument_naming() returns nonzero.
3985 (If no anonymous args follow, the result of list_length is actually
3986 one too large. This is harmless.)
3988 If targetm.calls.pretend_outgoing_varargs_named() returns
3989 nonzero, and targetm.calls.strict_argument_naming() returns zero,
3990 this machine will be able to place unnamed args that were passed
3991 in registers into the stack. So treat all args as named. This
3992 allows the insns emitting for a specific argument list to be
3993 independent of the function declaration.
3995 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
3996 we do not have any reliable way to pass unnamed args in
3997 registers, so we must force them into memory. */
3999 if (type_arg_types
!= 0
4000 && targetm
.calls
.strict_argument_naming (args_so_far
))
4002 else if (type_arg_types
!= 0
4003 && ! targetm
.calls
.pretend_outgoing_varargs_named (args_so_far
))
4004 /* Don't include the last named arg. */
4007 /* Treat all args as named. */
4008 n_named_args
= num_actuals
;
4010 /* Make a vector to hold all the information about each arg. */
4011 args
= XCNEWVEC (struct arg_data
, num_actuals
);
4013 /* Build up entries in the ARGS array, compute the size of the
4014 arguments into ARGS_SIZE, etc. */
4015 initialize_argument_information (num_actuals
, args
, &args_size
,
4017 structure_value_addr_value
, fndecl
, fntype
,
4018 args_so_far
, reg_parm_stack_space
,
4019 &old_stack_level
, &old_pending_adj
,
4020 &must_preallocate
, &flags
,
4021 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
4024 must_preallocate
= 1;
4026 /* Now make final decision about preallocating stack space. */
4027 must_preallocate
= finalize_must_preallocate (must_preallocate
,
4031 /* If the structure value address will reference the stack pointer, we
4032 must stabilize it. We don't need to do this if we know that we are
4033 not going to adjust the stack pointer in processing this call. */
4035 if (structure_value_addr
4036 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
4037 || reg_mentioned_p (virtual_outgoing_args_rtx
,
4038 structure_value_addr
))
4040 || (!ACCUMULATE_OUTGOING_ARGS
4041 && maybe_ne (args_size
.constant
, 0))))
4042 structure_value_addr
= copy_to_reg (structure_value_addr
);
4044 /* Tail calls can make things harder to debug, and we've traditionally
4045 pushed these optimizations into -O2. Don't try if we're already
4046 expanding a call, as that means we're an argument. Don't try if
4047 there's cleanups, as we know there's code to follow the call. */
4048 if (currently_expanding_call
++ != 0
4049 || (!flag_optimize_sibling_calls
&& !CALL_FROM_THUNK_P (exp
))
4051 || dbg_cnt (tail_call
) == false)
4054 /* Workaround buggy C/C++ wrappers around Fortran routines with
4055 character(len=constant) arguments if the hidden string length arguments
4056 are passed on the stack; if the callers forget to pass those arguments,
4057 attempting to tail call in such routines leads to stack corruption.
4058 Avoid tail calls in functions where at least one such hidden string
4059 length argument is passed (partially or fully) on the stack in the
4060 caller and the callee needs to pass any arguments on the stack.
4062 if (try_tail_call
&& maybe_ne (args_size
.constant
, 0))
4063 for (tree arg
= DECL_ARGUMENTS (current_function_decl
);
4064 arg
; arg
= DECL_CHAIN (arg
))
4065 if (DECL_HIDDEN_STRING_LENGTH (arg
) && DECL_INCOMING_RTL (arg
))
4067 subrtx_iterator::array_type array
;
4068 FOR_EACH_SUBRTX (iter
, array
, DECL_INCOMING_RTL (arg
), NONCONST
)
4076 /* If the user has marked the function as requiring tail-call
4077 optimization, attempt it. */
4081 /* Rest of purposes for tail call optimizations to fail. */
4083 try_tail_call
= can_implement_as_sibling_call_p (exp
,
4084 structure_value_addr
,
4087 flags
, addr
, args_size
);
4089 /* Check if caller and callee disagree in promotion of function
4093 machine_mode caller_mode
, caller_promoted_mode
;
4094 machine_mode callee_mode
, callee_promoted_mode
;
4095 int caller_unsignedp
, callee_unsignedp
;
4096 tree caller_res
= DECL_RESULT (current_function_decl
);
4098 caller_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (caller_res
));
4099 caller_mode
= DECL_MODE (caller_res
);
4100 callee_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (funtype
));
4101 callee_mode
= TYPE_MODE (TREE_TYPE (funtype
));
4102 caller_promoted_mode
4103 = promote_function_mode (TREE_TYPE (caller_res
), caller_mode
,
4105 TREE_TYPE (current_function_decl
), 1);
4106 callee_promoted_mode
4107 = promote_function_mode (TREE_TYPE (funtype
), callee_mode
,
4110 if (caller_mode
!= VOIDmode
4111 && (caller_promoted_mode
!= callee_promoted_mode
4112 || ((caller_mode
!= caller_promoted_mode
4113 || callee_mode
!= callee_promoted_mode
)
4114 && (caller_unsignedp
!= callee_unsignedp
4115 || partial_subreg_p (caller_mode
, callee_mode
)))))
4118 maybe_complain_about_tail_call (exp
,
4119 "caller and callee disagree in"
4120 " promotion of function"
4125 /* Ensure current function's preferred stack boundary is at least
4126 what we need. Stack alignment may also increase preferred stack
4128 for (i
= 0; i
< num_actuals
; i
++)
4129 if (reg_parm_stack_space
> 0
4131 || args
[i
].partial
!= 0
4132 || args
[i
].pass_on_stack
)
4133 update_stack_alignment_for_call (&args
[i
].locate
);
4134 if (crtl
->preferred_stack_boundary
< preferred_stack_boundary
)
4135 crtl
->preferred_stack_boundary
= preferred_stack_boundary
;
4137 preferred_stack_boundary
= crtl
->preferred_stack_boundary
;
4139 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
4141 if (flag_callgraph_info
)
4142 record_final_call (fndecl
, EXPR_LOCATION (exp
));
4144 /* We want to make two insn chains; one for a sibling call, the other
4145 for a normal call. We will select one of the two chains after
4146 initial RTL generation is complete. */
4147 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
4149 int sibcall_failure
= 0;
4150 /* We want to emit any pending stack adjustments before the tail
4151 recursion "call". That way we know any adjustment after the tail
4152 recursion call can be ignored if we indeed use the tail
4154 saved_pending_stack_adjust save
;
4155 rtx_insn
*insns
, *before_call
, *after_args
;
4160 /* State variables we need to save and restore between
4162 save_pending_stack_adjust (&save
);
4165 flags
&= ~ECF_SIBCALL
;
4167 flags
|= ECF_SIBCALL
;
4169 /* Other state variables that we must reinitialize each time
4170 through the loop (that are not initialized by the loop itself). */
4174 /* Start a new sequence for the normal call case.
4176 From this point on, if the sibling call fails, we want to set
4177 sibcall_failure instead of continuing the loop. */
4180 /* Don't let pending stack adjusts add up to too much.
4181 Also, do all pending adjustments now if there is any chance
4182 this might be a call to alloca or if we are expanding a sibling
4184 Also do the adjustments before a throwing call, otherwise
4185 exception handling can fail; PR 19225. */
4186 if (maybe_ge (pending_stack_adjust
, 32)
4187 || (maybe_ne (pending_stack_adjust
, 0)
4188 && (flags
& ECF_MAY_BE_ALLOCA
))
4189 || (maybe_ne (pending_stack_adjust
, 0)
4190 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
4192 do_pending_stack_adjust ();
4194 /* Precompute any arguments as needed. */
4196 precompute_arguments (num_actuals
, args
);
4198 /* Now we are about to start emitting insns that can be deleted
4199 if a libcall is deleted. */
4200 if (pass
&& (flags
& ECF_MALLOC
))
4204 && crtl
->stack_protect_guard
4205 && targetm
.stack_protect_runtime_enabled_p ())
4206 stack_protect_epilogue ();
4208 adjusted_args_size
= args_size
;
4209 /* Compute the actual size of the argument block required. The variable
4210 and constant sizes must be combined, the size may have to be rounded,
4211 and there may be a minimum required size. When generating a sibcall
4212 pattern, do not round up, since we'll be re-using whatever space our
4214 unadjusted_args_size
4215 = compute_argument_block_size (reg_parm_stack_space
,
4216 &adjusted_args_size
,
4219 : preferred_stack_boundary
));
4221 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
4223 /* The argument block when performing a sibling call is the
4224 incoming argument block. */
4227 argblock
= crtl
->args
.internal_arg_pointer
;
4228 if (STACK_GROWS_DOWNWARD
)
4230 = plus_constant (Pmode
, argblock
, crtl
->args
.pretend_args_size
);
4233 = plus_constant (Pmode
, argblock
, -crtl
->args
.pretend_args_size
);
4235 HOST_WIDE_INT map_size
= constant_lower_bound (args_size
.constant
);
4236 stored_args_map
= sbitmap_alloc (map_size
);
4237 bitmap_clear (stored_args_map
);
4238 stored_args_watermark
= HOST_WIDE_INT_M1U
;
4241 /* If we have no actual push instructions, or shouldn't use them,
4242 make space for all args right now. */
4243 else if (adjusted_args_size
.var
!= 0)
4245 if (old_stack_level
== 0)
4247 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
4248 old_stack_pointer_delta
= stack_pointer_delta
;
4249 old_pending_adj
= pending_stack_adjust
;
4250 pending_stack_adjust
= 0;
4251 /* stack_arg_under_construction says whether a stack arg is
4252 being constructed at the old stack level. Pushing the stack
4253 gets a clean outgoing argument block. */
4254 old_stack_arg_under_construction
= stack_arg_under_construction
;
4255 stack_arg_under_construction
= 0;
4257 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
4258 if (flag_stack_usage_info
)
4259 current_function_has_unbounded_dynamic_stack_size
= 1;
4263 /* Note that we must go through the motions of allocating an argument
4264 block even if the size is zero because we may be storing args
4265 in the area reserved for register arguments, which may be part of
4268 poly_int64 needed
= adjusted_args_size
.constant
;
4270 /* Store the maximum argument space used. It will be pushed by
4271 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
4274 crtl
->outgoing_args_size
= upper_bound (crtl
->outgoing_args_size
,
4277 if (must_preallocate
)
4279 if (ACCUMULATE_OUTGOING_ARGS
)
4281 /* Since the stack pointer will never be pushed, it is
4282 possible for the evaluation of a parm to clobber
4283 something we have already written to the stack.
4284 Since most function calls on RISC machines do not use
4285 the stack, this is uncommon, but must work correctly.
4287 Therefore, we save any area of the stack that was already
4288 written and that we are using. Here we set up to do this
4289 by making a new stack usage map from the old one. The
4290 actual save will be done by store_one_arg.
4292 Another approach might be to try to reorder the argument
4293 evaluations to avoid this conflicting stack usage. */
4295 /* Since we will be writing into the entire argument area,
4296 the map must be allocated for its entire size, not just
4297 the part that is the responsibility of the caller. */
4298 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
4299 needed
+= reg_parm_stack_space
;
4301 poly_int64 limit
= needed
;
4302 if (ARGS_GROW_DOWNWARD
)
4305 /* For polynomial sizes, this is the maximum possible
4306 size needed for arguments with a constant size
4308 HOST_WIDE_INT const_limit
= constant_lower_bound (limit
);
4309 highest_outgoing_arg_in_use
4310 = MAX (initial_highest_arg_in_use
, const_limit
);
4312 free (stack_usage_map_buf
);
4313 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
4314 stack_usage_map
= stack_usage_map_buf
;
4316 if (initial_highest_arg_in_use
)
4317 memcpy (stack_usage_map
, initial_stack_usage_map
,
4318 initial_highest_arg_in_use
);
4320 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
4321 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
4322 (highest_outgoing_arg_in_use
4323 - initial_highest_arg_in_use
));
4326 /* The address of the outgoing argument list must not be
4327 copied to a register here, because argblock would be left
4328 pointing to the wrong place after the call to
4329 allocate_dynamic_stack_space below. */
4331 argblock
= virtual_outgoing_args_rtx
;
4335 /* Try to reuse some or all of the pending_stack_adjust
4336 to get this space. */
4337 if (inhibit_defer_pop
== 0
4338 && (combine_pending_stack_adjustment_and_call
4340 unadjusted_args_size
,
4341 &adjusted_args_size
,
4342 preferred_unit_stack_boundary
)))
4344 /* combine_pending_stack_adjustment_and_call computes
4345 an adjustment before the arguments are allocated.
4346 Account for them and see whether or not the stack
4347 needs to go up or down. */
4348 needed
= unadjusted_args_size
- needed
;
4351 combine_pending_stack_adjustment_and_call. */
4352 gcc_checking_assert (ordered_p (needed
, 0));
4353 if (maybe_lt (needed
, 0))
4355 /* We're releasing stack space. */
4356 /* ??? We can avoid any adjustment at all if we're
4357 already aligned. FIXME. */
4358 pending_stack_adjust
= -needed
;
4359 do_pending_stack_adjust ();
4363 /* We need to allocate space. We'll do that in
4364 push_block below. */
4365 pending_stack_adjust
= 0;
4368 /* Special case this because overhead of `push_block' in
4369 this case is non-trivial. */
4370 if (known_eq (needed
, 0))
4371 argblock
= virtual_outgoing_args_rtx
;
4374 rtx needed_rtx
= gen_int_mode (needed
, Pmode
);
4375 argblock
= push_block (needed_rtx
, 0, 0);
4376 if (ARGS_GROW_DOWNWARD
)
4377 argblock
= plus_constant (Pmode
, argblock
, needed
);
4380 /* We only really need to call `copy_to_reg' in the case
4381 where push insns are going to be used to pass ARGBLOCK
4382 to a function call in ARGS. In that case, the stack
4383 pointer changes value from the allocation point to the
4384 call point, and hence the value of
4385 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
4386 as well always do it. */
4387 argblock
= copy_to_reg (argblock
);
4392 if (ACCUMULATE_OUTGOING_ARGS
)
4394 /* The save/restore code in store_one_arg handles all
4395 cases except one: a constructor call (including a C
4396 function returning a BLKmode struct) to initialize
4398 if (stack_arg_under_construction
)
4402 (adjusted_args_size
.constant
4403 + (OUTGOING_REG_PARM_STACK_SPACE (!fndecl
? fntype
4404 : TREE_TYPE (fndecl
))
4405 ? 0 : reg_parm_stack_space
), Pmode
));
4406 if (old_stack_level
== 0)
4408 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
4409 old_stack_pointer_delta
= stack_pointer_delta
;
4410 old_pending_adj
= pending_stack_adjust
;
4411 pending_stack_adjust
= 0;
4412 /* stack_arg_under_construction says whether a stack
4413 arg is being constructed at the old stack level.
4414 Pushing the stack gets a clean outgoing argument
4416 old_stack_arg_under_construction
4417 = stack_arg_under_construction
;
4418 stack_arg_under_construction
= 0;
4419 /* Make a new map for the new argument list. */
4420 free (stack_usage_map_buf
);
4421 stack_usage_map_buf
= XCNEWVEC (char, highest_outgoing_arg_in_use
);
4422 stack_usage_map
= stack_usage_map_buf
;
4423 highest_outgoing_arg_in_use
= 0;
4424 stack_usage_watermark
= HOST_WIDE_INT_M1U
;
4426 /* We can pass TRUE as the 4th argument because we just
4427 saved the stack pointer and will restore it right after
4429 allocate_dynamic_stack_space (push_size
, 0, BIGGEST_ALIGNMENT
,
4433 /* If argument evaluation might modify the stack pointer,
4434 copy the address of the argument list to a register. */
4435 for (i
= 0; i
< num_actuals
; i
++)
4436 if (args
[i
].pass_on_stack
)
4438 argblock
= copy_addr_to_reg (argblock
);
4443 compute_argument_addresses (args
, argblock
, num_actuals
);
4445 /* Stack is properly aligned, pops can't safely be deferred during
4446 the evaluation of the arguments. */
4449 /* Precompute all register parameters. It isn't safe to compute
4450 anything once we have started filling any specific hard regs.
4451 TLS symbols sometimes need a call to resolve. Precompute
4452 register parameters before any stack pointer manipulation
4453 to avoid unaligned stack in the called function. */
4454 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
4458 /* Perform stack alignment before the first push (the last arg). */
4460 && maybe_gt (adjusted_args_size
.constant
, reg_parm_stack_space
)
4461 && maybe_ne (adjusted_args_size
.constant
, unadjusted_args_size
))
4463 /* When the stack adjustment is pending, we get better code
4464 by combining the adjustments. */
4465 if (maybe_ne (pending_stack_adjust
, 0)
4466 && ! inhibit_defer_pop
4467 && (combine_pending_stack_adjustment_and_call
4468 (&pending_stack_adjust
,
4469 unadjusted_args_size
,
4470 &adjusted_args_size
,
4471 preferred_unit_stack_boundary
)))
4472 do_pending_stack_adjust ();
4473 else if (argblock
== 0)
4474 anti_adjust_stack (gen_int_mode (adjusted_args_size
.constant
4475 - unadjusted_args_size
,
4478 /* Now that the stack is properly aligned, pops can't safely
4479 be deferred during the evaluation of the arguments. */
4482 /* Record the maximum pushed stack space size. We need to delay
4483 doing it this far to take into account the optimization done
4484 by combine_pending_stack_adjustment_and_call. */
4485 if (flag_stack_usage_info
4486 && !ACCUMULATE_OUTGOING_ARGS
4488 && adjusted_args_size
.var
== 0)
4490 poly_int64 pushed
= (adjusted_args_size
.constant
4491 + pending_stack_adjust
);
4492 current_function_pushed_stack_size
4493 = upper_bound (current_function_pushed_stack_size
, pushed
);
4496 funexp
= rtx_for_function_call (fndecl
, addr
);
4498 if (CALL_EXPR_STATIC_CHAIN (exp
))
4499 static_chain_value
= expand_normal (CALL_EXPR_STATIC_CHAIN (exp
));
4501 static_chain_value
= 0;
4503 #ifdef REG_PARM_STACK_SPACE
4504 /* Save the fixed argument area if it's part of the caller's frame and
4505 is clobbered by argument setup for this call. */
4506 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
4507 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
4508 &low_to_save
, &high_to_save
);
4511 /* Now store (and compute if necessary) all non-register parms.
4512 These come before register parms, since they can require block-moves,
4513 which could clobber the registers used for register parms.
4514 Parms which have partial registers are not stored here,
4515 but we do preallocate space here if they want that. */
4517 for (i
= 0; i
< num_actuals
; i
++)
4519 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
4521 rtx_insn
*before_arg
= get_last_insn ();
4523 /* We don't allow passing huge (> 2^30 B) arguments
4524 by value. It would cause an overflow later on. */
4525 if (constant_lower_bound (adjusted_args_size
.constant
)
4526 >= (1 << (HOST_BITS_PER_INT
- 2)))
4528 sorry ("passing too large argument on stack");
4532 if (store_one_arg (&args
[i
], argblock
, flags
,
4533 adjusted_args_size
.var
!= 0,
4534 reg_parm_stack_space
)
4536 && check_sibcall_argument_overlap (before_arg
,
4538 sibcall_failure
= 1;
4543 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
4544 gen_rtx_USE (VOIDmode
, args
[i
].stack
),
4548 /* If we have a parm that is passed in registers but not in memory
4549 and whose alignment does not permit a direct copy into registers,
4550 make a group of pseudos that correspond to each register that we
4552 if (STRICT_ALIGNMENT
)
4553 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
4555 /* Now store any partially-in-registers parm.
4556 This is the last place a block-move can happen. */
4558 for (i
= 0; i
< num_actuals
; i
++)
4559 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
4561 rtx_insn
*before_arg
= get_last_insn ();
4563 /* On targets with weird calling conventions (e.g. PA) it's
4564 hard to ensure that all cases of argument overlap between
4565 stack and registers work. Play it safe and bail out. */
4566 if (ARGS_GROW_DOWNWARD
&& !STACK_GROWS_DOWNWARD
)
4568 sibcall_failure
= 1;
4572 if (store_one_arg (&args
[i
], argblock
, flags
,
4573 adjusted_args_size
.var
!= 0,
4574 reg_parm_stack_space
)
4576 && check_sibcall_argument_overlap (before_arg
,
4578 sibcall_failure
= 1;
4581 bool any_regs
= false;
4582 for (i
= 0; i
< num_actuals
; i
++)
4583 if (args
[i
].reg
!= NULL_RTX
)
4586 targetm
.calls
.call_args (args
[i
].reg
, funtype
);
4589 targetm
.calls
.call_args (pc_rtx
, funtype
);
4591 /* Figure out the register where the value, if any, will come back. */
4593 if (TYPE_MODE (rettype
) != VOIDmode
4594 && ! structure_value_addr
)
4596 if (pcc_struct_value
)
4597 valreg
= hard_function_value (build_pointer_type (rettype
),
4598 fndecl
, NULL
, (pass
== 0));
4600 valreg
= hard_function_value (rettype
, fndecl
, fntype
,
4603 /* If VALREG is a PARALLEL whose first member has a zero
4604 offset, use that. This is for targets such as m68k that
4605 return the same value in multiple places. */
4606 if (GET_CODE (valreg
) == PARALLEL
)
4608 rtx elem
= XVECEXP (valreg
, 0, 0);
4609 rtx where
= XEXP (elem
, 0);
4610 rtx offset
= XEXP (elem
, 1);
4611 if (offset
== const0_rtx
4612 && GET_MODE (where
) == GET_MODE (valreg
))
4617 /* If register arguments require space on the stack and stack space
4618 was not preallocated, allocate stack space here for arguments
4619 passed in registers. */
4620 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
4621 && !ACCUMULATE_OUTGOING_ARGS
4622 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
4623 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
4625 /* Pass the function the address in which to return a
4627 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
4629 structure_value_addr
4630 = convert_memory_address (Pmode
, structure_value_addr
);
4631 emit_move_insn (struct_value
,
4633 force_operand (structure_value_addr
,
4636 if (REG_P (struct_value
))
4637 use_reg (&call_fusage
, struct_value
);
4640 after_args
= get_last_insn ();
4641 funexp
= prepare_call_address (fndecl
? fndecl
: fntype
, funexp
,
4642 static_chain_value
, &call_fusage
,
4643 reg_parm_seen
, flags
);
4645 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
4646 pass
== 0, &sibcall_failure
);
4648 /* Save a pointer to the last insn before the call, so that we can
4649 later safely search backwards to find the CALL_INSN. */
4650 before_call
= get_last_insn ();
4652 /* Set up next argument register. For sibling calls on machines
4653 with register windows this should be the incoming register. */
4655 next_arg_reg
= targetm
.calls
.function_incoming_arg
4656 (args_so_far
, function_arg_info::end_marker ());
4658 next_arg_reg
= targetm
.calls
.function_arg
4659 (args_so_far
, function_arg_info::end_marker ());
4661 if (pass
== 1 && (return_flags
& ERF_RETURNS_ARG
))
4663 int arg_nr
= return_flags
& ERF_RETURN_ARG_MASK
;
4664 arg_nr
= num_actuals
- arg_nr
- 1;
4666 && arg_nr
< num_actuals
4670 && GET_MODE (args
[arg_nr
].reg
) == GET_MODE (valreg
))
4672 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args
[arg_nr
].tree_value
)),
4673 gen_rtx_SET (valreg
, args
[arg_nr
].reg
),
4676 /* All arguments and registers used for the call must be set up by
4679 /* Stack must be properly aligned now. */
4681 || multiple_p (stack_pointer_delta
,
4682 preferred_unit_stack_boundary
));
4684 /* Generate the actual call instruction. */
4685 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
4686 adjusted_args_size
.constant
, struct_value_size
,
4687 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
4688 flags
, args_so_far
);
4692 rtx_call_insn
*last
;
4693 rtx datum
= NULL_RTX
;
4694 if (fndecl
!= NULL_TREE
)
4696 datum
= XEXP (DECL_RTL (fndecl
), 0);
4697 gcc_assert (datum
!= NULL_RTX
4698 && GET_CODE (datum
) == SYMBOL_REF
);
4700 last
= last_call_insn ();
4701 add_reg_note (last
, REG_CALL_DECL
, datum
);
4704 /* If the call setup or the call itself overlaps with anything
4705 of the argument setup we probably clobbered our call address.
4706 In that case we can't do sibcalls. */
4708 && check_sibcall_argument_overlap (after_args
, 0, 0))
4709 sibcall_failure
= 1;
4711 /* If a non-BLKmode value is returned at the most significant end
4712 of a register, shift the register right by the appropriate amount
4713 and update VALREG accordingly. BLKmode values are handled by the
4714 group load/store machinery below. */
4715 if (!structure_value_addr
4716 && !pcc_struct_value
4717 && TYPE_MODE (rettype
) != VOIDmode
4718 && TYPE_MODE (rettype
) != BLKmode
4720 && targetm
.calls
.return_in_msb (rettype
))
4722 if (shift_return_value (TYPE_MODE (rettype
), false, valreg
))
4723 sibcall_failure
= 1;
4724 valreg
= gen_rtx_REG (TYPE_MODE (rettype
), REGNO (valreg
));
4727 if (pass
&& (flags
& ECF_MALLOC
))
4729 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
4730 rtx_insn
*last
, *insns
;
4732 /* The return value from a malloc-like function is a pointer. */
4733 if (TREE_CODE (rettype
) == POINTER_TYPE
)
4734 mark_reg_pointer (temp
, MALLOC_ABI_ALIGNMENT
);
4736 emit_move_insn (temp
, valreg
);
4738 /* The return value from a malloc-like function cannot alias
4740 last
= get_last_insn ();
4741 add_reg_note (last
, REG_NOALIAS
, temp
);
4743 /* Write out the sequence. */
4744 insns
= get_insns ();
4750 /* For calls to `setjmp', etc., inform
4751 function.c:setjmp_warnings that it should complain if
4752 nonvolatile values are live. For functions that cannot
4753 return, inform flow that control does not fall through. */
4755 if ((flags
& ECF_NORETURN
) || pass
== 0)
4757 /* The barrier must be emitted
4758 immediately after the CALL_INSN. Some ports emit more
4759 than just a CALL_INSN above, so we must search for it here. */
4761 rtx_insn
*last
= get_last_insn ();
4762 while (!CALL_P (last
))
4764 last
= PREV_INSN (last
);
4765 /* There was no CALL_INSN? */
4766 gcc_assert (last
!= before_call
);
4769 emit_barrier_after (last
);
4771 /* Stack adjustments after a noreturn call are dead code.
4772 However when NO_DEFER_POP is in effect, we must preserve
4773 stack_pointer_delta. */
4774 if (inhibit_defer_pop
== 0)
4776 stack_pointer_delta
= old_stack_allocated
;
4777 pending_stack_adjust
= 0;
4781 /* If value type not void, return an rtx for the value. */
4783 if (TYPE_MODE (rettype
) == VOIDmode
4785 target
= const0_rtx
;
4786 else if (structure_value_addr
)
4788 if (target
== 0 || !MEM_P (target
))
4791 = gen_rtx_MEM (TYPE_MODE (rettype
),
4792 memory_address (TYPE_MODE (rettype
),
4793 structure_value_addr
));
4794 set_mem_attributes (target
, rettype
, 1);
4797 else if (pcc_struct_value
)
4799 /* This is the special C++ case where we need to
4800 know what the true target was. We take care to
4801 never use this value more than once in one expression. */
4802 target
= gen_rtx_MEM (TYPE_MODE (rettype
),
4803 copy_to_reg (valreg
));
4804 set_mem_attributes (target
, rettype
, 1);
4806 /* Handle calls that return values in multiple non-contiguous locations.
4807 The Irix 6 ABI has examples of this. */
4808 else if (GET_CODE (valreg
) == PARALLEL
)
4811 target
= emit_group_move_into_temps (valreg
);
4812 else if (rtx_equal_p (target
, valreg
))
4814 else if (GET_CODE (target
) == PARALLEL
)
4815 /* Handle the result of a emit_group_move_into_temps
4816 call in the previous pass. */
4817 emit_group_move (target
, valreg
);
4819 emit_group_store (target
, valreg
, rettype
,
4820 int_size_in_bytes (rettype
));
4823 && GET_MODE (target
) == TYPE_MODE (rettype
)
4824 && GET_MODE (target
) == GET_MODE (valreg
))
4826 bool may_overlap
= false;
4828 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
4829 reg to a plain register. */
4830 if (!REG_P (target
) || HARD_REGISTER_P (target
))
4831 valreg
= avoid_likely_spilled_reg (valreg
);
4833 /* If TARGET is a MEM in the argument area, and we have
4834 saved part of the argument area, then we can't store
4835 directly into TARGET as it may get overwritten when we
4836 restore the argument save area below. Don't work too
4837 hard though and simply force TARGET to a register if it
4838 is a MEM; the optimizer is quite likely to sort it out. */
4839 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
4840 for (i
= 0; i
< num_actuals
; i
++)
4841 if (args
[i
].save_area
)
4848 target
= copy_to_reg (valreg
);
4851 /* TARGET and VALREG cannot be equal at this point
4852 because the latter would not have
4853 REG_FUNCTION_VALUE_P true, while the former would if
4854 it were referring to the same register.
4856 If they refer to the same register, this move will be
4857 a no-op, except when function inlining is being
4859 emit_move_insn (target
, valreg
);
4861 /* If we are setting a MEM, this code must be executed.
4862 Since it is emitted after the call insn, sibcall
4863 optimization cannot be performed in that case. */
4865 sibcall_failure
= 1;
4869 target
= copy_to_reg (avoid_likely_spilled_reg (valreg
));
4871 /* If we promoted this return value, make the proper SUBREG.
4872 TARGET might be const0_rtx here, so be careful. */
4874 && TYPE_MODE (rettype
) != BLKmode
4875 && GET_MODE (target
) != TYPE_MODE (rettype
))
4877 tree type
= rettype
;
4878 int unsignedp
= TYPE_UNSIGNED (type
);
4881 /* Ensure we promote as expected, and get the new unsignedness. */
4882 pmode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
4884 gcc_assert (GET_MODE (target
) == pmode
);
4886 poly_uint64 offset
= subreg_lowpart_offset (TYPE_MODE (type
),
4888 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
4889 SUBREG_PROMOTED_VAR_P (target
) = 1;
4890 SUBREG_PROMOTED_SET (target
, unsignedp
);
4893 /* If size of args is variable or this was a constructor call for a stack
4894 argument, restore saved stack-pointer value. */
4896 if (old_stack_level
)
4898 rtx_insn
*prev
= get_last_insn ();
4900 emit_stack_restore (SAVE_BLOCK
, old_stack_level
);
4901 stack_pointer_delta
= old_stack_pointer_delta
;
4903 fixup_args_size_notes (prev
, get_last_insn (), stack_pointer_delta
);
4905 pending_stack_adjust
= old_pending_adj
;
4906 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
4907 stack_arg_under_construction
= old_stack_arg_under_construction
;
4908 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4909 stack_usage_map
= initial_stack_usage_map
;
4910 stack_usage_watermark
= initial_stack_usage_watermark
;
4911 sibcall_failure
= 1;
4913 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
4915 #ifdef REG_PARM_STACK_SPACE
4917 restore_fixed_argument_area (save_area
, argblock
,
4918 high_to_save
, low_to_save
);
4921 /* If we saved any argument areas, restore them. */
4922 for (i
= 0; i
< num_actuals
; i
++)
4923 if (args
[i
].save_area
)
4925 machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
4927 = gen_rtx_MEM (save_mode
,
4928 memory_address (save_mode
,
4929 XEXP (args
[i
].stack_slot
, 0)));
4931 if (save_mode
!= BLKmode
)
4932 emit_move_insn (stack_area
, args
[i
].save_area
);
4934 emit_block_move (stack_area
, args
[i
].save_area
,
4936 (args
[i
].locate
.size
.constant
, Pmode
)),
4937 BLOCK_OP_CALL_PARM
);
4940 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4941 stack_usage_map
= initial_stack_usage_map
;
4942 stack_usage_watermark
= initial_stack_usage_watermark
;
4945 /* If this was alloca, record the new stack level. */
4946 if (flags
& ECF_MAY_BE_ALLOCA
)
4947 record_new_stack_level ();
4949 /* Free up storage we no longer need. */
4950 for (i
= 0; i
< num_actuals
; ++i
)
4951 free (args
[i
].aligned_regs
);
4953 targetm
.calls
.end_call_args ();
4955 insns
= get_insns ();
4960 tail_call_insns
= insns
;
4962 /* Restore the pending stack adjustment now that we have
4963 finished generating the sibling call sequence. */
4965 restore_pending_stack_adjust (&save
);
4967 /* Prepare arg structure for next iteration. */
4968 for (i
= 0; i
< num_actuals
; i
++)
4971 args
[i
].aligned_regs
= 0;
4975 sbitmap_free (stored_args_map
);
4976 internal_arg_pointer_exp_state
.scan_start
= NULL
;
4977 internal_arg_pointer_exp_state
.cache
.release ();
4981 normal_call_insns
= insns
;
4983 /* Verify that we've deallocated all the stack we used. */
4984 gcc_assert ((flags
& ECF_NORETURN
)
4985 || known_eq (old_stack_allocated
,
4987 - pending_stack_adjust
));
4990 /* If something prevents making this a sibling call,
4991 zero out the sequence. */
4992 if (sibcall_failure
)
4993 tail_call_insns
= NULL
;
4998 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
4999 arguments too, as argument area is now clobbered by the call. */
5000 if (tail_call_insns
)
5002 emit_insn (tail_call_insns
);
5003 crtl
->tail_call_emit
= true;
5007 emit_insn (normal_call_insns
);
5009 /* Ideally we'd emit a message for all of the ways that it could
5011 maybe_complain_about_tail_call (exp
, "tail call production failed");
5014 currently_expanding_call
--;
5016 free (stack_usage_map_buf
);
5021 /* A sibling call sequence invalidates any REG_EQUIV notes made for
5022 this function's incoming arguments.
5024 At the start of RTL generation we know the only REG_EQUIV notes
5025 in the rtl chain are those for incoming arguments, so we can look
5026 for REG_EQUIV notes between the start of the function and the
5027 NOTE_INSN_FUNCTION_BEG.
5029 This is (slight) overkill. We could keep track of the highest
5030 argument we clobber and be more selective in removing notes, but it
5031 does not seem to be worth the effort. */
5034 fixup_tail_calls (void)
5038 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5042 /* There are never REG_EQUIV notes for the incoming arguments
5043 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
5045 && NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
)
5048 note
= find_reg_note (insn
, REG_EQUIV
, 0);
5050 remove_note (insn
, note
);
5051 note
= find_reg_note (insn
, REG_EQUIV
, 0);
5056 /* Traverse a list of TYPES and expand all complex types into their
5059 split_complex_types (tree types
)
5063 /* Before allocating memory, check for the common case of no complex. */
5064 for (p
= types
; p
; p
= TREE_CHAIN (p
))
5066 tree type
= TREE_VALUE (p
);
5067 if (TREE_CODE (type
) == COMPLEX_TYPE
5068 && targetm
.calls
.split_complex_arg (type
))
5074 types
= copy_list (types
);
5076 for (p
= types
; p
; p
= TREE_CHAIN (p
))
5078 tree complex_type
= TREE_VALUE (p
);
5080 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
5081 && targetm
.calls
.split_complex_arg (complex_type
))
5085 /* Rewrite complex type with component type. */
5086 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
5087 next
= TREE_CHAIN (p
);
5089 /* Add another component type for the imaginary part. */
5090 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
5091 TREE_CHAIN (p
) = imag
;
5092 TREE_CHAIN (imag
) = next
;
5094 /* Skip the newly created node. */
5102 /* Output a library call to function ORGFUN (a SYMBOL_REF rtx)
5103 for a value of mode OUTMODE,
5104 with NARGS different arguments, passed as ARGS.
5105 Store the return value if RETVAL is nonzero: store it in VALUE if
5106 VALUE is nonnull, otherwise pick a convenient location. In either
5107 case return the location of the stored value.
5109 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
5110 `const' calls, LCT_PURE for `pure' calls, or another LCT_ value for
5111 other types of library calls. */
5114 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
5115 enum libcall_type fn_type
,
5116 machine_mode outmode
, int nargs
, rtx_mode_t
*args
)
5118 /* Total size in bytes of all the stack-parms scanned so far. */
5119 struct args_size args_size
;
5120 /* Size of arguments before any adjustments (such as rounding). */
5121 struct args_size original_args_size
;
5124 /* Todo, choose the correct decl type of orgfun. Sadly this information
5125 isn't present here, so we default to native calling abi here. */
5126 tree fndecl ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
5127 tree fntype ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
5130 CUMULATIVE_ARGS args_so_far_v
;
5131 cumulative_args_t args_so_far
;
5138 struct locate_and_pad_arg_data locate
;
5142 int old_inhibit_defer_pop
= inhibit_defer_pop
;
5143 rtx call_fusage
= 0;
5146 int pcc_struct_value
= 0;
5147 poly_int64 struct_value_size
= 0;
5149 int reg_parm_stack_space
= 0;
5151 rtx_insn
*before_call
;
5152 bool have_push_fusage
;
5153 tree tfom
; /* type_for_mode (outmode, 0) */
5155 #ifdef REG_PARM_STACK_SPACE
5156 /* Define the boundary of the register parm stack space that needs to be
5158 int low_to_save
= 0, high_to_save
= 0;
5159 rtx save_area
= 0; /* Place that it is saved. */
5162 /* Size of the stack reserved for parameter registers. */
5163 unsigned int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
5164 char *initial_stack_usage_map
= stack_usage_map
;
5165 unsigned HOST_WIDE_INT initial_stack_usage_watermark
= stack_usage_watermark
;
5166 char *stack_usage_map_buf
= NULL
;
5168 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
5170 #ifdef REG_PARM_STACK_SPACE
5171 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
5174 /* By default, library functions cannot throw. */
5175 flags
= ECF_NOTHROW
;
5188 flags
|= ECF_NORETURN
;
5191 flags
&= ~ECF_NOTHROW
;
5193 case LCT_RETURNS_TWICE
:
5194 flags
= ECF_RETURNS_TWICE
;
5199 /* Ensure current function's preferred stack boundary is at least
5201 if (crtl
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
5202 crtl
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
5204 /* If this kind of value comes back in memory,
5205 decide where in memory it should come back. */
5206 if (outmode
!= VOIDmode
)
5208 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
5209 if (aggregate_value_p (tfom
, 0))
5211 #ifdef PCC_STATIC_STRUCT_RETURN
5213 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
5214 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
5215 pcc_struct_value
= 1;
5217 value
= gen_reg_rtx (outmode
);
5218 #else /* not PCC_STATIC_STRUCT_RETURN */
5219 struct_value_size
= GET_MODE_SIZE (outmode
);
5220 if (value
!= 0 && MEM_P (value
))
5223 mem_value
= assign_temp (tfom
, 1, 1);
5225 /* This call returns a big structure. */
5226 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
5230 tfom
= void_type_node
;
5232 /* ??? Unfinished: must pass the memory address as an argument. */
5234 /* Copy all the libcall-arguments out of the varargs data
5235 and into a vector ARGVEC.
5237 Compute how to pass each argument. We only support a very small subset
5238 of the full argument passing conventions to limit complexity here since
5239 library functions shouldn't have many args. */
5241 argvec
= XALLOCAVEC (struct arg
, nargs
+ 1);
5242 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
5244 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
5245 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v
, outmode
, fun
);
5247 INIT_CUMULATIVE_ARGS (args_so_far_v
, NULL_TREE
, fun
, 0, nargs
);
5249 args_so_far
= pack_cumulative_args (&args_so_far_v
);
5251 args_size
.constant
= 0;
5258 /* If there's a structure value address to be passed,
5259 either pass it in the special place, or pass it as an extra argument. */
5260 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
5262 rtx addr
= XEXP (mem_value
, 0);
5266 /* Make sure it is a reasonable operand for a move or push insn. */
5267 if (!REG_P (addr
) && !MEM_P (addr
)
5268 && !(CONSTANT_P (addr
)
5269 && targetm
.legitimate_constant_p (Pmode
, addr
)))
5270 addr
= force_operand (addr
, NULL_RTX
);
5272 argvec
[count
].value
= addr
;
5273 argvec
[count
].mode
= Pmode
;
5274 argvec
[count
].partial
= 0;
5276 function_arg_info
ptr_arg (Pmode
, /*named=*/true);
5277 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
, ptr_arg
);
5278 gcc_assert (targetm
.calls
.arg_partial_bytes (args_so_far
, ptr_arg
) == 0);
5280 locate_and_pad_parm (Pmode
, NULL_TREE
,
5281 #ifdef STACK_PARMS_IN_REG_PARM_AREA
5284 argvec
[count
].reg
!= 0,
5286 reg_parm_stack_space
, 0,
5287 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
5289 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
5290 || reg_parm_stack_space
> 0)
5291 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
5293 targetm
.calls
.function_arg_advance (args_so_far
, ptr_arg
);
5298 for (unsigned int i
= 0; count
< nargs
; i
++, count
++)
5300 rtx val
= args
[i
].first
;
5301 function_arg_info
arg (args
[i
].second
, /*named=*/true);
5304 /* We cannot convert the arg value to the mode the library wants here;
5305 must do it earlier where we know the signedness of the arg. */
5306 gcc_assert (arg
.mode
!= BLKmode
5307 && (GET_MODE (val
) == arg
.mode
5308 || GET_MODE (val
) == VOIDmode
));
5310 /* Make sure it is a reasonable operand for a move or push insn. */
5311 if (!REG_P (val
) && !MEM_P (val
)
5312 && !(CONSTANT_P (val
)
5313 && targetm
.legitimate_constant_p (arg
.mode
, val
)))
5314 val
= force_operand (val
, NULL_RTX
);
5316 if (pass_by_reference (&args_so_far_v
, arg
))
5319 int must_copy
= !reference_callee_copied (&args_so_far_v
, arg
);
5321 /* If this was a CONST function, it is now PURE since it now
5323 if (flags
& ECF_CONST
)
5325 flags
&= ~ECF_CONST
;
5329 if (MEM_P (val
) && !must_copy
)
5331 tree val_expr
= MEM_EXPR (val
);
5333 mark_addressable (val_expr
);
5338 slot
= assign_temp (lang_hooks
.types
.type_for_mode (arg
.mode
, 0),
5340 emit_move_insn (slot
, val
);
5343 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
5344 gen_rtx_USE (VOIDmode
, slot
),
5347 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
5348 gen_rtx_CLOBBER (VOIDmode
,
5353 arg
.pass_by_reference
= true;
5354 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
5357 arg
.mode
= promote_function_mode (NULL_TREE
, arg
.mode
, &unsigned_p
,
5359 argvec
[count
].mode
= arg
.mode
;
5360 argvec
[count
].value
= convert_modes (arg
.mode
, GET_MODE (val
), val
,
5362 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
, arg
);
5364 argvec
[count
].partial
5365 = targetm
.calls
.arg_partial_bytes (args_so_far
, arg
);
5367 if (argvec
[count
].reg
== 0
5368 || argvec
[count
].partial
!= 0
5369 || reg_parm_stack_space
> 0)
5371 locate_and_pad_parm (arg
.mode
, NULL_TREE
,
5372 #ifdef STACK_PARMS_IN_REG_PARM_AREA
5375 argvec
[count
].reg
!= 0,
5377 reg_parm_stack_space
, argvec
[count
].partial
,
5378 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
5379 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
5380 gcc_assert (!argvec
[count
].locate
.size
.var
);
5382 #ifdef BLOCK_REG_PADDING
5384 /* The argument is passed entirely in registers. See at which
5385 end it should be padded. */
5386 argvec
[count
].locate
.where_pad
=
5387 BLOCK_REG_PADDING (arg
.mode
, NULL_TREE
,
5388 known_le (GET_MODE_SIZE (arg
.mode
),
5392 targetm
.calls
.function_arg_advance (args_so_far
, arg
);
5395 for (int i
= 0; i
< nargs
; i
++)
5396 if (reg_parm_stack_space
> 0
5397 || argvec
[i
].reg
== 0
5398 || argvec
[i
].partial
!= 0)
5399 update_stack_alignment_for_call (&argvec
[i
].locate
);
5401 /* If this machine requires an external definition for library
5402 functions, write one out. */
5403 assemble_external_libcall (fun
);
5405 original_args_size
= args_size
;
5406 args_size
.constant
= (aligned_upper_bound (args_size
.constant
5407 + stack_pointer_delta
,
5409 - stack_pointer_delta
);
5411 args_size
.constant
= upper_bound (args_size
.constant
,
5412 reg_parm_stack_space
);
5414 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
5415 args_size
.constant
-= reg_parm_stack_space
;
5417 crtl
->outgoing_args_size
= upper_bound (crtl
->outgoing_args_size
,
5418 args_size
.constant
);
5420 if (flag_stack_usage_info
&& !ACCUMULATE_OUTGOING_ARGS
)
5422 poly_int64 pushed
= args_size
.constant
+ pending_stack_adjust
;
5423 current_function_pushed_stack_size
5424 = upper_bound (current_function_pushed_stack_size
, pushed
);
5427 if (ACCUMULATE_OUTGOING_ARGS
)
5429 /* Since the stack pointer will never be pushed, it is possible for
5430 the evaluation of a parm to clobber something we have already
5431 written to the stack. Since most function calls on RISC machines
5432 do not use the stack, this is uncommon, but must work correctly.
5434 Therefore, we save any area of the stack that was already written
5435 and that we are using. Here we set up to do this by making a new
5436 stack usage map from the old one.
5438 Another approach might be to try to reorder the argument
5439 evaluations to avoid this conflicting stack usage. */
5441 needed
= args_size
.constant
;
5443 /* Since we will be writing into the entire argument area, the
5444 map must be allocated for its entire size, not just the part that
5445 is the responsibility of the caller. */
5446 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
5447 needed
+= reg_parm_stack_space
;
5449 poly_int64 limit
= needed
;
5450 if (ARGS_GROW_DOWNWARD
)
5453 /* For polynomial sizes, this is the maximum possible size needed
5454 for arguments with a constant size and offset. */
5455 HOST_WIDE_INT const_limit
= constant_lower_bound (limit
);
5456 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
5459 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
5460 stack_usage_map
= stack_usage_map_buf
;
5462 if (initial_highest_arg_in_use
)
5463 memcpy (stack_usage_map
, initial_stack_usage_map
,
5464 initial_highest_arg_in_use
);
5466 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
5467 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
5468 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
5471 /* We must be careful to use virtual regs before they're instantiated,
5472 and real regs afterwards. Loop optimization, for example, can create
5473 new libcalls after we've instantiated the virtual regs, and if we
5474 use virtuals anyway, they won't match the rtl patterns. */
5476 if (virtuals_instantiated
)
5477 argblock
= plus_constant (Pmode
, stack_pointer_rtx
,
5478 STACK_POINTER_OFFSET
);
5480 argblock
= virtual_outgoing_args_rtx
;
5484 if (!targetm
.calls
.push_argument (0))
5485 argblock
= push_block (gen_int_mode (args_size
.constant
, Pmode
), 0, 0);
5488 /* We push args individually in reverse order, perform stack alignment
5489 before the first push (the last arg). */
5491 anti_adjust_stack (gen_int_mode (args_size
.constant
5492 - original_args_size
.constant
,
5497 #ifdef REG_PARM_STACK_SPACE
5498 if (ACCUMULATE_OUTGOING_ARGS
)
5500 /* The argument list is the property of the called routine and it
5501 may clobber it. If the fixed area has been used for previous
5502 parameters, we must save and restore it. */
5503 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
5504 &low_to_save
, &high_to_save
);
5508 /* When expanding a normal call, args are stored in push order,
5509 which is the reverse of what we have here. */
5510 bool any_regs
= false;
5511 for (int i
= nargs
; i
-- > 0; )
5512 if (argvec
[i
].reg
!= NULL_RTX
)
5514 targetm
.calls
.call_args (argvec
[i
].reg
, NULL_TREE
);
5518 targetm
.calls
.call_args (pc_rtx
, NULL_TREE
);
5520 /* Push the args that need to be pushed. */
5522 have_push_fusage
= false;
5524 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5525 are to be pushed. */
5526 for (count
= 0; count
< nargs
; count
++, argnum
--)
5528 machine_mode mode
= argvec
[argnum
].mode
;
5529 rtx val
= argvec
[argnum
].value
;
5530 rtx reg
= argvec
[argnum
].reg
;
5531 int partial
= argvec
[argnum
].partial
;
5532 unsigned int parm_align
= argvec
[argnum
].locate
.boundary
;
5533 poly_int64 lower_bound
= 0, upper_bound
= 0;
5535 if (! (reg
!= 0 && partial
== 0))
5539 if (ACCUMULATE_OUTGOING_ARGS
)
5541 /* If this is being stored into a pre-allocated, fixed-size,
5542 stack area, save any previous data at that location. */
5544 if (ARGS_GROW_DOWNWARD
)
5546 /* stack_slot is negative, but we want to index stack_usage_map
5547 with positive values. */
5548 upper_bound
= -argvec
[argnum
].locate
.slot_offset
.constant
+ 1;
5549 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
5553 lower_bound
= argvec
[argnum
].locate
.slot_offset
.constant
;
5554 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
5557 if (stack_region_maybe_used_p (lower_bound
, upper_bound
,
5558 reg_parm_stack_space
))
5560 /* We need to make a save area. */
5562 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
5563 machine_mode save_mode
5564 = int_mode_for_size (size
, 1).else_blk ();
5566 = plus_constant (Pmode
, argblock
,
5567 argvec
[argnum
].locate
.offset
.constant
);
5569 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
5571 if (save_mode
== BLKmode
)
5573 argvec
[argnum
].save_area
5574 = assign_stack_temp (BLKmode
,
5575 argvec
[argnum
].locate
.size
.constant
5578 emit_block_move (validize_mem
5579 (copy_rtx (argvec
[argnum
].save_area
)),
5582 (argvec
[argnum
].locate
.size
.constant
,
5584 BLOCK_OP_CALL_PARM
);
5588 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
5590 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
5595 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, parm_align
,
5596 partial
, reg
, 0, argblock
,
5598 (argvec
[argnum
].locate
.offset
.constant
, Pmode
)),
5599 reg_parm_stack_space
,
5600 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
), false);
5602 /* Now mark the segment we just used. */
5603 if (ACCUMULATE_OUTGOING_ARGS
)
5604 mark_stack_region_used (lower_bound
, upper_bound
);
5608 /* Indicate argument access so that alias.c knows that these
5611 use
= plus_constant (Pmode
, argblock
,
5612 argvec
[argnum
].locate
.offset
.constant
);
5613 else if (have_push_fusage
)
5617 /* When arguments are pushed, trying to tell alias.c where
5618 exactly this argument is won't work, because the
5619 auto-increment causes confusion. So we merely indicate
5620 that we access something with a known mode somewhere on
5622 use
= gen_rtx_PLUS (Pmode
, stack_pointer_rtx
,
5623 gen_rtx_SCRATCH (Pmode
));
5624 have_push_fusage
= true;
5626 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
5627 use
= gen_rtx_USE (VOIDmode
, use
);
5628 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
5634 fun
= prepare_call_address (NULL
, fun
, NULL
, &call_fusage
, 0, 0);
5636 /* Now load any reg parms into their regs. */
5638 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5639 are to be pushed. */
5640 for (count
= 0; count
< nargs
; count
++, argnum
--)
5642 machine_mode mode
= argvec
[argnum
].mode
;
5643 rtx val
= argvec
[argnum
].value
;
5644 rtx reg
= argvec
[argnum
].reg
;
5645 int partial
= argvec
[argnum
].partial
;
5647 /* Handle calls that pass values in multiple non-contiguous
5648 locations. The PA64 has examples of this for library calls. */
5649 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
5650 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
5651 else if (reg
!= 0 && partial
== 0)
5653 emit_move_insn (reg
, val
);
5654 #ifdef BLOCK_REG_PADDING
5655 poly_int64 size
= GET_MODE_SIZE (argvec
[argnum
].mode
);
5657 /* Copied from load_register_parameters. */
5659 /* Handle case where we have a value that needs shifting
5660 up to the msb. eg. a QImode value and we're padding
5661 upward on a BYTES_BIG_ENDIAN machine. */
5662 if (known_lt (size
, UNITS_PER_WORD
)
5663 && (argvec
[argnum
].locate
.where_pad
5664 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
5667 poly_int64 shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
5669 /* Assigning REG here rather than a temp makes CALL_FUSAGE
5670 report the whole reg as used. Strictly speaking, the
5671 call only uses SIZE bytes at the msb end, but it doesn't
5672 seem worth generating rtl to say that. */
5673 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
5674 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
, shift
, reg
, 1);
5676 emit_move_insn (reg
, x
);
5684 /* Any regs containing parms remain in use through the call. */
5685 for (count
= 0; count
< nargs
; count
++)
5687 rtx reg
= argvec
[count
].reg
;
5688 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
5689 use_group_regs (&call_fusage
, reg
);
5692 int partial
= argvec
[count
].partial
;
5696 gcc_assert (partial
% UNITS_PER_WORD
== 0);
5697 nregs
= partial
/ UNITS_PER_WORD
;
5698 use_regs (&call_fusage
, REGNO (reg
), nregs
);
5701 use_reg (&call_fusage
, reg
);
5705 /* Pass the function the address in which to return a structure value. */
5706 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
5708 emit_move_insn (struct_value
,
5710 force_operand (XEXP (mem_value
, 0),
5712 if (REG_P (struct_value
))
5713 use_reg (&call_fusage
, struct_value
);
5716 /* Don't allow popping to be deferred, since then
5717 cse'ing of library calls could delete a call and leave the pop. */
5719 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
5720 ? hard_libcall_value (outmode
, orgfun
) : NULL_RTX
);
5722 /* Stack must be properly aligned now. */
5723 gcc_assert (multiple_p (stack_pointer_delta
,
5724 PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
));
5726 before_call
= get_last_insn ();
5728 if (flag_callgraph_info
)
5729 record_final_call (SYMBOL_REF_DECL (orgfun
), UNKNOWN_LOCATION
);
5731 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
5732 will set inhibit_defer_pop to that value. */
5733 /* The return type is needed to decide how many bytes the function pops.
5734 Signedness plays no role in that, so for simplicity, we pretend it's
5735 always signed. We also assume that the list of arguments passed has
5736 no impact, so we pretend it is unknown. */
5738 emit_call_1 (fun
, NULL
,
5739 get_identifier (XSTR (orgfun
, 0)),
5740 build_function_type (tfom
, NULL_TREE
),
5741 original_args_size
.constant
, args_size
.constant
,
5743 targetm
.calls
.function_arg (args_so_far
,
5744 function_arg_info::end_marker ()),
5746 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, args_so_far
);
5751 gcc_assert (GET_CODE (datum
) == SYMBOL_REF
);
5752 rtx_call_insn
*last
= last_call_insn ();
5753 add_reg_note (last
, REG_CALL_DECL
, datum
);
5756 /* Right-shift returned value if necessary. */
5757 if (!pcc_struct_value
5758 && TYPE_MODE (tfom
) != BLKmode
5759 && targetm
.calls
.return_in_msb (tfom
))
5761 shift_return_value (TYPE_MODE (tfom
), false, valreg
);
5762 valreg
= gen_rtx_REG (TYPE_MODE (tfom
), REGNO (valreg
));
5765 targetm
.calls
.end_call_args ();
5767 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
5768 that it should complain if nonvolatile values are live. For
5769 functions that cannot return, inform flow that control does not
5771 if (flags
& ECF_NORETURN
)
5773 /* The barrier note must be emitted
5774 immediately after the CALL_INSN. Some ports emit more than
5775 just a CALL_INSN above, so we must search for it here. */
5776 rtx_insn
*last
= get_last_insn ();
5777 while (!CALL_P (last
))
5779 last
= PREV_INSN (last
);
5780 /* There was no CALL_INSN? */
5781 gcc_assert (last
!= before_call
);
5784 emit_barrier_after (last
);
5787 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
5788 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
5789 if (flags
& ECF_NOTHROW
)
5791 rtx_insn
*last
= get_last_insn ();
5792 while (!CALL_P (last
))
5794 last
= PREV_INSN (last
);
5795 /* There was no CALL_INSN? */
5796 gcc_assert (last
!= before_call
);
5799 make_reg_eh_region_note_nothrow_nononlocal (last
);
5802 /* Now restore inhibit_defer_pop to its actual original value. */
5807 /* Copy the value to the right place. */
5808 if (outmode
!= VOIDmode
&& retval
)
5814 if (value
!= mem_value
)
5815 emit_move_insn (value
, mem_value
);
5817 else if (GET_CODE (valreg
) == PARALLEL
)
5820 value
= gen_reg_rtx (outmode
);
5821 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
5825 /* Convert to the proper mode if a promotion has been active. */
5826 if (GET_MODE (valreg
) != outmode
)
5828 int unsignedp
= TYPE_UNSIGNED (tfom
);
5830 gcc_assert (promote_function_mode (tfom
, outmode
, &unsignedp
,
5831 fndecl
? TREE_TYPE (fndecl
) : fntype
, 1)
5832 == GET_MODE (valreg
));
5833 valreg
= convert_modes (outmode
, GET_MODE (valreg
), valreg
, 0);
5837 emit_move_insn (value
, valreg
);
5843 if (ACCUMULATE_OUTGOING_ARGS
)
5845 #ifdef REG_PARM_STACK_SPACE
5847 restore_fixed_argument_area (save_area
, argblock
,
5848 high_to_save
, low_to_save
);
5851 /* If we saved any argument areas, restore them. */
5852 for (count
= 0; count
< nargs
; count
++)
5853 if (argvec
[count
].save_area
)
5855 machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
5856 rtx adr
= plus_constant (Pmode
, argblock
,
5857 argvec
[count
].locate
.offset
.constant
);
5858 rtx stack_area
= gen_rtx_MEM (save_mode
,
5859 memory_address (save_mode
, adr
));
5861 if (save_mode
== BLKmode
)
5862 emit_block_move (stack_area
,
5864 (copy_rtx (argvec
[count
].save_area
)),
5866 (argvec
[count
].locate
.size
.constant
, Pmode
)),
5867 BLOCK_OP_CALL_PARM
);
5869 emit_move_insn (stack_area
, argvec
[count
].save_area
);
5872 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
5873 stack_usage_map
= initial_stack_usage_map
;
5874 stack_usage_watermark
= initial_stack_usage_watermark
;
5877 free (stack_usage_map_buf
);
5884 /* Store a single argument for a function call
5885 into the register or memory area where it must be passed.
5886 *ARG describes the argument value and where to pass it.
5888 ARGBLOCK is the address of the stack-block for all the arguments,
5889 or 0 on a machine where arguments are pushed individually.
5891 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
5892 so must be careful about how the stack is used.
5894 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
5895 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
5896 that we need not worry about saving and restoring the stack.
5898 FNDECL is the declaration of the function we are calling.
5900 Return nonzero if this arg should cause sibcall failure,
5904 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
5905 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
5907 tree pval
= arg
->tree_value
;
5910 poly_int64 used
= 0;
5911 poly_int64 lower_bound
= 0, upper_bound
= 0;
5912 int sibcall_failure
= 0;
5914 if (TREE_CODE (pval
) == ERROR_MARK
)
5917 /* Push a new temporary level for any temporaries we make for
5921 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
5923 /* If this is being stored into a pre-allocated, fixed-size, stack area,
5924 save any previous data at that location. */
5925 if (argblock
&& ! variable_size
&& arg
->stack
)
5927 if (ARGS_GROW_DOWNWARD
)
5929 /* stack_slot is negative, but we want to index stack_usage_map
5930 with positive values. */
5931 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
5933 rtx offset
= XEXP (XEXP (arg
->stack_slot
, 0), 1);
5934 upper_bound
= -rtx_to_poly_int64 (offset
) + 1;
5939 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
5943 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
5945 rtx offset
= XEXP (XEXP (arg
->stack_slot
, 0), 1);
5946 lower_bound
= rtx_to_poly_int64 (offset
);
5951 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
5954 if (stack_region_maybe_used_p (lower_bound
, upper_bound
,
5955 reg_parm_stack_space
))
5957 /* We need to make a save area. */
5958 poly_uint64 size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
5959 machine_mode save_mode
5960 = int_mode_for_size (size
, 1).else_blk ();
5961 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
5962 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
5964 if (save_mode
== BLKmode
)
5967 = assign_temp (TREE_TYPE (arg
->tree_value
), 1, 1);
5968 preserve_temp_slots (arg
->save_area
);
5969 emit_block_move (validize_mem (copy_rtx (arg
->save_area
)),
5972 (arg
->locate
.size
.constant
, Pmode
)),
5973 BLOCK_OP_CALL_PARM
);
5977 arg
->save_area
= gen_reg_rtx (save_mode
);
5978 emit_move_insn (arg
->save_area
, stack_area
);
5984 /* If this isn't going to be placed on both the stack and in registers,
5985 set up the register and number of words. */
5986 if (! arg
->pass_on_stack
)
5988 if (flags
& ECF_SIBCALL
)
5989 reg
= arg
->tail_call_reg
;
5992 partial
= arg
->partial
;
5995 /* Being passed entirely in a register. We shouldn't be called in
5997 gcc_assert (reg
== 0 || partial
!= 0);
5999 /* If this arg needs special alignment, don't load the registers
6001 if (arg
->n_aligned_regs
!= 0)
6004 /* If this is being passed partially in a register, we can't evaluate
6005 it directly into its stack slot. Otherwise, we can. */
6006 if (arg
->value
== 0)
6008 /* stack_arg_under_construction is nonzero if a function argument is
6009 being evaluated directly into the outgoing argument list and
6010 expand_call must take special action to preserve the argument list
6011 if it is called recursively.
6013 For scalar function arguments stack_usage_map is sufficient to
6014 determine which stack slots must be saved and restored. Scalar
6015 arguments in general have pass_on_stack == 0.
6017 If this argument is initialized by a function which takes the
6018 address of the argument (a C++ constructor or a C function
6019 returning a BLKmode structure), then stack_usage_map is
6020 insufficient and expand_call must push the stack around the
6021 function call. Such arguments have pass_on_stack == 1.
6023 Note that it is always safe to set stack_arg_under_construction,
6024 but this generates suboptimal code if set when not needed. */
6026 if (arg
->pass_on_stack
)
6027 stack_arg_under_construction
++;
6029 arg
->value
= expand_expr (pval
,
6031 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
6032 ? NULL_RTX
: arg
->stack
,
6033 VOIDmode
, EXPAND_STACK_PARM
);
6035 /* If we are promoting object (or for any other reason) the mode
6036 doesn't agree, convert the mode. */
6038 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
6039 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
6040 arg
->value
, arg
->unsignedp
);
6042 if (arg
->pass_on_stack
)
6043 stack_arg_under_construction
--;
6046 /* Check for overlap with already clobbered argument area. */
6047 if ((flags
& ECF_SIBCALL
)
6048 && MEM_P (arg
->value
)
6049 && mem_might_overlap_already_clobbered_arg_p (XEXP (arg
->value
, 0),
6050 arg
->locate
.size
.constant
))
6051 sibcall_failure
= 1;
6053 /* Don't allow anything left on stack from computation
6054 of argument to alloca. */
6055 if (flags
& ECF_MAY_BE_ALLOCA
)
6056 do_pending_stack_adjust ();
6058 if (arg
->value
== arg
->stack
)
6059 /* If the value is already in the stack slot, we are done. */
6061 else if (arg
->mode
!= BLKmode
)
6063 unsigned int parm_align
;
6065 /* Argument is a scalar, not entirely passed in registers.
6066 (If part is passed in registers, arg->partial says how much
6067 and emit_push_insn will take care of putting it there.)
6069 Push it, and if its size is less than the
6070 amount of space allocated to it,
6071 also bump stack pointer by the additional space.
6072 Note that in C the default argument promotions
6073 will prevent such mismatches. */
6075 poly_int64 size
= (TYPE_EMPTY_P (TREE_TYPE (pval
))
6076 ? 0 : GET_MODE_SIZE (arg
->mode
));
6078 /* Compute how much space the push instruction will push.
6079 On many machines, pushing a byte will advance the stack
6080 pointer by a halfword. */
6081 #ifdef PUSH_ROUNDING
6082 size
= PUSH_ROUNDING (size
);
6086 /* Compute how much space the argument should get:
6087 round up to a multiple of the alignment for arguments. */
6088 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
6090 /* At the moment we don't (need to) support ABIs for which the
6091 padding isn't known at compile time. In principle it should
6092 be easy to add though. */
6093 used
= force_align_up (size
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
6095 /* Compute the alignment of the pushed argument. */
6096 parm_align
= arg
->locate
.boundary
;
6097 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
6100 poly_int64 pad
= used
- size
;
6101 unsigned int pad_align
= known_alignment (pad
) * BITS_PER_UNIT
;
6103 parm_align
= MIN (parm_align
, pad_align
);
6106 /* This isn't already where we want it on the stack, so put it there.
6107 This can either be done with push or copy insns. */
6108 if (maybe_ne (used
, 0)
6109 && !emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
),
6110 NULL_RTX
, parm_align
, partial
, reg
, used
- size
,
6111 argblock
, ARGS_SIZE_RTX (arg
->locate
.offset
),
6112 reg_parm_stack_space
,
6113 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
), true))
6114 sibcall_failure
= 1;
6116 /* Unless this is a partially-in-register argument, the argument is now
6119 arg
->value
= arg
->stack
;
6123 /* BLKmode, at least partly to be pushed. */
6125 unsigned int parm_align
;
6129 /* Pushing a nonscalar.
6130 If part is passed in registers, PARTIAL says how much
6131 and emit_push_insn will take care of putting it there. */
6133 /* Round its size up to a multiple
6134 of the allocation unit for arguments. */
6136 if (arg
->locate
.size
.var
!= 0)
6139 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
6143 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
6144 for BLKmode is careful to avoid it. */
6145 excess
= (arg
->locate
.size
.constant
6146 - arg_int_size_in_bytes (TREE_TYPE (pval
))
6148 size_rtx
= expand_expr (arg_size_in_bytes (TREE_TYPE (pval
)),
6149 NULL_RTX
, TYPE_MODE (sizetype
),
6153 parm_align
= arg
->locate
.boundary
;
6155 /* When an argument is padded down, the block is aligned to
6156 PARM_BOUNDARY, but the actual argument isn't. */
6157 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
6160 if (arg
->locate
.size
.var
)
6161 parm_align
= BITS_PER_UNIT
;
6164 unsigned int excess_align
6165 = known_alignment (excess
) * BITS_PER_UNIT
;
6166 if (excess_align
!= 0)
6167 parm_align
= MIN (parm_align
, excess_align
);
6171 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
6173 /* emit_push_insn might not work properly if arg->value and
6174 argblock + arg->locate.offset areas overlap. */
6178 if (strip_offset (XEXP (x
, 0), &i
)
6179 == crtl
->args
.internal_arg_pointer
)
6181 /* arg.locate doesn't contain the pretend_args_size offset,
6182 it's part of argblock. Ensure we don't count it in I. */
6183 if (STACK_GROWS_DOWNWARD
)
6184 i
-= crtl
->args
.pretend_args_size
;
6186 i
+= crtl
->args
.pretend_args_size
;
6188 /* expand_call should ensure this. */
6189 gcc_assert (!arg
->locate
.offset
.var
6190 && arg
->locate
.size
.var
== 0);
6191 poly_int64 size_val
= rtx_to_poly_int64 (size_rtx
);
6193 if (known_eq (arg
->locate
.offset
.constant
, i
))
6195 /* Even though they appear to be at the same location,
6196 if part of the outgoing argument is in registers,
6197 they aren't really at the same location. Check for
6198 this by making sure that the incoming size is the
6199 same as the outgoing size. */
6200 if (maybe_ne (arg
->locate
.size
.constant
, size_val
))
6201 sibcall_failure
= 1;
6203 else if (maybe_in_range_p (arg
->locate
.offset
.constant
,
6205 sibcall_failure
= 1;
6206 /* Use arg->locate.size.constant instead of size_rtx
6207 because we only care about the part of the argument
6209 else if (maybe_in_range_p (i
, arg
->locate
.offset
.constant
,
6210 arg
->locate
.size
.constant
))
6211 sibcall_failure
= 1;
6215 if (!CONST_INT_P (size_rtx
) || INTVAL (size_rtx
) != 0)
6216 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
6217 parm_align
, partial
, reg
, excess
, argblock
,
6218 ARGS_SIZE_RTX (arg
->locate
.offset
),
6219 reg_parm_stack_space
,
6220 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
), false);
6222 /* Unless this is a partially-in-register argument, the argument is now
6225 ??? Unlike the case above, in which we want the actual
6226 address of the data, so that we can load it directly into a
6227 register, here we want the address of the stack slot, so that
6228 it's properly aligned for word-by-word copying or something
6229 like that. It's not clear that this is always correct. */
6231 arg
->value
= arg
->stack_slot
;
6234 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
6236 tree type
= TREE_TYPE (arg
->tree_value
);
6238 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
6239 int_size_in_bytes (type
));
6242 /* Mark all slots this store used. */
6243 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
6244 && argblock
&& ! variable_size
&& arg
->stack
)
6245 mark_stack_region_used (lower_bound
, upper_bound
);
6247 /* Once we have pushed something, pops can't safely
6248 be deferred during the rest of the arguments. */
6251 /* Free any temporary slots made in processing this argument. */
6254 return sibcall_failure
;
6257 /* Nonzero if we do not know how to pass ARG solely in registers. */
6260 must_pass_in_stack_var_size (const function_arg_info
&arg
)
6265 /* If the type has variable size... */
6266 if (!poly_int_tree_p (TYPE_SIZE (arg
.type
)))
6269 /* If the type is marked as addressable (it is required
6270 to be constructed into the stack)... */
6271 if (TREE_ADDRESSABLE (arg
.type
))
6277 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
6278 takes trailing padding of a structure into account. */
6279 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
6282 must_pass_in_stack_var_size_or_pad (const function_arg_info
&arg
)
6287 /* If the type has variable size... */
6288 if (TREE_CODE (TYPE_SIZE (arg
.type
)) != INTEGER_CST
)
6291 /* If the type is marked as addressable (it is required
6292 to be constructed into the stack)... */
6293 if (TREE_ADDRESSABLE (arg
.type
))
6296 if (TYPE_EMPTY_P (arg
.type
))
6299 /* If the padding and mode of the type is such that a copy into
6300 a register would put it into the wrong part of the register. */
6301 if (arg
.mode
== BLKmode
6302 && int_size_in_bytes (arg
.type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
6303 && (targetm
.calls
.function_arg_padding (arg
.mode
, arg
.type
)
6304 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
6310 /* Return true if TYPE must be passed on the stack when passed to
6311 the "..." arguments of a function. */
6314 must_pass_va_arg_in_stack (tree type
)
6316 function_arg_info
arg (type
, /*named=*/false);
6317 return targetm
.calls
.must_pass_in_stack (arg
);
6320 /* Return true if FIELD is the C++17 empty base field that should
6321 be ignored for ABI calling convention decisions in order to
6322 maintain ABI compatibility between C++14 and earlier, which doesn't
6323 add this FIELD to classes with empty bases, and C++17 and later
6327 cxx17_empty_base_field_p (const_tree field
)
6329 return (DECL_FIELD_ABI_IGNORED (field
)
6330 && DECL_ARTIFICIAL (field
)
6331 && RECORD_OR_UNION_TYPE_P (TREE_TYPE (field
))
6332 && !lookup_attribute ("no_unique_address", DECL_ATTRIBUTES (field
)));
6335 /* Tell the garbage collector about GTY markers in this source file. */
6336 #include "gt-calls.h"