1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989-2019 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/>. */
22 #include "coretypes.h"
31 #include "stringpool.h"
36 #include "diagnostic-core.h"
37 #include "fold-const.h"
38 #include "stor-layout.h"
40 #include "internal-fn.h"
46 #include "langhooks.h"
51 #include "tree-ssanames.h"
52 #include "tree-ssa-strlen.h"
54 #include "stringpool.h"
57 #include "gimple-fold.h"
59 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
60 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
62 /* Data structure and subroutines used within expand_call. */
66 /* Tree node for this argument. */
68 /* Mode for value; TYPE_MODE unless promoted. */
70 /* Current RTL value for argument, or 0 if it isn't precomputed. */
72 /* Initially-compute RTL value for argument; only for const functions. */
74 /* Register to pass this argument in, 0 if passed on stack, or an
75 PARALLEL if the arg is to be copied into multiple non-contiguous
78 /* Register to pass this argument in when generating tail call sequence.
79 This is not the same register as for normal calls on machines with
82 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
83 form for emit_group_move. */
85 /* If REG was promoted from the actual mode of the argument expression,
86 indicates whether the promotion is sign- or zero-extended. */
88 /* Number of bytes to put in registers. 0 means put the whole arg
89 in registers. Also 0 if not passed in registers. */
91 /* Nonzero if argument must be passed on stack.
92 Note that some arguments may be passed on the stack
93 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
94 pass_on_stack identifies arguments that *cannot* go in registers. */
96 /* Some fields packaged up for locate_and_pad_parm. */
97 struct locate_and_pad_arg_data locate
;
98 /* Location on the stack at which parameter should be stored. The store
99 has already been done if STACK == VALUE. */
101 /* Location on the stack of the start of this argument slot. This can
102 differ from STACK if this arg pads downward. This location is known
103 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
105 /* Place that this stack area has been saved, if needed. */
107 /* If an argument's alignment does not permit direct copying into registers,
108 copy in smaller-sized pieces into pseudos. These are stored in a
109 block pointed to by this field. The next field says how many
110 word-sized pseudos we made. */
115 /* A vector of one char per byte of stack space. A byte if nonzero if
116 the corresponding stack location has been used.
117 This vector is used to prevent a function call within an argument from
118 clobbering any stack already set up. */
119 static char *stack_usage_map
;
121 /* Size of STACK_USAGE_MAP. */
122 static unsigned int highest_outgoing_arg_in_use
;
124 /* Assume that any stack location at this byte index is used,
125 without checking the contents of stack_usage_map. */
126 static unsigned HOST_WIDE_INT stack_usage_watermark
= HOST_WIDE_INT_M1U
;
128 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
129 stack location's tail call argument has been already stored into the stack.
130 This bitmap is used to prevent sibling call optimization if function tries
131 to use parent's incoming argument slots when they have been already
132 overwritten with tail call arguments. */
133 static sbitmap stored_args_map
;
135 /* Assume that any virtual-incoming location at this byte index has been
136 stored, without checking the contents of stored_args_map. */
137 static unsigned HOST_WIDE_INT stored_args_watermark
;
139 /* stack_arg_under_construction is nonzero when an argument may be
140 initialized with a constructor call (including a C function that
141 returns a BLKmode struct) and expand_call must take special action
142 to make sure the object being constructed does not overlap the
143 argument list for the constructor call. */
144 static int stack_arg_under_construction
;
146 static void precompute_register_parameters (int, struct arg_data
*, int *);
147 static int store_one_arg (struct arg_data
*, rtx
, int, int, int);
148 static void store_unaligned_arguments_into_pseudos (struct arg_data
*, int);
149 static int finalize_must_preallocate (int, int, struct arg_data
*,
151 static void precompute_arguments (int, struct arg_data
*);
152 static void compute_argument_addresses (struct arg_data
*, rtx
, int);
153 static rtx
rtx_for_function_call (tree
, tree
);
154 static void load_register_parameters (struct arg_data
*, int, rtx
*, int,
156 static int special_function_p (const_tree
, int);
157 static int check_sibcall_argument_overlap_1 (rtx
);
158 static int check_sibcall_argument_overlap (rtx_insn
*, struct arg_data
*, int);
160 static tree
split_complex_types (tree
);
162 #ifdef REG_PARM_STACK_SPACE
163 static rtx
save_fixed_argument_area (int, rtx
, int *, int *);
164 static void restore_fixed_argument_area (rtx
, rtx
, int, int);
167 /* Return true if bytes [LOWER_BOUND, UPPER_BOUND) of the outgoing
168 stack region might already be in use. */
171 stack_region_maybe_used_p (poly_uint64 lower_bound
, poly_uint64 upper_bound
,
172 unsigned int reg_parm_stack_space
)
174 unsigned HOST_WIDE_INT const_lower
, const_upper
;
175 const_lower
= constant_lower_bound (lower_bound
);
176 if (!upper_bound
.is_constant (&const_upper
))
177 const_upper
= HOST_WIDE_INT_M1U
;
179 if (const_upper
> stack_usage_watermark
)
182 /* Don't worry about things in the fixed argument area;
183 it has already been saved. */
184 const_lower
= MAX (const_lower
, reg_parm_stack_space
);
185 const_upper
= MIN (const_upper
, highest_outgoing_arg_in_use
);
186 for (unsigned HOST_WIDE_INT i
= const_lower
; i
< const_upper
; ++i
)
187 if (stack_usage_map
[i
])
192 /* Record that bytes [LOWER_BOUND, UPPER_BOUND) of the outgoing
193 stack region are now in use. */
196 mark_stack_region_used (poly_uint64 lower_bound
, poly_uint64 upper_bound
)
198 unsigned HOST_WIDE_INT const_lower
, const_upper
;
199 const_lower
= constant_lower_bound (lower_bound
);
200 if (upper_bound
.is_constant (&const_upper
))
201 for (unsigned HOST_WIDE_INT i
= const_lower
; i
< const_upper
; ++i
)
202 stack_usage_map
[i
] = 1;
204 stack_usage_watermark
= MIN (stack_usage_watermark
, const_lower
);
207 /* Force FUNEXP into a form suitable for the address of a CALL,
208 and return that as an rtx. Also load the static chain register
209 if FNDECL is a nested function.
211 CALL_FUSAGE points to a variable holding the prospective
212 CALL_INSN_FUNCTION_USAGE information. */
215 prepare_call_address (tree fndecl_or_type
, rtx funexp
, rtx static_chain_value
,
216 rtx
*call_fusage
, int reg_parm_seen
, int flags
)
218 /* Make a valid memory address and copy constants through pseudo-regs,
219 but not for a constant address if -fno-function-cse. */
220 if (GET_CODE (funexp
) != SYMBOL_REF
)
222 /* If it's an indirect call by descriptor, generate code to perform
223 runtime identification of the pointer and load the descriptor. */
224 if ((flags
& ECF_BY_DESCRIPTOR
) && !flag_trampolines
)
226 const int bit_val
= targetm
.calls
.custom_function_descriptors
;
227 rtx call_lab
= gen_label_rtx ();
229 gcc_assert (fndecl_or_type
&& TYPE_P (fndecl_or_type
));
231 = build_decl (UNKNOWN_LOCATION
, FUNCTION_DECL
, NULL_TREE
,
233 DECL_STATIC_CHAIN (fndecl_or_type
) = 1;
234 rtx chain
= targetm
.calls
.static_chain (fndecl_or_type
, false);
236 if (GET_MODE (funexp
) != Pmode
)
237 funexp
= convert_memory_address (Pmode
, funexp
);
239 /* Avoid long live ranges around function calls. */
240 funexp
= copy_to_mode_reg (Pmode
, funexp
);
243 emit_insn (gen_rtx_CLOBBER (VOIDmode
, chain
));
245 /* Emit the runtime identification pattern. */
246 rtx mask
= gen_rtx_AND (Pmode
, funexp
, GEN_INT (bit_val
));
247 emit_cmp_and_jump_insns (mask
, const0_rtx
, EQ
, NULL_RTX
, Pmode
, 1,
250 /* Statically predict the branch to very likely taken. */
251 rtx_insn
*insn
= get_last_insn ();
253 predict_insn_def (insn
, PRED_BUILTIN_EXPECT
, TAKEN
);
255 /* Load the descriptor. */
256 rtx mem
= gen_rtx_MEM (ptr_mode
,
257 plus_constant (Pmode
, funexp
, - bit_val
));
258 MEM_NOTRAP_P (mem
) = 1;
259 mem
= convert_memory_address (Pmode
, mem
);
260 emit_move_insn (chain
, mem
);
262 mem
= gen_rtx_MEM (ptr_mode
,
263 plus_constant (Pmode
, funexp
,
264 POINTER_SIZE
/ BITS_PER_UNIT
266 MEM_NOTRAP_P (mem
) = 1;
267 mem
= convert_memory_address (Pmode
, mem
);
268 emit_move_insn (funexp
, mem
);
270 emit_label (call_lab
);
274 use_reg (call_fusage
, chain
);
275 STATIC_CHAIN_REG_P (chain
) = 1;
278 /* Make sure we're not going to be overwritten below. */
279 gcc_assert (!static_chain_value
);
282 /* If we are using registers for parameters, force the
283 function address into a register now. */
284 funexp
= ((reg_parm_seen
285 && targetm
.small_register_classes_for_mode_p (FUNCTION_MODE
))
286 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
287 : memory_address (FUNCTION_MODE
, funexp
));
291 /* funexp could be a SYMBOL_REF represents a function pointer which is
292 of ptr_mode. In this case, it should be converted into address mode
293 to be a valid address for memory rtx pattern. See PR 64971. */
294 if (GET_MODE (funexp
) != Pmode
)
295 funexp
= convert_memory_address (Pmode
, funexp
);
297 if (!(flags
& ECF_SIBCALL
))
299 if (!NO_FUNCTION_CSE
&& optimize
&& ! flag_no_function_cse
)
300 funexp
= force_reg (Pmode
, funexp
);
304 if (static_chain_value
!= 0
305 && (TREE_CODE (fndecl_or_type
) != FUNCTION_DECL
306 || DECL_STATIC_CHAIN (fndecl_or_type
)))
310 chain
= targetm
.calls
.static_chain (fndecl_or_type
, false);
311 static_chain_value
= convert_memory_address (Pmode
, static_chain_value
);
313 emit_move_insn (chain
, static_chain_value
);
316 use_reg (call_fusage
, chain
);
317 STATIC_CHAIN_REG_P (chain
) = 1;
324 /* Generate instructions to call function FUNEXP,
325 and optionally pop the results.
326 The CALL_INSN is the first insn generated.
328 FNDECL is the declaration node of the function. This is given to the
329 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
332 FUNTYPE is the data type of the function. This is given to the hook
333 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
334 own args. We used to allow an identifier for library functions, but
335 that doesn't work when the return type is an aggregate type and the
336 calling convention says that the pointer to this aggregate is to be
337 popped by the callee.
339 STACK_SIZE is the number of bytes of arguments on the stack,
340 ROUNDED_STACK_SIZE is that number rounded up to
341 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
342 both to put into the call insn and to generate explicit popping
345 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
346 It is zero if this call doesn't want a structure value.
348 NEXT_ARG_REG is the rtx that results from executing
349 targetm.calls.function_arg (&args_so_far,
350 function_arg_info::end_marker ());
351 just after all the args have had their registers assigned.
352 This could be whatever you like, but normally it is the first
353 arg-register beyond those used for args in this call,
354 or 0 if all the arg-registers are used in this call.
355 It is passed on to `gen_call' so you can put this info in the call insn.
357 VALREG is a hard register in which a value is returned,
358 or 0 if the call does not return a value.
360 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
361 the args to this call were processed.
362 We restore `inhibit_defer_pop' to that value.
364 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
365 denote registers used by the called function. */
368 emit_call_1 (rtx funexp
, tree fntree ATTRIBUTE_UNUSED
, tree fndecl ATTRIBUTE_UNUSED
,
369 tree funtype ATTRIBUTE_UNUSED
,
370 poly_int64 stack_size ATTRIBUTE_UNUSED
,
371 poly_int64 rounded_stack_size
,
372 poly_int64 struct_value_size ATTRIBUTE_UNUSED
,
373 rtx next_arg_reg ATTRIBUTE_UNUSED
, rtx valreg
,
374 int old_inhibit_defer_pop
, rtx call_fusage
, int ecf_flags
,
375 cumulative_args_t args_so_far ATTRIBUTE_UNUSED
)
377 rtx rounded_stack_size_rtx
= gen_int_mode (rounded_stack_size
, Pmode
);
378 rtx call
, funmem
, pat
;
379 int already_popped
= 0;
380 poly_int64 n_popped
= 0;
382 /* Sibling call patterns never pop arguments (no sibcall(_value)_pop
383 patterns exist). Any popping that the callee does on return will
384 be from our caller's frame rather than ours. */
385 if (!(ecf_flags
& ECF_SIBCALL
))
387 n_popped
+= targetm
.calls
.return_pops_args (fndecl
, funtype
, stack_size
);
389 #ifdef CALL_POPS_ARGS
390 n_popped
+= CALL_POPS_ARGS (*get_cumulative_args (args_so_far
));
394 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
395 and we don't want to load it into a register as an optimization,
396 because prepare_call_address already did it if it should be done. */
397 if (GET_CODE (funexp
) != SYMBOL_REF
)
398 funexp
= memory_address (FUNCTION_MODE
, funexp
);
400 funmem
= gen_rtx_MEM (FUNCTION_MODE
, funexp
);
401 if (fndecl
&& TREE_CODE (fndecl
) == FUNCTION_DECL
)
405 /* Although a built-in FUNCTION_DECL and its non-__builtin
406 counterpart compare equal and get a shared mem_attrs, they
407 produce different dump output in compare-debug compilations,
408 if an entry gets garbage collected in one compilation, then
409 adds a different (but equivalent) entry, while the other
410 doesn't run the garbage collector at the same spot and then
411 shares the mem_attr with the equivalent entry. */
412 if (DECL_BUILT_IN_CLASS (t
) == BUILT_IN_NORMAL
)
414 tree t2
= builtin_decl_explicit (DECL_FUNCTION_CODE (t
));
419 set_mem_expr (funmem
, t
);
422 set_mem_expr (funmem
, build_simple_mem_ref (CALL_EXPR_FN (fntree
)));
424 if (ecf_flags
& ECF_SIBCALL
)
427 pat
= targetm
.gen_sibcall_value (valreg
, funmem
,
428 rounded_stack_size_rtx
,
429 next_arg_reg
, NULL_RTX
);
431 pat
= targetm
.gen_sibcall (funmem
, rounded_stack_size_rtx
,
433 gen_int_mode (struct_value_size
, Pmode
));
435 /* If the target has "call" or "call_value" insns, then prefer them
436 if no arguments are actually popped. If the target does not have
437 "call" or "call_value" insns, then we must use the popping versions
438 even if the call has no arguments to pop. */
439 else if (maybe_ne (n_popped
, 0)
441 ? targetm
.have_call_value ()
442 : targetm
.have_call ()))
444 rtx n_pop
= gen_int_mode (n_popped
, Pmode
);
446 /* If this subroutine pops its own args, record that in the call insn
447 if possible, for the sake of frame pointer elimination. */
450 pat
= targetm
.gen_call_value_pop (valreg
, funmem
,
451 rounded_stack_size_rtx
,
452 next_arg_reg
, n_pop
);
454 pat
= targetm
.gen_call_pop (funmem
, rounded_stack_size_rtx
,
455 next_arg_reg
, n_pop
);
462 pat
= targetm
.gen_call_value (valreg
, funmem
, rounded_stack_size_rtx
,
463 next_arg_reg
, NULL_RTX
);
465 pat
= targetm
.gen_call (funmem
, rounded_stack_size_rtx
, next_arg_reg
,
466 gen_int_mode (struct_value_size
, Pmode
));
470 /* Find the call we just emitted. */
471 rtx_call_insn
*call_insn
= last_call_insn ();
473 /* Some target create a fresh MEM instead of reusing the one provided
474 above. Set its MEM_EXPR. */
475 call
= get_call_rtx_from (call_insn
);
477 && MEM_EXPR (XEXP (call
, 0)) == NULL_TREE
478 && MEM_EXPR (funmem
) != NULL_TREE
)
479 set_mem_expr (XEXP (call
, 0), MEM_EXPR (funmem
));
481 /* Put the register usage information there. */
482 add_function_usage_to (call_insn
, call_fusage
);
484 /* If this is a const call, then set the insn's unchanging bit. */
485 if (ecf_flags
& ECF_CONST
)
486 RTL_CONST_CALL_P (call_insn
) = 1;
488 /* If this is a pure call, then set the insn's unchanging bit. */
489 if (ecf_flags
& ECF_PURE
)
490 RTL_PURE_CALL_P (call_insn
) = 1;
492 /* If this is a const call, then set the insn's unchanging bit. */
493 if (ecf_flags
& ECF_LOOPING_CONST_OR_PURE
)
494 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn
) = 1;
496 /* Create a nothrow REG_EH_REGION note, if needed. */
497 make_reg_eh_region_note (call_insn
, ecf_flags
, 0);
499 if (ecf_flags
& ECF_NORETURN
)
500 add_reg_note (call_insn
, REG_NORETURN
, const0_rtx
);
502 if (ecf_flags
& ECF_RETURNS_TWICE
)
504 add_reg_note (call_insn
, REG_SETJMP
, const0_rtx
);
505 cfun
->calls_setjmp
= 1;
508 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
510 /* Restore this now, so that we do defer pops for this call's args
511 if the context of the call as a whole permits. */
512 inhibit_defer_pop
= old_inhibit_defer_pop
;
514 if (maybe_ne (n_popped
, 0))
517 CALL_INSN_FUNCTION_USAGE (call_insn
)
518 = gen_rtx_EXPR_LIST (VOIDmode
,
519 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
520 CALL_INSN_FUNCTION_USAGE (call_insn
));
521 rounded_stack_size
-= n_popped
;
522 rounded_stack_size_rtx
= gen_int_mode (rounded_stack_size
, Pmode
);
523 stack_pointer_delta
-= n_popped
;
525 add_args_size_note (call_insn
, stack_pointer_delta
);
527 /* If popup is needed, stack realign must use DRAP */
528 if (SUPPORTS_STACK_ALIGNMENT
)
529 crtl
->need_drap
= true;
531 /* For noreturn calls when not accumulating outgoing args force
532 REG_ARGS_SIZE note to prevent crossjumping of calls with different
534 else if (!ACCUMULATE_OUTGOING_ARGS
&& (ecf_flags
& ECF_NORETURN
) != 0)
535 add_args_size_note (call_insn
, stack_pointer_delta
);
537 if (!ACCUMULATE_OUTGOING_ARGS
)
539 /* If returning from the subroutine does not automatically pop the args,
540 we need an instruction to pop them sooner or later.
541 Perhaps do it now; perhaps just record how much space to pop later.
543 If returning from the subroutine does pop the args, indicate that the
544 stack pointer will be changed. */
546 if (maybe_ne (rounded_stack_size
, 0))
548 if (ecf_flags
& ECF_NORETURN
)
549 /* Just pretend we did the pop. */
550 stack_pointer_delta
-= rounded_stack_size
;
551 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
552 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
553 pending_stack_adjust
+= rounded_stack_size
;
555 adjust_stack (rounded_stack_size_rtx
);
558 /* When we accumulate outgoing args, we must avoid any stack manipulations.
559 Restore the stack pointer to its original value now. Usually
560 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
561 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
562 popping variants of functions exist as well.
564 ??? We may optimize similar to defer_pop above, but it is
565 probably not worthwhile.
567 ??? It will be worthwhile to enable combine_stack_adjustments even for
569 else if (maybe_ne (n_popped
, 0))
570 anti_adjust_stack (gen_int_mode (n_popped
, Pmode
));
573 /* Determine if the function identified by FNDECL is one with
574 special properties we wish to know about. Modify FLAGS accordingly.
576 For example, if the function might return more than one time (setjmp), then
577 set ECF_RETURNS_TWICE.
579 Set ECF_MAY_BE_ALLOCA for any memory allocation function that might allocate
580 space from the stack such as alloca. */
583 special_function_p (const_tree fndecl
, int flags
)
585 tree name_decl
= DECL_NAME (fndecl
);
587 if (fndecl
&& name_decl
588 && IDENTIFIER_LENGTH (name_decl
) <= 11
589 /* Exclude functions not at the file scope, or not `extern',
590 since they are not the magic functions we would otherwise
592 FIXME: this should be handled with attributes, not with this
593 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
594 because you can declare fork() inside a function if you
596 && (DECL_CONTEXT (fndecl
) == NULL_TREE
597 || TREE_CODE (DECL_CONTEXT (fndecl
)) == TRANSLATION_UNIT_DECL
)
598 && TREE_PUBLIC (fndecl
))
600 const char *name
= IDENTIFIER_POINTER (name_decl
);
601 const char *tname
= name
;
603 /* We assume that alloca will always be called by name. It
604 makes no sense to pass it as a pointer-to-function to
605 anything that does not understand its behavior. */
606 if (IDENTIFIER_LENGTH (name_decl
) == 6
608 && ! strcmp (name
, "alloca"))
609 flags
|= ECF_MAY_BE_ALLOCA
;
611 /* Disregard prefix _ or __. */
620 /* ECF_RETURNS_TWICE is safe even for -ffreestanding. */
621 if (! strcmp (tname
, "setjmp")
622 || ! strcmp (tname
, "sigsetjmp")
623 || ! strcmp (name
, "savectx")
624 || ! strcmp (name
, "vfork")
625 || ! strcmp (name
, "getcontext"))
626 flags
|= ECF_RETURNS_TWICE
;
629 if (DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
630 && ALLOCA_FUNCTION_CODE_P (DECL_FUNCTION_CODE (fndecl
)))
631 flags
|= ECF_MAY_BE_ALLOCA
;
636 /* Similar to special_function_p; return a set of ERF_ flags for the
639 decl_return_flags (tree fndecl
)
642 tree type
= TREE_TYPE (fndecl
);
646 attr
= lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type
));
650 attr
= TREE_VALUE (TREE_VALUE (attr
));
651 if (!attr
|| TREE_STRING_LENGTH (attr
) < 1)
654 switch (TREE_STRING_POINTER (attr
)[0])
660 return ERF_RETURNS_ARG
| (TREE_STRING_POINTER (attr
)[0] - '1');
671 /* Return nonzero when FNDECL represents a call to setjmp. */
674 setjmp_call_p (const_tree fndecl
)
676 if (DECL_IS_RETURNS_TWICE (fndecl
))
677 return ECF_RETURNS_TWICE
;
678 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
682 /* Return true if STMT may be an alloca call. */
685 gimple_maybe_alloca_call_p (const gimple
*stmt
)
689 if (!is_gimple_call (stmt
))
692 fndecl
= gimple_call_fndecl (stmt
);
693 if (fndecl
&& (special_function_p (fndecl
, 0) & ECF_MAY_BE_ALLOCA
))
699 /* Return true if STMT is a builtin alloca call. */
702 gimple_alloca_call_p (const gimple
*stmt
)
706 if (!is_gimple_call (stmt
))
709 fndecl
= gimple_call_fndecl (stmt
);
710 if (fndecl
&& fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
711 switch (DECL_FUNCTION_CODE (fndecl
))
713 CASE_BUILT_IN_ALLOCA
:
714 return gimple_call_num_args (stmt
) > 0;
722 /* Return true when exp contains a builtin alloca call. */
725 alloca_call_p (const_tree exp
)
728 if (TREE_CODE (exp
) == CALL_EXPR
729 && (fndecl
= get_callee_fndecl (exp
))
730 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
731 switch (DECL_FUNCTION_CODE (fndecl
))
733 CASE_BUILT_IN_ALLOCA
:
742 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
743 function. Return FALSE otherwise. */
746 is_tm_builtin (const_tree fndecl
)
751 if (decl_is_tm_clone (fndecl
))
754 if (DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
756 switch (DECL_FUNCTION_CODE (fndecl
))
758 case BUILT_IN_TM_COMMIT
:
759 case BUILT_IN_TM_COMMIT_EH
:
760 case BUILT_IN_TM_ABORT
:
761 case BUILT_IN_TM_IRREVOCABLE
:
762 case BUILT_IN_TM_GETTMCLONE_IRR
:
763 case BUILT_IN_TM_MEMCPY
:
764 case BUILT_IN_TM_MEMMOVE
:
765 case BUILT_IN_TM_MEMSET
:
766 CASE_BUILT_IN_TM_STORE (1):
767 CASE_BUILT_IN_TM_STORE (2):
768 CASE_BUILT_IN_TM_STORE (4):
769 CASE_BUILT_IN_TM_STORE (8):
770 CASE_BUILT_IN_TM_STORE (FLOAT
):
771 CASE_BUILT_IN_TM_STORE (DOUBLE
):
772 CASE_BUILT_IN_TM_STORE (LDOUBLE
):
773 CASE_BUILT_IN_TM_STORE (M64
):
774 CASE_BUILT_IN_TM_STORE (M128
):
775 CASE_BUILT_IN_TM_STORE (M256
):
776 CASE_BUILT_IN_TM_LOAD (1):
777 CASE_BUILT_IN_TM_LOAD (2):
778 CASE_BUILT_IN_TM_LOAD (4):
779 CASE_BUILT_IN_TM_LOAD (8):
780 CASE_BUILT_IN_TM_LOAD (FLOAT
):
781 CASE_BUILT_IN_TM_LOAD (DOUBLE
):
782 CASE_BUILT_IN_TM_LOAD (LDOUBLE
):
783 CASE_BUILT_IN_TM_LOAD (M64
):
784 CASE_BUILT_IN_TM_LOAD (M128
):
785 CASE_BUILT_IN_TM_LOAD (M256
):
786 case BUILT_IN_TM_LOG
:
787 case BUILT_IN_TM_LOG_1
:
788 case BUILT_IN_TM_LOG_2
:
789 case BUILT_IN_TM_LOG_4
:
790 case BUILT_IN_TM_LOG_8
:
791 case BUILT_IN_TM_LOG_FLOAT
:
792 case BUILT_IN_TM_LOG_DOUBLE
:
793 case BUILT_IN_TM_LOG_LDOUBLE
:
794 case BUILT_IN_TM_LOG_M64
:
795 case BUILT_IN_TM_LOG_M128
:
796 case BUILT_IN_TM_LOG_M256
:
805 /* Detect flags (function attributes) from the function decl or type node. */
808 flags_from_decl_or_type (const_tree exp
)
814 /* The function exp may have the `malloc' attribute. */
815 if (DECL_IS_MALLOC (exp
))
818 /* The function exp may have the `returns_twice' attribute. */
819 if (DECL_IS_RETURNS_TWICE (exp
))
820 flags
|= ECF_RETURNS_TWICE
;
822 /* Process the pure and const attributes. */
823 if (TREE_READONLY (exp
))
825 if (DECL_PURE_P (exp
))
827 if (DECL_LOOPING_CONST_OR_PURE_P (exp
))
828 flags
|= ECF_LOOPING_CONST_OR_PURE
;
830 if (DECL_IS_NOVOPS (exp
))
832 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp
)))
834 if (lookup_attribute ("cold", DECL_ATTRIBUTES (exp
)))
837 if (TREE_NOTHROW (exp
))
838 flags
|= ECF_NOTHROW
;
842 if (is_tm_builtin (exp
))
843 flags
|= ECF_TM_BUILTIN
;
844 else if ((flags
& (ECF_CONST
|ECF_NOVOPS
)) != 0
845 || lookup_attribute ("transaction_pure",
846 TYPE_ATTRIBUTES (TREE_TYPE (exp
))))
847 flags
|= ECF_TM_PURE
;
850 flags
= special_function_p (exp
, flags
);
852 else if (TYPE_P (exp
))
854 if (TYPE_READONLY (exp
))
858 && ((flags
& ECF_CONST
) != 0
859 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp
))))
860 flags
|= ECF_TM_PURE
;
865 if (TREE_THIS_VOLATILE (exp
))
867 flags
|= ECF_NORETURN
;
868 if (flags
& (ECF_CONST
|ECF_PURE
))
869 flags
|= ECF_LOOPING_CONST_OR_PURE
;
875 /* Detect flags from a CALL_EXPR. */
878 call_expr_flags (const_tree t
)
881 tree decl
= get_callee_fndecl (t
);
884 flags
= flags_from_decl_or_type (decl
);
885 else if (CALL_EXPR_FN (t
) == NULL_TREE
)
886 flags
= internal_fn_flags (CALL_EXPR_IFN (t
));
889 tree type
= TREE_TYPE (CALL_EXPR_FN (t
));
890 if (type
&& TREE_CODE (type
) == POINTER_TYPE
)
891 flags
= flags_from_decl_or_type (TREE_TYPE (type
));
894 if (CALL_EXPR_BY_DESCRIPTOR (t
))
895 flags
|= ECF_BY_DESCRIPTOR
;
901 /* Return true if ARG should be passed by invisible reference. */
904 pass_by_reference (CUMULATIVE_ARGS
*ca
, function_arg_info arg
)
906 if (tree type
= arg
.type
)
908 /* If this type contains non-trivial constructors, then it is
909 forbidden for the middle-end to create any new copies. */
910 if (TREE_ADDRESSABLE (type
))
913 /* GCC post 3.4 passes *all* variable sized types by reference. */
914 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
917 /* If a record type should be passed the same as its first (and only)
918 member, use the type and mode of that member. */
919 if (TREE_CODE (type
) == RECORD_TYPE
&& TYPE_TRANSPARENT_AGGR (type
))
921 arg
.type
= TREE_TYPE (first_field (type
));
922 arg
.mode
= TYPE_MODE (arg
.type
);
926 return targetm
.calls
.pass_by_reference (pack_cumulative_args (ca
), arg
);
929 /* Return true if TYPE should be passed by reference when passed to
930 the "..." arguments of a function. */
933 pass_va_arg_by_reference (tree type
)
935 return pass_by_reference (NULL
, function_arg_info (type
, /*named=*/false));
938 /* Decide whether ARG, which occurs in the state described by CA,
939 should be passed by reference. Return true if so and update
943 apply_pass_by_reference_rules (CUMULATIVE_ARGS
*ca
, function_arg_info
&arg
)
945 if (pass_by_reference (ca
, arg
))
947 arg
.type
= build_pointer_type (arg
.type
);
948 arg
.mode
= TYPE_MODE (arg
.type
);
949 arg
.pass_by_reference
= true;
955 /* Return true if ARG, which is passed by reference, should be callee
956 copied instead of caller copied. */
959 reference_callee_copied (CUMULATIVE_ARGS
*ca
, const function_arg_info
&arg
)
961 if (arg
.type
&& TREE_ADDRESSABLE (arg
.type
))
963 return targetm
.calls
.callee_copies (pack_cumulative_args (ca
), arg
);
967 /* Precompute all register parameters as described by ARGS, storing values
968 into fields within the ARGS array.
970 NUM_ACTUALS indicates the total number elements in the ARGS array.
972 Set REG_PARM_SEEN if we encounter a register parameter. */
975 precompute_register_parameters (int num_actuals
, struct arg_data
*args
,
982 for (i
= 0; i
< num_actuals
; i
++)
983 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
987 if (args
[i
].value
== 0)
990 args
[i
].value
= expand_normal (args
[i
].tree_value
);
991 preserve_temp_slots (args
[i
].value
);
995 /* If we are to promote the function arg to a wider mode,
998 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
1000 = convert_modes (args
[i
].mode
,
1001 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
1002 args
[i
].value
, args
[i
].unsignedp
);
1004 /* If the value is a non-legitimate constant, force it into a
1005 pseudo now. TLS symbols sometimes need a call to resolve. */
1006 if (CONSTANT_P (args
[i
].value
)
1007 && !targetm
.legitimate_constant_p (args
[i
].mode
, args
[i
].value
))
1008 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
1010 /* If we're going to have to load the value by parts, pull the
1011 parts into pseudos. The part extraction process can involve
1012 non-trivial computation. */
1013 if (GET_CODE (args
[i
].reg
) == PARALLEL
)
1015 tree type
= TREE_TYPE (args
[i
].tree_value
);
1016 args
[i
].parallel_value
1017 = emit_group_load_into_temps (args
[i
].reg
, args
[i
].value
,
1018 type
, int_size_in_bytes (type
));
1021 /* If the value is expensive, and we are inside an appropriately
1022 short loop, put the value into a pseudo and then put the pseudo
1025 For small register classes, also do this if this call uses
1026 register parameters. This is to avoid reload conflicts while
1027 loading the parameters registers. */
1029 else if ((! (REG_P (args
[i
].value
)
1030 || (GET_CODE (args
[i
].value
) == SUBREG
1031 && REG_P (SUBREG_REG (args
[i
].value
)))))
1032 && args
[i
].mode
!= BLKmode
1033 && (set_src_cost (args
[i
].value
, args
[i
].mode
,
1034 optimize_insn_for_speed_p ())
1035 > COSTS_N_INSNS (1))
1037 && targetm
.small_register_classes_for_mode_p (args
[i
].mode
))
1039 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
1043 #ifdef REG_PARM_STACK_SPACE
1045 /* The argument list is the property of the called routine and it
1046 may clobber it. If the fixed area has been used for previous
1047 parameters, we must save and restore it. */
1050 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
1055 /* Compute the boundary of the area that needs to be saved, if any. */
1056 high
= reg_parm_stack_space
;
1057 if (ARGS_GROW_DOWNWARD
)
1060 if (high
> highest_outgoing_arg_in_use
)
1061 high
= highest_outgoing_arg_in_use
;
1063 for (low
= 0; low
< high
; low
++)
1064 if (stack_usage_map
[low
] != 0 || low
>= stack_usage_watermark
)
1067 machine_mode save_mode
;
1073 while (stack_usage_map
[--high
] == 0)
1077 *high_to_save
= high
;
1079 num_to_save
= high
- low
+ 1;
1081 /* If we don't have the required alignment, must do this
1083 scalar_int_mode imode
;
1084 if (int_mode_for_size (num_to_save
* BITS_PER_UNIT
, 1).exists (&imode
)
1085 && (low
& (MIN (GET_MODE_SIZE (imode
),
1086 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)) == 0)
1089 save_mode
= BLKmode
;
1091 if (ARGS_GROW_DOWNWARD
)
1096 addr
= plus_constant (Pmode
, argblock
, delta
);
1097 stack_area
= gen_rtx_MEM (save_mode
, memory_address (save_mode
, addr
));
1099 set_mem_align (stack_area
, PARM_BOUNDARY
);
1100 if (save_mode
== BLKmode
)
1102 save_area
= assign_stack_temp (BLKmode
, num_to_save
);
1103 emit_block_move (validize_mem (save_area
), stack_area
,
1104 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
1108 save_area
= gen_reg_rtx (save_mode
);
1109 emit_move_insn (save_area
, stack_area
);
1119 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
1121 machine_mode save_mode
= GET_MODE (save_area
);
1123 rtx addr
, stack_area
;
1125 if (ARGS_GROW_DOWNWARD
)
1126 delta
= -high_to_save
;
1128 delta
= low_to_save
;
1130 addr
= plus_constant (Pmode
, argblock
, delta
);
1131 stack_area
= gen_rtx_MEM (save_mode
, memory_address (save_mode
, addr
));
1132 set_mem_align (stack_area
, PARM_BOUNDARY
);
1134 if (save_mode
!= BLKmode
)
1135 emit_move_insn (stack_area
, save_area
);
1137 emit_block_move (stack_area
, validize_mem (save_area
),
1138 GEN_INT (high_to_save
- low_to_save
+ 1),
1139 BLOCK_OP_CALL_PARM
);
1141 #endif /* REG_PARM_STACK_SPACE */
1143 /* If any elements in ARGS refer to parameters that are to be passed in
1144 registers, but not in memory, and whose alignment does not permit a
1145 direct copy into registers. Copy the values into a group of pseudos
1146 which we will later copy into the appropriate hard registers.
1148 Pseudos for each unaligned argument will be stored into the array
1149 args[argnum].aligned_regs. The caller is responsible for deallocating
1150 the aligned_regs array if it is nonzero. */
1153 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
1157 for (i
= 0; i
< num_actuals
; i
++)
1158 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
1159 && GET_CODE (args
[i
].reg
) != PARALLEL
1160 && args
[i
].mode
== BLKmode
1161 && MEM_P (args
[i
].value
)
1162 && (MEM_ALIGN (args
[i
].value
)
1163 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
1165 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1166 int endian_correction
= 0;
1168 if (args
[i
].partial
)
1170 gcc_assert (args
[i
].partial
% UNITS_PER_WORD
== 0);
1171 args
[i
].n_aligned_regs
= args
[i
].partial
/ UNITS_PER_WORD
;
1175 args
[i
].n_aligned_regs
1176 = (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
1179 args
[i
].aligned_regs
= XNEWVEC (rtx
, args
[i
].n_aligned_regs
);
1181 /* Structures smaller than a word are normally aligned to the
1182 least significant byte. On a BYTES_BIG_ENDIAN machine,
1183 this means we must skip the empty high order bytes when
1184 calculating the bit offset. */
1185 if (bytes
< UNITS_PER_WORD
1186 #ifdef BLOCK_REG_PADDING
1187 && (BLOCK_REG_PADDING (args
[i
].mode
,
1188 TREE_TYPE (args
[i
].tree_value
), 1)
1194 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
1196 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1198 rtx reg
= gen_reg_rtx (word_mode
);
1199 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
1200 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
1202 args
[i
].aligned_regs
[j
] = reg
;
1203 word
= extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
1204 word_mode
, word_mode
, false, NULL
);
1206 /* There is no need to restrict this code to loading items
1207 in TYPE_ALIGN sized hunks. The bitfield instructions can
1208 load up entire word sized registers efficiently.
1210 ??? This may not be needed anymore.
1211 We use to emit a clobber here but that doesn't let later
1212 passes optimize the instructions we emit. By storing 0 into
1213 the register later passes know the first AND to zero out the
1214 bitfield being set in the register is unnecessary. The store
1215 of 0 will be deleted as will at least the first AND. */
1217 emit_move_insn (reg
, const0_rtx
);
1219 bytes
-= bitsize
/ BITS_PER_UNIT
;
1220 store_bit_field (reg
, bitsize
, endian_correction
, 0, 0,
1221 word_mode
, word
, false);
1226 /* The limit set by -Walloc-larger-than=. */
1227 static GTY(()) tree alloc_object_size_limit
;
1229 /* Initialize ALLOC_OBJECT_SIZE_LIMIT based on the -Walloc-size-larger-than=
1230 setting if the option is specified, or to the maximum object size if it
1231 is not. Return the initialized value. */
1234 alloc_max_size (void)
1236 if (alloc_object_size_limit
)
1237 return alloc_object_size_limit
;
1239 HOST_WIDE_INT limit
= warn_alloc_size_limit
;
1240 if (limit
== HOST_WIDE_INT_MAX
)
1241 limit
= tree_to_shwi (TYPE_MAX_VALUE (ptrdiff_type_node
));
1243 alloc_object_size_limit
= build_int_cst (size_type_node
, limit
);
1245 return alloc_object_size_limit
;
1248 /* Return true when EXP's range can be determined and set RANGE[] to it
1249 after adjusting it if necessary to make EXP a represents a valid size
1250 of object, or a valid size argument to an allocation function declared
1251 with attribute alloc_size (whose argument may be signed), or to a string
1252 manipulation function like memset. When ALLOW_ZERO is true, allow
1253 returning a range of [0, 0] for a size in an anti-range [1, N] where
1254 N > PTRDIFF_MAX. A zero range is a (nearly) invalid argument to
1255 allocation functions like malloc but it is a valid argument to
1256 functions like memset. */
1259 get_size_range (tree exp
, tree range
[2], bool allow_zero
/* = false */)
1261 if (tree_fits_uhwi_p (exp
))
1263 /* EXP is a constant. */
1264 range
[0] = range
[1] = exp
;
1268 tree exptype
= TREE_TYPE (exp
);
1269 bool integral
= INTEGRAL_TYPE_P (exptype
);
1272 enum value_range_kind range_type
;
1275 range_type
= determine_value_range (exp
, &min
, &max
);
1277 range_type
= VR_VARYING
;
1279 if (range_type
== VR_VARYING
)
1283 /* Use the full range of the type of the expression when
1284 no value range information is available. */
1285 range
[0] = TYPE_MIN_VALUE (exptype
);
1286 range
[1] = TYPE_MAX_VALUE (exptype
);
1290 range
[0] = NULL_TREE
;
1291 range
[1] = NULL_TREE
;
1295 unsigned expprec
= TYPE_PRECISION (exptype
);
1297 bool signed_p
= !TYPE_UNSIGNED (exptype
);
1299 if (range_type
== VR_ANTI_RANGE
)
1303 if (wi::les_p (max
, 0))
1305 /* EXP is not in a strictly negative range. That means
1306 it must be in some (not necessarily strictly) positive
1307 range which includes zero. Since in signed to unsigned
1308 conversions negative values end up converted to large
1309 positive values, and otherwise they are not valid sizes,
1310 the resulting range is in both cases [0, TYPE_MAX]. */
1311 min
= wi::zero (expprec
);
1312 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1314 else if (wi::les_p (min
- 1, 0))
1316 /* EXP is not in a negative-positive range. That means EXP
1317 is either negative, or greater than max. Since negative
1318 sizes are invalid make the range [MAX + 1, TYPE_MAX]. */
1320 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1325 min
= wi::zero (expprec
);
1328 else if (wi::eq_p (0, min
- 1))
1330 /* EXP is unsigned and not in the range [1, MAX]. That means
1331 it's either zero or greater than MAX. Even though 0 would
1332 normally be detected by -Walloc-zero, unless ALLOW_ZERO
1333 is true, set the range to [MAX, TYPE_MAX] so that when MAX
1334 is greater than the limit the whole range is diagnosed. */
1336 min
= max
= wi::zero (expprec
);
1340 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1346 min
= wi::zero (expprec
);
1350 range
[0] = wide_int_to_tree (exptype
, min
);
1351 range
[1] = wide_int_to_tree (exptype
, max
);
1356 /* Diagnose a call EXP to function FN decorated with attribute alloc_size
1357 whose argument numbers given by IDX with values given by ARGS exceed
1358 the maximum object size or cause an unsigned oveflow (wrapping) when
1359 multiplied. FN is null when EXP is a call via a function pointer.
1360 When ARGS[0] is null the function does nothing. ARGS[1] may be null
1361 for functions like malloc, and non-null for those like calloc that
1362 are decorated with a two-argument attribute alloc_size. */
1365 maybe_warn_alloc_args_overflow (tree fn
, tree exp
, tree args
[2], int idx
[2])
1367 /* The range each of the (up to) two arguments is known to be in. */
1368 tree argrange
[2][2] = { { NULL_TREE
, NULL_TREE
}, { NULL_TREE
, NULL_TREE
} };
1370 /* Maximum object size set by -Walloc-size-larger-than= or SIZE_MAX / 2. */
1371 tree maxobjsize
= alloc_max_size ();
1373 location_t loc
= EXPR_LOCATION (exp
);
1375 tree fntype
= fn
? TREE_TYPE (fn
) : TREE_TYPE (TREE_TYPE (exp
));
1376 bool warned
= false;
1378 /* Validate each argument individually. */
1379 for (unsigned i
= 0; i
!= 2 && args
[i
]; ++i
)
1381 if (TREE_CODE (args
[i
]) == INTEGER_CST
)
1383 argrange
[i
][0] = args
[i
];
1384 argrange
[i
][1] = args
[i
];
1386 if (tree_int_cst_lt (args
[i
], integer_zero_node
))
1388 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1389 "%Kargument %i value %qE is negative",
1390 exp
, idx
[i
] + 1, args
[i
]);
1392 else if (integer_zerop (args
[i
]))
1394 /* Avoid issuing -Walloc-zero for allocation functions other
1395 than __builtin_alloca that are declared with attribute
1396 returns_nonnull because there's no portability risk. This
1397 avoids warning for such calls to libiberty's xmalloc and
1399 Also avoid issuing the warning for calls to function named
1401 if (fn
&& fndecl_built_in_p (fn
, BUILT_IN_ALLOCA
)
1402 ? IDENTIFIER_LENGTH (DECL_NAME (fn
)) != 6
1403 : !lookup_attribute ("returns_nonnull",
1404 TYPE_ATTRIBUTES (fntype
)))
1405 warned
= warning_at (loc
, OPT_Walloc_zero
,
1406 "%Kargument %i value is zero",
1409 else if (tree_int_cst_lt (maxobjsize
, args
[i
]))
1411 /* G++ emits calls to ::operator new[](SIZE_MAX) in C++98
1412 mode and with -fno-exceptions as a way to indicate array
1413 size overflow. There's no good way to detect C++98 here
1414 so avoid diagnosing these calls for all C++ modes. */
1419 && DECL_IS_OPERATOR_NEW_P (fn
)
1420 && integer_all_onesp (args
[i
]))
1423 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1424 "%Kargument %i value %qE exceeds "
1425 "maximum object size %E",
1426 exp
, idx
[i
] + 1, args
[i
], maxobjsize
);
1429 else if (TREE_CODE (args
[i
]) == SSA_NAME
1430 && get_size_range (args
[i
], argrange
[i
]))
1432 /* Verify that the argument's range is not negative (including
1433 upper bound of zero). */
1434 if (tree_int_cst_lt (argrange
[i
][0], integer_zero_node
)
1435 && tree_int_cst_le (argrange
[i
][1], integer_zero_node
))
1437 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1438 "%Kargument %i range [%E, %E] is negative",
1440 argrange
[i
][0], argrange
[i
][1]);
1442 else if (tree_int_cst_lt (maxobjsize
, argrange
[i
][0]))
1444 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1445 "%Kargument %i range [%E, %E] exceeds "
1446 "maximum object size %E",
1448 argrange
[i
][0], argrange
[i
][1],
1457 /* For a two-argument alloc_size, validate the product of the two
1458 arguments if both of their values or ranges are known. */
1459 if (!warned
&& tree_fits_uhwi_p (argrange
[0][0])
1460 && argrange
[1][0] && tree_fits_uhwi_p (argrange
[1][0])
1461 && !integer_onep (argrange
[0][0])
1462 && !integer_onep (argrange
[1][0]))
1464 /* Check for overflow in the product of a function decorated with
1465 attribute alloc_size (X, Y). */
1466 unsigned szprec
= TYPE_PRECISION (size_type_node
);
1467 wide_int x
= wi::to_wide (argrange
[0][0], szprec
);
1468 wide_int y
= wi::to_wide (argrange
[1][0], szprec
);
1470 wi::overflow_type vflow
;
1471 wide_int prod
= wi::umul (x
, y
, &vflow
);
1474 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1475 "%Kproduct %<%E * %E%> of arguments %i and %i "
1476 "exceeds %<SIZE_MAX%>",
1477 exp
, argrange
[0][0], argrange
[1][0],
1478 idx
[0] + 1, idx
[1] + 1);
1479 else if (wi::ltu_p (wi::to_wide (maxobjsize
, szprec
), prod
))
1480 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1481 "%Kproduct %<%E * %E%> of arguments %i and %i "
1482 "exceeds maximum object size %E",
1483 exp
, argrange
[0][0], argrange
[1][0],
1484 idx
[0] + 1, idx
[1] + 1,
1489 /* Print the full range of each of the two arguments to make
1490 it clear when it is, in fact, in a range and not constant. */
1491 if (argrange
[0][0] != argrange
[0][1])
1492 inform (loc
, "argument %i in the range [%E, %E]",
1493 idx
[0] + 1, argrange
[0][0], argrange
[0][1]);
1494 if (argrange
[1][0] != argrange
[1][1])
1495 inform (loc
, "argument %i in the range [%E, %E]",
1496 idx
[1] + 1, argrange
[1][0], argrange
[1][1]);
1502 location_t fnloc
= DECL_SOURCE_LOCATION (fn
);
1504 if (DECL_IS_BUILTIN (fn
))
1506 "in a call to built-in allocation function %qD", fn
);
1509 "in a call to allocation function %qD declared here", fn
);
1513 /* If EXPR refers to a character array or pointer declared attribute
1514 nonstring return a decl for that array or pointer and set *REF to
1515 the referenced enclosing object or pointer. Otherwise returns
1519 get_attr_nonstring_decl (tree expr
, tree
*ref
)
1522 tree var
= NULL_TREE
;
1523 if (TREE_CODE (decl
) == SSA_NAME
)
1525 gimple
*def
= SSA_NAME_DEF_STMT (decl
);
1527 if (is_gimple_assign (def
))
1529 tree_code code
= gimple_assign_rhs_code (def
);
1530 if (code
== ADDR_EXPR
1531 || code
== COMPONENT_REF
1532 || code
== VAR_DECL
)
1533 decl
= gimple_assign_rhs1 (def
);
1536 var
= SSA_NAME_VAR (decl
);
1539 if (TREE_CODE (decl
) == ADDR_EXPR
)
1540 decl
= TREE_OPERAND (decl
, 0);
1542 /* To simplify calling code, store the referenced DECL regardless of
1543 the attribute determined below, but avoid storing the SSA_NAME_VAR
1544 obtained above (it's not useful for dataflow purposes). */
1548 /* Use the SSA_NAME_VAR that was determined above to see if it's
1549 declared nonstring. Otherwise drill down into the referenced
1553 else if (TREE_CODE (decl
) == ARRAY_REF
)
1554 decl
= TREE_OPERAND (decl
, 0);
1555 else if (TREE_CODE (decl
) == COMPONENT_REF
)
1556 decl
= TREE_OPERAND (decl
, 1);
1557 else if (TREE_CODE (decl
) == MEM_REF
)
1558 return get_attr_nonstring_decl (TREE_OPERAND (decl
, 0), ref
);
1561 && lookup_attribute ("nonstring", DECL_ATTRIBUTES (decl
)))
1567 /* Warn about passing a non-string array/pointer to a function that
1568 expects a nul-terminated string argument. */
1571 maybe_warn_nonstring_arg (tree fndecl
, tree exp
)
1573 if (!fndecl
|| !fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
1576 if (TREE_NO_WARNING (exp
) || !warn_stringop_overflow
)
1579 /* Avoid clearly invalid calls (more checking done below). */
1580 unsigned nargs
= call_expr_nargs (exp
);
1584 /* The bound argument to a bounded string function like strncpy. */
1585 tree bound
= NULL_TREE
;
1587 /* The longest known or possible string argument to one of the comparison
1588 functions. If the length is less than the bound it is used instead.
1589 Since the length is only used for warning and not for code generation
1590 disable strict mode in the calls to get_range_strlen below. */
1591 tree maxlen
= NULL_TREE
;
1593 /* It's safe to call "bounded" string functions with a non-string
1594 argument since the functions provide an explicit bound for this
1595 purpose. The exception is strncat where the bound may refer to
1596 either the destination or the source. */
1597 int fncode
= DECL_FUNCTION_CODE (fndecl
);
1600 case BUILT_IN_STRCMP
:
1601 case BUILT_IN_STRNCMP
:
1602 case BUILT_IN_STRNCASECMP
:
1604 /* For these, if one argument refers to one or more of a set
1605 of string constants or arrays of known size, determine
1606 the range of their known or possible lengths and use it
1607 conservatively as the bound for the unbounded function,
1608 and to adjust the range of the bound of the bounded ones. */
1609 for (unsigned argno
= 0;
1610 argno
< MIN (nargs
, 2)
1611 && !(maxlen
&& TREE_CODE (maxlen
) == INTEGER_CST
); argno
++)
1613 tree arg
= CALL_EXPR_ARG (exp
, argno
);
1614 if (!get_attr_nonstring_decl (arg
))
1616 c_strlen_data lendata
= { };
1617 get_range_strlen (arg
, &lendata
, /* eltsize = */ 1);
1618 maxlen
= lendata
.maxbound
;
1624 case BUILT_IN_STRNCAT
:
1625 case BUILT_IN_STPNCPY
:
1626 case BUILT_IN_STRNCPY
:
1628 bound
= CALL_EXPR_ARG (exp
, 2);
1631 case BUILT_IN_STRNDUP
:
1633 bound
= CALL_EXPR_ARG (exp
, 1);
1636 case BUILT_IN_STRNLEN
:
1638 tree arg
= CALL_EXPR_ARG (exp
, 0);
1639 if (!get_attr_nonstring_decl (arg
))
1641 c_strlen_data lendata
= { };
1642 get_range_strlen (arg
, &lendata
, /* eltsize = */ 1);
1643 maxlen
= lendata
.maxbound
;
1646 bound
= CALL_EXPR_ARG (exp
, 1);
1654 /* Determine the range of the bound argument (if specified). */
1655 tree bndrng
[2] = { NULL_TREE
, NULL_TREE
};
1659 get_size_range (bound
, bndrng
);
1662 location_t loc
= EXPR_LOCATION (exp
);
1666 /* Diagnose excessive bound prior the adjustment below and
1667 regardless of attribute nonstring. */
1668 tree maxobjsize
= max_object_size ();
1669 if (tree_int_cst_lt (maxobjsize
, bndrng
[0]))
1671 if (tree_int_cst_equal (bndrng
[0], bndrng
[1]))
1672 warning_at (loc
, OPT_Wstringop_overflow_
,
1673 "%K%qD specified bound %E "
1674 "exceeds maximum object size %E",
1675 exp
, fndecl
, bndrng
[0], maxobjsize
);
1677 warning_at (loc
, OPT_Wstringop_overflow_
,
1678 "%K%qD specified bound [%E, %E] "
1679 "exceeds maximum object size %E",
1680 exp
, fndecl
, bndrng
[0], bndrng
[1], maxobjsize
);
1685 if (maxlen
&& !integer_all_onesp (maxlen
))
1687 /* Add one for the nul. */
1688 maxlen
= const_binop (PLUS_EXPR
, TREE_TYPE (maxlen
), maxlen
,
1693 /* Conservatively use the upper bound of the lengths for
1694 both the lower and the upper bound of the operation. */
1697 bound
= void_type_node
;
1701 /* Replace the bound on the operation with the upper bound
1702 of the length of the string if the latter is smaller. */
1703 if (tree_int_cst_lt (maxlen
, bndrng
[0]))
1705 else if (tree_int_cst_lt (maxlen
, bndrng
[1]))
1710 /* Iterate over the built-in function's formal arguments and check
1711 each const char* against the actual argument. If the actual
1712 argument is declared attribute non-string issue a warning unless
1713 the argument's maximum length is bounded. */
1714 function_args_iterator it
;
1715 function_args_iter_init (&it
, TREE_TYPE (fndecl
));
1717 for (unsigned argno
= 0; ; ++argno
, function_args_iter_next (&it
))
1719 /* Avoid iterating past the declared argument in a call
1720 to function declared without a prototype. */
1724 tree argtype
= function_args_iter_cond (&it
);
1728 if (TREE_CODE (argtype
) != POINTER_TYPE
)
1731 argtype
= TREE_TYPE (argtype
);
1733 if (TREE_CODE (argtype
) != INTEGER_TYPE
1734 || !TYPE_READONLY (argtype
))
1737 argtype
= TYPE_MAIN_VARIANT (argtype
);
1738 if (argtype
!= char_type_node
)
1741 tree callarg
= CALL_EXPR_ARG (exp
, argno
);
1742 if (TREE_CODE (callarg
) == ADDR_EXPR
)
1743 callarg
= TREE_OPERAND (callarg
, 0);
1745 /* See if the destination is declared with attribute "nonstring". */
1746 tree decl
= get_attr_nonstring_decl (callarg
);
1750 /* The maximum number of array elements accessed. */
1751 offset_int wibnd
= 0;
1753 if (argno
&& fncode
== BUILT_IN_STRNCAT
)
1755 /* See if the bound in strncat is derived from the length
1756 of the strlen of the destination (as it's expected to be).
1757 If so, reset BOUND and FNCODE to trigger a warning. */
1758 tree dstarg
= CALL_EXPR_ARG (exp
, 0);
1759 if (is_strlen_related_p (dstarg
, bound
))
1761 /* The bound applies to the destination, not to the source,
1762 so reset these to trigger a warning without mentioning
1768 /* Use the upper bound of the range for strncat. */
1769 wibnd
= wi::to_offset (bndrng
[1]);
1772 /* Use the lower bound of the range for functions other than
1774 wibnd
= wi::to_offset (bndrng
[0]);
1776 /* Determine the size of the argument array if it is one. */
1777 offset_int asize
= wibnd
;
1778 bool known_size
= false;
1779 tree type
= TREE_TYPE (decl
);
1781 /* Determine the array size. For arrays of unknown bound and
1782 pointers reset BOUND to trigger the appropriate warning. */
1783 if (TREE_CODE (type
) == ARRAY_TYPE
)
1785 if (tree arrbnd
= TYPE_DOMAIN (type
))
1787 if ((arrbnd
= TYPE_MAX_VALUE (arrbnd
)))
1789 asize
= wi::to_offset (arrbnd
) + 1;
1793 else if (bound
== void_type_node
)
1796 else if (bound
== void_type_node
)
1799 /* In a call to strncat with a bound in a range whose lower but
1800 not upper bound is less than the array size, reset ASIZE to
1801 be the same as the bound and the other variable to trigger
1802 the apprpriate warning below. */
1803 if (fncode
== BUILT_IN_STRNCAT
1804 && bndrng
[0] != bndrng
[1]
1805 && wi::ltu_p (wi::to_offset (bndrng
[0]), asize
)
1807 || wi::ltu_p (asize
, wibnd
)))
1814 bool warned
= false;
1816 auto_diagnostic_group d
;
1817 if (wi::ltu_p (asize
, wibnd
))
1819 if (bndrng
[0] == bndrng
[1])
1820 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1821 "%qD argument %i declared attribute "
1822 "%<nonstring%> is smaller than the specified "
1824 fndecl
, argno
+ 1, wibnd
.to_uhwi ());
1825 else if (wi::ltu_p (asize
, wi::to_offset (bndrng
[0])))
1826 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1827 "%qD argument %i declared attribute "
1828 "%<nonstring%> is smaller than "
1829 "the specified bound [%E, %E]",
1830 fndecl
, argno
+ 1, bndrng
[0], bndrng
[1]);
1832 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1833 "%qD argument %i declared attribute "
1834 "%<nonstring%> may be smaller than "
1835 "the specified bound [%E, %E]",
1836 fndecl
, argno
+ 1, bndrng
[0], bndrng
[1]);
1838 else if (fncode
== BUILT_IN_STRNCAT
)
1839 ; /* Avoid warning for calls to strncat() when the bound
1840 is equal to the size of the non-string argument. */
1842 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1843 "%qD argument %i declared attribute %<nonstring%>",
1847 inform (DECL_SOURCE_LOCATION (decl
),
1848 "argument %qD declared here", decl
);
1852 /* Issue an error if CALL_EXPR was flagged as requiring
1853 tall-call optimization. */
1856 maybe_complain_about_tail_call (tree call_expr
, const char *reason
)
1858 gcc_assert (TREE_CODE (call_expr
) == CALL_EXPR
);
1859 if (!CALL_EXPR_MUST_TAIL_CALL (call_expr
))
1862 error_at (EXPR_LOCATION (call_expr
), "cannot tail-call: %s", reason
);
1865 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1868 NUM_ACTUALS is the total number of parameters.
1870 N_NAMED_ARGS is the total number of named arguments.
1872 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1875 FNDECL is the tree code for the target of this call (if known)
1877 ARGS_SO_FAR holds state needed by the target to know where to place
1880 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1881 for arguments which are passed in registers.
1883 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1884 and may be modified by this routine.
1886 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1887 flags which may be modified by this routine.
1889 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1890 that requires allocation of stack space.
1892 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1893 the thunked-to function. */
1896 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
1897 struct arg_data
*args
,
1898 struct args_size
*args_size
,
1899 int n_named_args ATTRIBUTE_UNUSED
,
1900 tree exp
, tree struct_value_addr_value
,
1901 tree fndecl
, tree fntype
,
1902 cumulative_args_t args_so_far
,
1903 int reg_parm_stack_space
,
1904 rtx
*old_stack_level
,
1905 poly_int64_pod
*old_pending_adj
,
1906 int *must_preallocate
, int *ecf_flags
,
1907 bool *may_tailcall
, bool call_from_thunk_p
)
1909 CUMULATIVE_ARGS
*args_so_far_pnt
= get_cumulative_args (args_so_far
);
1910 location_t loc
= EXPR_LOCATION (exp
);
1912 /* Count arg position in order args appear. */
1917 args_size
->constant
= 0;
1920 bitmap_obstack_initialize (NULL
);
1922 /* In this loop, we consider args in the order they are written.
1923 We fill up ARGS from the back. */
1925 i
= num_actuals
- 1;
1928 call_expr_arg_iterator iter
;
1930 bitmap slots
= NULL
;
1932 if (struct_value_addr_value
)
1934 args
[j
].tree_value
= struct_value_addr_value
;
1938 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
1940 tree argtype
= TREE_TYPE (arg
);
1942 if (targetm
.calls
.split_complex_arg
1944 && TREE_CODE (argtype
) == COMPLEX_TYPE
1945 && targetm
.calls
.split_complex_arg (argtype
))
1947 tree subtype
= TREE_TYPE (argtype
);
1948 args
[j
].tree_value
= build1 (REALPART_EXPR
, subtype
, arg
);
1950 args
[j
].tree_value
= build1 (IMAGPART_EXPR
, subtype
, arg
);
1953 args
[j
].tree_value
= arg
;
1959 BITMAP_FREE (slots
);
1962 bitmap_obstack_release (NULL
);
1964 /* Extract attribute alloc_size from the type of the called expression
1965 (which could be a function or a function pointer) and if set, store
1966 the indices of the corresponding arguments in ALLOC_IDX, and then
1967 the actual argument(s) at those indices in ALLOC_ARGS. */
1968 int alloc_idx
[2] = { -1, -1 };
1969 if (tree alloc_size
= lookup_attribute ("alloc_size",
1970 TYPE_ATTRIBUTES (fntype
)))
1972 tree args
= TREE_VALUE (alloc_size
);
1973 alloc_idx
[0] = TREE_INT_CST_LOW (TREE_VALUE (args
)) - 1;
1974 if (TREE_CHAIN (args
))
1975 alloc_idx
[1] = TREE_INT_CST_LOW (TREE_VALUE (TREE_CHAIN (args
))) - 1;
1978 /* Array for up to the two attribute alloc_size arguments. */
1979 tree alloc_args
[] = { NULL_TREE
, NULL_TREE
};
1981 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1982 for (argpos
= 0; argpos
< num_actuals
; i
--, argpos
++)
1984 tree type
= TREE_TYPE (args
[i
].tree_value
);
1987 /* Replace erroneous argument with constant zero. */
1988 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1989 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1991 /* If TYPE is a transparent union or record, pass things the way
1992 we would pass the first field of the union or record. We have
1993 already verified that the modes are the same. */
1994 if (RECORD_OR_UNION_TYPE_P (type
) && TYPE_TRANSPARENT_AGGR (type
))
1995 type
= TREE_TYPE (first_field (type
));
1997 /* Decide where to pass this arg.
1999 args[i].reg is nonzero if all or part is passed in registers.
2001 args[i].partial is nonzero if part but not all is passed in registers,
2002 and the exact value says how many bytes are passed in registers.
2004 args[i].pass_on_stack is nonzero if the argument must at least be
2005 computed on the stack. It may then be loaded back into registers
2006 if args[i].reg is nonzero.
2008 These decisions are driven by the FUNCTION_... macros and must agree
2009 with those made by function.c. */
2011 /* See if this argument should be passed by invisible reference. */
2012 function_arg_info
arg (type
, argpos
< n_named_args
);
2013 if (pass_by_reference (args_so_far_pnt
, arg
))
2016 tree base
= NULL_TREE
;
2018 callee_copies
= reference_callee_copied (args_so_far_pnt
, arg
);
2020 /* If we're compiling a thunk, pass through invisible references
2021 instead of making a copy. */
2022 if (call_from_thunk_p
2024 && !TREE_ADDRESSABLE (type
)
2025 && (base
= get_base_address (args
[i
].tree_value
))
2026 && TREE_CODE (base
) != SSA_NAME
2027 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
)))))
2029 /* We may have turned the parameter value into an SSA name.
2030 Go back to the original parameter so we can take the
2032 if (TREE_CODE (args
[i
].tree_value
) == SSA_NAME
)
2034 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args
[i
].tree_value
));
2035 args
[i
].tree_value
= SSA_NAME_VAR (args
[i
].tree_value
);
2036 gcc_assert (TREE_CODE (args
[i
].tree_value
) == PARM_DECL
);
2038 /* Argument setup code may have copied the value to register. We
2039 revert that optimization now because the tail call code must
2040 use the original location. */
2041 if (TREE_CODE (args
[i
].tree_value
) == PARM_DECL
2042 && !MEM_P (DECL_RTL (args
[i
].tree_value
))
2043 && DECL_INCOMING_RTL (args
[i
].tree_value
)
2044 && MEM_P (DECL_INCOMING_RTL (args
[i
].tree_value
)))
2045 set_decl_rtl (args
[i
].tree_value
,
2046 DECL_INCOMING_RTL (args
[i
].tree_value
));
2048 mark_addressable (args
[i
].tree_value
);
2050 /* We can't use sibcalls if a callee-copied argument is
2051 stored in the current function's frame. */
2052 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
2054 *may_tailcall
= false;
2055 maybe_complain_about_tail_call (exp
,
2056 "a callee-copied argument is"
2057 " stored in the current"
2058 " function's frame");
2061 args
[i
].tree_value
= build_fold_addr_expr_loc (loc
,
2062 args
[i
].tree_value
);
2063 type
= TREE_TYPE (args
[i
].tree_value
);
2065 if (*ecf_flags
& ECF_CONST
)
2066 *ecf_flags
&= ~(ECF_CONST
| ECF_LOOPING_CONST_OR_PURE
);
2070 /* We make a copy of the object and pass the address to the
2071 function being called. */
2074 if (!COMPLETE_TYPE_P (type
)
2075 || TREE_CODE (TYPE_SIZE_UNIT (type
)) != INTEGER_CST
2076 || (flag_stack_check
== GENERIC_STACK_CHECK
2077 && compare_tree_int (TYPE_SIZE_UNIT (type
),
2078 STACK_CHECK_MAX_VAR_SIZE
) > 0))
2080 /* This is a variable-sized object. Make space on the stack
2082 rtx size_rtx
= expr_size (args
[i
].tree_value
);
2084 if (*old_stack_level
== 0)
2086 emit_stack_save (SAVE_BLOCK
, old_stack_level
);
2087 *old_pending_adj
= pending_stack_adjust
;
2088 pending_stack_adjust
= 0;
2091 /* We can pass TRUE as the 4th argument because we just
2092 saved the stack pointer and will restore it right after
2094 copy
= allocate_dynamic_stack_space (size_rtx
,
2097 max_int_size_in_bytes
2100 copy
= gen_rtx_MEM (BLKmode
, copy
);
2101 set_mem_attributes (copy
, type
, 1);
2104 copy
= assign_temp (type
, 1, 0);
2106 store_expr (args
[i
].tree_value
, copy
, 0, false, false);
2108 /* Just change the const function to pure and then let
2109 the next test clear the pure based on
2111 if (*ecf_flags
& ECF_CONST
)
2113 *ecf_flags
&= ~ECF_CONST
;
2114 *ecf_flags
|= ECF_PURE
;
2117 if (!callee_copies
&& *ecf_flags
& ECF_PURE
)
2118 *ecf_flags
&= ~(ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
2121 = build_fold_addr_expr_loc (loc
, make_tree (type
, copy
));
2122 type
= TREE_TYPE (args
[i
].tree_value
);
2123 *may_tailcall
= false;
2124 maybe_complain_about_tail_call (exp
,
2125 "argument must be passed"
2128 arg
.pass_by_reference
= true;
2131 unsignedp
= TYPE_UNSIGNED (type
);
2134 = promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
2135 fndecl
? TREE_TYPE (fndecl
) : fntype
, 0);
2137 args
[i
].unsignedp
= unsignedp
;
2138 args
[i
].mode
= arg
.mode
;
2140 targetm
.calls
.warn_parameter_passing_abi (args_so_far
, type
);
2142 args
[i
].reg
= targetm
.calls
.function_arg (args_so_far
, arg
);
2144 if (args
[i
].reg
&& CONST_INT_P (args
[i
].reg
))
2147 /* If this is a sibling call and the machine has register windows, the
2148 register window has to be unwinded before calling the routine, so
2149 arguments have to go into the incoming registers. */
2150 if (targetm
.calls
.function_incoming_arg
!= targetm
.calls
.function_arg
)
2151 args
[i
].tail_call_reg
2152 = targetm
.calls
.function_incoming_arg (args_so_far
, arg
);
2154 args
[i
].tail_call_reg
= args
[i
].reg
;
2157 args
[i
].partial
= targetm
.calls
.arg_partial_bytes (args_so_far
, arg
);
2159 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (arg
);
2161 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
2162 it means that we are to pass this arg in the register(s) designated
2163 by the PARALLEL, but also to pass it in the stack. */
2164 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
2165 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
2166 args
[i
].pass_on_stack
= 1;
2168 /* If this is an addressable type, we must preallocate the stack
2169 since we must evaluate the object into its final location.
2171 If this is to be passed in both registers and the stack, it is simpler
2173 if (TREE_ADDRESSABLE (type
)
2174 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
2175 *must_preallocate
= 1;
2177 /* Compute the stack-size of this argument. */
2178 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
2179 || reg_parm_stack_space
> 0
2180 || args
[i
].pass_on_stack
)
2181 locate_and_pad_parm (arg
.mode
, type
,
2182 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2187 reg_parm_stack_space
,
2188 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
2189 fndecl
, args_size
, &args
[i
].locate
);
2190 #ifdef BLOCK_REG_PADDING
2192 /* The argument is passed entirely in registers. See at which
2193 end it should be padded. */
2194 args
[i
].locate
.where_pad
=
2195 BLOCK_REG_PADDING (arg
.mode
, type
,
2196 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
2199 /* Update ARGS_SIZE, the total stack space for args so far. */
2201 args_size
->constant
+= args
[i
].locate
.size
.constant
;
2202 if (args
[i
].locate
.size
.var
)
2203 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
2205 /* Increment ARGS_SO_FAR, which has info about which arg-registers
2206 have been used, etc. */
2208 /* ??? Traditionally we've passed TYPE_MODE here, instead of the
2209 promoted_mode used for function_arg above. However, the
2210 corresponding handling of incoming arguments in function.c
2211 does pass the promoted mode. */
2212 arg
.mode
= TYPE_MODE (type
);
2213 targetm
.calls
.function_arg_advance (args_so_far
, arg
);
2215 /* Store argument values for functions decorated with attribute
2217 if (argpos
== alloc_idx
[0])
2218 alloc_args
[0] = args
[i
].tree_value
;
2219 else if (argpos
== alloc_idx
[1])
2220 alloc_args
[1] = args
[i
].tree_value
;
2225 /* Check the arguments of functions decorated with attribute
2227 maybe_warn_alloc_args_overflow (fndecl
, exp
, alloc_args
, alloc_idx
);
2230 /* Detect passing non-string arguments to functions expecting
2231 nul-terminated strings. */
2232 maybe_warn_nonstring_arg (fndecl
, exp
);
2235 /* Update ARGS_SIZE to contain the total size for the argument block.
2236 Return the original constant component of the argument block's size.
2238 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
2239 for arguments passed in registers. */
2242 compute_argument_block_size (int reg_parm_stack_space
,
2243 struct args_size
*args_size
,
2244 tree fndecl ATTRIBUTE_UNUSED
,
2245 tree fntype ATTRIBUTE_UNUSED
,
2246 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
2248 poly_int64 unadjusted_args_size
= args_size
->constant
;
2250 /* For accumulate outgoing args mode we don't need to align, since the frame
2251 will be already aligned. Align to STACK_BOUNDARY in order to prevent
2252 backends from generating misaligned frame sizes. */
2253 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
2254 preferred_stack_boundary
= STACK_BOUNDARY
;
2256 /* Compute the actual size of the argument block required. The variable
2257 and constant sizes must be combined, the size may have to be rounded,
2258 and there may be a minimum required size. */
2262 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
2263 args_size
->constant
= 0;
2265 preferred_stack_boundary
/= BITS_PER_UNIT
;
2266 if (preferred_stack_boundary
> 1)
2268 /* We don't handle this case yet. To handle it correctly we have
2269 to add the delta, round and subtract the delta.
2270 Currently no machine description requires this support. */
2271 gcc_assert (multiple_p (stack_pointer_delta
,
2272 preferred_stack_boundary
));
2273 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
2276 if (reg_parm_stack_space
> 0)
2279 = size_binop (MAX_EXPR
, args_size
->var
,
2280 ssize_int (reg_parm_stack_space
));
2282 /* The area corresponding to register parameters is not to count in
2283 the size of the block we need. So make the adjustment. */
2284 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2286 = size_binop (MINUS_EXPR
, args_size
->var
,
2287 ssize_int (reg_parm_stack_space
));
2292 preferred_stack_boundary
/= BITS_PER_UNIT
;
2293 if (preferred_stack_boundary
< 1)
2294 preferred_stack_boundary
= 1;
2295 args_size
->constant
= (aligned_upper_bound (args_size
->constant
2296 + stack_pointer_delta
,
2297 preferred_stack_boundary
)
2298 - stack_pointer_delta
);
2300 args_size
->constant
= upper_bound (args_size
->constant
,
2301 reg_parm_stack_space
);
2303 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2304 args_size
->constant
-= reg_parm_stack_space
;
2306 return unadjusted_args_size
;
2309 /* Precompute parameters as needed for a function call.
2311 FLAGS is mask of ECF_* constants.
2313 NUM_ACTUALS is the number of arguments.
2315 ARGS is an array containing information for each argument; this
2316 routine fills in the INITIAL_VALUE and VALUE fields for each
2317 precomputed argument. */
2320 precompute_arguments (int num_actuals
, struct arg_data
*args
)
2324 /* If this is a libcall, then precompute all arguments so that we do not
2325 get extraneous instructions emitted as part of the libcall sequence. */
2327 /* If we preallocated the stack space, and some arguments must be passed
2328 on the stack, then we must precompute any parameter which contains a
2329 function call which will store arguments on the stack.
2330 Otherwise, evaluating the parameter may clobber previous parameters
2331 which have already been stored into the stack. (we have code to avoid
2332 such case by saving the outgoing stack arguments, but it results in
2334 if (!ACCUMULATE_OUTGOING_ARGS
)
2337 for (i
= 0; i
< num_actuals
; i
++)
2342 if (TREE_CODE (args
[i
].tree_value
) != CALL_EXPR
)
2345 /* If this is an addressable type, we cannot pre-evaluate it. */
2346 type
= TREE_TYPE (args
[i
].tree_value
);
2347 gcc_assert (!TREE_ADDRESSABLE (type
));
2349 args
[i
].initial_value
= args
[i
].value
2350 = expand_normal (args
[i
].tree_value
);
2352 mode
= TYPE_MODE (type
);
2353 if (mode
!= args
[i
].mode
)
2355 int unsignedp
= args
[i
].unsignedp
;
2357 = convert_modes (args
[i
].mode
, mode
,
2358 args
[i
].value
, args
[i
].unsignedp
);
2360 /* CSE will replace this only if it contains args[i].value
2361 pseudo, so convert it down to the declared mode using
2363 if (REG_P (args
[i
].value
)
2364 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
2365 && promote_mode (type
, mode
, &unsignedp
) != args
[i
].mode
)
2367 args
[i
].initial_value
2368 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
2369 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
2370 SUBREG_PROMOTED_SET (args
[i
].initial_value
, args
[i
].unsignedp
);
2376 /* Given the current state of MUST_PREALLOCATE and information about
2377 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
2378 compute and return the final value for MUST_PREALLOCATE. */
2381 finalize_must_preallocate (int must_preallocate
, int num_actuals
,
2382 struct arg_data
*args
, struct args_size
*args_size
)
2384 /* See if we have or want to preallocate stack space.
2386 If we would have to push a partially-in-regs parm
2387 before other stack parms, preallocate stack space instead.
2389 If the size of some parm is not a multiple of the required stack
2390 alignment, we must preallocate.
2392 If the total size of arguments that would otherwise create a copy in
2393 a temporary (such as a CALL) is more than half the total argument list
2394 size, preallocation is faster.
2396 Another reason to preallocate is if we have a machine (like the m88k)
2397 where stack alignment is required to be maintained between every
2398 pair of insns, not just when the call is made. However, we assume here
2399 that such machines either do not have push insns (and hence preallocation
2400 would occur anyway) or the problem is taken care of with
2403 if (! must_preallocate
)
2405 int partial_seen
= 0;
2406 poly_int64 copy_to_evaluate_size
= 0;
2409 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
2411 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
2413 else if (partial_seen
&& args
[i
].reg
== 0)
2414 must_preallocate
= 1;
2416 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
2417 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
2418 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
2419 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
2420 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
2421 copy_to_evaluate_size
2422 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
2425 if (maybe_ne (args_size
->constant
, 0)
2426 && maybe_ge (copy_to_evaluate_size
* 2, args_size
->constant
))
2427 must_preallocate
= 1;
2429 return must_preallocate
;
2432 /* If we preallocated stack space, compute the address of each argument
2433 and store it into the ARGS array.
2435 We need not ensure it is a valid memory address here; it will be
2436 validized when it is used.
2438 ARGBLOCK is an rtx for the address of the outgoing arguments. */
2441 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
2445 rtx arg_reg
= argblock
;
2447 poly_int64 arg_offset
= 0;
2449 if (GET_CODE (argblock
) == PLUS
)
2451 arg_reg
= XEXP (argblock
, 0);
2452 arg_offset
= rtx_to_poly_int64 (XEXP (argblock
, 1));
2455 for (i
= 0; i
< num_actuals
; i
++)
2457 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
2458 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
2460 unsigned int align
, boundary
;
2461 poly_uint64 units_on_stack
= 0;
2462 machine_mode partial_mode
= VOIDmode
;
2464 /* Skip this parm if it will not be passed on the stack. */
2465 if (! args
[i
].pass_on_stack
2467 && args
[i
].partial
== 0)
2470 if (TYPE_EMPTY_P (TREE_TYPE (args
[i
].tree_value
)))
2473 addr
= simplify_gen_binary (PLUS
, Pmode
, arg_reg
, offset
);
2474 addr
= plus_constant (Pmode
, addr
, arg_offset
);
2476 if (args
[i
].partial
!= 0)
2478 /* Only part of the parameter is being passed on the stack.
2479 Generate a simple memory reference of the correct size. */
2480 units_on_stack
= args
[i
].locate
.size
.constant
;
2481 poly_uint64 bits_on_stack
= units_on_stack
* BITS_PER_UNIT
;
2482 partial_mode
= int_mode_for_size (bits_on_stack
, 1).else_blk ();
2483 args
[i
].stack
= gen_rtx_MEM (partial_mode
, addr
);
2484 set_mem_size (args
[i
].stack
, units_on_stack
);
2488 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
2489 set_mem_attributes (args
[i
].stack
,
2490 TREE_TYPE (args
[i
].tree_value
), 1);
2492 align
= BITS_PER_UNIT
;
2493 boundary
= args
[i
].locate
.boundary
;
2494 poly_int64 offset_val
;
2495 if (args
[i
].locate
.where_pad
!= PAD_DOWNWARD
)
2497 else if (poly_int_rtx_p (offset
, &offset_val
))
2499 align
= least_bit_hwi (boundary
);
2500 unsigned int offset_align
2501 = known_alignment (offset_val
) * BITS_PER_UNIT
;
2502 if (offset_align
!= 0)
2503 align
= MIN (align
, offset_align
);
2505 set_mem_align (args
[i
].stack
, align
);
2507 addr
= simplify_gen_binary (PLUS
, Pmode
, arg_reg
, slot_offset
);
2508 addr
= plus_constant (Pmode
, addr
, arg_offset
);
2510 if (args
[i
].partial
!= 0)
2512 /* Only part of the parameter is being passed on the stack.
2513 Generate a simple memory reference of the correct size.
2515 args
[i
].stack_slot
= gen_rtx_MEM (partial_mode
, addr
);
2516 set_mem_size (args
[i
].stack_slot
, units_on_stack
);
2520 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
2521 set_mem_attributes (args
[i
].stack_slot
,
2522 TREE_TYPE (args
[i
].tree_value
), 1);
2524 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
2526 /* Function incoming arguments may overlap with sibling call
2527 outgoing arguments and we cannot allow reordering of reads
2528 from function arguments with stores to outgoing arguments
2529 of sibling calls. */
2530 set_mem_alias_set (args
[i
].stack
, 0);
2531 set_mem_alias_set (args
[i
].stack_slot
, 0);
2536 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
2537 in a call instruction.
2539 FNDECL is the tree node for the target function. For an indirect call
2540 FNDECL will be NULL_TREE.
2542 ADDR is the operand 0 of CALL_EXPR for this call. */
2545 rtx_for_function_call (tree fndecl
, tree addr
)
2549 /* Get the function to call, in the form of RTL. */
2552 if (!TREE_USED (fndecl
) && fndecl
!= current_function_decl
)
2553 TREE_USED (fndecl
) = 1;
2555 /* Get a SYMBOL_REF rtx for the function address. */
2556 funexp
= XEXP (DECL_RTL (fndecl
), 0);
2559 /* Generate an rtx (probably a pseudo-register) for the address. */
2562 funexp
= expand_normal (addr
);
2563 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
2568 /* Return the static chain for this function, if any. */
2571 rtx_for_static_chain (const_tree fndecl_or_type
, bool incoming_p
)
2573 if (DECL_P (fndecl_or_type
) && !DECL_STATIC_CHAIN (fndecl_or_type
))
2576 return targetm
.calls
.static_chain (fndecl_or_type
, incoming_p
);
2579 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
2582 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
2583 or NULL_RTX if none has been scanned yet. */
2584 rtx_insn
*scan_start
;
2585 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
2586 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
2587 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
2588 with fixed offset, or PC if this is with variable or unknown offset. */
2590 } internal_arg_pointer_exp_state
;
2592 static rtx
internal_arg_pointer_based_exp (const_rtx
, bool);
2594 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
2595 the tail call sequence, starting with first insn that hasn't been
2596 scanned yet, and note for each pseudo on the LHS whether it is based
2597 on crtl->args.internal_arg_pointer or not, and what offset from that
2598 that pointer it has. */
2601 internal_arg_pointer_based_exp_scan (void)
2603 rtx_insn
*insn
, *scan_start
= internal_arg_pointer_exp_state
.scan_start
;
2605 if (scan_start
== NULL_RTX
)
2606 insn
= get_insns ();
2608 insn
= NEXT_INSN (scan_start
);
2612 rtx set
= single_set (insn
);
2613 if (set
&& REG_P (SET_DEST (set
)) && !HARD_REGISTER_P (SET_DEST (set
)))
2616 unsigned int idx
= REGNO (SET_DEST (set
)) - FIRST_PSEUDO_REGISTER
;
2617 /* Punt on pseudos set multiple times. */
2618 if (idx
< internal_arg_pointer_exp_state
.cache
.length ()
2619 && (internal_arg_pointer_exp_state
.cache
[idx
]
2623 val
= internal_arg_pointer_based_exp (SET_SRC (set
), false);
2624 if (val
!= NULL_RTX
)
2626 if (idx
>= internal_arg_pointer_exp_state
.cache
.length ())
2627 internal_arg_pointer_exp_state
.cache
2628 .safe_grow_cleared (idx
+ 1);
2629 internal_arg_pointer_exp_state
.cache
[idx
] = val
;
2632 if (NEXT_INSN (insn
) == NULL_RTX
)
2634 insn
= NEXT_INSN (insn
);
2637 internal_arg_pointer_exp_state
.scan_start
= scan_start
;
2640 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
2641 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
2642 it with fixed offset, or PC if this is with variable or unknown offset.
2643 TOPLEVEL is true if the function is invoked at the topmost level. */
2646 internal_arg_pointer_based_exp (const_rtx rtl
, bool toplevel
)
2648 if (CONSTANT_P (rtl
))
2651 if (rtl
== crtl
->args
.internal_arg_pointer
)
2654 if (REG_P (rtl
) && HARD_REGISTER_P (rtl
))
2658 if (GET_CODE (rtl
) == PLUS
&& poly_int_rtx_p (XEXP (rtl
, 1), &offset
))
2660 rtx val
= internal_arg_pointer_based_exp (XEXP (rtl
, 0), toplevel
);
2661 if (val
== NULL_RTX
|| val
== pc_rtx
)
2663 return plus_constant (Pmode
, val
, offset
);
2666 /* When called at the topmost level, scan pseudo assignments in between the
2667 last scanned instruction in the tail call sequence and the latest insn
2668 in that sequence. */
2670 internal_arg_pointer_based_exp_scan ();
2674 unsigned int idx
= REGNO (rtl
) - FIRST_PSEUDO_REGISTER
;
2675 if (idx
< internal_arg_pointer_exp_state
.cache
.length ())
2676 return internal_arg_pointer_exp_state
.cache
[idx
];
2681 subrtx_iterator::array_type array
;
2682 FOR_EACH_SUBRTX (iter
, array
, rtl
, NONCONST
)
2684 const_rtx x
= *iter
;
2685 if (REG_P (x
) && internal_arg_pointer_based_exp (x
, false) != NULL_RTX
)
2688 iter
.skip_subrtxes ();
2694 /* Return true if SIZE bytes starting from address ADDR might overlap an
2695 already-clobbered argument area. This function is used to determine
2696 if we should give up a sibcall. */
2699 mem_might_overlap_already_clobbered_arg_p (rtx addr
, poly_uint64 size
)
2702 unsigned HOST_WIDE_INT start
, end
;
2705 if (bitmap_empty_p (stored_args_map
)
2706 && stored_args_watermark
== HOST_WIDE_INT_M1U
)
2708 val
= internal_arg_pointer_based_exp (addr
, true);
2709 if (val
== NULL_RTX
)
2711 else if (!poly_int_rtx_p (val
, &i
))
2714 if (known_eq (size
, 0U))
2717 if (STACK_GROWS_DOWNWARD
)
2718 i
-= crtl
->args
.pretend_args_size
;
2720 i
+= crtl
->args
.pretend_args_size
;
2722 if (ARGS_GROW_DOWNWARD
)
2725 /* We can ignore any references to the function's pretend args,
2726 which at this point would manifest as negative values of I. */
2727 if (known_le (i
, 0) && known_le (size
, poly_uint64 (-i
)))
2730 start
= maybe_lt (i
, 0) ? 0 : constant_lower_bound (i
);
2731 if (!(i
+ size
).is_constant (&end
))
2732 end
= HOST_WIDE_INT_M1U
;
2734 if (end
> stored_args_watermark
)
2737 end
= MIN (end
, SBITMAP_SIZE (stored_args_map
));
2738 for (unsigned HOST_WIDE_INT k
= start
; k
< end
; ++k
)
2739 if (bitmap_bit_p (stored_args_map
, k
))
2745 /* Do the register loads required for any wholly-register parms or any
2746 parms which are passed both on the stack and in a register. Their
2747 expressions were already evaluated.
2749 Mark all register-parms as living through the call, putting these USE
2750 insns in the CALL_INSN_FUNCTION_USAGE field.
2752 When IS_SIBCALL, perform the check_sibcall_argument_overlap
2753 checking, setting *SIBCALL_FAILURE if appropriate. */
2756 load_register_parameters (struct arg_data
*args
, int num_actuals
,
2757 rtx
*call_fusage
, int flags
, int is_sibcall
,
2758 int *sibcall_failure
)
2762 for (i
= 0; i
< num_actuals
; i
++)
2764 rtx reg
= ((flags
& ECF_SIBCALL
)
2765 ? args
[i
].tail_call_reg
: args
[i
].reg
);
2768 int partial
= args
[i
].partial
;
2770 poly_int64 size
= 0;
2771 HOST_WIDE_INT const_size
= 0;
2772 rtx_insn
*before_arg
= get_last_insn ();
2773 tree type
= TREE_TYPE (args
[i
].tree_value
);
2774 if (RECORD_OR_UNION_TYPE_P (type
) && TYPE_TRANSPARENT_AGGR (type
))
2775 type
= TREE_TYPE (first_field (type
));
2776 /* Set non-negative if we must move a word at a time, even if
2777 just one word (e.g, partial == 4 && mode == DFmode). Set
2778 to -1 if we just use a normal move insn. This value can be
2779 zero if the argument is a zero size structure. */
2781 if (GET_CODE (reg
) == PARALLEL
)
2785 gcc_assert (partial
% UNITS_PER_WORD
== 0);
2786 nregs
= partial
/ UNITS_PER_WORD
;
2788 else if (TYPE_MODE (type
) == BLKmode
)
2790 /* Variable-sized parameters should be described by a
2791 PARALLEL instead. */
2792 const_size
= int_size_in_bytes (type
);
2793 gcc_assert (const_size
>= 0);
2794 nregs
= (const_size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
2798 size
= GET_MODE_SIZE (args
[i
].mode
);
2800 /* Handle calls that pass values in multiple non-contiguous
2801 locations. The Irix 6 ABI has examples of this. */
2803 if (GET_CODE (reg
) == PARALLEL
)
2804 emit_group_move (reg
, args
[i
].parallel_value
);
2806 /* If simple case, just do move. If normal partial, store_one_arg
2807 has already loaded the register for us. In all other cases,
2808 load the register(s) from memory. */
2810 else if (nregs
== -1)
2812 emit_move_insn (reg
, args
[i
].value
);
2813 #ifdef BLOCK_REG_PADDING
2814 /* Handle case where we have a value that needs shifting
2815 up to the msb. eg. a QImode value and we're padding
2816 upward on a BYTES_BIG_ENDIAN machine. */
2817 if (args
[i
].locate
.where_pad
2818 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
))
2820 gcc_checking_assert (ordered_p (size
, UNITS_PER_WORD
));
2821 if (maybe_lt (size
, UNITS_PER_WORD
))
2825 = (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2827 /* Assigning REG here rather than a temp makes
2828 CALL_FUSAGE report the whole reg as used.
2829 Strictly speaking, the call only uses SIZE
2830 bytes at the msb end, but it doesn't seem worth
2831 generating rtl to say that. */
2832 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
2833 x
= expand_shift (LSHIFT_EXPR
, word_mode
,
2834 reg
, shift
, reg
, 1);
2836 emit_move_insn (reg
, x
);
2842 /* If we have pre-computed the values to put in the registers in
2843 the case of non-aligned structures, copy them in now. */
2845 else if (args
[i
].n_aligned_regs
!= 0)
2846 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
2847 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
2848 args
[i
].aligned_regs
[j
]);
2850 else if (partial
== 0 || args
[i
].pass_on_stack
)
2852 /* SIZE and CONST_SIZE are 0 for partial arguments and
2853 the size of a BLKmode type otherwise. */
2854 gcc_checking_assert (known_eq (size
, const_size
));
2855 rtx mem
= validize_mem (copy_rtx (args
[i
].value
));
2857 /* Check for overlap with already clobbered argument area,
2858 providing that this has non-zero size. */
2861 && (mem_might_overlap_already_clobbered_arg_p
2862 (XEXP (args
[i
].value
, 0), const_size
)))
2863 *sibcall_failure
= 1;
2865 if (const_size
% UNITS_PER_WORD
== 0
2866 || MEM_ALIGN (mem
) % BITS_PER_WORD
== 0)
2867 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
2871 move_block_to_reg (REGNO (reg
), mem
, nregs
- 1,
2873 rtx dest
= gen_rtx_REG (word_mode
, REGNO (reg
) + nregs
- 1);
2874 unsigned int bitoff
= (nregs
- 1) * BITS_PER_WORD
;
2875 unsigned int bitsize
= const_size
* BITS_PER_UNIT
- bitoff
;
2876 rtx x
= extract_bit_field (mem
, bitsize
, bitoff
, 1, dest
,
2877 word_mode
, word_mode
, false,
2879 if (BYTES_BIG_ENDIAN
)
2880 x
= expand_shift (LSHIFT_EXPR
, word_mode
, x
,
2881 BITS_PER_WORD
- bitsize
, dest
, 1);
2883 emit_move_insn (dest
, x
);
2886 /* Handle a BLKmode that needs shifting. */
2887 if (nregs
== 1 && const_size
< UNITS_PER_WORD
2888 #ifdef BLOCK_REG_PADDING
2889 && args
[i
].locate
.where_pad
== PAD_DOWNWARD
2895 rtx dest
= gen_rtx_REG (word_mode
, REGNO (reg
));
2896 int shift
= (UNITS_PER_WORD
- const_size
) * BITS_PER_UNIT
;
2897 enum tree_code dir
= (BYTES_BIG_ENDIAN
2898 ? RSHIFT_EXPR
: LSHIFT_EXPR
);
2901 x
= expand_shift (dir
, word_mode
, dest
, shift
, dest
, 1);
2903 emit_move_insn (dest
, x
);
2907 /* When a parameter is a block, and perhaps in other cases, it is
2908 possible that it did a load from an argument slot that was
2909 already clobbered. */
2911 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
2912 *sibcall_failure
= 1;
2914 /* Handle calls that pass values in multiple non-contiguous
2915 locations. The Irix 6 ABI has examples of this. */
2916 if (GET_CODE (reg
) == PARALLEL
)
2917 use_group_regs (call_fusage
, reg
);
2918 else if (nregs
== -1)
2919 use_reg_mode (call_fusage
, reg
, TYPE_MODE (type
));
2921 use_regs (call_fusage
, REGNO (reg
), nregs
);
2926 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2927 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2928 bytes, then we would need to push some additional bytes to pad the
2929 arguments. So, we try to compute an adjust to the stack pointer for an
2930 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2931 bytes. Then, when the arguments are pushed the stack will be perfectly
2934 Return true if this optimization is possible, storing the adjustment
2935 in ADJUSTMENT_OUT and setting ARGS_SIZE->CONSTANT to the number of
2936 bytes that should be popped after the call. */
2939 combine_pending_stack_adjustment_and_call (poly_int64_pod
*adjustment_out
,
2940 poly_int64 unadjusted_args_size
,
2941 struct args_size
*args_size
,
2942 unsigned int preferred_unit_stack_boundary
)
2944 /* The number of bytes to pop so that the stack will be
2945 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2946 poly_int64 adjustment
;
2947 /* The alignment of the stack after the arguments are pushed, if we
2948 just pushed the arguments without adjust the stack here. */
2949 unsigned HOST_WIDE_INT unadjusted_alignment
;
2951 if (!known_misalignment (stack_pointer_delta
+ unadjusted_args_size
,
2952 preferred_unit_stack_boundary
,
2953 &unadjusted_alignment
))
2956 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2957 as possible -- leaving just enough left to cancel out the
2958 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2959 PENDING_STACK_ADJUST is non-negative, and congruent to
2960 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2962 /* Begin by trying to pop all the bytes. */
2963 unsigned HOST_WIDE_INT tmp_misalignment
;
2964 if (!known_misalignment (pending_stack_adjust
,
2965 preferred_unit_stack_boundary
,
2968 unadjusted_alignment
-= tmp_misalignment
;
2969 adjustment
= pending_stack_adjust
;
2970 /* Push enough additional bytes that the stack will be aligned
2971 after the arguments are pushed. */
2972 if (preferred_unit_stack_boundary
> 1 && unadjusted_alignment
)
2973 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
2975 /* We need to know whether the adjusted argument size
2976 (UNADJUSTED_ARGS_SIZE - ADJUSTMENT) constitutes an allocation
2977 or a deallocation. */
2978 if (!ordered_p (adjustment
, unadjusted_args_size
))
2981 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2982 bytes after the call. The right number is the entire
2983 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2984 by the arguments in the first place. */
2986 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
2988 *adjustment_out
= adjustment
;
2992 /* Scan X expression if it does not dereference any argument slots
2993 we already clobbered by tail call arguments (as noted in stored_args_map
2995 Return nonzero if X expression dereferences such argument slots,
2999 check_sibcall_argument_overlap_1 (rtx x
)
3008 code
= GET_CODE (x
);
3010 /* We need not check the operands of the CALL expression itself. */
3015 return (mem_might_overlap_already_clobbered_arg_p
3016 (XEXP (x
, 0), GET_MODE_SIZE (GET_MODE (x
))));
3018 /* Scan all subexpressions. */
3019 fmt
= GET_RTX_FORMAT (code
);
3020 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
3024 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
3027 else if (*fmt
== 'E')
3029 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
3030 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
3037 /* Scan sequence after INSN if it does not dereference any argument slots
3038 we already clobbered by tail call arguments (as noted in stored_args_map
3039 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
3040 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
3041 should be 0). Return nonzero if sequence after INSN dereferences such argument
3042 slots, zero otherwise. */
3045 check_sibcall_argument_overlap (rtx_insn
*insn
, struct arg_data
*arg
,
3046 int mark_stored_args_map
)
3048 poly_uint64 low
, high
;
3049 unsigned HOST_WIDE_INT const_low
, const_high
;
3051 if (insn
== NULL_RTX
)
3052 insn
= get_insns ();
3054 insn
= NEXT_INSN (insn
);
3056 for (; insn
; insn
= NEXT_INSN (insn
))
3058 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
3061 if (mark_stored_args_map
)
3063 if (ARGS_GROW_DOWNWARD
)
3064 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
3066 low
= arg
->locate
.slot_offset
.constant
;
3067 high
= low
+ arg
->locate
.size
.constant
;
3069 const_low
= constant_lower_bound (low
);
3070 if (high
.is_constant (&const_high
))
3071 for (unsigned HOST_WIDE_INT i
= const_low
; i
< const_high
; ++i
)
3072 bitmap_set_bit (stored_args_map
, i
);
3074 stored_args_watermark
= MIN (stored_args_watermark
, const_low
);
3076 return insn
!= NULL_RTX
;
3079 /* Given that a function returns a value of mode MODE at the most
3080 significant end of hard register VALUE, shift VALUE left or right
3081 as specified by LEFT_P. Return true if some action was needed. */
3084 shift_return_value (machine_mode mode
, bool left_p
, rtx value
)
3086 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
3087 machine_mode value_mode
= GET_MODE (value
);
3088 poly_int64 shift
= GET_MODE_BITSIZE (value_mode
) - GET_MODE_BITSIZE (mode
);
3090 if (known_eq (shift
, 0))
3093 /* Use ashr rather than lshr for right shifts. This is for the benefit
3094 of the MIPS port, which requires SImode values to be sign-extended
3095 when stored in 64-bit registers. */
3096 if (!force_expand_binop (value_mode
, left_p
? ashl_optab
: ashr_optab
,
3097 value
, gen_int_shift_amount (value_mode
, shift
),
3098 value
, 1, OPTAB_WIDEN
))
3103 /* If X is a likely-spilled register value, copy it to a pseudo
3104 register and return that register. Return X otherwise. */
3107 avoid_likely_spilled_reg (rtx x
)
3112 && HARD_REGISTER_P (x
)
3113 && targetm
.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x
))))
3115 /* Make sure that we generate a REG rather than a CONCAT.
3116 Moves into CONCATs can need nontrivial instructions,
3117 and the whole point of this function is to avoid
3118 using the hard register directly in such a situation. */
3119 generating_concat_p
= 0;
3120 new_rtx
= gen_reg_rtx (GET_MODE (x
));
3121 generating_concat_p
= 1;
3122 emit_move_insn (new_rtx
, x
);
3128 /* Helper function for expand_call.
3129 Return false is EXP is not implementable as a sibling call. */
3132 can_implement_as_sibling_call_p (tree exp
,
3133 rtx structure_value_addr
,
3135 int reg_parm_stack_space ATTRIBUTE_UNUSED
,
3139 const args_size
&args_size
)
3141 if (!targetm
.have_sibcall_epilogue ())
3143 maybe_complain_about_tail_call
3145 "machine description does not have"
3146 " a sibcall_epilogue instruction pattern");
3150 /* Doing sibling call optimization needs some work, since
3151 structure_value_addr can be allocated on the stack.
3152 It does not seem worth the effort since few optimizable
3153 sibling calls will return a structure. */
3154 if (structure_value_addr
!= NULL_RTX
)
3156 maybe_complain_about_tail_call (exp
, "callee returns a structure");
3160 #ifdef REG_PARM_STACK_SPACE
3161 /* If outgoing reg parm stack space changes, we cannot do sibcall. */
3162 if (OUTGOING_REG_PARM_STACK_SPACE (funtype
)
3163 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl
))
3164 || (reg_parm_stack_space
!= REG_PARM_STACK_SPACE (current_function_decl
)))
3166 maybe_complain_about_tail_call (exp
,
3167 "inconsistent size of stack space"
3168 " allocated for arguments which are"
3169 " passed in registers");
3174 /* Check whether the target is able to optimize the call
3176 if (!targetm
.function_ok_for_sibcall (fndecl
, exp
))
3178 maybe_complain_about_tail_call (exp
,
3179 "target is not able to optimize the"
3180 " call into a sibling call");
3184 /* Functions that do not return exactly once may not be sibcall
3186 if (flags
& ECF_RETURNS_TWICE
)
3188 maybe_complain_about_tail_call (exp
, "callee returns twice");
3191 if (flags
& ECF_NORETURN
)
3193 maybe_complain_about_tail_call (exp
, "callee does not return");
3197 if (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
))))
3199 maybe_complain_about_tail_call (exp
, "volatile function type");
3203 /* If the called function is nested in the current one, it might access
3204 some of the caller's arguments, but could clobber them beforehand if
3205 the argument areas are shared. */
3206 if (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
3208 maybe_complain_about_tail_call (exp
, "nested function");
3212 /* If this function requires more stack slots than the current
3213 function, we cannot change it into a sibling call.
3214 crtl->args.pretend_args_size is not part of the
3215 stack allocated by our caller. */
3216 if (maybe_gt (args_size
.constant
,
3217 crtl
->args
.size
- crtl
->args
.pretend_args_size
))
3219 maybe_complain_about_tail_call (exp
,
3220 "callee required more stack slots"
3221 " than the caller");
3225 /* If the callee pops its own arguments, then it must pop exactly
3226 the same number of arguments as the current function. */
3227 if (maybe_ne (targetm
.calls
.return_pops_args (fndecl
, funtype
,
3228 args_size
.constant
),
3229 targetm
.calls
.return_pops_args (current_function_decl
,
3231 (current_function_decl
),
3234 maybe_complain_about_tail_call (exp
,
3235 "inconsistent number of"
3236 " popped arguments");
3240 if (!lang_hooks
.decls
.ok_for_sibcall (fndecl
))
3242 maybe_complain_about_tail_call (exp
, "frontend does not support"
3247 /* All checks passed. */
3251 /* Update stack alignment when the parameter is passed in the stack
3252 since the outgoing parameter requires extra alignment on the calling
3256 update_stack_alignment_for_call (struct locate_and_pad_arg_data
*locate
)
3258 if (crtl
->stack_alignment_needed
< locate
->boundary
)
3259 crtl
->stack_alignment_needed
= locate
->boundary
;
3260 if (crtl
->preferred_stack_boundary
< locate
->boundary
)
3261 crtl
->preferred_stack_boundary
= locate
->boundary
;
3264 /* Generate all the code for a CALL_EXPR exp
3265 and return an rtx for its value.
3266 Store the value in TARGET (specified as an rtx) if convenient.
3267 If the value is stored in TARGET then TARGET is returned.
3268 If IGNORE is nonzero, then we ignore the value of the function call. */
3271 expand_call (tree exp
, rtx target
, int ignore
)
3273 /* Nonzero if we are currently expanding a call. */
3274 static int currently_expanding_call
= 0;
3276 /* RTX for the function to be called. */
3278 /* Sequence of insns to perform a normal "call". */
3279 rtx_insn
*normal_call_insns
= NULL
;
3280 /* Sequence of insns to perform a tail "call". */
3281 rtx_insn
*tail_call_insns
= NULL
;
3282 /* Data type of the function. */
3284 tree type_arg_types
;
3286 /* Declaration of the function being called,
3287 or 0 if the function is computed (not known by name). */
3289 /* The type of the function being called. */
3291 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
3292 bool must_tail_call
= CALL_EXPR_MUST_TAIL_CALL (exp
);
3295 /* Register in which non-BLKmode value will be returned,
3296 or 0 if no value or if value is BLKmode. */
3298 /* Address where we should return a BLKmode value;
3299 0 if value not BLKmode. */
3300 rtx structure_value_addr
= 0;
3301 /* Nonzero if that address is being passed by treating it as
3302 an extra, implicit first parameter. Otherwise,
3303 it is passed by being copied directly into struct_value_rtx. */
3304 int structure_value_addr_parm
= 0;
3305 /* Holds the value of implicit argument for the struct value. */
3306 tree structure_value_addr_value
= NULL_TREE
;
3307 /* Size of aggregate value wanted, or zero if none wanted
3308 or if we are using the non-reentrant PCC calling convention
3309 or expecting the value in registers. */
3310 poly_int64 struct_value_size
= 0;
3311 /* Nonzero if called function returns an aggregate in memory PCC style,
3312 by returning the address of where to find it. */
3313 int pcc_struct_value
= 0;
3314 rtx struct_value
= 0;
3316 /* Number of actual parameters in this call, including struct value addr. */
3318 /* Number of named args. Args after this are anonymous ones
3319 and they must all go on the stack. */
3321 /* Number of complex actual arguments that need to be split. */
3322 int num_complex_actuals
= 0;
3324 /* Vector of information about each argument.
3325 Arguments are numbered in the order they will be pushed,
3326 not the order they are written. */
3327 struct arg_data
*args
;
3329 /* Total size in bytes of all the stack-parms scanned so far. */
3330 struct args_size args_size
;
3331 struct args_size adjusted_args_size
;
3332 /* Size of arguments before any adjustments (such as rounding). */
3333 poly_int64 unadjusted_args_size
;
3334 /* Data on reg parms scanned so far. */
3335 CUMULATIVE_ARGS args_so_far_v
;
3336 cumulative_args_t args_so_far
;
3337 /* Nonzero if a reg parm has been scanned. */
3339 /* Nonzero if this is an indirect function call. */
3341 /* Nonzero if we must avoid push-insns in the args for this call.
3342 If stack space is allocated for register parameters, but not by the
3343 caller, then it is preallocated in the fixed part of the stack frame.
3344 So the entire argument block must then be preallocated (i.e., we
3345 ignore PUSH_ROUNDING in that case). */
3347 int must_preallocate
= !PUSH_ARGS
;
3349 /* Size of the stack reserved for parameter registers. */
3350 int reg_parm_stack_space
= 0;
3352 /* Address of space preallocated for stack parms
3353 (on machines that lack push insns), or 0 if space not preallocated. */
3356 /* Mask of ECF_ and ERF_ flags. */
3358 int return_flags
= 0;
3359 #ifdef REG_PARM_STACK_SPACE
3360 /* Define the boundary of the register parm stack space that needs to be
3362 int low_to_save
, high_to_save
;
3363 rtx save_area
= 0; /* Place that it is saved */
3366 unsigned int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3367 char *initial_stack_usage_map
= stack_usage_map
;
3368 unsigned HOST_WIDE_INT initial_stack_usage_watermark
= stack_usage_watermark
;
3369 char *stack_usage_map_buf
= NULL
;
3371 poly_int64 old_stack_allocated
;
3373 /* State variables to track stack modifications. */
3374 rtx old_stack_level
= 0;
3375 int old_stack_arg_under_construction
= 0;
3376 poly_int64 old_pending_adj
= 0;
3377 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3379 /* Some stack pointer alterations we make are performed via
3380 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
3381 which we then also need to save/restore along the way. */
3382 poly_int64 old_stack_pointer_delta
= 0;
3385 tree addr
= CALL_EXPR_FN (exp
);
3387 /* The alignment of the stack, in bits. */
3388 unsigned HOST_WIDE_INT preferred_stack_boundary
;
3389 /* The alignment of the stack, in bytes. */
3390 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
3391 /* The static chain value to use for this call. */
3392 rtx static_chain_value
;
3393 /* See if this is "nothrow" function call. */
3394 if (TREE_NOTHROW (exp
))
3395 flags
|= ECF_NOTHROW
;
3397 /* See if we can find a DECL-node for the actual function, and get the
3398 function attributes (flags) from the function decl or type node. */
3399 fndecl
= get_callee_fndecl (exp
);
3402 fntype
= TREE_TYPE (fndecl
);
3403 flags
|= flags_from_decl_or_type (fndecl
);
3404 return_flags
|= decl_return_flags (fndecl
);
3408 fntype
= TREE_TYPE (TREE_TYPE (addr
));
3409 flags
|= flags_from_decl_or_type (fntype
);
3410 if (CALL_EXPR_BY_DESCRIPTOR (exp
))
3411 flags
|= ECF_BY_DESCRIPTOR
;
3413 rettype
= TREE_TYPE (exp
);
3415 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
3417 /* Warn if this value is an aggregate type,
3418 regardless of which calling convention we are using for it. */
3419 if (AGGREGATE_TYPE_P (rettype
))
3420 warning (OPT_Waggregate_return
, "function call has aggregate value");
3422 /* If the result of a non looping pure or const function call is
3423 ignored (or void), and none of its arguments are volatile, we can
3424 avoid expanding the call and just evaluate the arguments for
3426 if ((flags
& (ECF_CONST
| ECF_PURE
))
3427 && (!(flags
& ECF_LOOPING_CONST_OR_PURE
))
3428 && (ignore
|| target
== const0_rtx
3429 || TYPE_MODE (rettype
) == VOIDmode
))
3431 bool volatilep
= false;
3433 call_expr_arg_iterator iter
;
3435 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3436 if (TREE_THIS_VOLATILE (arg
))
3444 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3445 expand_expr (arg
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
3450 #ifdef REG_PARM_STACK_SPACE
3451 reg_parm_stack_space
= REG_PARM_STACK_SPACE (!fndecl
? fntype
: fndecl
);
3454 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
3455 && reg_parm_stack_space
> 0 && PUSH_ARGS
)
3456 must_preallocate
= 1;
3458 /* Set up a place to return a structure. */
3460 /* Cater to broken compilers. */
3461 if (aggregate_value_p (exp
, fntype
))
3463 /* This call returns a big structure. */
3464 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
3466 #ifdef PCC_STATIC_STRUCT_RETURN
3468 pcc_struct_value
= 1;
3470 #else /* not PCC_STATIC_STRUCT_RETURN */
3472 if (!poly_int_tree_p (TYPE_SIZE_UNIT (rettype
), &struct_value_size
))
3473 struct_value_size
= -1;
3475 /* Even if it is semantically safe to use the target as the return
3476 slot, it may be not sufficiently aligned for the return type. */
3477 if (CALL_EXPR_RETURN_SLOT_OPT (exp
)
3480 /* If rettype is addressable, we may not create a temporary.
3481 If target is properly aligned at runtime and the compiler
3482 just doesn't know about it, it will work fine, otherwise it
3484 && (TREE_ADDRESSABLE (rettype
)
3485 || !(MEM_ALIGN (target
) < TYPE_ALIGN (rettype
)
3486 && targetm
.slow_unaligned_access (TYPE_MODE (rettype
),
3487 MEM_ALIGN (target
)))))
3488 structure_value_addr
= XEXP (target
, 0);
3491 /* For variable-sized objects, we must be called with a target
3492 specified. If we were to allocate space on the stack here,
3493 we would have no way of knowing when to free it. */
3494 rtx d
= assign_temp (rettype
, 1, 1);
3495 structure_value_addr
= XEXP (d
, 0);
3499 #endif /* not PCC_STATIC_STRUCT_RETURN */
3502 /* Figure out the amount to which the stack should be aligned. */
3503 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3506 struct cgraph_rtl_info
*i
= cgraph_node::rtl_info (fndecl
);
3507 /* Without automatic stack alignment, we can't increase preferred
3508 stack boundary. With automatic stack alignment, it is
3509 unnecessary since unless we can guarantee that all callers will
3510 align the outgoing stack properly, callee has to align its
3513 && i
->preferred_incoming_stack_boundary
3514 && i
->preferred_incoming_stack_boundary
< preferred_stack_boundary
)
3515 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
3518 /* Operand 0 is a pointer-to-function; get the type of the function. */
3519 funtype
= TREE_TYPE (addr
);
3520 gcc_assert (POINTER_TYPE_P (funtype
));
3521 funtype
= TREE_TYPE (funtype
);
3523 /* Count whether there are actual complex arguments that need to be split
3524 into their real and imaginary parts. Munge the type_arg_types
3525 appropriately here as well. */
3526 if (targetm
.calls
.split_complex_arg
)
3528 call_expr_arg_iterator iter
;
3530 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3532 tree type
= TREE_TYPE (arg
);
3533 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
3534 && targetm
.calls
.split_complex_arg (type
))
3535 num_complex_actuals
++;
3537 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
3540 type_arg_types
= TYPE_ARG_TYPES (funtype
);
3542 if (flags
& ECF_MAY_BE_ALLOCA
)
3543 cfun
->calls_alloca
= 1;
3545 /* If struct_value_rtx is 0, it means pass the address
3546 as if it were an extra parameter. Put the argument expression
3547 in structure_value_addr_value. */
3548 if (structure_value_addr
&& struct_value
== 0)
3550 /* If structure_value_addr is a REG other than
3551 virtual_outgoing_args_rtx, we can use always use it. If it
3552 is not a REG, we must always copy it into a register.
3553 If it is virtual_outgoing_args_rtx, we must copy it to another
3554 register in some cases. */
3555 rtx temp
= (!REG_P (structure_value_addr
)
3556 || (ACCUMULATE_OUTGOING_ARGS
3557 && stack_arg_under_construction
3558 && structure_value_addr
== virtual_outgoing_args_rtx
)
3559 ? copy_addr_to_reg (convert_memory_address
3560 (Pmode
, structure_value_addr
))
3561 : structure_value_addr
);
3563 structure_value_addr_value
=
3564 make_tree (build_pointer_type (TREE_TYPE (funtype
)), temp
);
3565 structure_value_addr_parm
= 1;
3568 /* Count the arguments and set NUM_ACTUALS. */
3570 call_expr_nargs (exp
) + num_complex_actuals
+ structure_value_addr_parm
;
3572 /* Compute number of named args.
3573 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
3575 if (type_arg_types
!= 0)
3577 = (list_length (type_arg_types
)
3578 /* Count the struct value address, if it is passed as a parm. */
3579 + structure_value_addr_parm
);
3581 /* If we know nothing, treat all args as named. */
3582 n_named_args
= num_actuals
;
3584 /* Start updating where the next arg would go.
3586 On some machines (such as the PA) indirect calls have a different
3587 calling convention than normal calls. The fourth argument in
3588 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
3590 INIT_CUMULATIVE_ARGS (args_so_far_v
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
3591 args_so_far
= pack_cumulative_args (&args_so_far_v
);
3593 /* Now possibly adjust the number of named args.
3594 Normally, don't include the last named arg if anonymous args follow.
3595 We do include the last named arg if
3596 targetm.calls.strict_argument_naming() returns nonzero.
3597 (If no anonymous args follow, the result of list_length is actually
3598 one too large. This is harmless.)
3600 If targetm.calls.pretend_outgoing_varargs_named() returns
3601 nonzero, and targetm.calls.strict_argument_naming() returns zero,
3602 this machine will be able to place unnamed args that were passed
3603 in registers into the stack. So treat all args as named. This
3604 allows the insns emitting for a specific argument list to be
3605 independent of the function declaration.
3607 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
3608 we do not have any reliable way to pass unnamed args in
3609 registers, so we must force them into memory. */
3611 if (type_arg_types
!= 0
3612 && targetm
.calls
.strict_argument_naming (args_so_far
))
3614 else if (type_arg_types
!= 0
3615 && ! targetm
.calls
.pretend_outgoing_varargs_named (args_so_far
))
3616 /* Don't include the last named arg. */
3619 /* Treat all args as named. */
3620 n_named_args
= num_actuals
;
3622 /* Make a vector to hold all the information about each arg. */
3623 args
= XCNEWVEC (struct arg_data
, num_actuals
);
3625 /* Build up entries in the ARGS array, compute the size of the
3626 arguments into ARGS_SIZE, etc. */
3627 initialize_argument_information (num_actuals
, args
, &args_size
,
3629 structure_value_addr_value
, fndecl
, fntype
,
3630 args_so_far
, reg_parm_stack_space
,
3631 &old_stack_level
, &old_pending_adj
,
3632 &must_preallocate
, &flags
,
3633 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
3636 must_preallocate
= 1;
3638 /* Now make final decision about preallocating stack space. */
3639 must_preallocate
= finalize_must_preallocate (must_preallocate
,
3643 /* If the structure value address will reference the stack pointer, we
3644 must stabilize it. We don't need to do this if we know that we are
3645 not going to adjust the stack pointer in processing this call. */
3647 if (structure_value_addr
3648 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
3649 || reg_mentioned_p (virtual_outgoing_args_rtx
,
3650 structure_value_addr
))
3652 || (!ACCUMULATE_OUTGOING_ARGS
3653 && maybe_ne (args_size
.constant
, 0))))
3654 structure_value_addr
= copy_to_reg (structure_value_addr
);
3656 /* Tail calls can make things harder to debug, and we've traditionally
3657 pushed these optimizations into -O2. Don't try if we're already
3658 expanding a call, as that means we're an argument. Don't try if
3659 there's cleanups, as we know there's code to follow the call. */
3660 if (currently_expanding_call
++ != 0
3661 || (!flag_optimize_sibling_calls
&& !CALL_FROM_THUNK_P (exp
))
3663 || dbg_cnt (tail_call
) == false)
3666 /* Workaround buggy C/C++ wrappers around Fortran routines with
3667 character(len=constant) arguments if the hidden string length arguments
3668 are passed on the stack; if the callers forget to pass those arguments,
3669 attempting to tail call in such routines leads to stack corruption.
3670 Avoid tail calls in functions where at least one such hidden string
3671 length argument is passed (partially or fully) on the stack in the
3672 caller and the callee needs to pass any arguments on the stack.
3674 if (try_tail_call
&& maybe_ne (args_size
.constant
, 0))
3675 for (tree arg
= DECL_ARGUMENTS (current_function_decl
);
3676 arg
; arg
= DECL_CHAIN (arg
))
3677 if (DECL_HIDDEN_STRING_LENGTH (arg
) && DECL_INCOMING_RTL (arg
))
3679 subrtx_iterator::array_type array
;
3680 FOR_EACH_SUBRTX (iter
, array
, DECL_INCOMING_RTL (arg
), NONCONST
)
3688 /* If the user has marked the function as requiring tail-call
3689 optimization, attempt it. */
3693 /* Rest of purposes for tail call optimizations to fail. */
3695 try_tail_call
= can_implement_as_sibling_call_p (exp
,
3696 structure_value_addr
,
3698 reg_parm_stack_space
,
3700 flags
, addr
, args_size
);
3702 /* Check if caller and callee disagree in promotion of function
3706 machine_mode caller_mode
, caller_promoted_mode
;
3707 machine_mode callee_mode
, callee_promoted_mode
;
3708 int caller_unsignedp
, callee_unsignedp
;
3709 tree caller_res
= DECL_RESULT (current_function_decl
);
3711 caller_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (caller_res
));
3712 caller_mode
= DECL_MODE (caller_res
);
3713 callee_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (funtype
));
3714 callee_mode
= TYPE_MODE (TREE_TYPE (funtype
));
3715 caller_promoted_mode
3716 = promote_function_mode (TREE_TYPE (caller_res
), caller_mode
,
3718 TREE_TYPE (current_function_decl
), 1);
3719 callee_promoted_mode
3720 = promote_function_mode (TREE_TYPE (funtype
), callee_mode
,
3723 if (caller_mode
!= VOIDmode
3724 && (caller_promoted_mode
!= callee_promoted_mode
3725 || ((caller_mode
!= caller_promoted_mode
3726 || callee_mode
!= callee_promoted_mode
)
3727 && (caller_unsignedp
!= callee_unsignedp
3728 || partial_subreg_p (caller_mode
, callee_mode
)))))
3731 maybe_complain_about_tail_call (exp
,
3732 "caller and callee disagree in"
3733 " promotion of function"
3738 /* Ensure current function's preferred stack boundary is at least
3739 what we need. Stack alignment may also increase preferred stack
3741 for (i
= 0; i
< num_actuals
; i
++)
3742 if (reg_parm_stack_space
> 0
3744 || args
[i
].partial
!= 0
3745 || args
[i
].pass_on_stack
)
3746 update_stack_alignment_for_call (&args
[i
].locate
);
3747 if (crtl
->preferred_stack_boundary
< preferred_stack_boundary
)
3748 crtl
->preferred_stack_boundary
= preferred_stack_boundary
;
3750 preferred_stack_boundary
= crtl
->preferred_stack_boundary
;
3752 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
3754 /* We want to make two insn chains; one for a sibling call, the other
3755 for a normal call. We will select one of the two chains after
3756 initial RTL generation is complete. */
3757 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
3759 int sibcall_failure
= 0;
3760 /* We want to emit any pending stack adjustments before the tail
3761 recursion "call". That way we know any adjustment after the tail
3762 recursion call can be ignored if we indeed use the tail
3764 saved_pending_stack_adjust save
;
3765 rtx_insn
*insns
, *before_call
, *after_args
;
3770 /* State variables we need to save and restore between
3772 save_pending_stack_adjust (&save
);
3775 flags
&= ~ECF_SIBCALL
;
3777 flags
|= ECF_SIBCALL
;
3779 /* Other state variables that we must reinitialize each time
3780 through the loop (that are not initialized by the loop itself). */
3784 /* Start a new sequence for the normal call case.
3786 From this point on, if the sibling call fails, we want to set
3787 sibcall_failure instead of continuing the loop. */
3790 /* Don't let pending stack adjusts add up to too much.
3791 Also, do all pending adjustments now if there is any chance
3792 this might be a call to alloca or if we are expanding a sibling
3794 Also do the adjustments before a throwing call, otherwise
3795 exception handling can fail; PR 19225. */
3796 if (maybe_ge (pending_stack_adjust
, 32)
3797 || (maybe_ne (pending_stack_adjust
, 0)
3798 && (flags
& ECF_MAY_BE_ALLOCA
))
3799 || (maybe_ne (pending_stack_adjust
, 0)
3800 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
3802 do_pending_stack_adjust ();
3804 /* Precompute any arguments as needed. */
3806 precompute_arguments (num_actuals
, args
);
3808 /* Now we are about to start emitting insns that can be deleted
3809 if a libcall is deleted. */
3810 if (pass
&& (flags
& ECF_MALLOC
))
3814 && crtl
->stack_protect_guard
3815 && targetm
.stack_protect_runtime_enabled_p ())
3816 stack_protect_epilogue ();
3818 adjusted_args_size
= args_size
;
3819 /* Compute the actual size of the argument block required. The variable
3820 and constant sizes must be combined, the size may have to be rounded,
3821 and there may be a minimum required size. When generating a sibcall
3822 pattern, do not round up, since we'll be re-using whatever space our
3824 unadjusted_args_size
3825 = compute_argument_block_size (reg_parm_stack_space
,
3826 &adjusted_args_size
,
3829 : preferred_stack_boundary
));
3831 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
3833 /* The argument block when performing a sibling call is the
3834 incoming argument block. */
3837 argblock
= crtl
->args
.internal_arg_pointer
;
3838 if (STACK_GROWS_DOWNWARD
)
3840 = plus_constant (Pmode
, argblock
, crtl
->args
.pretend_args_size
);
3843 = plus_constant (Pmode
, argblock
, -crtl
->args
.pretend_args_size
);
3845 HOST_WIDE_INT map_size
= constant_lower_bound (args_size
.constant
);
3846 stored_args_map
= sbitmap_alloc (map_size
);
3847 bitmap_clear (stored_args_map
);
3848 stored_args_watermark
= HOST_WIDE_INT_M1U
;
3851 /* If we have no actual push instructions, or shouldn't use them,
3852 make space for all args right now. */
3853 else if (adjusted_args_size
.var
!= 0)
3855 if (old_stack_level
== 0)
3857 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
3858 old_stack_pointer_delta
= stack_pointer_delta
;
3859 old_pending_adj
= pending_stack_adjust
;
3860 pending_stack_adjust
= 0;
3861 /* stack_arg_under_construction says whether a stack arg is
3862 being constructed at the old stack level. Pushing the stack
3863 gets a clean outgoing argument block. */
3864 old_stack_arg_under_construction
= stack_arg_under_construction
;
3865 stack_arg_under_construction
= 0;
3867 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
3868 if (flag_stack_usage_info
)
3869 current_function_has_unbounded_dynamic_stack_size
= 1;
3873 /* Note that we must go through the motions of allocating an argument
3874 block even if the size is zero because we may be storing args
3875 in the area reserved for register arguments, which may be part of
3878 poly_int64 needed
= adjusted_args_size
.constant
;
3880 /* Store the maximum argument space used. It will be pushed by
3881 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
3884 crtl
->outgoing_args_size
= upper_bound (crtl
->outgoing_args_size
,
3887 if (must_preallocate
)
3889 if (ACCUMULATE_OUTGOING_ARGS
)
3891 /* Since the stack pointer will never be pushed, it is
3892 possible for the evaluation of a parm to clobber
3893 something we have already written to the stack.
3894 Since most function calls on RISC machines do not use
3895 the stack, this is uncommon, but must work correctly.
3897 Therefore, we save any area of the stack that was already
3898 written and that we are using. Here we set up to do this
3899 by making a new stack usage map from the old one. The
3900 actual save will be done by store_one_arg.
3902 Another approach might be to try to reorder the argument
3903 evaluations to avoid this conflicting stack usage. */
3905 /* Since we will be writing into the entire argument area,
3906 the map must be allocated for its entire size, not just
3907 the part that is the responsibility of the caller. */
3908 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3909 needed
+= reg_parm_stack_space
;
3911 poly_int64 limit
= needed
;
3912 if (ARGS_GROW_DOWNWARD
)
3915 /* For polynomial sizes, this is the maximum possible
3916 size needed for arguments with a constant size
3918 HOST_WIDE_INT const_limit
= constant_lower_bound (limit
);
3919 highest_outgoing_arg_in_use
3920 = MAX (initial_highest_arg_in_use
, const_limit
);
3922 free (stack_usage_map_buf
);
3923 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
3924 stack_usage_map
= stack_usage_map_buf
;
3926 if (initial_highest_arg_in_use
)
3927 memcpy (stack_usage_map
, initial_stack_usage_map
,
3928 initial_highest_arg_in_use
);
3930 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3931 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3932 (highest_outgoing_arg_in_use
3933 - initial_highest_arg_in_use
));
3936 /* The address of the outgoing argument list must not be
3937 copied to a register here, because argblock would be left
3938 pointing to the wrong place after the call to
3939 allocate_dynamic_stack_space below. */
3941 argblock
= virtual_outgoing_args_rtx
;
3945 /* Try to reuse some or all of the pending_stack_adjust
3946 to get this space. */
3947 if (inhibit_defer_pop
== 0
3948 && (combine_pending_stack_adjustment_and_call
3950 unadjusted_args_size
,
3951 &adjusted_args_size
,
3952 preferred_unit_stack_boundary
)))
3954 /* combine_pending_stack_adjustment_and_call computes
3955 an adjustment before the arguments are allocated.
3956 Account for them and see whether or not the stack
3957 needs to go up or down. */
3958 needed
= unadjusted_args_size
- needed
;
3961 combine_pending_stack_adjustment_and_call. */
3962 gcc_checking_assert (ordered_p (needed
, 0));
3963 if (maybe_lt (needed
, 0))
3965 /* We're releasing stack space. */
3966 /* ??? We can avoid any adjustment at all if we're
3967 already aligned. FIXME. */
3968 pending_stack_adjust
= -needed
;
3969 do_pending_stack_adjust ();
3973 /* We need to allocate space. We'll do that in
3974 push_block below. */
3975 pending_stack_adjust
= 0;
3978 /* Special case this because overhead of `push_block' in
3979 this case is non-trivial. */
3980 if (known_eq (needed
, 0))
3981 argblock
= virtual_outgoing_args_rtx
;
3984 rtx needed_rtx
= gen_int_mode (needed
, Pmode
);
3985 argblock
= push_block (needed_rtx
, 0, 0);
3986 if (ARGS_GROW_DOWNWARD
)
3987 argblock
= plus_constant (Pmode
, argblock
, needed
);
3990 /* We only really need to call `copy_to_reg' in the case
3991 where push insns are going to be used to pass ARGBLOCK
3992 to a function call in ARGS. In that case, the stack
3993 pointer changes value from the allocation point to the
3994 call point, and hence the value of
3995 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3996 as well always do it. */
3997 argblock
= copy_to_reg (argblock
);
4002 if (ACCUMULATE_OUTGOING_ARGS
)
4004 /* The save/restore code in store_one_arg handles all
4005 cases except one: a constructor call (including a C
4006 function returning a BLKmode struct) to initialize
4008 if (stack_arg_under_construction
)
4012 (adjusted_args_size
.constant
4013 + (OUTGOING_REG_PARM_STACK_SPACE (!fndecl
? fntype
4014 : TREE_TYPE (fndecl
))
4015 ? 0 : reg_parm_stack_space
), Pmode
));
4016 if (old_stack_level
== 0)
4018 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
4019 old_stack_pointer_delta
= stack_pointer_delta
;
4020 old_pending_adj
= pending_stack_adjust
;
4021 pending_stack_adjust
= 0;
4022 /* stack_arg_under_construction says whether a stack
4023 arg is being constructed at the old stack level.
4024 Pushing the stack gets a clean outgoing argument
4026 old_stack_arg_under_construction
4027 = stack_arg_under_construction
;
4028 stack_arg_under_construction
= 0;
4029 /* Make a new map for the new argument list. */
4030 free (stack_usage_map_buf
);
4031 stack_usage_map_buf
= XCNEWVEC (char, highest_outgoing_arg_in_use
);
4032 stack_usage_map
= stack_usage_map_buf
;
4033 highest_outgoing_arg_in_use
= 0;
4034 stack_usage_watermark
= HOST_WIDE_INT_M1U
;
4036 /* We can pass TRUE as the 4th argument because we just
4037 saved the stack pointer and will restore it right after
4039 allocate_dynamic_stack_space (push_size
, 0, BIGGEST_ALIGNMENT
,
4043 /* If argument evaluation might modify the stack pointer,
4044 copy the address of the argument list to a register. */
4045 for (i
= 0; i
< num_actuals
; i
++)
4046 if (args
[i
].pass_on_stack
)
4048 argblock
= copy_addr_to_reg (argblock
);
4053 compute_argument_addresses (args
, argblock
, num_actuals
);
4055 /* Stack is properly aligned, pops can't safely be deferred during
4056 the evaluation of the arguments. */
4059 /* Precompute all register parameters. It isn't safe to compute
4060 anything once we have started filling any specific hard regs.
4061 TLS symbols sometimes need a call to resolve. Precompute
4062 register parameters before any stack pointer manipulation
4063 to avoid unaligned stack in the called function. */
4064 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
4068 /* Perform stack alignment before the first push (the last arg). */
4070 && maybe_gt (adjusted_args_size
.constant
, reg_parm_stack_space
)
4071 && maybe_ne (adjusted_args_size
.constant
, unadjusted_args_size
))
4073 /* When the stack adjustment is pending, we get better code
4074 by combining the adjustments. */
4075 if (maybe_ne (pending_stack_adjust
, 0)
4076 && ! inhibit_defer_pop
4077 && (combine_pending_stack_adjustment_and_call
4078 (&pending_stack_adjust
,
4079 unadjusted_args_size
,
4080 &adjusted_args_size
,
4081 preferred_unit_stack_boundary
)))
4082 do_pending_stack_adjust ();
4083 else if (argblock
== 0)
4084 anti_adjust_stack (gen_int_mode (adjusted_args_size
.constant
4085 - unadjusted_args_size
,
4088 /* Now that the stack is properly aligned, pops can't safely
4089 be deferred during the evaluation of the arguments. */
4092 /* Record the maximum pushed stack space size. We need to delay
4093 doing it this far to take into account the optimization done
4094 by combine_pending_stack_adjustment_and_call. */
4095 if (flag_stack_usage_info
4096 && !ACCUMULATE_OUTGOING_ARGS
4098 && adjusted_args_size
.var
== 0)
4100 poly_int64 pushed
= (adjusted_args_size
.constant
4101 + pending_stack_adjust
);
4102 current_function_pushed_stack_size
4103 = upper_bound (current_function_pushed_stack_size
, pushed
);
4106 funexp
= rtx_for_function_call (fndecl
, addr
);
4108 if (CALL_EXPR_STATIC_CHAIN (exp
))
4109 static_chain_value
= expand_normal (CALL_EXPR_STATIC_CHAIN (exp
));
4111 static_chain_value
= 0;
4113 #ifdef REG_PARM_STACK_SPACE
4114 /* Save the fixed argument area if it's part of the caller's frame and
4115 is clobbered by argument setup for this call. */
4116 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
4117 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
4118 &low_to_save
, &high_to_save
);
4121 /* Now store (and compute if necessary) all non-register parms.
4122 These come before register parms, since they can require block-moves,
4123 which could clobber the registers used for register parms.
4124 Parms which have partial registers are not stored here,
4125 but we do preallocate space here if they want that. */
4127 for (i
= 0; i
< num_actuals
; i
++)
4129 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
4131 rtx_insn
*before_arg
= get_last_insn ();
4133 /* We don't allow passing huge (> 2^30 B) arguments
4134 by value. It would cause an overflow later on. */
4135 if (constant_lower_bound (adjusted_args_size
.constant
)
4136 >= (1 << (HOST_BITS_PER_INT
- 2)))
4138 sorry ("passing too large argument on stack");
4142 if (store_one_arg (&args
[i
], argblock
, flags
,
4143 adjusted_args_size
.var
!= 0,
4144 reg_parm_stack_space
)
4146 && check_sibcall_argument_overlap (before_arg
,
4148 sibcall_failure
= 1;
4153 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
4154 gen_rtx_USE (VOIDmode
, args
[i
].stack
),
4158 /* If we have a parm that is passed in registers but not in memory
4159 and whose alignment does not permit a direct copy into registers,
4160 make a group of pseudos that correspond to each register that we
4162 if (STRICT_ALIGNMENT
)
4163 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
4165 /* Now store any partially-in-registers parm.
4166 This is the last place a block-move can happen. */
4168 for (i
= 0; i
< num_actuals
; i
++)
4169 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
4171 rtx_insn
*before_arg
= get_last_insn ();
4173 /* On targets with weird calling conventions (e.g. PA) it's
4174 hard to ensure that all cases of argument overlap between
4175 stack and registers work. Play it safe and bail out. */
4176 if (ARGS_GROW_DOWNWARD
&& !STACK_GROWS_DOWNWARD
)
4178 sibcall_failure
= 1;
4182 if (store_one_arg (&args
[i
], argblock
, flags
,
4183 adjusted_args_size
.var
!= 0,
4184 reg_parm_stack_space
)
4186 && check_sibcall_argument_overlap (before_arg
,
4188 sibcall_failure
= 1;
4191 bool any_regs
= false;
4192 for (i
= 0; i
< num_actuals
; i
++)
4193 if (args
[i
].reg
!= NULL_RTX
)
4196 targetm
.calls
.call_args (args
[i
].reg
, funtype
);
4199 targetm
.calls
.call_args (pc_rtx
, funtype
);
4201 /* Figure out the register where the value, if any, will come back. */
4203 if (TYPE_MODE (rettype
) != VOIDmode
4204 && ! structure_value_addr
)
4206 if (pcc_struct_value
)
4207 valreg
= hard_function_value (build_pointer_type (rettype
),
4208 fndecl
, NULL
, (pass
== 0));
4210 valreg
= hard_function_value (rettype
, fndecl
, fntype
,
4213 /* If VALREG is a PARALLEL whose first member has a zero
4214 offset, use that. This is for targets such as m68k that
4215 return the same value in multiple places. */
4216 if (GET_CODE (valreg
) == PARALLEL
)
4218 rtx elem
= XVECEXP (valreg
, 0, 0);
4219 rtx where
= XEXP (elem
, 0);
4220 rtx offset
= XEXP (elem
, 1);
4221 if (offset
== const0_rtx
4222 && GET_MODE (where
) == GET_MODE (valreg
))
4227 /* If register arguments require space on the stack and stack space
4228 was not preallocated, allocate stack space here for arguments
4229 passed in registers. */
4230 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
4231 && !ACCUMULATE_OUTGOING_ARGS
4232 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
4233 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
4235 /* Pass the function the address in which to return a
4237 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
4239 structure_value_addr
4240 = convert_memory_address (Pmode
, structure_value_addr
);
4241 emit_move_insn (struct_value
,
4243 force_operand (structure_value_addr
,
4246 if (REG_P (struct_value
))
4247 use_reg (&call_fusage
, struct_value
);
4250 after_args
= get_last_insn ();
4251 funexp
= prepare_call_address (fndecl
? fndecl
: fntype
, funexp
,
4252 static_chain_value
, &call_fusage
,
4253 reg_parm_seen
, flags
);
4255 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
4256 pass
== 0, &sibcall_failure
);
4258 /* Save a pointer to the last insn before the call, so that we can
4259 later safely search backwards to find the CALL_INSN. */
4260 before_call
= get_last_insn ();
4262 /* Set up next argument register. For sibling calls on machines
4263 with register windows this should be the incoming register. */
4265 next_arg_reg
= targetm
.calls
.function_incoming_arg
4266 (args_so_far
, function_arg_info::end_marker ());
4268 next_arg_reg
= targetm
.calls
.function_arg
4269 (args_so_far
, function_arg_info::end_marker ());
4271 if (pass
== 1 && (return_flags
& ERF_RETURNS_ARG
))
4273 int arg_nr
= return_flags
& ERF_RETURN_ARG_MASK
;
4274 arg_nr
= num_actuals
- arg_nr
- 1;
4276 && arg_nr
< num_actuals
4280 && GET_MODE (args
[arg_nr
].reg
) == GET_MODE (valreg
))
4282 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args
[arg_nr
].tree_value
)),
4283 gen_rtx_SET (valreg
, args
[arg_nr
].reg
),
4286 /* All arguments and registers used for the call must be set up by
4289 /* Stack must be properly aligned now. */
4291 || multiple_p (stack_pointer_delta
,
4292 preferred_unit_stack_boundary
));
4294 /* Generate the actual call instruction. */
4295 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
4296 adjusted_args_size
.constant
, struct_value_size
,
4297 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
4298 flags
, args_so_far
);
4302 rtx_call_insn
*last
;
4303 rtx datum
= NULL_RTX
;
4304 if (fndecl
!= NULL_TREE
)
4306 datum
= XEXP (DECL_RTL (fndecl
), 0);
4307 gcc_assert (datum
!= NULL_RTX
4308 && GET_CODE (datum
) == SYMBOL_REF
);
4310 last
= last_call_insn ();
4311 add_reg_note (last
, REG_CALL_DECL
, datum
);
4314 /* If the call setup or the call itself overlaps with anything
4315 of the argument setup we probably clobbered our call address.
4316 In that case we can't do sibcalls. */
4318 && check_sibcall_argument_overlap (after_args
, 0, 0))
4319 sibcall_failure
= 1;
4321 /* If a non-BLKmode value is returned at the most significant end
4322 of a register, shift the register right by the appropriate amount
4323 and update VALREG accordingly. BLKmode values are handled by the
4324 group load/store machinery below. */
4325 if (!structure_value_addr
4326 && !pcc_struct_value
4327 && TYPE_MODE (rettype
) != VOIDmode
4328 && TYPE_MODE (rettype
) != BLKmode
4330 && targetm
.calls
.return_in_msb (rettype
))
4332 if (shift_return_value (TYPE_MODE (rettype
), false, valreg
))
4333 sibcall_failure
= 1;
4334 valreg
= gen_rtx_REG (TYPE_MODE (rettype
), REGNO (valreg
));
4337 if (pass
&& (flags
& ECF_MALLOC
))
4339 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
4340 rtx_insn
*last
, *insns
;
4342 /* The return value from a malloc-like function is a pointer. */
4343 if (TREE_CODE (rettype
) == POINTER_TYPE
)
4344 mark_reg_pointer (temp
, MALLOC_ABI_ALIGNMENT
);
4346 emit_move_insn (temp
, valreg
);
4348 /* The return value from a malloc-like function cannot alias
4350 last
= get_last_insn ();
4351 add_reg_note (last
, REG_NOALIAS
, temp
);
4353 /* Write out the sequence. */
4354 insns
= get_insns ();
4360 /* For calls to `setjmp', etc., inform
4361 function.c:setjmp_warnings that it should complain if
4362 nonvolatile values are live. For functions that cannot
4363 return, inform flow that control does not fall through. */
4365 if ((flags
& ECF_NORETURN
) || pass
== 0)
4367 /* The barrier must be emitted
4368 immediately after the CALL_INSN. Some ports emit more
4369 than just a CALL_INSN above, so we must search for it here. */
4371 rtx_insn
*last
= get_last_insn ();
4372 while (!CALL_P (last
))
4374 last
= PREV_INSN (last
);
4375 /* There was no CALL_INSN? */
4376 gcc_assert (last
!= before_call
);
4379 emit_barrier_after (last
);
4381 /* Stack adjustments after a noreturn call are dead code.
4382 However when NO_DEFER_POP is in effect, we must preserve
4383 stack_pointer_delta. */
4384 if (inhibit_defer_pop
== 0)
4386 stack_pointer_delta
= old_stack_allocated
;
4387 pending_stack_adjust
= 0;
4391 /* If value type not void, return an rtx for the value. */
4393 if (TYPE_MODE (rettype
) == VOIDmode
4395 target
= const0_rtx
;
4396 else if (structure_value_addr
)
4398 if (target
== 0 || !MEM_P (target
))
4401 = gen_rtx_MEM (TYPE_MODE (rettype
),
4402 memory_address (TYPE_MODE (rettype
),
4403 structure_value_addr
));
4404 set_mem_attributes (target
, rettype
, 1);
4407 else if (pcc_struct_value
)
4409 /* This is the special C++ case where we need to
4410 know what the true target was. We take care to
4411 never use this value more than once in one expression. */
4412 target
= gen_rtx_MEM (TYPE_MODE (rettype
),
4413 copy_to_reg (valreg
));
4414 set_mem_attributes (target
, rettype
, 1);
4416 /* Handle calls that return values in multiple non-contiguous locations.
4417 The Irix 6 ABI has examples of this. */
4418 else if (GET_CODE (valreg
) == PARALLEL
)
4421 target
= emit_group_move_into_temps (valreg
);
4422 else if (rtx_equal_p (target
, valreg
))
4424 else if (GET_CODE (target
) == PARALLEL
)
4425 /* Handle the result of a emit_group_move_into_temps
4426 call in the previous pass. */
4427 emit_group_move (target
, valreg
);
4429 emit_group_store (target
, valreg
, rettype
,
4430 int_size_in_bytes (rettype
));
4433 && GET_MODE (target
) == TYPE_MODE (rettype
)
4434 && GET_MODE (target
) == GET_MODE (valreg
))
4436 bool may_overlap
= false;
4438 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
4439 reg to a plain register. */
4440 if (!REG_P (target
) || HARD_REGISTER_P (target
))
4441 valreg
= avoid_likely_spilled_reg (valreg
);
4443 /* If TARGET is a MEM in the argument area, and we have
4444 saved part of the argument area, then we can't store
4445 directly into TARGET as it may get overwritten when we
4446 restore the argument save area below. Don't work too
4447 hard though and simply force TARGET to a register if it
4448 is a MEM; the optimizer is quite likely to sort it out. */
4449 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
4450 for (i
= 0; i
< num_actuals
; i
++)
4451 if (args
[i
].save_area
)
4458 target
= copy_to_reg (valreg
);
4461 /* TARGET and VALREG cannot be equal at this point
4462 because the latter would not have
4463 REG_FUNCTION_VALUE_P true, while the former would if
4464 it were referring to the same register.
4466 If they refer to the same register, this move will be
4467 a no-op, except when function inlining is being
4469 emit_move_insn (target
, valreg
);
4471 /* If we are setting a MEM, this code must be executed.
4472 Since it is emitted after the call insn, sibcall
4473 optimization cannot be performed in that case. */
4475 sibcall_failure
= 1;
4479 target
= copy_to_reg (avoid_likely_spilled_reg (valreg
));
4481 /* If we promoted this return value, make the proper SUBREG.
4482 TARGET might be const0_rtx here, so be careful. */
4484 && TYPE_MODE (rettype
) != BLKmode
4485 && GET_MODE (target
) != TYPE_MODE (rettype
))
4487 tree type
= rettype
;
4488 int unsignedp
= TYPE_UNSIGNED (type
);
4491 /* Ensure we promote as expected, and get the new unsignedness. */
4492 pmode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
4494 gcc_assert (GET_MODE (target
) == pmode
);
4496 poly_uint64 offset
= subreg_lowpart_offset (TYPE_MODE (type
),
4498 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
4499 SUBREG_PROMOTED_VAR_P (target
) = 1;
4500 SUBREG_PROMOTED_SET (target
, unsignedp
);
4503 /* If size of args is variable or this was a constructor call for a stack
4504 argument, restore saved stack-pointer value. */
4506 if (old_stack_level
)
4508 rtx_insn
*prev
= get_last_insn ();
4510 emit_stack_restore (SAVE_BLOCK
, old_stack_level
);
4511 stack_pointer_delta
= old_stack_pointer_delta
;
4513 fixup_args_size_notes (prev
, get_last_insn (), stack_pointer_delta
);
4515 pending_stack_adjust
= old_pending_adj
;
4516 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
4517 stack_arg_under_construction
= old_stack_arg_under_construction
;
4518 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4519 stack_usage_map
= initial_stack_usage_map
;
4520 stack_usage_watermark
= initial_stack_usage_watermark
;
4521 sibcall_failure
= 1;
4523 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
4525 #ifdef REG_PARM_STACK_SPACE
4527 restore_fixed_argument_area (save_area
, argblock
,
4528 high_to_save
, low_to_save
);
4531 /* If we saved any argument areas, restore them. */
4532 for (i
= 0; i
< num_actuals
; i
++)
4533 if (args
[i
].save_area
)
4535 machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
4537 = gen_rtx_MEM (save_mode
,
4538 memory_address (save_mode
,
4539 XEXP (args
[i
].stack_slot
, 0)));
4541 if (save_mode
!= BLKmode
)
4542 emit_move_insn (stack_area
, args
[i
].save_area
);
4544 emit_block_move (stack_area
, args
[i
].save_area
,
4546 (args
[i
].locate
.size
.constant
, Pmode
)),
4547 BLOCK_OP_CALL_PARM
);
4550 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4551 stack_usage_map
= initial_stack_usage_map
;
4552 stack_usage_watermark
= initial_stack_usage_watermark
;
4555 /* If this was alloca, record the new stack level. */
4556 if (flags
& ECF_MAY_BE_ALLOCA
)
4557 record_new_stack_level ();
4559 /* Free up storage we no longer need. */
4560 for (i
= 0; i
< num_actuals
; ++i
)
4561 free (args
[i
].aligned_regs
);
4563 targetm
.calls
.end_call_args ();
4565 insns
= get_insns ();
4570 tail_call_insns
= insns
;
4572 /* Restore the pending stack adjustment now that we have
4573 finished generating the sibling call sequence. */
4575 restore_pending_stack_adjust (&save
);
4577 /* Prepare arg structure for next iteration. */
4578 for (i
= 0; i
< num_actuals
; i
++)
4581 args
[i
].aligned_regs
= 0;
4585 sbitmap_free (stored_args_map
);
4586 internal_arg_pointer_exp_state
.scan_start
= NULL
;
4587 internal_arg_pointer_exp_state
.cache
.release ();
4591 normal_call_insns
= insns
;
4593 /* Verify that we've deallocated all the stack we used. */
4594 gcc_assert ((flags
& ECF_NORETURN
)
4595 || known_eq (old_stack_allocated
,
4597 - pending_stack_adjust
));
4600 /* If something prevents making this a sibling call,
4601 zero out the sequence. */
4602 if (sibcall_failure
)
4603 tail_call_insns
= NULL
;
4608 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
4609 arguments too, as argument area is now clobbered by the call. */
4610 if (tail_call_insns
)
4612 emit_insn (tail_call_insns
);
4613 crtl
->tail_call_emit
= true;
4617 emit_insn (normal_call_insns
);
4619 /* Ideally we'd emit a message for all of the ways that it could
4621 maybe_complain_about_tail_call (exp
, "tail call production failed");
4624 currently_expanding_call
--;
4626 free (stack_usage_map_buf
);
4631 /* A sibling call sequence invalidates any REG_EQUIV notes made for
4632 this function's incoming arguments.
4634 At the start of RTL generation we know the only REG_EQUIV notes
4635 in the rtl chain are those for incoming arguments, so we can look
4636 for REG_EQUIV notes between the start of the function and the
4637 NOTE_INSN_FUNCTION_BEG.
4639 This is (slight) overkill. We could keep track of the highest
4640 argument we clobber and be more selective in removing notes, but it
4641 does not seem to be worth the effort. */
4644 fixup_tail_calls (void)
4648 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4652 /* There are never REG_EQUIV notes for the incoming arguments
4653 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
4655 && NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
)
4658 note
= find_reg_note (insn
, REG_EQUIV
, 0);
4660 remove_note (insn
, note
);
4661 note
= find_reg_note (insn
, REG_EQUIV
, 0);
4666 /* Traverse a list of TYPES and expand all complex types into their
4669 split_complex_types (tree types
)
4673 /* Before allocating memory, check for the common case of no complex. */
4674 for (p
= types
; p
; p
= TREE_CHAIN (p
))
4676 tree type
= TREE_VALUE (p
);
4677 if (TREE_CODE (type
) == COMPLEX_TYPE
4678 && targetm
.calls
.split_complex_arg (type
))
4684 types
= copy_list (types
);
4686 for (p
= types
; p
; p
= TREE_CHAIN (p
))
4688 tree complex_type
= TREE_VALUE (p
);
4690 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
4691 && targetm
.calls
.split_complex_arg (complex_type
))
4695 /* Rewrite complex type with component type. */
4696 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
4697 next
= TREE_CHAIN (p
);
4699 /* Add another component type for the imaginary part. */
4700 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
4701 TREE_CHAIN (p
) = imag
;
4702 TREE_CHAIN (imag
) = next
;
4704 /* Skip the newly created node. */
4712 /* Output a library call to function ORGFUN (a SYMBOL_REF rtx)
4713 for a value of mode OUTMODE,
4714 with NARGS different arguments, passed as ARGS.
4715 Store the return value if RETVAL is nonzero: store it in VALUE if
4716 VALUE is nonnull, otherwise pick a convenient location. In either
4717 case return the location of the stored value.
4719 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4720 `const' calls, LCT_PURE for `pure' calls, or another LCT_ value for
4721 other types of library calls. */
4724 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
4725 enum libcall_type fn_type
,
4726 machine_mode outmode
, int nargs
, rtx_mode_t
*args
)
4728 /* Total size in bytes of all the stack-parms scanned so far. */
4729 struct args_size args_size
;
4730 /* Size of arguments before any adjustments (such as rounding). */
4731 struct args_size original_args_size
;
4734 /* Todo, choose the correct decl type of orgfun. Sadly this information
4735 isn't present here, so we default to native calling abi here. */
4736 tree fndecl ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
4737 tree fntype ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
4740 CUMULATIVE_ARGS args_so_far_v
;
4741 cumulative_args_t args_so_far
;
4748 struct locate_and_pad_arg_data locate
;
4752 int old_inhibit_defer_pop
= inhibit_defer_pop
;
4753 rtx call_fusage
= 0;
4756 int pcc_struct_value
= 0;
4757 poly_int64 struct_value_size
= 0;
4759 int reg_parm_stack_space
= 0;
4761 rtx_insn
*before_call
;
4762 bool have_push_fusage
;
4763 tree tfom
; /* type_for_mode (outmode, 0) */
4765 #ifdef REG_PARM_STACK_SPACE
4766 /* Define the boundary of the register parm stack space that needs to be
4768 int low_to_save
= 0, high_to_save
= 0;
4769 rtx save_area
= 0; /* Place that it is saved. */
4772 /* Size of the stack reserved for parameter registers. */
4773 unsigned int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
4774 char *initial_stack_usage_map
= stack_usage_map
;
4775 unsigned HOST_WIDE_INT initial_stack_usage_watermark
= stack_usage_watermark
;
4776 char *stack_usage_map_buf
= NULL
;
4778 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
4780 #ifdef REG_PARM_STACK_SPACE
4781 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
4784 /* By default, library functions cannot throw. */
4785 flags
= ECF_NOTHROW
;
4798 flags
|= ECF_NORETURN
;
4801 flags
&= ~ECF_NOTHROW
;
4803 case LCT_RETURNS_TWICE
:
4804 flags
= ECF_RETURNS_TWICE
;
4809 /* Ensure current function's preferred stack boundary is at least
4811 if (crtl
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
4812 crtl
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
4814 /* If this kind of value comes back in memory,
4815 decide where in memory it should come back. */
4816 if (outmode
!= VOIDmode
)
4818 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
4819 if (aggregate_value_p (tfom
, 0))
4821 #ifdef PCC_STATIC_STRUCT_RETURN
4823 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
4824 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
4825 pcc_struct_value
= 1;
4827 value
= gen_reg_rtx (outmode
);
4828 #else /* not PCC_STATIC_STRUCT_RETURN */
4829 struct_value_size
= GET_MODE_SIZE (outmode
);
4830 if (value
!= 0 && MEM_P (value
))
4833 mem_value
= assign_temp (tfom
, 1, 1);
4835 /* This call returns a big structure. */
4836 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
4840 tfom
= void_type_node
;
4842 /* ??? Unfinished: must pass the memory address as an argument. */
4844 /* Copy all the libcall-arguments out of the varargs data
4845 and into a vector ARGVEC.
4847 Compute how to pass each argument. We only support a very small subset
4848 of the full argument passing conventions to limit complexity here since
4849 library functions shouldn't have many args. */
4851 argvec
= XALLOCAVEC (struct arg
, nargs
+ 1);
4852 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
4854 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
4855 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v
, outmode
, fun
);
4857 INIT_CUMULATIVE_ARGS (args_so_far_v
, NULL_TREE
, fun
, 0, nargs
);
4859 args_so_far
= pack_cumulative_args (&args_so_far_v
);
4861 args_size
.constant
= 0;
4868 /* If there's a structure value address to be passed,
4869 either pass it in the special place, or pass it as an extra argument. */
4870 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
4872 rtx addr
= XEXP (mem_value
, 0);
4876 /* Make sure it is a reasonable operand for a move or push insn. */
4877 if (!REG_P (addr
) && !MEM_P (addr
)
4878 && !(CONSTANT_P (addr
)
4879 && targetm
.legitimate_constant_p (Pmode
, addr
)))
4880 addr
= force_operand (addr
, NULL_RTX
);
4882 argvec
[count
].value
= addr
;
4883 argvec
[count
].mode
= Pmode
;
4884 argvec
[count
].partial
= 0;
4886 function_arg_info
ptr_arg (Pmode
, /*named=*/true);
4887 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
, ptr_arg
);
4888 gcc_assert (targetm
.calls
.arg_partial_bytes (args_so_far
, ptr_arg
) == 0);
4890 locate_and_pad_parm (Pmode
, NULL_TREE
,
4891 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4894 argvec
[count
].reg
!= 0,
4896 reg_parm_stack_space
, 0,
4897 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
4899 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
4900 || reg_parm_stack_space
> 0)
4901 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
4903 targetm
.calls
.function_arg_advance (args_so_far
, ptr_arg
);
4908 for (unsigned int i
= 0; count
< nargs
; i
++, count
++)
4910 rtx val
= args
[i
].first
;
4911 function_arg_info
arg (args
[i
].second
, /*named=*/true);
4914 /* We cannot convert the arg value to the mode the library wants here;
4915 must do it earlier where we know the signedness of the arg. */
4916 gcc_assert (arg
.mode
!= BLKmode
4917 && (GET_MODE (val
) == arg
.mode
4918 || GET_MODE (val
) == VOIDmode
));
4920 /* Make sure it is a reasonable operand for a move or push insn. */
4921 if (!REG_P (val
) && !MEM_P (val
)
4922 && !(CONSTANT_P (val
)
4923 && targetm
.legitimate_constant_p (arg
.mode
, val
)))
4924 val
= force_operand (val
, NULL_RTX
);
4926 if (pass_by_reference (&args_so_far_v
, arg
))
4929 int must_copy
= !reference_callee_copied (&args_so_far_v
, arg
);
4931 /* If this was a CONST function, it is now PURE since it now
4933 if (flags
& ECF_CONST
)
4935 flags
&= ~ECF_CONST
;
4939 if (MEM_P (val
) && !must_copy
)
4941 tree val_expr
= MEM_EXPR (val
);
4943 mark_addressable (val_expr
);
4948 slot
= assign_temp (lang_hooks
.types
.type_for_mode (arg
.mode
, 0),
4950 emit_move_insn (slot
, val
);
4953 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
4954 gen_rtx_USE (VOIDmode
, slot
),
4957 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
4958 gen_rtx_CLOBBER (VOIDmode
,
4963 arg
.pass_by_reference
= true;
4964 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
4967 arg
.mode
= promote_function_mode (NULL_TREE
, arg
.mode
, &unsigned_p
,
4969 argvec
[count
].mode
= arg
.mode
;
4970 argvec
[count
].value
= convert_modes (arg
.mode
, GET_MODE (val
), val
,
4972 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
, arg
);
4974 argvec
[count
].partial
4975 = targetm
.calls
.arg_partial_bytes (args_so_far
, arg
);
4977 if (argvec
[count
].reg
== 0
4978 || argvec
[count
].partial
!= 0
4979 || reg_parm_stack_space
> 0)
4981 locate_and_pad_parm (arg
.mode
, NULL_TREE
,
4982 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4985 argvec
[count
].reg
!= 0,
4987 reg_parm_stack_space
, argvec
[count
].partial
,
4988 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
4989 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
4990 gcc_assert (!argvec
[count
].locate
.size
.var
);
4992 #ifdef BLOCK_REG_PADDING
4994 /* The argument is passed entirely in registers. See at which
4995 end it should be padded. */
4996 argvec
[count
].locate
.where_pad
=
4997 BLOCK_REG_PADDING (arg
.mode
, NULL_TREE
,
4998 known_le (GET_MODE_SIZE (arg
.mode
),
5002 targetm
.calls
.function_arg_advance (args_so_far
, arg
);
5005 for (int i
= 0; i
< nargs
; i
++)
5006 if (reg_parm_stack_space
> 0
5007 || argvec
[i
].reg
== 0
5008 || argvec
[i
].partial
!= 0)
5009 update_stack_alignment_for_call (&argvec
[i
].locate
);
5011 /* If this machine requires an external definition for library
5012 functions, write one out. */
5013 assemble_external_libcall (fun
);
5015 original_args_size
= args_size
;
5016 args_size
.constant
= (aligned_upper_bound (args_size
.constant
5017 + stack_pointer_delta
,
5019 - stack_pointer_delta
);
5021 args_size
.constant
= upper_bound (args_size
.constant
,
5022 reg_parm_stack_space
);
5024 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
5025 args_size
.constant
-= reg_parm_stack_space
;
5027 crtl
->outgoing_args_size
= upper_bound (crtl
->outgoing_args_size
,
5028 args_size
.constant
);
5030 if (flag_stack_usage_info
&& !ACCUMULATE_OUTGOING_ARGS
)
5032 poly_int64 pushed
= args_size
.constant
+ pending_stack_adjust
;
5033 current_function_pushed_stack_size
5034 = upper_bound (current_function_pushed_stack_size
, pushed
);
5037 if (ACCUMULATE_OUTGOING_ARGS
)
5039 /* Since the stack pointer will never be pushed, it is possible for
5040 the evaluation of a parm to clobber something we have already
5041 written to the stack. Since most function calls on RISC machines
5042 do not use the stack, this is uncommon, but must work correctly.
5044 Therefore, we save any area of the stack that was already written
5045 and that we are using. Here we set up to do this by making a new
5046 stack usage map from the old one.
5048 Another approach might be to try to reorder the argument
5049 evaluations to avoid this conflicting stack usage. */
5051 needed
= args_size
.constant
;
5053 /* Since we will be writing into the entire argument area, the
5054 map must be allocated for its entire size, not just the part that
5055 is the responsibility of the caller. */
5056 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
5057 needed
+= reg_parm_stack_space
;
5059 poly_int64 limit
= needed
;
5060 if (ARGS_GROW_DOWNWARD
)
5063 /* For polynomial sizes, this is the maximum possible size needed
5064 for arguments with a constant size and offset. */
5065 HOST_WIDE_INT const_limit
= constant_lower_bound (limit
);
5066 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
5069 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
5070 stack_usage_map
= stack_usage_map_buf
;
5072 if (initial_highest_arg_in_use
)
5073 memcpy (stack_usage_map
, initial_stack_usage_map
,
5074 initial_highest_arg_in_use
);
5076 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
5077 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
5078 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
5081 /* We must be careful to use virtual regs before they're instantiated,
5082 and real regs afterwards. Loop optimization, for example, can create
5083 new libcalls after we've instantiated the virtual regs, and if we
5084 use virtuals anyway, they won't match the rtl patterns. */
5086 if (virtuals_instantiated
)
5087 argblock
= plus_constant (Pmode
, stack_pointer_rtx
,
5088 STACK_POINTER_OFFSET
);
5090 argblock
= virtual_outgoing_args_rtx
;
5095 argblock
= push_block (gen_int_mode (args_size
.constant
, Pmode
), 0, 0);
5098 /* We push args individually in reverse order, perform stack alignment
5099 before the first push (the last arg). */
5101 anti_adjust_stack (gen_int_mode (args_size
.constant
5102 - original_args_size
.constant
,
5107 #ifdef REG_PARM_STACK_SPACE
5108 if (ACCUMULATE_OUTGOING_ARGS
)
5110 /* The argument list is the property of the called routine and it
5111 may clobber it. If the fixed area has been used for previous
5112 parameters, we must save and restore it. */
5113 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
5114 &low_to_save
, &high_to_save
);
5118 /* When expanding a normal call, args are stored in push order,
5119 which is the reverse of what we have here. */
5120 bool any_regs
= false;
5121 for (int i
= nargs
; i
-- > 0; )
5122 if (argvec
[i
].reg
!= NULL_RTX
)
5124 targetm
.calls
.call_args (argvec
[i
].reg
, NULL_TREE
);
5128 targetm
.calls
.call_args (pc_rtx
, NULL_TREE
);
5130 /* Push the args that need to be pushed. */
5132 have_push_fusage
= false;
5134 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5135 are to be pushed. */
5136 for (count
= 0; count
< nargs
; count
++, argnum
--)
5138 machine_mode mode
= argvec
[argnum
].mode
;
5139 rtx val
= argvec
[argnum
].value
;
5140 rtx reg
= argvec
[argnum
].reg
;
5141 int partial
= argvec
[argnum
].partial
;
5142 unsigned int parm_align
= argvec
[argnum
].locate
.boundary
;
5143 poly_int64 lower_bound
= 0, upper_bound
= 0;
5145 if (! (reg
!= 0 && partial
== 0))
5149 if (ACCUMULATE_OUTGOING_ARGS
)
5151 /* If this is being stored into a pre-allocated, fixed-size,
5152 stack area, save any previous data at that location. */
5154 if (ARGS_GROW_DOWNWARD
)
5156 /* stack_slot is negative, but we want to index stack_usage_map
5157 with positive values. */
5158 upper_bound
= -argvec
[argnum
].locate
.slot_offset
.constant
+ 1;
5159 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
5163 lower_bound
= argvec
[argnum
].locate
.slot_offset
.constant
;
5164 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
5167 if (stack_region_maybe_used_p (lower_bound
, upper_bound
,
5168 reg_parm_stack_space
))
5170 /* We need to make a save area. */
5172 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
5173 machine_mode save_mode
5174 = int_mode_for_size (size
, 1).else_blk ();
5176 = plus_constant (Pmode
, argblock
,
5177 argvec
[argnum
].locate
.offset
.constant
);
5179 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
5181 if (save_mode
== BLKmode
)
5183 argvec
[argnum
].save_area
5184 = assign_stack_temp (BLKmode
,
5185 argvec
[argnum
].locate
.size
.constant
5188 emit_block_move (validize_mem
5189 (copy_rtx (argvec
[argnum
].save_area
)),
5192 (argvec
[argnum
].locate
.size
.constant
,
5194 BLOCK_OP_CALL_PARM
);
5198 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
5200 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
5205 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, parm_align
,
5206 partial
, reg
, 0, argblock
,
5208 (argvec
[argnum
].locate
.offset
.constant
, Pmode
)),
5209 reg_parm_stack_space
,
5210 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
), false);
5212 /* Now mark the segment we just used. */
5213 if (ACCUMULATE_OUTGOING_ARGS
)
5214 mark_stack_region_used (lower_bound
, upper_bound
);
5218 /* Indicate argument access so that alias.c knows that these
5221 use
= plus_constant (Pmode
, argblock
,
5222 argvec
[argnum
].locate
.offset
.constant
);
5223 else if (have_push_fusage
)
5227 /* When arguments are pushed, trying to tell alias.c where
5228 exactly this argument is won't work, because the
5229 auto-increment causes confusion. So we merely indicate
5230 that we access something with a known mode somewhere on
5232 use
= gen_rtx_PLUS (Pmode
, stack_pointer_rtx
,
5233 gen_rtx_SCRATCH (Pmode
));
5234 have_push_fusage
= true;
5236 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
5237 use
= gen_rtx_USE (VOIDmode
, use
);
5238 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
5244 fun
= prepare_call_address (NULL
, fun
, NULL
, &call_fusage
, 0, 0);
5246 /* Now load any reg parms into their regs. */
5248 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5249 are to be pushed. */
5250 for (count
= 0; count
< nargs
; count
++, argnum
--)
5252 machine_mode mode
= argvec
[argnum
].mode
;
5253 rtx val
= argvec
[argnum
].value
;
5254 rtx reg
= argvec
[argnum
].reg
;
5255 int partial
= argvec
[argnum
].partial
;
5257 /* Handle calls that pass values in multiple non-contiguous
5258 locations. The PA64 has examples of this for library calls. */
5259 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
5260 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
5261 else if (reg
!= 0 && partial
== 0)
5263 emit_move_insn (reg
, val
);
5264 #ifdef BLOCK_REG_PADDING
5265 poly_int64 size
= GET_MODE_SIZE (argvec
[argnum
].mode
);
5267 /* Copied from load_register_parameters. */
5269 /* Handle case where we have a value that needs shifting
5270 up to the msb. eg. a QImode value and we're padding
5271 upward on a BYTES_BIG_ENDIAN machine. */
5272 if (known_lt (size
, UNITS_PER_WORD
)
5273 && (argvec
[argnum
].locate
.where_pad
5274 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
5277 poly_int64 shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
5279 /* Assigning REG here rather than a temp makes CALL_FUSAGE
5280 report the whole reg as used. Strictly speaking, the
5281 call only uses SIZE bytes at the msb end, but it doesn't
5282 seem worth generating rtl to say that. */
5283 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
5284 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
, shift
, reg
, 1);
5286 emit_move_insn (reg
, x
);
5294 /* Any regs containing parms remain in use through the call. */
5295 for (count
= 0; count
< nargs
; count
++)
5297 rtx reg
= argvec
[count
].reg
;
5298 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
5299 use_group_regs (&call_fusage
, reg
);
5302 int partial
= argvec
[count
].partial
;
5306 gcc_assert (partial
% UNITS_PER_WORD
== 0);
5307 nregs
= partial
/ UNITS_PER_WORD
;
5308 use_regs (&call_fusage
, REGNO (reg
), nregs
);
5311 use_reg (&call_fusage
, reg
);
5315 /* Pass the function the address in which to return a structure value. */
5316 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
5318 emit_move_insn (struct_value
,
5320 force_operand (XEXP (mem_value
, 0),
5322 if (REG_P (struct_value
))
5323 use_reg (&call_fusage
, struct_value
);
5326 /* Don't allow popping to be deferred, since then
5327 cse'ing of library calls could delete a call and leave the pop. */
5329 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
5330 ? hard_libcall_value (outmode
, orgfun
) : NULL_RTX
);
5332 /* Stack must be properly aligned now. */
5333 gcc_assert (multiple_p (stack_pointer_delta
,
5334 PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
));
5336 before_call
= get_last_insn ();
5338 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
5339 will set inhibit_defer_pop to that value. */
5340 /* The return type is needed to decide how many bytes the function pops.
5341 Signedness plays no role in that, so for simplicity, we pretend it's
5342 always signed. We also assume that the list of arguments passed has
5343 no impact, so we pretend it is unknown. */
5345 emit_call_1 (fun
, NULL
,
5346 get_identifier (XSTR (orgfun
, 0)),
5347 build_function_type (tfom
, NULL_TREE
),
5348 original_args_size
.constant
, args_size
.constant
,
5350 targetm
.calls
.function_arg (args_so_far
,
5351 function_arg_info::end_marker ()),
5353 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, args_so_far
);
5358 gcc_assert (GET_CODE (datum
) == SYMBOL_REF
);
5359 rtx_call_insn
*last
= last_call_insn ();
5360 add_reg_note (last
, REG_CALL_DECL
, datum
);
5363 /* Right-shift returned value if necessary. */
5364 if (!pcc_struct_value
5365 && TYPE_MODE (tfom
) != BLKmode
5366 && targetm
.calls
.return_in_msb (tfom
))
5368 shift_return_value (TYPE_MODE (tfom
), false, valreg
);
5369 valreg
= gen_rtx_REG (TYPE_MODE (tfom
), REGNO (valreg
));
5372 targetm
.calls
.end_call_args ();
5374 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
5375 that it should complain if nonvolatile values are live. For
5376 functions that cannot return, inform flow that control does not
5378 if (flags
& ECF_NORETURN
)
5380 /* The barrier note must be emitted
5381 immediately after the CALL_INSN. Some ports emit more than
5382 just a CALL_INSN above, so we must search for it here. */
5383 rtx_insn
*last
= get_last_insn ();
5384 while (!CALL_P (last
))
5386 last
= PREV_INSN (last
);
5387 /* There was no CALL_INSN? */
5388 gcc_assert (last
!= before_call
);
5391 emit_barrier_after (last
);
5394 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
5395 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
5396 if (flags
& ECF_NOTHROW
)
5398 rtx_insn
*last
= get_last_insn ();
5399 while (!CALL_P (last
))
5401 last
= PREV_INSN (last
);
5402 /* There was no CALL_INSN? */
5403 gcc_assert (last
!= before_call
);
5406 make_reg_eh_region_note_nothrow_nononlocal (last
);
5409 /* Now restore inhibit_defer_pop to its actual original value. */
5414 /* Copy the value to the right place. */
5415 if (outmode
!= VOIDmode
&& retval
)
5421 if (value
!= mem_value
)
5422 emit_move_insn (value
, mem_value
);
5424 else if (GET_CODE (valreg
) == PARALLEL
)
5427 value
= gen_reg_rtx (outmode
);
5428 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
5432 /* Convert to the proper mode if a promotion has been active. */
5433 if (GET_MODE (valreg
) != outmode
)
5435 int unsignedp
= TYPE_UNSIGNED (tfom
);
5437 gcc_assert (promote_function_mode (tfom
, outmode
, &unsignedp
,
5438 fndecl
? TREE_TYPE (fndecl
) : fntype
, 1)
5439 == GET_MODE (valreg
));
5440 valreg
= convert_modes (outmode
, GET_MODE (valreg
), valreg
, 0);
5444 emit_move_insn (value
, valreg
);
5450 if (ACCUMULATE_OUTGOING_ARGS
)
5452 #ifdef REG_PARM_STACK_SPACE
5454 restore_fixed_argument_area (save_area
, argblock
,
5455 high_to_save
, low_to_save
);
5458 /* If we saved any argument areas, restore them. */
5459 for (count
= 0; count
< nargs
; count
++)
5460 if (argvec
[count
].save_area
)
5462 machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
5463 rtx adr
= plus_constant (Pmode
, argblock
,
5464 argvec
[count
].locate
.offset
.constant
);
5465 rtx stack_area
= gen_rtx_MEM (save_mode
,
5466 memory_address (save_mode
, adr
));
5468 if (save_mode
== BLKmode
)
5469 emit_block_move (stack_area
,
5471 (copy_rtx (argvec
[count
].save_area
)),
5473 (argvec
[count
].locate
.size
.constant
, Pmode
)),
5474 BLOCK_OP_CALL_PARM
);
5476 emit_move_insn (stack_area
, argvec
[count
].save_area
);
5479 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
5480 stack_usage_map
= initial_stack_usage_map
;
5481 stack_usage_watermark
= initial_stack_usage_watermark
;
5484 free (stack_usage_map_buf
);
5491 /* Store a single argument for a function call
5492 into the register or memory area where it must be passed.
5493 *ARG describes the argument value and where to pass it.
5495 ARGBLOCK is the address of the stack-block for all the arguments,
5496 or 0 on a machine where arguments are pushed individually.
5498 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
5499 so must be careful about how the stack is used.
5501 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
5502 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
5503 that we need not worry about saving and restoring the stack.
5505 FNDECL is the declaration of the function we are calling.
5507 Return nonzero if this arg should cause sibcall failure,
5511 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
5512 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
5514 tree pval
= arg
->tree_value
;
5517 poly_int64 used
= 0;
5518 poly_int64 lower_bound
= 0, upper_bound
= 0;
5519 int sibcall_failure
= 0;
5521 if (TREE_CODE (pval
) == ERROR_MARK
)
5524 /* Push a new temporary level for any temporaries we make for
5528 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
5530 /* If this is being stored into a pre-allocated, fixed-size, stack area,
5531 save any previous data at that location. */
5532 if (argblock
&& ! variable_size
&& arg
->stack
)
5534 if (ARGS_GROW_DOWNWARD
)
5536 /* stack_slot is negative, but we want to index stack_usage_map
5537 with positive values. */
5538 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
5540 rtx offset
= XEXP (XEXP (arg
->stack_slot
, 0), 1);
5541 upper_bound
= -rtx_to_poly_int64 (offset
) + 1;
5546 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
5550 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
5552 rtx offset
= XEXP (XEXP (arg
->stack_slot
, 0), 1);
5553 lower_bound
= rtx_to_poly_int64 (offset
);
5558 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
5561 if (stack_region_maybe_used_p (lower_bound
, upper_bound
,
5562 reg_parm_stack_space
))
5564 /* We need to make a save area. */
5565 poly_uint64 size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
5566 machine_mode save_mode
5567 = int_mode_for_size (size
, 1).else_blk ();
5568 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
5569 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
5571 if (save_mode
== BLKmode
)
5574 = assign_temp (TREE_TYPE (arg
->tree_value
), 1, 1);
5575 preserve_temp_slots (arg
->save_area
);
5576 emit_block_move (validize_mem (copy_rtx (arg
->save_area
)),
5579 (arg
->locate
.size
.constant
, Pmode
)),
5580 BLOCK_OP_CALL_PARM
);
5584 arg
->save_area
= gen_reg_rtx (save_mode
);
5585 emit_move_insn (arg
->save_area
, stack_area
);
5591 /* If this isn't going to be placed on both the stack and in registers,
5592 set up the register and number of words. */
5593 if (! arg
->pass_on_stack
)
5595 if (flags
& ECF_SIBCALL
)
5596 reg
= arg
->tail_call_reg
;
5599 partial
= arg
->partial
;
5602 /* Being passed entirely in a register. We shouldn't be called in
5604 gcc_assert (reg
== 0 || partial
!= 0);
5606 /* If this arg needs special alignment, don't load the registers
5608 if (arg
->n_aligned_regs
!= 0)
5611 /* If this is being passed partially in a register, we can't evaluate
5612 it directly into its stack slot. Otherwise, we can. */
5613 if (arg
->value
== 0)
5615 /* stack_arg_under_construction is nonzero if a function argument is
5616 being evaluated directly into the outgoing argument list and
5617 expand_call must take special action to preserve the argument list
5618 if it is called recursively.
5620 For scalar function arguments stack_usage_map is sufficient to
5621 determine which stack slots must be saved and restored. Scalar
5622 arguments in general have pass_on_stack == 0.
5624 If this argument is initialized by a function which takes the
5625 address of the argument (a C++ constructor or a C function
5626 returning a BLKmode structure), then stack_usage_map is
5627 insufficient and expand_call must push the stack around the
5628 function call. Such arguments have pass_on_stack == 1.
5630 Note that it is always safe to set stack_arg_under_construction,
5631 but this generates suboptimal code if set when not needed. */
5633 if (arg
->pass_on_stack
)
5634 stack_arg_under_construction
++;
5636 arg
->value
= expand_expr (pval
,
5638 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
5639 ? NULL_RTX
: arg
->stack
,
5640 VOIDmode
, EXPAND_STACK_PARM
);
5642 /* If we are promoting object (or for any other reason) the mode
5643 doesn't agree, convert the mode. */
5645 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
5646 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
5647 arg
->value
, arg
->unsignedp
);
5649 if (arg
->pass_on_stack
)
5650 stack_arg_under_construction
--;
5653 /* Check for overlap with already clobbered argument area. */
5654 if ((flags
& ECF_SIBCALL
)
5655 && MEM_P (arg
->value
)
5656 && mem_might_overlap_already_clobbered_arg_p (XEXP (arg
->value
, 0),
5657 arg
->locate
.size
.constant
))
5658 sibcall_failure
= 1;
5660 /* Don't allow anything left on stack from computation
5661 of argument to alloca. */
5662 if (flags
& ECF_MAY_BE_ALLOCA
)
5663 do_pending_stack_adjust ();
5665 if (arg
->value
== arg
->stack
)
5666 /* If the value is already in the stack slot, we are done. */
5668 else if (arg
->mode
!= BLKmode
)
5670 unsigned int parm_align
;
5672 /* Argument is a scalar, not entirely passed in registers.
5673 (If part is passed in registers, arg->partial says how much
5674 and emit_push_insn will take care of putting it there.)
5676 Push it, and if its size is less than the
5677 amount of space allocated to it,
5678 also bump stack pointer by the additional space.
5679 Note that in C the default argument promotions
5680 will prevent such mismatches. */
5682 poly_int64 size
= (TYPE_EMPTY_P (TREE_TYPE (pval
))
5683 ? 0 : GET_MODE_SIZE (arg
->mode
));
5685 /* Compute how much space the push instruction will push.
5686 On many machines, pushing a byte will advance the stack
5687 pointer by a halfword. */
5688 #ifdef PUSH_ROUNDING
5689 size
= PUSH_ROUNDING (size
);
5693 /* Compute how much space the argument should get:
5694 round up to a multiple of the alignment for arguments. */
5695 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5697 /* At the moment we don't (need to) support ABIs for which the
5698 padding isn't known at compile time. In principle it should
5699 be easy to add though. */
5700 used
= force_align_up (size
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
5702 /* Compute the alignment of the pushed argument. */
5703 parm_align
= arg
->locate
.boundary
;
5704 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5707 poly_int64 pad
= used
- size
;
5708 unsigned int pad_align
= known_alignment (pad
) * BITS_PER_UNIT
;
5710 parm_align
= MIN (parm_align
, pad_align
);
5713 /* This isn't already where we want it on the stack, so put it there.
5714 This can either be done with push or copy insns. */
5715 if (maybe_ne (used
, 0)
5716 && !emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
),
5717 NULL_RTX
, parm_align
, partial
, reg
, used
- size
,
5718 argblock
, ARGS_SIZE_RTX (arg
->locate
.offset
),
5719 reg_parm_stack_space
,
5720 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
), true))
5721 sibcall_failure
= 1;
5723 /* Unless this is a partially-in-register argument, the argument is now
5726 arg
->value
= arg
->stack
;
5730 /* BLKmode, at least partly to be pushed. */
5732 unsigned int parm_align
;
5736 /* Pushing a nonscalar.
5737 If part is passed in registers, PARTIAL says how much
5738 and emit_push_insn will take care of putting it there. */
5740 /* Round its size up to a multiple
5741 of the allocation unit for arguments. */
5743 if (arg
->locate
.size
.var
!= 0)
5746 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
5750 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
5751 for BLKmode is careful to avoid it. */
5752 excess
= (arg
->locate
.size
.constant
5753 - arg_int_size_in_bytes (TREE_TYPE (pval
))
5755 size_rtx
= expand_expr (arg_size_in_bytes (TREE_TYPE (pval
)),
5756 NULL_RTX
, TYPE_MODE (sizetype
),
5760 parm_align
= arg
->locate
.boundary
;
5762 /* When an argument is padded down, the block is aligned to
5763 PARM_BOUNDARY, but the actual argument isn't. */
5764 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5767 if (arg
->locate
.size
.var
)
5768 parm_align
= BITS_PER_UNIT
;
5771 unsigned int excess_align
5772 = known_alignment (excess
) * BITS_PER_UNIT
;
5773 if (excess_align
!= 0)
5774 parm_align
= MIN (parm_align
, excess_align
);
5778 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
5780 /* emit_push_insn might not work properly if arg->value and
5781 argblock + arg->locate.offset areas overlap. */
5785 if (strip_offset (XEXP (x
, 0), &i
)
5786 == crtl
->args
.internal_arg_pointer
)
5788 /* arg.locate doesn't contain the pretend_args_size offset,
5789 it's part of argblock. Ensure we don't count it in I. */
5790 if (STACK_GROWS_DOWNWARD
)
5791 i
-= crtl
->args
.pretend_args_size
;
5793 i
+= crtl
->args
.pretend_args_size
;
5795 /* expand_call should ensure this. */
5796 gcc_assert (!arg
->locate
.offset
.var
5797 && arg
->locate
.size
.var
== 0);
5798 poly_int64 size_val
= rtx_to_poly_int64 (size_rtx
);
5800 if (known_eq (arg
->locate
.offset
.constant
, i
))
5802 /* Even though they appear to be at the same location,
5803 if part of the outgoing argument is in registers,
5804 they aren't really at the same location. Check for
5805 this by making sure that the incoming size is the
5806 same as the outgoing size. */
5807 if (maybe_ne (arg
->locate
.size
.constant
, size_val
))
5808 sibcall_failure
= 1;
5810 else if (maybe_in_range_p (arg
->locate
.offset
.constant
,
5812 sibcall_failure
= 1;
5813 /* Use arg->locate.size.constant instead of size_rtx
5814 because we only care about the part of the argument
5816 else if (maybe_in_range_p (i
, arg
->locate
.offset
.constant
,
5817 arg
->locate
.size
.constant
))
5818 sibcall_failure
= 1;
5822 if (!CONST_INT_P (size_rtx
) || INTVAL (size_rtx
) != 0)
5823 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
5824 parm_align
, partial
, reg
, excess
, argblock
,
5825 ARGS_SIZE_RTX (arg
->locate
.offset
),
5826 reg_parm_stack_space
,
5827 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
), false);
5829 /* Unless this is a partially-in-register argument, the argument is now
5832 ??? Unlike the case above, in which we want the actual
5833 address of the data, so that we can load it directly into a
5834 register, here we want the address of the stack slot, so that
5835 it's properly aligned for word-by-word copying or something
5836 like that. It's not clear that this is always correct. */
5838 arg
->value
= arg
->stack_slot
;
5841 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
5843 tree type
= TREE_TYPE (arg
->tree_value
);
5845 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
5846 int_size_in_bytes (type
));
5849 /* Mark all slots this store used. */
5850 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
5851 && argblock
&& ! variable_size
&& arg
->stack
)
5852 mark_stack_region_used (lower_bound
, upper_bound
);
5854 /* Once we have pushed something, pops can't safely
5855 be deferred during the rest of the arguments. */
5858 /* Free any temporary slots made in processing this argument. */
5861 return sibcall_failure
;
5864 /* Nonzero if we do not know how to pass ARG solely in registers. */
5867 must_pass_in_stack_var_size (const function_arg_info
&arg
)
5872 /* If the type has variable size... */
5873 if (TREE_CODE (TYPE_SIZE (arg
.type
)) != INTEGER_CST
)
5876 /* If the type is marked as addressable (it is required
5877 to be constructed into the stack)... */
5878 if (TREE_ADDRESSABLE (arg
.type
))
5884 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5885 takes trailing padding of a structure into account. */
5886 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5889 must_pass_in_stack_var_size_or_pad (const function_arg_info
&arg
)
5894 /* If the type has variable size... */
5895 if (TREE_CODE (TYPE_SIZE (arg
.type
)) != INTEGER_CST
)
5898 /* If the type is marked as addressable (it is required
5899 to be constructed into the stack)... */
5900 if (TREE_ADDRESSABLE (arg
.type
))
5903 if (TYPE_EMPTY_P (arg
.type
))
5906 /* If the padding and mode of the type is such that a copy into
5907 a register would put it into the wrong part of the register. */
5908 if (arg
.mode
== BLKmode
5909 && int_size_in_bytes (arg
.type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
5910 && (targetm
.calls
.function_arg_padding (arg
.mode
, arg
.type
)
5911 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
5917 /* Return true if TYPE must be passed on the stack when passed to
5918 the "..." arguments of a function. */
5921 must_pass_va_arg_in_stack (tree type
)
5923 function_arg_info
arg (type
, /*named=*/false);
5924 return targetm
.calls
.must_pass_in_stack (arg
);
5927 /* Tell the garbage collector about GTY markers in this source file. */
5928 #include "gt-calls.h"