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 ((TREE_CODE (type
) == UNION_TYPE
|| TREE_CODE (type
) == RECORD_TYPE
)
1995 && TYPE_TRANSPARENT_AGGR (type
))
1996 type
= TREE_TYPE (first_field (type
));
1998 /* Decide where to pass this arg.
2000 args[i].reg is nonzero if all or part is passed in registers.
2002 args[i].partial is nonzero if part but not all is passed in registers,
2003 and the exact value says how many bytes are passed in registers.
2005 args[i].pass_on_stack is nonzero if the argument must at least be
2006 computed on the stack. It may then be loaded back into registers
2007 if args[i].reg is nonzero.
2009 These decisions are driven by the FUNCTION_... macros and must agree
2010 with those made by function.c. */
2012 /* See if this argument should be passed by invisible reference. */
2013 function_arg_info
arg (type
, argpos
< n_named_args
);
2014 if (pass_by_reference (args_so_far_pnt
, arg
))
2017 tree base
= NULL_TREE
;
2019 callee_copies
= reference_callee_copied (args_so_far_pnt
, arg
);
2021 /* If we're compiling a thunk, pass through invisible references
2022 instead of making a copy. */
2023 if (call_from_thunk_p
2025 && !TREE_ADDRESSABLE (type
)
2026 && (base
= get_base_address (args
[i
].tree_value
))
2027 && TREE_CODE (base
) != SSA_NAME
2028 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
)))))
2030 /* We may have turned the parameter value into an SSA name.
2031 Go back to the original parameter so we can take the
2033 if (TREE_CODE (args
[i
].tree_value
) == SSA_NAME
)
2035 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args
[i
].tree_value
));
2036 args
[i
].tree_value
= SSA_NAME_VAR (args
[i
].tree_value
);
2037 gcc_assert (TREE_CODE (args
[i
].tree_value
) == PARM_DECL
);
2039 /* Argument setup code may have copied the value to register. We
2040 revert that optimization now because the tail call code must
2041 use the original location. */
2042 if (TREE_CODE (args
[i
].tree_value
) == PARM_DECL
2043 && !MEM_P (DECL_RTL (args
[i
].tree_value
))
2044 && DECL_INCOMING_RTL (args
[i
].tree_value
)
2045 && MEM_P (DECL_INCOMING_RTL (args
[i
].tree_value
)))
2046 set_decl_rtl (args
[i
].tree_value
,
2047 DECL_INCOMING_RTL (args
[i
].tree_value
));
2049 mark_addressable (args
[i
].tree_value
);
2051 /* We can't use sibcalls if a callee-copied argument is
2052 stored in the current function's frame. */
2053 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
2055 *may_tailcall
= false;
2056 maybe_complain_about_tail_call (exp
,
2057 "a callee-copied argument is"
2058 " stored in the current"
2059 " function's frame");
2062 args
[i
].tree_value
= build_fold_addr_expr_loc (loc
,
2063 args
[i
].tree_value
);
2064 type
= TREE_TYPE (args
[i
].tree_value
);
2066 if (*ecf_flags
& ECF_CONST
)
2067 *ecf_flags
&= ~(ECF_CONST
| ECF_LOOPING_CONST_OR_PURE
);
2071 /* We make a copy of the object and pass the address to the
2072 function being called. */
2075 if (!COMPLETE_TYPE_P (type
)
2076 || TREE_CODE (TYPE_SIZE_UNIT (type
)) != INTEGER_CST
2077 || (flag_stack_check
== GENERIC_STACK_CHECK
2078 && compare_tree_int (TYPE_SIZE_UNIT (type
),
2079 STACK_CHECK_MAX_VAR_SIZE
) > 0))
2081 /* This is a variable-sized object. Make space on the stack
2083 rtx size_rtx
= expr_size (args
[i
].tree_value
);
2085 if (*old_stack_level
== 0)
2087 emit_stack_save (SAVE_BLOCK
, old_stack_level
);
2088 *old_pending_adj
= pending_stack_adjust
;
2089 pending_stack_adjust
= 0;
2092 /* We can pass TRUE as the 4th argument because we just
2093 saved the stack pointer and will restore it right after
2095 copy
= allocate_dynamic_stack_space (size_rtx
,
2098 max_int_size_in_bytes
2101 copy
= gen_rtx_MEM (BLKmode
, copy
);
2102 set_mem_attributes (copy
, type
, 1);
2105 copy
= assign_temp (type
, 1, 0);
2107 store_expr (args
[i
].tree_value
, copy
, 0, false, false);
2109 /* Just change the const function to pure and then let
2110 the next test clear the pure based on
2112 if (*ecf_flags
& ECF_CONST
)
2114 *ecf_flags
&= ~ECF_CONST
;
2115 *ecf_flags
|= ECF_PURE
;
2118 if (!callee_copies
&& *ecf_flags
& ECF_PURE
)
2119 *ecf_flags
&= ~(ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
2122 = build_fold_addr_expr_loc (loc
, make_tree (type
, copy
));
2123 type
= TREE_TYPE (args
[i
].tree_value
);
2124 *may_tailcall
= false;
2125 maybe_complain_about_tail_call (exp
,
2126 "argument must be passed"
2129 arg
.pass_by_reference
= true;
2132 unsignedp
= TYPE_UNSIGNED (type
);
2135 = promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
2136 fndecl
? TREE_TYPE (fndecl
) : fntype
, 0);
2138 args
[i
].unsignedp
= unsignedp
;
2139 args
[i
].mode
= arg
.mode
;
2141 targetm
.calls
.warn_parameter_passing_abi (args_so_far
, type
);
2143 args
[i
].reg
= targetm
.calls
.function_arg (args_so_far
, arg
);
2145 if (args
[i
].reg
&& CONST_INT_P (args
[i
].reg
))
2148 /* If this is a sibling call and the machine has register windows, the
2149 register window has to be unwinded before calling the routine, so
2150 arguments have to go into the incoming registers. */
2151 if (targetm
.calls
.function_incoming_arg
!= targetm
.calls
.function_arg
)
2152 args
[i
].tail_call_reg
2153 = targetm
.calls
.function_incoming_arg (args_so_far
, arg
);
2155 args
[i
].tail_call_reg
= args
[i
].reg
;
2158 args
[i
].partial
= targetm
.calls
.arg_partial_bytes (args_so_far
, arg
);
2160 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (arg
);
2162 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
2163 it means that we are to pass this arg in the register(s) designated
2164 by the PARALLEL, but also to pass it in the stack. */
2165 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
2166 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
2167 args
[i
].pass_on_stack
= 1;
2169 /* If this is an addressable type, we must preallocate the stack
2170 since we must evaluate the object into its final location.
2172 If this is to be passed in both registers and the stack, it is simpler
2174 if (TREE_ADDRESSABLE (type
)
2175 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
2176 *must_preallocate
= 1;
2178 /* Compute the stack-size of this argument. */
2179 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
2180 || reg_parm_stack_space
> 0
2181 || args
[i
].pass_on_stack
)
2182 locate_and_pad_parm (arg
.mode
, type
,
2183 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2188 reg_parm_stack_space
,
2189 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
2190 fndecl
, args_size
, &args
[i
].locate
);
2191 #ifdef BLOCK_REG_PADDING
2193 /* The argument is passed entirely in registers. See at which
2194 end it should be padded. */
2195 args
[i
].locate
.where_pad
=
2196 BLOCK_REG_PADDING (arg
.mode
, type
,
2197 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
2200 /* Update ARGS_SIZE, the total stack space for args so far. */
2202 args_size
->constant
+= args
[i
].locate
.size
.constant
;
2203 if (args
[i
].locate
.size
.var
)
2204 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
2206 /* Increment ARGS_SO_FAR, which has info about which arg-registers
2207 have been used, etc. */
2209 /* ??? Traditionally we've passed TYPE_MODE here, instead of the
2210 promoted_mode used for function_arg above. However, the
2211 corresponding handling of incoming arguments in function.c
2212 does pass the promoted mode. */
2213 arg
.mode
= TYPE_MODE (type
);
2214 targetm
.calls
.function_arg_advance (args_so_far
, arg
);
2216 /* Store argument values for functions decorated with attribute
2218 if (argpos
== alloc_idx
[0])
2219 alloc_args
[0] = args
[i
].tree_value
;
2220 else if (argpos
== alloc_idx
[1])
2221 alloc_args
[1] = args
[i
].tree_value
;
2226 /* Check the arguments of functions decorated with attribute
2228 maybe_warn_alloc_args_overflow (fndecl
, exp
, alloc_args
, alloc_idx
);
2231 /* Detect passing non-string arguments to functions expecting
2232 nul-terminated strings. */
2233 maybe_warn_nonstring_arg (fndecl
, exp
);
2236 /* Update ARGS_SIZE to contain the total size for the argument block.
2237 Return the original constant component of the argument block's size.
2239 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
2240 for arguments passed in registers. */
2243 compute_argument_block_size (int reg_parm_stack_space
,
2244 struct args_size
*args_size
,
2245 tree fndecl ATTRIBUTE_UNUSED
,
2246 tree fntype ATTRIBUTE_UNUSED
,
2247 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
2249 poly_int64 unadjusted_args_size
= args_size
->constant
;
2251 /* For accumulate outgoing args mode we don't need to align, since the frame
2252 will be already aligned. Align to STACK_BOUNDARY in order to prevent
2253 backends from generating misaligned frame sizes. */
2254 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
2255 preferred_stack_boundary
= STACK_BOUNDARY
;
2257 /* Compute the actual size of the argument block required. The variable
2258 and constant sizes must be combined, the size may have to be rounded,
2259 and there may be a minimum required size. */
2263 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
2264 args_size
->constant
= 0;
2266 preferred_stack_boundary
/= BITS_PER_UNIT
;
2267 if (preferred_stack_boundary
> 1)
2269 /* We don't handle this case yet. To handle it correctly we have
2270 to add the delta, round and subtract the delta.
2271 Currently no machine description requires this support. */
2272 gcc_assert (multiple_p (stack_pointer_delta
,
2273 preferred_stack_boundary
));
2274 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
2277 if (reg_parm_stack_space
> 0)
2280 = size_binop (MAX_EXPR
, args_size
->var
,
2281 ssize_int (reg_parm_stack_space
));
2283 /* The area corresponding to register parameters is not to count in
2284 the size of the block we need. So make the adjustment. */
2285 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2287 = size_binop (MINUS_EXPR
, args_size
->var
,
2288 ssize_int (reg_parm_stack_space
));
2293 preferred_stack_boundary
/= BITS_PER_UNIT
;
2294 if (preferred_stack_boundary
< 1)
2295 preferred_stack_boundary
= 1;
2296 args_size
->constant
= (aligned_upper_bound (args_size
->constant
2297 + stack_pointer_delta
,
2298 preferred_stack_boundary
)
2299 - stack_pointer_delta
);
2301 args_size
->constant
= upper_bound (args_size
->constant
,
2302 reg_parm_stack_space
);
2304 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2305 args_size
->constant
-= reg_parm_stack_space
;
2307 return unadjusted_args_size
;
2310 /* Precompute parameters as needed for a function call.
2312 FLAGS is mask of ECF_* constants.
2314 NUM_ACTUALS is the number of arguments.
2316 ARGS is an array containing information for each argument; this
2317 routine fills in the INITIAL_VALUE and VALUE fields for each
2318 precomputed argument. */
2321 precompute_arguments (int num_actuals
, struct arg_data
*args
)
2325 /* If this is a libcall, then precompute all arguments so that we do not
2326 get extraneous instructions emitted as part of the libcall sequence. */
2328 /* If we preallocated the stack space, and some arguments must be passed
2329 on the stack, then we must precompute any parameter which contains a
2330 function call which will store arguments on the stack.
2331 Otherwise, evaluating the parameter may clobber previous parameters
2332 which have already been stored into the stack. (we have code to avoid
2333 such case by saving the outgoing stack arguments, but it results in
2335 if (!ACCUMULATE_OUTGOING_ARGS
)
2338 for (i
= 0; i
< num_actuals
; i
++)
2343 if (TREE_CODE (args
[i
].tree_value
) != CALL_EXPR
)
2346 /* If this is an addressable type, we cannot pre-evaluate it. */
2347 type
= TREE_TYPE (args
[i
].tree_value
);
2348 gcc_assert (!TREE_ADDRESSABLE (type
));
2350 args
[i
].initial_value
= args
[i
].value
2351 = expand_normal (args
[i
].tree_value
);
2353 mode
= TYPE_MODE (type
);
2354 if (mode
!= args
[i
].mode
)
2356 int unsignedp
= args
[i
].unsignedp
;
2358 = convert_modes (args
[i
].mode
, mode
,
2359 args
[i
].value
, args
[i
].unsignedp
);
2361 /* CSE will replace this only if it contains args[i].value
2362 pseudo, so convert it down to the declared mode using
2364 if (REG_P (args
[i
].value
)
2365 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
2366 && promote_mode (type
, mode
, &unsignedp
) != args
[i
].mode
)
2368 args
[i
].initial_value
2369 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
2370 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
2371 SUBREG_PROMOTED_SET (args
[i
].initial_value
, args
[i
].unsignedp
);
2377 /* Given the current state of MUST_PREALLOCATE and information about
2378 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
2379 compute and return the final value for MUST_PREALLOCATE. */
2382 finalize_must_preallocate (int must_preallocate
, int num_actuals
,
2383 struct arg_data
*args
, struct args_size
*args_size
)
2385 /* See if we have or want to preallocate stack space.
2387 If we would have to push a partially-in-regs parm
2388 before other stack parms, preallocate stack space instead.
2390 If the size of some parm is not a multiple of the required stack
2391 alignment, we must preallocate.
2393 If the total size of arguments that would otherwise create a copy in
2394 a temporary (such as a CALL) is more than half the total argument list
2395 size, preallocation is faster.
2397 Another reason to preallocate is if we have a machine (like the m88k)
2398 where stack alignment is required to be maintained between every
2399 pair of insns, not just when the call is made. However, we assume here
2400 that such machines either do not have push insns (and hence preallocation
2401 would occur anyway) or the problem is taken care of with
2404 if (! must_preallocate
)
2406 int partial_seen
= 0;
2407 poly_int64 copy_to_evaluate_size
= 0;
2410 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
2412 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
2414 else if (partial_seen
&& args
[i
].reg
== 0)
2415 must_preallocate
= 1;
2417 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
2418 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
2419 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
2420 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
2421 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
2422 copy_to_evaluate_size
2423 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
2426 if (maybe_ne (args_size
->constant
, 0)
2427 && maybe_ge (copy_to_evaluate_size
* 2, args_size
->constant
))
2428 must_preallocate
= 1;
2430 return must_preallocate
;
2433 /* If we preallocated stack space, compute the address of each argument
2434 and store it into the ARGS array.
2436 We need not ensure it is a valid memory address here; it will be
2437 validized when it is used.
2439 ARGBLOCK is an rtx for the address of the outgoing arguments. */
2442 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
2446 rtx arg_reg
= argblock
;
2448 poly_int64 arg_offset
= 0;
2450 if (GET_CODE (argblock
) == PLUS
)
2452 arg_reg
= XEXP (argblock
, 0);
2453 arg_offset
= rtx_to_poly_int64 (XEXP (argblock
, 1));
2456 for (i
= 0; i
< num_actuals
; i
++)
2458 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
2459 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
2461 unsigned int align
, boundary
;
2462 poly_uint64 units_on_stack
= 0;
2463 machine_mode partial_mode
= VOIDmode
;
2465 /* Skip this parm if it will not be passed on the stack. */
2466 if (! args
[i
].pass_on_stack
2468 && args
[i
].partial
== 0)
2471 if (TYPE_EMPTY_P (TREE_TYPE (args
[i
].tree_value
)))
2474 addr
= simplify_gen_binary (PLUS
, Pmode
, arg_reg
, offset
);
2475 addr
= plus_constant (Pmode
, addr
, arg_offset
);
2477 if (args
[i
].partial
!= 0)
2479 /* Only part of the parameter is being passed on the stack.
2480 Generate a simple memory reference of the correct size. */
2481 units_on_stack
= args
[i
].locate
.size
.constant
;
2482 poly_uint64 bits_on_stack
= units_on_stack
* BITS_PER_UNIT
;
2483 partial_mode
= int_mode_for_size (bits_on_stack
, 1).else_blk ();
2484 args
[i
].stack
= gen_rtx_MEM (partial_mode
, addr
);
2485 set_mem_size (args
[i
].stack
, units_on_stack
);
2489 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
2490 set_mem_attributes (args
[i
].stack
,
2491 TREE_TYPE (args
[i
].tree_value
), 1);
2493 align
= BITS_PER_UNIT
;
2494 boundary
= args
[i
].locate
.boundary
;
2495 poly_int64 offset_val
;
2496 if (args
[i
].locate
.where_pad
!= PAD_DOWNWARD
)
2498 else if (poly_int_rtx_p (offset
, &offset_val
))
2500 align
= least_bit_hwi (boundary
);
2501 unsigned int offset_align
2502 = known_alignment (offset_val
) * BITS_PER_UNIT
;
2503 if (offset_align
!= 0)
2504 align
= MIN (align
, offset_align
);
2506 set_mem_align (args
[i
].stack
, align
);
2508 addr
= simplify_gen_binary (PLUS
, Pmode
, arg_reg
, slot_offset
);
2509 addr
= plus_constant (Pmode
, addr
, arg_offset
);
2511 if (args
[i
].partial
!= 0)
2513 /* Only part of the parameter is being passed on the stack.
2514 Generate a simple memory reference of the correct size.
2516 args
[i
].stack_slot
= gen_rtx_MEM (partial_mode
, addr
);
2517 set_mem_size (args
[i
].stack_slot
, units_on_stack
);
2521 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
2522 set_mem_attributes (args
[i
].stack_slot
,
2523 TREE_TYPE (args
[i
].tree_value
), 1);
2525 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
2527 /* Function incoming arguments may overlap with sibling call
2528 outgoing arguments and we cannot allow reordering of reads
2529 from function arguments with stores to outgoing arguments
2530 of sibling calls. */
2531 set_mem_alias_set (args
[i
].stack
, 0);
2532 set_mem_alias_set (args
[i
].stack_slot
, 0);
2537 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
2538 in a call instruction.
2540 FNDECL is the tree node for the target function. For an indirect call
2541 FNDECL will be NULL_TREE.
2543 ADDR is the operand 0 of CALL_EXPR for this call. */
2546 rtx_for_function_call (tree fndecl
, tree addr
)
2550 /* Get the function to call, in the form of RTL. */
2553 if (!TREE_USED (fndecl
) && fndecl
!= current_function_decl
)
2554 TREE_USED (fndecl
) = 1;
2556 /* Get a SYMBOL_REF rtx for the function address. */
2557 funexp
= XEXP (DECL_RTL (fndecl
), 0);
2560 /* Generate an rtx (probably a pseudo-register) for the address. */
2563 funexp
= expand_normal (addr
);
2564 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
2569 /* Return the static chain for this function, if any. */
2572 rtx_for_static_chain (const_tree fndecl_or_type
, bool incoming_p
)
2574 if (DECL_P (fndecl_or_type
) && !DECL_STATIC_CHAIN (fndecl_or_type
))
2577 return targetm
.calls
.static_chain (fndecl_or_type
, incoming_p
);
2580 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
2583 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
2584 or NULL_RTX if none has been scanned yet. */
2585 rtx_insn
*scan_start
;
2586 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
2587 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
2588 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
2589 with fixed offset, or PC if this is with variable or unknown offset. */
2591 } internal_arg_pointer_exp_state
;
2593 static rtx
internal_arg_pointer_based_exp (const_rtx
, bool);
2595 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
2596 the tail call sequence, starting with first insn that hasn't been
2597 scanned yet, and note for each pseudo on the LHS whether it is based
2598 on crtl->args.internal_arg_pointer or not, and what offset from that
2599 that pointer it has. */
2602 internal_arg_pointer_based_exp_scan (void)
2604 rtx_insn
*insn
, *scan_start
= internal_arg_pointer_exp_state
.scan_start
;
2606 if (scan_start
== NULL_RTX
)
2607 insn
= get_insns ();
2609 insn
= NEXT_INSN (scan_start
);
2613 rtx set
= single_set (insn
);
2614 if (set
&& REG_P (SET_DEST (set
)) && !HARD_REGISTER_P (SET_DEST (set
)))
2617 unsigned int idx
= REGNO (SET_DEST (set
)) - FIRST_PSEUDO_REGISTER
;
2618 /* Punt on pseudos set multiple times. */
2619 if (idx
< internal_arg_pointer_exp_state
.cache
.length ()
2620 && (internal_arg_pointer_exp_state
.cache
[idx
]
2624 val
= internal_arg_pointer_based_exp (SET_SRC (set
), false);
2625 if (val
!= NULL_RTX
)
2627 if (idx
>= internal_arg_pointer_exp_state
.cache
.length ())
2628 internal_arg_pointer_exp_state
.cache
2629 .safe_grow_cleared (idx
+ 1);
2630 internal_arg_pointer_exp_state
.cache
[idx
] = val
;
2633 if (NEXT_INSN (insn
) == NULL_RTX
)
2635 insn
= NEXT_INSN (insn
);
2638 internal_arg_pointer_exp_state
.scan_start
= scan_start
;
2641 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
2642 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
2643 it with fixed offset, or PC if this is with variable or unknown offset.
2644 TOPLEVEL is true if the function is invoked at the topmost level. */
2647 internal_arg_pointer_based_exp (const_rtx rtl
, bool toplevel
)
2649 if (CONSTANT_P (rtl
))
2652 if (rtl
== crtl
->args
.internal_arg_pointer
)
2655 if (REG_P (rtl
) && HARD_REGISTER_P (rtl
))
2659 if (GET_CODE (rtl
) == PLUS
&& poly_int_rtx_p (XEXP (rtl
, 1), &offset
))
2661 rtx val
= internal_arg_pointer_based_exp (XEXP (rtl
, 0), toplevel
);
2662 if (val
== NULL_RTX
|| val
== pc_rtx
)
2664 return plus_constant (Pmode
, val
, offset
);
2667 /* When called at the topmost level, scan pseudo assignments in between the
2668 last scanned instruction in the tail call sequence and the latest insn
2669 in that sequence. */
2671 internal_arg_pointer_based_exp_scan ();
2675 unsigned int idx
= REGNO (rtl
) - FIRST_PSEUDO_REGISTER
;
2676 if (idx
< internal_arg_pointer_exp_state
.cache
.length ())
2677 return internal_arg_pointer_exp_state
.cache
[idx
];
2682 subrtx_iterator::array_type array
;
2683 FOR_EACH_SUBRTX (iter
, array
, rtl
, NONCONST
)
2685 const_rtx x
= *iter
;
2686 if (REG_P (x
) && internal_arg_pointer_based_exp (x
, false) != NULL_RTX
)
2689 iter
.skip_subrtxes ();
2695 /* Return true if SIZE bytes starting from address ADDR might overlap an
2696 already-clobbered argument area. This function is used to determine
2697 if we should give up a sibcall. */
2700 mem_might_overlap_already_clobbered_arg_p (rtx addr
, poly_uint64 size
)
2703 unsigned HOST_WIDE_INT start
, end
;
2706 if (bitmap_empty_p (stored_args_map
)
2707 && stored_args_watermark
== HOST_WIDE_INT_M1U
)
2709 val
= internal_arg_pointer_based_exp (addr
, true);
2710 if (val
== NULL_RTX
)
2712 else if (!poly_int_rtx_p (val
, &i
))
2715 if (known_eq (size
, 0U))
2718 if (STACK_GROWS_DOWNWARD
)
2719 i
-= crtl
->args
.pretend_args_size
;
2721 i
+= crtl
->args
.pretend_args_size
;
2723 if (ARGS_GROW_DOWNWARD
)
2726 /* We can ignore any references to the function's pretend args,
2727 which at this point would manifest as negative values of I. */
2728 if (known_le (i
, 0) && known_le (size
, poly_uint64 (-i
)))
2731 start
= maybe_lt (i
, 0) ? 0 : constant_lower_bound (i
);
2732 if (!(i
+ size
).is_constant (&end
))
2733 end
= HOST_WIDE_INT_M1U
;
2735 if (end
> stored_args_watermark
)
2738 end
= MIN (end
, SBITMAP_SIZE (stored_args_map
));
2739 for (unsigned HOST_WIDE_INT k
= start
; k
< end
; ++k
)
2740 if (bitmap_bit_p (stored_args_map
, k
))
2746 /* Do the register loads required for any wholly-register parms or any
2747 parms which are passed both on the stack and in a register. Their
2748 expressions were already evaluated.
2750 Mark all register-parms as living through the call, putting these USE
2751 insns in the CALL_INSN_FUNCTION_USAGE field.
2753 When IS_SIBCALL, perform the check_sibcall_argument_overlap
2754 checking, setting *SIBCALL_FAILURE if appropriate. */
2757 load_register_parameters (struct arg_data
*args
, int num_actuals
,
2758 rtx
*call_fusage
, int flags
, int is_sibcall
,
2759 int *sibcall_failure
)
2763 for (i
= 0; i
< num_actuals
; i
++)
2765 rtx reg
= ((flags
& ECF_SIBCALL
)
2766 ? args
[i
].tail_call_reg
: args
[i
].reg
);
2769 int partial
= args
[i
].partial
;
2771 poly_int64 size
= 0;
2772 HOST_WIDE_INT const_size
= 0;
2773 rtx_insn
*before_arg
= get_last_insn ();
2774 tree type
= TREE_TYPE (args
[i
].tree_value
);
2775 if ((TREE_CODE (type
) == UNION_TYPE
2776 || TREE_CODE (type
) == RECORD_TYPE
)
2777 && TYPE_TRANSPARENT_AGGR (type
))
2778 type
= TREE_TYPE (first_field (type
));
2779 /* Set non-negative if we must move a word at a time, even if
2780 just one word (e.g, partial == 4 && mode == DFmode). Set
2781 to -1 if we just use a normal move insn. This value can be
2782 zero if the argument is a zero size structure. */
2784 if (GET_CODE (reg
) == PARALLEL
)
2788 gcc_assert (partial
% UNITS_PER_WORD
== 0);
2789 nregs
= partial
/ UNITS_PER_WORD
;
2791 else if (TYPE_MODE (type
) == BLKmode
)
2793 /* Variable-sized parameters should be described by a
2794 PARALLEL instead. */
2795 const_size
= int_size_in_bytes (type
);
2796 gcc_assert (const_size
>= 0);
2797 nregs
= (const_size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
2801 size
= GET_MODE_SIZE (args
[i
].mode
);
2803 /* Handle calls that pass values in multiple non-contiguous
2804 locations. The Irix 6 ABI has examples of this. */
2806 if (GET_CODE (reg
) == PARALLEL
)
2807 emit_group_move (reg
, args
[i
].parallel_value
);
2809 /* If simple case, just do move. If normal partial, store_one_arg
2810 has already loaded the register for us. In all other cases,
2811 load the register(s) from memory. */
2813 else if (nregs
== -1)
2815 emit_move_insn (reg
, args
[i
].value
);
2816 #ifdef BLOCK_REG_PADDING
2817 /* Handle case where we have a value that needs shifting
2818 up to the msb. eg. a QImode value and we're padding
2819 upward on a BYTES_BIG_ENDIAN machine. */
2820 if (args
[i
].locate
.where_pad
2821 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
))
2823 gcc_checking_assert (ordered_p (size
, UNITS_PER_WORD
));
2824 if (maybe_lt (size
, UNITS_PER_WORD
))
2828 = (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2830 /* Assigning REG here rather than a temp makes
2831 CALL_FUSAGE report the whole reg as used.
2832 Strictly speaking, the call only uses SIZE
2833 bytes at the msb end, but it doesn't seem worth
2834 generating rtl to say that. */
2835 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
2836 x
= expand_shift (LSHIFT_EXPR
, word_mode
,
2837 reg
, shift
, reg
, 1);
2839 emit_move_insn (reg
, x
);
2845 /* If we have pre-computed the values to put in the registers in
2846 the case of non-aligned structures, copy them in now. */
2848 else if (args
[i
].n_aligned_regs
!= 0)
2849 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
2850 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
2851 args
[i
].aligned_regs
[j
]);
2853 else if (partial
== 0 || args
[i
].pass_on_stack
)
2855 /* SIZE and CONST_SIZE are 0 for partial arguments and
2856 the size of a BLKmode type otherwise. */
2857 gcc_checking_assert (known_eq (size
, const_size
));
2858 rtx mem
= validize_mem (copy_rtx (args
[i
].value
));
2860 /* Check for overlap with already clobbered argument area,
2861 providing that this has non-zero size. */
2864 && (mem_might_overlap_already_clobbered_arg_p
2865 (XEXP (args
[i
].value
, 0), const_size
)))
2866 *sibcall_failure
= 1;
2868 if (const_size
% UNITS_PER_WORD
== 0
2869 || MEM_ALIGN (mem
) % BITS_PER_WORD
== 0)
2870 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
2874 move_block_to_reg (REGNO (reg
), mem
, nregs
- 1,
2876 rtx dest
= gen_rtx_REG (word_mode
, REGNO (reg
) + nregs
- 1);
2877 unsigned int bitoff
= (nregs
- 1) * BITS_PER_WORD
;
2878 unsigned int bitsize
= const_size
* BITS_PER_UNIT
- bitoff
;
2879 rtx x
= extract_bit_field (mem
, bitsize
, bitoff
, 1, dest
,
2880 word_mode
, word_mode
, false,
2882 if (BYTES_BIG_ENDIAN
)
2883 x
= expand_shift (LSHIFT_EXPR
, word_mode
, x
,
2884 BITS_PER_WORD
- bitsize
, dest
, 1);
2886 emit_move_insn (dest
, x
);
2889 /* Handle a BLKmode that needs shifting. */
2890 if (nregs
== 1 && const_size
< UNITS_PER_WORD
2891 #ifdef BLOCK_REG_PADDING
2892 && args
[i
].locate
.where_pad
== PAD_DOWNWARD
2898 rtx dest
= gen_rtx_REG (word_mode
, REGNO (reg
));
2899 int shift
= (UNITS_PER_WORD
- const_size
) * BITS_PER_UNIT
;
2900 enum tree_code dir
= (BYTES_BIG_ENDIAN
2901 ? RSHIFT_EXPR
: LSHIFT_EXPR
);
2904 x
= expand_shift (dir
, word_mode
, dest
, shift
, dest
, 1);
2906 emit_move_insn (dest
, x
);
2910 /* When a parameter is a block, and perhaps in other cases, it is
2911 possible that it did a load from an argument slot that was
2912 already clobbered. */
2914 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
2915 *sibcall_failure
= 1;
2917 /* Handle calls that pass values in multiple non-contiguous
2918 locations. The Irix 6 ABI has examples of this. */
2919 if (GET_CODE (reg
) == PARALLEL
)
2920 use_group_regs (call_fusage
, reg
);
2921 else if (nregs
== -1)
2922 use_reg_mode (call_fusage
, reg
, TYPE_MODE (type
));
2924 use_regs (call_fusage
, REGNO (reg
), nregs
);
2929 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2930 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2931 bytes, then we would need to push some additional bytes to pad the
2932 arguments. So, we try to compute an adjust to the stack pointer for an
2933 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2934 bytes. Then, when the arguments are pushed the stack will be perfectly
2937 Return true if this optimization is possible, storing the adjustment
2938 in ADJUSTMENT_OUT and setting ARGS_SIZE->CONSTANT to the number of
2939 bytes that should be popped after the call. */
2942 combine_pending_stack_adjustment_and_call (poly_int64_pod
*adjustment_out
,
2943 poly_int64 unadjusted_args_size
,
2944 struct args_size
*args_size
,
2945 unsigned int preferred_unit_stack_boundary
)
2947 /* The number of bytes to pop so that the stack will be
2948 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2949 poly_int64 adjustment
;
2950 /* The alignment of the stack after the arguments are pushed, if we
2951 just pushed the arguments without adjust the stack here. */
2952 unsigned HOST_WIDE_INT unadjusted_alignment
;
2954 if (!known_misalignment (stack_pointer_delta
+ unadjusted_args_size
,
2955 preferred_unit_stack_boundary
,
2956 &unadjusted_alignment
))
2959 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2960 as possible -- leaving just enough left to cancel out the
2961 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2962 PENDING_STACK_ADJUST is non-negative, and congruent to
2963 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2965 /* Begin by trying to pop all the bytes. */
2966 unsigned HOST_WIDE_INT tmp_misalignment
;
2967 if (!known_misalignment (pending_stack_adjust
,
2968 preferred_unit_stack_boundary
,
2971 unadjusted_alignment
-= tmp_misalignment
;
2972 adjustment
= pending_stack_adjust
;
2973 /* Push enough additional bytes that the stack will be aligned
2974 after the arguments are pushed. */
2975 if (preferred_unit_stack_boundary
> 1 && unadjusted_alignment
)
2976 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
2978 /* We need to know whether the adjusted argument size
2979 (UNADJUSTED_ARGS_SIZE - ADJUSTMENT) constitutes an allocation
2980 or a deallocation. */
2981 if (!ordered_p (adjustment
, unadjusted_args_size
))
2984 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2985 bytes after the call. The right number is the entire
2986 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2987 by the arguments in the first place. */
2989 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
2991 *adjustment_out
= adjustment
;
2995 /* Scan X expression if it does not dereference any argument slots
2996 we already clobbered by tail call arguments (as noted in stored_args_map
2998 Return nonzero if X expression dereferences such argument slots,
3002 check_sibcall_argument_overlap_1 (rtx x
)
3011 code
= GET_CODE (x
);
3013 /* We need not check the operands of the CALL expression itself. */
3018 return (mem_might_overlap_already_clobbered_arg_p
3019 (XEXP (x
, 0), GET_MODE_SIZE (GET_MODE (x
))));
3021 /* Scan all subexpressions. */
3022 fmt
= GET_RTX_FORMAT (code
);
3023 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
3027 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
3030 else if (*fmt
== 'E')
3032 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
3033 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
3040 /* Scan sequence after INSN if it does not dereference any argument slots
3041 we already clobbered by tail call arguments (as noted in stored_args_map
3042 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
3043 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
3044 should be 0). Return nonzero if sequence after INSN dereferences such argument
3045 slots, zero otherwise. */
3048 check_sibcall_argument_overlap (rtx_insn
*insn
, struct arg_data
*arg
,
3049 int mark_stored_args_map
)
3051 poly_uint64 low
, high
;
3052 unsigned HOST_WIDE_INT const_low
, const_high
;
3054 if (insn
== NULL_RTX
)
3055 insn
= get_insns ();
3057 insn
= NEXT_INSN (insn
);
3059 for (; insn
; insn
= NEXT_INSN (insn
))
3061 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
3064 if (mark_stored_args_map
)
3066 if (ARGS_GROW_DOWNWARD
)
3067 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
3069 low
= arg
->locate
.slot_offset
.constant
;
3070 high
= low
+ arg
->locate
.size
.constant
;
3072 const_low
= constant_lower_bound (low
);
3073 if (high
.is_constant (&const_high
))
3074 for (unsigned HOST_WIDE_INT i
= const_low
; i
< const_high
; ++i
)
3075 bitmap_set_bit (stored_args_map
, i
);
3077 stored_args_watermark
= MIN (stored_args_watermark
, const_low
);
3079 return insn
!= NULL_RTX
;
3082 /* Given that a function returns a value of mode MODE at the most
3083 significant end of hard register VALUE, shift VALUE left or right
3084 as specified by LEFT_P. Return true if some action was needed. */
3087 shift_return_value (machine_mode mode
, bool left_p
, rtx value
)
3089 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
3090 machine_mode value_mode
= GET_MODE (value
);
3091 poly_int64 shift
= GET_MODE_BITSIZE (value_mode
) - GET_MODE_BITSIZE (mode
);
3093 if (known_eq (shift
, 0))
3096 /* Use ashr rather than lshr for right shifts. This is for the benefit
3097 of the MIPS port, which requires SImode values to be sign-extended
3098 when stored in 64-bit registers. */
3099 if (!force_expand_binop (value_mode
, left_p
? ashl_optab
: ashr_optab
,
3100 value
, gen_int_shift_amount (value_mode
, shift
),
3101 value
, 1, OPTAB_WIDEN
))
3106 /* If X is a likely-spilled register value, copy it to a pseudo
3107 register and return that register. Return X otherwise. */
3110 avoid_likely_spilled_reg (rtx x
)
3115 && HARD_REGISTER_P (x
)
3116 && targetm
.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x
))))
3118 /* Make sure that we generate a REG rather than a CONCAT.
3119 Moves into CONCATs can need nontrivial instructions,
3120 and the whole point of this function is to avoid
3121 using the hard register directly in such a situation. */
3122 generating_concat_p
= 0;
3123 new_rtx
= gen_reg_rtx (GET_MODE (x
));
3124 generating_concat_p
= 1;
3125 emit_move_insn (new_rtx
, x
);
3131 /* Helper function for expand_call.
3132 Return false is EXP is not implementable as a sibling call. */
3135 can_implement_as_sibling_call_p (tree exp
,
3136 rtx structure_value_addr
,
3138 int reg_parm_stack_space ATTRIBUTE_UNUSED
,
3142 const args_size
&args_size
)
3144 if (!targetm
.have_sibcall_epilogue ())
3146 maybe_complain_about_tail_call
3148 "machine description does not have"
3149 " a sibcall_epilogue instruction pattern");
3153 /* Doing sibling call optimization needs some work, since
3154 structure_value_addr can be allocated on the stack.
3155 It does not seem worth the effort since few optimizable
3156 sibling calls will return a structure. */
3157 if (structure_value_addr
!= NULL_RTX
)
3159 maybe_complain_about_tail_call (exp
, "callee returns a structure");
3163 #ifdef REG_PARM_STACK_SPACE
3164 /* If outgoing reg parm stack space changes, we cannot do sibcall. */
3165 if (OUTGOING_REG_PARM_STACK_SPACE (funtype
)
3166 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl
))
3167 || (reg_parm_stack_space
!= REG_PARM_STACK_SPACE (current_function_decl
)))
3169 maybe_complain_about_tail_call (exp
,
3170 "inconsistent size of stack space"
3171 " allocated for arguments which are"
3172 " passed in registers");
3177 /* Check whether the target is able to optimize the call
3179 if (!targetm
.function_ok_for_sibcall (fndecl
, exp
))
3181 maybe_complain_about_tail_call (exp
,
3182 "target is not able to optimize the"
3183 " call into a sibling call");
3187 /* Functions that do not return exactly once may not be sibcall
3189 if (flags
& ECF_RETURNS_TWICE
)
3191 maybe_complain_about_tail_call (exp
, "callee returns twice");
3194 if (flags
& ECF_NORETURN
)
3196 maybe_complain_about_tail_call (exp
, "callee does not return");
3200 if (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
))))
3202 maybe_complain_about_tail_call (exp
, "volatile function type");
3206 /* If the called function is nested in the current one, it might access
3207 some of the caller's arguments, but could clobber them beforehand if
3208 the argument areas are shared. */
3209 if (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
3211 maybe_complain_about_tail_call (exp
, "nested function");
3215 /* If this function requires more stack slots than the current
3216 function, we cannot change it into a sibling call.
3217 crtl->args.pretend_args_size is not part of the
3218 stack allocated by our caller. */
3219 if (maybe_gt (args_size
.constant
,
3220 crtl
->args
.size
- crtl
->args
.pretend_args_size
))
3222 maybe_complain_about_tail_call (exp
,
3223 "callee required more stack slots"
3224 " than the caller");
3228 /* If the callee pops its own arguments, then it must pop exactly
3229 the same number of arguments as the current function. */
3230 if (maybe_ne (targetm
.calls
.return_pops_args (fndecl
, funtype
,
3231 args_size
.constant
),
3232 targetm
.calls
.return_pops_args (current_function_decl
,
3234 (current_function_decl
),
3237 maybe_complain_about_tail_call (exp
,
3238 "inconsistent number of"
3239 " popped arguments");
3243 if (!lang_hooks
.decls
.ok_for_sibcall (fndecl
))
3245 maybe_complain_about_tail_call (exp
, "frontend does not support"
3250 /* All checks passed. */
3254 /* Update stack alignment when the parameter is passed in the stack
3255 since the outgoing parameter requires extra alignment on the calling
3259 update_stack_alignment_for_call (struct locate_and_pad_arg_data
*locate
)
3261 if (crtl
->stack_alignment_needed
< locate
->boundary
)
3262 crtl
->stack_alignment_needed
= locate
->boundary
;
3263 if (crtl
->preferred_stack_boundary
< locate
->boundary
)
3264 crtl
->preferred_stack_boundary
= locate
->boundary
;
3267 /* Generate all the code for a CALL_EXPR exp
3268 and return an rtx for its value.
3269 Store the value in TARGET (specified as an rtx) if convenient.
3270 If the value is stored in TARGET then TARGET is returned.
3271 If IGNORE is nonzero, then we ignore the value of the function call. */
3274 expand_call (tree exp
, rtx target
, int ignore
)
3276 /* Nonzero if we are currently expanding a call. */
3277 static int currently_expanding_call
= 0;
3279 /* RTX for the function to be called. */
3281 /* Sequence of insns to perform a normal "call". */
3282 rtx_insn
*normal_call_insns
= NULL
;
3283 /* Sequence of insns to perform a tail "call". */
3284 rtx_insn
*tail_call_insns
= NULL
;
3285 /* Data type of the function. */
3287 tree type_arg_types
;
3289 /* Declaration of the function being called,
3290 or 0 if the function is computed (not known by name). */
3292 /* The type of the function being called. */
3294 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
3295 bool must_tail_call
= CALL_EXPR_MUST_TAIL_CALL (exp
);
3298 /* Register in which non-BLKmode value will be returned,
3299 or 0 if no value or if value is BLKmode. */
3301 /* Address where we should return a BLKmode value;
3302 0 if value not BLKmode. */
3303 rtx structure_value_addr
= 0;
3304 /* Nonzero if that address is being passed by treating it as
3305 an extra, implicit first parameter. Otherwise,
3306 it is passed by being copied directly into struct_value_rtx. */
3307 int structure_value_addr_parm
= 0;
3308 /* Holds the value of implicit argument for the struct value. */
3309 tree structure_value_addr_value
= NULL_TREE
;
3310 /* Size of aggregate value wanted, or zero if none wanted
3311 or if we are using the non-reentrant PCC calling convention
3312 or expecting the value in registers. */
3313 poly_int64 struct_value_size
= 0;
3314 /* Nonzero if called function returns an aggregate in memory PCC style,
3315 by returning the address of where to find it. */
3316 int pcc_struct_value
= 0;
3317 rtx struct_value
= 0;
3319 /* Number of actual parameters in this call, including struct value addr. */
3321 /* Number of named args. Args after this are anonymous ones
3322 and they must all go on the stack. */
3324 /* Number of complex actual arguments that need to be split. */
3325 int num_complex_actuals
= 0;
3327 /* Vector of information about each argument.
3328 Arguments are numbered in the order they will be pushed,
3329 not the order they are written. */
3330 struct arg_data
*args
;
3332 /* Total size in bytes of all the stack-parms scanned so far. */
3333 struct args_size args_size
;
3334 struct args_size adjusted_args_size
;
3335 /* Size of arguments before any adjustments (such as rounding). */
3336 poly_int64 unadjusted_args_size
;
3337 /* Data on reg parms scanned so far. */
3338 CUMULATIVE_ARGS args_so_far_v
;
3339 cumulative_args_t args_so_far
;
3340 /* Nonzero if a reg parm has been scanned. */
3342 /* Nonzero if this is an indirect function call. */
3344 /* Nonzero if we must avoid push-insns in the args for this call.
3345 If stack space is allocated for register parameters, but not by the
3346 caller, then it is preallocated in the fixed part of the stack frame.
3347 So the entire argument block must then be preallocated (i.e., we
3348 ignore PUSH_ROUNDING in that case). */
3350 int must_preallocate
= !PUSH_ARGS
;
3352 /* Size of the stack reserved for parameter registers. */
3353 int reg_parm_stack_space
= 0;
3355 /* Address of space preallocated for stack parms
3356 (on machines that lack push insns), or 0 if space not preallocated. */
3359 /* Mask of ECF_ and ERF_ flags. */
3361 int return_flags
= 0;
3362 #ifdef REG_PARM_STACK_SPACE
3363 /* Define the boundary of the register parm stack space that needs to be
3365 int low_to_save
, high_to_save
;
3366 rtx save_area
= 0; /* Place that it is saved */
3369 unsigned int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3370 char *initial_stack_usage_map
= stack_usage_map
;
3371 unsigned HOST_WIDE_INT initial_stack_usage_watermark
= stack_usage_watermark
;
3372 char *stack_usage_map_buf
= NULL
;
3374 poly_int64 old_stack_allocated
;
3376 /* State variables to track stack modifications. */
3377 rtx old_stack_level
= 0;
3378 int old_stack_arg_under_construction
= 0;
3379 poly_int64 old_pending_adj
= 0;
3380 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3382 /* Some stack pointer alterations we make are performed via
3383 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
3384 which we then also need to save/restore along the way. */
3385 poly_int64 old_stack_pointer_delta
= 0;
3388 tree addr
= CALL_EXPR_FN (exp
);
3390 /* The alignment of the stack, in bits. */
3391 unsigned HOST_WIDE_INT preferred_stack_boundary
;
3392 /* The alignment of the stack, in bytes. */
3393 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
3394 /* The static chain value to use for this call. */
3395 rtx static_chain_value
;
3396 /* See if this is "nothrow" function call. */
3397 if (TREE_NOTHROW (exp
))
3398 flags
|= ECF_NOTHROW
;
3400 /* See if we can find a DECL-node for the actual function, and get the
3401 function attributes (flags) from the function decl or type node. */
3402 fndecl
= get_callee_fndecl (exp
);
3405 fntype
= TREE_TYPE (fndecl
);
3406 flags
|= flags_from_decl_or_type (fndecl
);
3407 return_flags
|= decl_return_flags (fndecl
);
3411 fntype
= TREE_TYPE (TREE_TYPE (addr
));
3412 flags
|= flags_from_decl_or_type (fntype
);
3413 if (CALL_EXPR_BY_DESCRIPTOR (exp
))
3414 flags
|= ECF_BY_DESCRIPTOR
;
3416 rettype
= TREE_TYPE (exp
);
3418 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
3420 /* Warn if this value is an aggregate type,
3421 regardless of which calling convention we are using for it. */
3422 if (AGGREGATE_TYPE_P (rettype
))
3423 warning (OPT_Waggregate_return
, "function call has aggregate value");
3425 /* If the result of a non looping pure or const function call is
3426 ignored (or void), and none of its arguments are volatile, we can
3427 avoid expanding the call and just evaluate the arguments for
3429 if ((flags
& (ECF_CONST
| ECF_PURE
))
3430 && (!(flags
& ECF_LOOPING_CONST_OR_PURE
))
3431 && (ignore
|| target
== const0_rtx
3432 || TYPE_MODE (rettype
) == VOIDmode
))
3434 bool volatilep
= false;
3436 call_expr_arg_iterator iter
;
3438 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3439 if (TREE_THIS_VOLATILE (arg
))
3447 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3448 expand_expr (arg
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
3453 #ifdef REG_PARM_STACK_SPACE
3454 reg_parm_stack_space
= REG_PARM_STACK_SPACE (!fndecl
? fntype
: fndecl
);
3457 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
3458 && reg_parm_stack_space
> 0 && PUSH_ARGS
)
3459 must_preallocate
= 1;
3461 /* Set up a place to return a structure. */
3463 /* Cater to broken compilers. */
3464 if (aggregate_value_p (exp
, fntype
))
3466 /* This call returns a big structure. */
3467 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
3469 #ifdef PCC_STATIC_STRUCT_RETURN
3471 pcc_struct_value
= 1;
3473 #else /* not PCC_STATIC_STRUCT_RETURN */
3475 if (!poly_int_tree_p (TYPE_SIZE_UNIT (rettype
), &struct_value_size
))
3476 struct_value_size
= -1;
3478 /* Even if it is semantically safe to use the target as the return
3479 slot, it may be not sufficiently aligned for the return type. */
3480 if (CALL_EXPR_RETURN_SLOT_OPT (exp
)
3483 /* If rettype is addressable, we may not create a temporary.
3484 If target is properly aligned at runtime and the compiler
3485 just doesn't know about it, it will work fine, otherwise it
3487 && (TREE_ADDRESSABLE (rettype
)
3488 || !(MEM_ALIGN (target
) < TYPE_ALIGN (rettype
)
3489 && targetm
.slow_unaligned_access (TYPE_MODE (rettype
),
3490 MEM_ALIGN (target
)))))
3491 structure_value_addr
= XEXP (target
, 0);
3494 /* For variable-sized objects, we must be called with a target
3495 specified. If we were to allocate space on the stack here,
3496 we would have no way of knowing when to free it. */
3497 rtx d
= assign_temp (rettype
, 1, 1);
3498 structure_value_addr
= XEXP (d
, 0);
3502 #endif /* not PCC_STATIC_STRUCT_RETURN */
3505 /* Figure out the amount to which the stack should be aligned. */
3506 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3509 struct cgraph_rtl_info
*i
= cgraph_node::rtl_info (fndecl
);
3510 /* Without automatic stack alignment, we can't increase preferred
3511 stack boundary. With automatic stack alignment, it is
3512 unnecessary since unless we can guarantee that all callers will
3513 align the outgoing stack properly, callee has to align its
3516 && i
->preferred_incoming_stack_boundary
3517 && i
->preferred_incoming_stack_boundary
< preferred_stack_boundary
)
3518 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
3521 /* Operand 0 is a pointer-to-function; get the type of the function. */
3522 funtype
= TREE_TYPE (addr
);
3523 gcc_assert (POINTER_TYPE_P (funtype
));
3524 funtype
= TREE_TYPE (funtype
);
3526 /* Count whether there are actual complex arguments that need to be split
3527 into their real and imaginary parts. Munge the type_arg_types
3528 appropriately here as well. */
3529 if (targetm
.calls
.split_complex_arg
)
3531 call_expr_arg_iterator iter
;
3533 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3535 tree type
= TREE_TYPE (arg
);
3536 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
3537 && targetm
.calls
.split_complex_arg (type
))
3538 num_complex_actuals
++;
3540 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
3543 type_arg_types
= TYPE_ARG_TYPES (funtype
);
3545 if (flags
& ECF_MAY_BE_ALLOCA
)
3546 cfun
->calls_alloca
= 1;
3548 /* If struct_value_rtx is 0, it means pass the address
3549 as if it were an extra parameter. Put the argument expression
3550 in structure_value_addr_value. */
3551 if (structure_value_addr
&& struct_value
== 0)
3553 /* If structure_value_addr is a REG other than
3554 virtual_outgoing_args_rtx, we can use always use it. If it
3555 is not a REG, we must always copy it into a register.
3556 If it is virtual_outgoing_args_rtx, we must copy it to another
3557 register in some cases. */
3558 rtx temp
= (!REG_P (structure_value_addr
)
3559 || (ACCUMULATE_OUTGOING_ARGS
3560 && stack_arg_under_construction
3561 && structure_value_addr
== virtual_outgoing_args_rtx
)
3562 ? copy_addr_to_reg (convert_memory_address
3563 (Pmode
, structure_value_addr
))
3564 : structure_value_addr
);
3566 structure_value_addr_value
=
3567 make_tree (build_pointer_type (TREE_TYPE (funtype
)), temp
);
3568 structure_value_addr_parm
= 1;
3571 /* Count the arguments and set NUM_ACTUALS. */
3573 call_expr_nargs (exp
) + num_complex_actuals
+ structure_value_addr_parm
;
3575 /* Compute number of named args.
3576 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
3578 if (type_arg_types
!= 0)
3580 = (list_length (type_arg_types
)
3581 /* Count the struct value address, if it is passed as a parm. */
3582 + structure_value_addr_parm
);
3584 /* If we know nothing, treat all args as named. */
3585 n_named_args
= num_actuals
;
3587 /* Start updating where the next arg would go.
3589 On some machines (such as the PA) indirect calls have a different
3590 calling convention than normal calls. The fourth argument in
3591 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
3593 INIT_CUMULATIVE_ARGS (args_so_far_v
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
3594 args_so_far
= pack_cumulative_args (&args_so_far_v
);
3596 /* Now possibly adjust the number of named args.
3597 Normally, don't include the last named arg if anonymous args follow.
3598 We do include the last named arg if
3599 targetm.calls.strict_argument_naming() returns nonzero.
3600 (If no anonymous args follow, the result of list_length is actually
3601 one too large. This is harmless.)
3603 If targetm.calls.pretend_outgoing_varargs_named() returns
3604 nonzero, and targetm.calls.strict_argument_naming() returns zero,
3605 this machine will be able to place unnamed args that were passed
3606 in registers into the stack. So treat all args as named. This
3607 allows the insns emitting for a specific argument list to be
3608 independent of the function declaration.
3610 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
3611 we do not have any reliable way to pass unnamed args in
3612 registers, so we must force them into memory. */
3614 if (type_arg_types
!= 0
3615 && targetm
.calls
.strict_argument_naming (args_so_far
))
3617 else if (type_arg_types
!= 0
3618 && ! targetm
.calls
.pretend_outgoing_varargs_named (args_so_far
))
3619 /* Don't include the last named arg. */
3622 /* Treat all args as named. */
3623 n_named_args
= num_actuals
;
3625 /* Make a vector to hold all the information about each arg. */
3626 args
= XCNEWVEC (struct arg_data
, num_actuals
);
3628 /* Build up entries in the ARGS array, compute the size of the
3629 arguments into ARGS_SIZE, etc. */
3630 initialize_argument_information (num_actuals
, args
, &args_size
,
3632 structure_value_addr_value
, fndecl
, fntype
,
3633 args_so_far
, reg_parm_stack_space
,
3634 &old_stack_level
, &old_pending_adj
,
3635 &must_preallocate
, &flags
,
3636 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
3639 must_preallocate
= 1;
3641 /* Now make final decision about preallocating stack space. */
3642 must_preallocate
= finalize_must_preallocate (must_preallocate
,
3646 /* If the structure value address will reference the stack pointer, we
3647 must stabilize it. We don't need to do this if we know that we are
3648 not going to adjust the stack pointer in processing this call. */
3650 if (structure_value_addr
3651 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
3652 || reg_mentioned_p (virtual_outgoing_args_rtx
,
3653 structure_value_addr
))
3655 || (!ACCUMULATE_OUTGOING_ARGS
3656 && maybe_ne (args_size
.constant
, 0))))
3657 structure_value_addr
= copy_to_reg (structure_value_addr
);
3659 /* Tail calls can make things harder to debug, and we've traditionally
3660 pushed these optimizations into -O2. Don't try if we're already
3661 expanding a call, as that means we're an argument. Don't try if
3662 there's cleanups, as we know there's code to follow the call. */
3663 if (currently_expanding_call
++ != 0
3664 || (!flag_optimize_sibling_calls
&& !CALL_FROM_THUNK_P (exp
))
3666 || dbg_cnt (tail_call
) == false)
3669 /* Workaround buggy C/C++ wrappers around Fortran routines with
3670 character(len=constant) arguments if the hidden string length arguments
3671 are passed on the stack; if the callers forget to pass those arguments,
3672 attempting to tail call in such routines leads to stack corruption.
3673 Avoid tail calls in functions where at least one such hidden string
3674 length argument is passed (partially or fully) on the stack in the
3675 caller and the callee needs to pass any arguments on the stack.
3677 if (try_tail_call
&& maybe_ne (args_size
.constant
, 0))
3678 for (tree arg
= DECL_ARGUMENTS (current_function_decl
);
3679 arg
; arg
= DECL_CHAIN (arg
))
3680 if (DECL_HIDDEN_STRING_LENGTH (arg
) && DECL_INCOMING_RTL (arg
))
3682 subrtx_iterator::array_type array
;
3683 FOR_EACH_SUBRTX (iter
, array
, DECL_INCOMING_RTL (arg
), NONCONST
)
3691 /* If the user has marked the function as requiring tail-call
3692 optimization, attempt it. */
3696 /* Rest of purposes for tail call optimizations to fail. */
3698 try_tail_call
= can_implement_as_sibling_call_p (exp
,
3699 structure_value_addr
,
3701 reg_parm_stack_space
,
3703 flags
, addr
, args_size
);
3705 /* Check if caller and callee disagree in promotion of function
3709 machine_mode caller_mode
, caller_promoted_mode
;
3710 machine_mode callee_mode
, callee_promoted_mode
;
3711 int caller_unsignedp
, callee_unsignedp
;
3712 tree caller_res
= DECL_RESULT (current_function_decl
);
3714 caller_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (caller_res
));
3715 caller_mode
= DECL_MODE (caller_res
);
3716 callee_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (funtype
));
3717 callee_mode
= TYPE_MODE (TREE_TYPE (funtype
));
3718 caller_promoted_mode
3719 = promote_function_mode (TREE_TYPE (caller_res
), caller_mode
,
3721 TREE_TYPE (current_function_decl
), 1);
3722 callee_promoted_mode
3723 = promote_function_mode (TREE_TYPE (funtype
), callee_mode
,
3726 if (caller_mode
!= VOIDmode
3727 && (caller_promoted_mode
!= callee_promoted_mode
3728 || ((caller_mode
!= caller_promoted_mode
3729 || callee_mode
!= callee_promoted_mode
)
3730 && (caller_unsignedp
!= callee_unsignedp
3731 || partial_subreg_p (caller_mode
, callee_mode
)))))
3734 maybe_complain_about_tail_call (exp
,
3735 "caller and callee disagree in"
3736 " promotion of function"
3741 /* Ensure current function's preferred stack boundary is at least
3742 what we need. Stack alignment may also increase preferred stack
3744 for (i
= 0; i
< num_actuals
; i
++)
3745 if (reg_parm_stack_space
> 0
3747 || args
[i
].partial
!= 0
3748 || args
[i
].pass_on_stack
)
3749 update_stack_alignment_for_call (&args
[i
].locate
);
3750 if (crtl
->preferred_stack_boundary
< preferred_stack_boundary
)
3751 crtl
->preferred_stack_boundary
= preferred_stack_boundary
;
3753 preferred_stack_boundary
= crtl
->preferred_stack_boundary
;
3755 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
3757 /* We want to make two insn chains; one for a sibling call, the other
3758 for a normal call. We will select one of the two chains after
3759 initial RTL generation is complete. */
3760 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
3762 int sibcall_failure
= 0;
3763 /* We want to emit any pending stack adjustments before the tail
3764 recursion "call". That way we know any adjustment after the tail
3765 recursion call can be ignored if we indeed use the tail
3767 saved_pending_stack_adjust save
;
3768 rtx_insn
*insns
, *before_call
, *after_args
;
3773 /* State variables we need to save and restore between
3775 save_pending_stack_adjust (&save
);
3778 flags
&= ~ECF_SIBCALL
;
3780 flags
|= ECF_SIBCALL
;
3782 /* Other state variables that we must reinitialize each time
3783 through the loop (that are not initialized by the loop itself). */
3787 /* Start a new sequence for the normal call case.
3789 From this point on, if the sibling call fails, we want to set
3790 sibcall_failure instead of continuing the loop. */
3793 /* Don't let pending stack adjusts add up to too much.
3794 Also, do all pending adjustments now if there is any chance
3795 this might be a call to alloca or if we are expanding a sibling
3797 Also do the adjustments before a throwing call, otherwise
3798 exception handling can fail; PR 19225. */
3799 if (maybe_ge (pending_stack_adjust
, 32)
3800 || (maybe_ne (pending_stack_adjust
, 0)
3801 && (flags
& ECF_MAY_BE_ALLOCA
))
3802 || (maybe_ne (pending_stack_adjust
, 0)
3803 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
3805 do_pending_stack_adjust ();
3807 /* Precompute any arguments as needed. */
3809 precompute_arguments (num_actuals
, args
);
3811 /* Now we are about to start emitting insns that can be deleted
3812 if a libcall is deleted. */
3813 if (pass
&& (flags
& ECF_MALLOC
))
3817 && crtl
->stack_protect_guard
3818 && targetm
.stack_protect_runtime_enabled_p ())
3819 stack_protect_epilogue ();
3821 adjusted_args_size
= args_size
;
3822 /* Compute the actual size of the argument block required. The variable
3823 and constant sizes must be combined, the size may have to be rounded,
3824 and there may be a minimum required size. When generating a sibcall
3825 pattern, do not round up, since we'll be re-using whatever space our
3827 unadjusted_args_size
3828 = compute_argument_block_size (reg_parm_stack_space
,
3829 &adjusted_args_size
,
3832 : preferred_stack_boundary
));
3834 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
3836 /* The argument block when performing a sibling call is the
3837 incoming argument block. */
3840 argblock
= crtl
->args
.internal_arg_pointer
;
3841 if (STACK_GROWS_DOWNWARD
)
3843 = plus_constant (Pmode
, argblock
, crtl
->args
.pretend_args_size
);
3846 = plus_constant (Pmode
, argblock
, -crtl
->args
.pretend_args_size
);
3848 HOST_WIDE_INT map_size
= constant_lower_bound (args_size
.constant
);
3849 stored_args_map
= sbitmap_alloc (map_size
);
3850 bitmap_clear (stored_args_map
);
3851 stored_args_watermark
= HOST_WIDE_INT_M1U
;
3854 /* If we have no actual push instructions, or shouldn't use them,
3855 make space for all args right now. */
3856 else if (adjusted_args_size
.var
!= 0)
3858 if (old_stack_level
== 0)
3860 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
3861 old_stack_pointer_delta
= stack_pointer_delta
;
3862 old_pending_adj
= pending_stack_adjust
;
3863 pending_stack_adjust
= 0;
3864 /* stack_arg_under_construction says whether a stack arg is
3865 being constructed at the old stack level. Pushing the stack
3866 gets a clean outgoing argument block. */
3867 old_stack_arg_under_construction
= stack_arg_under_construction
;
3868 stack_arg_under_construction
= 0;
3870 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
3871 if (flag_stack_usage_info
)
3872 current_function_has_unbounded_dynamic_stack_size
= 1;
3876 /* Note that we must go through the motions of allocating an argument
3877 block even if the size is zero because we may be storing args
3878 in the area reserved for register arguments, which may be part of
3881 poly_int64 needed
= adjusted_args_size
.constant
;
3883 /* Store the maximum argument space used. It will be pushed by
3884 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
3887 crtl
->outgoing_args_size
= upper_bound (crtl
->outgoing_args_size
,
3890 if (must_preallocate
)
3892 if (ACCUMULATE_OUTGOING_ARGS
)
3894 /* Since the stack pointer will never be pushed, it is
3895 possible for the evaluation of a parm to clobber
3896 something we have already written to the stack.
3897 Since most function calls on RISC machines do not use
3898 the stack, this is uncommon, but must work correctly.
3900 Therefore, we save any area of the stack that was already
3901 written and that we are using. Here we set up to do this
3902 by making a new stack usage map from the old one. The
3903 actual save will be done by store_one_arg.
3905 Another approach might be to try to reorder the argument
3906 evaluations to avoid this conflicting stack usage. */
3908 /* Since we will be writing into the entire argument area,
3909 the map must be allocated for its entire size, not just
3910 the part that is the responsibility of the caller. */
3911 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3912 needed
+= reg_parm_stack_space
;
3914 poly_int64 limit
= needed
;
3915 if (ARGS_GROW_DOWNWARD
)
3918 /* For polynomial sizes, this is the maximum possible
3919 size needed for arguments with a constant size
3921 HOST_WIDE_INT const_limit
= constant_lower_bound (limit
);
3922 highest_outgoing_arg_in_use
3923 = MAX (initial_highest_arg_in_use
, const_limit
);
3925 free (stack_usage_map_buf
);
3926 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
3927 stack_usage_map
= stack_usage_map_buf
;
3929 if (initial_highest_arg_in_use
)
3930 memcpy (stack_usage_map
, initial_stack_usage_map
,
3931 initial_highest_arg_in_use
);
3933 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3934 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3935 (highest_outgoing_arg_in_use
3936 - initial_highest_arg_in_use
));
3939 /* The address of the outgoing argument list must not be
3940 copied to a register here, because argblock would be left
3941 pointing to the wrong place after the call to
3942 allocate_dynamic_stack_space below. */
3944 argblock
= virtual_outgoing_args_rtx
;
3948 /* Try to reuse some or all of the pending_stack_adjust
3949 to get this space. */
3950 if (inhibit_defer_pop
== 0
3951 && (combine_pending_stack_adjustment_and_call
3953 unadjusted_args_size
,
3954 &adjusted_args_size
,
3955 preferred_unit_stack_boundary
)))
3957 /* combine_pending_stack_adjustment_and_call computes
3958 an adjustment before the arguments are allocated.
3959 Account for them and see whether or not the stack
3960 needs to go up or down. */
3961 needed
= unadjusted_args_size
- needed
;
3964 combine_pending_stack_adjustment_and_call. */
3965 gcc_checking_assert (ordered_p (needed
, 0));
3966 if (maybe_lt (needed
, 0))
3968 /* We're releasing stack space. */
3969 /* ??? We can avoid any adjustment at all if we're
3970 already aligned. FIXME. */
3971 pending_stack_adjust
= -needed
;
3972 do_pending_stack_adjust ();
3976 /* We need to allocate space. We'll do that in
3977 push_block below. */
3978 pending_stack_adjust
= 0;
3981 /* Special case this because overhead of `push_block' in
3982 this case is non-trivial. */
3983 if (known_eq (needed
, 0))
3984 argblock
= virtual_outgoing_args_rtx
;
3987 rtx needed_rtx
= gen_int_mode (needed
, Pmode
);
3988 argblock
= push_block (needed_rtx
, 0, 0);
3989 if (ARGS_GROW_DOWNWARD
)
3990 argblock
= plus_constant (Pmode
, argblock
, needed
);
3993 /* We only really need to call `copy_to_reg' in the case
3994 where push insns are going to be used to pass ARGBLOCK
3995 to a function call in ARGS. In that case, the stack
3996 pointer changes value from the allocation point to the
3997 call point, and hence the value of
3998 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3999 as well always do it. */
4000 argblock
= copy_to_reg (argblock
);
4005 if (ACCUMULATE_OUTGOING_ARGS
)
4007 /* The save/restore code in store_one_arg handles all
4008 cases except one: a constructor call (including a C
4009 function returning a BLKmode struct) to initialize
4011 if (stack_arg_under_construction
)
4015 (adjusted_args_size
.constant
4016 + (OUTGOING_REG_PARM_STACK_SPACE (!fndecl
? fntype
4017 : TREE_TYPE (fndecl
))
4018 ? 0 : reg_parm_stack_space
), Pmode
));
4019 if (old_stack_level
== 0)
4021 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
4022 old_stack_pointer_delta
= stack_pointer_delta
;
4023 old_pending_adj
= pending_stack_adjust
;
4024 pending_stack_adjust
= 0;
4025 /* stack_arg_under_construction says whether a stack
4026 arg is being constructed at the old stack level.
4027 Pushing the stack gets a clean outgoing argument
4029 old_stack_arg_under_construction
4030 = stack_arg_under_construction
;
4031 stack_arg_under_construction
= 0;
4032 /* Make a new map for the new argument list. */
4033 free (stack_usage_map_buf
);
4034 stack_usage_map_buf
= XCNEWVEC (char, highest_outgoing_arg_in_use
);
4035 stack_usage_map
= stack_usage_map_buf
;
4036 highest_outgoing_arg_in_use
= 0;
4037 stack_usage_watermark
= HOST_WIDE_INT_M1U
;
4039 /* We can pass TRUE as the 4th argument because we just
4040 saved the stack pointer and will restore it right after
4042 allocate_dynamic_stack_space (push_size
, 0, BIGGEST_ALIGNMENT
,
4046 /* If argument evaluation might modify the stack pointer,
4047 copy the address of the argument list to a register. */
4048 for (i
= 0; i
< num_actuals
; i
++)
4049 if (args
[i
].pass_on_stack
)
4051 argblock
= copy_addr_to_reg (argblock
);
4056 compute_argument_addresses (args
, argblock
, num_actuals
);
4058 /* Stack is properly aligned, pops can't safely be deferred during
4059 the evaluation of the arguments. */
4062 /* Precompute all register parameters. It isn't safe to compute
4063 anything once we have started filling any specific hard regs.
4064 TLS symbols sometimes need a call to resolve. Precompute
4065 register parameters before any stack pointer manipulation
4066 to avoid unaligned stack in the called function. */
4067 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
4071 /* Perform stack alignment before the first push (the last arg). */
4073 && maybe_gt (adjusted_args_size
.constant
, reg_parm_stack_space
)
4074 && maybe_ne (adjusted_args_size
.constant
, unadjusted_args_size
))
4076 /* When the stack adjustment is pending, we get better code
4077 by combining the adjustments. */
4078 if (maybe_ne (pending_stack_adjust
, 0)
4079 && ! inhibit_defer_pop
4080 && (combine_pending_stack_adjustment_and_call
4081 (&pending_stack_adjust
,
4082 unadjusted_args_size
,
4083 &adjusted_args_size
,
4084 preferred_unit_stack_boundary
)))
4085 do_pending_stack_adjust ();
4086 else if (argblock
== 0)
4087 anti_adjust_stack (gen_int_mode (adjusted_args_size
.constant
4088 - unadjusted_args_size
,
4091 /* Now that the stack is properly aligned, pops can't safely
4092 be deferred during the evaluation of the arguments. */
4095 /* Record the maximum pushed stack space size. We need to delay
4096 doing it this far to take into account the optimization done
4097 by combine_pending_stack_adjustment_and_call. */
4098 if (flag_stack_usage_info
4099 && !ACCUMULATE_OUTGOING_ARGS
4101 && adjusted_args_size
.var
== 0)
4103 poly_int64 pushed
= (adjusted_args_size
.constant
4104 + pending_stack_adjust
);
4105 current_function_pushed_stack_size
4106 = upper_bound (current_function_pushed_stack_size
, pushed
);
4109 funexp
= rtx_for_function_call (fndecl
, addr
);
4111 if (CALL_EXPR_STATIC_CHAIN (exp
))
4112 static_chain_value
= expand_normal (CALL_EXPR_STATIC_CHAIN (exp
));
4114 static_chain_value
= 0;
4116 #ifdef REG_PARM_STACK_SPACE
4117 /* Save the fixed argument area if it's part of the caller's frame and
4118 is clobbered by argument setup for this call. */
4119 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
4120 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
4121 &low_to_save
, &high_to_save
);
4124 /* Now store (and compute if necessary) all non-register parms.
4125 These come before register parms, since they can require block-moves,
4126 which could clobber the registers used for register parms.
4127 Parms which have partial registers are not stored here,
4128 but we do preallocate space here if they want that. */
4130 for (i
= 0; i
< num_actuals
; i
++)
4132 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
4134 rtx_insn
*before_arg
= get_last_insn ();
4136 /* We don't allow passing huge (> 2^30 B) arguments
4137 by value. It would cause an overflow later on. */
4138 if (constant_lower_bound (adjusted_args_size
.constant
)
4139 >= (1 << (HOST_BITS_PER_INT
- 2)))
4141 sorry ("passing too large argument on stack");
4145 if (store_one_arg (&args
[i
], argblock
, flags
,
4146 adjusted_args_size
.var
!= 0,
4147 reg_parm_stack_space
)
4149 && check_sibcall_argument_overlap (before_arg
,
4151 sibcall_failure
= 1;
4156 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
4157 gen_rtx_USE (VOIDmode
, args
[i
].stack
),
4161 /* If we have a parm that is passed in registers but not in memory
4162 and whose alignment does not permit a direct copy into registers,
4163 make a group of pseudos that correspond to each register that we
4165 if (STRICT_ALIGNMENT
)
4166 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
4168 /* Now store any partially-in-registers parm.
4169 This is the last place a block-move can happen. */
4171 for (i
= 0; i
< num_actuals
; i
++)
4172 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
4174 rtx_insn
*before_arg
= get_last_insn ();
4176 /* On targets with weird calling conventions (e.g. PA) it's
4177 hard to ensure that all cases of argument overlap between
4178 stack and registers work. Play it safe and bail out. */
4179 if (ARGS_GROW_DOWNWARD
&& !STACK_GROWS_DOWNWARD
)
4181 sibcall_failure
= 1;
4185 if (store_one_arg (&args
[i
], argblock
, flags
,
4186 adjusted_args_size
.var
!= 0,
4187 reg_parm_stack_space
)
4189 && check_sibcall_argument_overlap (before_arg
,
4191 sibcall_failure
= 1;
4194 bool any_regs
= false;
4195 for (i
= 0; i
< num_actuals
; i
++)
4196 if (args
[i
].reg
!= NULL_RTX
)
4199 targetm
.calls
.call_args (args
[i
].reg
, funtype
);
4202 targetm
.calls
.call_args (pc_rtx
, funtype
);
4204 /* Figure out the register where the value, if any, will come back. */
4206 if (TYPE_MODE (rettype
) != VOIDmode
4207 && ! structure_value_addr
)
4209 if (pcc_struct_value
)
4210 valreg
= hard_function_value (build_pointer_type (rettype
),
4211 fndecl
, NULL
, (pass
== 0));
4213 valreg
= hard_function_value (rettype
, fndecl
, fntype
,
4216 /* If VALREG is a PARALLEL whose first member has a zero
4217 offset, use that. This is for targets such as m68k that
4218 return the same value in multiple places. */
4219 if (GET_CODE (valreg
) == PARALLEL
)
4221 rtx elem
= XVECEXP (valreg
, 0, 0);
4222 rtx where
= XEXP (elem
, 0);
4223 rtx offset
= XEXP (elem
, 1);
4224 if (offset
== const0_rtx
4225 && GET_MODE (where
) == GET_MODE (valreg
))
4230 /* If register arguments require space on the stack and stack space
4231 was not preallocated, allocate stack space here for arguments
4232 passed in registers. */
4233 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
4234 && !ACCUMULATE_OUTGOING_ARGS
4235 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
4236 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
4238 /* Pass the function the address in which to return a
4240 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
4242 structure_value_addr
4243 = convert_memory_address (Pmode
, structure_value_addr
);
4244 emit_move_insn (struct_value
,
4246 force_operand (structure_value_addr
,
4249 if (REG_P (struct_value
))
4250 use_reg (&call_fusage
, struct_value
);
4253 after_args
= get_last_insn ();
4254 funexp
= prepare_call_address (fndecl
? fndecl
: fntype
, funexp
,
4255 static_chain_value
, &call_fusage
,
4256 reg_parm_seen
, flags
);
4258 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
4259 pass
== 0, &sibcall_failure
);
4261 /* Save a pointer to the last insn before the call, so that we can
4262 later safely search backwards to find the CALL_INSN. */
4263 before_call
= get_last_insn ();
4265 /* Set up next argument register. For sibling calls on machines
4266 with register windows this should be the incoming register. */
4268 next_arg_reg
= targetm
.calls
.function_incoming_arg
4269 (args_so_far
, function_arg_info::end_marker ());
4271 next_arg_reg
= targetm
.calls
.function_arg
4272 (args_so_far
, function_arg_info::end_marker ());
4274 if (pass
== 1 && (return_flags
& ERF_RETURNS_ARG
))
4276 int arg_nr
= return_flags
& ERF_RETURN_ARG_MASK
;
4277 arg_nr
= num_actuals
- arg_nr
- 1;
4279 && arg_nr
< num_actuals
4283 && GET_MODE (args
[arg_nr
].reg
) == GET_MODE (valreg
))
4285 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args
[arg_nr
].tree_value
)),
4286 gen_rtx_SET (valreg
, args
[arg_nr
].reg
),
4289 /* All arguments and registers used for the call must be set up by
4292 /* Stack must be properly aligned now. */
4294 || multiple_p (stack_pointer_delta
,
4295 preferred_unit_stack_boundary
));
4297 /* Generate the actual call instruction. */
4298 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
4299 adjusted_args_size
.constant
, struct_value_size
,
4300 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
4301 flags
, args_so_far
);
4305 rtx_call_insn
*last
;
4306 rtx datum
= NULL_RTX
;
4307 if (fndecl
!= NULL_TREE
)
4309 datum
= XEXP (DECL_RTL (fndecl
), 0);
4310 gcc_assert (datum
!= NULL_RTX
4311 && GET_CODE (datum
) == SYMBOL_REF
);
4313 last
= last_call_insn ();
4314 add_reg_note (last
, REG_CALL_DECL
, datum
);
4317 /* If the call setup or the call itself overlaps with anything
4318 of the argument setup we probably clobbered our call address.
4319 In that case we can't do sibcalls. */
4321 && check_sibcall_argument_overlap (after_args
, 0, 0))
4322 sibcall_failure
= 1;
4324 /* If a non-BLKmode value is returned at the most significant end
4325 of a register, shift the register right by the appropriate amount
4326 and update VALREG accordingly. BLKmode values are handled by the
4327 group load/store machinery below. */
4328 if (!structure_value_addr
4329 && !pcc_struct_value
4330 && TYPE_MODE (rettype
) != VOIDmode
4331 && TYPE_MODE (rettype
) != BLKmode
4333 && targetm
.calls
.return_in_msb (rettype
))
4335 if (shift_return_value (TYPE_MODE (rettype
), false, valreg
))
4336 sibcall_failure
= 1;
4337 valreg
= gen_rtx_REG (TYPE_MODE (rettype
), REGNO (valreg
));
4340 if (pass
&& (flags
& ECF_MALLOC
))
4342 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
4343 rtx_insn
*last
, *insns
;
4345 /* The return value from a malloc-like function is a pointer. */
4346 if (TREE_CODE (rettype
) == POINTER_TYPE
)
4347 mark_reg_pointer (temp
, MALLOC_ABI_ALIGNMENT
);
4349 emit_move_insn (temp
, valreg
);
4351 /* The return value from a malloc-like function cannot alias
4353 last
= get_last_insn ();
4354 add_reg_note (last
, REG_NOALIAS
, temp
);
4356 /* Write out the sequence. */
4357 insns
= get_insns ();
4363 /* For calls to `setjmp', etc., inform
4364 function.c:setjmp_warnings that it should complain if
4365 nonvolatile values are live. For functions that cannot
4366 return, inform flow that control does not fall through. */
4368 if ((flags
& ECF_NORETURN
) || pass
== 0)
4370 /* The barrier must be emitted
4371 immediately after the CALL_INSN. Some ports emit more
4372 than just a CALL_INSN above, so we must search for it here. */
4374 rtx_insn
*last
= get_last_insn ();
4375 while (!CALL_P (last
))
4377 last
= PREV_INSN (last
);
4378 /* There was no CALL_INSN? */
4379 gcc_assert (last
!= before_call
);
4382 emit_barrier_after (last
);
4384 /* Stack adjustments after a noreturn call are dead code.
4385 However when NO_DEFER_POP is in effect, we must preserve
4386 stack_pointer_delta. */
4387 if (inhibit_defer_pop
== 0)
4389 stack_pointer_delta
= old_stack_allocated
;
4390 pending_stack_adjust
= 0;
4394 /* If value type not void, return an rtx for the value. */
4396 if (TYPE_MODE (rettype
) == VOIDmode
4398 target
= const0_rtx
;
4399 else if (structure_value_addr
)
4401 if (target
== 0 || !MEM_P (target
))
4404 = gen_rtx_MEM (TYPE_MODE (rettype
),
4405 memory_address (TYPE_MODE (rettype
),
4406 structure_value_addr
));
4407 set_mem_attributes (target
, rettype
, 1);
4410 else if (pcc_struct_value
)
4412 /* This is the special C++ case where we need to
4413 know what the true target was. We take care to
4414 never use this value more than once in one expression. */
4415 target
= gen_rtx_MEM (TYPE_MODE (rettype
),
4416 copy_to_reg (valreg
));
4417 set_mem_attributes (target
, rettype
, 1);
4419 /* Handle calls that return values in multiple non-contiguous locations.
4420 The Irix 6 ABI has examples of this. */
4421 else if (GET_CODE (valreg
) == PARALLEL
)
4424 target
= emit_group_move_into_temps (valreg
);
4425 else if (rtx_equal_p (target
, valreg
))
4427 else if (GET_CODE (target
) == PARALLEL
)
4428 /* Handle the result of a emit_group_move_into_temps
4429 call in the previous pass. */
4430 emit_group_move (target
, valreg
);
4432 emit_group_store (target
, valreg
, rettype
,
4433 int_size_in_bytes (rettype
));
4436 && GET_MODE (target
) == TYPE_MODE (rettype
)
4437 && GET_MODE (target
) == GET_MODE (valreg
))
4439 bool may_overlap
= false;
4441 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
4442 reg to a plain register. */
4443 if (!REG_P (target
) || HARD_REGISTER_P (target
))
4444 valreg
= avoid_likely_spilled_reg (valreg
);
4446 /* If TARGET is a MEM in the argument area, and we have
4447 saved part of the argument area, then we can't store
4448 directly into TARGET as it may get overwritten when we
4449 restore the argument save area below. Don't work too
4450 hard though and simply force TARGET to a register if it
4451 is a MEM; the optimizer is quite likely to sort it out. */
4452 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
4453 for (i
= 0; i
< num_actuals
; i
++)
4454 if (args
[i
].save_area
)
4461 target
= copy_to_reg (valreg
);
4464 /* TARGET and VALREG cannot be equal at this point
4465 because the latter would not have
4466 REG_FUNCTION_VALUE_P true, while the former would if
4467 it were referring to the same register.
4469 If they refer to the same register, this move will be
4470 a no-op, except when function inlining is being
4472 emit_move_insn (target
, valreg
);
4474 /* If we are setting a MEM, this code must be executed.
4475 Since it is emitted after the call insn, sibcall
4476 optimization cannot be performed in that case. */
4478 sibcall_failure
= 1;
4482 target
= copy_to_reg (avoid_likely_spilled_reg (valreg
));
4484 /* If we promoted this return value, make the proper SUBREG.
4485 TARGET might be const0_rtx here, so be careful. */
4487 && TYPE_MODE (rettype
) != BLKmode
4488 && GET_MODE (target
) != TYPE_MODE (rettype
))
4490 tree type
= rettype
;
4491 int unsignedp
= TYPE_UNSIGNED (type
);
4494 /* Ensure we promote as expected, and get the new unsignedness. */
4495 pmode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
4497 gcc_assert (GET_MODE (target
) == pmode
);
4499 poly_uint64 offset
= subreg_lowpart_offset (TYPE_MODE (type
),
4501 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
4502 SUBREG_PROMOTED_VAR_P (target
) = 1;
4503 SUBREG_PROMOTED_SET (target
, unsignedp
);
4506 /* If size of args is variable or this was a constructor call for a stack
4507 argument, restore saved stack-pointer value. */
4509 if (old_stack_level
)
4511 rtx_insn
*prev
= get_last_insn ();
4513 emit_stack_restore (SAVE_BLOCK
, old_stack_level
);
4514 stack_pointer_delta
= old_stack_pointer_delta
;
4516 fixup_args_size_notes (prev
, get_last_insn (), stack_pointer_delta
);
4518 pending_stack_adjust
= old_pending_adj
;
4519 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
4520 stack_arg_under_construction
= old_stack_arg_under_construction
;
4521 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4522 stack_usage_map
= initial_stack_usage_map
;
4523 stack_usage_watermark
= initial_stack_usage_watermark
;
4524 sibcall_failure
= 1;
4526 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
4528 #ifdef REG_PARM_STACK_SPACE
4530 restore_fixed_argument_area (save_area
, argblock
,
4531 high_to_save
, low_to_save
);
4534 /* If we saved any argument areas, restore them. */
4535 for (i
= 0; i
< num_actuals
; i
++)
4536 if (args
[i
].save_area
)
4538 machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
4540 = gen_rtx_MEM (save_mode
,
4541 memory_address (save_mode
,
4542 XEXP (args
[i
].stack_slot
, 0)));
4544 if (save_mode
!= BLKmode
)
4545 emit_move_insn (stack_area
, args
[i
].save_area
);
4547 emit_block_move (stack_area
, args
[i
].save_area
,
4549 (args
[i
].locate
.size
.constant
, Pmode
)),
4550 BLOCK_OP_CALL_PARM
);
4553 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4554 stack_usage_map
= initial_stack_usage_map
;
4555 stack_usage_watermark
= initial_stack_usage_watermark
;
4558 /* If this was alloca, record the new stack level. */
4559 if (flags
& ECF_MAY_BE_ALLOCA
)
4560 record_new_stack_level ();
4562 /* Free up storage we no longer need. */
4563 for (i
= 0; i
< num_actuals
; ++i
)
4564 free (args
[i
].aligned_regs
);
4566 targetm
.calls
.end_call_args ();
4568 insns
= get_insns ();
4573 tail_call_insns
= insns
;
4575 /* Restore the pending stack adjustment now that we have
4576 finished generating the sibling call sequence. */
4578 restore_pending_stack_adjust (&save
);
4580 /* Prepare arg structure for next iteration. */
4581 for (i
= 0; i
< num_actuals
; i
++)
4584 args
[i
].aligned_regs
= 0;
4588 sbitmap_free (stored_args_map
);
4589 internal_arg_pointer_exp_state
.scan_start
= NULL
;
4590 internal_arg_pointer_exp_state
.cache
.release ();
4594 normal_call_insns
= insns
;
4596 /* Verify that we've deallocated all the stack we used. */
4597 gcc_assert ((flags
& ECF_NORETURN
)
4598 || known_eq (old_stack_allocated
,
4600 - pending_stack_adjust
));
4603 /* If something prevents making this a sibling call,
4604 zero out the sequence. */
4605 if (sibcall_failure
)
4606 tail_call_insns
= NULL
;
4611 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
4612 arguments too, as argument area is now clobbered by the call. */
4613 if (tail_call_insns
)
4615 emit_insn (tail_call_insns
);
4616 crtl
->tail_call_emit
= true;
4620 emit_insn (normal_call_insns
);
4622 /* Ideally we'd emit a message for all of the ways that it could
4624 maybe_complain_about_tail_call (exp
, "tail call production failed");
4627 currently_expanding_call
--;
4629 free (stack_usage_map_buf
);
4634 /* A sibling call sequence invalidates any REG_EQUIV notes made for
4635 this function's incoming arguments.
4637 At the start of RTL generation we know the only REG_EQUIV notes
4638 in the rtl chain are those for incoming arguments, so we can look
4639 for REG_EQUIV notes between the start of the function and the
4640 NOTE_INSN_FUNCTION_BEG.
4642 This is (slight) overkill. We could keep track of the highest
4643 argument we clobber and be more selective in removing notes, but it
4644 does not seem to be worth the effort. */
4647 fixup_tail_calls (void)
4651 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4655 /* There are never REG_EQUIV notes for the incoming arguments
4656 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
4658 && NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
)
4661 note
= find_reg_note (insn
, REG_EQUIV
, 0);
4663 remove_note (insn
, note
);
4664 note
= find_reg_note (insn
, REG_EQUIV
, 0);
4669 /* Traverse a list of TYPES and expand all complex types into their
4672 split_complex_types (tree types
)
4676 /* Before allocating memory, check for the common case of no complex. */
4677 for (p
= types
; p
; p
= TREE_CHAIN (p
))
4679 tree type
= TREE_VALUE (p
);
4680 if (TREE_CODE (type
) == COMPLEX_TYPE
4681 && targetm
.calls
.split_complex_arg (type
))
4687 types
= copy_list (types
);
4689 for (p
= types
; p
; p
= TREE_CHAIN (p
))
4691 tree complex_type
= TREE_VALUE (p
);
4693 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
4694 && targetm
.calls
.split_complex_arg (complex_type
))
4698 /* Rewrite complex type with component type. */
4699 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
4700 next
= TREE_CHAIN (p
);
4702 /* Add another component type for the imaginary part. */
4703 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
4704 TREE_CHAIN (p
) = imag
;
4705 TREE_CHAIN (imag
) = next
;
4707 /* Skip the newly created node. */
4715 /* Output a library call to function ORGFUN (a SYMBOL_REF rtx)
4716 for a value of mode OUTMODE,
4717 with NARGS different arguments, passed as ARGS.
4718 Store the return value if RETVAL is nonzero: store it in VALUE if
4719 VALUE is nonnull, otherwise pick a convenient location. In either
4720 case return the location of the stored value.
4722 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4723 `const' calls, LCT_PURE for `pure' calls, or another LCT_ value for
4724 other types of library calls. */
4727 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
4728 enum libcall_type fn_type
,
4729 machine_mode outmode
, int nargs
, rtx_mode_t
*args
)
4731 /* Total size in bytes of all the stack-parms scanned so far. */
4732 struct args_size args_size
;
4733 /* Size of arguments before any adjustments (such as rounding). */
4734 struct args_size original_args_size
;
4737 /* Todo, choose the correct decl type of orgfun. Sadly this information
4738 isn't present here, so we default to native calling abi here. */
4739 tree fndecl ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
4740 tree fntype ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
4743 CUMULATIVE_ARGS args_so_far_v
;
4744 cumulative_args_t args_so_far
;
4751 struct locate_and_pad_arg_data locate
;
4755 int old_inhibit_defer_pop
= inhibit_defer_pop
;
4756 rtx call_fusage
= 0;
4759 int pcc_struct_value
= 0;
4760 poly_int64 struct_value_size
= 0;
4762 int reg_parm_stack_space
= 0;
4764 rtx_insn
*before_call
;
4765 bool have_push_fusage
;
4766 tree tfom
; /* type_for_mode (outmode, 0) */
4768 #ifdef REG_PARM_STACK_SPACE
4769 /* Define the boundary of the register parm stack space that needs to be
4771 int low_to_save
= 0, high_to_save
= 0;
4772 rtx save_area
= 0; /* Place that it is saved. */
4775 /* Size of the stack reserved for parameter registers. */
4776 unsigned int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
4777 char *initial_stack_usage_map
= stack_usage_map
;
4778 unsigned HOST_WIDE_INT initial_stack_usage_watermark
= stack_usage_watermark
;
4779 char *stack_usage_map_buf
= NULL
;
4781 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
4783 #ifdef REG_PARM_STACK_SPACE
4784 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
4787 /* By default, library functions cannot throw. */
4788 flags
= ECF_NOTHROW
;
4801 flags
|= ECF_NORETURN
;
4804 flags
&= ~ECF_NOTHROW
;
4806 case LCT_RETURNS_TWICE
:
4807 flags
= ECF_RETURNS_TWICE
;
4812 /* Ensure current function's preferred stack boundary is at least
4814 if (crtl
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
4815 crtl
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
4817 /* If this kind of value comes back in memory,
4818 decide where in memory it should come back. */
4819 if (outmode
!= VOIDmode
)
4821 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
4822 if (aggregate_value_p (tfom
, 0))
4824 #ifdef PCC_STATIC_STRUCT_RETURN
4826 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
4827 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
4828 pcc_struct_value
= 1;
4830 value
= gen_reg_rtx (outmode
);
4831 #else /* not PCC_STATIC_STRUCT_RETURN */
4832 struct_value_size
= GET_MODE_SIZE (outmode
);
4833 if (value
!= 0 && MEM_P (value
))
4836 mem_value
= assign_temp (tfom
, 1, 1);
4838 /* This call returns a big structure. */
4839 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
4843 tfom
= void_type_node
;
4845 /* ??? Unfinished: must pass the memory address as an argument. */
4847 /* Copy all the libcall-arguments out of the varargs data
4848 and into a vector ARGVEC.
4850 Compute how to pass each argument. We only support a very small subset
4851 of the full argument passing conventions to limit complexity here since
4852 library functions shouldn't have many args. */
4854 argvec
= XALLOCAVEC (struct arg
, nargs
+ 1);
4855 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
4857 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
4858 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v
, outmode
, fun
);
4860 INIT_CUMULATIVE_ARGS (args_so_far_v
, NULL_TREE
, fun
, 0, nargs
);
4862 args_so_far
= pack_cumulative_args (&args_so_far_v
);
4864 args_size
.constant
= 0;
4871 /* If there's a structure value address to be passed,
4872 either pass it in the special place, or pass it as an extra argument. */
4873 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
4875 rtx addr
= XEXP (mem_value
, 0);
4879 /* Make sure it is a reasonable operand for a move or push insn. */
4880 if (!REG_P (addr
) && !MEM_P (addr
)
4881 && !(CONSTANT_P (addr
)
4882 && targetm
.legitimate_constant_p (Pmode
, addr
)))
4883 addr
= force_operand (addr
, NULL_RTX
);
4885 argvec
[count
].value
= addr
;
4886 argvec
[count
].mode
= Pmode
;
4887 argvec
[count
].partial
= 0;
4889 function_arg_info
ptr_arg (Pmode
, /*named=*/true);
4890 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
, ptr_arg
);
4891 gcc_assert (targetm
.calls
.arg_partial_bytes (args_so_far
, ptr_arg
) == 0);
4893 locate_and_pad_parm (Pmode
, NULL_TREE
,
4894 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4897 argvec
[count
].reg
!= 0,
4899 reg_parm_stack_space
, 0,
4900 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
4902 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
4903 || reg_parm_stack_space
> 0)
4904 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
4906 targetm
.calls
.function_arg_advance (args_so_far
, ptr_arg
);
4911 for (unsigned int i
= 0; count
< nargs
; i
++, count
++)
4913 rtx val
= args
[i
].first
;
4914 function_arg_info
arg (args
[i
].second
, /*named=*/true);
4917 /* We cannot convert the arg value to the mode the library wants here;
4918 must do it earlier where we know the signedness of the arg. */
4919 gcc_assert (arg
.mode
!= BLKmode
4920 && (GET_MODE (val
) == arg
.mode
4921 || GET_MODE (val
) == VOIDmode
));
4923 /* Make sure it is a reasonable operand for a move or push insn. */
4924 if (!REG_P (val
) && !MEM_P (val
)
4925 && !(CONSTANT_P (val
)
4926 && targetm
.legitimate_constant_p (arg
.mode
, val
)))
4927 val
= force_operand (val
, NULL_RTX
);
4929 if (pass_by_reference (&args_so_far_v
, arg
))
4932 int must_copy
= !reference_callee_copied (&args_so_far_v
, arg
);
4934 /* If this was a CONST function, it is now PURE since it now
4936 if (flags
& ECF_CONST
)
4938 flags
&= ~ECF_CONST
;
4942 if (MEM_P (val
) && !must_copy
)
4944 tree val_expr
= MEM_EXPR (val
);
4946 mark_addressable (val_expr
);
4951 slot
= assign_temp (lang_hooks
.types
.type_for_mode (arg
.mode
, 0),
4953 emit_move_insn (slot
, val
);
4956 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
4957 gen_rtx_USE (VOIDmode
, slot
),
4960 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
4961 gen_rtx_CLOBBER (VOIDmode
,
4966 arg
.pass_by_reference
= true;
4967 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
4970 arg
.mode
= promote_function_mode (NULL_TREE
, arg
.mode
, &unsigned_p
,
4972 argvec
[count
].mode
= arg
.mode
;
4973 argvec
[count
].value
= convert_modes (arg
.mode
, GET_MODE (val
), val
,
4975 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
, arg
);
4977 argvec
[count
].partial
4978 = targetm
.calls
.arg_partial_bytes (args_so_far
, arg
);
4980 if (argvec
[count
].reg
== 0
4981 || argvec
[count
].partial
!= 0
4982 || reg_parm_stack_space
> 0)
4984 locate_and_pad_parm (arg
.mode
, NULL_TREE
,
4985 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4988 argvec
[count
].reg
!= 0,
4990 reg_parm_stack_space
, argvec
[count
].partial
,
4991 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
4992 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
4993 gcc_assert (!argvec
[count
].locate
.size
.var
);
4995 #ifdef BLOCK_REG_PADDING
4997 /* The argument is passed entirely in registers. See at which
4998 end it should be padded. */
4999 argvec
[count
].locate
.where_pad
=
5000 BLOCK_REG_PADDING (arg
.mode
, NULL_TREE
,
5001 known_le (GET_MODE_SIZE (arg
.mode
),
5005 targetm
.calls
.function_arg_advance (args_so_far
, arg
);
5008 for (int i
= 0; i
< nargs
; i
++)
5009 if (reg_parm_stack_space
> 0
5010 || argvec
[i
].reg
== 0
5011 || argvec
[i
].partial
!= 0)
5012 update_stack_alignment_for_call (&argvec
[i
].locate
);
5014 /* If this machine requires an external definition for library
5015 functions, write one out. */
5016 assemble_external_libcall (fun
);
5018 original_args_size
= args_size
;
5019 args_size
.constant
= (aligned_upper_bound (args_size
.constant
5020 + stack_pointer_delta
,
5022 - stack_pointer_delta
);
5024 args_size
.constant
= upper_bound (args_size
.constant
,
5025 reg_parm_stack_space
);
5027 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
5028 args_size
.constant
-= reg_parm_stack_space
;
5030 crtl
->outgoing_args_size
= upper_bound (crtl
->outgoing_args_size
,
5031 args_size
.constant
);
5033 if (flag_stack_usage_info
&& !ACCUMULATE_OUTGOING_ARGS
)
5035 poly_int64 pushed
= args_size
.constant
+ pending_stack_adjust
;
5036 current_function_pushed_stack_size
5037 = upper_bound (current_function_pushed_stack_size
, pushed
);
5040 if (ACCUMULATE_OUTGOING_ARGS
)
5042 /* Since the stack pointer will never be pushed, it is possible for
5043 the evaluation of a parm to clobber something we have already
5044 written to the stack. Since most function calls on RISC machines
5045 do not use the stack, this is uncommon, but must work correctly.
5047 Therefore, we save any area of the stack that was already written
5048 and that we are using. Here we set up to do this by making a new
5049 stack usage map from the old one.
5051 Another approach might be to try to reorder the argument
5052 evaluations to avoid this conflicting stack usage. */
5054 needed
= args_size
.constant
;
5056 /* Since we will be writing into the entire argument area, the
5057 map must be allocated for its entire size, not just the part that
5058 is the responsibility of the caller. */
5059 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
5060 needed
+= reg_parm_stack_space
;
5062 poly_int64 limit
= needed
;
5063 if (ARGS_GROW_DOWNWARD
)
5066 /* For polynomial sizes, this is the maximum possible size needed
5067 for arguments with a constant size and offset. */
5068 HOST_WIDE_INT const_limit
= constant_lower_bound (limit
);
5069 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
5072 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
5073 stack_usage_map
= stack_usage_map_buf
;
5075 if (initial_highest_arg_in_use
)
5076 memcpy (stack_usage_map
, initial_stack_usage_map
,
5077 initial_highest_arg_in_use
);
5079 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
5080 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
5081 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
5084 /* We must be careful to use virtual regs before they're instantiated,
5085 and real regs afterwards. Loop optimization, for example, can create
5086 new libcalls after we've instantiated the virtual regs, and if we
5087 use virtuals anyway, they won't match the rtl patterns. */
5089 if (virtuals_instantiated
)
5090 argblock
= plus_constant (Pmode
, stack_pointer_rtx
,
5091 STACK_POINTER_OFFSET
);
5093 argblock
= virtual_outgoing_args_rtx
;
5098 argblock
= push_block (gen_int_mode (args_size
.constant
, Pmode
), 0, 0);
5101 /* We push args individually in reverse order, perform stack alignment
5102 before the first push (the last arg). */
5104 anti_adjust_stack (gen_int_mode (args_size
.constant
5105 - original_args_size
.constant
,
5110 #ifdef REG_PARM_STACK_SPACE
5111 if (ACCUMULATE_OUTGOING_ARGS
)
5113 /* The argument list is the property of the called routine and it
5114 may clobber it. If the fixed area has been used for previous
5115 parameters, we must save and restore it. */
5116 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
5117 &low_to_save
, &high_to_save
);
5121 /* When expanding a normal call, args are stored in push order,
5122 which is the reverse of what we have here. */
5123 bool any_regs
= false;
5124 for (int i
= nargs
; i
-- > 0; )
5125 if (argvec
[i
].reg
!= NULL_RTX
)
5127 targetm
.calls
.call_args (argvec
[i
].reg
, NULL_TREE
);
5131 targetm
.calls
.call_args (pc_rtx
, NULL_TREE
);
5133 /* Push the args that need to be pushed. */
5135 have_push_fusage
= false;
5137 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5138 are to be pushed. */
5139 for (count
= 0; count
< nargs
; count
++, argnum
--)
5141 machine_mode mode
= argvec
[argnum
].mode
;
5142 rtx val
= argvec
[argnum
].value
;
5143 rtx reg
= argvec
[argnum
].reg
;
5144 int partial
= argvec
[argnum
].partial
;
5145 unsigned int parm_align
= argvec
[argnum
].locate
.boundary
;
5146 poly_int64 lower_bound
= 0, upper_bound
= 0;
5148 if (! (reg
!= 0 && partial
== 0))
5152 if (ACCUMULATE_OUTGOING_ARGS
)
5154 /* If this is being stored into a pre-allocated, fixed-size,
5155 stack area, save any previous data at that location. */
5157 if (ARGS_GROW_DOWNWARD
)
5159 /* stack_slot is negative, but we want to index stack_usage_map
5160 with positive values. */
5161 upper_bound
= -argvec
[argnum
].locate
.slot_offset
.constant
+ 1;
5162 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
5166 lower_bound
= argvec
[argnum
].locate
.slot_offset
.constant
;
5167 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
5170 if (stack_region_maybe_used_p (lower_bound
, upper_bound
,
5171 reg_parm_stack_space
))
5173 /* We need to make a save area. */
5175 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
5176 machine_mode save_mode
5177 = int_mode_for_size (size
, 1).else_blk ();
5179 = plus_constant (Pmode
, argblock
,
5180 argvec
[argnum
].locate
.offset
.constant
);
5182 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
5184 if (save_mode
== BLKmode
)
5186 argvec
[argnum
].save_area
5187 = assign_stack_temp (BLKmode
,
5188 argvec
[argnum
].locate
.size
.constant
5191 emit_block_move (validize_mem
5192 (copy_rtx (argvec
[argnum
].save_area
)),
5195 (argvec
[argnum
].locate
.size
.constant
,
5197 BLOCK_OP_CALL_PARM
);
5201 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
5203 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
5208 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, parm_align
,
5209 partial
, reg
, 0, argblock
,
5211 (argvec
[argnum
].locate
.offset
.constant
, Pmode
)),
5212 reg_parm_stack_space
,
5213 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
), false);
5215 /* Now mark the segment we just used. */
5216 if (ACCUMULATE_OUTGOING_ARGS
)
5217 mark_stack_region_used (lower_bound
, upper_bound
);
5221 /* Indicate argument access so that alias.c knows that these
5224 use
= plus_constant (Pmode
, argblock
,
5225 argvec
[argnum
].locate
.offset
.constant
);
5226 else if (have_push_fusage
)
5230 /* When arguments are pushed, trying to tell alias.c where
5231 exactly this argument is won't work, because the
5232 auto-increment causes confusion. So we merely indicate
5233 that we access something with a known mode somewhere on
5235 use
= gen_rtx_PLUS (Pmode
, stack_pointer_rtx
,
5236 gen_rtx_SCRATCH (Pmode
));
5237 have_push_fusage
= true;
5239 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
5240 use
= gen_rtx_USE (VOIDmode
, use
);
5241 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
5247 fun
= prepare_call_address (NULL
, fun
, NULL
, &call_fusage
, 0, 0);
5249 /* Now load any reg parms into their regs. */
5251 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5252 are to be pushed. */
5253 for (count
= 0; count
< nargs
; count
++, argnum
--)
5255 machine_mode mode
= argvec
[argnum
].mode
;
5256 rtx val
= argvec
[argnum
].value
;
5257 rtx reg
= argvec
[argnum
].reg
;
5258 int partial
= argvec
[argnum
].partial
;
5260 /* Handle calls that pass values in multiple non-contiguous
5261 locations. The PA64 has examples of this for library calls. */
5262 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
5263 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
5264 else if (reg
!= 0 && partial
== 0)
5266 emit_move_insn (reg
, val
);
5267 #ifdef BLOCK_REG_PADDING
5268 poly_int64 size
= GET_MODE_SIZE (argvec
[argnum
].mode
);
5270 /* Copied from load_register_parameters. */
5272 /* Handle case where we have a value that needs shifting
5273 up to the msb. eg. a QImode value and we're padding
5274 upward on a BYTES_BIG_ENDIAN machine. */
5275 if (known_lt (size
, UNITS_PER_WORD
)
5276 && (argvec
[argnum
].locate
.where_pad
5277 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
5280 poly_int64 shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
5282 /* Assigning REG here rather than a temp makes CALL_FUSAGE
5283 report the whole reg as used. Strictly speaking, the
5284 call only uses SIZE bytes at the msb end, but it doesn't
5285 seem worth generating rtl to say that. */
5286 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
5287 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
, shift
, reg
, 1);
5289 emit_move_insn (reg
, x
);
5297 /* Any regs containing parms remain in use through the call. */
5298 for (count
= 0; count
< nargs
; count
++)
5300 rtx reg
= argvec
[count
].reg
;
5301 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
5302 use_group_regs (&call_fusage
, reg
);
5305 int partial
= argvec
[count
].partial
;
5309 gcc_assert (partial
% UNITS_PER_WORD
== 0);
5310 nregs
= partial
/ UNITS_PER_WORD
;
5311 use_regs (&call_fusage
, REGNO (reg
), nregs
);
5314 use_reg (&call_fusage
, reg
);
5318 /* Pass the function the address in which to return a structure value. */
5319 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
5321 emit_move_insn (struct_value
,
5323 force_operand (XEXP (mem_value
, 0),
5325 if (REG_P (struct_value
))
5326 use_reg (&call_fusage
, struct_value
);
5329 /* Don't allow popping to be deferred, since then
5330 cse'ing of library calls could delete a call and leave the pop. */
5332 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
5333 ? hard_libcall_value (outmode
, orgfun
) : NULL_RTX
);
5335 /* Stack must be properly aligned now. */
5336 gcc_assert (multiple_p (stack_pointer_delta
,
5337 PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
));
5339 before_call
= get_last_insn ();
5341 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
5342 will set inhibit_defer_pop to that value. */
5343 /* The return type is needed to decide how many bytes the function pops.
5344 Signedness plays no role in that, so for simplicity, we pretend it's
5345 always signed. We also assume that the list of arguments passed has
5346 no impact, so we pretend it is unknown. */
5348 emit_call_1 (fun
, NULL
,
5349 get_identifier (XSTR (orgfun
, 0)),
5350 build_function_type (tfom
, NULL_TREE
),
5351 original_args_size
.constant
, args_size
.constant
,
5353 targetm
.calls
.function_arg (args_so_far
,
5354 function_arg_info::end_marker ()),
5356 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, args_so_far
);
5361 gcc_assert (GET_CODE (datum
) == SYMBOL_REF
);
5362 rtx_call_insn
*last
= last_call_insn ();
5363 add_reg_note (last
, REG_CALL_DECL
, datum
);
5366 /* Right-shift returned value if necessary. */
5367 if (!pcc_struct_value
5368 && TYPE_MODE (tfom
) != BLKmode
5369 && targetm
.calls
.return_in_msb (tfom
))
5371 shift_return_value (TYPE_MODE (tfom
), false, valreg
);
5372 valreg
= gen_rtx_REG (TYPE_MODE (tfom
), REGNO (valreg
));
5375 targetm
.calls
.end_call_args ();
5377 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
5378 that it should complain if nonvolatile values are live. For
5379 functions that cannot return, inform flow that control does not
5381 if (flags
& ECF_NORETURN
)
5383 /* The barrier note must be emitted
5384 immediately after the CALL_INSN. Some ports emit more than
5385 just a CALL_INSN above, so we must search for it here. */
5386 rtx_insn
*last
= get_last_insn ();
5387 while (!CALL_P (last
))
5389 last
= PREV_INSN (last
);
5390 /* There was no CALL_INSN? */
5391 gcc_assert (last
!= before_call
);
5394 emit_barrier_after (last
);
5397 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
5398 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
5399 if (flags
& ECF_NOTHROW
)
5401 rtx_insn
*last
= get_last_insn ();
5402 while (!CALL_P (last
))
5404 last
= PREV_INSN (last
);
5405 /* There was no CALL_INSN? */
5406 gcc_assert (last
!= before_call
);
5409 make_reg_eh_region_note_nothrow_nononlocal (last
);
5412 /* Now restore inhibit_defer_pop to its actual original value. */
5417 /* Copy the value to the right place. */
5418 if (outmode
!= VOIDmode
&& retval
)
5424 if (value
!= mem_value
)
5425 emit_move_insn (value
, mem_value
);
5427 else if (GET_CODE (valreg
) == PARALLEL
)
5430 value
= gen_reg_rtx (outmode
);
5431 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
5435 /* Convert to the proper mode if a promotion has been active. */
5436 if (GET_MODE (valreg
) != outmode
)
5438 int unsignedp
= TYPE_UNSIGNED (tfom
);
5440 gcc_assert (promote_function_mode (tfom
, outmode
, &unsignedp
,
5441 fndecl
? TREE_TYPE (fndecl
) : fntype
, 1)
5442 == GET_MODE (valreg
));
5443 valreg
= convert_modes (outmode
, GET_MODE (valreg
), valreg
, 0);
5447 emit_move_insn (value
, valreg
);
5453 if (ACCUMULATE_OUTGOING_ARGS
)
5455 #ifdef REG_PARM_STACK_SPACE
5457 restore_fixed_argument_area (save_area
, argblock
,
5458 high_to_save
, low_to_save
);
5461 /* If we saved any argument areas, restore them. */
5462 for (count
= 0; count
< nargs
; count
++)
5463 if (argvec
[count
].save_area
)
5465 machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
5466 rtx adr
= plus_constant (Pmode
, argblock
,
5467 argvec
[count
].locate
.offset
.constant
);
5468 rtx stack_area
= gen_rtx_MEM (save_mode
,
5469 memory_address (save_mode
, adr
));
5471 if (save_mode
== BLKmode
)
5472 emit_block_move (stack_area
,
5474 (copy_rtx (argvec
[count
].save_area
)),
5476 (argvec
[count
].locate
.size
.constant
, Pmode
)),
5477 BLOCK_OP_CALL_PARM
);
5479 emit_move_insn (stack_area
, argvec
[count
].save_area
);
5482 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
5483 stack_usage_map
= initial_stack_usage_map
;
5484 stack_usage_watermark
= initial_stack_usage_watermark
;
5487 free (stack_usage_map_buf
);
5494 /* Store a single argument for a function call
5495 into the register or memory area where it must be passed.
5496 *ARG describes the argument value and where to pass it.
5498 ARGBLOCK is the address of the stack-block for all the arguments,
5499 or 0 on a machine where arguments are pushed individually.
5501 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
5502 so must be careful about how the stack is used.
5504 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
5505 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
5506 that we need not worry about saving and restoring the stack.
5508 FNDECL is the declaration of the function we are calling.
5510 Return nonzero if this arg should cause sibcall failure,
5514 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
5515 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
5517 tree pval
= arg
->tree_value
;
5520 poly_int64 used
= 0;
5521 poly_int64 lower_bound
= 0, upper_bound
= 0;
5522 int sibcall_failure
= 0;
5524 if (TREE_CODE (pval
) == ERROR_MARK
)
5527 /* Push a new temporary level for any temporaries we make for
5531 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
5533 /* If this is being stored into a pre-allocated, fixed-size, stack area,
5534 save any previous data at that location. */
5535 if (argblock
&& ! variable_size
&& arg
->stack
)
5537 if (ARGS_GROW_DOWNWARD
)
5539 /* stack_slot is negative, but we want to index stack_usage_map
5540 with positive values. */
5541 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
5543 rtx offset
= XEXP (XEXP (arg
->stack_slot
, 0), 1);
5544 upper_bound
= -rtx_to_poly_int64 (offset
) + 1;
5549 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
5553 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
5555 rtx offset
= XEXP (XEXP (arg
->stack_slot
, 0), 1);
5556 lower_bound
= rtx_to_poly_int64 (offset
);
5561 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
5564 if (stack_region_maybe_used_p (lower_bound
, upper_bound
,
5565 reg_parm_stack_space
))
5567 /* We need to make a save area. */
5568 poly_uint64 size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
5569 machine_mode save_mode
5570 = int_mode_for_size (size
, 1).else_blk ();
5571 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
5572 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
5574 if (save_mode
== BLKmode
)
5577 = assign_temp (TREE_TYPE (arg
->tree_value
), 1, 1);
5578 preserve_temp_slots (arg
->save_area
);
5579 emit_block_move (validize_mem (copy_rtx (arg
->save_area
)),
5582 (arg
->locate
.size
.constant
, Pmode
)),
5583 BLOCK_OP_CALL_PARM
);
5587 arg
->save_area
= gen_reg_rtx (save_mode
);
5588 emit_move_insn (arg
->save_area
, stack_area
);
5594 /* If this isn't going to be placed on both the stack and in registers,
5595 set up the register and number of words. */
5596 if (! arg
->pass_on_stack
)
5598 if (flags
& ECF_SIBCALL
)
5599 reg
= arg
->tail_call_reg
;
5602 partial
= arg
->partial
;
5605 /* Being passed entirely in a register. We shouldn't be called in
5607 gcc_assert (reg
== 0 || partial
!= 0);
5609 /* If this arg needs special alignment, don't load the registers
5611 if (arg
->n_aligned_regs
!= 0)
5614 /* If this is being passed partially in a register, we can't evaluate
5615 it directly into its stack slot. Otherwise, we can. */
5616 if (arg
->value
== 0)
5618 /* stack_arg_under_construction is nonzero if a function argument is
5619 being evaluated directly into the outgoing argument list and
5620 expand_call must take special action to preserve the argument list
5621 if it is called recursively.
5623 For scalar function arguments stack_usage_map is sufficient to
5624 determine which stack slots must be saved and restored. Scalar
5625 arguments in general have pass_on_stack == 0.
5627 If this argument is initialized by a function which takes the
5628 address of the argument (a C++ constructor or a C function
5629 returning a BLKmode structure), then stack_usage_map is
5630 insufficient and expand_call must push the stack around the
5631 function call. Such arguments have pass_on_stack == 1.
5633 Note that it is always safe to set stack_arg_under_construction,
5634 but this generates suboptimal code if set when not needed. */
5636 if (arg
->pass_on_stack
)
5637 stack_arg_under_construction
++;
5639 arg
->value
= expand_expr (pval
,
5641 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
5642 ? NULL_RTX
: arg
->stack
,
5643 VOIDmode
, EXPAND_STACK_PARM
);
5645 /* If we are promoting object (or for any other reason) the mode
5646 doesn't agree, convert the mode. */
5648 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
5649 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
5650 arg
->value
, arg
->unsignedp
);
5652 if (arg
->pass_on_stack
)
5653 stack_arg_under_construction
--;
5656 /* Check for overlap with already clobbered argument area. */
5657 if ((flags
& ECF_SIBCALL
)
5658 && MEM_P (arg
->value
)
5659 && mem_might_overlap_already_clobbered_arg_p (XEXP (arg
->value
, 0),
5660 arg
->locate
.size
.constant
))
5661 sibcall_failure
= 1;
5663 /* Don't allow anything left on stack from computation
5664 of argument to alloca. */
5665 if (flags
& ECF_MAY_BE_ALLOCA
)
5666 do_pending_stack_adjust ();
5668 if (arg
->value
== arg
->stack
)
5669 /* If the value is already in the stack slot, we are done. */
5671 else if (arg
->mode
!= BLKmode
)
5673 unsigned int parm_align
;
5675 /* Argument is a scalar, not entirely passed in registers.
5676 (If part is passed in registers, arg->partial says how much
5677 and emit_push_insn will take care of putting it there.)
5679 Push it, and if its size is less than the
5680 amount of space allocated to it,
5681 also bump stack pointer by the additional space.
5682 Note that in C the default argument promotions
5683 will prevent such mismatches. */
5685 poly_int64 size
= (TYPE_EMPTY_P (TREE_TYPE (pval
))
5686 ? 0 : GET_MODE_SIZE (arg
->mode
));
5688 /* Compute how much space the push instruction will push.
5689 On many machines, pushing a byte will advance the stack
5690 pointer by a halfword. */
5691 #ifdef PUSH_ROUNDING
5692 size
= PUSH_ROUNDING (size
);
5696 /* Compute how much space the argument should get:
5697 round up to a multiple of the alignment for arguments. */
5698 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5700 /* At the moment we don't (need to) support ABIs for which the
5701 padding isn't known at compile time. In principle it should
5702 be easy to add though. */
5703 used
= force_align_up (size
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
5705 /* Compute the alignment of the pushed argument. */
5706 parm_align
= arg
->locate
.boundary
;
5707 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5710 poly_int64 pad
= used
- size
;
5711 unsigned int pad_align
= known_alignment (pad
) * BITS_PER_UNIT
;
5713 parm_align
= MIN (parm_align
, pad_align
);
5716 /* This isn't already where we want it on the stack, so put it there.
5717 This can either be done with push or copy insns. */
5718 if (maybe_ne (used
, 0)
5719 && !emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
),
5720 NULL_RTX
, parm_align
, partial
, reg
, used
- size
,
5721 argblock
, ARGS_SIZE_RTX (arg
->locate
.offset
),
5722 reg_parm_stack_space
,
5723 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
), true))
5724 sibcall_failure
= 1;
5726 /* Unless this is a partially-in-register argument, the argument is now
5729 arg
->value
= arg
->stack
;
5733 /* BLKmode, at least partly to be pushed. */
5735 unsigned int parm_align
;
5739 /* Pushing a nonscalar.
5740 If part is passed in registers, PARTIAL says how much
5741 and emit_push_insn will take care of putting it there. */
5743 /* Round its size up to a multiple
5744 of the allocation unit for arguments. */
5746 if (arg
->locate
.size
.var
!= 0)
5749 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
5753 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
5754 for BLKmode is careful to avoid it. */
5755 excess
= (arg
->locate
.size
.constant
5756 - arg_int_size_in_bytes (TREE_TYPE (pval
))
5758 size_rtx
= expand_expr (arg_size_in_bytes (TREE_TYPE (pval
)),
5759 NULL_RTX
, TYPE_MODE (sizetype
),
5763 parm_align
= arg
->locate
.boundary
;
5765 /* When an argument is padded down, the block is aligned to
5766 PARM_BOUNDARY, but the actual argument isn't. */
5767 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5770 if (arg
->locate
.size
.var
)
5771 parm_align
= BITS_PER_UNIT
;
5774 unsigned int excess_align
5775 = known_alignment (excess
) * BITS_PER_UNIT
;
5776 if (excess_align
!= 0)
5777 parm_align
= MIN (parm_align
, excess_align
);
5781 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
5783 /* emit_push_insn might not work properly if arg->value and
5784 argblock + arg->locate.offset areas overlap. */
5788 if (strip_offset (XEXP (x
, 0), &i
)
5789 == crtl
->args
.internal_arg_pointer
)
5791 /* arg.locate doesn't contain the pretend_args_size offset,
5792 it's part of argblock. Ensure we don't count it in I. */
5793 if (STACK_GROWS_DOWNWARD
)
5794 i
-= crtl
->args
.pretend_args_size
;
5796 i
+= crtl
->args
.pretend_args_size
;
5798 /* expand_call should ensure this. */
5799 gcc_assert (!arg
->locate
.offset
.var
5800 && arg
->locate
.size
.var
== 0);
5801 poly_int64 size_val
= rtx_to_poly_int64 (size_rtx
);
5803 if (known_eq (arg
->locate
.offset
.constant
, i
))
5805 /* Even though they appear to be at the same location,
5806 if part of the outgoing argument is in registers,
5807 they aren't really at the same location. Check for
5808 this by making sure that the incoming size is the
5809 same as the outgoing size. */
5810 if (maybe_ne (arg
->locate
.size
.constant
, size_val
))
5811 sibcall_failure
= 1;
5813 else if (maybe_in_range_p (arg
->locate
.offset
.constant
,
5815 sibcall_failure
= 1;
5816 /* Use arg->locate.size.constant instead of size_rtx
5817 because we only care about the part of the argument
5819 else if (maybe_in_range_p (i
, arg
->locate
.offset
.constant
,
5820 arg
->locate
.size
.constant
))
5821 sibcall_failure
= 1;
5825 if (!CONST_INT_P (size_rtx
) || INTVAL (size_rtx
) != 0)
5826 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
5827 parm_align
, partial
, reg
, excess
, argblock
,
5828 ARGS_SIZE_RTX (arg
->locate
.offset
),
5829 reg_parm_stack_space
,
5830 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
), false);
5832 /* Unless this is a partially-in-register argument, the argument is now
5835 ??? Unlike the case above, in which we want the actual
5836 address of the data, so that we can load it directly into a
5837 register, here we want the address of the stack slot, so that
5838 it's properly aligned for word-by-word copying or something
5839 like that. It's not clear that this is always correct. */
5841 arg
->value
= arg
->stack_slot
;
5844 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
5846 tree type
= TREE_TYPE (arg
->tree_value
);
5848 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
5849 int_size_in_bytes (type
));
5852 /* Mark all slots this store used. */
5853 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
5854 && argblock
&& ! variable_size
&& arg
->stack
)
5855 mark_stack_region_used (lower_bound
, upper_bound
);
5857 /* Once we have pushed something, pops can't safely
5858 be deferred during the rest of the arguments. */
5861 /* Free any temporary slots made in processing this argument. */
5864 return sibcall_failure
;
5867 /* Nonzero if we do not know how to pass ARG solely in registers. */
5870 must_pass_in_stack_var_size (const function_arg_info
&arg
)
5875 /* If the type has variable size... */
5876 if (TREE_CODE (TYPE_SIZE (arg
.type
)) != INTEGER_CST
)
5879 /* If the type is marked as addressable (it is required
5880 to be constructed into the stack)... */
5881 if (TREE_ADDRESSABLE (arg
.type
))
5887 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5888 takes trailing padding of a structure into account. */
5889 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5892 must_pass_in_stack_var_size_or_pad (const function_arg_info
&arg
)
5897 /* If the type has variable size... */
5898 if (TREE_CODE (TYPE_SIZE (arg
.type
)) != INTEGER_CST
)
5901 /* If the type is marked as addressable (it is required
5902 to be constructed into the stack)... */
5903 if (TREE_ADDRESSABLE (arg
.type
))
5906 if (TYPE_EMPTY_P (arg
.type
))
5909 /* If the padding and mode of the type is such that a copy into
5910 a register would put it into the wrong part of the register. */
5911 if (arg
.mode
== BLKmode
5912 && int_size_in_bytes (arg
.type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
5913 && (targetm
.calls
.function_arg_padding (arg
.mode
, arg
.type
)
5914 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
5920 /* Return true if TYPE must be passed on the stack when passed to
5921 the "..." arguments of a function. */
5924 must_pass_va_arg_in_stack (tree type
)
5926 function_arg_info
arg (type
, /*named=*/false);
5927 return targetm
.calls
.must_pass_in_stack (arg
);
5930 /* Tell the garbage collector about GTY markers in this source file. */
5931 #include "gt-calls.h"