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 /* Return true if ARG, which is passed by reference, should be callee
939 copied instead of caller copied. */
942 reference_callee_copied (CUMULATIVE_ARGS
*ca
, const function_arg_info
&arg
)
944 if (arg
.type
&& TREE_ADDRESSABLE (arg
.type
))
946 return targetm
.calls
.callee_copies (pack_cumulative_args (ca
), arg
);
950 /* Precompute all register parameters as described by ARGS, storing values
951 into fields within the ARGS array.
953 NUM_ACTUALS indicates the total number elements in the ARGS array.
955 Set REG_PARM_SEEN if we encounter a register parameter. */
958 precompute_register_parameters (int num_actuals
, struct arg_data
*args
,
965 for (i
= 0; i
< num_actuals
; i
++)
966 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
970 if (args
[i
].value
== 0)
973 args
[i
].value
= expand_normal (args
[i
].tree_value
);
974 preserve_temp_slots (args
[i
].value
);
978 /* If we are to promote the function arg to a wider mode,
981 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
983 = convert_modes (args
[i
].mode
,
984 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
985 args
[i
].value
, args
[i
].unsignedp
);
987 /* If the value is a non-legitimate constant, force it into a
988 pseudo now. TLS symbols sometimes need a call to resolve. */
989 if (CONSTANT_P (args
[i
].value
)
990 && !targetm
.legitimate_constant_p (args
[i
].mode
, args
[i
].value
))
991 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
993 /* If we're going to have to load the value by parts, pull the
994 parts into pseudos. The part extraction process can involve
995 non-trivial computation. */
996 if (GET_CODE (args
[i
].reg
) == PARALLEL
)
998 tree type
= TREE_TYPE (args
[i
].tree_value
);
999 args
[i
].parallel_value
1000 = emit_group_load_into_temps (args
[i
].reg
, args
[i
].value
,
1001 type
, int_size_in_bytes (type
));
1004 /* If the value is expensive, and we are inside an appropriately
1005 short loop, put the value into a pseudo and then put the pseudo
1008 For small register classes, also do this if this call uses
1009 register parameters. This is to avoid reload conflicts while
1010 loading the parameters registers. */
1012 else if ((! (REG_P (args
[i
].value
)
1013 || (GET_CODE (args
[i
].value
) == SUBREG
1014 && REG_P (SUBREG_REG (args
[i
].value
)))))
1015 && args
[i
].mode
!= BLKmode
1016 && (set_src_cost (args
[i
].value
, args
[i
].mode
,
1017 optimize_insn_for_speed_p ())
1018 > COSTS_N_INSNS (1))
1020 && targetm
.small_register_classes_for_mode_p (args
[i
].mode
))
1022 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
1026 #ifdef REG_PARM_STACK_SPACE
1028 /* The argument list is the property of the called routine and it
1029 may clobber it. If the fixed area has been used for previous
1030 parameters, we must save and restore it. */
1033 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
1038 /* Compute the boundary of the area that needs to be saved, if any. */
1039 high
= reg_parm_stack_space
;
1040 if (ARGS_GROW_DOWNWARD
)
1043 if (high
> highest_outgoing_arg_in_use
)
1044 high
= highest_outgoing_arg_in_use
;
1046 for (low
= 0; low
< high
; low
++)
1047 if (stack_usage_map
[low
] != 0 || low
>= stack_usage_watermark
)
1050 machine_mode save_mode
;
1056 while (stack_usage_map
[--high
] == 0)
1060 *high_to_save
= high
;
1062 num_to_save
= high
- low
+ 1;
1064 /* If we don't have the required alignment, must do this
1066 scalar_int_mode imode
;
1067 if (int_mode_for_size (num_to_save
* BITS_PER_UNIT
, 1).exists (&imode
)
1068 && (low
& (MIN (GET_MODE_SIZE (imode
),
1069 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)) == 0)
1072 save_mode
= BLKmode
;
1074 if (ARGS_GROW_DOWNWARD
)
1079 addr
= plus_constant (Pmode
, argblock
, delta
);
1080 stack_area
= gen_rtx_MEM (save_mode
, memory_address (save_mode
, addr
));
1082 set_mem_align (stack_area
, PARM_BOUNDARY
);
1083 if (save_mode
== BLKmode
)
1085 save_area
= assign_stack_temp (BLKmode
, num_to_save
);
1086 emit_block_move (validize_mem (save_area
), stack_area
,
1087 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
1091 save_area
= gen_reg_rtx (save_mode
);
1092 emit_move_insn (save_area
, stack_area
);
1102 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
1104 machine_mode save_mode
= GET_MODE (save_area
);
1106 rtx addr
, stack_area
;
1108 if (ARGS_GROW_DOWNWARD
)
1109 delta
= -high_to_save
;
1111 delta
= low_to_save
;
1113 addr
= plus_constant (Pmode
, argblock
, delta
);
1114 stack_area
= gen_rtx_MEM (save_mode
, memory_address (save_mode
, addr
));
1115 set_mem_align (stack_area
, PARM_BOUNDARY
);
1117 if (save_mode
!= BLKmode
)
1118 emit_move_insn (stack_area
, save_area
);
1120 emit_block_move (stack_area
, validize_mem (save_area
),
1121 GEN_INT (high_to_save
- low_to_save
+ 1),
1122 BLOCK_OP_CALL_PARM
);
1124 #endif /* REG_PARM_STACK_SPACE */
1126 /* If any elements in ARGS refer to parameters that are to be passed in
1127 registers, but not in memory, and whose alignment does not permit a
1128 direct copy into registers. Copy the values into a group of pseudos
1129 which we will later copy into the appropriate hard registers.
1131 Pseudos for each unaligned argument will be stored into the array
1132 args[argnum].aligned_regs. The caller is responsible for deallocating
1133 the aligned_regs array if it is nonzero. */
1136 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
1140 for (i
= 0; i
< num_actuals
; i
++)
1141 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
1142 && GET_CODE (args
[i
].reg
) != PARALLEL
1143 && args
[i
].mode
== BLKmode
1144 && MEM_P (args
[i
].value
)
1145 && (MEM_ALIGN (args
[i
].value
)
1146 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
1148 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1149 int endian_correction
= 0;
1151 if (args
[i
].partial
)
1153 gcc_assert (args
[i
].partial
% UNITS_PER_WORD
== 0);
1154 args
[i
].n_aligned_regs
= args
[i
].partial
/ UNITS_PER_WORD
;
1158 args
[i
].n_aligned_regs
1159 = (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
1162 args
[i
].aligned_regs
= XNEWVEC (rtx
, args
[i
].n_aligned_regs
);
1164 /* Structures smaller than a word are normally aligned to the
1165 least significant byte. On a BYTES_BIG_ENDIAN machine,
1166 this means we must skip the empty high order bytes when
1167 calculating the bit offset. */
1168 if (bytes
< UNITS_PER_WORD
1169 #ifdef BLOCK_REG_PADDING
1170 && (BLOCK_REG_PADDING (args
[i
].mode
,
1171 TREE_TYPE (args
[i
].tree_value
), 1)
1177 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
1179 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1181 rtx reg
= gen_reg_rtx (word_mode
);
1182 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
1183 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
1185 args
[i
].aligned_regs
[j
] = reg
;
1186 word
= extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
1187 word_mode
, word_mode
, false, NULL
);
1189 /* There is no need to restrict this code to loading items
1190 in TYPE_ALIGN sized hunks. The bitfield instructions can
1191 load up entire word sized registers efficiently.
1193 ??? This may not be needed anymore.
1194 We use to emit a clobber here but that doesn't let later
1195 passes optimize the instructions we emit. By storing 0 into
1196 the register later passes know the first AND to zero out the
1197 bitfield being set in the register is unnecessary. The store
1198 of 0 will be deleted as will at least the first AND. */
1200 emit_move_insn (reg
, const0_rtx
);
1202 bytes
-= bitsize
/ BITS_PER_UNIT
;
1203 store_bit_field (reg
, bitsize
, endian_correction
, 0, 0,
1204 word_mode
, word
, false);
1209 /* The limit set by -Walloc-larger-than=. */
1210 static GTY(()) tree alloc_object_size_limit
;
1212 /* Initialize ALLOC_OBJECT_SIZE_LIMIT based on the -Walloc-size-larger-than=
1213 setting if the option is specified, or to the maximum object size if it
1214 is not. Return the initialized value. */
1217 alloc_max_size (void)
1219 if (alloc_object_size_limit
)
1220 return alloc_object_size_limit
;
1222 HOST_WIDE_INT limit
= warn_alloc_size_limit
;
1223 if (limit
== HOST_WIDE_INT_MAX
)
1224 limit
= tree_to_shwi (TYPE_MAX_VALUE (ptrdiff_type_node
));
1226 alloc_object_size_limit
= build_int_cst (size_type_node
, limit
);
1228 return alloc_object_size_limit
;
1231 /* Return true when EXP's range can be determined and set RANGE[] to it
1232 after adjusting it if necessary to make EXP a represents a valid size
1233 of object, or a valid size argument to an allocation function declared
1234 with attribute alloc_size (whose argument may be signed), or to a string
1235 manipulation function like memset. When ALLOW_ZERO is true, allow
1236 returning a range of [0, 0] for a size in an anti-range [1, N] where
1237 N > PTRDIFF_MAX. A zero range is a (nearly) invalid argument to
1238 allocation functions like malloc but it is a valid argument to
1239 functions like memset. */
1242 get_size_range (tree exp
, tree range
[2], bool allow_zero
/* = false */)
1244 if (tree_fits_uhwi_p (exp
))
1246 /* EXP is a constant. */
1247 range
[0] = range
[1] = exp
;
1251 tree exptype
= TREE_TYPE (exp
);
1252 bool integral
= INTEGRAL_TYPE_P (exptype
);
1255 enum value_range_kind range_type
;
1258 range_type
= determine_value_range (exp
, &min
, &max
);
1260 range_type
= VR_VARYING
;
1262 if (range_type
== VR_VARYING
)
1266 /* Use the full range of the type of the expression when
1267 no value range information is available. */
1268 range
[0] = TYPE_MIN_VALUE (exptype
);
1269 range
[1] = TYPE_MAX_VALUE (exptype
);
1273 range
[0] = NULL_TREE
;
1274 range
[1] = NULL_TREE
;
1278 unsigned expprec
= TYPE_PRECISION (exptype
);
1280 bool signed_p
= !TYPE_UNSIGNED (exptype
);
1282 if (range_type
== VR_ANTI_RANGE
)
1286 if (wi::les_p (max
, 0))
1288 /* EXP is not in a strictly negative range. That means
1289 it must be in some (not necessarily strictly) positive
1290 range which includes zero. Since in signed to unsigned
1291 conversions negative values end up converted to large
1292 positive values, and otherwise they are not valid sizes,
1293 the resulting range is in both cases [0, TYPE_MAX]. */
1294 min
= wi::zero (expprec
);
1295 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1297 else if (wi::les_p (min
- 1, 0))
1299 /* EXP is not in a negative-positive range. That means EXP
1300 is either negative, or greater than max. Since negative
1301 sizes are invalid make the range [MAX + 1, TYPE_MAX]. */
1303 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1308 min
= wi::zero (expprec
);
1311 else if (wi::eq_p (0, min
- 1))
1313 /* EXP is unsigned and not in the range [1, MAX]. That means
1314 it's either zero or greater than MAX. Even though 0 would
1315 normally be detected by -Walloc-zero, unless ALLOW_ZERO
1316 is true, set the range to [MAX, TYPE_MAX] so that when MAX
1317 is greater than the limit the whole range is diagnosed. */
1319 min
= max
= wi::zero (expprec
);
1323 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1329 min
= wi::zero (expprec
);
1333 range
[0] = wide_int_to_tree (exptype
, min
);
1334 range
[1] = wide_int_to_tree (exptype
, max
);
1339 /* Diagnose a call EXP to function FN decorated with attribute alloc_size
1340 whose argument numbers given by IDX with values given by ARGS exceed
1341 the maximum object size or cause an unsigned oveflow (wrapping) when
1342 multiplied. FN is null when EXP is a call via a function pointer.
1343 When ARGS[0] is null the function does nothing. ARGS[1] may be null
1344 for functions like malloc, and non-null for those like calloc that
1345 are decorated with a two-argument attribute alloc_size. */
1348 maybe_warn_alloc_args_overflow (tree fn
, tree exp
, tree args
[2], int idx
[2])
1350 /* The range each of the (up to) two arguments is known to be in. */
1351 tree argrange
[2][2] = { { NULL_TREE
, NULL_TREE
}, { NULL_TREE
, NULL_TREE
} };
1353 /* Maximum object size set by -Walloc-size-larger-than= or SIZE_MAX / 2. */
1354 tree maxobjsize
= alloc_max_size ();
1356 location_t loc
= EXPR_LOCATION (exp
);
1358 tree fntype
= fn
? TREE_TYPE (fn
) : TREE_TYPE (TREE_TYPE (exp
));
1359 bool warned
= false;
1361 /* Validate each argument individually. */
1362 for (unsigned i
= 0; i
!= 2 && args
[i
]; ++i
)
1364 if (TREE_CODE (args
[i
]) == INTEGER_CST
)
1366 argrange
[i
][0] = args
[i
];
1367 argrange
[i
][1] = args
[i
];
1369 if (tree_int_cst_lt (args
[i
], integer_zero_node
))
1371 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1372 "%Kargument %i value %qE is negative",
1373 exp
, idx
[i
] + 1, args
[i
]);
1375 else if (integer_zerop (args
[i
]))
1377 /* Avoid issuing -Walloc-zero for allocation functions other
1378 than __builtin_alloca that are declared with attribute
1379 returns_nonnull because there's no portability risk. This
1380 avoids warning for such calls to libiberty's xmalloc and
1382 Also avoid issuing the warning for calls to function named
1384 if (fn
&& fndecl_built_in_p (fn
, BUILT_IN_ALLOCA
)
1385 ? IDENTIFIER_LENGTH (DECL_NAME (fn
)) != 6
1386 : !lookup_attribute ("returns_nonnull",
1387 TYPE_ATTRIBUTES (fntype
)))
1388 warned
= warning_at (loc
, OPT_Walloc_zero
,
1389 "%Kargument %i value is zero",
1392 else if (tree_int_cst_lt (maxobjsize
, args
[i
]))
1394 /* G++ emits calls to ::operator new[](SIZE_MAX) in C++98
1395 mode and with -fno-exceptions as a way to indicate array
1396 size overflow. There's no good way to detect C++98 here
1397 so avoid diagnosing these calls for all C++ modes. */
1402 && DECL_IS_OPERATOR_NEW_P (fn
)
1403 && integer_all_onesp (args
[i
]))
1406 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1407 "%Kargument %i value %qE exceeds "
1408 "maximum object size %E",
1409 exp
, idx
[i
] + 1, args
[i
], maxobjsize
);
1412 else if (TREE_CODE (args
[i
]) == SSA_NAME
1413 && get_size_range (args
[i
], argrange
[i
]))
1415 /* Verify that the argument's range is not negative (including
1416 upper bound of zero). */
1417 if (tree_int_cst_lt (argrange
[i
][0], integer_zero_node
)
1418 && tree_int_cst_le (argrange
[i
][1], integer_zero_node
))
1420 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1421 "%Kargument %i range [%E, %E] is negative",
1423 argrange
[i
][0], argrange
[i
][1]);
1425 else if (tree_int_cst_lt (maxobjsize
, argrange
[i
][0]))
1427 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1428 "%Kargument %i range [%E, %E] exceeds "
1429 "maximum object size %E",
1431 argrange
[i
][0], argrange
[i
][1],
1440 /* For a two-argument alloc_size, validate the product of the two
1441 arguments if both of their values or ranges are known. */
1442 if (!warned
&& tree_fits_uhwi_p (argrange
[0][0])
1443 && argrange
[1][0] && tree_fits_uhwi_p (argrange
[1][0])
1444 && !integer_onep (argrange
[0][0])
1445 && !integer_onep (argrange
[1][0]))
1447 /* Check for overflow in the product of a function decorated with
1448 attribute alloc_size (X, Y). */
1449 unsigned szprec
= TYPE_PRECISION (size_type_node
);
1450 wide_int x
= wi::to_wide (argrange
[0][0], szprec
);
1451 wide_int y
= wi::to_wide (argrange
[1][0], szprec
);
1453 wi::overflow_type vflow
;
1454 wide_int prod
= wi::umul (x
, y
, &vflow
);
1457 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1458 "%Kproduct %<%E * %E%> of arguments %i and %i "
1459 "exceeds %<SIZE_MAX%>",
1460 exp
, argrange
[0][0], argrange
[1][0],
1461 idx
[0] + 1, idx
[1] + 1);
1462 else if (wi::ltu_p (wi::to_wide (maxobjsize
, szprec
), prod
))
1463 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1464 "%Kproduct %<%E * %E%> of arguments %i and %i "
1465 "exceeds maximum object size %E",
1466 exp
, argrange
[0][0], argrange
[1][0],
1467 idx
[0] + 1, idx
[1] + 1,
1472 /* Print the full range of each of the two arguments to make
1473 it clear when it is, in fact, in a range and not constant. */
1474 if (argrange
[0][0] != argrange
[0][1])
1475 inform (loc
, "argument %i in the range [%E, %E]",
1476 idx
[0] + 1, argrange
[0][0], argrange
[0][1]);
1477 if (argrange
[1][0] != argrange
[1][1])
1478 inform (loc
, "argument %i in the range [%E, %E]",
1479 idx
[1] + 1, argrange
[1][0], argrange
[1][1]);
1485 location_t fnloc
= DECL_SOURCE_LOCATION (fn
);
1487 if (DECL_IS_BUILTIN (fn
))
1489 "in a call to built-in allocation function %qD", fn
);
1492 "in a call to allocation function %qD declared here", fn
);
1496 /* If EXPR refers to a character array or pointer declared attribute
1497 nonstring return a decl for that array or pointer and set *REF to
1498 the referenced enclosing object or pointer. Otherwise returns
1502 get_attr_nonstring_decl (tree expr
, tree
*ref
)
1505 tree var
= NULL_TREE
;
1506 if (TREE_CODE (decl
) == SSA_NAME
)
1508 gimple
*def
= SSA_NAME_DEF_STMT (decl
);
1510 if (is_gimple_assign (def
))
1512 tree_code code
= gimple_assign_rhs_code (def
);
1513 if (code
== ADDR_EXPR
1514 || code
== COMPONENT_REF
1515 || code
== VAR_DECL
)
1516 decl
= gimple_assign_rhs1 (def
);
1519 var
= SSA_NAME_VAR (decl
);
1522 if (TREE_CODE (decl
) == ADDR_EXPR
)
1523 decl
= TREE_OPERAND (decl
, 0);
1525 /* To simplify calling code, store the referenced DECL regardless of
1526 the attribute determined below, but avoid storing the SSA_NAME_VAR
1527 obtained above (it's not useful for dataflow purposes). */
1531 /* Use the SSA_NAME_VAR that was determined above to see if it's
1532 declared nonstring. Otherwise drill down into the referenced
1536 else if (TREE_CODE (decl
) == ARRAY_REF
)
1537 decl
= TREE_OPERAND (decl
, 0);
1538 else if (TREE_CODE (decl
) == COMPONENT_REF
)
1539 decl
= TREE_OPERAND (decl
, 1);
1540 else if (TREE_CODE (decl
) == MEM_REF
)
1541 return get_attr_nonstring_decl (TREE_OPERAND (decl
, 0), ref
);
1544 && lookup_attribute ("nonstring", DECL_ATTRIBUTES (decl
)))
1550 /* Warn about passing a non-string array/pointer to a function that
1551 expects a nul-terminated string argument. */
1554 maybe_warn_nonstring_arg (tree fndecl
, tree exp
)
1556 if (!fndecl
|| !fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
1559 if (TREE_NO_WARNING (exp
) || !warn_stringop_overflow
)
1562 /* Avoid clearly invalid calls (more checking done below). */
1563 unsigned nargs
= call_expr_nargs (exp
);
1567 /* The bound argument to a bounded string function like strncpy. */
1568 tree bound
= NULL_TREE
;
1570 /* The longest known or possible string argument to one of the comparison
1571 functions. If the length is less than the bound it is used instead.
1572 Since the length is only used for warning and not for code generation
1573 disable strict mode in the calls to get_range_strlen below. */
1574 tree maxlen
= NULL_TREE
;
1576 /* It's safe to call "bounded" string functions with a non-string
1577 argument since the functions provide an explicit bound for this
1578 purpose. The exception is strncat where the bound may refer to
1579 either the destination or the source. */
1580 int fncode
= DECL_FUNCTION_CODE (fndecl
);
1583 case BUILT_IN_STRCMP
:
1584 case BUILT_IN_STRNCMP
:
1585 case BUILT_IN_STRNCASECMP
:
1587 /* For these, if one argument refers to one or more of a set
1588 of string constants or arrays of known size, determine
1589 the range of their known or possible lengths and use it
1590 conservatively as the bound for the unbounded function,
1591 and to adjust the range of the bound of the bounded ones. */
1592 for (unsigned argno
= 0;
1593 argno
< MIN (nargs
, 2)
1594 && !(maxlen
&& TREE_CODE (maxlen
) == INTEGER_CST
); argno
++)
1596 tree arg
= CALL_EXPR_ARG (exp
, argno
);
1597 if (!get_attr_nonstring_decl (arg
))
1599 c_strlen_data lendata
= { };
1600 get_range_strlen (arg
, &lendata
, /* eltsize = */ 1);
1601 maxlen
= lendata
.maxbound
;
1607 case BUILT_IN_STRNCAT
:
1608 case BUILT_IN_STPNCPY
:
1609 case BUILT_IN_STRNCPY
:
1611 bound
= CALL_EXPR_ARG (exp
, 2);
1614 case BUILT_IN_STRNDUP
:
1616 bound
= CALL_EXPR_ARG (exp
, 1);
1619 case BUILT_IN_STRNLEN
:
1621 tree arg
= CALL_EXPR_ARG (exp
, 0);
1622 if (!get_attr_nonstring_decl (arg
))
1624 c_strlen_data lendata
= { };
1625 get_range_strlen (arg
, &lendata
, /* eltsize = */ 1);
1626 maxlen
= lendata
.maxbound
;
1629 bound
= CALL_EXPR_ARG (exp
, 1);
1637 /* Determine the range of the bound argument (if specified). */
1638 tree bndrng
[2] = { NULL_TREE
, NULL_TREE
};
1642 get_size_range (bound
, bndrng
);
1645 location_t loc
= EXPR_LOCATION (exp
);
1649 /* Diagnose excessive bound prior the adjustment below and
1650 regardless of attribute nonstring. */
1651 tree maxobjsize
= max_object_size ();
1652 if (tree_int_cst_lt (maxobjsize
, bndrng
[0]))
1654 if (tree_int_cst_equal (bndrng
[0], bndrng
[1]))
1655 warning_at (loc
, OPT_Wstringop_overflow_
,
1656 "%K%qD specified bound %E "
1657 "exceeds maximum object size %E",
1658 exp
, fndecl
, bndrng
[0], maxobjsize
);
1660 warning_at (loc
, OPT_Wstringop_overflow_
,
1661 "%K%qD specified bound [%E, %E] "
1662 "exceeds maximum object size %E",
1663 exp
, fndecl
, bndrng
[0], bndrng
[1], maxobjsize
);
1668 if (maxlen
&& !integer_all_onesp (maxlen
))
1670 /* Add one for the nul. */
1671 maxlen
= const_binop (PLUS_EXPR
, TREE_TYPE (maxlen
), maxlen
,
1676 /* Conservatively use the upper bound of the lengths for
1677 both the lower and the upper bound of the operation. */
1680 bound
= void_type_node
;
1684 /* Replace the bound on the operation with the upper bound
1685 of the length of the string if the latter is smaller. */
1686 if (tree_int_cst_lt (maxlen
, bndrng
[0]))
1688 else if (tree_int_cst_lt (maxlen
, bndrng
[1]))
1693 /* Iterate over the built-in function's formal arguments and check
1694 each const char* against the actual argument. If the actual
1695 argument is declared attribute non-string issue a warning unless
1696 the argument's maximum length is bounded. */
1697 function_args_iterator it
;
1698 function_args_iter_init (&it
, TREE_TYPE (fndecl
));
1700 for (unsigned argno
= 0; ; ++argno
, function_args_iter_next (&it
))
1702 /* Avoid iterating past the declared argument in a call
1703 to function declared without a prototype. */
1707 tree argtype
= function_args_iter_cond (&it
);
1711 if (TREE_CODE (argtype
) != POINTER_TYPE
)
1714 argtype
= TREE_TYPE (argtype
);
1716 if (TREE_CODE (argtype
) != INTEGER_TYPE
1717 || !TYPE_READONLY (argtype
))
1720 argtype
= TYPE_MAIN_VARIANT (argtype
);
1721 if (argtype
!= char_type_node
)
1724 tree callarg
= CALL_EXPR_ARG (exp
, argno
);
1725 if (TREE_CODE (callarg
) == ADDR_EXPR
)
1726 callarg
= TREE_OPERAND (callarg
, 0);
1728 /* See if the destination is declared with attribute "nonstring". */
1729 tree decl
= get_attr_nonstring_decl (callarg
);
1733 /* The maximum number of array elements accessed. */
1734 offset_int wibnd
= 0;
1736 if (argno
&& fncode
== BUILT_IN_STRNCAT
)
1738 /* See if the bound in strncat is derived from the length
1739 of the strlen of the destination (as it's expected to be).
1740 If so, reset BOUND and FNCODE to trigger a warning. */
1741 tree dstarg
= CALL_EXPR_ARG (exp
, 0);
1742 if (is_strlen_related_p (dstarg
, bound
))
1744 /* The bound applies to the destination, not to the source,
1745 so reset these to trigger a warning without mentioning
1751 /* Use the upper bound of the range for strncat. */
1752 wibnd
= wi::to_offset (bndrng
[1]);
1755 /* Use the lower bound of the range for functions other than
1757 wibnd
= wi::to_offset (bndrng
[0]);
1759 /* Determine the size of the argument array if it is one. */
1760 offset_int asize
= wibnd
;
1761 bool known_size
= false;
1762 tree type
= TREE_TYPE (decl
);
1764 /* Determine the array size. For arrays of unknown bound and
1765 pointers reset BOUND to trigger the appropriate warning. */
1766 if (TREE_CODE (type
) == ARRAY_TYPE
)
1768 if (tree arrbnd
= TYPE_DOMAIN (type
))
1770 if ((arrbnd
= TYPE_MAX_VALUE (arrbnd
)))
1772 asize
= wi::to_offset (arrbnd
) + 1;
1776 else if (bound
== void_type_node
)
1779 else if (bound
== void_type_node
)
1782 /* In a call to strncat with a bound in a range whose lower but
1783 not upper bound is less than the array size, reset ASIZE to
1784 be the same as the bound and the other variable to trigger
1785 the apprpriate warning below. */
1786 if (fncode
== BUILT_IN_STRNCAT
1787 && bndrng
[0] != bndrng
[1]
1788 && wi::ltu_p (wi::to_offset (bndrng
[0]), asize
)
1790 || wi::ltu_p (asize
, wibnd
)))
1797 bool warned
= false;
1799 auto_diagnostic_group d
;
1800 if (wi::ltu_p (asize
, wibnd
))
1802 if (bndrng
[0] == bndrng
[1])
1803 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1804 "%qD argument %i declared attribute "
1805 "%<nonstring%> is smaller than the specified "
1807 fndecl
, argno
+ 1, wibnd
.to_uhwi ());
1808 else if (wi::ltu_p (asize
, wi::to_offset (bndrng
[0])))
1809 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1810 "%qD argument %i declared attribute "
1811 "%<nonstring%> is smaller than "
1812 "the specified bound [%E, %E]",
1813 fndecl
, argno
+ 1, bndrng
[0], bndrng
[1]);
1815 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1816 "%qD argument %i declared attribute "
1817 "%<nonstring%> may be smaller than "
1818 "the specified bound [%E, %E]",
1819 fndecl
, argno
+ 1, bndrng
[0], bndrng
[1]);
1821 else if (fncode
== BUILT_IN_STRNCAT
)
1822 ; /* Avoid warning for calls to strncat() when the bound
1823 is equal to the size of the non-string argument. */
1825 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1826 "%qD argument %i declared attribute %<nonstring%>",
1830 inform (DECL_SOURCE_LOCATION (decl
),
1831 "argument %qD declared here", decl
);
1835 /* Issue an error if CALL_EXPR was flagged as requiring
1836 tall-call optimization. */
1839 maybe_complain_about_tail_call (tree call_expr
, const char *reason
)
1841 gcc_assert (TREE_CODE (call_expr
) == CALL_EXPR
);
1842 if (!CALL_EXPR_MUST_TAIL_CALL (call_expr
))
1845 error_at (EXPR_LOCATION (call_expr
), "cannot tail-call: %s", reason
);
1848 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1851 NUM_ACTUALS is the total number of parameters.
1853 N_NAMED_ARGS is the total number of named arguments.
1855 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1858 FNDECL is the tree code for the target of this call (if known)
1860 ARGS_SO_FAR holds state needed by the target to know where to place
1863 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1864 for arguments which are passed in registers.
1866 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1867 and may be modified by this routine.
1869 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1870 flags which may be modified by this routine.
1872 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1873 that requires allocation of stack space.
1875 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1876 the thunked-to function. */
1879 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
1880 struct arg_data
*args
,
1881 struct args_size
*args_size
,
1882 int n_named_args ATTRIBUTE_UNUSED
,
1883 tree exp
, tree struct_value_addr_value
,
1884 tree fndecl
, tree fntype
,
1885 cumulative_args_t args_so_far
,
1886 int reg_parm_stack_space
,
1887 rtx
*old_stack_level
,
1888 poly_int64_pod
*old_pending_adj
,
1889 int *must_preallocate
, int *ecf_flags
,
1890 bool *may_tailcall
, bool call_from_thunk_p
)
1892 CUMULATIVE_ARGS
*args_so_far_pnt
= get_cumulative_args (args_so_far
);
1893 location_t loc
= EXPR_LOCATION (exp
);
1895 /* Count arg position in order args appear. */
1900 args_size
->constant
= 0;
1903 bitmap_obstack_initialize (NULL
);
1905 /* In this loop, we consider args in the order they are written.
1906 We fill up ARGS from the back. */
1908 i
= num_actuals
- 1;
1911 call_expr_arg_iterator iter
;
1913 bitmap slots
= NULL
;
1915 if (struct_value_addr_value
)
1917 args
[j
].tree_value
= struct_value_addr_value
;
1921 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
1923 tree argtype
= TREE_TYPE (arg
);
1925 if (targetm
.calls
.split_complex_arg
1927 && TREE_CODE (argtype
) == COMPLEX_TYPE
1928 && targetm
.calls
.split_complex_arg (argtype
))
1930 tree subtype
= TREE_TYPE (argtype
);
1931 args
[j
].tree_value
= build1 (REALPART_EXPR
, subtype
, arg
);
1933 args
[j
].tree_value
= build1 (IMAGPART_EXPR
, subtype
, arg
);
1936 args
[j
].tree_value
= arg
;
1942 BITMAP_FREE (slots
);
1945 bitmap_obstack_release (NULL
);
1947 /* Extract attribute alloc_size from the type of the called expression
1948 (which could be a function or a function pointer) and if set, store
1949 the indices of the corresponding arguments in ALLOC_IDX, and then
1950 the actual argument(s) at those indices in ALLOC_ARGS. */
1951 int alloc_idx
[2] = { -1, -1 };
1952 if (tree alloc_size
= lookup_attribute ("alloc_size",
1953 TYPE_ATTRIBUTES (fntype
)))
1955 tree args
= TREE_VALUE (alloc_size
);
1956 alloc_idx
[0] = TREE_INT_CST_LOW (TREE_VALUE (args
)) - 1;
1957 if (TREE_CHAIN (args
))
1958 alloc_idx
[1] = TREE_INT_CST_LOW (TREE_VALUE (TREE_CHAIN (args
))) - 1;
1961 /* Array for up to the two attribute alloc_size arguments. */
1962 tree alloc_args
[] = { NULL_TREE
, NULL_TREE
};
1964 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1965 for (argpos
= 0; argpos
< num_actuals
; i
--, argpos
++)
1967 tree type
= TREE_TYPE (args
[i
].tree_value
);
1971 /* Replace erroneous argument with constant zero. */
1972 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1973 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1975 /* If TYPE is a transparent union or record, pass things the way
1976 we would pass the first field of the union or record. We have
1977 already verified that the modes are the same. */
1978 if ((TREE_CODE (type
) == UNION_TYPE
|| TREE_CODE (type
) == RECORD_TYPE
)
1979 && TYPE_TRANSPARENT_AGGR (type
))
1980 type
= TREE_TYPE (first_field (type
));
1982 /* Decide where to pass this arg.
1984 args[i].reg is nonzero if all or part is passed in registers.
1986 args[i].partial is nonzero if part but not all is passed in registers,
1987 and the exact value says how many bytes are passed in registers.
1989 args[i].pass_on_stack is nonzero if the argument must at least be
1990 computed on the stack. It may then be loaded back into registers
1991 if args[i].reg is nonzero.
1993 These decisions are driven by the FUNCTION_... macros and must agree
1994 with those made by function.c. */
1996 /* See if this argument should be passed by invisible reference. */
1997 function_arg_info
orig_arg (type
, argpos
< n_named_args
);
1998 if (pass_by_reference (args_so_far_pnt
, orig_arg
))
2001 tree base
= NULL_TREE
;
2003 callee_copies
= reference_callee_copied (args_so_far_pnt
, orig_arg
);
2005 /* If we're compiling a thunk, pass through invisible references
2006 instead of making a copy. */
2007 if (call_from_thunk_p
2009 && !TREE_ADDRESSABLE (type
)
2010 && (base
= get_base_address (args
[i
].tree_value
))
2011 && TREE_CODE (base
) != SSA_NAME
2012 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
)))))
2014 /* We may have turned the parameter value into an SSA name.
2015 Go back to the original parameter so we can take the
2017 if (TREE_CODE (args
[i
].tree_value
) == SSA_NAME
)
2019 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args
[i
].tree_value
));
2020 args
[i
].tree_value
= SSA_NAME_VAR (args
[i
].tree_value
);
2021 gcc_assert (TREE_CODE (args
[i
].tree_value
) == PARM_DECL
);
2023 /* Argument setup code may have copied the value to register. We
2024 revert that optimization now because the tail call code must
2025 use the original location. */
2026 if (TREE_CODE (args
[i
].tree_value
) == PARM_DECL
2027 && !MEM_P (DECL_RTL (args
[i
].tree_value
))
2028 && DECL_INCOMING_RTL (args
[i
].tree_value
)
2029 && MEM_P (DECL_INCOMING_RTL (args
[i
].tree_value
)))
2030 set_decl_rtl (args
[i
].tree_value
,
2031 DECL_INCOMING_RTL (args
[i
].tree_value
));
2033 mark_addressable (args
[i
].tree_value
);
2035 /* We can't use sibcalls if a callee-copied argument is
2036 stored in the current function's frame. */
2037 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
2039 *may_tailcall
= false;
2040 maybe_complain_about_tail_call (exp
,
2041 "a callee-copied argument is"
2042 " stored in the current"
2043 " function's frame");
2046 args
[i
].tree_value
= build_fold_addr_expr_loc (loc
,
2047 args
[i
].tree_value
);
2048 type
= TREE_TYPE (args
[i
].tree_value
);
2050 if (*ecf_flags
& ECF_CONST
)
2051 *ecf_flags
&= ~(ECF_CONST
| ECF_LOOPING_CONST_OR_PURE
);
2055 /* We make a copy of the object and pass the address to the
2056 function being called. */
2059 if (!COMPLETE_TYPE_P (type
)
2060 || TREE_CODE (TYPE_SIZE_UNIT (type
)) != INTEGER_CST
2061 || (flag_stack_check
== GENERIC_STACK_CHECK
2062 && compare_tree_int (TYPE_SIZE_UNIT (type
),
2063 STACK_CHECK_MAX_VAR_SIZE
) > 0))
2065 /* This is a variable-sized object. Make space on the stack
2067 rtx size_rtx
= expr_size (args
[i
].tree_value
);
2069 if (*old_stack_level
== 0)
2071 emit_stack_save (SAVE_BLOCK
, old_stack_level
);
2072 *old_pending_adj
= pending_stack_adjust
;
2073 pending_stack_adjust
= 0;
2076 /* We can pass TRUE as the 4th argument because we just
2077 saved the stack pointer and will restore it right after
2079 copy
= allocate_dynamic_stack_space (size_rtx
,
2082 max_int_size_in_bytes
2085 copy
= gen_rtx_MEM (BLKmode
, copy
);
2086 set_mem_attributes (copy
, type
, 1);
2089 copy
= assign_temp (type
, 1, 0);
2091 store_expr (args
[i
].tree_value
, copy
, 0, false, false);
2093 /* Just change the const function to pure and then let
2094 the next test clear the pure based on
2096 if (*ecf_flags
& ECF_CONST
)
2098 *ecf_flags
&= ~ECF_CONST
;
2099 *ecf_flags
|= ECF_PURE
;
2102 if (!callee_copies
&& *ecf_flags
& ECF_PURE
)
2103 *ecf_flags
&= ~(ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
2106 = build_fold_addr_expr_loc (loc
, make_tree (type
, copy
));
2107 type
= TREE_TYPE (args
[i
].tree_value
);
2108 *may_tailcall
= false;
2109 maybe_complain_about_tail_call (exp
,
2110 "argument must be passed"
2115 unsignedp
= TYPE_UNSIGNED (type
);
2116 mode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
2117 fndecl
? TREE_TYPE (fndecl
) : fntype
, 0);
2119 args
[i
].unsignedp
= unsignedp
;
2120 args
[i
].mode
= mode
;
2122 targetm
.calls
.warn_parameter_passing_abi (args_so_far
, type
);
2124 function_arg_info
arg (type
, mode
, argpos
< n_named_args
);
2125 args
[i
].reg
= targetm
.calls
.function_arg (args_so_far
, arg
);
2127 if (args
[i
].reg
&& CONST_INT_P (args
[i
].reg
))
2130 /* If this is a sibling call and the machine has register windows, the
2131 register window has to be unwinded before calling the routine, so
2132 arguments have to go into the incoming registers. */
2133 if (targetm
.calls
.function_incoming_arg
!= targetm
.calls
.function_arg
)
2134 args
[i
].tail_call_reg
2135 = targetm
.calls
.function_incoming_arg (args_so_far
, arg
);
2137 args
[i
].tail_call_reg
= args
[i
].reg
;
2140 args
[i
].partial
= targetm
.calls
.arg_partial_bytes (args_so_far
, arg
);
2142 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (arg
);
2144 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
2145 it means that we are to pass this arg in the register(s) designated
2146 by the PARALLEL, but also to pass it in the stack. */
2147 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
2148 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
2149 args
[i
].pass_on_stack
= 1;
2151 /* If this is an addressable type, we must preallocate the stack
2152 since we must evaluate the object into its final location.
2154 If this is to be passed in both registers and the stack, it is simpler
2156 if (TREE_ADDRESSABLE (type
)
2157 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
2158 *must_preallocate
= 1;
2160 /* Compute the stack-size of this argument. */
2161 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
2162 || reg_parm_stack_space
> 0
2163 || args
[i
].pass_on_stack
)
2164 locate_and_pad_parm (mode
, type
,
2165 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2170 reg_parm_stack_space
,
2171 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
2172 fndecl
, args_size
, &args
[i
].locate
);
2173 #ifdef BLOCK_REG_PADDING
2175 /* The argument is passed entirely in registers. See at which
2176 end it should be padded. */
2177 args
[i
].locate
.where_pad
=
2178 BLOCK_REG_PADDING (mode
, type
,
2179 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
2182 /* Update ARGS_SIZE, the total stack space for args so far. */
2184 args_size
->constant
+= args
[i
].locate
.size
.constant
;
2185 if (args
[i
].locate
.size
.var
)
2186 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
2188 /* Increment ARGS_SO_FAR, which has info about which arg-registers
2189 have been used, etc. */
2191 /* ??? Traditionally we've passed TYPE_MODE here, instead of the
2192 promoted_mode used for function_arg above. However, the
2193 corresponding handling of incoming arguments in function.c
2194 does pass the promoted mode. */
2195 function_arg_info
arg_to_skip (type
, TYPE_MODE (type
),
2196 argpos
< n_named_args
);
2197 targetm
.calls
.function_arg_advance (args_so_far
, arg_to_skip
);
2199 /* Store argument values for functions decorated with attribute
2201 if (argpos
== alloc_idx
[0])
2202 alloc_args
[0] = args
[i
].tree_value
;
2203 else if (argpos
== alloc_idx
[1])
2204 alloc_args
[1] = args
[i
].tree_value
;
2209 /* Check the arguments of functions decorated with attribute
2211 maybe_warn_alloc_args_overflow (fndecl
, exp
, alloc_args
, alloc_idx
);
2214 /* Detect passing non-string arguments to functions expecting
2215 nul-terminated strings. */
2216 maybe_warn_nonstring_arg (fndecl
, exp
);
2219 /* Update ARGS_SIZE to contain the total size for the argument block.
2220 Return the original constant component of the argument block's size.
2222 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
2223 for arguments passed in registers. */
2226 compute_argument_block_size (int reg_parm_stack_space
,
2227 struct args_size
*args_size
,
2228 tree fndecl ATTRIBUTE_UNUSED
,
2229 tree fntype ATTRIBUTE_UNUSED
,
2230 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
2232 poly_int64 unadjusted_args_size
= args_size
->constant
;
2234 /* For accumulate outgoing args mode we don't need to align, since the frame
2235 will be already aligned. Align to STACK_BOUNDARY in order to prevent
2236 backends from generating misaligned frame sizes. */
2237 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
2238 preferred_stack_boundary
= STACK_BOUNDARY
;
2240 /* Compute the actual size of the argument block required. The variable
2241 and constant sizes must be combined, the size may have to be rounded,
2242 and there may be a minimum required size. */
2246 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
2247 args_size
->constant
= 0;
2249 preferred_stack_boundary
/= BITS_PER_UNIT
;
2250 if (preferred_stack_boundary
> 1)
2252 /* We don't handle this case yet. To handle it correctly we have
2253 to add the delta, round and subtract the delta.
2254 Currently no machine description requires this support. */
2255 gcc_assert (multiple_p (stack_pointer_delta
,
2256 preferred_stack_boundary
));
2257 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
2260 if (reg_parm_stack_space
> 0)
2263 = size_binop (MAX_EXPR
, args_size
->var
,
2264 ssize_int (reg_parm_stack_space
));
2266 /* The area corresponding to register parameters is not to count in
2267 the size of the block we need. So make the adjustment. */
2268 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2270 = size_binop (MINUS_EXPR
, args_size
->var
,
2271 ssize_int (reg_parm_stack_space
));
2276 preferred_stack_boundary
/= BITS_PER_UNIT
;
2277 if (preferred_stack_boundary
< 1)
2278 preferred_stack_boundary
= 1;
2279 args_size
->constant
= (aligned_upper_bound (args_size
->constant
2280 + stack_pointer_delta
,
2281 preferred_stack_boundary
)
2282 - stack_pointer_delta
);
2284 args_size
->constant
= upper_bound (args_size
->constant
,
2285 reg_parm_stack_space
);
2287 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2288 args_size
->constant
-= reg_parm_stack_space
;
2290 return unadjusted_args_size
;
2293 /* Precompute parameters as needed for a function call.
2295 FLAGS is mask of ECF_* constants.
2297 NUM_ACTUALS is the number of arguments.
2299 ARGS is an array containing information for each argument; this
2300 routine fills in the INITIAL_VALUE and VALUE fields for each
2301 precomputed argument. */
2304 precompute_arguments (int num_actuals
, struct arg_data
*args
)
2308 /* If this is a libcall, then precompute all arguments so that we do not
2309 get extraneous instructions emitted as part of the libcall sequence. */
2311 /* If we preallocated the stack space, and some arguments must be passed
2312 on the stack, then we must precompute any parameter which contains a
2313 function call which will store arguments on the stack.
2314 Otherwise, evaluating the parameter may clobber previous parameters
2315 which have already been stored into the stack. (we have code to avoid
2316 such case by saving the outgoing stack arguments, but it results in
2318 if (!ACCUMULATE_OUTGOING_ARGS
)
2321 for (i
= 0; i
< num_actuals
; i
++)
2326 if (TREE_CODE (args
[i
].tree_value
) != CALL_EXPR
)
2329 /* If this is an addressable type, we cannot pre-evaluate it. */
2330 type
= TREE_TYPE (args
[i
].tree_value
);
2331 gcc_assert (!TREE_ADDRESSABLE (type
));
2333 args
[i
].initial_value
= args
[i
].value
2334 = expand_normal (args
[i
].tree_value
);
2336 mode
= TYPE_MODE (type
);
2337 if (mode
!= args
[i
].mode
)
2339 int unsignedp
= args
[i
].unsignedp
;
2341 = convert_modes (args
[i
].mode
, mode
,
2342 args
[i
].value
, args
[i
].unsignedp
);
2344 /* CSE will replace this only if it contains args[i].value
2345 pseudo, so convert it down to the declared mode using
2347 if (REG_P (args
[i
].value
)
2348 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
2349 && promote_mode (type
, mode
, &unsignedp
) != args
[i
].mode
)
2351 args
[i
].initial_value
2352 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
2353 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
2354 SUBREG_PROMOTED_SET (args
[i
].initial_value
, args
[i
].unsignedp
);
2360 /* Given the current state of MUST_PREALLOCATE and information about
2361 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
2362 compute and return the final value for MUST_PREALLOCATE. */
2365 finalize_must_preallocate (int must_preallocate
, int num_actuals
,
2366 struct arg_data
*args
, struct args_size
*args_size
)
2368 /* See if we have or want to preallocate stack space.
2370 If we would have to push a partially-in-regs parm
2371 before other stack parms, preallocate stack space instead.
2373 If the size of some parm is not a multiple of the required stack
2374 alignment, we must preallocate.
2376 If the total size of arguments that would otherwise create a copy in
2377 a temporary (such as a CALL) is more than half the total argument list
2378 size, preallocation is faster.
2380 Another reason to preallocate is if we have a machine (like the m88k)
2381 where stack alignment is required to be maintained between every
2382 pair of insns, not just when the call is made. However, we assume here
2383 that such machines either do not have push insns (and hence preallocation
2384 would occur anyway) or the problem is taken care of with
2387 if (! must_preallocate
)
2389 int partial_seen
= 0;
2390 poly_int64 copy_to_evaluate_size
= 0;
2393 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
2395 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
2397 else if (partial_seen
&& args
[i
].reg
== 0)
2398 must_preallocate
= 1;
2400 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
2401 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
2402 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
2403 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
2404 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
2405 copy_to_evaluate_size
2406 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
2409 if (maybe_ne (args_size
->constant
, 0)
2410 && maybe_ge (copy_to_evaluate_size
* 2, args_size
->constant
))
2411 must_preallocate
= 1;
2413 return must_preallocate
;
2416 /* If we preallocated stack space, compute the address of each argument
2417 and store it into the ARGS array.
2419 We need not ensure it is a valid memory address here; it will be
2420 validized when it is used.
2422 ARGBLOCK is an rtx for the address of the outgoing arguments. */
2425 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
2429 rtx arg_reg
= argblock
;
2431 poly_int64 arg_offset
= 0;
2433 if (GET_CODE (argblock
) == PLUS
)
2435 arg_reg
= XEXP (argblock
, 0);
2436 arg_offset
= rtx_to_poly_int64 (XEXP (argblock
, 1));
2439 for (i
= 0; i
< num_actuals
; i
++)
2441 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
2442 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
2444 unsigned int align
, boundary
;
2445 poly_uint64 units_on_stack
= 0;
2446 machine_mode partial_mode
= VOIDmode
;
2448 /* Skip this parm if it will not be passed on the stack. */
2449 if (! args
[i
].pass_on_stack
2451 && args
[i
].partial
== 0)
2454 if (TYPE_EMPTY_P (TREE_TYPE (args
[i
].tree_value
)))
2457 addr
= simplify_gen_binary (PLUS
, Pmode
, arg_reg
, offset
);
2458 addr
= plus_constant (Pmode
, addr
, arg_offset
);
2460 if (args
[i
].partial
!= 0)
2462 /* Only part of the parameter is being passed on the stack.
2463 Generate a simple memory reference of the correct size. */
2464 units_on_stack
= args
[i
].locate
.size
.constant
;
2465 poly_uint64 bits_on_stack
= units_on_stack
* BITS_PER_UNIT
;
2466 partial_mode
= int_mode_for_size (bits_on_stack
, 1).else_blk ();
2467 args
[i
].stack
= gen_rtx_MEM (partial_mode
, addr
);
2468 set_mem_size (args
[i
].stack
, units_on_stack
);
2472 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
2473 set_mem_attributes (args
[i
].stack
,
2474 TREE_TYPE (args
[i
].tree_value
), 1);
2476 align
= BITS_PER_UNIT
;
2477 boundary
= args
[i
].locate
.boundary
;
2478 poly_int64 offset_val
;
2479 if (args
[i
].locate
.where_pad
!= PAD_DOWNWARD
)
2481 else if (poly_int_rtx_p (offset
, &offset_val
))
2483 align
= least_bit_hwi (boundary
);
2484 unsigned int offset_align
2485 = known_alignment (offset_val
) * BITS_PER_UNIT
;
2486 if (offset_align
!= 0)
2487 align
= MIN (align
, offset_align
);
2489 set_mem_align (args
[i
].stack
, align
);
2491 addr
= simplify_gen_binary (PLUS
, Pmode
, arg_reg
, slot_offset
);
2492 addr
= plus_constant (Pmode
, addr
, arg_offset
);
2494 if (args
[i
].partial
!= 0)
2496 /* Only part of the parameter is being passed on the stack.
2497 Generate a simple memory reference of the correct size.
2499 args
[i
].stack_slot
= gen_rtx_MEM (partial_mode
, addr
);
2500 set_mem_size (args
[i
].stack_slot
, units_on_stack
);
2504 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
2505 set_mem_attributes (args
[i
].stack_slot
,
2506 TREE_TYPE (args
[i
].tree_value
), 1);
2508 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
2510 /* Function incoming arguments may overlap with sibling call
2511 outgoing arguments and we cannot allow reordering of reads
2512 from function arguments with stores to outgoing arguments
2513 of sibling calls. */
2514 set_mem_alias_set (args
[i
].stack
, 0);
2515 set_mem_alias_set (args
[i
].stack_slot
, 0);
2520 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
2521 in a call instruction.
2523 FNDECL is the tree node for the target function. For an indirect call
2524 FNDECL will be NULL_TREE.
2526 ADDR is the operand 0 of CALL_EXPR for this call. */
2529 rtx_for_function_call (tree fndecl
, tree addr
)
2533 /* Get the function to call, in the form of RTL. */
2536 if (!TREE_USED (fndecl
) && fndecl
!= current_function_decl
)
2537 TREE_USED (fndecl
) = 1;
2539 /* Get a SYMBOL_REF rtx for the function address. */
2540 funexp
= XEXP (DECL_RTL (fndecl
), 0);
2543 /* Generate an rtx (probably a pseudo-register) for the address. */
2546 funexp
= expand_normal (addr
);
2547 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
2552 /* Return the static chain for this function, if any. */
2555 rtx_for_static_chain (const_tree fndecl_or_type
, bool incoming_p
)
2557 if (DECL_P (fndecl_or_type
) && !DECL_STATIC_CHAIN (fndecl_or_type
))
2560 return targetm
.calls
.static_chain (fndecl_or_type
, incoming_p
);
2563 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
2566 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
2567 or NULL_RTX if none has been scanned yet. */
2568 rtx_insn
*scan_start
;
2569 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
2570 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
2571 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
2572 with fixed offset, or PC if this is with variable or unknown offset. */
2574 } internal_arg_pointer_exp_state
;
2576 static rtx
internal_arg_pointer_based_exp (const_rtx
, bool);
2578 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
2579 the tail call sequence, starting with first insn that hasn't been
2580 scanned yet, and note for each pseudo on the LHS whether it is based
2581 on crtl->args.internal_arg_pointer or not, and what offset from that
2582 that pointer it has. */
2585 internal_arg_pointer_based_exp_scan (void)
2587 rtx_insn
*insn
, *scan_start
= internal_arg_pointer_exp_state
.scan_start
;
2589 if (scan_start
== NULL_RTX
)
2590 insn
= get_insns ();
2592 insn
= NEXT_INSN (scan_start
);
2596 rtx set
= single_set (insn
);
2597 if (set
&& REG_P (SET_DEST (set
)) && !HARD_REGISTER_P (SET_DEST (set
)))
2600 unsigned int idx
= REGNO (SET_DEST (set
)) - FIRST_PSEUDO_REGISTER
;
2601 /* Punt on pseudos set multiple times. */
2602 if (idx
< internal_arg_pointer_exp_state
.cache
.length ()
2603 && (internal_arg_pointer_exp_state
.cache
[idx
]
2607 val
= internal_arg_pointer_based_exp (SET_SRC (set
), false);
2608 if (val
!= NULL_RTX
)
2610 if (idx
>= internal_arg_pointer_exp_state
.cache
.length ())
2611 internal_arg_pointer_exp_state
.cache
2612 .safe_grow_cleared (idx
+ 1);
2613 internal_arg_pointer_exp_state
.cache
[idx
] = val
;
2616 if (NEXT_INSN (insn
) == NULL_RTX
)
2618 insn
= NEXT_INSN (insn
);
2621 internal_arg_pointer_exp_state
.scan_start
= scan_start
;
2624 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
2625 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
2626 it with fixed offset, or PC if this is with variable or unknown offset.
2627 TOPLEVEL is true if the function is invoked at the topmost level. */
2630 internal_arg_pointer_based_exp (const_rtx rtl
, bool toplevel
)
2632 if (CONSTANT_P (rtl
))
2635 if (rtl
== crtl
->args
.internal_arg_pointer
)
2638 if (REG_P (rtl
) && HARD_REGISTER_P (rtl
))
2642 if (GET_CODE (rtl
) == PLUS
&& poly_int_rtx_p (XEXP (rtl
, 1), &offset
))
2644 rtx val
= internal_arg_pointer_based_exp (XEXP (rtl
, 0), toplevel
);
2645 if (val
== NULL_RTX
|| val
== pc_rtx
)
2647 return plus_constant (Pmode
, val
, offset
);
2650 /* When called at the topmost level, scan pseudo assignments in between the
2651 last scanned instruction in the tail call sequence and the latest insn
2652 in that sequence. */
2654 internal_arg_pointer_based_exp_scan ();
2658 unsigned int idx
= REGNO (rtl
) - FIRST_PSEUDO_REGISTER
;
2659 if (idx
< internal_arg_pointer_exp_state
.cache
.length ())
2660 return internal_arg_pointer_exp_state
.cache
[idx
];
2665 subrtx_iterator::array_type array
;
2666 FOR_EACH_SUBRTX (iter
, array
, rtl
, NONCONST
)
2668 const_rtx x
= *iter
;
2669 if (REG_P (x
) && internal_arg_pointer_based_exp (x
, false) != NULL_RTX
)
2672 iter
.skip_subrtxes ();
2678 /* Return true if SIZE bytes starting from address ADDR might overlap an
2679 already-clobbered argument area. This function is used to determine
2680 if we should give up a sibcall. */
2683 mem_might_overlap_already_clobbered_arg_p (rtx addr
, poly_uint64 size
)
2686 unsigned HOST_WIDE_INT start
, end
;
2689 if (bitmap_empty_p (stored_args_map
)
2690 && stored_args_watermark
== HOST_WIDE_INT_M1U
)
2692 val
= internal_arg_pointer_based_exp (addr
, true);
2693 if (val
== NULL_RTX
)
2695 else if (!poly_int_rtx_p (val
, &i
))
2698 if (known_eq (size
, 0U))
2701 if (STACK_GROWS_DOWNWARD
)
2702 i
-= crtl
->args
.pretend_args_size
;
2704 i
+= crtl
->args
.pretend_args_size
;
2706 if (ARGS_GROW_DOWNWARD
)
2709 /* We can ignore any references to the function's pretend args,
2710 which at this point would manifest as negative values of I. */
2711 if (known_le (i
, 0) && known_le (size
, poly_uint64 (-i
)))
2714 start
= maybe_lt (i
, 0) ? 0 : constant_lower_bound (i
);
2715 if (!(i
+ size
).is_constant (&end
))
2716 end
= HOST_WIDE_INT_M1U
;
2718 if (end
> stored_args_watermark
)
2721 end
= MIN (end
, SBITMAP_SIZE (stored_args_map
));
2722 for (unsigned HOST_WIDE_INT k
= start
; k
< end
; ++k
)
2723 if (bitmap_bit_p (stored_args_map
, k
))
2729 /* Do the register loads required for any wholly-register parms or any
2730 parms which are passed both on the stack and in a register. Their
2731 expressions were already evaluated.
2733 Mark all register-parms as living through the call, putting these USE
2734 insns in the CALL_INSN_FUNCTION_USAGE field.
2736 When IS_SIBCALL, perform the check_sibcall_argument_overlap
2737 checking, setting *SIBCALL_FAILURE if appropriate. */
2740 load_register_parameters (struct arg_data
*args
, int num_actuals
,
2741 rtx
*call_fusage
, int flags
, int is_sibcall
,
2742 int *sibcall_failure
)
2746 for (i
= 0; i
< num_actuals
; i
++)
2748 rtx reg
= ((flags
& ECF_SIBCALL
)
2749 ? args
[i
].tail_call_reg
: args
[i
].reg
);
2752 int partial
= args
[i
].partial
;
2754 poly_int64 size
= 0;
2755 HOST_WIDE_INT const_size
= 0;
2756 rtx_insn
*before_arg
= get_last_insn ();
2757 /* Set non-negative if we must move a word at a time, even if
2758 just one word (e.g, partial == 4 && mode == DFmode). Set
2759 to -1 if we just use a normal move insn. This value can be
2760 zero if the argument is a zero size structure. */
2762 if (GET_CODE (reg
) == PARALLEL
)
2766 gcc_assert (partial
% UNITS_PER_WORD
== 0);
2767 nregs
= partial
/ UNITS_PER_WORD
;
2769 else if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
)
2771 /* Variable-sized parameters should be described by a
2772 PARALLEL instead. */
2773 const_size
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
2774 gcc_assert (const_size
>= 0);
2775 nregs
= (const_size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
2779 size
= GET_MODE_SIZE (args
[i
].mode
);
2781 /* Handle calls that pass values in multiple non-contiguous
2782 locations. The Irix 6 ABI has examples of this. */
2784 if (GET_CODE (reg
) == PARALLEL
)
2785 emit_group_move (reg
, args
[i
].parallel_value
);
2787 /* If simple case, just do move. If normal partial, store_one_arg
2788 has already loaded the register for us. In all other cases,
2789 load the register(s) from memory. */
2791 else if (nregs
== -1)
2793 emit_move_insn (reg
, args
[i
].value
);
2794 #ifdef BLOCK_REG_PADDING
2795 /* Handle case where we have a value that needs shifting
2796 up to the msb. eg. a QImode value and we're padding
2797 upward on a BYTES_BIG_ENDIAN machine. */
2798 if (args
[i
].locate
.where_pad
2799 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
))
2801 gcc_checking_assert (ordered_p (size
, UNITS_PER_WORD
));
2802 if (maybe_lt (size
, UNITS_PER_WORD
))
2806 = (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2808 /* Assigning REG here rather than a temp makes
2809 CALL_FUSAGE report the whole reg as used.
2810 Strictly speaking, the call only uses SIZE
2811 bytes at the msb end, but it doesn't seem worth
2812 generating rtl to say that. */
2813 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
2814 x
= expand_shift (LSHIFT_EXPR
, word_mode
,
2815 reg
, shift
, reg
, 1);
2817 emit_move_insn (reg
, x
);
2823 /* If we have pre-computed the values to put in the registers in
2824 the case of non-aligned structures, copy them in now. */
2826 else if (args
[i
].n_aligned_regs
!= 0)
2827 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
2828 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
2829 args
[i
].aligned_regs
[j
]);
2831 else if (partial
== 0 || args
[i
].pass_on_stack
)
2833 /* SIZE and CONST_SIZE are 0 for partial arguments and
2834 the size of a BLKmode type otherwise. */
2835 gcc_checking_assert (known_eq (size
, const_size
));
2836 rtx mem
= validize_mem (copy_rtx (args
[i
].value
));
2838 /* Check for overlap with already clobbered argument area,
2839 providing that this has non-zero size. */
2842 && (mem_might_overlap_already_clobbered_arg_p
2843 (XEXP (args
[i
].value
, 0), const_size
)))
2844 *sibcall_failure
= 1;
2846 if (const_size
% UNITS_PER_WORD
== 0
2847 || MEM_ALIGN (mem
) % BITS_PER_WORD
== 0)
2848 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
2852 move_block_to_reg (REGNO (reg
), mem
, nregs
- 1,
2854 rtx dest
= gen_rtx_REG (word_mode
, REGNO (reg
) + nregs
- 1);
2855 unsigned int bitoff
= (nregs
- 1) * BITS_PER_WORD
;
2856 unsigned int bitsize
= const_size
* BITS_PER_UNIT
- bitoff
;
2857 rtx x
= extract_bit_field (mem
, bitsize
, bitoff
, 1, dest
,
2858 word_mode
, word_mode
, false,
2860 if (BYTES_BIG_ENDIAN
)
2861 x
= expand_shift (LSHIFT_EXPR
, word_mode
, x
,
2862 BITS_PER_WORD
- bitsize
, dest
, 1);
2864 emit_move_insn (dest
, x
);
2867 /* Handle a BLKmode that needs shifting. */
2868 if (nregs
== 1 && const_size
< UNITS_PER_WORD
2869 #ifdef BLOCK_REG_PADDING
2870 && args
[i
].locate
.where_pad
== PAD_DOWNWARD
2876 rtx dest
= gen_rtx_REG (word_mode
, REGNO (reg
));
2877 int shift
= (UNITS_PER_WORD
- const_size
) * BITS_PER_UNIT
;
2878 enum tree_code dir
= (BYTES_BIG_ENDIAN
2879 ? RSHIFT_EXPR
: LSHIFT_EXPR
);
2882 x
= expand_shift (dir
, word_mode
, dest
, shift
, dest
, 1);
2884 emit_move_insn (dest
, x
);
2888 /* When a parameter is a block, and perhaps in other cases, it is
2889 possible that it did a load from an argument slot that was
2890 already clobbered. */
2892 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
2893 *sibcall_failure
= 1;
2895 /* Handle calls that pass values in multiple non-contiguous
2896 locations. The Irix 6 ABI has examples of this. */
2897 if (GET_CODE (reg
) == PARALLEL
)
2898 use_group_regs (call_fusage
, reg
);
2899 else if (nregs
== -1)
2900 use_reg_mode (call_fusage
, reg
,
2901 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)));
2903 use_regs (call_fusage
, REGNO (reg
), nregs
);
2908 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2909 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2910 bytes, then we would need to push some additional bytes to pad the
2911 arguments. So, we try to compute an adjust to the stack pointer for an
2912 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2913 bytes. Then, when the arguments are pushed the stack will be perfectly
2916 Return true if this optimization is possible, storing the adjustment
2917 in ADJUSTMENT_OUT and setting ARGS_SIZE->CONSTANT to the number of
2918 bytes that should be popped after the call. */
2921 combine_pending_stack_adjustment_and_call (poly_int64_pod
*adjustment_out
,
2922 poly_int64 unadjusted_args_size
,
2923 struct args_size
*args_size
,
2924 unsigned int preferred_unit_stack_boundary
)
2926 /* The number of bytes to pop so that the stack will be
2927 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2928 poly_int64 adjustment
;
2929 /* The alignment of the stack after the arguments are pushed, if we
2930 just pushed the arguments without adjust the stack here. */
2931 unsigned HOST_WIDE_INT unadjusted_alignment
;
2933 if (!known_misalignment (stack_pointer_delta
+ unadjusted_args_size
,
2934 preferred_unit_stack_boundary
,
2935 &unadjusted_alignment
))
2938 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2939 as possible -- leaving just enough left to cancel out the
2940 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2941 PENDING_STACK_ADJUST is non-negative, and congruent to
2942 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2944 /* Begin by trying to pop all the bytes. */
2945 unsigned HOST_WIDE_INT tmp_misalignment
;
2946 if (!known_misalignment (pending_stack_adjust
,
2947 preferred_unit_stack_boundary
,
2950 unadjusted_alignment
-= tmp_misalignment
;
2951 adjustment
= pending_stack_adjust
;
2952 /* Push enough additional bytes that the stack will be aligned
2953 after the arguments are pushed. */
2954 if (preferred_unit_stack_boundary
> 1 && unadjusted_alignment
)
2955 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
2957 /* We need to know whether the adjusted argument size
2958 (UNADJUSTED_ARGS_SIZE - ADJUSTMENT) constitutes an allocation
2959 or a deallocation. */
2960 if (!ordered_p (adjustment
, unadjusted_args_size
))
2963 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2964 bytes after the call. The right number is the entire
2965 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2966 by the arguments in the first place. */
2968 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
2970 *adjustment_out
= adjustment
;
2974 /* Scan X expression if it does not dereference any argument slots
2975 we already clobbered by tail call arguments (as noted in stored_args_map
2977 Return nonzero if X expression dereferences such argument slots,
2981 check_sibcall_argument_overlap_1 (rtx x
)
2990 code
= GET_CODE (x
);
2992 /* We need not check the operands of the CALL expression itself. */
2997 return (mem_might_overlap_already_clobbered_arg_p
2998 (XEXP (x
, 0), GET_MODE_SIZE (GET_MODE (x
))));
3000 /* Scan all subexpressions. */
3001 fmt
= GET_RTX_FORMAT (code
);
3002 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
3006 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
3009 else if (*fmt
== 'E')
3011 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
3012 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
3019 /* Scan sequence after INSN if it does not dereference any argument slots
3020 we already clobbered by tail call arguments (as noted in stored_args_map
3021 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
3022 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
3023 should be 0). Return nonzero if sequence after INSN dereferences such argument
3024 slots, zero otherwise. */
3027 check_sibcall_argument_overlap (rtx_insn
*insn
, struct arg_data
*arg
,
3028 int mark_stored_args_map
)
3030 poly_uint64 low
, high
;
3031 unsigned HOST_WIDE_INT const_low
, const_high
;
3033 if (insn
== NULL_RTX
)
3034 insn
= get_insns ();
3036 insn
= NEXT_INSN (insn
);
3038 for (; insn
; insn
= NEXT_INSN (insn
))
3040 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
3043 if (mark_stored_args_map
)
3045 if (ARGS_GROW_DOWNWARD
)
3046 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
3048 low
= arg
->locate
.slot_offset
.constant
;
3049 high
= low
+ arg
->locate
.size
.constant
;
3051 const_low
= constant_lower_bound (low
);
3052 if (high
.is_constant (&const_high
))
3053 for (unsigned HOST_WIDE_INT i
= const_low
; i
< const_high
; ++i
)
3054 bitmap_set_bit (stored_args_map
, i
);
3056 stored_args_watermark
= MIN (stored_args_watermark
, const_low
);
3058 return insn
!= NULL_RTX
;
3061 /* Given that a function returns a value of mode MODE at the most
3062 significant end of hard register VALUE, shift VALUE left or right
3063 as specified by LEFT_P. Return true if some action was needed. */
3066 shift_return_value (machine_mode mode
, bool left_p
, rtx value
)
3068 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
3069 machine_mode value_mode
= GET_MODE (value
);
3070 poly_int64 shift
= GET_MODE_BITSIZE (value_mode
) - GET_MODE_BITSIZE (mode
);
3072 if (known_eq (shift
, 0))
3075 /* Use ashr rather than lshr for right shifts. This is for the benefit
3076 of the MIPS port, which requires SImode values to be sign-extended
3077 when stored in 64-bit registers. */
3078 if (!force_expand_binop (value_mode
, left_p
? ashl_optab
: ashr_optab
,
3079 value
, gen_int_shift_amount (value_mode
, shift
),
3080 value
, 1, OPTAB_WIDEN
))
3085 /* If X is a likely-spilled register value, copy it to a pseudo
3086 register and return that register. Return X otherwise. */
3089 avoid_likely_spilled_reg (rtx x
)
3094 && HARD_REGISTER_P (x
)
3095 && targetm
.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x
))))
3097 /* Make sure that we generate a REG rather than a CONCAT.
3098 Moves into CONCATs can need nontrivial instructions,
3099 and the whole point of this function is to avoid
3100 using the hard register directly in such a situation. */
3101 generating_concat_p
= 0;
3102 new_rtx
= gen_reg_rtx (GET_MODE (x
));
3103 generating_concat_p
= 1;
3104 emit_move_insn (new_rtx
, x
);
3110 /* Helper function for expand_call.
3111 Return false is EXP is not implementable as a sibling call. */
3114 can_implement_as_sibling_call_p (tree exp
,
3115 rtx structure_value_addr
,
3117 int reg_parm_stack_space ATTRIBUTE_UNUSED
,
3121 const args_size
&args_size
)
3123 if (!targetm
.have_sibcall_epilogue ())
3125 maybe_complain_about_tail_call
3127 "machine description does not have"
3128 " a sibcall_epilogue instruction pattern");
3132 /* Doing sibling call optimization needs some work, since
3133 structure_value_addr can be allocated on the stack.
3134 It does not seem worth the effort since few optimizable
3135 sibling calls will return a structure. */
3136 if (structure_value_addr
!= NULL_RTX
)
3138 maybe_complain_about_tail_call (exp
, "callee returns a structure");
3142 #ifdef REG_PARM_STACK_SPACE
3143 /* If outgoing reg parm stack space changes, we cannot do sibcall. */
3144 if (OUTGOING_REG_PARM_STACK_SPACE (funtype
)
3145 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl
))
3146 || (reg_parm_stack_space
!= REG_PARM_STACK_SPACE (current_function_decl
)))
3148 maybe_complain_about_tail_call (exp
,
3149 "inconsistent size of stack space"
3150 " allocated for arguments which are"
3151 " passed in registers");
3156 /* Check whether the target is able to optimize the call
3158 if (!targetm
.function_ok_for_sibcall (fndecl
, exp
))
3160 maybe_complain_about_tail_call (exp
,
3161 "target is not able to optimize the"
3162 " call into a sibling call");
3166 /* Functions that do not return exactly once may not be sibcall
3168 if (flags
& ECF_RETURNS_TWICE
)
3170 maybe_complain_about_tail_call (exp
, "callee returns twice");
3173 if (flags
& ECF_NORETURN
)
3175 maybe_complain_about_tail_call (exp
, "callee does not return");
3179 if (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
))))
3181 maybe_complain_about_tail_call (exp
, "volatile function type");
3185 /* If the called function is nested in the current one, it might access
3186 some of the caller's arguments, but could clobber them beforehand if
3187 the argument areas are shared. */
3188 if (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
3190 maybe_complain_about_tail_call (exp
, "nested function");
3194 /* If this function requires more stack slots than the current
3195 function, we cannot change it into a sibling call.
3196 crtl->args.pretend_args_size is not part of the
3197 stack allocated by our caller. */
3198 if (maybe_gt (args_size
.constant
,
3199 crtl
->args
.size
- crtl
->args
.pretend_args_size
))
3201 maybe_complain_about_tail_call (exp
,
3202 "callee required more stack slots"
3203 " than the caller");
3207 /* If the callee pops its own arguments, then it must pop exactly
3208 the same number of arguments as the current function. */
3209 if (maybe_ne (targetm
.calls
.return_pops_args (fndecl
, funtype
,
3210 args_size
.constant
),
3211 targetm
.calls
.return_pops_args (current_function_decl
,
3213 (current_function_decl
),
3216 maybe_complain_about_tail_call (exp
,
3217 "inconsistent number of"
3218 " popped arguments");
3222 if (!lang_hooks
.decls
.ok_for_sibcall (fndecl
))
3224 maybe_complain_about_tail_call (exp
, "frontend does not support"
3229 /* All checks passed. */
3233 /* Update stack alignment when the parameter is passed in the stack
3234 since the outgoing parameter requires extra alignment on the calling
3238 update_stack_alignment_for_call (struct locate_and_pad_arg_data
*locate
)
3240 if (crtl
->stack_alignment_needed
< locate
->boundary
)
3241 crtl
->stack_alignment_needed
= locate
->boundary
;
3242 if (crtl
->preferred_stack_boundary
< locate
->boundary
)
3243 crtl
->preferred_stack_boundary
= locate
->boundary
;
3246 /* Generate all the code for a CALL_EXPR exp
3247 and return an rtx for its value.
3248 Store the value in TARGET (specified as an rtx) if convenient.
3249 If the value is stored in TARGET then TARGET is returned.
3250 If IGNORE is nonzero, then we ignore the value of the function call. */
3253 expand_call (tree exp
, rtx target
, int ignore
)
3255 /* Nonzero if we are currently expanding a call. */
3256 static int currently_expanding_call
= 0;
3258 /* RTX for the function to be called. */
3260 /* Sequence of insns to perform a normal "call". */
3261 rtx_insn
*normal_call_insns
= NULL
;
3262 /* Sequence of insns to perform a tail "call". */
3263 rtx_insn
*tail_call_insns
= NULL
;
3264 /* Data type of the function. */
3266 tree type_arg_types
;
3268 /* Declaration of the function being called,
3269 or 0 if the function is computed (not known by name). */
3271 /* The type of the function being called. */
3273 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
3274 bool must_tail_call
= CALL_EXPR_MUST_TAIL_CALL (exp
);
3277 /* Register in which non-BLKmode value will be returned,
3278 or 0 if no value or if value is BLKmode. */
3280 /* Address where we should return a BLKmode value;
3281 0 if value not BLKmode. */
3282 rtx structure_value_addr
= 0;
3283 /* Nonzero if that address is being passed by treating it as
3284 an extra, implicit first parameter. Otherwise,
3285 it is passed by being copied directly into struct_value_rtx. */
3286 int structure_value_addr_parm
= 0;
3287 /* Holds the value of implicit argument for the struct value. */
3288 tree structure_value_addr_value
= NULL_TREE
;
3289 /* Size of aggregate value wanted, or zero if none wanted
3290 or if we are using the non-reentrant PCC calling convention
3291 or expecting the value in registers. */
3292 poly_int64 struct_value_size
= 0;
3293 /* Nonzero if called function returns an aggregate in memory PCC style,
3294 by returning the address of where to find it. */
3295 int pcc_struct_value
= 0;
3296 rtx struct_value
= 0;
3298 /* Number of actual parameters in this call, including struct value addr. */
3300 /* Number of named args. Args after this are anonymous ones
3301 and they must all go on the stack. */
3303 /* Number of complex actual arguments that need to be split. */
3304 int num_complex_actuals
= 0;
3306 /* Vector of information about each argument.
3307 Arguments are numbered in the order they will be pushed,
3308 not the order they are written. */
3309 struct arg_data
*args
;
3311 /* Total size in bytes of all the stack-parms scanned so far. */
3312 struct args_size args_size
;
3313 struct args_size adjusted_args_size
;
3314 /* Size of arguments before any adjustments (such as rounding). */
3315 poly_int64 unadjusted_args_size
;
3316 /* Data on reg parms scanned so far. */
3317 CUMULATIVE_ARGS args_so_far_v
;
3318 cumulative_args_t args_so_far
;
3319 /* Nonzero if a reg parm has been scanned. */
3321 /* Nonzero if this is an indirect function call. */
3323 /* Nonzero if we must avoid push-insns in the args for this call.
3324 If stack space is allocated for register parameters, but not by the
3325 caller, then it is preallocated in the fixed part of the stack frame.
3326 So the entire argument block must then be preallocated (i.e., we
3327 ignore PUSH_ROUNDING in that case). */
3329 int must_preallocate
= !PUSH_ARGS
;
3331 /* Size of the stack reserved for parameter registers. */
3332 int reg_parm_stack_space
= 0;
3334 /* Address of space preallocated for stack parms
3335 (on machines that lack push insns), or 0 if space not preallocated. */
3338 /* Mask of ECF_ and ERF_ flags. */
3340 int return_flags
= 0;
3341 #ifdef REG_PARM_STACK_SPACE
3342 /* Define the boundary of the register parm stack space that needs to be
3344 int low_to_save
, high_to_save
;
3345 rtx save_area
= 0; /* Place that it is saved */
3348 unsigned int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3349 char *initial_stack_usage_map
= stack_usage_map
;
3350 unsigned HOST_WIDE_INT initial_stack_usage_watermark
= stack_usage_watermark
;
3351 char *stack_usage_map_buf
= NULL
;
3353 poly_int64 old_stack_allocated
;
3355 /* State variables to track stack modifications. */
3356 rtx old_stack_level
= 0;
3357 int old_stack_arg_under_construction
= 0;
3358 poly_int64 old_pending_adj
= 0;
3359 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3361 /* Some stack pointer alterations we make are performed via
3362 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
3363 which we then also need to save/restore along the way. */
3364 poly_int64 old_stack_pointer_delta
= 0;
3367 tree addr
= CALL_EXPR_FN (exp
);
3369 /* The alignment of the stack, in bits. */
3370 unsigned HOST_WIDE_INT preferred_stack_boundary
;
3371 /* The alignment of the stack, in bytes. */
3372 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
3373 /* The static chain value to use for this call. */
3374 rtx static_chain_value
;
3375 /* See if this is "nothrow" function call. */
3376 if (TREE_NOTHROW (exp
))
3377 flags
|= ECF_NOTHROW
;
3379 /* See if we can find a DECL-node for the actual function, and get the
3380 function attributes (flags) from the function decl or type node. */
3381 fndecl
= get_callee_fndecl (exp
);
3384 fntype
= TREE_TYPE (fndecl
);
3385 flags
|= flags_from_decl_or_type (fndecl
);
3386 return_flags
|= decl_return_flags (fndecl
);
3390 fntype
= TREE_TYPE (TREE_TYPE (addr
));
3391 flags
|= flags_from_decl_or_type (fntype
);
3392 if (CALL_EXPR_BY_DESCRIPTOR (exp
))
3393 flags
|= ECF_BY_DESCRIPTOR
;
3395 rettype
= TREE_TYPE (exp
);
3397 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
3399 /* Warn if this value is an aggregate type,
3400 regardless of which calling convention we are using for it. */
3401 if (AGGREGATE_TYPE_P (rettype
))
3402 warning (OPT_Waggregate_return
, "function call has aggregate value");
3404 /* If the result of a non looping pure or const function call is
3405 ignored (or void), and none of its arguments are volatile, we can
3406 avoid expanding the call and just evaluate the arguments for
3408 if ((flags
& (ECF_CONST
| ECF_PURE
))
3409 && (!(flags
& ECF_LOOPING_CONST_OR_PURE
))
3410 && (ignore
|| target
== const0_rtx
3411 || TYPE_MODE (rettype
) == VOIDmode
))
3413 bool volatilep
= false;
3415 call_expr_arg_iterator iter
;
3417 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3418 if (TREE_THIS_VOLATILE (arg
))
3426 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3427 expand_expr (arg
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
3432 #ifdef REG_PARM_STACK_SPACE
3433 reg_parm_stack_space
= REG_PARM_STACK_SPACE (!fndecl
? fntype
: fndecl
);
3436 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
3437 && reg_parm_stack_space
> 0 && PUSH_ARGS
)
3438 must_preallocate
= 1;
3440 /* Set up a place to return a structure. */
3442 /* Cater to broken compilers. */
3443 if (aggregate_value_p (exp
, fntype
))
3445 /* This call returns a big structure. */
3446 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
3448 #ifdef PCC_STATIC_STRUCT_RETURN
3450 pcc_struct_value
= 1;
3452 #else /* not PCC_STATIC_STRUCT_RETURN */
3454 if (!poly_int_tree_p (TYPE_SIZE_UNIT (rettype
), &struct_value_size
))
3455 struct_value_size
= -1;
3457 /* Even if it is semantically safe to use the target as the return
3458 slot, it may be not sufficiently aligned for the return type. */
3459 if (CALL_EXPR_RETURN_SLOT_OPT (exp
)
3462 /* If rettype is addressable, we may not create a temporary.
3463 If target is properly aligned at runtime and the compiler
3464 just doesn't know about it, it will work fine, otherwise it
3466 && (TREE_ADDRESSABLE (rettype
)
3467 || !(MEM_ALIGN (target
) < TYPE_ALIGN (rettype
)
3468 && targetm
.slow_unaligned_access (TYPE_MODE (rettype
),
3469 MEM_ALIGN (target
)))))
3470 structure_value_addr
= XEXP (target
, 0);
3473 /* For variable-sized objects, we must be called with a target
3474 specified. If we were to allocate space on the stack here,
3475 we would have no way of knowing when to free it. */
3476 rtx d
= assign_temp (rettype
, 1, 1);
3477 structure_value_addr
= XEXP (d
, 0);
3481 #endif /* not PCC_STATIC_STRUCT_RETURN */
3484 /* Figure out the amount to which the stack should be aligned. */
3485 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3488 struct cgraph_rtl_info
*i
= cgraph_node::rtl_info (fndecl
);
3489 /* Without automatic stack alignment, we can't increase preferred
3490 stack boundary. With automatic stack alignment, it is
3491 unnecessary since unless we can guarantee that all callers will
3492 align the outgoing stack properly, callee has to align its
3495 && i
->preferred_incoming_stack_boundary
3496 && i
->preferred_incoming_stack_boundary
< preferred_stack_boundary
)
3497 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
3500 /* Operand 0 is a pointer-to-function; get the type of the function. */
3501 funtype
= TREE_TYPE (addr
);
3502 gcc_assert (POINTER_TYPE_P (funtype
));
3503 funtype
= TREE_TYPE (funtype
);
3505 /* Count whether there are actual complex arguments that need to be split
3506 into their real and imaginary parts. Munge the type_arg_types
3507 appropriately here as well. */
3508 if (targetm
.calls
.split_complex_arg
)
3510 call_expr_arg_iterator iter
;
3512 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3514 tree type
= TREE_TYPE (arg
);
3515 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
3516 && targetm
.calls
.split_complex_arg (type
))
3517 num_complex_actuals
++;
3519 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
3522 type_arg_types
= TYPE_ARG_TYPES (funtype
);
3524 if (flags
& ECF_MAY_BE_ALLOCA
)
3525 cfun
->calls_alloca
= 1;
3527 /* If struct_value_rtx is 0, it means pass the address
3528 as if it were an extra parameter. Put the argument expression
3529 in structure_value_addr_value. */
3530 if (structure_value_addr
&& struct_value
== 0)
3532 /* If structure_value_addr is a REG other than
3533 virtual_outgoing_args_rtx, we can use always use it. If it
3534 is not a REG, we must always copy it into a register.
3535 If it is virtual_outgoing_args_rtx, we must copy it to another
3536 register in some cases. */
3537 rtx temp
= (!REG_P (structure_value_addr
)
3538 || (ACCUMULATE_OUTGOING_ARGS
3539 && stack_arg_under_construction
3540 && structure_value_addr
== virtual_outgoing_args_rtx
)
3541 ? copy_addr_to_reg (convert_memory_address
3542 (Pmode
, structure_value_addr
))
3543 : structure_value_addr
);
3545 structure_value_addr_value
=
3546 make_tree (build_pointer_type (TREE_TYPE (funtype
)), temp
);
3547 structure_value_addr_parm
= 1;
3550 /* Count the arguments and set NUM_ACTUALS. */
3552 call_expr_nargs (exp
) + num_complex_actuals
+ structure_value_addr_parm
;
3554 /* Compute number of named args.
3555 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
3557 if (type_arg_types
!= 0)
3559 = (list_length (type_arg_types
)
3560 /* Count the struct value address, if it is passed as a parm. */
3561 + structure_value_addr_parm
);
3563 /* If we know nothing, treat all args as named. */
3564 n_named_args
= num_actuals
;
3566 /* Start updating where the next arg would go.
3568 On some machines (such as the PA) indirect calls have a different
3569 calling convention than normal calls. The fourth argument in
3570 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
3572 INIT_CUMULATIVE_ARGS (args_so_far_v
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
3573 args_so_far
= pack_cumulative_args (&args_so_far_v
);
3575 /* Now possibly adjust the number of named args.
3576 Normally, don't include the last named arg if anonymous args follow.
3577 We do include the last named arg if
3578 targetm.calls.strict_argument_naming() returns nonzero.
3579 (If no anonymous args follow, the result of list_length is actually
3580 one too large. This is harmless.)
3582 If targetm.calls.pretend_outgoing_varargs_named() returns
3583 nonzero, and targetm.calls.strict_argument_naming() returns zero,
3584 this machine will be able to place unnamed args that were passed
3585 in registers into the stack. So treat all args as named. This
3586 allows the insns emitting for a specific argument list to be
3587 independent of the function declaration.
3589 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
3590 we do not have any reliable way to pass unnamed args in
3591 registers, so we must force them into memory. */
3593 if (type_arg_types
!= 0
3594 && targetm
.calls
.strict_argument_naming (args_so_far
))
3596 else if (type_arg_types
!= 0
3597 && ! targetm
.calls
.pretend_outgoing_varargs_named (args_so_far
))
3598 /* Don't include the last named arg. */
3601 /* Treat all args as named. */
3602 n_named_args
= num_actuals
;
3604 /* Make a vector to hold all the information about each arg. */
3605 args
= XCNEWVEC (struct arg_data
, num_actuals
);
3607 /* Build up entries in the ARGS array, compute the size of the
3608 arguments into ARGS_SIZE, etc. */
3609 initialize_argument_information (num_actuals
, args
, &args_size
,
3611 structure_value_addr_value
, fndecl
, fntype
,
3612 args_so_far
, reg_parm_stack_space
,
3613 &old_stack_level
, &old_pending_adj
,
3614 &must_preallocate
, &flags
,
3615 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
3618 must_preallocate
= 1;
3620 /* Now make final decision about preallocating stack space. */
3621 must_preallocate
= finalize_must_preallocate (must_preallocate
,
3625 /* If the structure value address will reference the stack pointer, we
3626 must stabilize it. We don't need to do this if we know that we are
3627 not going to adjust the stack pointer in processing this call. */
3629 if (structure_value_addr
3630 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
3631 || reg_mentioned_p (virtual_outgoing_args_rtx
,
3632 structure_value_addr
))
3634 || (!ACCUMULATE_OUTGOING_ARGS
3635 && maybe_ne (args_size
.constant
, 0))))
3636 structure_value_addr
= copy_to_reg (structure_value_addr
);
3638 /* Tail calls can make things harder to debug, and we've traditionally
3639 pushed these optimizations into -O2. Don't try if we're already
3640 expanding a call, as that means we're an argument. Don't try if
3641 there's cleanups, as we know there's code to follow the call. */
3642 if (currently_expanding_call
++ != 0
3643 || (!flag_optimize_sibling_calls
&& !CALL_FROM_THUNK_P (exp
))
3645 || dbg_cnt (tail_call
) == false)
3648 /* Workaround buggy C/C++ wrappers around Fortran routines with
3649 character(len=constant) arguments if the hidden string length arguments
3650 are passed on the stack; if the callers forget to pass those arguments,
3651 attempting to tail call in such routines leads to stack corruption.
3652 Avoid tail calls in functions where at least one such hidden string
3653 length argument is passed (partially or fully) on the stack in the
3654 caller and the callee needs to pass any arguments on the stack.
3656 if (try_tail_call
&& maybe_ne (args_size
.constant
, 0))
3657 for (tree arg
= DECL_ARGUMENTS (current_function_decl
);
3658 arg
; arg
= DECL_CHAIN (arg
))
3659 if (DECL_HIDDEN_STRING_LENGTH (arg
) && DECL_INCOMING_RTL (arg
))
3661 subrtx_iterator::array_type array
;
3662 FOR_EACH_SUBRTX (iter
, array
, DECL_INCOMING_RTL (arg
), NONCONST
)
3670 /* If the user has marked the function as requiring tail-call
3671 optimization, attempt it. */
3675 /* Rest of purposes for tail call optimizations to fail. */
3677 try_tail_call
= can_implement_as_sibling_call_p (exp
,
3678 structure_value_addr
,
3680 reg_parm_stack_space
,
3682 flags
, addr
, args_size
);
3684 /* Check if caller and callee disagree in promotion of function
3688 machine_mode caller_mode
, caller_promoted_mode
;
3689 machine_mode callee_mode
, callee_promoted_mode
;
3690 int caller_unsignedp
, callee_unsignedp
;
3691 tree caller_res
= DECL_RESULT (current_function_decl
);
3693 caller_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (caller_res
));
3694 caller_mode
= DECL_MODE (caller_res
);
3695 callee_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (funtype
));
3696 callee_mode
= TYPE_MODE (TREE_TYPE (funtype
));
3697 caller_promoted_mode
3698 = promote_function_mode (TREE_TYPE (caller_res
), caller_mode
,
3700 TREE_TYPE (current_function_decl
), 1);
3701 callee_promoted_mode
3702 = promote_function_mode (TREE_TYPE (funtype
), callee_mode
,
3705 if (caller_mode
!= VOIDmode
3706 && (caller_promoted_mode
!= callee_promoted_mode
3707 || ((caller_mode
!= caller_promoted_mode
3708 || callee_mode
!= callee_promoted_mode
)
3709 && (caller_unsignedp
!= callee_unsignedp
3710 || partial_subreg_p (caller_mode
, callee_mode
)))))
3713 maybe_complain_about_tail_call (exp
,
3714 "caller and callee disagree in"
3715 " promotion of function"
3720 /* Ensure current function's preferred stack boundary is at least
3721 what we need. Stack alignment may also increase preferred stack
3723 for (i
= 0; i
< num_actuals
; i
++)
3724 if (reg_parm_stack_space
> 0
3726 || args
[i
].partial
!= 0
3727 || args
[i
].pass_on_stack
)
3728 update_stack_alignment_for_call (&args
[i
].locate
);
3729 if (crtl
->preferred_stack_boundary
< preferred_stack_boundary
)
3730 crtl
->preferred_stack_boundary
= preferred_stack_boundary
;
3732 preferred_stack_boundary
= crtl
->preferred_stack_boundary
;
3734 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
3736 /* We want to make two insn chains; one for a sibling call, the other
3737 for a normal call. We will select one of the two chains after
3738 initial RTL generation is complete. */
3739 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
3741 int sibcall_failure
= 0;
3742 /* We want to emit any pending stack adjustments before the tail
3743 recursion "call". That way we know any adjustment after the tail
3744 recursion call can be ignored if we indeed use the tail
3746 saved_pending_stack_adjust save
;
3747 rtx_insn
*insns
, *before_call
, *after_args
;
3752 /* State variables we need to save and restore between
3754 save_pending_stack_adjust (&save
);
3757 flags
&= ~ECF_SIBCALL
;
3759 flags
|= ECF_SIBCALL
;
3761 /* Other state variables that we must reinitialize each time
3762 through the loop (that are not initialized by the loop itself). */
3766 /* Start a new sequence for the normal call case.
3768 From this point on, if the sibling call fails, we want to set
3769 sibcall_failure instead of continuing the loop. */
3772 /* Don't let pending stack adjusts add up to too much.
3773 Also, do all pending adjustments now if there is any chance
3774 this might be a call to alloca or if we are expanding a sibling
3776 Also do the adjustments before a throwing call, otherwise
3777 exception handling can fail; PR 19225. */
3778 if (maybe_ge (pending_stack_adjust
, 32)
3779 || (maybe_ne (pending_stack_adjust
, 0)
3780 && (flags
& ECF_MAY_BE_ALLOCA
))
3781 || (maybe_ne (pending_stack_adjust
, 0)
3782 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
3784 do_pending_stack_adjust ();
3786 /* Precompute any arguments as needed. */
3788 precompute_arguments (num_actuals
, args
);
3790 /* Now we are about to start emitting insns that can be deleted
3791 if a libcall is deleted. */
3792 if (pass
&& (flags
& ECF_MALLOC
))
3796 && crtl
->stack_protect_guard
3797 && targetm
.stack_protect_runtime_enabled_p ())
3798 stack_protect_epilogue ();
3800 adjusted_args_size
= args_size
;
3801 /* Compute the actual size of the argument block required. The variable
3802 and constant sizes must be combined, the size may have to be rounded,
3803 and there may be a minimum required size. When generating a sibcall
3804 pattern, do not round up, since we'll be re-using whatever space our
3806 unadjusted_args_size
3807 = compute_argument_block_size (reg_parm_stack_space
,
3808 &adjusted_args_size
,
3811 : preferred_stack_boundary
));
3813 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
3815 /* The argument block when performing a sibling call is the
3816 incoming argument block. */
3819 argblock
= crtl
->args
.internal_arg_pointer
;
3820 if (STACK_GROWS_DOWNWARD
)
3822 = plus_constant (Pmode
, argblock
, crtl
->args
.pretend_args_size
);
3825 = plus_constant (Pmode
, argblock
, -crtl
->args
.pretend_args_size
);
3827 HOST_WIDE_INT map_size
= constant_lower_bound (args_size
.constant
);
3828 stored_args_map
= sbitmap_alloc (map_size
);
3829 bitmap_clear (stored_args_map
);
3830 stored_args_watermark
= HOST_WIDE_INT_M1U
;
3833 /* If we have no actual push instructions, or shouldn't use them,
3834 make space for all args right now. */
3835 else if (adjusted_args_size
.var
!= 0)
3837 if (old_stack_level
== 0)
3839 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
3840 old_stack_pointer_delta
= stack_pointer_delta
;
3841 old_pending_adj
= pending_stack_adjust
;
3842 pending_stack_adjust
= 0;
3843 /* stack_arg_under_construction says whether a stack arg is
3844 being constructed at the old stack level. Pushing the stack
3845 gets a clean outgoing argument block. */
3846 old_stack_arg_under_construction
= stack_arg_under_construction
;
3847 stack_arg_under_construction
= 0;
3849 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
3850 if (flag_stack_usage_info
)
3851 current_function_has_unbounded_dynamic_stack_size
= 1;
3855 /* Note that we must go through the motions of allocating an argument
3856 block even if the size is zero because we may be storing args
3857 in the area reserved for register arguments, which may be part of
3860 poly_int64 needed
= adjusted_args_size
.constant
;
3862 /* Store the maximum argument space used. It will be pushed by
3863 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
3866 crtl
->outgoing_args_size
= upper_bound (crtl
->outgoing_args_size
,
3869 if (must_preallocate
)
3871 if (ACCUMULATE_OUTGOING_ARGS
)
3873 /* Since the stack pointer will never be pushed, it is
3874 possible for the evaluation of a parm to clobber
3875 something we have already written to the stack.
3876 Since most function calls on RISC machines do not use
3877 the stack, this is uncommon, but must work correctly.
3879 Therefore, we save any area of the stack that was already
3880 written and that we are using. Here we set up to do this
3881 by making a new stack usage map from the old one. The
3882 actual save will be done by store_one_arg.
3884 Another approach might be to try to reorder the argument
3885 evaluations to avoid this conflicting stack usage. */
3887 /* Since we will be writing into the entire argument area,
3888 the map must be allocated for its entire size, not just
3889 the part that is the responsibility of the caller. */
3890 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3891 needed
+= reg_parm_stack_space
;
3893 poly_int64 limit
= needed
;
3894 if (ARGS_GROW_DOWNWARD
)
3897 /* For polynomial sizes, this is the maximum possible
3898 size needed for arguments with a constant size
3900 HOST_WIDE_INT const_limit
= constant_lower_bound (limit
);
3901 highest_outgoing_arg_in_use
3902 = MAX (initial_highest_arg_in_use
, const_limit
);
3904 free (stack_usage_map_buf
);
3905 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
3906 stack_usage_map
= stack_usage_map_buf
;
3908 if (initial_highest_arg_in_use
)
3909 memcpy (stack_usage_map
, initial_stack_usage_map
,
3910 initial_highest_arg_in_use
);
3912 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3913 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3914 (highest_outgoing_arg_in_use
3915 - initial_highest_arg_in_use
));
3918 /* The address of the outgoing argument list must not be
3919 copied to a register here, because argblock would be left
3920 pointing to the wrong place after the call to
3921 allocate_dynamic_stack_space below. */
3923 argblock
= virtual_outgoing_args_rtx
;
3927 /* Try to reuse some or all of the pending_stack_adjust
3928 to get this space. */
3929 if (inhibit_defer_pop
== 0
3930 && (combine_pending_stack_adjustment_and_call
3932 unadjusted_args_size
,
3933 &adjusted_args_size
,
3934 preferred_unit_stack_boundary
)))
3936 /* combine_pending_stack_adjustment_and_call computes
3937 an adjustment before the arguments are allocated.
3938 Account for them and see whether or not the stack
3939 needs to go up or down. */
3940 needed
= unadjusted_args_size
- needed
;
3943 combine_pending_stack_adjustment_and_call. */
3944 gcc_checking_assert (ordered_p (needed
, 0));
3945 if (maybe_lt (needed
, 0))
3947 /* We're releasing stack space. */
3948 /* ??? We can avoid any adjustment at all if we're
3949 already aligned. FIXME. */
3950 pending_stack_adjust
= -needed
;
3951 do_pending_stack_adjust ();
3955 /* We need to allocate space. We'll do that in
3956 push_block below. */
3957 pending_stack_adjust
= 0;
3960 /* Special case this because overhead of `push_block' in
3961 this case is non-trivial. */
3962 if (known_eq (needed
, 0))
3963 argblock
= virtual_outgoing_args_rtx
;
3966 rtx needed_rtx
= gen_int_mode (needed
, Pmode
);
3967 argblock
= push_block (needed_rtx
, 0, 0);
3968 if (ARGS_GROW_DOWNWARD
)
3969 argblock
= plus_constant (Pmode
, argblock
, needed
);
3972 /* We only really need to call `copy_to_reg' in the case
3973 where push insns are going to be used to pass ARGBLOCK
3974 to a function call in ARGS. In that case, the stack
3975 pointer changes value from the allocation point to the
3976 call point, and hence the value of
3977 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3978 as well always do it. */
3979 argblock
= copy_to_reg (argblock
);
3984 if (ACCUMULATE_OUTGOING_ARGS
)
3986 /* The save/restore code in store_one_arg handles all
3987 cases except one: a constructor call (including a C
3988 function returning a BLKmode struct) to initialize
3990 if (stack_arg_under_construction
)
3994 (adjusted_args_size
.constant
3995 + (OUTGOING_REG_PARM_STACK_SPACE (!fndecl
? fntype
3996 : TREE_TYPE (fndecl
))
3997 ? 0 : reg_parm_stack_space
), Pmode
));
3998 if (old_stack_level
== 0)
4000 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
4001 old_stack_pointer_delta
= stack_pointer_delta
;
4002 old_pending_adj
= pending_stack_adjust
;
4003 pending_stack_adjust
= 0;
4004 /* stack_arg_under_construction says whether a stack
4005 arg is being constructed at the old stack level.
4006 Pushing the stack gets a clean outgoing argument
4008 old_stack_arg_under_construction
4009 = stack_arg_under_construction
;
4010 stack_arg_under_construction
= 0;
4011 /* Make a new map for the new argument list. */
4012 free (stack_usage_map_buf
);
4013 stack_usage_map_buf
= XCNEWVEC (char, highest_outgoing_arg_in_use
);
4014 stack_usage_map
= stack_usage_map_buf
;
4015 highest_outgoing_arg_in_use
= 0;
4016 stack_usage_watermark
= HOST_WIDE_INT_M1U
;
4018 /* We can pass TRUE as the 4th argument because we just
4019 saved the stack pointer and will restore it right after
4021 allocate_dynamic_stack_space (push_size
, 0, BIGGEST_ALIGNMENT
,
4025 /* If argument evaluation might modify the stack pointer,
4026 copy the address of the argument list to a register. */
4027 for (i
= 0; i
< num_actuals
; i
++)
4028 if (args
[i
].pass_on_stack
)
4030 argblock
= copy_addr_to_reg (argblock
);
4035 compute_argument_addresses (args
, argblock
, num_actuals
);
4037 /* Stack is properly aligned, pops can't safely be deferred during
4038 the evaluation of the arguments. */
4041 /* Precompute all register parameters. It isn't safe to compute
4042 anything once we have started filling any specific hard regs.
4043 TLS symbols sometimes need a call to resolve. Precompute
4044 register parameters before any stack pointer manipulation
4045 to avoid unaligned stack in the called function. */
4046 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
4050 /* Perform stack alignment before the first push (the last arg). */
4052 && maybe_gt (adjusted_args_size
.constant
, reg_parm_stack_space
)
4053 && maybe_ne (adjusted_args_size
.constant
, unadjusted_args_size
))
4055 /* When the stack adjustment is pending, we get better code
4056 by combining the adjustments. */
4057 if (maybe_ne (pending_stack_adjust
, 0)
4058 && ! inhibit_defer_pop
4059 && (combine_pending_stack_adjustment_and_call
4060 (&pending_stack_adjust
,
4061 unadjusted_args_size
,
4062 &adjusted_args_size
,
4063 preferred_unit_stack_boundary
)))
4064 do_pending_stack_adjust ();
4065 else if (argblock
== 0)
4066 anti_adjust_stack (gen_int_mode (adjusted_args_size
.constant
4067 - unadjusted_args_size
,
4070 /* Now that the stack is properly aligned, pops can't safely
4071 be deferred during the evaluation of the arguments. */
4074 /* Record the maximum pushed stack space size. We need to delay
4075 doing it this far to take into account the optimization done
4076 by combine_pending_stack_adjustment_and_call. */
4077 if (flag_stack_usage_info
4078 && !ACCUMULATE_OUTGOING_ARGS
4080 && adjusted_args_size
.var
== 0)
4082 poly_int64 pushed
= (adjusted_args_size
.constant
4083 + pending_stack_adjust
);
4084 current_function_pushed_stack_size
4085 = upper_bound (current_function_pushed_stack_size
, pushed
);
4088 funexp
= rtx_for_function_call (fndecl
, addr
);
4090 if (CALL_EXPR_STATIC_CHAIN (exp
))
4091 static_chain_value
= expand_normal (CALL_EXPR_STATIC_CHAIN (exp
));
4093 static_chain_value
= 0;
4095 #ifdef REG_PARM_STACK_SPACE
4096 /* Save the fixed argument area if it's part of the caller's frame and
4097 is clobbered by argument setup for this call. */
4098 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
4099 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
4100 &low_to_save
, &high_to_save
);
4103 /* Now store (and compute if necessary) all non-register parms.
4104 These come before register parms, since they can require block-moves,
4105 which could clobber the registers used for register parms.
4106 Parms which have partial registers are not stored here,
4107 but we do preallocate space here if they want that. */
4109 for (i
= 0; i
< num_actuals
; i
++)
4111 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
4113 rtx_insn
*before_arg
= get_last_insn ();
4115 /* We don't allow passing huge (> 2^30 B) arguments
4116 by value. It would cause an overflow later on. */
4117 if (constant_lower_bound (adjusted_args_size
.constant
)
4118 >= (1 << (HOST_BITS_PER_INT
- 2)))
4120 sorry ("passing too large argument on stack");
4124 if (store_one_arg (&args
[i
], argblock
, flags
,
4125 adjusted_args_size
.var
!= 0,
4126 reg_parm_stack_space
)
4128 && check_sibcall_argument_overlap (before_arg
,
4130 sibcall_failure
= 1;
4135 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
4136 gen_rtx_USE (VOIDmode
, args
[i
].stack
),
4140 /* If we have a parm that is passed in registers but not in memory
4141 and whose alignment does not permit a direct copy into registers,
4142 make a group of pseudos that correspond to each register that we
4144 if (STRICT_ALIGNMENT
)
4145 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
4147 /* Now store any partially-in-registers parm.
4148 This is the last place a block-move can happen. */
4150 for (i
= 0; i
< num_actuals
; i
++)
4151 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
4153 rtx_insn
*before_arg
= get_last_insn ();
4155 /* On targets with weird calling conventions (e.g. PA) it's
4156 hard to ensure that all cases of argument overlap between
4157 stack and registers work. Play it safe and bail out. */
4158 if (ARGS_GROW_DOWNWARD
&& !STACK_GROWS_DOWNWARD
)
4160 sibcall_failure
= 1;
4164 if (store_one_arg (&args
[i
], argblock
, flags
,
4165 adjusted_args_size
.var
!= 0,
4166 reg_parm_stack_space
)
4168 && check_sibcall_argument_overlap (before_arg
,
4170 sibcall_failure
= 1;
4173 bool any_regs
= false;
4174 for (i
= 0; i
< num_actuals
; i
++)
4175 if (args
[i
].reg
!= NULL_RTX
)
4178 targetm
.calls
.call_args (args
[i
].reg
, funtype
);
4181 targetm
.calls
.call_args (pc_rtx
, funtype
);
4183 /* Figure out the register where the value, if any, will come back. */
4185 if (TYPE_MODE (rettype
) != VOIDmode
4186 && ! structure_value_addr
)
4188 if (pcc_struct_value
)
4189 valreg
= hard_function_value (build_pointer_type (rettype
),
4190 fndecl
, NULL
, (pass
== 0));
4192 valreg
= hard_function_value (rettype
, fndecl
, fntype
,
4195 /* If VALREG is a PARALLEL whose first member has a zero
4196 offset, use that. This is for targets such as m68k that
4197 return the same value in multiple places. */
4198 if (GET_CODE (valreg
) == PARALLEL
)
4200 rtx elem
= XVECEXP (valreg
, 0, 0);
4201 rtx where
= XEXP (elem
, 0);
4202 rtx offset
= XEXP (elem
, 1);
4203 if (offset
== const0_rtx
4204 && GET_MODE (where
) == GET_MODE (valreg
))
4209 /* If register arguments require space on the stack and stack space
4210 was not preallocated, allocate stack space here for arguments
4211 passed in registers. */
4212 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
4213 && !ACCUMULATE_OUTGOING_ARGS
4214 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
4215 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
4217 /* Pass the function the address in which to return a
4219 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
4221 structure_value_addr
4222 = convert_memory_address (Pmode
, structure_value_addr
);
4223 emit_move_insn (struct_value
,
4225 force_operand (structure_value_addr
,
4228 if (REG_P (struct_value
))
4229 use_reg (&call_fusage
, struct_value
);
4232 after_args
= get_last_insn ();
4233 funexp
= prepare_call_address (fndecl
? fndecl
: fntype
, funexp
,
4234 static_chain_value
, &call_fusage
,
4235 reg_parm_seen
, flags
);
4237 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
4238 pass
== 0, &sibcall_failure
);
4240 /* Save a pointer to the last insn before the call, so that we can
4241 later safely search backwards to find the CALL_INSN. */
4242 before_call
= get_last_insn ();
4244 /* Set up next argument register. For sibling calls on machines
4245 with register windows this should be the incoming register. */
4247 next_arg_reg
= targetm
.calls
.function_incoming_arg
4248 (args_so_far
, function_arg_info::end_marker ());
4250 next_arg_reg
= targetm
.calls
.function_arg
4251 (args_so_far
, function_arg_info::end_marker ());
4253 if (pass
== 1 && (return_flags
& ERF_RETURNS_ARG
))
4255 int arg_nr
= return_flags
& ERF_RETURN_ARG_MASK
;
4256 arg_nr
= num_actuals
- arg_nr
- 1;
4258 && arg_nr
< num_actuals
4262 && GET_MODE (args
[arg_nr
].reg
) == GET_MODE (valreg
))
4264 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args
[arg_nr
].tree_value
)),
4265 gen_rtx_SET (valreg
, args
[arg_nr
].reg
),
4268 /* All arguments and registers used for the call must be set up by
4271 /* Stack must be properly aligned now. */
4273 || multiple_p (stack_pointer_delta
,
4274 preferred_unit_stack_boundary
));
4276 /* Generate the actual call instruction. */
4277 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
4278 adjusted_args_size
.constant
, struct_value_size
,
4279 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
4280 flags
, args_so_far
);
4284 rtx_call_insn
*last
;
4285 rtx datum
= NULL_RTX
;
4286 if (fndecl
!= NULL_TREE
)
4288 datum
= XEXP (DECL_RTL (fndecl
), 0);
4289 gcc_assert (datum
!= NULL_RTX
4290 && GET_CODE (datum
) == SYMBOL_REF
);
4292 last
= last_call_insn ();
4293 add_reg_note (last
, REG_CALL_DECL
, datum
);
4296 /* If the call setup or the call itself overlaps with anything
4297 of the argument setup we probably clobbered our call address.
4298 In that case we can't do sibcalls. */
4300 && check_sibcall_argument_overlap (after_args
, 0, 0))
4301 sibcall_failure
= 1;
4303 /* If a non-BLKmode value is returned at the most significant end
4304 of a register, shift the register right by the appropriate amount
4305 and update VALREG accordingly. BLKmode values are handled by the
4306 group load/store machinery below. */
4307 if (!structure_value_addr
4308 && !pcc_struct_value
4309 && TYPE_MODE (rettype
) != VOIDmode
4310 && TYPE_MODE (rettype
) != BLKmode
4312 && targetm
.calls
.return_in_msb (rettype
))
4314 if (shift_return_value (TYPE_MODE (rettype
), false, valreg
))
4315 sibcall_failure
= 1;
4316 valreg
= gen_rtx_REG (TYPE_MODE (rettype
), REGNO (valreg
));
4319 if (pass
&& (flags
& ECF_MALLOC
))
4321 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
4322 rtx_insn
*last
, *insns
;
4324 /* The return value from a malloc-like function is a pointer. */
4325 if (TREE_CODE (rettype
) == POINTER_TYPE
)
4326 mark_reg_pointer (temp
, MALLOC_ABI_ALIGNMENT
);
4328 emit_move_insn (temp
, valreg
);
4330 /* The return value from a malloc-like function cannot alias
4332 last
= get_last_insn ();
4333 add_reg_note (last
, REG_NOALIAS
, temp
);
4335 /* Write out the sequence. */
4336 insns
= get_insns ();
4342 /* For calls to `setjmp', etc., inform
4343 function.c:setjmp_warnings that it should complain if
4344 nonvolatile values are live. For functions that cannot
4345 return, inform flow that control does not fall through. */
4347 if ((flags
& ECF_NORETURN
) || pass
== 0)
4349 /* The barrier must be emitted
4350 immediately after the CALL_INSN. Some ports emit more
4351 than just a CALL_INSN above, so we must search for it here. */
4353 rtx_insn
*last
= get_last_insn ();
4354 while (!CALL_P (last
))
4356 last
= PREV_INSN (last
);
4357 /* There was no CALL_INSN? */
4358 gcc_assert (last
!= before_call
);
4361 emit_barrier_after (last
);
4363 /* Stack adjustments after a noreturn call are dead code.
4364 However when NO_DEFER_POP is in effect, we must preserve
4365 stack_pointer_delta. */
4366 if (inhibit_defer_pop
== 0)
4368 stack_pointer_delta
= old_stack_allocated
;
4369 pending_stack_adjust
= 0;
4373 /* If value type not void, return an rtx for the value. */
4375 if (TYPE_MODE (rettype
) == VOIDmode
4377 target
= const0_rtx
;
4378 else if (structure_value_addr
)
4380 if (target
== 0 || !MEM_P (target
))
4383 = gen_rtx_MEM (TYPE_MODE (rettype
),
4384 memory_address (TYPE_MODE (rettype
),
4385 structure_value_addr
));
4386 set_mem_attributes (target
, rettype
, 1);
4389 else if (pcc_struct_value
)
4391 /* This is the special C++ case where we need to
4392 know what the true target was. We take care to
4393 never use this value more than once in one expression. */
4394 target
= gen_rtx_MEM (TYPE_MODE (rettype
),
4395 copy_to_reg (valreg
));
4396 set_mem_attributes (target
, rettype
, 1);
4398 /* Handle calls that return values in multiple non-contiguous locations.
4399 The Irix 6 ABI has examples of this. */
4400 else if (GET_CODE (valreg
) == PARALLEL
)
4403 target
= emit_group_move_into_temps (valreg
);
4404 else if (rtx_equal_p (target
, valreg
))
4406 else if (GET_CODE (target
) == PARALLEL
)
4407 /* Handle the result of a emit_group_move_into_temps
4408 call in the previous pass. */
4409 emit_group_move (target
, valreg
);
4411 emit_group_store (target
, valreg
, rettype
,
4412 int_size_in_bytes (rettype
));
4415 && GET_MODE (target
) == TYPE_MODE (rettype
)
4416 && GET_MODE (target
) == GET_MODE (valreg
))
4418 bool may_overlap
= false;
4420 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
4421 reg to a plain register. */
4422 if (!REG_P (target
) || HARD_REGISTER_P (target
))
4423 valreg
= avoid_likely_spilled_reg (valreg
);
4425 /* If TARGET is a MEM in the argument area, and we have
4426 saved part of the argument area, then we can't store
4427 directly into TARGET as it may get overwritten when we
4428 restore the argument save area below. Don't work too
4429 hard though and simply force TARGET to a register if it
4430 is a MEM; the optimizer is quite likely to sort it out. */
4431 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
4432 for (i
= 0; i
< num_actuals
; i
++)
4433 if (args
[i
].save_area
)
4440 target
= copy_to_reg (valreg
);
4443 /* TARGET and VALREG cannot be equal at this point
4444 because the latter would not have
4445 REG_FUNCTION_VALUE_P true, while the former would if
4446 it were referring to the same register.
4448 If they refer to the same register, this move will be
4449 a no-op, except when function inlining is being
4451 emit_move_insn (target
, valreg
);
4453 /* If we are setting a MEM, this code must be executed.
4454 Since it is emitted after the call insn, sibcall
4455 optimization cannot be performed in that case. */
4457 sibcall_failure
= 1;
4461 target
= copy_to_reg (avoid_likely_spilled_reg (valreg
));
4463 /* If we promoted this return value, make the proper SUBREG.
4464 TARGET might be const0_rtx here, so be careful. */
4466 && TYPE_MODE (rettype
) != BLKmode
4467 && GET_MODE (target
) != TYPE_MODE (rettype
))
4469 tree type
= rettype
;
4470 int unsignedp
= TYPE_UNSIGNED (type
);
4473 /* Ensure we promote as expected, and get the new unsignedness. */
4474 pmode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
4476 gcc_assert (GET_MODE (target
) == pmode
);
4478 poly_uint64 offset
= subreg_lowpart_offset (TYPE_MODE (type
),
4480 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
4481 SUBREG_PROMOTED_VAR_P (target
) = 1;
4482 SUBREG_PROMOTED_SET (target
, unsignedp
);
4485 /* If size of args is variable or this was a constructor call for a stack
4486 argument, restore saved stack-pointer value. */
4488 if (old_stack_level
)
4490 rtx_insn
*prev
= get_last_insn ();
4492 emit_stack_restore (SAVE_BLOCK
, old_stack_level
);
4493 stack_pointer_delta
= old_stack_pointer_delta
;
4495 fixup_args_size_notes (prev
, get_last_insn (), stack_pointer_delta
);
4497 pending_stack_adjust
= old_pending_adj
;
4498 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
4499 stack_arg_under_construction
= old_stack_arg_under_construction
;
4500 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4501 stack_usage_map
= initial_stack_usage_map
;
4502 stack_usage_watermark
= initial_stack_usage_watermark
;
4503 sibcall_failure
= 1;
4505 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
4507 #ifdef REG_PARM_STACK_SPACE
4509 restore_fixed_argument_area (save_area
, argblock
,
4510 high_to_save
, low_to_save
);
4513 /* If we saved any argument areas, restore them. */
4514 for (i
= 0; i
< num_actuals
; i
++)
4515 if (args
[i
].save_area
)
4517 machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
4519 = gen_rtx_MEM (save_mode
,
4520 memory_address (save_mode
,
4521 XEXP (args
[i
].stack_slot
, 0)));
4523 if (save_mode
!= BLKmode
)
4524 emit_move_insn (stack_area
, args
[i
].save_area
);
4526 emit_block_move (stack_area
, args
[i
].save_area
,
4528 (args
[i
].locate
.size
.constant
, Pmode
)),
4529 BLOCK_OP_CALL_PARM
);
4532 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4533 stack_usage_map
= initial_stack_usage_map
;
4534 stack_usage_watermark
= initial_stack_usage_watermark
;
4537 /* If this was alloca, record the new stack level. */
4538 if (flags
& ECF_MAY_BE_ALLOCA
)
4539 record_new_stack_level ();
4541 /* Free up storage we no longer need. */
4542 for (i
= 0; i
< num_actuals
; ++i
)
4543 free (args
[i
].aligned_regs
);
4545 targetm
.calls
.end_call_args ();
4547 insns
= get_insns ();
4552 tail_call_insns
= insns
;
4554 /* Restore the pending stack adjustment now that we have
4555 finished generating the sibling call sequence. */
4557 restore_pending_stack_adjust (&save
);
4559 /* Prepare arg structure for next iteration. */
4560 for (i
= 0; i
< num_actuals
; i
++)
4563 args
[i
].aligned_regs
= 0;
4567 sbitmap_free (stored_args_map
);
4568 internal_arg_pointer_exp_state
.scan_start
= NULL
;
4569 internal_arg_pointer_exp_state
.cache
.release ();
4573 normal_call_insns
= insns
;
4575 /* Verify that we've deallocated all the stack we used. */
4576 gcc_assert ((flags
& ECF_NORETURN
)
4577 || known_eq (old_stack_allocated
,
4579 - pending_stack_adjust
));
4582 /* If something prevents making this a sibling call,
4583 zero out the sequence. */
4584 if (sibcall_failure
)
4585 tail_call_insns
= NULL
;
4590 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
4591 arguments too, as argument area is now clobbered by the call. */
4592 if (tail_call_insns
)
4594 emit_insn (tail_call_insns
);
4595 crtl
->tail_call_emit
= true;
4599 emit_insn (normal_call_insns
);
4601 /* Ideally we'd emit a message for all of the ways that it could
4603 maybe_complain_about_tail_call (exp
, "tail call production failed");
4606 currently_expanding_call
--;
4608 free (stack_usage_map_buf
);
4613 /* A sibling call sequence invalidates any REG_EQUIV notes made for
4614 this function's incoming arguments.
4616 At the start of RTL generation we know the only REG_EQUIV notes
4617 in the rtl chain are those for incoming arguments, so we can look
4618 for REG_EQUIV notes between the start of the function and the
4619 NOTE_INSN_FUNCTION_BEG.
4621 This is (slight) overkill. We could keep track of the highest
4622 argument we clobber and be more selective in removing notes, but it
4623 does not seem to be worth the effort. */
4626 fixup_tail_calls (void)
4630 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4634 /* There are never REG_EQUIV notes for the incoming arguments
4635 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
4637 && NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
)
4640 note
= find_reg_note (insn
, REG_EQUIV
, 0);
4642 remove_note (insn
, note
);
4643 note
= find_reg_note (insn
, REG_EQUIV
, 0);
4648 /* Traverse a list of TYPES and expand all complex types into their
4651 split_complex_types (tree types
)
4655 /* Before allocating memory, check for the common case of no complex. */
4656 for (p
= types
; p
; p
= TREE_CHAIN (p
))
4658 tree type
= TREE_VALUE (p
);
4659 if (TREE_CODE (type
) == COMPLEX_TYPE
4660 && targetm
.calls
.split_complex_arg (type
))
4666 types
= copy_list (types
);
4668 for (p
= types
; p
; p
= TREE_CHAIN (p
))
4670 tree complex_type
= TREE_VALUE (p
);
4672 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
4673 && targetm
.calls
.split_complex_arg (complex_type
))
4677 /* Rewrite complex type with component type. */
4678 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
4679 next
= TREE_CHAIN (p
);
4681 /* Add another component type for the imaginary part. */
4682 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
4683 TREE_CHAIN (p
) = imag
;
4684 TREE_CHAIN (imag
) = next
;
4686 /* Skip the newly created node. */
4694 /* Output a library call to function ORGFUN (a SYMBOL_REF rtx)
4695 for a value of mode OUTMODE,
4696 with NARGS different arguments, passed as ARGS.
4697 Store the return value if RETVAL is nonzero: store it in VALUE if
4698 VALUE is nonnull, otherwise pick a convenient location. In either
4699 case return the location of the stored value.
4701 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4702 `const' calls, LCT_PURE for `pure' calls, or another LCT_ value for
4703 other types of library calls. */
4706 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
4707 enum libcall_type fn_type
,
4708 machine_mode outmode
, int nargs
, rtx_mode_t
*args
)
4710 /* Total size in bytes of all the stack-parms scanned so far. */
4711 struct args_size args_size
;
4712 /* Size of arguments before any adjustments (such as rounding). */
4713 struct args_size original_args_size
;
4716 /* Todo, choose the correct decl type of orgfun. Sadly this information
4717 isn't present here, so we default to native calling abi here. */
4718 tree fndecl ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
4719 tree fntype ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
4722 CUMULATIVE_ARGS args_so_far_v
;
4723 cumulative_args_t args_so_far
;
4730 struct locate_and_pad_arg_data locate
;
4734 int old_inhibit_defer_pop
= inhibit_defer_pop
;
4735 rtx call_fusage
= 0;
4738 int pcc_struct_value
= 0;
4739 poly_int64 struct_value_size
= 0;
4741 int reg_parm_stack_space
= 0;
4743 rtx_insn
*before_call
;
4744 bool have_push_fusage
;
4745 tree tfom
; /* type_for_mode (outmode, 0) */
4747 #ifdef REG_PARM_STACK_SPACE
4748 /* Define the boundary of the register parm stack space that needs to be
4750 int low_to_save
= 0, high_to_save
= 0;
4751 rtx save_area
= 0; /* Place that it is saved. */
4754 /* Size of the stack reserved for parameter registers. */
4755 unsigned int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
4756 char *initial_stack_usage_map
= stack_usage_map
;
4757 unsigned HOST_WIDE_INT initial_stack_usage_watermark
= stack_usage_watermark
;
4758 char *stack_usage_map_buf
= NULL
;
4760 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
4762 #ifdef REG_PARM_STACK_SPACE
4763 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
4766 /* By default, library functions cannot throw. */
4767 flags
= ECF_NOTHROW
;
4780 flags
|= ECF_NORETURN
;
4783 flags
&= ~ECF_NOTHROW
;
4785 case LCT_RETURNS_TWICE
:
4786 flags
= ECF_RETURNS_TWICE
;
4791 /* Ensure current function's preferred stack boundary is at least
4793 if (crtl
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
4794 crtl
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
4796 /* If this kind of value comes back in memory,
4797 decide where in memory it should come back. */
4798 if (outmode
!= VOIDmode
)
4800 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
4801 if (aggregate_value_p (tfom
, 0))
4803 #ifdef PCC_STATIC_STRUCT_RETURN
4805 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
4806 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
4807 pcc_struct_value
= 1;
4809 value
= gen_reg_rtx (outmode
);
4810 #else /* not PCC_STATIC_STRUCT_RETURN */
4811 struct_value_size
= GET_MODE_SIZE (outmode
);
4812 if (value
!= 0 && MEM_P (value
))
4815 mem_value
= assign_temp (tfom
, 1, 1);
4817 /* This call returns a big structure. */
4818 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
4822 tfom
= void_type_node
;
4824 /* ??? Unfinished: must pass the memory address as an argument. */
4826 /* Copy all the libcall-arguments out of the varargs data
4827 and into a vector ARGVEC.
4829 Compute how to pass each argument. We only support a very small subset
4830 of the full argument passing conventions to limit complexity here since
4831 library functions shouldn't have many args. */
4833 argvec
= XALLOCAVEC (struct arg
, nargs
+ 1);
4834 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
4836 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
4837 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v
, outmode
, fun
);
4839 INIT_CUMULATIVE_ARGS (args_so_far_v
, NULL_TREE
, fun
, 0, nargs
);
4841 args_so_far
= pack_cumulative_args (&args_so_far_v
);
4843 args_size
.constant
= 0;
4850 /* If there's a structure value address to be passed,
4851 either pass it in the special place, or pass it as an extra argument. */
4852 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
4854 rtx addr
= XEXP (mem_value
, 0);
4858 /* Make sure it is a reasonable operand for a move or push insn. */
4859 if (!REG_P (addr
) && !MEM_P (addr
)
4860 && !(CONSTANT_P (addr
)
4861 && targetm
.legitimate_constant_p (Pmode
, addr
)))
4862 addr
= force_operand (addr
, NULL_RTX
);
4864 argvec
[count
].value
= addr
;
4865 argvec
[count
].mode
= Pmode
;
4866 argvec
[count
].partial
= 0;
4868 function_arg_info
ptr_arg (Pmode
, /*named=*/true);
4869 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
, ptr_arg
);
4870 gcc_assert (targetm
.calls
.arg_partial_bytes (args_so_far
, ptr_arg
) == 0);
4872 locate_and_pad_parm (Pmode
, NULL_TREE
,
4873 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4876 argvec
[count
].reg
!= 0,
4878 reg_parm_stack_space
, 0,
4879 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
4881 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
4882 || reg_parm_stack_space
> 0)
4883 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
4885 targetm
.calls
.function_arg_advance (args_so_far
, ptr_arg
);
4890 for (unsigned int i
= 0; count
< nargs
; i
++, count
++)
4892 rtx val
= args
[i
].first
;
4893 machine_mode mode
= args
[i
].second
;
4896 /* We cannot convert the arg value to the mode the library wants here;
4897 must do it earlier where we know the signedness of the arg. */
4898 gcc_assert (mode
!= BLKmode
4899 && (GET_MODE (val
) == mode
|| GET_MODE (val
) == VOIDmode
));
4901 /* Make sure it is a reasonable operand for a move or push insn. */
4902 if (!REG_P (val
) && !MEM_P (val
)
4903 && !(CONSTANT_P (val
) && targetm
.legitimate_constant_p (mode
, val
)))
4904 val
= force_operand (val
, NULL_RTX
);
4906 function_arg_info
orig_arg (mode
, /*named=*/true);
4907 if (pass_by_reference (&args_so_far_v
, orig_arg
))
4910 int must_copy
= !reference_callee_copied (&args_so_far_v
, orig_arg
);
4912 /* If this was a CONST function, it is now PURE since it now
4914 if (flags
& ECF_CONST
)
4916 flags
&= ~ECF_CONST
;
4920 if (MEM_P (val
) && !must_copy
)
4922 tree val_expr
= MEM_EXPR (val
);
4924 mark_addressable (val_expr
);
4929 slot
= assign_temp (lang_hooks
.types
.type_for_mode (mode
, 0),
4931 emit_move_insn (slot
, val
);
4934 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
4935 gen_rtx_USE (VOIDmode
, slot
),
4938 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
4939 gen_rtx_CLOBBER (VOIDmode
,
4944 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
4947 mode
= promote_function_mode (NULL_TREE
, mode
, &unsigned_p
, NULL_TREE
, 0);
4948 function_arg_info
arg (mode
, /*named=*/true);
4949 argvec
[count
].mode
= mode
;
4950 argvec
[count
].value
= convert_modes (mode
, GET_MODE (val
), val
, unsigned_p
);
4951 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
, arg
);
4953 argvec
[count
].partial
4954 = targetm
.calls
.arg_partial_bytes (args_so_far
, arg
);
4956 if (argvec
[count
].reg
== 0
4957 || argvec
[count
].partial
!= 0
4958 || reg_parm_stack_space
> 0)
4960 locate_and_pad_parm (mode
, NULL_TREE
,
4961 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4964 argvec
[count
].reg
!= 0,
4966 reg_parm_stack_space
, argvec
[count
].partial
,
4967 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
4968 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
4969 gcc_assert (!argvec
[count
].locate
.size
.var
);
4971 #ifdef BLOCK_REG_PADDING
4973 /* The argument is passed entirely in registers. See at which
4974 end it should be padded. */
4975 argvec
[count
].locate
.where_pad
=
4976 BLOCK_REG_PADDING (mode
, NULL_TREE
,
4977 known_le (GET_MODE_SIZE (mode
), UNITS_PER_WORD
));
4980 targetm
.calls
.function_arg_advance (args_so_far
, arg
);
4983 for (int i
= 0; i
< nargs
; i
++)
4984 if (reg_parm_stack_space
> 0
4985 || argvec
[i
].reg
== 0
4986 || argvec
[i
].partial
!= 0)
4987 update_stack_alignment_for_call (&argvec
[i
].locate
);
4989 /* If this machine requires an external definition for library
4990 functions, write one out. */
4991 assemble_external_libcall (fun
);
4993 original_args_size
= args_size
;
4994 args_size
.constant
= (aligned_upper_bound (args_size
.constant
4995 + stack_pointer_delta
,
4997 - stack_pointer_delta
);
4999 args_size
.constant
= upper_bound (args_size
.constant
,
5000 reg_parm_stack_space
);
5002 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
5003 args_size
.constant
-= reg_parm_stack_space
;
5005 crtl
->outgoing_args_size
= upper_bound (crtl
->outgoing_args_size
,
5006 args_size
.constant
);
5008 if (flag_stack_usage_info
&& !ACCUMULATE_OUTGOING_ARGS
)
5010 poly_int64 pushed
= args_size
.constant
+ pending_stack_adjust
;
5011 current_function_pushed_stack_size
5012 = upper_bound (current_function_pushed_stack_size
, pushed
);
5015 if (ACCUMULATE_OUTGOING_ARGS
)
5017 /* Since the stack pointer will never be pushed, it is possible for
5018 the evaluation of a parm to clobber something we have already
5019 written to the stack. Since most function calls on RISC machines
5020 do not use the stack, this is uncommon, but must work correctly.
5022 Therefore, we save any area of the stack that was already written
5023 and that we are using. Here we set up to do this by making a new
5024 stack usage map from the old one.
5026 Another approach might be to try to reorder the argument
5027 evaluations to avoid this conflicting stack usage. */
5029 needed
= args_size
.constant
;
5031 /* Since we will be writing into the entire argument area, the
5032 map must be allocated for its entire size, not just the part that
5033 is the responsibility of the caller. */
5034 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
5035 needed
+= reg_parm_stack_space
;
5037 poly_int64 limit
= needed
;
5038 if (ARGS_GROW_DOWNWARD
)
5041 /* For polynomial sizes, this is the maximum possible size needed
5042 for arguments with a constant size and offset. */
5043 HOST_WIDE_INT const_limit
= constant_lower_bound (limit
);
5044 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
5047 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
5048 stack_usage_map
= stack_usage_map_buf
;
5050 if (initial_highest_arg_in_use
)
5051 memcpy (stack_usage_map
, initial_stack_usage_map
,
5052 initial_highest_arg_in_use
);
5054 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
5055 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
5056 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
5059 /* We must be careful to use virtual regs before they're instantiated,
5060 and real regs afterwards. Loop optimization, for example, can create
5061 new libcalls after we've instantiated the virtual regs, and if we
5062 use virtuals anyway, they won't match the rtl patterns. */
5064 if (virtuals_instantiated
)
5065 argblock
= plus_constant (Pmode
, stack_pointer_rtx
,
5066 STACK_POINTER_OFFSET
);
5068 argblock
= virtual_outgoing_args_rtx
;
5073 argblock
= push_block (gen_int_mode (args_size
.constant
, Pmode
), 0, 0);
5076 /* We push args individually in reverse order, perform stack alignment
5077 before the first push (the last arg). */
5079 anti_adjust_stack (gen_int_mode (args_size
.constant
5080 - original_args_size
.constant
,
5085 #ifdef REG_PARM_STACK_SPACE
5086 if (ACCUMULATE_OUTGOING_ARGS
)
5088 /* The argument list is the property of the called routine and it
5089 may clobber it. If the fixed area has been used for previous
5090 parameters, we must save and restore it. */
5091 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
5092 &low_to_save
, &high_to_save
);
5096 /* When expanding a normal call, args are stored in push order,
5097 which is the reverse of what we have here. */
5098 bool any_regs
= false;
5099 for (int i
= nargs
; i
-- > 0; )
5100 if (argvec
[i
].reg
!= NULL_RTX
)
5102 targetm
.calls
.call_args (argvec
[i
].reg
, NULL_TREE
);
5106 targetm
.calls
.call_args (pc_rtx
, NULL_TREE
);
5108 /* Push the args that need to be pushed. */
5110 have_push_fusage
= false;
5112 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5113 are to be pushed. */
5114 for (count
= 0; count
< nargs
; count
++, argnum
--)
5116 machine_mode mode
= argvec
[argnum
].mode
;
5117 rtx val
= argvec
[argnum
].value
;
5118 rtx reg
= argvec
[argnum
].reg
;
5119 int partial
= argvec
[argnum
].partial
;
5120 unsigned int parm_align
= argvec
[argnum
].locate
.boundary
;
5121 poly_int64 lower_bound
= 0, upper_bound
= 0;
5123 if (! (reg
!= 0 && partial
== 0))
5127 if (ACCUMULATE_OUTGOING_ARGS
)
5129 /* If this is being stored into a pre-allocated, fixed-size,
5130 stack area, save any previous data at that location. */
5132 if (ARGS_GROW_DOWNWARD
)
5134 /* stack_slot is negative, but we want to index stack_usage_map
5135 with positive values. */
5136 upper_bound
= -argvec
[argnum
].locate
.slot_offset
.constant
+ 1;
5137 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
5141 lower_bound
= argvec
[argnum
].locate
.slot_offset
.constant
;
5142 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
5145 if (stack_region_maybe_used_p (lower_bound
, upper_bound
,
5146 reg_parm_stack_space
))
5148 /* We need to make a save area. */
5150 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
5151 machine_mode save_mode
5152 = int_mode_for_size (size
, 1).else_blk ();
5154 = plus_constant (Pmode
, argblock
,
5155 argvec
[argnum
].locate
.offset
.constant
);
5157 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
5159 if (save_mode
== BLKmode
)
5161 argvec
[argnum
].save_area
5162 = assign_stack_temp (BLKmode
,
5163 argvec
[argnum
].locate
.size
.constant
5166 emit_block_move (validize_mem
5167 (copy_rtx (argvec
[argnum
].save_area
)),
5170 (argvec
[argnum
].locate
.size
.constant
,
5172 BLOCK_OP_CALL_PARM
);
5176 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
5178 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
5183 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, parm_align
,
5184 partial
, reg
, 0, argblock
,
5186 (argvec
[argnum
].locate
.offset
.constant
, Pmode
)),
5187 reg_parm_stack_space
,
5188 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
), false);
5190 /* Now mark the segment we just used. */
5191 if (ACCUMULATE_OUTGOING_ARGS
)
5192 mark_stack_region_used (lower_bound
, upper_bound
);
5196 /* Indicate argument access so that alias.c knows that these
5199 use
= plus_constant (Pmode
, argblock
,
5200 argvec
[argnum
].locate
.offset
.constant
);
5201 else if (have_push_fusage
)
5205 /* When arguments are pushed, trying to tell alias.c where
5206 exactly this argument is won't work, because the
5207 auto-increment causes confusion. So we merely indicate
5208 that we access something with a known mode somewhere on
5210 use
= gen_rtx_PLUS (Pmode
, stack_pointer_rtx
,
5211 gen_rtx_SCRATCH (Pmode
));
5212 have_push_fusage
= true;
5214 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
5215 use
= gen_rtx_USE (VOIDmode
, use
);
5216 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
5222 fun
= prepare_call_address (NULL
, fun
, NULL
, &call_fusage
, 0, 0);
5224 /* Now load any reg parms into their regs. */
5226 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5227 are to be pushed. */
5228 for (count
= 0; count
< nargs
; count
++, argnum
--)
5230 machine_mode mode
= argvec
[argnum
].mode
;
5231 rtx val
= argvec
[argnum
].value
;
5232 rtx reg
= argvec
[argnum
].reg
;
5233 int partial
= argvec
[argnum
].partial
;
5235 /* Handle calls that pass values in multiple non-contiguous
5236 locations. The PA64 has examples of this for library calls. */
5237 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
5238 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
5239 else if (reg
!= 0 && partial
== 0)
5241 emit_move_insn (reg
, val
);
5242 #ifdef BLOCK_REG_PADDING
5243 poly_int64 size
= GET_MODE_SIZE (argvec
[argnum
].mode
);
5245 /* Copied from load_register_parameters. */
5247 /* Handle case where we have a value that needs shifting
5248 up to the msb. eg. a QImode value and we're padding
5249 upward on a BYTES_BIG_ENDIAN machine. */
5250 if (known_lt (size
, UNITS_PER_WORD
)
5251 && (argvec
[argnum
].locate
.where_pad
5252 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
5255 poly_int64 shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
5257 /* Assigning REG here rather than a temp makes CALL_FUSAGE
5258 report the whole reg as used. Strictly speaking, the
5259 call only uses SIZE bytes at the msb end, but it doesn't
5260 seem worth generating rtl to say that. */
5261 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
5262 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
, shift
, reg
, 1);
5264 emit_move_insn (reg
, x
);
5272 /* Any regs containing parms remain in use through the call. */
5273 for (count
= 0; count
< nargs
; count
++)
5275 rtx reg
= argvec
[count
].reg
;
5276 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
5277 use_group_regs (&call_fusage
, reg
);
5280 int partial
= argvec
[count
].partial
;
5284 gcc_assert (partial
% UNITS_PER_WORD
== 0);
5285 nregs
= partial
/ UNITS_PER_WORD
;
5286 use_regs (&call_fusage
, REGNO (reg
), nregs
);
5289 use_reg (&call_fusage
, reg
);
5293 /* Pass the function the address in which to return a structure value. */
5294 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
5296 emit_move_insn (struct_value
,
5298 force_operand (XEXP (mem_value
, 0),
5300 if (REG_P (struct_value
))
5301 use_reg (&call_fusage
, struct_value
);
5304 /* Don't allow popping to be deferred, since then
5305 cse'ing of library calls could delete a call and leave the pop. */
5307 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
5308 ? hard_libcall_value (outmode
, orgfun
) : NULL_RTX
);
5310 /* Stack must be properly aligned now. */
5311 gcc_assert (multiple_p (stack_pointer_delta
,
5312 PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
));
5314 before_call
= get_last_insn ();
5316 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
5317 will set inhibit_defer_pop to that value. */
5318 /* The return type is needed to decide how many bytes the function pops.
5319 Signedness plays no role in that, so for simplicity, we pretend it's
5320 always signed. We also assume that the list of arguments passed has
5321 no impact, so we pretend it is unknown. */
5323 emit_call_1 (fun
, NULL
,
5324 get_identifier (XSTR (orgfun
, 0)),
5325 build_function_type (tfom
, NULL_TREE
),
5326 original_args_size
.constant
, args_size
.constant
,
5328 targetm
.calls
.function_arg (args_so_far
,
5329 function_arg_info::end_marker ()),
5331 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, args_so_far
);
5336 gcc_assert (GET_CODE (datum
) == SYMBOL_REF
);
5337 rtx_call_insn
*last
= last_call_insn ();
5338 add_reg_note (last
, REG_CALL_DECL
, datum
);
5341 /* Right-shift returned value if necessary. */
5342 if (!pcc_struct_value
5343 && TYPE_MODE (tfom
) != BLKmode
5344 && targetm
.calls
.return_in_msb (tfom
))
5346 shift_return_value (TYPE_MODE (tfom
), false, valreg
);
5347 valreg
= gen_rtx_REG (TYPE_MODE (tfom
), REGNO (valreg
));
5350 targetm
.calls
.end_call_args ();
5352 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
5353 that it should complain if nonvolatile values are live. For
5354 functions that cannot return, inform flow that control does not
5356 if (flags
& ECF_NORETURN
)
5358 /* The barrier note must be emitted
5359 immediately after the CALL_INSN. Some ports emit more than
5360 just a CALL_INSN above, so we must search for it here. */
5361 rtx_insn
*last
= get_last_insn ();
5362 while (!CALL_P (last
))
5364 last
= PREV_INSN (last
);
5365 /* There was no CALL_INSN? */
5366 gcc_assert (last
!= before_call
);
5369 emit_barrier_after (last
);
5372 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
5373 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
5374 if (flags
& ECF_NOTHROW
)
5376 rtx_insn
*last
= get_last_insn ();
5377 while (!CALL_P (last
))
5379 last
= PREV_INSN (last
);
5380 /* There was no CALL_INSN? */
5381 gcc_assert (last
!= before_call
);
5384 make_reg_eh_region_note_nothrow_nononlocal (last
);
5387 /* Now restore inhibit_defer_pop to its actual original value. */
5392 /* Copy the value to the right place. */
5393 if (outmode
!= VOIDmode
&& retval
)
5399 if (value
!= mem_value
)
5400 emit_move_insn (value
, mem_value
);
5402 else if (GET_CODE (valreg
) == PARALLEL
)
5405 value
= gen_reg_rtx (outmode
);
5406 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
5410 /* Convert to the proper mode if a promotion has been active. */
5411 if (GET_MODE (valreg
) != outmode
)
5413 int unsignedp
= TYPE_UNSIGNED (tfom
);
5415 gcc_assert (promote_function_mode (tfom
, outmode
, &unsignedp
,
5416 fndecl
? TREE_TYPE (fndecl
) : fntype
, 1)
5417 == GET_MODE (valreg
));
5418 valreg
= convert_modes (outmode
, GET_MODE (valreg
), valreg
, 0);
5422 emit_move_insn (value
, valreg
);
5428 if (ACCUMULATE_OUTGOING_ARGS
)
5430 #ifdef REG_PARM_STACK_SPACE
5432 restore_fixed_argument_area (save_area
, argblock
,
5433 high_to_save
, low_to_save
);
5436 /* If we saved any argument areas, restore them. */
5437 for (count
= 0; count
< nargs
; count
++)
5438 if (argvec
[count
].save_area
)
5440 machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
5441 rtx adr
= plus_constant (Pmode
, argblock
,
5442 argvec
[count
].locate
.offset
.constant
);
5443 rtx stack_area
= gen_rtx_MEM (save_mode
,
5444 memory_address (save_mode
, adr
));
5446 if (save_mode
== BLKmode
)
5447 emit_block_move (stack_area
,
5449 (copy_rtx (argvec
[count
].save_area
)),
5451 (argvec
[count
].locate
.size
.constant
, Pmode
)),
5452 BLOCK_OP_CALL_PARM
);
5454 emit_move_insn (stack_area
, argvec
[count
].save_area
);
5457 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
5458 stack_usage_map
= initial_stack_usage_map
;
5459 stack_usage_watermark
= initial_stack_usage_watermark
;
5462 free (stack_usage_map_buf
);
5469 /* Store a single argument for a function call
5470 into the register or memory area where it must be passed.
5471 *ARG describes the argument value and where to pass it.
5473 ARGBLOCK is the address of the stack-block for all the arguments,
5474 or 0 on a machine where arguments are pushed individually.
5476 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
5477 so must be careful about how the stack is used.
5479 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
5480 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
5481 that we need not worry about saving and restoring the stack.
5483 FNDECL is the declaration of the function we are calling.
5485 Return nonzero if this arg should cause sibcall failure,
5489 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
5490 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
5492 tree pval
= arg
->tree_value
;
5495 poly_int64 used
= 0;
5496 poly_int64 lower_bound
= 0, upper_bound
= 0;
5497 int sibcall_failure
= 0;
5499 if (TREE_CODE (pval
) == ERROR_MARK
)
5502 /* Push a new temporary level for any temporaries we make for
5506 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
5508 /* If this is being stored into a pre-allocated, fixed-size, stack area,
5509 save any previous data at that location. */
5510 if (argblock
&& ! variable_size
&& arg
->stack
)
5512 if (ARGS_GROW_DOWNWARD
)
5514 /* stack_slot is negative, but we want to index stack_usage_map
5515 with positive values. */
5516 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
5518 rtx offset
= XEXP (XEXP (arg
->stack_slot
, 0), 1);
5519 upper_bound
= -rtx_to_poly_int64 (offset
) + 1;
5524 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
5528 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
5530 rtx offset
= XEXP (XEXP (arg
->stack_slot
, 0), 1);
5531 lower_bound
= rtx_to_poly_int64 (offset
);
5536 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
5539 if (stack_region_maybe_used_p (lower_bound
, upper_bound
,
5540 reg_parm_stack_space
))
5542 /* We need to make a save area. */
5543 poly_uint64 size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
5544 machine_mode save_mode
5545 = int_mode_for_size (size
, 1).else_blk ();
5546 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
5547 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
5549 if (save_mode
== BLKmode
)
5552 = assign_temp (TREE_TYPE (arg
->tree_value
), 1, 1);
5553 preserve_temp_slots (arg
->save_area
);
5554 emit_block_move (validize_mem (copy_rtx (arg
->save_area
)),
5557 (arg
->locate
.size
.constant
, Pmode
)),
5558 BLOCK_OP_CALL_PARM
);
5562 arg
->save_area
= gen_reg_rtx (save_mode
);
5563 emit_move_insn (arg
->save_area
, stack_area
);
5569 /* If this isn't going to be placed on both the stack and in registers,
5570 set up the register and number of words. */
5571 if (! arg
->pass_on_stack
)
5573 if (flags
& ECF_SIBCALL
)
5574 reg
= arg
->tail_call_reg
;
5577 partial
= arg
->partial
;
5580 /* Being passed entirely in a register. We shouldn't be called in
5582 gcc_assert (reg
== 0 || partial
!= 0);
5584 /* If this arg needs special alignment, don't load the registers
5586 if (arg
->n_aligned_regs
!= 0)
5589 /* If this is being passed partially in a register, we can't evaluate
5590 it directly into its stack slot. Otherwise, we can. */
5591 if (arg
->value
== 0)
5593 /* stack_arg_under_construction is nonzero if a function argument is
5594 being evaluated directly into the outgoing argument list and
5595 expand_call must take special action to preserve the argument list
5596 if it is called recursively.
5598 For scalar function arguments stack_usage_map is sufficient to
5599 determine which stack slots must be saved and restored. Scalar
5600 arguments in general have pass_on_stack == 0.
5602 If this argument is initialized by a function which takes the
5603 address of the argument (a C++ constructor or a C function
5604 returning a BLKmode structure), then stack_usage_map is
5605 insufficient and expand_call must push the stack around the
5606 function call. Such arguments have pass_on_stack == 1.
5608 Note that it is always safe to set stack_arg_under_construction,
5609 but this generates suboptimal code if set when not needed. */
5611 if (arg
->pass_on_stack
)
5612 stack_arg_under_construction
++;
5614 arg
->value
= expand_expr (pval
,
5616 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
5617 ? NULL_RTX
: arg
->stack
,
5618 VOIDmode
, EXPAND_STACK_PARM
);
5620 /* If we are promoting object (or for any other reason) the mode
5621 doesn't agree, convert the mode. */
5623 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
5624 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
5625 arg
->value
, arg
->unsignedp
);
5627 if (arg
->pass_on_stack
)
5628 stack_arg_under_construction
--;
5631 /* Check for overlap with already clobbered argument area. */
5632 if ((flags
& ECF_SIBCALL
)
5633 && MEM_P (arg
->value
)
5634 && mem_might_overlap_already_clobbered_arg_p (XEXP (arg
->value
, 0),
5635 arg
->locate
.size
.constant
))
5636 sibcall_failure
= 1;
5638 /* Don't allow anything left on stack from computation
5639 of argument to alloca. */
5640 if (flags
& ECF_MAY_BE_ALLOCA
)
5641 do_pending_stack_adjust ();
5643 if (arg
->value
== arg
->stack
)
5644 /* If the value is already in the stack slot, we are done. */
5646 else if (arg
->mode
!= BLKmode
)
5648 unsigned int parm_align
;
5650 /* Argument is a scalar, not entirely passed in registers.
5651 (If part is passed in registers, arg->partial says how much
5652 and emit_push_insn will take care of putting it there.)
5654 Push it, and if its size is less than the
5655 amount of space allocated to it,
5656 also bump stack pointer by the additional space.
5657 Note that in C the default argument promotions
5658 will prevent such mismatches. */
5660 poly_int64 size
= (TYPE_EMPTY_P (TREE_TYPE (pval
))
5661 ? 0 : GET_MODE_SIZE (arg
->mode
));
5663 /* Compute how much space the push instruction will push.
5664 On many machines, pushing a byte will advance the stack
5665 pointer by a halfword. */
5666 #ifdef PUSH_ROUNDING
5667 size
= PUSH_ROUNDING (size
);
5671 /* Compute how much space the argument should get:
5672 round up to a multiple of the alignment for arguments. */
5673 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5675 /* At the moment we don't (need to) support ABIs for which the
5676 padding isn't known at compile time. In principle it should
5677 be easy to add though. */
5678 used
= force_align_up (size
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
5680 /* Compute the alignment of the pushed argument. */
5681 parm_align
= arg
->locate
.boundary
;
5682 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5685 poly_int64 pad
= used
- size
;
5686 unsigned int pad_align
= known_alignment (pad
) * BITS_PER_UNIT
;
5688 parm_align
= MIN (parm_align
, pad_align
);
5691 /* This isn't already where we want it on the stack, so put it there.
5692 This can either be done with push or copy insns. */
5693 if (maybe_ne (used
, 0)
5694 && !emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
),
5695 NULL_RTX
, parm_align
, partial
, reg
, used
- size
,
5696 argblock
, ARGS_SIZE_RTX (arg
->locate
.offset
),
5697 reg_parm_stack_space
,
5698 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
), true))
5699 sibcall_failure
= 1;
5701 /* Unless this is a partially-in-register argument, the argument is now
5704 arg
->value
= arg
->stack
;
5708 /* BLKmode, at least partly to be pushed. */
5710 unsigned int parm_align
;
5714 /* Pushing a nonscalar.
5715 If part is passed in registers, PARTIAL says how much
5716 and emit_push_insn will take care of putting it there. */
5718 /* Round its size up to a multiple
5719 of the allocation unit for arguments. */
5721 if (arg
->locate
.size
.var
!= 0)
5724 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
5728 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
5729 for BLKmode is careful to avoid it. */
5730 excess
= (arg
->locate
.size
.constant
5731 - arg_int_size_in_bytes (TREE_TYPE (pval
))
5733 size_rtx
= expand_expr (arg_size_in_bytes (TREE_TYPE (pval
)),
5734 NULL_RTX
, TYPE_MODE (sizetype
),
5738 parm_align
= arg
->locate
.boundary
;
5740 /* When an argument is padded down, the block is aligned to
5741 PARM_BOUNDARY, but the actual argument isn't. */
5742 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5745 if (arg
->locate
.size
.var
)
5746 parm_align
= BITS_PER_UNIT
;
5749 unsigned int excess_align
5750 = known_alignment (excess
) * BITS_PER_UNIT
;
5751 if (excess_align
!= 0)
5752 parm_align
= MIN (parm_align
, excess_align
);
5756 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
5758 /* emit_push_insn might not work properly if arg->value and
5759 argblock + arg->locate.offset areas overlap. */
5763 if (strip_offset (XEXP (x
, 0), &i
)
5764 == crtl
->args
.internal_arg_pointer
)
5766 /* arg.locate doesn't contain the pretend_args_size offset,
5767 it's part of argblock. Ensure we don't count it in I. */
5768 if (STACK_GROWS_DOWNWARD
)
5769 i
-= crtl
->args
.pretend_args_size
;
5771 i
+= crtl
->args
.pretend_args_size
;
5773 /* expand_call should ensure this. */
5774 gcc_assert (!arg
->locate
.offset
.var
5775 && arg
->locate
.size
.var
== 0);
5776 poly_int64 size_val
= rtx_to_poly_int64 (size_rtx
);
5778 if (known_eq (arg
->locate
.offset
.constant
, i
))
5780 /* Even though they appear to be at the same location,
5781 if part of the outgoing argument is in registers,
5782 they aren't really at the same location. Check for
5783 this by making sure that the incoming size is the
5784 same as the outgoing size. */
5785 if (maybe_ne (arg
->locate
.size
.constant
, size_val
))
5786 sibcall_failure
= 1;
5788 else if (maybe_in_range_p (arg
->locate
.offset
.constant
,
5790 sibcall_failure
= 1;
5791 /* Use arg->locate.size.constant instead of size_rtx
5792 because we only care about the part of the argument
5794 else if (maybe_in_range_p (i
, arg
->locate
.offset
.constant
,
5795 arg
->locate
.size
.constant
))
5796 sibcall_failure
= 1;
5800 if (!CONST_INT_P (size_rtx
) || INTVAL (size_rtx
) != 0)
5801 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
5802 parm_align
, partial
, reg
, excess
, argblock
,
5803 ARGS_SIZE_RTX (arg
->locate
.offset
),
5804 reg_parm_stack_space
,
5805 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
), false);
5807 /* Unless this is a partially-in-register argument, the argument is now
5810 ??? Unlike the case above, in which we want the actual
5811 address of the data, so that we can load it directly into a
5812 register, here we want the address of the stack slot, so that
5813 it's properly aligned for word-by-word copying or something
5814 like that. It's not clear that this is always correct. */
5816 arg
->value
= arg
->stack_slot
;
5819 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
5821 tree type
= TREE_TYPE (arg
->tree_value
);
5823 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
5824 int_size_in_bytes (type
));
5827 /* Mark all slots this store used. */
5828 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
5829 && argblock
&& ! variable_size
&& arg
->stack
)
5830 mark_stack_region_used (lower_bound
, upper_bound
);
5832 /* Once we have pushed something, pops can't safely
5833 be deferred during the rest of the arguments. */
5836 /* Free any temporary slots made in processing this argument. */
5839 return sibcall_failure
;
5842 /* Nonzero if we do not know how to pass ARG solely in registers. */
5845 must_pass_in_stack_var_size (const function_arg_info
&arg
)
5850 /* If the type has variable size... */
5851 if (TREE_CODE (TYPE_SIZE (arg
.type
)) != INTEGER_CST
)
5854 /* If the type is marked as addressable (it is required
5855 to be constructed into the stack)... */
5856 if (TREE_ADDRESSABLE (arg
.type
))
5862 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5863 takes trailing padding of a structure into account. */
5864 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5867 must_pass_in_stack_var_size_or_pad (const function_arg_info
&arg
)
5872 /* If the type has variable size... */
5873 if (TREE_CODE (TYPE_SIZE (arg
.type
)) != INTEGER_CST
)
5876 /* If the type is marked as addressable (it is required
5877 to be constructed into the stack)... */
5878 if (TREE_ADDRESSABLE (arg
.type
))
5881 if (TYPE_EMPTY_P (arg
.type
))
5884 /* If the padding and mode of the type is such that a copy into
5885 a register would put it into the wrong part of the register. */
5886 if (arg
.mode
== BLKmode
5887 && int_size_in_bytes (arg
.type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
5888 && (targetm
.calls
.function_arg_padding (arg
.mode
, arg
.type
)
5889 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
5895 /* Return true if TYPE must be passed on the stack when passed to
5896 the "..." arguments of a function. */
5899 must_pass_va_arg_in_stack (tree type
)
5901 function_arg_info
arg (type
, /*named=*/false);
5902 return targetm
.calls
.must_pass_in_stack (arg
);
5905 /* Tell the garbage collector about GTY markers in this source file. */
5906 #include "gt-calls.h"