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
) || !poly_int_tree_p (TYPE_SIZE (type
)))
917 /* If a record type should be passed the same as its first (and only)
918 member, use the type and mode of that member. */
919 if (TREE_CODE (type
) == RECORD_TYPE
&& TYPE_TRANSPARENT_AGGR (type
))
921 arg
.type
= TREE_TYPE (first_field (type
));
922 arg
.mode
= TYPE_MODE (arg
.type
);
926 return targetm
.calls
.pass_by_reference (pack_cumulative_args (ca
), arg
);
929 /* Return true if TYPE should be passed by reference when passed to
930 the "..." arguments of a function. */
933 pass_va_arg_by_reference (tree type
)
935 return pass_by_reference (NULL
, function_arg_info (type
, /*named=*/false));
938 /* Decide whether ARG, which occurs in the state described by CA,
939 should be passed by reference. Return true if so and update
943 apply_pass_by_reference_rules (CUMULATIVE_ARGS
*ca
, function_arg_info
&arg
)
945 if (pass_by_reference (ca
, arg
))
947 arg
.type
= build_pointer_type (arg
.type
);
948 arg
.mode
= TYPE_MODE (arg
.type
);
949 arg
.pass_by_reference
= true;
955 /* Return true if ARG, which is passed by reference, should be callee
956 copied instead of caller copied. */
959 reference_callee_copied (CUMULATIVE_ARGS
*ca
, const function_arg_info
&arg
)
961 if (arg
.type
&& TREE_ADDRESSABLE (arg
.type
))
963 return targetm
.calls
.callee_copies (pack_cumulative_args (ca
), arg
);
967 /* Precompute all register parameters as described by ARGS, storing values
968 into fields within the ARGS array.
970 NUM_ACTUALS indicates the total number elements in the ARGS array.
972 Set REG_PARM_SEEN if we encounter a register parameter. */
975 precompute_register_parameters (int num_actuals
, struct arg_data
*args
,
982 for (i
= 0; i
< num_actuals
; i
++)
983 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
987 if (args
[i
].value
== 0)
990 args
[i
].value
= expand_normal (args
[i
].tree_value
);
991 preserve_temp_slots (args
[i
].value
);
995 /* If we are to promote the function arg to a wider mode,
998 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
1000 = convert_modes (args
[i
].mode
,
1001 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
1002 args
[i
].value
, args
[i
].unsignedp
);
1004 /* If the value is a non-legitimate constant, force it into a
1005 pseudo now. TLS symbols sometimes need a call to resolve. */
1006 if (CONSTANT_P (args
[i
].value
)
1007 && !targetm
.legitimate_constant_p (args
[i
].mode
, args
[i
].value
))
1008 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
1010 /* If we're going to have to load the value by parts, pull the
1011 parts into pseudos. The part extraction process can involve
1012 non-trivial computation. */
1013 if (GET_CODE (args
[i
].reg
) == PARALLEL
)
1015 tree type
= TREE_TYPE (args
[i
].tree_value
);
1016 args
[i
].parallel_value
1017 = emit_group_load_into_temps (args
[i
].reg
, args
[i
].value
,
1018 type
, int_size_in_bytes (type
));
1021 /* If the value is expensive, and we are inside an appropriately
1022 short loop, put the value into a pseudo and then put the pseudo
1025 For small register classes, also do this if this call uses
1026 register parameters. This is to avoid reload conflicts while
1027 loading the parameters registers. */
1029 else if ((! (REG_P (args
[i
].value
)
1030 || (GET_CODE (args
[i
].value
) == SUBREG
1031 && REG_P (SUBREG_REG (args
[i
].value
)))))
1032 && args
[i
].mode
!= BLKmode
1033 && (set_src_cost (args
[i
].value
, args
[i
].mode
,
1034 optimize_insn_for_speed_p ())
1035 > COSTS_N_INSNS (1))
1037 && targetm
.small_register_classes_for_mode_p (args
[i
].mode
))
1039 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
1043 #ifdef REG_PARM_STACK_SPACE
1045 /* The argument list is the property of the called routine and it
1046 may clobber it. If the fixed area has been used for previous
1047 parameters, we must save and restore it. */
1050 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
1055 /* Compute the boundary of the area that needs to be saved, if any. */
1056 high
= reg_parm_stack_space
;
1057 if (ARGS_GROW_DOWNWARD
)
1060 if (high
> highest_outgoing_arg_in_use
)
1061 high
= highest_outgoing_arg_in_use
;
1063 for (low
= 0; low
< high
; low
++)
1064 if (stack_usage_map
[low
] != 0 || low
>= stack_usage_watermark
)
1067 machine_mode save_mode
;
1073 while (stack_usage_map
[--high
] == 0)
1077 *high_to_save
= high
;
1079 num_to_save
= high
- low
+ 1;
1081 /* If we don't have the required alignment, must do this
1083 scalar_int_mode imode
;
1084 if (int_mode_for_size (num_to_save
* BITS_PER_UNIT
, 1).exists (&imode
)
1085 && (low
& (MIN (GET_MODE_SIZE (imode
),
1086 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)) == 0)
1089 save_mode
= BLKmode
;
1091 if (ARGS_GROW_DOWNWARD
)
1096 addr
= plus_constant (Pmode
, argblock
, delta
);
1097 stack_area
= gen_rtx_MEM (save_mode
, memory_address (save_mode
, addr
));
1099 set_mem_align (stack_area
, PARM_BOUNDARY
);
1100 if (save_mode
== BLKmode
)
1102 save_area
= assign_stack_temp (BLKmode
, num_to_save
);
1103 emit_block_move (validize_mem (save_area
), stack_area
,
1104 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
1108 save_area
= gen_reg_rtx (save_mode
);
1109 emit_move_insn (save_area
, stack_area
);
1119 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
1121 machine_mode save_mode
= GET_MODE (save_area
);
1123 rtx addr
, stack_area
;
1125 if (ARGS_GROW_DOWNWARD
)
1126 delta
= -high_to_save
;
1128 delta
= low_to_save
;
1130 addr
= plus_constant (Pmode
, argblock
, delta
);
1131 stack_area
= gen_rtx_MEM (save_mode
, memory_address (save_mode
, addr
));
1132 set_mem_align (stack_area
, PARM_BOUNDARY
);
1134 if (save_mode
!= BLKmode
)
1135 emit_move_insn (stack_area
, save_area
);
1137 emit_block_move (stack_area
, validize_mem (save_area
),
1138 GEN_INT (high_to_save
- low_to_save
+ 1),
1139 BLOCK_OP_CALL_PARM
);
1141 #endif /* REG_PARM_STACK_SPACE */
1143 /* If any elements in ARGS refer to parameters that are to be passed in
1144 registers, but not in memory, and whose alignment does not permit a
1145 direct copy into registers. Copy the values into a group of pseudos
1146 which we will later copy into the appropriate hard registers.
1148 Pseudos for each unaligned argument will be stored into the array
1149 args[argnum].aligned_regs. The caller is responsible for deallocating
1150 the aligned_regs array if it is nonzero. */
1153 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
1157 for (i
= 0; i
< num_actuals
; i
++)
1158 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
1159 && GET_CODE (args
[i
].reg
) != PARALLEL
1160 && args
[i
].mode
== BLKmode
1161 && MEM_P (args
[i
].value
)
1162 && (MEM_ALIGN (args
[i
].value
)
1163 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
1165 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1166 int endian_correction
= 0;
1168 if (args
[i
].partial
)
1170 gcc_assert (args
[i
].partial
% UNITS_PER_WORD
== 0);
1171 args
[i
].n_aligned_regs
= args
[i
].partial
/ UNITS_PER_WORD
;
1175 args
[i
].n_aligned_regs
1176 = (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
1179 args
[i
].aligned_regs
= XNEWVEC (rtx
, args
[i
].n_aligned_regs
);
1181 /* Structures smaller than a word are normally aligned to the
1182 least significant byte. On a BYTES_BIG_ENDIAN machine,
1183 this means we must skip the empty high order bytes when
1184 calculating the bit offset. */
1185 if (bytes
< UNITS_PER_WORD
1186 #ifdef BLOCK_REG_PADDING
1187 && (BLOCK_REG_PADDING (args
[i
].mode
,
1188 TREE_TYPE (args
[i
].tree_value
), 1)
1194 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
1196 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1198 rtx reg
= gen_reg_rtx (word_mode
);
1199 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
1200 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
1202 args
[i
].aligned_regs
[j
] = reg
;
1203 word
= extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
1204 word_mode
, word_mode
, false, NULL
);
1206 /* There is no need to restrict this code to loading items
1207 in TYPE_ALIGN sized hunks. The bitfield instructions can
1208 load up entire word sized registers efficiently.
1210 ??? This may not be needed anymore.
1211 We use to emit a clobber here but that doesn't let later
1212 passes optimize the instructions we emit. By storing 0 into
1213 the register later passes know the first AND to zero out the
1214 bitfield being set in the register is unnecessary. The store
1215 of 0 will be deleted as will at least the first AND. */
1217 emit_move_insn (reg
, const0_rtx
);
1219 bytes
-= bitsize
/ BITS_PER_UNIT
;
1220 store_bit_field (reg
, bitsize
, endian_correction
, 0, 0,
1221 word_mode
, word
, false);
1226 /* The limit set by -Walloc-larger-than=. */
1227 static GTY(()) tree alloc_object_size_limit
;
1229 /* Initialize ALLOC_OBJECT_SIZE_LIMIT based on the -Walloc-size-larger-than=
1230 setting if the option is specified, or to the maximum object size if it
1231 is not. Return the initialized value. */
1234 alloc_max_size (void)
1236 if (alloc_object_size_limit
)
1237 return alloc_object_size_limit
;
1239 HOST_WIDE_INT limit
= warn_alloc_size_limit
;
1240 if (limit
== HOST_WIDE_INT_MAX
)
1241 limit
= tree_to_shwi (TYPE_MAX_VALUE (ptrdiff_type_node
));
1243 alloc_object_size_limit
= build_int_cst (size_type_node
, limit
);
1245 return alloc_object_size_limit
;
1248 /* Return true when EXP's range can be determined and set RANGE[] to it
1249 after adjusting it if necessary to make EXP a represents a valid size
1250 of object, or a valid size argument to an allocation function declared
1251 with attribute alloc_size (whose argument may be signed), or to a string
1252 manipulation function like memset. When ALLOW_ZERO is true, allow
1253 returning a range of [0, 0] for a size in an anti-range [1, N] where
1254 N > PTRDIFF_MAX. A zero range is a (nearly) invalid argument to
1255 allocation functions like malloc but it is a valid argument to
1256 functions like memset. */
1259 get_size_range (tree exp
, tree range
[2], bool allow_zero
/* = false */)
1261 if (tree_fits_uhwi_p (exp
))
1263 /* EXP is a constant. */
1264 range
[0] = range
[1] = exp
;
1268 tree exptype
= TREE_TYPE (exp
);
1269 bool integral
= INTEGRAL_TYPE_P (exptype
);
1272 enum value_range_kind range_type
;
1275 range_type
= determine_value_range (exp
, &min
, &max
);
1277 range_type
= VR_VARYING
;
1279 if (range_type
== VR_VARYING
)
1283 /* Use the full range of the type of the expression when
1284 no value range information is available. */
1285 range
[0] = TYPE_MIN_VALUE (exptype
);
1286 range
[1] = TYPE_MAX_VALUE (exptype
);
1290 range
[0] = NULL_TREE
;
1291 range
[1] = NULL_TREE
;
1295 unsigned expprec
= TYPE_PRECISION (exptype
);
1297 bool signed_p
= !TYPE_UNSIGNED (exptype
);
1299 if (range_type
== VR_ANTI_RANGE
)
1303 if (wi::les_p (max
, 0))
1305 /* EXP is not in a strictly negative range. That means
1306 it must be in some (not necessarily strictly) positive
1307 range which includes zero. Since in signed to unsigned
1308 conversions negative values end up converted to large
1309 positive values, and otherwise they are not valid sizes,
1310 the resulting range is in both cases [0, TYPE_MAX]. */
1311 min
= wi::zero (expprec
);
1312 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1314 else if (wi::les_p (min
- 1, 0))
1316 /* EXP is not in a negative-positive range. That means EXP
1317 is either negative, or greater than max. Since negative
1318 sizes are invalid make the range [MAX + 1, TYPE_MAX]. */
1320 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1325 min
= wi::zero (expprec
);
1328 else if (wi::eq_p (0, min
- 1))
1330 /* EXP is unsigned and not in the range [1, MAX]. That means
1331 it's either zero or greater than MAX. Even though 0 would
1332 normally be detected by -Walloc-zero, unless ALLOW_ZERO
1333 is true, set the range to [MAX, TYPE_MAX] so that when MAX
1334 is greater than the limit the whole range is diagnosed. */
1336 min
= max
= wi::zero (expprec
);
1340 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1346 min
= wi::zero (expprec
);
1350 range
[0] = wide_int_to_tree (exptype
, min
);
1351 range
[1] = wide_int_to_tree (exptype
, max
);
1356 /* Diagnose a call EXP to function FN decorated with attribute alloc_size
1357 whose argument numbers given by IDX with values given by ARGS exceed
1358 the maximum object size or cause an unsigned oveflow (wrapping) when
1359 multiplied. FN is null when EXP is a call via a function pointer.
1360 When ARGS[0] is null the function does nothing. ARGS[1] may be null
1361 for functions like malloc, and non-null for those like calloc that
1362 are decorated with a two-argument attribute alloc_size. */
1365 maybe_warn_alloc_args_overflow (tree fn
, tree exp
, tree args
[2], int idx
[2])
1367 /* The range each of the (up to) two arguments is known to be in. */
1368 tree argrange
[2][2] = { { NULL_TREE
, NULL_TREE
}, { NULL_TREE
, NULL_TREE
} };
1370 /* Maximum object size set by -Walloc-size-larger-than= or SIZE_MAX / 2. */
1371 tree maxobjsize
= alloc_max_size ();
1373 location_t loc
= EXPR_LOCATION (exp
);
1375 tree fntype
= fn
? TREE_TYPE (fn
) : TREE_TYPE (TREE_TYPE (exp
));
1376 bool warned
= false;
1378 /* Validate each argument individually. */
1379 for (unsigned i
= 0; i
!= 2 && args
[i
]; ++i
)
1381 if (TREE_CODE (args
[i
]) == INTEGER_CST
)
1383 argrange
[i
][0] = args
[i
];
1384 argrange
[i
][1] = args
[i
];
1386 if (tree_int_cst_lt (args
[i
], integer_zero_node
))
1388 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1389 "%Kargument %i value %qE is negative",
1390 exp
, idx
[i
] + 1, args
[i
]);
1392 else if (integer_zerop (args
[i
]))
1394 /* Avoid issuing -Walloc-zero for allocation functions other
1395 than __builtin_alloca that are declared with attribute
1396 returns_nonnull because there's no portability risk. This
1397 avoids warning for such calls to libiberty's xmalloc and
1399 Also avoid issuing the warning for calls to function named
1401 if (fn
&& fndecl_built_in_p (fn
, BUILT_IN_ALLOCA
)
1402 ? IDENTIFIER_LENGTH (DECL_NAME (fn
)) != 6
1403 : !lookup_attribute ("returns_nonnull",
1404 TYPE_ATTRIBUTES (fntype
)))
1405 warned
= warning_at (loc
, OPT_Walloc_zero
,
1406 "%Kargument %i value is zero",
1409 else if (tree_int_cst_lt (maxobjsize
, args
[i
]))
1411 /* G++ emits calls to ::operator new[](SIZE_MAX) in C++98
1412 mode and with -fno-exceptions as a way to indicate array
1413 size overflow. There's no good way to detect C++98 here
1414 so avoid diagnosing these calls for all C++ modes. */
1419 && DECL_IS_OPERATOR_NEW_P (fn
)
1420 && integer_all_onesp (args
[i
]))
1423 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1424 "%Kargument %i value %qE exceeds "
1425 "maximum object size %E",
1426 exp
, idx
[i
] + 1, args
[i
], maxobjsize
);
1429 else if (TREE_CODE (args
[i
]) == SSA_NAME
1430 && get_size_range (args
[i
], argrange
[i
]))
1432 /* Verify that the argument's range is not negative (including
1433 upper bound of zero). */
1434 if (tree_int_cst_lt (argrange
[i
][0], integer_zero_node
)
1435 && tree_int_cst_le (argrange
[i
][1], integer_zero_node
))
1437 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1438 "%Kargument %i range [%E, %E] is negative",
1440 argrange
[i
][0], argrange
[i
][1]);
1442 else if (tree_int_cst_lt (maxobjsize
, argrange
[i
][0]))
1444 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1445 "%Kargument %i range [%E, %E] exceeds "
1446 "maximum object size %E",
1448 argrange
[i
][0], argrange
[i
][1],
1457 /* For a two-argument alloc_size, validate the product of the two
1458 arguments if both of their values or ranges are known. */
1459 if (!warned
&& tree_fits_uhwi_p (argrange
[0][0])
1460 && argrange
[1][0] && tree_fits_uhwi_p (argrange
[1][0])
1461 && !integer_onep (argrange
[0][0])
1462 && !integer_onep (argrange
[1][0]))
1464 /* Check for overflow in the product of a function decorated with
1465 attribute alloc_size (X, Y). */
1466 unsigned szprec
= TYPE_PRECISION (size_type_node
);
1467 wide_int x
= wi::to_wide (argrange
[0][0], szprec
);
1468 wide_int y
= wi::to_wide (argrange
[1][0], szprec
);
1470 wi::overflow_type vflow
;
1471 wide_int prod
= wi::umul (x
, y
, &vflow
);
1474 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1475 "%Kproduct %<%E * %E%> of arguments %i and %i "
1476 "exceeds %<SIZE_MAX%>",
1477 exp
, argrange
[0][0], argrange
[1][0],
1478 idx
[0] + 1, idx
[1] + 1);
1479 else if (wi::ltu_p (wi::to_wide (maxobjsize
, szprec
), prod
))
1480 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1481 "%Kproduct %<%E * %E%> of arguments %i and %i "
1482 "exceeds maximum object size %E",
1483 exp
, argrange
[0][0], argrange
[1][0],
1484 idx
[0] + 1, idx
[1] + 1,
1489 /* Print the full range of each of the two arguments to make
1490 it clear when it is, in fact, in a range and not constant. */
1491 if (argrange
[0][0] != argrange
[0][1])
1492 inform (loc
, "argument %i in the range [%E, %E]",
1493 idx
[0] + 1, argrange
[0][0], argrange
[0][1]);
1494 if (argrange
[1][0] != argrange
[1][1])
1495 inform (loc
, "argument %i in the range [%E, %E]",
1496 idx
[1] + 1, argrange
[1][0], argrange
[1][1]);
1502 location_t fnloc
= DECL_SOURCE_LOCATION (fn
);
1504 if (DECL_IS_BUILTIN (fn
))
1506 "in a call to built-in allocation function %qD", fn
);
1509 "in a call to allocation function %qD declared here", fn
);
1513 /* If EXPR refers to a character array or pointer declared attribute
1514 nonstring return a decl for that array or pointer and set *REF to
1515 the referenced enclosing object or pointer. Otherwise returns
1519 get_attr_nonstring_decl (tree expr
, tree
*ref
)
1522 tree var
= NULL_TREE
;
1523 if (TREE_CODE (decl
) == SSA_NAME
)
1525 gimple
*def
= SSA_NAME_DEF_STMT (decl
);
1527 if (is_gimple_assign (def
))
1529 tree_code code
= gimple_assign_rhs_code (def
);
1530 if (code
== ADDR_EXPR
1531 || code
== COMPONENT_REF
1532 || code
== VAR_DECL
)
1533 decl
= gimple_assign_rhs1 (def
);
1536 var
= SSA_NAME_VAR (decl
);
1539 if (TREE_CODE (decl
) == ADDR_EXPR
)
1540 decl
= TREE_OPERAND (decl
, 0);
1542 /* To simplify calling code, store the referenced DECL regardless of
1543 the attribute determined below, but avoid storing the SSA_NAME_VAR
1544 obtained above (it's not useful for dataflow purposes). */
1548 /* Use the SSA_NAME_VAR that was determined above to see if it's
1549 declared nonstring. Otherwise drill down into the referenced
1553 else if (TREE_CODE (decl
) == ARRAY_REF
)
1554 decl
= TREE_OPERAND (decl
, 0);
1555 else if (TREE_CODE (decl
) == COMPONENT_REF
)
1556 decl
= TREE_OPERAND (decl
, 1);
1557 else if (TREE_CODE (decl
) == MEM_REF
)
1558 return get_attr_nonstring_decl (TREE_OPERAND (decl
, 0), ref
);
1561 && lookup_attribute ("nonstring", DECL_ATTRIBUTES (decl
)))
1567 /* Warn about passing a non-string array/pointer to a function that
1568 expects a nul-terminated string argument. */
1571 maybe_warn_nonstring_arg (tree fndecl
, tree exp
)
1573 if (!fndecl
|| !fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
1576 if (TREE_NO_WARNING (exp
) || !warn_stringop_overflow
)
1579 /* Avoid clearly invalid calls (more checking done below). */
1580 unsigned nargs
= call_expr_nargs (exp
);
1584 /* The bound argument to a bounded string function like strncpy. */
1585 tree bound
= NULL_TREE
;
1587 /* The longest known or possible string argument to one of the comparison
1588 functions. If the length is less than the bound it is used instead.
1589 Since the length is only used for warning and not for code generation
1590 disable strict mode in the calls to get_range_strlen below. */
1591 tree maxlen
= NULL_TREE
;
1593 /* It's safe to call "bounded" string functions with a non-string
1594 argument since the functions provide an explicit bound for this
1595 purpose. The exception is strncat where the bound may refer to
1596 either the destination or the source. */
1597 int fncode
= DECL_FUNCTION_CODE (fndecl
);
1600 case BUILT_IN_STRCMP
:
1601 case BUILT_IN_STRNCMP
:
1602 case BUILT_IN_STRNCASECMP
:
1604 /* For these, if one argument refers to one or more of a set
1605 of string constants or arrays of known size, determine
1606 the range of their known or possible lengths and use it
1607 conservatively as the bound for the unbounded function,
1608 and to adjust the range of the bound of the bounded ones. */
1609 for (unsigned argno
= 0;
1610 argno
< MIN (nargs
, 2)
1611 && !(maxlen
&& TREE_CODE (maxlen
) == INTEGER_CST
); argno
++)
1613 tree arg
= CALL_EXPR_ARG (exp
, argno
);
1614 if (!get_attr_nonstring_decl (arg
))
1616 c_strlen_data lendata
= { };
1617 /* Set MAXBOUND to an arbitrary non-null non-integer
1618 node as a request to have it set to the length of
1619 the longest string in a PHI. */
1620 lendata
.maxbound
= arg
;
1621 get_range_strlen (arg
, &lendata
, /* eltsize = */ 1);
1622 maxlen
= lendata
.maxbound
;
1628 case BUILT_IN_STRNCAT
:
1629 case BUILT_IN_STPNCPY
:
1630 case BUILT_IN_STRNCPY
:
1632 bound
= CALL_EXPR_ARG (exp
, 2);
1635 case BUILT_IN_STRNDUP
:
1637 bound
= CALL_EXPR_ARG (exp
, 1);
1640 case BUILT_IN_STRNLEN
:
1642 tree arg
= CALL_EXPR_ARG (exp
, 0);
1643 if (!get_attr_nonstring_decl (arg
))
1645 c_strlen_data lendata
= { };
1646 /* Set MAXBOUND to an arbitrary non-null non-integer
1647 node as a request to have it set to the length of
1648 the longest string in a PHI. */
1649 lendata
.maxbound
= arg
;
1650 get_range_strlen (arg
, &lendata
, /* eltsize = */ 1);
1651 maxlen
= lendata
.maxbound
;
1654 bound
= CALL_EXPR_ARG (exp
, 1);
1662 /* Determine the range of the bound argument (if specified). */
1663 tree bndrng
[2] = { NULL_TREE
, NULL_TREE
};
1667 get_size_range (bound
, bndrng
);
1670 location_t loc
= EXPR_LOCATION (exp
);
1674 /* Diagnose excessive bound prior the adjustment below and
1675 regardless of attribute nonstring. */
1676 tree maxobjsize
= max_object_size ();
1677 if (tree_int_cst_lt (maxobjsize
, bndrng
[0]))
1679 if (tree_int_cst_equal (bndrng
[0], bndrng
[1]))
1680 warning_at (loc
, OPT_Wstringop_overflow_
,
1681 "%K%qD specified bound %E "
1682 "exceeds maximum object size %E",
1683 exp
, fndecl
, bndrng
[0], maxobjsize
);
1685 warning_at (loc
, OPT_Wstringop_overflow_
,
1686 "%K%qD specified bound [%E, %E] "
1687 "exceeds maximum object size %E",
1688 exp
, fndecl
, bndrng
[0], bndrng
[1], maxobjsize
);
1693 if (maxlen
&& !integer_all_onesp (maxlen
))
1695 /* Add one for the nul. */
1696 maxlen
= const_binop (PLUS_EXPR
, TREE_TYPE (maxlen
), maxlen
,
1701 /* Conservatively use the upper bound of the lengths for
1702 both the lower and the upper bound of the operation. */
1705 bound
= void_type_node
;
1709 /* Replace the bound on the operation with the upper bound
1710 of the length of the string if the latter is smaller. */
1711 if (tree_int_cst_lt (maxlen
, bndrng
[0]))
1713 else if (tree_int_cst_lt (maxlen
, bndrng
[1]))
1718 /* Iterate over the built-in function's formal arguments and check
1719 each const char* against the actual argument. If the actual
1720 argument is declared attribute non-string issue a warning unless
1721 the argument's maximum length is bounded. */
1722 function_args_iterator it
;
1723 function_args_iter_init (&it
, TREE_TYPE (fndecl
));
1725 for (unsigned argno
= 0; ; ++argno
, function_args_iter_next (&it
))
1727 /* Avoid iterating past the declared argument in a call
1728 to function declared without a prototype. */
1732 tree argtype
= function_args_iter_cond (&it
);
1736 if (TREE_CODE (argtype
) != POINTER_TYPE
)
1739 argtype
= TREE_TYPE (argtype
);
1741 if (TREE_CODE (argtype
) != INTEGER_TYPE
1742 || !TYPE_READONLY (argtype
))
1745 argtype
= TYPE_MAIN_VARIANT (argtype
);
1746 if (argtype
!= char_type_node
)
1749 tree callarg
= CALL_EXPR_ARG (exp
, argno
);
1750 if (TREE_CODE (callarg
) == ADDR_EXPR
)
1751 callarg
= TREE_OPERAND (callarg
, 0);
1753 /* See if the destination is declared with attribute "nonstring". */
1754 tree decl
= get_attr_nonstring_decl (callarg
);
1758 /* The maximum number of array elements accessed. */
1759 offset_int wibnd
= 0;
1761 if (argno
&& fncode
== BUILT_IN_STRNCAT
)
1763 /* See if the bound in strncat is derived from the length
1764 of the strlen of the destination (as it's expected to be).
1765 If so, reset BOUND and FNCODE to trigger a warning. */
1766 tree dstarg
= CALL_EXPR_ARG (exp
, 0);
1767 if (is_strlen_related_p (dstarg
, bound
))
1769 /* The bound applies to the destination, not to the source,
1770 so reset these to trigger a warning without mentioning
1776 /* Use the upper bound of the range for strncat. */
1777 wibnd
= wi::to_offset (bndrng
[1]);
1780 /* Use the lower bound of the range for functions other than
1782 wibnd
= wi::to_offset (bndrng
[0]);
1784 /* Determine the size of the argument array if it is one. */
1785 offset_int asize
= wibnd
;
1786 bool known_size
= false;
1787 tree type
= TREE_TYPE (decl
);
1789 /* Determine the array size. For arrays of unknown bound and
1790 pointers reset BOUND to trigger the appropriate warning. */
1791 if (TREE_CODE (type
) == ARRAY_TYPE
)
1793 if (tree arrbnd
= TYPE_DOMAIN (type
))
1795 if ((arrbnd
= TYPE_MAX_VALUE (arrbnd
)))
1797 asize
= wi::to_offset (arrbnd
) + 1;
1801 else if (bound
== void_type_node
)
1804 else if (bound
== void_type_node
)
1807 /* In a call to strncat with a bound in a range whose lower but
1808 not upper bound is less than the array size, reset ASIZE to
1809 be the same as the bound and the other variable to trigger
1810 the apprpriate warning below. */
1811 if (fncode
== BUILT_IN_STRNCAT
1812 && bndrng
[0] != bndrng
[1]
1813 && wi::ltu_p (wi::to_offset (bndrng
[0]), asize
)
1815 || wi::ltu_p (asize
, wibnd
)))
1822 bool warned
= false;
1824 auto_diagnostic_group d
;
1825 if (wi::ltu_p (asize
, wibnd
))
1827 if (bndrng
[0] == bndrng
[1])
1828 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1829 "%qD argument %i declared attribute "
1830 "%<nonstring%> is smaller than the specified "
1832 fndecl
, argno
+ 1, wibnd
.to_uhwi ());
1833 else if (wi::ltu_p (asize
, wi::to_offset (bndrng
[0])))
1834 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1835 "%qD argument %i declared attribute "
1836 "%<nonstring%> is smaller than "
1837 "the specified bound [%E, %E]",
1838 fndecl
, argno
+ 1, bndrng
[0], bndrng
[1]);
1840 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1841 "%qD argument %i declared attribute "
1842 "%<nonstring%> may be smaller than "
1843 "the specified bound [%E, %E]",
1844 fndecl
, argno
+ 1, bndrng
[0], bndrng
[1]);
1846 else if (fncode
== BUILT_IN_STRNCAT
)
1847 ; /* Avoid warning for calls to strncat() when the bound
1848 is equal to the size of the non-string argument. */
1850 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1851 "%qD argument %i declared attribute %<nonstring%>",
1855 inform (DECL_SOURCE_LOCATION (decl
),
1856 "argument %qD declared here", decl
);
1860 /* Issue an error if CALL_EXPR was flagged as requiring
1861 tall-call optimization. */
1864 maybe_complain_about_tail_call (tree call_expr
, const char *reason
)
1866 gcc_assert (TREE_CODE (call_expr
) == CALL_EXPR
);
1867 if (!CALL_EXPR_MUST_TAIL_CALL (call_expr
))
1870 error_at (EXPR_LOCATION (call_expr
), "cannot tail-call: %s", reason
);
1873 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1876 NUM_ACTUALS is the total number of parameters.
1878 N_NAMED_ARGS is the total number of named arguments.
1880 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1883 FNDECL is the tree code for the target of this call (if known)
1885 ARGS_SO_FAR holds state needed by the target to know where to place
1888 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1889 for arguments which are passed in registers.
1891 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1892 and may be modified by this routine.
1894 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1895 flags which may be modified by this routine.
1897 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1898 that requires allocation of stack space.
1900 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1901 the thunked-to function. */
1904 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
1905 struct arg_data
*args
,
1906 struct args_size
*args_size
,
1907 int n_named_args ATTRIBUTE_UNUSED
,
1908 tree exp
, tree struct_value_addr_value
,
1909 tree fndecl
, tree fntype
,
1910 cumulative_args_t args_so_far
,
1911 int reg_parm_stack_space
,
1912 rtx
*old_stack_level
,
1913 poly_int64_pod
*old_pending_adj
,
1914 int *must_preallocate
, int *ecf_flags
,
1915 bool *may_tailcall
, bool call_from_thunk_p
)
1917 CUMULATIVE_ARGS
*args_so_far_pnt
= get_cumulative_args (args_so_far
);
1918 location_t loc
= EXPR_LOCATION (exp
);
1920 /* Count arg position in order args appear. */
1925 args_size
->constant
= 0;
1928 bitmap_obstack_initialize (NULL
);
1930 /* In this loop, we consider args in the order they are written.
1931 We fill up ARGS from the back. */
1933 i
= num_actuals
- 1;
1936 call_expr_arg_iterator iter
;
1938 bitmap slots
= NULL
;
1940 if (struct_value_addr_value
)
1942 args
[j
].tree_value
= struct_value_addr_value
;
1946 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
1948 tree argtype
= TREE_TYPE (arg
);
1950 if (targetm
.calls
.split_complex_arg
1952 && TREE_CODE (argtype
) == COMPLEX_TYPE
1953 && targetm
.calls
.split_complex_arg (argtype
))
1955 tree subtype
= TREE_TYPE (argtype
);
1956 args
[j
].tree_value
= build1 (REALPART_EXPR
, subtype
, arg
);
1958 args
[j
].tree_value
= build1 (IMAGPART_EXPR
, subtype
, arg
);
1961 args
[j
].tree_value
= arg
;
1967 BITMAP_FREE (slots
);
1970 bitmap_obstack_release (NULL
);
1972 /* Extract attribute alloc_size from the type of the called expression
1973 (which could be a function or a function pointer) and if set, store
1974 the indices of the corresponding arguments in ALLOC_IDX, and then
1975 the actual argument(s) at those indices in ALLOC_ARGS. */
1976 int alloc_idx
[2] = { -1, -1 };
1977 if (tree alloc_size
= lookup_attribute ("alloc_size",
1978 TYPE_ATTRIBUTES (fntype
)))
1980 tree args
= TREE_VALUE (alloc_size
);
1981 alloc_idx
[0] = TREE_INT_CST_LOW (TREE_VALUE (args
)) - 1;
1982 if (TREE_CHAIN (args
))
1983 alloc_idx
[1] = TREE_INT_CST_LOW (TREE_VALUE (TREE_CHAIN (args
))) - 1;
1986 /* Array for up to the two attribute alloc_size arguments. */
1987 tree alloc_args
[] = { NULL_TREE
, NULL_TREE
};
1989 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1990 for (argpos
= 0; argpos
< num_actuals
; i
--, argpos
++)
1992 tree type
= TREE_TYPE (args
[i
].tree_value
);
1995 /* Replace erroneous argument with constant zero. */
1996 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1997 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1999 /* If TYPE is a transparent union or record, pass things the way
2000 we would pass the first field of the union or record. We have
2001 already verified that the modes are the same. */
2002 if (RECORD_OR_UNION_TYPE_P (type
) && TYPE_TRANSPARENT_AGGR (type
))
2003 type
= TREE_TYPE (first_field (type
));
2005 /* Decide where to pass this arg.
2007 args[i].reg is nonzero if all or part is passed in registers.
2009 args[i].partial is nonzero if part but not all is passed in registers,
2010 and the exact value says how many bytes are passed in registers.
2012 args[i].pass_on_stack is nonzero if the argument must at least be
2013 computed on the stack. It may then be loaded back into registers
2014 if args[i].reg is nonzero.
2016 These decisions are driven by the FUNCTION_... macros and must agree
2017 with those made by function.c. */
2019 /* See if this argument should be passed by invisible reference. */
2020 function_arg_info
arg (type
, argpos
< n_named_args
);
2021 if (pass_by_reference (args_so_far_pnt
, arg
))
2024 tree base
= NULL_TREE
;
2026 callee_copies
= reference_callee_copied (args_so_far_pnt
, arg
);
2028 /* If we're compiling a thunk, pass through invisible references
2029 instead of making a copy. */
2030 if (call_from_thunk_p
2032 && !TREE_ADDRESSABLE (type
)
2033 && (base
= get_base_address (args
[i
].tree_value
))
2034 && TREE_CODE (base
) != SSA_NAME
2035 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
)))))
2037 /* We may have turned the parameter value into an SSA name.
2038 Go back to the original parameter so we can take the
2040 if (TREE_CODE (args
[i
].tree_value
) == SSA_NAME
)
2042 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args
[i
].tree_value
));
2043 args
[i
].tree_value
= SSA_NAME_VAR (args
[i
].tree_value
);
2044 gcc_assert (TREE_CODE (args
[i
].tree_value
) == PARM_DECL
);
2046 /* Argument setup code may have copied the value to register. We
2047 revert that optimization now because the tail call code must
2048 use the original location. */
2049 if (TREE_CODE (args
[i
].tree_value
) == PARM_DECL
2050 && !MEM_P (DECL_RTL (args
[i
].tree_value
))
2051 && DECL_INCOMING_RTL (args
[i
].tree_value
)
2052 && MEM_P (DECL_INCOMING_RTL (args
[i
].tree_value
)))
2053 set_decl_rtl (args
[i
].tree_value
,
2054 DECL_INCOMING_RTL (args
[i
].tree_value
));
2056 mark_addressable (args
[i
].tree_value
);
2058 /* We can't use sibcalls if a callee-copied argument is
2059 stored in the current function's frame. */
2060 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
2062 *may_tailcall
= false;
2063 maybe_complain_about_tail_call (exp
,
2064 "a callee-copied argument is"
2065 " stored in the current"
2066 " function's frame");
2069 args
[i
].tree_value
= build_fold_addr_expr_loc (loc
,
2070 args
[i
].tree_value
);
2071 type
= TREE_TYPE (args
[i
].tree_value
);
2073 if (*ecf_flags
& ECF_CONST
)
2074 *ecf_flags
&= ~(ECF_CONST
| ECF_LOOPING_CONST_OR_PURE
);
2078 /* We make a copy of the object and pass the address to the
2079 function being called. */
2082 if (!COMPLETE_TYPE_P (type
)
2083 || TREE_CODE (TYPE_SIZE_UNIT (type
)) != INTEGER_CST
2084 || (flag_stack_check
== GENERIC_STACK_CHECK
2085 && compare_tree_int (TYPE_SIZE_UNIT (type
),
2086 STACK_CHECK_MAX_VAR_SIZE
) > 0))
2088 /* This is a variable-sized object. Make space on the stack
2090 rtx size_rtx
= expr_size (args
[i
].tree_value
);
2092 if (*old_stack_level
== 0)
2094 emit_stack_save (SAVE_BLOCK
, old_stack_level
);
2095 *old_pending_adj
= pending_stack_adjust
;
2096 pending_stack_adjust
= 0;
2099 /* We can pass TRUE as the 4th argument because we just
2100 saved the stack pointer and will restore it right after
2102 copy
= allocate_dynamic_stack_space (size_rtx
,
2105 max_int_size_in_bytes
2108 copy
= gen_rtx_MEM (BLKmode
, copy
);
2109 set_mem_attributes (copy
, type
, 1);
2112 copy
= assign_temp (type
, 1, 0);
2114 store_expr (args
[i
].tree_value
, copy
, 0, false, false);
2116 /* Just change the const function to pure and then let
2117 the next test clear the pure based on
2119 if (*ecf_flags
& ECF_CONST
)
2121 *ecf_flags
&= ~ECF_CONST
;
2122 *ecf_flags
|= ECF_PURE
;
2125 if (!callee_copies
&& *ecf_flags
& ECF_PURE
)
2126 *ecf_flags
&= ~(ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
2129 = build_fold_addr_expr_loc (loc
, make_tree (type
, copy
));
2130 type
= TREE_TYPE (args
[i
].tree_value
);
2131 *may_tailcall
= false;
2132 maybe_complain_about_tail_call (exp
,
2133 "argument must be passed"
2136 arg
.pass_by_reference
= true;
2139 unsignedp
= TYPE_UNSIGNED (type
);
2142 = promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
2143 fndecl
? TREE_TYPE (fndecl
) : fntype
, 0);
2145 args
[i
].unsignedp
= unsignedp
;
2146 args
[i
].mode
= arg
.mode
;
2148 targetm
.calls
.warn_parameter_passing_abi (args_so_far
, type
);
2150 args
[i
].reg
= targetm
.calls
.function_arg (args_so_far
, arg
);
2152 if (args
[i
].reg
&& CONST_INT_P (args
[i
].reg
))
2155 /* If this is a sibling call and the machine has register windows, the
2156 register window has to be unwinded before calling the routine, so
2157 arguments have to go into the incoming registers. */
2158 if (targetm
.calls
.function_incoming_arg
!= targetm
.calls
.function_arg
)
2159 args
[i
].tail_call_reg
2160 = targetm
.calls
.function_incoming_arg (args_so_far
, arg
);
2162 args
[i
].tail_call_reg
= args
[i
].reg
;
2165 args
[i
].partial
= targetm
.calls
.arg_partial_bytes (args_so_far
, arg
);
2167 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (arg
);
2169 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
2170 it means that we are to pass this arg in the register(s) designated
2171 by the PARALLEL, but also to pass it in the stack. */
2172 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
2173 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
2174 args
[i
].pass_on_stack
= 1;
2176 /* If this is an addressable type, we must preallocate the stack
2177 since we must evaluate the object into its final location.
2179 If this is to be passed in both registers and the stack, it is simpler
2181 if (TREE_ADDRESSABLE (type
)
2182 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
2183 *must_preallocate
= 1;
2185 /* Compute the stack-size of this argument. */
2186 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
2187 || reg_parm_stack_space
> 0
2188 || args
[i
].pass_on_stack
)
2189 locate_and_pad_parm (arg
.mode
, type
,
2190 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2195 reg_parm_stack_space
,
2196 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
2197 fndecl
, args_size
, &args
[i
].locate
);
2198 #ifdef BLOCK_REG_PADDING
2200 /* The argument is passed entirely in registers. See at which
2201 end it should be padded. */
2202 args
[i
].locate
.where_pad
=
2203 BLOCK_REG_PADDING (arg
.mode
, type
,
2204 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
2207 /* Update ARGS_SIZE, the total stack space for args so far. */
2209 args_size
->constant
+= args
[i
].locate
.size
.constant
;
2210 if (args
[i
].locate
.size
.var
)
2211 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
2213 /* Increment ARGS_SO_FAR, which has info about which arg-registers
2214 have been used, etc. */
2216 /* ??? Traditionally we've passed TYPE_MODE here, instead of the
2217 promoted_mode used for function_arg above. However, the
2218 corresponding handling of incoming arguments in function.c
2219 does pass the promoted mode. */
2220 arg
.mode
= TYPE_MODE (type
);
2221 targetm
.calls
.function_arg_advance (args_so_far
, arg
);
2223 /* Store argument values for functions decorated with attribute
2225 if (argpos
== alloc_idx
[0])
2226 alloc_args
[0] = args
[i
].tree_value
;
2227 else if (argpos
== alloc_idx
[1])
2228 alloc_args
[1] = args
[i
].tree_value
;
2233 /* Check the arguments of functions decorated with attribute
2235 maybe_warn_alloc_args_overflow (fndecl
, exp
, alloc_args
, alloc_idx
);
2238 /* Detect passing non-string arguments to functions expecting
2239 nul-terminated strings. */
2240 maybe_warn_nonstring_arg (fndecl
, exp
);
2243 /* Update ARGS_SIZE to contain the total size for the argument block.
2244 Return the original constant component of the argument block's size.
2246 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
2247 for arguments passed in registers. */
2250 compute_argument_block_size (int reg_parm_stack_space
,
2251 struct args_size
*args_size
,
2252 tree fndecl ATTRIBUTE_UNUSED
,
2253 tree fntype ATTRIBUTE_UNUSED
,
2254 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
2256 poly_int64 unadjusted_args_size
= args_size
->constant
;
2258 /* For accumulate outgoing args mode we don't need to align, since the frame
2259 will be already aligned. Align to STACK_BOUNDARY in order to prevent
2260 backends from generating misaligned frame sizes. */
2261 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
2262 preferred_stack_boundary
= STACK_BOUNDARY
;
2264 /* Compute the actual size of the argument block required. The variable
2265 and constant sizes must be combined, the size may have to be rounded,
2266 and there may be a minimum required size. */
2270 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
2271 args_size
->constant
= 0;
2273 preferred_stack_boundary
/= BITS_PER_UNIT
;
2274 if (preferred_stack_boundary
> 1)
2276 /* We don't handle this case yet. To handle it correctly we have
2277 to add the delta, round and subtract the delta.
2278 Currently no machine description requires this support. */
2279 gcc_assert (multiple_p (stack_pointer_delta
,
2280 preferred_stack_boundary
));
2281 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
2284 if (reg_parm_stack_space
> 0)
2287 = size_binop (MAX_EXPR
, args_size
->var
,
2288 ssize_int (reg_parm_stack_space
));
2290 /* The area corresponding to register parameters is not to count in
2291 the size of the block we need. So make the adjustment. */
2292 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2294 = size_binop (MINUS_EXPR
, args_size
->var
,
2295 ssize_int (reg_parm_stack_space
));
2300 preferred_stack_boundary
/= BITS_PER_UNIT
;
2301 if (preferred_stack_boundary
< 1)
2302 preferred_stack_boundary
= 1;
2303 args_size
->constant
= (aligned_upper_bound (args_size
->constant
2304 + stack_pointer_delta
,
2305 preferred_stack_boundary
)
2306 - stack_pointer_delta
);
2308 args_size
->constant
= upper_bound (args_size
->constant
,
2309 reg_parm_stack_space
);
2311 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2312 args_size
->constant
-= reg_parm_stack_space
;
2314 return unadjusted_args_size
;
2317 /* Precompute parameters as needed for a function call.
2319 FLAGS is mask of ECF_* constants.
2321 NUM_ACTUALS is the number of arguments.
2323 ARGS is an array containing information for each argument; this
2324 routine fills in the INITIAL_VALUE and VALUE fields for each
2325 precomputed argument. */
2328 precompute_arguments (int num_actuals
, struct arg_data
*args
)
2332 /* If this is a libcall, then precompute all arguments so that we do not
2333 get extraneous instructions emitted as part of the libcall sequence. */
2335 /* If we preallocated the stack space, and some arguments must be passed
2336 on the stack, then we must precompute any parameter which contains a
2337 function call which will store arguments on the stack.
2338 Otherwise, evaluating the parameter may clobber previous parameters
2339 which have already been stored into the stack. (we have code to avoid
2340 such case by saving the outgoing stack arguments, but it results in
2342 if (!ACCUMULATE_OUTGOING_ARGS
)
2345 for (i
= 0; i
< num_actuals
; i
++)
2350 if (TREE_CODE (args
[i
].tree_value
) != CALL_EXPR
)
2353 /* If this is an addressable type, we cannot pre-evaluate it. */
2354 type
= TREE_TYPE (args
[i
].tree_value
);
2355 gcc_assert (!TREE_ADDRESSABLE (type
));
2357 args
[i
].initial_value
= args
[i
].value
2358 = expand_normal (args
[i
].tree_value
);
2360 mode
= TYPE_MODE (type
);
2361 if (mode
!= args
[i
].mode
)
2363 int unsignedp
= args
[i
].unsignedp
;
2365 = convert_modes (args
[i
].mode
, mode
,
2366 args
[i
].value
, args
[i
].unsignedp
);
2368 /* CSE will replace this only if it contains args[i].value
2369 pseudo, so convert it down to the declared mode using
2371 if (REG_P (args
[i
].value
)
2372 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
2373 && promote_mode (type
, mode
, &unsignedp
) != args
[i
].mode
)
2375 args
[i
].initial_value
2376 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
2377 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
2378 SUBREG_PROMOTED_SET (args
[i
].initial_value
, args
[i
].unsignedp
);
2384 /* Given the current state of MUST_PREALLOCATE and information about
2385 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
2386 compute and return the final value for MUST_PREALLOCATE. */
2389 finalize_must_preallocate (int must_preallocate
, int num_actuals
,
2390 struct arg_data
*args
, struct args_size
*args_size
)
2392 /* See if we have or want to preallocate stack space.
2394 If we would have to push a partially-in-regs parm
2395 before other stack parms, preallocate stack space instead.
2397 If the size of some parm is not a multiple of the required stack
2398 alignment, we must preallocate.
2400 If the total size of arguments that would otherwise create a copy in
2401 a temporary (such as a CALL) is more than half the total argument list
2402 size, preallocation is faster.
2404 Another reason to preallocate is if we have a machine (like the m88k)
2405 where stack alignment is required to be maintained between every
2406 pair of insns, not just when the call is made. However, we assume here
2407 that such machines either do not have push insns (and hence preallocation
2408 would occur anyway) or the problem is taken care of with
2411 if (! must_preallocate
)
2413 int partial_seen
= 0;
2414 poly_int64 copy_to_evaluate_size
= 0;
2417 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
2419 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
2421 else if (partial_seen
&& args
[i
].reg
== 0)
2422 must_preallocate
= 1;
2424 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
2425 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
2426 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
2427 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
2428 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
2429 copy_to_evaluate_size
2430 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
2433 if (maybe_ne (args_size
->constant
, 0)
2434 && maybe_ge (copy_to_evaluate_size
* 2, args_size
->constant
))
2435 must_preallocate
= 1;
2437 return must_preallocate
;
2440 /* If we preallocated stack space, compute the address of each argument
2441 and store it into the ARGS array.
2443 We need not ensure it is a valid memory address here; it will be
2444 validized when it is used.
2446 ARGBLOCK is an rtx for the address of the outgoing arguments. */
2449 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
2453 rtx arg_reg
= argblock
;
2455 poly_int64 arg_offset
= 0;
2457 if (GET_CODE (argblock
) == PLUS
)
2459 arg_reg
= XEXP (argblock
, 0);
2460 arg_offset
= rtx_to_poly_int64 (XEXP (argblock
, 1));
2463 for (i
= 0; i
< num_actuals
; i
++)
2465 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
2466 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
2468 unsigned int align
, boundary
;
2469 poly_uint64 units_on_stack
= 0;
2470 machine_mode partial_mode
= VOIDmode
;
2472 /* Skip this parm if it will not be passed on the stack. */
2473 if (! args
[i
].pass_on_stack
2475 && args
[i
].partial
== 0)
2478 if (TYPE_EMPTY_P (TREE_TYPE (args
[i
].tree_value
)))
2481 addr
= simplify_gen_binary (PLUS
, Pmode
, arg_reg
, offset
);
2482 addr
= plus_constant (Pmode
, addr
, arg_offset
);
2484 if (args
[i
].partial
!= 0)
2486 /* Only part of the parameter is being passed on the stack.
2487 Generate a simple memory reference of the correct size. */
2488 units_on_stack
= args
[i
].locate
.size
.constant
;
2489 poly_uint64 bits_on_stack
= units_on_stack
* BITS_PER_UNIT
;
2490 partial_mode
= int_mode_for_size (bits_on_stack
, 1).else_blk ();
2491 args
[i
].stack
= gen_rtx_MEM (partial_mode
, addr
);
2492 set_mem_size (args
[i
].stack
, units_on_stack
);
2496 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
2497 set_mem_attributes (args
[i
].stack
,
2498 TREE_TYPE (args
[i
].tree_value
), 1);
2500 align
= BITS_PER_UNIT
;
2501 boundary
= args
[i
].locate
.boundary
;
2502 poly_int64 offset_val
;
2503 if (args
[i
].locate
.where_pad
!= PAD_DOWNWARD
)
2505 else if (poly_int_rtx_p (offset
, &offset_val
))
2507 align
= least_bit_hwi (boundary
);
2508 unsigned int offset_align
2509 = known_alignment (offset_val
) * BITS_PER_UNIT
;
2510 if (offset_align
!= 0)
2511 align
= MIN (align
, offset_align
);
2513 set_mem_align (args
[i
].stack
, align
);
2515 addr
= simplify_gen_binary (PLUS
, Pmode
, arg_reg
, slot_offset
);
2516 addr
= plus_constant (Pmode
, addr
, arg_offset
);
2518 if (args
[i
].partial
!= 0)
2520 /* Only part of the parameter is being passed on the stack.
2521 Generate a simple memory reference of the correct size.
2523 args
[i
].stack_slot
= gen_rtx_MEM (partial_mode
, addr
);
2524 set_mem_size (args
[i
].stack_slot
, units_on_stack
);
2528 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
2529 set_mem_attributes (args
[i
].stack_slot
,
2530 TREE_TYPE (args
[i
].tree_value
), 1);
2532 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
2534 /* Function incoming arguments may overlap with sibling call
2535 outgoing arguments and we cannot allow reordering of reads
2536 from function arguments with stores to outgoing arguments
2537 of sibling calls. */
2538 set_mem_alias_set (args
[i
].stack
, 0);
2539 set_mem_alias_set (args
[i
].stack_slot
, 0);
2544 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
2545 in a call instruction.
2547 FNDECL is the tree node for the target function. For an indirect call
2548 FNDECL will be NULL_TREE.
2550 ADDR is the operand 0 of CALL_EXPR for this call. */
2553 rtx_for_function_call (tree fndecl
, tree addr
)
2557 /* Get the function to call, in the form of RTL. */
2560 if (!TREE_USED (fndecl
) && fndecl
!= current_function_decl
)
2561 TREE_USED (fndecl
) = 1;
2563 /* Get a SYMBOL_REF rtx for the function address. */
2564 funexp
= XEXP (DECL_RTL (fndecl
), 0);
2567 /* Generate an rtx (probably a pseudo-register) for the address. */
2570 funexp
= expand_normal (addr
);
2571 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
2576 /* Return the static chain for this function, if any. */
2579 rtx_for_static_chain (const_tree fndecl_or_type
, bool incoming_p
)
2581 if (DECL_P (fndecl_or_type
) && !DECL_STATIC_CHAIN (fndecl_or_type
))
2584 return targetm
.calls
.static_chain (fndecl_or_type
, incoming_p
);
2587 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
2590 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
2591 or NULL_RTX if none has been scanned yet. */
2592 rtx_insn
*scan_start
;
2593 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
2594 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
2595 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
2596 with fixed offset, or PC if this is with variable or unknown offset. */
2598 } internal_arg_pointer_exp_state
;
2600 static rtx
internal_arg_pointer_based_exp (const_rtx
, bool);
2602 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
2603 the tail call sequence, starting with first insn that hasn't been
2604 scanned yet, and note for each pseudo on the LHS whether it is based
2605 on crtl->args.internal_arg_pointer or not, and what offset from that
2606 that pointer it has. */
2609 internal_arg_pointer_based_exp_scan (void)
2611 rtx_insn
*insn
, *scan_start
= internal_arg_pointer_exp_state
.scan_start
;
2613 if (scan_start
== NULL_RTX
)
2614 insn
= get_insns ();
2616 insn
= NEXT_INSN (scan_start
);
2620 rtx set
= single_set (insn
);
2621 if (set
&& REG_P (SET_DEST (set
)) && !HARD_REGISTER_P (SET_DEST (set
)))
2624 unsigned int idx
= REGNO (SET_DEST (set
)) - FIRST_PSEUDO_REGISTER
;
2625 /* Punt on pseudos set multiple times. */
2626 if (idx
< internal_arg_pointer_exp_state
.cache
.length ()
2627 && (internal_arg_pointer_exp_state
.cache
[idx
]
2631 val
= internal_arg_pointer_based_exp (SET_SRC (set
), false);
2632 if (val
!= NULL_RTX
)
2634 if (idx
>= internal_arg_pointer_exp_state
.cache
.length ())
2635 internal_arg_pointer_exp_state
.cache
2636 .safe_grow_cleared (idx
+ 1);
2637 internal_arg_pointer_exp_state
.cache
[idx
] = val
;
2640 if (NEXT_INSN (insn
) == NULL_RTX
)
2642 insn
= NEXT_INSN (insn
);
2645 internal_arg_pointer_exp_state
.scan_start
= scan_start
;
2648 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
2649 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
2650 it with fixed offset, or PC if this is with variable or unknown offset.
2651 TOPLEVEL is true if the function is invoked at the topmost level. */
2654 internal_arg_pointer_based_exp (const_rtx rtl
, bool toplevel
)
2656 if (CONSTANT_P (rtl
))
2659 if (rtl
== crtl
->args
.internal_arg_pointer
)
2662 if (REG_P (rtl
) && HARD_REGISTER_P (rtl
))
2666 if (GET_CODE (rtl
) == PLUS
&& poly_int_rtx_p (XEXP (rtl
, 1), &offset
))
2668 rtx val
= internal_arg_pointer_based_exp (XEXP (rtl
, 0), toplevel
);
2669 if (val
== NULL_RTX
|| val
== pc_rtx
)
2671 return plus_constant (Pmode
, val
, offset
);
2674 /* When called at the topmost level, scan pseudo assignments in between the
2675 last scanned instruction in the tail call sequence and the latest insn
2676 in that sequence. */
2678 internal_arg_pointer_based_exp_scan ();
2682 unsigned int idx
= REGNO (rtl
) - FIRST_PSEUDO_REGISTER
;
2683 if (idx
< internal_arg_pointer_exp_state
.cache
.length ())
2684 return internal_arg_pointer_exp_state
.cache
[idx
];
2689 subrtx_iterator::array_type array
;
2690 FOR_EACH_SUBRTX (iter
, array
, rtl
, NONCONST
)
2692 const_rtx x
= *iter
;
2693 if (REG_P (x
) && internal_arg_pointer_based_exp (x
, false) != NULL_RTX
)
2696 iter
.skip_subrtxes ();
2702 /* Return true if SIZE bytes starting from address ADDR might overlap an
2703 already-clobbered argument area. This function is used to determine
2704 if we should give up a sibcall. */
2707 mem_might_overlap_already_clobbered_arg_p (rtx addr
, poly_uint64 size
)
2710 unsigned HOST_WIDE_INT start
, end
;
2713 if (bitmap_empty_p (stored_args_map
)
2714 && stored_args_watermark
== HOST_WIDE_INT_M1U
)
2716 val
= internal_arg_pointer_based_exp (addr
, true);
2717 if (val
== NULL_RTX
)
2719 else if (!poly_int_rtx_p (val
, &i
))
2722 if (known_eq (size
, 0U))
2725 if (STACK_GROWS_DOWNWARD
)
2726 i
-= crtl
->args
.pretend_args_size
;
2728 i
+= crtl
->args
.pretend_args_size
;
2730 if (ARGS_GROW_DOWNWARD
)
2733 /* We can ignore any references to the function's pretend args,
2734 which at this point would manifest as negative values of I. */
2735 if (known_le (i
, 0) && known_le (size
, poly_uint64 (-i
)))
2738 start
= maybe_lt (i
, 0) ? 0 : constant_lower_bound (i
);
2739 if (!(i
+ size
).is_constant (&end
))
2740 end
= HOST_WIDE_INT_M1U
;
2742 if (end
> stored_args_watermark
)
2745 end
= MIN (end
, SBITMAP_SIZE (stored_args_map
));
2746 for (unsigned HOST_WIDE_INT k
= start
; k
< end
; ++k
)
2747 if (bitmap_bit_p (stored_args_map
, k
))
2753 /* Do the register loads required for any wholly-register parms or any
2754 parms which are passed both on the stack and in a register. Their
2755 expressions were already evaluated.
2757 Mark all register-parms as living through the call, putting these USE
2758 insns in the CALL_INSN_FUNCTION_USAGE field.
2760 When IS_SIBCALL, perform the check_sibcall_argument_overlap
2761 checking, setting *SIBCALL_FAILURE if appropriate. */
2764 load_register_parameters (struct arg_data
*args
, int num_actuals
,
2765 rtx
*call_fusage
, int flags
, int is_sibcall
,
2766 int *sibcall_failure
)
2770 for (i
= 0; i
< num_actuals
; i
++)
2772 rtx reg
= ((flags
& ECF_SIBCALL
)
2773 ? args
[i
].tail_call_reg
: args
[i
].reg
);
2776 int partial
= args
[i
].partial
;
2778 poly_int64 size
= 0;
2779 HOST_WIDE_INT const_size
= 0;
2780 rtx_insn
*before_arg
= get_last_insn ();
2781 tree type
= TREE_TYPE (args
[i
].tree_value
);
2782 if (RECORD_OR_UNION_TYPE_P (type
) && TYPE_TRANSPARENT_AGGR (type
))
2783 type
= TREE_TYPE (first_field (type
));
2784 /* Set non-negative if we must move a word at a time, even if
2785 just one word (e.g, partial == 4 && mode == DFmode). Set
2786 to -1 if we just use a normal move insn. This value can be
2787 zero if the argument is a zero size structure. */
2789 if (GET_CODE (reg
) == PARALLEL
)
2793 gcc_assert (partial
% UNITS_PER_WORD
== 0);
2794 nregs
= partial
/ UNITS_PER_WORD
;
2796 else if (TYPE_MODE (type
) == BLKmode
)
2798 /* Variable-sized parameters should be described by a
2799 PARALLEL instead. */
2800 const_size
= int_size_in_bytes (type
);
2801 gcc_assert (const_size
>= 0);
2802 nregs
= (const_size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
2806 size
= GET_MODE_SIZE (args
[i
].mode
);
2808 /* Handle calls that pass values in multiple non-contiguous
2809 locations. The Irix 6 ABI has examples of this. */
2811 if (GET_CODE (reg
) == PARALLEL
)
2812 emit_group_move (reg
, args
[i
].parallel_value
);
2814 /* If simple case, just do move. If normal partial, store_one_arg
2815 has already loaded the register for us. In all other cases,
2816 load the register(s) from memory. */
2818 else if (nregs
== -1)
2820 emit_move_insn (reg
, args
[i
].value
);
2821 #ifdef BLOCK_REG_PADDING
2822 /* Handle case where we have a value that needs shifting
2823 up to the msb. eg. a QImode value and we're padding
2824 upward on a BYTES_BIG_ENDIAN machine. */
2825 if (args
[i
].locate
.where_pad
2826 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
))
2828 gcc_checking_assert (ordered_p (size
, UNITS_PER_WORD
));
2829 if (maybe_lt (size
, UNITS_PER_WORD
))
2833 = (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2835 /* Assigning REG here rather than a temp makes
2836 CALL_FUSAGE report the whole reg as used.
2837 Strictly speaking, the call only uses SIZE
2838 bytes at the msb end, but it doesn't seem worth
2839 generating rtl to say that. */
2840 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
2841 x
= expand_shift (LSHIFT_EXPR
, word_mode
,
2842 reg
, shift
, reg
, 1);
2844 emit_move_insn (reg
, x
);
2850 /* If we have pre-computed the values to put in the registers in
2851 the case of non-aligned structures, copy them in now. */
2853 else if (args
[i
].n_aligned_regs
!= 0)
2854 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
2855 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
2856 args
[i
].aligned_regs
[j
]);
2858 else if (partial
== 0 || args
[i
].pass_on_stack
)
2860 /* SIZE and CONST_SIZE are 0 for partial arguments and
2861 the size of a BLKmode type otherwise. */
2862 gcc_checking_assert (known_eq (size
, const_size
));
2863 rtx mem
= validize_mem (copy_rtx (args
[i
].value
));
2865 /* Check for overlap with already clobbered argument area,
2866 providing that this has non-zero size. */
2869 && (mem_might_overlap_already_clobbered_arg_p
2870 (XEXP (args
[i
].value
, 0), const_size
)))
2871 *sibcall_failure
= 1;
2873 if (const_size
% UNITS_PER_WORD
== 0
2874 || MEM_ALIGN (mem
) % BITS_PER_WORD
== 0)
2875 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
2879 move_block_to_reg (REGNO (reg
), mem
, nregs
- 1,
2881 rtx dest
= gen_rtx_REG (word_mode
, REGNO (reg
) + nregs
- 1);
2882 unsigned int bitoff
= (nregs
- 1) * BITS_PER_WORD
;
2883 unsigned int bitsize
= const_size
* BITS_PER_UNIT
- bitoff
;
2884 rtx x
= extract_bit_field (mem
, bitsize
, bitoff
, 1, dest
,
2885 word_mode
, word_mode
, false,
2887 if (BYTES_BIG_ENDIAN
)
2888 x
= expand_shift (LSHIFT_EXPR
, word_mode
, x
,
2889 BITS_PER_WORD
- bitsize
, dest
, 1);
2891 emit_move_insn (dest
, x
);
2894 /* Handle a BLKmode that needs shifting. */
2895 if (nregs
== 1 && const_size
< UNITS_PER_WORD
2896 #ifdef BLOCK_REG_PADDING
2897 && args
[i
].locate
.where_pad
== PAD_DOWNWARD
2903 rtx dest
= gen_rtx_REG (word_mode
, REGNO (reg
));
2904 int shift
= (UNITS_PER_WORD
- const_size
) * BITS_PER_UNIT
;
2905 enum tree_code dir
= (BYTES_BIG_ENDIAN
2906 ? RSHIFT_EXPR
: LSHIFT_EXPR
);
2909 x
= expand_shift (dir
, word_mode
, dest
, shift
, dest
, 1);
2911 emit_move_insn (dest
, x
);
2915 /* When a parameter is a block, and perhaps in other cases, it is
2916 possible that it did a load from an argument slot that was
2917 already clobbered. */
2919 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
2920 *sibcall_failure
= 1;
2922 /* Handle calls that pass values in multiple non-contiguous
2923 locations. The Irix 6 ABI has examples of this. */
2924 if (GET_CODE (reg
) == PARALLEL
)
2925 use_group_regs (call_fusage
, reg
);
2926 else if (nregs
== -1)
2927 use_reg_mode (call_fusage
, reg
, TYPE_MODE (type
));
2929 use_regs (call_fusage
, REGNO (reg
), nregs
);
2934 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2935 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2936 bytes, then we would need to push some additional bytes to pad the
2937 arguments. So, we try to compute an adjust to the stack pointer for an
2938 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2939 bytes. Then, when the arguments are pushed the stack will be perfectly
2942 Return true if this optimization is possible, storing the adjustment
2943 in ADJUSTMENT_OUT and setting ARGS_SIZE->CONSTANT to the number of
2944 bytes that should be popped after the call. */
2947 combine_pending_stack_adjustment_and_call (poly_int64_pod
*adjustment_out
,
2948 poly_int64 unadjusted_args_size
,
2949 struct args_size
*args_size
,
2950 unsigned int preferred_unit_stack_boundary
)
2952 /* The number of bytes to pop so that the stack will be
2953 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2954 poly_int64 adjustment
;
2955 /* The alignment of the stack after the arguments are pushed, if we
2956 just pushed the arguments without adjust the stack here. */
2957 unsigned HOST_WIDE_INT unadjusted_alignment
;
2959 if (!known_misalignment (stack_pointer_delta
+ unadjusted_args_size
,
2960 preferred_unit_stack_boundary
,
2961 &unadjusted_alignment
))
2964 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2965 as possible -- leaving just enough left to cancel out the
2966 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2967 PENDING_STACK_ADJUST is non-negative, and congruent to
2968 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2970 /* Begin by trying to pop all the bytes. */
2971 unsigned HOST_WIDE_INT tmp_misalignment
;
2972 if (!known_misalignment (pending_stack_adjust
,
2973 preferred_unit_stack_boundary
,
2976 unadjusted_alignment
-= tmp_misalignment
;
2977 adjustment
= pending_stack_adjust
;
2978 /* Push enough additional bytes that the stack will be aligned
2979 after the arguments are pushed. */
2980 if (preferred_unit_stack_boundary
> 1 && unadjusted_alignment
)
2981 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
2983 /* We need to know whether the adjusted argument size
2984 (UNADJUSTED_ARGS_SIZE - ADJUSTMENT) constitutes an allocation
2985 or a deallocation. */
2986 if (!ordered_p (adjustment
, unadjusted_args_size
))
2989 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2990 bytes after the call. The right number is the entire
2991 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2992 by the arguments in the first place. */
2994 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
2996 *adjustment_out
= adjustment
;
3000 /* Scan X expression if it does not dereference any argument slots
3001 we already clobbered by tail call arguments (as noted in stored_args_map
3003 Return nonzero if X expression dereferences such argument slots,
3007 check_sibcall_argument_overlap_1 (rtx x
)
3016 code
= GET_CODE (x
);
3018 /* We need not check the operands of the CALL expression itself. */
3023 return (mem_might_overlap_already_clobbered_arg_p
3024 (XEXP (x
, 0), GET_MODE_SIZE (GET_MODE (x
))));
3026 /* Scan all subexpressions. */
3027 fmt
= GET_RTX_FORMAT (code
);
3028 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
3032 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
3035 else if (*fmt
== 'E')
3037 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
3038 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
3045 /* Scan sequence after INSN if it does not dereference any argument slots
3046 we already clobbered by tail call arguments (as noted in stored_args_map
3047 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
3048 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
3049 should be 0). Return nonzero if sequence after INSN dereferences such argument
3050 slots, zero otherwise. */
3053 check_sibcall_argument_overlap (rtx_insn
*insn
, struct arg_data
*arg
,
3054 int mark_stored_args_map
)
3056 poly_uint64 low
, high
;
3057 unsigned HOST_WIDE_INT const_low
, const_high
;
3059 if (insn
== NULL_RTX
)
3060 insn
= get_insns ();
3062 insn
= NEXT_INSN (insn
);
3064 for (; insn
; insn
= NEXT_INSN (insn
))
3066 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
3069 if (mark_stored_args_map
)
3071 if (ARGS_GROW_DOWNWARD
)
3072 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
3074 low
= arg
->locate
.slot_offset
.constant
;
3075 high
= low
+ arg
->locate
.size
.constant
;
3077 const_low
= constant_lower_bound (low
);
3078 if (high
.is_constant (&const_high
))
3079 for (unsigned HOST_WIDE_INT i
= const_low
; i
< const_high
; ++i
)
3080 bitmap_set_bit (stored_args_map
, i
);
3082 stored_args_watermark
= MIN (stored_args_watermark
, const_low
);
3084 return insn
!= NULL_RTX
;
3087 /* Given that a function returns a value of mode MODE at the most
3088 significant end of hard register VALUE, shift VALUE left or right
3089 as specified by LEFT_P. Return true if some action was needed. */
3092 shift_return_value (machine_mode mode
, bool left_p
, rtx value
)
3094 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
3095 machine_mode value_mode
= GET_MODE (value
);
3096 poly_int64 shift
= GET_MODE_BITSIZE (value_mode
) - GET_MODE_BITSIZE (mode
);
3098 if (known_eq (shift
, 0))
3101 /* Use ashr rather than lshr for right shifts. This is for the benefit
3102 of the MIPS port, which requires SImode values to be sign-extended
3103 when stored in 64-bit registers. */
3104 if (!force_expand_binop (value_mode
, left_p
? ashl_optab
: ashr_optab
,
3105 value
, gen_int_shift_amount (value_mode
, shift
),
3106 value
, 1, OPTAB_WIDEN
))
3111 /* If X is a likely-spilled register value, copy it to a pseudo
3112 register and return that register. Return X otherwise. */
3115 avoid_likely_spilled_reg (rtx x
)
3120 && HARD_REGISTER_P (x
)
3121 && targetm
.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x
))))
3123 /* Make sure that we generate a REG rather than a CONCAT.
3124 Moves into CONCATs can need nontrivial instructions,
3125 and the whole point of this function is to avoid
3126 using the hard register directly in such a situation. */
3127 generating_concat_p
= 0;
3128 new_rtx
= gen_reg_rtx (GET_MODE (x
));
3129 generating_concat_p
= 1;
3130 emit_move_insn (new_rtx
, x
);
3136 /* Helper function for expand_call.
3137 Return false is EXP is not implementable as a sibling call. */
3140 can_implement_as_sibling_call_p (tree exp
,
3141 rtx structure_value_addr
,
3143 int reg_parm_stack_space ATTRIBUTE_UNUSED
,
3147 const args_size
&args_size
)
3149 if (!targetm
.have_sibcall_epilogue ())
3151 maybe_complain_about_tail_call
3153 "machine description does not have"
3154 " a sibcall_epilogue instruction pattern");
3158 /* Doing sibling call optimization needs some work, since
3159 structure_value_addr can be allocated on the stack.
3160 It does not seem worth the effort since few optimizable
3161 sibling calls will return a structure. */
3162 if (structure_value_addr
!= NULL_RTX
)
3164 maybe_complain_about_tail_call (exp
, "callee returns a structure");
3168 #ifdef REG_PARM_STACK_SPACE
3169 /* If outgoing reg parm stack space changes, we cannot do sibcall. */
3170 if (OUTGOING_REG_PARM_STACK_SPACE (funtype
)
3171 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl
))
3172 || (reg_parm_stack_space
!= REG_PARM_STACK_SPACE (current_function_decl
)))
3174 maybe_complain_about_tail_call (exp
,
3175 "inconsistent size of stack space"
3176 " allocated for arguments which are"
3177 " passed in registers");
3182 /* Check whether the target is able to optimize the call
3184 if (!targetm
.function_ok_for_sibcall (fndecl
, exp
))
3186 maybe_complain_about_tail_call (exp
,
3187 "target is not able to optimize the"
3188 " call into a sibling call");
3192 /* Functions that do not return exactly once may not be sibcall
3194 if (flags
& ECF_RETURNS_TWICE
)
3196 maybe_complain_about_tail_call (exp
, "callee returns twice");
3199 if (flags
& ECF_NORETURN
)
3201 maybe_complain_about_tail_call (exp
, "callee does not return");
3205 if (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
))))
3207 maybe_complain_about_tail_call (exp
, "volatile function type");
3211 /* If the called function is nested in the current one, it might access
3212 some of the caller's arguments, but could clobber them beforehand if
3213 the argument areas are shared. */
3214 if (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
3216 maybe_complain_about_tail_call (exp
, "nested function");
3220 /* If this function requires more stack slots than the current
3221 function, we cannot change it into a sibling call.
3222 crtl->args.pretend_args_size is not part of the
3223 stack allocated by our caller. */
3224 if (maybe_gt (args_size
.constant
,
3225 crtl
->args
.size
- crtl
->args
.pretend_args_size
))
3227 maybe_complain_about_tail_call (exp
,
3228 "callee required more stack slots"
3229 " than the caller");
3233 /* If the callee pops its own arguments, then it must pop exactly
3234 the same number of arguments as the current function. */
3235 if (maybe_ne (targetm
.calls
.return_pops_args (fndecl
, funtype
,
3236 args_size
.constant
),
3237 targetm
.calls
.return_pops_args (current_function_decl
,
3239 (current_function_decl
),
3242 maybe_complain_about_tail_call (exp
,
3243 "inconsistent number of"
3244 " popped arguments");
3248 if (!lang_hooks
.decls
.ok_for_sibcall (fndecl
))
3250 maybe_complain_about_tail_call (exp
, "frontend does not support"
3255 /* All checks passed. */
3259 /* Update stack alignment when the parameter is passed in the stack
3260 since the outgoing parameter requires extra alignment on the calling
3264 update_stack_alignment_for_call (struct locate_and_pad_arg_data
*locate
)
3266 if (crtl
->stack_alignment_needed
< locate
->boundary
)
3267 crtl
->stack_alignment_needed
= locate
->boundary
;
3268 if (crtl
->preferred_stack_boundary
< locate
->boundary
)
3269 crtl
->preferred_stack_boundary
= locate
->boundary
;
3272 /* Generate all the code for a CALL_EXPR exp
3273 and return an rtx for its value.
3274 Store the value in TARGET (specified as an rtx) if convenient.
3275 If the value is stored in TARGET then TARGET is returned.
3276 If IGNORE is nonzero, then we ignore the value of the function call. */
3279 expand_call (tree exp
, rtx target
, int ignore
)
3281 /* Nonzero if we are currently expanding a call. */
3282 static int currently_expanding_call
= 0;
3284 /* RTX for the function to be called. */
3286 /* Sequence of insns to perform a normal "call". */
3287 rtx_insn
*normal_call_insns
= NULL
;
3288 /* Sequence of insns to perform a tail "call". */
3289 rtx_insn
*tail_call_insns
= NULL
;
3290 /* Data type of the function. */
3292 tree type_arg_types
;
3294 /* Declaration of the function being called,
3295 or 0 if the function is computed (not known by name). */
3297 /* The type of the function being called. */
3299 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
3300 bool must_tail_call
= CALL_EXPR_MUST_TAIL_CALL (exp
);
3303 /* Register in which non-BLKmode value will be returned,
3304 or 0 if no value or if value is BLKmode. */
3306 /* Address where we should return a BLKmode value;
3307 0 if value not BLKmode. */
3308 rtx structure_value_addr
= 0;
3309 /* Nonzero if that address is being passed by treating it as
3310 an extra, implicit first parameter. Otherwise,
3311 it is passed by being copied directly into struct_value_rtx. */
3312 int structure_value_addr_parm
= 0;
3313 /* Holds the value of implicit argument for the struct value. */
3314 tree structure_value_addr_value
= NULL_TREE
;
3315 /* Size of aggregate value wanted, or zero if none wanted
3316 or if we are using the non-reentrant PCC calling convention
3317 or expecting the value in registers. */
3318 poly_int64 struct_value_size
= 0;
3319 /* Nonzero if called function returns an aggregate in memory PCC style,
3320 by returning the address of where to find it. */
3321 int pcc_struct_value
= 0;
3322 rtx struct_value
= 0;
3324 /* Number of actual parameters in this call, including struct value addr. */
3326 /* Number of named args. Args after this are anonymous ones
3327 and they must all go on the stack. */
3329 /* Number of complex actual arguments that need to be split. */
3330 int num_complex_actuals
= 0;
3332 /* Vector of information about each argument.
3333 Arguments are numbered in the order they will be pushed,
3334 not the order they are written. */
3335 struct arg_data
*args
;
3337 /* Total size in bytes of all the stack-parms scanned so far. */
3338 struct args_size args_size
;
3339 struct args_size adjusted_args_size
;
3340 /* Size of arguments before any adjustments (such as rounding). */
3341 poly_int64 unadjusted_args_size
;
3342 /* Data on reg parms scanned so far. */
3343 CUMULATIVE_ARGS args_so_far_v
;
3344 cumulative_args_t args_so_far
;
3345 /* Nonzero if a reg parm has been scanned. */
3347 /* Nonzero if this is an indirect function call. */
3349 /* Nonzero if we must avoid push-insns in the args for this call.
3350 If stack space is allocated for register parameters, but not by the
3351 caller, then it is preallocated in the fixed part of the stack frame.
3352 So the entire argument block must then be preallocated (i.e., we
3353 ignore PUSH_ROUNDING in that case). */
3355 int must_preallocate
= !PUSH_ARGS
;
3357 /* Size of the stack reserved for parameter registers. */
3358 int reg_parm_stack_space
= 0;
3360 /* Address of space preallocated for stack parms
3361 (on machines that lack push insns), or 0 if space not preallocated. */
3364 /* Mask of ECF_ and ERF_ flags. */
3366 int return_flags
= 0;
3367 #ifdef REG_PARM_STACK_SPACE
3368 /* Define the boundary of the register parm stack space that needs to be
3370 int low_to_save
, high_to_save
;
3371 rtx save_area
= 0; /* Place that it is saved */
3374 unsigned int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3375 char *initial_stack_usage_map
= stack_usage_map
;
3376 unsigned HOST_WIDE_INT initial_stack_usage_watermark
= stack_usage_watermark
;
3377 char *stack_usage_map_buf
= NULL
;
3379 poly_int64 old_stack_allocated
;
3381 /* State variables to track stack modifications. */
3382 rtx old_stack_level
= 0;
3383 int old_stack_arg_under_construction
= 0;
3384 poly_int64 old_pending_adj
= 0;
3385 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3387 /* Some stack pointer alterations we make are performed via
3388 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
3389 which we then also need to save/restore along the way. */
3390 poly_int64 old_stack_pointer_delta
= 0;
3393 tree addr
= CALL_EXPR_FN (exp
);
3395 /* The alignment of the stack, in bits. */
3396 unsigned HOST_WIDE_INT preferred_stack_boundary
;
3397 /* The alignment of the stack, in bytes. */
3398 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
3399 /* The static chain value to use for this call. */
3400 rtx static_chain_value
;
3401 /* See if this is "nothrow" function call. */
3402 if (TREE_NOTHROW (exp
))
3403 flags
|= ECF_NOTHROW
;
3405 /* See if we can find a DECL-node for the actual function, and get the
3406 function attributes (flags) from the function decl or type node. */
3407 fndecl
= get_callee_fndecl (exp
);
3410 fntype
= TREE_TYPE (fndecl
);
3411 flags
|= flags_from_decl_or_type (fndecl
);
3412 return_flags
|= decl_return_flags (fndecl
);
3416 fntype
= TREE_TYPE (TREE_TYPE (addr
));
3417 flags
|= flags_from_decl_or_type (fntype
);
3418 if (CALL_EXPR_BY_DESCRIPTOR (exp
))
3419 flags
|= ECF_BY_DESCRIPTOR
;
3421 rettype
= TREE_TYPE (exp
);
3423 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
3425 /* Warn if this value is an aggregate type,
3426 regardless of which calling convention we are using for it. */
3427 if (AGGREGATE_TYPE_P (rettype
))
3428 warning (OPT_Waggregate_return
, "function call has aggregate value");
3430 /* If the result of a non looping pure or const function call is
3431 ignored (or void), and none of its arguments are volatile, we can
3432 avoid expanding the call and just evaluate the arguments for
3434 if ((flags
& (ECF_CONST
| ECF_PURE
))
3435 && (!(flags
& ECF_LOOPING_CONST_OR_PURE
))
3436 && (ignore
|| target
== const0_rtx
3437 || TYPE_MODE (rettype
) == VOIDmode
))
3439 bool volatilep
= false;
3441 call_expr_arg_iterator iter
;
3443 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3444 if (TREE_THIS_VOLATILE (arg
))
3452 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3453 expand_expr (arg
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
3458 #ifdef REG_PARM_STACK_SPACE
3459 reg_parm_stack_space
= REG_PARM_STACK_SPACE (!fndecl
? fntype
: fndecl
);
3462 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
3463 && reg_parm_stack_space
> 0 && PUSH_ARGS
)
3464 must_preallocate
= 1;
3466 /* Set up a place to return a structure. */
3468 /* Cater to broken compilers. */
3469 if (aggregate_value_p (exp
, fntype
))
3471 /* This call returns a big structure. */
3472 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
3474 #ifdef PCC_STATIC_STRUCT_RETURN
3476 pcc_struct_value
= 1;
3478 #else /* not PCC_STATIC_STRUCT_RETURN */
3480 if (!poly_int_tree_p (TYPE_SIZE_UNIT (rettype
), &struct_value_size
))
3481 struct_value_size
= -1;
3483 /* Even if it is semantically safe to use the target as the return
3484 slot, it may be not sufficiently aligned for the return type. */
3485 if (CALL_EXPR_RETURN_SLOT_OPT (exp
)
3488 /* If rettype is addressable, we may not create a temporary.
3489 If target is properly aligned at runtime and the compiler
3490 just doesn't know about it, it will work fine, otherwise it
3492 && (TREE_ADDRESSABLE (rettype
)
3493 || !(MEM_ALIGN (target
) < TYPE_ALIGN (rettype
)
3494 && targetm
.slow_unaligned_access (TYPE_MODE (rettype
),
3495 MEM_ALIGN (target
)))))
3496 structure_value_addr
= XEXP (target
, 0);
3499 /* For variable-sized objects, we must be called with a target
3500 specified. If we were to allocate space on the stack here,
3501 we would have no way of knowing when to free it. */
3502 rtx d
= assign_temp (rettype
, 1, 1);
3503 structure_value_addr
= XEXP (d
, 0);
3507 #endif /* not PCC_STATIC_STRUCT_RETURN */
3510 /* Figure out the amount to which the stack should be aligned. */
3511 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3514 struct cgraph_rtl_info
*i
= cgraph_node::rtl_info (fndecl
);
3515 /* Without automatic stack alignment, we can't increase preferred
3516 stack boundary. With automatic stack alignment, it is
3517 unnecessary since unless we can guarantee that all callers will
3518 align the outgoing stack properly, callee has to align its
3521 && i
->preferred_incoming_stack_boundary
3522 && i
->preferred_incoming_stack_boundary
< preferred_stack_boundary
)
3523 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
3526 /* Operand 0 is a pointer-to-function; get the type of the function. */
3527 funtype
= TREE_TYPE (addr
);
3528 gcc_assert (POINTER_TYPE_P (funtype
));
3529 funtype
= TREE_TYPE (funtype
);
3531 /* Count whether there are actual complex arguments that need to be split
3532 into their real and imaginary parts. Munge the type_arg_types
3533 appropriately here as well. */
3534 if (targetm
.calls
.split_complex_arg
)
3536 call_expr_arg_iterator iter
;
3538 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3540 tree type
= TREE_TYPE (arg
);
3541 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
3542 && targetm
.calls
.split_complex_arg (type
))
3543 num_complex_actuals
++;
3545 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
3548 type_arg_types
= TYPE_ARG_TYPES (funtype
);
3550 if (flags
& ECF_MAY_BE_ALLOCA
)
3551 cfun
->calls_alloca
= 1;
3553 /* If struct_value_rtx is 0, it means pass the address
3554 as if it were an extra parameter. Put the argument expression
3555 in structure_value_addr_value. */
3556 if (structure_value_addr
&& struct_value
== 0)
3558 /* If structure_value_addr is a REG other than
3559 virtual_outgoing_args_rtx, we can use always use it. If it
3560 is not a REG, we must always copy it into a register.
3561 If it is virtual_outgoing_args_rtx, we must copy it to another
3562 register in some cases. */
3563 rtx temp
= (!REG_P (structure_value_addr
)
3564 || (ACCUMULATE_OUTGOING_ARGS
3565 && stack_arg_under_construction
3566 && structure_value_addr
== virtual_outgoing_args_rtx
)
3567 ? copy_addr_to_reg (convert_memory_address
3568 (Pmode
, structure_value_addr
))
3569 : structure_value_addr
);
3571 structure_value_addr_value
=
3572 make_tree (build_pointer_type (TREE_TYPE (funtype
)), temp
);
3573 structure_value_addr_parm
= 1;
3576 /* Count the arguments and set NUM_ACTUALS. */
3578 call_expr_nargs (exp
) + num_complex_actuals
+ structure_value_addr_parm
;
3580 /* Compute number of named args.
3581 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
3583 if (type_arg_types
!= 0)
3585 = (list_length (type_arg_types
)
3586 /* Count the struct value address, if it is passed as a parm. */
3587 + structure_value_addr_parm
);
3589 /* If we know nothing, treat all args as named. */
3590 n_named_args
= num_actuals
;
3592 /* Start updating where the next arg would go.
3594 On some machines (such as the PA) indirect calls have a different
3595 calling convention than normal calls. The fourth argument in
3596 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
3598 INIT_CUMULATIVE_ARGS (args_so_far_v
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
3599 args_so_far
= pack_cumulative_args (&args_so_far_v
);
3601 /* Now possibly adjust the number of named args.
3602 Normally, don't include the last named arg if anonymous args follow.
3603 We do include the last named arg if
3604 targetm.calls.strict_argument_naming() returns nonzero.
3605 (If no anonymous args follow, the result of list_length is actually
3606 one too large. This is harmless.)
3608 If targetm.calls.pretend_outgoing_varargs_named() returns
3609 nonzero, and targetm.calls.strict_argument_naming() returns zero,
3610 this machine will be able to place unnamed args that were passed
3611 in registers into the stack. So treat all args as named. This
3612 allows the insns emitting for a specific argument list to be
3613 independent of the function declaration.
3615 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
3616 we do not have any reliable way to pass unnamed args in
3617 registers, so we must force them into memory. */
3619 if (type_arg_types
!= 0
3620 && targetm
.calls
.strict_argument_naming (args_so_far
))
3622 else if (type_arg_types
!= 0
3623 && ! targetm
.calls
.pretend_outgoing_varargs_named (args_so_far
))
3624 /* Don't include the last named arg. */
3627 /* Treat all args as named. */
3628 n_named_args
= num_actuals
;
3630 /* Make a vector to hold all the information about each arg. */
3631 args
= XCNEWVEC (struct arg_data
, num_actuals
);
3633 /* Build up entries in the ARGS array, compute the size of the
3634 arguments into ARGS_SIZE, etc. */
3635 initialize_argument_information (num_actuals
, args
, &args_size
,
3637 structure_value_addr_value
, fndecl
, fntype
,
3638 args_so_far
, reg_parm_stack_space
,
3639 &old_stack_level
, &old_pending_adj
,
3640 &must_preallocate
, &flags
,
3641 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
3644 must_preallocate
= 1;
3646 /* Now make final decision about preallocating stack space. */
3647 must_preallocate
= finalize_must_preallocate (must_preallocate
,
3651 /* If the structure value address will reference the stack pointer, we
3652 must stabilize it. We don't need to do this if we know that we are
3653 not going to adjust the stack pointer in processing this call. */
3655 if (structure_value_addr
3656 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
3657 || reg_mentioned_p (virtual_outgoing_args_rtx
,
3658 structure_value_addr
))
3660 || (!ACCUMULATE_OUTGOING_ARGS
3661 && maybe_ne (args_size
.constant
, 0))))
3662 structure_value_addr
= copy_to_reg (structure_value_addr
);
3664 /* Tail calls can make things harder to debug, and we've traditionally
3665 pushed these optimizations into -O2. Don't try if we're already
3666 expanding a call, as that means we're an argument. Don't try if
3667 there's cleanups, as we know there's code to follow the call. */
3668 if (currently_expanding_call
++ != 0
3669 || (!flag_optimize_sibling_calls
&& !CALL_FROM_THUNK_P (exp
))
3671 || dbg_cnt (tail_call
) == false)
3674 /* Workaround buggy C/C++ wrappers around Fortran routines with
3675 character(len=constant) arguments if the hidden string length arguments
3676 are passed on the stack; if the callers forget to pass those arguments,
3677 attempting to tail call in such routines leads to stack corruption.
3678 Avoid tail calls in functions where at least one such hidden string
3679 length argument is passed (partially or fully) on the stack in the
3680 caller and the callee needs to pass any arguments on the stack.
3682 if (try_tail_call
&& maybe_ne (args_size
.constant
, 0))
3683 for (tree arg
= DECL_ARGUMENTS (current_function_decl
);
3684 arg
; arg
= DECL_CHAIN (arg
))
3685 if (DECL_HIDDEN_STRING_LENGTH (arg
) && DECL_INCOMING_RTL (arg
))
3687 subrtx_iterator::array_type array
;
3688 FOR_EACH_SUBRTX (iter
, array
, DECL_INCOMING_RTL (arg
), NONCONST
)
3696 /* If the user has marked the function as requiring tail-call
3697 optimization, attempt it. */
3701 /* Rest of purposes for tail call optimizations to fail. */
3703 try_tail_call
= can_implement_as_sibling_call_p (exp
,
3704 structure_value_addr
,
3706 reg_parm_stack_space
,
3708 flags
, addr
, args_size
);
3710 /* Check if caller and callee disagree in promotion of function
3714 machine_mode caller_mode
, caller_promoted_mode
;
3715 machine_mode callee_mode
, callee_promoted_mode
;
3716 int caller_unsignedp
, callee_unsignedp
;
3717 tree caller_res
= DECL_RESULT (current_function_decl
);
3719 caller_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (caller_res
));
3720 caller_mode
= DECL_MODE (caller_res
);
3721 callee_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (funtype
));
3722 callee_mode
= TYPE_MODE (TREE_TYPE (funtype
));
3723 caller_promoted_mode
3724 = promote_function_mode (TREE_TYPE (caller_res
), caller_mode
,
3726 TREE_TYPE (current_function_decl
), 1);
3727 callee_promoted_mode
3728 = promote_function_mode (TREE_TYPE (funtype
), callee_mode
,
3731 if (caller_mode
!= VOIDmode
3732 && (caller_promoted_mode
!= callee_promoted_mode
3733 || ((caller_mode
!= caller_promoted_mode
3734 || callee_mode
!= callee_promoted_mode
)
3735 && (caller_unsignedp
!= callee_unsignedp
3736 || partial_subreg_p (caller_mode
, callee_mode
)))))
3739 maybe_complain_about_tail_call (exp
,
3740 "caller and callee disagree in"
3741 " promotion of function"
3746 /* Ensure current function's preferred stack boundary is at least
3747 what we need. Stack alignment may also increase preferred stack
3749 for (i
= 0; i
< num_actuals
; i
++)
3750 if (reg_parm_stack_space
> 0
3752 || args
[i
].partial
!= 0
3753 || args
[i
].pass_on_stack
)
3754 update_stack_alignment_for_call (&args
[i
].locate
);
3755 if (crtl
->preferred_stack_boundary
< preferred_stack_boundary
)
3756 crtl
->preferred_stack_boundary
= preferred_stack_boundary
;
3758 preferred_stack_boundary
= crtl
->preferred_stack_boundary
;
3760 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
3762 /* We want to make two insn chains; one for a sibling call, the other
3763 for a normal call. We will select one of the two chains after
3764 initial RTL generation is complete. */
3765 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
3767 int sibcall_failure
= 0;
3768 /* We want to emit any pending stack adjustments before the tail
3769 recursion "call". That way we know any adjustment after the tail
3770 recursion call can be ignored if we indeed use the tail
3772 saved_pending_stack_adjust save
;
3773 rtx_insn
*insns
, *before_call
, *after_args
;
3778 /* State variables we need to save and restore between
3780 save_pending_stack_adjust (&save
);
3783 flags
&= ~ECF_SIBCALL
;
3785 flags
|= ECF_SIBCALL
;
3787 /* Other state variables that we must reinitialize each time
3788 through the loop (that are not initialized by the loop itself). */
3792 /* Start a new sequence for the normal call case.
3794 From this point on, if the sibling call fails, we want to set
3795 sibcall_failure instead of continuing the loop. */
3798 /* Don't let pending stack adjusts add up to too much.
3799 Also, do all pending adjustments now if there is any chance
3800 this might be a call to alloca or if we are expanding a sibling
3802 Also do the adjustments before a throwing call, otherwise
3803 exception handling can fail; PR 19225. */
3804 if (maybe_ge (pending_stack_adjust
, 32)
3805 || (maybe_ne (pending_stack_adjust
, 0)
3806 && (flags
& ECF_MAY_BE_ALLOCA
))
3807 || (maybe_ne (pending_stack_adjust
, 0)
3808 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
3810 do_pending_stack_adjust ();
3812 /* Precompute any arguments as needed. */
3814 precompute_arguments (num_actuals
, args
);
3816 /* Now we are about to start emitting insns that can be deleted
3817 if a libcall is deleted. */
3818 if (pass
&& (flags
& ECF_MALLOC
))
3822 && crtl
->stack_protect_guard
3823 && targetm
.stack_protect_runtime_enabled_p ())
3824 stack_protect_epilogue ();
3826 adjusted_args_size
= args_size
;
3827 /* Compute the actual size of the argument block required. The variable
3828 and constant sizes must be combined, the size may have to be rounded,
3829 and there may be a minimum required size. When generating a sibcall
3830 pattern, do not round up, since we'll be re-using whatever space our
3832 unadjusted_args_size
3833 = compute_argument_block_size (reg_parm_stack_space
,
3834 &adjusted_args_size
,
3837 : preferred_stack_boundary
));
3839 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
3841 /* The argument block when performing a sibling call is the
3842 incoming argument block. */
3845 argblock
= crtl
->args
.internal_arg_pointer
;
3846 if (STACK_GROWS_DOWNWARD
)
3848 = plus_constant (Pmode
, argblock
, crtl
->args
.pretend_args_size
);
3851 = plus_constant (Pmode
, argblock
, -crtl
->args
.pretend_args_size
);
3853 HOST_WIDE_INT map_size
= constant_lower_bound (args_size
.constant
);
3854 stored_args_map
= sbitmap_alloc (map_size
);
3855 bitmap_clear (stored_args_map
);
3856 stored_args_watermark
= HOST_WIDE_INT_M1U
;
3859 /* If we have no actual push instructions, or shouldn't use them,
3860 make space for all args right now. */
3861 else if (adjusted_args_size
.var
!= 0)
3863 if (old_stack_level
== 0)
3865 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
3866 old_stack_pointer_delta
= stack_pointer_delta
;
3867 old_pending_adj
= pending_stack_adjust
;
3868 pending_stack_adjust
= 0;
3869 /* stack_arg_under_construction says whether a stack arg is
3870 being constructed at the old stack level. Pushing the stack
3871 gets a clean outgoing argument block. */
3872 old_stack_arg_under_construction
= stack_arg_under_construction
;
3873 stack_arg_under_construction
= 0;
3875 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
3876 if (flag_stack_usage_info
)
3877 current_function_has_unbounded_dynamic_stack_size
= 1;
3881 /* Note that we must go through the motions of allocating an argument
3882 block even if the size is zero because we may be storing args
3883 in the area reserved for register arguments, which may be part of
3886 poly_int64 needed
= adjusted_args_size
.constant
;
3888 /* Store the maximum argument space used. It will be pushed by
3889 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
3892 crtl
->outgoing_args_size
= upper_bound (crtl
->outgoing_args_size
,
3895 if (must_preallocate
)
3897 if (ACCUMULATE_OUTGOING_ARGS
)
3899 /* Since the stack pointer will never be pushed, it is
3900 possible for the evaluation of a parm to clobber
3901 something we have already written to the stack.
3902 Since most function calls on RISC machines do not use
3903 the stack, this is uncommon, but must work correctly.
3905 Therefore, we save any area of the stack that was already
3906 written and that we are using. Here we set up to do this
3907 by making a new stack usage map from the old one. The
3908 actual save will be done by store_one_arg.
3910 Another approach might be to try to reorder the argument
3911 evaluations to avoid this conflicting stack usage. */
3913 /* Since we will be writing into the entire argument area,
3914 the map must be allocated for its entire size, not just
3915 the part that is the responsibility of the caller. */
3916 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3917 needed
+= reg_parm_stack_space
;
3919 poly_int64 limit
= needed
;
3920 if (ARGS_GROW_DOWNWARD
)
3923 /* For polynomial sizes, this is the maximum possible
3924 size needed for arguments with a constant size
3926 HOST_WIDE_INT const_limit
= constant_lower_bound (limit
);
3927 highest_outgoing_arg_in_use
3928 = MAX (initial_highest_arg_in_use
, const_limit
);
3930 free (stack_usage_map_buf
);
3931 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
3932 stack_usage_map
= stack_usage_map_buf
;
3934 if (initial_highest_arg_in_use
)
3935 memcpy (stack_usage_map
, initial_stack_usage_map
,
3936 initial_highest_arg_in_use
);
3938 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3939 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3940 (highest_outgoing_arg_in_use
3941 - initial_highest_arg_in_use
));
3944 /* The address of the outgoing argument list must not be
3945 copied to a register here, because argblock would be left
3946 pointing to the wrong place after the call to
3947 allocate_dynamic_stack_space below. */
3949 argblock
= virtual_outgoing_args_rtx
;
3953 /* Try to reuse some or all of the pending_stack_adjust
3954 to get this space. */
3955 if (inhibit_defer_pop
== 0
3956 && (combine_pending_stack_adjustment_and_call
3958 unadjusted_args_size
,
3959 &adjusted_args_size
,
3960 preferred_unit_stack_boundary
)))
3962 /* combine_pending_stack_adjustment_and_call computes
3963 an adjustment before the arguments are allocated.
3964 Account for them and see whether or not the stack
3965 needs to go up or down. */
3966 needed
= unadjusted_args_size
- needed
;
3969 combine_pending_stack_adjustment_and_call. */
3970 gcc_checking_assert (ordered_p (needed
, 0));
3971 if (maybe_lt (needed
, 0))
3973 /* We're releasing stack space. */
3974 /* ??? We can avoid any adjustment at all if we're
3975 already aligned. FIXME. */
3976 pending_stack_adjust
= -needed
;
3977 do_pending_stack_adjust ();
3981 /* We need to allocate space. We'll do that in
3982 push_block below. */
3983 pending_stack_adjust
= 0;
3986 /* Special case this because overhead of `push_block' in
3987 this case is non-trivial. */
3988 if (known_eq (needed
, 0))
3989 argblock
= virtual_outgoing_args_rtx
;
3992 rtx needed_rtx
= gen_int_mode (needed
, Pmode
);
3993 argblock
= push_block (needed_rtx
, 0, 0);
3994 if (ARGS_GROW_DOWNWARD
)
3995 argblock
= plus_constant (Pmode
, argblock
, needed
);
3998 /* We only really need to call `copy_to_reg' in the case
3999 where push insns are going to be used to pass ARGBLOCK
4000 to a function call in ARGS. In that case, the stack
4001 pointer changes value from the allocation point to the
4002 call point, and hence the value of
4003 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
4004 as well always do it. */
4005 argblock
= copy_to_reg (argblock
);
4010 if (ACCUMULATE_OUTGOING_ARGS
)
4012 /* The save/restore code in store_one_arg handles all
4013 cases except one: a constructor call (including a C
4014 function returning a BLKmode struct) to initialize
4016 if (stack_arg_under_construction
)
4020 (adjusted_args_size
.constant
4021 + (OUTGOING_REG_PARM_STACK_SPACE (!fndecl
? fntype
4022 : TREE_TYPE (fndecl
))
4023 ? 0 : reg_parm_stack_space
), Pmode
));
4024 if (old_stack_level
== 0)
4026 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
4027 old_stack_pointer_delta
= stack_pointer_delta
;
4028 old_pending_adj
= pending_stack_adjust
;
4029 pending_stack_adjust
= 0;
4030 /* stack_arg_under_construction says whether a stack
4031 arg is being constructed at the old stack level.
4032 Pushing the stack gets a clean outgoing argument
4034 old_stack_arg_under_construction
4035 = stack_arg_under_construction
;
4036 stack_arg_under_construction
= 0;
4037 /* Make a new map for the new argument list. */
4038 free (stack_usage_map_buf
);
4039 stack_usage_map_buf
= XCNEWVEC (char, highest_outgoing_arg_in_use
);
4040 stack_usage_map
= stack_usage_map_buf
;
4041 highest_outgoing_arg_in_use
= 0;
4042 stack_usage_watermark
= HOST_WIDE_INT_M1U
;
4044 /* We can pass TRUE as the 4th argument because we just
4045 saved the stack pointer and will restore it right after
4047 allocate_dynamic_stack_space (push_size
, 0, BIGGEST_ALIGNMENT
,
4051 /* If argument evaluation might modify the stack pointer,
4052 copy the address of the argument list to a register. */
4053 for (i
= 0; i
< num_actuals
; i
++)
4054 if (args
[i
].pass_on_stack
)
4056 argblock
= copy_addr_to_reg (argblock
);
4061 compute_argument_addresses (args
, argblock
, num_actuals
);
4063 /* Stack is properly aligned, pops can't safely be deferred during
4064 the evaluation of the arguments. */
4067 /* Precompute all register parameters. It isn't safe to compute
4068 anything once we have started filling any specific hard regs.
4069 TLS symbols sometimes need a call to resolve. Precompute
4070 register parameters before any stack pointer manipulation
4071 to avoid unaligned stack in the called function. */
4072 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
4076 /* Perform stack alignment before the first push (the last arg). */
4078 && maybe_gt (adjusted_args_size
.constant
, reg_parm_stack_space
)
4079 && maybe_ne (adjusted_args_size
.constant
, unadjusted_args_size
))
4081 /* When the stack adjustment is pending, we get better code
4082 by combining the adjustments. */
4083 if (maybe_ne (pending_stack_adjust
, 0)
4084 && ! inhibit_defer_pop
4085 && (combine_pending_stack_adjustment_and_call
4086 (&pending_stack_adjust
,
4087 unadjusted_args_size
,
4088 &adjusted_args_size
,
4089 preferred_unit_stack_boundary
)))
4090 do_pending_stack_adjust ();
4091 else if (argblock
== 0)
4092 anti_adjust_stack (gen_int_mode (adjusted_args_size
.constant
4093 - unadjusted_args_size
,
4096 /* Now that the stack is properly aligned, pops can't safely
4097 be deferred during the evaluation of the arguments. */
4100 /* Record the maximum pushed stack space size. We need to delay
4101 doing it this far to take into account the optimization done
4102 by combine_pending_stack_adjustment_and_call. */
4103 if (flag_stack_usage_info
4104 && !ACCUMULATE_OUTGOING_ARGS
4106 && adjusted_args_size
.var
== 0)
4108 poly_int64 pushed
= (adjusted_args_size
.constant
4109 + pending_stack_adjust
);
4110 current_function_pushed_stack_size
4111 = upper_bound (current_function_pushed_stack_size
, pushed
);
4114 funexp
= rtx_for_function_call (fndecl
, addr
);
4116 if (CALL_EXPR_STATIC_CHAIN (exp
))
4117 static_chain_value
= expand_normal (CALL_EXPR_STATIC_CHAIN (exp
));
4119 static_chain_value
= 0;
4121 #ifdef REG_PARM_STACK_SPACE
4122 /* Save the fixed argument area if it's part of the caller's frame and
4123 is clobbered by argument setup for this call. */
4124 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
4125 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
4126 &low_to_save
, &high_to_save
);
4129 /* Now store (and compute if necessary) all non-register parms.
4130 These come before register parms, since they can require block-moves,
4131 which could clobber the registers used for register parms.
4132 Parms which have partial registers are not stored here,
4133 but we do preallocate space here if they want that. */
4135 for (i
= 0; i
< num_actuals
; i
++)
4137 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
4139 rtx_insn
*before_arg
= get_last_insn ();
4141 /* We don't allow passing huge (> 2^30 B) arguments
4142 by value. It would cause an overflow later on. */
4143 if (constant_lower_bound (adjusted_args_size
.constant
)
4144 >= (1 << (HOST_BITS_PER_INT
- 2)))
4146 sorry ("passing too large argument on stack");
4150 if (store_one_arg (&args
[i
], argblock
, flags
,
4151 adjusted_args_size
.var
!= 0,
4152 reg_parm_stack_space
)
4154 && check_sibcall_argument_overlap (before_arg
,
4156 sibcall_failure
= 1;
4161 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
4162 gen_rtx_USE (VOIDmode
, args
[i
].stack
),
4166 /* If we have a parm that is passed in registers but not in memory
4167 and whose alignment does not permit a direct copy into registers,
4168 make a group of pseudos that correspond to each register that we
4170 if (STRICT_ALIGNMENT
)
4171 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
4173 /* Now store any partially-in-registers parm.
4174 This is the last place a block-move can happen. */
4176 for (i
= 0; i
< num_actuals
; i
++)
4177 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
4179 rtx_insn
*before_arg
= get_last_insn ();
4181 /* On targets with weird calling conventions (e.g. PA) it's
4182 hard to ensure that all cases of argument overlap between
4183 stack and registers work. Play it safe and bail out. */
4184 if (ARGS_GROW_DOWNWARD
&& !STACK_GROWS_DOWNWARD
)
4186 sibcall_failure
= 1;
4190 if (store_one_arg (&args
[i
], argblock
, flags
,
4191 adjusted_args_size
.var
!= 0,
4192 reg_parm_stack_space
)
4194 && check_sibcall_argument_overlap (before_arg
,
4196 sibcall_failure
= 1;
4199 bool any_regs
= false;
4200 for (i
= 0; i
< num_actuals
; i
++)
4201 if (args
[i
].reg
!= NULL_RTX
)
4204 targetm
.calls
.call_args (args
[i
].reg
, funtype
);
4207 targetm
.calls
.call_args (pc_rtx
, funtype
);
4209 /* Figure out the register where the value, if any, will come back. */
4211 if (TYPE_MODE (rettype
) != VOIDmode
4212 && ! structure_value_addr
)
4214 if (pcc_struct_value
)
4215 valreg
= hard_function_value (build_pointer_type (rettype
),
4216 fndecl
, NULL
, (pass
== 0));
4218 valreg
= hard_function_value (rettype
, fndecl
, fntype
,
4221 /* If VALREG is a PARALLEL whose first member has a zero
4222 offset, use that. This is for targets such as m68k that
4223 return the same value in multiple places. */
4224 if (GET_CODE (valreg
) == PARALLEL
)
4226 rtx elem
= XVECEXP (valreg
, 0, 0);
4227 rtx where
= XEXP (elem
, 0);
4228 rtx offset
= XEXP (elem
, 1);
4229 if (offset
== const0_rtx
4230 && GET_MODE (where
) == GET_MODE (valreg
))
4235 /* If register arguments require space on the stack and stack space
4236 was not preallocated, allocate stack space here for arguments
4237 passed in registers. */
4238 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
4239 && !ACCUMULATE_OUTGOING_ARGS
4240 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
4241 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
4243 /* Pass the function the address in which to return a
4245 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
4247 structure_value_addr
4248 = convert_memory_address (Pmode
, structure_value_addr
);
4249 emit_move_insn (struct_value
,
4251 force_operand (structure_value_addr
,
4254 if (REG_P (struct_value
))
4255 use_reg (&call_fusage
, struct_value
);
4258 after_args
= get_last_insn ();
4259 funexp
= prepare_call_address (fndecl
? fndecl
: fntype
, funexp
,
4260 static_chain_value
, &call_fusage
,
4261 reg_parm_seen
, flags
);
4263 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
4264 pass
== 0, &sibcall_failure
);
4266 /* Save a pointer to the last insn before the call, so that we can
4267 later safely search backwards to find the CALL_INSN. */
4268 before_call
= get_last_insn ();
4270 /* Set up next argument register. For sibling calls on machines
4271 with register windows this should be the incoming register. */
4273 next_arg_reg
= targetm
.calls
.function_incoming_arg
4274 (args_so_far
, function_arg_info::end_marker ());
4276 next_arg_reg
= targetm
.calls
.function_arg
4277 (args_so_far
, function_arg_info::end_marker ());
4279 if (pass
== 1 && (return_flags
& ERF_RETURNS_ARG
))
4281 int arg_nr
= return_flags
& ERF_RETURN_ARG_MASK
;
4282 arg_nr
= num_actuals
- arg_nr
- 1;
4284 && arg_nr
< num_actuals
4288 && GET_MODE (args
[arg_nr
].reg
) == GET_MODE (valreg
))
4290 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args
[arg_nr
].tree_value
)),
4291 gen_rtx_SET (valreg
, args
[arg_nr
].reg
),
4294 /* All arguments and registers used for the call must be set up by
4297 /* Stack must be properly aligned now. */
4299 || multiple_p (stack_pointer_delta
,
4300 preferred_unit_stack_boundary
));
4302 /* Generate the actual call instruction. */
4303 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
4304 adjusted_args_size
.constant
, struct_value_size
,
4305 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
4306 flags
, args_so_far
);
4310 rtx_call_insn
*last
;
4311 rtx datum
= NULL_RTX
;
4312 if (fndecl
!= NULL_TREE
)
4314 datum
= XEXP (DECL_RTL (fndecl
), 0);
4315 gcc_assert (datum
!= NULL_RTX
4316 && GET_CODE (datum
) == SYMBOL_REF
);
4318 last
= last_call_insn ();
4319 add_reg_note (last
, REG_CALL_DECL
, datum
);
4322 /* If the call setup or the call itself overlaps with anything
4323 of the argument setup we probably clobbered our call address.
4324 In that case we can't do sibcalls. */
4326 && check_sibcall_argument_overlap (after_args
, 0, 0))
4327 sibcall_failure
= 1;
4329 /* If a non-BLKmode value is returned at the most significant end
4330 of a register, shift the register right by the appropriate amount
4331 and update VALREG accordingly. BLKmode values are handled by the
4332 group load/store machinery below. */
4333 if (!structure_value_addr
4334 && !pcc_struct_value
4335 && TYPE_MODE (rettype
) != VOIDmode
4336 && TYPE_MODE (rettype
) != BLKmode
4338 && targetm
.calls
.return_in_msb (rettype
))
4340 if (shift_return_value (TYPE_MODE (rettype
), false, valreg
))
4341 sibcall_failure
= 1;
4342 valreg
= gen_rtx_REG (TYPE_MODE (rettype
), REGNO (valreg
));
4345 if (pass
&& (flags
& ECF_MALLOC
))
4347 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
4348 rtx_insn
*last
, *insns
;
4350 /* The return value from a malloc-like function is a pointer. */
4351 if (TREE_CODE (rettype
) == POINTER_TYPE
)
4352 mark_reg_pointer (temp
, MALLOC_ABI_ALIGNMENT
);
4354 emit_move_insn (temp
, valreg
);
4356 /* The return value from a malloc-like function cannot alias
4358 last
= get_last_insn ();
4359 add_reg_note (last
, REG_NOALIAS
, temp
);
4361 /* Write out the sequence. */
4362 insns
= get_insns ();
4368 /* For calls to `setjmp', etc., inform
4369 function.c:setjmp_warnings that it should complain if
4370 nonvolatile values are live. For functions that cannot
4371 return, inform flow that control does not fall through. */
4373 if ((flags
& ECF_NORETURN
) || pass
== 0)
4375 /* The barrier must be emitted
4376 immediately after the CALL_INSN. Some ports emit more
4377 than just a CALL_INSN above, so we must search for it here. */
4379 rtx_insn
*last
= get_last_insn ();
4380 while (!CALL_P (last
))
4382 last
= PREV_INSN (last
);
4383 /* There was no CALL_INSN? */
4384 gcc_assert (last
!= before_call
);
4387 emit_barrier_after (last
);
4389 /* Stack adjustments after a noreturn call are dead code.
4390 However when NO_DEFER_POP is in effect, we must preserve
4391 stack_pointer_delta. */
4392 if (inhibit_defer_pop
== 0)
4394 stack_pointer_delta
= old_stack_allocated
;
4395 pending_stack_adjust
= 0;
4399 /* If value type not void, return an rtx for the value. */
4401 if (TYPE_MODE (rettype
) == VOIDmode
4403 target
= const0_rtx
;
4404 else if (structure_value_addr
)
4406 if (target
== 0 || !MEM_P (target
))
4409 = gen_rtx_MEM (TYPE_MODE (rettype
),
4410 memory_address (TYPE_MODE (rettype
),
4411 structure_value_addr
));
4412 set_mem_attributes (target
, rettype
, 1);
4415 else if (pcc_struct_value
)
4417 /* This is the special C++ case where we need to
4418 know what the true target was. We take care to
4419 never use this value more than once in one expression. */
4420 target
= gen_rtx_MEM (TYPE_MODE (rettype
),
4421 copy_to_reg (valreg
));
4422 set_mem_attributes (target
, rettype
, 1);
4424 /* Handle calls that return values in multiple non-contiguous locations.
4425 The Irix 6 ABI has examples of this. */
4426 else if (GET_CODE (valreg
) == PARALLEL
)
4429 target
= emit_group_move_into_temps (valreg
);
4430 else if (rtx_equal_p (target
, valreg
))
4432 else if (GET_CODE (target
) == PARALLEL
)
4433 /* Handle the result of a emit_group_move_into_temps
4434 call in the previous pass. */
4435 emit_group_move (target
, valreg
);
4437 emit_group_store (target
, valreg
, rettype
,
4438 int_size_in_bytes (rettype
));
4441 && GET_MODE (target
) == TYPE_MODE (rettype
)
4442 && GET_MODE (target
) == GET_MODE (valreg
))
4444 bool may_overlap
= false;
4446 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
4447 reg to a plain register. */
4448 if (!REG_P (target
) || HARD_REGISTER_P (target
))
4449 valreg
= avoid_likely_spilled_reg (valreg
);
4451 /* If TARGET is a MEM in the argument area, and we have
4452 saved part of the argument area, then we can't store
4453 directly into TARGET as it may get overwritten when we
4454 restore the argument save area below. Don't work too
4455 hard though and simply force TARGET to a register if it
4456 is a MEM; the optimizer is quite likely to sort it out. */
4457 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
4458 for (i
= 0; i
< num_actuals
; i
++)
4459 if (args
[i
].save_area
)
4466 target
= copy_to_reg (valreg
);
4469 /* TARGET and VALREG cannot be equal at this point
4470 because the latter would not have
4471 REG_FUNCTION_VALUE_P true, while the former would if
4472 it were referring to the same register.
4474 If they refer to the same register, this move will be
4475 a no-op, except when function inlining is being
4477 emit_move_insn (target
, valreg
);
4479 /* If we are setting a MEM, this code must be executed.
4480 Since it is emitted after the call insn, sibcall
4481 optimization cannot be performed in that case. */
4483 sibcall_failure
= 1;
4487 target
= copy_to_reg (avoid_likely_spilled_reg (valreg
));
4489 /* If we promoted this return value, make the proper SUBREG.
4490 TARGET might be const0_rtx here, so be careful. */
4492 && TYPE_MODE (rettype
) != BLKmode
4493 && GET_MODE (target
) != TYPE_MODE (rettype
))
4495 tree type
= rettype
;
4496 int unsignedp
= TYPE_UNSIGNED (type
);
4499 /* Ensure we promote as expected, and get the new unsignedness. */
4500 pmode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
4502 gcc_assert (GET_MODE (target
) == pmode
);
4504 poly_uint64 offset
= subreg_lowpart_offset (TYPE_MODE (type
),
4506 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
4507 SUBREG_PROMOTED_VAR_P (target
) = 1;
4508 SUBREG_PROMOTED_SET (target
, unsignedp
);
4511 /* If size of args is variable or this was a constructor call for a stack
4512 argument, restore saved stack-pointer value. */
4514 if (old_stack_level
)
4516 rtx_insn
*prev
= get_last_insn ();
4518 emit_stack_restore (SAVE_BLOCK
, old_stack_level
);
4519 stack_pointer_delta
= old_stack_pointer_delta
;
4521 fixup_args_size_notes (prev
, get_last_insn (), stack_pointer_delta
);
4523 pending_stack_adjust
= old_pending_adj
;
4524 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
4525 stack_arg_under_construction
= old_stack_arg_under_construction
;
4526 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4527 stack_usage_map
= initial_stack_usage_map
;
4528 stack_usage_watermark
= initial_stack_usage_watermark
;
4529 sibcall_failure
= 1;
4531 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
4533 #ifdef REG_PARM_STACK_SPACE
4535 restore_fixed_argument_area (save_area
, argblock
,
4536 high_to_save
, low_to_save
);
4539 /* If we saved any argument areas, restore them. */
4540 for (i
= 0; i
< num_actuals
; i
++)
4541 if (args
[i
].save_area
)
4543 machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
4545 = gen_rtx_MEM (save_mode
,
4546 memory_address (save_mode
,
4547 XEXP (args
[i
].stack_slot
, 0)));
4549 if (save_mode
!= BLKmode
)
4550 emit_move_insn (stack_area
, args
[i
].save_area
);
4552 emit_block_move (stack_area
, args
[i
].save_area
,
4554 (args
[i
].locate
.size
.constant
, Pmode
)),
4555 BLOCK_OP_CALL_PARM
);
4558 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4559 stack_usage_map
= initial_stack_usage_map
;
4560 stack_usage_watermark
= initial_stack_usage_watermark
;
4563 /* If this was alloca, record the new stack level. */
4564 if (flags
& ECF_MAY_BE_ALLOCA
)
4565 record_new_stack_level ();
4567 /* Free up storage we no longer need. */
4568 for (i
= 0; i
< num_actuals
; ++i
)
4569 free (args
[i
].aligned_regs
);
4571 targetm
.calls
.end_call_args ();
4573 insns
= get_insns ();
4578 tail_call_insns
= insns
;
4580 /* Restore the pending stack adjustment now that we have
4581 finished generating the sibling call sequence. */
4583 restore_pending_stack_adjust (&save
);
4585 /* Prepare arg structure for next iteration. */
4586 for (i
= 0; i
< num_actuals
; i
++)
4589 args
[i
].aligned_regs
= 0;
4593 sbitmap_free (stored_args_map
);
4594 internal_arg_pointer_exp_state
.scan_start
= NULL
;
4595 internal_arg_pointer_exp_state
.cache
.release ();
4599 normal_call_insns
= insns
;
4601 /* Verify that we've deallocated all the stack we used. */
4602 gcc_assert ((flags
& ECF_NORETURN
)
4603 || known_eq (old_stack_allocated
,
4605 - pending_stack_adjust
));
4608 /* If something prevents making this a sibling call,
4609 zero out the sequence. */
4610 if (sibcall_failure
)
4611 tail_call_insns
= NULL
;
4616 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
4617 arguments too, as argument area is now clobbered by the call. */
4618 if (tail_call_insns
)
4620 emit_insn (tail_call_insns
);
4621 crtl
->tail_call_emit
= true;
4625 emit_insn (normal_call_insns
);
4627 /* Ideally we'd emit a message for all of the ways that it could
4629 maybe_complain_about_tail_call (exp
, "tail call production failed");
4632 currently_expanding_call
--;
4634 free (stack_usage_map_buf
);
4639 /* A sibling call sequence invalidates any REG_EQUIV notes made for
4640 this function's incoming arguments.
4642 At the start of RTL generation we know the only REG_EQUIV notes
4643 in the rtl chain are those for incoming arguments, so we can look
4644 for REG_EQUIV notes between the start of the function and the
4645 NOTE_INSN_FUNCTION_BEG.
4647 This is (slight) overkill. We could keep track of the highest
4648 argument we clobber and be more selective in removing notes, but it
4649 does not seem to be worth the effort. */
4652 fixup_tail_calls (void)
4656 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4660 /* There are never REG_EQUIV notes for the incoming arguments
4661 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
4663 && NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
)
4666 note
= find_reg_note (insn
, REG_EQUIV
, 0);
4668 remove_note (insn
, note
);
4669 note
= find_reg_note (insn
, REG_EQUIV
, 0);
4674 /* Traverse a list of TYPES and expand all complex types into their
4677 split_complex_types (tree types
)
4681 /* Before allocating memory, check for the common case of no complex. */
4682 for (p
= types
; p
; p
= TREE_CHAIN (p
))
4684 tree type
= TREE_VALUE (p
);
4685 if (TREE_CODE (type
) == COMPLEX_TYPE
4686 && targetm
.calls
.split_complex_arg (type
))
4692 types
= copy_list (types
);
4694 for (p
= types
; p
; p
= TREE_CHAIN (p
))
4696 tree complex_type
= TREE_VALUE (p
);
4698 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
4699 && targetm
.calls
.split_complex_arg (complex_type
))
4703 /* Rewrite complex type with component type. */
4704 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
4705 next
= TREE_CHAIN (p
);
4707 /* Add another component type for the imaginary part. */
4708 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
4709 TREE_CHAIN (p
) = imag
;
4710 TREE_CHAIN (imag
) = next
;
4712 /* Skip the newly created node. */
4720 /* Output a library call to function ORGFUN (a SYMBOL_REF rtx)
4721 for a value of mode OUTMODE,
4722 with NARGS different arguments, passed as ARGS.
4723 Store the return value if RETVAL is nonzero: store it in VALUE if
4724 VALUE is nonnull, otherwise pick a convenient location. In either
4725 case return the location of the stored value.
4727 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4728 `const' calls, LCT_PURE for `pure' calls, or another LCT_ value for
4729 other types of library calls. */
4732 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
4733 enum libcall_type fn_type
,
4734 machine_mode outmode
, int nargs
, rtx_mode_t
*args
)
4736 /* Total size in bytes of all the stack-parms scanned so far. */
4737 struct args_size args_size
;
4738 /* Size of arguments before any adjustments (such as rounding). */
4739 struct args_size original_args_size
;
4742 /* Todo, choose the correct decl type of orgfun. Sadly this information
4743 isn't present here, so we default to native calling abi here. */
4744 tree fndecl ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
4745 tree fntype ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
4748 CUMULATIVE_ARGS args_so_far_v
;
4749 cumulative_args_t args_so_far
;
4756 struct locate_and_pad_arg_data locate
;
4760 int old_inhibit_defer_pop
= inhibit_defer_pop
;
4761 rtx call_fusage
= 0;
4764 int pcc_struct_value
= 0;
4765 poly_int64 struct_value_size
= 0;
4767 int reg_parm_stack_space
= 0;
4769 rtx_insn
*before_call
;
4770 bool have_push_fusage
;
4771 tree tfom
; /* type_for_mode (outmode, 0) */
4773 #ifdef REG_PARM_STACK_SPACE
4774 /* Define the boundary of the register parm stack space that needs to be
4776 int low_to_save
= 0, high_to_save
= 0;
4777 rtx save_area
= 0; /* Place that it is saved. */
4780 /* Size of the stack reserved for parameter registers. */
4781 unsigned int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
4782 char *initial_stack_usage_map
= stack_usage_map
;
4783 unsigned HOST_WIDE_INT initial_stack_usage_watermark
= stack_usage_watermark
;
4784 char *stack_usage_map_buf
= NULL
;
4786 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
4788 #ifdef REG_PARM_STACK_SPACE
4789 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
4792 /* By default, library functions cannot throw. */
4793 flags
= ECF_NOTHROW
;
4806 flags
|= ECF_NORETURN
;
4809 flags
&= ~ECF_NOTHROW
;
4811 case LCT_RETURNS_TWICE
:
4812 flags
= ECF_RETURNS_TWICE
;
4817 /* Ensure current function's preferred stack boundary is at least
4819 if (crtl
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
4820 crtl
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
4822 /* If this kind of value comes back in memory,
4823 decide where in memory it should come back. */
4824 if (outmode
!= VOIDmode
)
4826 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
4827 if (aggregate_value_p (tfom
, 0))
4829 #ifdef PCC_STATIC_STRUCT_RETURN
4831 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
4832 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
4833 pcc_struct_value
= 1;
4835 value
= gen_reg_rtx (outmode
);
4836 #else /* not PCC_STATIC_STRUCT_RETURN */
4837 struct_value_size
= GET_MODE_SIZE (outmode
);
4838 if (value
!= 0 && MEM_P (value
))
4841 mem_value
= assign_temp (tfom
, 1, 1);
4843 /* This call returns a big structure. */
4844 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
4848 tfom
= void_type_node
;
4850 /* ??? Unfinished: must pass the memory address as an argument. */
4852 /* Copy all the libcall-arguments out of the varargs data
4853 and into a vector ARGVEC.
4855 Compute how to pass each argument. We only support a very small subset
4856 of the full argument passing conventions to limit complexity here since
4857 library functions shouldn't have many args. */
4859 argvec
= XALLOCAVEC (struct arg
, nargs
+ 1);
4860 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
4862 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
4863 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v
, outmode
, fun
);
4865 INIT_CUMULATIVE_ARGS (args_so_far_v
, NULL_TREE
, fun
, 0, nargs
);
4867 args_so_far
= pack_cumulative_args (&args_so_far_v
);
4869 args_size
.constant
= 0;
4876 /* If there's a structure value address to be passed,
4877 either pass it in the special place, or pass it as an extra argument. */
4878 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
4880 rtx addr
= XEXP (mem_value
, 0);
4884 /* Make sure it is a reasonable operand for a move or push insn. */
4885 if (!REG_P (addr
) && !MEM_P (addr
)
4886 && !(CONSTANT_P (addr
)
4887 && targetm
.legitimate_constant_p (Pmode
, addr
)))
4888 addr
= force_operand (addr
, NULL_RTX
);
4890 argvec
[count
].value
= addr
;
4891 argvec
[count
].mode
= Pmode
;
4892 argvec
[count
].partial
= 0;
4894 function_arg_info
ptr_arg (Pmode
, /*named=*/true);
4895 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
, ptr_arg
);
4896 gcc_assert (targetm
.calls
.arg_partial_bytes (args_so_far
, ptr_arg
) == 0);
4898 locate_and_pad_parm (Pmode
, NULL_TREE
,
4899 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4902 argvec
[count
].reg
!= 0,
4904 reg_parm_stack_space
, 0,
4905 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
4907 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
4908 || reg_parm_stack_space
> 0)
4909 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
4911 targetm
.calls
.function_arg_advance (args_so_far
, ptr_arg
);
4916 for (unsigned int i
= 0; count
< nargs
; i
++, count
++)
4918 rtx val
= args
[i
].first
;
4919 function_arg_info
arg (args
[i
].second
, /*named=*/true);
4922 /* We cannot convert the arg value to the mode the library wants here;
4923 must do it earlier where we know the signedness of the arg. */
4924 gcc_assert (arg
.mode
!= BLKmode
4925 && (GET_MODE (val
) == arg
.mode
4926 || GET_MODE (val
) == VOIDmode
));
4928 /* Make sure it is a reasonable operand for a move or push insn. */
4929 if (!REG_P (val
) && !MEM_P (val
)
4930 && !(CONSTANT_P (val
)
4931 && targetm
.legitimate_constant_p (arg
.mode
, val
)))
4932 val
= force_operand (val
, NULL_RTX
);
4934 if (pass_by_reference (&args_so_far_v
, arg
))
4937 int must_copy
= !reference_callee_copied (&args_so_far_v
, arg
);
4939 /* If this was a CONST function, it is now PURE since it now
4941 if (flags
& ECF_CONST
)
4943 flags
&= ~ECF_CONST
;
4947 if (MEM_P (val
) && !must_copy
)
4949 tree val_expr
= MEM_EXPR (val
);
4951 mark_addressable (val_expr
);
4956 slot
= assign_temp (lang_hooks
.types
.type_for_mode (arg
.mode
, 0),
4958 emit_move_insn (slot
, val
);
4961 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
4962 gen_rtx_USE (VOIDmode
, slot
),
4965 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
4966 gen_rtx_CLOBBER (VOIDmode
,
4971 arg
.pass_by_reference
= true;
4972 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
4975 arg
.mode
= promote_function_mode (NULL_TREE
, arg
.mode
, &unsigned_p
,
4977 argvec
[count
].mode
= arg
.mode
;
4978 argvec
[count
].value
= convert_modes (arg
.mode
, GET_MODE (val
), val
,
4980 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
, arg
);
4982 argvec
[count
].partial
4983 = targetm
.calls
.arg_partial_bytes (args_so_far
, arg
);
4985 if (argvec
[count
].reg
== 0
4986 || argvec
[count
].partial
!= 0
4987 || reg_parm_stack_space
> 0)
4989 locate_and_pad_parm (arg
.mode
, NULL_TREE
,
4990 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4993 argvec
[count
].reg
!= 0,
4995 reg_parm_stack_space
, argvec
[count
].partial
,
4996 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
4997 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
4998 gcc_assert (!argvec
[count
].locate
.size
.var
);
5000 #ifdef BLOCK_REG_PADDING
5002 /* The argument is passed entirely in registers. See at which
5003 end it should be padded. */
5004 argvec
[count
].locate
.where_pad
=
5005 BLOCK_REG_PADDING (arg
.mode
, NULL_TREE
,
5006 known_le (GET_MODE_SIZE (arg
.mode
),
5010 targetm
.calls
.function_arg_advance (args_so_far
, arg
);
5013 for (int i
= 0; i
< nargs
; i
++)
5014 if (reg_parm_stack_space
> 0
5015 || argvec
[i
].reg
== 0
5016 || argvec
[i
].partial
!= 0)
5017 update_stack_alignment_for_call (&argvec
[i
].locate
);
5019 /* If this machine requires an external definition for library
5020 functions, write one out. */
5021 assemble_external_libcall (fun
);
5023 original_args_size
= args_size
;
5024 args_size
.constant
= (aligned_upper_bound (args_size
.constant
5025 + stack_pointer_delta
,
5027 - stack_pointer_delta
);
5029 args_size
.constant
= upper_bound (args_size
.constant
,
5030 reg_parm_stack_space
);
5032 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
5033 args_size
.constant
-= reg_parm_stack_space
;
5035 crtl
->outgoing_args_size
= upper_bound (crtl
->outgoing_args_size
,
5036 args_size
.constant
);
5038 if (flag_stack_usage_info
&& !ACCUMULATE_OUTGOING_ARGS
)
5040 poly_int64 pushed
= args_size
.constant
+ pending_stack_adjust
;
5041 current_function_pushed_stack_size
5042 = upper_bound (current_function_pushed_stack_size
, pushed
);
5045 if (ACCUMULATE_OUTGOING_ARGS
)
5047 /* Since the stack pointer will never be pushed, it is possible for
5048 the evaluation of a parm to clobber something we have already
5049 written to the stack. Since most function calls on RISC machines
5050 do not use the stack, this is uncommon, but must work correctly.
5052 Therefore, we save any area of the stack that was already written
5053 and that we are using. Here we set up to do this by making a new
5054 stack usage map from the old one.
5056 Another approach might be to try to reorder the argument
5057 evaluations to avoid this conflicting stack usage. */
5059 needed
= args_size
.constant
;
5061 /* Since we will be writing into the entire argument area, the
5062 map must be allocated for its entire size, not just the part that
5063 is the responsibility of the caller. */
5064 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
5065 needed
+= reg_parm_stack_space
;
5067 poly_int64 limit
= needed
;
5068 if (ARGS_GROW_DOWNWARD
)
5071 /* For polynomial sizes, this is the maximum possible size needed
5072 for arguments with a constant size and offset. */
5073 HOST_WIDE_INT const_limit
= constant_lower_bound (limit
);
5074 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
5077 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
5078 stack_usage_map
= stack_usage_map_buf
;
5080 if (initial_highest_arg_in_use
)
5081 memcpy (stack_usage_map
, initial_stack_usage_map
,
5082 initial_highest_arg_in_use
);
5084 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
5085 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
5086 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
5089 /* We must be careful to use virtual regs before they're instantiated,
5090 and real regs afterwards. Loop optimization, for example, can create
5091 new libcalls after we've instantiated the virtual regs, and if we
5092 use virtuals anyway, they won't match the rtl patterns. */
5094 if (virtuals_instantiated
)
5095 argblock
= plus_constant (Pmode
, stack_pointer_rtx
,
5096 STACK_POINTER_OFFSET
);
5098 argblock
= virtual_outgoing_args_rtx
;
5103 argblock
= push_block (gen_int_mode (args_size
.constant
, Pmode
), 0, 0);
5106 /* We push args individually in reverse order, perform stack alignment
5107 before the first push (the last arg). */
5109 anti_adjust_stack (gen_int_mode (args_size
.constant
5110 - original_args_size
.constant
,
5115 #ifdef REG_PARM_STACK_SPACE
5116 if (ACCUMULATE_OUTGOING_ARGS
)
5118 /* The argument list is the property of the called routine and it
5119 may clobber it. If the fixed area has been used for previous
5120 parameters, we must save and restore it. */
5121 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
5122 &low_to_save
, &high_to_save
);
5126 /* When expanding a normal call, args are stored in push order,
5127 which is the reverse of what we have here. */
5128 bool any_regs
= false;
5129 for (int i
= nargs
; i
-- > 0; )
5130 if (argvec
[i
].reg
!= NULL_RTX
)
5132 targetm
.calls
.call_args (argvec
[i
].reg
, NULL_TREE
);
5136 targetm
.calls
.call_args (pc_rtx
, NULL_TREE
);
5138 /* Push the args that need to be pushed. */
5140 have_push_fusage
= false;
5142 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5143 are to be pushed. */
5144 for (count
= 0; count
< nargs
; count
++, argnum
--)
5146 machine_mode mode
= argvec
[argnum
].mode
;
5147 rtx val
= argvec
[argnum
].value
;
5148 rtx reg
= argvec
[argnum
].reg
;
5149 int partial
= argvec
[argnum
].partial
;
5150 unsigned int parm_align
= argvec
[argnum
].locate
.boundary
;
5151 poly_int64 lower_bound
= 0, upper_bound
= 0;
5153 if (! (reg
!= 0 && partial
== 0))
5157 if (ACCUMULATE_OUTGOING_ARGS
)
5159 /* If this is being stored into a pre-allocated, fixed-size,
5160 stack area, save any previous data at that location. */
5162 if (ARGS_GROW_DOWNWARD
)
5164 /* stack_slot is negative, but we want to index stack_usage_map
5165 with positive values. */
5166 upper_bound
= -argvec
[argnum
].locate
.slot_offset
.constant
+ 1;
5167 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
5171 lower_bound
= argvec
[argnum
].locate
.slot_offset
.constant
;
5172 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
5175 if (stack_region_maybe_used_p (lower_bound
, upper_bound
,
5176 reg_parm_stack_space
))
5178 /* We need to make a save area. */
5180 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
5181 machine_mode save_mode
5182 = int_mode_for_size (size
, 1).else_blk ();
5184 = plus_constant (Pmode
, argblock
,
5185 argvec
[argnum
].locate
.offset
.constant
);
5187 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
5189 if (save_mode
== BLKmode
)
5191 argvec
[argnum
].save_area
5192 = assign_stack_temp (BLKmode
,
5193 argvec
[argnum
].locate
.size
.constant
5196 emit_block_move (validize_mem
5197 (copy_rtx (argvec
[argnum
].save_area
)),
5200 (argvec
[argnum
].locate
.size
.constant
,
5202 BLOCK_OP_CALL_PARM
);
5206 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
5208 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
5213 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, parm_align
,
5214 partial
, reg
, 0, argblock
,
5216 (argvec
[argnum
].locate
.offset
.constant
, Pmode
)),
5217 reg_parm_stack_space
,
5218 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
), false);
5220 /* Now mark the segment we just used. */
5221 if (ACCUMULATE_OUTGOING_ARGS
)
5222 mark_stack_region_used (lower_bound
, upper_bound
);
5226 /* Indicate argument access so that alias.c knows that these
5229 use
= plus_constant (Pmode
, argblock
,
5230 argvec
[argnum
].locate
.offset
.constant
);
5231 else if (have_push_fusage
)
5235 /* When arguments are pushed, trying to tell alias.c where
5236 exactly this argument is won't work, because the
5237 auto-increment causes confusion. So we merely indicate
5238 that we access something with a known mode somewhere on
5240 use
= gen_rtx_PLUS (Pmode
, stack_pointer_rtx
,
5241 gen_rtx_SCRATCH (Pmode
));
5242 have_push_fusage
= true;
5244 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
5245 use
= gen_rtx_USE (VOIDmode
, use
);
5246 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
5252 fun
= prepare_call_address (NULL
, fun
, NULL
, &call_fusage
, 0, 0);
5254 /* Now load any reg parms into their regs. */
5256 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5257 are to be pushed. */
5258 for (count
= 0; count
< nargs
; count
++, argnum
--)
5260 machine_mode mode
= argvec
[argnum
].mode
;
5261 rtx val
= argvec
[argnum
].value
;
5262 rtx reg
= argvec
[argnum
].reg
;
5263 int partial
= argvec
[argnum
].partial
;
5265 /* Handle calls that pass values in multiple non-contiguous
5266 locations. The PA64 has examples of this for library calls. */
5267 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
5268 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
5269 else if (reg
!= 0 && partial
== 0)
5271 emit_move_insn (reg
, val
);
5272 #ifdef BLOCK_REG_PADDING
5273 poly_int64 size
= GET_MODE_SIZE (argvec
[argnum
].mode
);
5275 /* Copied from load_register_parameters. */
5277 /* Handle case where we have a value that needs shifting
5278 up to the msb. eg. a QImode value and we're padding
5279 upward on a BYTES_BIG_ENDIAN machine. */
5280 if (known_lt (size
, UNITS_PER_WORD
)
5281 && (argvec
[argnum
].locate
.where_pad
5282 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
5285 poly_int64 shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
5287 /* Assigning REG here rather than a temp makes CALL_FUSAGE
5288 report the whole reg as used. Strictly speaking, the
5289 call only uses SIZE bytes at the msb end, but it doesn't
5290 seem worth generating rtl to say that. */
5291 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
5292 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
, shift
, reg
, 1);
5294 emit_move_insn (reg
, x
);
5302 /* Any regs containing parms remain in use through the call. */
5303 for (count
= 0; count
< nargs
; count
++)
5305 rtx reg
= argvec
[count
].reg
;
5306 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
5307 use_group_regs (&call_fusage
, reg
);
5310 int partial
= argvec
[count
].partial
;
5314 gcc_assert (partial
% UNITS_PER_WORD
== 0);
5315 nregs
= partial
/ UNITS_PER_WORD
;
5316 use_regs (&call_fusage
, REGNO (reg
), nregs
);
5319 use_reg (&call_fusage
, reg
);
5323 /* Pass the function the address in which to return a structure value. */
5324 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
5326 emit_move_insn (struct_value
,
5328 force_operand (XEXP (mem_value
, 0),
5330 if (REG_P (struct_value
))
5331 use_reg (&call_fusage
, struct_value
);
5334 /* Don't allow popping to be deferred, since then
5335 cse'ing of library calls could delete a call and leave the pop. */
5337 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
5338 ? hard_libcall_value (outmode
, orgfun
) : NULL_RTX
);
5340 /* Stack must be properly aligned now. */
5341 gcc_assert (multiple_p (stack_pointer_delta
,
5342 PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
));
5344 before_call
= get_last_insn ();
5346 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
5347 will set inhibit_defer_pop to that value. */
5348 /* The return type is needed to decide how many bytes the function pops.
5349 Signedness plays no role in that, so for simplicity, we pretend it's
5350 always signed. We also assume that the list of arguments passed has
5351 no impact, so we pretend it is unknown. */
5353 emit_call_1 (fun
, NULL
,
5354 get_identifier (XSTR (orgfun
, 0)),
5355 build_function_type (tfom
, NULL_TREE
),
5356 original_args_size
.constant
, args_size
.constant
,
5358 targetm
.calls
.function_arg (args_so_far
,
5359 function_arg_info::end_marker ()),
5361 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, args_so_far
);
5366 gcc_assert (GET_CODE (datum
) == SYMBOL_REF
);
5367 rtx_call_insn
*last
= last_call_insn ();
5368 add_reg_note (last
, REG_CALL_DECL
, datum
);
5371 /* Right-shift returned value if necessary. */
5372 if (!pcc_struct_value
5373 && TYPE_MODE (tfom
) != BLKmode
5374 && targetm
.calls
.return_in_msb (tfom
))
5376 shift_return_value (TYPE_MODE (tfom
), false, valreg
);
5377 valreg
= gen_rtx_REG (TYPE_MODE (tfom
), REGNO (valreg
));
5380 targetm
.calls
.end_call_args ();
5382 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
5383 that it should complain if nonvolatile values are live. For
5384 functions that cannot return, inform flow that control does not
5386 if (flags
& ECF_NORETURN
)
5388 /* The barrier note must be emitted
5389 immediately after the CALL_INSN. Some ports emit more than
5390 just a CALL_INSN above, so we must search for it here. */
5391 rtx_insn
*last
= get_last_insn ();
5392 while (!CALL_P (last
))
5394 last
= PREV_INSN (last
);
5395 /* There was no CALL_INSN? */
5396 gcc_assert (last
!= before_call
);
5399 emit_barrier_after (last
);
5402 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
5403 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
5404 if (flags
& ECF_NOTHROW
)
5406 rtx_insn
*last
= get_last_insn ();
5407 while (!CALL_P (last
))
5409 last
= PREV_INSN (last
);
5410 /* There was no CALL_INSN? */
5411 gcc_assert (last
!= before_call
);
5414 make_reg_eh_region_note_nothrow_nononlocal (last
);
5417 /* Now restore inhibit_defer_pop to its actual original value. */
5422 /* Copy the value to the right place. */
5423 if (outmode
!= VOIDmode
&& retval
)
5429 if (value
!= mem_value
)
5430 emit_move_insn (value
, mem_value
);
5432 else if (GET_CODE (valreg
) == PARALLEL
)
5435 value
= gen_reg_rtx (outmode
);
5436 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
5440 /* Convert to the proper mode if a promotion has been active. */
5441 if (GET_MODE (valreg
) != outmode
)
5443 int unsignedp
= TYPE_UNSIGNED (tfom
);
5445 gcc_assert (promote_function_mode (tfom
, outmode
, &unsignedp
,
5446 fndecl
? TREE_TYPE (fndecl
) : fntype
, 1)
5447 == GET_MODE (valreg
));
5448 valreg
= convert_modes (outmode
, GET_MODE (valreg
), valreg
, 0);
5452 emit_move_insn (value
, valreg
);
5458 if (ACCUMULATE_OUTGOING_ARGS
)
5460 #ifdef REG_PARM_STACK_SPACE
5462 restore_fixed_argument_area (save_area
, argblock
,
5463 high_to_save
, low_to_save
);
5466 /* If we saved any argument areas, restore them. */
5467 for (count
= 0; count
< nargs
; count
++)
5468 if (argvec
[count
].save_area
)
5470 machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
5471 rtx adr
= plus_constant (Pmode
, argblock
,
5472 argvec
[count
].locate
.offset
.constant
);
5473 rtx stack_area
= gen_rtx_MEM (save_mode
,
5474 memory_address (save_mode
, adr
));
5476 if (save_mode
== BLKmode
)
5477 emit_block_move (stack_area
,
5479 (copy_rtx (argvec
[count
].save_area
)),
5481 (argvec
[count
].locate
.size
.constant
, Pmode
)),
5482 BLOCK_OP_CALL_PARM
);
5484 emit_move_insn (stack_area
, argvec
[count
].save_area
);
5487 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
5488 stack_usage_map
= initial_stack_usage_map
;
5489 stack_usage_watermark
= initial_stack_usage_watermark
;
5492 free (stack_usage_map_buf
);
5499 /* Store a single argument for a function call
5500 into the register or memory area where it must be passed.
5501 *ARG describes the argument value and where to pass it.
5503 ARGBLOCK is the address of the stack-block for all the arguments,
5504 or 0 on a machine where arguments are pushed individually.
5506 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
5507 so must be careful about how the stack is used.
5509 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
5510 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
5511 that we need not worry about saving and restoring the stack.
5513 FNDECL is the declaration of the function we are calling.
5515 Return nonzero if this arg should cause sibcall failure,
5519 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
5520 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
5522 tree pval
= arg
->tree_value
;
5525 poly_int64 used
= 0;
5526 poly_int64 lower_bound
= 0, upper_bound
= 0;
5527 int sibcall_failure
= 0;
5529 if (TREE_CODE (pval
) == ERROR_MARK
)
5532 /* Push a new temporary level for any temporaries we make for
5536 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
5538 /* If this is being stored into a pre-allocated, fixed-size, stack area,
5539 save any previous data at that location. */
5540 if (argblock
&& ! variable_size
&& arg
->stack
)
5542 if (ARGS_GROW_DOWNWARD
)
5544 /* stack_slot is negative, but we want to index stack_usage_map
5545 with positive values. */
5546 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
5548 rtx offset
= XEXP (XEXP (arg
->stack_slot
, 0), 1);
5549 upper_bound
= -rtx_to_poly_int64 (offset
) + 1;
5554 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
5558 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
5560 rtx offset
= XEXP (XEXP (arg
->stack_slot
, 0), 1);
5561 lower_bound
= rtx_to_poly_int64 (offset
);
5566 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
5569 if (stack_region_maybe_used_p (lower_bound
, upper_bound
,
5570 reg_parm_stack_space
))
5572 /* We need to make a save area. */
5573 poly_uint64 size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
5574 machine_mode save_mode
5575 = int_mode_for_size (size
, 1).else_blk ();
5576 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
5577 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
5579 if (save_mode
== BLKmode
)
5582 = assign_temp (TREE_TYPE (arg
->tree_value
), 1, 1);
5583 preserve_temp_slots (arg
->save_area
);
5584 emit_block_move (validize_mem (copy_rtx (arg
->save_area
)),
5587 (arg
->locate
.size
.constant
, Pmode
)),
5588 BLOCK_OP_CALL_PARM
);
5592 arg
->save_area
= gen_reg_rtx (save_mode
);
5593 emit_move_insn (arg
->save_area
, stack_area
);
5599 /* If this isn't going to be placed on both the stack and in registers,
5600 set up the register and number of words. */
5601 if (! arg
->pass_on_stack
)
5603 if (flags
& ECF_SIBCALL
)
5604 reg
= arg
->tail_call_reg
;
5607 partial
= arg
->partial
;
5610 /* Being passed entirely in a register. We shouldn't be called in
5612 gcc_assert (reg
== 0 || partial
!= 0);
5614 /* If this arg needs special alignment, don't load the registers
5616 if (arg
->n_aligned_regs
!= 0)
5619 /* If this is being passed partially in a register, we can't evaluate
5620 it directly into its stack slot. Otherwise, we can. */
5621 if (arg
->value
== 0)
5623 /* stack_arg_under_construction is nonzero if a function argument is
5624 being evaluated directly into the outgoing argument list and
5625 expand_call must take special action to preserve the argument list
5626 if it is called recursively.
5628 For scalar function arguments stack_usage_map is sufficient to
5629 determine which stack slots must be saved and restored. Scalar
5630 arguments in general have pass_on_stack == 0.
5632 If this argument is initialized by a function which takes the
5633 address of the argument (a C++ constructor or a C function
5634 returning a BLKmode structure), then stack_usage_map is
5635 insufficient and expand_call must push the stack around the
5636 function call. Such arguments have pass_on_stack == 1.
5638 Note that it is always safe to set stack_arg_under_construction,
5639 but this generates suboptimal code if set when not needed. */
5641 if (arg
->pass_on_stack
)
5642 stack_arg_under_construction
++;
5644 arg
->value
= expand_expr (pval
,
5646 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
5647 ? NULL_RTX
: arg
->stack
,
5648 VOIDmode
, EXPAND_STACK_PARM
);
5650 /* If we are promoting object (or for any other reason) the mode
5651 doesn't agree, convert the mode. */
5653 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
5654 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
5655 arg
->value
, arg
->unsignedp
);
5657 if (arg
->pass_on_stack
)
5658 stack_arg_under_construction
--;
5661 /* Check for overlap with already clobbered argument area. */
5662 if ((flags
& ECF_SIBCALL
)
5663 && MEM_P (arg
->value
)
5664 && mem_might_overlap_already_clobbered_arg_p (XEXP (arg
->value
, 0),
5665 arg
->locate
.size
.constant
))
5666 sibcall_failure
= 1;
5668 /* Don't allow anything left on stack from computation
5669 of argument to alloca. */
5670 if (flags
& ECF_MAY_BE_ALLOCA
)
5671 do_pending_stack_adjust ();
5673 if (arg
->value
== arg
->stack
)
5674 /* If the value is already in the stack slot, we are done. */
5676 else if (arg
->mode
!= BLKmode
)
5678 unsigned int parm_align
;
5680 /* Argument is a scalar, not entirely passed in registers.
5681 (If part is passed in registers, arg->partial says how much
5682 and emit_push_insn will take care of putting it there.)
5684 Push it, and if its size is less than the
5685 amount of space allocated to it,
5686 also bump stack pointer by the additional space.
5687 Note that in C the default argument promotions
5688 will prevent such mismatches. */
5690 poly_int64 size
= (TYPE_EMPTY_P (TREE_TYPE (pval
))
5691 ? 0 : GET_MODE_SIZE (arg
->mode
));
5693 /* Compute how much space the push instruction will push.
5694 On many machines, pushing a byte will advance the stack
5695 pointer by a halfword. */
5696 #ifdef PUSH_ROUNDING
5697 size
= PUSH_ROUNDING (size
);
5701 /* Compute how much space the argument should get:
5702 round up to a multiple of the alignment for arguments. */
5703 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5705 /* At the moment we don't (need to) support ABIs for which the
5706 padding isn't known at compile time. In principle it should
5707 be easy to add though. */
5708 used
= force_align_up (size
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
5710 /* Compute the alignment of the pushed argument. */
5711 parm_align
= arg
->locate
.boundary
;
5712 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5715 poly_int64 pad
= used
- size
;
5716 unsigned int pad_align
= known_alignment (pad
) * BITS_PER_UNIT
;
5718 parm_align
= MIN (parm_align
, pad_align
);
5721 /* This isn't already where we want it on the stack, so put it there.
5722 This can either be done with push or copy insns. */
5723 if (maybe_ne (used
, 0)
5724 && !emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
),
5725 NULL_RTX
, parm_align
, partial
, reg
, used
- size
,
5726 argblock
, ARGS_SIZE_RTX (arg
->locate
.offset
),
5727 reg_parm_stack_space
,
5728 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
), true))
5729 sibcall_failure
= 1;
5731 /* Unless this is a partially-in-register argument, the argument is now
5734 arg
->value
= arg
->stack
;
5738 /* BLKmode, at least partly to be pushed. */
5740 unsigned int parm_align
;
5744 /* Pushing a nonscalar.
5745 If part is passed in registers, PARTIAL says how much
5746 and emit_push_insn will take care of putting it there. */
5748 /* Round its size up to a multiple
5749 of the allocation unit for arguments. */
5751 if (arg
->locate
.size
.var
!= 0)
5754 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
5758 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
5759 for BLKmode is careful to avoid it. */
5760 excess
= (arg
->locate
.size
.constant
5761 - arg_int_size_in_bytes (TREE_TYPE (pval
))
5763 size_rtx
= expand_expr (arg_size_in_bytes (TREE_TYPE (pval
)),
5764 NULL_RTX
, TYPE_MODE (sizetype
),
5768 parm_align
= arg
->locate
.boundary
;
5770 /* When an argument is padded down, the block is aligned to
5771 PARM_BOUNDARY, but the actual argument isn't. */
5772 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5775 if (arg
->locate
.size
.var
)
5776 parm_align
= BITS_PER_UNIT
;
5779 unsigned int excess_align
5780 = known_alignment (excess
) * BITS_PER_UNIT
;
5781 if (excess_align
!= 0)
5782 parm_align
= MIN (parm_align
, excess_align
);
5786 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
5788 /* emit_push_insn might not work properly if arg->value and
5789 argblock + arg->locate.offset areas overlap. */
5793 if (strip_offset (XEXP (x
, 0), &i
)
5794 == crtl
->args
.internal_arg_pointer
)
5796 /* arg.locate doesn't contain the pretend_args_size offset,
5797 it's part of argblock. Ensure we don't count it in I. */
5798 if (STACK_GROWS_DOWNWARD
)
5799 i
-= crtl
->args
.pretend_args_size
;
5801 i
+= crtl
->args
.pretend_args_size
;
5803 /* expand_call should ensure this. */
5804 gcc_assert (!arg
->locate
.offset
.var
5805 && arg
->locate
.size
.var
== 0);
5806 poly_int64 size_val
= rtx_to_poly_int64 (size_rtx
);
5808 if (known_eq (arg
->locate
.offset
.constant
, i
))
5810 /* Even though they appear to be at the same location,
5811 if part of the outgoing argument is in registers,
5812 they aren't really at the same location. Check for
5813 this by making sure that the incoming size is the
5814 same as the outgoing size. */
5815 if (maybe_ne (arg
->locate
.size
.constant
, size_val
))
5816 sibcall_failure
= 1;
5818 else if (maybe_in_range_p (arg
->locate
.offset
.constant
,
5820 sibcall_failure
= 1;
5821 /* Use arg->locate.size.constant instead of size_rtx
5822 because we only care about the part of the argument
5824 else if (maybe_in_range_p (i
, arg
->locate
.offset
.constant
,
5825 arg
->locate
.size
.constant
))
5826 sibcall_failure
= 1;
5830 if (!CONST_INT_P (size_rtx
) || INTVAL (size_rtx
) != 0)
5831 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
5832 parm_align
, partial
, reg
, excess
, argblock
,
5833 ARGS_SIZE_RTX (arg
->locate
.offset
),
5834 reg_parm_stack_space
,
5835 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
), false);
5837 /* Unless this is a partially-in-register argument, the argument is now
5840 ??? Unlike the case above, in which we want the actual
5841 address of the data, so that we can load it directly into a
5842 register, here we want the address of the stack slot, so that
5843 it's properly aligned for word-by-word copying or something
5844 like that. It's not clear that this is always correct. */
5846 arg
->value
= arg
->stack_slot
;
5849 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
5851 tree type
= TREE_TYPE (arg
->tree_value
);
5853 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
5854 int_size_in_bytes (type
));
5857 /* Mark all slots this store used. */
5858 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
5859 && argblock
&& ! variable_size
&& arg
->stack
)
5860 mark_stack_region_used (lower_bound
, upper_bound
);
5862 /* Once we have pushed something, pops can't safely
5863 be deferred during the rest of the arguments. */
5866 /* Free any temporary slots made in processing this argument. */
5869 return sibcall_failure
;
5872 /* Nonzero if we do not know how to pass ARG solely in registers. */
5875 must_pass_in_stack_var_size (const function_arg_info
&arg
)
5880 /* If the type has variable size... */
5881 if (!poly_int_tree_p (TYPE_SIZE (arg
.type
)))
5884 /* If the type is marked as addressable (it is required
5885 to be constructed into the stack)... */
5886 if (TREE_ADDRESSABLE (arg
.type
))
5892 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5893 takes trailing padding of a structure into account. */
5894 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5897 must_pass_in_stack_var_size_or_pad (const function_arg_info
&arg
)
5902 /* If the type has variable size... */
5903 if (TREE_CODE (TYPE_SIZE (arg
.type
)) != INTEGER_CST
)
5906 /* If the type is marked as addressable (it is required
5907 to be constructed into the stack)... */
5908 if (TREE_ADDRESSABLE (arg
.type
))
5911 if (TYPE_EMPTY_P (arg
.type
))
5914 /* If the padding and mode of the type is such that a copy into
5915 a register would put it into the wrong part of the register. */
5916 if (arg
.mode
== BLKmode
5917 && int_size_in_bytes (arg
.type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
5918 && (targetm
.calls
.function_arg_padding (arg
.mode
, arg
.type
)
5919 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
5925 /* Return true if TYPE must be passed on the stack when passed to
5926 the "..." arguments of a function. */
5929 must_pass_va_arg_in_stack (tree type
)
5931 function_arg_info
arg (type
, /*named=*/false);
5932 return targetm
.calls
.must_pass_in_stack (arg
);
5935 /* Tell the garbage collector about GTY markers in this source file. */
5936 #include "gt-calls.h"