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, VOIDmode, void_type_node, true)
350 just after all the args have had their registers assigned.
351 This could be whatever you like, but normally it is the first
352 arg-register beyond those used for args in this call,
353 or 0 if all the arg-registers are used in this call.
354 It is passed on to `gen_call' so you can put this info in the call insn.
356 VALREG is a hard register in which a value is returned,
357 or 0 if the call does not return a value.
359 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
360 the args to this call were processed.
361 We restore `inhibit_defer_pop' to that value.
363 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
364 denote registers used by the called function. */
367 emit_call_1 (rtx funexp
, tree fntree ATTRIBUTE_UNUSED
, tree fndecl ATTRIBUTE_UNUSED
,
368 tree funtype ATTRIBUTE_UNUSED
,
369 poly_int64 stack_size ATTRIBUTE_UNUSED
,
370 poly_int64 rounded_stack_size
,
371 poly_int64 struct_value_size ATTRIBUTE_UNUSED
,
372 rtx next_arg_reg ATTRIBUTE_UNUSED
, rtx valreg
,
373 int old_inhibit_defer_pop
, rtx call_fusage
, int ecf_flags
,
374 cumulative_args_t args_so_far ATTRIBUTE_UNUSED
)
376 rtx rounded_stack_size_rtx
= gen_int_mode (rounded_stack_size
, Pmode
);
377 rtx call
, funmem
, pat
;
378 int already_popped
= 0;
379 poly_int64 n_popped
= 0;
381 /* Sibling call patterns never pop arguments (no sibcall(_value)_pop
382 patterns exist). Any popping that the callee does on return will
383 be from our caller's frame rather than ours. */
384 if (!(ecf_flags
& ECF_SIBCALL
))
386 n_popped
+= targetm
.calls
.return_pops_args (fndecl
, funtype
, stack_size
);
388 #ifdef CALL_POPS_ARGS
389 n_popped
+= CALL_POPS_ARGS (*get_cumulative_args (args_so_far
));
393 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
394 and we don't want to load it into a register as an optimization,
395 because prepare_call_address already did it if it should be done. */
396 if (GET_CODE (funexp
) != SYMBOL_REF
)
397 funexp
= memory_address (FUNCTION_MODE
, funexp
);
399 funmem
= gen_rtx_MEM (FUNCTION_MODE
, funexp
);
400 if (fndecl
&& TREE_CODE (fndecl
) == FUNCTION_DECL
)
404 /* Although a built-in FUNCTION_DECL and its non-__builtin
405 counterpart compare equal and get a shared mem_attrs, they
406 produce different dump output in compare-debug compilations,
407 if an entry gets garbage collected in one compilation, then
408 adds a different (but equivalent) entry, while the other
409 doesn't run the garbage collector at the same spot and then
410 shares the mem_attr with the equivalent entry. */
411 if (DECL_BUILT_IN_CLASS (t
) == BUILT_IN_NORMAL
)
413 tree t2
= builtin_decl_explicit (DECL_FUNCTION_CODE (t
));
418 set_mem_expr (funmem
, t
);
421 set_mem_expr (funmem
, build_simple_mem_ref (CALL_EXPR_FN (fntree
)));
423 if (ecf_flags
& ECF_SIBCALL
)
426 pat
= targetm
.gen_sibcall_value (valreg
, funmem
,
427 rounded_stack_size_rtx
,
428 next_arg_reg
, NULL_RTX
);
430 pat
= targetm
.gen_sibcall (funmem
, rounded_stack_size_rtx
,
432 gen_int_mode (struct_value_size
, Pmode
));
434 /* If the target has "call" or "call_value" insns, then prefer them
435 if no arguments are actually popped. If the target does not have
436 "call" or "call_value" insns, then we must use the popping versions
437 even if the call has no arguments to pop. */
438 else if (maybe_ne (n_popped
, 0)
440 ? targetm
.have_call_value ()
441 : targetm
.have_call ()))
443 rtx n_pop
= gen_int_mode (n_popped
, Pmode
);
445 /* If this subroutine pops its own args, record that in the call insn
446 if possible, for the sake of frame pointer elimination. */
449 pat
= targetm
.gen_call_value_pop (valreg
, funmem
,
450 rounded_stack_size_rtx
,
451 next_arg_reg
, n_pop
);
453 pat
= targetm
.gen_call_pop (funmem
, rounded_stack_size_rtx
,
454 next_arg_reg
, n_pop
);
461 pat
= targetm
.gen_call_value (valreg
, funmem
, rounded_stack_size_rtx
,
462 next_arg_reg
, NULL_RTX
);
464 pat
= targetm
.gen_call (funmem
, rounded_stack_size_rtx
, next_arg_reg
,
465 gen_int_mode (struct_value_size
, Pmode
));
469 /* Find the call we just emitted. */
470 rtx_call_insn
*call_insn
= last_call_insn ();
472 /* Some target create a fresh MEM instead of reusing the one provided
473 above. Set its MEM_EXPR. */
474 call
= get_call_rtx_from (call_insn
);
476 && MEM_EXPR (XEXP (call
, 0)) == NULL_TREE
477 && MEM_EXPR (funmem
) != NULL_TREE
)
478 set_mem_expr (XEXP (call
, 0), MEM_EXPR (funmem
));
480 /* Put the register usage information there. */
481 add_function_usage_to (call_insn
, call_fusage
);
483 /* If this is a const call, then set the insn's unchanging bit. */
484 if (ecf_flags
& ECF_CONST
)
485 RTL_CONST_CALL_P (call_insn
) = 1;
487 /* If this is a pure call, then set the insn's unchanging bit. */
488 if (ecf_flags
& ECF_PURE
)
489 RTL_PURE_CALL_P (call_insn
) = 1;
491 /* If this is a const call, then set the insn's unchanging bit. */
492 if (ecf_flags
& ECF_LOOPING_CONST_OR_PURE
)
493 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn
) = 1;
495 /* Create a nothrow REG_EH_REGION note, if needed. */
496 make_reg_eh_region_note (call_insn
, ecf_flags
, 0);
498 if (ecf_flags
& ECF_NORETURN
)
499 add_reg_note (call_insn
, REG_NORETURN
, const0_rtx
);
501 if (ecf_flags
& ECF_RETURNS_TWICE
)
503 add_reg_note (call_insn
, REG_SETJMP
, const0_rtx
);
504 cfun
->calls_setjmp
= 1;
507 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
509 /* Restore this now, so that we do defer pops for this call's args
510 if the context of the call as a whole permits. */
511 inhibit_defer_pop
= old_inhibit_defer_pop
;
513 if (maybe_ne (n_popped
, 0))
516 CALL_INSN_FUNCTION_USAGE (call_insn
)
517 = gen_rtx_EXPR_LIST (VOIDmode
,
518 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
519 CALL_INSN_FUNCTION_USAGE (call_insn
));
520 rounded_stack_size
-= n_popped
;
521 rounded_stack_size_rtx
= gen_int_mode (rounded_stack_size
, Pmode
);
522 stack_pointer_delta
-= n_popped
;
524 add_args_size_note (call_insn
, stack_pointer_delta
);
526 /* If popup is needed, stack realign must use DRAP */
527 if (SUPPORTS_STACK_ALIGNMENT
)
528 crtl
->need_drap
= true;
530 /* For noreturn calls when not accumulating outgoing args force
531 REG_ARGS_SIZE note to prevent crossjumping of calls with different
533 else if (!ACCUMULATE_OUTGOING_ARGS
&& (ecf_flags
& ECF_NORETURN
) != 0)
534 add_args_size_note (call_insn
, stack_pointer_delta
);
536 if (!ACCUMULATE_OUTGOING_ARGS
)
538 /* If returning from the subroutine does not automatically pop the args,
539 we need an instruction to pop them sooner or later.
540 Perhaps do it now; perhaps just record how much space to pop later.
542 If returning from the subroutine does pop the args, indicate that the
543 stack pointer will be changed. */
545 if (maybe_ne (rounded_stack_size
, 0))
547 if (ecf_flags
& ECF_NORETURN
)
548 /* Just pretend we did the pop. */
549 stack_pointer_delta
-= rounded_stack_size
;
550 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
551 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
552 pending_stack_adjust
+= rounded_stack_size
;
554 adjust_stack (rounded_stack_size_rtx
);
557 /* When we accumulate outgoing args, we must avoid any stack manipulations.
558 Restore the stack pointer to its original value now. Usually
559 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
560 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
561 popping variants of functions exist as well.
563 ??? We may optimize similar to defer_pop above, but it is
564 probably not worthwhile.
566 ??? It will be worthwhile to enable combine_stack_adjustments even for
568 else if (maybe_ne (n_popped
, 0))
569 anti_adjust_stack (gen_int_mode (n_popped
, Pmode
));
572 /* Determine if the function identified by FNDECL is one with
573 special properties we wish to know about. Modify FLAGS accordingly.
575 For example, if the function might return more than one time (setjmp), then
576 set ECF_RETURNS_TWICE.
578 Set ECF_MAY_BE_ALLOCA for any memory allocation function that might allocate
579 space from the stack such as alloca. */
582 special_function_p (const_tree fndecl
, int flags
)
584 tree name_decl
= DECL_NAME (fndecl
);
586 if (fndecl
&& name_decl
587 && IDENTIFIER_LENGTH (name_decl
) <= 11
588 /* Exclude functions not at the file scope, or not `extern',
589 since they are not the magic functions we would otherwise
591 FIXME: this should be handled with attributes, not with this
592 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
593 because you can declare fork() inside a function if you
595 && (DECL_CONTEXT (fndecl
) == NULL_TREE
596 || TREE_CODE (DECL_CONTEXT (fndecl
)) == TRANSLATION_UNIT_DECL
)
597 && TREE_PUBLIC (fndecl
))
599 const char *name
= IDENTIFIER_POINTER (name_decl
);
600 const char *tname
= name
;
602 /* We assume that alloca will always be called by name. It
603 makes no sense to pass it as a pointer-to-function to
604 anything that does not understand its behavior. */
605 if (IDENTIFIER_LENGTH (name_decl
) == 6
607 && ! strcmp (name
, "alloca"))
608 flags
|= ECF_MAY_BE_ALLOCA
;
610 /* Disregard prefix _ or __. */
619 /* ECF_RETURNS_TWICE is safe even for -ffreestanding. */
620 if (! strcmp (tname
, "setjmp")
621 || ! strcmp (tname
, "sigsetjmp")
622 || ! strcmp (name
, "savectx")
623 || ! strcmp (name
, "vfork")
624 || ! strcmp (name
, "getcontext"))
625 flags
|= ECF_RETURNS_TWICE
;
628 if (DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
629 && ALLOCA_FUNCTION_CODE_P (DECL_FUNCTION_CODE (fndecl
)))
630 flags
|= ECF_MAY_BE_ALLOCA
;
635 /* Similar to special_function_p; return a set of ERF_ flags for the
638 decl_return_flags (tree fndecl
)
641 tree type
= TREE_TYPE (fndecl
);
645 attr
= lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type
));
649 attr
= TREE_VALUE (TREE_VALUE (attr
));
650 if (!attr
|| TREE_STRING_LENGTH (attr
) < 1)
653 switch (TREE_STRING_POINTER (attr
)[0])
659 return ERF_RETURNS_ARG
| (TREE_STRING_POINTER (attr
)[0] - '1');
670 /* Return nonzero when FNDECL represents a call to setjmp. */
673 setjmp_call_p (const_tree fndecl
)
675 if (DECL_IS_RETURNS_TWICE (fndecl
))
676 return ECF_RETURNS_TWICE
;
677 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
681 /* Return true if STMT may be an alloca call. */
684 gimple_maybe_alloca_call_p (const gimple
*stmt
)
688 if (!is_gimple_call (stmt
))
691 fndecl
= gimple_call_fndecl (stmt
);
692 if (fndecl
&& (special_function_p (fndecl
, 0) & ECF_MAY_BE_ALLOCA
))
698 /* Return true if STMT is a builtin alloca call. */
701 gimple_alloca_call_p (const gimple
*stmt
)
705 if (!is_gimple_call (stmt
))
708 fndecl
= gimple_call_fndecl (stmt
);
709 if (fndecl
&& fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
710 switch (DECL_FUNCTION_CODE (fndecl
))
712 CASE_BUILT_IN_ALLOCA
:
713 return gimple_call_num_args (stmt
) > 0;
721 /* Return true when exp contains a builtin alloca call. */
724 alloca_call_p (const_tree exp
)
727 if (TREE_CODE (exp
) == CALL_EXPR
728 && (fndecl
= get_callee_fndecl (exp
))
729 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
730 switch (DECL_FUNCTION_CODE (fndecl
))
732 CASE_BUILT_IN_ALLOCA
:
741 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
742 function. Return FALSE otherwise. */
745 is_tm_builtin (const_tree fndecl
)
750 if (decl_is_tm_clone (fndecl
))
753 if (DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
755 switch (DECL_FUNCTION_CODE (fndecl
))
757 case BUILT_IN_TM_COMMIT
:
758 case BUILT_IN_TM_COMMIT_EH
:
759 case BUILT_IN_TM_ABORT
:
760 case BUILT_IN_TM_IRREVOCABLE
:
761 case BUILT_IN_TM_GETTMCLONE_IRR
:
762 case BUILT_IN_TM_MEMCPY
:
763 case BUILT_IN_TM_MEMMOVE
:
764 case BUILT_IN_TM_MEMSET
:
765 CASE_BUILT_IN_TM_STORE (1):
766 CASE_BUILT_IN_TM_STORE (2):
767 CASE_BUILT_IN_TM_STORE (4):
768 CASE_BUILT_IN_TM_STORE (8):
769 CASE_BUILT_IN_TM_STORE (FLOAT
):
770 CASE_BUILT_IN_TM_STORE (DOUBLE
):
771 CASE_BUILT_IN_TM_STORE (LDOUBLE
):
772 CASE_BUILT_IN_TM_STORE (M64
):
773 CASE_BUILT_IN_TM_STORE (M128
):
774 CASE_BUILT_IN_TM_STORE (M256
):
775 CASE_BUILT_IN_TM_LOAD (1):
776 CASE_BUILT_IN_TM_LOAD (2):
777 CASE_BUILT_IN_TM_LOAD (4):
778 CASE_BUILT_IN_TM_LOAD (8):
779 CASE_BUILT_IN_TM_LOAD (FLOAT
):
780 CASE_BUILT_IN_TM_LOAD (DOUBLE
):
781 CASE_BUILT_IN_TM_LOAD (LDOUBLE
):
782 CASE_BUILT_IN_TM_LOAD (M64
):
783 CASE_BUILT_IN_TM_LOAD (M128
):
784 CASE_BUILT_IN_TM_LOAD (M256
):
785 case BUILT_IN_TM_LOG
:
786 case BUILT_IN_TM_LOG_1
:
787 case BUILT_IN_TM_LOG_2
:
788 case BUILT_IN_TM_LOG_4
:
789 case BUILT_IN_TM_LOG_8
:
790 case BUILT_IN_TM_LOG_FLOAT
:
791 case BUILT_IN_TM_LOG_DOUBLE
:
792 case BUILT_IN_TM_LOG_LDOUBLE
:
793 case BUILT_IN_TM_LOG_M64
:
794 case BUILT_IN_TM_LOG_M128
:
795 case BUILT_IN_TM_LOG_M256
:
804 /* Detect flags (function attributes) from the function decl or type node. */
807 flags_from_decl_or_type (const_tree exp
)
813 /* The function exp may have the `malloc' attribute. */
814 if (DECL_IS_MALLOC (exp
))
817 /* The function exp may have the `returns_twice' attribute. */
818 if (DECL_IS_RETURNS_TWICE (exp
))
819 flags
|= ECF_RETURNS_TWICE
;
821 /* Process the pure and const attributes. */
822 if (TREE_READONLY (exp
))
824 if (DECL_PURE_P (exp
))
826 if (DECL_LOOPING_CONST_OR_PURE_P (exp
))
827 flags
|= ECF_LOOPING_CONST_OR_PURE
;
829 if (DECL_IS_NOVOPS (exp
))
831 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp
)))
833 if (lookup_attribute ("cold", DECL_ATTRIBUTES (exp
)))
836 if (TREE_NOTHROW (exp
))
837 flags
|= ECF_NOTHROW
;
841 if (is_tm_builtin (exp
))
842 flags
|= ECF_TM_BUILTIN
;
843 else if ((flags
& (ECF_CONST
|ECF_NOVOPS
)) != 0
844 || lookup_attribute ("transaction_pure",
845 TYPE_ATTRIBUTES (TREE_TYPE (exp
))))
846 flags
|= ECF_TM_PURE
;
849 flags
= special_function_p (exp
, flags
);
851 else if (TYPE_P (exp
))
853 if (TYPE_READONLY (exp
))
857 && ((flags
& ECF_CONST
) != 0
858 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp
))))
859 flags
|= ECF_TM_PURE
;
864 if (TREE_THIS_VOLATILE (exp
))
866 flags
|= ECF_NORETURN
;
867 if (flags
& (ECF_CONST
|ECF_PURE
))
868 flags
|= ECF_LOOPING_CONST_OR_PURE
;
874 /* Detect flags from a CALL_EXPR. */
877 call_expr_flags (const_tree t
)
880 tree decl
= get_callee_fndecl (t
);
883 flags
= flags_from_decl_or_type (decl
);
884 else if (CALL_EXPR_FN (t
) == NULL_TREE
)
885 flags
= internal_fn_flags (CALL_EXPR_IFN (t
));
888 tree type
= TREE_TYPE (CALL_EXPR_FN (t
));
889 if (type
&& TREE_CODE (type
) == POINTER_TYPE
)
890 flags
= flags_from_decl_or_type (TREE_TYPE (type
));
893 if (CALL_EXPR_BY_DESCRIPTOR (t
))
894 flags
|= ECF_BY_DESCRIPTOR
;
900 /* Return true if TYPE should be passed by invisible reference. */
903 pass_by_reference (CUMULATIVE_ARGS
*ca
, machine_mode mode
,
904 tree type
, bool named_arg
)
908 /* If this type contains non-trivial constructors, then it is
909 forbidden for the middle-end to create any new copies. */
910 if (TREE_ADDRESSABLE (type
))
913 /* GCC post 3.4 passes *all* variable sized types by reference. */
914 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
917 /* If a record type should be passed the same as its first (and only)
918 member, use the type and mode of that member. */
919 if (TREE_CODE (type
) == RECORD_TYPE
&& TYPE_TRANSPARENT_AGGR (type
))
921 type
= TREE_TYPE (first_field (type
));
922 mode
= TYPE_MODE (type
);
926 return targetm
.calls
.pass_by_reference (pack_cumulative_args (ca
), mode
,
930 /* Return true if TYPE should be passed by reference when passed to
931 the "..." arguments of a function. */
934 pass_va_arg_by_reference (tree type
)
936 return pass_by_reference (NULL
, TYPE_MODE (type
), type
, false);
939 /* Return true if TYPE, which is passed by reference, should be callee
940 copied instead of caller copied. */
943 reference_callee_copied (CUMULATIVE_ARGS
*ca
, machine_mode mode
,
944 tree type
, bool named_arg
)
946 if (type
&& TREE_ADDRESSABLE (type
))
948 return targetm
.calls
.callee_copies (pack_cumulative_args (ca
), mode
, type
,
953 /* Precompute all register parameters as described by ARGS, storing values
954 into fields within the ARGS array.
956 NUM_ACTUALS indicates the total number elements in the ARGS array.
958 Set REG_PARM_SEEN if we encounter a register parameter. */
961 precompute_register_parameters (int num_actuals
, struct arg_data
*args
,
968 for (i
= 0; i
< num_actuals
; i
++)
969 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
973 if (args
[i
].value
== 0)
976 args
[i
].value
= expand_normal (args
[i
].tree_value
);
977 preserve_temp_slots (args
[i
].value
);
981 /* If we are to promote the function arg to a wider mode,
984 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
986 = convert_modes (args
[i
].mode
,
987 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
988 args
[i
].value
, args
[i
].unsignedp
);
990 /* If the value is a non-legitimate constant, force it into a
991 pseudo now. TLS symbols sometimes need a call to resolve. */
992 if (CONSTANT_P (args
[i
].value
)
993 && !targetm
.legitimate_constant_p (args
[i
].mode
, args
[i
].value
))
994 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
996 /* If we're going to have to load the value by parts, pull the
997 parts into pseudos. The part extraction process can involve
998 non-trivial computation. */
999 if (GET_CODE (args
[i
].reg
) == PARALLEL
)
1001 tree type
= TREE_TYPE (args
[i
].tree_value
);
1002 args
[i
].parallel_value
1003 = emit_group_load_into_temps (args
[i
].reg
, args
[i
].value
,
1004 type
, int_size_in_bytes (type
));
1007 /* If the value is expensive, and we are inside an appropriately
1008 short loop, put the value into a pseudo and then put the pseudo
1011 For small register classes, also do this if this call uses
1012 register parameters. This is to avoid reload conflicts while
1013 loading the parameters registers. */
1015 else if ((! (REG_P (args
[i
].value
)
1016 || (GET_CODE (args
[i
].value
) == SUBREG
1017 && REG_P (SUBREG_REG (args
[i
].value
)))))
1018 && args
[i
].mode
!= BLKmode
1019 && (set_src_cost (args
[i
].value
, args
[i
].mode
,
1020 optimize_insn_for_speed_p ())
1021 > COSTS_N_INSNS (1))
1023 && targetm
.small_register_classes_for_mode_p (args
[i
].mode
))
1025 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
1029 #ifdef REG_PARM_STACK_SPACE
1031 /* The argument list is the property of the called routine and it
1032 may clobber it. If the fixed area has been used for previous
1033 parameters, we must save and restore it. */
1036 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
1041 /* Compute the boundary of the area that needs to be saved, if any. */
1042 high
= reg_parm_stack_space
;
1043 if (ARGS_GROW_DOWNWARD
)
1046 if (high
> highest_outgoing_arg_in_use
)
1047 high
= highest_outgoing_arg_in_use
;
1049 for (low
= 0; low
< high
; low
++)
1050 if (stack_usage_map
[low
] != 0 || low
>= stack_usage_watermark
)
1053 machine_mode save_mode
;
1059 while (stack_usage_map
[--high
] == 0)
1063 *high_to_save
= high
;
1065 num_to_save
= high
- low
+ 1;
1067 /* If we don't have the required alignment, must do this
1069 scalar_int_mode imode
;
1070 if (int_mode_for_size (num_to_save
* BITS_PER_UNIT
, 1).exists (&imode
)
1071 && (low
& (MIN (GET_MODE_SIZE (imode
),
1072 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)) == 0)
1075 save_mode
= BLKmode
;
1077 if (ARGS_GROW_DOWNWARD
)
1082 addr
= plus_constant (Pmode
, argblock
, delta
);
1083 stack_area
= gen_rtx_MEM (save_mode
, memory_address (save_mode
, addr
));
1085 set_mem_align (stack_area
, PARM_BOUNDARY
);
1086 if (save_mode
== BLKmode
)
1088 save_area
= assign_stack_temp (BLKmode
, num_to_save
);
1089 emit_block_move (validize_mem (save_area
), stack_area
,
1090 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
1094 save_area
= gen_reg_rtx (save_mode
);
1095 emit_move_insn (save_area
, stack_area
);
1105 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
1107 machine_mode save_mode
= GET_MODE (save_area
);
1109 rtx addr
, stack_area
;
1111 if (ARGS_GROW_DOWNWARD
)
1112 delta
= -high_to_save
;
1114 delta
= low_to_save
;
1116 addr
= plus_constant (Pmode
, argblock
, delta
);
1117 stack_area
= gen_rtx_MEM (save_mode
, memory_address (save_mode
, addr
));
1118 set_mem_align (stack_area
, PARM_BOUNDARY
);
1120 if (save_mode
!= BLKmode
)
1121 emit_move_insn (stack_area
, save_area
);
1123 emit_block_move (stack_area
, validize_mem (save_area
),
1124 GEN_INT (high_to_save
- low_to_save
+ 1),
1125 BLOCK_OP_CALL_PARM
);
1127 #endif /* REG_PARM_STACK_SPACE */
1129 /* If any elements in ARGS refer to parameters that are to be passed in
1130 registers, but not in memory, and whose alignment does not permit a
1131 direct copy into registers. Copy the values into a group of pseudos
1132 which we will later copy into the appropriate hard registers.
1134 Pseudos for each unaligned argument will be stored into the array
1135 args[argnum].aligned_regs. The caller is responsible for deallocating
1136 the aligned_regs array if it is nonzero. */
1139 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
1143 for (i
= 0; i
< num_actuals
; i
++)
1144 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
1145 && GET_CODE (args
[i
].reg
) != PARALLEL
1146 && args
[i
].mode
== BLKmode
1147 && MEM_P (args
[i
].value
)
1148 && (MEM_ALIGN (args
[i
].value
)
1149 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
1151 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1152 int endian_correction
= 0;
1154 if (args
[i
].partial
)
1156 gcc_assert (args
[i
].partial
% UNITS_PER_WORD
== 0);
1157 args
[i
].n_aligned_regs
= args
[i
].partial
/ UNITS_PER_WORD
;
1161 args
[i
].n_aligned_regs
1162 = (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
1165 args
[i
].aligned_regs
= XNEWVEC (rtx
, args
[i
].n_aligned_regs
);
1167 /* Structures smaller than a word are normally aligned to the
1168 least significant byte. On a BYTES_BIG_ENDIAN machine,
1169 this means we must skip the empty high order bytes when
1170 calculating the bit offset. */
1171 if (bytes
< UNITS_PER_WORD
1172 #ifdef BLOCK_REG_PADDING
1173 && (BLOCK_REG_PADDING (args
[i
].mode
,
1174 TREE_TYPE (args
[i
].tree_value
), 1)
1180 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
1182 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1184 rtx reg
= gen_reg_rtx (word_mode
);
1185 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
1186 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
1188 args
[i
].aligned_regs
[j
] = reg
;
1189 word
= extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
1190 word_mode
, word_mode
, false, NULL
);
1192 /* There is no need to restrict this code to loading items
1193 in TYPE_ALIGN sized hunks. The bitfield instructions can
1194 load up entire word sized registers efficiently.
1196 ??? This may not be needed anymore.
1197 We use to emit a clobber here but that doesn't let later
1198 passes optimize the instructions we emit. By storing 0 into
1199 the register later passes know the first AND to zero out the
1200 bitfield being set in the register is unnecessary. The store
1201 of 0 will be deleted as will at least the first AND. */
1203 emit_move_insn (reg
, const0_rtx
);
1205 bytes
-= bitsize
/ BITS_PER_UNIT
;
1206 store_bit_field (reg
, bitsize
, endian_correction
, 0, 0,
1207 word_mode
, word
, false);
1212 /* The limit set by -Walloc-larger-than=. */
1213 static GTY(()) tree alloc_object_size_limit
;
1215 /* Initialize ALLOC_OBJECT_SIZE_LIMIT based on the -Walloc-size-larger-than=
1216 setting if the option is specified, or to the maximum object size if it
1217 is not. Return the initialized value. */
1220 alloc_max_size (void)
1222 if (alloc_object_size_limit
)
1223 return alloc_object_size_limit
;
1225 HOST_WIDE_INT limit
= warn_alloc_size_limit
;
1226 if (limit
== HOST_WIDE_INT_MAX
)
1227 limit
= tree_to_shwi (TYPE_MAX_VALUE (ptrdiff_type_node
));
1229 alloc_object_size_limit
= build_int_cst (size_type_node
, limit
);
1231 return alloc_object_size_limit
;
1234 /* Return true when EXP's range can be determined and set RANGE[] to it
1235 after adjusting it if necessary to make EXP a represents a valid size
1236 of object, or a valid size argument to an allocation function declared
1237 with attribute alloc_size (whose argument may be signed), or to a string
1238 manipulation function like memset. When ALLOW_ZERO is true, allow
1239 returning a range of [0, 0] for a size in an anti-range [1, N] where
1240 N > PTRDIFF_MAX. A zero range is a (nearly) invalid argument to
1241 allocation functions like malloc but it is a valid argument to
1242 functions like memset. */
1245 get_size_range (tree exp
, tree range
[2], bool allow_zero
/* = false */)
1247 if (tree_fits_uhwi_p (exp
))
1249 /* EXP is a constant. */
1250 range
[0] = range
[1] = exp
;
1254 tree exptype
= TREE_TYPE (exp
);
1255 bool integral
= INTEGRAL_TYPE_P (exptype
);
1258 enum value_range_kind range_type
;
1261 range_type
= determine_value_range (exp
, &min
, &max
);
1263 range_type
= VR_VARYING
;
1265 if (range_type
== VR_VARYING
)
1269 /* Use the full range of the type of the expression when
1270 no value range information is available. */
1271 range
[0] = TYPE_MIN_VALUE (exptype
);
1272 range
[1] = TYPE_MAX_VALUE (exptype
);
1276 range
[0] = NULL_TREE
;
1277 range
[1] = NULL_TREE
;
1281 unsigned expprec
= TYPE_PRECISION (exptype
);
1283 bool signed_p
= !TYPE_UNSIGNED (exptype
);
1285 if (range_type
== VR_ANTI_RANGE
)
1289 if (wi::les_p (max
, 0))
1291 /* EXP is not in a strictly negative range. That means
1292 it must be in some (not necessarily strictly) positive
1293 range which includes zero. Since in signed to unsigned
1294 conversions negative values end up converted to large
1295 positive values, and otherwise they are not valid sizes,
1296 the resulting range is in both cases [0, TYPE_MAX]. */
1297 min
= wi::zero (expprec
);
1298 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1300 else if (wi::les_p (min
- 1, 0))
1302 /* EXP is not in a negative-positive range. That means EXP
1303 is either negative, or greater than max. Since negative
1304 sizes are invalid make the range [MAX + 1, TYPE_MAX]. */
1306 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1311 min
= wi::zero (expprec
);
1314 else if (wi::eq_p (0, min
- 1))
1316 /* EXP is unsigned and not in the range [1, MAX]. That means
1317 it's either zero or greater than MAX. Even though 0 would
1318 normally be detected by -Walloc-zero, unless ALLOW_ZERO
1319 is true, set the range to [MAX, TYPE_MAX] so that when MAX
1320 is greater than the limit the whole range is diagnosed. */
1322 min
= max
= wi::zero (expprec
);
1326 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1332 min
= wi::zero (expprec
);
1336 range
[0] = wide_int_to_tree (exptype
, min
);
1337 range
[1] = wide_int_to_tree (exptype
, max
);
1342 /* Diagnose a call EXP to function FN decorated with attribute alloc_size
1343 whose argument numbers given by IDX with values given by ARGS exceed
1344 the maximum object size or cause an unsigned oveflow (wrapping) when
1345 multiplied. FN is null when EXP is a call via a function pointer.
1346 When ARGS[0] is null the function does nothing. ARGS[1] may be null
1347 for functions like malloc, and non-null for those like calloc that
1348 are decorated with a two-argument attribute alloc_size. */
1351 maybe_warn_alloc_args_overflow (tree fn
, tree exp
, tree args
[2], int idx
[2])
1353 /* The range each of the (up to) two arguments is known to be in. */
1354 tree argrange
[2][2] = { { NULL_TREE
, NULL_TREE
}, { NULL_TREE
, NULL_TREE
} };
1356 /* Maximum object size set by -Walloc-size-larger-than= or SIZE_MAX / 2. */
1357 tree maxobjsize
= alloc_max_size ();
1359 location_t loc
= EXPR_LOCATION (exp
);
1361 tree fntype
= fn
? TREE_TYPE (fn
) : TREE_TYPE (TREE_TYPE (exp
));
1362 bool warned
= false;
1364 /* Validate each argument individually. */
1365 for (unsigned i
= 0; i
!= 2 && args
[i
]; ++i
)
1367 if (TREE_CODE (args
[i
]) == INTEGER_CST
)
1369 argrange
[i
][0] = args
[i
];
1370 argrange
[i
][1] = args
[i
];
1372 if (tree_int_cst_lt (args
[i
], integer_zero_node
))
1374 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1375 "%Kargument %i value %qE is negative",
1376 exp
, idx
[i
] + 1, args
[i
]);
1378 else if (integer_zerop (args
[i
]))
1380 /* Avoid issuing -Walloc-zero for allocation functions other
1381 than __builtin_alloca that are declared with attribute
1382 returns_nonnull because there's no portability risk. This
1383 avoids warning for such calls to libiberty's xmalloc and
1385 Also avoid issuing the warning for calls to function named
1387 if (fn
&& fndecl_built_in_p (fn
, BUILT_IN_ALLOCA
)
1388 ? IDENTIFIER_LENGTH (DECL_NAME (fn
)) != 6
1389 : !lookup_attribute ("returns_nonnull",
1390 TYPE_ATTRIBUTES (fntype
)))
1391 warned
= warning_at (loc
, OPT_Walloc_zero
,
1392 "%Kargument %i value is zero",
1395 else if (tree_int_cst_lt (maxobjsize
, args
[i
]))
1397 /* G++ emits calls to ::operator new[](SIZE_MAX) in C++98
1398 mode and with -fno-exceptions as a way to indicate array
1399 size overflow. There's no good way to detect C++98 here
1400 so avoid diagnosing these calls for all C++ modes. */
1405 && DECL_IS_OPERATOR_NEW_P (fn
)
1406 && integer_all_onesp (args
[i
]))
1409 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1410 "%Kargument %i value %qE exceeds "
1411 "maximum object size %E",
1412 exp
, idx
[i
] + 1, args
[i
], maxobjsize
);
1415 else if (TREE_CODE (args
[i
]) == SSA_NAME
1416 && get_size_range (args
[i
], argrange
[i
]))
1418 /* Verify that the argument's range is not negative (including
1419 upper bound of zero). */
1420 if (tree_int_cst_lt (argrange
[i
][0], integer_zero_node
)
1421 && tree_int_cst_le (argrange
[i
][1], integer_zero_node
))
1423 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1424 "%Kargument %i range [%E, %E] is negative",
1426 argrange
[i
][0], argrange
[i
][1]);
1428 else if (tree_int_cst_lt (maxobjsize
, argrange
[i
][0]))
1430 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1431 "%Kargument %i range [%E, %E] exceeds "
1432 "maximum object size %E",
1434 argrange
[i
][0], argrange
[i
][1],
1443 /* For a two-argument alloc_size, validate the product of the two
1444 arguments if both of their values or ranges are known. */
1445 if (!warned
&& tree_fits_uhwi_p (argrange
[0][0])
1446 && argrange
[1][0] && tree_fits_uhwi_p (argrange
[1][0])
1447 && !integer_onep (argrange
[0][0])
1448 && !integer_onep (argrange
[1][0]))
1450 /* Check for overflow in the product of a function decorated with
1451 attribute alloc_size (X, Y). */
1452 unsigned szprec
= TYPE_PRECISION (size_type_node
);
1453 wide_int x
= wi::to_wide (argrange
[0][0], szprec
);
1454 wide_int y
= wi::to_wide (argrange
[1][0], szprec
);
1456 wi::overflow_type vflow
;
1457 wide_int prod
= wi::umul (x
, y
, &vflow
);
1460 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1461 "%Kproduct %<%E * %E%> of arguments %i and %i "
1462 "exceeds %<SIZE_MAX%>",
1463 exp
, argrange
[0][0], argrange
[1][0],
1464 idx
[0] + 1, idx
[1] + 1);
1465 else if (wi::ltu_p (wi::to_wide (maxobjsize
, szprec
), prod
))
1466 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1467 "%Kproduct %<%E * %E%> of arguments %i and %i "
1468 "exceeds maximum object size %E",
1469 exp
, argrange
[0][0], argrange
[1][0],
1470 idx
[0] + 1, idx
[1] + 1,
1475 /* Print the full range of each of the two arguments to make
1476 it clear when it is, in fact, in a range and not constant. */
1477 if (argrange
[0][0] != argrange
[0][1])
1478 inform (loc
, "argument %i in the range [%E, %E]",
1479 idx
[0] + 1, argrange
[0][0], argrange
[0][1]);
1480 if (argrange
[1][0] != argrange
[1][1])
1481 inform (loc
, "argument %i in the range [%E, %E]",
1482 idx
[1] + 1, argrange
[1][0], argrange
[1][1]);
1488 location_t fnloc
= DECL_SOURCE_LOCATION (fn
);
1490 if (DECL_IS_BUILTIN (fn
))
1492 "in a call to built-in allocation function %qD", fn
);
1495 "in a call to allocation function %qD declared here", fn
);
1499 /* If EXPR refers to a character array or pointer declared attribute
1500 nonstring return a decl for that array or pointer and set *REF to
1501 the referenced enclosing object or pointer. Otherwise returns
1505 get_attr_nonstring_decl (tree expr
, tree
*ref
)
1508 tree var
= NULL_TREE
;
1509 if (TREE_CODE (decl
) == SSA_NAME
)
1511 gimple
*def
= SSA_NAME_DEF_STMT (decl
);
1513 if (is_gimple_assign (def
))
1515 tree_code code
= gimple_assign_rhs_code (def
);
1516 if (code
== ADDR_EXPR
1517 || code
== COMPONENT_REF
1518 || code
== VAR_DECL
)
1519 decl
= gimple_assign_rhs1 (def
);
1522 var
= SSA_NAME_VAR (decl
);
1525 if (TREE_CODE (decl
) == ADDR_EXPR
)
1526 decl
= TREE_OPERAND (decl
, 0);
1528 /* To simplify calling code, store the referenced DECL regardless of
1529 the attribute determined below, but avoid storing the SSA_NAME_VAR
1530 obtained above (it's not useful for dataflow purposes). */
1534 /* Use the SSA_NAME_VAR that was determined above to see if it's
1535 declared nonstring. Otherwise drill down into the referenced
1539 else if (TREE_CODE (decl
) == ARRAY_REF
)
1540 decl
= TREE_OPERAND (decl
, 0);
1541 else if (TREE_CODE (decl
) == COMPONENT_REF
)
1542 decl
= TREE_OPERAND (decl
, 1);
1543 else if (TREE_CODE (decl
) == MEM_REF
)
1544 return get_attr_nonstring_decl (TREE_OPERAND (decl
, 0), ref
);
1547 && lookup_attribute ("nonstring", DECL_ATTRIBUTES (decl
)))
1553 /* Warn about passing a non-string array/pointer to a function that
1554 expects a nul-terminated string argument. */
1557 maybe_warn_nonstring_arg (tree fndecl
, tree exp
)
1559 if (!fndecl
|| !fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
1562 if (TREE_NO_WARNING (exp
) || !warn_stringop_overflow
)
1565 /* Avoid clearly invalid calls (more checking done below). */
1566 unsigned nargs
= call_expr_nargs (exp
);
1570 /* The bound argument to a bounded string function like strncpy. */
1571 tree bound
= NULL_TREE
;
1573 /* The longest known or possible string argument to one of the comparison
1574 functions. If the length is less than the bound it is used instead.
1575 Since the length is only used for warning and not for code generation
1576 disable strict mode in the calls to get_range_strlen below. */
1577 tree maxlen
= NULL_TREE
;
1579 /* It's safe to call "bounded" string functions with a non-string
1580 argument since the functions provide an explicit bound for this
1581 purpose. The exception is strncat where the bound may refer to
1582 either the destination or the source. */
1583 int fncode
= DECL_FUNCTION_CODE (fndecl
);
1586 case BUILT_IN_STRCMP
:
1587 case BUILT_IN_STRNCMP
:
1588 case BUILT_IN_STRNCASECMP
:
1590 /* For these, if one argument refers to one or more of a set
1591 of string constants or arrays of known size, determine
1592 the range of their known or possible lengths and use it
1593 conservatively as the bound for the unbounded function,
1594 and to adjust the range of the bound of the bounded ones. */
1595 for (unsigned argno
= 0;
1596 argno
< MIN (nargs
, 2)
1597 && !(maxlen
&& TREE_CODE (maxlen
) == INTEGER_CST
); argno
++)
1599 tree arg
= CALL_EXPR_ARG (exp
, argno
);
1600 if (!get_attr_nonstring_decl (arg
))
1602 c_strlen_data lendata
= { };
1603 get_range_strlen (arg
, &lendata
, /* eltsize = */ 1);
1604 maxlen
= lendata
.maxbound
;
1610 case BUILT_IN_STRNCAT
:
1611 case BUILT_IN_STPNCPY
:
1612 case BUILT_IN_STRNCPY
:
1614 bound
= CALL_EXPR_ARG (exp
, 2);
1617 case BUILT_IN_STRNDUP
:
1619 bound
= CALL_EXPR_ARG (exp
, 1);
1622 case BUILT_IN_STRNLEN
:
1624 tree arg
= CALL_EXPR_ARG (exp
, 0);
1625 if (!get_attr_nonstring_decl (arg
))
1627 c_strlen_data lendata
= { };
1628 get_range_strlen (arg
, &lendata
, /* eltsize = */ 1);
1629 maxlen
= lendata
.maxbound
;
1632 bound
= CALL_EXPR_ARG (exp
, 1);
1640 /* Determine the range of the bound argument (if specified). */
1641 tree bndrng
[2] = { NULL_TREE
, NULL_TREE
};
1645 get_size_range (bound
, bndrng
);
1648 location_t loc
= EXPR_LOCATION (exp
);
1652 /* Diagnose excessive bound prior the adjustment below and
1653 regardless of attribute nonstring. */
1654 tree maxobjsize
= max_object_size ();
1655 if (tree_int_cst_lt (maxobjsize
, bndrng
[0]))
1657 if (tree_int_cst_equal (bndrng
[0], bndrng
[1]))
1658 warning_at (loc
, OPT_Wstringop_overflow_
,
1659 "%K%qD specified bound %E "
1660 "exceeds maximum object size %E",
1661 exp
, fndecl
, bndrng
[0], maxobjsize
);
1663 warning_at (loc
, OPT_Wstringop_overflow_
,
1664 "%K%qD specified bound [%E, %E] "
1665 "exceeds maximum object size %E",
1666 exp
, fndecl
, bndrng
[0], bndrng
[1], maxobjsize
);
1671 if (maxlen
&& !integer_all_onesp (maxlen
))
1673 /* Add one for the nul. */
1674 maxlen
= const_binop (PLUS_EXPR
, TREE_TYPE (maxlen
), maxlen
,
1679 /* Conservatively use the upper bound of the lengths for
1680 both the lower and the upper bound of the operation. */
1683 bound
= void_type_node
;
1687 /* Replace the bound on the operation with the upper bound
1688 of the length of the string if the latter is smaller. */
1689 if (tree_int_cst_lt (maxlen
, bndrng
[0]))
1691 else if (tree_int_cst_lt (maxlen
, bndrng
[1]))
1696 /* Iterate over the built-in function's formal arguments and check
1697 each const char* against the actual argument. If the actual
1698 argument is declared attribute non-string issue a warning unless
1699 the argument's maximum length is bounded. */
1700 function_args_iterator it
;
1701 function_args_iter_init (&it
, TREE_TYPE (fndecl
));
1703 for (unsigned argno
= 0; ; ++argno
, function_args_iter_next (&it
))
1705 /* Avoid iterating past the declared argument in a call
1706 to function declared without a prototype. */
1710 tree argtype
= function_args_iter_cond (&it
);
1714 if (TREE_CODE (argtype
) != POINTER_TYPE
)
1717 argtype
= TREE_TYPE (argtype
);
1719 if (TREE_CODE (argtype
) != INTEGER_TYPE
1720 || !TYPE_READONLY (argtype
))
1723 argtype
= TYPE_MAIN_VARIANT (argtype
);
1724 if (argtype
!= char_type_node
)
1727 tree callarg
= CALL_EXPR_ARG (exp
, argno
);
1728 if (TREE_CODE (callarg
) == ADDR_EXPR
)
1729 callarg
= TREE_OPERAND (callarg
, 0);
1731 /* See if the destination is declared with attribute "nonstring". */
1732 tree decl
= get_attr_nonstring_decl (callarg
);
1736 /* The maximum number of array elements accessed. */
1737 offset_int wibnd
= 0;
1739 if (argno
&& fncode
== BUILT_IN_STRNCAT
)
1741 /* See if the bound in strncat is derived from the length
1742 of the strlen of the destination (as it's expected to be).
1743 If so, reset BOUND and FNCODE to trigger a warning. */
1744 tree dstarg
= CALL_EXPR_ARG (exp
, 0);
1745 if (is_strlen_related_p (dstarg
, bound
))
1747 /* The bound applies to the destination, not to the source,
1748 so reset these to trigger a warning without mentioning
1754 /* Use the upper bound of the range for strncat. */
1755 wibnd
= wi::to_offset (bndrng
[1]);
1758 /* Use the lower bound of the range for functions other than
1760 wibnd
= wi::to_offset (bndrng
[0]);
1762 /* Determine the size of the argument array if it is one. */
1763 offset_int asize
= wibnd
;
1764 bool known_size
= false;
1765 tree type
= TREE_TYPE (decl
);
1767 /* Determine the array size. For arrays of unknown bound and
1768 pointers reset BOUND to trigger the appropriate warning. */
1769 if (TREE_CODE (type
) == ARRAY_TYPE
)
1771 if (tree arrbnd
= TYPE_DOMAIN (type
))
1773 if ((arrbnd
= TYPE_MAX_VALUE (arrbnd
)))
1775 asize
= wi::to_offset (arrbnd
) + 1;
1779 else if (bound
== void_type_node
)
1782 else if (bound
== void_type_node
)
1785 /* In a call to strncat with a bound in a range whose lower but
1786 not upper bound is less than the array size, reset ASIZE to
1787 be the same as the bound and the other variable to trigger
1788 the apprpriate warning below. */
1789 if (fncode
== BUILT_IN_STRNCAT
1790 && bndrng
[0] != bndrng
[1]
1791 && wi::ltu_p (wi::to_offset (bndrng
[0]), asize
)
1793 || wi::ltu_p (asize
, wibnd
)))
1800 bool warned
= false;
1802 auto_diagnostic_group d
;
1803 if (wi::ltu_p (asize
, wibnd
))
1805 if (bndrng
[0] == bndrng
[1])
1806 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1807 "%qD argument %i declared attribute "
1808 "%<nonstring%> is smaller than the specified "
1810 fndecl
, argno
+ 1, wibnd
.to_uhwi ());
1811 else if (wi::ltu_p (asize
, wi::to_offset (bndrng
[0])))
1812 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1813 "%qD argument %i declared attribute "
1814 "%<nonstring%> is smaller than "
1815 "the specified bound [%E, %E]",
1816 fndecl
, argno
+ 1, bndrng
[0], bndrng
[1]);
1818 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1819 "%qD argument %i declared attribute "
1820 "%<nonstring%> may be smaller than "
1821 "the specified bound [%E, %E]",
1822 fndecl
, argno
+ 1, bndrng
[0], bndrng
[1]);
1824 else if (fncode
== BUILT_IN_STRNCAT
)
1825 ; /* Avoid warning for calls to strncat() when the bound
1826 is equal to the size of the non-string argument. */
1828 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1829 "%qD argument %i declared attribute %<nonstring%>",
1833 inform (DECL_SOURCE_LOCATION (decl
),
1834 "argument %qD declared here", decl
);
1838 /* Issue an error if CALL_EXPR was flagged as requiring
1839 tall-call optimization. */
1842 maybe_complain_about_tail_call (tree call_expr
, const char *reason
)
1844 gcc_assert (TREE_CODE (call_expr
) == CALL_EXPR
);
1845 if (!CALL_EXPR_MUST_TAIL_CALL (call_expr
))
1848 error_at (EXPR_LOCATION (call_expr
), "cannot tail-call: %s", reason
);
1851 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1854 NUM_ACTUALS is the total number of parameters.
1856 N_NAMED_ARGS is the total number of named arguments.
1858 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1861 FNDECL is the tree code for the target of this call (if known)
1863 ARGS_SO_FAR holds state needed by the target to know where to place
1866 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1867 for arguments which are passed in registers.
1869 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1870 and may be modified by this routine.
1872 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1873 flags which may be modified by this routine.
1875 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1876 that requires allocation of stack space.
1878 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1879 the thunked-to function. */
1882 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
1883 struct arg_data
*args
,
1884 struct args_size
*args_size
,
1885 int n_named_args ATTRIBUTE_UNUSED
,
1886 tree exp
, tree struct_value_addr_value
,
1887 tree fndecl
, tree fntype
,
1888 cumulative_args_t args_so_far
,
1889 int reg_parm_stack_space
,
1890 rtx
*old_stack_level
,
1891 poly_int64_pod
*old_pending_adj
,
1892 int *must_preallocate
, int *ecf_flags
,
1893 bool *may_tailcall
, bool call_from_thunk_p
)
1895 CUMULATIVE_ARGS
*args_so_far_pnt
= get_cumulative_args (args_so_far
);
1896 location_t loc
= EXPR_LOCATION (exp
);
1898 /* Count arg position in order args appear. */
1903 args_size
->constant
= 0;
1906 bitmap_obstack_initialize (NULL
);
1908 /* In this loop, we consider args in the order they are written.
1909 We fill up ARGS from the back. */
1911 i
= num_actuals
- 1;
1914 call_expr_arg_iterator iter
;
1916 bitmap slots
= NULL
;
1918 if (struct_value_addr_value
)
1920 args
[j
].tree_value
= struct_value_addr_value
;
1924 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
1926 tree argtype
= TREE_TYPE (arg
);
1928 if (targetm
.calls
.split_complex_arg
1930 && TREE_CODE (argtype
) == COMPLEX_TYPE
1931 && targetm
.calls
.split_complex_arg (argtype
))
1933 tree subtype
= TREE_TYPE (argtype
);
1934 args
[j
].tree_value
= build1 (REALPART_EXPR
, subtype
, arg
);
1936 args
[j
].tree_value
= build1 (IMAGPART_EXPR
, subtype
, arg
);
1939 args
[j
].tree_value
= arg
;
1945 BITMAP_FREE (slots
);
1948 bitmap_obstack_release (NULL
);
1950 /* Extract attribute alloc_size from the type of the called expression
1951 (which could be a function or a function pointer) and if set, store
1952 the indices of the corresponding arguments in ALLOC_IDX, and then
1953 the actual argument(s) at those indices in ALLOC_ARGS. */
1954 int alloc_idx
[2] = { -1, -1 };
1955 if (tree alloc_size
= lookup_attribute ("alloc_size",
1956 TYPE_ATTRIBUTES (fntype
)))
1958 tree args
= TREE_VALUE (alloc_size
);
1959 alloc_idx
[0] = TREE_INT_CST_LOW (TREE_VALUE (args
)) - 1;
1960 if (TREE_CHAIN (args
))
1961 alloc_idx
[1] = TREE_INT_CST_LOW (TREE_VALUE (TREE_CHAIN (args
))) - 1;
1964 /* Array for up to the two attribute alloc_size arguments. */
1965 tree alloc_args
[] = { NULL_TREE
, NULL_TREE
};
1967 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1968 for (argpos
= 0; argpos
< num_actuals
; i
--, argpos
++)
1970 tree type
= TREE_TYPE (args
[i
].tree_value
);
1974 /* Replace erroneous argument with constant zero. */
1975 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1976 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1978 /* If TYPE is a transparent union or record, pass things the way
1979 we would pass the first field of the union or record. We have
1980 already verified that the modes are the same. */
1981 if ((TREE_CODE (type
) == UNION_TYPE
|| TREE_CODE (type
) == RECORD_TYPE
)
1982 && TYPE_TRANSPARENT_AGGR (type
))
1983 type
= TREE_TYPE (first_field (type
));
1985 /* Decide where to pass this arg.
1987 args[i].reg is nonzero if all or part is passed in registers.
1989 args[i].partial is nonzero if part but not all is passed in registers,
1990 and the exact value says how many bytes are passed in registers.
1992 args[i].pass_on_stack is nonzero if the argument must at least be
1993 computed on the stack. It may then be loaded back into registers
1994 if args[i].reg is nonzero.
1996 These decisions are driven by the FUNCTION_... macros and must agree
1997 with those made by function.c. */
1999 /* See if this argument should be passed by invisible reference. */
2000 if (pass_by_reference (args_so_far_pnt
, TYPE_MODE (type
),
2001 type
, argpos
< n_named_args
))
2004 tree base
= NULL_TREE
;
2007 = reference_callee_copied (args_so_far_pnt
, TYPE_MODE (type
),
2008 type
, argpos
< n_named_args
);
2010 /* If we're compiling a thunk, pass through invisible references
2011 instead of making a copy. */
2012 if (call_from_thunk_p
2014 && !TREE_ADDRESSABLE (type
)
2015 && (base
= get_base_address (args
[i
].tree_value
))
2016 && TREE_CODE (base
) != SSA_NAME
2017 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
)))))
2019 /* We may have turned the parameter value into an SSA name.
2020 Go back to the original parameter so we can take the
2022 if (TREE_CODE (args
[i
].tree_value
) == SSA_NAME
)
2024 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args
[i
].tree_value
));
2025 args
[i
].tree_value
= SSA_NAME_VAR (args
[i
].tree_value
);
2026 gcc_assert (TREE_CODE (args
[i
].tree_value
) == PARM_DECL
);
2028 /* Argument setup code may have copied the value to register. We
2029 revert that optimization now because the tail call code must
2030 use the original location. */
2031 if (TREE_CODE (args
[i
].tree_value
) == PARM_DECL
2032 && !MEM_P (DECL_RTL (args
[i
].tree_value
))
2033 && DECL_INCOMING_RTL (args
[i
].tree_value
)
2034 && MEM_P (DECL_INCOMING_RTL (args
[i
].tree_value
)))
2035 set_decl_rtl (args
[i
].tree_value
,
2036 DECL_INCOMING_RTL (args
[i
].tree_value
));
2038 mark_addressable (args
[i
].tree_value
);
2040 /* We can't use sibcalls if a callee-copied argument is
2041 stored in the current function's frame. */
2042 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
2044 *may_tailcall
= false;
2045 maybe_complain_about_tail_call (exp
,
2046 "a callee-copied argument is"
2047 " stored in the current"
2048 " function's frame");
2051 args
[i
].tree_value
= build_fold_addr_expr_loc (loc
,
2052 args
[i
].tree_value
);
2053 type
= TREE_TYPE (args
[i
].tree_value
);
2055 if (*ecf_flags
& ECF_CONST
)
2056 *ecf_flags
&= ~(ECF_CONST
| ECF_LOOPING_CONST_OR_PURE
);
2060 /* We make a copy of the object and pass the address to the
2061 function being called. */
2064 if (!COMPLETE_TYPE_P (type
)
2065 || TREE_CODE (TYPE_SIZE_UNIT (type
)) != INTEGER_CST
2066 || (flag_stack_check
== GENERIC_STACK_CHECK
2067 && compare_tree_int (TYPE_SIZE_UNIT (type
),
2068 STACK_CHECK_MAX_VAR_SIZE
) > 0))
2070 /* This is a variable-sized object. Make space on the stack
2072 rtx size_rtx
= expr_size (args
[i
].tree_value
);
2074 if (*old_stack_level
== 0)
2076 emit_stack_save (SAVE_BLOCK
, old_stack_level
);
2077 *old_pending_adj
= pending_stack_adjust
;
2078 pending_stack_adjust
= 0;
2081 /* We can pass TRUE as the 4th argument because we just
2082 saved the stack pointer and will restore it right after
2084 copy
= allocate_dynamic_stack_space (size_rtx
,
2087 max_int_size_in_bytes
2090 copy
= gen_rtx_MEM (BLKmode
, copy
);
2091 set_mem_attributes (copy
, type
, 1);
2094 copy
= assign_temp (type
, 1, 0);
2096 store_expr (args
[i
].tree_value
, copy
, 0, false, false);
2098 /* Just change the const function to pure and then let
2099 the next test clear the pure based on
2101 if (*ecf_flags
& ECF_CONST
)
2103 *ecf_flags
&= ~ECF_CONST
;
2104 *ecf_flags
|= ECF_PURE
;
2107 if (!callee_copies
&& *ecf_flags
& ECF_PURE
)
2108 *ecf_flags
&= ~(ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
2111 = build_fold_addr_expr_loc (loc
, make_tree (type
, copy
));
2112 type
= TREE_TYPE (args
[i
].tree_value
);
2113 *may_tailcall
= false;
2114 maybe_complain_about_tail_call (exp
,
2115 "argument must be passed"
2120 unsignedp
= TYPE_UNSIGNED (type
);
2121 mode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
2122 fndecl
? TREE_TYPE (fndecl
) : fntype
, 0);
2124 args
[i
].unsignedp
= unsignedp
;
2125 args
[i
].mode
= mode
;
2127 targetm
.calls
.warn_parameter_passing_abi (args_so_far
, type
);
2129 args
[i
].reg
= targetm
.calls
.function_arg (args_so_far
, mode
, type
,
2130 argpos
< n_named_args
);
2132 if (args
[i
].reg
&& CONST_INT_P (args
[i
].reg
))
2135 /* If this is a sibling call and the machine has register windows, the
2136 register window has to be unwinded before calling the routine, so
2137 arguments have to go into the incoming registers. */
2138 if (targetm
.calls
.function_incoming_arg
!= targetm
.calls
.function_arg
)
2139 args
[i
].tail_call_reg
2140 = targetm
.calls
.function_incoming_arg (args_so_far
, mode
, type
,
2141 argpos
< n_named_args
);
2143 args
[i
].tail_call_reg
= args
[i
].reg
;
2147 = targetm
.calls
.arg_partial_bytes (args_so_far
, mode
, type
,
2148 argpos
< n_named_args
);
2150 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (mode
, type
);
2152 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
2153 it means that we are to pass this arg in the register(s) designated
2154 by the PARALLEL, but also to pass it in the stack. */
2155 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
2156 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
2157 args
[i
].pass_on_stack
= 1;
2159 /* If this is an addressable type, we must preallocate the stack
2160 since we must evaluate the object into its final location.
2162 If this is to be passed in both registers and the stack, it is simpler
2164 if (TREE_ADDRESSABLE (type
)
2165 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
2166 *must_preallocate
= 1;
2168 /* Compute the stack-size of this argument. */
2169 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
2170 || reg_parm_stack_space
> 0
2171 || args
[i
].pass_on_stack
)
2172 locate_and_pad_parm (mode
, type
,
2173 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2178 reg_parm_stack_space
,
2179 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
2180 fndecl
, args_size
, &args
[i
].locate
);
2181 #ifdef BLOCK_REG_PADDING
2183 /* The argument is passed entirely in registers. See at which
2184 end it should be padded. */
2185 args
[i
].locate
.where_pad
=
2186 BLOCK_REG_PADDING (mode
, type
,
2187 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
2190 /* Update ARGS_SIZE, the total stack space for args so far. */
2192 args_size
->constant
+= args
[i
].locate
.size
.constant
;
2193 if (args
[i
].locate
.size
.var
)
2194 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
2196 /* Increment ARGS_SO_FAR, which has info about which arg-registers
2197 have been used, etc. */
2199 targetm
.calls
.function_arg_advance (args_so_far
, TYPE_MODE (type
),
2200 type
, argpos
< n_named_args
);
2202 /* Store argument values for functions decorated with attribute
2204 if (argpos
== alloc_idx
[0])
2205 alloc_args
[0] = args
[i
].tree_value
;
2206 else if (argpos
== alloc_idx
[1])
2207 alloc_args
[1] = args
[i
].tree_value
;
2212 /* Check the arguments of functions decorated with attribute
2214 maybe_warn_alloc_args_overflow (fndecl
, exp
, alloc_args
, alloc_idx
);
2217 /* Detect passing non-string arguments to functions expecting
2218 nul-terminated strings. */
2219 maybe_warn_nonstring_arg (fndecl
, exp
);
2222 /* Update ARGS_SIZE to contain the total size for the argument block.
2223 Return the original constant component of the argument block's size.
2225 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
2226 for arguments passed in registers. */
2229 compute_argument_block_size (int reg_parm_stack_space
,
2230 struct args_size
*args_size
,
2231 tree fndecl ATTRIBUTE_UNUSED
,
2232 tree fntype ATTRIBUTE_UNUSED
,
2233 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
2235 poly_int64 unadjusted_args_size
= args_size
->constant
;
2237 /* For accumulate outgoing args mode we don't need to align, since the frame
2238 will be already aligned. Align to STACK_BOUNDARY in order to prevent
2239 backends from generating misaligned frame sizes. */
2240 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
2241 preferred_stack_boundary
= STACK_BOUNDARY
;
2243 /* Compute the actual size of the argument block required. The variable
2244 and constant sizes must be combined, the size may have to be rounded,
2245 and there may be a minimum required size. */
2249 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
2250 args_size
->constant
= 0;
2252 preferred_stack_boundary
/= BITS_PER_UNIT
;
2253 if (preferred_stack_boundary
> 1)
2255 /* We don't handle this case yet. To handle it correctly we have
2256 to add the delta, round and subtract the delta.
2257 Currently no machine description requires this support. */
2258 gcc_assert (multiple_p (stack_pointer_delta
,
2259 preferred_stack_boundary
));
2260 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
2263 if (reg_parm_stack_space
> 0)
2266 = size_binop (MAX_EXPR
, args_size
->var
,
2267 ssize_int (reg_parm_stack_space
));
2269 /* The area corresponding to register parameters is not to count in
2270 the size of the block we need. So make the adjustment. */
2271 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2273 = size_binop (MINUS_EXPR
, args_size
->var
,
2274 ssize_int (reg_parm_stack_space
));
2279 preferred_stack_boundary
/= BITS_PER_UNIT
;
2280 if (preferred_stack_boundary
< 1)
2281 preferred_stack_boundary
= 1;
2282 args_size
->constant
= (aligned_upper_bound (args_size
->constant
2283 + stack_pointer_delta
,
2284 preferred_stack_boundary
)
2285 - stack_pointer_delta
);
2287 args_size
->constant
= upper_bound (args_size
->constant
,
2288 reg_parm_stack_space
);
2290 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2291 args_size
->constant
-= reg_parm_stack_space
;
2293 return unadjusted_args_size
;
2296 /* Precompute parameters as needed for a function call.
2298 FLAGS is mask of ECF_* constants.
2300 NUM_ACTUALS is the number of arguments.
2302 ARGS is an array containing information for each argument; this
2303 routine fills in the INITIAL_VALUE and VALUE fields for each
2304 precomputed argument. */
2307 precompute_arguments (int num_actuals
, struct arg_data
*args
)
2311 /* If this is a libcall, then precompute all arguments so that we do not
2312 get extraneous instructions emitted as part of the libcall sequence. */
2314 /* If we preallocated the stack space, and some arguments must be passed
2315 on the stack, then we must precompute any parameter which contains a
2316 function call which will store arguments on the stack.
2317 Otherwise, evaluating the parameter may clobber previous parameters
2318 which have already been stored into the stack. (we have code to avoid
2319 such case by saving the outgoing stack arguments, but it results in
2321 if (!ACCUMULATE_OUTGOING_ARGS
)
2324 for (i
= 0; i
< num_actuals
; i
++)
2329 if (TREE_CODE (args
[i
].tree_value
) != CALL_EXPR
)
2332 /* If this is an addressable type, we cannot pre-evaluate it. */
2333 type
= TREE_TYPE (args
[i
].tree_value
);
2334 gcc_assert (!TREE_ADDRESSABLE (type
));
2336 args
[i
].initial_value
= args
[i
].value
2337 = expand_normal (args
[i
].tree_value
);
2339 mode
= TYPE_MODE (type
);
2340 if (mode
!= args
[i
].mode
)
2342 int unsignedp
= args
[i
].unsignedp
;
2344 = convert_modes (args
[i
].mode
, mode
,
2345 args
[i
].value
, args
[i
].unsignedp
);
2347 /* CSE will replace this only if it contains args[i].value
2348 pseudo, so convert it down to the declared mode using
2350 if (REG_P (args
[i
].value
)
2351 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
2352 && promote_mode (type
, mode
, &unsignedp
) != args
[i
].mode
)
2354 args
[i
].initial_value
2355 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
2356 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
2357 SUBREG_PROMOTED_SET (args
[i
].initial_value
, args
[i
].unsignedp
);
2363 /* Given the current state of MUST_PREALLOCATE and information about
2364 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
2365 compute and return the final value for MUST_PREALLOCATE. */
2368 finalize_must_preallocate (int must_preallocate
, int num_actuals
,
2369 struct arg_data
*args
, struct args_size
*args_size
)
2371 /* See if we have or want to preallocate stack space.
2373 If we would have to push a partially-in-regs parm
2374 before other stack parms, preallocate stack space instead.
2376 If the size of some parm is not a multiple of the required stack
2377 alignment, we must preallocate.
2379 If the total size of arguments that would otherwise create a copy in
2380 a temporary (such as a CALL) is more than half the total argument list
2381 size, preallocation is faster.
2383 Another reason to preallocate is if we have a machine (like the m88k)
2384 where stack alignment is required to be maintained between every
2385 pair of insns, not just when the call is made. However, we assume here
2386 that such machines either do not have push insns (and hence preallocation
2387 would occur anyway) or the problem is taken care of with
2390 if (! must_preallocate
)
2392 int partial_seen
= 0;
2393 poly_int64 copy_to_evaluate_size
= 0;
2396 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
2398 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
2400 else if (partial_seen
&& args
[i
].reg
== 0)
2401 must_preallocate
= 1;
2403 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
2404 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
2405 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
2406 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
2407 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
2408 copy_to_evaluate_size
2409 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
2412 if (maybe_ne (args_size
->constant
, 0)
2413 && maybe_ge (copy_to_evaluate_size
* 2, args_size
->constant
))
2414 must_preallocate
= 1;
2416 return must_preallocate
;
2419 /* If we preallocated stack space, compute the address of each argument
2420 and store it into the ARGS array.
2422 We need not ensure it is a valid memory address here; it will be
2423 validized when it is used.
2425 ARGBLOCK is an rtx for the address of the outgoing arguments. */
2428 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
2432 rtx arg_reg
= argblock
;
2434 poly_int64 arg_offset
= 0;
2436 if (GET_CODE (argblock
) == PLUS
)
2438 arg_reg
= XEXP (argblock
, 0);
2439 arg_offset
= rtx_to_poly_int64 (XEXP (argblock
, 1));
2442 for (i
= 0; i
< num_actuals
; i
++)
2444 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
2445 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
2447 unsigned int align
, boundary
;
2448 poly_uint64 units_on_stack
= 0;
2449 machine_mode partial_mode
= VOIDmode
;
2451 /* Skip this parm if it will not be passed on the stack. */
2452 if (! args
[i
].pass_on_stack
2454 && args
[i
].partial
== 0)
2457 if (TYPE_EMPTY_P (TREE_TYPE (args
[i
].tree_value
)))
2460 addr
= simplify_gen_binary (PLUS
, Pmode
, arg_reg
, offset
);
2461 addr
= plus_constant (Pmode
, addr
, arg_offset
);
2463 if (args
[i
].partial
!= 0)
2465 /* Only part of the parameter is being passed on the stack.
2466 Generate a simple memory reference of the correct size. */
2467 units_on_stack
= args
[i
].locate
.size
.constant
;
2468 poly_uint64 bits_on_stack
= units_on_stack
* BITS_PER_UNIT
;
2469 partial_mode
= int_mode_for_size (bits_on_stack
, 1).else_blk ();
2470 args
[i
].stack
= gen_rtx_MEM (partial_mode
, addr
);
2471 set_mem_size (args
[i
].stack
, units_on_stack
);
2475 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
2476 set_mem_attributes (args
[i
].stack
,
2477 TREE_TYPE (args
[i
].tree_value
), 1);
2479 align
= BITS_PER_UNIT
;
2480 boundary
= args
[i
].locate
.boundary
;
2481 poly_int64 offset_val
;
2482 if (args
[i
].locate
.where_pad
!= PAD_DOWNWARD
)
2484 else if (poly_int_rtx_p (offset
, &offset_val
))
2486 align
= least_bit_hwi (boundary
);
2487 unsigned int offset_align
2488 = known_alignment (offset_val
) * BITS_PER_UNIT
;
2489 if (offset_align
!= 0)
2490 align
= MIN (align
, offset_align
);
2492 set_mem_align (args
[i
].stack
, align
);
2494 addr
= simplify_gen_binary (PLUS
, Pmode
, arg_reg
, slot_offset
);
2495 addr
= plus_constant (Pmode
, addr
, arg_offset
);
2497 if (args
[i
].partial
!= 0)
2499 /* Only part of the parameter is being passed on the stack.
2500 Generate a simple memory reference of the correct size.
2502 args
[i
].stack_slot
= gen_rtx_MEM (partial_mode
, addr
);
2503 set_mem_size (args
[i
].stack_slot
, units_on_stack
);
2507 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
2508 set_mem_attributes (args
[i
].stack_slot
,
2509 TREE_TYPE (args
[i
].tree_value
), 1);
2511 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
2513 /* Function incoming arguments may overlap with sibling call
2514 outgoing arguments and we cannot allow reordering of reads
2515 from function arguments with stores to outgoing arguments
2516 of sibling calls. */
2517 set_mem_alias_set (args
[i
].stack
, 0);
2518 set_mem_alias_set (args
[i
].stack_slot
, 0);
2523 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
2524 in a call instruction.
2526 FNDECL is the tree node for the target function. For an indirect call
2527 FNDECL will be NULL_TREE.
2529 ADDR is the operand 0 of CALL_EXPR for this call. */
2532 rtx_for_function_call (tree fndecl
, tree addr
)
2536 /* Get the function to call, in the form of RTL. */
2539 if (!TREE_USED (fndecl
) && fndecl
!= current_function_decl
)
2540 TREE_USED (fndecl
) = 1;
2542 /* Get a SYMBOL_REF rtx for the function address. */
2543 funexp
= XEXP (DECL_RTL (fndecl
), 0);
2546 /* Generate an rtx (probably a pseudo-register) for the address. */
2549 funexp
= expand_normal (addr
);
2550 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
2555 /* Return the static chain for this function, if any. */
2558 rtx_for_static_chain (const_tree fndecl_or_type
, bool incoming_p
)
2560 if (DECL_P (fndecl_or_type
) && !DECL_STATIC_CHAIN (fndecl_or_type
))
2563 return targetm
.calls
.static_chain (fndecl_or_type
, incoming_p
);
2566 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
2569 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
2570 or NULL_RTX if none has been scanned yet. */
2571 rtx_insn
*scan_start
;
2572 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
2573 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
2574 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
2575 with fixed offset, or PC if this is with variable or unknown offset. */
2577 } internal_arg_pointer_exp_state
;
2579 static rtx
internal_arg_pointer_based_exp (const_rtx
, bool);
2581 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
2582 the tail call sequence, starting with first insn that hasn't been
2583 scanned yet, and note for each pseudo on the LHS whether it is based
2584 on crtl->args.internal_arg_pointer or not, and what offset from that
2585 that pointer it has. */
2588 internal_arg_pointer_based_exp_scan (void)
2590 rtx_insn
*insn
, *scan_start
= internal_arg_pointer_exp_state
.scan_start
;
2592 if (scan_start
== NULL_RTX
)
2593 insn
= get_insns ();
2595 insn
= NEXT_INSN (scan_start
);
2599 rtx set
= single_set (insn
);
2600 if (set
&& REG_P (SET_DEST (set
)) && !HARD_REGISTER_P (SET_DEST (set
)))
2603 unsigned int idx
= REGNO (SET_DEST (set
)) - FIRST_PSEUDO_REGISTER
;
2604 /* Punt on pseudos set multiple times. */
2605 if (idx
< internal_arg_pointer_exp_state
.cache
.length ()
2606 && (internal_arg_pointer_exp_state
.cache
[idx
]
2610 val
= internal_arg_pointer_based_exp (SET_SRC (set
), false);
2611 if (val
!= NULL_RTX
)
2613 if (idx
>= internal_arg_pointer_exp_state
.cache
.length ())
2614 internal_arg_pointer_exp_state
.cache
2615 .safe_grow_cleared (idx
+ 1);
2616 internal_arg_pointer_exp_state
.cache
[idx
] = val
;
2619 if (NEXT_INSN (insn
) == NULL_RTX
)
2621 insn
= NEXT_INSN (insn
);
2624 internal_arg_pointer_exp_state
.scan_start
= scan_start
;
2627 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
2628 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
2629 it with fixed offset, or PC if this is with variable or unknown offset.
2630 TOPLEVEL is true if the function is invoked at the topmost level. */
2633 internal_arg_pointer_based_exp (const_rtx rtl
, bool toplevel
)
2635 if (CONSTANT_P (rtl
))
2638 if (rtl
== crtl
->args
.internal_arg_pointer
)
2641 if (REG_P (rtl
) && HARD_REGISTER_P (rtl
))
2645 if (GET_CODE (rtl
) == PLUS
&& poly_int_rtx_p (XEXP (rtl
, 1), &offset
))
2647 rtx val
= internal_arg_pointer_based_exp (XEXP (rtl
, 0), toplevel
);
2648 if (val
== NULL_RTX
|| val
== pc_rtx
)
2650 return plus_constant (Pmode
, val
, offset
);
2653 /* When called at the topmost level, scan pseudo assignments in between the
2654 last scanned instruction in the tail call sequence and the latest insn
2655 in that sequence. */
2657 internal_arg_pointer_based_exp_scan ();
2661 unsigned int idx
= REGNO (rtl
) - FIRST_PSEUDO_REGISTER
;
2662 if (idx
< internal_arg_pointer_exp_state
.cache
.length ())
2663 return internal_arg_pointer_exp_state
.cache
[idx
];
2668 subrtx_iterator::array_type array
;
2669 FOR_EACH_SUBRTX (iter
, array
, rtl
, NONCONST
)
2671 const_rtx x
= *iter
;
2672 if (REG_P (x
) && internal_arg_pointer_based_exp (x
, false) != NULL_RTX
)
2675 iter
.skip_subrtxes ();
2681 /* Return true if SIZE bytes starting from address ADDR might overlap an
2682 already-clobbered argument area. This function is used to determine
2683 if we should give up a sibcall. */
2686 mem_might_overlap_already_clobbered_arg_p (rtx addr
, poly_uint64 size
)
2689 unsigned HOST_WIDE_INT start
, end
;
2692 if (bitmap_empty_p (stored_args_map
)
2693 && stored_args_watermark
== HOST_WIDE_INT_M1U
)
2695 val
= internal_arg_pointer_based_exp (addr
, true);
2696 if (val
== NULL_RTX
)
2698 else if (!poly_int_rtx_p (val
, &i
))
2701 if (known_eq (size
, 0U))
2704 if (STACK_GROWS_DOWNWARD
)
2705 i
-= crtl
->args
.pretend_args_size
;
2707 i
+= crtl
->args
.pretend_args_size
;
2709 if (ARGS_GROW_DOWNWARD
)
2712 /* We can ignore any references to the function's pretend args,
2713 which at this point would manifest as negative values of I. */
2714 if (known_le (i
, 0) && known_le (size
, poly_uint64 (-i
)))
2717 start
= maybe_lt (i
, 0) ? 0 : constant_lower_bound (i
);
2718 if (!(i
+ size
).is_constant (&end
))
2719 end
= HOST_WIDE_INT_M1U
;
2721 if (end
> stored_args_watermark
)
2724 end
= MIN (end
, SBITMAP_SIZE (stored_args_map
));
2725 for (unsigned HOST_WIDE_INT k
= start
; k
< end
; ++k
)
2726 if (bitmap_bit_p (stored_args_map
, k
))
2732 /* Do the register loads required for any wholly-register parms or any
2733 parms which are passed both on the stack and in a register. Their
2734 expressions were already evaluated.
2736 Mark all register-parms as living through the call, putting these USE
2737 insns in the CALL_INSN_FUNCTION_USAGE field.
2739 When IS_SIBCALL, perform the check_sibcall_argument_overlap
2740 checking, setting *SIBCALL_FAILURE if appropriate. */
2743 load_register_parameters (struct arg_data
*args
, int num_actuals
,
2744 rtx
*call_fusage
, int flags
, int is_sibcall
,
2745 int *sibcall_failure
)
2749 for (i
= 0; i
< num_actuals
; i
++)
2751 rtx reg
= ((flags
& ECF_SIBCALL
)
2752 ? args
[i
].tail_call_reg
: args
[i
].reg
);
2755 int partial
= args
[i
].partial
;
2757 poly_int64 size
= 0;
2758 HOST_WIDE_INT const_size
= 0;
2759 rtx_insn
*before_arg
= get_last_insn ();
2760 /* Set non-negative if we must move a word at a time, even if
2761 just one word (e.g, partial == 4 && mode == DFmode). Set
2762 to -1 if we just use a normal move insn. This value can be
2763 zero if the argument is a zero size structure. */
2765 if (GET_CODE (reg
) == PARALLEL
)
2769 gcc_assert (partial
% UNITS_PER_WORD
== 0);
2770 nregs
= partial
/ UNITS_PER_WORD
;
2772 else if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
)
2774 /* Variable-sized parameters should be described by a
2775 PARALLEL instead. */
2776 const_size
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
2777 gcc_assert (const_size
>= 0);
2778 nregs
= (const_size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
2782 size
= GET_MODE_SIZE (args
[i
].mode
);
2784 /* Handle calls that pass values in multiple non-contiguous
2785 locations. The Irix 6 ABI has examples of this. */
2787 if (GET_CODE (reg
) == PARALLEL
)
2788 emit_group_move (reg
, args
[i
].parallel_value
);
2790 /* If simple case, just do move. If normal partial, store_one_arg
2791 has already loaded the register for us. In all other cases,
2792 load the register(s) from memory. */
2794 else if (nregs
== -1)
2796 emit_move_insn (reg
, args
[i
].value
);
2797 #ifdef BLOCK_REG_PADDING
2798 /* Handle case where we have a value that needs shifting
2799 up to the msb. eg. a QImode value and we're padding
2800 upward on a BYTES_BIG_ENDIAN machine. */
2801 if (args
[i
].locate
.where_pad
2802 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
))
2804 gcc_checking_assert (ordered_p (size
, UNITS_PER_WORD
));
2805 if (maybe_lt (size
, UNITS_PER_WORD
))
2809 = (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2811 /* Assigning REG here rather than a temp makes
2812 CALL_FUSAGE report the whole reg as used.
2813 Strictly speaking, the call only uses SIZE
2814 bytes at the msb end, but it doesn't seem worth
2815 generating rtl to say that. */
2816 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
2817 x
= expand_shift (LSHIFT_EXPR
, word_mode
,
2818 reg
, shift
, reg
, 1);
2820 emit_move_insn (reg
, x
);
2826 /* If we have pre-computed the values to put in the registers in
2827 the case of non-aligned structures, copy them in now. */
2829 else if (args
[i
].n_aligned_regs
!= 0)
2830 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
2831 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
2832 args
[i
].aligned_regs
[j
]);
2834 else if (partial
== 0 || args
[i
].pass_on_stack
)
2836 /* SIZE and CONST_SIZE are 0 for partial arguments and
2837 the size of a BLKmode type otherwise. */
2838 gcc_checking_assert (known_eq (size
, const_size
));
2839 rtx mem
= validize_mem (copy_rtx (args
[i
].value
));
2841 /* Check for overlap with already clobbered argument area,
2842 providing that this has non-zero size. */
2845 && (mem_might_overlap_already_clobbered_arg_p
2846 (XEXP (args
[i
].value
, 0), const_size
)))
2847 *sibcall_failure
= 1;
2849 if (const_size
% UNITS_PER_WORD
== 0
2850 || MEM_ALIGN (mem
) % BITS_PER_WORD
== 0)
2851 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
2855 move_block_to_reg (REGNO (reg
), mem
, nregs
- 1,
2857 rtx dest
= gen_rtx_REG (word_mode
, REGNO (reg
) + nregs
- 1);
2858 unsigned int bitoff
= (nregs
- 1) * BITS_PER_WORD
;
2859 unsigned int bitsize
= const_size
* BITS_PER_UNIT
- bitoff
;
2860 rtx x
= extract_bit_field (mem
, bitsize
, bitoff
, 1, dest
,
2861 word_mode
, word_mode
, false,
2863 if (BYTES_BIG_ENDIAN
)
2864 x
= expand_shift (LSHIFT_EXPR
, word_mode
, x
,
2865 BITS_PER_WORD
- bitsize
, dest
, 1);
2867 emit_move_insn (dest
, x
);
2870 /* Handle a BLKmode that needs shifting. */
2871 if (nregs
== 1 && const_size
< UNITS_PER_WORD
2872 #ifdef BLOCK_REG_PADDING
2873 && args
[i
].locate
.where_pad
== PAD_DOWNWARD
2879 rtx dest
= gen_rtx_REG (word_mode
, REGNO (reg
));
2880 int shift
= (UNITS_PER_WORD
- const_size
) * BITS_PER_UNIT
;
2881 enum tree_code dir
= (BYTES_BIG_ENDIAN
2882 ? RSHIFT_EXPR
: LSHIFT_EXPR
);
2885 x
= expand_shift (dir
, word_mode
, dest
, shift
, dest
, 1);
2887 emit_move_insn (dest
, x
);
2891 /* When a parameter is a block, and perhaps in other cases, it is
2892 possible that it did a load from an argument slot that was
2893 already clobbered. */
2895 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
2896 *sibcall_failure
= 1;
2898 /* Handle calls that pass values in multiple non-contiguous
2899 locations. The Irix 6 ABI has examples of this. */
2900 if (GET_CODE (reg
) == PARALLEL
)
2901 use_group_regs (call_fusage
, reg
);
2902 else if (nregs
== -1)
2903 use_reg_mode (call_fusage
, reg
,
2904 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)));
2906 use_regs (call_fusage
, REGNO (reg
), nregs
);
2911 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2912 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2913 bytes, then we would need to push some additional bytes to pad the
2914 arguments. So, we try to compute an adjust to the stack pointer for an
2915 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2916 bytes. Then, when the arguments are pushed the stack will be perfectly
2919 Return true if this optimization is possible, storing the adjustment
2920 in ADJUSTMENT_OUT and setting ARGS_SIZE->CONSTANT to the number of
2921 bytes that should be popped after the call. */
2924 combine_pending_stack_adjustment_and_call (poly_int64_pod
*adjustment_out
,
2925 poly_int64 unadjusted_args_size
,
2926 struct args_size
*args_size
,
2927 unsigned int preferred_unit_stack_boundary
)
2929 /* The number of bytes to pop so that the stack will be
2930 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2931 poly_int64 adjustment
;
2932 /* The alignment of the stack after the arguments are pushed, if we
2933 just pushed the arguments without adjust the stack here. */
2934 unsigned HOST_WIDE_INT unadjusted_alignment
;
2936 if (!known_misalignment (stack_pointer_delta
+ unadjusted_args_size
,
2937 preferred_unit_stack_boundary
,
2938 &unadjusted_alignment
))
2941 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2942 as possible -- leaving just enough left to cancel out the
2943 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2944 PENDING_STACK_ADJUST is non-negative, and congruent to
2945 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2947 /* Begin by trying to pop all the bytes. */
2948 unsigned HOST_WIDE_INT tmp_misalignment
;
2949 if (!known_misalignment (pending_stack_adjust
,
2950 preferred_unit_stack_boundary
,
2953 unadjusted_alignment
-= tmp_misalignment
;
2954 adjustment
= pending_stack_adjust
;
2955 /* Push enough additional bytes that the stack will be aligned
2956 after the arguments are pushed. */
2957 if (preferred_unit_stack_boundary
> 1 && unadjusted_alignment
)
2958 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
2960 /* We need to know whether the adjusted argument size
2961 (UNADJUSTED_ARGS_SIZE - ADJUSTMENT) constitutes an allocation
2962 or a deallocation. */
2963 if (!ordered_p (adjustment
, unadjusted_args_size
))
2966 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2967 bytes after the call. The right number is the entire
2968 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2969 by the arguments in the first place. */
2971 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
2973 *adjustment_out
= adjustment
;
2977 /* Scan X expression if it does not dereference any argument slots
2978 we already clobbered by tail call arguments (as noted in stored_args_map
2980 Return nonzero if X expression dereferences such argument slots,
2984 check_sibcall_argument_overlap_1 (rtx x
)
2993 code
= GET_CODE (x
);
2995 /* We need not check the operands of the CALL expression itself. */
3000 return (mem_might_overlap_already_clobbered_arg_p
3001 (XEXP (x
, 0), GET_MODE_SIZE (GET_MODE (x
))));
3003 /* Scan all subexpressions. */
3004 fmt
= GET_RTX_FORMAT (code
);
3005 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
3009 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
3012 else if (*fmt
== 'E')
3014 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
3015 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
3022 /* Scan sequence after INSN if it does not dereference any argument slots
3023 we already clobbered by tail call arguments (as noted in stored_args_map
3024 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
3025 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
3026 should be 0). Return nonzero if sequence after INSN dereferences such argument
3027 slots, zero otherwise. */
3030 check_sibcall_argument_overlap (rtx_insn
*insn
, struct arg_data
*arg
,
3031 int mark_stored_args_map
)
3033 poly_uint64 low
, high
;
3034 unsigned HOST_WIDE_INT const_low
, const_high
;
3036 if (insn
== NULL_RTX
)
3037 insn
= get_insns ();
3039 insn
= NEXT_INSN (insn
);
3041 for (; insn
; insn
= NEXT_INSN (insn
))
3043 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
3046 if (mark_stored_args_map
)
3048 if (ARGS_GROW_DOWNWARD
)
3049 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
3051 low
= arg
->locate
.slot_offset
.constant
;
3052 high
= low
+ arg
->locate
.size
.constant
;
3054 const_low
= constant_lower_bound (low
);
3055 if (high
.is_constant (&const_high
))
3056 for (unsigned HOST_WIDE_INT i
= const_low
; i
< const_high
; ++i
)
3057 bitmap_set_bit (stored_args_map
, i
);
3059 stored_args_watermark
= MIN (stored_args_watermark
, const_low
);
3061 return insn
!= NULL_RTX
;
3064 /* Given that a function returns a value of mode MODE at the most
3065 significant end of hard register VALUE, shift VALUE left or right
3066 as specified by LEFT_P. Return true if some action was needed. */
3069 shift_return_value (machine_mode mode
, bool left_p
, rtx value
)
3071 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
3072 machine_mode value_mode
= GET_MODE (value
);
3073 poly_int64 shift
= GET_MODE_BITSIZE (value_mode
) - GET_MODE_BITSIZE (mode
);
3075 if (known_eq (shift
, 0))
3078 /* Use ashr rather than lshr for right shifts. This is for the benefit
3079 of the MIPS port, which requires SImode values to be sign-extended
3080 when stored in 64-bit registers. */
3081 if (!force_expand_binop (value_mode
, left_p
? ashl_optab
: ashr_optab
,
3082 value
, gen_int_shift_amount (value_mode
, shift
),
3083 value
, 1, OPTAB_WIDEN
))
3088 /* If X is a likely-spilled register value, copy it to a pseudo
3089 register and return that register. Return X otherwise. */
3092 avoid_likely_spilled_reg (rtx x
)
3097 && HARD_REGISTER_P (x
)
3098 && targetm
.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x
))))
3100 /* Make sure that we generate a REG rather than a CONCAT.
3101 Moves into CONCATs can need nontrivial instructions,
3102 and the whole point of this function is to avoid
3103 using the hard register directly in such a situation. */
3104 generating_concat_p
= 0;
3105 new_rtx
= gen_reg_rtx (GET_MODE (x
));
3106 generating_concat_p
= 1;
3107 emit_move_insn (new_rtx
, x
);
3113 /* Helper function for expand_call.
3114 Return false is EXP is not implementable as a sibling call. */
3117 can_implement_as_sibling_call_p (tree exp
,
3118 rtx structure_value_addr
,
3120 int reg_parm_stack_space ATTRIBUTE_UNUSED
,
3124 const args_size
&args_size
)
3126 if (!targetm
.have_sibcall_epilogue ())
3128 maybe_complain_about_tail_call
3130 "machine description does not have"
3131 " a sibcall_epilogue instruction pattern");
3135 /* Doing sibling call optimization needs some work, since
3136 structure_value_addr can be allocated on the stack.
3137 It does not seem worth the effort since few optimizable
3138 sibling calls will return a structure. */
3139 if (structure_value_addr
!= NULL_RTX
)
3141 maybe_complain_about_tail_call (exp
, "callee returns a structure");
3145 #ifdef REG_PARM_STACK_SPACE
3146 /* If outgoing reg parm stack space changes, we cannot do sibcall. */
3147 if (OUTGOING_REG_PARM_STACK_SPACE (funtype
)
3148 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl
))
3149 || (reg_parm_stack_space
!= REG_PARM_STACK_SPACE (current_function_decl
)))
3151 maybe_complain_about_tail_call (exp
,
3152 "inconsistent size of stack space"
3153 " allocated for arguments which are"
3154 " passed in registers");
3159 /* Check whether the target is able to optimize the call
3161 if (!targetm
.function_ok_for_sibcall (fndecl
, exp
))
3163 maybe_complain_about_tail_call (exp
,
3164 "target is not able to optimize the"
3165 " call into a sibling call");
3169 /* Functions that do not return exactly once may not be sibcall
3171 if (flags
& ECF_RETURNS_TWICE
)
3173 maybe_complain_about_tail_call (exp
, "callee returns twice");
3176 if (flags
& ECF_NORETURN
)
3178 maybe_complain_about_tail_call (exp
, "callee does not return");
3182 if (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
))))
3184 maybe_complain_about_tail_call (exp
, "volatile function type");
3188 /* If the called function is nested in the current one, it might access
3189 some of the caller's arguments, but could clobber them beforehand if
3190 the argument areas are shared. */
3191 if (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
3193 maybe_complain_about_tail_call (exp
, "nested function");
3197 /* If this function requires more stack slots than the current
3198 function, we cannot change it into a sibling call.
3199 crtl->args.pretend_args_size is not part of the
3200 stack allocated by our caller. */
3201 if (maybe_gt (args_size
.constant
,
3202 crtl
->args
.size
- crtl
->args
.pretend_args_size
))
3204 maybe_complain_about_tail_call (exp
,
3205 "callee required more stack slots"
3206 " than the caller");
3210 /* If the callee pops its own arguments, then it must pop exactly
3211 the same number of arguments as the current function. */
3212 if (maybe_ne (targetm
.calls
.return_pops_args (fndecl
, funtype
,
3213 args_size
.constant
),
3214 targetm
.calls
.return_pops_args (current_function_decl
,
3216 (current_function_decl
),
3219 maybe_complain_about_tail_call (exp
,
3220 "inconsistent number of"
3221 " popped arguments");
3225 if (!lang_hooks
.decls
.ok_for_sibcall (fndecl
))
3227 maybe_complain_about_tail_call (exp
, "frontend does not support"
3232 /* All checks passed. */
3236 /* Update stack alignment when the parameter is passed in the stack
3237 since the outgoing parameter requires extra alignment on the calling
3241 update_stack_alignment_for_call (struct locate_and_pad_arg_data
*locate
)
3243 if (crtl
->stack_alignment_needed
< locate
->boundary
)
3244 crtl
->stack_alignment_needed
= locate
->boundary
;
3245 if (crtl
->preferred_stack_boundary
< locate
->boundary
)
3246 crtl
->preferred_stack_boundary
= locate
->boundary
;
3249 /* Generate all the code for a CALL_EXPR exp
3250 and return an rtx for its value.
3251 Store the value in TARGET (specified as an rtx) if convenient.
3252 If the value is stored in TARGET then TARGET is returned.
3253 If IGNORE is nonzero, then we ignore the value of the function call. */
3256 expand_call (tree exp
, rtx target
, int ignore
)
3258 /* Nonzero if we are currently expanding a call. */
3259 static int currently_expanding_call
= 0;
3261 /* RTX for the function to be called. */
3263 /* Sequence of insns to perform a normal "call". */
3264 rtx_insn
*normal_call_insns
= NULL
;
3265 /* Sequence of insns to perform a tail "call". */
3266 rtx_insn
*tail_call_insns
= NULL
;
3267 /* Data type of the function. */
3269 tree type_arg_types
;
3271 /* Declaration of the function being called,
3272 or 0 if the function is computed (not known by name). */
3274 /* The type of the function being called. */
3276 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
3277 bool must_tail_call
= CALL_EXPR_MUST_TAIL_CALL (exp
);
3280 /* Register in which non-BLKmode value will be returned,
3281 or 0 if no value or if value is BLKmode. */
3283 /* Address where we should return a BLKmode value;
3284 0 if value not BLKmode. */
3285 rtx structure_value_addr
= 0;
3286 /* Nonzero if that address is being passed by treating it as
3287 an extra, implicit first parameter. Otherwise,
3288 it is passed by being copied directly into struct_value_rtx. */
3289 int structure_value_addr_parm
= 0;
3290 /* Holds the value of implicit argument for the struct value. */
3291 tree structure_value_addr_value
= NULL_TREE
;
3292 /* Size of aggregate value wanted, or zero if none wanted
3293 or if we are using the non-reentrant PCC calling convention
3294 or expecting the value in registers. */
3295 poly_int64 struct_value_size
= 0;
3296 /* Nonzero if called function returns an aggregate in memory PCC style,
3297 by returning the address of where to find it. */
3298 int pcc_struct_value
= 0;
3299 rtx struct_value
= 0;
3301 /* Number of actual parameters in this call, including struct value addr. */
3303 /* Number of named args. Args after this are anonymous ones
3304 and they must all go on the stack. */
3306 /* Number of complex actual arguments that need to be split. */
3307 int num_complex_actuals
= 0;
3309 /* Vector of information about each argument.
3310 Arguments are numbered in the order they will be pushed,
3311 not the order they are written. */
3312 struct arg_data
*args
;
3314 /* Total size in bytes of all the stack-parms scanned so far. */
3315 struct args_size args_size
;
3316 struct args_size adjusted_args_size
;
3317 /* Size of arguments before any adjustments (such as rounding). */
3318 poly_int64 unadjusted_args_size
;
3319 /* Data on reg parms scanned so far. */
3320 CUMULATIVE_ARGS args_so_far_v
;
3321 cumulative_args_t args_so_far
;
3322 /* Nonzero if a reg parm has been scanned. */
3324 /* Nonzero if this is an indirect function call. */
3326 /* Nonzero if we must avoid push-insns in the args for this call.
3327 If stack space is allocated for register parameters, but not by the
3328 caller, then it is preallocated in the fixed part of the stack frame.
3329 So the entire argument block must then be preallocated (i.e., we
3330 ignore PUSH_ROUNDING in that case). */
3332 int must_preallocate
= !PUSH_ARGS
;
3334 /* Size of the stack reserved for parameter registers. */
3335 int reg_parm_stack_space
= 0;
3337 /* Address of space preallocated for stack parms
3338 (on machines that lack push insns), or 0 if space not preallocated. */
3341 /* Mask of ECF_ and ERF_ flags. */
3343 int return_flags
= 0;
3344 #ifdef REG_PARM_STACK_SPACE
3345 /* Define the boundary of the register parm stack space that needs to be
3347 int low_to_save
, high_to_save
;
3348 rtx save_area
= 0; /* Place that it is saved */
3351 unsigned int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3352 char *initial_stack_usage_map
= stack_usage_map
;
3353 unsigned HOST_WIDE_INT initial_stack_usage_watermark
= stack_usage_watermark
;
3354 char *stack_usage_map_buf
= NULL
;
3356 poly_int64 old_stack_allocated
;
3358 /* State variables to track stack modifications. */
3359 rtx old_stack_level
= 0;
3360 int old_stack_arg_under_construction
= 0;
3361 poly_int64 old_pending_adj
= 0;
3362 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3364 /* Some stack pointer alterations we make are performed via
3365 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
3366 which we then also need to save/restore along the way. */
3367 poly_int64 old_stack_pointer_delta
= 0;
3370 tree addr
= CALL_EXPR_FN (exp
);
3372 /* The alignment of the stack, in bits. */
3373 unsigned HOST_WIDE_INT preferred_stack_boundary
;
3374 /* The alignment of the stack, in bytes. */
3375 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
3376 /* The static chain value to use for this call. */
3377 rtx static_chain_value
;
3378 /* See if this is "nothrow" function call. */
3379 if (TREE_NOTHROW (exp
))
3380 flags
|= ECF_NOTHROW
;
3382 /* See if we can find a DECL-node for the actual function, and get the
3383 function attributes (flags) from the function decl or type node. */
3384 fndecl
= get_callee_fndecl (exp
);
3387 fntype
= TREE_TYPE (fndecl
);
3388 flags
|= flags_from_decl_or_type (fndecl
);
3389 return_flags
|= decl_return_flags (fndecl
);
3393 fntype
= TREE_TYPE (TREE_TYPE (addr
));
3394 flags
|= flags_from_decl_or_type (fntype
);
3395 if (CALL_EXPR_BY_DESCRIPTOR (exp
))
3396 flags
|= ECF_BY_DESCRIPTOR
;
3398 rettype
= TREE_TYPE (exp
);
3400 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
3402 /* Warn if this value is an aggregate type,
3403 regardless of which calling convention we are using for it. */
3404 if (AGGREGATE_TYPE_P (rettype
))
3405 warning (OPT_Waggregate_return
, "function call has aggregate value");
3407 /* If the result of a non looping pure or const function call is
3408 ignored (or void), and none of its arguments are volatile, we can
3409 avoid expanding the call and just evaluate the arguments for
3411 if ((flags
& (ECF_CONST
| ECF_PURE
))
3412 && (!(flags
& ECF_LOOPING_CONST_OR_PURE
))
3413 && (ignore
|| target
== const0_rtx
3414 || TYPE_MODE (rettype
) == VOIDmode
))
3416 bool volatilep
= false;
3418 call_expr_arg_iterator iter
;
3420 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3421 if (TREE_THIS_VOLATILE (arg
))
3429 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3430 expand_expr (arg
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
3435 #ifdef REG_PARM_STACK_SPACE
3436 reg_parm_stack_space
= REG_PARM_STACK_SPACE (!fndecl
? fntype
: fndecl
);
3439 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
3440 && reg_parm_stack_space
> 0 && PUSH_ARGS
)
3441 must_preallocate
= 1;
3443 /* Set up a place to return a structure. */
3445 /* Cater to broken compilers. */
3446 if (aggregate_value_p (exp
, fntype
))
3448 /* This call returns a big structure. */
3449 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
3451 #ifdef PCC_STATIC_STRUCT_RETURN
3453 pcc_struct_value
= 1;
3455 #else /* not PCC_STATIC_STRUCT_RETURN */
3457 if (!poly_int_tree_p (TYPE_SIZE_UNIT (rettype
), &struct_value_size
))
3458 struct_value_size
= -1;
3460 /* Even if it is semantically safe to use the target as the return
3461 slot, it may be not sufficiently aligned for the return type. */
3462 if (CALL_EXPR_RETURN_SLOT_OPT (exp
)
3465 /* If rettype is addressable, we may not create a temporary.
3466 If target is properly aligned at runtime and the compiler
3467 just doesn't know about it, it will work fine, otherwise it
3469 && (TREE_ADDRESSABLE (rettype
)
3470 || !(MEM_ALIGN (target
) < TYPE_ALIGN (rettype
)
3471 && targetm
.slow_unaligned_access (TYPE_MODE (rettype
),
3472 MEM_ALIGN (target
)))))
3473 structure_value_addr
= XEXP (target
, 0);
3476 /* For variable-sized objects, we must be called with a target
3477 specified. If we were to allocate space on the stack here,
3478 we would have no way of knowing when to free it. */
3479 rtx d
= assign_temp (rettype
, 1, 1);
3480 structure_value_addr
= XEXP (d
, 0);
3484 #endif /* not PCC_STATIC_STRUCT_RETURN */
3487 /* Figure out the amount to which the stack should be aligned. */
3488 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3491 struct cgraph_rtl_info
*i
= cgraph_node::rtl_info (fndecl
);
3492 /* Without automatic stack alignment, we can't increase preferred
3493 stack boundary. With automatic stack alignment, it is
3494 unnecessary since unless we can guarantee that all callers will
3495 align the outgoing stack properly, callee has to align its
3498 && i
->preferred_incoming_stack_boundary
3499 && i
->preferred_incoming_stack_boundary
< preferred_stack_boundary
)
3500 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
3503 /* Operand 0 is a pointer-to-function; get the type of the function. */
3504 funtype
= TREE_TYPE (addr
);
3505 gcc_assert (POINTER_TYPE_P (funtype
));
3506 funtype
= TREE_TYPE (funtype
);
3508 /* Count whether there are actual complex arguments that need to be split
3509 into their real and imaginary parts. Munge the type_arg_types
3510 appropriately here as well. */
3511 if (targetm
.calls
.split_complex_arg
)
3513 call_expr_arg_iterator iter
;
3515 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3517 tree type
= TREE_TYPE (arg
);
3518 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
3519 && targetm
.calls
.split_complex_arg (type
))
3520 num_complex_actuals
++;
3522 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
3525 type_arg_types
= TYPE_ARG_TYPES (funtype
);
3527 if (flags
& ECF_MAY_BE_ALLOCA
)
3528 cfun
->calls_alloca
= 1;
3530 /* If struct_value_rtx is 0, it means pass the address
3531 as if it were an extra parameter. Put the argument expression
3532 in structure_value_addr_value. */
3533 if (structure_value_addr
&& struct_value
== 0)
3535 /* If structure_value_addr is a REG other than
3536 virtual_outgoing_args_rtx, we can use always use it. If it
3537 is not a REG, we must always copy it into a register.
3538 If it is virtual_outgoing_args_rtx, we must copy it to another
3539 register in some cases. */
3540 rtx temp
= (!REG_P (structure_value_addr
)
3541 || (ACCUMULATE_OUTGOING_ARGS
3542 && stack_arg_under_construction
3543 && structure_value_addr
== virtual_outgoing_args_rtx
)
3544 ? copy_addr_to_reg (convert_memory_address
3545 (Pmode
, structure_value_addr
))
3546 : structure_value_addr
);
3548 structure_value_addr_value
=
3549 make_tree (build_pointer_type (TREE_TYPE (funtype
)), temp
);
3550 structure_value_addr_parm
= 1;
3553 /* Count the arguments and set NUM_ACTUALS. */
3555 call_expr_nargs (exp
) + num_complex_actuals
+ structure_value_addr_parm
;
3557 /* Compute number of named args.
3558 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
3560 if (type_arg_types
!= 0)
3562 = (list_length (type_arg_types
)
3563 /* Count the struct value address, if it is passed as a parm. */
3564 + structure_value_addr_parm
);
3566 /* If we know nothing, treat all args as named. */
3567 n_named_args
= num_actuals
;
3569 /* Start updating where the next arg would go.
3571 On some machines (such as the PA) indirect calls have a different
3572 calling convention than normal calls. The fourth argument in
3573 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
3575 INIT_CUMULATIVE_ARGS (args_so_far_v
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
3576 args_so_far
= pack_cumulative_args (&args_so_far_v
);
3578 /* Now possibly adjust the number of named args.
3579 Normally, don't include the last named arg if anonymous args follow.
3580 We do include the last named arg if
3581 targetm.calls.strict_argument_naming() returns nonzero.
3582 (If no anonymous args follow, the result of list_length is actually
3583 one too large. This is harmless.)
3585 If targetm.calls.pretend_outgoing_varargs_named() returns
3586 nonzero, and targetm.calls.strict_argument_naming() returns zero,
3587 this machine will be able to place unnamed args that were passed
3588 in registers into the stack. So treat all args as named. This
3589 allows the insns emitting for a specific argument list to be
3590 independent of the function declaration.
3592 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
3593 we do not have any reliable way to pass unnamed args in
3594 registers, so we must force them into memory. */
3596 if (type_arg_types
!= 0
3597 && targetm
.calls
.strict_argument_naming (args_so_far
))
3599 else if (type_arg_types
!= 0
3600 && ! targetm
.calls
.pretend_outgoing_varargs_named (args_so_far
))
3601 /* Don't include the last named arg. */
3604 /* Treat all args as named. */
3605 n_named_args
= num_actuals
;
3607 /* Make a vector to hold all the information about each arg. */
3608 args
= XCNEWVEC (struct arg_data
, num_actuals
);
3610 /* Build up entries in the ARGS array, compute the size of the
3611 arguments into ARGS_SIZE, etc. */
3612 initialize_argument_information (num_actuals
, args
, &args_size
,
3614 structure_value_addr_value
, fndecl
, fntype
,
3615 args_so_far
, reg_parm_stack_space
,
3616 &old_stack_level
, &old_pending_adj
,
3617 &must_preallocate
, &flags
,
3618 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
3621 must_preallocate
= 1;
3623 /* Now make final decision about preallocating stack space. */
3624 must_preallocate
= finalize_must_preallocate (must_preallocate
,
3628 /* If the structure value address will reference the stack pointer, we
3629 must stabilize it. We don't need to do this if we know that we are
3630 not going to adjust the stack pointer in processing this call. */
3632 if (structure_value_addr
3633 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
3634 || reg_mentioned_p (virtual_outgoing_args_rtx
,
3635 structure_value_addr
))
3637 || (!ACCUMULATE_OUTGOING_ARGS
3638 && maybe_ne (args_size
.constant
, 0))))
3639 structure_value_addr
= copy_to_reg (structure_value_addr
);
3641 /* Tail calls can make things harder to debug, and we've traditionally
3642 pushed these optimizations into -O2. Don't try if we're already
3643 expanding a call, as that means we're an argument. Don't try if
3644 there's cleanups, as we know there's code to follow the call. */
3645 if (currently_expanding_call
++ != 0
3646 || (!flag_optimize_sibling_calls
&& !CALL_FROM_THUNK_P (exp
))
3648 || dbg_cnt (tail_call
) == false)
3651 /* Workaround buggy C/C++ wrappers around Fortran routines with
3652 character(len=constant) arguments if the hidden string length arguments
3653 are passed on the stack; if the callers forget to pass those arguments,
3654 attempting to tail call in such routines leads to stack corruption.
3655 Avoid tail calls in functions where at least one such hidden string
3656 length argument is passed (partially or fully) on the stack in the
3657 caller and the callee needs to pass any arguments on the stack.
3659 if (try_tail_call
&& maybe_ne (args_size
.constant
, 0))
3660 for (tree arg
= DECL_ARGUMENTS (current_function_decl
);
3661 arg
; arg
= DECL_CHAIN (arg
))
3662 if (DECL_HIDDEN_STRING_LENGTH (arg
) && DECL_INCOMING_RTL (arg
))
3664 subrtx_iterator::array_type array
;
3665 FOR_EACH_SUBRTX (iter
, array
, DECL_INCOMING_RTL (arg
), NONCONST
)
3673 /* If the user has marked the function as requiring tail-call
3674 optimization, attempt it. */
3678 /* Rest of purposes for tail call optimizations to fail. */
3680 try_tail_call
= can_implement_as_sibling_call_p (exp
,
3681 structure_value_addr
,
3683 reg_parm_stack_space
,
3685 flags
, addr
, args_size
);
3687 /* Check if caller and callee disagree in promotion of function
3691 machine_mode caller_mode
, caller_promoted_mode
;
3692 machine_mode callee_mode
, callee_promoted_mode
;
3693 int caller_unsignedp
, callee_unsignedp
;
3694 tree caller_res
= DECL_RESULT (current_function_decl
);
3696 caller_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (caller_res
));
3697 caller_mode
= DECL_MODE (caller_res
);
3698 callee_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (funtype
));
3699 callee_mode
= TYPE_MODE (TREE_TYPE (funtype
));
3700 caller_promoted_mode
3701 = promote_function_mode (TREE_TYPE (caller_res
), caller_mode
,
3703 TREE_TYPE (current_function_decl
), 1);
3704 callee_promoted_mode
3705 = promote_function_mode (TREE_TYPE (funtype
), callee_mode
,
3708 if (caller_mode
!= VOIDmode
3709 && (caller_promoted_mode
!= callee_promoted_mode
3710 || ((caller_mode
!= caller_promoted_mode
3711 || callee_mode
!= callee_promoted_mode
)
3712 && (caller_unsignedp
!= callee_unsignedp
3713 || partial_subreg_p (caller_mode
, callee_mode
)))))
3716 maybe_complain_about_tail_call (exp
,
3717 "caller and callee disagree in"
3718 " promotion of function"
3723 /* Ensure current function's preferred stack boundary is at least
3724 what we need. Stack alignment may also increase preferred stack
3726 for (i
= 0; i
< num_actuals
; i
++)
3727 if (reg_parm_stack_space
> 0
3729 || args
[i
].partial
!= 0
3730 || args
[i
].pass_on_stack
)
3731 update_stack_alignment_for_call (&args
[i
].locate
);
3732 if (crtl
->preferred_stack_boundary
< preferred_stack_boundary
)
3733 crtl
->preferred_stack_boundary
= preferred_stack_boundary
;
3735 preferred_stack_boundary
= crtl
->preferred_stack_boundary
;
3737 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
3739 /* We want to make two insn chains; one for a sibling call, the other
3740 for a normal call. We will select one of the two chains after
3741 initial RTL generation is complete. */
3742 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
3744 int sibcall_failure
= 0;
3745 /* We want to emit any pending stack adjustments before the tail
3746 recursion "call". That way we know any adjustment after the tail
3747 recursion call can be ignored if we indeed use the tail
3749 saved_pending_stack_adjust save
;
3750 rtx_insn
*insns
, *before_call
, *after_args
;
3755 /* State variables we need to save and restore between
3757 save_pending_stack_adjust (&save
);
3760 flags
&= ~ECF_SIBCALL
;
3762 flags
|= ECF_SIBCALL
;
3764 /* Other state variables that we must reinitialize each time
3765 through the loop (that are not initialized by the loop itself). */
3769 /* Start a new sequence for the normal call case.
3771 From this point on, if the sibling call fails, we want to set
3772 sibcall_failure instead of continuing the loop. */
3775 /* Don't let pending stack adjusts add up to too much.
3776 Also, do all pending adjustments now if there is any chance
3777 this might be a call to alloca or if we are expanding a sibling
3779 Also do the adjustments before a throwing call, otherwise
3780 exception handling can fail; PR 19225. */
3781 if (maybe_ge (pending_stack_adjust
, 32)
3782 || (maybe_ne (pending_stack_adjust
, 0)
3783 && (flags
& ECF_MAY_BE_ALLOCA
))
3784 || (maybe_ne (pending_stack_adjust
, 0)
3785 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
3787 do_pending_stack_adjust ();
3789 /* Precompute any arguments as needed. */
3791 precompute_arguments (num_actuals
, args
);
3793 /* Now we are about to start emitting insns that can be deleted
3794 if a libcall is deleted. */
3795 if (pass
&& (flags
& ECF_MALLOC
))
3799 && crtl
->stack_protect_guard
3800 && targetm
.stack_protect_runtime_enabled_p ())
3801 stack_protect_epilogue ();
3803 adjusted_args_size
= args_size
;
3804 /* Compute the actual size of the argument block required. The variable
3805 and constant sizes must be combined, the size may have to be rounded,
3806 and there may be a minimum required size. When generating a sibcall
3807 pattern, do not round up, since we'll be re-using whatever space our
3809 unadjusted_args_size
3810 = compute_argument_block_size (reg_parm_stack_space
,
3811 &adjusted_args_size
,
3814 : preferred_stack_boundary
));
3816 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
3818 /* The argument block when performing a sibling call is the
3819 incoming argument block. */
3822 argblock
= crtl
->args
.internal_arg_pointer
;
3823 if (STACK_GROWS_DOWNWARD
)
3825 = plus_constant (Pmode
, argblock
, crtl
->args
.pretend_args_size
);
3828 = plus_constant (Pmode
, argblock
, -crtl
->args
.pretend_args_size
);
3830 HOST_WIDE_INT map_size
= constant_lower_bound (args_size
.constant
);
3831 stored_args_map
= sbitmap_alloc (map_size
);
3832 bitmap_clear (stored_args_map
);
3833 stored_args_watermark
= HOST_WIDE_INT_M1U
;
3836 /* If we have no actual push instructions, or shouldn't use them,
3837 make space for all args right now. */
3838 else if (adjusted_args_size
.var
!= 0)
3840 if (old_stack_level
== 0)
3842 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
3843 old_stack_pointer_delta
= stack_pointer_delta
;
3844 old_pending_adj
= pending_stack_adjust
;
3845 pending_stack_adjust
= 0;
3846 /* stack_arg_under_construction says whether a stack arg is
3847 being constructed at the old stack level. Pushing the stack
3848 gets a clean outgoing argument block. */
3849 old_stack_arg_under_construction
= stack_arg_under_construction
;
3850 stack_arg_under_construction
= 0;
3852 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
3853 if (flag_stack_usage_info
)
3854 current_function_has_unbounded_dynamic_stack_size
= 1;
3858 /* Note that we must go through the motions of allocating an argument
3859 block even if the size is zero because we may be storing args
3860 in the area reserved for register arguments, which may be part of
3863 poly_int64 needed
= adjusted_args_size
.constant
;
3865 /* Store the maximum argument space used. It will be pushed by
3866 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
3869 crtl
->outgoing_args_size
= upper_bound (crtl
->outgoing_args_size
,
3872 if (must_preallocate
)
3874 if (ACCUMULATE_OUTGOING_ARGS
)
3876 /* Since the stack pointer will never be pushed, it is
3877 possible for the evaluation of a parm to clobber
3878 something we have already written to the stack.
3879 Since most function calls on RISC machines do not use
3880 the stack, this is uncommon, but must work correctly.
3882 Therefore, we save any area of the stack that was already
3883 written and that we are using. Here we set up to do this
3884 by making a new stack usage map from the old one. The
3885 actual save will be done by store_one_arg.
3887 Another approach might be to try to reorder the argument
3888 evaluations to avoid this conflicting stack usage. */
3890 /* Since we will be writing into the entire argument area,
3891 the map must be allocated for its entire size, not just
3892 the part that is the responsibility of the caller. */
3893 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3894 needed
+= reg_parm_stack_space
;
3896 poly_int64 limit
= needed
;
3897 if (ARGS_GROW_DOWNWARD
)
3900 /* For polynomial sizes, this is the maximum possible
3901 size needed for arguments with a constant size
3903 HOST_WIDE_INT const_limit
= constant_lower_bound (limit
);
3904 highest_outgoing_arg_in_use
3905 = MAX (initial_highest_arg_in_use
, const_limit
);
3907 free (stack_usage_map_buf
);
3908 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
3909 stack_usage_map
= stack_usage_map_buf
;
3911 if (initial_highest_arg_in_use
)
3912 memcpy (stack_usage_map
, initial_stack_usage_map
,
3913 initial_highest_arg_in_use
);
3915 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3916 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3917 (highest_outgoing_arg_in_use
3918 - initial_highest_arg_in_use
));
3921 /* The address of the outgoing argument list must not be
3922 copied to a register here, because argblock would be left
3923 pointing to the wrong place after the call to
3924 allocate_dynamic_stack_space below. */
3926 argblock
= virtual_outgoing_args_rtx
;
3930 /* Try to reuse some or all of the pending_stack_adjust
3931 to get this space. */
3932 if (inhibit_defer_pop
== 0
3933 && (combine_pending_stack_adjustment_and_call
3935 unadjusted_args_size
,
3936 &adjusted_args_size
,
3937 preferred_unit_stack_boundary
)))
3939 /* combine_pending_stack_adjustment_and_call computes
3940 an adjustment before the arguments are allocated.
3941 Account for them and see whether or not the stack
3942 needs to go up or down. */
3943 needed
= unadjusted_args_size
- needed
;
3946 combine_pending_stack_adjustment_and_call. */
3947 gcc_checking_assert (ordered_p (needed
, 0));
3948 if (maybe_lt (needed
, 0))
3950 /* We're releasing stack space. */
3951 /* ??? We can avoid any adjustment at all if we're
3952 already aligned. FIXME. */
3953 pending_stack_adjust
= -needed
;
3954 do_pending_stack_adjust ();
3958 /* We need to allocate space. We'll do that in
3959 push_block below. */
3960 pending_stack_adjust
= 0;
3963 /* Special case this because overhead of `push_block' in
3964 this case is non-trivial. */
3965 if (known_eq (needed
, 0))
3966 argblock
= virtual_outgoing_args_rtx
;
3969 rtx needed_rtx
= gen_int_mode (needed
, Pmode
);
3970 argblock
= push_block (needed_rtx
, 0, 0);
3971 if (ARGS_GROW_DOWNWARD
)
3972 argblock
= plus_constant (Pmode
, argblock
, needed
);
3975 /* We only really need to call `copy_to_reg' in the case
3976 where push insns are going to be used to pass ARGBLOCK
3977 to a function call in ARGS. In that case, the stack
3978 pointer changes value from the allocation point to the
3979 call point, and hence the value of
3980 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3981 as well always do it. */
3982 argblock
= copy_to_reg (argblock
);
3987 if (ACCUMULATE_OUTGOING_ARGS
)
3989 /* The save/restore code in store_one_arg handles all
3990 cases except one: a constructor call (including a C
3991 function returning a BLKmode struct) to initialize
3993 if (stack_arg_under_construction
)
3997 (adjusted_args_size
.constant
3998 + (OUTGOING_REG_PARM_STACK_SPACE (!fndecl
? fntype
3999 : TREE_TYPE (fndecl
))
4000 ? 0 : reg_parm_stack_space
), Pmode
));
4001 if (old_stack_level
== 0)
4003 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
4004 old_stack_pointer_delta
= stack_pointer_delta
;
4005 old_pending_adj
= pending_stack_adjust
;
4006 pending_stack_adjust
= 0;
4007 /* stack_arg_under_construction says whether a stack
4008 arg is being constructed at the old stack level.
4009 Pushing the stack gets a clean outgoing argument
4011 old_stack_arg_under_construction
4012 = stack_arg_under_construction
;
4013 stack_arg_under_construction
= 0;
4014 /* Make a new map for the new argument list. */
4015 free (stack_usage_map_buf
);
4016 stack_usage_map_buf
= XCNEWVEC (char, highest_outgoing_arg_in_use
);
4017 stack_usage_map
= stack_usage_map_buf
;
4018 highest_outgoing_arg_in_use
= 0;
4019 stack_usage_watermark
= HOST_WIDE_INT_M1U
;
4021 /* We can pass TRUE as the 4th argument because we just
4022 saved the stack pointer and will restore it right after
4024 allocate_dynamic_stack_space (push_size
, 0, BIGGEST_ALIGNMENT
,
4028 /* If argument evaluation might modify the stack pointer,
4029 copy the address of the argument list to a register. */
4030 for (i
= 0; i
< num_actuals
; i
++)
4031 if (args
[i
].pass_on_stack
)
4033 argblock
= copy_addr_to_reg (argblock
);
4038 compute_argument_addresses (args
, argblock
, num_actuals
);
4040 /* Stack is properly aligned, pops can't safely be deferred during
4041 the evaluation of the arguments. */
4044 /* Precompute all register parameters. It isn't safe to compute
4045 anything once we have started filling any specific hard regs.
4046 TLS symbols sometimes need a call to resolve. Precompute
4047 register parameters before any stack pointer manipulation
4048 to avoid unaligned stack in the called function. */
4049 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
4053 /* Perform stack alignment before the first push (the last arg). */
4055 && maybe_gt (adjusted_args_size
.constant
, reg_parm_stack_space
)
4056 && maybe_ne (adjusted_args_size
.constant
, unadjusted_args_size
))
4058 /* When the stack adjustment is pending, we get better code
4059 by combining the adjustments. */
4060 if (maybe_ne (pending_stack_adjust
, 0)
4061 && ! inhibit_defer_pop
4062 && (combine_pending_stack_adjustment_and_call
4063 (&pending_stack_adjust
,
4064 unadjusted_args_size
,
4065 &adjusted_args_size
,
4066 preferred_unit_stack_boundary
)))
4067 do_pending_stack_adjust ();
4068 else if (argblock
== 0)
4069 anti_adjust_stack (gen_int_mode (adjusted_args_size
.constant
4070 - unadjusted_args_size
,
4073 /* Now that the stack is properly aligned, pops can't safely
4074 be deferred during the evaluation of the arguments. */
4077 /* Record the maximum pushed stack space size. We need to delay
4078 doing it this far to take into account the optimization done
4079 by combine_pending_stack_adjustment_and_call. */
4080 if (flag_stack_usage_info
4081 && !ACCUMULATE_OUTGOING_ARGS
4083 && adjusted_args_size
.var
== 0)
4085 poly_int64 pushed
= (adjusted_args_size
.constant
4086 + pending_stack_adjust
);
4087 current_function_pushed_stack_size
4088 = upper_bound (current_function_pushed_stack_size
, pushed
);
4091 funexp
= rtx_for_function_call (fndecl
, addr
);
4093 if (CALL_EXPR_STATIC_CHAIN (exp
))
4094 static_chain_value
= expand_normal (CALL_EXPR_STATIC_CHAIN (exp
));
4096 static_chain_value
= 0;
4098 #ifdef REG_PARM_STACK_SPACE
4099 /* Save the fixed argument area if it's part of the caller's frame and
4100 is clobbered by argument setup for this call. */
4101 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
4102 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
4103 &low_to_save
, &high_to_save
);
4106 /* Now store (and compute if necessary) all non-register parms.
4107 These come before register parms, since they can require block-moves,
4108 which could clobber the registers used for register parms.
4109 Parms which have partial registers are not stored here,
4110 but we do preallocate space here if they want that. */
4112 for (i
= 0; i
< num_actuals
; i
++)
4114 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
4116 rtx_insn
*before_arg
= get_last_insn ();
4118 /* We don't allow passing huge (> 2^30 B) arguments
4119 by value. It would cause an overflow later on. */
4120 if (constant_lower_bound (adjusted_args_size
.constant
)
4121 >= (1 << (HOST_BITS_PER_INT
- 2)))
4123 sorry ("passing too large argument on stack");
4127 if (store_one_arg (&args
[i
], argblock
, flags
,
4128 adjusted_args_size
.var
!= 0,
4129 reg_parm_stack_space
)
4131 && check_sibcall_argument_overlap (before_arg
,
4133 sibcall_failure
= 1;
4138 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
4139 gen_rtx_USE (VOIDmode
, args
[i
].stack
),
4143 /* If we have a parm that is passed in registers but not in memory
4144 and whose alignment does not permit a direct copy into registers,
4145 make a group of pseudos that correspond to each register that we
4147 if (STRICT_ALIGNMENT
)
4148 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
4150 /* Now store any partially-in-registers parm.
4151 This is the last place a block-move can happen. */
4153 for (i
= 0; i
< num_actuals
; i
++)
4154 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
4156 rtx_insn
*before_arg
= get_last_insn ();
4158 /* On targets with weird calling conventions (e.g. PA) it's
4159 hard to ensure that all cases of argument overlap between
4160 stack and registers work. Play it safe and bail out. */
4161 if (ARGS_GROW_DOWNWARD
&& !STACK_GROWS_DOWNWARD
)
4163 sibcall_failure
= 1;
4167 if (store_one_arg (&args
[i
], argblock
, flags
,
4168 adjusted_args_size
.var
!= 0,
4169 reg_parm_stack_space
)
4171 && check_sibcall_argument_overlap (before_arg
,
4173 sibcall_failure
= 1;
4176 bool any_regs
= false;
4177 for (i
= 0; i
< num_actuals
; i
++)
4178 if (args
[i
].reg
!= NULL_RTX
)
4181 targetm
.calls
.call_args (args
[i
].reg
, funtype
);
4184 targetm
.calls
.call_args (pc_rtx
, funtype
);
4186 /* Figure out the register where the value, if any, will come back. */
4188 if (TYPE_MODE (rettype
) != VOIDmode
4189 && ! structure_value_addr
)
4191 if (pcc_struct_value
)
4192 valreg
= hard_function_value (build_pointer_type (rettype
),
4193 fndecl
, NULL
, (pass
== 0));
4195 valreg
= hard_function_value (rettype
, fndecl
, fntype
,
4198 /* If VALREG is a PARALLEL whose first member has a zero
4199 offset, use that. This is for targets such as m68k that
4200 return the same value in multiple places. */
4201 if (GET_CODE (valreg
) == PARALLEL
)
4203 rtx elem
= XVECEXP (valreg
, 0, 0);
4204 rtx where
= XEXP (elem
, 0);
4205 rtx offset
= XEXP (elem
, 1);
4206 if (offset
== const0_rtx
4207 && GET_MODE (where
) == GET_MODE (valreg
))
4212 /* If register arguments require space on the stack and stack space
4213 was not preallocated, allocate stack space here for arguments
4214 passed in registers. */
4215 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
4216 && !ACCUMULATE_OUTGOING_ARGS
4217 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
4218 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
4220 /* Pass the function the address in which to return a
4222 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
4224 structure_value_addr
4225 = convert_memory_address (Pmode
, structure_value_addr
);
4226 emit_move_insn (struct_value
,
4228 force_operand (structure_value_addr
,
4231 if (REG_P (struct_value
))
4232 use_reg (&call_fusage
, struct_value
);
4235 after_args
= get_last_insn ();
4236 funexp
= prepare_call_address (fndecl
? fndecl
: fntype
, funexp
,
4237 static_chain_value
, &call_fusage
,
4238 reg_parm_seen
, flags
);
4240 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
4241 pass
== 0, &sibcall_failure
);
4243 /* Save a pointer to the last insn before the call, so that we can
4244 later safely search backwards to find the CALL_INSN. */
4245 before_call
= get_last_insn ();
4247 /* Set up next argument register. For sibling calls on machines
4248 with register windows this should be the incoming register. */
4250 next_arg_reg
= targetm
.calls
.function_incoming_arg (args_so_far
,
4255 next_arg_reg
= targetm
.calls
.function_arg (args_so_far
,
4256 VOIDmode
, void_type_node
,
4259 if (pass
== 1 && (return_flags
& ERF_RETURNS_ARG
))
4261 int arg_nr
= return_flags
& ERF_RETURN_ARG_MASK
;
4262 arg_nr
= num_actuals
- arg_nr
- 1;
4264 && arg_nr
< num_actuals
4268 && GET_MODE (args
[arg_nr
].reg
) == GET_MODE (valreg
))
4270 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args
[arg_nr
].tree_value
)),
4271 gen_rtx_SET (valreg
, args
[arg_nr
].reg
),
4274 /* All arguments and registers used for the call must be set up by
4277 /* Stack must be properly aligned now. */
4279 || multiple_p (stack_pointer_delta
,
4280 preferred_unit_stack_boundary
));
4282 /* Generate the actual call instruction. */
4283 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
4284 adjusted_args_size
.constant
, struct_value_size
,
4285 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
4286 flags
, args_so_far
);
4290 rtx_call_insn
*last
;
4291 rtx datum
= NULL_RTX
;
4292 if (fndecl
!= NULL_TREE
)
4294 datum
= XEXP (DECL_RTL (fndecl
), 0);
4295 gcc_assert (datum
!= NULL_RTX
4296 && GET_CODE (datum
) == SYMBOL_REF
);
4298 last
= last_call_insn ();
4299 add_reg_note (last
, REG_CALL_DECL
, datum
);
4302 /* If the call setup or the call itself overlaps with anything
4303 of the argument setup we probably clobbered our call address.
4304 In that case we can't do sibcalls. */
4306 && check_sibcall_argument_overlap (after_args
, 0, 0))
4307 sibcall_failure
= 1;
4309 /* If a non-BLKmode value is returned at the most significant end
4310 of a register, shift the register right by the appropriate amount
4311 and update VALREG accordingly. BLKmode values are handled by the
4312 group load/store machinery below. */
4313 if (!structure_value_addr
4314 && !pcc_struct_value
4315 && TYPE_MODE (rettype
) != VOIDmode
4316 && TYPE_MODE (rettype
) != BLKmode
4318 && targetm
.calls
.return_in_msb (rettype
))
4320 if (shift_return_value (TYPE_MODE (rettype
), false, valreg
))
4321 sibcall_failure
= 1;
4322 valreg
= gen_rtx_REG (TYPE_MODE (rettype
), REGNO (valreg
));
4325 if (pass
&& (flags
& ECF_MALLOC
))
4327 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
4328 rtx_insn
*last
, *insns
;
4330 /* The return value from a malloc-like function is a pointer. */
4331 if (TREE_CODE (rettype
) == POINTER_TYPE
)
4332 mark_reg_pointer (temp
, MALLOC_ABI_ALIGNMENT
);
4334 emit_move_insn (temp
, valreg
);
4336 /* The return value from a malloc-like function cannot alias
4338 last
= get_last_insn ();
4339 add_reg_note (last
, REG_NOALIAS
, temp
);
4341 /* Write out the sequence. */
4342 insns
= get_insns ();
4348 /* For calls to `setjmp', etc., inform
4349 function.c:setjmp_warnings that it should complain if
4350 nonvolatile values are live. For functions that cannot
4351 return, inform flow that control does not fall through. */
4353 if ((flags
& ECF_NORETURN
) || pass
== 0)
4355 /* The barrier must be emitted
4356 immediately after the CALL_INSN. Some ports emit more
4357 than just a CALL_INSN above, so we must search for it here. */
4359 rtx_insn
*last
= get_last_insn ();
4360 while (!CALL_P (last
))
4362 last
= PREV_INSN (last
);
4363 /* There was no CALL_INSN? */
4364 gcc_assert (last
!= before_call
);
4367 emit_barrier_after (last
);
4369 /* Stack adjustments after a noreturn call are dead code.
4370 However when NO_DEFER_POP is in effect, we must preserve
4371 stack_pointer_delta. */
4372 if (inhibit_defer_pop
== 0)
4374 stack_pointer_delta
= old_stack_allocated
;
4375 pending_stack_adjust
= 0;
4379 /* If value type not void, return an rtx for the value. */
4381 if (TYPE_MODE (rettype
) == VOIDmode
4383 target
= const0_rtx
;
4384 else if (structure_value_addr
)
4386 if (target
== 0 || !MEM_P (target
))
4389 = gen_rtx_MEM (TYPE_MODE (rettype
),
4390 memory_address (TYPE_MODE (rettype
),
4391 structure_value_addr
));
4392 set_mem_attributes (target
, rettype
, 1);
4395 else if (pcc_struct_value
)
4397 /* This is the special C++ case where we need to
4398 know what the true target was. We take care to
4399 never use this value more than once in one expression. */
4400 target
= gen_rtx_MEM (TYPE_MODE (rettype
),
4401 copy_to_reg (valreg
));
4402 set_mem_attributes (target
, rettype
, 1);
4404 /* Handle calls that return values in multiple non-contiguous locations.
4405 The Irix 6 ABI has examples of this. */
4406 else if (GET_CODE (valreg
) == PARALLEL
)
4409 target
= emit_group_move_into_temps (valreg
);
4410 else if (rtx_equal_p (target
, valreg
))
4412 else if (GET_CODE (target
) == PARALLEL
)
4413 /* Handle the result of a emit_group_move_into_temps
4414 call in the previous pass. */
4415 emit_group_move (target
, valreg
);
4417 emit_group_store (target
, valreg
, rettype
,
4418 int_size_in_bytes (rettype
));
4421 && GET_MODE (target
) == TYPE_MODE (rettype
)
4422 && GET_MODE (target
) == GET_MODE (valreg
))
4424 bool may_overlap
= false;
4426 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
4427 reg to a plain register. */
4428 if (!REG_P (target
) || HARD_REGISTER_P (target
))
4429 valreg
= avoid_likely_spilled_reg (valreg
);
4431 /* If TARGET is a MEM in the argument area, and we have
4432 saved part of the argument area, then we can't store
4433 directly into TARGET as it may get overwritten when we
4434 restore the argument save area below. Don't work too
4435 hard though and simply force TARGET to a register if it
4436 is a MEM; the optimizer is quite likely to sort it out. */
4437 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
4438 for (i
= 0; i
< num_actuals
; i
++)
4439 if (args
[i
].save_area
)
4446 target
= copy_to_reg (valreg
);
4449 /* TARGET and VALREG cannot be equal at this point
4450 because the latter would not have
4451 REG_FUNCTION_VALUE_P true, while the former would if
4452 it were referring to the same register.
4454 If they refer to the same register, this move will be
4455 a no-op, except when function inlining is being
4457 emit_move_insn (target
, valreg
);
4459 /* If we are setting a MEM, this code must be executed.
4460 Since it is emitted after the call insn, sibcall
4461 optimization cannot be performed in that case. */
4463 sibcall_failure
= 1;
4467 target
= copy_to_reg (avoid_likely_spilled_reg (valreg
));
4469 /* If we promoted this return value, make the proper SUBREG.
4470 TARGET might be const0_rtx here, so be careful. */
4472 && TYPE_MODE (rettype
) != BLKmode
4473 && GET_MODE (target
) != TYPE_MODE (rettype
))
4475 tree type
= rettype
;
4476 int unsignedp
= TYPE_UNSIGNED (type
);
4479 /* Ensure we promote as expected, and get the new unsignedness. */
4480 pmode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
4482 gcc_assert (GET_MODE (target
) == pmode
);
4484 poly_uint64 offset
= subreg_lowpart_offset (TYPE_MODE (type
),
4486 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
4487 SUBREG_PROMOTED_VAR_P (target
) = 1;
4488 SUBREG_PROMOTED_SET (target
, unsignedp
);
4491 /* If size of args is variable or this was a constructor call for a stack
4492 argument, restore saved stack-pointer value. */
4494 if (old_stack_level
)
4496 rtx_insn
*prev
= get_last_insn ();
4498 emit_stack_restore (SAVE_BLOCK
, old_stack_level
);
4499 stack_pointer_delta
= old_stack_pointer_delta
;
4501 fixup_args_size_notes (prev
, get_last_insn (), stack_pointer_delta
);
4503 pending_stack_adjust
= old_pending_adj
;
4504 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
4505 stack_arg_under_construction
= old_stack_arg_under_construction
;
4506 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4507 stack_usage_map
= initial_stack_usage_map
;
4508 stack_usage_watermark
= initial_stack_usage_watermark
;
4509 sibcall_failure
= 1;
4511 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
4513 #ifdef REG_PARM_STACK_SPACE
4515 restore_fixed_argument_area (save_area
, argblock
,
4516 high_to_save
, low_to_save
);
4519 /* If we saved any argument areas, restore them. */
4520 for (i
= 0; i
< num_actuals
; i
++)
4521 if (args
[i
].save_area
)
4523 machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
4525 = gen_rtx_MEM (save_mode
,
4526 memory_address (save_mode
,
4527 XEXP (args
[i
].stack_slot
, 0)));
4529 if (save_mode
!= BLKmode
)
4530 emit_move_insn (stack_area
, args
[i
].save_area
);
4532 emit_block_move (stack_area
, args
[i
].save_area
,
4534 (args
[i
].locate
.size
.constant
, Pmode
)),
4535 BLOCK_OP_CALL_PARM
);
4538 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4539 stack_usage_map
= initial_stack_usage_map
;
4540 stack_usage_watermark
= initial_stack_usage_watermark
;
4543 /* If this was alloca, record the new stack level. */
4544 if (flags
& ECF_MAY_BE_ALLOCA
)
4545 record_new_stack_level ();
4547 /* Free up storage we no longer need. */
4548 for (i
= 0; i
< num_actuals
; ++i
)
4549 free (args
[i
].aligned_regs
);
4551 targetm
.calls
.end_call_args ();
4553 insns
= get_insns ();
4558 tail_call_insns
= insns
;
4560 /* Restore the pending stack adjustment now that we have
4561 finished generating the sibling call sequence. */
4563 restore_pending_stack_adjust (&save
);
4565 /* Prepare arg structure for next iteration. */
4566 for (i
= 0; i
< num_actuals
; i
++)
4569 args
[i
].aligned_regs
= 0;
4573 sbitmap_free (stored_args_map
);
4574 internal_arg_pointer_exp_state
.scan_start
= NULL
;
4575 internal_arg_pointer_exp_state
.cache
.release ();
4579 normal_call_insns
= insns
;
4581 /* Verify that we've deallocated all the stack we used. */
4582 gcc_assert ((flags
& ECF_NORETURN
)
4583 || known_eq (old_stack_allocated
,
4585 - pending_stack_adjust
));
4588 /* If something prevents making this a sibling call,
4589 zero out the sequence. */
4590 if (sibcall_failure
)
4591 tail_call_insns
= NULL
;
4596 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
4597 arguments too, as argument area is now clobbered by the call. */
4598 if (tail_call_insns
)
4600 emit_insn (tail_call_insns
);
4601 crtl
->tail_call_emit
= true;
4605 emit_insn (normal_call_insns
);
4607 /* Ideally we'd emit a message for all of the ways that it could
4609 maybe_complain_about_tail_call (exp
, "tail call production failed");
4612 currently_expanding_call
--;
4614 free (stack_usage_map_buf
);
4619 /* A sibling call sequence invalidates any REG_EQUIV notes made for
4620 this function's incoming arguments.
4622 At the start of RTL generation we know the only REG_EQUIV notes
4623 in the rtl chain are those for incoming arguments, so we can look
4624 for REG_EQUIV notes between the start of the function and the
4625 NOTE_INSN_FUNCTION_BEG.
4627 This is (slight) overkill. We could keep track of the highest
4628 argument we clobber and be more selective in removing notes, but it
4629 does not seem to be worth the effort. */
4632 fixup_tail_calls (void)
4636 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4640 /* There are never REG_EQUIV notes for the incoming arguments
4641 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
4643 && NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
)
4646 note
= find_reg_note (insn
, REG_EQUIV
, 0);
4648 remove_note (insn
, note
);
4649 note
= find_reg_note (insn
, REG_EQUIV
, 0);
4654 /* Traverse a list of TYPES and expand all complex types into their
4657 split_complex_types (tree types
)
4661 /* Before allocating memory, check for the common case of no complex. */
4662 for (p
= types
; p
; p
= TREE_CHAIN (p
))
4664 tree type
= TREE_VALUE (p
);
4665 if (TREE_CODE (type
) == COMPLEX_TYPE
4666 && targetm
.calls
.split_complex_arg (type
))
4672 types
= copy_list (types
);
4674 for (p
= types
; p
; p
= TREE_CHAIN (p
))
4676 tree complex_type
= TREE_VALUE (p
);
4678 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
4679 && targetm
.calls
.split_complex_arg (complex_type
))
4683 /* Rewrite complex type with component type. */
4684 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
4685 next
= TREE_CHAIN (p
);
4687 /* Add another component type for the imaginary part. */
4688 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
4689 TREE_CHAIN (p
) = imag
;
4690 TREE_CHAIN (imag
) = next
;
4692 /* Skip the newly created node. */
4700 /* Output a library call to function ORGFUN (a SYMBOL_REF rtx)
4701 for a value of mode OUTMODE,
4702 with NARGS different arguments, passed as ARGS.
4703 Store the return value if RETVAL is nonzero: store it in VALUE if
4704 VALUE is nonnull, otherwise pick a convenient location. In either
4705 case return the location of the stored value.
4707 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4708 `const' calls, LCT_PURE for `pure' calls, or another LCT_ value for
4709 other types of library calls. */
4712 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
4713 enum libcall_type fn_type
,
4714 machine_mode outmode
, int nargs
, rtx_mode_t
*args
)
4716 /* Total size in bytes of all the stack-parms scanned so far. */
4717 struct args_size args_size
;
4718 /* Size of arguments before any adjustments (such as rounding). */
4719 struct args_size original_args_size
;
4722 /* Todo, choose the correct decl type of orgfun. Sadly this information
4723 isn't present here, so we default to native calling abi here. */
4724 tree fndecl ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
4725 tree fntype ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
4728 CUMULATIVE_ARGS args_so_far_v
;
4729 cumulative_args_t args_so_far
;
4736 struct locate_and_pad_arg_data locate
;
4740 int old_inhibit_defer_pop
= inhibit_defer_pop
;
4741 rtx call_fusage
= 0;
4744 int pcc_struct_value
= 0;
4745 poly_int64 struct_value_size
= 0;
4747 int reg_parm_stack_space
= 0;
4749 rtx_insn
*before_call
;
4750 bool have_push_fusage
;
4751 tree tfom
; /* type_for_mode (outmode, 0) */
4753 #ifdef REG_PARM_STACK_SPACE
4754 /* Define the boundary of the register parm stack space that needs to be
4756 int low_to_save
= 0, high_to_save
= 0;
4757 rtx save_area
= 0; /* Place that it is saved. */
4760 /* Size of the stack reserved for parameter registers. */
4761 unsigned int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
4762 char *initial_stack_usage_map
= stack_usage_map
;
4763 unsigned HOST_WIDE_INT initial_stack_usage_watermark
= stack_usage_watermark
;
4764 char *stack_usage_map_buf
= NULL
;
4766 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
4768 #ifdef REG_PARM_STACK_SPACE
4769 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
4772 /* By default, library functions cannot throw. */
4773 flags
= ECF_NOTHROW
;
4786 flags
|= ECF_NORETURN
;
4789 flags
&= ~ECF_NOTHROW
;
4791 case LCT_RETURNS_TWICE
:
4792 flags
= ECF_RETURNS_TWICE
;
4797 /* Ensure current function's preferred stack boundary is at least
4799 if (crtl
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
4800 crtl
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
4802 /* If this kind of value comes back in memory,
4803 decide where in memory it should come back. */
4804 if (outmode
!= VOIDmode
)
4806 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
4807 if (aggregate_value_p (tfom
, 0))
4809 #ifdef PCC_STATIC_STRUCT_RETURN
4811 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
4812 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
4813 pcc_struct_value
= 1;
4815 value
= gen_reg_rtx (outmode
);
4816 #else /* not PCC_STATIC_STRUCT_RETURN */
4817 struct_value_size
= GET_MODE_SIZE (outmode
);
4818 if (value
!= 0 && MEM_P (value
))
4821 mem_value
= assign_temp (tfom
, 1, 1);
4823 /* This call returns a big structure. */
4824 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
4828 tfom
= void_type_node
;
4830 /* ??? Unfinished: must pass the memory address as an argument. */
4832 /* Copy all the libcall-arguments out of the varargs data
4833 and into a vector ARGVEC.
4835 Compute how to pass each argument. We only support a very small subset
4836 of the full argument passing conventions to limit complexity here since
4837 library functions shouldn't have many args. */
4839 argvec
= XALLOCAVEC (struct arg
, nargs
+ 1);
4840 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
4842 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
4843 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v
, outmode
, fun
);
4845 INIT_CUMULATIVE_ARGS (args_so_far_v
, NULL_TREE
, fun
, 0, nargs
);
4847 args_so_far
= pack_cumulative_args (&args_so_far_v
);
4849 args_size
.constant
= 0;
4856 /* If there's a structure value address to be passed,
4857 either pass it in the special place, or pass it as an extra argument. */
4858 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
4860 rtx addr
= XEXP (mem_value
, 0);
4864 /* Make sure it is a reasonable operand for a move or push insn. */
4865 if (!REG_P (addr
) && !MEM_P (addr
)
4866 && !(CONSTANT_P (addr
)
4867 && targetm
.legitimate_constant_p (Pmode
, addr
)))
4868 addr
= force_operand (addr
, NULL_RTX
);
4870 argvec
[count
].value
= addr
;
4871 argvec
[count
].mode
= Pmode
;
4872 argvec
[count
].partial
= 0;
4874 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
,
4875 Pmode
, NULL_TREE
, true);
4876 gcc_assert (targetm
.calls
.arg_partial_bytes (args_so_far
, Pmode
,
4877 NULL_TREE
, 1) == 0);
4879 locate_and_pad_parm (Pmode
, NULL_TREE
,
4880 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4883 argvec
[count
].reg
!= 0,
4885 reg_parm_stack_space
, 0,
4886 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
4888 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
4889 || reg_parm_stack_space
> 0)
4890 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
4892 targetm
.calls
.function_arg_advance (args_so_far
, Pmode
, (tree
) 0, true);
4897 for (unsigned int i
= 0; count
< nargs
; i
++, count
++)
4899 rtx val
= args
[i
].first
;
4900 machine_mode mode
= args
[i
].second
;
4903 /* We cannot convert the arg value to the mode the library wants here;
4904 must do it earlier where we know the signedness of the arg. */
4905 gcc_assert (mode
!= BLKmode
4906 && (GET_MODE (val
) == mode
|| GET_MODE (val
) == VOIDmode
));
4908 /* Make sure it is a reasonable operand for a move or push insn. */
4909 if (!REG_P (val
) && !MEM_P (val
)
4910 && !(CONSTANT_P (val
) && targetm
.legitimate_constant_p (mode
, val
)))
4911 val
= force_operand (val
, NULL_RTX
);
4913 if (pass_by_reference (&args_so_far_v
, mode
, NULL_TREE
, 1))
4917 = !reference_callee_copied (&args_so_far_v
, mode
, NULL_TREE
, 1);
4919 /* If this was a CONST function, it is now PURE since it now
4921 if (flags
& ECF_CONST
)
4923 flags
&= ~ECF_CONST
;
4927 if (MEM_P (val
) && !must_copy
)
4929 tree val_expr
= MEM_EXPR (val
);
4931 mark_addressable (val_expr
);
4936 slot
= assign_temp (lang_hooks
.types
.type_for_mode (mode
, 0),
4938 emit_move_insn (slot
, val
);
4941 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
4942 gen_rtx_USE (VOIDmode
, slot
),
4945 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
4946 gen_rtx_CLOBBER (VOIDmode
,
4951 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
4954 mode
= promote_function_mode (NULL_TREE
, mode
, &unsigned_p
, NULL_TREE
, 0);
4955 argvec
[count
].mode
= mode
;
4956 argvec
[count
].value
= convert_modes (mode
, GET_MODE (val
), val
, unsigned_p
);
4957 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
, mode
,
4960 argvec
[count
].partial
4961 = targetm
.calls
.arg_partial_bytes (args_so_far
, mode
, NULL_TREE
, 1);
4963 if (argvec
[count
].reg
== 0
4964 || argvec
[count
].partial
!= 0
4965 || reg_parm_stack_space
> 0)
4967 locate_and_pad_parm (mode
, NULL_TREE
,
4968 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4971 argvec
[count
].reg
!= 0,
4973 reg_parm_stack_space
, argvec
[count
].partial
,
4974 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
4975 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
4976 gcc_assert (!argvec
[count
].locate
.size
.var
);
4978 #ifdef BLOCK_REG_PADDING
4980 /* The argument is passed entirely in registers. See at which
4981 end it should be padded. */
4982 argvec
[count
].locate
.where_pad
=
4983 BLOCK_REG_PADDING (mode
, NULL_TREE
,
4984 known_le (GET_MODE_SIZE (mode
), UNITS_PER_WORD
));
4987 targetm
.calls
.function_arg_advance (args_so_far
, mode
, (tree
) 0, true);
4990 for (int i
= 0; i
< nargs
; i
++)
4991 if (reg_parm_stack_space
> 0
4992 || argvec
[i
].reg
== 0
4993 || argvec
[i
].partial
!= 0)
4994 update_stack_alignment_for_call (&argvec
[i
].locate
);
4996 /* If this machine requires an external definition for library
4997 functions, write one out. */
4998 assemble_external_libcall (fun
);
5000 original_args_size
= args_size
;
5001 args_size
.constant
= (aligned_upper_bound (args_size
.constant
5002 + stack_pointer_delta
,
5004 - stack_pointer_delta
);
5006 args_size
.constant
= upper_bound (args_size
.constant
,
5007 reg_parm_stack_space
);
5009 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
5010 args_size
.constant
-= reg_parm_stack_space
;
5012 crtl
->outgoing_args_size
= upper_bound (crtl
->outgoing_args_size
,
5013 args_size
.constant
);
5015 if (flag_stack_usage_info
&& !ACCUMULATE_OUTGOING_ARGS
)
5017 poly_int64 pushed
= args_size
.constant
+ pending_stack_adjust
;
5018 current_function_pushed_stack_size
5019 = upper_bound (current_function_pushed_stack_size
, pushed
);
5022 if (ACCUMULATE_OUTGOING_ARGS
)
5024 /* Since the stack pointer will never be pushed, it is possible for
5025 the evaluation of a parm to clobber something we have already
5026 written to the stack. Since most function calls on RISC machines
5027 do not use the stack, this is uncommon, but must work correctly.
5029 Therefore, we save any area of the stack that was already written
5030 and that we are using. Here we set up to do this by making a new
5031 stack usage map from the old one.
5033 Another approach might be to try to reorder the argument
5034 evaluations to avoid this conflicting stack usage. */
5036 needed
= args_size
.constant
;
5038 /* Since we will be writing into the entire argument area, the
5039 map must be allocated for its entire size, not just the part that
5040 is the responsibility of the caller. */
5041 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
5042 needed
+= reg_parm_stack_space
;
5044 poly_int64 limit
= needed
;
5045 if (ARGS_GROW_DOWNWARD
)
5048 /* For polynomial sizes, this is the maximum possible size needed
5049 for arguments with a constant size and offset. */
5050 HOST_WIDE_INT const_limit
= constant_lower_bound (limit
);
5051 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
5054 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
5055 stack_usage_map
= stack_usage_map_buf
;
5057 if (initial_highest_arg_in_use
)
5058 memcpy (stack_usage_map
, initial_stack_usage_map
,
5059 initial_highest_arg_in_use
);
5061 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
5062 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
5063 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
5066 /* We must be careful to use virtual regs before they're instantiated,
5067 and real regs afterwards. Loop optimization, for example, can create
5068 new libcalls after we've instantiated the virtual regs, and if we
5069 use virtuals anyway, they won't match the rtl patterns. */
5071 if (virtuals_instantiated
)
5072 argblock
= plus_constant (Pmode
, stack_pointer_rtx
,
5073 STACK_POINTER_OFFSET
);
5075 argblock
= virtual_outgoing_args_rtx
;
5080 argblock
= push_block (gen_int_mode (args_size
.constant
, Pmode
), 0, 0);
5083 /* We push args individually in reverse order, perform stack alignment
5084 before the first push (the last arg). */
5086 anti_adjust_stack (gen_int_mode (args_size
.constant
5087 - original_args_size
.constant
,
5092 #ifdef REG_PARM_STACK_SPACE
5093 if (ACCUMULATE_OUTGOING_ARGS
)
5095 /* The argument list is the property of the called routine and it
5096 may clobber it. If the fixed area has been used for previous
5097 parameters, we must save and restore it. */
5098 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
5099 &low_to_save
, &high_to_save
);
5103 /* When expanding a normal call, args are stored in push order,
5104 which is the reverse of what we have here. */
5105 bool any_regs
= false;
5106 for (int i
= nargs
; i
-- > 0; )
5107 if (argvec
[i
].reg
!= NULL_RTX
)
5109 targetm
.calls
.call_args (argvec
[i
].reg
, NULL_TREE
);
5113 targetm
.calls
.call_args (pc_rtx
, NULL_TREE
);
5115 /* Push the args that need to be pushed. */
5117 have_push_fusage
= false;
5119 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5120 are to be pushed. */
5121 for (count
= 0; count
< nargs
; count
++, argnum
--)
5123 machine_mode mode
= argvec
[argnum
].mode
;
5124 rtx val
= argvec
[argnum
].value
;
5125 rtx reg
= argvec
[argnum
].reg
;
5126 int partial
= argvec
[argnum
].partial
;
5127 unsigned int parm_align
= argvec
[argnum
].locate
.boundary
;
5128 poly_int64 lower_bound
= 0, upper_bound
= 0;
5130 if (! (reg
!= 0 && partial
== 0))
5134 if (ACCUMULATE_OUTGOING_ARGS
)
5136 /* If this is being stored into a pre-allocated, fixed-size,
5137 stack area, save any previous data at that location. */
5139 if (ARGS_GROW_DOWNWARD
)
5141 /* stack_slot is negative, but we want to index stack_usage_map
5142 with positive values. */
5143 upper_bound
= -argvec
[argnum
].locate
.slot_offset
.constant
+ 1;
5144 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
5148 lower_bound
= argvec
[argnum
].locate
.slot_offset
.constant
;
5149 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
5152 if (stack_region_maybe_used_p (lower_bound
, upper_bound
,
5153 reg_parm_stack_space
))
5155 /* We need to make a save area. */
5157 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
5158 machine_mode save_mode
5159 = int_mode_for_size (size
, 1).else_blk ();
5161 = plus_constant (Pmode
, argblock
,
5162 argvec
[argnum
].locate
.offset
.constant
);
5164 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
5166 if (save_mode
== BLKmode
)
5168 argvec
[argnum
].save_area
5169 = assign_stack_temp (BLKmode
,
5170 argvec
[argnum
].locate
.size
.constant
5173 emit_block_move (validize_mem
5174 (copy_rtx (argvec
[argnum
].save_area
)),
5177 (argvec
[argnum
].locate
.size
.constant
,
5179 BLOCK_OP_CALL_PARM
);
5183 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
5185 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
5190 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, parm_align
,
5191 partial
, reg
, 0, argblock
,
5193 (argvec
[argnum
].locate
.offset
.constant
, Pmode
)),
5194 reg_parm_stack_space
,
5195 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
), false);
5197 /* Now mark the segment we just used. */
5198 if (ACCUMULATE_OUTGOING_ARGS
)
5199 mark_stack_region_used (lower_bound
, upper_bound
);
5203 /* Indicate argument access so that alias.c knows that these
5206 use
= plus_constant (Pmode
, argblock
,
5207 argvec
[argnum
].locate
.offset
.constant
);
5208 else if (have_push_fusage
)
5212 /* When arguments are pushed, trying to tell alias.c where
5213 exactly this argument is won't work, because the
5214 auto-increment causes confusion. So we merely indicate
5215 that we access something with a known mode somewhere on
5217 use
= gen_rtx_PLUS (Pmode
, stack_pointer_rtx
,
5218 gen_rtx_SCRATCH (Pmode
));
5219 have_push_fusage
= true;
5221 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
5222 use
= gen_rtx_USE (VOIDmode
, use
);
5223 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
5229 fun
= prepare_call_address (NULL
, fun
, NULL
, &call_fusage
, 0, 0);
5231 /* Now load any reg parms into their regs. */
5233 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5234 are to be pushed. */
5235 for (count
= 0; count
< nargs
; count
++, argnum
--)
5237 machine_mode mode
= argvec
[argnum
].mode
;
5238 rtx val
= argvec
[argnum
].value
;
5239 rtx reg
= argvec
[argnum
].reg
;
5240 int partial
= argvec
[argnum
].partial
;
5242 /* Handle calls that pass values in multiple non-contiguous
5243 locations. The PA64 has examples of this for library calls. */
5244 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
5245 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
5246 else if (reg
!= 0 && partial
== 0)
5248 emit_move_insn (reg
, val
);
5249 #ifdef BLOCK_REG_PADDING
5250 poly_int64 size
= GET_MODE_SIZE (argvec
[argnum
].mode
);
5252 /* Copied from load_register_parameters. */
5254 /* Handle case where we have a value that needs shifting
5255 up to the msb. eg. a QImode value and we're padding
5256 upward on a BYTES_BIG_ENDIAN machine. */
5257 if (known_lt (size
, UNITS_PER_WORD
)
5258 && (argvec
[argnum
].locate
.where_pad
5259 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
5262 poly_int64 shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
5264 /* Assigning REG here rather than a temp makes CALL_FUSAGE
5265 report the whole reg as used. Strictly speaking, the
5266 call only uses SIZE bytes at the msb end, but it doesn't
5267 seem worth generating rtl to say that. */
5268 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
5269 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
, shift
, reg
, 1);
5271 emit_move_insn (reg
, x
);
5279 /* Any regs containing parms remain in use through the call. */
5280 for (count
= 0; count
< nargs
; count
++)
5282 rtx reg
= argvec
[count
].reg
;
5283 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
5284 use_group_regs (&call_fusage
, reg
);
5287 int partial
= argvec
[count
].partial
;
5291 gcc_assert (partial
% UNITS_PER_WORD
== 0);
5292 nregs
= partial
/ UNITS_PER_WORD
;
5293 use_regs (&call_fusage
, REGNO (reg
), nregs
);
5296 use_reg (&call_fusage
, reg
);
5300 /* Pass the function the address in which to return a structure value. */
5301 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
5303 emit_move_insn (struct_value
,
5305 force_operand (XEXP (mem_value
, 0),
5307 if (REG_P (struct_value
))
5308 use_reg (&call_fusage
, struct_value
);
5311 /* Don't allow popping to be deferred, since then
5312 cse'ing of library calls could delete a call and leave the pop. */
5314 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
5315 ? hard_libcall_value (outmode
, orgfun
) : NULL_RTX
);
5317 /* Stack must be properly aligned now. */
5318 gcc_assert (multiple_p (stack_pointer_delta
,
5319 PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
));
5321 before_call
= get_last_insn ();
5323 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
5324 will set inhibit_defer_pop to that value. */
5325 /* The return type is needed to decide how many bytes the function pops.
5326 Signedness plays no role in that, so for simplicity, we pretend it's
5327 always signed. We also assume that the list of arguments passed has
5328 no impact, so we pretend it is unknown. */
5330 emit_call_1 (fun
, NULL
,
5331 get_identifier (XSTR (orgfun
, 0)),
5332 build_function_type (tfom
, NULL_TREE
),
5333 original_args_size
.constant
, args_size
.constant
,
5335 targetm
.calls
.function_arg (args_so_far
,
5336 VOIDmode
, void_type_node
, true),
5338 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, args_so_far
);
5343 gcc_assert (GET_CODE (datum
) == SYMBOL_REF
);
5344 rtx_call_insn
*last
= last_call_insn ();
5345 add_reg_note (last
, REG_CALL_DECL
, datum
);
5348 /* Right-shift returned value if necessary. */
5349 if (!pcc_struct_value
5350 && TYPE_MODE (tfom
) != BLKmode
5351 && targetm
.calls
.return_in_msb (tfom
))
5353 shift_return_value (TYPE_MODE (tfom
), false, valreg
);
5354 valreg
= gen_rtx_REG (TYPE_MODE (tfom
), REGNO (valreg
));
5357 targetm
.calls
.end_call_args ();
5359 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
5360 that it should complain if nonvolatile values are live. For
5361 functions that cannot return, inform flow that control does not
5363 if (flags
& ECF_NORETURN
)
5365 /* The barrier note must be emitted
5366 immediately after the CALL_INSN. Some ports emit more than
5367 just a CALL_INSN above, so we must search for it here. */
5368 rtx_insn
*last
= get_last_insn ();
5369 while (!CALL_P (last
))
5371 last
= PREV_INSN (last
);
5372 /* There was no CALL_INSN? */
5373 gcc_assert (last
!= before_call
);
5376 emit_barrier_after (last
);
5379 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
5380 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
5381 if (flags
& ECF_NOTHROW
)
5383 rtx_insn
*last
= get_last_insn ();
5384 while (!CALL_P (last
))
5386 last
= PREV_INSN (last
);
5387 /* There was no CALL_INSN? */
5388 gcc_assert (last
!= before_call
);
5391 make_reg_eh_region_note_nothrow_nononlocal (last
);
5394 /* Now restore inhibit_defer_pop to its actual original value. */
5399 /* Copy the value to the right place. */
5400 if (outmode
!= VOIDmode
&& retval
)
5406 if (value
!= mem_value
)
5407 emit_move_insn (value
, mem_value
);
5409 else if (GET_CODE (valreg
) == PARALLEL
)
5412 value
= gen_reg_rtx (outmode
);
5413 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
5417 /* Convert to the proper mode if a promotion has been active. */
5418 if (GET_MODE (valreg
) != outmode
)
5420 int unsignedp
= TYPE_UNSIGNED (tfom
);
5422 gcc_assert (promote_function_mode (tfom
, outmode
, &unsignedp
,
5423 fndecl
? TREE_TYPE (fndecl
) : fntype
, 1)
5424 == GET_MODE (valreg
));
5425 valreg
= convert_modes (outmode
, GET_MODE (valreg
), valreg
, 0);
5429 emit_move_insn (value
, valreg
);
5435 if (ACCUMULATE_OUTGOING_ARGS
)
5437 #ifdef REG_PARM_STACK_SPACE
5439 restore_fixed_argument_area (save_area
, argblock
,
5440 high_to_save
, low_to_save
);
5443 /* If we saved any argument areas, restore them. */
5444 for (count
= 0; count
< nargs
; count
++)
5445 if (argvec
[count
].save_area
)
5447 machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
5448 rtx adr
= plus_constant (Pmode
, argblock
,
5449 argvec
[count
].locate
.offset
.constant
);
5450 rtx stack_area
= gen_rtx_MEM (save_mode
,
5451 memory_address (save_mode
, adr
));
5453 if (save_mode
== BLKmode
)
5454 emit_block_move (stack_area
,
5456 (copy_rtx (argvec
[count
].save_area
)),
5458 (argvec
[count
].locate
.size
.constant
, Pmode
)),
5459 BLOCK_OP_CALL_PARM
);
5461 emit_move_insn (stack_area
, argvec
[count
].save_area
);
5464 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
5465 stack_usage_map
= initial_stack_usage_map
;
5466 stack_usage_watermark
= initial_stack_usage_watermark
;
5469 free (stack_usage_map_buf
);
5476 /* Store a single argument for a function call
5477 into the register or memory area where it must be passed.
5478 *ARG describes the argument value and where to pass it.
5480 ARGBLOCK is the address of the stack-block for all the arguments,
5481 or 0 on a machine where arguments are pushed individually.
5483 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
5484 so must be careful about how the stack is used.
5486 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
5487 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
5488 that we need not worry about saving and restoring the stack.
5490 FNDECL is the declaration of the function we are calling.
5492 Return nonzero if this arg should cause sibcall failure,
5496 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
5497 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
5499 tree pval
= arg
->tree_value
;
5502 poly_int64 used
= 0;
5503 poly_int64 lower_bound
= 0, upper_bound
= 0;
5504 int sibcall_failure
= 0;
5506 if (TREE_CODE (pval
) == ERROR_MARK
)
5509 /* Push a new temporary level for any temporaries we make for
5513 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
5515 /* If this is being stored into a pre-allocated, fixed-size, stack area,
5516 save any previous data at that location. */
5517 if (argblock
&& ! variable_size
&& arg
->stack
)
5519 if (ARGS_GROW_DOWNWARD
)
5521 /* stack_slot is negative, but we want to index stack_usage_map
5522 with positive values. */
5523 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
5525 rtx offset
= XEXP (XEXP (arg
->stack_slot
, 0), 1);
5526 upper_bound
= -rtx_to_poly_int64 (offset
) + 1;
5531 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
5535 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
5537 rtx offset
= XEXP (XEXP (arg
->stack_slot
, 0), 1);
5538 lower_bound
= rtx_to_poly_int64 (offset
);
5543 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
5546 if (stack_region_maybe_used_p (lower_bound
, upper_bound
,
5547 reg_parm_stack_space
))
5549 /* We need to make a save area. */
5550 poly_uint64 size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
5551 machine_mode save_mode
5552 = int_mode_for_size (size
, 1).else_blk ();
5553 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
5554 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
5556 if (save_mode
== BLKmode
)
5559 = assign_temp (TREE_TYPE (arg
->tree_value
), 1, 1);
5560 preserve_temp_slots (arg
->save_area
);
5561 emit_block_move (validize_mem (copy_rtx (arg
->save_area
)),
5564 (arg
->locate
.size
.constant
, Pmode
)),
5565 BLOCK_OP_CALL_PARM
);
5569 arg
->save_area
= gen_reg_rtx (save_mode
);
5570 emit_move_insn (arg
->save_area
, stack_area
);
5576 /* If this isn't going to be placed on both the stack and in registers,
5577 set up the register and number of words. */
5578 if (! arg
->pass_on_stack
)
5580 if (flags
& ECF_SIBCALL
)
5581 reg
= arg
->tail_call_reg
;
5584 partial
= arg
->partial
;
5587 /* Being passed entirely in a register. We shouldn't be called in
5589 gcc_assert (reg
== 0 || partial
!= 0);
5591 /* If this arg needs special alignment, don't load the registers
5593 if (arg
->n_aligned_regs
!= 0)
5596 /* If this is being passed partially in a register, we can't evaluate
5597 it directly into its stack slot. Otherwise, we can. */
5598 if (arg
->value
== 0)
5600 /* stack_arg_under_construction is nonzero if a function argument is
5601 being evaluated directly into the outgoing argument list and
5602 expand_call must take special action to preserve the argument list
5603 if it is called recursively.
5605 For scalar function arguments stack_usage_map is sufficient to
5606 determine which stack slots must be saved and restored. Scalar
5607 arguments in general have pass_on_stack == 0.
5609 If this argument is initialized by a function which takes the
5610 address of the argument (a C++ constructor or a C function
5611 returning a BLKmode structure), then stack_usage_map is
5612 insufficient and expand_call must push the stack around the
5613 function call. Such arguments have pass_on_stack == 1.
5615 Note that it is always safe to set stack_arg_under_construction,
5616 but this generates suboptimal code if set when not needed. */
5618 if (arg
->pass_on_stack
)
5619 stack_arg_under_construction
++;
5621 arg
->value
= expand_expr (pval
,
5623 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
5624 ? NULL_RTX
: arg
->stack
,
5625 VOIDmode
, EXPAND_STACK_PARM
);
5627 /* If we are promoting object (or for any other reason) the mode
5628 doesn't agree, convert the mode. */
5630 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
5631 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
5632 arg
->value
, arg
->unsignedp
);
5634 if (arg
->pass_on_stack
)
5635 stack_arg_under_construction
--;
5638 /* Check for overlap with already clobbered argument area. */
5639 if ((flags
& ECF_SIBCALL
)
5640 && MEM_P (arg
->value
)
5641 && mem_might_overlap_already_clobbered_arg_p (XEXP (arg
->value
, 0),
5642 arg
->locate
.size
.constant
))
5643 sibcall_failure
= 1;
5645 /* Don't allow anything left on stack from computation
5646 of argument to alloca. */
5647 if (flags
& ECF_MAY_BE_ALLOCA
)
5648 do_pending_stack_adjust ();
5650 if (arg
->value
== arg
->stack
)
5651 /* If the value is already in the stack slot, we are done. */
5653 else if (arg
->mode
!= BLKmode
)
5655 unsigned int parm_align
;
5657 /* Argument is a scalar, not entirely passed in registers.
5658 (If part is passed in registers, arg->partial says how much
5659 and emit_push_insn will take care of putting it there.)
5661 Push it, and if its size is less than the
5662 amount of space allocated to it,
5663 also bump stack pointer by the additional space.
5664 Note that in C the default argument promotions
5665 will prevent such mismatches. */
5667 poly_int64 size
= (TYPE_EMPTY_P (TREE_TYPE (pval
))
5668 ? 0 : GET_MODE_SIZE (arg
->mode
));
5670 /* Compute how much space the push instruction will push.
5671 On many machines, pushing a byte will advance the stack
5672 pointer by a halfword. */
5673 #ifdef PUSH_ROUNDING
5674 size
= PUSH_ROUNDING (size
);
5678 /* Compute how much space the argument should get:
5679 round up to a multiple of the alignment for arguments. */
5680 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5682 /* At the moment we don't (need to) support ABIs for which the
5683 padding isn't known at compile time. In principle it should
5684 be easy to add though. */
5685 used
= force_align_up (size
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
5687 /* Compute the alignment of the pushed argument. */
5688 parm_align
= arg
->locate
.boundary
;
5689 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5692 poly_int64 pad
= used
- size
;
5693 unsigned int pad_align
= known_alignment (pad
) * BITS_PER_UNIT
;
5695 parm_align
= MIN (parm_align
, pad_align
);
5698 /* This isn't already where we want it on the stack, so put it there.
5699 This can either be done with push or copy insns. */
5700 if (maybe_ne (used
, 0)
5701 && !emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
),
5702 NULL_RTX
, parm_align
, partial
, reg
, used
- size
,
5703 argblock
, ARGS_SIZE_RTX (arg
->locate
.offset
),
5704 reg_parm_stack_space
,
5705 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
), true))
5706 sibcall_failure
= 1;
5708 /* Unless this is a partially-in-register argument, the argument is now
5711 arg
->value
= arg
->stack
;
5715 /* BLKmode, at least partly to be pushed. */
5717 unsigned int parm_align
;
5721 /* Pushing a nonscalar.
5722 If part is passed in registers, PARTIAL says how much
5723 and emit_push_insn will take care of putting it there. */
5725 /* Round its size up to a multiple
5726 of the allocation unit for arguments. */
5728 if (arg
->locate
.size
.var
!= 0)
5731 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
5735 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
5736 for BLKmode is careful to avoid it. */
5737 excess
= (arg
->locate
.size
.constant
5738 - arg_int_size_in_bytes (TREE_TYPE (pval
))
5740 size_rtx
= expand_expr (arg_size_in_bytes (TREE_TYPE (pval
)),
5741 NULL_RTX
, TYPE_MODE (sizetype
),
5745 parm_align
= arg
->locate
.boundary
;
5747 /* When an argument is padded down, the block is aligned to
5748 PARM_BOUNDARY, but the actual argument isn't. */
5749 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5752 if (arg
->locate
.size
.var
)
5753 parm_align
= BITS_PER_UNIT
;
5756 unsigned int excess_align
5757 = known_alignment (excess
) * BITS_PER_UNIT
;
5758 if (excess_align
!= 0)
5759 parm_align
= MIN (parm_align
, excess_align
);
5763 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
5765 /* emit_push_insn might not work properly if arg->value and
5766 argblock + arg->locate.offset areas overlap. */
5770 if (strip_offset (XEXP (x
, 0), &i
)
5771 == crtl
->args
.internal_arg_pointer
)
5773 /* arg.locate doesn't contain the pretend_args_size offset,
5774 it's part of argblock. Ensure we don't count it in I. */
5775 if (STACK_GROWS_DOWNWARD
)
5776 i
-= crtl
->args
.pretend_args_size
;
5778 i
+= crtl
->args
.pretend_args_size
;
5780 /* expand_call should ensure this. */
5781 gcc_assert (!arg
->locate
.offset
.var
5782 && arg
->locate
.size
.var
== 0);
5783 poly_int64 size_val
= rtx_to_poly_int64 (size_rtx
);
5785 if (known_eq (arg
->locate
.offset
.constant
, i
))
5787 /* Even though they appear to be at the same location,
5788 if part of the outgoing argument is in registers,
5789 they aren't really at the same location. Check for
5790 this by making sure that the incoming size is the
5791 same as the outgoing size. */
5792 if (maybe_ne (arg
->locate
.size
.constant
, size_val
))
5793 sibcall_failure
= 1;
5795 else if (maybe_in_range_p (arg
->locate
.offset
.constant
,
5797 sibcall_failure
= 1;
5798 /* Use arg->locate.size.constant instead of size_rtx
5799 because we only care about the part of the argument
5801 else if (maybe_in_range_p (i
, arg
->locate
.offset
.constant
,
5802 arg
->locate
.size
.constant
))
5803 sibcall_failure
= 1;
5807 if (!CONST_INT_P (size_rtx
) || INTVAL (size_rtx
) != 0)
5808 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
5809 parm_align
, partial
, reg
, excess
, argblock
,
5810 ARGS_SIZE_RTX (arg
->locate
.offset
),
5811 reg_parm_stack_space
,
5812 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
), false);
5814 /* Unless this is a partially-in-register argument, the argument is now
5817 ??? Unlike the case above, in which we want the actual
5818 address of the data, so that we can load it directly into a
5819 register, here we want the address of the stack slot, so that
5820 it's properly aligned for word-by-word copying or something
5821 like that. It's not clear that this is always correct. */
5823 arg
->value
= arg
->stack_slot
;
5826 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
5828 tree type
= TREE_TYPE (arg
->tree_value
);
5830 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
5831 int_size_in_bytes (type
));
5834 /* Mark all slots this store used. */
5835 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
5836 && argblock
&& ! variable_size
&& arg
->stack
)
5837 mark_stack_region_used (lower_bound
, upper_bound
);
5839 /* Once we have pushed something, pops can't safely
5840 be deferred during the rest of the arguments. */
5843 /* Free any temporary slots made in processing this argument. */
5846 return sibcall_failure
;
5849 /* Nonzero if we do not know how to pass TYPE solely in registers. */
5852 must_pass_in_stack_var_size (machine_mode mode ATTRIBUTE_UNUSED
,
5858 /* If the type has variable size... */
5859 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
5862 /* If the type is marked as addressable (it is required
5863 to be constructed into the stack)... */
5864 if (TREE_ADDRESSABLE (type
))
5870 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5871 takes trailing padding of a structure into account. */
5872 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5875 must_pass_in_stack_var_size_or_pad (machine_mode mode
, const_tree type
)
5880 /* If the type has variable size... */
5881 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
5884 /* If the type is marked as addressable (it is required
5885 to be constructed into the stack)... */
5886 if (TREE_ADDRESSABLE (type
))
5889 if (TYPE_EMPTY_P (type
))
5892 /* If the padding and mode of the type is such that a copy into
5893 a register would put it into the wrong part of the register. */
5895 && int_size_in_bytes (type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
5896 && (targetm
.calls
.function_arg_padding (mode
, type
)
5897 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
5903 /* Tell the garbage collector about GTY markers in this source file. */
5904 #include "gt-calls.h"