1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989-2018 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 value is passed in neither reg nor stack, this field holds a number
86 of a special slot to be used. */
88 /* For pointer bounds hold an index of parm bounds are bound to. -1 if
89 there is no such pointer. */
91 /* If pointer_arg refers a structure, then pointer_offset holds an offset
92 of a pointer in this structure. */
94 /* If REG was promoted from the actual mode of the argument expression,
95 indicates whether the promotion is sign- or zero-extended. */
97 /* Number of bytes to put in registers. 0 means put the whole arg
98 in registers. Also 0 if not passed in registers. */
100 /* Nonzero if argument must be passed on stack.
101 Note that some arguments may be passed on the stack
102 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
103 pass_on_stack identifies arguments that *cannot* go in registers. */
105 /* Some fields packaged up for locate_and_pad_parm. */
106 struct locate_and_pad_arg_data locate
;
107 /* Location on the stack at which parameter should be stored. The store
108 has already been done if STACK == VALUE. */
110 /* Location on the stack of the start of this argument slot. This can
111 differ from STACK if this arg pads downward. This location is known
112 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
114 /* Place that this stack area has been saved, if needed. */
116 /* If an argument's alignment does not permit direct copying into registers,
117 copy in smaller-sized pieces into pseudos. These are stored in a
118 block pointed to by this field. The next field says how many
119 word-sized pseudos we made. */
124 /* A vector of one char per byte of stack space. A byte if nonzero if
125 the corresponding stack location has been used.
126 This vector is used to prevent a function call within an argument from
127 clobbering any stack already set up. */
128 static char *stack_usage_map
;
130 /* Size of STACK_USAGE_MAP. */
131 static unsigned int highest_outgoing_arg_in_use
;
133 /* Assume that any stack location at this byte index is used,
134 without checking the contents of stack_usage_map. */
135 static unsigned HOST_WIDE_INT stack_usage_watermark
= HOST_WIDE_INT_M1U
;
137 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
138 stack location's tail call argument has been already stored into the stack.
139 This bitmap is used to prevent sibling call optimization if function tries
140 to use parent's incoming argument slots when they have been already
141 overwritten with tail call arguments. */
142 static sbitmap stored_args_map
;
144 /* Assume that any virtual-incoming location at this byte index has been
145 stored, without checking the contents of stored_args_map. */
146 static unsigned HOST_WIDE_INT stored_args_watermark
;
148 /* stack_arg_under_construction is nonzero when an argument may be
149 initialized with a constructor call (including a C function that
150 returns a BLKmode struct) and expand_call must take special action
151 to make sure the object being constructed does not overlap the
152 argument list for the constructor call. */
153 static int stack_arg_under_construction
;
155 static void precompute_register_parameters (int, struct arg_data
*, int *);
156 static int store_one_arg (struct arg_data
*, rtx
, int, int, int);
157 static void store_unaligned_arguments_into_pseudos (struct arg_data
*, int);
158 static int finalize_must_preallocate (int, int, struct arg_data
*,
160 static void precompute_arguments (int, struct arg_data
*);
161 static void compute_argument_addresses (struct arg_data
*, rtx
, int);
162 static rtx
rtx_for_function_call (tree
, tree
);
163 static void load_register_parameters (struct arg_data
*, int, rtx
*, int,
165 static int special_function_p (const_tree
, int);
166 static int check_sibcall_argument_overlap_1 (rtx
);
167 static int check_sibcall_argument_overlap (rtx_insn
*, struct arg_data
*, int);
169 static tree
split_complex_types (tree
);
171 #ifdef REG_PARM_STACK_SPACE
172 static rtx
save_fixed_argument_area (int, rtx
, int *, int *);
173 static void restore_fixed_argument_area (rtx
, rtx
, int, int);
176 /* Return true if bytes [LOWER_BOUND, UPPER_BOUND) of the outgoing
177 stack region might already be in use. */
180 stack_region_maybe_used_p (poly_uint64 lower_bound
, poly_uint64 upper_bound
,
181 unsigned int reg_parm_stack_space
)
183 unsigned HOST_WIDE_INT const_lower
, const_upper
;
184 const_lower
= constant_lower_bound (lower_bound
);
185 if (!upper_bound
.is_constant (&const_upper
))
186 const_upper
= HOST_WIDE_INT_M1U
;
188 if (const_upper
> stack_usage_watermark
)
191 /* Don't worry about things in the fixed argument area;
192 it has already been saved. */
193 const_lower
= MAX (const_lower
, reg_parm_stack_space
);
194 const_upper
= MIN (const_upper
, highest_outgoing_arg_in_use
);
195 for (unsigned HOST_WIDE_INT i
= const_lower
; i
< const_upper
; ++i
)
196 if (stack_usage_map
[i
])
201 /* Record that bytes [LOWER_BOUND, UPPER_BOUND) of the outgoing
202 stack region are now in use. */
205 mark_stack_region_used (poly_uint64 lower_bound
, poly_uint64 upper_bound
)
207 unsigned HOST_WIDE_INT const_lower
, const_upper
;
208 const_lower
= constant_lower_bound (lower_bound
);
209 if (upper_bound
.is_constant (&const_upper
))
210 for (unsigned HOST_WIDE_INT i
= const_lower
; i
< const_upper
; ++i
)
211 stack_usage_map
[i
] = 1;
213 stack_usage_watermark
= MIN (stack_usage_watermark
, const_lower
);
216 /* Force FUNEXP into a form suitable for the address of a CALL,
217 and return that as an rtx. Also load the static chain register
218 if FNDECL is a nested function.
220 CALL_FUSAGE points to a variable holding the prospective
221 CALL_INSN_FUNCTION_USAGE information. */
224 prepare_call_address (tree fndecl_or_type
, rtx funexp
, rtx static_chain_value
,
225 rtx
*call_fusage
, int reg_parm_seen
, int flags
)
227 /* Make a valid memory address and copy constants through pseudo-regs,
228 but not for a constant address if -fno-function-cse. */
229 if (GET_CODE (funexp
) != SYMBOL_REF
)
231 /* If it's an indirect call by descriptor, generate code to perform
232 runtime identification of the pointer and load the descriptor. */
233 if ((flags
& ECF_BY_DESCRIPTOR
) && !flag_trampolines
)
235 const int bit_val
= targetm
.calls
.custom_function_descriptors
;
236 rtx call_lab
= gen_label_rtx ();
238 gcc_assert (fndecl_or_type
&& TYPE_P (fndecl_or_type
));
240 = build_decl (UNKNOWN_LOCATION
, FUNCTION_DECL
, NULL_TREE
,
242 DECL_STATIC_CHAIN (fndecl_or_type
) = 1;
243 rtx chain
= targetm
.calls
.static_chain (fndecl_or_type
, false);
245 if (GET_MODE (funexp
) != Pmode
)
246 funexp
= convert_memory_address (Pmode
, funexp
);
248 /* Avoid long live ranges around function calls. */
249 funexp
= copy_to_mode_reg (Pmode
, funexp
);
252 emit_insn (gen_rtx_CLOBBER (VOIDmode
, chain
));
254 /* Emit the runtime identification pattern. */
255 rtx mask
= gen_rtx_AND (Pmode
, funexp
, GEN_INT (bit_val
));
256 emit_cmp_and_jump_insns (mask
, const0_rtx
, EQ
, NULL_RTX
, Pmode
, 1,
259 /* Statically predict the branch to very likely taken. */
260 rtx_insn
*insn
= get_last_insn ();
262 predict_insn_def (insn
, PRED_BUILTIN_EXPECT
, TAKEN
);
264 /* Load the descriptor. */
265 rtx mem
= gen_rtx_MEM (ptr_mode
,
266 plus_constant (Pmode
, funexp
, - bit_val
));
267 MEM_NOTRAP_P (mem
) = 1;
268 mem
= convert_memory_address (Pmode
, mem
);
269 emit_move_insn (chain
, mem
);
271 mem
= gen_rtx_MEM (ptr_mode
,
272 plus_constant (Pmode
, funexp
,
273 POINTER_SIZE
/ BITS_PER_UNIT
275 MEM_NOTRAP_P (mem
) = 1;
276 mem
= convert_memory_address (Pmode
, mem
);
277 emit_move_insn (funexp
, mem
);
279 emit_label (call_lab
);
283 use_reg (call_fusage
, chain
);
284 STATIC_CHAIN_REG_P (chain
) = 1;
287 /* Make sure we're not going to be overwritten below. */
288 gcc_assert (!static_chain_value
);
291 /* If we are using registers for parameters, force the
292 function address into a register now. */
293 funexp
= ((reg_parm_seen
294 && targetm
.small_register_classes_for_mode_p (FUNCTION_MODE
))
295 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
296 : memory_address (FUNCTION_MODE
, funexp
));
300 /* funexp could be a SYMBOL_REF represents a function pointer which is
301 of ptr_mode. In this case, it should be converted into address mode
302 to be a valid address for memory rtx pattern. See PR 64971. */
303 if (GET_MODE (funexp
) != Pmode
)
304 funexp
= convert_memory_address (Pmode
, funexp
);
306 if (!(flags
& ECF_SIBCALL
))
308 if (!NO_FUNCTION_CSE
&& optimize
&& ! flag_no_function_cse
)
309 funexp
= force_reg (Pmode
, funexp
);
313 if (static_chain_value
!= 0
314 && (TREE_CODE (fndecl_or_type
) != FUNCTION_DECL
315 || DECL_STATIC_CHAIN (fndecl_or_type
)))
319 chain
= targetm
.calls
.static_chain (fndecl_or_type
, false);
320 static_chain_value
= convert_memory_address (Pmode
, static_chain_value
);
322 emit_move_insn (chain
, static_chain_value
);
325 use_reg (call_fusage
, chain
);
326 STATIC_CHAIN_REG_P (chain
) = 1;
333 /* Generate instructions to call function FUNEXP,
334 and optionally pop the results.
335 The CALL_INSN is the first insn generated.
337 FNDECL is the declaration node of the function. This is given to the
338 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
341 FUNTYPE is the data type of the function. This is given to the hook
342 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
343 own args. We used to allow an identifier for library functions, but
344 that doesn't work when the return type is an aggregate type and the
345 calling convention says that the pointer to this aggregate is to be
346 popped by the callee.
348 STACK_SIZE is the number of bytes of arguments on the stack,
349 ROUNDED_STACK_SIZE is that number rounded up to
350 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
351 both to put into the call insn and to generate explicit popping
354 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
355 It is zero if this call doesn't want a structure value.
357 NEXT_ARG_REG is the rtx that results from executing
358 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
359 just after all the args have had their registers assigned.
360 This could be whatever you like, but normally it is the first
361 arg-register beyond those used for args in this call,
362 or 0 if all the arg-registers are used in this call.
363 It is passed on to `gen_call' so you can put this info in the call insn.
365 VALREG is a hard register in which a value is returned,
366 or 0 if the call does not return a value.
368 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
369 the args to this call were processed.
370 We restore `inhibit_defer_pop' to that value.
372 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
373 denote registers used by the called function. */
376 emit_call_1 (rtx funexp
, tree fntree ATTRIBUTE_UNUSED
, tree fndecl ATTRIBUTE_UNUSED
,
377 tree funtype ATTRIBUTE_UNUSED
,
378 poly_int64 stack_size ATTRIBUTE_UNUSED
,
379 poly_int64 rounded_stack_size
,
380 poly_int64 struct_value_size ATTRIBUTE_UNUSED
,
381 rtx next_arg_reg ATTRIBUTE_UNUSED
, rtx valreg
,
382 int old_inhibit_defer_pop
, rtx call_fusage
, int ecf_flags
,
383 cumulative_args_t args_so_far ATTRIBUTE_UNUSED
)
385 rtx rounded_stack_size_rtx
= gen_int_mode (rounded_stack_size
, Pmode
);
386 rtx call
, funmem
, pat
;
387 int already_popped
= 0;
388 poly_int64 n_popped
= 0;
390 /* Sibling call patterns never pop arguments (no sibcall(_value)_pop
391 patterns exist). Any popping that the callee does on return will
392 be from our caller's frame rather than ours. */
393 if (!(ecf_flags
& ECF_SIBCALL
))
395 n_popped
+= targetm
.calls
.return_pops_args (fndecl
, funtype
, stack_size
);
397 #ifdef CALL_POPS_ARGS
398 n_popped
+= CALL_POPS_ARGS (*get_cumulative_args (args_so_far
));
402 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
403 and we don't want to load it into a register as an optimization,
404 because prepare_call_address already did it if it should be done. */
405 if (GET_CODE (funexp
) != SYMBOL_REF
)
406 funexp
= memory_address (FUNCTION_MODE
, funexp
);
408 funmem
= gen_rtx_MEM (FUNCTION_MODE
, funexp
);
409 if (fndecl
&& TREE_CODE (fndecl
) == FUNCTION_DECL
)
413 /* Although a built-in FUNCTION_DECL and its non-__builtin
414 counterpart compare equal and get a shared mem_attrs, they
415 produce different dump output in compare-debug compilations,
416 if an entry gets garbage collected in one compilation, then
417 adds a different (but equivalent) entry, while the other
418 doesn't run the garbage collector at the same spot and then
419 shares the mem_attr with the equivalent entry. */
420 if (DECL_BUILT_IN_CLASS (t
) == BUILT_IN_NORMAL
)
422 tree t2
= builtin_decl_explicit (DECL_FUNCTION_CODE (t
));
427 set_mem_expr (funmem
, t
);
430 set_mem_expr (funmem
, build_simple_mem_ref (CALL_EXPR_FN (fntree
)));
432 if (ecf_flags
& ECF_SIBCALL
)
435 pat
= targetm
.gen_sibcall_value (valreg
, funmem
,
436 rounded_stack_size_rtx
,
437 next_arg_reg
, NULL_RTX
);
439 pat
= targetm
.gen_sibcall (funmem
, rounded_stack_size_rtx
,
441 gen_int_mode (struct_value_size
, Pmode
));
443 /* If the target has "call" or "call_value" insns, then prefer them
444 if no arguments are actually popped. If the target does not have
445 "call" or "call_value" insns, then we must use the popping versions
446 even if the call has no arguments to pop. */
447 else if (maybe_ne (n_popped
, 0)
449 ? targetm
.have_call_value ()
450 : targetm
.have_call ()))
452 rtx n_pop
= gen_int_mode (n_popped
, Pmode
);
454 /* If this subroutine pops its own args, record that in the call insn
455 if possible, for the sake of frame pointer elimination. */
458 pat
= targetm
.gen_call_value_pop (valreg
, funmem
,
459 rounded_stack_size_rtx
,
460 next_arg_reg
, n_pop
);
462 pat
= targetm
.gen_call_pop (funmem
, rounded_stack_size_rtx
,
463 next_arg_reg
, n_pop
);
470 pat
= targetm
.gen_call_value (valreg
, funmem
, rounded_stack_size_rtx
,
471 next_arg_reg
, NULL_RTX
);
473 pat
= targetm
.gen_call (funmem
, rounded_stack_size_rtx
, next_arg_reg
,
474 gen_int_mode (struct_value_size
, Pmode
));
478 /* Find the call we just emitted. */
479 rtx_call_insn
*call_insn
= last_call_insn ();
481 /* Some target create a fresh MEM instead of reusing the one provided
482 above. Set its MEM_EXPR. */
483 call
= get_call_rtx_from (call_insn
);
485 && MEM_EXPR (XEXP (call
, 0)) == NULL_TREE
486 && MEM_EXPR (funmem
) != NULL_TREE
)
487 set_mem_expr (XEXP (call
, 0), MEM_EXPR (funmem
));
489 /* Put the register usage information there. */
490 add_function_usage_to (call_insn
, call_fusage
);
492 /* If this is a const call, then set the insn's unchanging bit. */
493 if (ecf_flags
& ECF_CONST
)
494 RTL_CONST_CALL_P (call_insn
) = 1;
496 /* If this is a pure call, then set the insn's unchanging bit. */
497 if (ecf_flags
& ECF_PURE
)
498 RTL_PURE_CALL_P (call_insn
) = 1;
500 /* If this is a const call, then set the insn's unchanging bit. */
501 if (ecf_flags
& ECF_LOOPING_CONST_OR_PURE
)
502 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn
) = 1;
504 /* Create a nothrow REG_EH_REGION note, if needed. */
505 make_reg_eh_region_note (call_insn
, ecf_flags
, 0);
507 if (ecf_flags
& ECF_NORETURN
)
508 add_reg_note (call_insn
, REG_NORETURN
, const0_rtx
);
510 if (ecf_flags
& ECF_RETURNS_TWICE
)
512 add_reg_note (call_insn
, REG_SETJMP
, const0_rtx
);
513 cfun
->calls_setjmp
= 1;
516 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
518 /* Restore this now, so that we do defer pops for this call's args
519 if the context of the call as a whole permits. */
520 inhibit_defer_pop
= old_inhibit_defer_pop
;
522 if (maybe_ne (n_popped
, 0))
525 CALL_INSN_FUNCTION_USAGE (call_insn
)
526 = gen_rtx_EXPR_LIST (VOIDmode
,
527 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
528 CALL_INSN_FUNCTION_USAGE (call_insn
));
529 rounded_stack_size
-= n_popped
;
530 rounded_stack_size_rtx
= gen_int_mode (rounded_stack_size
, Pmode
);
531 stack_pointer_delta
-= n_popped
;
533 add_args_size_note (call_insn
, stack_pointer_delta
);
535 /* If popup is needed, stack realign must use DRAP */
536 if (SUPPORTS_STACK_ALIGNMENT
)
537 crtl
->need_drap
= true;
539 /* For noreturn calls when not accumulating outgoing args force
540 REG_ARGS_SIZE note to prevent crossjumping of calls with different
542 else if (!ACCUMULATE_OUTGOING_ARGS
&& (ecf_flags
& ECF_NORETURN
) != 0)
543 add_args_size_note (call_insn
, stack_pointer_delta
);
545 if (!ACCUMULATE_OUTGOING_ARGS
)
547 /* If returning from the subroutine does not automatically pop the args,
548 we need an instruction to pop them sooner or later.
549 Perhaps do it now; perhaps just record how much space to pop later.
551 If returning from the subroutine does pop the args, indicate that the
552 stack pointer will be changed. */
554 if (maybe_ne (rounded_stack_size
, 0))
556 if (ecf_flags
& ECF_NORETURN
)
557 /* Just pretend we did the pop. */
558 stack_pointer_delta
-= rounded_stack_size
;
559 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
560 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
561 pending_stack_adjust
+= rounded_stack_size
;
563 adjust_stack (rounded_stack_size_rtx
);
566 /* When we accumulate outgoing args, we must avoid any stack manipulations.
567 Restore the stack pointer to its original value now. Usually
568 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
569 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
570 popping variants of functions exist as well.
572 ??? We may optimize similar to defer_pop above, but it is
573 probably not worthwhile.
575 ??? It will be worthwhile to enable combine_stack_adjustments even for
577 else if (maybe_ne (n_popped
, 0))
578 anti_adjust_stack (gen_int_mode (n_popped
, Pmode
));
581 /* Determine if the function identified by FNDECL is one with
582 special properties we wish to know about. Modify FLAGS accordingly.
584 For example, if the function might return more than one time (setjmp), then
585 set ECF_RETURNS_TWICE.
587 Set ECF_MAY_BE_ALLOCA for any memory allocation function that might allocate
588 space from the stack such as alloca. */
591 special_function_p (const_tree fndecl
, int flags
)
593 tree name_decl
= DECL_NAME (fndecl
);
595 if (fndecl
&& name_decl
596 && IDENTIFIER_LENGTH (name_decl
) <= 11
597 /* Exclude functions not at the file scope, or not `extern',
598 since they are not the magic functions we would otherwise
600 FIXME: this should be handled with attributes, not with this
601 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
602 because you can declare fork() inside a function if you
604 && (DECL_CONTEXT (fndecl
) == NULL_TREE
605 || TREE_CODE (DECL_CONTEXT (fndecl
)) == TRANSLATION_UNIT_DECL
)
606 && TREE_PUBLIC (fndecl
))
608 const char *name
= IDENTIFIER_POINTER (name_decl
);
609 const char *tname
= name
;
611 /* We assume that alloca will always be called by name. It
612 makes no sense to pass it as a pointer-to-function to
613 anything that does not understand its behavior. */
614 if (IDENTIFIER_LENGTH (name_decl
) == 6
616 && ! strcmp (name
, "alloca"))
617 flags
|= ECF_MAY_BE_ALLOCA
;
619 /* Disregard prefix _ or __. */
628 /* ECF_RETURNS_TWICE is safe even for -ffreestanding. */
629 if (! strcmp (tname
, "setjmp")
630 || ! strcmp (tname
, "sigsetjmp")
631 || ! strcmp (name
, "savectx")
632 || ! strcmp (name
, "vfork")
633 || ! strcmp (name
, "getcontext"))
634 flags
|= ECF_RETURNS_TWICE
;
637 if (DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
638 && ALLOCA_FUNCTION_CODE_P (DECL_FUNCTION_CODE (fndecl
)))
639 flags
|= ECF_MAY_BE_ALLOCA
;
644 /* Similar to special_function_p; return a set of ERF_ flags for the
647 decl_return_flags (tree fndecl
)
650 tree type
= TREE_TYPE (fndecl
);
654 attr
= lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type
));
658 attr
= TREE_VALUE (TREE_VALUE (attr
));
659 if (!attr
|| TREE_STRING_LENGTH (attr
) < 1)
662 switch (TREE_STRING_POINTER (attr
)[0])
668 return ERF_RETURNS_ARG
| (TREE_STRING_POINTER (attr
)[0] - '1');
679 /* Return nonzero when FNDECL represents a call to setjmp. */
682 setjmp_call_p (const_tree fndecl
)
684 if (DECL_IS_RETURNS_TWICE (fndecl
))
685 return ECF_RETURNS_TWICE
;
686 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
690 /* Return true if STMT may be an alloca call. */
693 gimple_maybe_alloca_call_p (const gimple
*stmt
)
697 if (!is_gimple_call (stmt
))
700 fndecl
= gimple_call_fndecl (stmt
);
701 if (fndecl
&& (special_function_p (fndecl
, 0) & ECF_MAY_BE_ALLOCA
))
707 /* Return true if STMT is a builtin alloca call. */
710 gimple_alloca_call_p (const gimple
*stmt
)
714 if (!is_gimple_call (stmt
))
717 fndecl
= gimple_call_fndecl (stmt
);
718 if (fndecl
&& DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
719 switch (DECL_FUNCTION_CODE (fndecl
))
721 CASE_BUILT_IN_ALLOCA
:
722 return gimple_call_num_args (stmt
) > 0;
730 /* Return true when exp contains a builtin alloca call. */
733 alloca_call_p (const_tree exp
)
736 if (TREE_CODE (exp
) == CALL_EXPR
737 && (fndecl
= get_callee_fndecl (exp
))
738 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
739 switch (DECL_FUNCTION_CODE (fndecl
))
741 CASE_BUILT_IN_ALLOCA
:
750 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
751 function. Return FALSE otherwise. */
754 is_tm_builtin (const_tree fndecl
)
759 if (decl_is_tm_clone (fndecl
))
762 if (DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
764 switch (DECL_FUNCTION_CODE (fndecl
))
766 case BUILT_IN_TM_COMMIT
:
767 case BUILT_IN_TM_COMMIT_EH
:
768 case BUILT_IN_TM_ABORT
:
769 case BUILT_IN_TM_IRREVOCABLE
:
770 case BUILT_IN_TM_GETTMCLONE_IRR
:
771 case BUILT_IN_TM_MEMCPY
:
772 case BUILT_IN_TM_MEMMOVE
:
773 case BUILT_IN_TM_MEMSET
:
774 CASE_BUILT_IN_TM_STORE (1):
775 CASE_BUILT_IN_TM_STORE (2):
776 CASE_BUILT_IN_TM_STORE (4):
777 CASE_BUILT_IN_TM_STORE (8):
778 CASE_BUILT_IN_TM_STORE (FLOAT
):
779 CASE_BUILT_IN_TM_STORE (DOUBLE
):
780 CASE_BUILT_IN_TM_STORE (LDOUBLE
):
781 CASE_BUILT_IN_TM_STORE (M64
):
782 CASE_BUILT_IN_TM_STORE (M128
):
783 CASE_BUILT_IN_TM_STORE (M256
):
784 CASE_BUILT_IN_TM_LOAD (1):
785 CASE_BUILT_IN_TM_LOAD (2):
786 CASE_BUILT_IN_TM_LOAD (4):
787 CASE_BUILT_IN_TM_LOAD (8):
788 CASE_BUILT_IN_TM_LOAD (FLOAT
):
789 CASE_BUILT_IN_TM_LOAD (DOUBLE
):
790 CASE_BUILT_IN_TM_LOAD (LDOUBLE
):
791 CASE_BUILT_IN_TM_LOAD (M64
):
792 CASE_BUILT_IN_TM_LOAD (M128
):
793 CASE_BUILT_IN_TM_LOAD (M256
):
794 case BUILT_IN_TM_LOG
:
795 case BUILT_IN_TM_LOG_1
:
796 case BUILT_IN_TM_LOG_2
:
797 case BUILT_IN_TM_LOG_4
:
798 case BUILT_IN_TM_LOG_8
:
799 case BUILT_IN_TM_LOG_FLOAT
:
800 case BUILT_IN_TM_LOG_DOUBLE
:
801 case BUILT_IN_TM_LOG_LDOUBLE
:
802 case BUILT_IN_TM_LOG_M64
:
803 case BUILT_IN_TM_LOG_M128
:
804 case BUILT_IN_TM_LOG_M256
:
813 /* Detect flags (function attributes) from the function decl or type node. */
816 flags_from_decl_or_type (const_tree exp
)
822 /* The function exp may have the `malloc' attribute. */
823 if (DECL_IS_MALLOC (exp
))
826 /* The function exp may have the `returns_twice' attribute. */
827 if (DECL_IS_RETURNS_TWICE (exp
))
828 flags
|= ECF_RETURNS_TWICE
;
830 /* Process the pure and const attributes. */
831 if (TREE_READONLY (exp
))
833 if (DECL_PURE_P (exp
))
835 if (DECL_LOOPING_CONST_OR_PURE_P (exp
))
836 flags
|= ECF_LOOPING_CONST_OR_PURE
;
838 if (DECL_IS_NOVOPS (exp
))
840 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp
)))
842 if (lookup_attribute ("cold", DECL_ATTRIBUTES (exp
)))
845 if (TREE_NOTHROW (exp
))
846 flags
|= ECF_NOTHROW
;
850 if (is_tm_builtin (exp
))
851 flags
|= ECF_TM_BUILTIN
;
852 else if ((flags
& (ECF_CONST
|ECF_NOVOPS
)) != 0
853 || lookup_attribute ("transaction_pure",
854 TYPE_ATTRIBUTES (TREE_TYPE (exp
))))
855 flags
|= ECF_TM_PURE
;
858 flags
= special_function_p (exp
, flags
);
860 else if (TYPE_P (exp
))
862 if (TYPE_READONLY (exp
))
866 && ((flags
& ECF_CONST
) != 0
867 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp
))))
868 flags
|= ECF_TM_PURE
;
873 if (TREE_THIS_VOLATILE (exp
))
875 flags
|= ECF_NORETURN
;
876 if (flags
& (ECF_CONST
|ECF_PURE
))
877 flags
|= ECF_LOOPING_CONST_OR_PURE
;
883 /* Detect flags from a CALL_EXPR. */
886 call_expr_flags (const_tree t
)
889 tree decl
= get_callee_fndecl (t
);
892 flags
= flags_from_decl_or_type (decl
);
893 else if (CALL_EXPR_FN (t
) == NULL_TREE
)
894 flags
= internal_fn_flags (CALL_EXPR_IFN (t
));
897 tree type
= TREE_TYPE (CALL_EXPR_FN (t
));
898 if (type
&& TREE_CODE (type
) == POINTER_TYPE
)
899 flags
= flags_from_decl_or_type (TREE_TYPE (type
));
902 if (CALL_EXPR_BY_DESCRIPTOR (t
))
903 flags
|= ECF_BY_DESCRIPTOR
;
909 /* Return true if TYPE should be passed by invisible reference. */
912 pass_by_reference (CUMULATIVE_ARGS
*ca
, machine_mode mode
,
913 tree type
, bool named_arg
)
917 /* If this type contains non-trivial constructors, then it is
918 forbidden for the middle-end to create any new copies. */
919 if (TREE_ADDRESSABLE (type
))
922 /* GCC post 3.4 passes *all* variable sized types by reference. */
923 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
926 /* If a record type should be passed the same as its first (and only)
927 member, use the type and mode of that member. */
928 if (TREE_CODE (type
) == RECORD_TYPE
&& TYPE_TRANSPARENT_AGGR (type
))
930 type
= TREE_TYPE (first_field (type
));
931 mode
= TYPE_MODE (type
);
935 return targetm
.calls
.pass_by_reference (pack_cumulative_args (ca
), mode
,
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 alloc_object_size_limit
1226 = build_int_cst (size_type_node
, warn_alloc_size_limit
);
1228 return alloc_object_size_limit
;
1231 /* Return true when EXP's range can be determined and set RANGE[] to it
1232 after adjusting it if necessary to make EXP a represents a valid size
1233 of object, or a valid size argument to an allocation function declared
1234 with attribute alloc_size (whose argument may be signed), or to a string
1235 manipulation function like memset. When ALLOW_ZERO is true, allow
1236 returning a range of [0, 0] for a size in an anti-range [1, N] where
1237 N > PTRDIFF_MAX. A zero range is a (nearly) invalid argument to
1238 allocation functions like malloc but it is a valid argument to
1239 functions like memset. */
1242 get_size_range (tree exp
, tree range
[2], bool allow_zero
/* = false */)
1244 if (tree_fits_uhwi_p (exp
))
1246 /* EXP is a constant. */
1247 range
[0] = range
[1] = exp
;
1251 tree exptype
= TREE_TYPE (exp
);
1252 bool integral
= INTEGRAL_TYPE_P (exptype
);
1255 enum value_range_type range_type
;
1258 range_type
= determine_value_range (exp
, &min
, &max
);
1260 range_type
= VR_VARYING
;
1262 if (range_type
== VR_VARYING
)
1266 /* Use the full range of the type of the expression when
1267 no value range information is available. */
1268 range
[0] = TYPE_MIN_VALUE (exptype
);
1269 range
[1] = TYPE_MAX_VALUE (exptype
);
1273 range
[0] = NULL_TREE
;
1274 range
[1] = NULL_TREE
;
1278 unsigned expprec
= TYPE_PRECISION (exptype
);
1280 bool signed_p
= !TYPE_UNSIGNED (exptype
);
1282 if (range_type
== VR_ANTI_RANGE
)
1286 if (wi::les_p (max
, 0))
1288 /* EXP is not in a strictly negative range. That means
1289 it must be in some (not necessarily strictly) positive
1290 range which includes zero. Since in signed to unsigned
1291 conversions negative values end up converted to large
1292 positive values, and otherwise they are not valid sizes,
1293 the resulting range is in both cases [0, TYPE_MAX]. */
1294 min
= wi::zero (expprec
);
1295 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1297 else if (wi::les_p (min
- 1, 0))
1299 /* EXP is not in a negative-positive range. That means EXP
1300 is either negative, or greater than max. Since negative
1301 sizes are invalid make the range [MAX + 1, TYPE_MAX]. */
1303 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1308 min
= wi::zero (expprec
);
1311 else if (wi::eq_p (0, min
- 1))
1313 /* EXP is unsigned and not in the range [1, MAX]. That means
1314 it's either zero or greater than MAX. Even though 0 would
1315 normally be detected by -Walloc-zero, unless ALLOW_ZERO
1316 is true, set the range to [MAX, TYPE_MAX] so that when MAX
1317 is greater than the limit the whole range is diagnosed. */
1319 min
= max
= wi::zero (expprec
);
1323 max
= wi::to_wide (TYPE_MAX_VALUE (exptype
));
1329 min
= wi::zero (expprec
);
1333 range
[0] = wide_int_to_tree (exptype
, min
);
1334 range
[1] = wide_int_to_tree (exptype
, max
);
1339 /* Diagnose a call EXP to function FN decorated with attribute alloc_size
1340 whose argument numbers given by IDX with values given by ARGS exceed
1341 the maximum object size or cause an unsigned oveflow (wrapping) when
1342 multiplied. When ARGS[0] is null the function does nothing. ARGS[1]
1343 may be null for functions like malloc, and non-null for those like
1344 calloc that are decorated with a two-argument attribute alloc_size. */
1347 maybe_warn_alloc_args_overflow (tree fn
, tree exp
, tree args
[2], int idx
[2])
1349 /* The range each of the (up to) two arguments is known to be in. */
1350 tree argrange
[2][2] = { { NULL_TREE
, NULL_TREE
}, { NULL_TREE
, NULL_TREE
} };
1352 /* Maximum object size set by -Walloc-size-larger-than= or SIZE_MAX / 2. */
1353 tree maxobjsize
= alloc_max_size ();
1355 location_t loc
= EXPR_LOCATION (exp
);
1357 bool warned
= false;
1359 /* Validate each argument individually. */
1360 for (unsigned i
= 0; i
!= 2 && args
[i
]; ++i
)
1362 if (TREE_CODE (args
[i
]) == INTEGER_CST
)
1364 argrange
[i
][0] = args
[i
];
1365 argrange
[i
][1] = args
[i
];
1367 if (tree_int_cst_lt (args
[i
], integer_zero_node
))
1369 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1370 "%Kargument %i value %qE is negative",
1371 exp
, idx
[i
] + 1, args
[i
]);
1373 else if (integer_zerop (args
[i
]))
1375 /* Avoid issuing -Walloc-zero for allocation functions other
1376 than __builtin_alloca that are declared with attribute
1377 returns_nonnull because there's no portability risk. This
1378 avoids warning for such calls to libiberty's xmalloc and
1380 Also avoid issuing the warning for calls to function named
1382 if ((DECL_FUNCTION_CODE (fn
) == BUILT_IN_ALLOCA
1383 && IDENTIFIER_LENGTH (DECL_NAME (fn
)) != 6)
1384 || (DECL_FUNCTION_CODE (fn
) != BUILT_IN_ALLOCA
1385 && !lookup_attribute ("returns_nonnull",
1386 TYPE_ATTRIBUTES (TREE_TYPE (fn
)))))
1387 warned
= warning_at (loc
, OPT_Walloc_zero
,
1388 "%Kargument %i value is zero",
1391 else if (tree_int_cst_lt (maxobjsize
, args
[i
]))
1393 /* G++ emits calls to ::operator new[](SIZE_MAX) in C++98
1394 mode and with -fno-exceptions as a way to indicate array
1395 size overflow. There's no good way to detect C++98 here
1396 so avoid diagnosing these calls for all C++ modes. */
1400 && DECL_IS_OPERATOR_NEW (fn
)
1401 && integer_all_onesp (args
[i
]))
1404 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1405 "%Kargument %i value %qE exceeds "
1406 "maximum object size %E",
1407 exp
, idx
[i
] + 1, args
[i
], maxobjsize
);
1410 else if (TREE_CODE (args
[i
]) == SSA_NAME
1411 && get_size_range (args
[i
], argrange
[i
]))
1413 /* Verify that the argument's range is not negative (including
1414 upper bound of zero). */
1415 if (tree_int_cst_lt (argrange
[i
][0], integer_zero_node
)
1416 && tree_int_cst_le (argrange
[i
][1], integer_zero_node
))
1418 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1419 "%Kargument %i range [%E, %E] is negative",
1421 argrange
[i
][0], argrange
[i
][1]);
1423 else if (tree_int_cst_lt (maxobjsize
, argrange
[i
][0]))
1425 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1426 "%Kargument %i range [%E, %E] exceeds "
1427 "maximum object size %E",
1429 argrange
[i
][0], argrange
[i
][1],
1438 /* For a two-argument alloc_size, validate the product of the two
1439 arguments if both of their values or ranges are known. */
1440 if (!warned
&& tree_fits_uhwi_p (argrange
[0][0])
1441 && argrange
[1][0] && tree_fits_uhwi_p (argrange
[1][0])
1442 && !integer_onep (argrange
[0][0])
1443 && !integer_onep (argrange
[1][0]))
1445 /* Check for overflow in the product of a function decorated with
1446 attribute alloc_size (X, Y). */
1447 unsigned szprec
= TYPE_PRECISION (size_type_node
);
1448 wide_int x
= wi::to_wide (argrange
[0][0], szprec
);
1449 wide_int y
= wi::to_wide (argrange
[1][0], szprec
);
1451 wi::overflow_type vflow
;
1452 wide_int prod
= wi::umul (x
, y
, &vflow
);
1455 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1456 "%Kproduct %<%E * %E%> of arguments %i and %i "
1457 "exceeds %<SIZE_MAX%>",
1458 exp
, argrange
[0][0], argrange
[1][0],
1459 idx
[0] + 1, idx
[1] + 1);
1460 else if (wi::ltu_p (wi::to_wide (maxobjsize
, szprec
), prod
))
1461 warned
= warning_at (loc
, OPT_Walloc_size_larger_than_
,
1462 "%Kproduct %<%E * %E%> of arguments %i and %i "
1463 "exceeds maximum object size %E",
1464 exp
, argrange
[0][0], argrange
[1][0],
1465 idx
[0] + 1, idx
[1] + 1,
1470 /* Print the full range of each of the two arguments to make
1471 it clear when it is, in fact, in a range and not constant. */
1472 if (argrange
[0][0] != argrange
[0][1])
1473 inform (loc
, "argument %i in the range [%E, %E]",
1474 idx
[0] + 1, argrange
[0][0], argrange
[0][1]);
1475 if (argrange
[1][0] != argrange
[1][1])
1476 inform (loc
, "argument %i in the range [%E, %E]",
1477 idx
[1] + 1, argrange
[1][0], argrange
[1][1]);
1483 location_t fnloc
= DECL_SOURCE_LOCATION (fn
);
1485 if (DECL_IS_BUILTIN (fn
))
1487 "in a call to built-in allocation function %qD", fn
);
1490 "in a call to allocation function %qD declared here", fn
);
1494 /* If EXPR refers to a character array or pointer declared attribute
1495 nonstring return a decl for that array or pointer and set *REF to
1496 the referenced enclosing object or pointer. Otherwise returns
1500 get_attr_nonstring_decl (tree expr
, tree
*ref
)
1503 if (TREE_CODE (decl
) == SSA_NAME
)
1505 gimple
*def
= SSA_NAME_DEF_STMT (decl
);
1507 if (is_gimple_assign (def
))
1509 tree_code code
= gimple_assign_rhs_code (def
);
1510 if (code
== ADDR_EXPR
1511 || code
== COMPONENT_REF
1512 || code
== VAR_DECL
)
1513 decl
= gimple_assign_rhs1 (def
);
1515 else if (tree var
= SSA_NAME_VAR (decl
))
1519 if (TREE_CODE (decl
) == ADDR_EXPR
)
1520 decl
= TREE_OPERAND (decl
, 0);
1525 if (TREE_CODE (decl
) == ARRAY_REF
)
1526 decl
= TREE_OPERAND (decl
, 0);
1527 else if (TREE_CODE (decl
) == COMPONENT_REF
)
1528 decl
= TREE_OPERAND (decl
, 1);
1529 else if (TREE_CODE (decl
) == MEM_REF
)
1530 return get_attr_nonstring_decl (TREE_OPERAND (decl
, 0), ref
);
1533 && lookup_attribute ("nonstring", DECL_ATTRIBUTES (decl
)))
1539 /* Warn about passing a non-string array/pointer to a function that
1540 expects a nul-terminated string argument. */
1543 maybe_warn_nonstring_arg (tree fndecl
, tree exp
)
1545 if (!fndecl
|| DECL_BUILT_IN_CLASS (fndecl
) != BUILT_IN_NORMAL
)
1548 if (TREE_NO_WARNING (exp
))
1551 unsigned nargs
= call_expr_nargs (exp
);
1553 /* The bound argument to a bounded string function like strncpy. */
1554 tree bound
= NULL_TREE
;
1556 /* The range of lengths of a string argument to one of the comparison
1557 functions. If the length is less than the bound it is used instead. */
1558 tree lenrng
[2] = { NULL_TREE
, NULL_TREE
};
1560 /* It's safe to call "bounded" string functions with a non-string
1561 argument since the functions provide an explicit bound for this
1562 purpose. The exception is strncat where the bound may refer to
1563 either the destination or the source. */
1564 int fncode
= DECL_FUNCTION_CODE (fndecl
);
1567 case BUILT_IN_STRCMP
:
1568 case BUILT_IN_STRNCMP
:
1569 case BUILT_IN_STRNCASECMP
:
1571 /* For these, if one argument refers to one or more of a set
1572 of string constants or arrays of known size, determine
1573 the range of their known or possible lengths and use it
1574 conservatively as the bound for the unbounded function,
1575 and to adjust the range of the bound of the bounded ones. */
1576 for (unsigned argno
= 0; argno
< nargs
&& !*lenrng
; argno
++)
1578 tree arg
= CALL_EXPR_ARG (exp
, argno
);
1579 if (!get_attr_nonstring_decl (arg
))
1580 get_range_strlen (arg
, lenrng
);
1585 case BUILT_IN_STRNCAT
:
1586 case BUILT_IN_STPNCPY
:
1587 case BUILT_IN_STRNCPY
:
1589 bound
= CALL_EXPR_ARG (exp
, 2);
1592 case BUILT_IN_STRNDUP
:
1594 bound
= CALL_EXPR_ARG (exp
, 1);
1597 case BUILT_IN_STRNLEN
:
1599 tree arg
= CALL_EXPR_ARG (exp
, 0);
1600 if (!get_attr_nonstring_decl (arg
))
1601 get_range_strlen (arg
, lenrng
);
1604 bound
= CALL_EXPR_ARG (exp
, 1);
1612 /* Determine the range of the bound argument (if specified). */
1613 tree bndrng
[2] = { NULL_TREE
, NULL_TREE
};
1617 get_size_range (bound
, bndrng
);
1620 location_t loc
= EXPR_LOCATION (exp
);
1624 /* Diagnose excessive bound prior the adjustment below and
1625 regardless of attribute nonstring. */
1626 tree maxobjsize
= max_object_size ();
1627 if (tree_int_cst_lt (maxobjsize
, bndrng
[0]))
1629 if (tree_int_cst_equal (bndrng
[0], bndrng
[1]))
1630 warning_at (loc
, OPT_Wstringop_overflow_
,
1631 "%K%qD specified bound %E "
1632 "exceeds maximum object size %E",
1633 exp
, fndecl
, bndrng
[0], maxobjsize
);
1635 warning_at (loc
, OPT_Wstringop_overflow_
,
1636 "%K%qD specified bound [%E, %E] "
1637 "exceeds maximum object size %E",
1638 exp
, fndecl
, bndrng
[0], bndrng
[1], maxobjsize
);
1645 /* Add one for the nul. */
1646 lenrng
[0] = const_binop (PLUS_EXPR
, TREE_TYPE (lenrng
[0]),
1647 lenrng
[0], size_one_node
);
1648 lenrng
[1] = const_binop (PLUS_EXPR
, TREE_TYPE (lenrng
[1]),
1649 lenrng
[1], size_one_node
);
1653 /* Conservatively use the upper bound of the lengths for
1654 both the lower and the upper bound of the operation. */
1655 bndrng
[0] = lenrng
[1];
1656 bndrng
[1] = lenrng
[1];
1657 bound
= void_type_node
;
1661 /* Replace the bound on the operation with the upper bound
1662 of the length of the string if the latter is smaller. */
1663 if (tree_int_cst_lt (lenrng
[1], bndrng
[0]))
1664 bndrng
[0] = lenrng
[1];
1665 else if (tree_int_cst_lt (lenrng
[1], bndrng
[1]))
1666 bndrng
[1] = lenrng
[1];
1670 /* Iterate over the built-in function's formal arguments and check
1671 each const char* against the actual argument. If the actual
1672 argument is declared attribute non-string issue a warning unless
1673 the argument's maximum length is bounded. */
1674 function_args_iterator it
;
1675 function_args_iter_init (&it
, TREE_TYPE (fndecl
));
1677 for (unsigned argno
= 0; ; ++argno
, function_args_iter_next (&it
))
1679 /* Avoid iterating past the declared argument in a call
1680 to function declared without a prototype. */
1684 tree argtype
= function_args_iter_cond (&it
);
1688 if (TREE_CODE (argtype
) != POINTER_TYPE
)
1691 argtype
= TREE_TYPE (argtype
);
1693 if (TREE_CODE (argtype
) != INTEGER_TYPE
1694 || !TYPE_READONLY (argtype
))
1697 argtype
= TYPE_MAIN_VARIANT (argtype
);
1698 if (argtype
!= char_type_node
)
1701 tree callarg
= CALL_EXPR_ARG (exp
, argno
);
1702 if (TREE_CODE (callarg
) == ADDR_EXPR
)
1703 callarg
= TREE_OPERAND (callarg
, 0);
1705 /* See if the destination is declared with attribute "nonstring". */
1706 tree decl
= get_attr_nonstring_decl (callarg
);
1710 /* The maximum number of array elements accessed. */
1711 offset_int wibnd
= 0;
1713 if (argno
&& fncode
== BUILT_IN_STRNCAT
)
1715 /* See if the bound in strncat is derived from the length
1716 of the strlen of the destination (as it's expected to be).
1717 If so, reset BOUND and FNCODE to trigger a warning. */
1718 tree dstarg
= CALL_EXPR_ARG (exp
, 0);
1719 if (is_strlen_related_p (dstarg
, bound
))
1721 /* The bound applies to the destination, not to the source,
1722 so reset these to trigger a warning without mentioning
1728 /* Use the upper bound of the range for strncat. */
1729 wibnd
= wi::to_offset (bndrng
[1]);
1732 /* Use the lower bound of the range for functions other than
1734 wibnd
= wi::to_offset (bndrng
[0]);
1736 /* Determine the size of the argument array if it is one. */
1737 offset_int asize
= wibnd
;
1738 bool known_size
= false;
1739 tree type
= TREE_TYPE (decl
);
1741 /* Determine the array size. For arrays of unknown bound and
1742 pointers reset BOUND to trigger the appropriate warning. */
1743 if (TREE_CODE (type
) == ARRAY_TYPE
)
1745 if (tree arrbnd
= TYPE_DOMAIN (type
))
1747 if ((arrbnd
= TYPE_MAX_VALUE (arrbnd
)))
1749 asize
= wi::to_offset (arrbnd
) + 1;
1753 else if (bound
== void_type_node
)
1756 else if (bound
== void_type_node
)
1759 /* In a call to strncat with a bound in a range whose lower but
1760 not upper bound is less than the array size, reset ASIZE to
1761 be the same as the bound and the other variable to trigger
1762 the apprpriate warning below. */
1763 if (fncode
== BUILT_IN_STRNCAT
1764 && bndrng
[0] != bndrng
[1]
1765 && wi::ltu_p (wi::to_offset (bndrng
[0]), asize
)
1767 || wi::ltu_p (asize
, wibnd
)))
1774 bool warned
= false;
1776 auto_diagnostic_group d
;
1777 if (wi::ltu_p (asize
, wibnd
))
1779 if (bndrng
[0] == bndrng
[1])
1780 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1781 "%qD argument %i declared attribute "
1782 "%<nonstring%> is smaller than the specified "
1784 fndecl
, argno
+ 1, wibnd
.to_uhwi ());
1785 else if (wi::ltu_p (asize
, wi::to_offset (bndrng
[0])))
1786 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1787 "%qD argument %i declared attribute "
1788 "%<nonstring%> is smaller than "
1789 "the specified bound [%E, %E]",
1790 fndecl
, argno
+ 1, bndrng
[0], bndrng
[1]);
1792 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1793 "%qD argument %i declared attribute "
1794 "%<nonstring%> may be smaller than "
1795 "the specified bound [%E, %E]",
1796 fndecl
, argno
+ 1, bndrng
[0], bndrng
[1]);
1798 else if (fncode
== BUILT_IN_STRNCAT
)
1799 ; /* Avoid warning for calls to strncat() when the bound
1800 is equal to the size of the non-string argument. */
1802 warned
= warning_at (loc
, OPT_Wstringop_overflow_
,
1803 "%qD argument %i declared attribute %<nonstring%>",
1807 inform (DECL_SOURCE_LOCATION (decl
),
1808 "argument %qD declared here", decl
);
1812 /* Issue an error if CALL_EXPR was flagged as requiring
1813 tall-call optimization. */
1816 maybe_complain_about_tail_call (tree call_expr
, const char *reason
)
1818 gcc_assert (TREE_CODE (call_expr
) == CALL_EXPR
);
1819 if (!CALL_EXPR_MUST_TAIL_CALL (call_expr
))
1822 error_at (EXPR_LOCATION (call_expr
), "cannot tail-call: %s", reason
);
1825 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1828 NUM_ACTUALS is the total number of parameters.
1830 N_NAMED_ARGS is the total number of named arguments.
1832 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1835 FNDECL is the tree code for the target of this call (if known)
1837 ARGS_SO_FAR holds state needed by the target to know where to place
1840 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1841 for arguments which are passed in registers.
1843 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1844 and may be modified by this routine.
1846 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1847 flags which may be modified by this routine.
1849 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1850 that requires allocation of stack space.
1852 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1853 the thunked-to function. */
1856 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
1857 struct arg_data
*args
,
1858 struct args_size
*args_size
,
1859 int n_named_args ATTRIBUTE_UNUSED
,
1860 tree exp
, tree struct_value_addr_value
,
1861 tree fndecl
, tree fntype
,
1862 cumulative_args_t args_so_far
,
1863 int reg_parm_stack_space
,
1864 rtx
*old_stack_level
,
1865 poly_int64_pod
*old_pending_adj
,
1866 int *must_preallocate
, int *ecf_flags
,
1867 bool *may_tailcall
, bool call_from_thunk_p
)
1869 CUMULATIVE_ARGS
*args_so_far_pnt
= get_cumulative_args (args_so_far
);
1870 location_t loc
= EXPR_LOCATION (exp
);
1872 /* Count arg position in order args appear. */
1877 args_size
->constant
= 0;
1880 bitmap_obstack_initialize (NULL
);
1882 /* In this loop, we consider args in the order they are written.
1883 We fill up ARGS from the back. */
1885 i
= num_actuals
- 1;
1888 call_expr_arg_iterator iter
;
1890 bitmap slots
= NULL
;
1892 if (struct_value_addr_value
)
1894 args
[j
].tree_value
= struct_value_addr_value
;
1898 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
1900 tree argtype
= TREE_TYPE (arg
);
1902 if (targetm
.calls
.split_complex_arg
1904 && TREE_CODE (argtype
) == COMPLEX_TYPE
1905 && targetm
.calls
.split_complex_arg (argtype
))
1907 tree subtype
= TREE_TYPE (argtype
);
1908 args
[j
].tree_value
= build1 (REALPART_EXPR
, subtype
, arg
);
1910 args
[j
].tree_value
= build1 (IMAGPART_EXPR
, subtype
, arg
);
1913 args
[j
].tree_value
= arg
;
1919 BITMAP_FREE (slots
);
1922 bitmap_obstack_release (NULL
);
1924 /* Extract attribute alloc_size and if set, store the indices of
1925 the corresponding arguments in ALLOC_IDX, and then the actual
1926 argument(s) at those indices in ALLOC_ARGS. */
1927 int alloc_idx
[2] = { -1, -1 };
1929 = (fndecl
? lookup_attribute ("alloc_size",
1930 TYPE_ATTRIBUTES (TREE_TYPE (fndecl
)))
1933 tree args
= TREE_VALUE (alloc_size
);
1934 alloc_idx
[0] = TREE_INT_CST_LOW (TREE_VALUE (args
)) - 1;
1935 if (TREE_CHAIN (args
))
1936 alloc_idx
[1] = TREE_INT_CST_LOW (TREE_VALUE (TREE_CHAIN (args
))) - 1;
1939 /* Array for up to the two attribute alloc_size arguments. */
1940 tree alloc_args
[] = { NULL_TREE
, NULL_TREE
};
1942 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1943 for (argpos
= 0; argpos
< num_actuals
; i
--, argpos
++)
1945 tree type
= TREE_TYPE (args
[i
].tree_value
);
1949 /* Replace erroneous argument with constant zero. */
1950 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1951 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1953 /* If TYPE is a transparent union or record, pass things the way
1954 we would pass the first field of the union or record. We have
1955 already verified that the modes are the same. */
1956 if ((TREE_CODE (type
) == UNION_TYPE
|| TREE_CODE (type
) == RECORD_TYPE
)
1957 && TYPE_TRANSPARENT_AGGR (type
))
1958 type
= TREE_TYPE (first_field (type
));
1960 /* Decide where to pass this arg.
1962 args[i].reg is nonzero if all or part is passed in registers.
1964 args[i].partial is nonzero if part but not all is passed in registers,
1965 and the exact value says how many bytes are passed in registers.
1967 args[i].pass_on_stack is nonzero if the argument must at least be
1968 computed on the stack. It may then be loaded back into registers
1969 if args[i].reg is nonzero.
1971 These decisions are driven by the FUNCTION_... macros and must agree
1972 with those made by function.c. */
1974 /* See if this argument should be passed by invisible reference. */
1975 if (pass_by_reference (args_so_far_pnt
, TYPE_MODE (type
),
1976 type
, argpos
< n_named_args
))
1979 tree base
= NULL_TREE
;
1982 = reference_callee_copied (args_so_far_pnt
, TYPE_MODE (type
),
1983 type
, argpos
< n_named_args
);
1985 /* If we're compiling a thunk, pass through invisible references
1986 instead of making a copy. */
1987 if (call_from_thunk_p
1989 && !TREE_ADDRESSABLE (type
)
1990 && (base
= get_base_address (args
[i
].tree_value
))
1991 && TREE_CODE (base
) != SSA_NAME
1992 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
)))))
1994 /* We may have turned the parameter value into an SSA name.
1995 Go back to the original parameter so we can take the
1997 if (TREE_CODE (args
[i
].tree_value
) == SSA_NAME
)
1999 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args
[i
].tree_value
));
2000 args
[i
].tree_value
= SSA_NAME_VAR (args
[i
].tree_value
);
2001 gcc_assert (TREE_CODE (args
[i
].tree_value
) == PARM_DECL
);
2003 /* Argument setup code may have copied the value to register. We
2004 revert that optimization now because the tail call code must
2005 use the original location. */
2006 if (TREE_CODE (args
[i
].tree_value
) == PARM_DECL
2007 && !MEM_P (DECL_RTL (args
[i
].tree_value
))
2008 && DECL_INCOMING_RTL (args
[i
].tree_value
)
2009 && MEM_P (DECL_INCOMING_RTL (args
[i
].tree_value
)))
2010 set_decl_rtl (args
[i
].tree_value
,
2011 DECL_INCOMING_RTL (args
[i
].tree_value
));
2013 mark_addressable (args
[i
].tree_value
);
2015 /* We can't use sibcalls if a callee-copied argument is
2016 stored in the current function's frame. */
2017 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
2019 *may_tailcall
= false;
2020 maybe_complain_about_tail_call (exp
,
2021 "a callee-copied argument is"
2022 " stored in the current"
2023 " function's frame");
2026 args
[i
].tree_value
= build_fold_addr_expr_loc (loc
,
2027 args
[i
].tree_value
);
2028 type
= TREE_TYPE (args
[i
].tree_value
);
2030 if (*ecf_flags
& ECF_CONST
)
2031 *ecf_flags
&= ~(ECF_CONST
| ECF_LOOPING_CONST_OR_PURE
);
2035 /* We make a copy of the object and pass the address to the
2036 function being called. */
2039 if (!COMPLETE_TYPE_P (type
)
2040 || TREE_CODE (TYPE_SIZE_UNIT (type
)) != INTEGER_CST
2041 || (flag_stack_check
== GENERIC_STACK_CHECK
2042 && compare_tree_int (TYPE_SIZE_UNIT (type
),
2043 STACK_CHECK_MAX_VAR_SIZE
) > 0))
2045 /* This is a variable-sized object. Make space on the stack
2047 rtx size_rtx
= expr_size (args
[i
].tree_value
);
2049 if (*old_stack_level
== 0)
2051 emit_stack_save (SAVE_BLOCK
, old_stack_level
);
2052 *old_pending_adj
= pending_stack_adjust
;
2053 pending_stack_adjust
= 0;
2056 /* We can pass TRUE as the 4th argument because we just
2057 saved the stack pointer and will restore it right after
2059 copy
= allocate_dynamic_stack_space (size_rtx
,
2062 max_int_size_in_bytes
2065 copy
= gen_rtx_MEM (BLKmode
, copy
);
2066 set_mem_attributes (copy
, type
, 1);
2069 copy
= assign_temp (type
, 1, 0);
2071 store_expr (args
[i
].tree_value
, copy
, 0, false, false);
2073 /* Just change the const function to pure and then let
2074 the next test clear the pure based on
2076 if (*ecf_flags
& ECF_CONST
)
2078 *ecf_flags
&= ~ECF_CONST
;
2079 *ecf_flags
|= ECF_PURE
;
2082 if (!callee_copies
&& *ecf_flags
& ECF_PURE
)
2083 *ecf_flags
&= ~(ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
2086 = build_fold_addr_expr_loc (loc
, make_tree (type
, copy
));
2087 type
= TREE_TYPE (args
[i
].tree_value
);
2088 *may_tailcall
= false;
2089 maybe_complain_about_tail_call (exp
,
2090 "argument must be passed"
2095 unsignedp
= TYPE_UNSIGNED (type
);
2096 mode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
2097 fndecl
? TREE_TYPE (fndecl
) : fntype
, 0);
2099 args
[i
].unsignedp
= unsignedp
;
2100 args
[i
].mode
= mode
;
2102 targetm
.calls
.warn_parameter_passing_abi (args_so_far
, type
);
2104 args
[i
].reg
= targetm
.calls
.function_arg (args_so_far
, mode
, type
,
2105 argpos
< n_named_args
);
2107 if (args
[i
].reg
&& CONST_INT_P (args
[i
].reg
))
2109 args
[i
].special_slot
= args
[i
].reg
;
2113 /* If this is a sibling call and the machine has register windows, the
2114 register window has to be unwinded before calling the routine, so
2115 arguments have to go into the incoming registers. */
2116 if (targetm
.calls
.function_incoming_arg
!= targetm
.calls
.function_arg
)
2117 args
[i
].tail_call_reg
2118 = targetm
.calls
.function_incoming_arg (args_so_far
, mode
, type
,
2119 argpos
< n_named_args
);
2121 args
[i
].tail_call_reg
= args
[i
].reg
;
2125 = targetm
.calls
.arg_partial_bytes (args_so_far
, mode
, type
,
2126 argpos
< n_named_args
);
2128 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (mode
, type
);
2130 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
2131 it means that we are to pass this arg in the register(s) designated
2132 by the PARALLEL, but also to pass it in the stack. */
2133 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
2134 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
2135 args
[i
].pass_on_stack
= 1;
2137 /* If this is an addressable type, we must preallocate the stack
2138 since we must evaluate the object into its final location.
2140 If this is to be passed in both registers and the stack, it is simpler
2142 if (TREE_ADDRESSABLE (type
)
2143 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
2144 *must_preallocate
= 1;
2146 /* Compute the stack-size of this argument. */
2147 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
2148 || reg_parm_stack_space
> 0
2149 || args
[i
].pass_on_stack
)
2150 locate_and_pad_parm (mode
, type
,
2151 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2156 reg_parm_stack_space
,
2157 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
2158 fndecl
, args_size
, &args
[i
].locate
);
2159 #ifdef BLOCK_REG_PADDING
2161 /* The argument is passed entirely in registers. See at which
2162 end it should be padded. */
2163 args
[i
].locate
.where_pad
=
2164 BLOCK_REG_PADDING (mode
, type
,
2165 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
2168 /* Update ARGS_SIZE, the total stack space for args so far. */
2170 args_size
->constant
+= args
[i
].locate
.size
.constant
;
2171 if (args
[i
].locate
.size
.var
)
2172 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
2174 /* Increment ARGS_SO_FAR, which has info about which arg-registers
2175 have been used, etc. */
2177 targetm
.calls
.function_arg_advance (args_so_far
, TYPE_MODE (type
),
2178 type
, argpos
< n_named_args
);
2180 /* Store argument values for functions decorated with attribute
2182 if (argpos
== alloc_idx
[0])
2183 alloc_args
[0] = args
[i
].tree_value
;
2184 else if (argpos
== alloc_idx
[1])
2185 alloc_args
[1] = args
[i
].tree_value
;
2190 /* Check the arguments of functions decorated with attribute
2192 maybe_warn_alloc_args_overflow (fndecl
, exp
, alloc_args
, alloc_idx
);
2195 /* Detect passing non-string arguments to functions expecting
2196 nul-terminated strings. */
2197 maybe_warn_nonstring_arg (fndecl
, exp
);
2200 /* Update ARGS_SIZE to contain the total size for the argument block.
2201 Return the original constant component of the argument block's size.
2203 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
2204 for arguments passed in registers. */
2207 compute_argument_block_size (int reg_parm_stack_space
,
2208 struct args_size
*args_size
,
2209 tree fndecl ATTRIBUTE_UNUSED
,
2210 tree fntype ATTRIBUTE_UNUSED
,
2211 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
2213 poly_int64 unadjusted_args_size
= args_size
->constant
;
2215 /* For accumulate outgoing args mode we don't need to align, since the frame
2216 will be already aligned. Align to STACK_BOUNDARY in order to prevent
2217 backends from generating misaligned frame sizes. */
2218 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
2219 preferred_stack_boundary
= STACK_BOUNDARY
;
2221 /* Compute the actual size of the argument block required. The variable
2222 and constant sizes must be combined, the size may have to be rounded,
2223 and there may be a minimum required size. */
2227 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
2228 args_size
->constant
= 0;
2230 preferred_stack_boundary
/= BITS_PER_UNIT
;
2231 if (preferred_stack_boundary
> 1)
2233 /* We don't handle this case yet. To handle it correctly we have
2234 to add the delta, round and subtract the delta.
2235 Currently no machine description requires this support. */
2236 gcc_assert (multiple_p (stack_pointer_delta
,
2237 preferred_stack_boundary
));
2238 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
2241 if (reg_parm_stack_space
> 0)
2244 = size_binop (MAX_EXPR
, args_size
->var
,
2245 ssize_int (reg_parm_stack_space
));
2247 /* The area corresponding to register parameters is not to count in
2248 the size of the block we need. So make the adjustment. */
2249 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2251 = size_binop (MINUS_EXPR
, args_size
->var
,
2252 ssize_int (reg_parm_stack_space
));
2257 preferred_stack_boundary
/= BITS_PER_UNIT
;
2258 if (preferred_stack_boundary
< 1)
2259 preferred_stack_boundary
= 1;
2260 args_size
->constant
= (aligned_upper_bound (args_size
->constant
2261 + stack_pointer_delta
,
2262 preferred_stack_boundary
)
2263 - stack_pointer_delta
);
2265 args_size
->constant
= upper_bound (args_size
->constant
,
2266 reg_parm_stack_space
);
2268 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2269 args_size
->constant
-= reg_parm_stack_space
;
2271 return unadjusted_args_size
;
2274 /* Precompute parameters as needed for a function call.
2276 FLAGS is mask of ECF_* constants.
2278 NUM_ACTUALS is the number of arguments.
2280 ARGS is an array containing information for each argument; this
2281 routine fills in the INITIAL_VALUE and VALUE fields for each
2282 precomputed argument. */
2285 precompute_arguments (int num_actuals
, struct arg_data
*args
)
2289 /* If this is a libcall, then precompute all arguments so that we do not
2290 get extraneous instructions emitted as part of the libcall sequence. */
2292 /* If we preallocated the stack space, and some arguments must be passed
2293 on the stack, then we must precompute any parameter which contains a
2294 function call which will store arguments on the stack.
2295 Otherwise, evaluating the parameter may clobber previous parameters
2296 which have already been stored into the stack. (we have code to avoid
2297 such case by saving the outgoing stack arguments, but it results in
2299 if (!ACCUMULATE_OUTGOING_ARGS
)
2302 for (i
= 0; i
< num_actuals
; i
++)
2307 if (TREE_CODE (args
[i
].tree_value
) != CALL_EXPR
)
2310 /* If this is an addressable type, we cannot pre-evaluate it. */
2311 type
= TREE_TYPE (args
[i
].tree_value
);
2312 gcc_assert (!TREE_ADDRESSABLE (type
));
2314 args
[i
].initial_value
= args
[i
].value
2315 = expand_normal (args
[i
].tree_value
);
2317 mode
= TYPE_MODE (type
);
2318 if (mode
!= args
[i
].mode
)
2320 int unsignedp
= args
[i
].unsignedp
;
2322 = convert_modes (args
[i
].mode
, mode
,
2323 args
[i
].value
, args
[i
].unsignedp
);
2325 /* CSE will replace this only if it contains args[i].value
2326 pseudo, so convert it down to the declared mode using
2328 if (REG_P (args
[i
].value
)
2329 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
2330 && promote_mode (type
, mode
, &unsignedp
) != args
[i
].mode
)
2332 args
[i
].initial_value
2333 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
2334 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
2335 SUBREG_PROMOTED_SET (args
[i
].initial_value
, args
[i
].unsignedp
);
2341 /* Given the current state of MUST_PREALLOCATE and information about
2342 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
2343 compute and return the final value for MUST_PREALLOCATE. */
2346 finalize_must_preallocate (int must_preallocate
, int num_actuals
,
2347 struct arg_data
*args
, struct args_size
*args_size
)
2349 /* See if we have or want to preallocate stack space.
2351 If we would have to push a partially-in-regs parm
2352 before other stack parms, preallocate stack space instead.
2354 If the size of some parm is not a multiple of the required stack
2355 alignment, we must preallocate.
2357 If the total size of arguments that would otherwise create a copy in
2358 a temporary (such as a CALL) is more than half the total argument list
2359 size, preallocation is faster.
2361 Another reason to preallocate is if we have a machine (like the m88k)
2362 where stack alignment is required to be maintained between every
2363 pair of insns, not just when the call is made. However, we assume here
2364 that such machines either do not have push insns (and hence preallocation
2365 would occur anyway) or the problem is taken care of with
2368 if (! must_preallocate
)
2370 int partial_seen
= 0;
2371 poly_int64 copy_to_evaluate_size
= 0;
2374 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
2376 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
2378 else if (partial_seen
&& args
[i
].reg
== 0)
2379 must_preallocate
= 1;
2381 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
2382 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
2383 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
2384 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
2385 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
2386 copy_to_evaluate_size
2387 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
2390 if (maybe_ne (args_size
->constant
, 0)
2391 && maybe_ge (copy_to_evaluate_size
* 2, args_size
->constant
))
2392 must_preallocate
= 1;
2394 return must_preallocate
;
2397 /* If we preallocated stack space, compute the address of each argument
2398 and store it into the ARGS array.
2400 We need not ensure it is a valid memory address here; it will be
2401 validized when it is used.
2403 ARGBLOCK is an rtx for the address of the outgoing arguments. */
2406 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
2410 rtx arg_reg
= argblock
;
2412 poly_int64 arg_offset
= 0;
2414 if (GET_CODE (argblock
) == PLUS
)
2416 arg_reg
= XEXP (argblock
, 0);
2417 arg_offset
= rtx_to_poly_int64 (XEXP (argblock
, 1));
2420 for (i
= 0; i
< num_actuals
; i
++)
2422 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
2423 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
2425 unsigned int align
, boundary
;
2426 poly_uint64 units_on_stack
= 0;
2427 machine_mode partial_mode
= VOIDmode
;
2429 /* Skip this parm if it will not be passed on the stack. */
2430 if (! args
[i
].pass_on_stack
2432 && args
[i
].partial
== 0)
2435 if (TYPE_EMPTY_P (TREE_TYPE (args
[i
].tree_value
)))
2438 addr
= simplify_gen_binary (PLUS
, Pmode
, arg_reg
, offset
);
2439 addr
= plus_constant (Pmode
, addr
, arg_offset
);
2441 if (args
[i
].partial
!= 0)
2443 /* Only part of the parameter is being passed on the stack.
2444 Generate a simple memory reference of the correct size. */
2445 units_on_stack
= args
[i
].locate
.size
.constant
;
2446 poly_uint64 bits_on_stack
= units_on_stack
* BITS_PER_UNIT
;
2447 partial_mode
= int_mode_for_size (bits_on_stack
, 1).else_blk ();
2448 args
[i
].stack
= gen_rtx_MEM (partial_mode
, addr
);
2449 set_mem_size (args
[i
].stack
, units_on_stack
);
2453 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
2454 set_mem_attributes (args
[i
].stack
,
2455 TREE_TYPE (args
[i
].tree_value
), 1);
2457 align
= BITS_PER_UNIT
;
2458 boundary
= args
[i
].locate
.boundary
;
2459 poly_int64 offset_val
;
2460 if (args
[i
].locate
.where_pad
!= PAD_DOWNWARD
)
2462 else if (poly_int_rtx_p (offset
, &offset_val
))
2464 align
= least_bit_hwi (boundary
);
2465 unsigned int offset_align
2466 = known_alignment (offset_val
) * BITS_PER_UNIT
;
2467 if (offset_align
!= 0)
2468 align
= MIN (align
, offset_align
);
2470 set_mem_align (args
[i
].stack
, align
);
2472 addr
= simplify_gen_binary (PLUS
, Pmode
, arg_reg
, slot_offset
);
2473 addr
= plus_constant (Pmode
, addr
, arg_offset
);
2475 if (args
[i
].partial
!= 0)
2477 /* Only part of the parameter is being passed on the stack.
2478 Generate a simple memory reference of the correct size.
2480 args
[i
].stack_slot
= gen_rtx_MEM (partial_mode
, addr
);
2481 set_mem_size (args
[i
].stack_slot
, units_on_stack
);
2485 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
2486 set_mem_attributes (args
[i
].stack_slot
,
2487 TREE_TYPE (args
[i
].tree_value
), 1);
2489 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
2491 /* Function incoming arguments may overlap with sibling call
2492 outgoing arguments and we cannot allow reordering of reads
2493 from function arguments with stores to outgoing arguments
2494 of sibling calls. */
2495 set_mem_alias_set (args
[i
].stack
, 0);
2496 set_mem_alias_set (args
[i
].stack_slot
, 0);
2501 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
2502 in a call instruction.
2504 FNDECL is the tree node for the target function. For an indirect call
2505 FNDECL will be NULL_TREE.
2507 ADDR is the operand 0 of CALL_EXPR for this call. */
2510 rtx_for_function_call (tree fndecl
, tree addr
)
2514 /* Get the function to call, in the form of RTL. */
2517 if (!TREE_USED (fndecl
) && fndecl
!= current_function_decl
)
2518 TREE_USED (fndecl
) = 1;
2520 /* Get a SYMBOL_REF rtx for the function address. */
2521 funexp
= XEXP (DECL_RTL (fndecl
), 0);
2524 /* Generate an rtx (probably a pseudo-register) for the address. */
2527 funexp
= expand_normal (addr
);
2528 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
2533 /* Return the static chain for this function, if any. */
2536 rtx_for_static_chain (const_tree fndecl_or_type
, bool incoming_p
)
2538 if (DECL_P (fndecl_or_type
) && !DECL_STATIC_CHAIN (fndecl_or_type
))
2541 return targetm
.calls
.static_chain (fndecl_or_type
, incoming_p
);
2544 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
2547 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
2548 or NULL_RTX if none has been scanned yet. */
2549 rtx_insn
*scan_start
;
2550 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
2551 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
2552 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
2553 with fixed offset, or PC if this is with variable or unknown offset. */
2555 } internal_arg_pointer_exp_state
;
2557 static rtx
internal_arg_pointer_based_exp (const_rtx
, bool);
2559 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
2560 the tail call sequence, starting with first insn that hasn't been
2561 scanned yet, and note for each pseudo on the LHS whether it is based
2562 on crtl->args.internal_arg_pointer or not, and what offset from that
2563 that pointer it has. */
2566 internal_arg_pointer_based_exp_scan (void)
2568 rtx_insn
*insn
, *scan_start
= internal_arg_pointer_exp_state
.scan_start
;
2570 if (scan_start
== NULL_RTX
)
2571 insn
= get_insns ();
2573 insn
= NEXT_INSN (scan_start
);
2577 rtx set
= single_set (insn
);
2578 if (set
&& REG_P (SET_DEST (set
)) && !HARD_REGISTER_P (SET_DEST (set
)))
2581 unsigned int idx
= REGNO (SET_DEST (set
)) - FIRST_PSEUDO_REGISTER
;
2582 /* Punt on pseudos set multiple times. */
2583 if (idx
< internal_arg_pointer_exp_state
.cache
.length ()
2584 && (internal_arg_pointer_exp_state
.cache
[idx
]
2588 val
= internal_arg_pointer_based_exp (SET_SRC (set
), false);
2589 if (val
!= NULL_RTX
)
2591 if (idx
>= internal_arg_pointer_exp_state
.cache
.length ())
2592 internal_arg_pointer_exp_state
.cache
2593 .safe_grow_cleared (idx
+ 1);
2594 internal_arg_pointer_exp_state
.cache
[idx
] = val
;
2597 if (NEXT_INSN (insn
) == NULL_RTX
)
2599 insn
= NEXT_INSN (insn
);
2602 internal_arg_pointer_exp_state
.scan_start
= scan_start
;
2605 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
2606 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
2607 it with fixed offset, or PC if this is with variable or unknown offset.
2608 TOPLEVEL is true if the function is invoked at the topmost level. */
2611 internal_arg_pointer_based_exp (const_rtx rtl
, bool toplevel
)
2613 if (CONSTANT_P (rtl
))
2616 if (rtl
== crtl
->args
.internal_arg_pointer
)
2619 if (REG_P (rtl
) && HARD_REGISTER_P (rtl
))
2623 if (GET_CODE (rtl
) == PLUS
&& poly_int_rtx_p (XEXP (rtl
, 1), &offset
))
2625 rtx val
= internal_arg_pointer_based_exp (XEXP (rtl
, 0), toplevel
);
2626 if (val
== NULL_RTX
|| val
== pc_rtx
)
2628 return plus_constant (Pmode
, val
, offset
);
2631 /* When called at the topmost level, scan pseudo assignments in between the
2632 last scanned instruction in the tail call sequence and the latest insn
2633 in that sequence. */
2635 internal_arg_pointer_based_exp_scan ();
2639 unsigned int idx
= REGNO (rtl
) - FIRST_PSEUDO_REGISTER
;
2640 if (idx
< internal_arg_pointer_exp_state
.cache
.length ())
2641 return internal_arg_pointer_exp_state
.cache
[idx
];
2646 subrtx_iterator::array_type array
;
2647 FOR_EACH_SUBRTX (iter
, array
, rtl
, NONCONST
)
2649 const_rtx x
= *iter
;
2650 if (REG_P (x
) && internal_arg_pointer_based_exp (x
, false) != NULL_RTX
)
2653 iter
.skip_subrtxes ();
2659 /* Return true if SIZE bytes starting from address ADDR might overlap an
2660 already-clobbered argument area. This function is used to determine
2661 if we should give up a sibcall. */
2664 mem_might_overlap_already_clobbered_arg_p (rtx addr
, poly_uint64 size
)
2667 unsigned HOST_WIDE_INT start
, end
;
2670 if (bitmap_empty_p (stored_args_map
)
2671 && stored_args_watermark
== HOST_WIDE_INT_M1U
)
2673 val
= internal_arg_pointer_based_exp (addr
, true);
2674 if (val
== NULL_RTX
)
2676 else if (!poly_int_rtx_p (val
, &i
))
2679 if (known_eq (size
, 0U))
2682 if (STACK_GROWS_DOWNWARD
)
2683 i
-= crtl
->args
.pretend_args_size
;
2685 i
+= crtl
->args
.pretend_args_size
;
2687 if (ARGS_GROW_DOWNWARD
)
2690 /* We can ignore any references to the function's pretend args,
2691 which at this point would manifest as negative values of I. */
2692 if (known_le (i
, 0) && known_le (size
, poly_uint64 (-i
)))
2695 start
= maybe_lt (i
, 0) ? 0 : constant_lower_bound (i
);
2696 if (!(i
+ size
).is_constant (&end
))
2697 end
= HOST_WIDE_INT_M1U
;
2699 if (end
> stored_args_watermark
)
2702 end
= MIN (end
, SBITMAP_SIZE (stored_args_map
));
2703 for (unsigned HOST_WIDE_INT k
= start
; k
< end
; ++k
)
2704 if (bitmap_bit_p (stored_args_map
, k
))
2710 /* Do the register loads required for any wholly-register parms or any
2711 parms which are passed both on the stack and in a register. Their
2712 expressions were already evaluated.
2714 Mark all register-parms as living through the call, putting these USE
2715 insns in the CALL_INSN_FUNCTION_USAGE field.
2717 When IS_SIBCALL, perform the check_sibcall_argument_overlap
2718 checking, setting *SIBCALL_FAILURE if appropriate. */
2721 load_register_parameters (struct arg_data
*args
, int num_actuals
,
2722 rtx
*call_fusage
, int flags
, int is_sibcall
,
2723 int *sibcall_failure
)
2727 for (i
= 0; i
< num_actuals
; i
++)
2729 rtx reg
= ((flags
& ECF_SIBCALL
)
2730 ? args
[i
].tail_call_reg
: args
[i
].reg
);
2733 int partial
= args
[i
].partial
;
2735 poly_int64 size
= 0;
2736 HOST_WIDE_INT const_size
= 0;
2737 rtx_insn
*before_arg
= get_last_insn ();
2738 /* Set non-negative if we must move a word at a time, even if
2739 just one word (e.g, partial == 4 && mode == DFmode). Set
2740 to -1 if we just use a normal move insn. This value can be
2741 zero if the argument is a zero size structure. */
2743 if (GET_CODE (reg
) == PARALLEL
)
2747 gcc_assert (partial
% UNITS_PER_WORD
== 0);
2748 nregs
= partial
/ UNITS_PER_WORD
;
2750 else if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
)
2752 /* Variable-sized parameters should be described by a
2753 PARALLEL instead. */
2754 const_size
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
2755 gcc_assert (const_size
>= 0);
2756 nregs
= (const_size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
2760 size
= GET_MODE_SIZE (args
[i
].mode
);
2762 /* Handle calls that pass values in multiple non-contiguous
2763 locations. The Irix 6 ABI has examples of this. */
2765 if (GET_CODE (reg
) == PARALLEL
)
2766 emit_group_move (reg
, args
[i
].parallel_value
);
2768 /* If simple case, just do move. If normal partial, store_one_arg
2769 has already loaded the register for us. In all other cases,
2770 load the register(s) from memory. */
2772 else if (nregs
== -1)
2774 emit_move_insn (reg
, args
[i
].value
);
2775 #ifdef BLOCK_REG_PADDING
2776 /* Handle case where we have a value that needs shifting
2777 up to the msb. eg. a QImode value and we're padding
2778 upward on a BYTES_BIG_ENDIAN machine. */
2779 if (args
[i
].locate
.where_pad
2780 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
))
2782 gcc_checking_assert (ordered_p (size
, UNITS_PER_WORD
));
2783 if (maybe_lt (size
, UNITS_PER_WORD
))
2787 = (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2789 /* Assigning REG here rather than a temp makes
2790 CALL_FUSAGE report the whole reg as used.
2791 Strictly speaking, the call only uses SIZE
2792 bytes at the msb end, but it doesn't seem worth
2793 generating rtl to say that. */
2794 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
2795 x
= expand_shift (LSHIFT_EXPR
, word_mode
,
2796 reg
, shift
, reg
, 1);
2798 emit_move_insn (reg
, x
);
2804 /* If we have pre-computed the values to put in the registers in
2805 the case of non-aligned structures, copy them in now. */
2807 else if (args
[i
].n_aligned_regs
!= 0)
2808 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
2809 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
2810 args
[i
].aligned_regs
[j
]);
2812 else if (partial
== 0 || args
[i
].pass_on_stack
)
2814 /* SIZE and CONST_SIZE are 0 for partial arguments and
2815 the size of a BLKmode type otherwise. */
2816 gcc_checking_assert (known_eq (size
, const_size
));
2817 rtx mem
= validize_mem (copy_rtx (args
[i
].value
));
2819 /* Check for overlap with already clobbered argument area,
2820 providing that this has non-zero size. */
2823 && (mem_might_overlap_already_clobbered_arg_p
2824 (XEXP (args
[i
].value
, 0), const_size
)))
2825 *sibcall_failure
= 1;
2827 if (const_size
% UNITS_PER_WORD
== 0
2828 || MEM_ALIGN (mem
) % BITS_PER_WORD
== 0)
2829 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
2833 move_block_to_reg (REGNO (reg
), mem
, nregs
- 1,
2835 rtx dest
= gen_rtx_REG (word_mode
, REGNO (reg
) + nregs
- 1);
2836 unsigned int bitoff
= (nregs
- 1) * BITS_PER_WORD
;
2837 unsigned int bitsize
= const_size
* BITS_PER_UNIT
- bitoff
;
2838 rtx x
= extract_bit_field (mem
, bitsize
, bitoff
, 1, dest
,
2839 word_mode
, word_mode
, false,
2841 if (BYTES_BIG_ENDIAN
)
2842 x
= expand_shift (LSHIFT_EXPR
, word_mode
, x
,
2843 BITS_PER_WORD
- bitsize
, dest
, 1);
2845 emit_move_insn (dest
, x
);
2848 /* Handle a BLKmode that needs shifting. */
2849 if (nregs
== 1 && const_size
< UNITS_PER_WORD
2850 #ifdef BLOCK_REG_PADDING
2851 && args
[i
].locate
.where_pad
== PAD_DOWNWARD
2857 rtx dest
= gen_rtx_REG (word_mode
, REGNO (reg
));
2858 int shift
= (UNITS_PER_WORD
- const_size
) * BITS_PER_UNIT
;
2859 enum tree_code dir
= (BYTES_BIG_ENDIAN
2860 ? RSHIFT_EXPR
: LSHIFT_EXPR
);
2863 x
= expand_shift (dir
, word_mode
, dest
, shift
, dest
, 1);
2865 emit_move_insn (dest
, x
);
2869 /* When a parameter is a block, and perhaps in other cases, it is
2870 possible that it did a load from an argument slot that was
2871 already clobbered. */
2873 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
2874 *sibcall_failure
= 1;
2876 /* Handle calls that pass values in multiple non-contiguous
2877 locations. The Irix 6 ABI has examples of this. */
2878 if (GET_CODE (reg
) == PARALLEL
)
2879 use_group_regs (call_fusage
, reg
);
2880 else if (nregs
== -1)
2881 use_reg_mode (call_fusage
, reg
,
2882 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)));
2884 use_regs (call_fusage
, REGNO (reg
), nregs
);
2889 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2890 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2891 bytes, then we would need to push some additional bytes to pad the
2892 arguments. So, we try to compute an adjust to the stack pointer for an
2893 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2894 bytes. Then, when the arguments are pushed the stack will be perfectly
2897 Return true if this optimization is possible, storing the adjustment
2898 in ADJUSTMENT_OUT and setting ARGS_SIZE->CONSTANT to the number of
2899 bytes that should be popped after the call. */
2902 combine_pending_stack_adjustment_and_call (poly_int64_pod
*adjustment_out
,
2903 poly_int64 unadjusted_args_size
,
2904 struct args_size
*args_size
,
2905 unsigned int preferred_unit_stack_boundary
)
2907 /* The number of bytes to pop so that the stack will be
2908 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2909 poly_int64 adjustment
;
2910 /* The alignment of the stack after the arguments are pushed, if we
2911 just pushed the arguments without adjust the stack here. */
2912 unsigned HOST_WIDE_INT unadjusted_alignment
;
2914 if (!known_misalignment (stack_pointer_delta
+ unadjusted_args_size
,
2915 preferred_unit_stack_boundary
,
2916 &unadjusted_alignment
))
2919 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2920 as possible -- leaving just enough left to cancel out the
2921 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2922 PENDING_STACK_ADJUST is non-negative, and congruent to
2923 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2925 /* Begin by trying to pop all the bytes. */
2926 unsigned HOST_WIDE_INT tmp_misalignment
;
2927 if (!known_misalignment (pending_stack_adjust
,
2928 preferred_unit_stack_boundary
,
2931 unadjusted_alignment
-= tmp_misalignment
;
2932 adjustment
= pending_stack_adjust
;
2933 /* Push enough additional bytes that the stack will be aligned
2934 after the arguments are pushed. */
2935 if (preferred_unit_stack_boundary
> 1 && unadjusted_alignment
)
2936 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
2938 /* We need to know whether the adjusted argument size
2939 (UNADJUSTED_ARGS_SIZE - ADJUSTMENT) constitutes an allocation
2940 or a deallocation. */
2941 if (!ordered_p (adjustment
, unadjusted_args_size
))
2944 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2945 bytes after the call. The right number is the entire
2946 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2947 by the arguments in the first place. */
2949 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
2951 *adjustment_out
= adjustment
;
2955 /* Scan X expression if it does not dereference any argument slots
2956 we already clobbered by tail call arguments (as noted in stored_args_map
2958 Return nonzero if X expression dereferences such argument slots,
2962 check_sibcall_argument_overlap_1 (rtx x
)
2971 code
= GET_CODE (x
);
2973 /* We need not check the operands of the CALL expression itself. */
2978 return (mem_might_overlap_already_clobbered_arg_p
2979 (XEXP (x
, 0), GET_MODE_SIZE (GET_MODE (x
))));
2981 /* Scan all subexpressions. */
2982 fmt
= GET_RTX_FORMAT (code
);
2983 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
2987 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
2990 else if (*fmt
== 'E')
2992 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2993 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
3000 /* Scan sequence after INSN if it does not dereference any argument slots
3001 we already clobbered by tail call arguments (as noted in stored_args_map
3002 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
3003 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
3004 should be 0). Return nonzero if sequence after INSN dereferences such argument
3005 slots, zero otherwise. */
3008 check_sibcall_argument_overlap (rtx_insn
*insn
, struct arg_data
*arg
,
3009 int mark_stored_args_map
)
3011 poly_uint64 low
, high
;
3012 unsigned HOST_WIDE_INT const_low
, const_high
;
3014 if (insn
== NULL_RTX
)
3015 insn
= get_insns ();
3017 insn
= NEXT_INSN (insn
);
3019 for (; insn
; insn
= NEXT_INSN (insn
))
3021 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
3024 if (mark_stored_args_map
)
3026 if (ARGS_GROW_DOWNWARD
)
3027 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
3029 low
= arg
->locate
.slot_offset
.constant
;
3030 high
= low
+ arg
->locate
.size
.constant
;
3032 const_low
= constant_lower_bound (low
);
3033 if (high
.is_constant (&const_high
))
3034 for (unsigned HOST_WIDE_INT i
= const_low
; i
< const_high
; ++i
)
3035 bitmap_set_bit (stored_args_map
, i
);
3037 stored_args_watermark
= MIN (stored_args_watermark
, const_low
);
3039 return insn
!= NULL_RTX
;
3042 /* Given that a function returns a value of mode MODE at the most
3043 significant end of hard register VALUE, shift VALUE left or right
3044 as specified by LEFT_P. Return true if some action was needed. */
3047 shift_return_value (machine_mode mode
, bool left_p
, rtx value
)
3049 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
3050 machine_mode value_mode
= GET_MODE (value
);
3051 poly_int64 shift
= GET_MODE_BITSIZE (value_mode
) - GET_MODE_BITSIZE (mode
);
3053 if (known_eq (shift
, 0))
3056 /* Use ashr rather than lshr for right shifts. This is for the benefit
3057 of the MIPS port, which requires SImode values to be sign-extended
3058 when stored in 64-bit registers. */
3059 if (!force_expand_binop (value_mode
, left_p
? ashl_optab
: ashr_optab
,
3060 value
, gen_int_shift_amount (value_mode
, shift
),
3061 value
, 1, OPTAB_WIDEN
))
3066 /* If X is a likely-spilled register value, copy it to a pseudo
3067 register and return that register. Return X otherwise. */
3070 avoid_likely_spilled_reg (rtx x
)
3075 && HARD_REGISTER_P (x
)
3076 && targetm
.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x
))))
3078 /* Make sure that we generate a REG rather than a CONCAT.
3079 Moves into CONCATs can need nontrivial instructions,
3080 and the whole point of this function is to avoid
3081 using the hard register directly in such a situation. */
3082 generating_concat_p
= 0;
3083 new_rtx
= gen_reg_rtx (GET_MODE (x
));
3084 generating_concat_p
= 1;
3085 emit_move_insn (new_rtx
, x
);
3091 /* Helper function for expand_call.
3092 Return false is EXP is not implementable as a sibling call. */
3095 can_implement_as_sibling_call_p (tree exp
,
3096 rtx structure_value_addr
,
3098 int reg_parm_stack_space ATTRIBUTE_UNUSED
,
3102 const args_size
&args_size
)
3104 if (!targetm
.have_sibcall_epilogue ())
3106 maybe_complain_about_tail_call
3108 "machine description does not have"
3109 " a sibcall_epilogue instruction pattern");
3113 /* Doing sibling call optimization needs some work, since
3114 structure_value_addr can be allocated on the stack.
3115 It does not seem worth the effort since few optimizable
3116 sibling calls will return a structure. */
3117 if (structure_value_addr
!= NULL_RTX
)
3119 maybe_complain_about_tail_call (exp
, "callee returns a structure");
3123 #ifdef REG_PARM_STACK_SPACE
3124 /* If outgoing reg parm stack space changes, we can not do sibcall. */
3125 if (OUTGOING_REG_PARM_STACK_SPACE (funtype
)
3126 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl
))
3127 || (reg_parm_stack_space
!= REG_PARM_STACK_SPACE (current_function_decl
)))
3129 maybe_complain_about_tail_call (exp
,
3130 "inconsistent size of stack space"
3131 " allocated for arguments which are"
3132 " passed in registers");
3137 /* Check whether the target is able to optimize the call
3139 if (!targetm
.function_ok_for_sibcall (fndecl
, exp
))
3141 maybe_complain_about_tail_call (exp
,
3142 "target is not able to optimize the"
3143 " call into a sibling call");
3147 /* Functions that do not return exactly once may not be sibcall
3149 if (flags
& ECF_RETURNS_TWICE
)
3151 maybe_complain_about_tail_call (exp
, "callee returns twice");
3154 if (flags
& ECF_NORETURN
)
3156 maybe_complain_about_tail_call (exp
, "callee does not return");
3160 if (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
))))
3162 maybe_complain_about_tail_call (exp
, "volatile function type");
3166 /* If the called function is nested in the current one, it might access
3167 some of the caller's arguments, but could clobber them beforehand if
3168 the argument areas are shared. */
3169 if (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
3171 maybe_complain_about_tail_call (exp
, "nested function");
3175 /* If this function requires more stack slots than the current
3176 function, we cannot change it into a sibling call.
3177 crtl->args.pretend_args_size is not part of the
3178 stack allocated by our caller. */
3179 if (maybe_gt (args_size
.constant
,
3180 crtl
->args
.size
- crtl
->args
.pretend_args_size
))
3182 maybe_complain_about_tail_call (exp
,
3183 "callee required more stack slots"
3184 " than the caller");
3188 /* If the callee pops its own arguments, then it must pop exactly
3189 the same number of arguments as the current function. */
3190 if (maybe_ne (targetm
.calls
.return_pops_args (fndecl
, funtype
,
3191 args_size
.constant
),
3192 targetm
.calls
.return_pops_args (current_function_decl
,
3194 (current_function_decl
),
3197 maybe_complain_about_tail_call (exp
,
3198 "inconsistent number of"
3199 " popped arguments");
3203 if (!lang_hooks
.decls
.ok_for_sibcall (fndecl
))
3205 maybe_complain_about_tail_call (exp
, "frontend does not support"
3210 /* All checks passed. */
3214 /* Generate all the code for a CALL_EXPR exp
3215 and return an rtx for its value.
3216 Store the value in TARGET (specified as an rtx) if convenient.
3217 If the value is stored in TARGET then TARGET is returned.
3218 If IGNORE is nonzero, then we ignore the value of the function call. */
3221 expand_call (tree exp
, rtx target
, int ignore
)
3223 /* Nonzero if we are currently expanding a call. */
3224 static int currently_expanding_call
= 0;
3226 /* RTX for the function to be called. */
3228 /* Sequence of insns to perform a normal "call". */
3229 rtx_insn
*normal_call_insns
= NULL
;
3230 /* Sequence of insns to perform a tail "call". */
3231 rtx_insn
*tail_call_insns
= NULL
;
3232 /* Data type of the function. */
3234 tree type_arg_types
;
3236 /* Declaration of the function being called,
3237 or 0 if the function is computed (not known by name). */
3239 /* The type of the function being called. */
3241 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
3242 bool must_tail_call
= CALL_EXPR_MUST_TAIL_CALL (exp
);
3245 /* Register in which non-BLKmode value will be returned,
3246 or 0 if no value or if value is BLKmode. */
3248 /* Address where we should return a BLKmode value;
3249 0 if value not BLKmode. */
3250 rtx structure_value_addr
= 0;
3251 /* Nonzero if that address is being passed by treating it as
3252 an extra, implicit first parameter. Otherwise,
3253 it is passed by being copied directly into struct_value_rtx. */
3254 int structure_value_addr_parm
= 0;
3255 /* Holds the value of implicit argument for the struct value. */
3256 tree structure_value_addr_value
= NULL_TREE
;
3257 /* Size of aggregate value wanted, or zero if none wanted
3258 or if we are using the non-reentrant PCC calling convention
3259 or expecting the value in registers. */
3260 poly_int64 struct_value_size
= 0;
3261 /* Nonzero if called function returns an aggregate in memory PCC style,
3262 by returning the address of where to find it. */
3263 int pcc_struct_value
= 0;
3264 rtx struct_value
= 0;
3266 /* Number of actual parameters in this call, including struct value addr. */
3268 /* Number of named args. Args after this are anonymous ones
3269 and they must all go on the stack. */
3271 /* Number of complex actual arguments that need to be split. */
3272 int num_complex_actuals
= 0;
3274 /* Vector of information about each argument.
3275 Arguments are numbered in the order they will be pushed,
3276 not the order they are written. */
3277 struct arg_data
*args
;
3279 /* Total size in bytes of all the stack-parms scanned so far. */
3280 struct args_size args_size
;
3281 struct args_size adjusted_args_size
;
3282 /* Size of arguments before any adjustments (such as rounding). */
3283 poly_int64 unadjusted_args_size
;
3284 /* Data on reg parms scanned so far. */
3285 CUMULATIVE_ARGS args_so_far_v
;
3286 cumulative_args_t args_so_far
;
3287 /* Nonzero if a reg parm has been scanned. */
3289 /* Nonzero if this is an indirect function call. */
3291 /* Nonzero if we must avoid push-insns in the args for this call.
3292 If stack space is allocated for register parameters, but not by the
3293 caller, then it is preallocated in the fixed part of the stack frame.
3294 So the entire argument block must then be preallocated (i.e., we
3295 ignore PUSH_ROUNDING in that case). */
3297 int must_preallocate
= !PUSH_ARGS
;
3299 /* Size of the stack reserved for parameter registers. */
3300 int reg_parm_stack_space
= 0;
3302 /* Address of space preallocated for stack parms
3303 (on machines that lack push insns), or 0 if space not preallocated. */
3306 /* Mask of ECF_ and ERF_ flags. */
3308 int return_flags
= 0;
3309 #ifdef REG_PARM_STACK_SPACE
3310 /* Define the boundary of the register parm stack space that needs to be
3312 int low_to_save
, high_to_save
;
3313 rtx save_area
= 0; /* Place that it is saved */
3316 unsigned int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3317 char *initial_stack_usage_map
= stack_usage_map
;
3318 unsigned HOST_WIDE_INT initial_stack_usage_watermark
= stack_usage_watermark
;
3319 char *stack_usage_map_buf
= NULL
;
3321 poly_int64 old_stack_allocated
;
3323 /* State variables to track stack modifications. */
3324 rtx old_stack_level
= 0;
3325 int old_stack_arg_under_construction
= 0;
3326 poly_int64 old_pending_adj
= 0;
3327 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3329 /* Some stack pointer alterations we make are performed via
3330 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
3331 which we then also need to save/restore along the way. */
3332 poly_int64 old_stack_pointer_delta
= 0;
3335 tree addr
= CALL_EXPR_FN (exp
);
3337 /* The alignment of the stack, in bits. */
3338 unsigned HOST_WIDE_INT preferred_stack_boundary
;
3339 /* The alignment of the stack, in bytes. */
3340 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
3341 /* The static chain value to use for this call. */
3342 rtx static_chain_value
;
3343 /* See if this is "nothrow" function call. */
3344 if (TREE_NOTHROW (exp
))
3345 flags
|= ECF_NOTHROW
;
3347 /* See if we can find a DECL-node for the actual function, and get the
3348 function attributes (flags) from the function decl or type node. */
3349 fndecl
= get_callee_fndecl (exp
);
3352 fntype
= TREE_TYPE (fndecl
);
3353 flags
|= flags_from_decl_or_type (fndecl
);
3354 return_flags
|= decl_return_flags (fndecl
);
3358 fntype
= TREE_TYPE (TREE_TYPE (addr
));
3359 flags
|= flags_from_decl_or_type (fntype
);
3360 if (CALL_EXPR_BY_DESCRIPTOR (exp
))
3361 flags
|= ECF_BY_DESCRIPTOR
;
3363 rettype
= TREE_TYPE (exp
);
3365 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
3367 /* Warn if this value is an aggregate type,
3368 regardless of which calling convention we are using for it. */
3369 if (AGGREGATE_TYPE_P (rettype
))
3370 warning (OPT_Waggregate_return
, "function call has aggregate value");
3372 /* If the result of a non looping pure or const function call is
3373 ignored (or void), and none of its arguments are volatile, we can
3374 avoid expanding the call and just evaluate the arguments for
3376 if ((flags
& (ECF_CONST
| ECF_PURE
))
3377 && (!(flags
& ECF_LOOPING_CONST_OR_PURE
))
3378 && (ignore
|| target
== const0_rtx
3379 || TYPE_MODE (rettype
) == VOIDmode
))
3381 bool volatilep
= false;
3383 call_expr_arg_iterator iter
;
3385 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3386 if (TREE_THIS_VOLATILE (arg
))
3394 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3395 expand_expr (arg
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
3400 #ifdef REG_PARM_STACK_SPACE
3401 reg_parm_stack_space
= REG_PARM_STACK_SPACE (!fndecl
? fntype
: fndecl
);
3404 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
3405 && reg_parm_stack_space
> 0 && PUSH_ARGS
)
3406 must_preallocate
= 1;
3408 /* Set up a place to return a structure. */
3410 /* Cater to broken compilers. */
3411 if (aggregate_value_p (exp
, fntype
))
3413 /* This call returns a big structure. */
3414 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
3416 #ifdef PCC_STATIC_STRUCT_RETURN
3418 pcc_struct_value
= 1;
3420 #else /* not PCC_STATIC_STRUCT_RETURN */
3422 if (!poly_int_tree_p (TYPE_SIZE_UNIT (rettype
), &struct_value_size
))
3423 struct_value_size
= -1;
3425 /* Even if it is semantically safe to use the target as the return
3426 slot, it may be not sufficiently aligned for the return type. */
3427 if (CALL_EXPR_RETURN_SLOT_OPT (exp
)
3430 /* If rettype is addressable, we may not create a temporary.
3431 If target is properly aligned at runtime and the compiler
3432 just doesn't know about it, it will work fine, otherwise it
3434 && (TREE_ADDRESSABLE (rettype
)
3435 || !(MEM_ALIGN (target
) < TYPE_ALIGN (rettype
)
3436 && targetm
.slow_unaligned_access (TYPE_MODE (rettype
),
3437 MEM_ALIGN (target
)))))
3438 structure_value_addr
= XEXP (target
, 0);
3441 /* For variable-sized objects, we must be called with a target
3442 specified. If we were to allocate space on the stack here,
3443 we would have no way of knowing when to free it. */
3444 rtx d
= assign_temp (rettype
, 1, 1);
3445 structure_value_addr
= XEXP (d
, 0);
3449 #endif /* not PCC_STATIC_STRUCT_RETURN */
3452 /* Figure out the amount to which the stack should be aligned. */
3453 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3456 struct cgraph_rtl_info
*i
= cgraph_node::rtl_info (fndecl
);
3457 /* Without automatic stack alignment, we can't increase preferred
3458 stack boundary. With automatic stack alignment, it is
3459 unnecessary since unless we can guarantee that all callers will
3460 align the outgoing stack properly, callee has to align its
3463 && i
->preferred_incoming_stack_boundary
3464 && i
->preferred_incoming_stack_boundary
< preferred_stack_boundary
)
3465 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
3468 /* Operand 0 is a pointer-to-function; get the type of the function. */
3469 funtype
= TREE_TYPE (addr
);
3470 gcc_assert (POINTER_TYPE_P (funtype
));
3471 funtype
= TREE_TYPE (funtype
);
3473 /* Count whether there are actual complex arguments that need to be split
3474 into their real and imaginary parts. Munge the type_arg_types
3475 appropriately here as well. */
3476 if (targetm
.calls
.split_complex_arg
)
3478 call_expr_arg_iterator iter
;
3480 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
3482 tree type
= TREE_TYPE (arg
);
3483 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
3484 && targetm
.calls
.split_complex_arg (type
))
3485 num_complex_actuals
++;
3487 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
3490 type_arg_types
= TYPE_ARG_TYPES (funtype
);
3492 if (flags
& ECF_MAY_BE_ALLOCA
)
3493 cfun
->calls_alloca
= 1;
3495 /* If struct_value_rtx is 0, it means pass the address
3496 as if it were an extra parameter. Put the argument expression
3497 in structure_value_addr_value. */
3498 if (structure_value_addr
&& struct_value
== 0)
3500 /* If structure_value_addr is a REG other than
3501 virtual_outgoing_args_rtx, we can use always use it. If it
3502 is not a REG, we must always copy it into a register.
3503 If it is virtual_outgoing_args_rtx, we must copy it to another
3504 register in some cases. */
3505 rtx temp
= (!REG_P (structure_value_addr
)
3506 || (ACCUMULATE_OUTGOING_ARGS
3507 && stack_arg_under_construction
3508 && structure_value_addr
== virtual_outgoing_args_rtx
)
3509 ? copy_addr_to_reg (convert_memory_address
3510 (Pmode
, structure_value_addr
))
3511 : structure_value_addr
);
3513 structure_value_addr_value
=
3514 make_tree (build_pointer_type (TREE_TYPE (funtype
)), temp
);
3515 structure_value_addr_parm
= 1;
3518 /* Count the arguments and set NUM_ACTUALS. */
3520 call_expr_nargs (exp
) + num_complex_actuals
+ structure_value_addr_parm
;
3522 /* Compute number of named args.
3523 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
3525 if (type_arg_types
!= 0)
3527 = (list_length (type_arg_types
)
3528 /* Count the struct value address, if it is passed as a parm. */
3529 + structure_value_addr_parm
);
3531 /* If we know nothing, treat all args as named. */
3532 n_named_args
= num_actuals
;
3534 /* Start updating where the next arg would go.
3536 On some machines (such as the PA) indirect calls have a different
3537 calling convention than normal calls. The fourth argument in
3538 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
3540 INIT_CUMULATIVE_ARGS (args_so_far_v
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
3541 args_so_far
= pack_cumulative_args (&args_so_far_v
);
3543 /* Now possibly adjust the number of named args.
3544 Normally, don't include the last named arg if anonymous args follow.
3545 We do include the last named arg if
3546 targetm.calls.strict_argument_naming() returns nonzero.
3547 (If no anonymous args follow, the result of list_length is actually
3548 one too large. This is harmless.)
3550 If targetm.calls.pretend_outgoing_varargs_named() returns
3551 nonzero, and targetm.calls.strict_argument_naming() returns zero,
3552 this machine will be able to place unnamed args that were passed
3553 in registers into the stack. So treat all args as named. This
3554 allows the insns emitting for a specific argument list to be
3555 independent of the function declaration.
3557 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
3558 we do not have any reliable way to pass unnamed args in
3559 registers, so we must force them into memory. */
3561 if (type_arg_types
!= 0
3562 && targetm
.calls
.strict_argument_naming (args_so_far
))
3564 else if (type_arg_types
!= 0
3565 && ! targetm
.calls
.pretend_outgoing_varargs_named (args_so_far
))
3566 /* Don't include the last named arg. */
3569 /* Treat all args as named. */
3570 n_named_args
= num_actuals
;
3572 /* Make a vector to hold all the information about each arg. */
3573 args
= XCNEWVEC (struct arg_data
, num_actuals
);
3575 /* Build up entries in the ARGS array, compute the size of the
3576 arguments into ARGS_SIZE, etc. */
3577 initialize_argument_information (num_actuals
, args
, &args_size
,
3579 structure_value_addr_value
, fndecl
, fntype
,
3580 args_so_far
, reg_parm_stack_space
,
3581 &old_stack_level
, &old_pending_adj
,
3582 &must_preallocate
, &flags
,
3583 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
3586 must_preallocate
= 1;
3588 /* Now make final decision about preallocating stack space. */
3589 must_preallocate
= finalize_must_preallocate (must_preallocate
,
3593 /* If the structure value address will reference the stack pointer, we
3594 must stabilize it. We don't need to do this if we know that we are
3595 not going to adjust the stack pointer in processing this call. */
3597 if (structure_value_addr
3598 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
3599 || reg_mentioned_p (virtual_outgoing_args_rtx
,
3600 structure_value_addr
))
3602 || (!ACCUMULATE_OUTGOING_ARGS
3603 && maybe_ne (args_size
.constant
, 0))))
3604 structure_value_addr
= copy_to_reg (structure_value_addr
);
3606 /* Tail calls can make things harder to debug, and we've traditionally
3607 pushed these optimizations into -O2. Don't try if we're already
3608 expanding a call, as that means we're an argument. Don't try if
3609 there's cleanups, as we know there's code to follow the call. */
3611 if (currently_expanding_call
++ != 0
3612 || !flag_optimize_sibling_calls
3614 || dbg_cnt (tail_call
) == false)
3617 /* If the user has marked the function as requiring tail-call
3618 optimization, attempt it. */
3622 /* Rest of purposes for tail call optimizations to fail. */
3624 try_tail_call
= can_implement_as_sibling_call_p (exp
,
3625 structure_value_addr
,
3627 reg_parm_stack_space
,
3629 flags
, addr
, args_size
);
3631 /* Check if caller and callee disagree in promotion of function
3635 machine_mode caller_mode
, caller_promoted_mode
;
3636 machine_mode callee_mode
, callee_promoted_mode
;
3637 int caller_unsignedp
, callee_unsignedp
;
3638 tree caller_res
= DECL_RESULT (current_function_decl
);
3640 caller_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (caller_res
));
3641 caller_mode
= DECL_MODE (caller_res
);
3642 callee_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (funtype
));
3643 callee_mode
= TYPE_MODE (TREE_TYPE (funtype
));
3644 caller_promoted_mode
3645 = promote_function_mode (TREE_TYPE (caller_res
), caller_mode
,
3647 TREE_TYPE (current_function_decl
), 1);
3648 callee_promoted_mode
3649 = promote_function_mode (TREE_TYPE (funtype
), callee_mode
,
3652 if (caller_mode
!= VOIDmode
3653 && (caller_promoted_mode
!= callee_promoted_mode
3654 || ((caller_mode
!= caller_promoted_mode
3655 || callee_mode
!= callee_promoted_mode
)
3656 && (caller_unsignedp
!= callee_unsignedp
3657 || partial_subreg_p (caller_mode
, callee_mode
)))))
3660 maybe_complain_about_tail_call (exp
,
3661 "caller and callee disagree in"
3662 " promotion of function"
3667 /* Ensure current function's preferred stack boundary is at least
3668 what we need. Stack alignment may also increase preferred stack
3670 if (crtl
->preferred_stack_boundary
< preferred_stack_boundary
)
3671 crtl
->preferred_stack_boundary
= preferred_stack_boundary
;
3673 preferred_stack_boundary
= crtl
->preferred_stack_boundary
;
3675 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
3677 /* We want to make two insn chains; one for a sibling call, the other
3678 for a normal call. We will select one of the two chains after
3679 initial RTL generation is complete. */
3680 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
3682 int sibcall_failure
= 0;
3683 /* We want to emit any pending stack adjustments before the tail
3684 recursion "call". That way we know any adjustment after the tail
3685 recursion call can be ignored if we indeed use the tail
3687 saved_pending_stack_adjust save
;
3688 rtx_insn
*insns
, *before_call
, *after_args
;
3693 /* State variables we need to save and restore between
3695 save_pending_stack_adjust (&save
);
3698 flags
&= ~ECF_SIBCALL
;
3700 flags
|= ECF_SIBCALL
;
3702 /* Other state variables that we must reinitialize each time
3703 through the loop (that are not initialized by the loop itself). */
3707 /* Start a new sequence for the normal call case.
3709 From this point on, if the sibling call fails, we want to set
3710 sibcall_failure instead of continuing the loop. */
3713 /* Don't let pending stack adjusts add up to too much.
3714 Also, do all pending adjustments now if there is any chance
3715 this might be a call to alloca or if we are expanding a sibling
3717 Also do the adjustments before a throwing call, otherwise
3718 exception handling can fail; PR 19225. */
3719 if (maybe_ge (pending_stack_adjust
, 32)
3720 || (maybe_ne (pending_stack_adjust
, 0)
3721 && (flags
& ECF_MAY_BE_ALLOCA
))
3722 || (maybe_ne (pending_stack_adjust
, 0)
3723 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
3725 do_pending_stack_adjust ();
3727 /* Precompute any arguments as needed. */
3729 precompute_arguments (num_actuals
, args
);
3731 /* Now we are about to start emitting insns that can be deleted
3732 if a libcall is deleted. */
3733 if (pass
&& (flags
& ECF_MALLOC
))
3737 && crtl
->stack_protect_guard
3738 && targetm
.stack_protect_runtime_enabled_p ())
3739 stack_protect_epilogue ();
3741 adjusted_args_size
= args_size
;
3742 /* Compute the actual size of the argument block required. The variable
3743 and constant sizes must be combined, the size may have to be rounded,
3744 and there may be a minimum required size. When generating a sibcall
3745 pattern, do not round up, since we'll be re-using whatever space our
3747 unadjusted_args_size
3748 = compute_argument_block_size (reg_parm_stack_space
,
3749 &adjusted_args_size
,
3752 : preferred_stack_boundary
));
3754 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
3756 /* The argument block when performing a sibling call is the
3757 incoming argument block. */
3760 argblock
= crtl
->args
.internal_arg_pointer
;
3761 if (STACK_GROWS_DOWNWARD
)
3763 = plus_constant (Pmode
, argblock
, crtl
->args
.pretend_args_size
);
3766 = plus_constant (Pmode
, argblock
, -crtl
->args
.pretend_args_size
);
3768 HOST_WIDE_INT map_size
= constant_lower_bound (args_size
.constant
);
3769 stored_args_map
= sbitmap_alloc (map_size
);
3770 bitmap_clear (stored_args_map
);
3771 stored_args_watermark
= HOST_WIDE_INT_M1U
;
3774 /* If we have no actual push instructions, or shouldn't use them,
3775 make space for all args right now. */
3776 else if (adjusted_args_size
.var
!= 0)
3778 if (old_stack_level
== 0)
3780 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
3781 old_stack_pointer_delta
= stack_pointer_delta
;
3782 old_pending_adj
= pending_stack_adjust
;
3783 pending_stack_adjust
= 0;
3784 /* stack_arg_under_construction says whether a stack arg is
3785 being constructed at the old stack level. Pushing the stack
3786 gets a clean outgoing argument block. */
3787 old_stack_arg_under_construction
= stack_arg_under_construction
;
3788 stack_arg_under_construction
= 0;
3790 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
3791 if (flag_stack_usage_info
)
3792 current_function_has_unbounded_dynamic_stack_size
= 1;
3796 /* Note that we must go through the motions of allocating an argument
3797 block even if the size is zero because we may be storing args
3798 in the area reserved for register arguments, which may be part of
3801 poly_int64 needed
= adjusted_args_size
.constant
;
3803 /* Store the maximum argument space used. It will be pushed by
3804 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
3807 crtl
->outgoing_args_size
= upper_bound (crtl
->outgoing_args_size
,
3810 if (must_preallocate
)
3812 if (ACCUMULATE_OUTGOING_ARGS
)
3814 /* Since the stack pointer will never be pushed, it is
3815 possible for the evaluation of a parm to clobber
3816 something we have already written to the stack.
3817 Since most function calls on RISC machines do not use
3818 the stack, this is uncommon, but must work correctly.
3820 Therefore, we save any area of the stack that was already
3821 written and that we are using. Here we set up to do this
3822 by making a new stack usage map from the old one. The
3823 actual save will be done by store_one_arg.
3825 Another approach might be to try to reorder the argument
3826 evaluations to avoid this conflicting stack usage. */
3828 /* Since we will be writing into the entire argument area,
3829 the map must be allocated for its entire size, not just
3830 the part that is the responsibility of the caller. */
3831 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3832 needed
+= reg_parm_stack_space
;
3834 poly_int64 limit
= needed
;
3835 if (ARGS_GROW_DOWNWARD
)
3838 /* For polynomial sizes, this is the maximum possible
3839 size needed for arguments with a constant size
3841 HOST_WIDE_INT const_limit
= constant_lower_bound (limit
);
3842 highest_outgoing_arg_in_use
3843 = MAX (initial_highest_arg_in_use
, const_limit
);
3845 free (stack_usage_map_buf
);
3846 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
3847 stack_usage_map
= stack_usage_map_buf
;
3849 if (initial_highest_arg_in_use
)
3850 memcpy (stack_usage_map
, initial_stack_usage_map
,
3851 initial_highest_arg_in_use
);
3853 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3854 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3855 (highest_outgoing_arg_in_use
3856 - initial_highest_arg_in_use
));
3859 /* The address of the outgoing argument list must not be
3860 copied to a register here, because argblock would be left
3861 pointing to the wrong place after the call to
3862 allocate_dynamic_stack_space below. */
3864 argblock
= virtual_outgoing_args_rtx
;
3868 /* Try to reuse some or all of the pending_stack_adjust
3869 to get this space. */
3870 if (inhibit_defer_pop
== 0
3871 && (combine_pending_stack_adjustment_and_call
3873 unadjusted_args_size
,
3874 &adjusted_args_size
,
3875 preferred_unit_stack_boundary
)))
3877 /* combine_pending_stack_adjustment_and_call computes
3878 an adjustment before the arguments are allocated.
3879 Account for them and see whether or not the stack
3880 needs to go up or down. */
3881 needed
= unadjusted_args_size
- needed
;
3884 combine_pending_stack_adjustment_and_call. */
3885 gcc_checking_assert (ordered_p (needed
, 0));
3886 if (maybe_lt (needed
, 0))
3888 /* We're releasing stack space. */
3889 /* ??? We can avoid any adjustment at all if we're
3890 already aligned. FIXME. */
3891 pending_stack_adjust
= -needed
;
3892 do_pending_stack_adjust ();
3896 /* We need to allocate space. We'll do that in
3897 push_block below. */
3898 pending_stack_adjust
= 0;
3901 /* Special case this because overhead of `push_block' in
3902 this case is non-trivial. */
3903 if (known_eq (needed
, 0))
3904 argblock
= virtual_outgoing_args_rtx
;
3907 rtx needed_rtx
= gen_int_mode (needed
, Pmode
);
3908 argblock
= push_block (needed_rtx
, 0, 0);
3909 if (ARGS_GROW_DOWNWARD
)
3910 argblock
= plus_constant (Pmode
, argblock
, needed
);
3913 /* We only really need to call `copy_to_reg' in the case
3914 where push insns are going to be used to pass ARGBLOCK
3915 to a function call in ARGS. In that case, the stack
3916 pointer changes value from the allocation point to the
3917 call point, and hence the value of
3918 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3919 as well always do it. */
3920 argblock
= copy_to_reg (argblock
);
3925 if (ACCUMULATE_OUTGOING_ARGS
)
3927 /* The save/restore code in store_one_arg handles all
3928 cases except one: a constructor call (including a C
3929 function returning a BLKmode struct) to initialize
3931 if (stack_arg_under_construction
)
3935 (adjusted_args_size
.constant
3936 + (OUTGOING_REG_PARM_STACK_SPACE (!fndecl
? fntype
3937 : TREE_TYPE (fndecl
))
3938 ? 0 : reg_parm_stack_space
), Pmode
));
3939 if (old_stack_level
== 0)
3941 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
3942 old_stack_pointer_delta
= stack_pointer_delta
;
3943 old_pending_adj
= pending_stack_adjust
;
3944 pending_stack_adjust
= 0;
3945 /* stack_arg_under_construction says whether a stack
3946 arg is being constructed at the old stack level.
3947 Pushing the stack gets a clean outgoing argument
3949 old_stack_arg_under_construction
3950 = stack_arg_under_construction
;
3951 stack_arg_under_construction
= 0;
3952 /* Make a new map for the new argument list. */
3953 free (stack_usage_map_buf
);
3954 stack_usage_map_buf
= XCNEWVEC (char, highest_outgoing_arg_in_use
);
3955 stack_usage_map
= stack_usage_map_buf
;
3956 highest_outgoing_arg_in_use
= 0;
3957 stack_usage_watermark
= HOST_WIDE_INT_M1U
;
3959 /* We can pass TRUE as the 4th argument because we just
3960 saved the stack pointer and will restore it right after
3962 allocate_dynamic_stack_space (push_size
, 0, BIGGEST_ALIGNMENT
,
3966 /* If argument evaluation might modify the stack pointer,
3967 copy the address of the argument list to a register. */
3968 for (i
= 0; i
< num_actuals
; i
++)
3969 if (args
[i
].pass_on_stack
)
3971 argblock
= copy_addr_to_reg (argblock
);
3976 compute_argument_addresses (args
, argblock
, num_actuals
);
3978 /* Stack is properly aligned, pops can't safely be deferred during
3979 the evaluation of the arguments. */
3982 /* Precompute all register parameters. It isn't safe to compute
3983 anything once we have started filling any specific hard regs.
3984 TLS symbols sometimes need a call to resolve. Precompute
3985 register parameters before any stack pointer manipulation
3986 to avoid unaligned stack in the called function. */
3987 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
3991 /* Perform stack alignment before the first push (the last arg). */
3993 && maybe_gt (adjusted_args_size
.constant
, reg_parm_stack_space
)
3994 && maybe_ne (adjusted_args_size
.constant
, unadjusted_args_size
))
3996 /* When the stack adjustment is pending, we get better code
3997 by combining the adjustments. */
3998 if (maybe_ne (pending_stack_adjust
, 0)
3999 && ! inhibit_defer_pop
4000 && (combine_pending_stack_adjustment_and_call
4001 (&pending_stack_adjust
,
4002 unadjusted_args_size
,
4003 &adjusted_args_size
,
4004 preferred_unit_stack_boundary
)))
4005 do_pending_stack_adjust ();
4006 else if (argblock
== 0)
4007 anti_adjust_stack (gen_int_mode (adjusted_args_size
.constant
4008 - unadjusted_args_size
,
4011 /* Now that the stack is properly aligned, pops can't safely
4012 be deferred during the evaluation of the arguments. */
4015 /* Record the maximum pushed stack space size. We need to delay
4016 doing it this far to take into account the optimization done
4017 by combine_pending_stack_adjustment_and_call. */
4018 if (flag_stack_usage_info
4019 && !ACCUMULATE_OUTGOING_ARGS
4021 && adjusted_args_size
.var
== 0)
4023 poly_int64 pushed
= (adjusted_args_size
.constant
4024 + pending_stack_adjust
);
4025 current_function_pushed_stack_size
4026 = upper_bound (current_function_pushed_stack_size
, pushed
);
4029 funexp
= rtx_for_function_call (fndecl
, addr
);
4031 if (CALL_EXPR_STATIC_CHAIN (exp
))
4032 static_chain_value
= expand_normal (CALL_EXPR_STATIC_CHAIN (exp
));
4034 static_chain_value
= 0;
4036 #ifdef REG_PARM_STACK_SPACE
4037 /* Save the fixed argument area if it's part of the caller's frame and
4038 is clobbered by argument setup for this call. */
4039 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
4040 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
4041 &low_to_save
, &high_to_save
);
4044 /* Now store (and compute if necessary) all non-register parms.
4045 These come before register parms, since they can require block-moves,
4046 which could clobber the registers used for register parms.
4047 Parms which have partial registers are not stored here,
4048 but we do preallocate space here if they want that. */
4050 for (i
= 0; i
< num_actuals
; i
++)
4052 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
4054 rtx_insn
*before_arg
= get_last_insn ();
4056 /* We don't allow passing huge (> 2^30 B) arguments
4057 by value. It would cause an overflow later on. */
4058 if (constant_lower_bound (adjusted_args_size
.constant
)
4059 >= (1 << (HOST_BITS_PER_INT
- 2)))
4061 sorry ("passing too large argument on stack");
4065 if (store_one_arg (&args
[i
], argblock
, flags
,
4066 adjusted_args_size
.var
!= 0,
4067 reg_parm_stack_space
)
4069 && check_sibcall_argument_overlap (before_arg
,
4071 sibcall_failure
= 1;
4076 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
4077 gen_rtx_USE (VOIDmode
, args
[i
].stack
),
4081 /* If we have a parm that is passed in registers but not in memory
4082 and whose alignment does not permit a direct copy into registers,
4083 make a group of pseudos that correspond to each register that we
4085 if (STRICT_ALIGNMENT
)
4086 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
4088 /* Now store any partially-in-registers parm.
4089 This is the last place a block-move can happen. */
4091 for (i
= 0; i
< num_actuals
; i
++)
4092 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
4094 rtx_insn
*before_arg
= get_last_insn ();
4096 /* On targets with weird calling conventions (e.g. PA) it's
4097 hard to ensure that all cases of argument overlap between
4098 stack and registers work. Play it safe and bail out. */
4099 if (ARGS_GROW_DOWNWARD
&& !STACK_GROWS_DOWNWARD
)
4101 sibcall_failure
= 1;
4105 if (store_one_arg (&args
[i
], argblock
, flags
,
4106 adjusted_args_size
.var
!= 0,
4107 reg_parm_stack_space
)
4109 && check_sibcall_argument_overlap (before_arg
,
4111 sibcall_failure
= 1;
4114 bool any_regs
= false;
4115 for (i
= 0; i
< num_actuals
; i
++)
4116 if (args
[i
].reg
!= NULL_RTX
)
4119 targetm
.calls
.call_args (args
[i
].reg
, funtype
);
4122 targetm
.calls
.call_args (pc_rtx
, funtype
);
4124 /* Figure out the register where the value, if any, will come back. */
4126 if (TYPE_MODE (rettype
) != VOIDmode
4127 && ! structure_value_addr
)
4129 if (pcc_struct_value
)
4130 valreg
= hard_function_value (build_pointer_type (rettype
),
4131 fndecl
, NULL
, (pass
== 0));
4133 valreg
= hard_function_value (rettype
, fndecl
, fntype
,
4136 /* If VALREG is a PARALLEL whose first member has a zero
4137 offset, use that. This is for targets such as m68k that
4138 return the same value in multiple places. */
4139 if (GET_CODE (valreg
) == PARALLEL
)
4141 rtx elem
= XVECEXP (valreg
, 0, 0);
4142 rtx where
= XEXP (elem
, 0);
4143 rtx offset
= XEXP (elem
, 1);
4144 if (offset
== const0_rtx
4145 && GET_MODE (where
) == GET_MODE (valreg
))
4150 /* If register arguments require space on the stack and stack space
4151 was not preallocated, allocate stack space here for arguments
4152 passed in registers. */
4153 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
4154 && !ACCUMULATE_OUTGOING_ARGS
4155 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
4156 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
4158 /* Pass the function the address in which to return a
4160 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
4162 structure_value_addr
4163 = convert_memory_address (Pmode
, structure_value_addr
);
4164 emit_move_insn (struct_value
,
4166 force_operand (structure_value_addr
,
4169 if (REG_P (struct_value
))
4170 use_reg (&call_fusage
, struct_value
);
4173 after_args
= get_last_insn ();
4174 funexp
= prepare_call_address (fndecl
? fndecl
: fntype
, funexp
,
4175 static_chain_value
, &call_fusage
,
4176 reg_parm_seen
, flags
);
4178 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
4179 pass
== 0, &sibcall_failure
);
4181 /* Save a pointer to the last insn before the call, so that we can
4182 later safely search backwards to find the CALL_INSN. */
4183 before_call
= get_last_insn ();
4185 /* Set up next argument register. For sibling calls on machines
4186 with register windows this should be the incoming register. */
4188 next_arg_reg
= targetm
.calls
.function_incoming_arg (args_so_far
,
4193 next_arg_reg
= targetm
.calls
.function_arg (args_so_far
,
4194 VOIDmode
, void_type_node
,
4197 if (pass
== 1 && (return_flags
& ERF_RETURNS_ARG
))
4199 int arg_nr
= return_flags
& ERF_RETURN_ARG_MASK
;
4200 arg_nr
= num_actuals
- arg_nr
- 1;
4202 && arg_nr
< num_actuals
4206 && GET_MODE (args
[arg_nr
].reg
) == GET_MODE (valreg
))
4208 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args
[arg_nr
].tree_value
)),
4209 gen_rtx_SET (valreg
, args
[arg_nr
].reg
),
4212 /* All arguments and registers used for the call must be set up by
4215 /* Stack must be properly aligned now. */
4217 || multiple_p (stack_pointer_delta
,
4218 preferred_unit_stack_boundary
));
4220 /* Generate the actual call instruction. */
4221 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
4222 adjusted_args_size
.constant
, struct_value_size
,
4223 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
4224 flags
, args_so_far
);
4228 rtx_call_insn
*last
;
4229 rtx datum
= NULL_RTX
;
4230 if (fndecl
!= NULL_TREE
)
4232 datum
= XEXP (DECL_RTL (fndecl
), 0);
4233 gcc_assert (datum
!= NULL_RTX
4234 && GET_CODE (datum
) == SYMBOL_REF
);
4236 last
= last_call_insn ();
4237 add_reg_note (last
, REG_CALL_DECL
, datum
);
4240 /* If the call setup or the call itself overlaps with anything
4241 of the argument setup we probably clobbered our call address.
4242 In that case we can't do sibcalls. */
4244 && check_sibcall_argument_overlap (after_args
, 0, 0))
4245 sibcall_failure
= 1;
4247 /* If a non-BLKmode value is returned at the most significant end
4248 of a register, shift the register right by the appropriate amount
4249 and update VALREG accordingly. BLKmode values are handled by the
4250 group load/store machinery below. */
4251 if (!structure_value_addr
4252 && !pcc_struct_value
4253 && TYPE_MODE (rettype
) != VOIDmode
4254 && TYPE_MODE (rettype
) != BLKmode
4256 && targetm
.calls
.return_in_msb (rettype
))
4258 if (shift_return_value (TYPE_MODE (rettype
), false, valreg
))
4259 sibcall_failure
= 1;
4260 valreg
= gen_rtx_REG (TYPE_MODE (rettype
), REGNO (valreg
));
4263 if (pass
&& (flags
& ECF_MALLOC
))
4265 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
4266 rtx_insn
*last
, *insns
;
4268 /* The return value from a malloc-like function is a pointer. */
4269 if (TREE_CODE (rettype
) == POINTER_TYPE
)
4270 mark_reg_pointer (temp
, MALLOC_ABI_ALIGNMENT
);
4272 emit_move_insn (temp
, valreg
);
4274 /* The return value from a malloc-like function can not alias
4276 last
= get_last_insn ();
4277 add_reg_note (last
, REG_NOALIAS
, temp
);
4279 /* Write out the sequence. */
4280 insns
= get_insns ();
4286 /* For calls to `setjmp', etc., inform
4287 function.c:setjmp_warnings that it should complain if
4288 nonvolatile values are live. For functions that cannot
4289 return, inform flow that control does not fall through. */
4291 if ((flags
& ECF_NORETURN
) || pass
== 0)
4293 /* The barrier must be emitted
4294 immediately after the CALL_INSN. Some ports emit more
4295 than just a CALL_INSN above, so we must search for it here. */
4297 rtx_insn
*last
= get_last_insn ();
4298 while (!CALL_P (last
))
4300 last
= PREV_INSN (last
);
4301 /* There was no CALL_INSN? */
4302 gcc_assert (last
!= before_call
);
4305 emit_barrier_after (last
);
4307 /* Stack adjustments after a noreturn call are dead code.
4308 However when NO_DEFER_POP is in effect, we must preserve
4309 stack_pointer_delta. */
4310 if (inhibit_defer_pop
== 0)
4312 stack_pointer_delta
= old_stack_allocated
;
4313 pending_stack_adjust
= 0;
4317 /* If value type not void, return an rtx for the value. */
4319 if (TYPE_MODE (rettype
) == VOIDmode
4321 target
= const0_rtx
;
4322 else if (structure_value_addr
)
4324 if (target
== 0 || !MEM_P (target
))
4327 = gen_rtx_MEM (TYPE_MODE (rettype
),
4328 memory_address (TYPE_MODE (rettype
),
4329 structure_value_addr
));
4330 set_mem_attributes (target
, rettype
, 1);
4333 else if (pcc_struct_value
)
4335 /* This is the special C++ case where we need to
4336 know what the true target was. We take care to
4337 never use this value more than once in one expression. */
4338 target
= gen_rtx_MEM (TYPE_MODE (rettype
),
4339 copy_to_reg (valreg
));
4340 set_mem_attributes (target
, rettype
, 1);
4342 /* Handle calls that return values in multiple non-contiguous locations.
4343 The Irix 6 ABI has examples of this. */
4344 else if (GET_CODE (valreg
) == PARALLEL
)
4347 target
= emit_group_move_into_temps (valreg
);
4348 else if (rtx_equal_p (target
, valreg
))
4350 else if (GET_CODE (target
) == PARALLEL
)
4351 /* Handle the result of a emit_group_move_into_temps
4352 call in the previous pass. */
4353 emit_group_move (target
, valreg
);
4355 emit_group_store (target
, valreg
, rettype
,
4356 int_size_in_bytes (rettype
));
4359 && GET_MODE (target
) == TYPE_MODE (rettype
)
4360 && GET_MODE (target
) == GET_MODE (valreg
))
4362 bool may_overlap
= false;
4364 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
4365 reg to a plain register. */
4366 if (!REG_P (target
) || HARD_REGISTER_P (target
))
4367 valreg
= avoid_likely_spilled_reg (valreg
);
4369 /* If TARGET is a MEM in the argument area, and we have
4370 saved part of the argument area, then we can't store
4371 directly into TARGET as it may get overwritten when we
4372 restore the argument save area below. Don't work too
4373 hard though and simply force TARGET to a register if it
4374 is a MEM; the optimizer is quite likely to sort it out. */
4375 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
4376 for (i
= 0; i
< num_actuals
; i
++)
4377 if (args
[i
].save_area
)
4384 target
= copy_to_reg (valreg
);
4387 /* TARGET and VALREG cannot be equal at this point
4388 because the latter would not have
4389 REG_FUNCTION_VALUE_P true, while the former would if
4390 it were referring to the same register.
4392 If they refer to the same register, this move will be
4393 a no-op, except when function inlining is being
4395 emit_move_insn (target
, valreg
);
4397 /* If we are setting a MEM, this code must be executed.
4398 Since it is emitted after the call insn, sibcall
4399 optimization cannot be performed in that case. */
4401 sibcall_failure
= 1;
4405 target
= copy_to_reg (avoid_likely_spilled_reg (valreg
));
4407 /* If we promoted this return value, make the proper SUBREG.
4408 TARGET might be const0_rtx here, so be careful. */
4410 && TYPE_MODE (rettype
) != BLKmode
4411 && GET_MODE (target
) != TYPE_MODE (rettype
))
4413 tree type
= rettype
;
4414 int unsignedp
= TYPE_UNSIGNED (type
);
4417 /* Ensure we promote as expected, and get the new unsignedness. */
4418 pmode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
4420 gcc_assert (GET_MODE (target
) == pmode
);
4422 poly_uint64 offset
= subreg_lowpart_offset (TYPE_MODE (type
),
4424 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
4425 SUBREG_PROMOTED_VAR_P (target
) = 1;
4426 SUBREG_PROMOTED_SET (target
, unsignedp
);
4429 /* If size of args is variable or this was a constructor call for a stack
4430 argument, restore saved stack-pointer value. */
4432 if (old_stack_level
)
4434 rtx_insn
*prev
= get_last_insn ();
4436 emit_stack_restore (SAVE_BLOCK
, old_stack_level
);
4437 stack_pointer_delta
= old_stack_pointer_delta
;
4439 fixup_args_size_notes (prev
, get_last_insn (), stack_pointer_delta
);
4441 pending_stack_adjust
= old_pending_adj
;
4442 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
4443 stack_arg_under_construction
= old_stack_arg_under_construction
;
4444 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4445 stack_usage_map
= initial_stack_usage_map
;
4446 stack_usage_watermark
= initial_stack_usage_watermark
;
4447 sibcall_failure
= 1;
4449 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
4451 #ifdef REG_PARM_STACK_SPACE
4453 restore_fixed_argument_area (save_area
, argblock
,
4454 high_to_save
, low_to_save
);
4457 /* If we saved any argument areas, restore them. */
4458 for (i
= 0; i
< num_actuals
; i
++)
4459 if (args
[i
].save_area
)
4461 machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
4463 = gen_rtx_MEM (save_mode
,
4464 memory_address (save_mode
,
4465 XEXP (args
[i
].stack_slot
, 0)));
4467 if (save_mode
!= BLKmode
)
4468 emit_move_insn (stack_area
, args
[i
].save_area
);
4470 emit_block_move (stack_area
, args
[i
].save_area
,
4472 (args
[i
].locate
.size
.constant
, Pmode
)),
4473 BLOCK_OP_CALL_PARM
);
4476 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4477 stack_usage_map
= initial_stack_usage_map
;
4478 stack_usage_watermark
= initial_stack_usage_watermark
;
4481 /* If this was alloca, record the new stack level. */
4482 if (flags
& ECF_MAY_BE_ALLOCA
)
4483 record_new_stack_level ();
4485 /* Free up storage we no longer need. */
4486 for (i
= 0; i
< num_actuals
; ++i
)
4487 free (args
[i
].aligned_regs
);
4489 targetm
.calls
.end_call_args ();
4491 insns
= get_insns ();
4496 tail_call_insns
= insns
;
4498 /* Restore the pending stack adjustment now that we have
4499 finished generating the sibling call sequence. */
4501 restore_pending_stack_adjust (&save
);
4503 /* Prepare arg structure for next iteration. */
4504 for (i
= 0; i
< num_actuals
; i
++)
4507 args
[i
].aligned_regs
= 0;
4511 sbitmap_free (stored_args_map
);
4512 internal_arg_pointer_exp_state
.scan_start
= NULL
;
4513 internal_arg_pointer_exp_state
.cache
.release ();
4517 normal_call_insns
= insns
;
4519 /* Verify that we've deallocated all the stack we used. */
4520 gcc_assert ((flags
& ECF_NORETURN
)
4521 || known_eq (old_stack_allocated
,
4523 - pending_stack_adjust
));
4526 /* If something prevents making this a sibling call,
4527 zero out the sequence. */
4528 if (sibcall_failure
)
4529 tail_call_insns
= NULL
;
4534 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
4535 arguments too, as argument area is now clobbered by the call. */
4536 if (tail_call_insns
)
4538 emit_insn (tail_call_insns
);
4539 crtl
->tail_call_emit
= true;
4543 emit_insn (normal_call_insns
);
4545 /* Ideally we'd emit a message for all of the ways that it could
4547 maybe_complain_about_tail_call (exp
, "tail call production failed");
4550 currently_expanding_call
--;
4552 free (stack_usage_map_buf
);
4557 /* A sibling call sequence invalidates any REG_EQUIV notes made for
4558 this function's incoming arguments.
4560 At the start of RTL generation we know the only REG_EQUIV notes
4561 in the rtl chain are those for incoming arguments, so we can look
4562 for REG_EQUIV notes between the start of the function and the
4563 NOTE_INSN_FUNCTION_BEG.
4565 This is (slight) overkill. We could keep track of the highest
4566 argument we clobber and be more selective in removing notes, but it
4567 does not seem to be worth the effort. */
4570 fixup_tail_calls (void)
4574 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4578 /* There are never REG_EQUIV notes for the incoming arguments
4579 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
4581 && NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
)
4584 note
= find_reg_note (insn
, REG_EQUIV
, 0);
4586 remove_note (insn
, note
);
4587 note
= find_reg_note (insn
, REG_EQUIV
, 0);
4592 /* Traverse a list of TYPES and expand all complex types into their
4595 split_complex_types (tree types
)
4599 /* Before allocating memory, check for the common case of no complex. */
4600 for (p
= types
; p
; p
= TREE_CHAIN (p
))
4602 tree type
= TREE_VALUE (p
);
4603 if (TREE_CODE (type
) == COMPLEX_TYPE
4604 && targetm
.calls
.split_complex_arg (type
))
4610 types
= copy_list (types
);
4612 for (p
= types
; p
; p
= TREE_CHAIN (p
))
4614 tree complex_type
= TREE_VALUE (p
);
4616 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
4617 && targetm
.calls
.split_complex_arg (complex_type
))
4621 /* Rewrite complex type with component type. */
4622 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
4623 next
= TREE_CHAIN (p
);
4625 /* Add another component type for the imaginary part. */
4626 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
4627 TREE_CHAIN (p
) = imag
;
4628 TREE_CHAIN (imag
) = next
;
4630 /* Skip the newly created node. */
4638 /* Output a library call to function ORGFUN (a SYMBOL_REF rtx)
4639 for a value of mode OUTMODE,
4640 with NARGS different arguments, passed as ARGS.
4641 Store the return value if RETVAL is nonzero: store it in VALUE if
4642 VALUE is nonnull, otherwise pick a convenient location. In either
4643 case return the location of the stored value.
4645 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4646 `const' calls, LCT_PURE for `pure' calls, or another LCT_ value for
4647 other types of library calls. */
4650 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
4651 enum libcall_type fn_type
,
4652 machine_mode outmode
, int nargs
, rtx_mode_t
*args
)
4654 /* Total size in bytes of all the stack-parms scanned so far. */
4655 struct args_size args_size
;
4656 /* Size of arguments before any adjustments (such as rounding). */
4657 struct args_size original_args_size
;
4660 /* Todo, choose the correct decl type of orgfun. Sadly this information
4661 isn't present here, so we default to native calling abi here. */
4662 tree fndecl ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
4663 tree fntype ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
4666 CUMULATIVE_ARGS args_so_far_v
;
4667 cumulative_args_t args_so_far
;
4674 struct locate_and_pad_arg_data locate
;
4678 int old_inhibit_defer_pop
= inhibit_defer_pop
;
4679 rtx call_fusage
= 0;
4682 int pcc_struct_value
= 0;
4683 poly_int64 struct_value_size
= 0;
4685 int reg_parm_stack_space
= 0;
4687 rtx_insn
*before_call
;
4688 bool have_push_fusage
;
4689 tree tfom
; /* type_for_mode (outmode, 0) */
4691 #ifdef REG_PARM_STACK_SPACE
4692 /* Define the boundary of the register parm stack space that needs to be
4694 int low_to_save
= 0, high_to_save
= 0;
4695 rtx save_area
= 0; /* Place that it is saved. */
4698 /* Size of the stack reserved for parameter registers. */
4699 unsigned int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
4700 char *initial_stack_usage_map
= stack_usage_map
;
4701 unsigned HOST_WIDE_INT initial_stack_usage_watermark
= stack_usage_watermark
;
4702 char *stack_usage_map_buf
= NULL
;
4704 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
4706 #ifdef REG_PARM_STACK_SPACE
4707 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
4710 /* By default, library functions cannot throw. */
4711 flags
= ECF_NOTHROW
;
4724 flags
|= ECF_NORETURN
;
4727 flags
&= ~ECF_NOTHROW
;
4729 case LCT_RETURNS_TWICE
:
4730 flags
= ECF_RETURNS_TWICE
;
4735 /* Ensure current function's preferred stack boundary is at least
4737 if (crtl
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
4738 crtl
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
4740 /* If this kind of value comes back in memory,
4741 decide where in memory it should come back. */
4742 if (outmode
!= VOIDmode
)
4744 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
4745 if (aggregate_value_p (tfom
, 0))
4747 #ifdef PCC_STATIC_STRUCT_RETURN
4749 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
4750 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
4751 pcc_struct_value
= 1;
4753 value
= gen_reg_rtx (outmode
);
4754 #else /* not PCC_STATIC_STRUCT_RETURN */
4755 struct_value_size
= GET_MODE_SIZE (outmode
);
4756 if (value
!= 0 && MEM_P (value
))
4759 mem_value
= assign_temp (tfom
, 1, 1);
4761 /* This call returns a big structure. */
4762 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
4766 tfom
= void_type_node
;
4768 /* ??? Unfinished: must pass the memory address as an argument. */
4770 /* Copy all the libcall-arguments out of the varargs data
4771 and into a vector ARGVEC.
4773 Compute how to pass each argument. We only support a very small subset
4774 of the full argument passing conventions to limit complexity here since
4775 library functions shouldn't have many args. */
4777 argvec
= XALLOCAVEC (struct arg
, nargs
+ 1);
4778 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
4780 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
4781 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v
, outmode
, fun
);
4783 INIT_CUMULATIVE_ARGS (args_so_far_v
, NULL_TREE
, fun
, 0, nargs
);
4785 args_so_far
= pack_cumulative_args (&args_so_far_v
);
4787 args_size
.constant
= 0;
4794 /* If there's a structure value address to be passed,
4795 either pass it in the special place, or pass it as an extra argument. */
4796 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
4798 rtx addr
= XEXP (mem_value
, 0);
4802 /* Make sure it is a reasonable operand for a move or push insn. */
4803 if (!REG_P (addr
) && !MEM_P (addr
)
4804 && !(CONSTANT_P (addr
)
4805 && targetm
.legitimate_constant_p (Pmode
, addr
)))
4806 addr
= force_operand (addr
, NULL_RTX
);
4808 argvec
[count
].value
= addr
;
4809 argvec
[count
].mode
= Pmode
;
4810 argvec
[count
].partial
= 0;
4812 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
,
4813 Pmode
, NULL_TREE
, true);
4814 gcc_assert (targetm
.calls
.arg_partial_bytes (args_so_far
, Pmode
,
4815 NULL_TREE
, 1) == 0);
4817 locate_and_pad_parm (Pmode
, NULL_TREE
,
4818 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4821 argvec
[count
].reg
!= 0,
4823 reg_parm_stack_space
, 0,
4824 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
4826 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
4827 || reg_parm_stack_space
> 0)
4828 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
4830 targetm
.calls
.function_arg_advance (args_so_far
, Pmode
, (tree
) 0, true);
4835 for (unsigned int i
= 0; count
< nargs
; i
++, count
++)
4837 rtx val
= args
[i
].first
;
4838 machine_mode mode
= args
[i
].second
;
4841 /* We cannot convert the arg value to the mode the library wants here;
4842 must do it earlier where we know the signedness of the arg. */
4843 gcc_assert (mode
!= BLKmode
4844 && (GET_MODE (val
) == mode
|| GET_MODE (val
) == VOIDmode
));
4846 /* Make sure it is a reasonable operand for a move or push insn. */
4847 if (!REG_P (val
) && !MEM_P (val
)
4848 && !(CONSTANT_P (val
) && targetm
.legitimate_constant_p (mode
, val
)))
4849 val
= force_operand (val
, NULL_RTX
);
4851 if (pass_by_reference (&args_so_far_v
, mode
, NULL_TREE
, 1))
4855 = !reference_callee_copied (&args_so_far_v
, mode
, NULL_TREE
, 1);
4857 /* If this was a CONST function, it is now PURE since it now
4859 if (flags
& ECF_CONST
)
4861 flags
&= ~ECF_CONST
;
4865 if (MEM_P (val
) && !must_copy
)
4867 tree val_expr
= MEM_EXPR (val
);
4869 mark_addressable (val_expr
);
4874 slot
= assign_temp (lang_hooks
.types
.type_for_mode (mode
, 0),
4876 emit_move_insn (slot
, val
);
4879 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
4880 gen_rtx_USE (VOIDmode
, slot
),
4883 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
4884 gen_rtx_CLOBBER (VOIDmode
,
4889 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
4892 mode
= promote_function_mode (NULL_TREE
, mode
, &unsigned_p
, NULL_TREE
, 0);
4893 argvec
[count
].mode
= mode
;
4894 argvec
[count
].value
= convert_modes (mode
, GET_MODE (val
), val
, unsigned_p
);
4895 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
, mode
,
4898 argvec
[count
].partial
4899 = targetm
.calls
.arg_partial_bytes (args_so_far
, mode
, NULL_TREE
, 1);
4901 if (argvec
[count
].reg
== 0
4902 || argvec
[count
].partial
!= 0
4903 || reg_parm_stack_space
> 0)
4905 locate_and_pad_parm (mode
, NULL_TREE
,
4906 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4909 argvec
[count
].reg
!= 0,
4911 reg_parm_stack_space
, argvec
[count
].partial
,
4912 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
4913 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
4914 gcc_assert (!argvec
[count
].locate
.size
.var
);
4916 #ifdef BLOCK_REG_PADDING
4918 /* The argument is passed entirely in registers. See at which
4919 end it should be padded. */
4920 argvec
[count
].locate
.where_pad
=
4921 BLOCK_REG_PADDING (mode
, NULL_TREE
,
4922 known_le (GET_MODE_SIZE (mode
), UNITS_PER_WORD
));
4925 targetm
.calls
.function_arg_advance (args_so_far
, mode
, (tree
) 0, true);
4928 /* If this machine requires an external definition for library
4929 functions, write one out. */
4930 assemble_external_libcall (fun
);
4932 original_args_size
= args_size
;
4933 args_size
.constant
= (aligned_upper_bound (args_size
.constant
4934 + stack_pointer_delta
,
4936 - stack_pointer_delta
);
4938 args_size
.constant
= upper_bound (args_size
.constant
,
4939 reg_parm_stack_space
);
4941 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
4942 args_size
.constant
-= reg_parm_stack_space
;
4944 crtl
->outgoing_args_size
= upper_bound (crtl
->outgoing_args_size
,
4945 args_size
.constant
);
4947 if (flag_stack_usage_info
&& !ACCUMULATE_OUTGOING_ARGS
)
4949 poly_int64 pushed
= args_size
.constant
+ pending_stack_adjust
;
4950 current_function_pushed_stack_size
4951 = upper_bound (current_function_pushed_stack_size
, pushed
);
4954 if (ACCUMULATE_OUTGOING_ARGS
)
4956 /* Since the stack pointer will never be pushed, it is possible for
4957 the evaluation of a parm to clobber something we have already
4958 written to the stack. Since most function calls on RISC machines
4959 do not use the stack, this is uncommon, but must work correctly.
4961 Therefore, we save any area of the stack that was already written
4962 and that we are using. Here we set up to do this by making a new
4963 stack usage map from the old one.
4965 Another approach might be to try to reorder the argument
4966 evaluations to avoid this conflicting stack usage. */
4968 needed
= args_size
.constant
;
4970 /* Since we will be writing into the entire argument area, the
4971 map must be allocated for its entire size, not just the part that
4972 is the responsibility of the caller. */
4973 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
4974 needed
+= reg_parm_stack_space
;
4976 poly_int64 limit
= needed
;
4977 if (ARGS_GROW_DOWNWARD
)
4980 /* For polynomial sizes, this is the maximum possible size needed
4981 for arguments with a constant size and offset. */
4982 HOST_WIDE_INT const_limit
= constant_lower_bound (limit
);
4983 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
4986 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
4987 stack_usage_map
= stack_usage_map_buf
;
4989 if (initial_highest_arg_in_use
)
4990 memcpy (stack_usage_map
, initial_stack_usage_map
,
4991 initial_highest_arg_in_use
);
4993 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
4994 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
4995 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
4998 /* We must be careful to use virtual regs before they're instantiated,
4999 and real regs afterwards. Loop optimization, for example, can create
5000 new libcalls after we've instantiated the virtual regs, and if we
5001 use virtuals anyway, they won't match the rtl patterns. */
5003 if (virtuals_instantiated
)
5004 argblock
= plus_constant (Pmode
, stack_pointer_rtx
,
5005 STACK_POINTER_OFFSET
);
5007 argblock
= virtual_outgoing_args_rtx
;
5012 argblock
= push_block (gen_int_mode (args_size
.constant
, Pmode
), 0, 0);
5015 /* We push args individually in reverse order, perform stack alignment
5016 before the first push (the last arg). */
5018 anti_adjust_stack (gen_int_mode (args_size
.constant
5019 - original_args_size
.constant
,
5024 #ifdef REG_PARM_STACK_SPACE
5025 if (ACCUMULATE_OUTGOING_ARGS
)
5027 /* The argument list is the property of the called routine and it
5028 may clobber it. If the fixed area has been used for previous
5029 parameters, we must save and restore it. */
5030 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
5031 &low_to_save
, &high_to_save
);
5035 /* When expanding a normal call, args are stored in push order,
5036 which is the reverse of what we have here. */
5037 bool any_regs
= false;
5038 for (int i
= nargs
; i
-- > 0; )
5039 if (argvec
[i
].reg
!= NULL_RTX
)
5041 targetm
.calls
.call_args (argvec
[i
].reg
, NULL_TREE
);
5045 targetm
.calls
.call_args (pc_rtx
, NULL_TREE
);
5047 /* Push the args that need to be pushed. */
5049 have_push_fusage
= false;
5051 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5052 are to be pushed. */
5053 for (count
= 0; count
< nargs
; count
++, argnum
--)
5055 machine_mode mode
= argvec
[argnum
].mode
;
5056 rtx val
= argvec
[argnum
].value
;
5057 rtx reg
= argvec
[argnum
].reg
;
5058 int partial
= argvec
[argnum
].partial
;
5059 unsigned int parm_align
= argvec
[argnum
].locate
.boundary
;
5060 poly_int64 lower_bound
= 0, upper_bound
= 0;
5062 if (! (reg
!= 0 && partial
== 0))
5066 if (ACCUMULATE_OUTGOING_ARGS
)
5068 /* If this is being stored into a pre-allocated, fixed-size,
5069 stack area, save any previous data at that location. */
5071 if (ARGS_GROW_DOWNWARD
)
5073 /* stack_slot is negative, but we want to index stack_usage_map
5074 with positive values. */
5075 upper_bound
= -argvec
[argnum
].locate
.slot_offset
.constant
+ 1;
5076 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
5080 lower_bound
= argvec
[argnum
].locate
.slot_offset
.constant
;
5081 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
5084 if (stack_region_maybe_used_p (lower_bound
, upper_bound
,
5085 reg_parm_stack_space
))
5087 /* We need to make a save area. */
5089 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
5090 machine_mode save_mode
5091 = int_mode_for_size (size
, 1).else_blk ();
5093 = plus_constant (Pmode
, argblock
,
5094 argvec
[argnum
].locate
.offset
.constant
);
5096 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
5098 if (save_mode
== BLKmode
)
5100 argvec
[argnum
].save_area
5101 = assign_stack_temp (BLKmode
,
5102 argvec
[argnum
].locate
.size
.constant
5105 emit_block_move (validize_mem
5106 (copy_rtx (argvec
[argnum
].save_area
)),
5109 (argvec
[argnum
].locate
.size
.constant
,
5111 BLOCK_OP_CALL_PARM
);
5115 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
5117 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
5122 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, parm_align
,
5123 partial
, reg
, 0, argblock
,
5125 (argvec
[argnum
].locate
.offset
.constant
, Pmode
)),
5126 reg_parm_stack_space
,
5127 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
), false);
5129 /* Now mark the segment we just used. */
5130 if (ACCUMULATE_OUTGOING_ARGS
)
5131 mark_stack_region_used (lower_bound
, upper_bound
);
5135 /* Indicate argument access so that alias.c knows that these
5138 use
= plus_constant (Pmode
, argblock
,
5139 argvec
[argnum
].locate
.offset
.constant
);
5140 else if (have_push_fusage
)
5144 /* When arguments are pushed, trying to tell alias.c where
5145 exactly this argument is won't work, because the
5146 auto-increment causes confusion. So we merely indicate
5147 that we access something with a known mode somewhere on
5149 use
= gen_rtx_PLUS (Pmode
, stack_pointer_rtx
,
5150 gen_rtx_SCRATCH (Pmode
));
5151 have_push_fusage
= true;
5153 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
5154 use
= gen_rtx_USE (VOIDmode
, use
);
5155 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
5161 fun
= prepare_call_address (NULL
, fun
, NULL
, &call_fusage
, 0, 0);
5163 /* Now load any reg parms into their regs. */
5165 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5166 are to be pushed. */
5167 for (count
= 0; count
< nargs
; count
++, argnum
--)
5169 machine_mode mode
= argvec
[argnum
].mode
;
5170 rtx val
= argvec
[argnum
].value
;
5171 rtx reg
= argvec
[argnum
].reg
;
5172 int partial
= argvec
[argnum
].partial
;
5174 /* Handle calls that pass values in multiple non-contiguous
5175 locations. The PA64 has examples of this for library calls. */
5176 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
5177 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
5178 else if (reg
!= 0 && partial
== 0)
5180 emit_move_insn (reg
, val
);
5181 #ifdef BLOCK_REG_PADDING
5182 poly_int64 size
= GET_MODE_SIZE (argvec
[argnum
].mode
);
5184 /* Copied from load_register_parameters. */
5186 /* Handle case where we have a value that needs shifting
5187 up to the msb. eg. a QImode value and we're padding
5188 upward on a BYTES_BIG_ENDIAN machine. */
5189 if (known_lt (size
, UNITS_PER_WORD
)
5190 && (argvec
[argnum
].locate
.where_pad
5191 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
5194 poly_int64 shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
5196 /* Assigning REG here rather than a temp makes CALL_FUSAGE
5197 report the whole reg as used. Strictly speaking, the
5198 call only uses SIZE bytes at the msb end, but it doesn't
5199 seem worth generating rtl to say that. */
5200 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
5201 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
, shift
, reg
, 1);
5203 emit_move_insn (reg
, x
);
5211 /* Any regs containing parms remain in use through the call. */
5212 for (count
= 0; count
< nargs
; count
++)
5214 rtx reg
= argvec
[count
].reg
;
5215 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
5216 use_group_regs (&call_fusage
, reg
);
5219 int partial
= argvec
[count
].partial
;
5223 gcc_assert (partial
% UNITS_PER_WORD
== 0);
5224 nregs
= partial
/ UNITS_PER_WORD
;
5225 use_regs (&call_fusage
, REGNO (reg
), nregs
);
5228 use_reg (&call_fusage
, reg
);
5232 /* Pass the function the address in which to return a structure value. */
5233 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
5235 emit_move_insn (struct_value
,
5237 force_operand (XEXP (mem_value
, 0),
5239 if (REG_P (struct_value
))
5240 use_reg (&call_fusage
, struct_value
);
5243 /* Don't allow popping to be deferred, since then
5244 cse'ing of library calls could delete a call and leave the pop. */
5246 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
5247 ? hard_libcall_value (outmode
, orgfun
) : NULL_RTX
);
5249 /* Stack must be properly aligned now. */
5250 gcc_assert (multiple_p (stack_pointer_delta
,
5251 PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
));
5253 before_call
= get_last_insn ();
5255 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
5256 will set inhibit_defer_pop to that value. */
5257 /* The return type is needed to decide how many bytes the function pops.
5258 Signedness plays no role in that, so for simplicity, we pretend it's
5259 always signed. We also assume that the list of arguments passed has
5260 no impact, so we pretend it is unknown. */
5262 emit_call_1 (fun
, NULL
,
5263 get_identifier (XSTR (orgfun
, 0)),
5264 build_function_type (tfom
, NULL_TREE
),
5265 original_args_size
.constant
, args_size
.constant
,
5267 targetm
.calls
.function_arg (args_so_far
,
5268 VOIDmode
, void_type_node
, true),
5270 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, args_so_far
);
5275 gcc_assert (GET_CODE (datum
) == SYMBOL_REF
);
5276 rtx_call_insn
*last
= last_call_insn ();
5277 add_reg_note (last
, REG_CALL_DECL
, datum
);
5280 /* Right-shift returned value if necessary. */
5281 if (!pcc_struct_value
5282 && TYPE_MODE (tfom
) != BLKmode
5283 && targetm
.calls
.return_in_msb (tfom
))
5285 shift_return_value (TYPE_MODE (tfom
), false, valreg
);
5286 valreg
= gen_rtx_REG (TYPE_MODE (tfom
), REGNO (valreg
));
5289 targetm
.calls
.end_call_args ();
5291 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
5292 that it should complain if nonvolatile values are live. For
5293 functions that cannot return, inform flow that control does not
5295 if (flags
& ECF_NORETURN
)
5297 /* The barrier note must be emitted
5298 immediately after the CALL_INSN. Some ports emit more than
5299 just a CALL_INSN above, so we must search for it here. */
5300 rtx_insn
*last
= get_last_insn ();
5301 while (!CALL_P (last
))
5303 last
= PREV_INSN (last
);
5304 /* There was no CALL_INSN? */
5305 gcc_assert (last
!= before_call
);
5308 emit_barrier_after (last
);
5311 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
5312 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
5313 if (flags
& ECF_NOTHROW
)
5315 rtx_insn
*last
= get_last_insn ();
5316 while (!CALL_P (last
))
5318 last
= PREV_INSN (last
);
5319 /* There was no CALL_INSN? */
5320 gcc_assert (last
!= before_call
);
5323 make_reg_eh_region_note_nothrow_nononlocal (last
);
5326 /* Now restore inhibit_defer_pop to its actual original value. */
5331 /* Copy the value to the right place. */
5332 if (outmode
!= VOIDmode
&& retval
)
5338 if (value
!= mem_value
)
5339 emit_move_insn (value
, mem_value
);
5341 else if (GET_CODE (valreg
) == PARALLEL
)
5344 value
= gen_reg_rtx (outmode
);
5345 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
5349 /* Convert to the proper mode if a promotion has been active. */
5350 if (GET_MODE (valreg
) != outmode
)
5352 int unsignedp
= TYPE_UNSIGNED (tfom
);
5354 gcc_assert (promote_function_mode (tfom
, outmode
, &unsignedp
,
5355 fndecl
? TREE_TYPE (fndecl
) : fntype
, 1)
5356 == GET_MODE (valreg
));
5357 valreg
= convert_modes (outmode
, GET_MODE (valreg
), valreg
, 0);
5361 emit_move_insn (value
, valreg
);
5367 if (ACCUMULATE_OUTGOING_ARGS
)
5369 #ifdef REG_PARM_STACK_SPACE
5371 restore_fixed_argument_area (save_area
, argblock
,
5372 high_to_save
, low_to_save
);
5375 /* If we saved any argument areas, restore them. */
5376 for (count
= 0; count
< nargs
; count
++)
5377 if (argvec
[count
].save_area
)
5379 machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
5380 rtx adr
= plus_constant (Pmode
, argblock
,
5381 argvec
[count
].locate
.offset
.constant
);
5382 rtx stack_area
= gen_rtx_MEM (save_mode
,
5383 memory_address (save_mode
, adr
));
5385 if (save_mode
== BLKmode
)
5386 emit_block_move (stack_area
,
5388 (copy_rtx (argvec
[count
].save_area
)),
5390 (argvec
[count
].locate
.size
.constant
, Pmode
)),
5391 BLOCK_OP_CALL_PARM
);
5393 emit_move_insn (stack_area
, argvec
[count
].save_area
);
5396 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
5397 stack_usage_map
= initial_stack_usage_map
;
5398 stack_usage_watermark
= initial_stack_usage_watermark
;
5401 free (stack_usage_map_buf
);
5408 /* Store a single argument for a function call
5409 into the register or memory area where it must be passed.
5410 *ARG describes the argument value and where to pass it.
5412 ARGBLOCK is the address of the stack-block for all the arguments,
5413 or 0 on a machine where arguments are pushed individually.
5415 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
5416 so must be careful about how the stack is used.
5418 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
5419 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
5420 that we need not worry about saving and restoring the stack.
5422 FNDECL is the declaration of the function we are calling.
5424 Return nonzero if this arg should cause sibcall failure,
5428 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
5429 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
5431 tree pval
= arg
->tree_value
;
5434 poly_int64 used
= 0;
5435 poly_int64 lower_bound
= 0, upper_bound
= 0;
5436 int sibcall_failure
= 0;
5438 if (TREE_CODE (pval
) == ERROR_MARK
)
5441 /* Push a new temporary level for any temporaries we make for
5445 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
5447 /* If this is being stored into a pre-allocated, fixed-size, stack area,
5448 save any previous data at that location. */
5449 if (argblock
&& ! variable_size
&& arg
->stack
)
5451 if (ARGS_GROW_DOWNWARD
)
5453 /* stack_slot is negative, but we want to index stack_usage_map
5454 with positive values. */
5455 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
5457 rtx offset
= XEXP (XEXP (arg
->stack_slot
, 0), 1);
5458 upper_bound
= -rtx_to_poly_int64 (offset
) + 1;
5463 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
5467 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
5469 rtx offset
= XEXP (XEXP (arg
->stack_slot
, 0), 1);
5470 lower_bound
= rtx_to_poly_int64 (offset
);
5475 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
5478 if (stack_region_maybe_used_p (lower_bound
, upper_bound
,
5479 reg_parm_stack_space
))
5481 /* We need to make a save area. */
5482 poly_uint64 size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
5483 machine_mode save_mode
5484 = int_mode_for_size (size
, 1).else_blk ();
5485 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
5486 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
5488 if (save_mode
== BLKmode
)
5491 = assign_temp (TREE_TYPE (arg
->tree_value
), 1, 1);
5492 preserve_temp_slots (arg
->save_area
);
5493 emit_block_move (validize_mem (copy_rtx (arg
->save_area
)),
5496 (arg
->locate
.size
.constant
, Pmode
)),
5497 BLOCK_OP_CALL_PARM
);
5501 arg
->save_area
= gen_reg_rtx (save_mode
);
5502 emit_move_insn (arg
->save_area
, stack_area
);
5508 /* If this isn't going to be placed on both the stack and in registers,
5509 set up the register and number of words. */
5510 if (! arg
->pass_on_stack
)
5512 if (flags
& ECF_SIBCALL
)
5513 reg
= arg
->tail_call_reg
;
5516 partial
= arg
->partial
;
5519 /* Being passed entirely in a register. We shouldn't be called in
5521 gcc_assert (reg
== 0 || partial
!= 0);
5523 /* If this arg needs special alignment, don't load the registers
5525 if (arg
->n_aligned_regs
!= 0)
5528 /* If this is being passed partially in a register, we can't evaluate
5529 it directly into its stack slot. Otherwise, we can. */
5530 if (arg
->value
== 0)
5532 /* stack_arg_under_construction is nonzero if a function argument is
5533 being evaluated directly into the outgoing argument list and
5534 expand_call must take special action to preserve the argument list
5535 if it is called recursively.
5537 For scalar function arguments stack_usage_map is sufficient to
5538 determine which stack slots must be saved and restored. Scalar
5539 arguments in general have pass_on_stack == 0.
5541 If this argument is initialized by a function which takes the
5542 address of the argument (a C++ constructor or a C function
5543 returning a BLKmode structure), then stack_usage_map is
5544 insufficient and expand_call must push the stack around the
5545 function call. Such arguments have pass_on_stack == 1.
5547 Note that it is always safe to set stack_arg_under_construction,
5548 but this generates suboptimal code if set when not needed. */
5550 if (arg
->pass_on_stack
)
5551 stack_arg_under_construction
++;
5553 arg
->value
= expand_expr (pval
,
5555 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
5556 ? NULL_RTX
: arg
->stack
,
5557 VOIDmode
, EXPAND_STACK_PARM
);
5559 /* If we are promoting object (or for any other reason) the mode
5560 doesn't agree, convert the mode. */
5562 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
5563 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
5564 arg
->value
, arg
->unsignedp
);
5566 if (arg
->pass_on_stack
)
5567 stack_arg_under_construction
--;
5570 /* Check for overlap with already clobbered argument area. */
5571 if ((flags
& ECF_SIBCALL
)
5572 && MEM_P (arg
->value
)
5573 && mem_might_overlap_already_clobbered_arg_p (XEXP (arg
->value
, 0),
5574 arg
->locate
.size
.constant
))
5575 sibcall_failure
= 1;
5577 /* Don't allow anything left on stack from computation
5578 of argument to alloca. */
5579 if (flags
& ECF_MAY_BE_ALLOCA
)
5580 do_pending_stack_adjust ();
5582 if (arg
->value
== arg
->stack
)
5583 /* If the value is already in the stack slot, we are done. */
5585 else if (arg
->mode
!= BLKmode
)
5587 unsigned int parm_align
;
5589 /* Argument is a scalar, not entirely passed in registers.
5590 (If part is passed in registers, arg->partial says how much
5591 and emit_push_insn will take care of putting it there.)
5593 Push it, and if its size is less than the
5594 amount of space allocated to it,
5595 also bump stack pointer by the additional space.
5596 Note that in C the default argument promotions
5597 will prevent such mismatches. */
5599 poly_int64 size
= (TYPE_EMPTY_P (TREE_TYPE (pval
))
5600 ? 0 : GET_MODE_SIZE (arg
->mode
));
5602 /* Compute how much space the push instruction will push.
5603 On many machines, pushing a byte will advance the stack
5604 pointer by a halfword. */
5605 #ifdef PUSH_ROUNDING
5606 size
= PUSH_ROUNDING (size
);
5610 /* Compute how much space the argument should get:
5611 round up to a multiple of the alignment for arguments. */
5612 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5614 /* At the moment we don't (need to) support ABIs for which the
5615 padding isn't known at compile time. In principle it should
5616 be easy to add though. */
5617 used
= force_align_up (size
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
5619 /* Compute the alignment of the pushed argument. */
5620 parm_align
= arg
->locate
.boundary
;
5621 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5624 poly_int64 pad
= used
- size
;
5625 unsigned int pad_align
= known_alignment (pad
) * BITS_PER_UNIT
;
5627 parm_align
= MIN (parm_align
, pad_align
);
5630 /* This isn't already where we want it on the stack, so put it there.
5631 This can either be done with push or copy insns. */
5632 if (maybe_ne (used
, 0)
5633 && !emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
),
5634 NULL_RTX
, parm_align
, partial
, reg
, used
- size
,
5635 argblock
, ARGS_SIZE_RTX (arg
->locate
.offset
),
5636 reg_parm_stack_space
,
5637 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
), true))
5638 sibcall_failure
= 1;
5640 /* Unless this is a partially-in-register argument, the argument is now
5643 arg
->value
= arg
->stack
;
5647 /* BLKmode, at least partly to be pushed. */
5649 unsigned int parm_align
;
5653 /* Pushing a nonscalar.
5654 If part is passed in registers, PARTIAL says how much
5655 and emit_push_insn will take care of putting it there. */
5657 /* Round its size up to a multiple
5658 of the allocation unit for arguments. */
5660 if (arg
->locate
.size
.var
!= 0)
5663 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
5667 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
5668 for BLKmode is careful to avoid it. */
5669 excess
= (arg
->locate
.size
.constant
5670 - arg_int_size_in_bytes (TREE_TYPE (pval
))
5672 size_rtx
= expand_expr (arg_size_in_bytes (TREE_TYPE (pval
)),
5673 NULL_RTX
, TYPE_MODE (sizetype
),
5677 parm_align
= arg
->locate
.boundary
;
5679 /* When an argument is padded down, the block is aligned to
5680 PARM_BOUNDARY, but the actual argument isn't. */
5681 if (targetm
.calls
.function_arg_padding (arg
->mode
, TREE_TYPE (pval
))
5684 if (arg
->locate
.size
.var
)
5685 parm_align
= BITS_PER_UNIT
;
5688 unsigned int excess_align
5689 = known_alignment (excess
) * BITS_PER_UNIT
;
5690 if (excess_align
!= 0)
5691 parm_align
= MIN (parm_align
, excess_align
);
5695 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
5697 /* emit_push_insn might not work properly if arg->value and
5698 argblock + arg->locate.offset areas overlap. */
5702 if (strip_offset (XEXP (x
, 0), &i
)
5703 == crtl
->args
.internal_arg_pointer
)
5705 /* arg.locate doesn't contain the pretend_args_size offset,
5706 it's part of argblock. Ensure we don't count it in I. */
5707 if (STACK_GROWS_DOWNWARD
)
5708 i
-= crtl
->args
.pretend_args_size
;
5710 i
+= crtl
->args
.pretend_args_size
;
5712 /* expand_call should ensure this. */
5713 gcc_assert (!arg
->locate
.offset
.var
5714 && arg
->locate
.size
.var
== 0);
5715 poly_int64 size_val
= rtx_to_poly_int64 (size_rtx
);
5717 if (known_eq (arg
->locate
.offset
.constant
, i
))
5719 /* Even though they appear to be at the same location,
5720 if part of the outgoing argument is in registers,
5721 they aren't really at the same location. Check for
5722 this by making sure that the incoming size is the
5723 same as the outgoing size. */
5724 if (maybe_ne (arg
->locate
.size
.constant
, size_val
))
5725 sibcall_failure
= 1;
5727 else if (maybe_in_range_p (arg
->locate
.offset
.constant
,
5729 sibcall_failure
= 1;
5730 /* Use arg->locate.size.constant instead of size_rtx
5731 because we only care about the part of the argument
5733 else if (maybe_in_range_p (i
, arg
->locate
.offset
.constant
,
5734 arg
->locate
.size
.constant
))
5735 sibcall_failure
= 1;
5739 if (!CONST_INT_P (size_rtx
) || INTVAL (size_rtx
) != 0)
5740 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
5741 parm_align
, partial
, reg
, excess
, argblock
,
5742 ARGS_SIZE_RTX (arg
->locate
.offset
),
5743 reg_parm_stack_space
,
5744 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
), false);
5746 /* Unless this is a partially-in-register argument, the argument is now
5749 ??? Unlike the case above, in which we want the actual
5750 address of the data, so that we can load it directly into a
5751 register, here we want the address of the stack slot, so that
5752 it's properly aligned for word-by-word copying or something
5753 like that. It's not clear that this is always correct. */
5755 arg
->value
= arg
->stack_slot
;
5758 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
5760 tree type
= TREE_TYPE (arg
->tree_value
);
5762 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
5763 int_size_in_bytes (type
));
5766 /* Mark all slots this store used. */
5767 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
5768 && argblock
&& ! variable_size
&& arg
->stack
)
5769 mark_stack_region_used (lower_bound
, upper_bound
);
5771 /* Once we have pushed something, pops can't safely
5772 be deferred during the rest of the arguments. */
5775 /* Free any temporary slots made in processing this argument. */
5778 return sibcall_failure
;
5781 /* Nonzero if we do not know how to pass TYPE solely in registers. */
5784 must_pass_in_stack_var_size (machine_mode mode ATTRIBUTE_UNUSED
,
5790 /* If the type has variable size... */
5791 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
5794 /* If the type is marked as addressable (it is required
5795 to be constructed into the stack)... */
5796 if (TREE_ADDRESSABLE (type
))
5802 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5803 takes trailing padding of a structure into account. */
5804 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5807 must_pass_in_stack_var_size_or_pad (machine_mode mode
, const_tree type
)
5812 /* If the type has variable size... */
5813 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
5816 /* If the type is marked as addressable (it is required
5817 to be constructed into the stack)... */
5818 if (TREE_ADDRESSABLE (type
))
5821 if (TYPE_EMPTY_P (type
))
5824 /* If the padding and mode of the type is such that a copy into
5825 a register would put it into the wrong part of the register. */
5827 && int_size_in_bytes (type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
5828 && (targetm
.calls
.function_arg_padding (mode
, type
)
5829 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
5835 /* Tell the garbage collector about GTY markers in this source file. */
5836 #include "gt-calls.h"