1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
24 #include "coretypes.h"
35 #include "diagnostic-core.h"
40 #include "langhooks.h"
46 #include "tree-flow.h"
48 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
49 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
51 /* Data structure and subroutines used within expand_call. */
55 /* Tree node for this argument. */
57 /* Mode for value; TYPE_MODE unless promoted. */
58 enum machine_mode mode
;
59 /* Current RTL value for argument, or 0 if it isn't precomputed. */
61 /* Initially-compute RTL value for argument; only for const functions. */
63 /* Register to pass this argument in, 0 if passed on stack, or an
64 PARALLEL if the arg is to be copied into multiple non-contiguous
67 /* Register to pass this argument in when generating tail call sequence.
68 This is not the same register as for normal calls on machines with
71 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
72 form for emit_group_move. */
74 /* If REG was promoted from the actual mode of the argument expression,
75 indicates whether the promotion is sign- or zero-extended. */
77 /* Number of bytes to put in registers. 0 means put the whole arg
78 in registers. Also 0 if not passed in registers. */
80 /* Nonzero if argument must be passed on stack.
81 Note that some arguments may be passed on the stack
82 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
83 pass_on_stack identifies arguments that *cannot* go in registers. */
85 /* Some fields packaged up for locate_and_pad_parm. */
86 struct locate_and_pad_arg_data locate
;
87 /* Location on the stack at which parameter should be stored. The store
88 has already been done if STACK == VALUE. */
90 /* Location on the stack of the start of this argument slot. This can
91 differ from STACK if this arg pads downward. This location is known
92 to be aligned to FUNCTION_ARG_BOUNDARY. */
94 /* Place that this stack area has been saved, if needed. */
96 /* If an argument's alignment does not permit direct copying into registers,
97 copy in smaller-sized pieces into pseudos. These are stored in a
98 block pointed to by this field. The next field says how many
99 word-sized pseudos we made. */
104 /* A vector of one char per byte of stack space. A byte if nonzero if
105 the corresponding stack location has been used.
106 This vector is used to prevent a function call within an argument from
107 clobbering any stack already set up. */
108 static char *stack_usage_map
;
110 /* Size of STACK_USAGE_MAP. */
111 static int highest_outgoing_arg_in_use
;
113 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
114 stack location's tail call argument has been already stored into the stack.
115 This bitmap is used to prevent sibling call optimization if function tries
116 to use parent's incoming argument slots when they have been already
117 overwritten with tail call arguments. */
118 static sbitmap stored_args_map
;
120 /* stack_arg_under_construction is nonzero when an argument may be
121 initialized with a constructor call (including a C function that
122 returns a BLKmode struct) and expand_call must take special action
123 to make sure the object being constructed does not overlap the
124 argument list for the constructor call. */
125 static int stack_arg_under_construction
;
127 static void emit_call_1 (rtx
, tree
, tree
, tree
, HOST_WIDE_INT
, HOST_WIDE_INT
,
128 HOST_WIDE_INT
, rtx
, rtx
, int, rtx
, int,
130 static void precompute_register_parameters (int, struct arg_data
*, int *);
131 static int store_one_arg (struct arg_data
*, rtx
, int, int, int);
132 static void store_unaligned_arguments_into_pseudos (struct arg_data
*, int);
133 static int finalize_must_preallocate (int, int, struct arg_data
*,
135 static void precompute_arguments (int, struct arg_data
*);
136 static int compute_argument_block_size (int, struct args_size
*, tree
, tree
, int);
137 static void initialize_argument_information (int, struct arg_data
*,
138 struct args_size
*, int,
140 tree
, tree
, CUMULATIVE_ARGS
*, int,
141 rtx
*, int *, int *, int *,
143 static void compute_argument_addresses (struct arg_data
*, rtx
, int);
144 static rtx
rtx_for_function_call (tree
, tree
);
145 static void load_register_parameters (struct arg_data
*, int, rtx
*, int,
147 static rtx
emit_library_call_value_1 (int, rtx
, rtx
, enum libcall_type
,
148 enum machine_mode
, int, va_list);
149 static int special_function_p (const_tree
, int);
150 static int check_sibcall_argument_overlap_1 (rtx
);
151 static int check_sibcall_argument_overlap (rtx
, struct arg_data
*, int);
153 static int combine_pending_stack_adjustment_and_call (int, struct args_size
*,
155 static tree
split_complex_types (tree
);
157 #ifdef REG_PARM_STACK_SPACE
158 static rtx
save_fixed_argument_area (int, rtx
, int *, int *);
159 static void restore_fixed_argument_area (rtx
, rtx
, int, int);
162 /* Force FUNEXP into a form suitable for the address of a CALL,
163 and return that as an rtx. Also load the static chain register
164 if FNDECL is a nested function.
166 CALL_FUSAGE points to a variable holding the prospective
167 CALL_INSN_FUNCTION_USAGE information. */
170 prepare_call_address (tree fndecl
, rtx funexp
, rtx static_chain_value
,
171 rtx
*call_fusage
, int reg_parm_seen
, int sibcallp
)
173 /* Make a valid memory address and copy constants through pseudo-regs,
174 but not for a constant address if -fno-function-cse. */
175 if (GET_CODE (funexp
) != SYMBOL_REF
)
176 /* If we are using registers for parameters, force the
177 function address into a register now. */
178 funexp
= ((reg_parm_seen
179 && targetm
.small_register_classes_for_mode_p (FUNCTION_MODE
))
180 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
181 : memory_address (FUNCTION_MODE
, funexp
));
184 #ifndef NO_FUNCTION_CSE
185 if (optimize
&& ! flag_no_function_cse
)
186 funexp
= force_reg (Pmode
, funexp
);
190 if (static_chain_value
!= 0)
195 chain
= targetm
.calls
.static_chain (fndecl
, false);
196 static_chain_value
= convert_memory_address (Pmode
, static_chain_value
);
198 emit_move_insn (chain
, static_chain_value
);
200 use_reg (call_fusage
, chain
);
206 /* Generate instructions to call function FUNEXP,
207 and optionally pop the results.
208 The CALL_INSN is the first insn generated.
210 FNDECL is the declaration node of the function. This is given to the
211 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
214 FUNTYPE is the data type of the function. This is given to the hook
215 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
216 own args. We used to allow an identifier for library functions, but
217 that doesn't work when the return type is an aggregate type and the
218 calling convention says that the pointer to this aggregate is to be
219 popped by the callee.
221 STACK_SIZE is the number of bytes of arguments on the stack,
222 ROUNDED_STACK_SIZE is that number rounded up to
223 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
224 both to put into the call insn and to generate explicit popping
227 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
228 It is zero if this call doesn't want a structure value.
230 NEXT_ARG_REG is the rtx that results from executing
231 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
232 just after all the args have had their registers assigned.
233 This could be whatever you like, but normally it is the first
234 arg-register beyond those used for args in this call,
235 or 0 if all the arg-registers are used in this call.
236 It is passed on to `gen_call' so you can put this info in the call insn.
238 VALREG is a hard register in which a value is returned,
239 or 0 if the call does not return a value.
241 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
242 the args to this call were processed.
243 We restore `inhibit_defer_pop' to that value.
245 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
246 denote registers used by the called function. */
249 emit_call_1 (rtx funexp
, tree fntree ATTRIBUTE_UNUSED
, tree fndecl ATTRIBUTE_UNUSED
,
250 tree funtype ATTRIBUTE_UNUSED
,
251 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED
,
252 HOST_WIDE_INT rounded_stack_size
,
253 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED
,
254 rtx next_arg_reg ATTRIBUTE_UNUSED
, rtx valreg
,
255 int old_inhibit_defer_pop
, rtx call_fusage
, int ecf_flags
,
256 CUMULATIVE_ARGS
*args_so_far ATTRIBUTE_UNUSED
)
258 rtx rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
260 int already_popped
= 0;
261 HOST_WIDE_INT n_popped
262 = targetm
.calls
.return_pops_args (fndecl
, funtype
, stack_size
);
264 #ifdef CALL_POPS_ARGS
265 n_popped
+= CALL_POPS_ARGS (* args_so_far
);
268 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
269 and we don't want to load it into a register as an optimization,
270 because prepare_call_address already did it if it should be done. */
271 if (GET_CODE (funexp
) != SYMBOL_REF
)
272 funexp
= memory_address (FUNCTION_MODE
, funexp
);
274 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
275 if ((ecf_flags
& ECF_SIBCALL
)
276 && HAVE_sibcall_pop
&& HAVE_sibcall_value_pop
277 && (n_popped
> 0 || stack_size
== 0))
279 rtx n_pop
= GEN_INT (n_popped
);
282 /* If this subroutine pops its own args, record that in the call insn
283 if possible, for the sake of frame pointer elimination. */
286 pat
= GEN_SIBCALL_VALUE_POP (valreg
,
287 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
288 rounded_stack_size_rtx
, next_arg_reg
,
291 pat
= GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
292 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
294 emit_call_insn (pat
);
300 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
301 /* If the target has "call" or "call_value" insns, then prefer them
302 if no arguments are actually popped. If the target does not have
303 "call" or "call_value" insns, then we must use the popping versions
304 even if the call has no arguments to pop. */
305 #if defined (HAVE_call) && defined (HAVE_call_value)
306 if (HAVE_call
&& HAVE_call_value
&& HAVE_call_pop
&& HAVE_call_value_pop
309 if (HAVE_call_pop
&& HAVE_call_value_pop
)
312 rtx n_pop
= GEN_INT (n_popped
);
315 /* If this subroutine pops its own args, record that in the call insn
316 if possible, for the sake of frame pointer elimination. */
319 pat
= GEN_CALL_VALUE_POP (valreg
,
320 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
321 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
323 pat
= GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
324 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
326 emit_call_insn (pat
);
332 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
333 if ((ecf_flags
& ECF_SIBCALL
)
334 && HAVE_sibcall
&& HAVE_sibcall_value
)
337 emit_call_insn (GEN_SIBCALL_VALUE (valreg
,
338 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
339 rounded_stack_size_rtx
,
340 next_arg_reg
, NULL_RTX
));
342 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
343 rounded_stack_size_rtx
, next_arg_reg
,
344 GEN_INT (struct_value_size
)));
349 #if defined (HAVE_call) && defined (HAVE_call_value)
350 if (HAVE_call
&& HAVE_call_value
)
353 emit_call_insn (GEN_CALL_VALUE (valreg
,
354 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
355 rounded_stack_size_rtx
, next_arg_reg
,
358 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
359 rounded_stack_size_rtx
, next_arg_reg
,
360 GEN_INT (struct_value_size
)));
366 /* Find the call we just emitted. */
367 call_insn
= last_call_insn ();
369 /* Put the register usage information there. */
370 add_function_usage_to (call_insn
, call_fusage
);
372 /* If this is a const call, then set the insn's unchanging bit. */
373 if (ecf_flags
& ECF_CONST
)
374 RTL_CONST_CALL_P (call_insn
) = 1;
376 /* If this is a pure call, then set the insn's unchanging bit. */
377 if (ecf_flags
& ECF_PURE
)
378 RTL_PURE_CALL_P (call_insn
) = 1;
380 /* If this is a const call, then set the insn's unchanging bit. */
381 if (ecf_flags
& ECF_LOOPING_CONST_OR_PURE
)
382 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn
) = 1;
384 /* Create a nothrow REG_EH_REGION note, if needed. */
385 make_reg_eh_region_note (call_insn
, ecf_flags
, 0);
387 if (ecf_flags
& ECF_NORETURN
)
388 add_reg_note (call_insn
, REG_NORETURN
, const0_rtx
);
390 if (ecf_flags
& ECF_RETURNS_TWICE
)
392 add_reg_note (call_insn
, REG_SETJMP
, const0_rtx
);
393 cfun
->calls_setjmp
= 1;
396 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
398 /* Record debug information for virtual calls. */
399 if (flag_enable_icf_debug
&& fndecl
== NULL
)
400 (*debug_hooks
->virtual_call_token
) (CALL_EXPR_FN (fntree
),
401 INSN_UID (call_insn
));
403 /* Restore this now, so that we do defer pops for this call's args
404 if the context of the call as a whole permits. */
405 inhibit_defer_pop
= old_inhibit_defer_pop
;
410 CALL_INSN_FUNCTION_USAGE (call_insn
)
411 = gen_rtx_EXPR_LIST (VOIDmode
,
412 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
413 CALL_INSN_FUNCTION_USAGE (call_insn
));
414 rounded_stack_size
-= n_popped
;
415 rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
416 stack_pointer_delta
-= n_popped
;
418 /* If popup is needed, stack realign must use DRAP */
419 if (SUPPORTS_STACK_ALIGNMENT
)
420 crtl
->need_drap
= true;
423 if (!ACCUMULATE_OUTGOING_ARGS
)
425 /* If returning from the subroutine does not automatically pop the args,
426 we need an instruction to pop them sooner or later.
427 Perhaps do it now; perhaps just record how much space to pop later.
429 If returning from the subroutine does pop the args, indicate that the
430 stack pointer will be changed. */
432 if (rounded_stack_size
!= 0)
434 if (ecf_flags
& ECF_NORETURN
)
435 /* Just pretend we did the pop. */
436 stack_pointer_delta
-= rounded_stack_size
;
437 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
438 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
439 pending_stack_adjust
+= rounded_stack_size
;
441 adjust_stack (rounded_stack_size_rtx
);
444 /* When we accumulate outgoing args, we must avoid any stack manipulations.
445 Restore the stack pointer to its original value now. Usually
446 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
447 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
448 popping variants of functions exist as well.
450 ??? We may optimize similar to defer_pop above, but it is
451 probably not worthwhile.
453 ??? It will be worthwhile to enable combine_stack_adjustments even for
456 anti_adjust_stack (GEN_INT (n_popped
));
459 /* Determine if the function identified by NAME and FNDECL is one with
460 special properties we wish to know about.
462 For example, if the function might return more than one time (setjmp), then
463 set RETURNS_TWICE to a nonzero value.
465 Similarly set NORETURN if the function is in the longjmp family.
467 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
468 space from the stack such as alloca. */
471 special_function_p (const_tree fndecl
, int flags
)
473 if (fndecl
&& DECL_NAME (fndecl
)
474 && IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) <= 17
475 /* Exclude functions not at the file scope, or not `extern',
476 since they are not the magic functions we would otherwise
478 FIXME: this should be handled with attributes, not with this
479 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
480 because you can declare fork() inside a function if you
482 && (DECL_CONTEXT (fndecl
) == NULL_TREE
483 || TREE_CODE (DECL_CONTEXT (fndecl
)) == TRANSLATION_UNIT_DECL
)
484 && TREE_PUBLIC (fndecl
))
486 const char *name
= IDENTIFIER_POINTER (DECL_NAME (fndecl
));
487 const char *tname
= name
;
489 /* We assume that alloca will always be called by name. It
490 makes no sense to pass it as a pointer-to-function to
491 anything that does not understand its behavior. */
492 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 6
494 && ! strcmp (name
, "alloca"))
495 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 16
497 && ! strcmp (name
, "__builtin_alloca"))))
498 flags
|= ECF_MAY_BE_ALLOCA
;
500 /* Disregard prefix _, __, __x or __builtin_. */
505 && !strncmp (name
+ 3, "uiltin_", 7))
507 else if (name
[1] == '_' && name
[2] == 'x')
509 else if (name
[1] == '_')
518 && (! strcmp (tname
, "setjmp")
519 || ! strcmp (tname
, "setjmp_syscall")))
521 && ! strcmp (tname
, "sigsetjmp"))
523 && ! strcmp (tname
, "savectx")))
524 flags
|= ECF_RETURNS_TWICE
;
527 && ! strcmp (tname
, "siglongjmp"))
528 flags
|= ECF_NORETURN
;
530 else if ((tname
[0] == 'q' && tname
[1] == 's'
531 && ! strcmp (tname
, "qsetjmp"))
532 || (tname
[0] == 'v' && tname
[1] == 'f'
533 && ! strcmp (tname
, "vfork"))
534 || (tname
[0] == 'g' && tname
[1] == 'e'
535 && !strcmp (tname
, "getcontext")))
536 flags
|= ECF_RETURNS_TWICE
;
538 else if (tname
[0] == 'l' && tname
[1] == 'o'
539 && ! strcmp (tname
, "longjmp"))
540 flags
|= ECF_NORETURN
;
546 /* Return nonzero when FNDECL represents a call to setjmp. */
549 setjmp_call_p (const_tree fndecl
)
551 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
555 /* Return true if STMT is an alloca call. */
558 gimple_alloca_call_p (const_gimple stmt
)
562 if (!is_gimple_call (stmt
))
565 fndecl
= gimple_call_fndecl (stmt
);
566 if (fndecl
&& (special_function_p (fndecl
, 0) & ECF_MAY_BE_ALLOCA
))
572 /* Return true when exp contains alloca call. */
575 alloca_call_p (const_tree exp
)
577 if (TREE_CODE (exp
) == CALL_EXPR
578 && TREE_CODE (CALL_EXPR_FN (exp
)) == ADDR_EXPR
579 && (TREE_CODE (TREE_OPERAND (CALL_EXPR_FN (exp
), 0)) == FUNCTION_DECL
)
580 && (special_function_p (TREE_OPERAND (CALL_EXPR_FN (exp
), 0), 0)
581 & ECF_MAY_BE_ALLOCA
))
586 /* Detect flags (function attributes) from the function decl or type node. */
589 flags_from_decl_or_type (const_tree exp
)
595 /* The function exp may have the `malloc' attribute. */
596 if (DECL_IS_MALLOC (exp
))
599 /* The function exp may have the `returns_twice' attribute. */
600 if (DECL_IS_RETURNS_TWICE (exp
))
601 flags
|= ECF_RETURNS_TWICE
;
603 /* Process the pure and const attributes. */
604 if (TREE_READONLY (exp
))
606 if (DECL_PURE_P (exp
))
608 if (DECL_LOOPING_CONST_OR_PURE_P (exp
))
609 flags
|= ECF_LOOPING_CONST_OR_PURE
;
611 if (DECL_IS_NOVOPS (exp
))
613 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp
)))
616 if (TREE_NOTHROW (exp
))
617 flags
|= ECF_NOTHROW
;
619 flags
= special_function_p (exp
, flags
);
621 else if (TYPE_P (exp
) && TYPE_READONLY (exp
))
624 if (TREE_THIS_VOLATILE (exp
))
626 flags
|= ECF_NORETURN
;
627 if (flags
& (ECF_CONST
|ECF_PURE
))
628 flags
|= ECF_LOOPING_CONST_OR_PURE
;
634 /* Detect flags from a CALL_EXPR. */
637 call_expr_flags (const_tree t
)
640 tree decl
= get_callee_fndecl (t
);
643 flags
= flags_from_decl_or_type (decl
);
646 t
= TREE_TYPE (CALL_EXPR_FN (t
));
647 if (t
&& TREE_CODE (t
) == POINTER_TYPE
)
648 flags
= flags_from_decl_or_type (TREE_TYPE (t
));
656 /* Precompute all register parameters as described by ARGS, storing values
657 into fields within the ARGS array.
659 NUM_ACTUALS indicates the total number elements in the ARGS array.
661 Set REG_PARM_SEEN if we encounter a register parameter. */
664 precompute_register_parameters (int num_actuals
, struct arg_data
*args
,
671 for (i
= 0; i
< num_actuals
; i
++)
672 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
676 if (args
[i
].value
== 0)
679 args
[i
].value
= expand_normal (args
[i
].tree_value
);
680 preserve_temp_slots (args
[i
].value
);
684 /* If the value is a non-legitimate constant, force it into a
685 pseudo now. TLS symbols sometimes need a call to resolve. */
686 if (CONSTANT_P (args
[i
].value
)
687 && !LEGITIMATE_CONSTANT_P (args
[i
].value
))
688 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
690 /* If we are to promote the function arg to a wider mode,
693 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
695 = convert_modes (args
[i
].mode
,
696 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
697 args
[i
].value
, args
[i
].unsignedp
);
699 /* If we're going to have to load the value by parts, pull the
700 parts into pseudos. The part extraction process can involve
701 non-trivial computation. */
702 if (GET_CODE (args
[i
].reg
) == PARALLEL
)
704 tree type
= TREE_TYPE (args
[i
].tree_value
);
705 args
[i
].parallel_value
706 = emit_group_load_into_temps (args
[i
].reg
, args
[i
].value
,
707 type
, int_size_in_bytes (type
));
710 /* If the value is expensive, and we are inside an appropriately
711 short loop, put the value into a pseudo and then put the pseudo
714 For small register classes, also do this if this call uses
715 register parameters. This is to avoid reload conflicts while
716 loading the parameters registers. */
718 else if ((! (REG_P (args
[i
].value
)
719 || (GET_CODE (args
[i
].value
) == SUBREG
720 && REG_P (SUBREG_REG (args
[i
].value
)))))
721 && args
[i
].mode
!= BLKmode
722 && rtx_cost (args
[i
].value
, SET
, optimize_insn_for_speed_p ())
725 && targetm
.small_register_classes_for_mode_p (args
[i
].mode
))
727 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
731 #ifdef REG_PARM_STACK_SPACE
733 /* The argument list is the property of the called routine and it
734 may clobber it. If the fixed area has been used for previous
735 parameters, we must save and restore it. */
738 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
743 /* Compute the boundary of the area that needs to be saved, if any. */
744 high
= reg_parm_stack_space
;
745 #ifdef ARGS_GROW_DOWNWARD
748 if (high
> highest_outgoing_arg_in_use
)
749 high
= highest_outgoing_arg_in_use
;
751 for (low
= 0; low
< high
; low
++)
752 if (stack_usage_map
[low
] != 0)
755 enum machine_mode save_mode
;
760 while (stack_usage_map
[--high
] == 0)
764 *high_to_save
= high
;
766 num_to_save
= high
- low
+ 1;
767 save_mode
= mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
769 /* If we don't have the required alignment, must do this
771 if ((low
& (MIN (GET_MODE_SIZE (save_mode
),
772 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
775 #ifdef ARGS_GROW_DOWNWARD
780 stack_area
= gen_rtx_MEM (save_mode
,
781 memory_address (save_mode
,
782 plus_constant (argblock
,
785 set_mem_align (stack_area
, PARM_BOUNDARY
);
786 if (save_mode
== BLKmode
)
788 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
789 emit_block_move (validize_mem (save_area
), stack_area
,
790 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
794 save_area
= gen_reg_rtx (save_mode
);
795 emit_move_insn (save_area
, stack_area
);
805 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
807 enum machine_mode save_mode
= GET_MODE (save_area
);
811 #ifdef ARGS_GROW_DOWNWARD
812 delta
= -high_to_save
;
816 stack_area
= gen_rtx_MEM (save_mode
,
817 memory_address (save_mode
,
818 plus_constant (argblock
, delta
)));
819 set_mem_align (stack_area
, PARM_BOUNDARY
);
821 if (save_mode
!= BLKmode
)
822 emit_move_insn (stack_area
, save_area
);
824 emit_block_move (stack_area
, validize_mem (save_area
),
825 GEN_INT (high_to_save
- low_to_save
+ 1),
828 #endif /* REG_PARM_STACK_SPACE */
830 /* If any elements in ARGS refer to parameters that are to be passed in
831 registers, but not in memory, and whose alignment does not permit a
832 direct copy into registers. Copy the values into a group of pseudos
833 which we will later copy into the appropriate hard registers.
835 Pseudos for each unaligned argument will be stored into the array
836 args[argnum].aligned_regs. The caller is responsible for deallocating
837 the aligned_regs array if it is nonzero. */
840 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
844 for (i
= 0; i
< num_actuals
; i
++)
845 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
846 && args
[i
].mode
== BLKmode
847 && MEM_P (args
[i
].value
)
848 && (MEM_ALIGN (args
[i
].value
)
849 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
851 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
852 int endian_correction
= 0;
856 gcc_assert (args
[i
].partial
% UNITS_PER_WORD
== 0);
857 args
[i
].n_aligned_regs
= args
[i
].partial
/ UNITS_PER_WORD
;
861 args
[i
].n_aligned_regs
862 = (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
865 args
[i
].aligned_regs
= XNEWVEC (rtx
, args
[i
].n_aligned_regs
);
867 /* Structures smaller than a word are normally aligned to the
868 least significant byte. On a BYTES_BIG_ENDIAN machine,
869 this means we must skip the empty high order bytes when
870 calculating the bit offset. */
871 if (bytes
< UNITS_PER_WORD
872 #ifdef BLOCK_REG_PADDING
873 && (BLOCK_REG_PADDING (args
[i
].mode
,
874 TREE_TYPE (args
[i
].tree_value
), 1)
880 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
882 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
884 rtx reg
= gen_reg_rtx (word_mode
);
885 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
886 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
888 args
[i
].aligned_regs
[j
] = reg
;
889 word
= extract_bit_field (word
, bitsize
, 0, 1, false, NULL_RTX
,
890 word_mode
, word_mode
);
892 /* There is no need to restrict this code to loading items
893 in TYPE_ALIGN sized hunks. The bitfield instructions can
894 load up entire word sized registers efficiently.
896 ??? This may not be needed anymore.
897 We use to emit a clobber here but that doesn't let later
898 passes optimize the instructions we emit. By storing 0 into
899 the register later passes know the first AND to zero out the
900 bitfield being set in the register is unnecessary. The store
901 of 0 will be deleted as will at least the first AND. */
903 emit_move_insn (reg
, const0_rtx
);
905 bytes
-= bitsize
/ BITS_PER_UNIT
;
906 store_bit_field (reg
, bitsize
, endian_correction
, word_mode
,
912 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
915 NUM_ACTUALS is the total number of parameters.
917 N_NAMED_ARGS is the total number of named arguments.
919 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
922 FNDECL is the tree code for the target of this call (if known)
924 ARGS_SO_FAR holds state needed by the target to know where to place
927 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
928 for arguments which are passed in registers.
930 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
931 and may be modified by this routine.
933 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
934 flags which may may be modified by this routine.
936 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
937 that requires allocation of stack space.
939 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
940 the thunked-to function. */
943 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
944 struct arg_data
*args
,
945 struct args_size
*args_size
,
946 int n_named_args ATTRIBUTE_UNUSED
,
947 tree exp
, tree struct_value_addr_value
,
948 tree fndecl
, tree fntype
,
949 CUMULATIVE_ARGS
*args_so_far
,
950 int reg_parm_stack_space
,
951 rtx
*old_stack_level
, int *old_pending_adj
,
952 int *must_preallocate
, int *ecf_flags
,
953 bool *may_tailcall
, bool call_from_thunk_p
)
955 location_t loc
= EXPR_LOCATION (exp
);
956 /* 1 if scanning parms front to back, -1 if scanning back to front. */
959 /* Count arg position in order args appear. */
964 args_size
->constant
= 0;
967 /* In this loop, we consider args in the order they are written.
968 We fill up ARGS from the front or from the back if necessary
969 so that in any case the first arg to be pushed ends up at the front. */
971 if (PUSH_ARGS_REVERSED
)
973 i
= num_actuals
- 1, inc
= -1;
974 /* In this case, must reverse order of args
975 so that we compute and push the last arg first. */
982 /* First fill in the actual arguments in the ARGS array, splitting
983 complex arguments if necessary. */
986 call_expr_arg_iterator iter
;
989 if (struct_value_addr_value
)
991 args
[j
].tree_value
= struct_value_addr_value
;
994 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
996 tree argtype
= TREE_TYPE (arg
);
997 if (targetm
.calls
.split_complex_arg
999 && TREE_CODE (argtype
) == COMPLEX_TYPE
1000 && targetm
.calls
.split_complex_arg (argtype
))
1002 tree subtype
= TREE_TYPE (argtype
);
1003 args
[j
].tree_value
= build1 (REALPART_EXPR
, subtype
, arg
);
1005 args
[j
].tree_value
= build1 (IMAGPART_EXPR
, subtype
, arg
);
1008 args
[j
].tree_value
= arg
;
1013 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1014 for (argpos
= 0; argpos
< num_actuals
; i
+= inc
, argpos
++)
1016 tree type
= TREE_TYPE (args
[i
].tree_value
);
1018 enum machine_mode mode
;
1020 /* Replace erroneous argument with constant zero. */
1021 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1022 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1024 /* If TYPE is a transparent union or record, pass things the way
1025 we would pass the first field of the union or record. We have
1026 already verified that the modes are the same. */
1027 if ((TREE_CODE (type
) == UNION_TYPE
|| TREE_CODE (type
) == RECORD_TYPE
)
1028 && TYPE_TRANSPARENT_AGGR (type
))
1029 type
= TREE_TYPE (first_field (type
));
1031 /* Decide where to pass this arg.
1033 args[i].reg is nonzero if all or part is passed in registers.
1035 args[i].partial is nonzero if part but not all is passed in registers,
1036 and the exact value says how many bytes are passed in registers.
1038 args[i].pass_on_stack is nonzero if the argument must at least be
1039 computed on the stack. It may then be loaded back into registers
1040 if args[i].reg is nonzero.
1042 These decisions are driven by the FUNCTION_... macros and must agree
1043 with those made by function.c. */
1045 /* See if this argument should be passed by invisible reference. */
1046 if (pass_by_reference (args_so_far
, TYPE_MODE (type
),
1047 type
, argpos
< n_named_args
))
1053 = reference_callee_copied (args_so_far
, TYPE_MODE (type
),
1054 type
, argpos
< n_named_args
);
1056 /* If we're compiling a thunk, pass through invisible references
1057 instead of making a copy. */
1058 if (call_from_thunk_p
1060 && !TREE_ADDRESSABLE (type
)
1061 && (base
= get_base_address (args
[i
].tree_value
))
1062 && TREE_CODE (base
) != SSA_NAME
1063 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
)))))
1065 /* We can't use sibcalls if a callee-copied argument is
1066 stored in the current function's frame. */
1067 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
1068 *may_tailcall
= false;
1070 args
[i
].tree_value
= build_fold_addr_expr_loc (loc
,
1071 args
[i
].tree_value
);
1072 type
= TREE_TYPE (args
[i
].tree_value
);
1074 if (*ecf_flags
& ECF_CONST
)
1075 *ecf_flags
&= ~(ECF_CONST
| ECF_LOOPING_CONST_OR_PURE
);
1079 /* We make a copy of the object and pass the address to the
1080 function being called. */
1083 if (!COMPLETE_TYPE_P (type
)
1084 || TREE_CODE (TYPE_SIZE_UNIT (type
)) != INTEGER_CST
1085 || (flag_stack_check
== GENERIC_STACK_CHECK
1086 && compare_tree_int (TYPE_SIZE_UNIT (type
),
1087 STACK_CHECK_MAX_VAR_SIZE
) > 0))
1089 /* This is a variable-sized object. Make space on the stack
1091 rtx size_rtx
= expr_size (args
[i
].tree_value
);
1093 if (*old_stack_level
== 0)
1095 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1096 *old_pending_adj
= pending_stack_adjust
;
1097 pending_stack_adjust
= 0;
1100 /* We can pass TRUE as the 4th argument because we just
1101 saved the stack pointer and will restore it right after
1103 copy
= allocate_dynamic_stack_space (size_rtx
,
1107 copy
= gen_rtx_MEM (BLKmode
, copy
);
1108 set_mem_attributes (copy
, type
, 1);
1111 copy
= assign_temp (type
, 0, 1, 0);
1113 store_expr (args
[i
].tree_value
, copy
, 0, false);
1115 /* Just change the const function to pure and then let
1116 the next test clear the pure based on
1118 if (*ecf_flags
& ECF_CONST
)
1120 *ecf_flags
&= ~ECF_CONST
;
1121 *ecf_flags
|= ECF_PURE
;
1124 if (!callee_copies
&& *ecf_flags
& ECF_PURE
)
1125 *ecf_flags
&= ~(ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
1128 = build_fold_addr_expr_loc (loc
, make_tree (type
, copy
));
1129 type
= TREE_TYPE (args
[i
].tree_value
);
1130 *may_tailcall
= false;
1134 unsignedp
= TYPE_UNSIGNED (type
);
1135 mode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
1136 fndecl
? TREE_TYPE (fndecl
) : fntype
, 0);
1138 args
[i
].unsignedp
= unsignedp
;
1139 args
[i
].mode
= mode
;
1141 args
[i
].reg
= targetm
.calls
.function_arg (args_so_far
, mode
, type
,
1142 argpos
< n_named_args
);
1144 /* If this is a sibling call and the machine has register windows, the
1145 register window has to be unwinded before calling the routine, so
1146 arguments have to go into the incoming registers. */
1147 if (targetm
.calls
.function_incoming_arg
!= targetm
.calls
.function_arg
)
1148 args
[i
].tail_call_reg
1149 = targetm
.calls
.function_incoming_arg (args_so_far
, mode
, type
,
1150 argpos
< n_named_args
);
1152 args
[i
].tail_call_reg
= args
[i
].reg
;
1156 = targetm
.calls
.arg_partial_bytes (args_so_far
, mode
, type
,
1157 argpos
< n_named_args
);
1159 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (mode
, type
);
1161 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1162 it means that we are to pass this arg in the register(s) designated
1163 by the PARALLEL, but also to pass it in the stack. */
1164 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1165 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1166 args
[i
].pass_on_stack
= 1;
1168 /* If this is an addressable type, we must preallocate the stack
1169 since we must evaluate the object into its final location.
1171 If this is to be passed in both registers and the stack, it is simpler
1173 if (TREE_ADDRESSABLE (type
)
1174 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1175 *must_preallocate
= 1;
1177 /* Compute the stack-size of this argument. */
1178 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1179 || reg_parm_stack_space
> 0
1180 || args
[i
].pass_on_stack
)
1181 locate_and_pad_parm (mode
, type
,
1182 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1187 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
1188 fndecl
, args_size
, &args
[i
].locate
);
1189 #ifdef BLOCK_REG_PADDING
1191 /* The argument is passed entirely in registers. See at which
1192 end it should be padded. */
1193 args
[i
].locate
.where_pad
=
1194 BLOCK_REG_PADDING (mode
, type
,
1195 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
1198 /* Update ARGS_SIZE, the total stack space for args so far. */
1200 args_size
->constant
+= args
[i
].locate
.size
.constant
;
1201 if (args
[i
].locate
.size
.var
)
1202 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
1204 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1205 have been used, etc. */
1207 targetm
.calls
.function_arg_advance (args_so_far
, TYPE_MODE (type
),
1208 type
, argpos
< n_named_args
);
1212 /* Update ARGS_SIZE to contain the total size for the argument block.
1213 Return the original constant component of the argument block's size.
1215 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1216 for arguments passed in registers. */
1219 compute_argument_block_size (int reg_parm_stack_space
,
1220 struct args_size
*args_size
,
1221 tree fndecl ATTRIBUTE_UNUSED
,
1222 tree fntype ATTRIBUTE_UNUSED
,
1223 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
1225 int unadjusted_args_size
= args_size
->constant
;
1227 /* For accumulate outgoing args mode we don't need to align, since the frame
1228 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1229 backends from generating misaligned frame sizes. */
1230 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1231 preferred_stack_boundary
= STACK_BOUNDARY
;
1233 /* Compute the actual size of the argument block required. The variable
1234 and constant sizes must be combined, the size may have to be rounded,
1235 and there may be a minimum required size. */
1239 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1240 args_size
->constant
= 0;
1242 preferred_stack_boundary
/= BITS_PER_UNIT
;
1243 if (preferred_stack_boundary
> 1)
1245 /* We don't handle this case yet. To handle it correctly we have
1246 to add the delta, round and subtract the delta.
1247 Currently no machine description requires this support. */
1248 gcc_assert (!(stack_pointer_delta
& (preferred_stack_boundary
- 1)));
1249 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1252 if (reg_parm_stack_space
> 0)
1255 = size_binop (MAX_EXPR
, args_size
->var
,
1256 ssize_int (reg_parm_stack_space
));
1258 /* The area corresponding to register parameters is not to count in
1259 the size of the block we need. So make the adjustment. */
1260 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
1262 = size_binop (MINUS_EXPR
, args_size
->var
,
1263 ssize_int (reg_parm_stack_space
));
1268 preferred_stack_boundary
/= BITS_PER_UNIT
;
1269 if (preferred_stack_boundary
< 1)
1270 preferred_stack_boundary
= 1;
1271 args_size
->constant
= (((args_size
->constant
1272 + stack_pointer_delta
1273 + preferred_stack_boundary
- 1)
1274 / preferred_stack_boundary
1275 * preferred_stack_boundary
)
1276 - stack_pointer_delta
);
1278 args_size
->constant
= MAX (args_size
->constant
,
1279 reg_parm_stack_space
);
1281 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
1282 args_size
->constant
-= reg_parm_stack_space
;
1284 return unadjusted_args_size
;
1287 /* Precompute parameters as needed for a function call.
1289 FLAGS is mask of ECF_* constants.
1291 NUM_ACTUALS is the number of arguments.
1293 ARGS is an array containing information for each argument; this
1294 routine fills in the INITIAL_VALUE and VALUE fields for each
1295 precomputed argument. */
1298 precompute_arguments (int num_actuals
, struct arg_data
*args
)
1302 /* If this is a libcall, then precompute all arguments so that we do not
1303 get extraneous instructions emitted as part of the libcall sequence. */
1305 /* If we preallocated the stack space, and some arguments must be passed
1306 on the stack, then we must precompute any parameter which contains a
1307 function call which will store arguments on the stack.
1308 Otherwise, evaluating the parameter may clobber previous parameters
1309 which have already been stored into the stack. (we have code to avoid
1310 such case by saving the outgoing stack arguments, but it results in
1312 if (!ACCUMULATE_OUTGOING_ARGS
)
1315 for (i
= 0; i
< num_actuals
; i
++)
1318 enum machine_mode mode
;
1320 if (TREE_CODE (args
[i
].tree_value
) != CALL_EXPR
)
1323 /* If this is an addressable type, we cannot pre-evaluate it. */
1324 type
= TREE_TYPE (args
[i
].tree_value
);
1325 gcc_assert (!TREE_ADDRESSABLE (type
));
1327 args
[i
].initial_value
= args
[i
].value
1328 = expand_normal (args
[i
].tree_value
);
1330 mode
= TYPE_MODE (type
);
1331 if (mode
!= args
[i
].mode
)
1333 int unsignedp
= args
[i
].unsignedp
;
1335 = convert_modes (args
[i
].mode
, mode
,
1336 args
[i
].value
, args
[i
].unsignedp
);
1338 /* CSE will replace this only if it contains args[i].value
1339 pseudo, so convert it down to the declared mode using
1341 if (REG_P (args
[i
].value
)
1342 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
1343 && promote_mode (type
, mode
, &unsignedp
) != args
[i
].mode
)
1345 args
[i
].initial_value
1346 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1347 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1348 SUBREG_PROMOTED_UNSIGNED_SET (args
[i
].initial_value
,
1355 /* Given the current state of MUST_PREALLOCATE and information about
1356 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1357 compute and return the final value for MUST_PREALLOCATE. */
1360 finalize_must_preallocate (int must_preallocate
, int num_actuals
,
1361 struct arg_data
*args
, struct args_size
*args_size
)
1363 /* See if we have or want to preallocate stack space.
1365 If we would have to push a partially-in-regs parm
1366 before other stack parms, preallocate stack space instead.
1368 If the size of some parm is not a multiple of the required stack
1369 alignment, we must preallocate.
1371 If the total size of arguments that would otherwise create a copy in
1372 a temporary (such as a CALL) is more than half the total argument list
1373 size, preallocation is faster.
1375 Another reason to preallocate is if we have a machine (like the m88k)
1376 where stack alignment is required to be maintained between every
1377 pair of insns, not just when the call is made. However, we assume here
1378 that such machines either do not have push insns (and hence preallocation
1379 would occur anyway) or the problem is taken care of with
1382 if (! must_preallocate
)
1384 int partial_seen
= 0;
1385 int copy_to_evaluate_size
= 0;
1388 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1390 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1392 else if (partial_seen
&& args
[i
].reg
== 0)
1393 must_preallocate
= 1;
1395 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1396 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1397 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1398 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1399 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1400 copy_to_evaluate_size
1401 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1404 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1405 && args_size
->constant
> 0)
1406 must_preallocate
= 1;
1408 return must_preallocate
;
1411 /* If we preallocated stack space, compute the address of each argument
1412 and store it into the ARGS array.
1414 We need not ensure it is a valid memory address here; it will be
1415 validized when it is used.
1417 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1420 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
1424 rtx arg_reg
= argblock
;
1425 int i
, arg_offset
= 0;
1427 if (GET_CODE (argblock
) == PLUS
)
1428 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1430 for (i
= 0; i
< num_actuals
; i
++)
1432 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
1433 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
1435 unsigned int align
, boundary
;
1436 unsigned int units_on_stack
= 0;
1437 enum machine_mode partial_mode
= VOIDmode
;
1439 /* Skip this parm if it will not be passed on the stack. */
1440 if (! args
[i
].pass_on_stack
1442 && args
[i
].partial
== 0)
1445 if (CONST_INT_P (offset
))
1446 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1448 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1450 addr
= plus_constant (addr
, arg_offset
);
1452 if (args
[i
].partial
!= 0)
1454 /* Only part of the parameter is being passed on the stack.
1455 Generate a simple memory reference of the correct size. */
1456 units_on_stack
= args
[i
].locate
.size
.constant
;
1457 partial_mode
= mode_for_size (units_on_stack
* BITS_PER_UNIT
,
1459 args
[i
].stack
= gen_rtx_MEM (partial_mode
, addr
);
1460 set_mem_size (args
[i
].stack
, GEN_INT (units_on_stack
));
1464 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1465 set_mem_attributes (args
[i
].stack
,
1466 TREE_TYPE (args
[i
].tree_value
), 1);
1468 align
= BITS_PER_UNIT
;
1469 boundary
= args
[i
].locate
.boundary
;
1470 if (args
[i
].locate
.where_pad
!= downward
)
1472 else if (CONST_INT_P (offset
))
1474 align
= INTVAL (offset
) * BITS_PER_UNIT
| boundary
;
1475 align
= align
& -align
;
1477 set_mem_align (args
[i
].stack
, align
);
1479 if (CONST_INT_P (slot_offset
))
1480 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1482 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1484 addr
= plus_constant (addr
, arg_offset
);
1486 if (args
[i
].partial
!= 0)
1488 /* Only part of the parameter is being passed on the stack.
1489 Generate a simple memory reference of the correct size.
1491 args
[i
].stack_slot
= gen_rtx_MEM (partial_mode
, addr
);
1492 set_mem_size (args
[i
].stack_slot
, GEN_INT (units_on_stack
));
1496 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1497 set_mem_attributes (args
[i
].stack_slot
,
1498 TREE_TYPE (args
[i
].tree_value
), 1);
1500 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
1502 /* Function incoming arguments may overlap with sibling call
1503 outgoing arguments and we cannot allow reordering of reads
1504 from function arguments with stores to outgoing arguments
1505 of sibling calls. */
1506 set_mem_alias_set (args
[i
].stack
, 0);
1507 set_mem_alias_set (args
[i
].stack_slot
, 0);
1512 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1513 in a call instruction.
1515 FNDECL is the tree node for the target function. For an indirect call
1516 FNDECL will be NULL_TREE.
1518 ADDR is the operand 0 of CALL_EXPR for this call. */
1521 rtx_for_function_call (tree fndecl
, tree addr
)
1525 /* Get the function to call, in the form of RTL. */
1528 /* If this is the first use of the function, see if we need to
1529 make an external definition for it. */
1530 if (!TREE_USED (fndecl
) && fndecl
!= current_function_decl
)
1532 assemble_external (fndecl
);
1533 TREE_USED (fndecl
) = 1;
1536 /* Get a SYMBOL_REF rtx for the function address. */
1537 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1540 /* Generate an rtx (probably a pseudo-register) for the address. */
1543 funexp
= expand_normal (addr
);
1544 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1549 /* Return true if and only if SIZE storage units (usually bytes)
1550 starting from address ADDR overlap with already clobbered argument
1551 area. This function is used to determine if we should give up a
1555 mem_overlaps_already_clobbered_arg_p (rtx addr
, unsigned HOST_WIDE_INT size
)
1559 if (addr
== crtl
->args
.internal_arg_pointer
)
1561 else if (GET_CODE (addr
) == PLUS
1562 && XEXP (addr
, 0) == crtl
->args
.internal_arg_pointer
1563 && CONST_INT_P (XEXP (addr
, 1)))
1564 i
= INTVAL (XEXP (addr
, 1));
1565 /* Return true for arg pointer based indexed addressing. */
1566 else if (GET_CODE (addr
) == PLUS
1567 && (XEXP (addr
, 0) == crtl
->args
.internal_arg_pointer
1568 || XEXP (addr
, 1) == crtl
->args
.internal_arg_pointer
))
1573 #ifdef ARGS_GROW_DOWNWARD
1578 unsigned HOST_WIDE_INT k
;
1580 for (k
= 0; k
< size
; k
++)
1581 if (i
+ k
< stored_args_map
->n_bits
1582 && TEST_BIT (stored_args_map
, i
+ k
))
1589 /* Do the register loads required for any wholly-register parms or any
1590 parms which are passed both on the stack and in a register. Their
1591 expressions were already evaluated.
1593 Mark all register-parms as living through the call, putting these USE
1594 insns in the CALL_INSN_FUNCTION_USAGE field.
1596 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1597 checking, setting *SIBCALL_FAILURE if appropriate. */
1600 load_register_parameters (struct arg_data
*args
, int num_actuals
,
1601 rtx
*call_fusage
, int flags
, int is_sibcall
,
1602 int *sibcall_failure
)
1606 for (i
= 0; i
< num_actuals
; i
++)
1608 rtx reg
= ((flags
& ECF_SIBCALL
)
1609 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1612 int partial
= args
[i
].partial
;
1615 rtx before_arg
= get_last_insn ();
1616 /* Set non-negative if we must move a word at a time, even if
1617 just one word (e.g, partial == 4 && mode == DFmode). Set
1618 to -1 if we just use a normal move insn. This value can be
1619 zero if the argument is a zero size structure. */
1621 if (GET_CODE (reg
) == PARALLEL
)
1625 gcc_assert (partial
% UNITS_PER_WORD
== 0);
1626 nregs
= partial
/ UNITS_PER_WORD
;
1628 else if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
)
1630 size
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1631 nregs
= (size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1634 size
= GET_MODE_SIZE (args
[i
].mode
);
1636 /* Handle calls that pass values in multiple non-contiguous
1637 locations. The Irix 6 ABI has examples of this. */
1639 if (GET_CODE (reg
) == PARALLEL
)
1640 emit_group_move (reg
, args
[i
].parallel_value
);
1642 /* If simple case, just do move. If normal partial, store_one_arg
1643 has already loaded the register for us. In all other cases,
1644 load the register(s) from memory. */
1646 else if (nregs
== -1)
1648 emit_move_insn (reg
, args
[i
].value
);
1649 #ifdef BLOCK_REG_PADDING
1650 /* Handle case where we have a value that needs shifting
1651 up to the msb. eg. a QImode value and we're padding
1652 upward on a BYTES_BIG_ENDIAN machine. */
1653 if (size
< UNITS_PER_WORD
1654 && (args
[i
].locate
.where_pad
1655 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
1658 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1660 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1661 report the whole reg as used. Strictly speaking, the
1662 call only uses SIZE bytes at the msb end, but it doesn't
1663 seem worth generating rtl to say that. */
1664 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
1665 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
1666 build_int_cst (NULL_TREE
, shift
),
1669 emit_move_insn (reg
, x
);
1674 /* If we have pre-computed the values to put in the registers in
1675 the case of non-aligned structures, copy them in now. */
1677 else if (args
[i
].n_aligned_regs
!= 0)
1678 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1679 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1680 args
[i
].aligned_regs
[j
]);
1682 else if (partial
== 0 || args
[i
].pass_on_stack
)
1684 rtx mem
= validize_mem (args
[i
].value
);
1686 /* Check for overlap with already clobbered argument area,
1687 providing that this has non-zero size. */
1690 || mem_overlaps_already_clobbered_arg_p
1691 (XEXP (args
[i
].value
, 0), size
)))
1692 *sibcall_failure
= 1;
1694 /* Handle a BLKmode that needs shifting. */
1695 if (nregs
== 1 && size
< UNITS_PER_WORD
1696 #ifdef BLOCK_REG_PADDING
1697 && args
[i
].locate
.where_pad
== downward
1703 rtx tem
= operand_subword_force (mem
, 0, args
[i
].mode
);
1704 rtx ri
= gen_rtx_REG (word_mode
, REGNO (reg
));
1705 rtx x
= gen_reg_rtx (word_mode
);
1706 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1707 enum tree_code dir
= BYTES_BIG_ENDIAN
? RSHIFT_EXPR
1710 emit_move_insn (x
, tem
);
1711 x
= expand_shift (dir
, word_mode
, x
,
1712 build_int_cst (NULL_TREE
, shift
),
1715 emit_move_insn (ri
, x
);
1718 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
1721 /* When a parameter is a block, and perhaps in other cases, it is
1722 possible that it did a load from an argument slot that was
1723 already clobbered. */
1725 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
1726 *sibcall_failure
= 1;
1728 /* Handle calls that pass values in multiple non-contiguous
1729 locations. The Irix 6 ABI has examples of this. */
1730 if (GET_CODE (reg
) == PARALLEL
)
1731 use_group_regs (call_fusage
, reg
);
1732 else if (nregs
== -1)
1733 use_reg (call_fusage
, reg
);
1735 use_regs (call_fusage
, REGNO (reg
), nregs
);
1740 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1741 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1742 bytes, then we would need to push some additional bytes to pad the
1743 arguments. So, we compute an adjust to the stack pointer for an
1744 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1745 bytes. Then, when the arguments are pushed the stack will be perfectly
1746 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1747 be popped after the call. Returns the adjustment. */
1750 combine_pending_stack_adjustment_and_call (int unadjusted_args_size
,
1751 struct args_size
*args_size
,
1752 unsigned int preferred_unit_stack_boundary
)
1754 /* The number of bytes to pop so that the stack will be
1755 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1756 HOST_WIDE_INT adjustment
;
1757 /* The alignment of the stack after the arguments are pushed, if we
1758 just pushed the arguments without adjust the stack here. */
1759 unsigned HOST_WIDE_INT unadjusted_alignment
;
1761 unadjusted_alignment
1762 = ((stack_pointer_delta
+ unadjusted_args_size
)
1763 % preferred_unit_stack_boundary
);
1765 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1766 as possible -- leaving just enough left to cancel out the
1767 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1768 PENDING_STACK_ADJUST is non-negative, and congruent to
1769 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1771 /* Begin by trying to pop all the bytes. */
1772 unadjusted_alignment
1773 = (unadjusted_alignment
1774 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1775 adjustment
= pending_stack_adjust
;
1776 /* Push enough additional bytes that the stack will be aligned
1777 after the arguments are pushed. */
1778 if (preferred_unit_stack_boundary
> 1)
1780 if (unadjusted_alignment
> 0)
1781 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1783 adjustment
+= unadjusted_alignment
;
1786 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1787 bytes after the call. The right number is the entire
1788 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1789 by the arguments in the first place. */
1791 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1796 /* Scan X expression if it does not dereference any argument slots
1797 we already clobbered by tail call arguments (as noted in stored_args_map
1799 Return nonzero if X expression dereferences such argument slots,
1803 check_sibcall_argument_overlap_1 (rtx x
)
1812 code
= GET_CODE (x
);
1815 return mem_overlaps_already_clobbered_arg_p (XEXP (x
, 0),
1816 GET_MODE_SIZE (GET_MODE (x
)));
1818 /* Scan all subexpressions. */
1819 fmt
= GET_RTX_FORMAT (code
);
1820 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
1824 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
1827 else if (*fmt
== 'E')
1829 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
1830 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
1837 /* Scan sequence after INSN if it does not dereference any argument slots
1838 we already clobbered by tail call arguments (as noted in stored_args_map
1839 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1840 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1841 should be 0). Return nonzero if sequence after INSN dereferences such argument
1842 slots, zero otherwise. */
1845 check_sibcall_argument_overlap (rtx insn
, struct arg_data
*arg
, int mark_stored_args_map
)
1849 if (insn
== NULL_RTX
)
1850 insn
= get_insns ();
1852 insn
= NEXT_INSN (insn
);
1854 for (; insn
; insn
= NEXT_INSN (insn
))
1856 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
1859 if (mark_stored_args_map
)
1861 #ifdef ARGS_GROW_DOWNWARD
1862 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
1864 low
= arg
->locate
.slot_offset
.constant
;
1867 for (high
= low
+ arg
->locate
.size
.constant
; low
< high
; low
++)
1868 SET_BIT (stored_args_map
, low
);
1870 return insn
!= NULL_RTX
;
1873 /* Given that a function returns a value of mode MODE at the most
1874 significant end of hard register VALUE, shift VALUE left or right
1875 as specified by LEFT_P. Return true if some action was needed. */
1878 shift_return_value (enum machine_mode mode
, bool left_p
, rtx value
)
1880 HOST_WIDE_INT shift
;
1882 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
1883 shift
= GET_MODE_BITSIZE (GET_MODE (value
)) - GET_MODE_BITSIZE (mode
);
1887 /* Use ashr rather than lshr for right shifts. This is for the benefit
1888 of the MIPS port, which requires SImode values to be sign-extended
1889 when stored in 64-bit registers. */
1890 if (!force_expand_binop (GET_MODE (value
), left_p
? ashl_optab
: ashr_optab
,
1891 value
, GEN_INT (shift
), value
, 1, OPTAB_WIDEN
))
1896 /* If X is a likely-spilled register value, copy it to a pseudo
1897 register and return that register. Return X otherwise. */
1900 avoid_likely_spilled_reg (rtx x
)
1905 && HARD_REGISTER_P (x
)
1906 && targetm
.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x
))))
1908 /* Make sure that we generate a REG rather than a CONCAT.
1909 Moves into CONCATs can need nontrivial instructions,
1910 and the whole point of this function is to avoid
1911 using the hard register directly in such a situation. */
1912 generating_concat_p
= 0;
1913 new_rtx
= gen_reg_rtx (GET_MODE (x
));
1914 generating_concat_p
= 1;
1915 emit_move_insn (new_rtx
, x
);
1921 /* Generate all the code for a CALL_EXPR exp
1922 and return an rtx for its value.
1923 Store the value in TARGET (specified as an rtx) if convenient.
1924 If the value is stored in TARGET then TARGET is returned.
1925 If IGNORE is nonzero, then we ignore the value of the function call. */
1928 expand_call (tree exp
, rtx target
, int ignore
)
1930 /* Nonzero if we are currently expanding a call. */
1931 static int currently_expanding_call
= 0;
1933 /* RTX for the function to be called. */
1935 /* Sequence of insns to perform a normal "call". */
1936 rtx normal_call_insns
= NULL_RTX
;
1937 /* Sequence of insns to perform a tail "call". */
1938 rtx tail_call_insns
= NULL_RTX
;
1939 /* Data type of the function. */
1941 tree type_arg_types
;
1943 /* Declaration of the function being called,
1944 or 0 if the function is computed (not known by name). */
1946 /* The type of the function being called. */
1948 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
1951 /* Register in which non-BLKmode value will be returned,
1952 or 0 if no value or if value is BLKmode. */
1954 /* Address where we should return a BLKmode value;
1955 0 if value not BLKmode. */
1956 rtx structure_value_addr
= 0;
1957 /* Nonzero if that address is being passed by treating it as
1958 an extra, implicit first parameter. Otherwise,
1959 it is passed by being copied directly into struct_value_rtx. */
1960 int structure_value_addr_parm
= 0;
1961 /* Holds the value of implicit argument for the struct value. */
1962 tree structure_value_addr_value
= NULL_TREE
;
1963 /* Size of aggregate value wanted, or zero if none wanted
1964 or if we are using the non-reentrant PCC calling convention
1965 or expecting the value in registers. */
1966 HOST_WIDE_INT struct_value_size
= 0;
1967 /* Nonzero if called function returns an aggregate in memory PCC style,
1968 by returning the address of where to find it. */
1969 int pcc_struct_value
= 0;
1970 rtx struct_value
= 0;
1972 /* Number of actual parameters in this call, including struct value addr. */
1974 /* Number of named args. Args after this are anonymous ones
1975 and they must all go on the stack. */
1977 /* Number of complex actual arguments that need to be split. */
1978 int num_complex_actuals
= 0;
1980 /* Vector of information about each argument.
1981 Arguments are numbered in the order they will be pushed,
1982 not the order they are written. */
1983 struct arg_data
*args
;
1985 /* Total size in bytes of all the stack-parms scanned so far. */
1986 struct args_size args_size
;
1987 struct args_size adjusted_args_size
;
1988 /* Size of arguments before any adjustments (such as rounding). */
1989 int unadjusted_args_size
;
1990 /* Data on reg parms scanned so far. */
1991 CUMULATIVE_ARGS args_so_far
;
1992 /* Nonzero if a reg parm has been scanned. */
1994 /* Nonzero if this is an indirect function call. */
1996 /* Nonzero if we must avoid push-insns in the args for this call.
1997 If stack space is allocated for register parameters, but not by the
1998 caller, then it is preallocated in the fixed part of the stack frame.
1999 So the entire argument block must then be preallocated (i.e., we
2000 ignore PUSH_ROUNDING in that case). */
2002 int must_preallocate
= !PUSH_ARGS
;
2004 /* Size of the stack reserved for parameter registers. */
2005 int reg_parm_stack_space
= 0;
2007 /* Address of space preallocated for stack parms
2008 (on machines that lack push insns), or 0 if space not preallocated. */
2011 /* Mask of ECF_ flags. */
2013 #ifdef REG_PARM_STACK_SPACE
2014 /* Define the boundary of the register parm stack space that needs to be
2016 int low_to_save
, high_to_save
;
2017 rtx save_area
= 0; /* Place that it is saved */
2020 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
2021 char *initial_stack_usage_map
= stack_usage_map
;
2022 char *stack_usage_map_buf
= NULL
;
2024 int old_stack_allocated
;
2026 /* State variables to track stack modifications. */
2027 rtx old_stack_level
= 0;
2028 int old_stack_arg_under_construction
= 0;
2029 int old_pending_adj
= 0;
2030 int old_inhibit_defer_pop
= inhibit_defer_pop
;
2032 /* Some stack pointer alterations we make are performed via
2033 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2034 which we then also need to save/restore along the way. */
2035 int old_stack_pointer_delta
= 0;
2038 tree addr
= CALL_EXPR_FN (exp
);
2040 /* The alignment of the stack, in bits. */
2041 unsigned HOST_WIDE_INT preferred_stack_boundary
;
2042 /* The alignment of the stack, in bytes. */
2043 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
2044 /* The static chain value to use for this call. */
2045 rtx static_chain_value
;
2046 /* See if this is "nothrow" function call. */
2047 if (TREE_NOTHROW (exp
))
2048 flags
|= ECF_NOTHROW
;
2050 /* See if we can find a DECL-node for the actual function, and get the
2051 function attributes (flags) from the function decl or type node. */
2052 fndecl
= get_callee_fndecl (exp
);
2055 fntype
= TREE_TYPE (fndecl
);
2056 flags
|= flags_from_decl_or_type (fndecl
);
2060 fntype
= TREE_TYPE (TREE_TYPE (addr
));
2061 flags
|= flags_from_decl_or_type (fntype
);
2063 rettype
= TREE_TYPE (exp
);
2065 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
2067 /* Warn if this value is an aggregate type,
2068 regardless of which calling convention we are using for it. */
2069 if (AGGREGATE_TYPE_P (rettype
))
2070 warning (OPT_Waggregate_return
, "function call has aggregate value");
2072 /* If the result of a non looping pure or const function call is
2073 ignored (or void), and none of its arguments are volatile, we can
2074 avoid expanding the call and just evaluate the arguments for
2076 if ((flags
& (ECF_CONST
| ECF_PURE
))
2077 && (!(flags
& ECF_LOOPING_CONST_OR_PURE
))
2078 && (ignore
|| target
== const0_rtx
2079 || TYPE_MODE (rettype
) == VOIDmode
))
2081 bool volatilep
= false;
2083 call_expr_arg_iterator iter
;
2085 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2086 if (TREE_THIS_VOLATILE (arg
))
2094 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2095 expand_expr (arg
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
2100 #ifdef REG_PARM_STACK_SPACE
2101 reg_parm_stack_space
= REG_PARM_STACK_SPACE (!fndecl
? fntype
: fndecl
);
2104 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
2105 && reg_parm_stack_space
> 0 && PUSH_ARGS
)
2106 must_preallocate
= 1;
2108 /* Set up a place to return a structure. */
2110 /* Cater to broken compilers. */
2111 if (aggregate_value_p (exp
, fntype
))
2113 /* This call returns a big structure. */
2114 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
2116 #ifdef PCC_STATIC_STRUCT_RETURN
2118 pcc_struct_value
= 1;
2120 #else /* not PCC_STATIC_STRUCT_RETURN */
2122 struct_value_size
= int_size_in_bytes (rettype
);
2124 if (target
&& MEM_P (target
) && CALL_EXPR_RETURN_SLOT_OPT (exp
))
2125 structure_value_addr
= XEXP (target
, 0);
2128 /* For variable-sized objects, we must be called with a target
2129 specified. If we were to allocate space on the stack here,
2130 we would have no way of knowing when to free it. */
2131 rtx d
= assign_temp (rettype
, 0, 1, 1);
2133 mark_temp_addr_taken (d
);
2134 structure_value_addr
= XEXP (d
, 0);
2138 #endif /* not PCC_STATIC_STRUCT_RETURN */
2141 /* Figure out the amount to which the stack should be aligned. */
2142 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2145 struct cgraph_rtl_info
*i
= cgraph_rtl_info (fndecl
);
2146 /* Without automatic stack alignment, we can't increase preferred
2147 stack boundary. With automatic stack alignment, it is
2148 unnecessary since unless we can guarantee that all callers will
2149 align the outgoing stack properly, callee has to align its
2152 && i
->preferred_incoming_stack_boundary
2153 && i
->preferred_incoming_stack_boundary
< preferred_stack_boundary
)
2154 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
2157 /* Operand 0 is a pointer-to-function; get the type of the function. */
2158 funtype
= TREE_TYPE (addr
);
2159 gcc_assert (POINTER_TYPE_P (funtype
));
2160 funtype
= TREE_TYPE (funtype
);
2162 /* Count whether there are actual complex arguments that need to be split
2163 into their real and imaginary parts. Munge the type_arg_types
2164 appropriately here as well. */
2165 if (targetm
.calls
.split_complex_arg
)
2167 call_expr_arg_iterator iter
;
2169 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2171 tree type
= TREE_TYPE (arg
);
2172 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
2173 && targetm
.calls
.split_complex_arg (type
))
2174 num_complex_actuals
++;
2176 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
2179 type_arg_types
= TYPE_ARG_TYPES (funtype
);
2181 if (flags
& ECF_MAY_BE_ALLOCA
)
2182 cfun
->calls_alloca
= 1;
2184 /* If struct_value_rtx is 0, it means pass the address
2185 as if it were an extra parameter. Put the argument expression
2186 in structure_value_addr_value. */
2187 if (structure_value_addr
&& struct_value
== 0)
2189 /* If structure_value_addr is a REG other than
2190 virtual_outgoing_args_rtx, we can use always use it. If it
2191 is not a REG, we must always copy it into a register.
2192 If it is virtual_outgoing_args_rtx, we must copy it to another
2193 register in some cases. */
2194 rtx temp
= (!REG_P (structure_value_addr
)
2195 || (ACCUMULATE_OUTGOING_ARGS
2196 && stack_arg_under_construction
2197 && structure_value_addr
== virtual_outgoing_args_rtx
)
2198 ? copy_addr_to_reg (convert_memory_address
2199 (Pmode
, structure_value_addr
))
2200 : structure_value_addr
);
2202 structure_value_addr_value
=
2203 make_tree (build_pointer_type (TREE_TYPE (funtype
)), temp
);
2204 structure_value_addr_parm
= 1;
2207 /* Count the arguments and set NUM_ACTUALS. */
2209 call_expr_nargs (exp
) + num_complex_actuals
+ structure_value_addr_parm
;
2211 /* Compute number of named args.
2212 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2214 if (type_arg_types
!= 0)
2216 = (list_length (type_arg_types
)
2217 /* Count the struct value address, if it is passed as a parm. */
2218 + structure_value_addr_parm
);
2220 /* If we know nothing, treat all args as named. */
2221 n_named_args
= num_actuals
;
2223 /* Start updating where the next arg would go.
2225 On some machines (such as the PA) indirect calls have a different
2226 calling convention than normal calls. The fourth argument in
2227 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2229 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
2231 /* Now possibly adjust the number of named args.
2232 Normally, don't include the last named arg if anonymous args follow.
2233 We do include the last named arg if
2234 targetm.calls.strict_argument_naming() returns nonzero.
2235 (If no anonymous args follow, the result of list_length is actually
2236 one too large. This is harmless.)
2238 If targetm.calls.pretend_outgoing_varargs_named() returns
2239 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2240 this machine will be able to place unnamed args that were passed
2241 in registers into the stack. So treat all args as named. This
2242 allows the insns emitting for a specific argument list to be
2243 independent of the function declaration.
2245 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2246 we do not have any reliable way to pass unnamed args in
2247 registers, so we must force them into memory. */
2249 if (type_arg_types
!= 0
2250 && targetm
.calls
.strict_argument_naming (&args_so_far
))
2252 else if (type_arg_types
!= 0
2253 && ! targetm
.calls
.pretend_outgoing_varargs_named (&args_so_far
))
2254 /* Don't include the last named arg. */
2257 /* Treat all args as named. */
2258 n_named_args
= num_actuals
;
2260 /* Make a vector to hold all the information about each arg. */
2261 args
= XALLOCAVEC (struct arg_data
, num_actuals
);
2262 memset (args
, 0, num_actuals
* sizeof (struct arg_data
));
2264 /* Build up entries in the ARGS array, compute the size of the
2265 arguments into ARGS_SIZE, etc. */
2266 initialize_argument_information (num_actuals
, args
, &args_size
,
2268 structure_value_addr_value
, fndecl
, fntype
,
2269 &args_so_far
, reg_parm_stack_space
,
2270 &old_stack_level
, &old_pending_adj
,
2271 &must_preallocate
, &flags
,
2272 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
2275 must_preallocate
= 1;
2277 /* Now make final decision about preallocating stack space. */
2278 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2282 /* If the structure value address will reference the stack pointer, we
2283 must stabilize it. We don't need to do this if we know that we are
2284 not going to adjust the stack pointer in processing this call. */
2286 if (structure_value_addr
2287 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2288 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2289 structure_value_addr
))
2291 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2292 structure_value_addr
= copy_to_reg (structure_value_addr
);
2294 /* Tail calls can make things harder to debug, and we've traditionally
2295 pushed these optimizations into -O2. Don't try if we're already
2296 expanding a call, as that means we're an argument. Don't try if
2297 there's cleanups, as we know there's code to follow the call. */
2299 if (currently_expanding_call
++ != 0
2300 || !flag_optimize_sibling_calls
2302 || dbg_cnt (tail_call
) == false)
2305 /* Rest of purposes for tail call optimizations to fail. */
2307 #ifdef HAVE_sibcall_epilogue
2308 !HAVE_sibcall_epilogue
2313 /* Doing sibling call optimization needs some work, since
2314 structure_value_addr can be allocated on the stack.
2315 It does not seem worth the effort since few optimizable
2316 sibling calls will return a structure. */
2317 || structure_value_addr
!= NULL_RTX
2318 #ifdef REG_PARM_STACK_SPACE
2319 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2320 || (OUTGOING_REG_PARM_STACK_SPACE (funtype
)
2321 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl
)))
2322 || (reg_parm_stack_space
!= REG_PARM_STACK_SPACE (fndecl
))
2324 /* Check whether the target is able to optimize the call
2326 || !targetm
.function_ok_for_sibcall (fndecl
, exp
)
2327 /* Functions that do not return exactly once may not be sibcall
2329 || (flags
& (ECF_RETURNS_TWICE
| ECF_NORETURN
))
2330 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
)))
2331 /* If the called function is nested in the current one, it might access
2332 some of the caller's arguments, but could clobber them beforehand if
2333 the argument areas are shared. */
2334 || (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
2335 /* If this function requires more stack slots than the current
2336 function, we cannot change it into a sibling call.
2337 crtl->args.pretend_args_size is not part of the
2338 stack allocated by our caller. */
2339 || args_size
.constant
> (crtl
->args
.size
2340 - crtl
->args
.pretend_args_size
)
2341 /* If the callee pops its own arguments, then it must pop exactly
2342 the same number of arguments as the current function. */
2343 || (targetm
.calls
.return_pops_args (fndecl
, funtype
, args_size
.constant
)
2344 != targetm
.calls
.return_pops_args (current_function_decl
,
2345 TREE_TYPE (current_function_decl
),
2347 || !lang_hooks
.decls
.ok_for_sibcall (fndecl
))
2350 /* Check if caller and callee disagree in promotion of function
2354 enum machine_mode caller_mode
, caller_promoted_mode
;
2355 enum machine_mode callee_mode
, callee_promoted_mode
;
2356 int caller_unsignedp
, callee_unsignedp
;
2357 tree caller_res
= DECL_RESULT (current_function_decl
);
2359 caller_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (caller_res
));
2360 caller_mode
= DECL_MODE (caller_res
);
2361 callee_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (funtype
));
2362 callee_mode
= TYPE_MODE (TREE_TYPE (funtype
));
2363 caller_promoted_mode
2364 = promote_function_mode (TREE_TYPE (caller_res
), caller_mode
,
2366 TREE_TYPE (current_function_decl
), 1);
2367 callee_promoted_mode
2368 = promote_function_mode (TREE_TYPE (funtype
), callee_mode
,
2371 if (caller_mode
!= VOIDmode
2372 && (caller_promoted_mode
!= callee_promoted_mode
2373 || ((caller_mode
!= caller_promoted_mode
2374 || callee_mode
!= callee_promoted_mode
)
2375 && (caller_unsignedp
!= callee_unsignedp
2376 || GET_MODE_BITSIZE (caller_mode
)
2377 < GET_MODE_BITSIZE (callee_mode
)))))
2381 /* Ensure current function's preferred stack boundary is at least
2382 what we need. Stack alignment may also increase preferred stack
2384 if (crtl
->preferred_stack_boundary
< preferred_stack_boundary
)
2385 crtl
->preferred_stack_boundary
= preferred_stack_boundary
;
2387 preferred_stack_boundary
= crtl
->preferred_stack_boundary
;
2389 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2391 /* We want to make two insn chains; one for a sibling call, the other
2392 for a normal call. We will select one of the two chains after
2393 initial RTL generation is complete. */
2394 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
2396 int sibcall_failure
= 0;
2397 /* We want to emit any pending stack adjustments before the tail
2398 recursion "call". That way we know any adjustment after the tail
2399 recursion call can be ignored if we indeed use the tail
2401 int save_pending_stack_adjust
= 0;
2402 int save_stack_pointer_delta
= 0;
2404 rtx before_call
, next_arg_reg
, after_args
;
2408 /* State variables we need to save and restore between
2410 save_pending_stack_adjust
= pending_stack_adjust
;
2411 save_stack_pointer_delta
= stack_pointer_delta
;
2414 flags
&= ~ECF_SIBCALL
;
2416 flags
|= ECF_SIBCALL
;
2418 /* Other state variables that we must reinitialize each time
2419 through the loop (that are not initialized by the loop itself). */
2423 /* Start a new sequence for the normal call case.
2425 From this point on, if the sibling call fails, we want to set
2426 sibcall_failure instead of continuing the loop. */
2429 /* Don't let pending stack adjusts add up to too much.
2430 Also, do all pending adjustments now if there is any chance
2431 this might be a call to alloca or if we are expanding a sibling
2433 Also do the adjustments before a throwing call, otherwise
2434 exception handling can fail; PR 19225. */
2435 if (pending_stack_adjust
>= 32
2436 || (pending_stack_adjust
> 0
2437 && (flags
& ECF_MAY_BE_ALLOCA
))
2438 || (pending_stack_adjust
> 0
2439 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
2441 do_pending_stack_adjust ();
2443 /* Precompute any arguments as needed. */
2445 precompute_arguments (num_actuals
, args
);
2447 /* Now we are about to start emitting insns that can be deleted
2448 if a libcall is deleted. */
2449 if (pass
&& (flags
& ECF_MALLOC
))
2452 if (pass
== 0 && crtl
->stack_protect_guard
)
2453 stack_protect_epilogue ();
2455 adjusted_args_size
= args_size
;
2456 /* Compute the actual size of the argument block required. The variable
2457 and constant sizes must be combined, the size may have to be rounded,
2458 and there may be a minimum required size. When generating a sibcall
2459 pattern, do not round up, since we'll be re-using whatever space our
2461 unadjusted_args_size
2462 = compute_argument_block_size (reg_parm_stack_space
,
2463 &adjusted_args_size
,
2466 : preferred_stack_boundary
));
2468 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2470 /* The argument block when performing a sibling call is the
2471 incoming argument block. */
2474 argblock
= crtl
->args
.internal_arg_pointer
;
2476 #ifdef STACK_GROWS_DOWNWARD
2477 = plus_constant (argblock
, crtl
->args
.pretend_args_size
);
2479 = plus_constant (argblock
, -crtl
->args
.pretend_args_size
);
2481 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2482 sbitmap_zero (stored_args_map
);
2485 /* If we have no actual push instructions, or shouldn't use them,
2486 make space for all args right now. */
2487 else if (adjusted_args_size
.var
!= 0)
2489 if (old_stack_level
== 0)
2491 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
2492 old_stack_pointer_delta
= stack_pointer_delta
;
2493 old_pending_adj
= pending_stack_adjust
;
2494 pending_stack_adjust
= 0;
2495 /* stack_arg_under_construction says whether a stack arg is
2496 being constructed at the old stack level. Pushing the stack
2497 gets a clean outgoing argument block. */
2498 old_stack_arg_under_construction
= stack_arg_under_construction
;
2499 stack_arg_under_construction
= 0;
2501 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2502 if (flag_stack_usage
)
2503 current_function_has_unbounded_dynamic_stack_size
= 1;
2507 /* Note that we must go through the motions of allocating an argument
2508 block even if the size is zero because we may be storing args
2509 in the area reserved for register arguments, which may be part of
2512 int needed
= adjusted_args_size
.constant
;
2514 /* Store the maximum argument space used. It will be pushed by
2515 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2518 if (needed
> crtl
->outgoing_args_size
)
2519 crtl
->outgoing_args_size
= needed
;
2521 if (must_preallocate
)
2523 if (ACCUMULATE_OUTGOING_ARGS
)
2525 /* Since the stack pointer will never be pushed, it is
2526 possible for the evaluation of a parm to clobber
2527 something we have already written to the stack.
2528 Since most function calls on RISC machines do not use
2529 the stack, this is uncommon, but must work correctly.
2531 Therefore, we save any area of the stack that was already
2532 written and that we are using. Here we set up to do this
2533 by making a new stack usage map from the old one. The
2534 actual save will be done by store_one_arg.
2536 Another approach might be to try to reorder the argument
2537 evaluations to avoid this conflicting stack usage. */
2539 /* Since we will be writing into the entire argument area,
2540 the map must be allocated for its entire size, not just
2541 the part that is the responsibility of the caller. */
2542 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2543 needed
+= reg_parm_stack_space
;
2545 #ifdef ARGS_GROW_DOWNWARD
2546 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2549 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2552 if (stack_usage_map_buf
)
2553 free (stack_usage_map_buf
);
2554 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
2555 stack_usage_map
= stack_usage_map_buf
;
2557 if (initial_highest_arg_in_use
)
2558 memcpy (stack_usage_map
, initial_stack_usage_map
,
2559 initial_highest_arg_in_use
);
2561 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2562 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2563 (highest_outgoing_arg_in_use
2564 - initial_highest_arg_in_use
));
2567 /* The address of the outgoing argument list must not be
2568 copied to a register here, because argblock would be left
2569 pointing to the wrong place after the call to
2570 allocate_dynamic_stack_space below. */
2572 argblock
= virtual_outgoing_args_rtx
;
2576 if (inhibit_defer_pop
== 0)
2578 /* Try to reuse some or all of the pending_stack_adjust
2579 to get this space. */
2581 = (combine_pending_stack_adjustment_and_call
2582 (unadjusted_args_size
,
2583 &adjusted_args_size
,
2584 preferred_unit_stack_boundary
));
2586 /* combine_pending_stack_adjustment_and_call computes
2587 an adjustment before the arguments are allocated.
2588 Account for them and see whether or not the stack
2589 needs to go up or down. */
2590 needed
= unadjusted_args_size
- needed
;
2594 /* We're releasing stack space. */
2595 /* ??? We can avoid any adjustment at all if we're
2596 already aligned. FIXME. */
2597 pending_stack_adjust
= -needed
;
2598 do_pending_stack_adjust ();
2602 /* We need to allocate space. We'll do that in
2603 push_block below. */
2604 pending_stack_adjust
= 0;
2607 /* Special case this because overhead of `push_block' in
2608 this case is non-trivial. */
2610 argblock
= virtual_outgoing_args_rtx
;
2613 argblock
= push_block (GEN_INT (needed
), 0, 0);
2614 #ifdef ARGS_GROW_DOWNWARD
2615 argblock
= plus_constant (argblock
, needed
);
2619 /* We only really need to call `copy_to_reg' in the case
2620 where push insns are going to be used to pass ARGBLOCK
2621 to a function call in ARGS. In that case, the stack
2622 pointer changes value from the allocation point to the
2623 call point, and hence the value of
2624 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2625 as well always do it. */
2626 argblock
= copy_to_reg (argblock
);
2631 if (ACCUMULATE_OUTGOING_ARGS
)
2633 /* The save/restore code in store_one_arg handles all
2634 cases except one: a constructor call (including a C
2635 function returning a BLKmode struct) to initialize
2637 if (stack_arg_under_construction
)
2640 = GEN_INT (adjusted_args_size
.constant
2641 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
2642 : TREE_TYPE (fndecl
))) ? 0
2643 : reg_parm_stack_space
));
2644 if (old_stack_level
== 0)
2646 emit_stack_save (SAVE_BLOCK
, &old_stack_level
,
2648 old_stack_pointer_delta
= stack_pointer_delta
;
2649 old_pending_adj
= pending_stack_adjust
;
2650 pending_stack_adjust
= 0;
2651 /* stack_arg_under_construction says whether a stack
2652 arg is being constructed at the old stack level.
2653 Pushing the stack gets a clean outgoing argument
2655 old_stack_arg_under_construction
2656 = stack_arg_under_construction
;
2657 stack_arg_under_construction
= 0;
2658 /* Make a new map for the new argument list. */
2659 if (stack_usage_map_buf
)
2660 free (stack_usage_map_buf
);
2661 stack_usage_map_buf
= XCNEWVEC (char, highest_outgoing_arg_in_use
);
2662 stack_usage_map
= stack_usage_map_buf
;
2663 highest_outgoing_arg_in_use
= 0;
2665 /* We can pass TRUE as the 4th argument because we just
2666 saved the stack pointer and will restore it right after
2668 allocate_dynamic_stack_space (push_size
, 0,
2669 BIGGEST_ALIGNMENT
, true);
2672 /* If argument evaluation might modify the stack pointer,
2673 copy the address of the argument list to a register. */
2674 for (i
= 0; i
< num_actuals
; i
++)
2675 if (args
[i
].pass_on_stack
)
2677 argblock
= copy_addr_to_reg (argblock
);
2682 compute_argument_addresses (args
, argblock
, num_actuals
);
2684 /* If we push args individually in reverse order, perform stack alignment
2685 before the first push (the last arg). */
2686 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2687 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2689 /* When the stack adjustment is pending, we get better code
2690 by combining the adjustments. */
2691 if (pending_stack_adjust
2692 && ! inhibit_defer_pop
)
2694 pending_stack_adjust
2695 = (combine_pending_stack_adjustment_and_call
2696 (unadjusted_args_size
,
2697 &adjusted_args_size
,
2698 preferred_unit_stack_boundary
));
2699 do_pending_stack_adjust ();
2701 else if (argblock
== 0)
2702 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2703 - unadjusted_args_size
));
2705 /* Now that the stack is properly aligned, pops can't safely
2706 be deferred during the evaluation of the arguments. */
2709 /* Record the maximum pushed stack space size. We need to delay
2710 doing it this far to take into account the optimization done
2711 by combine_pending_stack_adjustment_and_call. */
2712 if (flag_stack_usage
2713 && !ACCUMULATE_OUTGOING_ARGS
2715 && adjusted_args_size
.var
== 0)
2717 int pushed
= adjusted_args_size
.constant
+ pending_stack_adjust
;
2718 if (pushed
> current_function_pushed_stack_size
)
2719 current_function_pushed_stack_size
= pushed
;
2722 funexp
= rtx_for_function_call (fndecl
, addr
);
2724 /* Figure out the register where the value, if any, will come back. */
2726 if (TYPE_MODE (rettype
) != VOIDmode
2727 && ! structure_value_addr
)
2729 if (pcc_struct_value
)
2730 valreg
= hard_function_value (build_pointer_type (rettype
),
2731 fndecl
, NULL
, (pass
== 0));
2733 valreg
= hard_function_value (rettype
, fndecl
, fntype
,
2736 /* If VALREG is a PARALLEL whose first member has a zero
2737 offset, use that. This is for targets such as m68k that
2738 return the same value in multiple places. */
2739 if (GET_CODE (valreg
) == PARALLEL
)
2741 rtx elem
= XVECEXP (valreg
, 0, 0);
2742 rtx where
= XEXP (elem
, 0);
2743 rtx offset
= XEXP (elem
, 1);
2744 if (offset
== const0_rtx
2745 && GET_MODE (where
) == GET_MODE (valreg
))
2750 /* Precompute all register parameters. It isn't safe to compute anything
2751 once we have started filling any specific hard regs. */
2752 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2754 if (CALL_EXPR_STATIC_CHAIN (exp
))
2755 static_chain_value
= expand_normal (CALL_EXPR_STATIC_CHAIN (exp
));
2757 static_chain_value
= 0;
2759 #ifdef REG_PARM_STACK_SPACE
2760 /* Save the fixed argument area if it's part of the caller's frame and
2761 is clobbered by argument setup for this call. */
2762 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2763 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2764 &low_to_save
, &high_to_save
);
2767 /* Now store (and compute if necessary) all non-register parms.
2768 These come before register parms, since they can require block-moves,
2769 which could clobber the registers used for register parms.
2770 Parms which have partial registers are not stored here,
2771 but we do preallocate space here if they want that. */
2773 for (i
= 0; i
< num_actuals
; i
++)
2775 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2777 rtx before_arg
= get_last_insn ();
2779 if (store_one_arg (&args
[i
], argblock
, flags
,
2780 adjusted_args_size
.var
!= 0,
2781 reg_parm_stack_space
)
2783 && check_sibcall_argument_overlap (before_arg
,
2785 sibcall_failure
= 1;
2788 if (((flags
& ECF_CONST
)
2789 || ((flags
& ECF_PURE
) && ACCUMULATE_OUTGOING_ARGS
))
2791 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
2792 gen_rtx_USE (VOIDmode
,
2797 /* If we have a parm that is passed in registers but not in memory
2798 and whose alignment does not permit a direct copy into registers,
2799 make a group of pseudos that correspond to each register that we
2801 if (STRICT_ALIGNMENT
)
2802 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2804 /* Now store any partially-in-registers parm.
2805 This is the last place a block-move can happen. */
2807 for (i
= 0; i
< num_actuals
; i
++)
2808 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2810 rtx before_arg
= get_last_insn ();
2812 if (store_one_arg (&args
[i
], argblock
, flags
,
2813 adjusted_args_size
.var
!= 0,
2814 reg_parm_stack_space
)
2816 && check_sibcall_argument_overlap (before_arg
,
2818 sibcall_failure
= 1;
2821 /* If we pushed args in forward order, perform stack alignment
2822 after pushing the last arg. */
2823 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
2824 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2825 - unadjusted_args_size
));
2827 /* If register arguments require space on the stack and stack space
2828 was not preallocated, allocate stack space here for arguments
2829 passed in registers. */
2830 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
2831 && !ACCUMULATE_OUTGOING_ARGS
2832 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
2833 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
2835 /* Pass the function the address in which to return a
2837 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
2839 structure_value_addr
2840 = convert_memory_address (Pmode
, structure_value_addr
);
2841 emit_move_insn (struct_value
,
2843 force_operand (structure_value_addr
,
2846 if (REG_P (struct_value
))
2847 use_reg (&call_fusage
, struct_value
);
2850 after_args
= get_last_insn ();
2851 funexp
= prepare_call_address (fndecl
, funexp
, static_chain_value
,
2852 &call_fusage
, reg_parm_seen
, pass
== 0);
2854 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
2855 pass
== 0, &sibcall_failure
);
2857 /* Save a pointer to the last insn before the call, so that we can
2858 later safely search backwards to find the CALL_INSN. */
2859 before_call
= get_last_insn ();
2861 /* Set up next argument register. For sibling calls on machines
2862 with register windows this should be the incoming register. */
2864 next_arg_reg
= targetm
.calls
.function_incoming_arg (&args_so_far
,
2869 next_arg_reg
= targetm
.calls
.function_arg (&args_so_far
,
2870 VOIDmode
, void_type_node
,
2873 /* All arguments and registers used for the call must be set up by
2876 /* Stack must be properly aligned now. */
2878 || !(stack_pointer_delta
% preferred_unit_stack_boundary
));
2880 /* Generate the actual call instruction. */
2881 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
2882 adjusted_args_size
.constant
, struct_value_size
,
2883 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
2884 flags
, & args_so_far
);
2886 /* If the call setup or the call itself overlaps with anything
2887 of the argument setup we probably clobbered our call address.
2888 In that case we can't do sibcalls. */
2890 && check_sibcall_argument_overlap (after_args
, 0, 0))
2891 sibcall_failure
= 1;
2893 /* If a non-BLKmode value is returned at the most significant end
2894 of a register, shift the register right by the appropriate amount
2895 and update VALREG accordingly. BLKmode values are handled by the
2896 group load/store machinery below. */
2897 if (!structure_value_addr
2898 && !pcc_struct_value
2899 && TYPE_MODE (rettype
) != BLKmode
2900 && targetm
.calls
.return_in_msb (rettype
))
2902 if (shift_return_value (TYPE_MODE (rettype
), false, valreg
))
2903 sibcall_failure
= 1;
2904 valreg
= gen_rtx_REG (TYPE_MODE (rettype
), REGNO (valreg
));
2907 if (pass
&& (flags
& ECF_MALLOC
))
2909 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2912 /* The return value from a malloc-like function is a pointer. */
2913 if (TREE_CODE (rettype
) == POINTER_TYPE
)
2914 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
2916 emit_move_insn (temp
, valreg
);
2918 /* The return value from a malloc-like function can not alias
2920 last
= get_last_insn ();
2921 add_reg_note (last
, REG_NOALIAS
, temp
);
2923 /* Write out the sequence. */
2924 insns
= get_insns ();
2930 /* For calls to `setjmp', etc., inform
2931 function.c:setjmp_warnings that it should complain if
2932 nonvolatile values are live. For functions that cannot
2933 return, inform flow that control does not fall through. */
2935 if ((flags
& ECF_NORETURN
) || pass
== 0)
2937 /* The barrier must be emitted
2938 immediately after the CALL_INSN. Some ports emit more
2939 than just a CALL_INSN above, so we must search for it here. */
2941 rtx last
= get_last_insn ();
2942 while (!CALL_P (last
))
2944 last
= PREV_INSN (last
);
2945 /* There was no CALL_INSN? */
2946 gcc_assert (last
!= before_call
);
2949 emit_barrier_after (last
);
2951 /* Stack adjustments after a noreturn call are dead code.
2952 However when NO_DEFER_POP is in effect, we must preserve
2953 stack_pointer_delta. */
2954 if (inhibit_defer_pop
== 0)
2956 stack_pointer_delta
= old_stack_allocated
;
2957 pending_stack_adjust
= 0;
2961 /* If value type not void, return an rtx for the value. */
2963 if (TYPE_MODE (rettype
) == VOIDmode
2965 target
= const0_rtx
;
2966 else if (structure_value_addr
)
2968 if (target
== 0 || !MEM_P (target
))
2971 = gen_rtx_MEM (TYPE_MODE (rettype
),
2972 memory_address (TYPE_MODE (rettype
),
2973 structure_value_addr
));
2974 set_mem_attributes (target
, rettype
, 1);
2977 else if (pcc_struct_value
)
2979 /* This is the special C++ case where we need to
2980 know what the true target was. We take care to
2981 never use this value more than once in one expression. */
2982 target
= gen_rtx_MEM (TYPE_MODE (rettype
),
2983 copy_to_reg (valreg
));
2984 set_mem_attributes (target
, rettype
, 1);
2986 /* Handle calls that return values in multiple non-contiguous locations.
2987 The Irix 6 ABI has examples of this. */
2988 else if (GET_CODE (valreg
) == PARALLEL
)
2992 /* This will only be assigned once, so it can be readonly. */
2993 tree nt
= build_qualified_type (rettype
,
2994 (TYPE_QUALS (rettype
)
2995 | TYPE_QUAL_CONST
));
2997 target
= assign_temp (nt
, 0, 1, 1);
3000 if (! rtx_equal_p (target
, valreg
))
3001 emit_group_store (target
, valreg
, rettype
,
3002 int_size_in_bytes (rettype
));
3004 /* We can not support sibling calls for this case. */
3005 sibcall_failure
= 1;
3008 && GET_MODE (target
) == TYPE_MODE (rettype
)
3009 && GET_MODE (target
) == GET_MODE (valreg
))
3011 bool may_overlap
= false;
3013 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
3014 reg to a plain register. */
3015 if (!REG_P (target
) || HARD_REGISTER_P (target
))
3016 valreg
= avoid_likely_spilled_reg (valreg
);
3018 /* If TARGET is a MEM in the argument area, and we have
3019 saved part of the argument area, then we can't store
3020 directly into TARGET as it may get overwritten when we
3021 restore the argument save area below. Don't work too
3022 hard though and simply force TARGET to a register if it
3023 is a MEM; the optimizer is quite likely to sort it out. */
3024 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
3025 for (i
= 0; i
< num_actuals
; i
++)
3026 if (args
[i
].save_area
)
3033 target
= copy_to_reg (valreg
);
3036 /* TARGET and VALREG cannot be equal at this point
3037 because the latter would not have
3038 REG_FUNCTION_VALUE_P true, while the former would if
3039 it were referring to the same register.
3041 If they refer to the same register, this move will be
3042 a no-op, except when function inlining is being
3044 emit_move_insn (target
, valreg
);
3046 /* If we are setting a MEM, this code must be executed.
3047 Since it is emitted after the call insn, sibcall
3048 optimization cannot be performed in that case. */
3050 sibcall_failure
= 1;
3053 else if (TYPE_MODE (rettype
) == BLKmode
)
3056 if (GET_MODE (val
) != BLKmode
)
3057 val
= avoid_likely_spilled_reg (val
);
3058 target
= copy_blkmode_from_reg (target
, val
, rettype
);
3060 /* We can not support sibling calls for this case. */
3061 sibcall_failure
= 1;
3064 target
= copy_to_reg (avoid_likely_spilled_reg (valreg
));
3066 /* If we promoted this return value, make the proper SUBREG.
3067 TARGET might be const0_rtx here, so be careful. */
3069 && TYPE_MODE (rettype
) != BLKmode
3070 && GET_MODE (target
) != TYPE_MODE (rettype
))
3072 tree type
= rettype
;
3073 int unsignedp
= TYPE_UNSIGNED (type
);
3075 enum machine_mode pmode
;
3077 /* Ensure we promote as expected, and get the new unsignedness. */
3078 pmode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
3080 gcc_assert (GET_MODE (target
) == pmode
);
3082 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
3083 && (GET_MODE_SIZE (GET_MODE (target
))
3084 > GET_MODE_SIZE (TYPE_MODE (type
))))
3086 offset
= GET_MODE_SIZE (GET_MODE (target
))
3087 - GET_MODE_SIZE (TYPE_MODE (type
));
3088 if (! BYTES_BIG_ENDIAN
)
3089 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
3090 else if (! WORDS_BIG_ENDIAN
)
3091 offset
%= UNITS_PER_WORD
;
3094 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
3095 SUBREG_PROMOTED_VAR_P (target
) = 1;
3096 SUBREG_PROMOTED_UNSIGNED_SET (target
, unsignedp
);
3099 /* If size of args is variable or this was a constructor call for a stack
3100 argument, restore saved stack-pointer value. */
3102 if (old_stack_level
)
3104 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
3105 stack_pointer_delta
= old_stack_pointer_delta
;
3106 pending_stack_adjust
= old_pending_adj
;
3107 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
3108 stack_arg_under_construction
= old_stack_arg_under_construction
;
3109 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3110 stack_usage_map
= initial_stack_usage_map
;
3111 sibcall_failure
= 1;
3113 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
3115 #ifdef REG_PARM_STACK_SPACE
3117 restore_fixed_argument_area (save_area
, argblock
,
3118 high_to_save
, low_to_save
);
3121 /* If we saved any argument areas, restore them. */
3122 for (i
= 0; i
< num_actuals
; i
++)
3123 if (args
[i
].save_area
)
3125 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
3127 = gen_rtx_MEM (save_mode
,
3128 memory_address (save_mode
,
3129 XEXP (args
[i
].stack_slot
, 0)));
3131 if (save_mode
!= BLKmode
)
3132 emit_move_insn (stack_area
, args
[i
].save_area
);
3134 emit_block_move (stack_area
, args
[i
].save_area
,
3135 GEN_INT (args
[i
].locate
.size
.constant
),
3136 BLOCK_OP_CALL_PARM
);
3139 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3140 stack_usage_map
= initial_stack_usage_map
;
3143 /* If this was alloca, record the new stack level for nonlocal gotos.
3144 Check for the handler slots since we might not have a save area
3145 for non-local gotos. */
3147 if ((flags
& ECF_MAY_BE_ALLOCA
) && cfun
->nonlocal_goto_save_area
!= 0)
3148 update_nonlocal_goto_save_area ();
3150 /* Free up storage we no longer need. */
3151 for (i
= 0; i
< num_actuals
; ++i
)
3152 if (args
[i
].aligned_regs
)
3153 free (args
[i
].aligned_regs
);
3155 insns
= get_insns ();
3160 tail_call_insns
= insns
;
3162 /* Restore the pending stack adjustment now that we have
3163 finished generating the sibling call sequence. */
3165 pending_stack_adjust
= save_pending_stack_adjust
;
3166 stack_pointer_delta
= save_stack_pointer_delta
;
3168 /* Prepare arg structure for next iteration. */
3169 for (i
= 0; i
< num_actuals
; i
++)
3172 args
[i
].aligned_regs
= 0;
3176 sbitmap_free (stored_args_map
);
3180 normal_call_insns
= insns
;
3182 /* Verify that we've deallocated all the stack we used. */
3183 gcc_assert ((flags
& ECF_NORETURN
)
3184 || (old_stack_allocated
3185 == stack_pointer_delta
- pending_stack_adjust
));
3188 /* If something prevents making this a sibling call,
3189 zero out the sequence. */
3190 if (sibcall_failure
)
3191 tail_call_insns
= NULL_RTX
;
3196 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3197 arguments too, as argument area is now clobbered by the call. */
3198 if (tail_call_insns
)
3200 emit_insn (tail_call_insns
);
3201 crtl
->tail_call_emit
= true;
3204 emit_insn (normal_call_insns
);
3206 currently_expanding_call
--;
3208 if (stack_usage_map_buf
)
3209 free (stack_usage_map_buf
);
3214 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3215 this function's incoming arguments.
3217 At the start of RTL generation we know the only REG_EQUIV notes
3218 in the rtl chain are those for incoming arguments, so we can look
3219 for REG_EQUIV notes between the start of the function and the
3220 NOTE_INSN_FUNCTION_BEG.
3222 This is (slight) overkill. We could keep track of the highest
3223 argument we clobber and be more selective in removing notes, but it
3224 does not seem to be worth the effort. */
3227 fixup_tail_calls (void)
3231 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
3235 /* There are never REG_EQUIV notes for the incoming arguments
3236 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3238 && NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
)
3241 note
= find_reg_note (insn
, REG_EQUIV
, 0);
3243 remove_note (insn
, note
);
3244 note
= find_reg_note (insn
, REG_EQUIV
, 0);
3249 /* Traverse a list of TYPES and expand all complex types into their
3252 split_complex_types (tree types
)
3256 /* Before allocating memory, check for the common case of no complex. */
3257 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3259 tree type
= TREE_VALUE (p
);
3260 if (TREE_CODE (type
) == COMPLEX_TYPE
3261 && targetm
.calls
.split_complex_arg (type
))
3267 types
= copy_list (types
);
3269 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3271 tree complex_type
= TREE_VALUE (p
);
3273 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
3274 && targetm
.calls
.split_complex_arg (complex_type
))
3278 /* Rewrite complex type with component type. */
3279 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
3280 next
= TREE_CHAIN (p
);
3282 /* Add another component type for the imaginary part. */
3283 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
3284 TREE_CHAIN (p
) = imag
;
3285 TREE_CHAIN (imag
) = next
;
3287 /* Skip the newly created node. */
3295 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3296 The RETVAL parameter specifies whether return value needs to be saved, other
3297 parameters are documented in the emit_library_call function below. */
3300 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
3301 enum libcall_type fn_type
,
3302 enum machine_mode outmode
, int nargs
, va_list p
)
3304 /* Total size in bytes of all the stack-parms scanned so far. */
3305 struct args_size args_size
;
3306 /* Size of arguments before any adjustments (such as rounding). */
3307 struct args_size original_args_size
;
3310 /* Todo, choose the correct decl type of orgfun. Sadly this information
3311 isn't present here, so we default to native calling abi here. */
3312 tree fndecl ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
3313 tree fntype ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
3317 CUMULATIVE_ARGS args_so_far
;
3321 enum machine_mode mode
;
3324 struct locate_and_pad_arg_data locate
;
3328 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3329 rtx call_fusage
= 0;
3332 int pcc_struct_value
= 0;
3333 int struct_value_size
= 0;
3335 int reg_parm_stack_space
= 0;
3338 tree tfom
; /* type_for_mode (outmode, 0) */
3340 #ifdef REG_PARM_STACK_SPACE
3341 /* Define the boundary of the register parm stack space that needs to be
3343 int low_to_save
= 0, high_to_save
= 0;
3344 rtx save_area
= 0; /* Place that it is saved. */
3347 /* Size of the stack reserved for parameter registers. */
3348 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3349 char *initial_stack_usage_map
= stack_usage_map
;
3350 char *stack_usage_map_buf
= NULL
;
3352 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
3354 #ifdef REG_PARM_STACK_SPACE
3355 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3358 /* By default, library functions can not throw. */
3359 flags
= ECF_NOTHROW
;
3372 flags
|= ECF_NORETURN
;
3375 flags
= ECF_NORETURN
;
3377 case LCT_RETURNS_TWICE
:
3378 flags
= ECF_RETURNS_TWICE
;
3383 /* Ensure current function's preferred stack boundary is at least
3385 if (crtl
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3386 crtl
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3388 /* If this kind of value comes back in memory,
3389 decide where in memory it should come back. */
3390 if (outmode
!= VOIDmode
)
3392 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
3393 if (aggregate_value_p (tfom
, 0))
3395 #ifdef PCC_STATIC_STRUCT_RETURN
3397 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
3398 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3399 pcc_struct_value
= 1;
3401 value
= gen_reg_rtx (outmode
);
3402 #else /* not PCC_STATIC_STRUCT_RETURN */
3403 struct_value_size
= GET_MODE_SIZE (outmode
);
3404 if (value
!= 0 && MEM_P (value
))
3407 mem_value
= assign_temp (tfom
, 0, 1, 1);
3409 /* This call returns a big structure. */
3410 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
3414 tfom
= void_type_node
;
3416 /* ??? Unfinished: must pass the memory address as an argument. */
3418 /* Copy all the libcall-arguments out of the varargs data
3419 and into a vector ARGVEC.
3421 Compute how to pass each argument. We only support a very small subset
3422 of the full argument passing conventions to limit complexity here since
3423 library functions shouldn't have many args. */
3425 argvec
= XALLOCAVEC (struct arg
, nargs
+ 1);
3426 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3428 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3429 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3431 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0, nargs
);
3434 args_size
.constant
= 0;
3441 /* If there's a structure value address to be passed,
3442 either pass it in the special place, or pass it as an extra argument. */
3443 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
3445 rtx addr
= XEXP (mem_value
, 0);
3449 /* Make sure it is a reasonable operand for a move or push insn. */
3450 if (!REG_P (addr
) && !MEM_P (addr
)
3451 && ! (CONSTANT_P (addr
) && LEGITIMATE_CONSTANT_P (addr
)))
3452 addr
= force_operand (addr
, NULL_RTX
);
3454 argvec
[count
].value
= addr
;
3455 argvec
[count
].mode
= Pmode
;
3456 argvec
[count
].partial
= 0;
3458 argvec
[count
].reg
= targetm
.calls
.function_arg (&args_so_far
,
3459 Pmode
, NULL_TREE
, true);
3460 gcc_assert (targetm
.calls
.arg_partial_bytes (&args_so_far
, Pmode
,
3461 NULL_TREE
, 1) == 0);
3463 locate_and_pad_parm (Pmode
, NULL_TREE
,
3464 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3467 argvec
[count
].reg
!= 0,
3469 0, NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3471 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3472 || reg_parm_stack_space
> 0)
3473 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3475 targetm
.calls
.function_arg_advance (&args_so_far
, Pmode
, (tree
) 0, true);
3480 for (; count
< nargs
; count
++)
3482 rtx val
= va_arg (p
, rtx
);
3483 enum machine_mode mode
= (enum machine_mode
) va_arg (p
, int);
3485 /* We cannot convert the arg value to the mode the library wants here;
3486 must do it earlier where we know the signedness of the arg. */
3487 gcc_assert (mode
!= BLKmode
3488 && (GET_MODE (val
) == mode
|| GET_MODE (val
) == VOIDmode
));
3490 /* Make sure it is a reasonable operand for a move or push insn. */
3491 if (!REG_P (val
) && !MEM_P (val
)
3492 && ! (CONSTANT_P (val
) && LEGITIMATE_CONSTANT_P (val
)))
3493 val
= force_operand (val
, NULL_RTX
);
3495 if (pass_by_reference (&args_so_far
, mode
, NULL_TREE
, 1))
3499 = !reference_callee_copied (&args_so_far
, mode
, NULL_TREE
, 1);
3501 /* If this was a CONST function, it is now PURE since it now
3503 if (flags
& ECF_CONST
)
3505 flags
&= ~ECF_CONST
;
3509 if (MEM_P (val
) && !must_copy
)
3513 slot
= assign_temp (lang_hooks
.types
.type_for_mode (mode
, 0),
3515 emit_move_insn (slot
, val
);
3518 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3519 gen_rtx_USE (VOIDmode
, slot
),
3522 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3523 gen_rtx_CLOBBER (VOIDmode
,
3528 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3531 argvec
[count
].value
= val
;
3532 argvec
[count
].mode
= mode
;
3534 argvec
[count
].reg
= targetm
.calls
.function_arg (&args_so_far
, mode
,
3537 argvec
[count
].partial
3538 = targetm
.calls
.arg_partial_bytes (&args_so_far
, mode
, NULL_TREE
, 1);
3540 locate_and_pad_parm (mode
, NULL_TREE
,
3541 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3544 argvec
[count
].reg
!= 0,
3546 argvec
[count
].partial
,
3547 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3549 gcc_assert (!argvec
[count
].locate
.size
.var
);
3551 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3552 || reg_parm_stack_space
> 0)
3553 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3555 targetm
.calls
.function_arg_advance (&args_so_far
, mode
, (tree
) 0, true);
3558 /* If this machine requires an external definition for library
3559 functions, write one out. */
3560 assemble_external_libcall (fun
);
3562 original_args_size
= args_size
;
3563 args_size
.constant
= (((args_size
.constant
3564 + stack_pointer_delta
3568 - stack_pointer_delta
);
3570 args_size
.constant
= MAX (args_size
.constant
,
3571 reg_parm_stack_space
);
3573 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3574 args_size
.constant
-= reg_parm_stack_space
;
3576 if (args_size
.constant
> crtl
->outgoing_args_size
)
3577 crtl
->outgoing_args_size
= args_size
.constant
;
3579 if (flag_stack_usage
&& !ACCUMULATE_OUTGOING_ARGS
)
3581 int pushed
= args_size
.constant
+ pending_stack_adjust
;
3582 if (pushed
> current_function_pushed_stack_size
)
3583 current_function_pushed_stack_size
= pushed
;
3586 if (ACCUMULATE_OUTGOING_ARGS
)
3588 /* Since the stack pointer will never be pushed, it is possible for
3589 the evaluation of a parm to clobber something we have already
3590 written to the stack. Since most function calls on RISC machines
3591 do not use the stack, this is uncommon, but must work correctly.
3593 Therefore, we save any area of the stack that was already written
3594 and that we are using. Here we set up to do this by making a new
3595 stack usage map from the old one.
3597 Another approach might be to try to reorder the argument
3598 evaluations to avoid this conflicting stack usage. */
3600 needed
= args_size
.constant
;
3602 /* Since we will be writing into the entire argument area, the
3603 map must be allocated for its entire size, not just the part that
3604 is the responsibility of the caller. */
3605 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3606 needed
+= reg_parm_stack_space
;
3608 #ifdef ARGS_GROW_DOWNWARD
3609 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3612 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3615 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
3616 stack_usage_map
= stack_usage_map_buf
;
3618 if (initial_highest_arg_in_use
)
3619 memcpy (stack_usage_map
, initial_stack_usage_map
,
3620 initial_highest_arg_in_use
);
3622 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3623 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3624 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3627 /* We must be careful to use virtual regs before they're instantiated,
3628 and real regs afterwards. Loop optimization, for example, can create
3629 new libcalls after we've instantiated the virtual regs, and if we
3630 use virtuals anyway, they won't match the rtl patterns. */
3632 if (virtuals_instantiated
)
3633 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3635 argblock
= virtual_outgoing_args_rtx
;
3640 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3643 /* If we push args individually in reverse order, perform stack alignment
3644 before the first push (the last arg). */
3645 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3646 anti_adjust_stack (GEN_INT (args_size
.constant
3647 - original_args_size
.constant
));
3649 if (PUSH_ARGS_REVERSED
)
3660 #ifdef REG_PARM_STACK_SPACE
3661 if (ACCUMULATE_OUTGOING_ARGS
)
3663 /* The argument list is the property of the called routine and it
3664 may clobber it. If the fixed area has been used for previous
3665 parameters, we must save and restore it. */
3666 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
3667 &low_to_save
, &high_to_save
);
3671 /* Push the args that need to be pushed. */
3673 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3674 are to be pushed. */
3675 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3677 enum machine_mode mode
= argvec
[argnum
].mode
;
3678 rtx val
= argvec
[argnum
].value
;
3679 rtx reg
= argvec
[argnum
].reg
;
3680 int partial
= argvec
[argnum
].partial
;
3681 unsigned int parm_align
= argvec
[argnum
].locate
.boundary
;
3682 int lower_bound
= 0, upper_bound
= 0, i
;
3684 if (! (reg
!= 0 && partial
== 0))
3686 if (ACCUMULATE_OUTGOING_ARGS
)
3688 /* If this is being stored into a pre-allocated, fixed-size,
3689 stack area, save any previous data at that location. */
3691 #ifdef ARGS_GROW_DOWNWARD
3692 /* stack_slot is negative, but we want to index stack_usage_map
3693 with positive values. */
3694 upper_bound
= -argvec
[argnum
].locate
.slot_offset
.constant
+ 1;
3695 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
3697 lower_bound
= argvec
[argnum
].locate
.slot_offset
.constant
;
3698 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
3702 /* Don't worry about things in the fixed argument area;
3703 it has already been saved. */
3704 if (i
< reg_parm_stack_space
)
3705 i
= reg_parm_stack_space
;
3706 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
3709 if (i
< upper_bound
)
3711 /* We need to make a save area. */
3713 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
3714 enum machine_mode save_mode
3715 = mode_for_size (size
, MODE_INT
, 1);
3717 = plus_constant (argblock
,
3718 argvec
[argnum
].locate
.offset
.constant
);
3720 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
3722 if (save_mode
== BLKmode
)
3724 argvec
[argnum
].save_area
3725 = assign_stack_temp (BLKmode
,
3726 argvec
[argnum
].locate
.size
.constant
,
3729 emit_block_move (validize_mem (argvec
[argnum
].save_area
),
3731 GEN_INT (argvec
[argnum
].locate
.size
.constant
),
3732 BLOCK_OP_CALL_PARM
);
3736 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3738 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3743 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, parm_align
,
3744 partial
, reg
, 0, argblock
,
3745 GEN_INT (argvec
[argnum
].locate
.offset
.constant
),
3746 reg_parm_stack_space
,
3747 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
));
3749 /* Now mark the segment we just used. */
3750 if (ACCUMULATE_OUTGOING_ARGS
)
3751 for (i
= lower_bound
; i
< upper_bound
; i
++)
3752 stack_usage_map
[i
] = 1;
3756 if ((flags
& ECF_CONST
)
3757 || ((flags
& ECF_PURE
) && ACCUMULATE_OUTGOING_ARGS
))
3761 /* Indicate argument access so that alias.c knows that these
3764 use
= plus_constant (argblock
,
3765 argvec
[argnum
].locate
.offset
.constant
);
3767 /* When arguments are pushed, trying to tell alias.c where
3768 exactly this argument is won't work, because the
3769 auto-increment causes confusion. So we merely indicate
3770 that we access something with a known mode somewhere on
3772 use
= gen_rtx_PLUS (Pmode
, virtual_outgoing_args_rtx
,
3773 gen_rtx_SCRATCH (Pmode
));
3774 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
3775 use
= gen_rtx_USE (VOIDmode
, use
);
3776 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
3781 /* If we pushed args in forward order, perform stack alignment
3782 after pushing the last arg. */
3783 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3784 anti_adjust_stack (GEN_INT (args_size
.constant
3785 - original_args_size
.constant
));
3787 if (PUSH_ARGS_REVERSED
)
3792 fun
= prepare_call_address (NULL
, fun
, NULL
, &call_fusage
, 0, 0);
3794 /* Now load any reg parms into their regs. */
3796 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3797 are to be pushed. */
3798 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3800 enum machine_mode mode
= argvec
[argnum
].mode
;
3801 rtx val
= argvec
[argnum
].value
;
3802 rtx reg
= argvec
[argnum
].reg
;
3803 int partial
= argvec
[argnum
].partial
;
3805 /* Handle calls that pass values in multiple non-contiguous
3806 locations. The PA64 has examples of this for library calls. */
3807 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3808 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
3809 else if (reg
!= 0 && partial
== 0)
3810 emit_move_insn (reg
, val
);
3815 /* Any regs containing parms remain in use through the call. */
3816 for (count
= 0; count
< nargs
; count
++)
3818 rtx reg
= argvec
[count
].reg
;
3819 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3820 use_group_regs (&call_fusage
, reg
);
3823 int partial
= argvec
[count
].partial
;
3827 gcc_assert (partial
% UNITS_PER_WORD
== 0);
3828 nregs
= partial
/ UNITS_PER_WORD
;
3829 use_regs (&call_fusage
, REGNO (reg
), nregs
);
3832 use_reg (&call_fusage
, reg
);
3836 /* Pass the function the address in which to return a structure value. */
3837 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
3839 emit_move_insn (struct_value
,
3841 force_operand (XEXP (mem_value
, 0),
3843 if (REG_P (struct_value
))
3844 use_reg (&call_fusage
, struct_value
);
3847 /* Don't allow popping to be deferred, since then
3848 cse'ing of library calls could delete a call and leave the pop. */
3850 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
3851 ? hard_libcall_value (outmode
, orgfun
) : NULL_RTX
);
3853 /* Stack must be properly aligned now. */
3854 gcc_assert (!(stack_pointer_delta
3855 & (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1)));
3857 before_call
= get_last_insn ();
3859 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3860 will set inhibit_defer_pop to that value. */
3861 /* The return type is needed to decide how many bytes the function pops.
3862 Signedness plays no role in that, so for simplicity, we pretend it's
3863 always signed. We also assume that the list of arguments passed has
3864 no impact, so we pretend it is unknown. */
3866 emit_call_1 (fun
, NULL
,
3867 get_identifier (XSTR (orgfun
, 0)),
3868 build_function_type (tfom
, NULL_TREE
),
3869 original_args_size
.constant
, args_size
.constant
,
3871 targetm
.calls
.function_arg (&args_so_far
,
3872 VOIDmode
, void_type_node
, true),
3874 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, & args_so_far
);
3876 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
3877 that it should complain if nonvolatile values are live. For
3878 functions that cannot return, inform flow that control does not
3881 if (flags
& ECF_NORETURN
)
3883 /* The barrier note must be emitted
3884 immediately after the CALL_INSN. Some ports emit more than
3885 just a CALL_INSN above, so we must search for it here. */
3887 rtx last
= get_last_insn ();
3888 while (!CALL_P (last
))
3890 last
= PREV_INSN (last
);
3891 /* There was no CALL_INSN? */
3892 gcc_assert (last
!= before_call
);
3895 emit_barrier_after (last
);
3898 /* Now restore inhibit_defer_pop to its actual original value. */
3903 /* Copy the value to the right place. */
3904 if (outmode
!= VOIDmode
&& retval
)
3910 if (value
!= mem_value
)
3911 emit_move_insn (value
, mem_value
);
3913 else if (GET_CODE (valreg
) == PARALLEL
)
3916 value
= gen_reg_rtx (outmode
);
3917 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
3921 /* Convert to the proper mode if a promotion has been active. */
3922 if (GET_MODE (valreg
) != outmode
)
3924 int unsignedp
= TYPE_UNSIGNED (tfom
);
3926 gcc_assert (promote_function_mode (tfom
, outmode
, &unsignedp
,
3927 fndecl
? TREE_TYPE (fndecl
) : fntype
, 1)
3928 == GET_MODE (valreg
));
3929 valreg
= convert_modes (outmode
, GET_MODE (valreg
), valreg
, 0);
3933 emit_move_insn (value
, valreg
);
3939 if (ACCUMULATE_OUTGOING_ARGS
)
3941 #ifdef REG_PARM_STACK_SPACE
3943 restore_fixed_argument_area (save_area
, argblock
,
3944 high_to_save
, low_to_save
);
3947 /* If we saved any argument areas, restore them. */
3948 for (count
= 0; count
< nargs
; count
++)
3949 if (argvec
[count
].save_area
)
3951 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
3952 rtx adr
= plus_constant (argblock
,
3953 argvec
[count
].locate
.offset
.constant
);
3954 rtx stack_area
= gen_rtx_MEM (save_mode
,
3955 memory_address (save_mode
, adr
));
3957 if (save_mode
== BLKmode
)
3958 emit_block_move (stack_area
,
3959 validize_mem (argvec
[count
].save_area
),
3960 GEN_INT (argvec
[count
].locate
.size
.constant
),
3961 BLOCK_OP_CALL_PARM
);
3963 emit_move_insn (stack_area
, argvec
[count
].save_area
);
3966 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3967 stack_usage_map
= initial_stack_usage_map
;
3970 if (stack_usage_map_buf
)
3971 free (stack_usage_map_buf
);
3977 /* Output a library call to function FUN (a SYMBOL_REF rtx)
3978 (emitting the queue unless NO_QUEUE is nonzero),
3979 for a value of mode OUTMODE,
3980 with NARGS different arguments, passed as alternating rtx values
3981 and machine_modes to convert them to.
3983 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
3984 `const' calls, LCT_PURE for `pure' calls, or other LCT_ value for
3985 other types of library calls. */
3988 emit_library_call (rtx orgfun
, enum libcall_type fn_type
,
3989 enum machine_mode outmode
, int nargs
, ...)
3993 va_start (p
, nargs
);
3994 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
3998 /* Like emit_library_call except that an extra argument, VALUE,
3999 comes second and says where to store the result.
4000 (If VALUE is zero, this function chooses a convenient way
4001 to return the value.
4003 This function returns an rtx for where the value is to be found.
4004 If VALUE is nonzero, VALUE is returned. */
4007 emit_library_call_value (rtx orgfun
, rtx value
,
4008 enum libcall_type fn_type
,
4009 enum machine_mode outmode
, int nargs
, ...)
4014 va_start (p
, nargs
);
4015 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
4022 /* Store a single argument for a function call
4023 into the register or memory area where it must be passed.
4024 *ARG describes the argument value and where to pass it.
4026 ARGBLOCK is the address of the stack-block for all the arguments,
4027 or 0 on a machine where arguments are pushed individually.
4029 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4030 so must be careful about how the stack is used.
4032 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4033 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4034 that we need not worry about saving and restoring the stack.
4036 FNDECL is the declaration of the function we are calling.
4038 Return nonzero if this arg should cause sibcall failure,
4042 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
4043 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
4045 tree pval
= arg
->tree_value
;
4049 int i
, lower_bound
= 0, upper_bound
= 0;
4050 int sibcall_failure
= 0;
4052 if (TREE_CODE (pval
) == ERROR_MARK
)
4055 /* Push a new temporary level for any temporaries we make for
4059 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4061 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4062 save any previous data at that location. */
4063 if (argblock
&& ! variable_size
&& arg
->stack
)
4065 #ifdef ARGS_GROW_DOWNWARD
4066 /* stack_slot is negative, but we want to index stack_usage_map
4067 with positive values. */
4068 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4069 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4073 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
4075 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4076 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4080 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
4084 /* Don't worry about things in the fixed argument area;
4085 it has already been saved. */
4086 if (i
< reg_parm_stack_space
)
4087 i
= reg_parm_stack_space
;
4088 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
4091 if (i
< upper_bound
)
4093 /* We need to make a save area. */
4094 unsigned int size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
4095 enum machine_mode save_mode
= mode_for_size (size
, MODE_INT
, 1);
4096 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
4097 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
4099 if (save_mode
== BLKmode
)
4101 tree ot
= TREE_TYPE (arg
->tree_value
);
4102 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4103 | TYPE_QUAL_CONST
));
4105 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4106 preserve_temp_slots (arg
->save_area
);
4107 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4108 GEN_INT (arg
->locate
.size
.constant
),
4109 BLOCK_OP_CALL_PARM
);
4113 arg
->save_area
= gen_reg_rtx (save_mode
);
4114 emit_move_insn (arg
->save_area
, stack_area
);
4120 /* If this isn't going to be placed on both the stack and in registers,
4121 set up the register and number of words. */
4122 if (! arg
->pass_on_stack
)
4124 if (flags
& ECF_SIBCALL
)
4125 reg
= arg
->tail_call_reg
;
4128 partial
= arg
->partial
;
4131 /* Being passed entirely in a register. We shouldn't be called in
4133 gcc_assert (reg
== 0 || partial
!= 0);
4135 /* If this arg needs special alignment, don't load the registers
4137 if (arg
->n_aligned_regs
!= 0)
4140 /* If this is being passed partially in a register, we can't evaluate
4141 it directly into its stack slot. Otherwise, we can. */
4142 if (arg
->value
== 0)
4144 /* stack_arg_under_construction is nonzero if a function argument is
4145 being evaluated directly into the outgoing argument list and
4146 expand_call must take special action to preserve the argument list
4147 if it is called recursively.
4149 For scalar function arguments stack_usage_map is sufficient to
4150 determine which stack slots must be saved and restored. Scalar
4151 arguments in general have pass_on_stack == 0.
4153 If this argument is initialized by a function which takes the
4154 address of the argument (a C++ constructor or a C function
4155 returning a BLKmode structure), then stack_usage_map is
4156 insufficient and expand_call must push the stack around the
4157 function call. Such arguments have pass_on_stack == 1.
4159 Note that it is always safe to set stack_arg_under_construction,
4160 but this generates suboptimal code if set when not needed. */
4162 if (arg
->pass_on_stack
)
4163 stack_arg_under_construction
++;
4165 arg
->value
= expand_expr (pval
,
4167 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4168 ? NULL_RTX
: arg
->stack
,
4169 VOIDmode
, EXPAND_STACK_PARM
);
4171 /* If we are promoting object (or for any other reason) the mode
4172 doesn't agree, convert the mode. */
4174 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4175 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4176 arg
->value
, arg
->unsignedp
);
4178 if (arg
->pass_on_stack
)
4179 stack_arg_under_construction
--;
4182 /* Check for overlap with already clobbered argument area. */
4183 if ((flags
& ECF_SIBCALL
)
4184 && MEM_P (arg
->value
)
4185 && mem_overlaps_already_clobbered_arg_p (XEXP (arg
->value
, 0),
4186 arg
->locate
.size
.constant
))
4187 sibcall_failure
= 1;
4189 /* Don't allow anything left on stack from computation
4190 of argument to alloca. */
4191 if (flags
& ECF_MAY_BE_ALLOCA
)
4192 do_pending_stack_adjust ();
4194 if (arg
->value
== arg
->stack
)
4195 /* If the value is already in the stack slot, we are done. */
4197 else if (arg
->mode
!= BLKmode
)
4200 unsigned int parm_align
;
4202 /* Argument is a scalar, not entirely passed in registers.
4203 (If part is passed in registers, arg->partial says how much
4204 and emit_push_insn will take care of putting it there.)
4206 Push it, and if its size is less than the
4207 amount of space allocated to it,
4208 also bump stack pointer by the additional space.
4209 Note that in C the default argument promotions
4210 will prevent such mismatches. */
4212 size
= GET_MODE_SIZE (arg
->mode
);
4213 /* Compute how much space the push instruction will push.
4214 On many machines, pushing a byte will advance the stack
4215 pointer by a halfword. */
4216 #ifdef PUSH_ROUNDING
4217 size
= PUSH_ROUNDING (size
);
4221 /* Compute how much space the argument should get:
4222 round up to a multiple of the alignment for arguments. */
4223 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4224 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4225 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4226 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4228 /* Compute the alignment of the pushed argument. */
4229 parm_align
= arg
->locate
.boundary
;
4230 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4232 int pad
= used
- size
;
4235 unsigned int pad_align
= (pad
& -pad
) * BITS_PER_UNIT
;
4236 parm_align
= MIN (parm_align
, pad_align
);
4240 /* This isn't already where we want it on the stack, so put it there.
4241 This can either be done with push or copy insns. */
4242 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
,
4243 parm_align
, partial
, reg
, used
- size
, argblock
,
4244 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4245 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4247 /* Unless this is a partially-in-register argument, the argument is now
4250 arg
->value
= arg
->stack
;
4254 /* BLKmode, at least partly to be pushed. */
4256 unsigned int parm_align
;
4260 /* Pushing a nonscalar.
4261 If part is passed in registers, PARTIAL says how much
4262 and emit_push_insn will take care of putting it there. */
4264 /* Round its size up to a multiple
4265 of the allocation unit for arguments. */
4267 if (arg
->locate
.size
.var
!= 0)
4270 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
4274 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4275 for BLKmode is careful to avoid it. */
4276 excess
= (arg
->locate
.size
.constant
4277 - int_size_in_bytes (TREE_TYPE (pval
))
4279 size_rtx
= expand_expr (size_in_bytes (TREE_TYPE (pval
)),
4280 NULL_RTX
, TYPE_MODE (sizetype
),
4284 parm_align
= arg
->locate
.boundary
;
4286 /* When an argument is padded down, the block is aligned to
4287 PARM_BOUNDARY, but the actual argument isn't. */
4288 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4290 if (arg
->locate
.size
.var
)
4291 parm_align
= BITS_PER_UNIT
;
4294 unsigned int excess_align
= (excess
& -excess
) * BITS_PER_UNIT
;
4295 parm_align
= MIN (parm_align
, excess_align
);
4299 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
4301 /* emit_push_insn might not work properly if arg->value and
4302 argblock + arg->locate.offset areas overlap. */
4306 if (XEXP (x
, 0) == crtl
->args
.internal_arg_pointer
4307 || (GET_CODE (XEXP (x
, 0)) == PLUS
4308 && XEXP (XEXP (x
, 0), 0) ==
4309 crtl
->args
.internal_arg_pointer
4310 && CONST_INT_P (XEXP (XEXP (x
, 0), 1))))
4312 if (XEXP (x
, 0) != crtl
->args
.internal_arg_pointer
)
4313 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4315 /* expand_call should ensure this. */
4316 gcc_assert (!arg
->locate
.offset
.var
4317 && arg
->locate
.size
.var
== 0
4318 && CONST_INT_P (size_rtx
));
4320 if (arg
->locate
.offset
.constant
> i
)
4322 if (arg
->locate
.offset
.constant
< i
+ INTVAL (size_rtx
))
4323 sibcall_failure
= 1;
4325 else if (arg
->locate
.offset
.constant
< i
)
4327 /* Use arg->locate.size.constant instead of size_rtx
4328 because we only care about the part of the argument
4330 if (i
< (arg
->locate
.offset
.constant
4331 + arg
->locate
.size
.constant
))
4332 sibcall_failure
= 1;
4336 /* Even though they appear to be at the same location,
4337 if part of the outgoing argument is in registers,
4338 they aren't really at the same location. Check for
4339 this by making sure that the incoming size is the
4340 same as the outgoing size. */
4341 if (arg
->locate
.size
.constant
!= INTVAL (size_rtx
))
4342 sibcall_failure
= 1;
4347 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4348 parm_align
, partial
, reg
, excess
, argblock
,
4349 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4350 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4352 /* Unless this is a partially-in-register argument, the argument is now
4355 ??? Unlike the case above, in which we want the actual
4356 address of the data, so that we can load it directly into a
4357 register, here we want the address of the stack slot, so that
4358 it's properly aligned for word-by-word copying or something
4359 like that. It's not clear that this is always correct. */
4361 arg
->value
= arg
->stack_slot
;
4364 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
4366 tree type
= TREE_TYPE (arg
->tree_value
);
4368 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
4369 int_size_in_bytes (type
));
4372 /* Mark all slots this store used. */
4373 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
4374 && argblock
&& ! variable_size
&& arg
->stack
)
4375 for (i
= lower_bound
; i
< upper_bound
; i
++)
4376 stack_usage_map
[i
] = 1;
4378 /* Once we have pushed something, pops can't safely
4379 be deferred during the rest of the arguments. */
4382 /* Free any temporary slots made in processing this argument. Show
4383 that we might have taken the address of something and pushed that
4385 preserve_temp_slots (NULL_RTX
);
4389 return sibcall_failure
;
4392 /* Nonzero if we do not know how to pass TYPE solely in registers. */
4395 must_pass_in_stack_var_size (enum machine_mode mode ATTRIBUTE_UNUSED
,
4401 /* If the type has variable size... */
4402 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4405 /* If the type is marked as addressable (it is required
4406 to be constructed into the stack)... */
4407 if (TREE_ADDRESSABLE (type
))
4413 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
4414 takes trailing padding of a structure into account. */
4415 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
4418 must_pass_in_stack_var_size_or_pad (enum machine_mode mode
, const_tree type
)
4423 /* If the type has variable size... */
4424 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4427 /* If the type is marked as addressable (it is required
4428 to be constructed into the stack)... */
4429 if (TREE_ADDRESSABLE (type
))
4432 /* If the padding and mode of the type is such that a copy into
4433 a register would put it into the wrong part of the register. */
4435 && int_size_in_bytes (type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
4436 && (FUNCTION_ARG_PADDING (mode
, type
)
4437 == (BYTES_BIG_ENDIAN
? upward
: downward
)))