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
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 2, 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 COPYING. If not, write to the Free
20 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
25 #include "coretypes.h"
40 #include "langhooks.h"
46 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
47 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
49 /* Data structure and subroutines used within expand_call. */
53 /* Tree node for this argument. */
55 /* Mode for value; TYPE_MODE unless promoted. */
56 enum machine_mode mode
;
57 /* Current RTL value for argument, or 0 if it isn't precomputed. */
59 /* Initially-compute RTL value for argument; only for const functions. */
61 /* Register to pass this argument in, 0 if passed on stack, or an
62 PARALLEL if the arg is to be copied into multiple non-contiguous
65 /* Register to pass this argument in when generating tail call sequence.
66 This is not the same register as for normal calls on machines with
69 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
70 form for emit_group_move. */
72 /* If REG was promoted from the actual mode of the argument expression,
73 indicates whether the promotion is sign- or zero-extended. */
75 /* Number of bytes to put in registers. 0 means put the whole arg
76 in registers. Also 0 if not passed in registers. */
78 /* Nonzero if argument must be passed on stack.
79 Note that some arguments may be passed on the stack
80 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
81 pass_on_stack identifies arguments that *cannot* go in registers. */
83 /* Some fields packaged up for locate_and_pad_parm. */
84 struct locate_and_pad_arg_data locate
;
85 /* Location on the stack at which parameter should be stored. The store
86 has already been done if STACK == VALUE. */
88 /* Location on the stack of the start of this argument slot. This can
89 differ from STACK if this arg pads downward. This location is known
90 to be aligned to FUNCTION_ARG_BOUNDARY. */
92 /* Place that this stack area has been saved, if needed. */
94 /* If an argument's alignment does not permit direct copying into registers,
95 copy in smaller-sized pieces into pseudos. These are stored in a
96 block pointed to by this field. The next field says how many
97 word-sized pseudos we made. */
102 /* A vector of one char per byte of stack space. A byte if nonzero if
103 the corresponding stack location has been used.
104 This vector is used to prevent a function call within an argument from
105 clobbering any stack already set up. */
106 static char *stack_usage_map
;
108 /* Size of STACK_USAGE_MAP. */
109 static int highest_outgoing_arg_in_use
;
111 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
112 stack location's tail call argument has been already stored into the stack.
113 This bitmap is used to prevent sibling call optimization if function tries
114 to use parent's incoming argument slots when they have been already
115 overwritten with tail call arguments. */
116 static sbitmap stored_args_map
;
118 /* stack_arg_under_construction is nonzero when an argument may be
119 initialized with a constructor call (including a C function that
120 returns a BLKmode struct) and expand_call must take special action
121 to make sure the object being constructed does not overlap the
122 argument list for the constructor call. */
123 static int stack_arg_under_construction
;
125 static void emit_call_1 (rtx
, tree
, tree
, tree
, HOST_WIDE_INT
, HOST_WIDE_INT
,
126 HOST_WIDE_INT
, rtx
, rtx
, int, rtx
, int,
128 static void precompute_register_parameters (int, struct arg_data
*, int *);
129 static int store_one_arg (struct arg_data
*, rtx
, int, int, int);
130 static void store_unaligned_arguments_into_pseudos (struct arg_data
*, int);
131 static int finalize_must_preallocate (int, int, struct arg_data
*,
133 static void precompute_arguments (int, int, struct arg_data
*);
134 static int compute_argument_block_size (int, struct args_size
*, int);
135 static void initialize_argument_information (int, struct arg_data
*,
136 struct args_size
*, int,
138 tree
, CUMULATIVE_ARGS
*, int,
139 rtx
*, int *, int *, int *,
141 static void compute_argument_addresses (struct arg_data
*, rtx
, int);
142 static rtx
rtx_for_function_call (tree
, tree
);
143 static void load_register_parameters (struct arg_data
*, int, rtx
*, int,
145 static rtx
emit_library_call_value_1 (int, rtx
, rtx
, enum libcall_type
,
146 enum machine_mode
, int, va_list);
147 static int special_function_p (tree
, int);
148 static int check_sibcall_argument_overlap_1 (rtx
);
149 static int check_sibcall_argument_overlap (rtx
, struct arg_data
*, int);
151 static int combine_pending_stack_adjustment_and_call (int, struct args_size
*,
153 static tree
split_complex_types (tree
);
155 #ifdef REG_PARM_STACK_SPACE
156 static rtx
save_fixed_argument_area (int, rtx
, int *, int *);
157 static void restore_fixed_argument_area (rtx
, rtx
, int, int);
160 /* Force FUNEXP into a form suitable for the address of a CALL,
161 and return that as an rtx. Also load the static chain register
162 if FNDECL is a nested function.
164 CALL_FUSAGE points to a variable holding the prospective
165 CALL_INSN_FUNCTION_USAGE information. */
168 prepare_call_address (rtx funexp
, rtx static_chain_value
,
169 rtx
*call_fusage
, int reg_parm_seen
, int sibcallp
)
171 /* Make a valid memory address and copy constants through pseudo-regs,
172 but not for a constant address if -fno-function-cse. */
173 if (GET_CODE (funexp
) != SYMBOL_REF
)
174 /* If we are using registers for parameters, force the
175 function address into a register now. */
176 funexp
= ((SMALL_REGISTER_CLASSES
&& reg_parm_seen
)
177 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
178 : memory_address (FUNCTION_MODE
, funexp
));
181 #ifndef NO_FUNCTION_CSE
182 if (optimize
&& ! flag_no_function_cse
)
183 funexp
= force_reg (Pmode
, funexp
);
187 if (static_chain_value
!= 0)
189 static_chain_value
= convert_memory_address (Pmode
, static_chain_value
);
190 emit_move_insn (static_chain_rtx
, static_chain_value
);
192 if (REG_P (static_chain_rtx
))
193 use_reg (call_fusage
, static_chain_rtx
);
199 /* Generate instructions to call function FUNEXP,
200 and optionally pop the results.
201 The CALL_INSN is the first insn generated.
203 FNDECL is the declaration node of the function. This is given to the
204 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
206 FUNTYPE is the data type of the function. This is given to the macro
207 RETURN_POPS_ARGS to determine whether this function pops its own args.
208 We used to allow an identifier for library functions, but that doesn't
209 work when the return type is an aggregate type and the calling convention
210 says that the pointer to this aggregate is to be popped by the callee.
212 STACK_SIZE is the number of bytes of arguments on the stack,
213 ROUNDED_STACK_SIZE is that number rounded up to
214 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
215 both to put into the call insn and to generate explicit popping
218 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
219 It is zero if this call doesn't want a structure value.
221 NEXT_ARG_REG is the rtx that results from executing
222 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
223 just after all the args have had their registers assigned.
224 This could be whatever you like, but normally it is the first
225 arg-register beyond those used for args in this call,
226 or 0 if all the arg-registers are used in this call.
227 It is passed on to `gen_call' so you can put this info in the call insn.
229 VALREG is a hard register in which a value is returned,
230 or 0 if the call does not return a value.
232 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
233 the args to this call were processed.
234 We restore `inhibit_defer_pop' to that value.
236 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
237 denote registers used by the called function. */
240 emit_call_1 (rtx funexp
, tree fntree
, tree fndecl ATTRIBUTE_UNUSED
,
241 tree funtype ATTRIBUTE_UNUSED
,
242 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED
,
243 HOST_WIDE_INT rounded_stack_size
,
244 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED
,
245 rtx next_arg_reg ATTRIBUTE_UNUSED
, rtx valreg
,
246 int old_inhibit_defer_pop
, rtx call_fusage
, int ecf_flags
,
247 CUMULATIVE_ARGS
*args_so_far ATTRIBUTE_UNUSED
)
249 rtx rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
251 int already_popped
= 0;
252 HOST_WIDE_INT n_popped
= RETURN_POPS_ARGS (fndecl
, funtype
, stack_size
);
253 #if defined (HAVE_call) && defined (HAVE_call_value)
254 rtx struct_value_size_rtx
;
255 struct_value_size_rtx
= GEN_INT (struct_value_size
);
258 #ifdef CALL_POPS_ARGS
259 n_popped
+= CALL_POPS_ARGS (* args_so_far
);
262 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
263 and we don't want to load it into a register as an optimization,
264 because prepare_call_address already did it if it should be done. */
265 if (GET_CODE (funexp
) != SYMBOL_REF
)
266 funexp
= memory_address (FUNCTION_MODE
, funexp
);
268 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
269 if ((ecf_flags
& ECF_SIBCALL
)
270 && HAVE_sibcall_pop
&& HAVE_sibcall_value_pop
271 && (n_popped
> 0 || stack_size
== 0))
273 rtx n_pop
= GEN_INT (n_popped
);
276 /* If this subroutine pops its own args, record that in the call insn
277 if possible, for the sake of frame pointer elimination. */
280 pat
= GEN_SIBCALL_VALUE_POP (valreg
,
281 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
282 rounded_stack_size_rtx
, next_arg_reg
,
285 pat
= GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
286 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
288 emit_call_insn (pat
);
294 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
295 /* If the target has "call" or "call_value" insns, then prefer them
296 if no arguments are actually popped. If the target does not have
297 "call" or "call_value" insns, then we must use the popping versions
298 even if the call has no arguments to pop. */
299 #if defined (HAVE_call) && defined (HAVE_call_value)
300 if (HAVE_call
&& HAVE_call_value
&& HAVE_call_pop
&& HAVE_call_value_pop
301 && n_popped
> 0 && ! (ecf_flags
& ECF_SP_DEPRESSED
))
303 if (HAVE_call_pop
&& HAVE_call_value_pop
)
306 rtx n_pop
= GEN_INT (n_popped
);
309 /* If this subroutine pops its own args, record that in the call insn
310 if possible, for the sake of frame pointer elimination. */
313 pat
= GEN_CALL_VALUE_POP (valreg
,
314 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
315 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
317 pat
= GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
318 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
320 emit_call_insn (pat
);
326 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
327 if ((ecf_flags
& ECF_SIBCALL
)
328 && HAVE_sibcall
&& HAVE_sibcall_value
)
331 emit_call_insn (GEN_SIBCALL_VALUE (valreg
,
332 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
333 rounded_stack_size_rtx
,
334 next_arg_reg
, NULL_RTX
));
336 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
337 rounded_stack_size_rtx
, next_arg_reg
,
338 struct_value_size_rtx
));
343 #if defined (HAVE_call) && defined (HAVE_call_value)
344 if (HAVE_call
&& HAVE_call_value
)
347 emit_call_insn (GEN_CALL_VALUE (valreg
,
348 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
349 rounded_stack_size_rtx
, next_arg_reg
,
352 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
353 rounded_stack_size_rtx
, next_arg_reg
,
354 struct_value_size_rtx
));
360 /* Find the call we just emitted. */
361 call_insn
= last_call_insn ();
363 /* Mark memory as used for "pure" function call. */
364 if (ecf_flags
& ECF_PURE
)
368 gen_rtx_USE (VOIDmode
,
369 gen_rtx_MEM (BLKmode
, gen_rtx_SCRATCH (VOIDmode
))),
372 /* Put the register usage information there. */
373 add_function_usage_to (call_insn
, call_fusage
);
375 /* If this is a const call, then set the insn's unchanging bit. */
376 if (ecf_flags
& (ECF_CONST
| ECF_PURE
))
377 CONST_OR_PURE_CALL_P (call_insn
) = 1;
379 /* If this call can't throw, attach a REG_EH_REGION reg note to that
381 if (ecf_flags
& ECF_NOTHROW
)
382 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_EH_REGION
, const0_rtx
,
383 REG_NOTES (call_insn
));
386 int rn
= lookup_stmt_eh_region (fntree
);
388 /* If rn < 0, then either (1) tree-ssa not used or (2) doesn't
389 throw, which we already took care of. */
391 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_EH_REGION
, GEN_INT (rn
),
392 REG_NOTES (call_insn
));
393 note_current_region_may_contain_throw ();
396 if (ecf_flags
& ECF_NORETURN
)
397 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_NORETURN
, const0_rtx
,
398 REG_NOTES (call_insn
));
400 if (ecf_flags
& ECF_RETURNS_TWICE
)
402 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_SETJMP
, const0_rtx
,
403 REG_NOTES (call_insn
));
404 current_function_calls_setjmp
= 1;
407 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
409 /* Restore this now, so that we do defer pops for this call's args
410 if the context of the call as a whole permits. */
411 inhibit_defer_pop
= old_inhibit_defer_pop
;
416 CALL_INSN_FUNCTION_USAGE (call_insn
)
417 = gen_rtx_EXPR_LIST (VOIDmode
,
418 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
419 CALL_INSN_FUNCTION_USAGE (call_insn
));
420 rounded_stack_size
-= n_popped
;
421 rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
422 stack_pointer_delta
-= n_popped
;
425 if (!ACCUMULATE_OUTGOING_ARGS
)
427 /* If returning from the subroutine does not automatically pop the args,
428 we need an instruction to pop them sooner or later.
429 Perhaps do it now; perhaps just record how much space to pop later.
431 If returning from the subroutine does pop the args, indicate that the
432 stack pointer will be changed. */
434 if (rounded_stack_size
!= 0)
436 if (ecf_flags
& (ECF_SP_DEPRESSED
| ECF_NORETURN
))
437 /* Just pretend we did the pop. */
438 stack_pointer_delta
-= rounded_stack_size
;
439 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
440 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
441 pending_stack_adjust
+= rounded_stack_size
;
443 adjust_stack (rounded_stack_size_rtx
);
446 /* When we accumulate outgoing args, we must avoid any stack manipulations.
447 Restore the stack pointer to its original value now. Usually
448 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
449 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
450 popping variants of functions exist as well.
452 ??? We may optimize similar to defer_pop above, but it is
453 probably not worthwhile.
455 ??? It will be worthwhile to enable combine_stack_adjustments even for
458 anti_adjust_stack (GEN_INT (n_popped
));
461 /* Determine if the function identified by NAME and FNDECL is one with
462 special properties we wish to know about.
464 For example, if the function might return more than one time (setjmp), then
465 set RETURNS_TWICE to a nonzero value.
467 Similarly set NORETURN if the function is in the longjmp family.
469 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
470 space from the stack such as alloca. */
473 special_function_p (tree fndecl
, int flags
)
475 if (fndecl
&& DECL_NAME (fndecl
)
476 && IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) <= 17
477 /* Exclude functions not at the file scope, or not `extern',
478 since they are not the magic functions we would otherwise
480 FIXME: this should be handled with attributes, not with this
481 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
482 because you can declare fork() inside a function if you
484 && (DECL_CONTEXT (fndecl
) == NULL_TREE
485 || TREE_CODE (DECL_CONTEXT (fndecl
)) == TRANSLATION_UNIT_DECL
)
486 && TREE_PUBLIC (fndecl
))
488 const char *name
= IDENTIFIER_POINTER (DECL_NAME (fndecl
));
489 const char *tname
= name
;
491 /* We assume that alloca will always be called by name. It
492 makes no sense to pass it as a pointer-to-function to
493 anything that does not understand its behavior. */
494 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 6
496 && ! strcmp (name
, "alloca"))
497 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 16
499 && ! strcmp (name
, "__builtin_alloca"))))
500 flags
|= ECF_MAY_BE_ALLOCA
;
502 /* Disregard prefix _, __ or __x. */
505 if (name
[1] == '_' && name
[2] == 'x')
507 else if (name
[1] == '_')
516 && (! strcmp (tname
, "setjmp")
517 || ! strcmp (tname
, "setjmp_syscall")))
519 && ! strcmp (tname
, "sigsetjmp"))
521 && ! strcmp (tname
, "savectx")))
522 flags
|= ECF_RETURNS_TWICE
;
525 && ! strcmp (tname
, "siglongjmp"))
526 flags
|= ECF_NORETURN
;
528 else if ((tname
[0] == 'q' && tname
[1] == 's'
529 && ! strcmp (tname
, "qsetjmp"))
530 || (tname
[0] == 'v' && tname
[1] == 'f'
531 && ! strcmp (tname
, "vfork"))
532 || (tname
[0] == 'g' && tname
[1] == 'e'
533 && !strcmp (tname
, "getcontext")))
534 flags
|= ECF_RETURNS_TWICE
;
536 else if (tname
[0] == 'l' && tname
[1] == 'o'
537 && ! strcmp (tname
, "longjmp"))
538 flags
|= ECF_NORETURN
;
544 /* Return nonzero when FNDECL represents a call to setjmp. */
547 setjmp_call_p (tree fndecl
)
549 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
552 /* Return true when exp contains alloca call. */
554 alloca_call_p (tree exp
)
556 if (TREE_CODE (exp
) == CALL_EXPR
557 && TREE_CODE (CALL_EXPR_FN (exp
)) == ADDR_EXPR
558 && (TREE_CODE (TREE_OPERAND (CALL_EXPR_FN (exp
), 0)) == FUNCTION_DECL
)
559 && (special_function_p (TREE_OPERAND (CALL_EXPR_FN (exp
), 0), 0)
560 & ECF_MAY_BE_ALLOCA
))
565 /* Detect flags (function attributes) from the function decl or type node. */
568 flags_from_decl_or_type (tree exp
)
575 type
= TREE_TYPE (exp
);
577 /* The function exp may have the `malloc' attribute. */
578 if (DECL_IS_MALLOC (exp
))
581 /* The function exp may have the `returns_twice' attribute. */
582 if (DECL_IS_RETURNS_TWICE (exp
))
583 flags
|= ECF_RETURNS_TWICE
;
585 /* The function exp may have the `pure' attribute. */
586 if (DECL_IS_PURE (exp
))
589 if (DECL_IS_NOVOPS (exp
))
592 if (TREE_NOTHROW (exp
))
593 flags
|= ECF_NOTHROW
;
595 if (TREE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
598 flags
= special_function_p (exp
, flags
);
600 else if (TYPE_P (exp
) && TYPE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
603 if (TREE_THIS_VOLATILE (exp
))
604 flags
|= ECF_NORETURN
;
606 /* Mark if the function returns with the stack pointer depressed. We
607 cannot consider it pure or constant in that case. */
608 if (TREE_CODE (type
) == FUNCTION_TYPE
&& TYPE_RETURNS_STACK_DEPRESSED (type
))
610 flags
|= ECF_SP_DEPRESSED
;
611 flags
&= ~(ECF_PURE
| ECF_CONST
);
617 /* Detect flags from a CALL_EXPR. */
620 call_expr_flags (tree t
)
623 tree decl
= get_callee_fndecl (t
);
626 flags
= flags_from_decl_or_type (decl
);
629 t
= TREE_TYPE (CALL_EXPR_FN (t
));
630 if (t
&& TREE_CODE (t
) == POINTER_TYPE
)
631 flags
= flags_from_decl_or_type (TREE_TYPE (t
));
639 /* Precompute all register parameters as described by ARGS, storing values
640 into fields within the ARGS array.
642 NUM_ACTUALS indicates the total number elements in the ARGS array.
644 Set REG_PARM_SEEN if we encounter a register parameter. */
647 precompute_register_parameters (int num_actuals
, struct arg_data
*args
,
654 for (i
= 0; i
< num_actuals
; i
++)
655 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
659 if (args
[i
].value
== 0)
662 args
[i
].value
= expand_normal (args
[i
].tree_value
);
663 preserve_temp_slots (args
[i
].value
);
667 /* If the value is a non-legitimate constant, force it into a
668 pseudo now. TLS symbols sometimes need a call to resolve. */
669 if (CONSTANT_P (args
[i
].value
)
670 && !LEGITIMATE_CONSTANT_P (args
[i
].value
))
671 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
673 /* If we are to promote the function arg to a wider mode,
676 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
678 = convert_modes (args
[i
].mode
,
679 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
680 args
[i
].value
, args
[i
].unsignedp
);
682 /* If we're going to have to load the value by parts, pull the
683 parts into pseudos. The part extraction process can involve
684 non-trivial computation. */
685 if (GET_CODE (args
[i
].reg
) == PARALLEL
)
687 tree type
= TREE_TYPE (args
[i
].tree_value
);
688 args
[i
].parallel_value
689 = emit_group_load_into_temps (args
[i
].reg
, args
[i
].value
,
690 type
, int_size_in_bytes (type
));
693 /* If the value is expensive, and we are inside an appropriately
694 short loop, put the value into a pseudo and then put the pseudo
697 For small register classes, also do this if this call uses
698 register parameters. This is to avoid reload conflicts while
699 loading the parameters registers. */
701 else if ((! (REG_P (args
[i
].value
)
702 || (GET_CODE (args
[i
].value
) == SUBREG
703 && REG_P (SUBREG_REG (args
[i
].value
)))))
704 && args
[i
].mode
!= BLKmode
705 && rtx_cost (args
[i
].value
, SET
) > COSTS_N_INSNS (1)
706 && ((SMALL_REGISTER_CLASSES
&& *reg_parm_seen
)
708 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
712 #ifdef REG_PARM_STACK_SPACE
714 /* The argument list is the property of the called routine and it
715 may clobber it. If the fixed area has been used for previous
716 parameters, we must save and restore it. */
719 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
724 /* Compute the boundary of the area that needs to be saved, if any. */
725 high
= reg_parm_stack_space
;
726 #ifdef ARGS_GROW_DOWNWARD
729 if (high
> highest_outgoing_arg_in_use
)
730 high
= highest_outgoing_arg_in_use
;
732 for (low
= 0; low
< high
; low
++)
733 if (stack_usage_map
[low
] != 0)
736 enum machine_mode save_mode
;
741 while (stack_usage_map
[--high
] == 0)
745 *high_to_save
= high
;
747 num_to_save
= high
- low
+ 1;
748 save_mode
= mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
750 /* If we don't have the required alignment, must do this
752 if ((low
& (MIN (GET_MODE_SIZE (save_mode
),
753 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
756 #ifdef ARGS_GROW_DOWNWARD
761 stack_area
= gen_rtx_MEM (save_mode
,
762 memory_address (save_mode
,
763 plus_constant (argblock
,
766 set_mem_align (stack_area
, PARM_BOUNDARY
);
767 if (save_mode
== BLKmode
)
769 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
770 emit_block_move (validize_mem (save_area
), stack_area
,
771 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
775 save_area
= gen_reg_rtx (save_mode
);
776 emit_move_insn (save_area
, stack_area
);
786 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
788 enum machine_mode save_mode
= GET_MODE (save_area
);
792 #ifdef ARGS_GROW_DOWNWARD
793 delta
= -high_to_save
;
797 stack_area
= gen_rtx_MEM (save_mode
,
798 memory_address (save_mode
,
799 plus_constant (argblock
, delta
)));
800 set_mem_align (stack_area
, PARM_BOUNDARY
);
802 if (save_mode
!= BLKmode
)
803 emit_move_insn (stack_area
, save_area
);
805 emit_block_move (stack_area
, validize_mem (save_area
),
806 GEN_INT (high_to_save
- low_to_save
+ 1),
809 #endif /* REG_PARM_STACK_SPACE */
811 /* If any elements in ARGS refer to parameters that are to be passed in
812 registers, but not in memory, and whose alignment does not permit a
813 direct copy into registers. Copy the values into a group of pseudos
814 which we will later copy into the appropriate hard registers.
816 Pseudos for each unaligned argument will be stored into the array
817 args[argnum].aligned_regs. The caller is responsible for deallocating
818 the aligned_regs array if it is nonzero. */
821 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
825 for (i
= 0; i
< num_actuals
; i
++)
826 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
827 && args
[i
].mode
== BLKmode
828 && (TYPE_ALIGN (TREE_TYPE (args
[i
].tree_value
))
829 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
831 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
832 int endian_correction
= 0;
836 gcc_assert (args
[i
].partial
% UNITS_PER_WORD
== 0);
837 args
[i
].n_aligned_regs
= args
[i
].partial
/ UNITS_PER_WORD
;
841 args
[i
].n_aligned_regs
842 = (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
845 args
[i
].aligned_regs
= XNEWVEC (rtx
, args
[i
].n_aligned_regs
);
847 /* Structures smaller than a word are normally aligned to the
848 least significant byte. On a BYTES_BIG_ENDIAN machine,
849 this means we must skip the empty high order bytes when
850 calculating the bit offset. */
851 if (bytes
< UNITS_PER_WORD
852 #ifdef BLOCK_REG_PADDING
853 && (BLOCK_REG_PADDING (args
[i
].mode
,
854 TREE_TYPE (args
[i
].tree_value
), 1)
860 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
862 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
864 rtx reg
= gen_reg_rtx (word_mode
);
865 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
866 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
868 args
[i
].aligned_regs
[j
] = reg
;
869 word
= extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
870 word_mode
, word_mode
);
872 /* There is no need to restrict this code to loading items
873 in TYPE_ALIGN sized hunks. The bitfield instructions can
874 load up entire word sized registers efficiently.
876 ??? This may not be needed anymore.
877 We use to emit a clobber here but that doesn't let later
878 passes optimize the instructions we emit. By storing 0 into
879 the register later passes know the first AND to zero out the
880 bitfield being set in the register is unnecessary. The store
881 of 0 will be deleted as will at least the first AND. */
883 emit_move_insn (reg
, const0_rtx
);
885 bytes
-= bitsize
/ BITS_PER_UNIT
;
886 store_bit_field (reg
, bitsize
, endian_correction
, word_mode
,
892 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
895 NUM_ACTUALS is the total number of parameters.
897 N_NAMED_ARGS is the total number of named arguments.
899 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
902 FNDECL is the tree code for the target of this call (if known)
904 ARGS_SO_FAR holds state needed by the target to know where to place
907 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
908 for arguments which are passed in registers.
910 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
911 and may be modified by this routine.
913 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
914 flags which may may be modified by this routine.
916 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
917 that requires allocation of stack space.
919 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
920 the thunked-to function. */
923 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
924 struct arg_data
*args
,
925 struct args_size
*args_size
,
926 int n_named_args ATTRIBUTE_UNUSED
,
927 tree exp
, tree struct_value_addr_value
,
929 CUMULATIVE_ARGS
*args_so_far
,
930 int reg_parm_stack_space
,
931 rtx
*old_stack_level
, int *old_pending_adj
,
932 int *must_preallocate
, int *ecf_flags
,
933 bool *may_tailcall
, bool call_from_thunk_p
)
935 /* 1 if scanning parms front to back, -1 if scanning back to front. */
938 /* Count arg position in order args appear. */
943 args_size
->constant
= 0;
946 /* In this loop, we consider args in the order they are written.
947 We fill up ARGS from the front or from the back if necessary
948 so that in any case the first arg to be pushed ends up at the front. */
950 if (PUSH_ARGS_REVERSED
)
952 i
= num_actuals
- 1, inc
= -1;
953 /* In this case, must reverse order of args
954 so that we compute and push the last arg first. */
961 /* First fill in the actual arguments in the ARGS array, splitting
962 complex arguments if necessary. */
965 call_expr_arg_iterator iter
;
968 if (struct_value_addr_value
)
970 args
[j
].tree_value
= struct_value_addr_value
;
973 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
975 tree argtype
= TREE_TYPE (arg
);
976 if (targetm
.calls
.split_complex_arg
978 && TREE_CODE (argtype
) == COMPLEX_TYPE
979 && targetm
.calls
.split_complex_arg (argtype
))
981 tree subtype
= TREE_TYPE (argtype
);
982 arg
= save_expr (arg
);
983 args
[j
].tree_value
= build1 (REALPART_EXPR
, subtype
, arg
);
985 args
[j
].tree_value
= build1 (IMAGPART_EXPR
, subtype
, arg
);
988 args
[j
].tree_value
= arg
;
993 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
994 for (argpos
= 0; argpos
< num_actuals
; i
+= inc
, argpos
++)
996 tree type
= TREE_TYPE (args
[i
].tree_value
);
998 enum machine_mode mode
;
1000 /* Replace erroneous argument with constant zero. */
1001 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1002 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1004 /* If TYPE is a transparent union, pass things the way we would
1005 pass the first field of the union. We have already verified that
1006 the modes are the same. */
1007 if (TREE_CODE (type
) == UNION_TYPE
&& TYPE_TRANSPARENT_UNION (type
))
1008 type
= TREE_TYPE (TYPE_FIELDS (type
));
1010 /* Decide where to pass this arg.
1012 args[i].reg is nonzero if all or part is passed in registers.
1014 args[i].partial is nonzero if part but not all is passed in registers,
1015 and the exact value says how many bytes are passed in registers.
1017 args[i].pass_on_stack is nonzero if the argument must at least be
1018 computed on the stack. It may then be loaded back into registers
1019 if args[i].reg is nonzero.
1021 These decisions are driven by the FUNCTION_... macros and must agree
1022 with those made by function.c. */
1024 /* See if this argument should be passed by invisible reference. */
1025 if (pass_by_reference (args_so_far
, TYPE_MODE (type
),
1026 type
, argpos
< n_named_args
))
1032 = reference_callee_copied (args_so_far
, TYPE_MODE (type
),
1033 type
, argpos
< n_named_args
);
1035 /* If we're compiling a thunk, pass through invisible references
1036 instead of making a copy. */
1037 if (call_from_thunk_p
1039 && !TREE_ADDRESSABLE (type
)
1040 && (base
= get_base_address (args
[i
].tree_value
))
1041 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
)))))
1043 /* We can't use sibcalls if a callee-copied argument is
1044 stored in the current function's frame. */
1045 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
1046 *may_tailcall
= false;
1048 args
[i
].tree_value
= build_fold_addr_expr (args
[i
].tree_value
);
1049 type
= TREE_TYPE (args
[i
].tree_value
);
1051 *ecf_flags
&= ~(ECF_CONST
| ECF_LIBCALL_BLOCK
);
1055 /* We make a copy of the object and pass the address to the
1056 function being called. */
1059 if (!COMPLETE_TYPE_P (type
)
1060 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1061 || (flag_stack_check
&& ! STACK_CHECK_BUILTIN
1062 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type
),
1063 STACK_CHECK_MAX_VAR_SIZE
))))
1065 /* This is a variable-sized object. Make space on the stack
1067 rtx size_rtx
= expr_size (args
[i
].tree_value
);
1069 if (*old_stack_level
== 0)
1071 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1072 *old_pending_adj
= pending_stack_adjust
;
1073 pending_stack_adjust
= 0;
1076 copy
= gen_rtx_MEM (BLKmode
,
1077 allocate_dynamic_stack_space
1078 (size_rtx
, NULL_RTX
, TYPE_ALIGN (type
)));
1079 set_mem_attributes (copy
, type
, 1);
1082 copy
= assign_temp (type
, 0, 1, 0);
1084 store_expr (args
[i
].tree_value
, copy
, 0, false);
1087 *ecf_flags
&= ~(ECF_CONST
| ECF_LIBCALL_BLOCK
);
1089 *ecf_flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
1092 = build_fold_addr_expr (make_tree (type
, copy
));
1093 type
= TREE_TYPE (args
[i
].tree_value
);
1094 *may_tailcall
= false;
1098 mode
= TYPE_MODE (type
);
1099 unsignedp
= TYPE_UNSIGNED (type
);
1101 if (targetm
.calls
.promote_function_args (fndecl
? TREE_TYPE (fndecl
) : 0))
1102 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
1104 args
[i
].unsignedp
= unsignedp
;
1105 args
[i
].mode
= mode
;
1107 args
[i
].reg
= FUNCTION_ARG (*args_so_far
, mode
, type
,
1108 argpos
< n_named_args
);
1109 #ifdef FUNCTION_INCOMING_ARG
1110 /* If this is a sibling call and the machine has register windows, the
1111 register window has to be unwinded before calling the routine, so
1112 arguments have to go into the incoming registers. */
1113 args
[i
].tail_call_reg
= FUNCTION_INCOMING_ARG (*args_so_far
, mode
, type
,
1114 argpos
< n_named_args
);
1116 args
[i
].tail_call_reg
= args
[i
].reg
;
1121 = targetm
.calls
.arg_partial_bytes (args_so_far
, mode
, type
,
1122 argpos
< n_named_args
);
1124 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (mode
, type
);
1126 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1127 it means that we are to pass this arg in the register(s) designated
1128 by the PARALLEL, but also to pass it in the stack. */
1129 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1130 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1131 args
[i
].pass_on_stack
= 1;
1133 /* If this is an addressable type, we must preallocate the stack
1134 since we must evaluate the object into its final location.
1136 If this is to be passed in both registers and the stack, it is simpler
1138 if (TREE_ADDRESSABLE (type
)
1139 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1140 *must_preallocate
= 1;
1142 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1143 we cannot consider this function call constant. */
1144 if (TREE_ADDRESSABLE (type
))
1145 *ecf_flags
&= ~ECF_LIBCALL_BLOCK
;
1147 /* Compute the stack-size of this argument. */
1148 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1149 || reg_parm_stack_space
> 0
1150 || args
[i
].pass_on_stack
)
1151 locate_and_pad_parm (mode
, type
,
1152 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1157 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
1158 fndecl
, args_size
, &args
[i
].locate
);
1159 #ifdef BLOCK_REG_PADDING
1161 /* The argument is passed entirely in registers. See at which
1162 end it should be padded. */
1163 args
[i
].locate
.where_pad
=
1164 BLOCK_REG_PADDING (mode
, type
,
1165 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
1168 /* Update ARGS_SIZE, the total stack space for args so far. */
1170 args_size
->constant
+= args
[i
].locate
.size
.constant
;
1171 if (args
[i
].locate
.size
.var
)
1172 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
1174 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1175 have been used, etc. */
1177 FUNCTION_ARG_ADVANCE (*args_so_far
, TYPE_MODE (type
), type
,
1178 argpos
< n_named_args
);
1182 /* Update ARGS_SIZE to contain the total size for the argument block.
1183 Return the original constant component of the argument block's size.
1185 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1186 for arguments passed in registers. */
1189 compute_argument_block_size (int reg_parm_stack_space
,
1190 struct args_size
*args_size
,
1191 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
1193 int unadjusted_args_size
= args_size
->constant
;
1195 /* For accumulate outgoing args mode we don't need to align, since the frame
1196 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1197 backends from generating misaligned frame sizes. */
1198 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1199 preferred_stack_boundary
= STACK_BOUNDARY
;
1201 /* Compute the actual size of the argument block required. The variable
1202 and constant sizes must be combined, the size may have to be rounded,
1203 and there may be a minimum required size. */
1207 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1208 args_size
->constant
= 0;
1210 preferred_stack_boundary
/= BITS_PER_UNIT
;
1211 if (preferred_stack_boundary
> 1)
1213 /* We don't handle this case yet. To handle it correctly we have
1214 to add the delta, round and subtract the delta.
1215 Currently no machine description requires this support. */
1216 gcc_assert (!(stack_pointer_delta
& (preferred_stack_boundary
- 1)));
1217 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1220 if (reg_parm_stack_space
> 0)
1223 = size_binop (MAX_EXPR
, args_size
->var
,
1224 ssize_int (reg_parm_stack_space
));
1226 /* The area corresponding to register parameters is not to count in
1227 the size of the block we need. So make the adjustment. */
1228 if (!OUTGOING_REG_PARM_STACK_SPACE
)
1230 = size_binop (MINUS_EXPR
, args_size
->var
,
1231 ssize_int (reg_parm_stack_space
));
1236 preferred_stack_boundary
/= BITS_PER_UNIT
;
1237 if (preferred_stack_boundary
< 1)
1238 preferred_stack_boundary
= 1;
1239 args_size
->constant
= (((args_size
->constant
1240 + stack_pointer_delta
1241 + preferred_stack_boundary
- 1)
1242 / preferred_stack_boundary
1243 * preferred_stack_boundary
)
1244 - stack_pointer_delta
);
1246 args_size
->constant
= MAX (args_size
->constant
,
1247 reg_parm_stack_space
);
1249 if (!OUTGOING_REG_PARM_STACK_SPACE
)
1250 args_size
->constant
-= reg_parm_stack_space
;
1252 return unadjusted_args_size
;
1255 /* Precompute parameters as needed for a function call.
1257 FLAGS is mask of ECF_* constants.
1259 NUM_ACTUALS is the number of arguments.
1261 ARGS is an array containing information for each argument; this
1262 routine fills in the INITIAL_VALUE and VALUE fields for each
1263 precomputed argument. */
1266 precompute_arguments (int flags
, int num_actuals
, struct arg_data
*args
)
1270 /* If this is a libcall, then precompute all arguments so that we do not
1271 get extraneous instructions emitted as part of the libcall sequence. */
1273 /* If we preallocated the stack space, and some arguments must be passed
1274 on the stack, then we must precompute any parameter which contains a
1275 function call which will store arguments on the stack.
1276 Otherwise, evaluating the parameter may clobber previous parameters
1277 which have already been stored into the stack. (we have code to avoid
1278 such case by saving the outgoing stack arguments, but it results in
1280 if ((flags
& ECF_LIBCALL_BLOCK
) == 0 && !ACCUMULATE_OUTGOING_ARGS
)
1283 for (i
= 0; i
< num_actuals
; i
++)
1285 enum machine_mode mode
;
1287 if ((flags
& ECF_LIBCALL_BLOCK
) == 0
1288 && TREE_CODE (args
[i
].tree_value
) != CALL_EXPR
)
1291 /* If this is an addressable type, we cannot pre-evaluate it. */
1292 gcc_assert (!TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
)));
1294 args
[i
].initial_value
= args
[i
].value
1295 = expand_normal (args
[i
].tree_value
);
1297 mode
= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
));
1298 if (mode
!= args
[i
].mode
)
1301 = convert_modes (args
[i
].mode
, mode
,
1302 args
[i
].value
, args
[i
].unsignedp
);
1303 #if defined(PROMOTE_FUNCTION_MODE) && !defined(PROMOTE_MODE)
1304 /* CSE will replace this only if it contains args[i].value
1305 pseudo, so convert it down to the declared mode using
1307 if (REG_P (args
[i
].value
)
1308 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
)
1310 args
[i
].initial_value
1311 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1312 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1313 SUBREG_PROMOTED_UNSIGNED_SET (args
[i
].initial_value
,
1321 /* Given the current state of MUST_PREALLOCATE and information about
1322 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1323 compute and return the final value for MUST_PREALLOCATE. */
1326 finalize_must_preallocate (int must_preallocate
, int num_actuals
,
1327 struct arg_data
*args
, struct args_size
*args_size
)
1329 /* See if we have or want to preallocate stack space.
1331 If we would have to push a partially-in-regs parm
1332 before other stack parms, preallocate stack space instead.
1334 If the size of some parm is not a multiple of the required stack
1335 alignment, we must preallocate.
1337 If the total size of arguments that would otherwise create a copy in
1338 a temporary (such as a CALL) is more than half the total argument list
1339 size, preallocation is faster.
1341 Another reason to preallocate is if we have a machine (like the m88k)
1342 where stack alignment is required to be maintained between every
1343 pair of insns, not just when the call is made. However, we assume here
1344 that such machines either do not have push insns (and hence preallocation
1345 would occur anyway) or the problem is taken care of with
1348 if (! must_preallocate
)
1350 int partial_seen
= 0;
1351 int copy_to_evaluate_size
= 0;
1354 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1356 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1358 else if (partial_seen
&& args
[i
].reg
== 0)
1359 must_preallocate
= 1;
1361 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1362 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1363 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1364 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1365 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1366 copy_to_evaluate_size
1367 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1370 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1371 && args_size
->constant
> 0)
1372 must_preallocate
= 1;
1374 return must_preallocate
;
1377 /* If we preallocated stack space, compute the address of each argument
1378 and store it into the ARGS array.
1380 We need not ensure it is a valid memory address here; it will be
1381 validized when it is used.
1383 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1386 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
1390 rtx arg_reg
= argblock
;
1391 int i
, arg_offset
= 0;
1393 if (GET_CODE (argblock
) == PLUS
)
1394 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1396 for (i
= 0; i
< num_actuals
; i
++)
1398 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
1399 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
1401 unsigned int align
, boundary
;
1402 unsigned int units_on_stack
= 0;
1403 enum machine_mode partial_mode
= VOIDmode
;
1405 /* Skip this parm if it will not be passed on the stack. */
1406 if (! args
[i
].pass_on_stack
1408 && args
[i
].partial
== 0)
1411 if (GET_CODE (offset
) == CONST_INT
)
1412 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1414 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1416 addr
= plus_constant (addr
, arg_offset
);
1418 if (args
[i
].partial
!= 0)
1420 /* Only part of the parameter is being passed on the stack.
1421 Generate a simple memory reference of the correct size. */
1422 units_on_stack
= args
[i
].locate
.size
.constant
;
1423 partial_mode
= mode_for_size (units_on_stack
* BITS_PER_UNIT
,
1425 args
[i
].stack
= gen_rtx_MEM (partial_mode
, addr
);
1426 set_mem_size (args
[i
].stack
, GEN_INT (units_on_stack
));
1430 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1431 set_mem_attributes (args
[i
].stack
,
1432 TREE_TYPE (args
[i
].tree_value
), 1);
1434 align
= BITS_PER_UNIT
;
1435 boundary
= args
[i
].locate
.boundary
;
1436 if (args
[i
].locate
.where_pad
!= downward
)
1438 else if (GET_CODE (offset
) == CONST_INT
)
1440 align
= INTVAL (offset
) * BITS_PER_UNIT
| boundary
;
1441 align
= align
& -align
;
1443 set_mem_align (args
[i
].stack
, align
);
1445 if (GET_CODE (slot_offset
) == CONST_INT
)
1446 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1448 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_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.
1457 args
[i
].stack_slot
= gen_rtx_MEM (partial_mode
, addr
);
1458 set_mem_size (args
[i
].stack_slot
, GEN_INT (units_on_stack
));
1462 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1463 set_mem_attributes (args
[i
].stack_slot
,
1464 TREE_TYPE (args
[i
].tree_value
), 1);
1466 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
1468 /* Function incoming arguments may overlap with sibling call
1469 outgoing arguments and we cannot allow reordering of reads
1470 from function arguments with stores to outgoing arguments
1471 of sibling calls. */
1472 set_mem_alias_set (args
[i
].stack
, 0);
1473 set_mem_alias_set (args
[i
].stack_slot
, 0);
1478 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1479 in a call instruction.
1481 FNDECL is the tree node for the target function. For an indirect call
1482 FNDECL will be NULL_TREE.
1484 ADDR is the operand 0 of CALL_EXPR for this call. */
1487 rtx_for_function_call (tree fndecl
, tree addr
)
1491 /* Get the function to call, in the form of RTL. */
1494 /* If this is the first use of the function, see if we need to
1495 make an external definition for it. */
1496 if (! TREE_USED (fndecl
))
1498 assemble_external (fndecl
);
1499 TREE_USED (fndecl
) = 1;
1502 /* Get a SYMBOL_REF rtx for the function address. */
1503 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1506 /* Generate an rtx (probably a pseudo-register) for the address. */
1509 funexp
= expand_normal (addr
);
1510 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1515 /* Return true if and only if SIZE storage units (usually bytes)
1516 starting from address ADDR overlap with already clobbered argument
1517 area. This function is used to determine if we should give up a
1521 mem_overlaps_already_clobbered_arg_p (rtx addr
, unsigned HOST_WIDE_INT size
)
1525 if (addr
== current_function_internal_arg_pointer
)
1527 else if (GET_CODE (addr
) == PLUS
1528 && XEXP (addr
, 0) == current_function_internal_arg_pointer
1529 && GET_CODE (XEXP (addr
, 1)) == CONST_INT
)
1530 i
= INTVAL (XEXP (addr
, 1));
1531 /* Return true for arg pointer based indexed addressing. */
1532 else if (GET_CODE (addr
) == PLUS
1533 && (XEXP (addr
, 0) == current_function_internal_arg_pointer
1534 || XEXP (addr
, 1) == current_function_internal_arg_pointer
))
1539 #ifdef ARGS_GROW_DOWNWARD
1544 unsigned HOST_WIDE_INT k
;
1546 for (k
= 0; k
< size
; k
++)
1547 if (i
+ k
< stored_args_map
->n_bits
1548 && TEST_BIT (stored_args_map
, i
+ k
))
1555 /* Do the register loads required for any wholly-register parms or any
1556 parms which are passed both on the stack and in a register. Their
1557 expressions were already evaluated.
1559 Mark all register-parms as living through the call, putting these USE
1560 insns in the CALL_INSN_FUNCTION_USAGE field.
1562 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1563 checking, setting *SIBCALL_FAILURE if appropriate. */
1566 load_register_parameters (struct arg_data
*args
, int num_actuals
,
1567 rtx
*call_fusage
, int flags
, int is_sibcall
,
1568 int *sibcall_failure
)
1572 for (i
= 0; i
< num_actuals
; i
++)
1574 rtx reg
= ((flags
& ECF_SIBCALL
)
1575 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1578 int partial
= args
[i
].partial
;
1581 rtx before_arg
= get_last_insn ();
1582 /* Set non-negative if we must move a word at a time, even if
1583 just one word (e.g, partial == 4 && mode == DFmode). Set
1584 to -1 if we just use a normal move insn. This value can be
1585 zero if the argument is a zero size structure. */
1587 if (GET_CODE (reg
) == PARALLEL
)
1591 gcc_assert (partial
% UNITS_PER_WORD
== 0);
1592 nregs
= partial
/ UNITS_PER_WORD
;
1594 else if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
)
1596 size
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1597 nregs
= (size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1600 size
= GET_MODE_SIZE (args
[i
].mode
);
1602 /* Handle calls that pass values in multiple non-contiguous
1603 locations. The Irix 6 ABI has examples of this. */
1605 if (GET_CODE (reg
) == PARALLEL
)
1606 emit_group_move (reg
, args
[i
].parallel_value
);
1608 /* If simple case, just do move. If normal partial, store_one_arg
1609 has already loaded the register for us. In all other cases,
1610 load the register(s) from memory. */
1612 else if (nregs
== -1)
1614 emit_move_insn (reg
, args
[i
].value
);
1615 #ifdef BLOCK_REG_PADDING
1616 /* Handle case where we have a value that needs shifting
1617 up to the msb. eg. a QImode value and we're padding
1618 upward on a BYTES_BIG_ENDIAN machine. */
1619 if (size
< UNITS_PER_WORD
1620 && (args
[i
].locate
.where_pad
1621 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
1624 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1626 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1627 report the whole reg as used. Strictly speaking, the
1628 call only uses SIZE bytes at the msb end, but it doesn't
1629 seem worth generating rtl to say that. */
1630 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
1631 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
1632 build_int_cst (NULL_TREE
, shift
),
1635 emit_move_insn (reg
, x
);
1640 /* If we have pre-computed the values to put in the registers in
1641 the case of non-aligned structures, copy them in now. */
1643 else if (args
[i
].n_aligned_regs
!= 0)
1644 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1645 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1646 args
[i
].aligned_regs
[j
]);
1648 else if (partial
== 0 || args
[i
].pass_on_stack
)
1650 rtx mem
= validize_mem (args
[i
].value
);
1652 /* Check for overlap with already clobbered argument area. */
1654 && mem_overlaps_already_clobbered_arg_p (XEXP (args
[i
].value
, 0),
1656 *sibcall_failure
= 1;
1658 /* Handle a BLKmode that needs shifting. */
1659 if (nregs
== 1 && size
< UNITS_PER_WORD
1660 #ifdef BLOCK_REG_PADDING
1661 && args
[i
].locate
.where_pad
== downward
1667 rtx tem
= operand_subword_force (mem
, 0, args
[i
].mode
);
1668 rtx ri
= gen_rtx_REG (word_mode
, REGNO (reg
));
1669 rtx x
= gen_reg_rtx (word_mode
);
1670 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1671 enum tree_code dir
= BYTES_BIG_ENDIAN
? RSHIFT_EXPR
1674 emit_move_insn (x
, tem
);
1675 x
= expand_shift (dir
, word_mode
, x
,
1676 build_int_cst (NULL_TREE
, shift
),
1679 emit_move_insn (ri
, x
);
1682 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
1685 /* When a parameter is a block, and perhaps in other cases, it is
1686 possible that it did a load from an argument slot that was
1687 already clobbered. */
1689 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
1690 *sibcall_failure
= 1;
1692 /* Handle calls that pass values in multiple non-contiguous
1693 locations. The Irix 6 ABI has examples of this. */
1694 if (GET_CODE (reg
) == PARALLEL
)
1695 use_group_regs (call_fusage
, reg
);
1696 else if (nregs
== -1)
1697 use_reg (call_fusage
, reg
);
1699 use_regs (call_fusage
, REGNO (reg
), nregs
);
1704 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1705 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1706 bytes, then we would need to push some additional bytes to pad the
1707 arguments. So, we compute an adjust to the stack pointer for an
1708 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1709 bytes. Then, when the arguments are pushed the stack will be perfectly
1710 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1711 be popped after the call. Returns the adjustment. */
1714 combine_pending_stack_adjustment_and_call (int unadjusted_args_size
,
1715 struct args_size
*args_size
,
1716 unsigned int preferred_unit_stack_boundary
)
1718 /* The number of bytes to pop so that the stack will be
1719 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1720 HOST_WIDE_INT adjustment
;
1721 /* The alignment of the stack after the arguments are pushed, if we
1722 just pushed the arguments without adjust the stack here. */
1723 unsigned HOST_WIDE_INT unadjusted_alignment
;
1725 unadjusted_alignment
1726 = ((stack_pointer_delta
+ unadjusted_args_size
)
1727 % preferred_unit_stack_boundary
);
1729 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1730 as possible -- leaving just enough left to cancel out the
1731 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1732 PENDING_STACK_ADJUST is non-negative, and congruent to
1733 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1735 /* Begin by trying to pop all the bytes. */
1736 unadjusted_alignment
1737 = (unadjusted_alignment
1738 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1739 adjustment
= pending_stack_adjust
;
1740 /* Push enough additional bytes that the stack will be aligned
1741 after the arguments are pushed. */
1742 if (preferred_unit_stack_boundary
> 1)
1744 if (unadjusted_alignment
> 0)
1745 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1747 adjustment
+= unadjusted_alignment
;
1750 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1751 bytes after the call. The right number is the entire
1752 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1753 by the arguments in the first place. */
1755 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1760 /* Scan X expression if it does not dereference any argument slots
1761 we already clobbered by tail call arguments (as noted in stored_args_map
1763 Return nonzero if X expression dereferences such argument slots,
1767 check_sibcall_argument_overlap_1 (rtx x
)
1776 code
= GET_CODE (x
);
1779 return mem_overlaps_already_clobbered_arg_p (XEXP (x
, 0),
1780 GET_MODE_SIZE (GET_MODE (x
)));
1782 /* Scan all subexpressions. */
1783 fmt
= GET_RTX_FORMAT (code
);
1784 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
1788 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
1791 else if (*fmt
== 'E')
1793 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
1794 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
1801 /* Scan sequence after INSN if it does not dereference any argument slots
1802 we already clobbered by tail call arguments (as noted in stored_args_map
1803 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1804 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1805 should be 0). Return nonzero if sequence after INSN dereferences such argument
1806 slots, zero otherwise. */
1809 check_sibcall_argument_overlap (rtx insn
, struct arg_data
*arg
, int mark_stored_args_map
)
1813 if (insn
== NULL_RTX
)
1814 insn
= get_insns ();
1816 insn
= NEXT_INSN (insn
);
1818 for (; insn
; insn
= NEXT_INSN (insn
))
1820 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
1823 if (mark_stored_args_map
)
1825 #ifdef ARGS_GROW_DOWNWARD
1826 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
1828 low
= arg
->locate
.slot_offset
.constant
;
1831 for (high
= low
+ arg
->locate
.size
.constant
; low
< high
; low
++)
1832 SET_BIT (stored_args_map
, low
);
1834 return insn
!= NULL_RTX
;
1837 /* Given that a function returns a value of mode MODE at the most
1838 significant end of hard register VALUE, shift VALUE left or right
1839 as specified by LEFT_P. Return true if some action was needed. */
1842 shift_return_value (enum machine_mode mode
, bool left_p
, rtx value
)
1844 HOST_WIDE_INT shift
;
1846 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
1847 shift
= GET_MODE_BITSIZE (GET_MODE (value
)) - GET_MODE_BITSIZE (mode
);
1851 /* Use ashr rather than lshr for right shifts. This is for the benefit
1852 of the MIPS port, which requires SImode values to be sign-extended
1853 when stored in 64-bit registers. */
1854 if (!force_expand_binop (GET_MODE (value
), left_p
? ashl_optab
: ashr_optab
,
1855 value
, GEN_INT (shift
), value
, 1, OPTAB_WIDEN
))
1860 /* Generate all the code for a CALL_EXPR exp
1861 and return an rtx for its value.
1862 Store the value in TARGET (specified as an rtx) if convenient.
1863 If the value is stored in TARGET then TARGET is returned.
1864 If IGNORE is nonzero, then we ignore the value of the function call. */
1867 expand_call (tree exp
, rtx target
, int ignore
)
1869 /* Nonzero if we are currently expanding a call. */
1870 static int currently_expanding_call
= 0;
1872 /* RTX for the function to be called. */
1874 /* Sequence of insns to perform a normal "call". */
1875 rtx normal_call_insns
= NULL_RTX
;
1876 /* Sequence of insns to perform a tail "call". */
1877 rtx tail_call_insns
= NULL_RTX
;
1878 /* Data type of the function. */
1880 tree type_arg_types
;
1881 /* Declaration of the function being called,
1882 or 0 if the function is computed (not known by name). */
1884 /* The type of the function being called. */
1886 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
1889 /* Register in which non-BLKmode value will be returned,
1890 or 0 if no value or if value is BLKmode. */
1892 /* Address where we should return a BLKmode value;
1893 0 if value not BLKmode. */
1894 rtx structure_value_addr
= 0;
1895 /* Nonzero if that address is being passed by treating it as
1896 an extra, implicit first parameter. Otherwise,
1897 it is passed by being copied directly into struct_value_rtx. */
1898 int structure_value_addr_parm
= 0;
1899 /* Holds the value of implicit argument for the struct value. */
1900 tree structure_value_addr_value
= NULL_TREE
;
1901 /* Size of aggregate value wanted, or zero if none wanted
1902 or if we are using the non-reentrant PCC calling convention
1903 or expecting the value in registers. */
1904 HOST_WIDE_INT struct_value_size
= 0;
1905 /* Nonzero if called function returns an aggregate in memory PCC style,
1906 by returning the address of where to find it. */
1907 int pcc_struct_value
= 0;
1908 rtx struct_value
= 0;
1910 /* Number of actual parameters in this call, including struct value addr. */
1912 /* Number of named args. Args after this are anonymous ones
1913 and they must all go on the stack. */
1915 /* Number of complex actual arguments that need to be split. */
1916 int num_complex_actuals
= 0;
1918 /* Vector of information about each argument.
1919 Arguments are numbered in the order they will be pushed,
1920 not the order they are written. */
1921 struct arg_data
*args
;
1923 /* Total size in bytes of all the stack-parms scanned so far. */
1924 struct args_size args_size
;
1925 struct args_size adjusted_args_size
;
1926 /* Size of arguments before any adjustments (such as rounding). */
1927 int unadjusted_args_size
;
1928 /* Data on reg parms scanned so far. */
1929 CUMULATIVE_ARGS args_so_far
;
1930 /* Nonzero if a reg parm has been scanned. */
1932 /* Nonzero if this is an indirect function call. */
1934 /* Nonzero if we must avoid push-insns in the args for this call.
1935 If stack space is allocated for register parameters, but not by the
1936 caller, then it is preallocated in the fixed part of the stack frame.
1937 So the entire argument block must then be preallocated (i.e., we
1938 ignore PUSH_ROUNDING in that case). */
1940 int must_preallocate
= !PUSH_ARGS
;
1942 /* Size of the stack reserved for parameter registers. */
1943 int reg_parm_stack_space
= 0;
1945 /* Address of space preallocated for stack parms
1946 (on machines that lack push insns), or 0 if space not preallocated. */
1949 /* Mask of ECF_ flags. */
1951 #ifdef REG_PARM_STACK_SPACE
1952 /* Define the boundary of the register parm stack space that needs to be
1954 int low_to_save
, high_to_save
;
1955 rtx save_area
= 0; /* Place that it is saved */
1958 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
1959 char *initial_stack_usage_map
= stack_usage_map
;
1960 char *stack_usage_map_buf
= NULL
;
1962 int old_stack_allocated
;
1964 /* State variables to track stack modifications. */
1965 rtx old_stack_level
= 0;
1966 int old_stack_arg_under_construction
= 0;
1967 int old_pending_adj
= 0;
1968 int old_inhibit_defer_pop
= inhibit_defer_pop
;
1970 /* Some stack pointer alterations we make are performed via
1971 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
1972 which we then also need to save/restore along the way. */
1973 int old_stack_pointer_delta
= 0;
1976 tree p
= CALL_EXPR_FN (exp
);
1977 tree addr
= CALL_EXPR_FN (exp
);
1979 /* The alignment of the stack, in bits. */
1980 unsigned HOST_WIDE_INT preferred_stack_boundary
;
1981 /* The alignment of the stack, in bytes. */
1982 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
1983 /* The static chain value to use for this call. */
1984 rtx static_chain_value
;
1985 /* See if this is "nothrow" function call. */
1986 if (TREE_NOTHROW (exp
))
1987 flags
|= ECF_NOTHROW
;
1989 /* See if we can find a DECL-node for the actual function, and get the
1990 function attributes (flags) from the function decl or type node. */
1991 fndecl
= get_callee_fndecl (exp
);
1994 fntype
= TREE_TYPE (fndecl
);
1995 flags
|= flags_from_decl_or_type (fndecl
);
1999 fntype
= TREE_TYPE (TREE_TYPE (p
));
2000 flags
|= flags_from_decl_or_type (fntype
);
2003 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
2005 /* Warn if this value is an aggregate type,
2006 regardless of which calling convention we are using for it. */
2007 if (AGGREGATE_TYPE_P (TREE_TYPE (exp
)))
2008 warning (OPT_Waggregate_return
, "function call has aggregate value");
2010 /* If the result of a pure or const function call is ignored (or void),
2011 and none of its arguments are volatile, we can avoid expanding the
2012 call and just evaluate the arguments for side-effects. */
2013 if ((flags
& (ECF_CONST
| ECF_PURE
))
2014 && (ignore
|| target
== const0_rtx
2015 || TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
))
2017 bool volatilep
= false;
2019 call_expr_arg_iterator iter
;
2021 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2022 if (TREE_THIS_VOLATILE (arg
))
2030 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2031 expand_expr (arg
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
2036 #ifdef REG_PARM_STACK_SPACE
2037 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
2040 if (!OUTGOING_REG_PARM_STACK_SPACE
&& reg_parm_stack_space
> 0 && PUSH_ARGS
)
2041 must_preallocate
= 1;
2043 /* Set up a place to return a structure. */
2045 /* Cater to broken compilers. */
2046 if (aggregate_value_p (exp
, fndecl
))
2048 /* This call returns a big structure. */
2049 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
2051 #ifdef PCC_STATIC_STRUCT_RETURN
2053 pcc_struct_value
= 1;
2055 #else /* not PCC_STATIC_STRUCT_RETURN */
2057 struct_value_size
= int_size_in_bytes (TREE_TYPE (exp
));
2059 if (target
&& MEM_P (target
) && CALL_EXPR_RETURN_SLOT_OPT (exp
))
2060 structure_value_addr
= XEXP (target
, 0);
2063 /* For variable-sized objects, we must be called with a target
2064 specified. If we were to allocate space on the stack here,
2065 we would have no way of knowing when to free it. */
2066 rtx d
= assign_temp (TREE_TYPE (exp
), 0, 1, 1);
2068 mark_temp_addr_taken (d
);
2069 structure_value_addr
= XEXP (d
, 0);
2073 #endif /* not PCC_STATIC_STRUCT_RETURN */
2076 /* Figure out the amount to which the stack should be aligned. */
2077 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2080 struct cgraph_rtl_info
*i
= cgraph_rtl_info (fndecl
);
2081 if (i
&& i
->preferred_incoming_stack_boundary
)
2082 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
2085 /* Operand 0 is a pointer-to-function; get the type of the function. */
2086 funtype
= TREE_TYPE (addr
);
2087 gcc_assert (POINTER_TYPE_P (funtype
));
2088 funtype
= TREE_TYPE (funtype
);
2090 /* Count whether there are actual complex arguments that need to be split
2091 into their real and imaginary parts. Munge the type_arg_types
2092 appropriately here as well. */
2093 if (targetm
.calls
.split_complex_arg
)
2095 call_expr_arg_iterator iter
;
2097 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2099 tree type
= TREE_TYPE (arg
);
2100 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
2101 && targetm
.calls
.split_complex_arg (type
))
2102 num_complex_actuals
++;
2104 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
2107 type_arg_types
= TYPE_ARG_TYPES (funtype
);
2109 if (flags
& ECF_MAY_BE_ALLOCA
)
2110 current_function_calls_alloca
= 1;
2112 /* If struct_value_rtx is 0, it means pass the address
2113 as if it were an extra parameter. Put the argument expression
2114 in structure_value_addr_value. */
2115 if (structure_value_addr
&& struct_value
== 0)
2117 /* If structure_value_addr is a REG other than
2118 virtual_outgoing_args_rtx, we can use always use it. If it
2119 is not a REG, we must always copy it into a register.
2120 If it is virtual_outgoing_args_rtx, we must copy it to another
2121 register in some cases. */
2122 rtx temp
= (!REG_P (structure_value_addr
)
2123 || (ACCUMULATE_OUTGOING_ARGS
2124 && stack_arg_under_construction
2125 && structure_value_addr
== virtual_outgoing_args_rtx
)
2126 ? copy_addr_to_reg (convert_memory_address
2127 (Pmode
, structure_value_addr
))
2128 : structure_value_addr
);
2130 structure_value_addr_value
=
2131 make_tree (build_pointer_type (TREE_TYPE (funtype
)), temp
);
2132 structure_value_addr_parm
= 1;
2135 /* Count the arguments and set NUM_ACTUALS. */
2137 call_expr_nargs (exp
) + num_complex_actuals
+ structure_value_addr_parm
;
2139 /* Compute number of named args.
2140 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2142 if (type_arg_types
!= 0)
2144 = (list_length (type_arg_types
)
2145 /* Count the struct value address, if it is passed as a parm. */
2146 + structure_value_addr_parm
);
2148 /* If we know nothing, treat all args as named. */
2149 n_named_args
= num_actuals
;
2151 /* Start updating where the next arg would go.
2153 On some machines (such as the PA) indirect calls have a different
2154 calling convention than normal calls. The fourth argument in
2155 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2157 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
2159 /* Now possibly adjust the number of named args.
2160 Normally, don't include the last named arg if anonymous args follow.
2161 We do include the last named arg if
2162 targetm.calls.strict_argument_naming() returns nonzero.
2163 (If no anonymous args follow, the result of list_length is actually
2164 one too large. This is harmless.)
2166 If targetm.calls.pretend_outgoing_varargs_named() returns
2167 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2168 this machine will be able to place unnamed args that were passed
2169 in registers into the stack. So treat all args as named. This
2170 allows the insns emitting for a specific argument list to be
2171 independent of the function declaration.
2173 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2174 we do not have any reliable way to pass unnamed args in
2175 registers, so we must force them into memory. */
2177 if (type_arg_types
!= 0
2178 && targetm
.calls
.strict_argument_naming (&args_so_far
))
2180 else if (type_arg_types
!= 0
2181 && ! targetm
.calls
.pretend_outgoing_varargs_named (&args_so_far
))
2182 /* Don't include the last named arg. */
2185 /* Treat all args as named. */
2186 n_named_args
= num_actuals
;
2188 /* Make a vector to hold all the information about each arg. */
2189 args
= alloca (num_actuals
* sizeof (struct arg_data
));
2190 memset (args
, 0, num_actuals
* sizeof (struct arg_data
));
2192 /* Build up entries in the ARGS array, compute the size of the
2193 arguments into ARGS_SIZE, etc. */
2194 initialize_argument_information (num_actuals
, args
, &args_size
,
2196 structure_value_addr_value
, fndecl
,
2197 &args_so_far
, reg_parm_stack_space
,
2198 &old_stack_level
, &old_pending_adj
,
2199 &must_preallocate
, &flags
,
2200 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
2204 /* If this function requires a variable-sized argument list, don't
2205 try to make a cse'able block for this call. We may be able to
2206 do this eventually, but it is too complicated to keep track of
2207 what insns go in the cse'able block and which don't. */
2209 flags
&= ~ECF_LIBCALL_BLOCK
;
2210 must_preallocate
= 1;
2213 /* Now make final decision about preallocating stack space. */
2214 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2218 /* If the structure value address will reference the stack pointer, we
2219 must stabilize it. We don't need to do this if we know that we are
2220 not going to adjust the stack pointer in processing this call. */
2222 if (structure_value_addr
2223 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2224 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2225 structure_value_addr
))
2227 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2228 structure_value_addr
= copy_to_reg (structure_value_addr
);
2230 /* Tail calls can make things harder to debug, and we've traditionally
2231 pushed these optimizations into -O2. Don't try if we're already
2232 expanding a call, as that means we're an argument. Don't try if
2233 there's cleanups, as we know there's code to follow the call. */
2235 if (currently_expanding_call
++ != 0
2236 || !flag_optimize_sibling_calls
2238 || lookup_stmt_eh_region (exp
) >= 0
2239 || dbg_cnt (tail_call
) == false)
2242 /* Rest of purposes for tail call optimizations to fail. */
2244 #ifdef HAVE_sibcall_epilogue
2245 !HAVE_sibcall_epilogue
2250 /* Doing sibling call optimization needs some work, since
2251 structure_value_addr can be allocated on the stack.
2252 It does not seem worth the effort since few optimizable
2253 sibling calls will return a structure. */
2254 || structure_value_addr
!= NULL_RTX
2255 /* Check whether the target is able to optimize the call
2257 || !targetm
.function_ok_for_sibcall (fndecl
, exp
)
2258 /* Functions that do not return exactly once may not be sibcall
2260 || (flags
& (ECF_RETURNS_TWICE
| ECF_NORETURN
))
2261 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
)))
2262 /* If the called function is nested in the current one, it might access
2263 some of the caller's arguments, but could clobber them beforehand if
2264 the argument areas are shared. */
2265 || (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
2266 /* If this function requires more stack slots than the current
2267 function, we cannot change it into a sibling call.
2268 current_function_pretend_args_size is not part of the
2269 stack allocated by our caller. */
2270 || args_size
.constant
> (current_function_args_size
2271 - current_function_pretend_args_size
)
2272 /* If the callee pops its own arguments, then it must pop exactly
2273 the same number of arguments as the current function. */
2274 || (RETURN_POPS_ARGS (fndecl
, funtype
, args_size
.constant
)
2275 != RETURN_POPS_ARGS (current_function_decl
,
2276 TREE_TYPE (current_function_decl
),
2277 current_function_args_size
))
2278 || !lang_hooks
.decls
.ok_for_sibcall (fndecl
))
2281 /* Ensure current function's preferred stack boundary is at least
2282 what we need. We don't have to increase alignment for recursive
2284 if (cfun
->preferred_stack_boundary
< preferred_stack_boundary
2285 && fndecl
!= current_function_decl
)
2286 cfun
->preferred_stack_boundary
= preferred_stack_boundary
;
2287 if (fndecl
== current_function_decl
)
2288 cfun
->recursive_call_emit
= true;
2290 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2292 /* We want to make two insn chains; one for a sibling call, the other
2293 for a normal call. We will select one of the two chains after
2294 initial RTL generation is complete. */
2295 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
2297 int sibcall_failure
= 0;
2298 /* We want to emit any pending stack adjustments before the tail
2299 recursion "call". That way we know any adjustment after the tail
2300 recursion call can be ignored if we indeed use the tail
2302 int save_pending_stack_adjust
= 0;
2303 int save_stack_pointer_delta
= 0;
2305 rtx before_call
, next_arg_reg
;
2309 /* State variables we need to save and restore between
2311 save_pending_stack_adjust
= pending_stack_adjust
;
2312 save_stack_pointer_delta
= stack_pointer_delta
;
2315 flags
&= ~ECF_SIBCALL
;
2317 flags
|= ECF_SIBCALL
;
2319 /* Other state variables that we must reinitialize each time
2320 through the loop (that are not initialized by the loop itself). */
2324 /* Start a new sequence for the normal call case.
2326 From this point on, if the sibling call fails, we want to set
2327 sibcall_failure instead of continuing the loop. */
2330 /* Don't let pending stack adjusts add up to too much.
2331 Also, do all pending adjustments now if there is any chance
2332 this might be a call to alloca or if we are expanding a sibling
2333 call sequence or if we are calling a function that is to return
2334 with stack pointer depressed.
2335 Also do the adjustments before a throwing call, otherwise
2336 exception handling can fail; PR 19225. */
2337 if (pending_stack_adjust
>= 32
2338 || (pending_stack_adjust
> 0
2339 && (flags
& (ECF_MAY_BE_ALLOCA
| ECF_SP_DEPRESSED
)))
2340 || (pending_stack_adjust
> 0
2341 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
2343 do_pending_stack_adjust ();
2345 /* When calling a const function, we must pop the stack args right away,
2346 so that the pop is deleted or moved with the call. */
2347 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
2350 /* Precompute any arguments as needed. */
2352 precompute_arguments (flags
, num_actuals
, args
);
2354 /* Now we are about to start emitting insns that can be deleted
2355 if a libcall is deleted. */
2356 if (pass
&& (flags
& (ECF_LIBCALL_BLOCK
| ECF_MALLOC
)))
2359 if (pass
== 0 && cfun
->stack_protect_guard
)
2360 stack_protect_epilogue ();
2362 adjusted_args_size
= args_size
;
2363 /* Compute the actual size of the argument block required. The variable
2364 and constant sizes must be combined, the size may have to be rounded,
2365 and there may be a minimum required size. When generating a sibcall
2366 pattern, do not round up, since we'll be re-using whatever space our
2368 unadjusted_args_size
2369 = compute_argument_block_size (reg_parm_stack_space
,
2370 &adjusted_args_size
,
2372 : preferred_stack_boundary
));
2374 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2376 /* The argument block when performing a sibling call is the
2377 incoming argument block. */
2380 argblock
= virtual_incoming_args_rtx
;
2382 #ifdef STACK_GROWS_DOWNWARD
2383 = plus_constant (argblock
, current_function_pretend_args_size
);
2385 = plus_constant (argblock
, -current_function_pretend_args_size
);
2387 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2388 sbitmap_zero (stored_args_map
);
2391 /* If we have no actual push instructions, or shouldn't use them,
2392 make space for all args right now. */
2393 else if (adjusted_args_size
.var
!= 0)
2395 if (old_stack_level
== 0)
2397 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
2398 old_stack_pointer_delta
= stack_pointer_delta
;
2399 old_pending_adj
= pending_stack_adjust
;
2400 pending_stack_adjust
= 0;
2401 /* stack_arg_under_construction says whether a stack arg is
2402 being constructed at the old stack level. Pushing the stack
2403 gets a clean outgoing argument block. */
2404 old_stack_arg_under_construction
= stack_arg_under_construction
;
2405 stack_arg_under_construction
= 0;
2407 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2411 /* Note that we must go through the motions of allocating an argument
2412 block even if the size is zero because we may be storing args
2413 in the area reserved for register arguments, which may be part of
2416 int needed
= adjusted_args_size
.constant
;
2418 /* Store the maximum argument space used. It will be pushed by
2419 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2422 if (needed
> current_function_outgoing_args_size
)
2423 current_function_outgoing_args_size
= needed
;
2425 if (must_preallocate
)
2427 if (ACCUMULATE_OUTGOING_ARGS
)
2429 /* Since the stack pointer will never be pushed, it is
2430 possible for the evaluation of a parm to clobber
2431 something we have already written to the stack.
2432 Since most function calls on RISC machines do not use
2433 the stack, this is uncommon, but must work correctly.
2435 Therefore, we save any area of the stack that was already
2436 written and that we are using. Here we set up to do this
2437 by making a new stack usage map from the old one. The
2438 actual save will be done by store_one_arg.
2440 Another approach might be to try to reorder the argument
2441 evaluations to avoid this conflicting stack usage. */
2443 /* Since we will be writing into the entire argument area,
2444 the map must be allocated for its entire size, not just
2445 the part that is the responsibility of the caller. */
2446 if (!OUTGOING_REG_PARM_STACK_SPACE
)
2447 needed
+= reg_parm_stack_space
;
2449 #ifdef ARGS_GROW_DOWNWARD
2450 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2453 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2456 if (stack_usage_map_buf
)
2457 free (stack_usage_map_buf
);
2458 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
2459 stack_usage_map
= stack_usage_map_buf
;
2461 if (initial_highest_arg_in_use
)
2462 memcpy (stack_usage_map
, initial_stack_usage_map
,
2463 initial_highest_arg_in_use
);
2465 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2466 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2467 (highest_outgoing_arg_in_use
2468 - initial_highest_arg_in_use
));
2471 /* The address of the outgoing argument list must not be
2472 copied to a register here, because argblock would be left
2473 pointing to the wrong place after the call to
2474 allocate_dynamic_stack_space below. */
2476 argblock
= virtual_outgoing_args_rtx
;
2480 if (inhibit_defer_pop
== 0)
2482 /* Try to reuse some or all of the pending_stack_adjust
2483 to get this space. */
2485 = (combine_pending_stack_adjustment_and_call
2486 (unadjusted_args_size
,
2487 &adjusted_args_size
,
2488 preferred_unit_stack_boundary
));
2490 /* combine_pending_stack_adjustment_and_call computes
2491 an adjustment before the arguments are allocated.
2492 Account for them and see whether or not the stack
2493 needs to go up or down. */
2494 needed
= unadjusted_args_size
- needed
;
2498 /* We're releasing stack space. */
2499 /* ??? We can avoid any adjustment at all if we're
2500 already aligned. FIXME. */
2501 pending_stack_adjust
= -needed
;
2502 do_pending_stack_adjust ();
2506 /* We need to allocate space. We'll do that in
2507 push_block below. */
2508 pending_stack_adjust
= 0;
2511 /* Special case this because overhead of `push_block' in
2512 this case is non-trivial. */
2514 argblock
= virtual_outgoing_args_rtx
;
2517 argblock
= push_block (GEN_INT (needed
), 0, 0);
2518 #ifdef ARGS_GROW_DOWNWARD
2519 argblock
= plus_constant (argblock
, needed
);
2523 /* We only really need to call `copy_to_reg' in the case
2524 where push insns are going to be used to pass ARGBLOCK
2525 to a function call in ARGS. In that case, the stack
2526 pointer changes value from the allocation point to the
2527 call point, and hence the value of
2528 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2529 as well always do it. */
2530 argblock
= copy_to_reg (argblock
);
2535 if (ACCUMULATE_OUTGOING_ARGS
)
2537 /* The save/restore code in store_one_arg handles all
2538 cases except one: a constructor call (including a C
2539 function returning a BLKmode struct) to initialize
2541 if (stack_arg_under_construction
)
2544 = GEN_INT (adjusted_args_size
.constant
2545 + (OUTGOING_REG_PARM_STACK_SPACE
? 0
2546 : reg_parm_stack_space
));
2547 if (old_stack_level
== 0)
2549 emit_stack_save (SAVE_BLOCK
, &old_stack_level
,
2551 old_stack_pointer_delta
= stack_pointer_delta
;
2552 old_pending_adj
= pending_stack_adjust
;
2553 pending_stack_adjust
= 0;
2554 /* stack_arg_under_construction says whether a stack
2555 arg is being constructed at the old stack level.
2556 Pushing the stack gets a clean outgoing argument
2558 old_stack_arg_under_construction
2559 = stack_arg_under_construction
;
2560 stack_arg_under_construction
= 0;
2561 /* Make a new map for the new argument list. */
2562 if (stack_usage_map_buf
)
2563 free (stack_usage_map_buf
);
2564 stack_usage_map_buf
= XCNEWVEC (char, highest_outgoing_arg_in_use
);
2565 stack_usage_map
= stack_usage_map_buf
;
2566 highest_outgoing_arg_in_use
= 0;
2568 allocate_dynamic_stack_space (push_size
, NULL_RTX
,
2572 /* If argument evaluation might modify the stack pointer,
2573 copy the address of the argument list to a register. */
2574 for (i
= 0; i
< num_actuals
; i
++)
2575 if (args
[i
].pass_on_stack
)
2577 argblock
= copy_addr_to_reg (argblock
);
2582 compute_argument_addresses (args
, argblock
, num_actuals
);
2584 /* If we push args individually in reverse order, perform stack alignment
2585 before the first push (the last arg). */
2586 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2587 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2589 /* When the stack adjustment is pending, we get better code
2590 by combining the adjustments. */
2591 if (pending_stack_adjust
2592 && ! (flags
& ECF_LIBCALL_BLOCK
)
2593 && ! inhibit_defer_pop
)
2595 pending_stack_adjust
2596 = (combine_pending_stack_adjustment_and_call
2597 (unadjusted_args_size
,
2598 &adjusted_args_size
,
2599 preferred_unit_stack_boundary
));
2600 do_pending_stack_adjust ();
2602 else if (argblock
== 0)
2603 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2604 - unadjusted_args_size
));
2606 /* Now that the stack is properly aligned, pops can't safely
2607 be deferred during the evaluation of the arguments. */
2610 funexp
= rtx_for_function_call (fndecl
, addr
);
2612 /* Figure out the register where the value, if any, will come back. */
2614 if (TYPE_MODE (TREE_TYPE (exp
)) != VOIDmode
2615 && ! structure_value_addr
)
2617 if (pcc_struct_value
)
2618 valreg
= hard_function_value (build_pointer_type (TREE_TYPE (exp
)),
2619 fndecl
, NULL
, (pass
== 0));
2621 valreg
= hard_function_value (TREE_TYPE (exp
), fndecl
, fntype
,
2624 /* If VALREG is a PARALLEL whose first member has a zero
2625 offset, use that. This is for targets such as m68k that
2626 return the same value in multiple places. */
2627 if (GET_CODE (valreg
) == PARALLEL
)
2629 rtx elem
= XVECEXP (valreg
, 0, 0);
2630 rtx where
= XEXP (elem
, 0);
2631 rtx offset
= XEXP (elem
, 1);
2632 if (offset
== const0_rtx
2633 && GET_MODE (where
) == GET_MODE (valreg
))
2638 /* Precompute all register parameters. It isn't safe to compute anything
2639 once we have started filling any specific hard regs. */
2640 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2642 if (CALL_EXPR_STATIC_CHAIN (exp
))
2643 static_chain_value
= expand_normal (CALL_EXPR_STATIC_CHAIN (exp
));
2645 static_chain_value
= 0;
2647 #ifdef REG_PARM_STACK_SPACE
2648 /* Save the fixed argument area if it's part of the caller's frame and
2649 is clobbered by argument setup for this call. */
2650 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2651 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2652 &low_to_save
, &high_to_save
);
2655 /* Now store (and compute if necessary) all non-register parms.
2656 These come before register parms, since they can require block-moves,
2657 which could clobber the registers used for register parms.
2658 Parms which have partial registers are not stored here,
2659 but we do preallocate space here if they want that. */
2661 for (i
= 0; i
< num_actuals
; i
++)
2662 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2664 rtx before_arg
= get_last_insn ();
2666 if (store_one_arg (&args
[i
], argblock
, flags
,
2667 adjusted_args_size
.var
!= 0,
2668 reg_parm_stack_space
)
2670 && check_sibcall_argument_overlap (before_arg
,
2672 sibcall_failure
= 1;
2674 if (flags
& ECF_CONST
2676 && args
[i
].value
== args
[i
].stack
)
2677 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
2678 gen_rtx_USE (VOIDmode
,
2683 /* If we have a parm that is passed in registers but not in memory
2684 and whose alignment does not permit a direct copy into registers,
2685 make a group of pseudos that correspond to each register that we
2687 if (STRICT_ALIGNMENT
)
2688 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2690 /* Now store any partially-in-registers parm.
2691 This is the last place a block-move can happen. */
2693 for (i
= 0; i
< num_actuals
; i
++)
2694 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2696 rtx before_arg
= get_last_insn ();
2698 if (store_one_arg (&args
[i
], argblock
, flags
,
2699 adjusted_args_size
.var
!= 0,
2700 reg_parm_stack_space
)
2702 && check_sibcall_argument_overlap (before_arg
,
2704 sibcall_failure
= 1;
2707 /* If we pushed args in forward order, perform stack alignment
2708 after pushing the last arg. */
2709 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
2710 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2711 - unadjusted_args_size
));
2713 /* If register arguments require space on the stack and stack space
2714 was not preallocated, allocate stack space here for arguments
2715 passed in registers. */
2716 if (OUTGOING_REG_PARM_STACK_SPACE
&& !ACCUMULATE_OUTGOING_ARGS
2717 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
2718 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
2720 /* Pass the function the address in which to return a
2722 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
2724 structure_value_addr
2725 = convert_memory_address (Pmode
, structure_value_addr
);
2726 emit_move_insn (struct_value
,
2728 force_operand (structure_value_addr
,
2731 if (REG_P (struct_value
))
2732 use_reg (&call_fusage
, struct_value
);
2735 funexp
= prepare_call_address (funexp
, static_chain_value
,
2736 &call_fusage
, reg_parm_seen
, pass
== 0);
2738 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
2739 pass
== 0, &sibcall_failure
);
2741 /* Save a pointer to the last insn before the call, so that we can
2742 later safely search backwards to find the CALL_INSN. */
2743 before_call
= get_last_insn ();
2745 /* Set up next argument register. For sibling calls on machines
2746 with register windows this should be the incoming register. */
2747 #ifdef FUNCTION_INCOMING_ARG
2749 next_arg_reg
= FUNCTION_INCOMING_ARG (args_so_far
, VOIDmode
,
2753 next_arg_reg
= FUNCTION_ARG (args_so_far
, VOIDmode
,
2756 /* All arguments and registers used for the call must be set up by
2759 /* Stack must be properly aligned now. */
2761 || !(stack_pointer_delta
% preferred_unit_stack_boundary
));
2763 /* Generate the actual call instruction. */
2764 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
2765 adjusted_args_size
.constant
, struct_value_size
,
2766 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
2767 flags
, & args_so_far
);
2769 /* If a non-BLKmode value is returned at the most significant end
2770 of a register, shift the register right by the appropriate amount
2771 and update VALREG accordingly. BLKmode values are handled by the
2772 group load/store machinery below. */
2773 if (!structure_value_addr
2774 && !pcc_struct_value
2775 && TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
2776 && targetm
.calls
.return_in_msb (TREE_TYPE (exp
)))
2778 if (shift_return_value (TYPE_MODE (TREE_TYPE (exp
)), false, valreg
))
2779 sibcall_failure
= 1;
2780 valreg
= gen_rtx_REG (TYPE_MODE (TREE_TYPE (exp
)), REGNO (valreg
));
2783 /* If call is cse'able, make appropriate pair of reg-notes around it.
2784 Test valreg so we don't crash; may safely ignore `const'
2785 if return type is void. Disable for PARALLEL return values, because
2786 we have no way to move such values into a pseudo register. */
2787 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
2791 bool failed
= valreg
== 0 || GET_CODE (valreg
) == PARALLEL
;
2793 insns
= get_insns ();
2795 /* Expansion of block moves possibly introduced a loop that may
2796 not appear inside libcall block. */
2797 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
2809 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2811 /* Mark the return value as a pointer if needed. */
2812 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
2813 mark_reg_pointer (temp
,
2814 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp
))));
2817 if (flag_unsafe_math_optimizations
2819 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
2820 && (DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRT
2821 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRTF
2822 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRTL
))
2823 note
= gen_rtx_fmt_e (SQRT
,
2825 args
[0].initial_value
);
2828 /* Construct an "equal form" for the value which
2829 mentions all the arguments in order as well as
2830 the function name. */
2831 for (i
= 0; i
< num_actuals
; i
++)
2832 note
= gen_rtx_EXPR_LIST (VOIDmode
,
2833 args
[i
].initial_value
, note
);
2834 note
= gen_rtx_EXPR_LIST (VOIDmode
, funexp
, note
);
2836 if (flags
& ECF_PURE
)
2837 note
= gen_rtx_EXPR_LIST (VOIDmode
,
2838 gen_rtx_USE (VOIDmode
,
2839 gen_rtx_MEM (BLKmode
,
2840 gen_rtx_SCRATCH (VOIDmode
))),
2843 emit_libcall_block (insns
, temp
, valreg
, note
);
2848 else if (pass
&& (flags
& ECF_MALLOC
))
2850 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2853 /* The return value from a malloc-like function is a pointer. */
2854 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
2855 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
2857 emit_move_insn (temp
, valreg
);
2859 /* The return value from a malloc-like function can not alias
2861 last
= get_last_insn ();
2863 gen_rtx_EXPR_LIST (REG_NOALIAS
, temp
, REG_NOTES (last
));
2865 /* Write out the sequence. */
2866 insns
= get_insns ();
2872 /* For calls to `setjmp', etc., inform
2873 function.c:setjmp_warnings that it should complain if
2874 nonvolatile values are live. For functions that cannot
2875 return, inform flow that control does not fall through. */
2877 if ((flags
& ECF_NORETURN
) || pass
== 0)
2879 /* The barrier must be emitted
2880 immediately after the CALL_INSN. Some ports emit more
2881 than just a CALL_INSN above, so we must search for it here. */
2883 rtx last
= get_last_insn ();
2884 while (!CALL_P (last
))
2886 last
= PREV_INSN (last
);
2887 /* There was no CALL_INSN? */
2888 gcc_assert (last
!= before_call
);
2891 emit_barrier_after (last
);
2893 /* Stack adjustments after a noreturn call are dead code.
2894 However when NO_DEFER_POP is in effect, we must preserve
2895 stack_pointer_delta. */
2896 if (inhibit_defer_pop
== 0)
2898 stack_pointer_delta
= old_stack_allocated
;
2899 pending_stack_adjust
= 0;
2903 /* If value type not void, return an rtx for the value. */
2905 if (TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
2907 target
= const0_rtx
;
2908 else if (structure_value_addr
)
2910 if (target
== 0 || !MEM_P (target
))
2913 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
2914 memory_address (TYPE_MODE (TREE_TYPE (exp
)),
2915 structure_value_addr
));
2916 set_mem_attributes (target
, exp
, 1);
2919 else if (pcc_struct_value
)
2921 /* This is the special C++ case where we need to
2922 know what the true target was. We take care to
2923 never use this value more than once in one expression. */
2924 target
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
2925 copy_to_reg (valreg
));
2926 set_mem_attributes (target
, exp
, 1);
2928 /* Handle calls that return values in multiple non-contiguous locations.
2929 The Irix 6 ABI has examples of this. */
2930 else if (GET_CODE (valreg
) == PARALLEL
)
2934 /* This will only be assigned once, so it can be readonly. */
2935 tree nt
= build_qualified_type (TREE_TYPE (exp
),
2936 (TYPE_QUALS (TREE_TYPE (exp
))
2937 | TYPE_QUAL_CONST
));
2939 target
= assign_temp (nt
, 0, 1, 1);
2942 if (! rtx_equal_p (target
, valreg
))
2943 emit_group_store (target
, valreg
, TREE_TYPE (exp
),
2944 int_size_in_bytes (TREE_TYPE (exp
)));
2946 /* We can not support sibling calls for this case. */
2947 sibcall_failure
= 1;
2950 && GET_MODE (target
) == TYPE_MODE (TREE_TYPE (exp
))
2951 && GET_MODE (target
) == GET_MODE (valreg
))
2953 bool may_overlap
= false;
2955 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
2956 reg to a plain register. */
2958 && HARD_REGISTER_P (valreg
)
2959 && CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (REGNO (valreg
)))
2960 && !(REG_P (target
) && !HARD_REGISTER_P (target
)))
2961 valreg
= copy_to_reg (valreg
);
2963 /* If TARGET is a MEM in the argument area, and we have
2964 saved part of the argument area, then we can't store
2965 directly into TARGET as it may get overwritten when we
2966 restore the argument save area below. Don't work too
2967 hard though and simply force TARGET to a register if it
2968 is a MEM; the optimizer is quite likely to sort it out. */
2969 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
2970 for (i
= 0; i
< num_actuals
; i
++)
2971 if (args
[i
].save_area
)
2978 target
= copy_to_reg (valreg
);
2981 /* TARGET and VALREG cannot be equal at this point
2982 because the latter would not have
2983 REG_FUNCTION_VALUE_P true, while the former would if
2984 it were referring to the same register.
2986 If they refer to the same register, this move will be
2987 a no-op, except when function inlining is being
2989 emit_move_insn (target
, valreg
);
2991 /* If we are setting a MEM, this code must be executed.
2992 Since it is emitted after the call insn, sibcall
2993 optimization cannot be performed in that case. */
2995 sibcall_failure
= 1;
2998 else if (TYPE_MODE (TREE_TYPE (exp
)) == BLKmode
)
3000 target
= copy_blkmode_from_reg (target
, valreg
, TREE_TYPE (exp
));
3002 /* We can not support sibling calls for this case. */
3003 sibcall_failure
= 1;
3006 target
= copy_to_reg (valreg
);
3008 if (targetm
.calls
.promote_function_return(funtype
))
3010 /* If we promoted this return value, make the proper SUBREG.
3011 TARGET might be const0_rtx here, so be careful. */
3013 && TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
3014 && GET_MODE (target
) != TYPE_MODE (TREE_TYPE (exp
)))
3016 tree type
= TREE_TYPE (exp
);
3017 int unsignedp
= TYPE_UNSIGNED (type
);
3019 enum machine_mode pmode
;
3021 pmode
= promote_mode (type
, TYPE_MODE (type
), &unsignedp
, 1);
3022 /* If we don't promote as expected, something is wrong. */
3023 gcc_assert (GET_MODE (target
) == pmode
);
3025 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
3026 && (GET_MODE_SIZE (GET_MODE (target
))
3027 > GET_MODE_SIZE (TYPE_MODE (type
))))
3029 offset
= GET_MODE_SIZE (GET_MODE (target
))
3030 - GET_MODE_SIZE (TYPE_MODE (type
));
3031 if (! BYTES_BIG_ENDIAN
)
3032 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
3033 else if (! WORDS_BIG_ENDIAN
)
3034 offset
%= UNITS_PER_WORD
;
3036 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
3037 SUBREG_PROMOTED_VAR_P (target
) = 1;
3038 SUBREG_PROMOTED_UNSIGNED_SET (target
, unsignedp
);
3042 /* If size of args is variable or this was a constructor call for a stack
3043 argument, restore saved stack-pointer value. */
3045 if (old_stack_level
&& ! (flags
& ECF_SP_DEPRESSED
))
3047 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
3048 stack_pointer_delta
= old_stack_pointer_delta
;
3049 pending_stack_adjust
= old_pending_adj
;
3050 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
3051 stack_arg_under_construction
= old_stack_arg_under_construction
;
3052 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3053 stack_usage_map
= initial_stack_usage_map
;
3054 sibcall_failure
= 1;
3056 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
3058 #ifdef REG_PARM_STACK_SPACE
3060 restore_fixed_argument_area (save_area
, argblock
,
3061 high_to_save
, low_to_save
);
3064 /* If we saved any argument areas, restore them. */
3065 for (i
= 0; i
< num_actuals
; i
++)
3066 if (args
[i
].save_area
)
3068 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
3070 = gen_rtx_MEM (save_mode
,
3071 memory_address (save_mode
,
3072 XEXP (args
[i
].stack_slot
, 0)));
3074 if (save_mode
!= BLKmode
)
3075 emit_move_insn (stack_area
, args
[i
].save_area
);
3077 emit_block_move (stack_area
, args
[i
].save_area
,
3078 GEN_INT (args
[i
].locate
.size
.constant
),
3079 BLOCK_OP_CALL_PARM
);
3082 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3083 stack_usage_map
= initial_stack_usage_map
;
3086 /* If this was alloca, record the new stack level for nonlocal gotos.
3087 Check for the handler slots since we might not have a save area
3088 for non-local gotos. */
3090 if ((flags
& ECF_MAY_BE_ALLOCA
) && cfun
->nonlocal_goto_save_area
!= 0)
3091 update_nonlocal_goto_save_area ();
3093 /* Free up storage we no longer need. */
3094 for (i
= 0; i
< num_actuals
; ++i
)
3095 if (args
[i
].aligned_regs
)
3096 free (args
[i
].aligned_regs
);
3098 insns
= get_insns ();
3103 tail_call_insns
= insns
;
3105 /* Restore the pending stack adjustment now that we have
3106 finished generating the sibling call sequence. */
3108 pending_stack_adjust
= save_pending_stack_adjust
;
3109 stack_pointer_delta
= save_stack_pointer_delta
;
3111 /* Prepare arg structure for next iteration. */
3112 for (i
= 0; i
< num_actuals
; i
++)
3115 args
[i
].aligned_regs
= 0;
3119 sbitmap_free (stored_args_map
);
3123 normal_call_insns
= insns
;
3125 /* Verify that we've deallocated all the stack we used. */
3126 gcc_assert ((flags
& ECF_NORETURN
)
3127 || (old_stack_allocated
3128 == stack_pointer_delta
- pending_stack_adjust
));
3131 /* If something prevents making this a sibling call,
3132 zero out the sequence. */
3133 if (sibcall_failure
)
3134 tail_call_insns
= NULL_RTX
;
3139 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3140 arguments too, as argument area is now clobbered by the call. */
3141 if (tail_call_insns
)
3143 emit_insn (tail_call_insns
);
3144 cfun
->tail_call_emit
= true;
3147 emit_insn (normal_call_insns
);
3149 currently_expanding_call
--;
3151 /* If this function returns with the stack pointer depressed, ensure
3152 this block saves and restores the stack pointer, show it was
3153 changed, and adjust for any outgoing arg space. */
3154 if (flags
& ECF_SP_DEPRESSED
)
3156 clear_pending_stack_adjust ();
3157 emit_insn (gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
));
3158 emit_move_insn (virtual_stack_dynamic_rtx
, stack_pointer_rtx
);
3161 if (stack_usage_map_buf
)
3162 free (stack_usage_map_buf
);
3167 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3168 this function's incoming arguments.
3170 At the start of RTL generation we know the only REG_EQUIV notes
3171 in the rtl chain are those for incoming arguments, so we can look
3172 for REG_EQUIV notes between the start of the function and the
3173 NOTE_INSN_FUNCTION_BEG.
3175 This is (slight) overkill. We could keep track of the highest
3176 argument we clobber and be more selective in removing notes, but it
3177 does not seem to be worth the effort. */
3180 fixup_tail_calls (void)
3184 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
3188 /* There are never REG_EQUIV notes for the incoming arguments
3189 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3191 && NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
)
3194 note
= find_reg_note (insn
, REG_EQUIV
, 0);
3196 remove_note (insn
, note
);
3197 note
= find_reg_note (insn
, REG_EQUIV
, 0);
3202 /* Traverse a list of TYPES and expand all complex types into their
3205 split_complex_types (tree types
)
3209 /* Before allocating memory, check for the common case of no complex. */
3210 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3212 tree type
= TREE_VALUE (p
);
3213 if (TREE_CODE (type
) == COMPLEX_TYPE
3214 && targetm
.calls
.split_complex_arg (type
))
3220 types
= copy_list (types
);
3222 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3224 tree complex_type
= TREE_VALUE (p
);
3226 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
3227 && targetm
.calls
.split_complex_arg (complex_type
))
3231 /* Rewrite complex type with component type. */
3232 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
3233 next
= TREE_CHAIN (p
);
3235 /* Add another component type for the imaginary part. */
3236 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
3237 TREE_CHAIN (p
) = imag
;
3238 TREE_CHAIN (imag
) = next
;
3240 /* Skip the newly created node. */
3248 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3249 The RETVAL parameter specifies whether return value needs to be saved, other
3250 parameters are documented in the emit_library_call function below. */
3253 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
3254 enum libcall_type fn_type
,
3255 enum machine_mode outmode
, int nargs
, va_list p
)
3257 /* Total size in bytes of all the stack-parms scanned so far. */
3258 struct args_size args_size
;
3259 /* Size of arguments before any adjustments (such as rounding). */
3260 struct args_size original_args_size
;
3266 CUMULATIVE_ARGS args_so_far
;
3270 enum machine_mode mode
;
3273 struct locate_and_pad_arg_data locate
;
3277 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3278 rtx call_fusage
= 0;
3281 int pcc_struct_value
= 0;
3282 int struct_value_size
= 0;
3284 int reg_parm_stack_space
= 0;
3287 tree tfom
; /* type_for_mode (outmode, 0) */
3289 #ifdef REG_PARM_STACK_SPACE
3290 /* Define the boundary of the register parm stack space that needs to be
3292 int low_to_save
, high_to_save
;
3293 rtx save_area
= 0; /* Place that it is saved. */
3296 /* Size of the stack reserved for parameter registers. */
3297 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3298 char *initial_stack_usage_map
= stack_usage_map
;
3299 char *stack_usage_map_buf
= NULL
;
3301 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
3303 #ifdef REG_PARM_STACK_SPACE
3304 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3307 /* By default, library functions can not throw. */
3308 flags
= ECF_NOTHROW
;
3320 case LCT_CONST_MAKE_BLOCK
:
3321 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
3323 case LCT_PURE_MAKE_BLOCK
:
3324 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
3327 flags
|= ECF_NORETURN
;
3330 flags
= ECF_NORETURN
;
3332 case LCT_RETURNS_TWICE
:
3333 flags
= ECF_RETURNS_TWICE
;
3338 /* Ensure current function's preferred stack boundary is at least
3340 if (cfun
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3341 cfun
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3343 /* If this kind of value comes back in memory,
3344 decide where in memory it should come back. */
3345 if (outmode
!= VOIDmode
)
3347 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
3348 if (aggregate_value_p (tfom
, 0))
3350 #ifdef PCC_STATIC_STRUCT_RETURN
3352 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
3353 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3354 pcc_struct_value
= 1;
3356 value
= gen_reg_rtx (outmode
);
3357 #else /* not PCC_STATIC_STRUCT_RETURN */
3358 struct_value_size
= GET_MODE_SIZE (outmode
);
3359 if (value
!= 0 && MEM_P (value
))
3362 mem_value
= assign_temp (tfom
, 0, 1, 1);
3364 /* This call returns a big structure. */
3365 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3369 tfom
= void_type_node
;
3371 /* ??? Unfinished: must pass the memory address as an argument. */
3373 /* Copy all the libcall-arguments out of the varargs data
3374 and into a vector ARGVEC.
3376 Compute how to pass each argument. We only support a very small subset
3377 of the full argument passing conventions to limit complexity here since
3378 library functions shouldn't have many args. */
3380 argvec
= alloca ((nargs
+ 1) * sizeof (struct arg
));
3381 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3383 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3384 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3386 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0, nargs
);
3389 args_size
.constant
= 0;
3394 /* Now we are about to start emitting insns that can be deleted
3395 if a libcall is deleted. */
3396 if (flags
& ECF_LIBCALL_BLOCK
)
3401 /* If there's a structure value address to be passed,
3402 either pass it in the special place, or pass it as an extra argument. */
3403 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
3405 rtx addr
= XEXP (mem_value
, 0);
3409 /* Make sure it is a reasonable operand for a move or push insn. */
3410 if (!REG_P (addr
) && !MEM_P (addr
)
3411 && ! (CONSTANT_P (addr
) && LEGITIMATE_CONSTANT_P (addr
)))
3412 addr
= force_operand (addr
, NULL_RTX
);
3414 argvec
[count
].value
= addr
;
3415 argvec
[count
].mode
= Pmode
;
3416 argvec
[count
].partial
= 0;
3418 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, Pmode
, NULL_TREE
, 1);
3419 gcc_assert (targetm
.calls
.arg_partial_bytes (&args_so_far
, Pmode
,
3420 NULL_TREE
, 1) == 0);
3422 locate_and_pad_parm (Pmode
, NULL_TREE
,
3423 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3426 argvec
[count
].reg
!= 0,
3428 0, NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3430 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3431 || reg_parm_stack_space
> 0)
3432 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3434 FUNCTION_ARG_ADVANCE (args_so_far
, Pmode
, (tree
) 0, 1);
3439 for (; count
< nargs
; count
++)
3441 rtx val
= va_arg (p
, rtx
);
3442 enum machine_mode mode
= va_arg (p
, enum machine_mode
);
3444 /* We cannot convert the arg value to the mode the library wants here;
3445 must do it earlier where we know the signedness of the arg. */
3446 gcc_assert (mode
!= BLKmode
3447 && (GET_MODE (val
) == mode
|| GET_MODE (val
) == VOIDmode
));
3449 /* Make sure it is a reasonable operand for a move or push insn. */
3450 if (!REG_P (val
) && !MEM_P (val
)
3451 && ! (CONSTANT_P (val
) && LEGITIMATE_CONSTANT_P (val
)))
3452 val
= force_operand (val
, NULL_RTX
);
3454 if (pass_by_reference (&args_so_far
, mode
, NULL_TREE
, 1))
3458 = !reference_callee_copied (&args_so_far
, mode
, NULL_TREE
, 1);
3460 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3461 functions, so we have to pretend this isn't such a function. */
3462 if (flags
& ECF_LIBCALL_BLOCK
)
3464 rtx insns
= get_insns ();
3468 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3470 /* If this was a CONST function, it is now PURE since
3471 it now reads memory. */
3472 if (flags
& ECF_CONST
)
3474 flags
&= ~ECF_CONST
;
3478 if (GET_MODE (val
) == MEM
&& !must_copy
)
3482 slot
= assign_temp (lang_hooks
.types
.type_for_mode (mode
, 0),
3484 emit_move_insn (slot
, val
);
3487 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3488 gen_rtx_USE (VOIDmode
, slot
),
3491 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3492 gen_rtx_CLOBBER (VOIDmode
,
3497 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3500 argvec
[count
].value
= val
;
3501 argvec
[count
].mode
= mode
;
3503 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, mode
, NULL_TREE
, 1);
3505 argvec
[count
].partial
3506 = targetm
.calls
.arg_partial_bytes (&args_so_far
, mode
, NULL_TREE
, 1);
3508 locate_and_pad_parm (mode
, NULL_TREE
,
3509 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3512 argvec
[count
].reg
!= 0,
3514 argvec
[count
].partial
,
3515 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3517 gcc_assert (!argvec
[count
].locate
.size
.var
);
3519 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3520 || reg_parm_stack_space
> 0)
3521 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3523 FUNCTION_ARG_ADVANCE (args_so_far
, mode
, (tree
) 0, 1);
3526 /* If this machine requires an external definition for library
3527 functions, write one out. */
3528 assemble_external_libcall (fun
);
3530 original_args_size
= args_size
;
3531 args_size
.constant
= (((args_size
.constant
3532 + stack_pointer_delta
3536 - stack_pointer_delta
);
3538 args_size
.constant
= MAX (args_size
.constant
,
3539 reg_parm_stack_space
);
3541 if (!OUTGOING_REG_PARM_STACK_SPACE
)
3542 args_size
.constant
-= reg_parm_stack_space
;
3544 if (args_size
.constant
> current_function_outgoing_args_size
)
3545 current_function_outgoing_args_size
= args_size
.constant
;
3547 if (ACCUMULATE_OUTGOING_ARGS
)
3549 /* Since the stack pointer will never be pushed, it is possible for
3550 the evaluation of a parm to clobber something we have already
3551 written to the stack. Since most function calls on RISC machines
3552 do not use the stack, this is uncommon, but must work correctly.
3554 Therefore, we save any area of the stack that was already written
3555 and that we are using. Here we set up to do this by making a new
3556 stack usage map from the old one.
3558 Another approach might be to try to reorder the argument
3559 evaluations to avoid this conflicting stack usage. */
3561 needed
= args_size
.constant
;
3563 /* Since we will be writing into the entire argument area, the
3564 map must be allocated for its entire size, not just the part that
3565 is the responsibility of the caller. */
3566 if (!OUTGOING_REG_PARM_STACK_SPACE
)
3567 needed
+= reg_parm_stack_space
;
3569 #ifdef ARGS_GROW_DOWNWARD
3570 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3573 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3576 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
3577 stack_usage_map
= stack_usage_map_buf
;
3579 if (initial_highest_arg_in_use
)
3580 memcpy (stack_usage_map
, initial_stack_usage_map
,
3581 initial_highest_arg_in_use
);
3583 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3584 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3585 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3588 /* We must be careful to use virtual regs before they're instantiated,
3589 and real regs afterwards. Loop optimization, for example, can create
3590 new libcalls after we've instantiated the virtual regs, and if we
3591 use virtuals anyway, they won't match the rtl patterns. */
3593 if (virtuals_instantiated
)
3594 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3596 argblock
= virtual_outgoing_args_rtx
;
3601 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3604 /* If we push args individually in reverse order, perform stack alignment
3605 before the first push (the last arg). */
3606 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3607 anti_adjust_stack (GEN_INT (args_size
.constant
3608 - original_args_size
.constant
));
3610 if (PUSH_ARGS_REVERSED
)
3621 #ifdef REG_PARM_STACK_SPACE
3622 if (ACCUMULATE_OUTGOING_ARGS
)
3624 /* The argument list is the property of the called routine and it
3625 may clobber it. If the fixed area has been used for previous
3626 parameters, we must save and restore it. */
3627 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
3628 &low_to_save
, &high_to_save
);
3632 /* Push the args that need to be pushed. */
3634 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3635 are to be pushed. */
3636 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3638 enum machine_mode mode
= argvec
[argnum
].mode
;
3639 rtx val
= argvec
[argnum
].value
;
3640 rtx reg
= argvec
[argnum
].reg
;
3641 int partial
= argvec
[argnum
].partial
;
3642 int lower_bound
= 0, upper_bound
= 0, i
;
3644 if (! (reg
!= 0 && partial
== 0))
3646 if (ACCUMULATE_OUTGOING_ARGS
)
3648 /* If this is being stored into a pre-allocated, fixed-size,
3649 stack area, save any previous data at that location. */
3651 #ifdef ARGS_GROW_DOWNWARD
3652 /* stack_slot is negative, but we want to index stack_usage_map
3653 with positive values. */
3654 upper_bound
= -argvec
[argnum
].locate
.offset
.constant
+ 1;
3655 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
3657 lower_bound
= argvec
[argnum
].locate
.offset
.constant
;
3658 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
3662 /* Don't worry about things in the fixed argument area;
3663 it has already been saved. */
3664 if (i
< reg_parm_stack_space
)
3665 i
= reg_parm_stack_space
;
3666 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
3669 if (i
< upper_bound
)
3671 /* We need to make a save area. */
3673 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
3674 enum machine_mode save_mode
3675 = mode_for_size (size
, MODE_INT
, 1);
3677 = plus_constant (argblock
,
3678 argvec
[argnum
].locate
.offset
.constant
);
3680 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
3682 if (save_mode
== BLKmode
)
3684 argvec
[argnum
].save_area
3685 = assign_stack_temp (BLKmode
,
3686 argvec
[argnum
].locate
.size
.constant
,
3689 emit_block_move (validize_mem (argvec
[argnum
].save_area
),
3691 GEN_INT (argvec
[argnum
].locate
.size
.constant
),
3692 BLOCK_OP_CALL_PARM
);
3696 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3698 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3703 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, PARM_BOUNDARY
,
3704 partial
, reg
, 0, argblock
,
3705 GEN_INT (argvec
[argnum
].locate
.offset
.constant
),
3706 reg_parm_stack_space
,
3707 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
));
3709 /* Now mark the segment we just used. */
3710 if (ACCUMULATE_OUTGOING_ARGS
)
3711 for (i
= lower_bound
; i
< upper_bound
; i
++)
3712 stack_usage_map
[i
] = 1;
3716 if (flags
& ECF_CONST
)
3720 /* Indicate argument access so that alias.c knows that these
3723 use
= plus_constant (argblock
,
3724 argvec
[argnum
].locate
.offset
.constant
);
3726 /* When arguments are pushed, trying to tell alias.c where
3727 exactly this argument is won't work, because the
3728 auto-increment causes confusion. So we merely indicate
3729 that we access something with a known mode somewhere on
3731 use
= gen_rtx_PLUS (Pmode
, virtual_outgoing_args_rtx
,
3732 gen_rtx_SCRATCH (Pmode
));
3733 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
3734 use
= gen_rtx_USE (VOIDmode
, use
);
3735 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
3740 /* If we pushed args in forward order, perform stack alignment
3741 after pushing the last arg. */
3742 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3743 anti_adjust_stack (GEN_INT (args_size
.constant
3744 - original_args_size
.constant
));
3746 if (PUSH_ARGS_REVERSED
)
3751 fun
= prepare_call_address (fun
, NULL
, &call_fusage
, 0, 0);
3753 /* Now load any reg parms into their regs. */
3755 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3756 are to be pushed. */
3757 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3759 enum machine_mode mode
= argvec
[argnum
].mode
;
3760 rtx val
= argvec
[argnum
].value
;
3761 rtx reg
= argvec
[argnum
].reg
;
3762 int partial
= argvec
[argnum
].partial
;
3764 /* Handle calls that pass values in multiple non-contiguous
3765 locations. The PA64 has examples of this for library calls. */
3766 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3767 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
3768 else if (reg
!= 0 && partial
== 0)
3769 emit_move_insn (reg
, val
);
3774 /* Any regs containing parms remain in use through the call. */
3775 for (count
= 0; count
< nargs
; count
++)
3777 rtx reg
= argvec
[count
].reg
;
3778 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3779 use_group_regs (&call_fusage
, reg
);
3782 int partial
= argvec
[count
].partial
;
3786 gcc_assert (partial
% UNITS_PER_WORD
== 0);
3787 nregs
= partial
/ UNITS_PER_WORD
;
3788 use_regs (&call_fusage
, REGNO (reg
), nregs
);
3791 use_reg (&call_fusage
, reg
);
3795 /* Pass the function the address in which to return a structure value. */
3796 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
3798 emit_move_insn (struct_value
,
3800 force_operand (XEXP (mem_value
, 0),
3802 if (REG_P (struct_value
))
3803 use_reg (&call_fusage
, struct_value
);
3806 /* Don't allow popping to be deferred, since then
3807 cse'ing of library calls could delete a call and leave the pop. */
3809 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
3810 ? hard_libcall_value (outmode
) : NULL_RTX
);
3812 /* Stack must be properly aligned now. */
3813 gcc_assert (!(stack_pointer_delta
3814 & (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1)));
3816 before_call
= get_last_insn ();
3818 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3819 will set inhibit_defer_pop to that value. */
3820 /* The return type is needed to decide how many bytes the function pops.
3821 Signedness plays no role in that, so for simplicity, we pretend it's
3822 always signed. We also assume that the list of arguments passed has
3823 no impact, so we pretend it is unknown. */
3825 emit_call_1 (fun
, NULL
,
3826 get_identifier (XSTR (orgfun
, 0)),
3827 build_function_type (tfom
, NULL_TREE
),
3828 original_args_size
.constant
, args_size
.constant
,
3830 FUNCTION_ARG (args_so_far
, VOIDmode
, void_type_node
, 1),
3832 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, & args_so_far
);
3834 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
3835 that it should complain if nonvolatile values are live. For
3836 functions that cannot return, inform flow that control does not
3839 if (flags
& ECF_NORETURN
)
3841 /* The barrier note must be emitted
3842 immediately after the CALL_INSN. Some ports emit more than
3843 just a CALL_INSN above, so we must search for it here. */
3845 rtx last
= get_last_insn ();
3846 while (!CALL_P (last
))
3848 last
= PREV_INSN (last
);
3849 /* There was no CALL_INSN? */
3850 gcc_assert (last
!= before_call
);
3853 emit_barrier_after (last
);
3856 /* Now restore inhibit_defer_pop to its actual original value. */
3859 /* If call is cse'able, make appropriate pair of reg-notes around it.
3860 Test valreg so we don't crash; may safely ignore `const'
3861 if return type is void. Disable for PARALLEL return values, because
3862 we have no way to move such values into a pseudo register. */
3863 if (flags
& ECF_LIBCALL_BLOCK
)
3869 insns
= get_insns ();
3879 if (GET_CODE (valreg
) == PARALLEL
)
3881 temp
= gen_reg_rtx (outmode
);
3882 emit_group_store (temp
, valreg
, NULL_TREE
,
3883 GET_MODE_SIZE (outmode
));
3887 temp
= gen_reg_rtx (GET_MODE (valreg
));
3889 /* Construct an "equal form" for the value which mentions all the
3890 arguments in order as well as the function name. */
3891 for (i
= 0; i
< nargs
; i
++)
3892 note
= gen_rtx_EXPR_LIST (VOIDmode
, argvec
[i
].value
, note
);
3893 note
= gen_rtx_EXPR_LIST (VOIDmode
, fun
, note
);
3895 insns
= get_insns ();
3898 if (flags
& ECF_PURE
)
3899 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3900 gen_rtx_USE (VOIDmode
,
3901 gen_rtx_MEM (BLKmode
,
3902 gen_rtx_SCRATCH (VOIDmode
))),
3905 emit_libcall_block (insns
, temp
, valreg
, note
);
3912 /* Copy the value to the right place. */
3913 if (outmode
!= VOIDmode
&& retval
)
3919 if (value
!= mem_value
)
3920 emit_move_insn (value
, mem_value
);
3922 else if (GET_CODE (valreg
) == PARALLEL
)
3925 value
= gen_reg_rtx (outmode
);
3926 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
3930 /* Convert to the proper mode if PROMOTE_MODE has been active. */
3931 if (GET_MODE (valreg
) != outmode
)
3933 int unsignedp
= TYPE_UNSIGNED (tfom
);
3935 gcc_assert (targetm
.calls
.promote_function_return (tfom
));
3936 gcc_assert (promote_mode (tfom
, outmode
, &unsignedp
, 0)
3937 == GET_MODE (valreg
));
3939 valreg
= convert_modes (outmode
, GET_MODE (valreg
), valreg
, 0);
3943 emit_move_insn (value
, valreg
);
3949 if (ACCUMULATE_OUTGOING_ARGS
)
3951 #ifdef REG_PARM_STACK_SPACE
3953 restore_fixed_argument_area (save_area
, argblock
,
3954 high_to_save
, low_to_save
);
3957 /* If we saved any argument areas, restore them. */
3958 for (count
= 0; count
< nargs
; count
++)
3959 if (argvec
[count
].save_area
)
3961 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
3962 rtx adr
= plus_constant (argblock
,
3963 argvec
[count
].locate
.offset
.constant
);
3964 rtx stack_area
= gen_rtx_MEM (save_mode
,
3965 memory_address (save_mode
, adr
));
3967 if (save_mode
== BLKmode
)
3968 emit_block_move (stack_area
,
3969 validize_mem (argvec
[count
].save_area
),
3970 GEN_INT (argvec
[count
].locate
.size
.constant
),
3971 BLOCK_OP_CALL_PARM
);
3973 emit_move_insn (stack_area
, argvec
[count
].save_area
);
3976 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3977 stack_usage_map
= initial_stack_usage_map
;
3980 if (stack_usage_map_buf
)
3981 free (stack_usage_map_buf
);
3987 /* Output a library call to function FUN (a SYMBOL_REF rtx)
3988 (emitting the queue unless NO_QUEUE is nonzero),
3989 for a value of mode OUTMODE,
3990 with NARGS different arguments, passed as alternating rtx values
3991 and machine_modes to convert them to.
3993 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
3994 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
3995 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
3996 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
3997 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
3998 or other LCT_ value for other types of library calls. */
4001 emit_library_call (rtx orgfun
, enum libcall_type fn_type
,
4002 enum machine_mode outmode
, int nargs
, ...)
4006 va_start (p
, nargs
);
4007 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
4011 /* Like emit_library_call except that an extra argument, VALUE,
4012 comes second and says where to store the result.
4013 (If VALUE is zero, this function chooses a convenient way
4014 to return the value.
4016 This function returns an rtx for where the value is to be found.
4017 If VALUE is nonzero, VALUE is returned. */
4020 emit_library_call_value (rtx orgfun
, rtx value
,
4021 enum libcall_type fn_type
,
4022 enum machine_mode outmode
, int nargs
, ...)
4027 va_start (p
, nargs
);
4028 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
4035 /* Store a single argument for a function call
4036 into the register or memory area where it must be passed.
4037 *ARG describes the argument value and where to pass it.
4039 ARGBLOCK is the address of the stack-block for all the arguments,
4040 or 0 on a machine where arguments are pushed individually.
4042 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4043 so must be careful about how the stack is used.
4045 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4046 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4047 that we need not worry about saving and restoring the stack.
4049 FNDECL is the declaration of the function we are calling.
4051 Return nonzero if this arg should cause sibcall failure,
4055 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
4056 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
4058 tree pval
= arg
->tree_value
;
4062 int i
, lower_bound
= 0, upper_bound
= 0;
4063 int sibcall_failure
= 0;
4065 if (TREE_CODE (pval
) == ERROR_MARK
)
4068 /* Push a new temporary level for any temporaries we make for
4072 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4074 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4075 save any previous data at that location. */
4076 if (argblock
&& ! variable_size
&& arg
->stack
)
4078 #ifdef ARGS_GROW_DOWNWARD
4079 /* stack_slot is negative, but we want to index stack_usage_map
4080 with positive values. */
4081 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4082 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4086 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
4088 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4089 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4093 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
4097 /* Don't worry about things in the fixed argument area;
4098 it has already been saved. */
4099 if (i
< reg_parm_stack_space
)
4100 i
= reg_parm_stack_space
;
4101 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
4104 if (i
< upper_bound
)
4106 /* We need to make a save area. */
4107 unsigned int size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
4108 enum machine_mode save_mode
= mode_for_size (size
, MODE_INT
, 1);
4109 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
4110 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
4112 if (save_mode
== BLKmode
)
4114 tree ot
= TREE_TYPE (arg
->tree_value
);
4115 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4116 | TYPE_QUAL_CONST
));
4118 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4119 preserve_temp_slots (arg
->save_area
);
4120 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4121 GEN_INT (arg
->locate
.size
.constant
),
4122 BLOCK_OP_CALL_PARM
);
4126 arg
->save_area
= gen_reg_rtx (save_mode
);
4127 emit_move_insn (arg
->save_area
, stack_area
);
4133 /* If this isn't going to be placed on both the stack and in registers,
4134 set up the register and number of words. */
4135 if (! arg
->pass_on_stack
)
4137 if (flags
& ECF_SIBCALL
)
4138 reg
= arg
->tail_call_reg
;
4141 partial
= arg
->partial
;
4144 /* Being passed entirely in a register. We shouldn't be called in
4146 gcc_assert (reg
== 0 || partial
!= 0);
4148 /* If this arg needs special alignment, don't load the registers
4150 if (arg
->n_aligned_regs
!= 0)
4153 /* If this is being passed partially in a register, we can't evaluate
4154 it directly into its stack slot. Otherwise, we can. */
4155 if (arg
->value
== 0)
4157 /* stack_arg_under_construction is nonzero if a function argument is
4158 being evaluated directly into the outgoing argument list and
4159 expand_call must take special action to preserve the argument list
4160 if it is called recursively.
4162 For scalar function arguments stack_usage_map is sufficient to
4163 determine which stack slots must be saved and restored. Scalar
4164 arguments in general have pass_on_stack == 0.
4166 If this argument is initialized by a function which takes the
4167 address of the argument (a C++ constructor or a C function
4168 returning a BLKmode structure), then stack_usage_map is
4169 insufficient and expand_call must push the stack around the
4170 function call. Such arguments have pass_on_stack == 1.
4172 Note that it is always safe to set stack_arg_under_construction,
4173 but this generates suboptimal code if set when not needed. */
4175 if (arg
->pass_on_stack
)
4176 stack_arg_under_construction
++;
4178 arg
->value
= expand_expr (pval
,
4180 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4181 ? NULL_RTX
: arg
->stack
,
4182 VOIDmode
, EXPAND_STACK_PARM
);
4184 /* If we are promoting object (or for any other reason) the mode
4185 doesn't agree, convert the mode. */
4187 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4188 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4189 arg
->value
, arg
->unsignedp
);
4191 if (arg
->pass_on_stack
)
4192 stack_arg_under_construction
--;
4195 /* Check for overlap with already clobbered argument area. */
4196 if ((flags
& ECF_SIBCALL
)
4197 && MEM_P (arg
->value
)
4198 && mem_overlaps_already_clobbered_arg_p (XEXP (arg
->value
, 0),
4199 arg
->locate
.size
.constant
))
4200 sibcall_failure
= 1;
4202 /* Don't allow anything left on stack from computation
4203 of argument to alloca. */
4204 if (flags
& ECF_MAY_BE_ALLOCA
)
4205 do_pending_stack_adjust ();
4207 if (arg
->value
== arg
->stack
)
4208 /* If the value is already in the stack slot, we are done. */
4210 else if (arg
->mode
!= BLKmode
)
4213 unsigned int parm_align
;
4215 /* Argument is a scalar, not entirely passed in registers.
4216 (If part is passed in registers, arg->partial says how much
4217 and emit_push_insn will take care of putting it there.)
4219 Push it, and if its size is less than the
4220 amount of space allocated to it,
4221 also bump stack pointer by the additional space.
4222 Note that in C the default argument promotions
4223 will prevent such mismatches. */
4225 size
= GET_MODE_SIZE (arg
->mode
);
4226 /* Compute how much space the push instruction will push.
4227 On many machines, pushing a byte will advance the stack
4228 pointer by a halfword. */
4229 #ifdef PUSH_ROUNDING
4230 size
= PUSH_ROUNDING (size
);
4234 /* Compute how much space the argument should get:
4235 round up to a multiple of the alignment for arguments. */
4236 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4237 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4238 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4239 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4241 /* Compute the alignment of the pushed argument. */
4242 parm_align
= arg
->locate
.boundary
;
4243 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4245 int pad
= used
- size
;
4248 unsigned int pad_align
= (pad
& -pad
) * BITS_PER_UNIT
;
4249 parm_align
= MIN (parm_align
, pad_align
);
4253 /* This isn't already where we want it on the stack, so put it there.
4254 This can either be done with push or copy insns. */
4255 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
,
4256 parm_align
, partial
, reg
, used
- size
, argblock
,
4257 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4258 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4260 /* Unless this is a partially-in-register argument, the argument is now
4263 arg
->value
= arg
->stack
;
4267 /* BLKmode, at least partly to be pushed. */
4269 unsigned int parm_align
;
4273 /* Pushing a nonscalar.
4274 If part is passed in registers, PARTIAL says how much
4275 and emit_push_insn will take care of putting it there. */
4277 /* Round its size up to a multiple
4278 of the allocation unit for arguments. */
4280 if (arg
->locate
.size
.var
!= 0)
4283 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
4287 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4288 for BLKmode is careful to avoid it. */
4289 excess
= (arg
->locate
.size
.constant
4290 - int_size_in_bytes (TREE_TYPE (pval
))
4292 size_rtx
= expand_expr (size_in_bytes (TREE_TYPE (pval
)),
4293 NULL_RTX
, TYPE_MODE (sizetype
), 0);
4296 parm_align
= arg
->locate
.boundary
;
4298 /* When an argument is padded down, the block is aligned to
4299 PARM_BOUNDARY, but the actual argument isn't. */
4300 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4302 if (arg
->locate
.size
.var
)
4303 parm_align
= BITS_PER_UNIT
;
4306 unsigned int excess_align
= (excess
& -excess
) * BITS_PER_UNIT
;
4307 parm_align
= MIN (parm_align
, excess_align
);
4311 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
4313 /* emit_push_insn might not work properly if arg->value and
4314 argblock + arg->locate.offset areas overlap. */
4318 if (XEXP (x
, 0) == current_function_internal_arg_pointer
4319 || (GET_CODE (XEXP (x
, 0)) == PLUS
4320 && XEXP (XEXP (x
, 0), 0) ==
4321 current_function_internal_arg_pointer
4322 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
))
4324 if (XEXP (x
, 0) != current_function_internal_arg_pointer
)
4325 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4327 /* expand_call should ensure this. */
4328 gcc_assert (!arg
->locate
.offset
.var
4329 && GET_CODE (size_rtx
) == CONST_INT
);
4331 if (arg
->locate
.offset
.constant
> i
)
4333 if (arg
->locate
.offset
.constant
< i
+ INTVAL (size_rtx
))
4334 sibcall_failure
= 1;
4336 else if (arg
->locate
.offset
.constant
< i
)
4338 if (i
< arg
->locate
.offset
.constant
+ INTVAL (size_rtx
))
4339 sibcall_failure
= 1;
4344 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4345 parm_align
, partial
, reg
, excess
, argblock
,
4346 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4347 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4349 /* Unless this is a partially-in-register argument, the argument is now
4352 ??? Unlike the case above, in which we want the actual
4353 address of the data, so that we can load it directly into a
4354 register, here we want the address of the stack slot, so that
4355 it's properly aligned for word-by-word copying or something
4356 like that. It's not clear that this is always correct. */
4358 arg
->value
= arg
->stack_slot
;
4361 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
4363 tree type
= TREE_TYPE (arg
->tree_value
);
4365 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
4366 int_size_in_bytes (type
));
4369 /* Mark all slots this store used. */
4370 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
4371 && argblock
&& ! variable_size
&& arg
->stack
)
4372 for (i
= lower_bound
; i
< upper_bound
; i
++)
4373 stack_usage_map
[i
] = 1;
4375 /* Once we have pushed something, pops can't safely
4376 be deferred during the rest of the arguments. */
4379 /* Free any temporary slots made in processing this argument. Show
4380 that we might have taken the address of something and pushed that
4382 preserve_temp_slots (NULL_RTX
);
4386 return sibcall_failure
;
4389 /* Nonzero if we do not know how to pass TYPE solely in registers. */
4392 must_pass_in_stack_var_size (enum machine_mode mode ATTRIBUTE_UNUSED
,
4398 /* If the type has variable size... */
4399 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4402 /* If the type is marked as addressable (it is required
4403 to be constructed into the stack)... */
4404 if (TREE_ADDRESSABLE (type
))
4410 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
4411 takes trailing padding of a structure into account. */
4412 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
4415 must_pass_in_stack_var_size_or_pad (enum machine_mode mode
, tree type
)
4420 /* If the type has variable size... */
4421 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4424 /* If the type is marked as addressable (it is required
4425 to be constructed into the stack)... */
4426 if (TREE_ADDRESSABLE (type
))
4429 /* If the padding and mode of the type is such that a copy into
4430 a register would put it into the wrong part of the register. */
4432 && int_size_in_bytes (type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
4433 && (FUNCTION_ARG_PADDING (mode
, type
)
4434 == (BYTES_BIG_ENDIAN
? upward
: downward
)))