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"
45 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
46 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
48 /* Data structure and subroutines used within expand_call. */
52 /* Tree node for this argument. */
54 /* Mode for value; TYPE_MODE unless promoted. */
55 enum machine_mode mode
;
56 /* Current RTL value for argument, or 0 if it isn't precomputed. */
58 /* Initially-compute RTL value for argument; only for const functions. */
60 /* Register to pass this argument in, 0 if passed on stack, or an
61 PARALLEL if the arg is to be copied into multiple non-contiguous
64 /* Register to pass this argument in when generating tail call sequence.
65 This is not the same register as for normal calls on machines with
68 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
69 form for emit_group_move. */
71 /* If REG was promoted from the actual mode of the argument expression,
72 indicates whether the promotion is sign- or zero-extended. */
74 /* Number of bytes to put in registers. 0 means put the whole arg
75 in registers. Also 0 if not passed in registers. */
77 /* Nonzero if argument must be passed on stack.
78 Note that some arguments may be passed on the stack
79 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
80 pass_on_stack identifies arguments that *cannot* go in registers. */
82 /* Some fields packaged up for locate_and_pad_parm. */
83 struct locate_and_pad_arg_data locate
;
84 /* Location on the stack at which parameter should be stored. The store
85 has already been done if STACK == VALUE. */
87 /* Location on the stack of the start of this argument slot. This can
88 differ from STACK if this arg pads downward. This location is known
89 to be aligned to FUNCTION_ARG_BOUNDARY. */
91 /* Place that this stack area has been saved, if needed. */
93 /* If an argument's alignment does not permit direct copying into registers,
94 copy in smaller-sized pieces into pseudos. These are stored in a
95 block pointed to by this field. The next field says how many
96 word-sized pseudos we made. */
101 /* A vector of one char per byte of stack space. A byte if nonzero if
102 the corresponding stack location has been used.
103 This vector is used to prevent a function call within an argument from
104 clobbering any stack already set up. */
105 static char *stack_usage_map
;
107 /* Size of STACK_USAGE_MAP. */
108 static int highest_outgoing_arg_in_use
;
110 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
111 stack location's tail call argument has been already stored into the stack.
112 This bitmap is used to prevent sibling call optimization if function tries
113 to use parent's incoming argument slots when they have been already
114 overwritten with tail call arguments. */
115 static sbitmap stored_args_map
;
117 /* stack_arg_under_construction is nonzero when an argument may be
118 initialized with a constructor call (including a C function that
119 returns a BLKmode struct) and expand_call must take special action
120 to make sure the object being constructed does not overlap the
121 argument list for the constructor call. */
122 static int stack_arg_under_construction
;
124 static void emit_call_1 (rtx
, tree
, tree
, tree
, HOST_WIDE_INT
, HOST_WIDE_INT
,
125 HOST_WIDE_INT
, rtx
, rtx
, int, rtx
, int,
127 static void precompute_register_parameters (int, struct arg_data
*, int *);
128 static int store_one_arg (struct arg_data
*, rtx
, int, int, int);
129 static void store_unaligned_arguments_into_pseudos (struct arg_data
*, int);
130 static int finalize_must_preallocate (int, int, struct arg_data
*,
132 static void precompute_arguments (int, int, struct arg_data
*);
133 static int compute_argument_block_size (int, struct args_size
*, int);
134 static void initialize_argument_information (int, struct arg_data
*,
135 struct args_size
*, int,
137 tree
, CUMULATIVE_ARGS
*, int,
138 rtx
*, int *, int *, int *,
140 static void compute_argument_addresses (struct arg_data
*, rtx
, int);
141 static rtx
rtx_for_function_call (tree
, tree
);
142 static void load_register_parameters (struct arg_data
*, int, rtx
*, int,
144 static rtx
emit_library_call_value_1 (int, rtx
, rtx
, enum libcall_type
,
145 enum machine_mode
, int, va_list);
146 static int special_function_p (tree
, int);
147 static int check_sibcall_argument_overlap_1 (rtx
);
148 static int check_sibcall_argument_overlap (rtx
, struct arg_data
*, int);
150 static int combine_pending_stack_adjustment_and_call (int, struct args_size
*,
152 static tree
split_complex_types (tree
);
154 #ifdef REG_PARM_STACK_SPACE
155 static rtx
save_fixed_argument_area (int, rtx
, int *, int *);
156 static void restore_fixed_argument_area (rtx
, rtx
, int, int);
159 /* Force FUNEXP into a form suitable for the address of a CALL,
160 and return that as an rtx. Also load the static chain register
161 if FNDECL is a nested function.
163 CALL_FUSAGE points to a variable holding the prospective
164 CALL_INSN_FUNCTION_USAGE information. */
167 prepare_call_address (rtx funexp
, rtx static_chain_value
,
168 rtx
*call_fusage
, int reg_parm_seen
, int sibcallp
)
170 /* Make a valid memory address and copy constants through pseudo-regs,
171 but not for a constant address if -fno-function-cse. */
172 if (GET_CODE (funexp
) != SYMBOL_REF
)
173 /* If we are using registers for parameters, force the
174 function address into a register now. */
175 funexp
= ((SMALL_REGISTER_CLASSES
&& reg_parm_seen
)
176 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
177 : memory_address (FUNCTION_MODE
, funexp
));
180 #ifndef NO_FUNCTION_CSE
181 if (optimize
&& ! flag_no_function_cse
)
182 funexp
= force_reg (Pmode
, funexp
);
186 if (static_chain_value
!= 0)
188 static_chain_value
= convert_memory_address (Pmode
, static_chain_value
);
189 emit_move_insn (static_chain_rtx
, static_chain_value
);
191 if (REG_P (static_chain_rtx
))
192 use_reg (call_fusage
, static_chain_rtx
);
198 /* Generate instructions to call function FUNEXP,
199 and optionally pop the results.
200 The CALL_INSN is the first insn generated.
202 FNDECL is the declaration node of the function. This is given to the
203 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
205 FUNTYPE is the data type of the function. This is given to the macro
206 RETURN_POPS_ARGS to determine whether this function pops its own args.
207 We used to allow an identifier for library functions, but that doesn't
208 work when the return type is an aggregate type and the calling convention
209 says that the pointer to this aggregate is to be popped by the callee.
211 STACK_SIZE is the number of bytes of arguments on the stack,
212 ROUNDED_STACK_SIZE is that number rounded up to
213 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
214 both to put into the call insn and to generate explicit popping
217 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
218 It is zero if this call doesn't want a structure value.
220 NEXT_ARG_REG is the rtx that results from executing
221 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
222 just after all the args have had their registers assigned.
223 This could be whatever you like, but normally it is the first
224 arg-register beyond those used for args in this call,
225 or 0 if all the arg-registers are used in this call.
226 It is passed on to `gen_call' so you can put this info in the call insn.
228 VALREG is a hard register in which a value is returned,
229 or 0 if the call does not return a value.
231 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
232 the args to this call were processed.
233 We restore `inhibit_defer_pop' to that value.
235 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
236 denote registers used by the called function. */
239 emit_call_1 (rtx funexp
, tree fntree
, tree fndecl ATTRIBUTE_UNUSED
,
240 tree funtype ATTRIBUTE_UNUSED
,
241 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED
,
242 HOST_WIDE_INT rounded_stack_size
,
243 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED
,
244 rtx next_arg_reg ATTRIBUTE_UNUSED
, rtx valreg
,
245 int old_inhibit_defer_pop
, rtx call_fusage
, int ecf_flags
,
246 CUMULATIVE_ARGS
*args_so_far ATTRIBUTE_UNUSED
)
248 rtx rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
250 int already_popped
= 0;
251 HOST_WIDE_INT n_popped
= RETURN_POPS_ARGS (fndecl
, funtype
, stack_size
);
252 #if defined (HAVE_call) && defined (HAVE_call_value)
253 rtx struct_value_size_rtx
;
254 struct_value_size_rtx
= GEN_INT (struct_value_size
);
257 #ifdef CALL_POPS_ARGS
258 n_popped
+= CALL_POPS_ARGS (* args_so_far
);
261 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
262 and we don't want to load it into a register as an optimization,
263 because prepare_call_address already did it if it should be done. */
264 if (GET_CODE (funexp
) != SYMBOL_REF
)
265 funexp
= memory_address (FUNCTION_MODE
, funexp
);
267 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
268 if ((ecf_flags
& ECF_SIBCALL
)
269 && HAVE_sibcall_pop
&& HAVE_sibcall_value_pop
270 && (n_popped
> 0 || stack_size
== 0))
272 rtx n_pop
= GEN_INT (n_popped
);
275 /* If this subroutine pops its own args, record that in the call insn
276 if possible, for the sake of frame pointer elimination. */
279 pat
= GEN_SIBCALL_VALUE_POP (valreg
,
280 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
281 rounded_stack_size_rtx
, next_arg_reg
,
284 pat
= GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
285 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
287 emit_call_insn (pat
);
293 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
294 /* If the target has "call" or "call_value" insns, then prefer them
295 if no arguments are actually popped. If the target does not have
296 "call" or "call_value" insns, then we must use the popping versions
297 even if the call has no arguments to pop. */
298 #if defined (HAVE_call) && defined (HAVE_call_value)
299 if (HAVE_call
&& HAVE_call_value
&& HAVE_call_pop
&& HAVE_call_value_pop
300 && n_popped
> 0 && ! (ecf_flags
& ECF_SP_DEPRESSED
))
302 if (HAVE_call_pop
&& HAVE_call_value_pop
)
305 rtx n_pop
= GEN_INT (n_popped
);
308 /* If this subroutine pops its own args, record that in the call insn
309 if possible, for the sake of frame pointer elimination. */
312 pat
= GEN_CALL_VALUE_POP (valreg
,
313 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
314 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
316 pat
= GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
317 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
319 emit_call_insn (pat
);
325 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
326 if ((ecf_flags
& ECF_SIBCALL
)
327 && HAVE_sibcall
&& HAVE_sibcall_value
)
330 emit_call_insn (GEN_SIBCALL_VALUE (valreg
,
331 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
332 rounded_stack_size_rtx
,
333 next_arg_reg
, NULL_RTX
));
335 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
336 rounded_stack_size_rtx
, next_arg_reg
,
337 struct_value_size_rtx
));
342 #if defined (HAVE_call) && defined (HAVE_call_value)
343 if (HAVE_call
&& HAVE_call_value
)
346 emit_call_insn (GEN_CALL_VALUE (valreg
,
347 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
348 rounded_stack_size_rtx
, next_arg_reg
,
351 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
352 rounded_stack_size_rtx
, next_arg_reg
,
353 struct_value_size_rtx
));
359 /* Find the call we just emitted. */
360 call_insn
= last_call_insn ();
362 /* Mark memory as used for "pure" function call. */
363 if (ecf_flags
& ECF_PURE
)
367 gen_rtx_USE (VOIDmode
,
368 gen_rtx_MEM (BLKmode
, gen_rtx_SCRATCH (VOIDmode
))),
371 /* Put the register usage information there. */
372 add_function_usage_to (call_insn
, call_fusage
);
374 /* If this is a const call, then set the insn's unchanging bit. */
375 if (ecf_flags
& (ECF_CONST
| ECF_PURE
))
376 CONST_OR_PURE_CALL_P (call_insn
) = 1;
378 /* If this call can't throw, attach a REG_EH_REGION reg note to that
380 if (ecf_flags
& ECF_NOTHROW
)
381 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_EH_REGION
, const0_rtx
,
382 REG_NOTES (call_insn
));
385 int rn
= lookup_stmt_eh_region (fntree
);
387 /* If rn < 0, then either (1) tree-ssa not used or (2) doesn't
388 throw, which we already took care of. */
390 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_EH_REGION
, GEN_INT (rn
),
391 REG_NOTES (call_insn
));
392 note_current_region_may_contain_throw ();
395 if (ecf_flags
& ECF_NORETURN
)
396 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_NORETURN
, const0_rtx
,
397 REG_NOTES (call_insn
));
399 if (ecf_flags
& ECF_RETURNS_TWICE
)
401 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_SETJMP
, const0_rtx
,
402 REG_NOTES (call_insn
));
403 current_function_calls_setjmp
= 1;
406 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
408 /* Restore this now, so that we do defer pops for this call's args
409 if the context of the call as a whole permits. */
410 inhibit_defer_pop
= old_inhibit_defer_pop
;
415 CALL_INSN_FUNCTION_USAGE (call_insn
)
416 = gen_rtx_EXPR_LIST (VOIDmode
,
417 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
418 CALL_INSN_FUNCTION_USAGE (call_insn
));
419 rounded_stack_size
-= n_popped
;
420 rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
421 stack_pointer_delta
-= n_popped
;
424 if (!ACCUMULATE_OUTGOING_ARGS
)
426 /* If returning from the subroutine does not automatically pop the args,
427 we need an instruction to pop them sooner or later.
428 Perhaps do it now; perhaps just record how much space to pop later.
430 If returning from the subroutine does pop the args, indicate that the
431 stack pointer will be changed. */
433 if (rounded_stack_size
!= 0)
435 if (ecf_flags
& (ECF_SP_DEPRESSED
| ECF_NORETURN
))
436 /* Just pretend we did the pop. */
437 stack_pointer_delta
-= rounded_stack_size
;
438 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
439 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
440 pending_stack_adjust
+= rounded_stack_size
;
442 adjust_stack (rounded_stack_size_rtx
);
445 /* When we accumulate outgoing args, we must avoid any stack manipulations.
446 Restore the stack pointer to its original value now. Usually
447 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
448 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
449 popping variants of functions exist as well.
451 ??? We may optimize similar to defer_pop above, but it is
452 probably not worthwhile.
454 ??? It will be worthwhile to enable combine_stack_adjustments even for
457 anti_adjust_stack (GEN_INT (n_popped
));
460 /* Determine if the function identified by NAME and FNDECL is one with
461 special properties we wish to know about.
463 For example, if the function might return more than one time (setjmp), then
464 set RETURNS_TWICE to a nonzero value.
466 Similarly set NORETURN if the function is in the longjmp family.
468 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
469 space from the stack such as alloca. */
472 special_function_p (tree fndecl
, int flags
)
474 if (fndecl
&& DECL_NAME (fndecl
)
475 && IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) <= 17
476 /* Exclude functions not at the file scope, or not `extern',
477 since they are not the magic functions we would otherwise
479 FIXME: this should be handled with attributes, not with this
480 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
481 because you can declare fork() inside a function if you
483 && (DECL_CONTEXT (fndecl
) == NULL_TREE
484 || TREE_CODE (DECL_CONTEXT (fndecl
)) == TRANSLATION_UNIT_DECL
)
485 && TREE_PUBLIC (fndecl
))
487 const char *name
= IDENTIFIER_POINTER (DECL_NAME (fndecl
));
488 const char *tname
= name
;
490 /* We assume that alloca will always be called by name. It
491 makes no sense to pass it as a pointer-to-function to
492 anything that does not understand its behavior. */
493 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 6
495 && ! strcmp (name
, "alloca"))
496 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 16
498 && ! strcmp (name
, "__builtin_alloca"))))
499 flags
|= ECF_MAY_BE_ALLOCA
;
501 /* Disregard prefix _, __ or __x. */
504 if (name
[1] == '_' && name
[2] == 'x')
506 else if (name
[1] == '_')
515 && (! strcmp (tname
, "setjmp")
516 || ! strcmp (tname
, "setjmp_syscall")))
518 && ! strcmp (tname
, "sigsetjmp"))
520 && ! strcmp (tname
, "savectx")))
521 flags
|= ECF_RETURNS_TWICE
;
524 && ! strcmp (tname
, "siglongjmp"))
525 flags
|= ECF_NORETURN
;
527 else if ((tname
[0] == 'q' && tname
[1] == 's'
528 && ! strcmp (tname
, "qsetjmp"))
529 || (tname
[0] == 'v' && tname
[1] == 'f'
530 && ! strcmp (tname
, "vfork"))
531 || (tname
[0] == 'g' && tname
[1] == 'e'
532 && !strcmp (tname
, "getcontext")))
533 flags
|= ECF_RETURNS_TWICE
;
535 else if (tname
[0] == 'l' && tname
[1] == 'o'
536 && ! strcmp (tname
, "longjmp"))
537 flags
|= ECF_NORETURN
;
543 /* Return nonzero when FNDECL represents a call to setjmp. */
546 setjmp_call_p (tree fndecl
)
548 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
551 /* Return true when exp contains alloca call. */
553 alloca_call_p (tree exp
)
555 if (TREE_CODE (exp
) == CALL_EXPR
556 && TREE_CODE (CALL_EXPR_FN (exp
)) == ADDR_EXPR
557 && (TREE_CODE (TREE_OPERAND (CALL_EXPR_FN (exp
), 0)) == FUNCTION_DECL
)
558 && (special_function_p (TREE_OPERAND (CALL_EXPR_FN (exp
), 0), 0)
559 & ECF_MAY_BE_ALLOCA
))
564 /* Detect flags (function attributes) from the function decl or type node. */
567 flags_from_decl_or_type (tree exp
)
574 type
= TREE_TYPE (exp
);
576 /* The function exp may have the `malloc' attribute. */
577 if (DECL_IS_MALLOC (exp
))
580 /* The function exp may have the `returns_twice' attribute. */
581 if (DECL_IS_RETURNS_TWICE (exp
))
582 flags
|= ECF_RETURNS_TWICE
;
584 /* The function exp may have the `pure' attribute. */
585 if (DECL_IS_PURE (exp
))
588 if (DECL_IS_NOVOPS (exp
))
591 if (TREE_NOTHROW (exp
))
592 flags
|= ECF_NOTHROW
;
594 if (TREE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
597 flags
= special_function_p (exp
, flags
);
599 else if (TYPE_P (exp
) && TYPE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
602 if (TREE_THIS_VOLATILE (exp
))
603 flags
|= ECF_NORETURN
;
605 /* Mark if the function returns with the stack pointer depressed. We
606 cannot consider it pure or constant in that case. */
607 if (TREE_CODE (type
) == FUNCTION_TYPE
&& TYPE_RETURNS_STACK_DEPRESSED (type
))
609 flags
|= ECF_SP_DEPRESSED
;
610 flags
&= ~(ECF_PURE
| ECF_CONST
);
616 /* Detect flags from a CALL_EXPR. */
619 call_expr_flags (tree t
)
622 tree decl
= get_callee_fndecl (t
);
625 flags
= flags_from_decl_or_type (decl
);
628 t
= TREE_TYPE (CALL_EXPR_FN (t
));
629 if (t
&& TREE_CODE (t
) == POINTER_TYPE
)
630 flags
= flags_from_decl_or_type (TREE_TYPE (t
));
638 /* Precompute all register parameters as described by ARGS, storing values
639 into fields within the ARGS array.
641 NUM_ACTUALS indicates the total number elements in the ARGS array.
643 Set REG_PARM_SEEN if we encounter a register parameter. */
646 precompute_register_parameters (int num_actuals
, struct arg_data
*args
,
653 for (i
= 0; i
< num_actuals
; i
++)
654 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
658 if (args
[i
].value
== 0)
661 args
[i
].value
= expand_normal (args
[i
].tree_value
);
662 preserve_temp_slots (args
[i
].value
);
666 /* If the value is a non-legitimate constant, force it into a
667 pseudo now. TLS symbols sometimes need a call to resolve. */
668 if (CONSTANT_P (args
[i
].value
)
669 && !LEGITIMATE_CONSTANT_P (args
[i
].value
))
670 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
672 /* If we are to promote the function arg to a wider mode,
675 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
677 = convert_modes (args
[i
].mode
,
678 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
679 args
[i
].value
, args
[i
].unsignedp
);
681 /* If we're going to have to load the value by parts, pull the
682 parts into pseudos. The part extraction process can involve
683 non-trivial computation. */
684 if (GET_CODE (args
[i
].reg
) == PARALLEL
)
686 tree type
= TREE_TYPE (args
[i
].tree_value
);
687 args
[i
].parallel_value
688 = emit_group_load_into_temps (args
[i
].reg
, args
[i
].value
,
689 type
, int_size_in_bytes (type
));
692 /* If the value is expensive, and we are inside an appropriately
693 short loop, put the value into a pseudo and then put the pseudo
696 For small register classes, also do this if this call uses
697 register parameters. This is to avoid reload conflicts while
698 loading the parameters registers. */
700 else if ((! (REG_P (args
[i
].value
)
701 || (GET_CODE (args
[i
].value
) == SUBREG
702 && REG_P (SUBREG_REG (args
[i
].value
)))))
703 && args
[i
].mode
!= BLKmode
704 && rtx_cost (args
[i
].value
, SET
) > COSTS_N_INSNS (1)
705 && ((SMALL_REGISTER_CLASSES
&& *reg_parm_seen
)
707 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
711 #ifdef REG_PARM_STACK_SPACE
713 /* The argument list is the property of the called routine and it
714 may clobber it. If the fixed area has been used for previous
715 parameters, we must save and restore it. */
718 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
723 /* Compute the boundary of the area that needs to be saved, if any. */
724 high
= reg_parm_stack_space
;
725 #ifdef ARGS_GROW_DOWNWARD
728 if (high
> highest_outgoing_arg_in_use
)
729 high
= highest_outgoing_arg_in_use
;
731 for (low
= 0; low
< high
; low
++)
732 if (stack_usage_map
[low
] != 0)
735 enum machine_mode save_mode
;
740 while (stack_usage_map
[--high
] == 0)
744 *high_to_save
= high
;
746 num_to_save
= high
- low
+ 1;
747 save_mode
= mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
749 /* If we don't have the required alignment, must do this
751 if ((low
& (MIN (GET_MODE_SIZE (save_mode
),
752 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
755 #ifdef ARGS_GROW_DOWNWARD
760 stack_area
= gen_rtx_MEM (save_mode
,
761 memory_address (save_mode
,
762 plus_constant (argblock
,
765 set_mem_align (stack_area
, PARM_BOUNDARY
);
766 if (save_mode
== BLKmode
)
768 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
769 emit_block_move (validize_mem (save_area
), stack_area
,
770 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
774 save_area
= gen_reg_rtx (save_mode
);
775 emit_move_insn (save_area
, stack_area
);
785 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
787 enum machine_mode save_mode
= GET_MODE (save_area
);
791 #ifdef ARGS_GROW_DOWNWARD
792 delta
= -high_to_save
;
796 stack_area
= gen_rtx_MEM (save_mode
,
797 memory_address (save_mode
,
798 plus_constant (argblock
, delta
)));
799 set_mem_align (stack_area
, PARM_BOUNDARY
);
801 if (save_mode
!= BLKmode
)
802 emit_move_insn (stack_area
, save_area
);
804 emit_block_move (stack_area
, validize_mem (save_area
),
805 GEN_INT (high_to_save
- low_to_save
+ 1),
808 #endif /* REG_PARM_STACK_SPACE */
810 /* If any elements in ARGS refer to parameters that are to be passed in
811 registers, but not in memory, and whose alignment does not permit a
812 direct copy into registers. Copy the values into a group of pseudos
813 which we will later copy into the appropriate hard registers.
815 Pseudos for each unaligned argument will be stored into the array
816 args[argnum].aligned_regs. The caller is responsible for deallocating
817 the aligned_regs array if it is nonzero. */
820 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
824 for (i
= 0; i
< num_actuals
; i
++)
825 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
826 && args
[i
].mode
== BLKmode
827 && (TYPE_ALIGN (TREE_TYPE (args
[i
].tree_value
))
828 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
830 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
831 int endian_correction
= 0;
835 gcc_assert (args
[i
].partial
% UNITS_PER_WORD
== 0);
836 args
[i
].n_aligned_regs
= args
[i
].partial
/ UNITS_PER_WORD
;
840 args
[i
].n_aligned_regs
841 = (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
844 args
[i
].aligned_regs
= XNEWVEC (rtx
, args
[i
].n_aligned_regs
);
846 /* Structures smaller than a word are normally aligned to the
847 least significant byte. On a BYTES_BIG_ENDIAN machine,
848 this means we must skip the empty high order bytes when
849 calculating the bit offset. */
850 if (bytes
< UNITS_PER_WORD
851 #ifdef BLOCK_REG_PADDING
852 && (BLOCK_REG_PADDING (args
[i
].mode
,
853 TREE_TYPE (args
[i
].tree_value
), 1)
859 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
861 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
863 rtx reg
= gen_reg_rtx (word_mode
);
864 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
865 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
867 args
[i
].aligned_regs
[j
] = reg
;
868 word
= extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
869 word_mode
, word_mode
);
871 /* There is no need to restrict this code to loading items
872 in TYPE_ALIGN sized hunks. The bitfield instructions can
873 load up entire word sized registers efficiently.
875 ??? This may not be needed anymore.
876 We use to emit a clobber here but that doesn't let later
877 passes optimize the instructions we emit. By storing 0 into
878 the register later passes know the first AND to zero out the
879 bitfield being set in the register is unnecessary. The store
880 of 0 will be deleted as will at least the first AND. */
882 emit_move_insn (reg
, const0_rtx
);
884 bytes
-= bitsize
/ BITS_PER_UNIT
;
885 store_bit_field (reg
, bitsize
, endian_correction
, word_mode
,
891 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
894 NUM_ACTUALS is the total number of parameters.
896 N_NAMED_ARGS is the total number of named arguments.
898 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
901 FNDECL is the tree code for the target of this call (if known)
903 ARGS_SO_FAR holds state needed by the target to know where to place
906 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
907 for arguments which are passed in registers.
909 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
910 and may be modified by this routine.
912 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
913 flags which may may be modified by this routine.
915 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
916 that requires allocation of stack space.
918 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
919 the thunked-to function. */
922 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
923 struct arg_data
*args
,
924 struct args_size
*args_size
,
925 int n_named_args ATTRIBUTE_UNUSED
,
926 tree exp
, tree struct_value_addr_value
,
928 CUMULATIVE_ARGS
*args_so_far
,
929 int reg_parm_stack_space
,
930 rtx
*old_stack_level
, int *old_pending_adj
,
931 int *must_preallocate
, int *ecf_flags
,
932 bool *may_tailcall
, bool call_from_thunk_p
)
934 /* 1 if scanning parms front to back, -1 if scanning back to front. */
937 /* Count arg position in order args appear. */
942 args_size
->constant
= 0;
945 /* In this loop, we consider args in the order they are written.
946 We fill up ARGS from the front or from the back if necessary
947 so that in any case the first arg to be pushed ends up at the front. */
949 if (PUSH_ARGS_REVERSED
)
951 i
= num_actuals
- 1, inc
= -1;
952 /* In this case, must reverse order of args
953 so that we compute and push the last arg first. */
960 /* First fill in the actual arguments in the ARGS array, splitting
961 complex arguments if necessary. */
964 call_expr_arg_iterator iter
;
967 if (struct_value_addr_value
)
969 args
[j
].tree_value
= struct_value_addr_value
;
972 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
974 tree argtype
= TREE_TYPE (arg
);
975 if (targetm
.calls
.split_complex_arg
977 && TREE_CODE (argtype
) == COMPLEX_TYPE
978 && targetm
.calls
.split_complex_arg (argtype
))
980 tree subtype
= TREE_TYPE (argtype
);
981 arg
= save_expr (arg
);
982 args
[j
].tree_value
= build1 (REALPART_EXPR
, subtype
, arg
);
984 args
[j
].tree_value
= build1 (IMAGPART_EXPR
, subtype
, arg
);
987 args
[j
].tree_value
= arg
;
992 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
993 for (argpos
= 0; argpos
< num_actuals
; i
+= inc
, argpos
++)
995 tree type
= TREE_TYPE (args
[i
].tree_value
);
997 enum machine_mode mode
;
999 /* Replace erroneous argument with constant zero. */
1000 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1001 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1003 /* If TYPE is a transparent union, pass things the way we would
1004 pass the first field of the union. We have already verified that
1005 the modes are the same. */
1006 if (TREE_CODE (type
) == UNION_TYPE
&& TYPE_TRANSPARENT_UNION (type
))
1007 type
= TREE_TYPE (TYPE_FIELDS (type
));
1009 /* Decide where to pass this arg.
1011 args[i].reg is nonzero if all or part is passed in registers.
1013 args[i].partial is nonzero if part but not all is passed in registers,
1014 and the exact value says how many bytes are passed in registers.
1016 args[i].pass_on_stack is nonzero if the argument must at least be
1017 computed on the stack. It may then be loaded back into registers
1018 if args[i].reg is nonzero.
1020 These decisions are driven by the FUNCTION_... macros and must agree
1021 with those made by function.c. */
1023 /* See if this argument should be passed by invisible reference. */
1024 if (pass_by_reference (args_so_far
, TYPE_MODE (type
),
1025 type
, argpos
< n_named_args
))
1031 = reference_callee_copied (args_so_far
, TYPE_MODE (type
),
1032 type
, argpos
< n_named_args
);
1034 /* If we're compiling a thunk, pass through invisible references
1035 instead of making a copy. */
1036 if (call_from_thunk_p
1038 && !TREE_ADDRESSABLE (type
)
1039 && (base
= get_base_address (args
[i
].tree_value
))
1040 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
)))))
1042 /* We can't use sibcalls if a callee-copied argument is
1043 stored in the current function's frame. */
1044 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
1045 *may_tailcall
= false;
1047 args
[i
].tree_value
= build_fold_addr_expr (args
[i
].tree_value
);
1048 type
= TREE_TYPE (args
[i
].tree_value
);
1050 *ecf_flags
&= ~(ECF_CONST
| ECF_LIBCALL_BLOCK
);
1054 /* We make a copy of the object and pass the address to the
1055 function being called. */
1058 if (!COMPLETE_TYPE_P (type
)
1059 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1060 || (flag_stack_check
&& ! STACK_CHECK_BUILTIN
1061 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type
),
1062 STACK_CHECK_MAX_VAR_SIZE
))))
1064 /* This is a variable-sized object. Make space on the stack
1066 rtx size_rtx
= expr_size (args
[i
].tree_value
);
1068 if (*old_stack_level
== 0)
1070 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1071 *old_pending_adj
= pending_stack_adjust
;
1072 pending_stack_adjust
= 0;
1075 copy
= gen_rtx_MEM (BLKmode
,
1076 allocate_dynamic_stack_space
1077 (size_rtx
, NULL_RTX
, TYPE_ALIGN (type
)));
1078 set_mem_attributes (copy
, type
, 1);
1081 copy
= assign_temp (type
, 0, 1, 0);
1083 store_expr (args
[i
].tree_value
, copy
, 0);
1086 *ecf_flags
&= ~(ECF_CONST
| ECF_LIBCALL_BLOCK
);
1088 *ecf_flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
1091 = build_fold_addr_expr (make_tree (type
, copy
));
1092 type
= TREE_TYPE (args
[i
].tree_value
);
1093 *may_tailcall
= false;
1097 mode
= TYPE_MODE (type
);
1098 unsignedp
= TYPE_UNSIGNED (type
);
1100 if (targetm
.calls
.promote_function_args (fndecl
? TREE_TYPE (fndecl
) : 0))
1101 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
1103 args
[i
].unsignedp
= unsignedp
;
1104 args
[i
].mode
= mode
;
1106 args
[i
].reg
= FUNCTION_ARG (*args_so_far
, mode
, type
,
1107 argpos
< n_named_args
);
1108 #ifdef FUNCTION_INCOMING_ARG
1109 /* If this is a sibling call and the machine has register windows, the
1110 register window has to be unwinded before calling the routine, so
1111 arguments have to go into the incoming registers. */
1112 args
[i
].tail_call_reg
= FUNCTION_INCOMING_ARG (*args_so_far
, mode
, type
,
1113 argpos
< n_named_args
);
1115 args
[i
].tail_call_reg
= args
[i
].reg
;
1120 = targetm
.calls
.arg_partial_bytes (args_so_far
, mode
, type
,
1121 argpos
< n_named_args
);
1123 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (mode
, type
);
1125 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1126 it means that we are to pass this arg in the register(s) designated
1127 by the PARALLEL, but also to pass it in the stack. */
1128 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1129 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1130 args
[i
].pass_on_stack
= 1;
1132 /* If this is an addressable type, we must preallocate the stack
1133 since we must evaluate the object into its final location.
1135 If this is to be passed in both registers and the stack, it is simpler
1137 if (TREE_ADDRESSABLE (type
)
1138 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1139 *must_preallocate
= 1;
1141 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1142 we cannot consider this function call constant. */
1143 if (TREE_ADDRESSABLE (type
))
1144 *ecf_flags
&= ~ECF_LIBCALL_BLOCK
;
1146 /* Compute the stack-size of this argument. */
1147 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1148 || reg_parm_stack_space
> 0
1149 || args
[i
].pass_on_stack
)
1150 locate_and_pad_parm (mode
, type
,
1151 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1156 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
1157 fndecl
, args_size
, &args
[i
].locate
);
1158 #ifdef BLOCK_REG_PADDING
1160 /* The argument is passed entirely in registers. See at which
1161 end it should be padded. */
1162 args
[i
].locate
.where_pad
=
1163 BLOCK_REG_PADDING (mode
, type
,
1164 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
1167 /* Update ARGS_SIZE, the total stack space for args so far. */
1169 args_size
->constant
+= args
[i
].locate
.size
.constant
;
1170 if (args
[i
].locate
.size
.var
)
1171 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
1173 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1174 have been used, etc. */
1176 FUNCTION_ARG_ADVANCE (*args_so_far
, TYPE_MODE (type
), type
,
1177 argpos
< n_named_args
);
1181 /* Update ARGS_SIZE to contain the total size for the argument block.
1182 Return the original constant component of the argument block's size.
1184 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1185 for arguments passed in registers. */
1188 compute_argument_block_size (int reg_parm_stack_space
,
1189 struct args_size
*args_size
,
1190 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
1192 int unadjusted_args_size
= args_size
->constant
;
1194 /* For accumulate outgoing args mode we don't need to align, since the frame
1195 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1196 backends from generating misaligned frame sizes. */
1197 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1198 preferred_stack_boundary
= STACK_BOUNDARY
;
1200 /* Compute the actual size of the argument block required. The variable
1201 and constant sizes must be combined, the size may have to be rounded,
1202 and there may be a minimum required size. */
1206 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1207 args_size
->constant
= 0;
1209 preferred_stack_boundary
/= BITS_PER_UNIT
;
1210 if (preferred_stack_boundary
> 1)
1212 /* We don't handle this case yet. To handle it correctly we have
1213 to add the delta, round and subtract the delta.
1214 Currently no machine description requires this support. */
1215 gcc_assert (!(stack_pointer_delta
& (preferred_stack_boundary
- 1)));
1216 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1219 if (reg_parm_stack_space
> 0)
1222 = size_binop (MAX_EXPR
, args_size
->var
,
1223 ssize_int (reg_parm_stack_space
));
1225 /* The area corresponding to register parameters is not to count in
1226 the size of the block we need. So make the adjustment. */
1227 if (!OUTGOING_REG_PARM_STACK_SPACE
)
1229 = size_binop (MINUS_EXPR
, args_size
->var
,
1230 ssize_int (reg_parm_stack_space
));
1235 preferred_stack_boundary
/= BITS_PER_UNIT
;
1236 if (preferred_stack_boundary
< 1)
1237 preferred_stack_boundary
= 1;
1238 args_size
->constant
= (((args_size
->constant
1239 + stack_pointer_delta
1240 + preferred_stack_boundary
- 1)
1241 / preferred_stack_boundary
1242 * preferred_stack_boundary
)
1243 - stack_pointer_delta
);
1245 args_size
->constant
= MAX (args_size
->constant
,
1246 reg_parm_stack_space
);
1248 if (!OUTGOING_REG_PARM_STACK_SPACE
)
1249 args_size
->constant
-= reg_parm_stack_space
;
1251 return unadjusted_args_size
;
1254 /* Precompute parameters as needed for a function call.
1256 FLAGS is mask of ECF_* constants.
1258 NUM_ACTUALS is the number of arguments.
1260 ARGS is an array containing information for each argument; this
1261 routine fills in the INITIAL_VALUE and VALUE fields for each
1262 precomputed argument. */
1265 precompute_arguments (int flags
, int num_actuals
, struct arg_data
*args
)
1269 /* If this is a libcall, then precompute all arguments so that we do not
1270 get extraneous instructions emitted as part of the libcall sequence. */
1271 if ((flags
& ECF_LIBCALL_BLOCK
) == 0)
1274 for (i
= 0; i
< num_actuals
; i
++)
1276 enum machine_mode mode
;
1278 /* If this is an addressable type, we cannot pre-evaluate it. */
1279 gcc_assert (!TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
)));
1281 args
[i
].initial_value
= args
[i
].value
1282 = expand_normal (args
[i
].tree_value
);
1284 mode
= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
));
1285 if (mode
!= args
[i
].mode
)
1288 = convert_modes (args
[i
].mode
, mode
,
1289 args
[i
].value
, args
[i
].unsignedp
);
1290 #if defined(PROMOTE_FUNCTION_MODE) && !defined(PROMOTE_MODE)
1291 /* CSE will replace this only if it contains args[i].value
1292 pseudo, so convert it down to the declared mode using
1294 if (REG_P (args
[i
].value
)
1295 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
)
1297 args
[i
].initial_value
1298 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1299 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1300 SUBREG_PROMOTED_UNSIGNED_SET (args
[i
].initial_value
,
1308 /* Given the current state of MUST_PREALLOCATE and information about
1309 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1310 compute and return the final value for MUST_PREALLOCATE. */
1313 finalize_must_preallocate (int must_preallocate
, int num_actuals
,
1314 struct arg_data
*args
, struct args_size
*args_size
)
1316 /* See if we have or want to preallocate stack space.
1318 If we would have to push a partially-in-regs parm
1319 before other stack parms, preallocate stack space instead.
1321 If the size of some parm is not a multiple of the required stack
1322 alignment, we must preallocate.
1324 If the total size of arguments that would otherwise create a copy in
1325 a temporary (such as a CALL) is more than half the total argument list
1326 size, preallocation is faster.
1328 Another reason to preallocate is if we have a machine (like the m88k)
1329 where stack alignment is required to be maintained between every
1330 pair of insns, not just when the call is made. However, we assume here
1331 that such machines either do not have push insns (and hence preallocation
1332 would occur anyway) or the problem is taken care of with
1335 if (! must_preallocate
)
1337 int partial_seen
= 0;
1338 int copy_to_evaluate_size
= 0;
1341 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1343 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1345 else if (partial_seen
&& args
[i
].reg
== 0)
1346 must_preallocate
= 1;
1348 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1349 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1350 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1351 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1352 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1353 copy_to_evaluate_size
1354 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1357 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1358 && args_size
->constant
> 0)
1359 must_preallocate
= 1;
1361 return must_preallocate
;
1364 /* If we preallocated stack space, compute the address of each argument
1365 and store it into the ARGS array.
1367 We need not ensure it is a valid memory address here; it will be
1368 validized when it is used.
1370 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1373 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
1377 rtx arg_reg
= argblock
;
1378 int i
, arg_offset
= 0;
1380 if (GET_CODE (argblock
) == PLUS
)
1381 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1383 for (i
= 0; i
< num_actuals
; i
++)
1385 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
1386 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
1388 unsigned int align
, boundary
;
1389 unsigned int units_on_stack
= 0;
1390 enum machine_mode partial_mode
= VOIDmode
;
1392 /* Skip this parm if it will not be passed on the stack. */
1393 if (! args
[i
].pass_on_stack
1395 && args
[i
].partial
== 0)
1398 if (GET_CODE (offset
) == CONST_INT
)
1399 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1401 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1403 addr
= plus_constant (addr
, arg_offset
);
1405 if (args
[i
].partial
!= 0)
1407 /* Only part of the parameter is being passed on the stack.
1408 Generate a simple memory reference of the correct size. */
1409 units_on_stack
= args
[i
].locate
.size
.constant
;
1410 partial_mode
= mode_for_size (units_on_stack
* BITS_PER_UNIT
,
1412 args
[i
].stack
= gen_rtx_MEM (partial_mode
, addr
);
1413 set_mem_size (args
[i
].stack
, GEN_INT (units_on_stack
));
1417 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1418 set_mem_attributes (args
[i
].stack
,
1419 TREE_TYPE (args
[i
].tree_value
), 1);
1421 align
= BITS_PER_UNIT
;
1422 boundary
= args
[i
].locate
.boundary
;
1423 if (args
[i
].locate
.where_pad
!= downward
)
1425 else if (GET_CODE (offset
) == CONST_INT
)
1427 align
= INTVAL (offset
) * BITS_PER_UNIT
| boundary
;
1428 align
= align
& -align
;
1430 set_mem_align (args
[i
].stack
, align
);
1432 if (GET_CODE (slot_offset
) == CONST_INT
)
1433 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1435 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1437 addr
= plus_constant (addr
, arg_offset
);
1439 if (args
[i
].partial
!= 0)
1441 /* Only part of the parameter is being passed on the stack.
1442 Generate a simple memory reference of the correct size.
1444 args
[i
].stack_slot
= gen_rtx_MEM (partial_mode
, addr
);
1445 set_mem_size (args
[i
].stack_slot
, GEN_INT (units_on_stack
));
1449 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1450 set_mem_attributes (args
[i
].stack_slot
,
1451 TREE_TYPE (args
[i
].tree_value
), 1);
1453 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
1455 /* Function incoming arguments may overlap with sibling call
1456 outgoing arguments and we cannot allow reordering of reads
1457 from function arguments with stores to outgoing arguments
1458 of sibling calls. */
1459 set_mem_alias_set (args
[i
].stack
, 0);
1460 set_mem_alias_set (args
[i
].stack_slot
, 0);
1465 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1466 in a call instruction.
1468 FNDECL is the tree node for the target function. For an indirect call
1469 FNDECL will be NULL_TREE.
1471 ADDR is the operand 0 of CALL_EXPR for this call. */
1474 rtx_for_function_call (tree fndecl
, tree addr
)
1478 /* Get the function to call, in the form of RTL. */
1481 /* If this is the first use of the function, see if we need to
1482 make an external definition for it. */
1483 if (! TREE_USED (fndecl
))
1485 assemble_external (fndecl
);
1486 TREE_USED (fndecl
) = 1;
1489 /* Get a SYMBOL_REF rtx for the function address. */
1490 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1493 /* Generate an rtx (probably a pseudo-register) for the address. */
1496 funexp
= expand_normal (addr
);
1497 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1502 /* Return true if and only if SIZE storage units (usually bytes)
1503 starting from address ADDR overlap with already clobbered argument
1504 area. This function is used to determine if we should give up a
1508 mem_overlaps_already_clobbered_arg_p (rtx addr
, unsigned HOST_WIDE_INT size
)
1512 if (addr
== current_function_internal_arg_pointer
)
1514 else if (GET_CODE (addr
) == PLUS
1515 && XEXP (addr
, 0) == current_function_internal_arg_pointer
1516 && GET_CODE (XEXP (addr
, 1)) == CONST_INT
)
1517 i
= INTVAL (XEXP (addr
, 1));
1518 /* Return true for arg pointer based indexed addressing. */
1519 else if (GET_CODE (addr
) == PLUS
1520 && (XEXP (addr
, 0) == current_function_internal_arg_pointer
1521 || XEXP (addr
, 1) == current_function_internal_arg_pointer
))
1526 #ifdef ARGS_GROW_DOWNWARD
1531 unsigned HOST_WIDE_INT k
;
1533 for (k
= 0; k
< size
; k
++)
1534 if (i
+ k
< stored_args_map
->n_bits
1535 && TEST_BIT (stored_args_map
, i
+ k
))
1542 /* Do the register loads required for any wholly-register parms or any
1543 parms which are passed both on the stack and in a register. Their
1544 expressions were already evaluated.
1546 Mark all register-parms as living through the call, putting these USE
1547 insns in the CALL_INSN_FUNCTION_USAGE field.
1549 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1550 checking, setting *SIBCALL_FAILURE if appropriate. */
1553 load_register_parameters (struct arg_data
*args
, int num_actuals
,
1554 rtx
*call_fusage
, int flags
, int is_sibcall
,
1555 int *sibcall_failure
)
1559 for (i
= 0; i
< num_actuals
; i
++)
1561 rtx reg
= ((flags
& ECF_SIBCALL
)
1562 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1565 int partial
= args
[i
].partial
;
1568 rtx before_arg
= get_last_insn ();
1569 /* Set non-negative if we must move a word at a time, even if
1570 just one word (e.g, partial == 4 && mode == DFmode). Set
1571 to -1 if we just use a normal move insn. This value can be
1572 zero if the argument is a zero size structure. */
1574 if (GET_CODE (reg
) == PARALLEL
)
1578 gcc_assert (partial
% UNITS_PER_WORD
== 0);
1579 nregs
= partial
/ UNITS_PER_WORD
;
1581 else if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
)
1583 size
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1584 nregs
= (size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1587 size
= GET_MODE_SIZE (args
[i
].mode
);
1589 /* Handle calls that pass values in multiple non-contiguous
1590 locations. The Irix 6 ABI has examples of this. */
1592 if (GET_CODE (reg
) == PARALLEL
)
1593 emit_group_move (reg
, args
[i
].parallel_value
);
1595 /* If simple case, just do move. If normal partial, store_one_arg
1596 has already loaded the register for us. In all other cases,
1597 load the register(s) from memory. */
1599 else if (nregs
== -1)
1601 emit_move_insn (reg
, args
[i
].value
);
1602 #ifdef BLOCK_REG_PADDING
1603 /* Handle case where we have a value that needs shifting
1604 up to the msb. eg. a QImode value and we're padding
1605 upward on a BYTES_BIG_ENDIAN machine. */
1606 if (size
< UNITS_PER_WORD
1607 && (args
[i
].locate
.where_pad
1608 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
1611 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1613 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1614 report the whole reg as used. Strictly speaking, the
1615 call only uses SIZE bytes at the msb end, but it doesn't
1616 seem worth generating rtl to say that. */
1617 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
1618 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
1619 build_int_cst (NULL_TREE
, shift
),
1622 emit_move_insn (reg
, x
);
1627 /* If we have pre-computed the values to put in the registers in
1628 the case of non-aligned structures, copy them in now. */
1630 else if (args
[i
].n_aligned_regs
!= 0)
1631 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1632 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1633 args
[i
].aligned_regs
[j
]);
1635 else if (partial
== 0 || args
[i
].pass_on_stack
)
1637 rtx mem
= validize_mem (args
[i
].value
);
1639 /* Check for overlap with already clobbered argument area. */
1641 && mem_overlaps_already_clobbered_arg_p (XEXP (args
[i
].value
, 0),
1643 *sibcall_failure
= 1;
1645 /* Handle a BLKmode that needs shifting. */
1646 if (nregs
== 1 && size
< UNITS_PER_WORD
1647 #ifdef BLOCK_REG_PADDING
1648 && args
[i
].locate
.where_pad
== downward
1654 rtx tem
= operand_subword_force (mem
, 0, args
[i
].mode
);
1655 rtx ri
= gen_rtx_REG (word_mode
, REGNO (reg
));
1656 rtx x
= gen_reg_rtx (word_mode
);
1657 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1658 enum tree_code dir
= BYTES_BIG_ENDIAN
? RSHIFT_EXPR
1661 emit_move_insn (x
, tem
);
1662 x
= expand_shift (dir
, word_mode
, x
,
1663 build_int_cst (NULL_TREE
, shift
),
1666 emit_move_insn (ri
, x
);
1669 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
1672 /* When a parameter is a block, and perhaps in other cases, it is
1673 possible that it did a load from an argument slot that was
1674 already clobbered. */
1676 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
1677 *sibcall_failure
= 1;
1679 /* Handle calls that pass values in multiple non-contiguous
1680 locations. The Irix 6 ABI has examples of this. */
1681 if (GET_CODE (reg
) == PARALLEL
)
1682 use_group_regs (call_fusage
, reg
);
1683 else if (nregs
== -1)
1684 use_reg (call_fusage
, reg
);
1686 use_regs (call_fusage
, REGNO (reg
), nregs
);
1691 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1692 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1693 bytes, then we would need to push some additional bytes to pad the
1694 arguments. So, we compute an adjust to the stack pointer for an
1695 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1696 bytes. Then, when the arguments are pushed the stack will be perfectly
1697 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1698 be popped after the call. Returns the adjustment. */
1701 combine_pending_stack_adjustment_and_call (int unadjusted_args_size
,
1702 struct args_size
*args_size
,
1703 unsigned int preferred_unit_stack_boundary
)
1705 /* The number of bytes to pop so that the stack will be
1706 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1707 HOST_WIDE_INT adjustment
;
1708 /* The alignment of the stack after the arguments are pushed, if we
1709 just pushed the arguments without adjust the stack here. */
1710 unsigned HOST_WIDE_INT unadjusted_alignment
;
1712 unadjusted_alignment
1713 = ((stack_pointer_delta
+ unadjusted_args_size
)
1714 % preferred_unit_stack_boundary
);
1716 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1717 as possible -- leaving just enough left to cancel out the
1718 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1719 PENDING_STACK_ADJUST is non-negative, and congruent to
1720 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1722 /* Begin by trying to pop all the bytes. */
1723 unadjusted_alignment
1724 = (unadjusted_alignment
1725 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1726 adjustment
= pending_stack_adjust
;
1727 /* Push enough additional bytes that the stack will be aligned
1728 after the arguments are pushed. */
1729 if (preferred_unit_stack_boundary
> 1)
1731 if (unadjusted_alignment
> 0)
1732 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1734 adjustment
+= unadjusted_alignment
;
1737 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1738 bytes after the call. The right number is the entire
1739 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1740 by the arguments in the first place. */
1742 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1747 /* Scan X expression if it does not dereference any argument slots
1748 we already clobbered by tail call arguments (as noted in stored_args_map
1750 Return nonzero if X expression dereferences such argument slots,
1754 check_sibcall_argument_overlap_1 (rtx x
)
1763 code
= GET_CODE (x
);
1766 return mem_overlaps_already_clobbered_arg_p (XEXP (x
, 0),
1767 GET_MODE_SIZE (GET_MODE (x
)));
1769 /* Scan all subexpressions. */
1770 fmt
= GET_RTX_FORMAT (code
);
1771 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
1775 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
1778 else if (*fmt
== 'E')
1780 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
1781 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
1788 /* Scan sequence after INSN if it does not dereference any argument slots
1789 we already clobbered by tail call arguments (as noted in stored_args_map
1790 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1791 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1792 should be 0). Return nonzero if sequence after INSN dereferences such argument
1793 slots, zero otherwise. */
1796 check_sibcall_argument_overlap (rtx insn
, struct arg_data
*arg
, int mark_stored_args_map
)
1800 if (insn
== NULL_RTX
)
1801 insn
= get_insns ();
1803 insn
= NEXT_INSN (insn
);
1805 for (; insn
; insn
= NEXT_INSN (insn
))
1807 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
1810 if (mark_stored_args_map
)
1812 #ifdef ARGS_GROW_DOWNWARD
1813 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
1815 low
= arg
->locate
.slot_offset
.constant
;
1818 for (high
= low
+ arg
->locate
.size
.constant
; low
< high
; low
++)
1819 SET_BIT (stored_args_map
, low
);
1821 return insn
!= NULL_RTX
;
1824 /* Given that a function returns a value of mode MODE at the most
1825 significant end of hard register VALUE, shift VALUE left or right
1826 as specified by LEFT_P. Return true if some action was needed. */
1829 shift_return_value (enum machine_mode mode
, bool left_p
, rtx value
)
1831 HOST_WIDE_INT shift
;
1833 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
1834 shift
= GET_MODE_BITSIZE (GET_MODE (value
)) - GET_MODE_BITSIZE (mode
);
1838 /* Use ashr rather than lshr for right shifts. This is for the benefit
1839 of the MIPS port, which requires SImode values to be sign-extended
1840 when stored in 64-bit registers. */
1841 if (!force_expand_binop (GET_MODE (value
), left_p
? ashl_optab
: ashr_optab
,
1842 value
, GEN_INT (shift
), value
, 1, OPTAB_WIDEN
))
1847 /* Generate all the code for a CALL_EXPR exp
1848 and return an rtx for its value.
1849 Store the value in TARGET (specified as an rtx) if convenient.
1850 If the value is stored in TARGET then TARGET is returned.
1851 If IGNORE is nonzero, then we ignore the value of the function call. */
1854 expand_call (tree exp
, rtx target
, int ignore
)
1856 /* Nonzero if we are currently expanding a call. */
1857 static int currently_expanding_call
= 0;
1859 /* RTX for the function to be called. */
1861 /* Sequence of insns to perform a normal "call". */
1862 rtx normal_call_insns
= NULL_RTX
;
1863 /* Sequence of insns to perform a tail "call". */
1864 rtx tail_call_insns
= NULL_RTX
;
1865 /* Data type of the function. */
1867 tree type_arg_types
;
1868 /* Declaration of the function being called,
1869 or 0 if the function is computed (not known by name). */
1871 /* The type of the function being called. */
1873 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
1876 /* Register in which non-BLKmode value will be returned,
1877 or 0 if no value or if value is BLKmode. */
1879 /* Address where we should return a BLKmode value;
1880 0 if value not BLKmode. */
1881 rtx structure_value_addr
= 0;
1882 /* Nonzero if that address is being passed by treating it as
1883 an extra, implicit first parameter. Otherwise,
1884 it is passed by being copied directly into struct_value_rtx. */
1885 int structure_value_addr_parm
= 0;
1886 /* Holds the value of implicit argument for the struct value. */
1887 tree structure_value_addr_value
= NULL_TREE
;
1888 /* Size of aggregate value wanted, or zero if none wanted
1889 or if we are using the non-reentrant PCC calling convention
1890 or expecting the value in registers. */
1891 HOST_WIDE_INT struct_value_size
= 0;
1892 /* Nonzero if called function returns an aggregate in memory PCC style,
1893 by returning the address of where to find it. */
1894 int pcc_struct_value
= 0;
1895 rtx struct_value
= 0;
1897 /* Number of actual parameters in this call, including struct value addr. */
1899 /* Number of named args. Args after this are anonymous ones
1900 and they must all go on the stack. */
1902 /* Number of complex actual arguments that need to be split. */
1903 int num_complex_actuals
= 0;
1905 /* Vector of information about each argument.
1906 Arguments are numbered in the order they will be pushed,
1907 not the order they are written. */
1908 struct arg_data
*args
;
1910 /* Total size in bytes of all the stack-parms scanned so far. */
1911 struct args_size args_size
;
1912 struct args_size adjusted_args_size
;
1913 /* Size of arguments before any adjustments (such as rounding). */
1914 int unadjusted_args_size
;
1915 /* Data on reg parms scanned so far. */
1916 CUMULATIVE_ARGS args_so_far
;
1917 /* Nonzero if a reg parm has been scanned. */
1919 /* Nonzero if this is an indirect function call. */
1921 /* Nonzero if we must avoid push-insns in the args for this call.
1922 If stack space is allocated for register parameters, but not by the
1923 caller, then it is preallocated in the fixed part of the stack frame.
1924 So the entire argument block must then be preallocated (i.e., we
1925 ignore PUSH_ROUNDING in that case). */
1927 int must_preallocate
= !PUSH_ARGS
;
1929 /* Size of the stack reserved for parameter registers. */
1930 int reg_parm_stack_space
= 0;
1932 /* Address of space preallocated for stack parms
1933 (on machines that lack push insns), or 0 if space not preallocated. */
1936 /* Mask of ECF_ flags. */
1938 #ifdef REG_PARM_STACK_SPACE
1939 /* Define the boundary of the register parm stack space that needs to be
1941 int low_to_save
, high_to_save
;
1942 rtx save_area
= 0; /* Place that it is saved */
1945 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
1946 char *initial_stack_usage_map
= stack_usage_map
;
1947 char *stack_usage_map_buf
= NULL
;
1949 int old_stack_allocated
;
1951 /* State variables to track stack modifications. */
1952 rtx old_stack_level
= 0;
1953 int old_stack_arg_under_construction
= 0;
1954 int old_pending_adj
= 0;
1955 int old_inhibit_defer_pop
= inhibit_defer_pop
;
1957 /* Some stack pointer alterations we make are performed via
1958 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
1959 which we then also need to save/restore along the way. */
1960 int old_stack_pointer_delta
= 0;
1963 tree p
= CALL_EXPR_FN (exp
);
1964 tree addr
= CALL_EXPR_FN (exp
);
1966 /* The alignment of the stack, in bits. */
1967 unsigned HOST_WIDE_INT preferred_stack_boundary
;
1968 /* The alignment of the stack, in bytes. */
1969 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
1970 /* The static chain value to use for this call. */
1971 rtx static_chain_value
;
1972 /* See if this is "nothrow" function call. */
1973 if (TREE_NOTHROW (exp
))
1974 flags
|= ECF_NOTHROW
;
1976 /* See if we can find a DECL-node for the actual function, and get the
1977 function attributes (flags) from the function decl or type node. */
1978 fndecl
= get_callee_fndecl (exp
);
1981 fntype
= TREE_TYPE (fndecl
);
1982 flags
|= flags_from_decl_or_type (fndecl
);
1986 fntype
= TREE_TYPE (TREE_TYPE (p
));
1987 flags
|= flags_from_decl_or_type (fntype
);
1990 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
1992 /* Warn if this value is an aggregate type,
1993 regardless of which calling convention we are using for it. */
1994 if (AGGREGATE_TYPE_P (TREE_TYPE (exp
)))
1995 warning (OPT_Waggregate_return
, "function call has aggregate value");
1997 /* If the result of a pure or const function call is ignored (or void),
1998 and none of its arguments are volatile, we can avoid expanding the
1999 call and just evaluate the arguments for side-effects. */
2000 if ((flags
& (ECF_CONST
| ECF_PURE
))
2001 && (ignore
|| target
== const0_rtx
2002 || TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
))
2004 bool volatilep
= false;
2006 call_expr_arg_iterator iter
;
2008 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2009 if (TREE_THIS_VOLATILE (arg
))
2017 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2018 expand_expr (arg
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
2023 #ifdef REG_PARM_STACK_SPACE
2024 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
2027 if (!OUTGOING_REG_PARM_STACK_SPACE
&& reg_parm_stack_space
> 0 && PUSH_ARGS
)
2028 must_preallocate
= 1;
2030 /* Set up a place to return a structure. */
2032 /* Cater to broken compilers. */
2033 if (aggregate_value_p (exp
, fndecl
))
2035 /* This call returns a big structure. */
2036 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
2038 #ifdef PCC_STATIC_STRUCT_RETURN
2040 pcc_struct_value
= 1;
2042 #else /* not PCC_STATIC_STRUCT_RETURN */
2044 struct_value_size
= int_size_in_bytes (TREE_TYPE (exp
));
2046 if (target
&& MEM_P (target
) && CALL_EXPR_RETURN_SLOT_OPT (exp
))
2047 structure_value_addr
= XEXP (target
, 0);
2050 /* For variable-sized objects, we must be called with a target
2051 specified. If we were to allocate space on the stack here,
2052 we would have no way of knowing when to free it. */
2053 rtx d
= assign_temp (TREE_TYPE (exp
), 0, 1, 1);
2055 mark_temp_addr_taken (d
);
2056 structure_value_addr
= XEXP (d
, 0);
2060 #endif /* not PCC_STATIC_STRUCT_RETURN */
2063 /* Figure out the amount to which the stack should be aligned. */
2064 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2067 struct cgraph_rtl_info
*i
= cgraph_rtl_info (fndecl
);
2068 if (i
&& i
->preferred_incoming_stack_boundary
)
2069 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
2072 /* Operand 0 is a pointer-to-function; get the type of the function. */
2073 funtype
= TREE_TYPE (addr
);
2074 gcc_assert (POINTER_TYPE_P (funtype
));
2075 funtype
= TREE_TYPE (funtype
);
2077 /* Count whether there are actual complex arguments that need to be split
2078 into their real and imaginary parts. Munge the type_arg_types
2079 appropriately here as well. */
2080 if (targetm
.calls
.split_complex_arg
)
2082 call_expr_arg_iterator iter
;
2084 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2086 tree type
= TREE_TYPE (arg
);
2087 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
2088 && targetm
.calls
.split_complex_arg (type
))
2089 num_complex_actuals
++;
2091 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
2094 type_arg_types
= TYPE_ARG_TYPES (funtype
);
2096 if (flags
& ECF_MAY_BE_ALLOCA
)
2097 current_function_calls_alloca
= 1;
2099 /* If struct_value_rtx is 0, it means pass the address
2100 as if it were an extra parameter. Put the argument expression
2101 in structure_value_addr_value. */
2102 if (structure_value_addr
&& struct_value
== 0)
2104 /* If structure_value_addr is a REG other than
2105 virtual_outgoing_args_rtx, we can use always use it. If it
2106 is not a REG, we must always copy it into a register.
2107 If it is virtual_outgoing_args_rtx, we must copy it to another
2108 register in some cases. */
2109 rtx temp
= (!REG_P (structure_value_addr
)
2110 || (ACCUMULATE_OUTGOING_ARGS
2111 && stack_arg_under_construction
2112 && structure_value_addr
== virtual_outgoing_args_rtx
)
2113 ? copy_addr_to_reg (convert_memory_address
2114 (Pmode
, structure_value_addr
))
2115 : structure_value_addr
);
2117 structure_value_addr_value
=
2118 make_tree (build_pointer_type (TREE_TYPE (funtype
)), temp
);
2119 structure_value_addr_parm
= 1;
2122 /* Count the arguments and set NUM_ACTUALS. */
2124 call_expr_nargs (exp
) + num_complex_actuals
+ structure_value_addr_parm
;
2126 /* Compute number of named args.
2127 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2129 if (type_arg_types
!= 0)
2131 = (list_length (type_arg_types
)
2132 /* Count the struct value address, if it is passed as a parm. */
2133 + structure_value_addr_parm
);
2135 /* If we know nothing, treat all args as named. */
2136 n_named_args
= num_actuals
;
2138 /* Start updating where the next arg would go.
2140 On some machines (such as the PA) indirect calls have a different
2141 calling convention than normal calls. The fourth argument in
2142 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2144 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
2146 /* Now possibly adjust the number of named args.
2147 Normally, don't include the last named arg if anonymous args follow.
2148 We do include the last named arg if
2149 targetm.calls.strict_argument_naming() returns nonzero.
2150 (If no anonymous args follow, the result of list_length is actually
2151 one too large. This is harmless.)
2153 If targetm.calls.pretend_outgoing_varargs_named() returns
2154 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2155 this machine will be able to place unnamed args that were passed
2156 in registers into the stack. So treat all args as named. This
2157 allows the insns emitting for a specific argument list to be
2158 independent of the function declaration.
2160 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2161 we do not have any reliable way to pass unnamed args in
2162 registers, so we must force them into memory. */
2164 if (type_arg_types
!= 0
2165 && targetm
.calls
.strict_argument_naming (&args_so_far
))
2167 else if (type_arg_types
!= 0
2168 && ! targetm
.calls
.pretend_outgoing_varargs_named (&args_so_far
))
2169 /* Don't include the last named arg. */
2172 /* Treat all args as named. */
2173 n_named_args
= num_actuals
;
2175 /* Make a vector to hold all the information about each arg. */
2176 args
= alloca (num_actuals
* sizeof (struct arg_data
));
2177 memset (args
, 0, num_actuals
* sizeof (struct arg_data
));
2179 /* Build up entries in the ARGS array, compute the size of the
2180 arguments into ARGS_SIZE, etc. */
2181 initialize_argument_information (num_actuals
, args
, &args_size
,
2183 structure_value_addr_value
, fndecl
,
2184 &args_so_far
, reg_parm_stack_space
,
2185 &old_stack_level
, &old_pending_adj
,
2186 &must_preallocate
, &flags
,
2187 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
2191 /* If this function requires a variable-sized argument list, don't
2192 try to make a cse'able block for this call. We may be able to
2193 do this eventually, but it is too complicated to keep track of
2194 what insns go in the cse'able block and which don't. */
2196 flags
&= ~ECF_LIBCALL_BLOCK
;
2197 must_preallocate
= 1;
2200 /* Now make final decision about preallocating stack space. */
2201 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2205 /* If the structure value address will reference the stack pointer, we
2206 must stabilize it. We don't need to do this if we know that we are
2207 not going to adjust the stack pointer in processing this call. */
2209 if (structure_value_addr
2210 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2211 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2212 structure_value_addr
))
2214 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2215 structure_value_addr
= copy_to_reg (structure_value_addr
);
2217 /* Tail calls can make things harder to debug, and we've traditionally
2218 pushed these optimizations into -O2. Don't try if we're already
2219 expanding a call, as that means we're an argument. Don't try if
2220 there's cleanups, as we know there's code to follow the call. */
2222 if (currently_expanding_call
++ != 0
2223 || !flag_optimize_sibling_calls
2225 || lookup_stmt_eh_region (exp
) >= 0)
2228 /* Rest of purposes for tail call optimizations to fail. */
2230 #ifdef HAVE_sibcall_epilogue
2231 !HAVE_sibcall_epilogue
2236 /* Doing sibling call optimization needs some work, since
2237 structure_value_addr can be allocated on the stack.
2238 It does not seem worth the effort since few optimizable
2239 sibling calls will return a structure. */
2240 || structure_value_addr
!= NULL_RTX
2241 /* Check whether the target is able to optimize the call
2243 || !targetm
.function_ok_for_sibcall (fndecl
, exp
)
2244 /* Functions that do not return exactly once may not be sibcall
2246 || (flags
& (ECF_RETURNS_TWICE
| ECF_NORETURN
))
2247 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
)))
2248 /* If the called function is nested in the current one, it might access
2249 some of the caller's arguments, but could clobber them beforehand if
2250 the argument areas are shared. */
2251 || (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
2252 /* If this function requires more stack slots than the current
2253 function, we cannot change it into a sibling call.
2254 current_function_pretend_args_size is not part of the
2255 stack allocated by our caller. */
2256 || args_size
.constant
> (current_function_args_size
2257 - current_function_pretend_args_size
)
2258 /* If the callee pops its own arguments, then it must pop exactly
2259 the same number of arguments as the current function. */
2260 || (RETURN_POPS_ARGS (fndecl
, funtype
, args_size
.constant
)
2261 != RETURN_POPS_ARGS (current_function_decl
,
2262 TREE_TYPE (current_function_decl
),
2263 current_function_args_size
))
2264 || !lang_hooks
.decls
.ok_for_sibcall (fndecl
))
2267 /* Ensure current function's preferred stack boundary is at least
2268 what we need. We don't have to increase alignment for recursive
2270 if (cfun
->preferred_stack_boundary
< preferred_stack_boundary
2271 && fndecl
!= current_function_decl
)
2272 cfun
->preferred_stack_boundary
= preferred_stack_boundary
;
2273 if (fndecl
== current_function_decl
)
2274 cfun
->recursive_call_emit
= true;
2276 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2278 /* We want to make two insn chains; one for a sibling call, the other
2279 for a normal call. We will select one of the two chains after
2280 initial RTL generation is complete. */
2281 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
2283 int sibcall_failure
= 0;
2284 /* We want to emit any pending stack adjustments before the tail
2285 recursion "call". That way we know any adjustment after the tail
2286 recursion call can be ignored if we indeed use the tail
2288 int save_pending_stack_adjust
= 0;
2289 int save_stack_pointer_delta
= 0;
2291 rtx before_call
, next_arg_reg
;
2295 /* State variables we need to save and restore between
2297 save_pending_stack_adjust
= pending_stack_adjust
;
2298 save_stack_pointer_delta
= stack_pointer_delta
;
2301 flags
&= ~ECF_SIBCALL
;
2303 flags
|= ECF_SIBCALL
;
2305 /* Other state variables that we must reinitialize each time
2306 through the loop (that are not initialized by the loop itself). */
2310 /* Start a new sequence for the normal call case.
2312 From this point on, if the sibling call fails, we want to set
2313 sibcall_failure instead of continuing the loop. */
2316 /* Don't let pending stack adjusts add up to too much.
2317 Also, do all pending adjustments now if there is any chance
2318 this might be a call to alloca or if we are expanding a sibling
2319 call sequence or if we are calling a function that is to return
2320 with stack pointer depressed.
2321 Also do the adjustments before a throwing call, otherwise
2322 exception handling can fail; PR 19225. */
2323 if (pending_stack_adjust
>= 32
2324 || (pending_stack_adjust
> 0
2325 && (flags
& (ECF_MAY_BE_ALLOCA
| ECF_SP_DEPRESSED
)))
2326 || (pending_stack_adjust
> 0
2327 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
2329 do_pending_stack_adjust ();
2331 /* When calling a const function, we must pop the stack args right away,
2332 so that the pop is deleted or moved with the call. */
2333 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
2336 /* Precompute any arguments as needed. */
2338 precompute_arguments (flags
, num_actuals
, args
);
2340 /* Now we are about to start emitting insns that can be deleted
2341 if a libcall is deleted. */
2342 if (pass
&& (flags
& (ECF_LIBCALL_BLOCK
| ECF_MALLOC
)))
2345 if (pass
== 0 && cfun
->stack_protect_guard
)
2346 stack_protect_epilogue ();
2348 adjusted_args_size
= args_size
;
2349 /* Compute the actual size of the argument block required. The variable
2350 and constant sizes must be combined, the size may have to be rounded,
2351 and there may be a minimum required size. When generating a sibcall
2352 pattern, do not round up, since we'll be re-using whatever space our
2354 unadjusted_args_size
2355 = compute_argument_block_size (reg_parm_stack_space
,
2356 &adjusted_args_size
,
2358 : preferred_stack_boundary
));
2360 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2362 /* The argument block when performing a sibling call is the
2363 incoming argument block. */
2366 argblock
= virtual_incoming_args_rtx
;
2368 #ifdef STACK_GROWS_DOWNWARD
2369 = plus_constant (argblock
, current_function_pretend_args_size
);
2371 = plus_constant (argblock
, -current_function_pretend_args_size
);
2373 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2374 sbitmap_zero (stored_args_map
);
2377 /* If we have no actual push instructions, or shouldn't use them,
2378 make space for all args right now. */
2379 else if (adjusted_args_size
.var
!= 0)
2381 if (old_stack_level
== 0)
2383 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
2384 old_stack_pointer_delta
= stack_pointer_delta
;
2385 old_pending_adj
= pending_stack_adjust
;
2386 pending_stack_adjust
= 0;
2387 /* stack_arg_under_construction says whether a stack arg is
2388 being constructed at the old stack level. Pushing the stack
2389 gets a clean outgoing argument block. */
2390 old_stack_arg_under_construction
= stack_arg_under_construction
;
2391 stack_arg_under_construction
= 0;
2393 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2397 /* Note that we must go through the motions of allocating an argument
2398 block even if the size is zero because we may be storing args
2399 in the area reserved for register arguments, which may be part of
2402 int needed
= adjusted_args_size
.constant
;
2404 /* Store the maximum argument space used. It will be pushed by
2405 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2408 if (needed
> current_function_outgoing_args_size
)
2409 current_function_outgoing_args_size
= needed
;
2411 if (must_preallocate
)
2413 if (ACCUMULATE_OUTGOING_ARGS
)
2415 /* Since the stack pointer will never be pushed, it is
2416 possible for the evaluation of a parm to clobber
2417 something we have already written to the stack.
2418 Since most function calls on RISC machines do not use
2419 the stack, this is uncommon, but must work correctly.
2421 Therefore, we save any area of the stack that was already
2422 written and that we are using. Here we set up to do this
2423 by making a new stack usage map from the old one. The
2424 actual save will be done by store_one_arg.
2426 Another approach might be to try to reorder the argument
2427 evaluations to avoid this conflicting stack usage. */
2429 /* Since we will be writing into the entire argument area,
2430 the map must be allocated for its entire size, not just
2431 the part that is the responsibility of the caller. */
2432 if (!OUTGOING_REG_PARM_STACK_SPACE
)
2433 needed
+= reg_parm_stack_space
;
2435 #ifdef ARGS_GROW_DOWNWARD
2436 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2439 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2442 if (stack_usage_map_buf
)
2443 free (stack_usage_map_buf
);
2444 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
2445 stack_usage_map
= stack_usage_map_buf
;
2447 if (initial_highest_arg_in_use
)
2448 memcpy (stack_usage_map
, initial_stack_usage_map
,
2449 initial_highest_arg_in_use
);
2451 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2452 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2453 (highest_outgoing_arg_in_use
2454 - initial_highest_arg_in_use
));
2457 /* The address of the outgoing argument list must not be
2458 copied to a register here, because argblock would be left
2459 pointing to the wrong place after the call to
2460 allocate_dynamic_stack_space below. */
2462 argblock
= virtual_outgoing_args_rtx
;
2466 if (inhibit_defer_pop
== 0)
2468 /* Try to reuse some or all of the pending_stack_adjust
2469 to get this space. */
2471 = (combine_pending_stack_adjustment_and_call
2472 (unadjusted_args_size
,
2473 &adjusted_args_size
,
2474 preferred_unit_stack_boundary
));
2476 /* combine_pending_stack_adjustment_and_call computes
2477 an adjustment before the arguments are allocated.
2478 Account for them and see whether or not the stack
2479 needs to go up or down. */
2480 needed
= unadjusted_args_size
- needed
;
2484 /* We're releasing stack space. */
2485 /* ??? We can avoid any adjustment at all if we're
2486 already aligned. FIXME. */
2487 pending_stack_adjust
= -needed
;
2488 do_pending_stack_adjust ();
2492 /* We need to allocate space. We'll do that in
2493 push_block below. */
2494 pending_stack_adjust
= 0;
2497 /* Special case this because overhead of `push_block' in
2498 this case is non-trivial. */
2500 argblock
= virtual_outgoing_args_rtx
;
2503 argblock
= push_block (GEN_INT (needed
), 0, 0);
2504 #ifdef ARGS_GROW_DOWNWARD
2505 argblock
= plus_constant (argblock
, needed
);
2509 /* We only really need to call `copy_to_reg' in the case
2510 where push insns are going to be used to pass ARGBLOCK
2511 to a function call in ARGS. In that case, the stack
2512 pointer changes value from the allocation point to the
2513 call point, and hence the value of
2514 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2515 as well always do it. */
2516 argblock
= copy_to_reg (argblock
);
2521 if (ACCUMULATE_OUTGOING_ARGS
)
2523 /* The save/restore code in store_one_arg handles all
2524 cases except one: a constructor call (including a C
2525 function returning a BLKmode struct) to initialize
2527 if (stack_arg_under_construction
)
2530 = GEN_INT (adjusted_args_size
.constant
2531 + (OUTGOING_REG_PARM_STACK_SPACE
? 0
2532 : reg_parm_stack_space
));
2533 if (old_stack_level
== 0)
2535 emit_stack_save (SAVE_BLOCK
, &old_stack_level
,
2537 old_stack_pointer_delta
= stack_pointer_delta
;
2538 old_pending_adj
= pending_stack_adjust
;
2539 pending_stack_adjust
= 0;
2540 /* stack_arg_under_construction says whether a stack
2541 arg is being constructed at the old stack level.
2542 Pushing the stack gets a clean outgoing argument
2544 old_stack_arg_under_construction
2545 = stack_arg_under_construction
;
2546 stack_arg_under_construction
= 0;
2547 /* Make a new map for the new argument list. */
2548 if (stack_usage_map_buf
)
2549 free (stack_usage_map_buf
);
2550 stack_usage_map_buf
= XCNEWVEC (char, highest_outgoing_arg_in_use
);
2551 stack_usage_map
= stack_usage_map_buf
;
2552 highest_outgoing_arg_in_use
= 0;
2554 allocate_dynamic_stack_space (push_size
, NULL_RTX
,
2558 /* If argument evaluation might modify the stack pointer,
2559 copy the address of the argument list to a register. */
2560 for (i
= 0; i
< num_actuals
; i
++)
2561 if (args
[i
].pass_on_stack
)
2563 argblock
= copy_addr_to_reg (argblock
);
2568 compute_argument_addresses (args
, argblock
, num_actuals
);
2570 /* If we push args individually in reverse order, perform stack alignment
2571 before the first push (the last arg). */
2572 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2573 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2575 /* When the stack adjustment is pending, we get better code
2576 by combining the adjustments. */
2577 if (pending_stack_adjust
2578 && ! (flags
& ECF_LIBCALL_BLOCK
)
2579 && ! inhibit_defer_pop
)
2581 pending_stack_adjust
2582 = (combine_pending_stack_adjustment_and_call
2583 (unadjusted_args_size
,
2584 &adjusted_args_size
,
2585 preferred_unit_stack_boundary
));
2586 do_pending_stack_adjust ();
2588 else if (argblock
== 0)
2589 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2590 - unadjusted_args_size
));
2592 /* Now that the stack is properly aligned, pops can't safely
2593 be deferred during the evaluation of the arguments. */
2596 funexp
= rtx_for_function_call (fndecl
, addr
);
2598 /* Figure out the register where the value, if any, will come back. */
2600 if (TYPE_MODE (TREE_TYPE (exp
)) != VOIDmode
2601 && ! structure_value_addr
)
2603 if (pcc_struct_value
)
2604 valreg
= hard_function_value (build_pointer_type (TREE_TYPE (exp
)),
2605 fndecl
, NULL
, (pass
== 0));
2607 valreg
= hard_function_value (TREE_TYPE (exp
), fndecl
, fntype
,
2610 /* If VALREG is a PARALLEL whose first member has a zero
2611 offset, use that. This is for targets such as m68k that
2612 return the same value in multiple places. */
2613 if (GET_CODE (valreg
) == PARALLEL
)
2615 rtx elem
= XVECEXP (valreg
, 0, 0);
2616 rtx where
= XEXP (elem
, 0);
2617 rtx offset
= XEXP (elem
, 1);
2618 if (offset
== const0_rtx
2619 && GET_MODE (where
) == GET_MODE (valreg
))
2624 /* Precompute all register parameters. It isn't safe to compute anything
2625 once we have started filling any specific hard regs. */
2626 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2628 if (CALL_EXPR_STATIC_CHAIN (exp
))
2629 static_chain_value
= expand_normal (CALL_EXPR_STATIC_CHAIN (exp
));
2631 static_chain_value
= 0;
2633 #ifdef REG_PARM_STACK_SPACE
2634 /* Save the fixed argument area if it's part of the caller's frame and
2635 is clobbered by argument setup for this call. */
2636 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2637 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2638 &low_to_save
, &high_to_save
);
2641 /* Now store (and compute if necessary) all non-register parms.
2642 These come before register parms, since they can require block-moves,
2643 which could clobber the registers used for register parms.
2644 Parms which have partial registers are not stored here,
2645 but we do preallocate space here if they want that. */
2647 for (i
= 0; i
< num_actuals
; i
++)
2648 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2650 rtx before_arg
= get_last_insn ();
2652 if (store_one_arg (&args
[i
], argblock
, flags
,
2653 adjusted_args_size
.var
!= 0,
2654 reg_parm_stack_space
)
2656 && check_sibcall_argument_overlap (before_arg
,
2658 sibcall_failure
= 1;
2660 if (flags
& ECF_CONST
2662 && args
[i
].value
== args
[i
].stack
)
2663 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
2664 gen_rtx_USE (VOIDmode
,
2669 /* If we have a parm that is passed in registers but not in memory
2670 and whose alignment does not permit a direct copy into registers,
2671 make a group of pseudos that correspond to each register that we
2673 if (STRICT_ALIGNMENT
)
2674 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2676 /* Now store any partially-in-registers parm.
2677 This is the last place a block-move can happen. */
2679 for (i
= 0; i
< num_actuals
; i
++)
2680 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2682 rtx before_arg
= get_last_insn ();
2684 if (store_one_arg (&args
[i
], argblock
, flags
,
2685 adjusted_args_size
.var
!= 0,
2686 reg_parm_stack_space
)
2688 && check_sibcall_argument_overlap (before_arg
,
2690 sibcall_failure
= 1;
2693 /* If we pushed args in forward order, perform stack alignment
2694 after pushing the last arg. */
2695 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
2696 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2697 - unadjusted_args_size
));
2699 /* If register arguments require space on the stack and stack space
2700 was not preallocated, allocate stack space here for arguments
2701 passed in registers. */
2702 if (OUTGOING_REG_PARM_STACK_SPACE
&& !ACCUMULATE_OUTGOING_ARGS
2703 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
2704 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
2706 /* Pass the function the address in which to return a
2708 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
2710 structure_value_addr
2711 = convert_memory_address (Pmode
, structure_value_addr
);
2712 emit_move_insn (struct_value
,
2714 force_operand (structure_value_addr
,
2717 if (REG_P (struct_value
))
2718 use_reg (&call_fusage
, struct_value
);
2721 funexp
= prepare_call_address (funexp
, static_chain_value
,
2722 &call_fusage
, reg_parm_seen
, pass
== 0);
2724 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
2725 pass
== 0, &sibcall_failure
);
2727 /* Save a pointer to the last insn before the call, so that we can
2728 later safely search backwards to find the CALL_INSN. */
2729 before_call
= get_last_insn ();
2731 /* Set up next argument register. For sibling calls on machines
2732 with register windows this should be the incoming register. */
2733 #ifdef FUNCTION_INCOMING_ARG
2735 next_arg_reg
= FUNCTION_INCOMING_ARG (args_so_far
, VOIDmode
,
2739 next_arg_reg
= FUNCTION_ARG (args_so_far
, VOIDmode
,
2742 /* All arguments and registers used for the call must be set up by
2745 /* Stack must be properly aligned now. */
2747 || !(stack_pointer_delta
% preferred_unit_stack_boundary
));
2749 /* Generate the actual call instruction. */
2750 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
2751 adjusted_args_size
.constant
, struct_value_size
,
2752 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
2753 flags
, & args_so_far
);
2755 /* If a non-BLKmode value is returned at the most significant end
2756 of a register, shift the register right by the appropriate amount
2757 and update VALREG accordingly. BLKmode values are handled by the
2758 group load/store machinery below. */
2759 if (!structure_value_addr
2760 && !pcc_struct_value
2761 && TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
2762 && targetm
.calls
.return_in_msb (TREE_TYPE (exp
)))
2764 if (shift_return_value (TYPE_MODE (TREE_TYPE (exp
)), false, valreg
))
2765 sibcall_failure
= 1;
2766 valreg
= gen_rtx_REG (TYPE_MODE (TREE_TYPE (exp
)), REGNO (valreg
));
2769 /* If call is cse'able, make appropriate pair of reg-notes around it.
2770 Test valreg so we don't crash; may safely ignore `const'
2771 if return type is void. Disable for PARALLEL return values, because
2772 we have no way to move such values into a pseudo register. */
2773 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
2777 bool failed
= valreg
== 0 || GET_CODE (valreg
) == PARALLEL
;
2779 insns
= get_insns ();
2781 /* Expansion of block moves possibly introduced a loop that may
2782 not appear inside libcall block. */
2783 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
2795 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2797 /* Mark the return value as a pointer if needed. */
2798 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
2799 mark_reg_pointer (temp
,
2800 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp
))));
2803 if (flag_unsafe_math_optimizations
2805 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
2806 && (DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRT
2807 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRTF
2808 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRTL
))
2809 note
= gen_rtx_fmt_e (SQRT
,
2811 args
[0].initial_value
);
2814 /* Construct an "equal form" for the value which
2815 mentions all the arguments in order as well as
2816 the function name. */
2817 for (i
= 0; i
< num_actuals
; i
++)
2818 note
= gen_rtx_EXPR_LIST (VOIDmode
,
2819 args
[i
].initial_value
, note
);
2820 note
= gen_rtx_EXPR_LIST (VOIDmode
, funexp
, note
);
2822 if (flags
& ECF_PURE
)
2823 note
= gen_rtx_EXPR_LIST (VOIDmode
,
2824 gen_rtx_USE (VOIDmode
,
2825 gen_rtx_MEM (BLKmode
,
2826 gen_rtx_SCRATCH (VOIDmode
))),
2829 emit_libcall_block (insns
, temp
, valreg
, note
);
2834 else if (pass
&& (flags
& ECF_MALLOC
))
2836 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2839 /* The return value from a malloc-like function is a pointer. */
2840 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
2841 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
2843 emit_move_insn (temp
, valreg
);
2845 /* The return value from a malloc-like function can not alias
2847 last
= get_last_insn ();
2849 gen_rtx_EXPR_LIST (REG_NOALIAS
, temp
, REG_NOTES (last
));
2851 /* Write out the sequence. */
2852 insns
= get_insns ();
2858 /* For calls to `setjmp', etc., inform flow.c it should complain
2859 if nonvolatile values are live. For functions that cannot return,
2860 inform flow that control does not fall through. */
2862 if ((flags
& ECF_NORETURN
) || pass
== 0)
2864 /* The barrier must be emitted
2865 immediately after the CALL_INSN. Some ports emit more
2866 than just a CALL_INSN above, so we must search for it here. */
2868 rtx last
= get_last_insn ();
2869 while (!CALL_P (last
))
2871 last
= PREV_INSN (last
);
2872 /* There was no CALL_INSN? */
2873 gcc_assert (last
!= before_call
);
2876 emit_barrier_after (last
);
2878 /* Stack adjustments after a noreturn call are dead code.
2879 However when NO_DEFER_POP is in effect, we must preserve
2880 stack_pointer_delta. */
2881 if (inhibit_defer_pop
== 0)
2883 stack_pointer_delta
= old_stack_allocated
;
2884 pending_stack_adjust
= 0;
2888 /* If value type not void, return an rtx for the value. */
2890 if (TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
2892 target
= const0_rtx
;
2893 else if (structure_value_addr
)
2895 if (target
== 0 || !MEM_P (target
))
2898 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
2899 memory_address (TYPE_MODE (TREE_TYPE (exp
)),
2900 structure_value_addr
));
2901 set_mem_attributes (target
, exp
, 1);
2904 else if (pcc_struct_value
)
2906 /* This is the special C++ case where we need to
2907 know what the true target was. We take care to
2908 never use this value more than once in one expression. */
2909 target
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
2910 copy_to_reg (valreg
));
2911 set_mem_attributes (target
, exp
, 1);
2913 /* Handle calls that return values in multiple non-contiguous locations.
2914 The Irix 6 ABI has examples of this. */
2915 else if (GET_CODE (valreg
) == PARALLEL
)
2919 /* This will only be assigned once, so it can be readonly. */
2920 tree nt
= build_qualified_type (TREE_TYPE (exp
),
2921 (TYPE_QUALS (TREE_TYPE (exp
))
2922 | TYPE_QUAL_CONST
));
2924 target
= assign_temp (nt
, 0, 1, 1);
2927 if (! rtx_equal_p (target
, valreg
))
2928 emit_group_store (target
, valreg
, TREE_TYPE (exp
),
2929 int_size_in_bytes (TREE_TYPE (exp
)));
2931 /* We can not support sibling calls for this case. */
2932 sibcall_failure
= 1;
2935 && GET_MODE (target
) == TYPE_MODE (TREE_TYPE (exp
))
2936 && GET_MODE (target
) == GET_MODE (valreg
))
2938 bool may_overlap
= false;
2940 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
2941 reg to a plain register. */
2943 && HARD_REGISTER_P (valreg
)
2944 && CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (REGNO (valreg
)))
2945 && !(REG_P (target
) && !HARD_REGISTER_P (target
)))
2946 valreg
= copy_to_reg (valreg
);
2948 /* If TARGET is a MEM in the argument area, and we have
2949 saved part of the argument area, then we can't store
2950 directly into TARGET as it may get overwritten when we
2951 restore the argument save area below. Don't work too
2952 hard though and simply force TARGET to a register if it
2953 is a MEM; the optimizer is quite likely to sort it out. */
2954 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
2955 for (i
= 0; i
< num_actuals
; i
++)
2956 if (args
[i
].save_area
)
2963 target
= copy_to_reg (valreg
);
2966 /* TARGET and VALREG cannot be equal at this point
2967 because the latter would not have
2968 REG_FUNCTION_VALUE_P true, while the former would if
2969 it were referring to the same register.
2971 If they refer to the same register, this move will be
2972 a no-op, except when function inlining is being
2974 emit_move_insn (target
, valreg
);
2976 /* If we are setting a MEM, this code must be executed.
2977 Since it is emitted after the call insn, sibcall
2978 optimization cannot be performed in that case. */
2980 sibcall_failure
= 1;
2983 else if (TYPE_MODE (TREE_TYPE (exp
)) == BLKmode
)
2985 target
= copy_blkmode_from_reg (target
, valreg
, TREE_TYPE (exp
));
2987 /* We can not support sibling calls for this case. */
2988 sibcall_failure
= 1;
2991 target
= copy_to_reg (valreg
);
2993 if (targetm
.calls
.promote_function_return(funtype
))
2995 /* If we promoted this return value, make the proper SUBREG.
2996 TARGET might be const0_rtx here, so be careful. */
2998 && TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
2999 && GET_MODE (target
) != TYPE_MODE (TREE_TYPE (exp
)))
3001 tree type
= TREE_TYPE (exp
);
3002 int unsignedp
= TYPE_UNSIGNED (type
);
3004 enum machine_mode pmode
;
3006 pmode
= promote_mode (type
, TYPE_MODE (type
), &unsignedp
, 1);
3007 /* If we don't promote as expected, something is wrong. */
3008 gcc_assert (GET_MODE (target
) == pmode
);
3010 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
3011 && (GET_MODE_SIZE (GET_MODE (target
))
3012 > GET_MODE_SIZE (TYPE_MODE (type
))))
3014 offset
= GET_MODE_SIZE (GET_MODE (target
))
3015 - GET_MODE_SIZE (TYPE_MODE (type
));
3016 if (! BYTES_BIG_ENDIAN
)
3017 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
3018 else if (! WORDS_BIG_ENDIAN
)
3019 offset
%= UNITS_PER_WORD
;
3021 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
3022 SUBREG_PROMOTED_VAR_P (target
) = 1;
3023 SUBREG_PROMOTED_UNSIGNED_SET (target
, unsignedp
);
3027 /* If size of args is variable or this was a constructor call for a stack
3028 argument, restore saved stack-pointer value. */
3030 if (old_stack_level
&& ! (flags
& ECF_SP_DEPRESSED
))
3032 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
3033 stack_pointer_delta
= old_stack_pointer_delta
;
3034 pending_stack_adjust
= old_pending_adj
;
3035 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
3036 stack_arg_under_construction
= old_stack_arg_under_construction
;
3037 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3038 stack_usage_map
= initial_stack_usage_map
;
3039 sibcall_failure
= 1;
3041 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
3043 #ifdef REG_PARM_STACK_SPACE
3045 restore_fixed_argument_area (save_area
, argblock
,
3046 high_to_save
, low_to_save
);
3049 /* If we saved any argument areas, restore them. */
3050 for (i
= 0; i
< num_actuals
; i
++)
3051 if (args
[i
].save_area
)
3053 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
3055 = gen_rtx_MEM (save_mode
,
3056 memory_address (save_mode
,
3057 XEXP (args
[i
].stack_slot
, 0)));
3059 if (save_mode
!= BLKmode
)
3060 emit_move_insn (stack_area
, args
[i
].save_area
);
3062 emit_block_move (stack_area
, args
[i
].save_area
,
3063 GEN_INT (args
[i
].locate
.size
.constant
),
3064 BLOCK_OP_CALL_PARM
);
3067 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3068 stack_usage_map
= initial_stack_usage_map
;
3071 /* If this was alloca, record the new stack level for nonlocal gotos.
3072 Check for the handler slots since we might not have a save area
3073 for non-local gotos. */
3075 if ((flags
& ECF_MAY_BE_ALLOCA
) && cfun
->nonlocal_goto_save_area
!= 0)
3076 update_nonlocal_goto_save_area ();
3078 /* Free up storage we no longer need. */
3079 for (i
= 0; i
< num_actuals
; ++i
)
3080 if (args
[i
].aligned_regs
)
3081 free (args
[i
].aligned_regs
);
3083 insns
= get_insns ();
3088 tail_call_insns
= insns
;
3090 /* Restore the pending stack adjustment now that we have
3091 finished generating the sibling call sequence. */
3093 pending_stack_adjust
= save_pending_stack_adjust
;
3094 stack_pointer_delta
= save_stack_pointer_delta
;
3096 /* Prepare arg structure for next iteration. */
3097 for (i
= 0; i
< num_actuals
; i
++)
3100 args
[i
].aligned_regs
= 0;
3104 sbitmap_free (stored_args_map
);
3108 normal_call_insns
= insns
;
3110 /* Verify that we've deallocated all the stack we used. */
3111 gcc_assert ((flags
& ECF_NORETURN
)
3112 || (old_stack_allocated
3113 == stack_pointer_delta
- pending_stack_adjust
));
3116 /* If something prevents making this a sibling call,
3117 zero out the sequence. */
3118 if (sibcall_failure
)
3119 tail_call_insns
= NULL_RTX
;
3124 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3125 arguments too, as argument area is now clobbered by the call. */
3126 if (tail_call_insns
)
3128 emit_insn (tail_call_insns
);
3129 cfun
->tail_call_emit
= true;
3132 emit_insn (normal_call_insns
);
3134 currently_expanding_call
--;
3136 /* If this function returns with the stack pointer depressed, ensure
3137 this block saves and restores the stack pointer, show it was
3138 changed, and adjust for any outgoing arg space. */
3139 if (flags
& ECF_SP_DEPRESSED
)
3141 clear_pending_stack_adjust ();
3142 emit_insn (gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
));
3143 emit_move_insn (virtual_stack_dynamic_rtx
, stack_pointer_rtx
);
3146 if (stack_usage_map_buf
)
3147 free (stack_usage_map_buf
);
3152 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3153 this function's incoming arguments.
3155 At the start of RTL generation we know the only REG_EQUIV notes
3156 in the rtl chain are those for incoming arguments, so we can look
3157 for REG_EQUIV notes between the start of the function and the
3158 NOTE_INSN_FUNCTION_BEG.
3160 This is (slight) overkill. We could keep track of the highest
3161 argument we clobber and be more selective in removing notes, but it
3162 does not seem to be worth the effort. */
3165 fixup_tail_calls (void)
3169 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
3173 /* There are never REG_EQUIV notes for the incoming arguments
3174 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3176 && NOTE_LINE_NUMBER (insn
) == NOTE_INSN_FUNCTION_BEG
)
3179 note
= find_reg_note (insn
, REG_EQUIV
, 0);
3181 remove_note (insn
, note
);
3182 note
= find_reg_note (insn
, REG_EQUIV
, 0);
3187 /* Traverse a list of TYPES and expand all complex types into their
3190 split_complex_types (tree types
)
3194 /* Before allocating memory, check for the common case of no complex. */
3195 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3197 tree type
= TREE_VALUE (p
);
3198 if (TREE_CODE (type
) == COMPLEX_TYPE
3199 && targetm
.calls
.split_complex_arg (type
))
3205 types
= copy_list (types
);
3207 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3209 tree complex_type
= TREE_VALUE (p
);
3211 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
3212 && targetm
.calls
.split_complex_arg (complex_type
))
3216 /* Rewrite complex type with component type. */
3217 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
3218 next
= TREE_CHAIN (p
);
3220 /* Add another component type for the imaginary part. */
3221 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
3222 TREE_CHAIN (p
) = imag
;
3223 TREE_CHAIN (imag
) = next
;
3225 /* Skip the newly created node. */
3233 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3234 The RETVAL parameter specifies whether return value needs to be saved, other
3235 parameters are documented in the emit_library_call function below. */
3238 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
3239 enum libcall_type fn_type
,
3240 enum machine_mode outmode
, int nargs
, va_list p
)
3242 /* Total size in bytes of all the stack-parms scanned so far. */
3243 struct args_size args_size
;
3244 /* Size of arguments before any adjustments (such as rounding). */
3245 struct args_size original_args_size
;
3251 CUMULATIVE_ARGS args_so_far
;
3255 enum machine_mode mode
;
3258 struct locate_and_pad_arg_data locate
;
3262 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3263 rtx call_fusage
= 0;
3266 int pcc_struct_value
= 0;
3267 int struct_value_size
= 0;
3269 int reg_parm_stack_space
= 0;
3272 tree tfom
; /* type_for_mode (outmode, 0) */
3274 #ifdef REG_PARM_STACK_SPACE
3275 /* Define the boundary of the register parm stack space that needs to be
3277 int low_to_save
, high_to_save
;
3278 rtx save_area
= 0; /* Place that it is saved. */
3281 /* Size of the stack reserved for parameter registers. */
3282 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3283 char *initial_stack_usage_map
= stack_usage_map
;
3284 char *stack_usage_map_buf
= NULL
;
3286 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
3288 #ifdef REG_PARM_STACK_SPACE
3289 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3292 /* By default, library functions can not throw. */
3293 flags
= ECF_NOTHROW
;
3305 case LCT_CONST_MAKE_BLOCK
:
3306 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
3308 case LCT_PURE_MAKE_BLOCK
:
3309 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
3312 flags
|= ECF_NORETURN
;
3315 flags
= ECF_NORETURN
;
3317 case LCT_RETURNS_TWICE
:
3318 flags
= ECF_RETURNS_TWICE
;
3323 /* Ensure current function's preferred stack boundary is at least
3325 if (cfun
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3326 cfun
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3328 /* If this kind of value comes back in memory,
3329 decide where in memory it should come back. */
3330 if (outmode
!= VOIDmode
)
3332 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
3333 if (aggregate_value_p (tfom
, 0))
3335 #ifdef PCC_STATIC_STRUCT_RETURN
3337 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
3338 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3339 pcc_struct_value
= 1;
3341 value
= gen_reg_rtx (outmode
);
3342 #else /* not PCC_STATIC_STRUCT_RETURN */
3343 struct_value_size
= GET_MODE_SIZE (outmode
);
3344 if (value
!= 0 && MEM_P (value
))
3347 mem_value
= assign_temp (tfom
, 0, 1, 1);
3349 /* This call returns a big structure. */
3350 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3354 tfom
= void_type_node
;
3356 /* ??? Unfinished: must pass the memory address as an argument. */
3358 /* Copy all the libcall-arguments out of the varargs data
3359 and into a vector ARGVEC.
3361 Compute how to pass each argument. We only support a very small subset
3362 of the full argument passing conventions to limit complexity here since
3363 library functions shouldn't have many args. */
3365 argvec
= alloca ((nargs
+ 1) * sizeof (struct arg
));
3366 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3368 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3369 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3371 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0, nargs
);
3374 args_size
.constant
= 0;
3379 /* Now we are about to start emitting insns that can be deleted
3380 if a libcall is deleted. */
3381 if (flags
& ECF_LIBCALL_BLOCK
)
3386 /* If there's a structure value address to be passed,
3387 either pass it in the special place, or pass it as an extra argument. */
3388 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
3390 rtx addr
= XEXP (mem_value
, 0);
3394 /* Make sure it is a reasonable operand for a move or push insn. */
3395 if (!REG_P (addr
) && !MEM_P (addr
)
3396 && ! (CONSTANT_P (addr
) && LEGITIMATE_CONSTANT_P (addr
)))
3397 addr
= force_operand (addr
, NULL_RTX
);
3399 argvec
[count
].value
= addr
;
3400 argvec
[count
].mode
= Pmode
;
3401 argvec
[count
].partial
= 0;
3403 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, Pmode
, NULL_TREE
, 1);
3404 gcc_assert (targetm
.calls
.arg_partial_bytes (&args_so_far
, Pmode
,
3405 NULL_TREE
, 1) == 0);
3407 locate_and_pad_parm (Pmode
, NULL_TREE
,
3408 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3411 argvec
[count
].reg
!= 0,
3413 0, NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3415 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3416 || reg_parm_stack_space
> 0)
3417 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3419 FUNCTION_ARG_ADVANCE (args_so_far
, Pmode
, (tree
) 0, 1);
3424 for (; count
< nargs
; count
++)
3426 rtx val
= va_arg (p
, rtx
);
3427 enum machine_mode mode
= va_arg (p
, enum machine_mode
);
3429 /* We cannot convert the arg value to the mode the library wants here;
3430 must do it earlier where we know the signedness of the arg. */
3431 gcc_assert (mode
!= BLKmode
3432 && (GET_MODE (val
) == mode
|| GET_MODE (val
) == VOIDmode
));
3434 /* Make sure it is a reasonable operand for a move or push insn. */
3435 if (!REG_P (val
) && !MEM_P (val
)
3436 && ! (CONSTANT_P (val
) && LEGITIMATE_CONSTANT_P (val
)))
3437 val
= force_operand (val
, NULL_RTX
);
3439 if (pass_by_reference (&args_so_far
, mode
, NULL_TREE
, 1))
3443 = !reference_callee_copied (&args_so_far
, mode
, NULL_TREE
, 1);
3445 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3446 functions, so we have to pretend this isn't such a function. */
3447 if (flags
& ECF_LIBCALL_BLOCK
)
3449 rtx insns
= get_insns ();
3453 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3455 /* If this was a CONST function, it is now PURE since
3456 it now reads memory. */
3457 if (flags
& ECF_CONST
)
3459 flags
&= ~ECF_CONST
;
3463 if (GET_MODE (val
) == MEM
&& !must_copy
)
3467 slot
= assign_temp (lang_hooks
.types
.type_for_mode (mode
, 0),
3469 emit_move_insn (slot
, val
);
3472 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3473 gen_rtx_USE (VOIDmode
, slot
),
3476 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3477 gen_rtx_CLOBBER (VOIDmode
,
3482 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3485 argvec
[count
].value
= val
;
3486 argvec
[count
].mode
= mode
;
3488 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, mode
, NULL_TREE
, 1);
3490 argvec
[count
].partial
3491 = targetm
.calls
.arg_partial_bytes (&args_so_far
, mode
, NULL_TREE
, 1);
3493 locate_and_pad_parm (mode
, NULL_TREE
,
3494 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3497 argvec
[count
].reg
!= 0,
3499 argvec
[count
].partial
,
3500 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3502 gcc_assert (!argvec
[count
].locate
.size
.var
);
3504 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3505 || reg_parm_stack_space
> 0)
3506 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3508 FUNCTION_ARG_ADVANCE (args_so_far
, mode
, (tree
) 0, 1);
3511 /* If this machine requires an external definition for library
3512 functions, write one out. */
3513 assemble_external_libcall (fun
);
3515 original_args_size
= args_size
;
3516 args_size
.constant
= (((args_size
.constant
3517 + stack_pointer_delta
3521 - stack_pointer_delta
);
3523 args_size
.constant
= MAX (args_size
.constant
,
3524 reg_parm_stack_space
);
3526 if (!OUTGOING_REG_PARM_STACK_SPACE
)
3527 args_size
.constant
-= reg_parm_stack_space
;
3529 if (args_size
.constant
> current_function_outgoing_args_size
)
3530 current_function_outgoing_args_size
= args_size
.constant
;
3532 if (ACCUMULATE_OUTGOING_ARGS
)
3534 /* Since the stack pointer will never be pushed, it is possible for
3535 the evaluation of a parm to clobber something we have already
3536 written to the stack. Since most function calls on RISC machines
3537 do not use the stack, this is uncommon, but must work correctly.
3539 Therefore, we save any area of the stack that was already written
3540 and that we are using. Here we set up to do this by making a new
3541 stack usage map from the old one.
3543 Another approach might be to try to reorder the argument
3544 evaluations to avoid this conflicting stack usage. */
3546 needed
= args_size
.constant
;
3548 /* Since we will be writing into the entire argument area, the
3549 map must be allocated for its entire size, not just the part that
3550 is the responsibility of the caller. */
3551 if (!OUTGOING_REG_PARM_STACK_SPACE
)
3552 needed
+= reg_parm_stack_space
;
3554 #ifdef ARGS_GROW_DOWNWARD
3555 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3558 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3561 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
3562 stack_usage_map
= stack_usage_map_buf
;
3564 if (initial_highest_arg_in_use
)
3565 memcpy (stack_usage_map
, initial_stack_usage_map
,
3566 initial_highest_arg_in_use
);
3568 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3569 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3570 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3573 /* We must be careful to use virtual regs before they're instantiated,
3574 and real regs afterwards. Loop optimization, for example, can create
3575 new libcalls after we've instantiated the virtual regs, and if we
3576 use virtuals anyway, they won't match the rtl patterns. */
3578 if (virtuals_instantiated
)
3579 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3581 argblock
= virtual_outgoing_args_rtx
;
3586 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3589 /* If we push args individually in reverse order, perform stack alignment
3590 before the first push (the last arg). */
3591 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3592 anti_adjust_stack (GEN_INT (args_size
.constant
3593 - original_args_size
.constant
));
3595 if (PUSH_ARGS_REVERSED
)
3606 #ifdef REG_PARM_STACK_SPACE
3607 if (ACCUMULATE_OUTGOING_ARGS
)
3609 /* The argument list is the property of the called routine and it
3610 may clobber it. If the fixed area has been used for previous
3611 parameters, we must save and restore it. */
3612 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
3613 &low_to_save
, &high_to_save
);
3617 /* Push the args that need to be pushed. */
3619 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3620 are to be pushed. */
3621 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3623 enum machine_mode mode
= argvec
[argnum
].mode
;
3624 rtx val
= argvec
[argnum
].value
;
3625 rtx reg
= argvec
[argnum
].reg
;
3626 int partial
= argvec
[argnum
].partial
;
3627 int lower_bound
= 0, upper_bound
= 0, i
;
3629 if (! (reg
!= 0 && partial
== 0))
3631 if (ACCUMULATE_OUTGOING_ARGS
)
3633 /* If this is being stored into a pre-allocated, fixed-size,
3634 stack area, save any previous data at that location. */
3636 #ifdef ARGS_GROW_DOWNWARD
3637 /* stack_slot is negative, but we want to index stack_usage_map
3638 with positive values. */
3639 upper_bound
= -argvec
[argnum
].locate
.offset
.constant
+ 1;
3640 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
3642 lower_bound
= argvec
[argnum
].locate
.offset
.constant
;
3643 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
3647 /* Don't worry about things in the fixed argument area;
3648 it has already been saved. */
3649 if (i
< reg_parm_stack_space
)
3650 i
= reg_parm_stack_space
;
3651 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
3654 if (i
< upper_bound
)
3656 /* We need to make a save area. */
3658 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
3659 enum machine_mode save_mode
3660 = mode_for_size (size
, MODE_INT
, 1);
3662 = plus_constant (argblock
,
3663 argvec
[argnum
].locate
.offset
.constant
);
3665 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
3667 if (save_mode
== BLKmode
)
3669 argvec
[argnum
].save_area
3670 = assign_stack_temp (BLKmode
,
3671 argvec
[argnum
].locate
.size
.constant
,
3674 emit_block_move (validize_mem (argvec
[argnum
].save_area
),
3676 GEN_INT (argvec
[argnum
].locate
.size
.constant
),
3677 BLOCK_OP_CALL_PARM
);
3681 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3683 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3688 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, PARM_BOUNDARY
,
3689 partial
, reg
, 0, argblock
,
3690 GEN_INT (argvec
[argnum
].locate
.offset
.constant
),
3691 reg_parm_stack_space
,
3692 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
));
3694 /* Now mark the segment we just used. */
3695 if (ACCUMULATE_OUTGOING_ARGS
)
3696 for (i
= lower_bound
; i
< upper_bound
; i
++)
3697 stack_usage_map
[i
] = 1;
3701 if (flags
& ECF_CONST
)
3705 /* Indicate argument access so that alias.c knows that these
3708 use
= plus_constant (argblock
,
3709 argvec
[argnum
].locate
.offset
.constant
);
3711 /* When arguments are pushed, trying to tell alias.c where
3712 exactly this argument is won't work, because the
3713 auto-increment causes confusion. So we merely indicate
3714 that we access something with a known mode somewhere on
3716 use
= gen_rtx_PLUS (Pmode
, virtual_outgoing_args_rtx
,
3717 gen_rtx_SCRATCH (Pmode
));
3718 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
3719 use
= gen_rtx_USE (VOIDmode
, use
);
3720 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
3725 /* If we pushed args in forward order, perform stack alignment
3726 after pushing the last arg. */
3727 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3728 anti_adjust_stack (GEN_INT (args_size
.constant
3729 - original_args_size
.constant
));
3731 if (PUSH_ARGS_REVERSED
)
3736 fun
= prepare_call_address (fun
, NULL
, &call_fusage
, 0, 0);
3738 /* Now load any reg parms into their regs. */
3740 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3741 are to be pushed. */
3742 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3744 enum machine_mode mode
= argvec
[argnum
].mode
;
3745 rtx val
= argvec
[argnum
].value
;
3746 rtx reg
= argvec
[argnum
].reg
;
3747 int partial
= argvec
[argnum
].partial
;
3749 /* Handle calls that pass values in multiple non-contiguous
3750 locations. The PA64 has examples of this for library calls. */
3751 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3752 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
3753 else if (reg
!= 0 && partial
== 0)
3754 emit_move_insn (reg
, val
);
3759 /* Any regs containing parms remain in use through the call. */
3760 for (count
= 0; count
< nargs
; count
++)
3762 rtx reg
= argvec
[count
].reg
;
3763 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3764 use_group_regs (&call_fusage
, reg
);
3767 int partial
= argvec
[count
].partial
;
3771 gcc_assert (partial
% UNITS_PER_WORD
== 0);
3772 nregs
= partial
/ UNITS_PER_WORD
;
3773 use_regs (&call_fusage
, REGNO (reg
), nregs
);
3776 use_reg (&call_fusage
, reg
);
3780 /* Pass the function the address in which to return a structure value. */
3781 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
3783 emit_move_insn (struct_value
,
3785 force_operand (XEXP (mem_value
, 0),
3787 if (REG_P (struct_value
))
3788 use_reg (&call_fusage
, struct_value
);
3791 /* Don't allow popping to be deferred, since then
3792 cse'ing of library calls could delete a call and leave the pop. */
3794 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
3795 ? hard_libcall_value (outmode
) : NULL_RTX
);
3797 /* Stack must be properly aligned now. */
3798 gcc_assert (!(stack_pointer_delta
3799 & (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1)));
3801 before_call
= get_last_insn ();
3803 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3804 will set inhibit_defer_pop to that value. */
3805 /* The return type is needed to decide how many bytes the function pops.
3806 Signedness plays no role in that, so for simplicity, we pretend it's
3807 always signed. We also assume that the list of arguments passed has
3808 no impact, so we pretend it is unknown. */
3810 emit_call_1 (fun
, NULL
,
3811 get_identifier (XSTR (orgfun
, 0)),
3812 build_function_type (tfom
, NULL_TREE
),
3813 original_args_size
.constant
, args_size
.constant
,
3815 FUNCTION_ARG (args_so_far
, VOIDmode
, void_type_node
, 1),
3817 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, & args_so_far
);
3819 /* For calls to `setjmp', etc., inform flow.c it should complain
3820 if nonvolatile values are live. For functions that cannot return,
3821 inform flow that control does not fall through. */
3823 if (flags
& ECF_NORETURN
)
3825 /* The barrier note must be emitted
3826 immediately after the CALL_INSN. Some ports emit more than
3827 just a CALL_INSN above, so we must search for it here. */
3829 rtx last
= get_last_insn ();
3830 while (!CALL_P (last
))
3832 last
= PREV_INSN (last
);
3833 /* There was no CALL_INSN? */
3834 gcc_assert (last
!= before_call
);
3837 emit_barrier_after (last
);
3840 /* Now restore inhibit_defer_pop to its actual original value. */
3843 /* If call is cse'able, make appropriate pair of reg-notes around it.
3844 Test valreg so we don't crash; may safely ignore `const'
3845 if return type is void. Disable for PARALLEL return values, because
3846 we have no way to move such values into a pseudo register. */
3847 if (flags
& ECF_LIBCALL_BLOCK
)
3853 insns
= get_insns ();
3863 if (GET_CODE (valreg
) == PARALLEL
)
3865 temp
= gen_reg_rtx (outmode
);
3866 emit_group_store (temp
, valreg
, NULL_TREE
,
3867 GET_MODE_SIZE (outmode
));
3871 temp
= gen_reg_rtx (GET_MODE (valreg
));
3873 /* Construct an "equal form" for the value which mentions all the
3874 arguments in order as well as the function name. */
3875 for (i
= 0; i
< nargs
; i
++)
3876 note
= gen_rtx_EXPR_LIST (VOIDmode
, argvec
[i
].value
, note
);
3877 note
= gen_rtx_EXPR_LIST (VOIDmode
, fun
, note
);
3879 insns
= get_insns ();
3882 if (flags
& ECF_PURE
)
3883 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3884 gen_rtx_USE (VOIDmode
,
3885 gen_rtx_MEM (BLKmode
,
3886 gen_rtx_SCRATCH (VOIDmode
))),
3889 emit_libcall_block (insns
, temp
, valreg
, note
);
3896 /* Copy the value to the right place. */
3897 if (outmode
!= VOIDmode
&& retval
)
3903 if (value
!= mem_value
)
3904 emit_move_insn (value
, mem_value
);
3906 else if (GET_CODE (valreg
) == PARALLEL
)
3909 value
= gen_reg_rtx (outmode
);
3910 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
3914 /* Convert to the proper mode if PROMOTE_MODE has been active. */
3915 if (GET_MODE (valreg
) != outmode
)
3917 int unsignedp
= TYPE_UNSIGNED (tfom
);
3919 gcc_assert (targetm
.calls
.promote_function_return (tfom
));
3920 gcc_assert (promote_mode (tfom
, outmode
, &unsignedp
, 0)
3921 == GET_MODE (valreg
));
3923 valreg
= convert_modes (outmode
, GET_MODE (valreg
), valreg
, 0);
3927 emit_move_insn (value
, valreg
);
3933 if (ACCUMULATE_OUTGOING_ARGS
)
3935 #ifdef REG_PARM_STACK_SPACE
3937 restore_fixed_argument_area (save_area
, argblock
,
3938 high_to_save
, low_to_save
);
3941 /* If we saved any argument areas, restore them. */
3942 for (count
= 0; count
< nargs
; count
++)
3943 if (argvec
[count
].save_area
)
3945 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
3946 rtx adr
= plus_constant (argblock
,
3947 argvec
[count
].locate
.offset
.constant
);
3948 rtx stack_area
= gen_rtx_MEM (save_mode
,
3949 memory_address (save_mode
, adr
));
3951 if (save_mode
== BLKmode
)
3952 emit_block_move (stack_area
,
3953 validize_mem (argvec
[count
].save_area
),
3954 GEN_INT (argvec
[count
].locate
.size
.constant
),
3955 BLOCK_OP_CALL_PARM
);
3957 emit_move_insn (stack_area
, argvec
[count
].save_area
);
3960 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3961 stack_usage_map
= initial_stack_usage_map
;
3964 if (stack_usage_map_buf
)
3965 free (stack_usage_map_buf
);
3971 /* Output a library call to function FUN (a SYMBOL_REF rtx)
3972 (emitting the queue unless NO_QUEUE is nonzero),
3973 for a value of mode OUTMODE,
3974 with NARGS different arguments, passed as alternating rtx values
3975 and machine_modes to convert them to.
3977 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
3978 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
3979 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
3980 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
3981 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
3982 or other LCT_ value for other types of library calls. */
3985 emit_library_call (rtx orgfun
, enum libcall_type fn_type
,
3986 enum machine_mode outmode
, int nargs
, ...)
3990 va_start (p
, nargs
);
3991 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
3995 /* Like emit_library_call except that an extra argument, VALUE,
3996 comes second and says where to store the result.
3997 (If VALUE is zero, this function chooses a convenient way
3998 to return the value.
4000 This function returns an rtx for where the value is to be found.
4001 If VALUE is nonzero, VALUE is returned. */
4004 emit_library_call_value (rtx orgfun
, rtx value
,
4005 enum libcall_type fn_type
,
4006 enum machine_mode outmode
, int nargs
, ...)
4011 va_start (p
, nargs
);
4012 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
4019 /* Store a single argument for a function call
4020 into the register or memory area where it must be passed.
4021 *ARG describes the argument value and where to pass it.
4023 ARGBLOCK is the address of the stack-block for all the arguments,
4024 or 0 on a machine where arguments are pushed individually.
4026 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4027 so must be careful about how the stack is used.
4029 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4030 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4031 that we need not worry about saving and restoring the stack.
4033 FNDECL is the declaration of the function we are calling.
4035 Return nonzero if this arg should cause sibcall failure,
4039 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
4040 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
4042 tree pval
= arg
->tree_value
;
4046 int i
, lower_bound
= 0, upper_bound
= 0;
4047 int sibcall_failure
= 0;
4049 if (TREE_CODE (pval
) == ERROR_MARK
)
4052 /* Push a new temporary level for any temporaries we make for
4056 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4058 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4059 save any previous data at that location. */
4060 if (argblock
&& ! variable_size
&& arg
->stack
)
4062 #ifdef ARGS_GROW_DOWNWARD
4063 /* stack_slot is negative, but we want to index stack_usage_map
4064 with positive values. */
4065 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4066 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4070 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
4072 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4073 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4077 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
4081 /* Don't worry about things in the fixed argument area;
4082 it has already been saved. */
4083 if (i
< reg_parm_stack_space
)
4084 i
= reg_parm_stack_space
;
4085 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
4088 if (i
< upper_bound
)
4090 /* We need to make a save area. */
4091 unsigned int size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
4092 enum machine_mode save_mode
= mode_for_size (size
, MODE_INT
, 1);
4093 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
4094 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
4096 if (save_mode
== BLKmode
)
4098 tree ot
= TREE_TYPE (arg
->tree_value
);
4099 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4100 | TYPE_QUAL_CONST
));
4102 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4103 preserve_temp_slots (arg
->save_area
);
4104 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4105 GEN_INT (arg
->locate
.size
.constant
),
4106 BLOCK_OP_CALL_PARM
);
4110 arg
->save_area
= gen_reg_rtx (save_mode
);
4111 emit_move_insn (arg
->save_area
, stack_area
);
4117 /* If this isn't going to be placed on both the stack and in registers,
4118 set up the register and number of words. */
4119 if (! arg
->pass_on_stack
)
4121 if (flags
& ECF_SIBCALL
)
4122 reg
= arg
->tail_call_reg
;
4125 partial
= arg
->partial
;
4128 /* Being passed entirely in a register. We shouldn't be called in
4130 gcc_assert (reg
== 0 || partial
!= 0);
4132 /* If this arg needs special alignment, don't load the registers
4134 if (arg
->n_aligned_regs
!= 0)
4137 /* If this is being passed partially in a register, we can't evaluate
4138 it directly into its stack slot. Otherwise, we can. */
4139 if (arg
->value
== 0)
4141 /* stack_arg_under_construction is nonzero if a function argument is
4142 being evaluated directly into the outgoing argument list and
4143 expand_call must take special action to preserve the argument list
4144 if it is called recursively.
4146 For scalar function arguments stack_usage_map is sufficient to
4147 determine which stack slots must be saved and restored. Scalar
4148 arguments in general have pass_on_stack == 0.
4150 If this argument is initialized by a function which takes the
4151 address of the argument (a C++ constructor or a C function
4152 returning a BLKmode structure), then stack_usage_map is
4153 insufficient and expand_call must push the stack around the
4154 function call. Such arguments have pass_on_stack == 1.
4156 Note that it is always safe to set stack_arg_under_construction,
4157 but this generates suboptimal code if set when not needed. */
4159 if (arg
->pass_on_stack
)
4160 stack_arg_under_construction
++;
4162 arg
->value
= expand_expr (pval
,
4164 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4165 ? NULL_RTX
: arg
->stack
,
4166 VOIDmode
, EXPAND_STACK_PARM
);
4168 /* If we are promoting object (or for any other reason) the mode
4169 doesn't agree, convert the mode. */
4171 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4172 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4173 arg
->value
, arg
->unsignedp
);
4175 if (arg
->pass_on_stack
)
4176 stack_arg_under_construction
--;
4179 /* Check for overlap with already clobbered argument area. */
4180 if ((flags
& ECF_SIBCALL
)
4181 && MEM_P (arg
->value
)
4182 && mem_overlaps_already_clobbered_arg_p (XEXP (arg
->value
, 0),
4183 arg
->locate
.size
.constant
))
4184 sibcall_failure
= 1;
4186 /* Don't allow anything left on stack from computation
4187 of argument to alloca. */
4188 if (flags
& ECF_MAY_BE_ALLOCA
)
4189 do_pending_stack_adjust ();
4191 if (arg
->value
== arg
->stack
)
4192 /* If the value is already in the stack slot, we are done. */
4194 else if (arg
->mode
!= BLKmode
)
4197 unsigned int parm_align
;
4199 /* Argument is a scalar, not entirely passed in registers.
4200 (If part is passed in registers, arg->partial says how much
4201 and emit_push_insn will take care of putting it there.)
4203 Push it, and if its size is less than the
4204 amount of space allocated to it,
4205 also bump stack pointer by the additional space.
4206 Note that in C the default argument promotions
4207 will prevent such mismatches. */
4209 size
= GET_MODE_SIZE (arg
->mode
);
4210 /* Compute how much space the push instruction will push.
4211 On many machines, pushing a byte will advance the stack
4212 pointer by a halfword. */
4213 #ifdef PUSH_ROUNDING
4214 size
= PUSH_ROUNDING (size
);
4218 /* Compute how much space the argument should get:
4219 round up to a multiple of the alignment for arguments. */
4220 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4221 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4222 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4223 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4225 /* Compute the alignment of the pushed argument. */
4226 parm_align
= arg
->locate
.boundary
;
4227 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4229 int pad
= used
- size
;
4232 unsigned int pad_align
= (pad
& -pad
) * BITS_PER_UNIT
;
4233 parm_align
= MIN (parm_align
, pad_align
);
4237 /* This isn't already where we want it on the stack, so put it there.
4238 This can either be done with push or copy insns. */
4239 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
,
4240 parm_align
, partial
, reg
, used
- size
, argblock
,
4241 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4242 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4244 /* Unless this is a partially-in-register argument, the argument is now
4247 arg
->value
= arg
->stack
;
4251 /* BLKmode, at least partly to be pushed. */
4253 unsigned int parm_align
;
4257 /* Pushing a nonscalar.
4258 If part is passed in registers, PARTIAL says how much
4259 and emit_push_insn will take care of putting it there. */
4261 /* Round its size up to a multiple
4262 of the allocation unit for arguments. */
4264 if (arg
->locate
.size
.var
!= 0)
4267 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
4271 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4272 for BLKmode is careful to avoid it. */
4273 excess
= (arg
->locate
.size
.constant
4274 - int_size_in_bytes (TREE_TYPE (pval
))
4276 size_rtx
= expand_expr (size_in_bytes (TREE_TYPE (pval
)),
4277 NULL_RTX
, TYPE_MODE (sizetype
), 0);
4280 parm_align
= arg
->locate
.boundary
;
4282 /* When an argument is padded down, the block is aligned to
4283 PARM_BOUNDARY, but the actual argument isn't. */
4284 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4286 if (arg
->locate
.size
.var
)
4287 parm_align
= BITS_PER_UNIT
;
4290 unsigned int excess_align
= (excess
& -excess
) * BITS_PER_UNIT
;
4291 parm_align
= MIN (parm_align
, excess_align
);
4295 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
4297 /* emit_push_insn might not work properly if arg->value and
4298 argblock + arg->locate.offset areas overlap. */
4302 if (XEXP (x
, 0) == current_function_internal_arg_pointer
4303 || (GET_CODE (XEXP (x
, 0)) == PLUS
4304 && XEXP (XEXP (x
, 0), 0) ==
4305 current_function_internal_arg_pointer
4306 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
))
4308 if (XEXP (x
, 0) != current_function_internal_arg_pointer
)
4309 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4311 /* expand_call should ensure this. */
4312 gcc_assert (!arg
->locate
.offset
.var
4313 && GET_CODE (size_rtx
) == CONST_INT
);
4315 if (arg
->locate
.offset
.constant
> i
)
4317 if (arg
->locate
.offset
.constant
< i
+ INTVAL (size_rtx
))
4318 sibcall_failure
= 1;
4320 else if (arg
->locate
.offset
.constant
< i
)
4322 if (i
< arg
->locate
.offset
.constant
+ INTVAL (size_rtx
))
4323 sibcall_failure
= 1;
4328 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4329 parm_align
, partial
, reg
, excess
, argblock
,
4330 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4331 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4333 /* Unless this is a partially-in-register argument, the argument is now
4336 ??? Unlike the case above, in which we want the actual
4337 address of the data, so that we can load it directly into a
4338 register, here we want the address of the stack slot, so that
4339 it's properly aligned for word-by-word copying or something
4340 like that. It's not clear that this is always correct. */
4342 arg
->value
= arg
->stack_slot
;
4345 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
4347 tree type
= TREE_TYPE (arg
->tree_value
);
4349 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
4350 int_size_in_bytes (type
));
4353 /* Mark all slots this store used. */
4354 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
4355 && argblock
&& ! variable_size
&& arg
->stack
)
4356 for (i
= lower_bound
; i
< upper_bound
; i
++)
4357 stack_usage_map
[i
] = 1;
4359 /* Once we have pushed something, pops can't safely
4360 be deferred during the rest of the arguments. */
4363 /* Free any temporary slots made in processing this argument. Show
4364 that we might have taken the address of something and pushed that
4366 preserve_temp_slots (NULL_RTX
);
4370 return sibcall_failure
;
4373 /* Nonzero if we do not know how to pass TYPE solely in registers. */
4376 must_pass_in_stack_var_size (enum machine_mode mode ATTRIBUTE_UNUSED
,
4382 /* If the type has variable size... */
4383 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4386 /* If the type is marked as addressable (it is required
4387 to be constructed into the stack)... */
4388 if (TREE_ADDRESSABLE (type
))
4394 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
4395 takes trailing padding of a structure into account. */
4396 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
4399 must_pass_in_stack_var_size_or_pad (enum machine_mode mode
, tree type
)
4404 /* If the type has variable size... */
4405 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4408 /* If the type is marked as addressable (it is required
4409 to be constructed into the stack)... */
4410 if (TREE_ADDRESSABLE (type
))
4413 /* If the padding and mode of the type is such that a copy into
4414 a register would put it into the wrong part of the register. */
4416 && int_size_in_bytes (type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
4417 && (FUNCTION_ARG_PADDING (mode
, type
)
4418 == (BYTES_BIG_ENDIAN
? upward
: downward
)))