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
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, tree
,
136 tree
, CUMULATIVE_ARGS
*, int,
137 rtx
*, int *, int *, int *,
139 static void compute_argument_addresses (struct arg_data
*, rtx
, int);
140 static rtx
rtx_for_function_call (tree
, tree
);
141 static void load_register_parameters (struct arg_data
*, int, rtx
*, int,
143 static rtx
emit_library_call_value_1 (int, rtx
, rtx
, enum libcall_type
,
144 enum machine_mode
, int, va_list);
145 static int special_function_p (tree
, int);
146 static int check_sibcall_argument_overlap_1 (rtx
);
147 static int check_sibcall_argument_overlap (rtx
, struct arg_data
*, int);
149 static int combine_pending_stack_adjustment_and_call (int, struct args_size
*,
151 static tree
split_complex_values (tree
);
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 (TREE_OPERAND (exp
, 0)) == ADDR_EXPR
557 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0))
559 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0),
560 0) & ECF_MAY_BE_ALLOCA
))
565 /* Detect flags (function attributes) from the function decl or type node. */
568 flags_from_decl_or_type (tree exp
)
575 type
= TREE_TYPE (exp
);
577 /* The function exp may have the `malloc' attribute. */
578 if (DECL_IS_MALLOC (exp
))
581 /* The function exp may have the `returns_twice' attribute. */
582 if (DECL_IS_RETURNS_TWICE (exp
))
583 flags
|= ECF_RETURNS_TWICE
;
585 /* The function exp may have the `pure' attribute. */
586 if (DECL_IS_PURE (exp
))
589 if (DECL_IS_NOVOPS (exp
))
592 if (TREE_NOTHROW (exp
))
593 flags
|= ECF_NOTHROW
;
595 if (TREE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
598 flags
= special_function_p (exp
, flags
);
600 else if (TYPE_P (exp
) && TYPE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
603 if (TREE_THIS_VOLATILE (exp
))
604 flags
|= ECF_NORETURN
;
606 /* Mark if the function returns with the stack pointer depressed. We
607 cannot consider it pure or constant in that case. */
608 if (TREE_CODE (type
) == FUNCTION_TYPE
&& TYPE_RETURNS_STACK_DEPRESSED (type
))
610 flags
|= ECF_SP_DEPRESSED
;
611 flags
&= ~(ECF_PURE
| ECF_CONST
);
617 /* Detect flags from a CALL_EXPR. */
620 call_expr_flags (tree t
)
623 tree decl
= get_callee_fndecl (t
);
626 flags
= flags_from_decl_or_type (decl
);
629 t
= TREE_TYPE (TREE_OPERAND (t
, 0));
630 if (t
&& TREE_CODE (t
) == POINTER_TYPE
)
631 flags
= flags_from_decl_or_type (TREE_TYPE (t
));
639 /* Precompute all register parameters as described by ARGS, storing values
640 into fields within the ARGS array.
642 NUM_ACTUALS indicates the total number elements in the ARGS array.
644 Set REG_PARM_SEEN if we encounter a register parameter. */
647 precompute_register_parameters (int num_actuals
, struct arg_data
*args
,
654 for (i
= 0; i
< num_actuals
; i
++)
655 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
659 if (args
[i
].value
== 0)
662 args
[i
].value
= expand_normal (args
[i
].tree_value
);
663 preserve_temp_slots (args
[i
].value
);
667 /* If the value is a non-legitimate constant, force it into a
668 pseudo now. TLS symbols sometimes need a call to resolve. */
669 if (CONSTANT_P (args
[i
].value
)
670 && !LEGITIMATE_CONSTANT_P (args
[i
].value
))
671 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
673 /* If we are to promote the function arg to a wider mode,
676 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
678 = convert_modes (args
[i
].mode
,
679 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
680 args
[i
].value
, args
[i
].unsignedp
);
682 /* If we're going to have to load the value by parts, pull the
683 parts into pseudos. The part extraction process can involve
684 non-trivial computation. */
685 if (GET_CODE (args
[i
].reg
) == PARALLEL
)
687 tree type
= TREE_TYPE (args
[i
].tree_value
);
688 args
[i
].parallel_value
689 = emit_group_load_into_temps (args
[i
].reg
, args
[i
].value
,
690 type
, int_size_in_bytes (type
));
693 /* If the value is expensive, and we are inside an appropriately
694 short loop, put the value into a pseudo and then put the pseudo
697 For small register classes, also do this if this call uses
698 register parameters. This is to avoid reload conflicts while
699 loading the parameters registers. */
701 else if ((! (REG_P (args
[i
].value
)
702 || (GET_CODE (args
[i
].value
) == SUBREG
703 && REG_P (SUBREG_REG (args
[i
].value
)))))
704 && args
[i
].mode
!= BLKmode
705 && rtx_cost (args
[i
].value
, SET
) > COSTS_N_INSNS (1)
706 && ((SMALL_REGISTER_CLASSES
&& *reg_parm_seen
)
708 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
712 #ifdef REG_PARM_STACK_SPACE
714 /* The argument list is the property of the called routine and it
715 may clobber it. If the fixed area has been used for previous
716 parameters, we must save and restore it. */
719 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
724 /* Compute the boundary of the area that needs to be saved, if any. */
725 high
= reg_parm_stack_space
;
726 #ifdef ARGS_GROW_DOWNWARD
729 if (high
> highest_outgoing_arg_in_use
)
730 high
= highest_outgoing_arg_in_use
;
732 for (low
= 0; low
< high
; low
++)
733 if (stack_usage_map
[low
] != 0)
736 enum machine_mode save_mode
;
741 while (stack_usage_map
[--high
] == 0)
745 *high_to_save
= high
;
747 num_to_save
= high
- low
+ 1;
748 save_mode
= mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
750 /* If we don't have the required alignment, must do this
752 if ((low
& (MIN (GET_MODE_SIZE (save_mode
),
753 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
756 #ifdef ARGS_GROW_DOWNWARD
761 stack_area
= gen_rtx_MEM (save_mode
,
762 memory_address (save_mode
,
763 plus_constant (argblock
,
766 set_mem_align (stack_area
, PARM_BOUNDARY
);
767 if (save_mode
== BLKmode
)
769 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
770 emit_block_move (validize_mem (save_area
), stack_area
,
771 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
775 save_area
= gen_reg_rtx (save_mode
);
776 emit_move_insn (save_area
, stack_area
);
786 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
788 enum machine_mode save_mode
= GET_MODE (save_area
);
792 #ifdef ARGS_GROW_DOWNWARD
793 delta
= -high_to_save
;
797 stack_area
= gen_rtx_MEM (save_mode
,
798 memory_address (save_mode
,
799 plus_constant (argblock
, delta
)));
800 set_mem_align (stack_area
, PARM_BOUNDARY
);
802 if (save_mode
!= BLKmode
)
803 emit_move_insn (stack_area
, save_area
);
805 emit_block_move (stack_area
, validize_mem (save_area
),
806 GEN_INT (high_to_save
- low_to_save
+ 1),
809 #endif /* REG_PARM_STACK_SPACE */
811 /* If any elements in ARGS refer to parameters that are to be passed in
812 registers, but not in memory, and whose alignment does not permit a
813 direct copy into registers. Copy the values into a group of pseudos
814 which we will later copy into the appropriate hard registers.
816 Pseudos for each unaligned argument will be stored into the array
817 args[argnum].aligned_regs. The caller is responsible for deallocating
818 the aligned_regs array if it is nonzero. */
821 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
825 for (i
= 0; i
< num_actuals
; i
++)
826 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
827 && args
[i
].mode
== BLKmode
828 && (TYPE_ALIGN (TREE_TYPE (args
[i
].tree_value
))
829 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
831 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
832 int endian_correction
= 0;
836 gcc_assert (args
[i
].partial
% UNITS_PER_WORD
== 0);
837 args
[i
].n_aligned_regs
= args
[i
].partial
/ UNITS_PER_WORD
;
841 args
[i
].n_aligned_regs
842 = (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
845 args
[i
].aligned_regs
= XNEWVEC (rtx
, args
[i
].n_aligned_regs
);
847 /* Structures smaller than a word are normally aligned to the
848 least significant byte. On a BYTES_BIG_ENDIAN machine,
849 this means we must skip the empty high order bytes when
850 calculating the bit offset. */
851 if (bytes
< UNITS_PER_WORD
852 #ifdef BLOCK_REG_PADDING
853 && (BLOCK_REG_PADDING (args
[i
].mode
,
854 TREE_TYPE (args
[i
].tree_value
), 1)
860 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
862 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
864 rtx reg
= gen_reg_rtx (word_mode
);
865 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
866 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
868 args
[i
].aligned_regs
[j
] = reg
;
869 word
= extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
870 word_mode
, word_mode
);
872 /* There is no need to restrict this code to loading items
873 in TYPE_ALIGN sized hunks. The bitfield instructions can
874 load up entire word sized registers efficiently.
876 ??? This may not be needed anymore.
877 We use to emit a clobber here but that doesn't let later
878 passes optimize the instructions we emit. By storing 0 into
879 the register later passes know the first AND to zero out the
880 bitfield being set in the register is unnecessary. The store
881 of 0 will be deleted as will at least the first AND. */
883 emit_move_insn (reg
, const0_rtx
);
885 bytes
-= bitsize
/ BITS_PER_UNIT
;
886 store_bit_field (reg
, bitsize
, endian_correction
, word_mode
,
892 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
895 NUM_ACTUALS is the total number of parameters.
897 N_NAMED_ARGS is the total number of named arguments.
899 FNDECL is the tree code for the target of this call (if known)
901 ARGS_SO_FAR holds state needed by the target to know where to place
904 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
905 for arguments which are passed in registers.
907 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
908 and may be modified by this routine.
910 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
911 flags which may may be modified by this routine.
913 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
914 that requires allocation of stack space.
916 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
917 the thunked-to function. */
920 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
921 struct arg_data
*args
,
922 struct args_size
*args_size
,
923 int n_named_args ATTRIBUTE_UNUSED
,
924 tree actparms
, tree fndecl
,
925 CUMULATIVE_ARGS
*args_so_far
,
926 int reg_parm_stack_space
,
927 rtx
*old_stack_level
, int *old_pending_adj
,
928 int *must_preallocate
, int *ecf_flags
,
929 bool *may_tailcall
, bool call_from_thunk_p
)
931 /* 1 if scanning parms front to back, -1 if scanning back to front. */
934 /* Count arg position in order args appear. */
940 args_size
->constant
= 0;
943 /* In this loop, we consider args in the order they are written.
944 We fill up ARGS from the front or from the back if necessary
945 so that in any case the first arg to be pushed ends up at the front. */
947 if (PUSH_ARGS_REVERSED
)
949 i
= num_actuals
- 1, inc
= -1;
950 /* In this case, must reverse order of args
951 so that we compute and push the last arg first. */
958 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
959 for (p
= actparms
, argpos
= 0; p
; p
= TREE_CHAIN (p
), i
+= inc
, argpos
++)
961 tree type
= TREE_TYPE (TREE_VALUE (p
));
963 enum machine_mode mode
;
965 args
[i
].tree_value
= TREE_VALUE (p
);
967 /* Replace erroneous argument with constant zero. */
968 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
969 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
971 /* If TYPE is a transparent union, pass things the way we would
972 pass the first field of the union. We have already verified that
973 the modes are the same. */
974 if (TREE_CODE (type
) == UNION_TYPE
&& TYPE_TRANSPARENT_UNION (type
))
975 type
= TREE_TYPE (TYPE_FIELDS (type
));
977 /* Decide where to pass this arg.
979 args[i].reg is nonzero if all or part is passed in registers.
981 args[i].partial is nonzero if part but not all is passed in registers,
982 and the exact value says how many bytes are passed in registers.
984 args[i].pass_on_stack is nonzero if the argument must at least be
985 computed on the stack. It may then be loaded back into registers
986 if args[i].reg is nonzero.
988 These decisions are driven by the FUNCTION_... macros and must agree
989 with those made by function.c. */
991 /* See if this argument should be passed by invisible reference. */
992 if (pass_by_reference (args_so_far
, TYPE_MODE (type
),
993 type
, argpos
< n_named_args
))
999 = reference_callee_copied (args_so_far
, TYPE_MODE (type
),
1000 type
, argpos
< n_named_args
);
1002 /* If we're compiling a thunk, pass through invisible references
1003 instead of making a copy. */
1004 if (call_from_thunk_p
1006 && !TREE_ADDRESSABLE (type
)
1007 && (base
= get_base_address (args
[i
].tree_value
))
1008 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
)))))
1010 /* We can't use sibcalls if a callee-copied argument is
1011 stored in the current function's frame. */
1012 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
1013 *may_tailcall
= false;
1015 args
[i
].tree_value
= build_fold_addr_expr (args
[i
].tree_value
);
1016 type
= TREE_TYPE (args
[i
].tree_value
);
1018 *ecf_flags
&= ~(ECF_CONST
| ECF_LIBCALL_BLOCK
);
1022 /* We make a copy of the object and pass the address to the
1023 function being called. */
1026 if (!COMPLETE_TYPE_P (type
)
1027 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1028 || (flag_stack_check
&& ! STACK_CHECK_BUILTIN
1029 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type
),
1030 STACK_CHECK_MAX_VAR_SIZE
))))
1032 /* This is a variable-sized object. Make space on the stack
1034 rtx size_rtx
= expr_size (TREE_VALUE (p
));
1036 if (*old_stack_level
== 0)
1038 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1039 *old_pending_adj
= pending_stack_adjust
;
1040 pending_stack_adjust
= 0;
1043 copy
= gen_rtx_MEM (BLKmode
,
1044 allocate_dynamic_stack_space
1045 (size_rtx
, NULL_RTX
, TYPE_ALIGN (type
)));
1046 set_mem_attributes (copy
, type
, 1);
1049 copy
= assign_temp (type
, 0, 1, 0);
1051 store_expr (args
[i
].tree_value
, copy
, 0);
1054 *ecf_flags
&= ~(ECF_CONST
| ECF_LIBCALL_BLOCK
);
1056 *ecf_flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
1059 = build_fold_addr_expr (make_tree (type
, copy
));
1060 type
= TREE_TYPE (args
[i
].tree_value
);
1061 *may_tailcall
= false;
1065 mode
= TYPE_MODE (type
);
1066 unsignedp
= TYPE_UNSIGNED (type
);
1068 if (targetm
.calls
.promote_function_args (fndecl
? TREE_TYPE (fndecl
) : 0))
1069 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
1071 args
[i
].unsignedp
= unsignedp
;
1072 args
[i
].mode
= mode
;
1074 args
[i
].reg
= FUNCTION_ARG (*args_so_far
, mode
, type
,
1075 argpos
< n_named_args
);
1076 #ifdef FUNCTION_INCOMING_ARG
1077 /* If this is a sibling call and the machine has register windows, the
1078 register window has to be unwinded before calling the routine, so
1079 arguments have to go into the incoming registers. */
1080 args
[i
].tail_call_reg
= FUNCTION_INCOMING_ARG (*args_so_far
, mode
, type
,
1081 argpos
< n_named_args
);
1083 args
[i
].tail_call_reg
= args
[i
].reg
;
1088 = targetm
.calls
.arg_partial_bytes (args_so_far
, mode
, type
,
1089 argpos
< n_named_args
);
1091 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (mode
, type
);
1093 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1094 it means that we are to pass this arg in the register(s) designated
1095 by the PARALLEL, but also to pass it in the stack. */
1096 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1097 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1098 args
[i
].pass_on_stack
= 1;
1100 /* If this is an addressable type, we must preallocate the stack
1101 since we must evaluate the object into its final location.
1103 If this is to be passed in both registers and the stack, it is simpler
1105 if (TREE_ADDRESSABLE (type
)
1106 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1107 *must_preallocate
= 1;
1109 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1110 we cannot consider this function call constant. */
1111 if (TREE_ADDRESSABLE (type
))
1112 *ecf_flags
&= ~ECF_LIBCALL_BLOCK
;
1114 /* Compute the stack-size of this argument. */
1115 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1116 || reg_parm_stack_space
> 0
1117 || args
[i
].pass_on_stack
)
1118 locate_and_pad_parm (mode
, type
,
1119 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1124 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
1125 fndecl
, args_size
, &args
[i
].locate
);
1126 #ifdef BLOCK_REG_PADDING
1128 /* The argument is passed entirely in registers. See at which
1129 end it should be padded. */
1130 args
[i
].locate
.where_pad
=
1131 BLOCK_REG_PADDING (mode
, type
,
1132 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
1135 /* Update ARGS_SIZE, the total stack space for args so far. */
1137 args_size
->constant
+= args
[i
].locate
.size
.constant
;
1138 if (args
[i
].locate
.size
.var
)
1139 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
1141 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1142 have been used, etc. */
1144 FUNCTION_ARG_ADVANCE (*args_so_far
, TYPE_MODE (type
), type
,
1145 argpos
< n_named_args
);
1149 /* Update ARGS_SIZE to contain the total size for the argument block.
1150 Return the original constant component of the argument block's size.
1152 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1153 for arguments passed in registers. */
1156 compute_argument_block_size (int reg_parm_stack_space
,
1157 struct args_size
*args_size
,
1158 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
1160 int unadjusted_args_size
= args_size
->constant
;
1162 /* For accumulate outgoing args mode we don't need to align, since the frame
1163 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1164 backends from generating misaligned frame sizes. */
1165 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1166 preferred_stack_boundary
= STACK_BOUNDARY
;
1168 /* Compute the actual size of the argument block required. The variable
1169 and constant sizes must be combined, the size may have to be rounded,
1170 and there may be a minimum required size. */
1174 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1175 args_size
->constant
= 0;
1177 preferred_stack_boundary
/= BITS_PER_UNIT
;
1178 if (preferred_stack_boundary
> 1)
1180 /* We don't handle this case yet. To handle it correctly we have
1181 to add the delta, round and subtract the delta.
1182 Currently no machine description requires this support. */
1183 gcc_assert (!(stack_pointer_delta
& (preferred_stack_boundary
- 1)));
1184 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1187 if (reg_parm_stack_space
> 0)
1190 = size_binop (MAX_EXPR
, args_size
->var
,
1191 ssize_int (reg_parm_stack_space
));
1193 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1194 /* The area corresponding to register parameters is not to count in
1195 the size of the block we need. So make the adjustment. */
1197 = size_binop (MINUS_EXPR
, args_size
->var
,
1198 ssize_int (reg_parm_stack_space
));
1204 preferred_stack_boundary
/= BITS_PER_UNIT
;
1205 if (preferred_stack_boundary
< 1)
1206 preferred_stack_boundary
= 1;
1207 args_size
->constant
= (((args_size
->constant
1208 + stack_pointer_delta
1209 + preferred_stack_boundary
- 1)
1210 / preferred_stack_boundary
1211 * preferred_stack_boundary
)
1212 - stack_pointer_delta
);
1214 args_size
->constant
= MAX (args_size
->constant
,
1215 reg_parm_stack_space
);
1217 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1218 args_size
->constant
-= reg_parm_stack_space
;
1221 return unadjusted_args_size
;
1224 /* Precompute parameters as needed for a function call.
1226 FLAGS is mask of ECF_* constants.
1228 NUM_ACTUALS is the number of arguments.
1230 ARGS is an array containing information for each argument; this
1231 routine fills in the INITIAL_VALUE and VALUE fields for each
1232 precomputed argument. */
1235 precompute_arguments (int flags
, int num_actuals
, struct arg_data
*args
)
1239 /* If this is a libcall, then precompute all arguments so that we do not
1240 get extraneous instructions emitted as part of the libcall sequence. */
1241 if ((flags
& ECF_LIBCALL_BLOCK
) == 0)
1244 for (i
= 0; i
< num_actuals
; i
++)
1246 enum machine_mode mode
;
1248 /* If this is an addressable type, we cannot pre-evaluate it. */
1249 gcc_assert (!TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
)));
1251 args
[i
].initial_value
= args
[i
].value
1252 = expand_normal (args
[i
].tree_value
);
1254 mode
= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
));
1255 if (mode
!= args
[i
].mode
)
1258 = convert_modes (args
[i
].mode
, mode
,
1259 args
[i
].value
, args
[i
].unsignedp
);
1260 #if defined(PROMOTE_FUNCTION_MODE) && !defined(PROMOTE_MODE)
1261 /* CSE will replace this only if it contains args[i].value
1262 pseudo, so convert it down to the declared mode using
1264 if (REG_P (args
[i
].value
)
1265 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
)
1267 args
[i
].initial_value
1268 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1269 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1270 SUBREG_PROMOTED_UNSIGNED_SET (args
[i
].initial_value
,
1278 /* Given the current state of MUST_PREALLOCATE and information about
1279 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1280 compute and return the final value for MUST_PREALLOCATE. */
1283 finalize_must_preallocate (int must_preallocate
, int num_actuals
, struct arg_data
*args
, struct args_size
*args_size
)
1285 /* See if we have or want to preallocate stack space.
1287 If we would have to push a partially-in-regs parm
1288 before other stack parms, preallocate stack space instead.
1290 If the size of some parm is not a multiple of the required stack
1291 alignment, we must preallocate.
1293 If the total size of arguments that would otherwise create a copy in
1294 a temporary (such as a CALL) is more than half the total argument list
1295 size, preallocation is faster.
1297 Another reason to preallocate is if we have a machine (like the m88k)
1298 where stack alignment is required to be maintained between every
1299 pair of insns, not just when the call is made. However, we assume here
1300 that such machines either do not have push insns (and hence preallocation
1301 would occur anyway) or the problem is taken care of with
1304 if (! must_preallocate
)
1306 int partial_seen
= 0;
1307 int copy_to_evaluate_size
= 0;
1310 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1312 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1314 else if (partial_seen
&& args
[i
].reg
== 0)
1315 must_preallocate
= 1;
1317 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1318 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1319 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1320 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1321 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1322 copy_to_evaluate_size
1323 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1326 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1327 && args_size
->constant
> 0)
1328 must_preallocate
= 1;
1330 return must_preallocate
;
1333 /* If we preallocated stack space, compute the address of each argument
1334 and store it into the ARGS array.
1336 We need not ensure it is a valid memory address here; it will be
1337 validized when it is used.
1339 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1342 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
1346 rtx arg_reg
= argblock
;
1347 int i
, arg_offset
= 0;
1349 if (GET_CODE (argblock
) == PLUS
)
1350 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1352 for (i
= 0; i
< num_actuals
; i
++)
1354 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
1355 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
1357 unsigned int align
, boundary
;
1359 /* Skip this parm if it will not be passed on the stack. */
1360 if (! args
[i
].pass_on_stack
&& args
[i
].reg
!= 0)
1363 if (GET_CODE (offset
) == CONST_INT
)
1364 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1366 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1368 addr
= plus_constant (addr
, arg_offset
);
1369 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1370 set_mem_attributes (args
[i
].stack
,
1371 TREE_TYPE (args
[i
].tree_value
), 1);
1372 align
= BITS_PER_UNIT
;
1373 boundary
= args
[i
].locate
.boundary
;
1374 if (args
[i
].locate
.where_pad
!= downward
)
1376 else if (GET_CODE (offset
) == CONST_INT
)
1378 align
= INTVAL (offset
) * BITS_PER_UNIT
| boundary
;
1379 align
= align
& -align
;
1381 set_mem_align (args
[i
].stack
, align
);
1383 if (GET_CODE (slot_offset
) == CONST_INT
)
1384 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1386 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1388 addr
= plus_constant (addr
, arg_offset
);
1389 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1390 set_mem_attributes (args
[i
].stack_slot
,
1391 TREE_TYPE (args
[i
].tree_value
), 1);
1392 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
1394 /* Function incoming arguments may overlap with sibling call
1395 outgoing arguments and we cannot allow reordering of reads
1396 from function arguments with stores to outgoing arguments
1397 of sibling calls. */
1398 set_mem_alias_set (args
[i
].stack
, 0);
1399 set_mem_alias_set (args
[i
].stack_slot
, 0);
1404 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1405 in a call instruction.
1407 FNDECL is the tree node for the target function. For an indirect call
1408 FNDECL will be NULL_TREE.
1410 ADDR is the operand 0 of CALL_EXPR for this call. */
1413 rtx_for_function_call (tree fndecl
, tree addr
)
1417 /* Get the function to call, in the form of RTL. */
1420 /* If this is the first use of the function, see if we need to
1421 make an external definition for it. */
1422 if (! TREE_USED (fndecl
))
1424 assemble_external (fndecl
);
1425 TREE_USED (fndecl
) = 1;
1428 /* Get a SYMBOL_REF rtx for the function address. */
1429 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1432 /* Generate an rtx (probably a pseudo-register) for the address. */
1435 funexp
= expand_normal (addr
);
1436 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1441 /* Return true if and only if SIZE storage units (usually bytes)
1442 starting from address ADDR overlap with already clobbered argument
1443 area. This function is used to determine if we should give up a
1447 mem_overlaps_already_clobbered_arg_p (rtx addr
, unsigned HOST_WIDE_INT size
)
1451 if (addr
== current_function_internal_arg_pointer
)
1453 else if (GET_CODE (addr
) == PLUS
1455 == current_function_internal_arg_pointer
)
1456 && GET_CODE (XEXP (addr
, 1)) == CONST_INT
)
1457 i
= INTVAL (XEXP (addr
, 1));
1461 #ifdef ARGS_GROW_DOWNWARD
1466 unsigned HOST_WIDE_INT k
;
1468 for (k
= 0; k
< size
; k
++)
1469 if (i
+ k
< stored_args_map
->n_bits
1470 && TEST_BIT (stored_args_map
, i
+ k
))
1477 /* Do the register loads required for any wholly-register parms or any
1478 parms which are passed both on the stack and in a register. Their
1479 expressions were already evaluated.
1481 Mark all register-parms as living through the call, putting these USE
1482 insns in the CALL_INSN_FUNCTION_USAGE field.
1484 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1485 checking, setting *SIBCALL_FAILURE if appropriate. */
1488 load_register_parameters (struct arg_data
*args
, int num_actuals
,
1489 rtx
*call_fusage
, int flags
, int is_sibcall
,
1490 int *sibcall_failure
)
1494 for (i
= 0; i
< num_actuals
; i
++)
1496 rtx reg
= ((flags
& ECF_SIBCALL
)
1497 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1500 int partial
= args
[i
].partial
;
1503 rtx before_arg
= get_last_insn ();
1504 /* Set non-negative if we must move a word at a time, even if
1505 just one word (e.g, partial == 4 && mode == DFmode). Set
1506 to -1 if we just use a normal move insn. This value can be
1507 zero if the argument is a zero size structure. */
1509 if (GET_CODE (reg
) == PARALLEL
)
1513 gcc_assert (partial
% UNITS_PER_WORD
== 0);
1514 nregs
= partial
/ UNITS_PER_WORD
;
1516 else if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
)
1518 size
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1519 nregs
= (size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1522 size
= GET_MODE_SIZE (args
[i
].mode
);
1524 /* Handle calls that pass values in multiple non-contiguous
1525 locations. The Irix 6 ABI has examples of this. */
1527 if (GET_CODE (reg
) == PARALLEL
)
1528 emit_group_move (reg
, args
[i
].parallel_value
);
1530 /* If simple case, just do move. If normal partial, store_one_arg
1531 has already loaded the register for us. In all other cases,
1532 load the register(s) from memory. */
1534 else if (nregs
== -1)
1536 emit_move_insn (reg
, args
[i
].value
);
1537 #ifdef BLOCK_REG_PADDING
1538 /* Handle case where we have a value that needs shifting
1539 up to the msb. eg. a QImode value and we're padding
1540 upward on a BYTES_BIG_ENDIAN machine. */
1541 if (size
< UNITS_PER_WORD
1542 && (args
[i
].locate
.where_pad
1543 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
1546 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1548 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1549 report the whole reg as used. Strictly speaking, the
1550 call only uses SIZE bytes at the msb end, but it doesn't
1551 seem worth generating rtl to say that. */
1552 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
1553 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
1554 build_int_cst (NULL_TREE
, shift
),
1557 emit_move_insn (reg
, x
);
1562 /* If we have pre-computed the values to put in the registers in
1563 the case of non-aligned structures, copy them in now. */
1565 else if (args
[i
].n_aligned_regs
!= 0)
1566 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1567 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1568 args
[i
].aligned_regs
[j
]);
1570 else if (partial
== 0 || args
[i
].pass_on_stack
)
1572 rtx mem
= validize_mem (args
[i
].value
);
1574 /* Check for overlap with already clobbered argument area. */
1576 && mem_overlaps_already_clobbered_arg_p (XEXP (args
[i
].value
, 0),
1578 *sibcall_failure
= 1;
1580 /* Handle a BLKmode that needs shifting. */
1581 if (nregs
== 1 && size
< UNITS_PER_WORD
1582 #ifdef BLOCK_REG_PADDING
1583 && args
[i
].locate
.where_pad
== downward
1589 rtx tem
= operand_subword_force (mem
, 0, args
[i
].mode
);
1590 rtx ri
= gen_rtx_REG (word_mode
, REGNO (reg
));
1591 rtx x
= gen_reg_rtx (word_mode
);
1592 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1593 enum tree_code dir
= BYTES_BIG_ENDIAN
? RSHIFT_EXPR
1596 emit_move_insn (x
, tem
);
1597 x
= expand_shift (dir
, word_mode
, x
,
1598 build_int_cst (NULL_TREE
, shift
),
1601 emit_move_insn (ri
, x
);
1604 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
1607 /* When a parameter is a block, and perhaps in other cases, it is
1608 possible that it did a load from an argument slot that was
1609 already clobbered. */
1611 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
1612 *sibcall_failure
= 1;
1614 /* Handle calls that pass values in multiple non-contiguous
1615 locations. The Irix 6 ABI has examples of this. */
1616 if (GET_CODE (reg
) == PARALLEL
)
1617 use_group_regs (call_fusage
, reg
);
1618 else if (nregs
== -1)
1619 use_reg (call_fusage
, reg
);
1621 use_regs (call_fusage
, REGNO (reg
), nregs
);
1626 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1627 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1628 bytes, then we would need to push some additional bytes to pad the
1629 arguments. So, we compute an adjust to the stack pointer for an
1630 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1631 bytes. Then, when the arguments are pushed the stack will be perfectly
1632 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1633 be popped after the call. Returns the adjustment. */
1636 combine_pending_stack_adjustment_and_call (int unadjusted_args_size
,
1637 struct args_size
*args_size
,
1638 unsigned int preferred_unit_stack_boundary
)
1640 /* The number of bytes to pop so that the stack will be
1641 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1642 HOST_WIDE_INT adjustment
;
1643 /* The alignment of the stack after the arguments are pushed, if we
1644 just pushed the arguments without adjust the stack here. */
1645 unsigned HOST_WIDE_INT unadjusted_alignment
;
1647 unadjusted_alignment
1648 = ((stack_pointer_delta
+ unadjusted_args_size
)
1649 % preferred_unit_stack_boundary
);
1651 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1652 as possible -- leaving just enough left to cancel out the
1653 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1654 PENDING_STACK_ADJUST is non-negative, and congruent to
1655 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1657 /* Begin by trying to pop all the bytes. */
1658 unadjusted_alignment
1659 = (unadjusted_alignment
1660 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1661 adjustment
= pending_stack_adjust
;
1662 /* Push enough additional bytes that the stack will be aligned
1663 after the arguments are pushed. */
1664 if (preferred_unit_stack_boundary
> 1)
1666 if (unadjusted_alignment
> 0)
1667 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1669 adjustment
+= unadjusted_alignment
;
1672 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1673 bytes after the call. The right number is the entire
1674 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1675 by the arguments in the first place. */
1677 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1682 /* Scan X expression if it does not dereference any argument slots
1683 we already clobbered by tail call arguments (as noted in stored_args_map
1685 Return nonzero if X expression dereferences such argument slots,
1689 check_sibcall_argument_overlap_1 (rtx x
)
1698 code
= GET_CODE (x
);
1701 return mem_overlaps_already_clobbered_arg_p (XEXP (x
, 0),
1702 GET_MODE_SIZE (GET_MODE (x
)));
1704 /* Scan all subexpressions. */
1705 fmt
= GET_RTX_FORMAT (code
);
1706 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
1710 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
1713 else if (*fmt
== 'E')
1715 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
1716 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
1723 /* Scan sequence after INSN if it does not dereference any argument slots
1724 we already clobbered by tail call arguments (as noted in stored_args_map
1725 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1726 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1727 should be 0). Return nonzero if sequence after INSN dereferences such argument
1728 slots, zero otherwise. */
1731 check_sibcall_argument_overlap (rtx insn
, struct arg_data
*arg
, int mark_stored_args_map
)
1735 if (insn
== NULL_RTX
)
1736 insn
= get_insns ();
1738 insn
= NEXT_INSN (insn
);
1740 for (; insn
; insn
= NEXT_INSN (insn
))
1742 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
1745 if (mark_stored_args_map
)
1747 #ifdef ARGS_GROW_DOWNWARD
1748 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
1750 low
= arg
->locate
.slot_offset
.constant
;
1753 for (high
= low
+ arg
->locate
.size
.constant
; low
< high
; low
++)
1754 SET_BIT (stored_args_map
, low
);
1756 return insn
!= NULL_RTX
;
1759 /* Given that a function returns a value of mode MODE at the most
1760 significant end of hard register VALUE, shift VALUE left or right
1761 as specified by LEFT_P. Return true if some action was needed. */
1764 shift_return_value (enum machine_mode mode
, bool left_p
, rtx value
)
1766 HOST_WIDE_INT shift
;
1768 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
1769 shift
= GET_MODE_BITSIZE (GET_MODE (value
)) - GET_MODE_BITSIZE (mode
);
1773 /* Use ashr rather than lshr for right shifts. This is for the benefit
1774 of the MIPS port, which requires SImode values to be sign-extended
1775 when stored in 64-bit registers. */
1776 if (!force_expand_binop (GET_MODE (value
), left_p
? ashl_optab
: ashr_optab
,
1777 value
, GEN_INT (shift
), value
, 1, OPTAB_WIDEN
))
1782 /* Generate all the code for a function call
1783 and return an rtx for its value.
1784 Store the value in TARGET (specified as an rtx) if convenient.
1785 If the value is stored in TARGET then TARGET is returned.
1786 If IGNORE is nonzero, then we ignore the value of the function call. */
1789 expand_call (tree exp
, rtx target
, int ignore
)
1791 /* Nonzero if we are currently expanding a call. */
1792 static int currently_expanding_call
= 0;
1794 /* List of actual parameters. */
1795 tree actparms
= TREE_OPERAND (exp
, 1);
1796 /* RTX for the function to be called. */
1798 /* Sequence of insns to perform a normal "call". */
1799 rtx normal_call_insns
= NULL_RTX
;
1800 /* Sequence of insns to perform a tail "call". */
1801 rtx tail_call_insns
= NULL_RTX
;
1802 /* Data type of the function. */
1804 tree type_arg_types
;
1805 /* Declaration of the function being called,
1806 or 0 if the function is computed (not known by name). */
1808 /* The type of the function being called. */
1810 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
1813 /* Register in which non-BLKmode value will be returned,
1814 or 0 if no value or if value is BLKmode. */
1816 /* Address where we should return a BLKmode value;
1817 0 if value not BLKmode. */
1818 rtx structure_value_addr
= 0;
1819 /* Nonzero if that address is being passed by treating it as
1820 an extra, implicit first parameter. Otherwise,
1821 it is passed by being copied directly into struct_value_rtx. */
1822 int structure_value_addr_parm
= 0;
1823 /* Size of aggregate value wanted, or zero if none wanted
1824 or if we are using the non-reentrant PCC calling convention
1825 or expecting the value in registers. */
1826 HOST_WIDE_INT struct_value_size
= 0;
1827 /* Nonzero if called function returns an aggregate in memory PCC style,
1828 by returning the address of where to find it. */
1829 int pcc_struct_value
= 0;
1830 rtx struct_value
= 0;
1832 /* Number of actual parameters in this call, including struct value addr. */
1834 /* Number of named args. Args after this are anonymous ones
1835 and they must all go on the stack. */
1838 /* Vector of information about each argument.
1839 Arguments are numbered in the order they will be pushed,
1840 not the order they are written. */
1841 struct arg_data
*args
;
1843 /* Total size in bytes of all the stack-parms scanned so far. */
1844 struct args_size args_size
;
1845 struct args_size adjusted_args_size
;
1846 /* Size of arguments before any adjustments (such as rounding). */
1847 int unadjusted_args_size
;
1848 /* Data on reg parms scanned so far. */
1849 CUMULATIVE_ARGS args_so_far
;
1850 /* Nonzero if a reg parm has been scanned. */
1852 /* Nonzero if this is an indirect function call. */
1854 /* Nonzero if we must avoid push-insns in the args for this call.
1855 If stack space is allocated for register parameters, but not by the
1856 caller, then it is preallocated in the fixed part of the stack frame.
1857 So the entire argument block must then be preallocated (i.e., we
1858 ignore PUSH_ROUNDING in that case). */
1860 int must_preallocate
= !PUSH_ARGS
;
1862 /* Size of the stack reserved for parameter registers. */
1863 int reg_parm_stack_space
= 0;
1865 /* Address of space preallocated for stack parms
1866 (on machines that lack push insns), or 0 if space not preallocated. */
1869 /* Mask of ECF_ flags. */
1871 #ifdef REG_PARM_STACK_SPACE
1872 /* Define the boundary of the register parm stack space that needs to be
1874 int low_to_save
, high_to_save
;
1875 rtx save_area
= 0; /* Place that it is saved */
1878 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
1879 char *initial_stack_usage_map
= stack_usage_map
;
1880 char *stack_usage_map_buf
= NULL
;
1882 int old_stack_allocated
;
1884 /* State variables to track stack modifications. */
1885 rtx old_stack_level
= 0;
1886 int old_stack_arg_under_construction
= 0;
1887 int old_pending_adj
= 0;
1888 int old_inhibit_defer_pop
= inhibit_defer_pop
;
1890 /* Some stack pointer alterations we make are performed via
1891 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
1892 which we then also need to save/restore along the way. */
1893 int old_stack_pointer_delta
= 0;
1896 tree p
= TREE_OPERAND (exp
, 0);
1897 tree addr
= TREE_OPERAND (exp
, 0);
1899 /* The alignment of the stack, in bits. */
1900 unsigned HOST_WIDE_INT preferred_stack_boundary
;
1901 /* The alignment of the stack, in bytes. */
1902 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
1903 /* The static chain value to use for this call. */
1904 rtx static_chain_value
;
1905 /* See if this is "nothrow" function call. */
1906 if (TREE_NOTHROW (exp
))
1907 flags
|= ECF_NOTHROW
;
1909 /* See if we can find a DECL-node for the actual function, and get the
1910 function attributes (flags) from the function decl or type node. */
1911 fndecl
= get_callee_fndecl (exp
);
1914 fntype
= TREE_TYPE (fndecl
);
1915 flags
|= flags_from_decl_or_type (fndecl
);
1919 fntype
= TREE_TYPE (TREE_TYPE (p
));
1920 flags
|= flags_from_decl_or_type (fntype
);
1923 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
1925 /* Warn if this value is an aggregate type,
1926 regardless of which calling convention we are using for it. */
1927 if (AGGREGATE_TYPE_P (TREE_TYPE (exp
)))
1928 warning (OPT_Waggregate_return
, "function call has aggregate value");
1930 /* If the result of a pure or const function call is ignored (or void),
1931 and none of its arguments are volatile, we can avoid expanding the
1932 call and just evaluate the arguments for side-effects. */
1933 if ((flags
& (ECF_CONST
| ECF_PURE
))
1934 && (ignore
|| target
== const0_rtx
1935 || TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
))
1937 bool volatilep
= false;
1940 for (arg
= actparms
; arg
; arg
= TREE_CHAIN (arg
))
1941 if (TREE_THIS_VOLATILE (TREE_VALUE (arg
)))
1949 for (arg
= actparms
; arg
; arg
= TREE_CHAIN (arg
))
1950 expand_expr (TREE_VALUE (arg
), const0_rtx
,
1951 VOIDmode
, EXPAND_NORMAL
);
1956 #ifdef REG_PARM_STACK_SPACE
1957 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
1960 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1961 if (reg_parm_stack_space
> 0 && PUSH_ARGS
)
1962 must_preallocate
= 1;
1965 /* Set up a place to return a structure. */
1967 /* Cater to broken compilers. */
1968 if (aggregate_value_p (exp
, fndecl
))
1970 /* This call returns a big structure. */
1971 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
1973 #ifdef PCC_STATIC_STRUCT_RETURN
1975 pcc_struct_value
= 1;
1977 #else /* not PCC_STATIC_STRUCT_RETURN */
1979 struct_value_size
= int_size_in_bytes (TREE_TYPE (exp
));
1981 if (target
&& MEM_P (target
) && CALL_EXPR_RETURN_SLOT_OPT (exp
))
1982 structure_value_addr
= XEXP (target
, 0);
1985 /* For variable-sized objects, we must be called with a target
1986 specified. If we were to allocate space on the stack here,
1987 we would have no way of knowing when to free it. */
1988 rtx d
= assign_temp (TREE_TYPE (exp
), 1, 1, 1);
1990 mark_temp_addr_taken (d
);
1991 structure_value_addr
= XEXP (d
, 0);
1995 #endif /* not PCC_STATIC_STRUCT_RETURN */
1998 /* Figure out the amount to which the stack should be aligned. */
1999 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2002 struct cgraph_rtl_info
*i
= cgraph_rtl_info (fndecl
);
2003 if (i
&& i
->preferred_incoming_stack_boundary
)
2004 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
2007 /* Operand 0 is a pointer-to-function; get the type of the function. */
2008 funtype
= TREE_TYPE (addr
);
2009 gcc_assert (POINTER_TYPE_P (funtype
));
2010 funtype
= TREE_TYPE (funtype
);
2012 /* Munge the tree to split complex arguments into their imaginary
2014 if (targetm
.calls
.split_complex_arg
)
2016 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
2017 actparms
= split_complex_values (actparms
);
2020 type_arg_types
= TYPE_ARG_TYPES (funtype
);
2022 if (flags
& ECF_MAY_BE_ALLOCA
)
2023 current_function_calls_alloca
= 1;
2025 /* If struct_value_rtx is 0, it means pass the address
2026 as if it were an extra parameter. */
2027 if (structure_value_addr
&& struct_value
== 0)
2029 /* If structure_value_addr is a REG other than
2030 virtual_outgoing_args_rtx, we can use always use it. If it
2031 is not a REG, we must always copy it into a register.
2032 If it is virtual_outgoing_args_rtx, we must copy it to another
2033 register in some cases. */
2034 rtx temp
= (!REG_P (structure_value_addr
)
2035 || (ACCUMULATE_OUTGOING_ARGS
2036 && stack_arg_under_construction
2037 && structure_value_addr
== virtual_outgoing_args_rtx
)
2038 ? copy_addr_to_reg (convert_memory_address
2039 (Pmode
, structure_value_addr
))
2040 : structure_value_addr
);
2043 = tree_cons (error_mark_node
,
2044 make_tree (build_pointer_type (TREE_TYPE (funtype
)),
2047 structure_value_addr_parm
= 1;
2050 /* Count the arguments and set NUM_ACTUALS. */
2051 for (p
= actparms
, num_actuals
= 0; p
; p
= TREE_CHAIN (p
))
2054 /* Compute number of named args.
2055 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2057 if (type_arg_types
!= 0)
2059 = (list_length (type_arg_types
)
2060 /* Count the struct value address, if it is passed as a parm. */
2061 + structure_value_addr_parm
);
2063 /* If we know nothing, treat all args as named. */
2064 n_named_args
= num_actuals
;
2066 /* Start updating where the next arg would go.
2068 On some machines (such as the PA) indirect calls have a different
2069 calling convention than normal calls. The fourth argument in
2070 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2072 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
2074 /* Now possibly adjust the number of named args.
2075 Normally, don't include the last named arg if anonymous args follow.
2076 We do include the last named arg if
2077 targetm.calls.strict_argument_naming() returns nonzero.
2078 (If no anonymous args follow, the result of list_length is actually
2079 one too large. This is harmless.)
2081 If targetm.calls.pretend_outgoing_varargs_named() returns
2082 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2083 this machine will be able to place unnamed args that were passed
2084 in registers into the stack. So treat all args as named. This
2085 allows the insns emitting for a specific argument list to be
2086 independent of the function declaration.
2088 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2089 we do not have any reliable way to pass unnamed args in
2090 registers, so we must force them into memory. */
2092 if (type_arg_types
!= 0
2093 && targetm
.calls
.strict_argument_naming (&args_so_far
))
2095 else if (type_arg_types
!= 0
2096 && ! targetm
.calls
.pretend_outgoing_varargs_named (&args_so_far
))
2097 /* Don't include the last named arg. */
2100 /* Treat all args as named. */
2101 n_named_args
= num_actuals
;
2103 /* Make a vector to hold all the information about each arg. */
2104 args
= alloca (num_actuals
* sizeof (struct arg_data
));
2105 memset (args
, 0, num_actuals
* sizeof (struct arg_data
));
2107 /* Build up entries in the ARGS array, compute the size of the
2108 arguments into ARGS_SIZE, etc. */
2109 initialize_argument_information (num_actuals
, args
, &args_size
,
2110 n_named_args
, actparms
, fndecl
,
2111 &args_so_far
, reg_parm_stack_space
,
2112 &old_stack_level
, &old_pending_adj
,
2113 &must_preallocate
, &flags
,
2114 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
2118 /* If this function requires a variable-sized argument list, don't
2119 try to make a cse'able block for this call. We may be able to
2120 do this eventually, but it is too complicated to keep track of
2121 what insns go in the cse'able block and which don't. */
2123 flags
&= ~ECF_LIBCALL_BLOCK
;
2124 must_preallocate
= 1;
2127 /* Now make final decision about preallocating stack space. */
2128 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2132 /* If the structure value address will reference the stack pointer, we
2133 must stabilize it. We don't need to do this if we know that we are
2134 not going to adjust the stack pointer in processing this call. */
2136 if (structure_value_addr
2137 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2138 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2139 structure_value_addr
))
2141 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2142 structure_value_addr
= copy_to_reg (structure_value_addr
);
2144 /* Tail calls can make things harder to debug, and we've traditionally
2145 pushed these optimizations into -O2. Don't try if we're already
2146 expanding a call, as that means we're an argument. Don't try if
2147 there's cleanups, as we know there's code to follow the call. */
2149 if (currently_expanding_call
++ != 0
2150 || !flag_optimize_sibling_calls
2152 || lookup_stmt_eh_region (exp
) >= 0)
2155 /* Rest of purposes for tail call optimizations to fail. */
2157 #ifdef HAVE_sibcall_epilogue
2158 !HAVE_sibcall_epilogue
2163 /* Doing sibling call optimization needs some work, since
2164 structure_value_addr can be allocated on the stack.
2165 It does not seem worth the effort since few optimizable
2166 sibling calls will return a structure. */
2167 || structure_value_addr
!= NULL_RTX
2168 /* Check whether the target is able to optimize the call
2170 || !targetm
.function_ok_for_sibcall (fndecl
, exp
)
2171 /* Functions that do not return exactly once may not be sibcall
2173 || (flags
& (ECF_RETURNS_TWICE
| ECF_NORETURN
))
2174 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
)))
2175 /* If the called function is nested in the current one, it might access
2176 some of the caller's arguments, but could clobber them beforehand if
2177 the argument areas are shared. */
2178 || (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
2179 /* If this function requires more stack slots than the current
2180 function, we cannot change it into a sibling call.
2181 current_function_pretend_args_size is not part of the
2182 stack allocated by our caller. */
2183 || args_size
.constant
> (current_function_args_size
2184 - current_function_pretend_args_size
)
2185 /* If the callee pops its own arguments, then it must pop exactly
2186 the same number of arguments as the current function. */
2187 || (RETURN_POPS_ARGS (fndecl
, funtype
, args_size
.constant
)
2188 != RETURN_POPS_ARGS (current_function_decl
,
2189 TREE_TYPE (current_function_decl
),
2190 current_function_args_size
))
2191 || !lang_hooks
.decls
.ok_for_sibcall (fndecl
))
2194 /* Ensure current function's preferred stack boundary is at least
2195 what we need. We don't have to increase alignment for recursive
2197 if (cfun
->preferred_stack_boundary
< preferred_stack_boundary
2198 && fndecl
!= current_function_decl
)
2199 cfun
->preferred_stack_boundary
= preferred_stack_boundary
;
2200 if (fndecl
== current_function_decl
)
2201 cfun
->recursive_call_emit
= true;
2203 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2205 /* We want to make two insn chains; one for a sibling call, the other
2206 for a normal call. We will select one of the two chains after
2207 initial RTL generation is complete. */
2208 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
2210 int sibcall_failure
= 0;
2211 /* We want to emit any pending stack adjustments before the tail
2212 recursion "call". That way we know any adjustment after the tail
2213 recursion call can be ignored if we indeed use the tail
2215 int save_pending_stack_adjust
= 0;
2216 int save_stack_pointer_delta
= 0;
2218 rtx before_call
, next_arg_reg
;
2222 /* State variables we need to save and restore between
2224 save_pending_stack_adjust
= pending_stack_adjust
;
2225 save_stack_pointer_delta
= stack_pointer_delta
;
2228 flags
&= ~ECF_SIBCALL
;
2230 flags
|= ECF_SIBCALL
;
2232 /* Other state variables that we must reinitialize each time
2233 through the loop (that are not initialized by the loop itself). */
2237 /* Start a new sequence for the normal call case.
2239 From this point on, if the sibling call fails, we want to set
2240 sibcall_failure instead of continuing the loop. */
2243 /* Don't let pending stack adjusts add up to too much.
2244 Also, do all pending adjustments now if there is any chance
2245 this might be a call to alloca or if we are expanding a sibling
2246 call sequence or if we are calling a function that is to return
2247 with stack pointer depressed.
2248 Also do the adjustments before a throwing call, otherwise
2249 exception handling can fail; PR 19225. */
2250 if (pending_stack_adjust
>= 32
2251 || (pending_stack_adjust
> 0
2252 && (flags
& (ECF_MAY_BE_ALLOCA
| ECF_SP_DEPRESSED
)))
2253 || (pending_stack_adjust
> 0
2254 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
2256 do_pending_stack_adjust ();
2258 /* When calling a const function, we must pop the stack args right away,
2259 so that the pop is deleted or moved with the call. */
2260 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
2263 /* Precompute any arguments as needed. */
2265 precompute_arguments (flags
, num_actuals
, args
);
2267 /* Now we are about to start emitting insns that can be deleted
2268 if a libcall is deleted. */
2269 if (pass
&& (flags
& (ECF_LIBCALL_BLOCK
| ECF_MALLOC
)))
2272 if (pass
== 0 && cfun
->stack_protect_guard
)
2273 stack_protect_epilogue ();
2275 adjusted_args_size
= args_size
;
2276 /* Compute the actual size of the argument block required. The variable
2277 and constant sizes must be combined, the size may have to be rounded,
2278 and there may be a minimum required size. When generating a sibcall
2279 pattern, do not round up, since we'll be re-using whatever space our
2281 unadjusted_args_size
2282 = compute_argument_block_size (reg_parm_stack_space
,
2283 &adjusted_args_size
,
2285 : preferred_stack_boundary
));
2287 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2289 /* The argument block when performing a sibling call is the
2290 incoming argument block. */
2293 argblock
= virtual_incoming_args_rtx
;
2295 #ifdef STACK_GROWS_DOWNWARD
2296 = plus_constant (argblock
, current_function_pretend_args_size
);
2298 = plus_constant (argblock
, -current_function_pretend_args_size
);
2300 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2301 sbitmap_zero (stored_args_map
);
2304 /* If we have no actual push instructions, or shouldn't use them,
2305 make space for all args right now. */
2306 else if (adjusted_args_size
.var
!= 0)
2308 if (old_stack_level
== 0)
2310 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
2311 old_stack_pointer_delta
= stack_pointer_delta
;
2312 old_pending_adj
= pending_stack_adjust
;
2313 pending_stack_adjust
= 0;
2314 /* stack_arg_under_construction says whether a stack arg is
2315 being constructed at the old stack level. Pushing the stack
2316 gets a clean outgoing argument block. */
2317 old_stack_arg_under_construction
= stack_arg_under_construction
;
2318 stack_arg_under_construction
= 0;
2320 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2324 /* Note that we must go through the motions of allocating an argument
2325 block even if the size is zero because we may be storing args
2326 in the area reserved for register arguments, which may be part of
2329 int needed
= adjusted_args_size
.constant
;
2331 /* Store the maximum argument space used. It will be pushed by
2332 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2335 if (needed
> current_function_outgoing_args_size
)
2336 current_function_outgoing_args_size
= needed
;
2338 if (must_preallocate
)
2340 if (ACCUMULATE_OUTGOING_ARGS
)
2342 /* Since the stack pointer will never be pushed, it is
2343 possible for the evaluation of a parm to clobber
2344 something we have already written to the stack.
2345 Since most function calls on RISC machines do not use
2346 the stack, this is uncommon, but must work correctly.
2348 Therefore, we save any area of the stack that was already
2349 written and that we are using. Here we set up to do this
2350 by making a new stack usage map from the old one. The
2351 actual save will be done by store_one_arg.
2353 Another approach might be to try to reorder the argument
2354 evaluations to avoid this conflicting stack usage. */
2356 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2357 /* Since we will be writing into the entire argument area,
2358 the map must be allocated for its entire size, not just
2359 the part that is the responsibility of the caller. */
2360 needed
+= reg_parm_stack_space
;
2363 #ifdef ARGS_GROW_DOWNWARD
2364 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2367 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2370 if (stack_usage_map_buf
)
2371 free (stack_usage_map_buf
);
2372 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
2373 stack_usage_map
= stack_usage_map_buf
;
2375 if (initial_highest_arg_in_use
)
2376 memcpy (stack_usage_map
, initial_stack_usage_map
,
2377 initial_highest_arg_in_use
);
2379 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2380 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2381 (highest_outgoing_arg_in_use
2382 - initial_highest_arg_in_use
));
2385 /* The address of the outgoing argument list must not be
2386 copied to a register here, because argblock would be left
2387 pointing to the wrong place after the call to
2388 allocate_dynamic_stack_space below. */
2390 argblock
= virtual_outgoing_args_rtx
;
2394 if (inhibit_defer_pop
== 0)
2396 /* Try to reuse some or all of the pending_stack_adjust
2397 to get this space. */
2399 = (combine_pending_stack_adjustment_and_call
2400 (unadjusted_args_size
,
2401 &adjusted_args_size
,
2402 preferred_unit_stack_boundary
));
2404 /* combine_pending_stack_adjustment_and_call computes
2405 an adjustment before the arguments are allocated.
2406 Account for them and see whether or not the stack
2407 needs to go up or down. */
2408 needed
= unadjusted_args_size
- needed
;
2412 /* We're releasing stack space. */
2413 /* ??? We can avoid any adjustment at all if we're
2414 already aligned. FIXME. */
2415 pending_stack_adjust
= -needed
;
2416 do_pending_stack_adjust ();
2420 /* We need to allocate space. We'll do that in
2421 push_block below. */
2422 pending_stack_adjust
= 0;
2425 /* Special case this because overhead of `push_block' in
2426 this case is non-trivial. */
2428 argblock
= virtual_outgoing_args_rtx
;
2431 argblock
= push_block (GEN_INT (needed
), 0, 0);
2432 #ifdef ARGS_GROW_DOWNWARD
2433 argblock
= plus_constant (argblock
, needed
);
2437 /* We only really need to call `copy_to_reg' in the case
2438 where push insns are going to be used to pass ARGBLOCK
2439 to a function call in ARGS. In that case, the stack
2440 pointer changes value from the allocation point to the
2441 call point, and hence the value of
2442 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2443 as well always do it. */
2444 argblock
= copy_to_reg (argblock
);
2449 if (ACCUMULATE_OUTGOING_ARGS
)
2451 /* The save/restore code in store_one_arg handles all
2452 cases except one: a constructor call (including a C
2453 function returning a BLKmode struct) to initialize
2455 if (stack_arg_under_construction
)
2457 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2458 rtx push_size
= GEN_INT (reg_parm_stack_space
2459 + adjusted_args_size
.constant
);
2461 rtx push_size
= GEN_INT (adjusted_args_size
.constant
);
2463 if (old_stack_level
== 0)
2465 emit_stack_save (SAVE_BLOCK
, &old_stack_level
,
2467 old_stack_pointer_delta
= stack_pointer_delta
;
2468 old_pending_adj
= pending_stack_adjust
;
2469 pending_stack_adjust
= 0;
2470 /* stack_arg_under_construction says whether a stack
2471 arg is being constructed at the old stack level.
2472 Pushing the stack gets a clean outgoing argument
2474 old_stack_arg_under_construction
2475 = stack_arg_under_construction
;
2476 stack_arg_under_construction
= 0;
2477 /* Make a new map for the new argument list. */
2478 if (stack_usage_map_buf
)
2479 free (stack_usage_map_buf
);
2480 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
2481 stack_usage_map
= stack_usage_map_buf
;
2482 memset (stack_usage_map
, 0, highest_outgoing_arg_in_use
);
2483 highest_outgoing_arg_in_use
= 0;
2485 allocate_dynamic_stack_space (push_size
, NULL_RTX
,
2489 /* If argument evaluation might modify the stack pointer,
2490 copy the address of the argument list to a register. */
2491 for (i
= 0; i
< num_actuals
; i
++)
2492 if (args
[i
].pass_on_stack
)
2494 argblock
= copy_addr_to_reg (argblock
);
2499 compute_argument_addresses (args
, argblock
, num_actuals
);
2501 /* If we push args individually in reverse order, perform stack alignment
2502 before the first push (the last arg). */
2503 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2504 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2506 /* When the stack adjustment is pending, we get better code
2507 by combining the adjustments. */
2508 if (pending_stack_adjust
2509 && ! (flags
& ECF_LIBCALL_BLOCK
)
2510 && ! inhibit_defer_pop
)
2512 pending_stack_adjust
2513 = (combine_pending_stack_adjustment_and_call
2514 (unadjusted_args_size
,
2515 &adjusted_args_size
,
2516 preferred_unit_stack_boundary
));
2517 do_pending_stack_adjust ();
2519 else if (argblock
== 0)
2520 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2521 - unadjusted_args_size
));
2523 /* Now that the stack is properly aligned, pops can't safely
2524 be deferred during the evaluation of the arguments. */
2527 funexp
= rtx_for_function_call (fndecl
, addr
);
2529 /* Figure out the register where the value, if any, will come back. */
2531 if (TYPE_MODE (TREE_TYPE (exp
)) != VOIDmode
2532 && ! structure_value_addr
)
2534 if (pcc_struct_value
)
2535 valreg
= hard_function_value (build_pointer_type (TREE_TYPE (exp
)),
2536 fndecl
, NULL
, (pass
== 0));
2538 valreg
= hard_function_value (TREE_TYPE (exp
), fndecl
, fntype
,
2542 /* Precompute all register parameters. It isn't safe to compute anything
2543 once we have started filling any specific hard regs. */
2544 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2546 if (TREE_OPERAND (exp
, 2))
2547 static_chain_value
= expand_normal (TREE_OPERAND (exp
, 2));
2549 static_chain_value
= 0;
2551 #ifdef REG_PARM_STACK_SPACE
2552 /* Save the fixed argument area if it's part of the caller's frame and
2553 is clobbered by argument setup for this call. */
2554 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2555 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2556 &low_to_save
, &high_to_save
);
2559 /* Now store (and compute if necessary) all non-register parms.
2560 These come before register parms, since they can require block-moves,
2561 which could clobber the registers used for register parms.
2562 Parms which have partial registers are not stored here,
2563 but we do preallocate space here if they want that. */
2565 for (i
= 0; i
< num_actuals
; i
++)
2566 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2568 rtx before_arg
= get_last_insn ();
2570 if (store_one_arg (&args
[i
], argblock
, flags
,
2571 adjusted_args_size
.var
!= 0,
2572 reg_parm_stack_space
)
2574 && check_sibcall_argument_overlap (before_arg
,
2576 sibcall_failure
= 1;
2578 if (flags
& ECF_CONST
2580 && args
[i
].value
== args
[i
].stack
)
2581 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
2582 gen_rtx_USE (VOIDmode
,
2587 /* If we have a parm that is passed in registers but not in memory
2588 and whose alignment does not permit a direct copy into registers,
2589 make a group of pseudos that correspond to each register that we
2591 if (STRICT_ALIGNMENT
)
2592 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2594 /* Now store any partially-in-registers parm.
2595 This is the last place a block-move can happen. */
2597 for (i
= 0; i
< num_actuals
; i
++)
2598 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2600 rtx before_arg
= get_last_insn ();
2602 if (store_one_arg (&args
[i
], argblock
, flags
,
2603 adjusted_args_size
.var
!= 0,
2604 reg_parm_stack_space
)
2606 && check_sibcall_argument_overlap (before_arg
,
2608 sibcall_failure
= 1;
2611 /* If we pushed args in forward order, perform stack alignment
2612 after pushing the last arg. */
2613 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
2614 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2615 - unadjusted_args_size
));
2617 /* If register arguments require space on the stack and stack space
2618 was not preallocated, allocate stack space here for arguments
2619 passed in registers. */
2620 #ifdef OUTGOING_REG_PARM_STACK_SPACE
2621 if (!ACCUMULATE_OUTGOING_ARGS
2622 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
2623 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
2626 /* Pass the function the address in which to return a
2628 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
2630 structure_value_addr
2631 = convert_memory_address (Pmode
, structure_value_addr
);
2632 emit_move_insn (struct_value
,
2634 force_operand (structure_value_addr
,
2637 if (REG_P (struct_value
))
2638 use_reg (&call_fusage
, struct_value
);
2641 funexp
= prepare_call_address (funexp
, static_chain_value
,
2642 &call_fusage
, reg_parm_seen
, pass
== 0);
2644 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
2645 pass
== 0, &sibcall_failure
);
2647 /* Save a pointer to the last insn before the call, so that we can
2648 later safely search backwards to find the CALL_INSN. */
2649 before_call
= get_last_insn ();
2651 /* Set up next argument register. For sibling calls on machines
2652 with register windows this should be the incoming register. */
2653 #ifdef FUNCTION_INCOMING_ARG
2655 next_arg_reg
= FUNCTION_INCOMING_ARG (args_so_far
, VOIDmode
,
2659 next_arg_reg
= FUNCTION_ARG (args_so_far
, VOIDmode
,
2662 /* All arguments and registers used for the call must be set up by
2665 /* Stack must be properly aligned now. */
2667 || !(stack_pointer_delta
% preferred_unit_stack_boundary
));
2669 /* Generate the actual call instruction. */
2670 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
2671 adjusted_args_size
.constant
, struct_value_size
,
2672 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
2673 flags
, & args_so_far
);
2675 /* If a non-BLKmode value is returned at the most significant end
2676 of a register, shift the register right by the appropriate amount
2677 and update VALREG accordingly. BLKmode values are handled by the
2678 group load/store machinery below. */
2679 if (!structure_value_addr
2680 && !pcc_struct_value
2681 && TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
2682 && targetm
.calls
.return_in_msb (TREE_TYPE (exp
)))
2684 if (shift_return_value (TYPE_MODE (TREE_TYPE (exp
)), false, valreg
))
2685 sibcall_failure
= 1;
2686 valreg
= gen_rtx_REG (TYPE_MODE (TREE_TYPE (exp
)), REGNO (valreg
));
2689 /* If call is cse'able, make appropriate pair of reg-notes around it.
2690 Test valreg so we don't crash; may safely ignore `const'
2691 if return type is void. Disable for PARALLEL return values, because
2692 we have no way to move such values into a pseudo register. */
2693 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
2697 bool failed
= valreg
== 0 || GET_CODE (valreg
) == PARALLEL
;
2699 insns
= get_insns ();
2701 /* Expansion of block moves possibly introduced a loop that may
2702 not appear inside libcall block. */
2703 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
2715 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2717 /* Mark the return value as a pointer if needed. */
2718 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
2719 mark_reg_pointer (temp
,
2720 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp
))));
2723 if (flag_unsafe_math_optimizations
2725 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
2726 && (DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRT
2727 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRTF
2728 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRTL
))
2729 note
= gen_rtx_fmt_e (SQRT
,
2731 args
[0].initial_value
);
2734 /* Construct an "equal form" for the value which
2735 mentions all the arguments in order as well as
2736 the function name. */
2737 for (i
= 0; i
< num_actuals
; i
++)
2738 note
= gen_rtx_EXPR_LIST (VOIDmode
,
2739 args
[i
].initial_value
, note
);
2740 note
= gen_rtx_EXPR_LIST (VOIDmode
, funexp
, note
);
2742 if (flags
& ECF_PURE
)
2743 note
= gen_rtx_EXPR_LIST (VOIDmode
,
2744 gen_rtx_USE (VOIDmode
,
2745 gen_rtx_MEM (BLKmode
,
2746 gen_rtx_SCRATCH (VOIDmode
))),
2749 emit_libcall_block (insns
, temp
, valreg
, note
);
2754 else if (pass
&& (flags
& ECF_MALLOC
))
2756 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2759 /* The return value from a malloc-like function is a pointer. */
2760 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
2761 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
2763 emit_move_insn (temp
, valreg
);
2765 /* The return value from a malloc-like function can not alias
2767 last
= get_last_insn ();
2769 gen_rtx_EXPR_LIST (REG_NOALIAS
, temp
, REG_NOTES (last
));
2771 /* Write out the sequence. */
2772 insns
= get_insns ();
2778 /* For calls to `setjmp', etc., inform flow.c it should complain
2779 if nonvolatile values are live. For functions that cannot return,
2780 inform flow that control does not fall through. */
2782 if ((flags
& ECF_NORETURN
) || pass
== 0)
2784 /* The barrier must be emitted
2785 immediately after the CALL_INSN. Some ports emit more
2786 than just a CALL_INSN above, so we must search for it here. */
2788 rtx last
= get_last_insn ();
2789 while (!CALL_P (last
))
2791 last
= PREV_INSN (last
);
2792 /* There was no CALL_INSN? */
2793 gcc_assert (last
!= before_call
);
2796 emit_barrier_after (last
);
2798 /* Stack adjustments after a noreturn call are dead code.
2799 However when NO_DEFER_POP is in effect, we must preserve
2800 stack_pointer_delta. */
2801 if (inhibit_defer_pop
== 0)
2803 stack_pointer_delta
= old_stack_allocated
;
2804 pending_stack_adjust
= 0;
2808 /* If value type not void, return an rtx for the value. */
2810 if (TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
2812 target
= const0_rtx
;
2813 else if (structure_value_addr
)
2815 if (target
== 0 || !MEM_P (target
))
2818 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
2819 memory_address (TYPE_MODE (TREE_TYPE (exp
)),
2820 structure_value_addr
));
2821 set_mem_attributes (target
, exp
, 1);
2824 else if (pcc_struct_value
)
2826 /* This is the special C++ case where we need to
2827 know what the true target was. We take care to
2828 never use this value more than once in one expression. */
2829 target
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
2830 copy_to_reg (valreg
));
2831 set_mem_attributes (target
, exp
, 1);
2833 /* Handle calls that return values in multiple non-contiguous locations.
2834 The Irix 6 ABI has examples of this. */
2835 else if (GET_CODE (valreg
) == PARALLEL
)
2839 /* This will only be assigned once, so it can be readonly. */
2840 tree nt
= build_qualified_type (TREE_TYPE (exp
),
2841 (TYPE_QUALS (TREE_TYPE (exp
))
2842 | TYPE_QUAL_CONST
));
2844 target
= assign_temp (nt
, 0, 1, 1);
2847 if (! rtx_equal_p (target
, valreg
))
2848 emit_group_store (target
, valreg
, TREE_TYPE (exp
),
2849 int_size_in_bytes (TREE_TYPE (exp
)));
2851 /* We can not support sibling calls for this case. */
2852 sibcall_failure
= 1;
2855 && GET_MODE (target
) == TYPE_MODE (TREE_TYPE (exp
))
2856 && GET_MODE (target
) == GET_MODE (valreg
))
2858 bool may_overlap
= false;
2860 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
2861 reg to a plain register. */
2863 && HARD_REGISTER_P (valreg
)
2864 && CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (REGNO (valreg
)))
2865 && !(REG_P (target
) && !HARD_REGISTER_P (target
)))
2866 valreg
= copy_to_reg (valreg
);
2868 /* If TARGET is a MEM in the argument area, and we have
2869 saved part of the argument area, then we can't store
2870 directly into TARGET as it may get overwritten when we
2871 restore the argument save area below. Don't work too
2872 hard though and simply force TARGET to a register if it
2873 is a MEM; the optimizer is quite likely to sort it out. */
2874 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
2875 for (i
= 0; i
< num_actuals
; i
++)
2876 if (args
[i
].save_area
)
2883 target
= copy_to_reg (valreg
);
2886 /* TARGET and VALREG cannot be equal at this point
2887 because the latter would not have
2888 REG_FUNCTION_VALUE_P true, while the former would if
2889 it were referring to the same register.
2891 If they refer to the same register, this move will be
2892 a no-op, except when function inlining is being
2894 emit_move_insn (target
, valreg
);
2896 /* If we are setting a MEM, this code must be executed.
2897 Since it is emitted after the call insn, sibcall
2898 optimization cannot be performed in that case. */
2900 sibcall_failure
= 1;
2903 else if (TYPE_MODE (TREE_TYPE (exp
)) == BLKmode
)
2905 target
= copy_blkmode_from_reg (target
, valreg
, TREE_TYPE (exp
));
2907 /* We can not support sibling calls for this case. */
2908 sibcall_failure
= 1;
2911 target
= copy_to_reg (valreg
);
2913 if (targetm
.calls
.promote_function_return(funtype
))
2915 /* If we promoted this return value, make the proper SUBREG.
2916 TARGET might be const0_rtx here, so be careful. */
2918 && TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
2919 && GET_MODE (target
) != TYPE_MODE (TREE_TYPE (exp
)))
2921 tree type
= TREE_TYPE (exp
);
2922 int unsignedp
= TYPE_UNSIGNED (type
);
2924 enum machine_mode pmode
;
2926 pmode
= promote_mode (type
, TYPE_MODE (type
), &unsignedp
, 1);
2927 /* If we don't promote as expected, something is wrong. */
2928 gcc_assert (GET_MODE (target
) == pmode
);
2930 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
2931 && (GET_MODE_SIZE (GET_MODE (target
))
2932 > GET_MODE_SIZE (TYPE_MODE (type
))))
2934 offset
= GET_MODE_SIZE (GET_MODE (target
))
2935 - GET_MODE_SIZE (TYPE_MODE (type
));
2936 if (! BYTES_BIG_ENDIAN
)
2937 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
2938 else if (! WORDS_BIG_ENDIAN
)
2939 offset
%= UNITS_PER_WORD
;
2941 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
2942 SUBREG_PROMOTED_VAR_P (target
) = 1;
2943 SUBREG_PROMOTED_UNSIGNED_SET (target
, unsignedp
);
2947 /* If size of args is variable or this was a constructor call for a stack
2948 argument, restore saved stack-pointer value. */
2950 if (old_stack_level
&& ! (flags
& ECF_SP_DEPRESSED
))
2952 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
2953 stack_pointer_delta
= old_stack_pointer_delta
;
2954 pending_stack_adjust
= old_pending_adj
;
2955 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2956 stack_arg_under_construction
= old_stack_arg_under_construction
;
2957 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
2958 stack_usage_map
= initial_stack_usage_map
;
2959 sibcall_failure
= 1;
2961 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2963 #ifdef REG_PARM_STACK_SPACE
2965 restore_fixed_argument_area (save_area
, argblock
,
2966 high_to_save
, low_to_save
);
2969 /* If we saved any argument areas, restore them. */
2970 for (i
= 0; i
< num_actuals
; i
++)
2971 if (args
[i
].save_area
)
2973 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
2975 = gen_rtx_MEM (save_mode
,
2976 memory_address (save_mode
,
2977 XEXP (args
[i
].stack_slot
, 0)));
2979 if (save_mode
!= BLKmode
)
2980 emit_move_insn (stack_area
, args
[i
].save_area
);
2982 emit_block_move (stack_area
, args
[i
].save_area
,
2983 GEN_INT (args
[i
].locate
.size
.constant
),
2984 BLOCK_OP_CALL_PARM
);
2987 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
2988 stack_usage_map
= initial_stack_usage_map
;
2991 /* If this was alloca, record the new stack level for nonlocal gotos.
2992 Check for the handler slots since we might not have a save area
2993 for non-local gotos. */
2995 if ((flags
& ECF_MAY_BE_ALLOCA
) && cfun
->nonlocal_goto_save_area
!= 0)
2996 update_nonlocal_goto_save_area ();
2998 /* Free up storage we no longer need. */
2999 for (i
= 0; i
< num_actuals
; ++i
)
3000 if (args
[i
].aligned_regs
)
3001 free (args
[i
].aligned_regs
);
3003 insns
= get_insns ();
3008 tail_call_insns
= insns
;
3010 /* Restore the pending stack adjustment now that we have
3011 finished generating the sibling call sequence. */
3013 pending_stack_adjust
= save_pending_stack_adjust
;
3014 stack_pointer_delta
= save_stack_pointer_delta
;
3016 /* Prepare arg structure for next iteration. */
3017 for (i
= 0; i
< num_actuals
; i
++)
3020 args
[i
].aligned_regs
= 0;
3024 sbitmap_free (stored_args_map
);
3028 normal_call_insns
= insns
;
3030 /* Verify that we've deallocated all the stack we used. */
3031 gcc_assert ((flags
& ECF_NORETURN
)
3032 || (old_stack_allocated
3033 == stack_pointer_delta
- pending_stack_adjust
));
3036 /* If something prevents making this a sibling call,
3037 zero out the sequence. */
3038 if (sibcall_failure
)
3039 tail_call_insns
= NULL_RTX
;
3044 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3045 arguments too, as argument area is now clobbered by the call. */
3046 if (tail_call_insns
)
3048 emit_insn (tail_call_insns
);
3049 cfun
->tail_call_emit
= true;
3052 emit_insn (normal_call_insns
);
3054 currently_expanding_call
--;
3056 /* If this function returns with the stack pointer depressed, ensure
3057 this block saves and restores the stack pointer, show it was
3058 changed, and adjust for any outgoing arg space. */
3059 if (flags
& ECF_SP_DEPRESSED
)
3061 clear_pending_stack_adjust ();
3062 emit_insn (gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
));
3063 emit_move_insn (virtual_stack_dynamic_rtx
, stack_pointer_rtx
);
3066 if (stack_usage_map_buf
)
3067 free (stack_usage_map_buf
);
3072 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3073 this function's incoming arguments.
3075 At the start of RTL generation we know the only REG_EQUIV notes
3076 in the rtl chain are those for incoming arguments, so we can look
3077 for REG_EQUIV notes between the start of the function and the
3078 NOTE_INSN_FUNCTION_BEG.
3080 This is (slight) overkill. We could keep track of the highest
3081 argument we clobber and be more selective in removing notes, but it
3082 does not seem to be worth the effort. */
3085 fixup_tail_calls (void)
3089 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
3091 /* There are never REG_EQUIV notes for the incoming arguments
3092 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3094 && NOTE_LINE_NUMBER (insn
) == NOTE_INSN_FUNCTION_BEG
)
3099 rtx note
= find_reg_note (insn
, REG_EQUIV
, 0);
3102 /* Remove the note and keep looking at the notes for
3104 remove_note (insn
, note
);
3112 /* Traverse an argument list in VALUES and expand all complex
3113 arguments into their components. */
3115 split_complex_values (tree values
)
3119 /* Before allocating memory, check for the common case of no complex. */
3120 for (p
= values
; p
; p
= TREE_CHAIN (p
))
3122 tree type
= TREE_TYPE (TREE_VALUE (p
));
3123 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
3124 && targetm
.calls
.split_complex_arg (type
))
3130 values
= copy_list (values
);
3132 for (p
= values
; p
; p
= TREE_CHAIN (p
))
3134 tree complex_value
= TREE_VALUE (p
);
3137 complex_type
= TREE_TYPE (complex_value
);
3141 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
3142 && targetm
.calls
.split_complex_arg (complex_type
))
3145 tree real
, imag
, next
;
3147 subtype
= TREE_TYPE (complex_type
);
3148 complex_value
= save_expr (complex_value
);
3149 real
= build1 (REALPART_EXPR
, subtype
, complex_value
);
3150 imag
= build1 (IMAGPART_EXPR
, subtype
, complex_value
);
3152 TREE_VALUE (p
) = real
;
3153 next
= TREE_CHAIN (p
);
3154 imag
= build_tree_list (NULL_TREE
, imag
);
3155 TREE_CHAIN (p
) = imag
;
3156 TREE_CHAIN (imag
) = next
;
3158 /* Skip the newly created node. */
3166 /* Traverse a list of TYPES and expand all complex types into their
3169 split_complex_types (tree types
)
3173 /* Before allocating memory, check for the common case of no complex. */
3174 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3176 tree type
= TREE_VALUE (p
);
3177 if (TREE_CODE (type
) == COMPLEX_TYPE
3178 && targetm
.calls
.split_complex_arg (type
))
3184 types
= copy_list (types
);
3186 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3188 tree complex_type
= TREE_VALUE (p
);
3190 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
3191 && targetm
.calls
.split_complex_arg (complex_type
))
3195 /* Rewrite complex type with component type. */
3196 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
3197 next
= TREE_CHAIN (p
);
3199 /* Add another component type for the imaginary part. */
3200 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
3201 TREE_CHAIN (p
) = imag
;
3202 TREE_CHAIN (imag
) = next
;
3204 /* Skip the newly created node. */
3212 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3213 The RETVAL parameter specifies whether return value needs to be saved, other
3214 parameters are documented in the emit_library_call function below. */
3217 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
3218 enum libcall_type fn_type
,
3219 enum machine_mode outmode
, int nargs
, va_list p
)
3221 /* Total size in bytes of all the stack-parms scanned so far. */
3222 struct args_size args_size
;
3223 /* Size of arguments before any adjustments (such as rounding). */
3224 struct args_size original_args_size
;
3230 CUMULATIVE_ARGS args_so_far
;
3234 enum machine_mode mode
;
3237 struct locate_and_pad_arg_data locate
;
3241 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3242 rtx call_fusage
= 0;
3245 int pcc_struct_value
= 0;
3246 int struct_value_size
= 0;
3248 int reg_parm_stack_space
= 0;
3251 tree tfom
; /* type_for_mode (outmode, 0) */
3253 #ifdef REG_PARM_STACK_SPACE
3254 /* Define the boundary of the register parm stack space that needs to be
3256 int low_to_save
, high_to_save
;
3257 rtx save_area
= 0; /* Place that it is saved. */
3260 /* Size of the stack reserved for parameter registers. */
3261 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3262 char *initial_stack_usage_map
= stack_usage_map
;
3263 char *stack_usage_map_buf
= NULL
;
3265 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
3267 #ifdef REG_PARM_STACK_SPACE
3268 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3271 /* By default, library functions can not throw. */
3272 flags
= ECF_NOTHROW
;
3284 case LCT_CONST_MAKE_BLOCK
:
3285 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
3287 case LCT_PURE_MAKE_BLOCK
:
3288 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
3291 flags
|= ECF_NORETURN
;
3294 flags
= ECF_NORETURN
;
3296 case LCT_RETURNS_TWICE
:
3297 flags
= ECF_RETURNS_TWICE
;
3302 /* Ensure current function's preferred stack boundary is at least
3304 if (cfun
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3305 cfun
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3307 /* If this kind of value comes back in memory,
3308 decide where in memory it should come back. */
3309 if (outmode
!= VOIDmode
)
3311 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
3312 if (aggregate_value_p (tfom
, 0))
3314 #ifdef PCC_STATIC_STRUCT_RETURN
3316 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
3317 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3318 pcc_struct_value
= 1;
3320 value
= gen_reg_rtx (outmode
);
3321 #else /* not PCC_STATIC_STRUCT_RETURN */
3322 struct_value_size
= GET_MODE_SIZE (outmode
);
3323 if (value
!= 0 && MEM_P (value
))
3326 mem_value
= assign_temp (tfom
, 0, 1, 1);
3328 /* This call returns a big structure. */
3329 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3333 tfom
= void_type_node
;
3335 /* ??? Unfinished: must pass the memory address as an argument. */
3337 /* Copy all the libcall-arguments out of the varargs data
3338 and into a vector ARGVEC.
3340 Compute how to pass each argument. We only support a very small subset
3341 of the full argument passing conventions to limit complexity here since
3342 library functions shouldn't have many args. */
3344 argvec
= alloca ((nargs
+ 1) * sizeof (struct arg
));
3345 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3347 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3348 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3350 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0, nargs
);
3353 args_size
.constant
= 0;
3358 /* Now we are about to start emitting insns that can be deleted
3359 if a libcall is deleted. */
3360 if (flags
& ECF_LIBCALL_BLOCK
)
3365 /* If there's a structure value address to be passed,
3366 either pass it in the special place, or pass it as an extra argument. */
3367 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
3369 rtx addr
= XEXP (mem_value
, 0);
3373 /* Make sure it is a reasonable operand for a move or push insn. */
3374 if (!REG_P (addr
) && !MEM_P (addr
)
3375 && ! (CONSTANT_P (addr
) && LEGITIMATE_CONSTANT_P (addr
)))
3376 addr
= force_operand (addr
, NULL_RTX
);
3378 argvec
[count
].value
= addr
;
3379 argvec
[count
].mode
= Pmode
;
3380 argvec
[count
].partial
= 0;
3382 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, Pmode
, NULL_TREE
, 1);
3383 gcc_assert (targetm
.calls
.arg_partial_bytes (&args_so_far
, Pmode
,
3384 NULL_TREE
, 1) == 0);
3386 locate_and_pad_parm (Pmode
, NULL_TREE
,
3387 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3390 argvec
[count
].reg
!= 0,
3392 0, NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3394 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3395 || reg_parm_stack_space
> 0)
3396 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3398 FUNCTION_ARG_ADVANCE (args_so_far
, Pmode
, (tree
) 0, 1);
3403 for (; count
< nargs
; count
++)
3405 rtx val
= va_arg (p
, rtx
);
3406 enum machine_mode mode
= va_arg (p
, enum machine_mode
);
3408 /* We cannot convert the arg value to the mode the library wants here;
3409 must do it earlier where we know the signedness of the arg. */
3410 gcc_assert (mode
!= BLKmode
3411 && (GET_MODE (val
) == mode
|| GET_MODE (val
) == VOIDmode
));
3413 /* Make sure it is a reasonable operand for a move or push insn. */
3414 if (!REG_P (val
) && !MEM_P (val
)
3415 && ! (CONSTANT_P (val
) && LEGITIMATE_CONSTANT_P (val
)))
3416 val
= force_operand (val
, NULL_RTX
);
3418 if (pass_by_reference (&args_so_far
, mode
, NULL_TREE
, 1))
3422 = !reference_callee_copied (&args_so_far
, mode
, NULL_TREE
, 1);
3424 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3425 functions, so we have to pretend this isn't such a function. */
3426 if (flags
& ECF_LIBCALL_BLOCK
)
3428 rtx insns
= get_insns ();
3432 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3434 /* If this was a CONST function, it is now PURE since
3435 it now reads memory. */
3436 if (flags
& ECF_CONST
)
3438 flags
&= ~ECF_CONST
;
3442 if (GET_MODE (val
) == MEM
&& !must_copy
)
3446 slot
= assign_temp (lang_hooks
.types
.type_for_mode (mode
, 0),
3448 emit_move_insn (slot
, val
);
3451 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3452 gen_rtx_USE (VOIDmode
, slot
),
3455 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3456 gen_rtx_CLOBBER (VOIDmode
,
3461 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3464 argvec
[count
].value
= val
;
3465 argvec
[count
].mode
= mode
;
3467 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, mode
, NULL_TREE
, 1);
3469 argvec
[count
].partial
3470 = targetm
.calls
.arg_partial_bytes (&args_so_far
, mode
, NULL_TREE
, 1);
3472 locate_and_pad_parm (mode
, NULL_TREE
,
3473 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3476 argvec
[count
].reg
!= 0,
3478 argvec
[count
].partial
,
3479 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3481 gcc_assert (!argvec
[count
].locate
.size
.var
);
3483 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3484 || reg_parm_stack_space
> 0)
3485 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3487 FUNCTION_ARG_ADVANCE (args_so_far
, mode
, (tree
) 0, 1);
3490 /* If this machine requires an external definition for library
3491 functions, write one out. */
3492 assemble_external_libcall (fun
);
3494 original_args_size
= args_size
;
3495 args_size
.constant
= (((args_size
.constant
3496 + stack_pointer_delta
3500 - stack_pointer_delta
);
3502 args_size
.constant
= MAX (args_size
.constant
,
3503 reg_parm_stack_space
);
3505 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3506 args_size
.constant
-= reg_parm_stack_space
;
3509 if (args_size
.constant
> current_function_outgoing_args_size
)
3510 current_function_outgoing_args_size
= args_size
.constant
;
3512 if (ACCUMULATE_OUTGOING_ARGS
)
3514 /* Since the stack pointer will never be pushed, it is possible for
3515 the evaluation of a parm to clobber something we have already
3516 written to the stack. Since most function calls on RISC machines
3517 do not use the stack, this is uncommon, but must work correctly.
3519 Therefore, we save any area of the stack that was already written
3520 and that we are using. Here we set up to do this by making a new
3521 stack usage map from the old one.
3523 Another approach might be to try to reorder the argument
3524 evaluations to avoid this conflicting stack usage. */
3526 needed
= args_size
.constant
;
3528 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3529 /* Since we will be writing into the entire argument area, the
3530 map must be allocated for its entire size, not just the part that
3531 is the responsibility of the caller. */
3532 needed
+= reg_parm_stack_space
;
3535 #ifdef ARGS_GROW_DOWNWARD
3536 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3539 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3542 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
3543 stack_usage_map
= stack_usage_map_buf
;
3545 if (initial_highest_arg_in_use
)
3546 memcpy (stack_usage_map
, initial_stack_usage_map
,
3547 initial_highest_arg_in_use
);
3549 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3550 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3551 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3554 /* We must be careful to use virtual regs before they're instantiated,
3555 and real regs afterwards. Loop optimization, for example, can create
3556 new libcalls after we've instantiated the virtual regs, and if we
3557 use virtuals anyway, they won't match the rtl patterns. */
3559 if (virtuals_instantiated
)
3560 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3562 argblock
= virtual_outgoing_args_rtx
;
3567 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3570 /* If we push args individually in reverse order, perform stack alignment
3571 before the first push (the last arg). */
3572 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3573 anti_adjust_stack (GEN_INT (args_size
.constant
3574 - original_args_size
.constant
));
3576 if (PUSH_ARGS_REVERSED
)
3587 #ifdef REG_PARM_STACK_SPACE
3588 if (ACCUMULATE_OUTGOING_ARGS
)
3590 /* The argument list is the property of the called routine and it
3591 may clobber it. If the fixed area has been used for previous
3592 parameters, we must save and restore it. */
3593 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
3594 &low_to_save
, &high_to_save
);
3598 /* Push the args that need to be pushed. */
3600 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3601 are to be pushed. */
3602 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3604 enum machine_mode mode
= argvec
[argnum
].mode
;
3605 rtx val
= argvec
[argnum
].value
;
3606 rtx reg
= argvec
[argnum
].reg
;
3607 int partial
= argvec
[argnum
].partial
;
3608 int lower_bound
= 0, upper_bound
= 0, i
;
3610 if (! (reg
!= 0 && partial
== 0))
3612 if (ACCUMULATE_OUTGOING_ARGS
)
3614 /* If this is being stored into a pre-allocated, fixed-size,
3615 stack area, save any previous data at that location. */
3617 #ifdef ARGS_GROW_DOWNWARD
3618 /* stack_slot is negative, but we want to index stack_usage_map
3619 with positive values. */
3620 upper_bound
= -argvec
[argnum
].locate
.offset
.constant
+ 1;
3621 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
3623 lower_bound
= argvec
[argnum
].locate
.offset
.constant
;
3624 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
3628 /* Don't worry about things in the fixed argument area;
3629 it has already been saved. */
3630 if (i
< reg_parm_stack_space
)
3631 i
= reg_parm_stack_space
;
3632 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
3635 if (i
< upper_bound
)
3637 /* We need to make a save area. */
3639 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
3640 enum machine_mode save_mode
3641 = mode_for_size (size
, MODE_INT
, 1);
3643 = plus_constant (argblock
,
3644 argvec
[argnum
].locate
.offset
.constant
);
3646 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
3648 if (save_mode
== BLKmode
)
3650 argvec
[argnum
].save_area
3651 = assign_stack_temp (BLKmode
,
3652 argvec
[argnum
].locate
.size
.constant
,
3655 emit_block_move (validize_mem (argvec
[argnum
].save_area
),
3657 GEN_INT (argvec
[argnum
].locate
.size
.constant
),
3658 BLOCK_OP_CALL_PARM
);
3662 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3664 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3669 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, PARM_BOUNDARY
,
3670 partial
, reg
, 0, argblock
,
3671 GEN_INT (argvec
[argnum
].locate
.offset
.constant
),
3672 reg_parm_stack_space
,
3673 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
));
3675 /* Now mark the segment we just used. */
3676 if (ACCUMULATE_OUTGOING_ARGS
)
3677 for (i
= lower_bound
; i
< upper_bound
; i
++)
3678 stack_usage_map
[i
] = 1;
3682 if (flags
& ECF_CONST
)
3686 /* Indicate argument access so that alias.c knows that these
3689 use
= plus_constant (argblock
,
3690 argvec
[argnum
].locate
.offset
.constant
);
3692 /* When arguments are pushed, trying to tell alias.c where
3693 exactly this argument is won't work, because the
3694 auto-increment causes confusion. So we merely indicate
3695 that we access something with a known mode somewhere on
3697 use
= gen_rtx_PLUS (Pmode
, virtual_outgoing_args_rtx
,
3698 gen_rtx_SCRATCH (Pmode
));
3699 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
3700 use
= gen_rtx_USE (VOIDmode
, use
);
3701 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
3706 /* If we pushed args in forward order, perform stack alignment
3707 after pushing the last arg. */
3708 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3709 anti_adjust_stack (GEN_INT (args_size
.constant
3710 - original_args_size
.constant
));
3712 if (PUSH_ARGS_REVERSED
)
3717 fun
= prepare_call_address (fun
, NULL
, &call_fusage
, 0, 0);
3719 /* Now load any reg parms into their regs. */
3721 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3722 are to be pushed. */
3723 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3725 enum machine_mode mode
= argvec
[argnum
].mode
;
3726 rtx val
= argvec
[argnum
].value
;
3727 rtx reg
= argvec
[argnum
].reg
;
3728 int partial
= argvec
[argnum
].partial
;
3730 /* Handle calls that pass values in multiple non-contiguous
3731 locations. The PA64 has examples of this for library calls. */
3732 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3733 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
3734 else if (reg
!= 0 && partial
== 0)
3735 emit_move_insn (reg
, val
);
3740 /* Any regs containing parms remain in use through the call. */
3741 for (count
= 0; count
< nargs
; count
++)
3743 rtx reg
= argvec
[count
].reg
;
3744 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3745 use_group_regs (&call_fusage
, reg
);
3747 use_reg (&call_fusage
, reg
);
3750 /* Pass the function the address in which to return a structure value. */
3751 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
3753 emit_move_insn (struct_value
,
3755 force_operand (XEXP (mem_value
, 0),
3757 if (REG_P (struct_value
))
3758 use_reg (&call_fusage
, struct_value
);
3761 /* Don't allow popping to be deferred, since then
3762 cse'ing of library calls could delete a call and leave the pop. */
3764 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
3765 ? hard_libcall_value (outmode
) : NULL_RTX
);
3767 /* Stack must be properly aligned now. */
3768 gcc_assert (!(stack_pointer_delta
3769 & (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1)));
3771 before_call
= get_last_insn ();
3773 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3774 will set inhibit_defer_pop to that value. */
3775 /* The return type is needed to decide how many bytes the function pops.
3776 Signedness plays no role in that, so for simplicity, we pretend it's
3777 always signed. We also assume that the list of arguments passed has
3778 no impact, so we pretend it is unknown. */
3780 emit_call_1 (fun
, NULL
,
3781 get_identifier (XSTR (orgfun
, 0)),
3782 build_function_type (tfom
, NULL_TREE
),
3783 original_args_size
.constant
, args_size
.constant
,
3785 FUNCTION_ARG (args_so_far
, VOIDmode
, void_type_node
, 1),
3787 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, & args_so_far
);
3789 /* For calls to `setjmp', etc., inform flow.c it should complain
3790 if nonvolatile values are live. For functions that cannot return,
3791 inform flow that control does not fall through. */
3793 if (flags
& ECF_NORETURN
)
3795 /* The barrier note must be emitted
3796 immediately after the CALL_INSN. Some ports emit more than
3797 just a CALL_INSN above, so we must search for it here. */
3799 rtx last
= get_last_insn ();
3800 while (!CALL_P (last
))
3802 last
= PREV_INSN (last
);
3803 /* There was no CALL_INSN? */
3804 gcc_assert (last
!= before_call
);
3807 emit_barrier_after (last
);
3810 /* Now restore inhibit_defer_pop to its actual original value. */
3813 /* If call is cse'able, make appropriate pair of reg-notes around it.
3814 Test valreg so we don't crash; may safely ignore `const'
3815 if return type is void. Disable for PARALLEL return values, because
3816 we have no way to move such values into a pseudo register. */
3817 if (flags
& ECF_LIBCALL_BLOCK
)
3823 insns
= get_insns ();
3833 if (GET_CODE (valreg
) == PARALLEL
)
3835 temp
= gen_reg_rtx (outmode
);
3836 emit_group_store (temp
, valreg
, NULL_TREE
,
3837 GET_MODE_SIZE (outmode
));
3841 temp
= gen_reg_rtx (GET_MODE (valreg
));
3843 /* Construct an "equal form" for the value which mentions all the
3844 arguments in order as well as the function name. */
3845 for (i
= 0; i
< nargs
; i
++)
3846 note
= gen_rtx_EXPR_LIST (VOIDmode
, argvec
[i
].value
, note
);
3847 note
= gen_rtx_EXPR_LIST (VOIDmode
, fun
, note
);
3849 insns
= get_insns ();
3852 if (flags
& ECF_PURE
)
3853 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3854 gen_rtx_USE (VOIDmode
,
3855 gen_rtx_MEM (BLKmode
,
3856 gen_rtx_SCRATCH (VOIDmode
))),
3859 emit_libcall_block (insns
, temp
, valreg
, note
);
3866 /* Copy the value to the right place. */
3867 if (outmode
!= VOIDmode
&& retval
)
3873 if (value
!= mem_value
)
3874 emit_move_insn (value
, mem_value
);
3876 else if (GET_CODE (valreg
) == PARALLEL
)
3879 value
= gen_reg_rtx (outmode
);
3880 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
3882 else if (value
!= 0)
3883 emit_move_insn (value
, valreg
);
3888 if (ACCUMULATE_OUTGOING_ARGS
)
3890 #ifdef REG_PARM_STACK_SPACE
3892 restore_fixed_argument_area (save_area
, argblock
,
3893 high_to_save
, low_to_save
);
3896 /* If we saved any argument areas, restore them. */
3897 for (count
= 0; count
< nargs
; count
++)
3898 if (argvec
[count
].save_area
)
3900 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
3901 rtx adr
= plus_constant (argblock
,
3902 argvec
[count
].locate
.offset
.constant
);
3903 rtx stack_area
= gen_rtx_MEM (save_mode
,
3904 memory_address (save_mode
, adr
));
3906 if (save_mode
== BLKmode
)
3907 emit_block_move (stack_area
,
3908 validize_mem (argvec
[count
].save_area
),
3909 GEN_INT (argvec
[count
].locate
.size
.constant
),
3910 BLOCK_OP_CALL_PARM
);
3912 emit_move_insn (stack_area
, argvec
[count
].save_area
);
3915 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3916 stack_usage_map
= initial_stack_usage_map
;
3919 if (stack_usage_map_buf
)
3920 free (stack_usage_map_buf
);
3926 /* Output a library call to function FUN (a SYMBOL_REF rtx)
3927 (emitting the queue unless NO_QUEUE is nonzero),
3928 for a value of mode OUTMODE,
3929 with NARGS different arguments, passed as alternating rtx values
3930 and machine_modes to convert them to.
3932 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
3933 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
3934 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
3935 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
3936 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
3937 or other LCT_ value for other types of library calls. */
3940 emit_library_call (rtx orgfun
, enum libcall_type fn_type
,
3941 enum machine_mode outmode
, int nargs
, ...)
3945 va_start (p
, nargs
);
3946 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
3950 /* Like emit_library_call except that an extra argument, VALUE,
3951 comes second and says where to store the result.
3952 (If VALUE is zero, this function chooses a convenient way
3953 to return the value.
3955 This function returns an rtx for where the value is to be found.
3956 If VALUE is nonzero, VALUE is returned. */
3959 emit_library_call_value (rtx orgfun
, rtx value
,
3960 enum libcall_type fn_type
,
3961 enum machine_mode outmode
, int nargs
, ...)
3966 va_start (p
, nargs
);
3967 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
3974 /* Store a single argument for a function call
3975 into the register or memory area where it must be passed.
3976 *ARG describes the argument value and where to pass it.
3978 ARGBLOCK is the address of the stack-block for all the arguments,
3979 or 0 on a machine where arguments are pushed individually.
3981 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
3982 so must be careful about how the stack is used.
3984 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
3985 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
3986 that we need not worry about saving and restoring the stack.
3988 FNDECL is the declaration of the function we are calling.
3990 Return nonzero if this arg should cause sibcall failure,
3994 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
3995 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
3997 tree pval
= arg
->tree_value
;
4001 int i
, lower_bound
= 0, upper_bound
= 0;
4002 int sibcall_failure
= 0;
4004 if (TREE_CODE (pval
) == ERROR_MARK
)
4007 /* Push a new temporary level for any temporaries we make for
4011 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4013 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4014 save any previous data at that location. */
4015 if (argblock
&& ! variable_size
&& arg
->stack
)
4017 #ifdef ARGS_GROW_DOWNWARD
4018 /* stack_slot is negative, but we want to index stack_usage_map
4019 with positive values. */
4020 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4021 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4025 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
4027 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4028 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4032 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
4036 /* Don't worry about things in the fixed argument area;
4037 it has already been saved. */
4038 if (i
< reg_parm_stack_space
)
4039 i
= reg_parm_stack_space
;
4040 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
4043 if (i
< upper_bound
)
4045 /* We need to make a save area. */
4046 unsigned int size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
4047 enum machine_mode save_mode
= mode_for_size (size
, MODE_INT
, 1);
4048 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
4049 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
4051 if (save_mode
== BLKmode
)
4053 tree ot
= TREE_TYPE (arg
->tree_value
);
4054 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4055 | TYPE_QUAL_CONST
));
4057 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4058 preserve_temp_slots (arg
->save_area
);
4059 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4060 expr_size (arg
->tree_value
),
4061 BLOCK_OP_CALL_PARM
);
4065 arg
->save_area
= gen_reg_rtx (save_mode
);
4066 emit_move_insn (arg
->save_area
, stack_area
);
4072 /* If this isn't going to be placed on both the stack and in registers,
4073 set up the register and number of words. */
4074 if (! arg
->pass_on_stack
)
4076 if (flags
& ECF_SIBCALL
)
4077 reg
= arg
->tail_call_reg
;
4080 partial
= arg
->partial
;
4083 /* Being passed entirely in a register. We shouldn't be called in
4085 gcc_assert (reg
== 0 || partial
!= 0);
4087 /* If this arg needs special alignment, don't load the registers
4089 if (arg
->n_aligned_regs
!= 0)
4092 /* If this is being passed partially in a register, we can't evaluate
4093 it directly into its stack slot. Otherwise, we can. */
4094 if (arg
->value
== 0)
4096 /* stack_arg_under_construction is nonzero if a function argument is
4097 being evaluated directly into the outgoing argument list and
4098 expand_call must take special action to preserve the argument list
4099 if it is called recursively.
4101 For scalar function arguments stack_usage_map is sufficient to
4102 determine which stack slots must be saved and restored. Scalar
4103 arguments in general have pass_on_stack == 0.
4105 If this argument is initialized by a function which takes the
4106 address of the argument (a C++ constructor or a C function
4107 returning a BLKmode structure), then stack_usage_map is
4108 insufficient and expand_call must push the stack around the
4109 function call. Such arguments have pass_on_stack == 1.
4111 Note that it is always safe to set stack_arg_under_construction,
4112 but this generates suboptimal code if set when not needed. */
4114 if (arg
->pass_on_stack
)
4115 stack_arg_under_construction
++;
4117 arg
->value
= expand_expr (pval
,
4119 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4120 ? NULL_RTX
: arg
->stack
,
4121 VOIDmode
, EXPAND_STACK_PARM
);
4123 /* If we are promoting object (or for any other reason) the mode
4124 doesn't agree, convert the mode. */
4126 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4127 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4128 arg
->value
, arg
->unsignedp
);
4130 if (arg
->pass_on_stack
)
4131 stack_arg_under_construction
--;
4134 /* Check for overlap with already clobbered argument area. */
4135 if ((flags
& ECF_SIBCALL
)
4136 && MEM_P (arg
->value
)
4137 && mem_overlaps_already_clobbered_arg_p (XEXP (arg
->value
, 0),
4138 arg
->locate
.size
.constant
))
4139 sibcall_failure
= 1;
4141 /* Don't allow anything left on stack from computation
4142 of argument to alloca. */
4143 if (flags
& ECF_MAY_BE_ALLOCA
)
4144 do_pending_stack_adjust ();
4146 if (arg
->value
== arg
->stack
)
4147 /* If the value is already in the stack slot, we are done. */
4149 else if (arg
->mode
!= BLKmode
)
4153 /* Argument is a scalar, not entirely passed in registers.
4154 (If part is passed in registers, arg->partial says how much
4155 and emit_push_insn will take care of putting it there.)
4157 Push it, and if its size is less than the
4158 amount of space allocated to it,
4159 also bump stack pointer by the additional space.
4160 Note that in C the default argument promotions
4161 will prevent such mismatches. */
4163 size
= GET_MODE_SIZE (arg
->mode
);
4164 /* Compute how much space the push instruction will push.
4165 On many machines, pushing a byte will advance the stack
4166 pointer by a halfword. */
4167 #ifdef PUSH_ROUNDING
4168 size
= PUSH_ROUNDING (size
);
4172 /* Compute how much space the argument should get:
4173 round up to a multiple of the alignment for arguments. */
4174 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4175 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4176 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4177 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4179 /* This isn't already where we want it on the stack, so put it there.
4180 This can either be done with push or copy insns. */
4181 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
,
4182 PARM_BOUNDARY
, partial
, reg
, used
- size
, argblock
,
4183 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4184 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4186 /* Unless this is a partially-in-register argument, the argument is now
4189 arg
->value
= arg
->stack
;
4193 /* BLKmode, at least partly to be pushed. */
4195 unsigned int parm_align
;
4199 /* Pushing a nonscalar.
4200 If part is passed in registers, PARTIAL says how much
4201 and emit_push_insn will take care of putting it there. */
4203 /* Round its size up to a multiple
4204 of the allocation unit for arguments. */
4206 if (arg
->locate
.size
.var
!= 0)
4209 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
4213 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4214 for BLKmode is careful to avoid it. */
4215 excess
= (arg
->locate
.size
.constant
4216 - int_size_in_bytes (TREE_TYPE (pval
))
4218 size_rtx
= expand_expr (size_in_bytes (TREE_TYPE (pval
)),
4219 NULL_RTX
, TYPE_MODE (sizetype
), 0);
4222 parm_align
= arg
->locate
.boundary
;
4224 /* When an argument is padded down, the block is aligned to
4225 PARM_BOUNDARY, but the actual argument isn't. */
4226 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4228 if (arg
->locate
.size
.var
)
4229 parm_align
= BITS_PER_UNIT
;
4232 unsigned int excess_align
= (excess
& -excess
) * BITS_PER_UNIT
;
4233 parm_align
= MIN (parm_align
, excess_align
);
4237 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
4239 /* emit_push_insn might not work properly if arg->value and
4240 argblock + arg->locate.offset areas overlap. */
4244 if (XEXP (x
, 0) == current_function_internal_arg_pointer
4245 || (GET_CODE (XEXP (x
, 0)) == PLUS
4246 && XEXP (XEXP (x
, 0), 0) ==
4247 current_function_internal_arg_pointer
4248 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
))
4250 if (XEXP (x
, 0) != current_function_internal_arg_pointer
)
4251 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4253 /* expand_call should ensure this. */
4254 gcc_assert (!arg
->locate
.offset
.var
4255 && GET_CODE (size_rtx
) == CONST_INT
);
4257 if (arg
->locate
.offset
.constant
> i
)
4259 if (arg
->locate
.offset
.constant
< i
+ INTVAL (size_rtx
))
4260 sibcall_failure
= 1;
4262 else if (arg
->locate
.offset
.constant
< i
)
4264 if (i
< arg
->locate
.offset
.constant
+ INTVAL (size_rtx
))
4265 sibcall_failure
= 1;
4270 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4271 parm_align
, partial
, reg
, excess
, argblock
,
4272 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4273 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4275 /* Unless this is a partially-in-register argument, the argument is now
4278 ??? Unlike the case above, in which we want the actual
4279 address of the data, so that we can load it directly into a
4280 register, here we want the address of the stack slot, so that
4281 it's properly aligned for word-by-word copying or something
4282 like that. It's not clear that this is always correct. */
4284 arg
->value
= arg
->stack_slot
;
4287 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
4289 tree type
= TREE_TYPE (arg
->tree_value
);
4291 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
4292 int_size_in_bytes (type
));
4295 /* Mark all slots this store used. */
4296 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
4297 && argblock
&& ! variable_size
&& arg
->stack
)
4298 for (i
= lower_bound
; i
< upper_bound
; i
++)
4299 stack_usage_map
[i
] = 1;
4301 /* Once we have pushed something, pops can't safely
4302 be deferred during the rest of the arguments. */
4305 /* Free any temporary slots made in processing this argument. Show
4306 that we might have taken the address of something and pushed that
4308 preserve_temp_slots (NULL_RTX
);
4312 return sibcall_failure
;
4315 /* Nonzero if we do not know how to pass TYPE solely in registers. */
4318 must_pass_in_stack_var_size (enum machine_mode mode ATTRIBUTE_UNUSED
,
4324 /* If the type has variable size... */
4325 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4328 /* If the type is marked as addressable (it is required
4329 to be constructed into the stack)... */
4330 if (TREE_ADDRESSABLE (type
))
4336 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
4337 takes trailing padding of a structure into account. */
4338 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
4341 must_pass_in_stack_var_size_or_pad (enum machine_mode mode
, tree type
)
4346 /* If the type has variable size... */
4347 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4350 /* If the type is marked as addressable (it is required
4351 to be constructed into the stack)... */
4352 if (TREE_ADDRESSABLE (type
))
4355 /* If the padding and mode of the type is such that a copy into
4356 a register would put it into the wrong part of the register. */
4358 && int_size_in_bytes (type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
4359 && (FUNCTION_ARG_PADDING (mode
, type
)
4360 == (BYTES_BIG_ENDIAN
? upward
: downward
)))