1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
4 2011 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
24 #include "coretypes.h"
35 #include "diagnostic-core.h"
40 #include "langhooks.h"
45 #include "tree-flow.h"
47 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
48 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
50 /* Data structure and subroutines used within expand_call. */
54 /* Tree node for this argument. */
56 /* Mode for value; TYPE_MODE unless promoted. */
57 enum machine_mode mode
;
58 /* Current RTL value for argument, or 0 if it isn't precomputed. */
60 /* Initially-compute RTL value for argument; only for const functions. */
62 /* Register to pass this argument in, 0 if passed on stack, or an
63 PARALLEL if the arg is to be copied into multiple non-contiguous
66 /* Register to pass this argument in when generating tail call sequence.
67 This is not the same register as for normal calls on machines with
70 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
71 form for emit_group_move. */
73 /* If REG was promoted from the actual mode of the argument expression,
74 indicates whether the promotion is sign- or zero-extended. */
76 /* Number of bytes to put in registers. 0 means put the whole arg
77 in registers. Also 0 if not passed in registers. */
79 /* Nonzero if argument must be passed on stack.
80 Note that some arguments may be passed on the stack
81 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
82 pass_on_stack identifies arguments that *cannot* go in registers. */
84 /* Some fields packaged up for locate_and_pad_parm. */
85 struct locate_and_pad_arg_data locate
;
86 /* Location on the stack at which parameter should be stored. The store
87 has already been done if STACK == VALUE. */
89 /* Location on the stack of the start of this argument slot. This can
90 differ from STACK if this arg pads downward. This location is known
91 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
93 /* Place that this stack area has been saved, if needed. */
95 /* If an argument's alignment does not permit direct copying into registers,
96 copy in smaller-sized pieces into pseudos. These are stored in a
97 block pointed to by this field. The next field says how many
98 word-sized pseudos we made. */
103 /* A vector of one char per byte of stack space. A byte if nonzero if
104 the corresponding stack location has been used.
105 This vector is used to prevent a function call within an argument from
106 clobbering any stack already set up. */
107 static char *stack_usage_map
;
109 /* Size of STACK_USAGE_MAP. */
110 static int highest_outgoing_arg_in_use
;
112 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
113 stack location's tail call argument has been already stored into the stack.
114 This bitmap is used to prevent sibling call optimization if function tries
115 to use parent's incoming argument slots when they have been already
116 overwritten with tail call arguments. */
117 static sbitmap stored_args_map
;
119 /* stack_arg_under_construction is nonzero when an argument may be
120 initialized with a constructor call (including a C function that
121 returns a BLKmode struct) and expand_call must take special action
122 to make sure the object being constructed does not overlap the
123 argument list for the constructor call. */
124 static int stack_arg_under_construction
;
126 static void emit_call_1 (rtx
, tree
, tree
, tree
, HOST_WIDE_INT
, HOST_WIDE_INT
,
127 HOST_WIDE_INT
, rtx
, rtx
, int, rtx
, int,
129 static void precompute_register_parameters (int, struct arg_data
*, int *);
130 static int store_one_arg (struct arg_data
*, rtx
, int, int, int);
131 static void store_unaligned_arguments_into_pseudos (struct arg_data
*, int);
132 static int finalize_must_preallocate (int, int, struct arg_data
*,
134 static void precompute_arguments (int, struct arg_data
*);
135 static int compute_argument_block_size (int, struct args_size
*, tree
, tree
, int);
136 static void initialize_argument_information (int, struct arg_data
*,
137 struct args_size
*, int,
139 tree
, tree
, CUMULATIVE_ARGS
*, int,
140 rtx
*, int *, int *, int *,
142 static void compute_argument_addresses (struct arg_data
*, rtx
, int);
143 static rtx
rtx_for_function_call (tree
, tree
);
144 static void load_register_parameters (struct arg_data
*, int, rtx
*, int,
146 static rtx
emit_library_call_value_1 (int, rtx
, rtx
, enum libcall_type
,
147 enum machine_mode
, int, va_list);
148 static int special_function_p (const_tree
, int);
149 static int check_sibcall_argument_overlap_1 (rtx
);
150 static int check_sibcall_argument_overlap (rtx
, struct arg_data
*, int);
152 static int combine_pending_stack_adjustment_and_call (int, struct args_size
*,
154 static tree
split_complex_types (tree
);
156 #ifdef REG_PARM_STACK_SPACE
157 static rtx
save_fixed_argument_area (int, rtx
, int *, int *);
158 static void restore_fixed_argument_area (rtx
, rtx
, int, int);
161 /* Force FUNEXP into a form suitable for the address of a CALL,
162 and return that as an rtx. Also load the static chain register
163 if FNDECL is a nested function.
165 CALL_FUSAGE points to a variable holding the prospective
166 CALL_INSN_FUNCTION_USAGE information. */
169 prepare_call_address (tree fndecl
, rtx funexp
, rtx static_chain_value
,
170 rtx
*call_fusage
, int reg_parm_seen
, int sibcallp
)
172 /* Make a valid memory address and copy constants through pseudo-regs,
173 but not for a constant address if -fno-function-cse. */
174 if (GET_CODE (funexp
) != SYMBOL_REF
)
175 /* If we are using registers for parameters, force the
176 function address into a register now. */
177 funexp
= ((reg_parm_seen
178 && targetm
.small_register_classes_for_mode_p (FUNCTION_MODE
))
179 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
180 : memory_address (FUNCTION_MODE
, funexp
));
183 #ifndef NO_FUNCTION_CSE
184 if (optimize
&& ! flag_no_function_cse
)
185 funexp
= force_reg (Pmode
, funexp
);
189 if (static_chain_value
!= 0)
194 chain
= targetm
.calls
.static_chain (fndecl
, false);
195 static_chain_value
= convert_memory_address (Pmode
, static_chain_value
);
197 emit_move_insn (chain
, static_chain_value
);
199 use_reg (call_fusage
, chain
);
205 /* Generate instructions to call function FUNEXP,
206 and optionally pop the results.
207 The CALL_INSN is the first insn generated.
209 FNDECL is the declaration node of the function. This is given to the
210 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
213 FUNTYPE is the data type of the function. This is given to the hook
214 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
215 own args. We used to allow an identifier for library functions, but
216 that doesn't work when the return type is an aggregate type and the
217 calling convention says that the pointer to this aggregate is to be
218 popped by the callee.
220 STACK_SIZE is the number of bytes of arguments on the stack,
221 ROUNDED_STACK_SIZE is that number rounded up to
222 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
223 both to put into the call insn and to generate explicit popping
226 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
227 It is zero if this call doesn't want a structure value.
229 NEXT_ARG_REG is the rtx that results from executing
230 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
231 just after all the args have had their registers assigned.
232 This could be whatever you like, but normally it is the first
233 arg-register beyond those used for args in this call,
234 or 0 if all the arg-registers are used in this call.
235 It is passed on to `gen_call' so you can put this info in the call insn.
237 VALREG is a hard register in which a value is returned,
238 or 0 if the call does not return a value.
240 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
241 the args to this call were processed.
242 We restore `inhibit_defer_pop' to that value.
244 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
245 denote registers used by the called function. */
248 emit_call_1 (rtx funexp
, tree fntree ATTRIBUTE_UNUSED
, tree fndecl ATTRIBUTE_UNUSED
,
249 tree funtype ATTRIBUTE_UNUSED
,
250 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED
,
251 HOST_WIDE_INT rounded_stack_size
,
252 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED
,
253 rtx next_arg_reg ATTRIBUTE_UNUSED
, rtx valreg
,
254 int old_inhibit_defer_pop
, rtx call_fusage
, int ecf_flags
,
255 CUMULATIVE_ARGS
*args_so_far ATTRIBUTE_UNUSED
)
257 rtx rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
258 rtx call_insn
, call
, funmem
;
259 int already_popped
= 0;
260 HOST_WIDE_INT n_popped
261 = targetm
.calls
.return_pops_args (fndecl
, funtype
, stack_size
);
263 #ifdef CALL_POPS_ARGS
264 n_popped
+= CALL_POPS_ARGS (* args_so_far
);
267 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
268 and we don't want to load it into a register as an optimization,
269 because prepare_call_address already did it if it should be done. */
270 if (GET_CODE (funexp
) != SYMBOL_REF
)
271 funexp
= memory_address (FUNCTION_MODE
, funexp
);
273 funmem
= gen_rtx_MEM (FUNCTION_MODE
, funexp
);
274 if (fndecl
&& TREE_CODE (fndecl
) == FUNCTION_DECL
)
275 set_mem_expr (funmem
, fndecl
);
277 set_mem_expr (funmem
, build_simple_mem_ref (CALL_EXPR_FN (fntree
)));
279 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
280 if ((ecf_flags
& ECF_SIBCALL
)
281 && HAVE_sibcall_pop
&& HAVE_sibcall_value_pop
282 && (n_popped
> 0 || stack_size
== 0))
284 rtx n_pop
= GEN_INT (n_popped
);
287 /* If this subroutine pops its own args, record that in the call insn
288 if possible, for the sake of frame pointer elimination. */
291 pat
= GEN_SIBCALL_VALUE_POP (valreg
, funmem
, rounded_stack_size_rtx
,
292 next_arg_reg
, n_pop
);
294 pat
= GEN_SIBCALL_POP (funmem
, rounded_stack_size_rtx
, next_arg_reg
,
297 emit_call_insn (pat
);
303 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
304 /* If the target has "call" or "call_value" insns, then prefer them
305 if no arguments are actually popped. If the target does not have
306 "call" or "call_value" insns, then we must use the popping versions
307 even if the call has no arguments to pop. */
308 #if defined (HAVE_call) && defined (HAVE_call_value)
309 if (HAVE_call
&& HAVE_call_value
&& HAVE_call_pop
&& HAVE_call_value_pop
312 if (HAVE_call_pop
&& HAVE_call_value_pop
)
315 rtx n_pop
= GEN_INT (n_popped
);
318 /* If this subroutine pops its own args, record that in the call insn
319 if possible, for the sake of frame pointer elimination. */
322 pat
= GEN_CALL_VALUE_POP (valreg
, funmem
, rounded_stack_size_rtx
,
323 next_arg_reg
, n_pop
);
325 pat
= GEN_CALL_POP (funmem
, rounded_stack_size_rtx
, next_arg_reg
,
328 emit_call_insn (pat
);
334 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
335 if ((ecf_flags
& ECF_SIBCALL
)
336 && HAVE_sibcall
&& HAVE_sibcall_value
)
339 emit_call_insn (GEN_SIBCALL_VALUE (valreg
, funmem
,
340 rounded_stack_size_rtx
,
341 next_arg_reg
, NULL_RTX
));
343 emit_call_insn (GEN_SIBCALL (funmem
, rounded_stack_size_rtx
,
345 GEN_INT (struct_value_size
)));
350 #if defined (HAVE_call) && defined (HAVE_call_value)
351 if (HAVE_call
&& HAVE_call_value
)
354 emit_call_insn (GEN_CALL_VALUE (valreg
, funmem
, rounded_stack_size_rtx
,
355 next_arg_reg
, NULL_RTX
));
357 emit_call_insn (GEN_CALL (funmem
, rounded_stack_size_rtx
, next_arg_reg
,
358 GEN_INT (struct_value_size
)));
364 /* Find the call we just emitted. */
365 call_insn
= last_call_insn ();
367 /* Some target create a fresh MEM instead of reusing the one provided
368 above. Set its MEM_EXPR. */
369 call
= PATTERN (call_insn
);
370 if (GET_CODE (call
) == PARALLEL
)
371 call
= XVECEXP (call
, 0, 0);
372 if (GET_CODE (call
) == SET
)
373 call
= SET_SRC (call
);
374 if (GET_CODE (call
) == CALL
375 && MEM_P (XEXP (call
, 0))
376 && MEM_EXPR (XEXP (call
, 0)) == NULL_TREE
377 && MEM_EXPR (funmem
) != NULL_TREE
)
378 set_mem_expr (XEXP (call
, 0), MEM_EXPR (funmem
));
380 /* Put the register usage information there. */
381 add_function_usage_to (call_insn
, call_fusage
);
383 /* If this is a const call, then set the insn's unchanging bit. */
384 if (ecf_flags
& ECF_CONST
)
385 RTL_CONST_CALL_P (call_insn
) = 1;
387 /* If this is a pure call, then set the insn's unchanging bit. */
388 if (ecf_flags
& ECF_PURE
)
389 RTL_PURE_CALL_P (call_insn
) = 1;
391 /* If this is a const call, then set the insn's unchanging bit. */
392 if (ecf_flags
& ECF_LOOPING_CONST_OR_PURE
)
393 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn
) = 1;
395 /* Create a nothrow REG_EH_REGION note, if needed. */
396 make_reg_eh_region_note (call_insn
, ecf_flags
, 0);
398 if (ecf_flags
& ECF_NORETURN
)
399 add_reg_note (call_insn
, REG_NORETURN
, const0_rtx
);
401 if (ecf_flags
& ECF_RETURNS_TWICE
)
403 add_reg_note (call_insn
, REG_SETJMP
, const0_rtx
);
404 cfun
->calls_setjmp
= 1;
407 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
409 /* Restore this now, so that we do defer pops for this call's args
410 if the context of the call as a whole permits. */
411 inhibit_defer_pop
= old_inhibit_defer_pop
;
416 CALL_INSN_FUNCTION_USAGE (call_insn
)
417 = gen_rtx_EXPR_LIST (VOIDmode
,
418 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
419 CALL_INSN_FUNCTION_USAGE (call_insn
));
420 rounded_stack_size
-= n_popped
;
421 rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
422 stack_pointer_delta
-= n_popped
;
424 /* If popup is needed, stack realign must use DRAP */
425 if (SUPPORTS_STACK_ALIGNMENT
)
426 crtl
->need_drap
= true;
429 if (!ACCUMULATE_OUTGOING_ARGS
)
431 /* If returning from the subroutine does not automatically pop the args,
432 we need an instruction to pop them sooner or later.
433 Perhaps do it now; perhaps just record how much space to pop later.
435 If returning from the subroutine does pop the args, indicate that the
436 stack pointer will be changed. */
438 if (rounded_stack_size
!= 0)
440 if (ecf_flags
& ECF_NORETURN
)
441 /* Just pretend we did the pop. */
442 stack_pointer_delta
-= rounded_stack_size
;
443 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
444 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
445 pending_stack_adjust
+= rounded_stack_size
;
447 adjust_stack (rounded_stack_size_rtx
);
450 /* When we accumulate outgoing args, we must avoid any stack manipulations.
451 Restore the stack pointer to its original value now. Usually
452 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
453 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
454 popping variants of functions exist as well.
456 ??? We may optimize similar to defer_pop above, but it is
457 probably not worthwhile.
459 ??? It will be worthwhile to enable combine_stack_adjustments even for
462 anti_adjust_stack (GEN_INT (n_popped
));
465 /* Determine if the function identified by NAME and FNDECL is one with
466 special properties we wish to know about.
468 For example, if the function might return more than one time (setjmp), then
469 set RETURNS_TWICE to a nonzero value.
471 Similarly set NORETURN if the function is in the longjmp family.
473 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
474 space from the stack such as alloca. */
477 special_function_p (const_tree fndecl
, int flags
)
479 if (fndecl
&& DECL_NAME (fndecl
)
480 && IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) <= 17
481 /* Exclude functions not at the file scope, or not `extern',
482 since they are not the magic functions we would otherwise
484 FIXME: this should be handled with attributes, not with this
485 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
486 because you can declare fork() inside a function if you
488 && (DECL_CONTEXT (fndecl
) == NULL_TREE
489 || TREE_CODE (DECL_CONTEXT (fndecl
)) == TRANSLATION_UNIT_DECL
)
490 && TREE_PUBLIC (fndecl
))
492 const char *name
= IDENTIFIER_POINTER (DECL_NAME (fndecl
));
493 const char *tname
= name
;
495 /* We assume that alloca will always be called by name. It
496 makes no sense to pass it as a pointer-to-function to
497 anything that does not understand its behavior. */
498 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 6
500 && ! strcmp (name
, "alloca"))
501 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 16
503 && ! strcmp (name
, "__builtin_alloca"))))
504 flags
|= ECF_MAY_BE_ALLOCA
;
506 /* Disregard prefix _, __, __x or __builtin_. */
511 && !strncmp (name
+ 3, "uiltin_", 7))
513 else if (name
[1] == '_' && name
[2] == 'x')
515 else if (name
[1] == '_')
524 && (! strcmp (tname
, "setjmp")
525 || ! strcmp (tname
, "setjmp_syscall")))
527 && ! strcmp (tname
, "sigsetjmp"))
529 && ! strcmp (tname
, "savectx")))
530 flags
|= ECF_RETURNS_TWICE
;
533 && ! strcmp (tname
, "siglongjmp"))
534 flags
|= ECF_NORETURN
;
536 else if ((tname
[0] == 'q' && tname
[1] == 's'
537 && ! strcmp (tname
, "qsetjmp"))
538 || (tname
[0] == 'v' && tname
[1] == 'f'
539 && ! strcmp (tname
, "vfork"))
540 || (tname
[0] == 'g' && tname
[1] == 'e'
541 && !strcmp (tname
, "getcontext")))
542 flags
|= ECF_RETURNS_TWICE
;
544 else if (tname
[0] == 'l' && tname
[1] == 'o'
545 && ! strcmp (tname
, "longjmp"))
546 flags
|= ECF_NORETURN
;
552 /* Return nonzero when FNDECL represents a call to setjmp. */
555 setjmp_call_p (const_tree fndecl
)
557 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
561 /* Return true if STMT is an alloca call. */
564 gimple_alloca_call_p (const_gimple stmt
)
568 if (!is_gimple_call (stmt
))
571 fndecl
= gimple_call_fndecl (stmt
);
572 if (fndecl
&& (special_function_p (fndecl
, 0) & ECF_MAY_BE_ALLOCA
))
578 /* Return true when exp contains alloca call. */
581 alloca_call_p (const_tree exp
)
583 if (TREE_CODE (exp
) == CALL_EXPR
584 && TREE_CODE (CALL_EXPR_FN (exp
)) == ADDR_EXPR
585 && (TREE_CODE (TREE_OPERAND (CALL_EXPR_FN (exp
), 0)) == FUNCTION_DECL
)
586 && (special_function_p (TREE_OPERAND (CALL_EXPR_FN (exp
), 0), 0)
587 & ECF_MAY_BE_ALLOCA
))
592 /* Detect flags (function attributes) from the function decl or type node. */
595 flags_from_decl_or_type (const_tree exp
)
601 /* The function exp may have the `malloc' attribute. */
602 if (DECL_IS_MALLOC (exp
))
605 /* The function exp may have the `returns_twice' attribute. */
606 if (DECL_IS_RETURNS_TWICE (exp
))
607 flags
|= ECF_RETURNS_TWICE
;
609 /* Process the pure and const attributes. */
610 if (TREE_READONLY (exp
))
612 if (DECL_PURE_P (exp
))
614 if (DECL_LOOPING_CONST_OR_PURE_P (exp
))
615 flags
|= ECF_LOOPING_CONST_OR_PURE
;
617 if (DECL_IS_NOVOPS (exp
))
619 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp
)))
622 if (TREE_NOTHROW (exp
))
623 flags
|= ECF_NOTHROW
;
625 flags
= special_function_p (exp
, flags
);
627 else if (TYPE_P (exp
) && TYPE_READONLY (exp
))
630 if (TREE_THIS_VOLATILE (exp
))
632 flags
|= ECF_NORETURN
;
633 if (flags
& (ECF_CONST
|ECF_PURE
))
634 flags
|= ECF_LOOPING_CONST_OR_PURE
;
640 /* Detect flags from a CALL_EXPR. */
643 call_expr_flags (const_tree t
)
646 tree decl
= get_callee_fndecl (t
);
649 flags
= flags_from_decl_or_type (decl
);
652 t
= TREE_TYPE (CALL_EXPR_FN (t
));
653 if (t
&& TREE_CODE (t
) == POINTER_TYPE
)
654 flags
= flags_from_decl_or_type (TREE_TYPE (t
));
662 /* Precompute all register parameters as described by ARGS, storing values
663 into fields within the ARGS array.
665 NUM_ACTUALS indicates the total number elements in the ARGS array.
667 Set REG_PARM_SEEN if we encounter a register parameter. */
670 precompute_register_parameters (int num_actuals
, struct arg_data
*args
,
677 for (i
= 0; i
< num_actuals
; i
++)
678 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
682 if (args
[i
].value
== 0)
685 args
[i
].value
= expand_normal (args
[i
].tree_value
);
686 preserve_temp_slots (args
[i
].value
);
690 /* If the value is a non-legitimate constant, force it into a
691 pseudo now. TLS symbols sometimes need a call to resolve. */
692 if (CONSTANT_P (args
[i
].value
)
693 && !targetm
.legitimate_constant_p (args
[i
].mode
, args
[i
].value
))
694 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
696 /* If we are to promote the function arg to a wider mode,
699 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
701 = convert_modes (args
[i
].mode
,
702 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
703 args
[i
].value
, args
[i
].unsignedp
);
705 /* If we're going to have to load the value by parts, pull the
706 parts into pseudos. The part extraction process can involve
707 non-trivial computation. */
708 if (GET_CODE (args
[i
].reg
) == PARALLEL
)
710 tree type
= TREE_TYPE (args
[i
].tree_value
);
711 args
[i
].parallel_value
712 = emit_group_load_into_temps (args
[i
].reg
, args
[i
].value
,
713 type
, int_size_in_bytes (type
));
716 /* If the value is expensive, and we are inside an appropriately
717 short loop, put the value into a pseudo and then put the pseudo
720 For small register classes, also do this if this call uses
721 register parameters. This is to avoid reload conflicts while
722 loading the parameters registers. */
724 else if ((! (REG_P (args
[i
].value
)
725 || (GET_CODE (args
[i
].value
) == SUBREG
726 && REG_P (SUBREG_REG (args
[i
].value
)))))
727 && args
[i
].mode
!= BLKmode
728 && rtx_cost (args
[i
].value
, SET
, optimize_insn_for_speed_p ())
731 && targetm
.small_register_classes_for_mode_p (args
[i
].mode
))
733 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
737 #ifdef REG_PARM_STACK_SPACE
739 /* The argument list is the property of the called routine and it
740 may clobber it. If the fixed area has been used for previous
741 parameters, we must save and restore it. */
744 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
749 /* Compute the boundary of the area that needs to be saved, if any. */
750 high
= reg_parm_stack_space
;
751 #ifdef ARGS_GROW_DOWNWARD
754 if (high
> highest_outgoing_arg_in_use
)
755 high
= highest_outgoing_arg_in_use
;
757 for (low
= 0; low
< high
; low
++)
758 if (stack_usage_map
[low
] != 0)
761 enum machine_mode save_mode
;
766 while (stack_usage_map
[--high
] == 0)
770 *high_to_save
= high
;
772 num_to_save
= high
- low
+ 1;
773 save_mode
= mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
775 /* If we don't have the required alignment, must do this
777 if ((low
& (MIN (GET_MODE_SIZE (save_mode
),
778 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
781 #ifdef ARGS_GROW_DOWNWARD
786 stack_area
= gen_rtx_MEM (save_mode
,
787 memory_address (save_mode
,
788 plus_constant (argblock
,
791 set_mem_align (stack_area
, PARM_BOUNDARY
);
792 if (save_mode
== BLKmode
)
794 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
795 emit_block_move (validize_mem (save_area
), stack_area
,
796 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
800 save_area
= gen_reg_rtx (save_mode
);
801 emit_move_insn (save_area
, stack_area
);
811 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
813 enum machine_mode save_mode
= GET_MODE (save_area
);
817 #ifdef ARGS_GROW_DOWNWARD
818 delta
= -high_to_save
;
822 stack_area
= gen_rtx_MEM (save_mode
,
823 memory_address (save_mode
,
824 plus_constant (argblock
, delta
)));
825 set_mem_align (stack_area
, PARM_BOUNDARY
);
827 if (save_mode
!= BLKmode
)
828 emit_move_insn (stack_area
, save_area
);
830 emit_block_move (stack_area
, validize_mem (save_area
),
831 GEN_INT (high_to_save
- low_to_save
+ 1),
834 #endif /* REG_PARM_STACK_SPACE */
836 /* If any elements in ARGS refer to parameters that are to be passed in
837 registers, but not in memory, and whose alignment does not permit a
838 direct copy into registers. Copy the values into a group of pseudos
839 which we will later copy into the appropriate hard registers.
841 Pseudos for each unaligned argument will be stored into the array
842 args[argnum].aligned_regs. The caller is responsible for deallocating
843 the aligned_regs array if it is nonzero. */
846 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
850 for (i
= 0; i
< num_actuals
; i
++)
851 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
852 && args
[i
].mode
== BLKmode
853 && MEM_P (args
[i
].value
)
854 && (MEM_ALIGN (args
[i
].value
)
855 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
857 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
858 int endian_correction
= 0;
862 gcc_assert (args
[i
].partial
% UNITS_PER_WORD
== 0);
863 args
[i
].n_aligned_regs
= args
[i
].partial
/ UNITS_PER_WORD
;
867 args
[i
].n_aligned_regs
868 = (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
871 args
[i
].aligned_regs
= XNEWVEC (rtx
, args
[i
].n_aligned_regs
);
873 /* Structures smaller than a word are normally aligned to the
874 least significant byte. On a BYTES_BIG_ENDIAN machine,
875 this means we must skip the empty high order bytes when
876 calculating the bit offset. */
877 if (bytes
< UNITS_PER_WORD
878 #ifdef BLOCK_REG_PADDING
879 && (BLOCK_REG_PADDING (args
[i
].mode
,
880 TREE_TYPE (args
[i
].tree_value
), 1)
886 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
888 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
890 rtx reg
= gen_reg_rtx (word_mode
);
891 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
892 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
894 args
[i
].aligned_regs
[j
] = reg
;
895 word
= extract_bit_field (word
, bitsize
, 0, 1, false, NULL_RTX
,
896 word_mode
, word_mode
);
898 /* There is no need to restrict this code to loading items
899 in TYPE_ALIGN sized hunks. The bitfield instructions can
900 load up entire word sized registers efficiently.
902 ??? This may not be needed anymore.
903 We use to emit a clobber here but that doesn't let later
904 passes optimize the instructions we emit. By storing 0 into
905 the register later passes know the first AND to zero out the
906 bitfield being set in the register is unnecessary. The store
907 of 0 will be deleted as will at least the first AND. */
909 emit_move_insn (reg
, const0_rtx
);
911 bytes
-= bitsize
/ BITS_PER_UNIT
;
912 store_bit_field (reg
, bitsize
, endian_correction
, word_mode
,
918 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
921 NUM_ACTUALS is the total number of parameters.
923 N_NAMED_ARGS is the total number of named arguments.
925 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
928 FNDECL is the tree code for the target of this call (if known)
930 ARGS_SO_FAR holds state needed by the target to know where to place
933 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
934 for arguments which are passed in registers.
936 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
937 and may be modified by this routine.
939 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
940 flags which may may be modified by this routine.
942 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
943 that requires allocation of stack space.
945 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
946 the thunked-to function. */
949 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
950 struct arg_data
*args
,
951 struct args_size
*args_size
,
952 int n_named_args ATTRIBUTE_UNUSED
,
953 tree exp
, tree struct_value_addr_value
,
954 tree fndecl
, tree fntype
,
955 CUMULATIVE_ARGS
*args_so_far
,
956 int reg_parm_stack_space
,
957 rtx
*old_stack_level
, int *old_pending_adj
,
958 int *must_preallocate
, int *ecf_flags
,
959 bool *may_tailcall
, bool call_from_thunk_p
)
961 location_t loc
= EXPR_LOCATION (exp
);
962 /* 1 if scanning parms front to back, -1 if scanning back to front. */
965 /* Count arg position in order args appear. */
970 args_size
->constant
= 0;
973 /* In this loop, we consider args in the order they are written.
974 We fill up ARGS from the front or from the back if necessary
975 so that in any case the first arg to be pushed ends up at the front. */
977 if (PUSH_ARGS_REVERSED
)
979 i
= num_actuals
- 1, inc
= -1;
980 /* In this case, must reverse order of args
981 so that we compute and push the last arg first. */
988 /* First fill in the actual arguments in the ARGS array, splitting
989 complex arguments if necessary. */
992 call_expr_arg_iterator iter
;
995 if (struct_value_addr_value
)
997 args
[j
].tree_value
= struct_value_addr_value
;
1000 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
1002 tree argtype
= TREE_TYPE (arg
);
1003 if (targetm
.calls
.split_complex_arg
1005 && TREE_CODE (argtype
) == COMPLEX_TYPE
1006 && targetm
.calls
.split_complex_arg (argtype
))
1008 tree subtype
= TREE_TYPE (argtype
);
1009 args
[j
].tree_value
= build1 (REALPART_EXPR
, subtype
, arg
);
1011 args
[j
].tree_value
= build1 (IMAGPART_EXPR
, subtype
, arg
);
1014 args
[j
].tree_value
= arg
;
1019 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1020 for (argpos
= 0; argpos
< num_actuals
; i
+= inc
, argpos
++)
1022 tree type
= TREE_TYPE (args
[i
].tree_value
);
1024 enum machine_mode mode
;
1026 /* Replace erroneous argument with constant zero. */
1027 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1028 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1030 /* If TYPE is a transparent union or record, pass things the way
1031 we would pass the first field of the union or record. We have
1032 already verified that the modes are the same. */
1033 if ((TREE_CODE (type
) == UNION_TYPE
|| TREE_CODE (type
) == RECORD_TYPE
)
1034 && TYPE_TRANSPARENT_AGGR (type
))
1035 type
= TREE_TYPE (first_field (type
));
1037 /* Decide where to pass this arg.
1039 args[i].reg is nonzero if all or part is passed in registers.
1041 args[i].partial is nonzero if part but not all is passed in registers,
1042 and the exact value says how many bytes are passed in registers.
1044 args[i].pass_on_stack is nonzero if the argument must at least be
1045 computed on the stack. It may then be loaded back into registers
1046 if args[i].reg is nonzero.
1048 These decisions are driven by the FUNCTION_... macros and must agree
1049 with those made by function.c. */
1051 /* See if this argument should be passed by invisible reference. */
1052 if (pass_by_reference (args_so_far
, TYPE_MODE (type
),
1053 type
, argpos
< n_named_args
))
1059 = reference_callee_copied (args_so_far
, TYPE_MODE (type
),
1060 type
, argpos
< n_named_args
);
1062 /* If we're compiling a thunk, pass through invisible references
1063 instead of making a copy. */
1064 if (call_from_thunk_p
1066 && !TREE_ADDRESSABLE (type
)
1067 && (base
= get_base_address (args
[i
].tree_value
))
1068 && TREE_CODE (base
) != SSA_NAME
1069 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
)))))
1071 /* We can't use sibcalls if a callee-copied argument is
1072 stored in the current function's frame. */
1073 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
1074 *may_tailcall
= false;
1076 args
[i
].tree_value
= build_fold_addr_expr_loc (loc
,
1077 args
[i
].tree_value
);
1078 type
= TREE_TYPE (args
[i
].tree_value
);
1080 if (*ecf_flags
& ECF_CONST
)
1081 *ecf_flags
&= ~(ECF_CONST
| ECF_LOOPING_CONST_OR_PURE
);
1085 /* We make a copy of the object and pass the address to the
1086 function being called. */
1089 if (!COMPLETE_TYPE_P (type
)
1090 || TREE_CODE (TYPE_SIZE_UNIT (type
)) != INTEGER_CST
1091 || (flag_stack_check
== GENERIC_STACK_CHECK
1092 && compare_tree_int (TYPE_SIZE_UNIT (type
),
1093 STACK_CHECK_MAX_VAR_SIZE
) > 0))
1095 /* This is a variable-sized object. Make space on the stack
1097 rtx size_rtx
= expr_size (args
[i
].tree_value
);
1099 if (*old_stack_level
== 0)
1101 emit_stack_save (SAVE_BLOCK
, old_stack_level
);
1102 *old_pending_adj
= pending_stack_adjust
;
1103 pending_stack_adjust
= 0;
1106 /* We can pass TRUE as the 4th argument because we just
1107 saved the stack pointer and will restore it right after
1109 copy
= allocate_dynamic_stack_space (size_rtx
,
1113 copy
= gen_rtx_MEM (BLKmode
, copy
);
1114 set_mem_attributes (copy
, type
, 1);
1117 copy
= assign_temp (type
, 0, 1, 0);
1119 store_expr (args
[i
].tree_value
, copy
, 0, false);
1121 /* Just change the const function to pure and then let
1122 the next test clear the pure based on
1124 if (*ecf_flags
& ECF_CONST
)
1126 *ecf_flags
&= ~ECF_CONST
;
1127 *ecf_flags
|= ECF_PURE
;
1130 if (!callee_copies
&& *ecf_flags
& ECF_PURE
)
1131 *ecf_flags
&= ~(ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
1134 = build_fold_addr_expr_loc (loc
, make_tree (type
, copy
));
1135 type
= TREE_TYPE (args
[i
].tree_value
);
1136 *may_tailcall
= false;
1140 unsignedp
= TYPE_UNSIGNED (type
);
1141 mode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
1142 fndecl
? TREE_TYPE (fndecl
) : fntype
, 0);
1144 args
[i
].unsignedp
= unsignedp
;
1145 args
[i
].mode
= mode
;
1147 args
[i
].reg
= targetm
.calls
.function_arg (args_so_far
, mode
, type
,
1148 argpos
< n_named_args
);
1150 /* If this is a sibling call and the machine has register windows, the
1151 register window has to be unwinded before calling the routine, so
1152 arguments have to go into the incoming registers. */
1153 if (targetm
.calls
.function_incoming_arg
!= targetm
.calls
.function_arg
)
1154 args
[i
].tail_call_reg
1155 = targetm
.calls
.function_incoming_arg (args_so_far
, mode
, type
,
1156 argpos
< n_named_args
);
1158 args
[i
].tail_call_reg
= args
[i
].reg
;
1162 = targetm
.calls
.arg_partial_bytes (args_so_far
, mode
, type
,
1163 argpos
< n_named_args
);
1165 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (mode
, type
);
1167 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1168 it means that we are to pass this arg in the register(s) designated
1169 by the PARALLEL, but also to pass it in the stack. */
1170 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1171 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1172 args
[i
].pass_on_stack
= 1;
1174 /* If this is an addressable type, we must preallocate the stack
1175 since we must evaluate the object into its final location.
1177 If this is to be passed in both registers and the stack, it is simpler
1179 if (TREE_ADDRESSABLE (type
)
1180 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1181 *must_preallocate
= 1;
1183 /* Compute the stack-size of this argument. */
1184 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1185 || reg_parm_stack_space
> 0
1186 || args
[i
].pass_on_stack
)
1187 locate_and_pad_parm (mode
, type
,
1188 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1193 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
1194 fndecl
, args_size
, &args
[i
].locate
);
1195 #ifdef BLOCK_REG_PADDING
1197 /* The argument is passed entirely in registers. See at which
1198 end it should be padded. */
1199 args
[i
].locate
.where_pad
=
1200 BLOCK_REG_PADDING (mode
, type
,
1201 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
1204 /* Update ARGS_SIZE, the total stack space for args so far. */
1206 args_size
->constant
+= args
[i
].locate
.size
.constant
;
1207 if (args
[i
].locate
.size
.var
)
1208 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
1210 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1211 have been used, etc. */
1213 targetm
.calls
.function_arg_advance (args_so_far
, TYPE_MODE (type
),
1214 type
, argpos
< n_named_args
);
1218 /* Update ARGS_SIZE to contain the total size for the argument block.
1219 Return the original constant component of the argument block's size.
1221 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1222 for arguments passed in registers. */
1225 compute_argument_block_size (int reg_parm_stack_space
,
1226 struct args_size
*args_size
,
1227 tree fndecl ATTRIBUTE_UNUSED
,
1228 tree fntype ATTRIBUTE_UNUSED
,
1229 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
1231 int unadjusted_args_size
= args_size
->constant
;
1233 /* For accumulate outgoing args mode we don't need to align, since the frame
1234 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1235 backends from generating misaligned frame sizes. */
1236 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1237 preferred_stack_boundary
= STACK_BOUNDARY
;
1239 /* Compute the actual size of the argument block required. The variable
1240 and constant sizes must be combined, the size may have to be rounded,
1241 and there may be a minimum required size. */
1245 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1246 args_size
->constant
= 0;
1248 preferred_stack_boundary
/= BITS_PER_UNIT
;
1249 if (preferred_stack_boundary
> 1)
1251 /* We don't handle this case yet. To handle it correctly we have
1252 to add the delta, round and subtract the delta.
1253 Currently no machine description requires this support. */
1254 gcc_assert (!(stack_pointer_delta
& (preferred_stack_boundary
- 1)));
1255 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1258 if (reg_parm_stack_space
> 0)
1261 = size_binop (MAX_EXPR
, args_size
->var
,
1262 ssize_int (reg_parm_stack_space
));
1264 /* The area corresponding to register parameters is not to count in
1265 the size of the block we need. So make the adjustment. */
1266 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
1268 = size_binop (MINUS_EXPR
, args_size
->var
,
1269 ssize_int (reg_parm_stack_space
));
1274 preferred_stack_boundary
/= BITS_PER_UNIT
;
1275 if (preferred_stack_boundary
< 1)
1276 preferred_stack_boundary
= 1;
1277 args_size
->constant
= (((args_size
->constant
1278 + stack_pointer_delta
1279 + preferred_stack_boundary
- 1)
1280 / preferred_stack_boundary
1281 * preferred_stack_boundary
)
1282 - stack_pointer_delta
);
1284 args_size
->constant
= MAX (args_size
->constant
,
1285 reg_parm_stack_space
);
1287 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
1288 args_size
->constant
-= reg_parm_stack_space
;
1290 return unadjusted_args_size
;
1293 /* Precompute parameters as needed for a function call.
1295 FLAGS is mask of ECF_* constants.
1297 NUM_ACTUALS is the number of arguments.
1299 ARGS is an array containing information for each argument; this
1300 routine fills in the INITIAL_VALUE and VALUE fields for each
1301 precomputed argument. */
1304 precompute_arguments (int num_actuals
, struct arg_data
*args
)
1308 /* If this is a libcall, then precompute all arguments so that we do not
1309 get extraneous instructions emitted as part of the libcall sequence. */
1311 /* If we preallocated the stack space, and some arguments must be passed
1312 on the stack, then we must precompute any parameter which contains a
1313 function call which will store arguments on the stack.
1314 Otherwise, evaluating the parameter may clobber previous parameters
1315 which have already been stored into the stack. (we have code to avoid
1316 such case by saving the outgoing stack arguments, but it results in
1318 if (!ACCUMULATE_OUTGOING_ARGS
)
1321 for (i
= 0; i
< num_actuals
; i
++)
1324 enum machine_mode mode
;
1326 if (TREE_CODE (args
[i
].tree_value
) != CALL_EXPR
)
1329 /* If this is an addressable type, we cannot pre-evaluate it. */
1330 type
= TREE_TYPE (args
[i
].tree_value
);
1331 gcc_assert (!TREE_ADDRESSABLE (type
));
1333 args
[i
].initial_value
= args
[i
].value
1334 = expand_normal (args
[i
].tree_value
);
1336 mode
= TYPE_MODE (type
);
1337 if (mode
!= args
[i
].mode
)
1339 int unsignedp
= args
[i
].unsignedp
;
1341 = convert_modes (args
[i
].mode
, mode
,
1342 args
[i
].value
, args
[i
].unsignedp
);
1344 /* CSE will replace this only if it contains args[i].value
1345 pseudo, so convert it down to the declared mode using
1347 if (REG_P (args
[i
].value
)
1348 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
1349 && promote_mode (type
, mode
, &unsignedp
) != args
[i
].mode
)
1351 args
[i
].initial_value
1352 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1353 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1354 SUBREG_PROMOTED_UNSIGNED_SET (args
[i
].initial_value
,
1361 /* Given the current state of MUST_PREALLOCATE and information about
1362 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1363 compute and return the final value for MUST_PREALLOCATE. */
1366 finalize_must_preallocate (int must_preallocate
, int num_actuals
,
1367 struct arg_data
*args
, struct args_size
*args_size
)
1369 /* See if we have or want to preallocate stack space.
1371 If we would have to push a partially-in-regs parm
1372 before other stack parms, preallocate stack space instead.
1374 If the size of some parm is not a multiple of the required stack
1375 alignment, we must preallocate.
1377 If the total size of arguments that would otherwise create a copy in
1378 a temporary (such as a CALL) is more than half the total argument list
1379 size, preallocation is faster.
1381 Another reason to preallocate is if we have a machine (like the m88k)
1382 where stack alignment is required to be maintained between every
1383 pair of insns, not just when the call is made. However, we assume here
1384 that such machines either do not have push insns (and hence preallocation
1385 would occur anyway) or the problem is taken care of with
1388 if (! must_preallocate
)
1390 int partial_seen
= 0;
1391 int copy_to_evaluate_size
= 0;
1394 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1396 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1398 else if (partial_seen
&& args
[i
].reg
== 0)
1399 must_preallocate
= 1;
1401 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1402 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1403 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1404 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1405 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1406 copy_to_evaluate_size
1407 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1410 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1411 && args_size
->constant
> 0)
1412 must_preallocate
= 1;
1414 return must_preallocate
;
1417 /* If we preallocated stack space, compute the address of each argument
1418 and store it into the ARGS array.
1420 We need not ensure it is a valid memory address here; it will be
1421 validized when it is used.
1423 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1426 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
1430 rtx arg_reg
= argblock
;
1431 int i
, arg_offset
= 0;
1433 if (GET_CODE (argblock
) == PLUS
)
1434 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1436 for (i
= 0; i
< num_actuals
; i
++)
1438 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
1439 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
1441 unsigned int align
, boundary
;
1442 unsigned int units_on_stack
= 0;
1443 enum machine_mode partial_mode
= VOIDmode
;
1445 /* Skip this parm if it will not be passed on the stack. */
1446 if (! args
[i
].pass_on_stack
1448 && args
[i
].partial
== 0)
1451 if (CONST_INT_P (offset
))
1452 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1454 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1456 addr
= plus_constant (addr
, arg_offset
);
1458 if (args
[i
].partial
!= 0)
1460 /* Only part of the parameter is being passed on the stack.
1461 Generate a simple memory reference of the correct size. */
1462 units_on_stack
= args
[i
].locate
.size
.constant
;
1463 partial_mode
= mode_for_size (units_on_stack
* BITS_PER_UNIT
,
1465 args
[i
].stack
= gen_rtx_MEM (partial_mode
, addr
);
1466 set_mem_size (args
[i
].stack
, GEN_INT (units_on_stack
));
1470 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1471 set_mem_attributes (args
[i
].stack
,
1472 TREE_TYPE (args
[i
].tree_value
), 1);
1474 align
= BITS_PER_UNIT
;
1475 boundary
= args
[i
].locate
.boundary
;
1476 if (args
[i
].locate
.where_pad
!= downward
)
1478 else if (CONST_INT_P (offset
))
1480 align
= INTVAL (offset
) * BITS_PER_UNIT
| boundary
;
1481 align
= align
& -align
;
1483 set_mem_align (args
[i
].stack
, align
);
1485 if (CONST_INT_P (slot_offset
))
1486 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1488 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1490 addr
= plus_constant (addr
, arg_offset
);
1492 if (args
[i
].partial
!= 0)
1494 /* Only part of the parameter is being passed on the stack.
1495 Generate a simple memory reference of the correct size.
1497 args
[i
].stack_slot
= gen_rtx_MEM (partial_mode
, addr
);
1498 set_mem_size (args
[i
].stack_slot
, GEN_INT (units_on_stack
));
1502 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1503 set_mem_attributes (args
[i
].stack_slot
,
1504 TREE_TYPE (args
[i
].tree_value
), 1);
1506 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
1508 /* Function incoming arguments may overlap with sibling call
1509 outgoing arguments and we cannot allow reordering of reads
1510 from function arguments with stores to outgoing arguments
1511 of sibling calls. */
1512 set_mem_alias_set (args
[i
].stack
, 0);
1513 set_mem_alias_set (args
[i
].stack_slot
, 0);
1518 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1519 in a call instruction.
1521 FNDECL is the tree node for the target function. For an indirect call
1522 FNDECL will be NULL_TREE.
1524 ADDR is the operand 0 of CALL_EXPR for this call. */
1527 rtx_for_function_call (tree fndecl
, tree addr
)
1531 /* Get the function to call, in the form of RTL. */
1534 /* If this is the first use of the function, see if we need to
1535 make an external definition for it. */
1536 if (!TREE_USED (fndecl
) && fndecl
!= current_function_decl
)
1538 assemble_external (fndecl
);
1539 TREE_USED (fndecl
) = 1;
1542 /* Get a SYMBOL_REF rtx for the function address. */
1543 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1546 /* Generate an rtx (probably a pseudo-register) for the address. */
1549 funexp
= expand_normal (addr
);
1550 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1555 /* Return true if and only if SIZE storage units (usually bytes)
1556 starting from address ADDR overlap with already clobbered argument
1557 area. This function is used to determine if we should give up a
1561 mem_overlaps_already_clobbered_arg_p (rtx addr
, unsigned HOST_WIDE_INT size
)
1565 if (addr
== crtl
->args
.internal_arg_pointer
)
1567 else if (GET_CODE (addr
) == PLUS
1568 && XEXP (addr
, 0) == crtl
->args
.internal_arg_pointer
1569 && CONST_INT_P (XEXP (addr
, 1)))
1570 i
= INTVAL (XEXP (addr
, 1));
1571 /* Return true for arg pointer based indexed addressing. */
1572 else if (GET_CODE (addr
) == PLUS
1573 && (XEXP (addr
, 0) == crtl
->args
.internal_arg_pointer
1574 || XEXP (addr
, 1) == crtl
->args
.internal_arg_pointer
))
1579 #ifdef ARGS_GROW_DOWNWARD
1584 unsigned HOST_WIDE_INT k
;
1586 for (k
= 0; k
< size
; k
++)
1587 if (i
+ k
< stored_args_map
->n_bits
1588 && TEST_BIT (stored_args_map
, i
+ k
))
1595 /* Do the register loads required for any wholly-register parms or any
1596 parms which are passed both on the stack and in a register. Their
1597 expressions were already evaluated.
1599 Mark all register-parms as living through the call, putting these USE
1600 insns in the CALL_INSN_FUNCTION_USAGE field.
1602 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1603 checking, setting *SIBCALL_FAILURE if appropriate. */
1606 load_register_parameters (struct arg_data
*args
, int num_actuals
,
1607 rtx
*call_fusage
, int flags
, int is_sibcall
,
1608 int *sibcall_failure
)
1612 for (i
= 0; i
< num_actuals
; i
++)
1614 rtx reg
= ((flags
& ECF_SIBCALL
)
1615 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1618 int partial
= args
[i
].partial
;
1621 rtx before_arg
= get_last_insn ();
1622 /* Set non-negative if we must move a word at a time, even if
1623 just one word (e.g, partial == 4 && mode == DFmode). Set
1624 to -1 if we just use a normal move insn. This value can be
1625 zero if the argument is a zero size structure. */
1627 if (GET_CODE (reg
) == PARALLEL
)
1631 gcc_assert (partial
% UNITS_PER_WORD
== 0);
1632 nregs
= partial
/ UNITS_PER_WORD
;
1634 else if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
)
1636 size
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1637 nregs
= (size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1640 size
= GET_MODE_SIZE (args
[i
].mode
);
1642 /* Handle calls that pass values in multiple non-contiguous
1643 locations. The Irix 6 ABI has examples of this. */
1645 if (GET_CODE (reg
) == PARALLEL
)
1646 emit_group_move (reg
, args
[i
].parallel_value
);
1648 /* If simple case, just do move. If normal partial, store_one_arg
1649 has already loaded the register for us. In all other cases,
1650 load the register(s) from memory. */
1652 else if (nregs
== -1)
1654 emit_move_insn (reg
, args
[i
].value
);
1655 #ifdef BLOCK_REG_PADDING
1656 /* Handle case where we have a value that needs shifting
1657 up to the msb. eg. a QImode value and we're padding
1658 upward on a BYTES_BIG_ENDIAN machine. */
1659 if (size
< UNITS_PER_WORD
1660 && (args
[i
].locate
.where_pad
1661 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
1664 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1666 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1667 report the whole reg as used. Strictly speaking, the
1668 call only uses SIZE bytes at the msb end, but it doesn't
1669 seem worth generating rtl to say that. */
1670 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
1671 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
1672 build_int_cst (NULL_TREE
, shift
),
1675 emit_move_insn (reg
, x
);
1680 /* If we have pre-computed the values to put in the registers in
1681 the case of non-aligned structures, copy them in now. */
1683 else if (args
[i
].n_aligned_regs
!= 0)
1684 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1685 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1686 args
[i
].aligned_regs
[j
]);
1688 else if (partial
== 0 || args
[i
].pass_on_stack
)
1690 rtx mem
= validize_mem (args
[i
].value
);
1692 /* Check for overlap with already clobbered argument area,
1693 providing that this has non-zero size. */
1696 || mem_overlaps_already_clobbered_arg_p
1697 (XEXP (args
[i
].value
, 0), size
)))
1698 *sibcall_failure
= 1;
1700 /* Handle a BLKmode that needs shifting. */
1701 if (nregs
== 1 && size
< UNITS_PER_WORD
1702 #ifdef BLOCK_REG_PADDING
1703 && args
[i
].locate
.where_pad
== downward
1709 rtx tem
= operand_subword_force (mem
, 0, args
[i
].mode
);
1710 rtx ri
= gen_rtx_REG (word_mode
, REGNO (reg
));
1711 rtx x
= gen_reg_rtx (word_mode
);
1712 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1713 enum tree_code dir
= BYTES_BIG_ENDIAN
? RSHIFT_EXPR
1716 emit_move_insn (x
, tem
);
1717 x
= expand_shift (dir
, word_mode
, x
,
1718 build_int_cst (NULL_TREE
, shift
),
1721 emit_move_insn (ri
, x
);
1724 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
1727 /* When a parameter is a block, and perhaps in other cases, it is
1728 possible that it did a load from an argument slot that was
1729 already clobbered. */
1731 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
1732 *sibcall_failure
= 1;
1734 /* Handle calls that pass values in multiple non-contiguous
1735 locations. The Irix 6 ABI has examples of this. */
1736 if (GET_CODE (reg
) == PARALLEL
)
1737 use_group_regs (call_fusage
, reg
);
1738 else if (nregs
== -1)
1739 use_reg (call_fusage
, reg
);
1741 use_regs (call_fusage
, REGNO (reg
), nregs
);
1746 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1747 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1748 bytes, then we would need to push some additional bytes to pad the
1749 arguments. So, we compute an adjust to the stack pointer for an
1750 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1751 bytes. Then, when the arguments are pushed the stack will be perfectly
1752 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1753 be popped after the call. Returns the adjustment. */
1756 combine_pending_stack_adjustment_and_call (int unadjusted_args_size
,
1757 struct args_size
*args_size
,
1758 unsigned int preferred_unit_stack_boundary
)
1760 /* The number of bytes to pop so that the stack will be
1761 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1762 HOST_WIDE_INT adjustment
;
1763 /* The alignment of the stack after the arguments are pushed, if we
1764 just pushed the arguments without adjust the stack here. */
1765 unsigned HOST_WIDE_INT unadjusted_alignment
;
1767 unadjusted_alignment
1768 = ((stack_pointer_delta
+ unadjusted_args_size
)
1769 % preferred_unit_stack_boundary
);
1771 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1772 as possible -- leaving just enough left to cancel out the
1773 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1774 PENDING_STACK_ADJUST is non-negative, and congruent to
1775 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1777 /* Begin by trying to pop all the bytes. */
1778 unadjusted_alignment
1779 = (unadjusted_alignment
1780 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1781 adjustment
= pending_stack_adjust
;
1782 /* Push enough additional bytes that the stack will be aligned
1783 after the arguments are pushed. */
1784 if (preferred_unit_stack_boundary
> 1)
1786 if (unadjusted_alignment
> 0)
1787 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1789 adjustment
+= unadjusted_alignment
;
1792 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1793 bytes after the call. The right number is the entire
1794 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1795 by the arguments in the first place. */
1797 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1802 /* Scan X expression if it does not dereference any argument slots
1803 we already clobbered by tail call arguments (as noted in stored_args_map
1805 Return nonzero if X expression dereferences such argument slots,
1809 check_sibcall_argument_overlap_1 (rtx x
)
1818 code
= GET_CODE (x
);
1821 return mem_overlaps_already_clobbered_arg_p (XEXP (x
, 0),
1822 GET_MODE_SIZE (GET_MODE (x
)));
1824 /* Scan all subexpressions. */
1825 fmt
= GET_RTX_FORMAT (code
);
1826 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
1830 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
1833 else if (*fmt
== 'E')
1835 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
1836 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
1843 /* Scan sequence after INSN if it does not dereference any argument slots
1844 we already clobbered by tail call arguments (as noted in stored_args_map
1845 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1846 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1847 should be 0). Return nonzero if sequence after INSN dereferences such argument
1848 slots, zero otherwise. */
1851 check_sibcall_argument_overlap (rtx insn
, struct arg_data
*arg
, int mark_stored_args_map
)
1855 if (insn
== NULL_RTX
)
1856 insn
= get_insns ();
1858 insn
= NEXT_INSN (insn
);
1860 for (; insn
; insn
= NEXT_INSN (insn
))
1862 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
1865 if (mark_stored_args_map
)
1867 #ifdef ARGS_GROW_DOWNWARD
1868 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
1870 low
= arg
->locate
.slot_offset
.constant
;
1873 for (high
= low
+ arg
->locate
.size
.constant
; low
< high
; low
++)
1874 SET_BIT (stored_args_map
, low
);
1876 return insn
!= NULL_RTX
;
1879 /* Given that a function returns a value of mode MODE at the most
1880 significant end of hard register VALUE, shift VALUE left or right
1881 as specified by LEFT_P. Return true if some action was needed. */
1884 shift_return_value (enum machine_mode mode
, bool left_p
, rtx value
)
1886 HOST_WIDE_INT shift
;
1888 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
1889 shift
= GET_MODE_BITSIZE (GET_MODE (value
)) - GET_MODE_BITSIZE (mode
);
1893 /* Use ashr rather than lshr for right shifts. This is for the benefit
1894 of the MIPS port, which requires SImode values to be sign-extended
1895 when stored in 64-bit registers. */
1896 if (!force_expand_binop (GET_MODE (value
), left_p
? ashl_optab
: ashr_optab
,
1897 value
, GEN_INT (shift
), value
, 1, OPTAB_WIDEN
))
1902 /* If X is a likely-spilled register value, copy it to a pseudo
1903 register and return that register. Return X otherwise. */
1906 avoid_likely_spilled_reg (rtx x
)
1911 && HARD_REGISTER_P (x
)
1912 && targetm
.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x
))))
1914 /* Make sure that we generate a REG rather than a CONCAT.
1915 Moves into CONCATs can need nontrivial instructions,
1916 and the whole point of this function is to avoid
1917 using the hard register directly in such a situation. */
1918 generating_concat_p
= 0;
1919 new_rtx
= gen_reg_rtx (GET_MODE (x
));
1920 generating_concat_p
= 1;
1921 emit_move_insn (new_rtx
, x
);
1927 /* Generate all the code for a CALL_EXPR exp
1928 and return an rtx for its value.
1929 Store the value in TARGET (specified as an rtx) if convenient.
1930 If the value is stored in TARGET then TARGET is returned.
1931 If IGNORE is nonzero, then we ignore the value of the function call. */
1934 expand_call (tree exp
, rtx target
, int ignore
)
1936 /* Nonzero if we are currently expanding a call. */
1937 static int currently_expanding_call
= 0;
1939 /* RTX for the function to be called. */
1941 /* Sequence of insns to perform a normal "call". */
1942 rtx normal_call_insns
= NULL_RTX
;
1943 /* Sequence of insns to perform a tail "call". */
1944 rtx tail_call_insns
= NULL_RTX
;
1945 /* Data type of the function. */
1947 tree type_arg_types
;
1949 /* Declaration of the function being called,
1950 or 0 if the function is computed (not known by name). */
1952 /* The type of the function being called. */
1954 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
1957 /* Register in which non-BLKmode value will be returned,
1958 or 0 if no value or if value is BLKmode. */
1960 /* Address where we should return a BLKmode value;
1961 0 if value not BLKmode. */
1962 rtx structure_value_addr
= 0;
1963 /* Nonzero if that address is being passed by treating it as
1964 an extra, implicit first parameter. Otherwise,
1965 it is passed by being copied directly into struct_value_rtx. */
1966 int structure_value_addr_parm
= 0;
1967 /* Holds the value of implicit argument for the struct value. */
1968 tree structure_value_addr_value
= NULL_TREE
;
1969 /* Size of aggregate value wanted, or zero if none wanted
1970 or if we are using the non-reentrant PCC calling convention
1971 or expecting the value in registers. */
1972 HOST_WIDE_INT struct_value_size
= 0;
1973 /* Nonzero if called function returns an aggregate in memory PCC style,
1974 by returning the address of where to find it. */
1975 int pcc_struct_value
= 0;
1976 rtx struct_value
= 0;
1978 /* Number of actual parameters in this call, including struct value addr. */
1980 /* Number of named args. Args after this are anonymous ones
1981 and they must all go on the stack. */
1983 /* Number of complex actual arguments that need to be split. */
1984 int num_complex_actuals
= 0;
1986 /* Vector of information about each argument.
1987 Arguments are numbered in the order they will be pushed,
1988 not the order they are written. */
1989 struct arg_data
*args
;
1991 /* Total size in bytes of all the stack-parms scanned so far. */
1992 struct args_size args_size
;
1993 struct args_size adjusted_args_size
;
1994 /* Size of arguments before any adjustments (such as rounding). */
1995 int unadjusted_args_size
;
1996 /* Data on reg parms scanned so far. */
1997 CUMULATIVE_ARGS args_so_far
;
1998 /* Nonzero if a reg parm has been scanned. */
2000 /* Nonzero if this is an indirect function call. */
2002 /* Nonzero if we must avoid push-insns in the args for this call.
2003 If stack space is allocated for register parameters, but not by the
2004 caller, then it is preallocated in the fixed part of the stack frame.
2005 So the entire argument block must then be preallocated (i.e., we
2006 ignore PUSH_ROUNDING in that case). */
2008 int must_preallocate
= !PUSH_ARGS
;
2010 /* Size of the stack reserved for parameter registers. */
2011 int reg_parm_stack_space
= 0;
2013 /* Address of space preallocated for stack parms
2014 (on machines that lack push insns), or 0 if space not preallocated. */
2017 /* Mask of ECF_ flags. */
2019 #ifdef REG_PARM_STACK_SPACE
2020 /* Define the boundary of the register parm stack space that needs to be
2022 int low_to_save
, high_to_save
;
2023 rtx save_area
= 0; /* Place that it is saved */
2026 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
2027 char *initial_stack_usage_map
= stack_usage_map
;
2028 char *stack_usage_map_buf
= NULL
;
2030 int old_stack_allocated
;
2032 /* State variables to track stack modifications. */
2033 rtx old_stack_level
= 0;
2034 int old_stack_arg_under_construction
= 0;
2035 int old_pending_adj
= 0;
2036 int old_inhibit_defer_pop
= inhibit_defer_pop
;
2038 /* Some stack pointer alterations we make are performed via
2039 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2040 which we then also need to save/restore along the way. */
2041 int old_stack_pointer_delta
= 0;
2044 tree addr
= CALL_EXPR_FN (exp
);
2046 /* The alignment of the stack, in bits. */
2047 unsigned HOST_WIDE_INT preferred_stack_boundary
;
2048 /* The alignment of the stack, in bytes. */
2049 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
2050 /* The static chain value to use for this call. */
2051 rtx static_chain_value
;
2052 /* See if this is "nothrow" function call. */
2053 if (TREE_NOTHROW (exp
))
2054 flags
|= ECF_NOTHROW
;
2056 /* See if we can find a DECL-node for the actual function, and get the
2057 function attributes (flags) from the function decl or type node. */
2058 fndecl
= get_callee_fndecl (exp
);
2061 fntype
= TREE_TYPE (fndecl
);
2062 flags
|= flags_from_decl_or_type (fndecl
);
2066 fntype
= TREE_TYPE (TREE_TYPE (addr
));
2067 flags
|= flags_from_decl_or_type (fntype
);
2069 rettype
= TREE_TYPE (exp
);
2071 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
2073 /* Warn if this value is an aggregate type,
2074 regardless of which calling convention we are using for it. */
2075 if (AGGREGATE_TYPE_P (rettype
))
2076 warning (OPT_Waggregate_return
, "function call has aggregate value");
2078 /* If the result of a non looping pure or const function call is
2079 ignored (or void), and none of its arguments are volatile, we can
2080 avoid expanding the call and just evaluate the arguments for
2082 if ((flags
& (ECF_CONST
| ECF_PURE
))
2083 && (!(flags
& ECF_LOOPING_CONST_OR_PURE
))
2084 && (ignore
|| target
== const0_rtx
2085 || TYPE_MODE (rettype
) == VOIDmode
))
2087 bool volatilep
= false;
2089 call_expr_arg_iterator iter
;
2091 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2092 if (TREE_THIS_VOLATILE (arg
))
2100 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2101 expand_expr (arg
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
2106 #ifdef REG_PARM_STACK_SPACE
2107 reg_parm_stack_space
= REG_PARM_STACK_SPACE (!fndecl
? fntype
: fndecl
);
2110 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
2111 && reg_parm_stack_space
> 0 && PUSH_ARGS
)
2112 must_preallocate
= 1;
2114 /* Set up a place to return a structure. */
2116 /* Cater to broken compilers. */
2117 if (aggregate_value_p (exp
, fntype
))
2119 /* This call returns a big structure. */
2120 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
2122 #ifdef PCC_STATIC_STRUCT_RETURN
2124 pcc_struct_value
= 1;
2126 #else /* not PCC_STATIC_STRUCT_RETURN */
2128 struct_value_size
= int_size_in_bytes (rettype
);
2130 if (target
&& MEM_P (target
) && CALL_EXPR_RETURN_SLOT_OPT (exp
))
2131 structure_value_addr
= XEXP (target
, 0);
2134 /* For variable-sized objects, we must be called with a target
2135 specified. If we were to allocate space on the stack here,
2136 we would have no way of knowing when to free it. */
2137 rtx d
= assign_temp (rettype
, 0, 1, 1);
2139 mark_temp_addr_taken (d
);
2140 structure_value_addr
= XEXP (d
, 0);
2144 #endif /* not PCC_STATIC_STRUCT_RETURN */
2147 /* Figure out the amount to which the stack should be aligned. */
2148 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2151 struct cgraph_rtl_info
*i
= cgraph_rtl_info (fndecl
);
2152 /* Without automatic stack alignment, we can't increase preferred
2153 stack boundary. With automatic stack alignment, it is
2154 unnecessary since unless we can guarantee that all callers will
2155 align the outgoing stack properly, callee has to align its
2158 && i
->preferred_incoming_stack_boundary
2159 && i
->preferred_incoming_stack_boundary
< preferred_stack_boundary
)
2160 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
2163 /* Operand 0 is a pointer-to-function; get the type of the function. */
2164 funtype
= TREE_TYPE (addr
);
2165 gcc_assert (POINTER_TYPE_P (funtype
));
2166 funtype
= TREE_TYPE (funtype
);
2168 /* Count whether there are actual complex arguments that need to be split
2169 into their real and imaginary parts. Munge the type_arg_types
2170 appropriately here as well. */
2171 if (targetm
.calls
.split_complex_arg
)
2173 call_expr_arg_iterator iter
;
2175 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2177 tree type
= TREE_TYPE (arg
);
2178 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
2179 && targetm
.calls
.split_complex_arg (type
))
2180 num_complex_actuals
++;
2182 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
2185 type_arg_types
= TYPE_ARG_TYPES (funtype
);
2187 if (flags
& ECF_MAY_BE_ALLOCA
)
2188 cfun
->calls_alloca
= 1;
2190 /* If struct_value_rtx is 0, it means pass the address
2191 as if it were an extra parameter. Put the argument expression
2192 in structure_value_addr_value. */
2193 if (structure_value_addr
&& struct_value
== 0)
2195 /* If structure_value_addr is a REG other than
2196 virtual_outgoing_args_rtx, we can use always use it. If it
2197 is not a REG, we must always copy it into a register.
2198 If it is virtual_outgoing_args_rtx, we must copy it to another
2199 register in some cases. */
2200 rtx temp
= (!REG_P (structure_value_addr
)
2201 || (ACCUMULATE_OUTGOING_ARGS
2202 && stack_arg_under_construction
2203 && structure_value_addr
== virtual_outgoing_args_rtx
)
2204 ? copy_addr_to_reg (convert_memory_address
2205 (Pmode
, structure_value_addr
))
2206 : structure_value_addr
);
2208 structure_value_addr_value
=
2209 make_tree (build_pointer_type (TREE_TYPE (funtype
)), temp
);
2210 structure_value_addr_parm
= 1;
2213 /* Count the arguments and set NUM_ACTUALS. */
2215 call_expr_nargs (exp
) + num_complex_actuals
+ structure_value_addr_parm
;
2217 /* Compute number of named args.
2218 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2220 if (type_arg_types
!= 0)
2222 = (list_length (type_arg_types
)
2223 /* Count the struct value address, if it is passed as a parm. */
2224 + structure_value_addr_parm
);
2226 /* If we know nothing, treat all args as named. */
2227 n_named_args
= num_actuals
;
2229 /* Start updating where the next arg would go.
2231 On some machines (such as the PA) indirect calls have a different
2232 calling convention than normal calls. The fourth argument in
2233 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2235 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
2237 /* Now possibly adjust the number of named args.
2238 Normally, don't include the last named arg if anonymous args follow.
2239 We do include the last named arg if
2240 targetm.calls.strict_argument_naming() returns nonzero.
2241 (If no anonymous args follow, the result of list_length is actually
2242 one too large. This is harmless.)
2244 If targetm.calls.pretend_outgoing_varargs_named() returns
2245 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2246 this machine will be able to place unnamed args that were passed
2247 in registers into the stack. So treat all args as named. This
2248 allows the insns emitting for a specific argument list to be
2249 independent of the function declaration.
2251 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2252 we do not have any reliable way to pass unnamed args in
2253 registers, so we must force them into memory. */
2255 if (type_arg_types
!= 0
2256 && targetm
.calls
.strict_argument_naming (&args_so_far
))
2258 else if (type_arg_types
!= 0
2259 && ! targetm
.calls
.pretend_outgoing_varargs_named (&args_so_far
))
2260 /* Don't include the last named arg. */
2263 /* Treat all args as named. */
2264 n_named_args
= num_actuals
;
2266 /* Make a vector to hold all the information about each arg. */
2267 args
= XALLOCAVEC (struct arg_data
, num_actuals
);
2268 memset (args
, 0, num_actuals
* sizeof (struct arg_data
));
2270 /* Build up entries in the ARGS array, compute the size of the
2271 arguments into ARGS_SIZE, etc. */
2272 initialize_argument_information (num_actuals
, args
, &args_size
,
2274 structure_value_addr_value
, fndecl
, fntype
,
2275 &args_so_far
, reg_parm_stack_space
,
2276 &old_stack_level
, &old_pending_adj
,
2277 &must_preallocate
, &flags
,
2278 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
2281 must_preallocate
= 1;
2283 /* Now make final decision about preallocating stack space. */
2284 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2288 /* If the structure value address will reference the stack pointer, we
2289 must stabilize it. We don't need to do this if we know that we are
2290 not going to adjust the stack pointer in processing this call. */
2292 if (structure_value_addr
2293 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2294 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2295 structure_value_addr
))
2297 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2298 structure_value_addr
= copy_to_reg (structure_value_addr
);
2300 /* Tail calls can make things harder to debug, and we've traditionally
2301 pushed these optimizations into -O2. Don't try if we're already
2302 expanding a call, as that means we're an argument. Don't try if
2303 there's cleanups, as we know there's code to follow the call. */
2305 if (currently_expanding_call
++ != 0
2306 || !flag_optimize_sibling_calls
2308 || dbg_cnt (tail_call
) == false)
2311 /* Rest of purposes for tail call optimizations to fail. */
2313 #ifdef HAVE_sibcall_epilogue
2314 !HAVE_sibcall_epilogue
2319 /* Doing sibling call optimization needs some work, since
2320 structure_value_addr can be allocated on the stack.
2321 It does not seem worth the effort since few optimizable
2322 sibling calls will return a structure. */
2323 || structure_value_addr
!= NULL_RTX
2324 #ifdef REG_PARM_STACK_SPACE
2325 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2326 || (OUTGOING_REG_PARM_STACK_SPACE (funtype
)
2327 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl
)))
2328 || (reg_parm_stack_space
!= REG_PARM_STACK_SPACE (fndecl
))
2330 /* Check whether the target is able to optimize the call
2332 || !targetm
.function_ok_for_sibcall (fndecl
, exp
)
2333 /* Functions that do not return exactly once may not be sibcall
2335 || (flags
& (ECF_RETURNS_TWICE
| ECF_NORETURN
))
2336 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
)))
2337 /* If the called function is nested in the current one, it might access
2338 some of the caller's arguments, but could clobber them beforehand if
2339 the argument areas are shared. */
2340 || (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
2341 /* If this function requires more stack slots than the current
2342 function, we cannot change it into a sibling call.
2343 crtl->args.pretend_args_size is not part of the
2344 stack allocated by our caller. */
2345 || args_size
.constant
> (crtl
->args
.size
2346 - crtl
->args
.pretend_args_size
)
2347 /* If the callee pops its own arguments, then it must pop exactly
2348 the same number of arguments as the current function. */
2349 || (targetm
.calls
.return_pops_args (fndecl
, funtype
, args_size
.constant
)
2350 != targetm
.calls
.return_pops_args (current_function_decl
,
2351 TREE_TYPE (current_function_decl
),
2353 || !lang_hooks
.decls
.ok_for_sibcall (fndecl
))
2356 /* Check if caller and callee disagree in promotion of function
2360 enum machine_mode caller_mode
, caller_promoted_mode
;
2361 enum machine_mode callee_mode
, callee_promoted_mode
;
2362 int caller_unsignedp
, callee_unsignedp
;
2363 tree caller_res
= DECL_RESULT (current_function_decl
);
2365 caller_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (caller_res
));
2366 caller_mode
= DECL_MODE (caller_res
);
2367 callee_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (funtype
));
2368 callee_mode
= TYPE_MODE (TREE_TYPE (funtype
));
2369 caller_promoted_mode
2370 = promote_function_mode (TREE_TYPE (caller_res
), caller_mode
,
2372 TREE_TYPE (current_function_decl
), 1);
2373 callee_promoted_mode
2374 = promote_function_mode (TREE_TYPE (funtype
), callee_mode
,
2377 if (caller_mode
!= VOIDmode
2378 && (caller_promoted_mode
!= callee_promoted_mode
2379 || ((caller_mode
!= caller_promoted_mode
2380 || callee_mode
!= callee_promoted_mode
)
2381 && (caller_unsignedp
!= callee_unsignedp
2382 || GET_MODE_BITSIZE (caller_mode
)
2383 < GET_MODE_BITSIZE (callee_mode
)))))
2387 /* Ensure current function's preferred stack boundary is at least
2388 what we need. Stack alignment may also increase preferred stack
2390 if (crtl
->preferred_stack_boundary
< preferred_stack_boundary
)
2391 crtl
->preferred_stack_boundary
= preferred_stack_boundary
;
2393 preferred_stack_boundary
= crtl
->preferred_stack_boundary
;
2395 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2397 /* We want to make two insn chains; one for a sibling call, the other
2398 for a normal call. We will select one of the two chains after
2399 initial RTL generation is complete. */
2400 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
2402 int sibcall_failure
= 0;
2403 /* We want to emit any pending stack adjustments before the tail
2404 recursion "call". That way we know any adjustment after the tail
2405 recursion call can be ignored if we indeed use the tail
2407 int save_pending_stack_adjust
= 0;
2408 int save_stack_pointer_delta
= 0;
2410 rtx before_call
, next_arg_reg
, after_args
;
2414 /* State variables we need to save and restore between
2416 save_pending_stack_adjust
= pending_stack_adjust
;
2417 save_stack_pointer_delta
= stack_pointer_delta
;
2420 flags
&= ~ECF_SIBCALL
;
2422 flags
|= ECF_SIBCALL
;
2424 /* Other state variables that we must reinitialize each time
2425 through the loop (that are not initialized by the loop itself). */
2429 /* Start a new sequence for the normal call case.
2431 From this point on, if the sibling call fails, we want to set
2432 sibcall_failure instead of continuing the loop. */
2435 /* Don't let pending stack adjusts add up to too much.
2436 Also, do all pending adjustments now if there is any chance
2437 this might be a call to alloca or if we are expanding a sibling
2439 Also do the adjustments before a throwing call, otherwise
2440 exception handling can fail; PR 19225. */
2441 if (pending_stack_adjust
>= 32
2442 || (pending_stack_adjust
> 0
2443 && (flags
& ECF_MAY_BE_ALLOCA
))
2444 || (pending_stack_adjust
> 0
2445 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
2447 do_pending_stack_adjust ();
2449 /* Precompute any arguments as needed. */
2451 precompute_arguments (num_actuals
, args
);
2453 /* Now we are about to start emitting insns that can be deleted
2454 if a libcall is deleted. */
2455 if (pass
&& (flags
& ECF_MALLOC
))
2458 if (pass
== 0 && crtl
->stack_protect_guard
)
2459 stack_protect_epilogue ();
2461 adjusted_args_size
= args_size
;
2462 /* Compute the actual size of the argument block required. The variable
2463 and constant sizes must be combined, the size may have to be rounded,
2464 and there may be a minimum required size. When generating a sibcall
2465 pattern, do not round up, since we'll be re-using whatever space our
2467 unadjusted_args_size
2468 = compute_argument_block_size (reg_parm_stack_space
,
2469 &adjusted_args_size
,
2472 : preferred_stack_boundary
));
2474 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2476 /* The argument block when performing a sibling call is the
2477 incoming argument block. */
2480 argblock
= crtl
->args
.internal_arg_pointer
;
2482 #ifdef STACK_GROWS_DOWNWARD
2483 = plus_constant (argblock
, crtl
->args
.pretend_args_size
);
2485 = plus_constant (argblock
, -crtl
->args
.pretend_args_size
);
2487 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2488 sbitmap_zero (stored_args_map
);
2491 /* If we have no actual push instructions, or shouldn't use them,
2492 make space for all args right now. */
2493 else if (adjusted_args_size
.var
!= 0)
2495 if (old_stack_level
== 0)
2497 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
2498 old_stack_pointer_delta
= stack_pointer_delta
;
2499 old_pending_adj
= pending_stack_adjust
;
2500 pending_stack_adjust
= 0;
2501 /* stack_arg_under_construction says whether a stack arg is
2502 being constructed at the old stack level. Pushing the stack
2503 gets a clean outgoing argument block. */
2504 old_stack_arg_under_construction
= stack_arg_under_construction
;
2505 stack_arg_under_construction
= 0;
2507 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2508 if (flag_stack_usage
)
2509 current_function_has_unbounded_dynamic_stack_size
= 1;
2513 /* Note that we must go through the motions of allocating an argument
2514 block even if the size is zero because we may be storing args
2515 in the area reserved for register arguments, which may be part of
2518 int needed
= adjusted_args_size
.constant
;
2520 /* Store the maximum argument space used. It will be pushed by
2521 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2524 if (needed
> crtl
->outgoing_args_size
)
2525 crtl
->outgoing_args_size
= needed
;
2527 if (must_preallocate
)
2529 if (ACCUMULATE_OUTGOING_ARGS
)
2531 /* Since the stack pointer will never be pushed, it is
2532 possible for the evaluation of a parm to clobber
2533 something we have already written to the stack.
2534 Since most function calls on RISC machines do not use
2535 the stack, this is uncommon, but must work correctly.
2537 Therefore, we save any area of the stack that was already
2538 written and that we are using. Here we set up to do this
2539 by making a new stack usage map from the old one. The
2540 actual save will be done by store_one_arg.
2542 Another approach might be to try to reorder the argument
2543 evaluations to avoid this conflicting stack usage. */
2545 /* Since we will be writing into the entire argument area,
2546 the map must be allocated for its entire size, not just
2547 the part that is the responsibility of the caller. */
2548 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2549 needed
+= reg_parm_stack_space
;
2551 #ifdef ARGS_GROW_DOWNWARD
2552 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2555 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2558 free (stack_usage_map_buf
);
2559 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
2560 stack_usage_map
= stack_usage_map_buf
;
2562 if (initial_highest_arg_in_use
)
2563 memcpy (stack_usage_map
, initial_stack_usage_map
,
2564 initial_highest_arg_in_use
);
2566 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2567 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2568 (highest_outgoing_arg_in_use
2569 - initial_highest_arg_in_use
));
2572 /* The address of the outgoing argument list must not be
2573 copied to a register here, because argblock would be left
2574 pointing to the wrong place after the call to
2575 allocate_dynamic_stack_space below. */
2577 argblock
= virtual_outgoing_args_rtx
;
2581 if (inhibit_defer_pop
== 0)
2583 /* Try to reuse some or all of the pending_stack_adjust
2584 to get this space. */
2586 = (combine_pending_stack_adjustment_and_call
2587 (unadjusted_args_size
,
2588 &adjusted_args_size
,
2589 preferred_unit_stack_boundary
));
2591 /* combine_pending_stack_adjustment_and_call computes
2592 an adjustment before the arguments are allocated.
2593 Account for them and see whether or not the stack
2594 needs to go up or down. */
2595 needed
= unadjusted_args_size
- needed
;
2599 /* We're releasing stack space. */
2600 /* ??? We can avoid any adjustment at all if we're
2601 already aligned. FIXME. */
2602 pending_stack_adjust
= -needed
;
2603 do_pending_stack_adjust ();
2607 /* We need to allocate space. We'll do that in
2608 push_block below. */
2609 pending_stack_adjust
= 0;
2612 /* Special case this because overhead of `push_block' in
2613 this case is non-trivial. */
2615 argblock
= virtual_outgoing_args_rtx
;
2618 argblock
= push_block (GEN_INT (needed
), 0, 0);
2619 #ifdef ARGS_GROW_DOWNWARD
2620 argblock
= plus_constant (argblock
, needed
);
2624 /* We only really need to call `copy_to_reg' in the case
2625 where push insns are going to be used to pass ARGBLOCK
2626 to a function call in ARGS. In that case, the stack
2627 pointer changes value from the allocation point to the
2628 call point, and hence the value of
2629 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2630 as well always do it. */
2631 argblock
= copy_to_reg (argblock
);
2636 if (ACCUMULATE_OUTGOING_ARGS
)
2638 /* The save/restore code in store_one_arg handles all
2639 cases except one: a constructor call (including a C
2640 function returning a BLKmode struct) to initialize
2642 if (stack_arg_under_construction
)
2645 = GEN_INT (adjusted_args_size
.constant
2646 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
2647 : TREE_TYPE (fndecl
))) ? 0
2648 : reg_parm_stack_space
));
2649 if (old_stack_level
== 0)
2651 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
2652 old_stack_pointer_delta
= stack_pointer_delta
;
2653 old_pending_adj
= pending_stack_adjust
;
2654 pending_stack_adjust
= 0;
2655 /* stack_arg_under_construction says whether a stack
2656 arg is being constructed at the old stack level.
2657 Pushing the stack gets a clean outgoing argument
2659 old_stack_arg_under_construction
2660 = stack_arg_under_construction
;
2661 stack_arg_under_construction
= 0;
2662 /* Make a new map for the new argument list. */
2663 free (stack_usage_map_buf
);
2664 stack_usage_map_buf
= XCNEWVEC (char, highest_outgoing_arg_in_use
);
2665 stack_usage_map
= stack_usage_map_buf
;
2666 highest_outgoing_arg_in_use
= 0;
2668 /* We can pass TRUE as the 4th argument because we just
2669 saved the stack pointer and will restore it right after
2671 allocate_dynamic_stack_space (push_size
, 0,
2672 BIGGEST_ALIGNMENT
, true);
2675 /* If argument evaluation might modify the stack pointer,
2676 copy the address of the argument list to a register. */
2677 for (i
= 0; i
< num_actuals
; i
++)
2678 if (args
[i
].pass_on_stack
)
2680 argblock
= copy_addr_to_reg (argblock
);
2685 compute_argument_addresses (args
, argblock
, num_actuals
);
2687 /* If we push args individually in reverse order, perform stack alignment
2688 before the first push (the last arg). */
2689 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2690 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2692 /* When the stack adjustment is pending, we get better code
2693 by combining the adjustments. */
2694 if (pending_stack_adjust
2695 && ! inhibit_defer_pop
)
2697 pending_stack_adjust
2698 = (combine_pending_stack_adjustment_and_call
2699 (unadjusted_args_size
,
2700 &adjusted_args_size
,
2701 preferred_unit_stack_boundary
));
2702 do_pending_stack_adjust ();
2704 else if (argblock
== 0)
2705 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2706 - unadjusted_args_size
));
2708 /* Now that the stack is properly aligned, pops can't safely
2709 be deferred during the evaluation of the arguments. */
2712 /* Record the maximum pushed stack space size. We need to delay
2713 doing it this far to take into account the optimization done
2714 by combine_pending_stack_adjustment_and_call. */
2715 if (flag_stack_usage
2716 && !ACCUMULATE_OUTGOING_ARGS
2718 && adjusted_args_size
.var
== 0)
2720 int pushed
= adjusted_args_size
.constant
+ pending_stack_adjust
;
2721 if (pushed
> current_function_pushed_stack_size
)
2722 current_function_pushed_stack_size
= pushed
;
2725 funexp
= rtx_for_function_call (fndecl
, addr
);
2727 /* Figure out the register where the value, if any, will come back. */
2729 if (TYPE_MODE (rettype
) != VOIDmode
2730 && ! structure_value_addr
)
2732 if (pcc_struct_value
)
2733 valreg
= hard_function_value (build_pointer_type (rettype
),
2734 fndecl
, NULL
, (pass
== 0));
2736 valreg
= hard_function_value (rettype
, fndecl
, fntype
,
2739 /* If VALREG is a PARALLEL whose first member has a zero
2740 offset, use that. This is for targets such as m68k that
2741 return the same value in multiple places. */
2742 if (GET_CODE (valreg
) == PARALLEL
)
2744 rtx elem
= XVECEXP (valreg
, 0, 0);
2745 rtx where
= XEXP (elem
, 0);
2746 rtx offset
= XEXP (elem
, 1);
2747 if (offset
== const0_rtx
2748 && GET_MODE (where
) == GET_MODE (valreg
))
2753 /* Precompute all register parameters. It isn't safe to compute anything
2754 once we have started filling any specific hard regs. */
2755 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2757 if (CALL_EXPR_STATIC_CHAIN (exp
))
2758 static_chain_value
= expand_normal (CALL_EXPR_STATIC_CHAIN (exp
));
2760 static_chain_value
= 0;
2762 #ifdef REG_PARM_STACK_SPACE
2763 /* Save the fixed argument area if it's part of the caller's frame and
2764 is clobbered by argument setup for this call. */
2765 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2766 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2767 &low_to_save
, &high_to_save
);
2770 /* Now store (and compute if necessary) all non-register parms.
2771 These come before register parms, since they can require block-moves,
2772 which could clobber the registers used for register parms.
2773 Parms which have partial registers are not stored here,
2774 but we do preallocate space here if they want that. */
2776 for (i
= 0; i
< num_actuals
; i
++)
2778 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2780 rtx before_arg
= get_last_insn ();
2782 if (store_one_arg (&args
[i
], argblock
, flags
,
2783 adjusted_args_size
.var
!= 0,
2784 reg_parm_stack_space
)
2786 && check_sibcall_argument_overlap (before_arg
,
2788 sibcall_failure
= 1;
2792 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
2793 gen_rtx_USE (VOIDmode
,
2798 /* If we have a parm that is passed in registers but not in memory
2799 and whose alignment does not permit a direct copy into registers,
2800 make a group of pseudos that correspond to each register that we
2802 if (STRICT_ALIGNMENT
)
2803 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2805 /* Now store any partially-in-registers parm.
2806 This is the last place a block-move can happen. */
2808 for (i
= 0; i
< num_actuals
; i
++)
2809 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2811 rtx before_arg
= get_last_insn ();
2813 if (store_one_arg (&args
[i
], argblock
, flags
,
2814 adjusted_args_size
.var
!= 0,
2815 reg_parm_stack_space
)
2817 && check_sibcall_argument_overlap (before_arg
,
2819 sibcall_failure
= 1;
2822 /* If we pushed args in forward order, perform stack alignment
2823 after pushing the last arg. */
2824 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
2825 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2826 - unadjusted_args_size
));
2828 /* If register arguments require space on the stack and stack space
2829 was not preallocated, allocate stack space here for arguments
2830 passed in registers. */
2831 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
2832 && !ACCUMULATE_OUTGOING_ARGS
2833 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
2834 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
2836 /* Pass the function the address in which to return a
2838 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
2840 structure_value_addr
2841 = convert_memory_address (Pmode
, structure_value_addr
);
2842 emit_move_insn (struct_value
,
2844 force_operand (structure_value_addr
,
2847 if (REG_P (struct_value
))
2848 use_reg (&call_fusage
, struct_value
);
2851 after_args
= get_last_insn ();
2852 funexp
= prepare_call_address (fndecl
, funexp
, static_chain_value
,
2853 &call_fusage
, reg_parm_seen
, pass
== 0);
2855 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
2856 pass
== 0, &sibcall_failure
);
2858 /* Save a pointer to the last insn before the call, so that we can
2859 later safely search backwards to find the CALL_INSN. */
2860 before_call
= get_last_insn ();
2862 /* Set up next argument register. For sibling calls on machines
2863 with register windows this should be the incoming register. */
2865 next_arg_reg
= targetm
.calls
.function_incoming_arg (&args_so_far
,
2870 next_arg_reg
= targetm
.calls
.function_arg (&args_so_far
,
2871 VOIDmode
, void_type_node
,
2874 /* All arguments and registers used for the call must be set up by
2877 /* Stack must be properly aligned now. */
2879 || !(stack_pointer_delta
% preferred_unit_stack_boundary
));
2881 /* Generate the actual call instruction. */
2882 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
2883 adjusted_args_size
.constant
, struct_value_size
,
2884 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
2885 flags
, & args_so_far
);
2887 /* If the call setup or the call itself overlaps with anything
2888 of the argument setup we probably clobbered our call address.
2889 In that case we can't do sibcalls. */
2891 && check_sibcall_argument_overlap (after_args
, 0, 0))
2892 sibcall_failure
= 1;
2894 /* If a non-BLKmode value is returned at the most significant end
2895 of a register, shift the register right by the appropriate amount
2896 and update VALREG accordingly. BLKmode values are handled by the
2897 group load/store machinery below. */
2898 if (!structure_value_addr
2899 && !pcc_struct_value
2900 && TYPE_MODE (rettype
) != BLKmode
2901 && targetm
.calls
.return_in_msb (rettype
))
2903 if (shift_return_value (TYPE_MODE (rettype
), false, valreg
))
2904 sibcall_failure
= 1;
2905 valreg
= gen_rtx_REG (TYPE_MODE (rettype
), REGNO (valreg
));
2908 if (pass
&& (flags
& ECF_MALLOC
))
2910 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2913 /* The return value from a malloc-like function is a pointer. */
2914 if (TREE_CODE (rettype
) == POINTER_TYPE
)
2915 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
2917 emit_move_insn (temp
, valreg
);
2919 /* The return value from a malloc-like function can not alias
2921 last
= get_last_insn ();
2922 add_reg_note (last
, REG_NOALIAS
, temp
);
2924 /* Write out the sequence. */
2925 insns
= get_insns ();
2931 /* For calls to `setjmp', etc., inform
2932 function.c:setjmp_warnings that it should complain if
2933 nonvolatile values are live. For functions that cannot
2934 return, inform flow that control does not fall through. */
2936 if ((flags
& ECF_NORETURN
) || pass
== 0)
2938 /* The barrier must be emitted
2939 immediately after the CALL_INSN. Some ports emit more
2940 than just a CALL_INSN above, so we must search for it here. */
2942 rtx last
= get_last_insn ();
2943 while (!CALL_P (last
))
2945 last
= PREV_INSN (last
);
2946 /* There was no CALL_INSN? */
2947 gcc_assert (last
!= before_call
);
2950 emit_barrier_after (last
);
2952 /* Stack adjustments after a noreturn call are dead code.
2953 However when NO_DEFER_POP is in effect, we must preserve
2954 stack_pointer_delta. */
2955 if (inhibit_defer_pop
== 0)
2957 stack_pointer_delta
= old_stack_allocated
;
2958 pending_stack_adjust
= 0;
2962 /* If value type not void, return an rtx for the value. */
2964 if (TYPE_MODE (rettype
) == VOIDmode
2966 target
= const0_rtx
;
2967 else if (structure_value_addr
)
2969 if (target
== 0 || !MEM_P (target
))
2972 = gen_rtx_MEM (TYPE_MODE (rettype
),
2973 memory_address (TYPE_MODE (rettype
),
2974 structure_value_addr
));
2975 set_mem_attributes (target
, rettype
, 1);
2978 else if (pcc_struct_value
)
2980 /* This is the special C++ case where we need to
2981 know what the true target was. We take care to
2982 never use this value more than once in one expression. */
2983 target
= gen_rtx_MEM (TYPE_MODE (rettype
),
2984 copy_to_reg (valreg
));
2985 set_mem_attributes (target
, rettype
, 1);
2987 /* Handle calls that return values in multiple non-contiguous locations.
2988 The Irix 6 ABI has examples of this. */
2989 else if (GET_CODE (valreg
) == PARALLEL
)
2993 /* This will only be assigned once, so it can be readonly. */
2994 tree nt
= build_qualified_type (rettype
,
2995 (TYPE_QUALS (rettype
)
2996 | TYPE_QUAL_CONST
));
2998 target
= assign_temp (nt
, 0, 1, 1);
3001 if (! rtx_equal_p (target
, valreg
))
3002 emit_group_store (target
, valreg
, rettype
,
3003 int_size_in_bytes (rettype
));
3005 /* We can not support sibling calls for this case. */
3006 sibcall_failure
= 1;
3009 && GET_MODE (target
) == TYPE_MODE (rettype
)
3010 && GET_MODE (target
) == GET_MODE (valreg
))
3012 bool may_overlap
= false;
3014 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
3015 reg to a plain register. */
3016 if (!REG_P (target
) || HARD_REGISTER_P (target
))
3017 valreg
= avoid_likely_spilled_reg (valreg
);
3019 /* If TARGET is a MEM in the argument area, and we have
3020 saved part of the argument area, then we can't store
3021 directly into TARGET as it may get overwritten when we
3022 restore the argument save area below. Don't work too
3023 hard though and simply force TARGET to a register if it
3024 is a MEM; the optimizer is quite likely to sort it out. */
3025 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
3026 for (i
= 0; i
< num_actuals
; i
++)
3027 if (args
[i
].save_area
)
3034 target
= copy_to_reg (valreg
);
3037 /* TARGET and VALREG cannot be equal at this point
3038 because the latter would not have
3039 REG_FUNCTION_VALUE_P true, while the former would if
3040 it were referring to the same register.
3042 If they refer to the same register, this move will be
3043 a no-op, except when function inlining is being
3045 emit_move_insn (target
, valreg
);
3047 /* If we are setting a MEM, this code must be executed.
3048 Since it is emitted after the call insn, sibcall
3049 optimization cannot be performed in that case. */
3051 sibcall_failure
= 1;
3054 else if (TYPE_MODE (rettype
) == BLKmode
)
3057 if (GET_MODE (val
) != BLKmode
)
3058 val
= avoid_likely_spilled_reg (val
);
3059 target
= copy_blkmode_from_reg (target
, val
, rettype
);
3061 /* We can not support sibling calls for this case. */
3062 sibcall_failure
= 1;
3065 target
= copy_to_reg (avoid_likely_spilled_reg (valreg
));
3067 /* If we promoted this return value, make the proper SUBREG.
3068 TARGET might be const0_rtx here, so be careful. */
3070 && TYPE_MODE (rettype
) != BLKmode
3071 && GET_MODE (target
) != TYPE_MODE (rettype
))
3073 tree type
= rettype
;
3074 int unsignedp
= TYPE_UNSIGNED (type
);
3076 enum machine_mode pmode
;
3078 /* Ensure we promote as expected, and get the new unsignedness. */
3079 pmode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
3081 gcc_assert (GET_MODE (target
) == pmode
);
3083 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
3084 && (GET_MODE_SIZE (GET_MODE (target
))
3085 > GET_MODE_SIZE (TYPE_MODE (type
))))
3087 offset
= GET_MODE_SIZE (GET_MODE (target
))
3088 - GET_MODE_SIZE (TYPE_MODE (type
));
3089 if (! BYTES_BIG_ENDIAN
)
3090 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
3091 else if (! WORDS_BIG_ENDIAN
)
3092 offset
%= UNITS_PER_WORD
;
3095 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
3096 SUBREG_PROMOTED_VAR_P (target
) = 1;
3097 SUBREG_PROMOTED_UNSIGNED_SET (target
, unsignedp
);
3100 /* If size of args is variable or this was a constructor call for a stack
3101 argument, restore saved stack-pointer value. */
3103 if (old_stack_level
)
3105 emit_stack_restore (SAVE_BLOCK
, old_stack_level
);
3106 stack_pointer_delta
= old_stack_pointer_delta
;
3107 pending_stack_adjust
= old_pending_adj
;
3108 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
3109 stack_arg_under_construction
= old_stack_arg_under_construction
;
3110 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3111 stack_usage_map
= initial_stack_usage_map
;
3112 sibcall_failure
= 1;
3114 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
3116 #ifdef REG_PARM_STACK_SPACE
3118 restore_fixed_argument_area (save_area
, argblock
,
3119 high_to_save
, low_to_save
);
3122 /* If we saved any argument areas, restore them. */
3123 for (i
= 0; i
< num_actuals
; i
++)
3124 if (args
[i
].save_area
)
3126 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
3128 = gen_rtx_MEM (save_mode
,
3129 memory_address (save_mode
,
3130 XEXP (args
[i
].stack_slot
, 0)));
3132 if (save_mode
!= BLKmode
)
3133 emit_move_insn (stack_area
, args
[i
].save_area
);
3135 emit_block_move (stack_area
, args
[i
].save_area
,
3136 GEN_INT (args
[i
].locate
.size
.constant
),
3137 BLOCK_OP_CALL_PARM
);
3140 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3141 stack_usage_map
= initial_stack_usage_map
;
3144 /* If this was alloca, record the new stack level for nonlocal gotos.
3145 Check for the handler slots since we might not have a save area
3146 for non-local gotos. */
3148 if ((flags
& ECF_MAY_BE_ALLOCA
) && cfun
->nonlocal_goto_save_area
!= 0)
3149 update_nonlocal_goto_save_area ();
3151 /* Free up storage we no longer need. */
3152 for (i
= 0; i
< num_actuals
; ++i
)
3153 free (args
[i
].aligned_regs
);
3155 insns
= get_insns ();
3160 tail_call_insns
= insns
;
3162 /* Restore the pending stack adjustment now that we have
3163 finished generating the sibling call sequence. */
3165 pending_stack_adjust
= save_pending_stack_adjust
;
3166 stack_pointer_delta
= save_stack_pointer_delta
;
3168 /* Prepare arg structure for next iteration. */
3169 for (i
= 0; i
< num_actuals
; i
++)
3172 args
[i
].aligned_regs
= 0;
3176 sbitmap_free (stored_args_map
);
3180 normal_call_insns
= insns
;
3182 /* Verify that we've deallocated all the stack we used. */
3183 gcc_assert ((flags
& ECF_NORETURN
)
3184 || (old_stack_allocated
3185 == stack_pointer_delta
- pending_stack_adjust
));
3188 /* If something prevents making this a sibling call,
3189 zero out the sequence. */
3190 if (sibcall_failure
)
3191 tail_call_insns
= NULL_RTX
;
3196 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3197 arguments too, as argument area is now clobbered by the call. */
3198 if (tail_call_insns
)
3200 emit_insn (tail_call_insns
);
3201 crtl
->tail_call_emit
= true;
3204 emit_insn (normal_call_insns
);
3206 currently_expanding_call
--;
3208 free (stack_usage_map_buf
);
3213 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3214 this function's incoming arguments.
3216 At the start of RTL generation we know the only REG_EQUIV notes
3217 in the rtl chain are those for incoming arguments, so we can look
3218 for REG_EQUIV notes between the start of the function and the
3219 NOTE_INSN_FUNCTION_BEG.
3221 This is (slight) overkill. We could keep track of the highest
3222 argument we clobber and be more selective in removing notes, but it
3223 does not seem to be worth the effort. */
3226 fixup_tail_calls (void)
3230 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
3234 /* There are never REG_EQUIV notes for the incoming arguments
3235 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3237 && NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
)
3240 note
= find_reg_note (insn
, REG_EQUIV
, 0);
3242 remove_note (insn
, note
);
3243 note
= find_reg_note (insn
, REG_EQUIV
, 0);
3248 /* Traverse a list of TYPES and expand all complex types into their
3251 split_complex_types (tree types
)
3255 /* Before allocating memory, check for the common case of no complex. */
3256 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3258 tree type
= TREE_VALUE (p
);
3259 if (TREE_CODE (type
) == COMPLEX_TYPE
3260 && targetm
.calls
.split_complex_arg (type
))
3266 types
= copy_list (types
);
3268 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3270 tree complex_type
= TREE_VALUE (p
);
3272 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
3273 && targetm
.calls
.split_complex_arg (complex_type
))
3277 /* Rewrite complex type with component type. */
3278 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
3279 next
= TREE_CHAIN (p
);
3281 /* Add another component type for the imaginary part. */
3282 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
3283 TREE_CHAIN (p
) = imag
;
3284 TREE_CHAIN (imag
) = next
;
3286 /* Skip the newly created node. */
3294 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3295 The RETVAL parameter specifies whether return value needs to be saved, other
3296 parameters are documented in the emit_library_call function below. */
3299 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
3300 enum libcall_type fn_type
,
3301 enum machine_mode outmode
, int nargs
, va_list p
)
3303 /* Total size in bytes of all the stack-parms scanned so far. */
3304 struct args_size args_size
;
3305 /* Size of arguments before any adjustments (such as rounding). */
3306 struct args_size original_args_size
;
3309 /* Todo, choose the correct decl type of orgfun. Sadly this information
3310 isn't present here, so we default to native calling abi here. */
3311 tree fndecl ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
3312 tree fntype ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
3316 CUMULATIVE_ARGS args_so_far
;
3320 enum machine_mode mode
;
3323 struct locate_and_pad_arg_data locate
;
3327 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3328 rtx call_fusage
= 0;
3331 int pcc_struct_value
= 0;
3332 int struct_value_size
= 0;
3334 int reg_parm_stack_space
= 0;
3337 tree tfom
; /* type_for_mode (outmode, 0) */
3339 #ifdef REG_PARM_STACK_SPACE
3340 /* Define the boundary of the register parm stack space that needs to be
3342 int low_to_save
= 0, high_to_save
= 0;
3343 rtx save_area
= 0; /* Place that it is saved. */
3346 /* Size of the stack reserved for parameter registers. */
3347 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3348 char *initial_stack_usage_map
= stack_usage_map
;
3349 char *stack_usage_map_buf
= NULL
;
3351 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
3353 #ifdef REG_PARM_STACK_SPACE
3354 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3357 /* By default, library functions can not throw. */
3358 flags
= ECF_NOTHROW
;
3371 flags
|= ECF_NORETURN
;
3374 flags
= ECF_NORETURN
;
3376 case LCT_RETURNS_TWICE
:
3377 flags
= ECF_RETURNS_TWICE
;
3382 /* Ensure current function's preferred stack boundary is at least
3384 if (crtl
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3385 crtl
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3387 /* If this kind of value comes back in memory,
3388 decide where in memory it should come back. */
3389 if (outmode
!= VOIDmode
)
3391 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
3392 if (aggregate_value_p (tfom
, 0))
3394 #ifdef PCC_STATIC_STRUCT_RETURN
3396 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
3397 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3398 pcc_struct_value
= 1;
3400 value
= gen_reg_rtx (outmode
);
3401 #else /* not PCC_STATIC_STRUCT_RETURN */
3402 struct_value_size
= GET_MODE_SIZE (outmode
);
3403 if (value
!= 0 && MEM_P (value
))
3406 mem_value
= assign_temp (tfom
, 0, 1, 1);
3408 /* This call returns a big structure. */
3409 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
3413 tfom
= void_type_node
;
3415 /* ??? Unfinished: must pass the memory address as an argument. */
3417 /* Copy all the libcall-arguments out of the varargs data
3418 and into a vector ARGVEC.
3420 Compute how to pass each argument. We only support a very small subset
3421 of the full argument passing conventions to limit complexity here since
3422 library functions shouldn't have many args. */
3424 argvec
= XALLOCAVEC (struct arg
, nargs
+ 1);
3425 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3427 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3428 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3430 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0, nargs
);
3433 args_size
.constant
= 0;
3440 /* If there's a structure value address to be passed,
3441 either pass it in the special place, or pass it as an extra argument. */
3442 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
3444 rtx addr
= XEXP (mem_value
, 0);
3448 /* Make sure it is a reasonable operand for a move or push insn. */
3449 if (!REG_P (addr
) && !MEM_P (addr
)
3450 && !(CONSTANT_P (addr
)
3451 && targetm
.legitimate_constant_p (Pmode
, addr
)))
3452 addr
= force_operand (addr
, NULL_RTX
);
3454 argvec
[count
].value
= addr
;
3455 argvec
[count
].mode
= Pmode
;
3456 argvec
[count
].partial
= 0;
3458 argvec
[count
].reg
= targetm
.calls
.function_arg (&args_so_far
,
3459 Pmode
, NULL_TREE
, true);
3460 gcc_assert (targetm
.calls
.arg_partial_bytes (&args_so_far
, Pmode
,
3461 NULL_TREE
, 1) == 0);
3463 locate_and_pad_parm (Pmode
, NULL_TREE
,
3464 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3467 argvec
[count
].reg
!= 0,
3469 0, NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3471 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3472 || reg_parm_stack_space
> 0)
3473 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3475 targetm
.calls
.function_arg_advance (&args_so_far
, Pmode
, (tree
) 0, true);
3480 for (; count
< nargs
; count
++)
3482 rtx val
= va_arg (p
, rtx
);
3483 enum machine_mode mode
= (enum machine_mode
) va_arg (p
, int);
3485 /* We cannot convert the arg value to the mode the library wants here;
3486 must do it earlier where we know the signedness of the arg. */
3487 gcc_assert (mode
!= BLKmode
3488 && (GET_MODE (val
) == mode
|| GET_MODE (val
) == VOIDmode
));
3490 /* Make sure it is a reasonable operand for a move or push insn. */
3491 if (!REG_P (val
) && !MEM_P (val
)
3492 && !(CONSTANT_P (val
) && targetm
.legitimate_constant_p (mode
, val
)))
3493 val
= force_operand (val
, NULL_RTX
);
3495 if (pass_by_reference (&args_so_far
, mode
, NULL_TREE
, 1))
3499 = !reference_callee_copied (&args_so_far
, mode
, NULL_TREE
, 1);
3501 /* If this was a CONST function, it is now PURE since it now
3503 if (flags
& ECF_CONST
)
3505 flags
&= ~ECF_CONST
;
3509 if (MEM_P (val
) && !must_copy
)
3513 slot
= assign_temp (lang_hooks
.types
.type_for_mode (mode
, 0),
3515 emit_move_insn (slot
, val
);
3518 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3519 gen_rtx_USE (VOIDmode
, slot
),
3522 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3523 gen_rtx_CLOBBER (VOIDmode
,
3528 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3531 argvec
[count
].value
= val
;
3532 argvec
[count
].mode
= mode
;
3534 argvec
[count
].reg
= targetm
.calls
.function_arg (&args_so_far
, mode
,
3537 argvec
[count
].partial
3538 = targetm
.calls
.arg_partial_bytes (&args_so_far
, mode
, NULL_TREE
, 1);
3540 locate_and_pad_parm (mode
, NULL_TREE
,
3541 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3544 argvec
[count
].reg
!= 0,
3546 argvec
[count
].partial
,
3547 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3549 gcc_assert (!argvec
[count
].locate
.size
.var
);
3551 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3552 || reg_parm_stack_space
> 0)
3553 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3555 targetm
.calls
.function_arg_advance (&args_so_far
, mode
, (tree
) 0, true);
3558 /* If this machine requires an external definition for library
3559 functions, write one out. */
3560 assemble_external_libcall (fun
);
3562 original_args_size
= args_size
;
3563 args_size
.constant
= (((args_size
.constant
3564 + stack_pointer_delta
3568 - stack_pointer_delta
);
3570 args_size
.constant
= MAX (args_size
.constant
,
3571 reg_parm_stack_space
);
3573 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3574 args_size
.constant
-= reg_parm_stack_space
;
3576 if (args_size
.constant
> crtl
->outgoing_args_size
)
3577 crtl
->outgoing_args_size
= args_size
.constant
;
3579 if (flag_stack_usage
&& !ACCUMULATE_OUTGOING_ARGS
)
3581 int pushed
= args_size
.constant
+ pending_stack_adjust
;
3582 if (pushed
> current_function_pushed_stack_size
)
3583 current_function_pushed_stack_size
= pushed
;
3586 if (ACCUMULATE_OUTGOING_ARGS
)
3588 /* Since the stack pointer will never be pushed, it is possible for
3589 the evaluation of a parm to clobber something we have already
3590 written to the stack. Since most function calls on RISC machines
3591 do not use the stack, this is uncommon, but must work correctly.
3593 Therefore, we save any area of the stack that was already written
3594 and that we are using. Here we set up to do this by making a new
3595 stack usage map from the old one.
3597 Another approach might be to try to reorder the argument
3598 evaluations to avoid this conflicting stack usage. */
3600 needed
= args_size
.constant
;
3602 /* Since we will be writing into the entire argument area, the
3603 map must be allocated for its entire size, not just the part that
3604 is the responsibility of the caller. */
3605 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3606 needed
+= reg_parm_stack_space
;
3608 #ifdef ARGS_GROW_DOWNWARD
3609 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3612 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3615 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
3616 stack_usage_map
= stack_usage_map_buf
;
3618 if (initial_highest_arg_in_use
)
3619 memcpy (stack_usage_map
, initial_stack_usage_map
,
3620 initial_highest_arg_in_use
);
3622 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3623 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3624 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3627 /* We must be careful to use virtual regs before they're instantiated,
3628 and real regs afterwards. Loop optimization, for example, can create
3629 new libcalls after we've instantiated the virtual regs, and if we
3630 use virtuals anyway, they won't match the rtl patterns. */
3632 if (virtuals_instantiated
)
3633 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3635 argblock
= virtual_outgoing_args_rtx
;
3640 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3643 /* If we push args individually in reverse order, perform stack alignment
3644 before the first push (the last arg). */
3645 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3646 anti_adjust_stack (GEN_INT (args_size
.constant
3647 - original_args_size
.constant
));
3649 if (PUSH_ARGS_REVERSED
)
3660 #ifdef REG_PARM_STACK_SPACE
3661 if (ACCUMULATE_OUTGOING_ARGS
)
3663 /* The argument list is the property of the called routine and it
3664 may clobber it. If the fixed area has been used for previous
3665 parameters, we must save and restore it. */
3666 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
3667 &low_to_save
, &high_to_save
);
3671 /* Push the args that need to be pushed. */
3673 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3674 are to be pushed. */
3675 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3677 enum machine_mode mode
= argvec
[argnum
].mode
;
3678 rtx val
= argvec
[argnum
].value
;
3679 rtx reg
= argvec
[argnum
].reg
;
3680 int partial
= argvec
[argnum
].partial
;
3681 unsigned int parm_align
= argvec
[argnum
].locate
.boundary
;
3682 int lower_bound
= 0, upper_bound
= 0, i
;
3684 if (! (reg
!= 0 && partial
== 0))
3688 if (ACCUMULATE_OUTGOING_ARGS
)
3690 /* If this is being stored into a pre-allocated, fixed-size,
3691 stack area, save any previous data at that location. */
3693 #ifdef ARGS_GROW_DOWNWARD
3694 /* stack_slot is negative, but we want to index stack_usage_map
3695 with positive values. */
3696 upper_bound
= -argvec
[argnum
].locate
.slot_offset
.constant
+ 1;
3697 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
3699 lower_bound
= argvec
[argnum
].locate
.slot_offset
.constant
;
3700 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
3704 /* Don't worry about things in the fixed argument area;
3705 it has already been saved. */
3706 if (i
< reg_parm_stack_space
)
3707 i
= reg_parm_stack_space
;
3708 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
3711 if (i
< upper_bound
)
3713 /* We need to make a save area. */
3715 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
3716 enum machine_mode save_mode
3717 = mode_for_size (size
, MODE_INT
, 1);
3719 = plus_constant (argblock
,
3720 argvec
[argnum
].locate
.offset
.constant
);
3722 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
3724 if (save_mode
== BLKmode
)
3726 argvec
[argnum
].save_area
3727 = assign_stack_temp (BLKmode
,
3728 argvec
[argnum
].locate
.size
.constant
,
3731 emit_block_move (validize_mem (argvec
[argnum
].save_area
),
3733 GEN_INT (argvec
[argnum
].locate
.size
.constant
),
3734 BLOCK_OP_CALL_PARM
);
3738 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3740 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3745 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, parm_align
,
3746 partial
, reg
, 0, argblock
,
3747 GEN_INT (argvec
[argnum
].locate
.offset
.constant
),
3748 reg_parm_stack_space
,
3749 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
));
3751 /* Now mark the segment we just used. */
3752 if (ACCUMULATE_OUTGOING_ARGS
)
3753 for (i
= lower_bound
; i
< upper_bound
; i
++)
3754 stack_usage_map
[i
] = 1;
3758 /* Indicate argument access so that alias.c knows that these
3761 use
= plus_constant (argblock
,
3762 argvec
[argnum
].locate
.offset
.constant
);
3764 /* When arguments are pushed, trying to tell alias.c where
3765 exactly this argument is won't work, because the
3766 auto-increment causes confusion. So we merely indicate
3767 that we access something with a known mode somewhere on
3769 use
= gen_rtx_PLUS (Pmode
, virtual_outgoing_args_rtx
,
3770 gen_rtx_SCRATCH (Pmode
));
3771 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
3772 use
= gen_rtx_USE (VOIDmode
, use
);
3773 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
3777 /* If we pushed args in forward order, perform stack alignment
3778 after pushing the last arg. */
3779 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3780 anti_adjust_stack (GEN_INT (args_size
.constant
3781 - original_args_size
.constant
));
3783 if (PUSH_ARGS_REVERSED
)
3788 fun
= prepare_call_address (NULL
, fun
, NULL
, &call_fusage
, 0, 0);
3790 /* Now load any reg parms into their regs. */
3792 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3793 are to be pushed. */
3794 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3796 enum machine_mode mode
= argvec
[argnum
].mode
;
3797 rtx val
= argvec
[argnum
].value
;
3798 rtx reg
= argvec
[argnum
].reg
;
3799 int partial
= argvec
[argnum
].partial
;
3801 /* Handle calls that pass values in multiple non-contiguous
3802 locations. The PA64 has examples of this for library calls. */
3803 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3804 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
3805 else if (reg
!= 0 && partial
== 0)
3806 emit_move_insn (reg
, val
);
3811 /* Any regs containing parms remain in use through the call. */
3812 for (count
= 0; count
< nargs
; count
++)
3814 rtx reg
= argvec
[count
].reg
;
3815 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3816 use_group_regs (&call_fusage
, reg
);
3819 int partial
= argvec
[count
].partial
;
3823 gcc_assert (partial
% UNITS_PER_WORD
== 0);
3824 nregs
= partial
/ UNITS_PER_WORD
;
3825 use_regs (&call_fusage
, REGNO (reg
), nregs
);
3828 use_reg (&call_fusage
, reg
);
3832 /* Pass the function the address in which to return a structure value. */
3833 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
3835 emit_move_insn (struct_value
,
3837 force_operand (XEXP (mem_value
, 0),
3839 if (REG_P (struct_value
))
3840 use_reg (&call_fusage
, struct_value
);
3843 /* Don't allow popping to be deferred, since then
3844 cse'ing of library calls could delete a call and leave the pop. */
3846 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
3847 ? hard_libcall_value (outmode
, orgfun
) : NULL_RTX
);
3849 /* Stack must be properly aligned now. */
3850 gcc_assert (!(stack_pointer_delta
3851 & (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1)));
3853 before_call
= get_last_insn ();
3855 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3856 will set inhibit_defer_pop to that value. */
3857 /* The return type is needed to decide how many bytes the function pops.
3858 Signedness plays no role in that, so for simplicity, we pretend it's
3859 always signed. We also assume that the list of arguments passed has
3860 no impact, so we pretend it is unknown. */
3862 emit_call_1 (fun
, NULL
,
3863 get_identifier (XSTR (orgfun
, 0)),
3864 build_function_type (tfom
, NULL_TREE
),
3865 original_args_size
.constant
, args_size
.constant
,
3867 targetm
.calls
.function_arg (&args_so_far
,
3868 VOIDmode
, void_type_node
, true),
3870 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, & args_so_far
);
3872 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
3873 that it should complain if nonvolatile values are live. For
3874 functions that cannot return, inform flow that control does not
3877 if (flags
& ECF_NORETURN
)
3879 /* The barrier note must be emitted
3880 immediately after the CALL_INSN. Some ports emit more than
3881 just a CALL_INSN above, so we must search for it here. */
3883 rtx last
= get_last_insn ();
3884 while (!CALL_P (last
))
3886 last
= PREV_INSN (last
);
3887 /* There was no CALL_INSN? */
3888 gcc_assert (last
!= before_call
);
3891 emit_barrier_after (last
);
3894 /* Now restore inhibit_defer_pop to its actual original value. */
3899 /* Copy the value to the right place. */
3900 if (outmode
!= VOIDmode
&& retval
)
3906 if (value
!= mem_value
)
3907 emit_move_insn (value
, mem_value
);
3909 else if (GET_CODE (valreg
) == PARALLEL
)
3912 value
= gen_reg_rtx (outmode
);
3913 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
3917 /* Convert to the proper mode if a promotion has been active. */
3918 if (GET_MODE (valreg
) != outmode
)
3920 int unsignedp
= TYPE_UNSIGNED (tfom
);
3922 gcc_assert (promote_function_mode (tfom
, outmode
, &unsignedp
,
3923 fndecl
? TREE_TYPE (fndecl
) : fntype
, 1)
3924 == GET_MODE (valreg
));
3925 valreg
= convert_modes (outmode
, GET_MODE (valreg
), valreg
, 0);
3929 emit_move_insn (value
, valreg
);
3935 if (ACCUMULATE_OUTGOING_ARGS
)
3937 #ifdef REG_PARM_STACK_SPACE
3939 restore_fixed_argument_area (save_area
, argblock
,
3940 high_to_save
, low_to_save
);
3943 /* If we saved any argument areas, restore them. */
3944 for (count
= 0; count
< nargs
; count
++)
3945 if (argvec
[count
].save_area
)
3947 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
3948 rtx adr
= plus_constant (argblock
,
3949 argvec
[count
].locate
.offset
.constant
);
3950 rtx stack_area
= gen_rtx_MEM (save_mode
,
3951 memory_address (save_mode
, adr
));
3953 if (save_mode
== BLKmode
)
3954 emit_block_move (stack_area
,
3955 validize_mem (argvec
[count
].save_area
),
3956 GEN_INT (argvec
[count
].locate
.size
.constant
),
3957 BLOCK_OP_CALL_PARM
);
3959 emit_move_insn (stack_area
, argvec
[count
].save_area
);
3962 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3963 stack_usage_map
= initial_stack_usage_map
;
3966 free (stack_usage_map_buf
);
3972 /* Output a library call to function FUN (a SYMBOL_REF rtx)
3973 (emitting the queue unless NO_QUEUE is nonzero),
3974 for a value of mode OUTMODE,
3975 with NARGS different arguments, passed as alternating rtx values
3976 and machine_modes to convert them to.
3978 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
3979 `const' calls, LCT_PURE for `pure' calls, or other LCT_ value for
3980 other types of library calls. */
3983 emit_library_call (rtx orgfun
, enum libcall_type fn_type
,
3984 enum machine_mode outmode
, int nargs
, ...)
3988 va_start (p
, nargs
);
3989 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
3993 /* Like emit_library_call except that an extra argument, VALUE,
3994 comes second and says where to store the result.
3995 (If VALUE is zero, this function chooses a convenient way
3996 to return the value.
3998 This function returns an rtx for where the value is to be found.
3999 If VALUE is nonzero, VALUE is returned. */
4002 emit_library_call_value (rtx orgfun
, rtx value
,
4003 enum libcall_type fn_type
,
4004 enum machine_mode outmode
, int nargs
, ...)
4009 va_start (p
, nargs
);
4010 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
4017 /* Store a single argument for a function call
4018 into the register or memory area where it must be passed.
4019 *ARG describes the argument value and where to pass it.
4021 ARGBLOCK is the address of the stack-block for all the arguments,
4022 or 0 on a machine where arguments are pushed individually.
4024 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4025 so must be careful about how the stack is used.
4027 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4028 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4029 that we need not worry about saving and restoring the stack.
4031 FNDECL is the declaration of the function we are calling.
4033 Return nonzero if this arg should cause sibcall failure,
4037 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
4038 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
4040 tree pval
= arg
->tree_value
;
4044 int i
, lower_bound
= 0, upper_bound
= 0;
4045 int sibcall_failure
= 0;
4047 if (TREE_CODE (pval
) == ERROR_MARK
)
4050 /* Push a new temporary level for any temporaries we make for
4054 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4056 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4057 save any previous data at that location. */
4058 if (argblock
&& ! variable_size
&& arg
->stack
)
4060 #ifdef ARGS_GROW_DOWNWARD
4061 /* stack_slot is negative, but we want to index stack_usage_map
4062 with positive values. */
4063 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4064 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4068 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
4070 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4071 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4075 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
4079 /* Don't worry about things in the fixed argument area;
4080 it has already been saved. */
4081 if (i
< reg_parm_stack_space
)
4082 i
= reg_parm_stack_space
;
4083 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
4086 if (i
< upper_bound
)
4088 /* We need to make a save area. */
4089 unsigned int size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
4090 enum machine_mode save_mode
= mode_for_size (size
, MODE_INT
, 1);
4091 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
4092 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
4094 if (save_mode
== BLKmode
)
4096 tree ot
= TREE_TYPE (arg
->tree_value
);
4097 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4098 | TYPE_QUAL_CONST
));
4100 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4101 preserve_temp_slots (arg
->save_area
);
4102 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4103 GEN_INT (arg
->locate
.size
.constant
),
4104 BLOCK_OP_CALL_PARM
);
4108 arg
->save_area
= gen_reg_rtx (save_mode
);
4109 emit_move_insn (arg
->save_area
, stack_area
);
4115 /* If this isn't going to be placed on both the stack and in registers,
4116 set up the register and number of words. */
4117 if (! arg
->pass_on_stack
)
4119 if (flags
& ECF_SIBCALL
)
4120 reg
= arg
->tail_call_reg
;
4123 partial
= arg
->partial
;
4126 /* Being passed entirely in a register. We shouldn't be called in
4128 gcc_assert (reg
== 0 || partial
!= 0);
4130 /* If this arg needs special alignment, don't load the registers
4132 if (arg
->n_aligned_regs
!= 0)
4135 /* If this is being passed partially in a register, we can't evaluate
4136 it directly into its stack slot. Otherwise, we can. */
4137 if (arg
->value
== 0)
4139 /* stack_arg_under_construction is nonzero if a function argument is
4140 being evaluated directly into the outgoing argument list and
4141 expand_call must take special action to preserve the argument list
4142 if it is called recursively.
4144 For scalar function arguments stack_usage_map is sufficient to
4145 determine which stack slots must be saved and restored. Scalar
4146 arguments in general have pass_on_stack == 0.
4148 If this argument is initialized by a function which takes the
4149 address of the argument (a C++ constructor or a C function
4150 returning a BLKmode structure), then stack_usage_map is
4151 insufficient and expand_call must push the stack around the
4152 function call. Such arguments have pass_on_stack == 1.
4154 Note that it is always safe to set stack_arg_under_construction,
4155 but this generates suboptimal code if set when not needed. */
4157 if (arg
->pass_on_stack
)
4158 stack_arg_under_construction
++;
4160 arg
->value
= expand_expr (pval
,
4162 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4163 ? NULL_RTX
: arg
->stack
,
4164 VOIDmode
, EXPAND_STACK_PARM
);
4166 /* If we are promoting object (or for any other reason) the mode
4167 doesn't agree, convert the mode. */
4169 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4170 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4171 arg
->value
, arg
->unsignedp
);
4173 if (arg
->pass_on_stack
)
4174 stack_arg_under_construction
--;
4177 /* Check for overlap with already clobbered argument area. */
4178 if ((flags
& ECF_SIBCALL
)
4179 && MEM_P (arg
->value
)
4180 && mem_overlaps_already_clobbered_arg_p (XEXP (arg
->value
, 0),
4181 arg
->locate
.size
.constant
))
4182 sibcall_failure
= 1;
4184 /* Don't allow anything left on stack from computation
4185 of argument to alloca. */
4186 if (flags
& ECF_MAY_BE_ALLOCA
)
4187 do_pending_stack_adjust ();
4189 if (arg
->value
== arg
->stack
)
4190 /* If the value is already in the stack slot, we are done. */
4192 else if (arg
->mode
!= BLKmode
)
4195 unsigned int parm_align
;
4197 /* Argument is a scalar, not entirely passed in registers.
4198 (If part is passed in registers, arg->partial says how much
4199 and emit_push_insn will take care of putting it there.)
4201 Push it, and if its size is less than the
4202 amount of space allocated to it,
4203 also bump stack pointer by the additional space.
4204 Note that in C the default argument promotions
4205 will prevent such mismatches. */
4207 size
= GET_MODE_SIZE (arg
->mode
);
4208 /* Compute how much space the push instruction will push.
4209 On many machines, pushing a byte will advance the stack
4210 pointer by a halfword. */
4211 #ifdef PUSH_ROUNDING
4212 size
= PUSH_ROUNDING (size
);
4216 /* Compute how much space the argument should get:
4217 round up to a multiple of the alignment for arguments. */
4218 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4219 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4220 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4221 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4223 /* Compute the alignment of the pushed argument. */
4224 parm_align
= arg
->locate
.boundary
;
4225 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4227 int pad
= used
- size
;
4230 unsigned int pad_align
= (pad
& -pad
) * BITS_PER_UNIT
;
4231 parm_align
= MIN (parm_align
, pad_align
);
4235 /* This isn't already where we want it on the stack, so put it there.
4236 This can either be done with push or copy insns. */
4237 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
,
4238 parm_align
, partial
, reg
, used
- size
, argblock
,
4239 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4240 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4242 /* Unless this is a partially-in-register argument, the argument is now
4245 arg
->value
= arg
->stack
;
4249 /* BLKmode, at least partly to be pushed. */
4251 unsigned int parm_align
;
4255 /* Pushing a nonscalar.
4256 If part is passed in registers, PARTIAL says how much
4257 and emit_push_insn will take care of putting it there. */
4259 /* Round its size up to a multiple
4260 of the allocation unit for arguments. */
4262 if (arg
->locate
.size
.var
!= 0)
4265 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
4269 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4270 for BLKmode is careful to avoid it. */
4271 excess
= (arg
->locate
.size
.constant
4272 - int_size_in_bytes (TREE_TYPE (pval
))
4274 size_rtx
= expand_expr (size_in_bytes (TREE_TYPE (pval
)),
4275 NULL_RTX
, TYPE_MODE (sizetype
),
4279 parm_align
= arg
->locate
.boundary
;
4281 /* When an argument is padded down, the block is aligned to
4282 PARM_BOUNDARY, but the actual argument isn't. */
4283 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4285 if (arg
->locate
.size
.var
)
4286 parm_align
= BITS_PER_UNIT
;
4289 unsigned int excess_align
= (excess
& -excess
) * BITS_PER_UNIT
;
4290 parm_align
= MIN (parm_align
, excess_align
);
4294 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
4296 /* emit_push_insn might not work properly if arg->value and
4297 argblock + arg->locate.offset areas overlap. */
4301 if (XEXP (x
, 0) == crtl
->args
.internal_arg_pointer
4302 || (GET_CODE (XEXP (x
, 0)) == PLUS
4303 && XEXP (XEXP (x
, 0), 0) ==
4304 crtl
->args
.internal_arg_pointer
4305 && CONST_INT_P (XEXP (XEXP (x
, 0), 1))))
4307 if (XEXP (x
, 0) != crtl
->args
.internal_arg_pointer
)
4308 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4310 /* expand_call should ensure this. */
4311 gcc_assert (!arg
->locate
.offset
.var
4312 && arg
->locate
.size
.var
== 0
4313 && CONST_INT_P (size_rtx
));
4315 if (arg
->locate
.offset
.constant
> i
)
4317 if (arg
->locate
.offset
.constant
< i
+ INTVAL (size_rtx
))
4318 sibcall_failure
= 1;
4320 else if (arg
->locate
.offset
.constant
< i
)
4322 /* Use arg->locate.size.constant instead of size_rtx
4323 because we only care about the part of the argument
4325 if (i
< (arg
->locate
.offset
.constant
4326 + arg
->locate
.size
.constant
))
4327 sibcall_failure
= 1;
4331 /* Even though they appear to be at the same location,
4332 if part of the outgoing argument is in registers,
4333 they aren't really at the same location. Check for
4334 this by making sure that the incoming size is the
4335 same as the outgoing size. */
4336 if (arg
->locate
.size
.constant
!= INTVAL (size_rtx
))
4337 sibcall_failure
= 1;
4342 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4343 parm_align
, partial
, reg
, excess
, argblock
,
4344 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4345 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4347 /* Unless this is a partially-in-register argument, the argument is now
4350 ??? Unlike the case above, in which we want the actual
4351 address of the data, so that we can load it directly into a
4352 register, here we want the address of the stack slot, so that
4353 it's properly aligned for word-by-word copying or something
4354 like that. It's not clear that this is always correct. */
4356 arg
->value
= arg
->stack_slot
;
4359 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
4361 tree type
= TREE_TYPE (arg
->tree_value
);
4363 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
4364 int_size_in_bytes (type
));
4367 /* Mark all slots this store used. */
4368 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
4369 && argblock
&& ! variable_size
&& arg
->stack
)
4370 for (i
= lower_bound
; i
< upper_bound
; i
++)
4371 stack_usage_map
[i
] = 1;
4373 /* Once we have pushed something, pops can't safely
4374 be deferred during the rest of the arguments. */
4377 /* Free any temporary slots made in processing this argument. Show
4378 that we might have taken the address of something and pushed that
4380 preserve_temp_slots (NULL_RTX
);
4384 return sibcall_failure
;
4387 /* Nonzero if we do not know how to pass TYPE solely in registers. */
4390 must_pass_in_stack_var_size (enum machine_mode mode ATTRIBUTE_UNUSED
,
4396 /* If the type has variable size... */
4397 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4400 /* If the type is marked as addressable (it is required
4401 to be constructed into the stack)... */
4402 if (TREE_ADDRESSABLE (type
))
4408 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
4409 takes trailing padding of a structure into account. */
4410 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
4413 must_pass_in_stack_var_size_or_pad (enum machine_mode mode
, const_tree type
)
4418 /* If the type has variable size... */
4419 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4422 /* If the type is marked as addressable (it is required
4423 to be constructed into the stack)... */
4424 if (TREE_ADDRESSABLE (type
))
4427 /* If the padding and mode of the type is such that a copy into
4428 a register would put it into the wrong part of the register. */
4430 && int_size_in_bytes (type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
4431 && (FUNCTION_ARG_PADDING (mode
, type
)
4432 == (BYTES_BIG_ENDIAN
? upward
: downward
)))