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_t
, 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_t 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 (*get_cumulative_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
)
277 /* Although a built-in FUNCTION_DECL and its non-__builtin
278 counterpart compare equal and get a shared mem_attrs, they
279 produce different dump output in compare-debug compilations,
280 if an entry gets garbage collected in one compilation, then
281 adds a different (but equivalent) entry, while the other
282 doesn't run the garbage collector at the same spot and then
283 shares the mem_attr with the equivalent entry. */
284 if (DECL_BUILT_IN_CLASS (t
) == BUILT_IN_NORMAL
285 && built_in_decls
[DECL_FUNCTION_CODE (t
)])
286 t
= built_in_decls
[DECL_FUNCTION_CODE (t
)];
287 set_mem_expr (funmem
, t
);
290 set_mem_expr (funmem
, build_simple_mem_ref (CALL_EXPR_FN (fntree
)));
292 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
293 if ((ecf_flags
& ECF_SIBCALL
)
294 && HAVE_sibcall_pop
&& HAVE_sibcall_value_pop
295 && (n_popped
> 0 || stack_size
== 0))
297 rtx n_pop
= GEN_INT (n_popped
);
300 /* If this subroutine pops its own args, record that in the call insn
301 if possible, for the sake of frame pointer elimination. */
304 pat
= GEN_SIBCALL_VALUE_POP (valreg
, funmem
, rounded_stack_size_rtx
,
305 next_arg_reg
, n_pop
);
307 pat
= GEN_SIBCALL_POP (funmem
, rounded_stack_size_rtx
, next_arg_reg
,
310 emit_call_insn (pat
);
316 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
317 /* If the target has "call" or "call_value" insns, then prefer them
318 if no arguments are actually popped. If the target does not have
319 "call" or "call_value" insns, then we must use the popping versions
320 even if the call has no arguments to pop. */
321 #if defined (HAVE_call) && defined (HAVE_call_value)
322 if (HAVE_call
&& HAVE_call_value
&& HAVE_call_pop
&& HAVE_call_value_pop
325 if (HAVE_call_pop
&& HAVE_call_value_pop
)
328 rtx n_pop
= GEN_INT (n_popped
);
331 /* If this subroutine pops its own args, record that in the call insn
332 if possible, for the sake of frame pointer elimination. */
335 pat
= GEN_CALL_VALUE_POP (valreg
, funmem
, rounded_stack_size_rtx
,
336 next_arg_reg
, n_pop
);
338 pat
= GEN_CALL_POP (funmem
, rounded_stack_size_rtx
, next_arg_reg
,
341 emit_call_insn (pat
);
347 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
348 if ((ecf_flags
& ECF_SIBCALL
)
349 && HAVE_sibcall
&& HAVE_sibcall_value
)
352 emit_call_insn (GEN_SIBCALL_VALUE (valreg
, funmem
,
353 rounded_stack_size_rtx
,
354 next_arg_reg
, NULL_RTX
));
356 emit_call_insn (GEN_SIBCALL (funmem
, rounded_stack_size_rtx
,
358 GEN_INT (struct_value_size
)));
363 #if defined (HAVE_call) && defined (HAVE_call_value)
364 if (HAVE_call
&& HAVE_call_value
)
367 emit_call_insn (GEN_CALL_VALUE (valreg
, funmem
, rounded_stack_size_rtx
,
368 next_arg_reg
, NULL_RTX
));
370 emit_call_insn (GEN_CALL (funmem
, rounded_stack_size_rtx
, next_arg_reg
,
371 GEN_INT (struct_value_size
)));
377 /* Find the call we just emitted. */
378 call_insn
= last_call_insn ();
380 /* Some target create a fresh MEM instead of reusing the one provided
381 above. Set its MEM_EXPR. */
382 call
= PATTERN (call_insn
);
383 if (GET_CODE (call
) == PARALLEL
)
384 call
= XVECEXP (call
, 0, 0);
385 if (GET_CODE (call
) == SET
)
386 call
= SET_SRC (call
);
387 if (GET_CODE (call
) == CALL
388 && MEM_P (XEXP (call
, 0))
389 && MEM_EXPR (XEXP (call
, 0)) == NULL_TREE
390 && MEM_EXPR (funmem
) != NULL_TREE
)
391 set_mem_expr (XEXP (call
, 0), MEM_EXPR (funmem
));
393 /* Put the register usage information there. */
394 add_function_usage_to (call_insn
, call_fusage
);
396 /* If this is a const call, then set the insn's unchanging bit. */
397 if (ecf_flags
& ECF_CONST
)
398 RTL_CONST_CALL_P (call_insn
) = 1;
400 /* If this is a pure call, then set the insn's unchanging bit. */
401 if (ecf_flags
& ECF_PURE
)
402 RTL_PURE_CALL_P (call_insn
) = 1;
404 /* If this is a const call, then set the insn's unchanging bit. */
405 if (ecf_flags
& ECF_LOOPING_CONST_OR_PURE
)
406 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn
) = 1;
408 /* Create a nothrow REG_EH_REGION note, if needed. */
409 make_reg_eh_region_note (call_insn
, ecf_flags
, 0);
411 if (ecf_flags
& ECF_NORETURN
)
412 add_reg_note (call_insn
, REG_NORETURN
, const0_rtx
);
414 if (ecf_flags
& ECF_RETURNS_TWICE
)
416 add_reg_note (call_insn
, REG_SETJMP
, const0_rtx
);
417 cfun
->calls_setjmp
= 1;
420 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
422 /* Restore this now, so that we do defer pops for this call's args
423 if the context of the call as a whole permits. */
424 inhibit_defer_pop
= old_inhibit_defer_pop
;
429 CALL_INSN_FUNCTION_USAGE (call_insn
)
430 = gen_rtx_EXPR_LIST (VOIDmode
,
431 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
432 CALL_INSN_FUNCTION_USAGE (call_insn
));
433 rounded_stack_size
-= n_popped
;
434 rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
435 stack_pointer_delta
-= n_popped
;
437 /* If popup is needed, stack realign must use DRAP */
438 if (SUPPORTS_STACK_ALIGNMENT
)
439 crtl
->need_drap
= true;
442 if (!ACCUMULATE_OUTGOING_ARGS
)
444 /* If returning from the subroutine does not automatically pop the args,
445 we need an instruction to pop them sooner or later.
446 Perhaps do it now; perhaps just record how much space to pop later.
448 If returning from the subroutine does pop the args, indicate that the
449 stack pointer will be changed. */
451 if (rounded_stack_size
!= 0)
453 if (ecf_flags
& ECF_NORETURN
)
454 /* Just pretend we did the pop. */
455 stack_pointer_delta
-= rounded_stack_size
;
456 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
457 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
458 pending_stack_adjust
+= rounded_stack_size
;
460 adjust_stack (rounded_stack_size_rtx
);
463 /* When we accumulate outgoing args, we must avoid any stack manipulations.
464 Restore the stack pointer to its original value now. Usually
465 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
466 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
467 popping variants of functions exist as well.
469 ??? We may optimize similar to defer_pop above, but it is
470 probably not worthwhile.
472 ??? It will be worthwhile to enable combine_stack_adjustments even for
475 anti_adjust_stack (GEN_INT (n_popped
));
478 /* Determine if the function identified by NAME and FNDECL is one with
479 special properties we wish to know about.
481 For example, if the function might return more than one time (setjmp), then
482 set RETURNS_TWICE to a nonzero value.
484 Similarly set NORETURN if the function is in the longjmp family.
486 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
487 space from the stack such as alloca. */
490 special_function_p (const_tree fndecl
, int flags
)
492 if (fndecl
&& DECL_NAME (fndecl
)
493 && IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) <= 17
494 /* Exclude functions not at the file scope, or not `extern',
495 since they are not the magic functions we would otherwise
497 FIXME: this should be handled with attributes, not with this
498 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
499 because you can declare fork() inside a function if you
501 && (DECL_CONTEXT (fndecl
) == NULL_TREE
502 || TREE_CODE (DECL_CONTEXT (fndecl
)) == TRANSLATION_UNIT_DECL
)
503 && TREE_PUBLIC (fndecl
))
505 const char *name
= IDENTIFIER_POINTER (DECL_NAME (fndecl
));
506 const char *tname
= name
;
508 /* We assume that alloca will always be called by name. It
509 makes no sense to pass it as a pointer-to-function to
510 anything that does not understand its behavior. */
511 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 6
513 && ! strcmp (name
, "alloca"))
514 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 16
516 && ! strcmp (name
, "__builtin_alloca"))))
517 flags
|= ECF_MAY_BE_ALLOCA
;
519 /* Disregard prefix _, __, __x or __builtin_. */
524 && !strncmp (name
+ 3, "uiltin_", 7))
526 else if (name
[1] == '_' && name
[2] == 'x')
528 else if (name
[1] == '_')
537 && (! strcmp (tname
, "setjmp")
538 || ! strcmp (tname
, "setjmp_syscall")))
540 && ! strcmp (tname
, "sigsetjmp"))
542 && ! strcmp (tname
, "savectx")))
543 flags
|= ECF_RETURNS_TWICE
;
546 && ! strcmp (tname
, "siglongjmp"))
547 flags
|= ECF_NORETURN
;
549 else if ((tname
[0] == 'q' && tname
[1] == 's'
550 && ! strcmp (tname
, "qsetjmp"))
551 || (tname
[0] == 'v' && tname
[1] == 'f'
552 && ! strcmp (tname
, "vfork"))
553 || (tname
[0] == 'g' && tname
[1] == 'e'
554 && !strcmp (tname
, "getcontext")))
555 flags
|= ECF_RETURNS_TWICE
;
557 else if (tname
[0] == 'l' && tname
[1] == 'o'
558 && ! strcmp (tname
, "longjmp"))
559 flags
|= ECF_NORETURN
;
565 /* Return nonzero when FNDECL represents a call to setjmp. */
568 setjmp_call_p (const_tree fndecl
)
570 if (DECL_IS_RETURNS_TWICE (fndecl
))
571 return ECF_RETURNS_TWICE
;
572 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
576 /* Return true if STMT is an alloca call. */
579 gimple_alloca_call_p (const_gimple stmt
)
583 if (!is_gimple_call (stmt
))
586 fndecl
= gimple_call_fndecl (stmt
);
587 if (fndecl
&& (special_function_p (fndecl
, 0) & ECF_MAY_BE_ALLOCA
))
593 /* Return true when exp contains alloca call. */
596 alloca_call_p (const_tree exp
)
598 if (TREE_CODE (exp
) == CALL_EXPR
599 && TREE_CODE (CALL_EXPR_FN (exp
)) == ADDR_EXPR
600 && (TREE_CODE (TREE_OPERAND (CALL_EXPR_FN (exp
), 0)) == FUNCTION_DECL
)
601 && (special_function_p (TREE_OPERAND (CALL_EXPR_FN (exp
), 0), 0)
602 & ECF_MAY_BE_ALLOCA
))
607 /* Detect flags (function attributes) from the function decl or type node. */
610 flags_from_decl_or_type (const_tree exp
)
616 /* The function exp may have the `malloc' attribute. */
617 if (DECL_IS_MALLOC (exp
))
620 /* The function exp may have the `returns_twice' attribute. */
621 if (DECL_IS_RETURNS_TWICE (exp
))
622 flags
|= ECF_RETURNS_TWICE
;
624 /* Process the pure and const attributes. */
625 if (TREE_READONLY (exp
))
627 if (DECL_PURE_P (exp
))
629 if (DECL_LOOPING_CONST_OR_PURE_P (exp
))
630 flags
|= ECF_LOOPING_CONST_OR_PURE
;
632 if (DECL_IS_NOVOPS (exp
))
634 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp
)))
637 if (TREE_NOTHROW (exp
))
638 flags
|= ECF_NOTHROW
;
640 flags
= special_function_p (exp
, flags
);
642 else if (TYPE_P (exp
) && TYPE_READONLY (exp
))
645 if (TREE_THIS_VOLATILE (exp
))
647 flags
|= ECF_NORETURN
;
648 if (flags
& (ECF_CONST
|ECF_PURE
))
649 flags
|= ECF_LOOPING_CONST_OR_PURE
;
655 /* Detect flags from a CALL_EXPR. */
658 call_expr_flags (const_tree t
)
661 tree decl
= get_callee_fndecl (t
);
664 flags
= flags_from_decl_or_type (decl
);
667 t
= TREE_TYPE (CALL_EXPR_FN (t
));
668 if (t
&& TREE_CODE (t
) == POINTER_TYPE
)
669 flags
= flags_from_decl_or_type (TREE_TYPE (t
));
677 /* Precompute all register parameters as described by ARGS, storing values
678 into fields within the ARGS array.
680 NUM_ACTUALS indicates the total number elements in the ARGS array.
682 Set REG_PARM_SEEN if we encounter a register parameter. */
685 precompute_register_parameters (int num_actuals
, struct arg_data
*args
,
692 for (i
= 0; i
< num_actuals
; i
++)
693 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
697 if (args
[i
].value
== 0)
700 args
[i
].value
= expand_normal (args
[i
].tree_value
);
701 preserve_temp_slots (args
[i
].value
);
705 /* If the value is a non-legitimate constant, force it into a
706 pseudo now. TLS symbols sometimes need a call to resolve. */
707 if (CONSTANT_P (args
[i
].value
)
708 && !targetm
.legitimate_constant_p (args
[i
].mode
, args
[i
].value
))
709 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
711 /* If we are to promote the function arg to a wider mode,
714 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
716 = convert_modes (args
[i
].mode
,
717 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
718 args
[i
].value
, args
[i
].unsignedp
);
720 /* If we're going to have to load the value by parts, pull the
721 parts into pseudos. The part extraction process can involve
722 non-trivial computation. */
723 if (GET_CODE (args
[i
].reg
) == PARALLEL
)
725 tree type
= TREE_TYPE (args
[i
].tree_value
);
726 args
[i
].parallel_value
727 = emit_group_load_into_temps (args
[i
].reg
, args
[i
].value
,
728 type
, int_size_in_bytes (type
));
731 /* If the value is expensive, and we are inside an appropriately
732 short loop, put the value into a pseudo and then put the pseudo
735 For small register classes, also do this if this call uses
736 register parameters. This is to avoid reload conflicts while
737 loading the parameters registers. */
739 else if ((! (REG_P (args
[i
].value
)
740 || (GET_CODE (args
[i
].value
) == SUBREG
741 && REG_P (SUBREG_REG (args
[i
].value
)))))
742 && args
[i
].mode
!= BLKmode
743 && rtx_cost (args
[i
].value
, SET
, optimize_insn_for_speed_p ())
746 && targetm
.small_register_classes_for_mode_p (args
[i
].mode
))
748 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
752 #ifdef REG_PARM_STACK_SPACE
754 /* The argument list is the property of the called routine and it
755 may clobber it. If the fixed area has been used for previous
756 parameters, we must save and restore it. */
759 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
764 /* Compute the boundary of the area that needs to be saved, if any. */
765 high
= reg_parm_stack_space
;
766 #ifdef ARGS_GROW_DOWNWARD
769 if (high
> highest_outgoing_arg_in_use
)
770 high
= highest_outgoing_arg_in_use
;
772 for (low
= 0; low
< high
; low
++)
773 if (stack_usage_map
[low
] != 0)
776 enum machine_mode save_mode
;
781 while (stack_usage_map
[--high
] == 0)
785 *high_to_save
= high
;
787 num_to_save
= high
- low
+ 1;
788 save_mode
= mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
790 /* If we don't have the required alignment, must do this
792 if ((low
& (MIN (GET_MODE_SIZE (save_mode
),
793 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
796 #ifdef ARGS_GROW_DOWNWARD
801 stack_area
= gen_rtx_MEM (save_mode
,
802 memory_address (save_mode
,
803 plus_constant (argblock
,
806 set_mem_align (stack_area
, PARM_BOUNDARY
);
807 if (save_mode
== BLKmode
)
809 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
810 emit_block_move (validize_mem (save_area
), stack_area
,
811 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
815 save_area
= gen_reg_rtx (save_mode
);
816 emit_move_insn (save_area
, stack_area
);
826 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
828 enum machine_mode save_mode
= GET_MODE (save_area
);
832 #ifdef ARGS_GROW_DOWNWARD
833 delta
= -high_to_save
;
837 stack_area
= gen_rtx_MEM (save_mode
,
838 memory_address (save_mode
,
839 plus_constant (argblock
, delta
)));
840 set_mem_align (stack_area
, PARM_BOUNDARY
);
842 if (save_mode
!= BLKmode
)
843 emit_move_insn (stack_area
, save_area
);
845 emit_block_move (stack_area
, validize_mem (save_area
),
846 GEN_INT (high_to_save
- low_to_save
+ 1),
849 #endif /* REG_PARM_STACK_SPACE */
851 /* If any elements in ARGS refer to parameters that are to be passed in
852 registers, but not in memory, and whose alignment does not permit a
853 direct copy into registers. Copy the values into a group of pseudos
854 which we will later copy into the appropriate hard registers.
856 Pseudos for each unaligned argument will be stored into the array
857 args[argnum].aligned_regs. The caller is responsible for deallocating
858 the aligned_regs array if it is nonzero. */
861 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
865 for (i
= 0; i
< num_actuals
; i
++)
866 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
867 && args
[i
].mode
== BLKmode
868 && MEM_P (args
[i
].value
)
869 && (MEM_ALIGN (args
[i
].value
)
870 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
872 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
873 int endian_correction
= 0;
877 gcc_assert (args
[i
].partial
% UNITS_PER_WORD
== 0);
878 args
[i
].n_aligned_regs
= args
[i
].partial
/ UNITS_PER_WORD
;
882 args
[i
].n_aligned_regs
883 = (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
886 args
[i
].aligned_regs
= XNEWVEC (rtx
, args
[i
].n_aligned_regs
);
888 /* Structures smaller than a word are normally aligned to the
889 least significant byte. On a BYTES_BIG_ENDIAN machine,
890 this means we must skip the empty high order bytes when
891 calculating the bit offset. */
892 if (bytes
< UNITS_PER_WORD
893 #ifdef BLOCK_REG_PADDING
894 && (BLOCK_REG_PADDING (args
[i
].mode
,
895 TREE_TYPE (args
[i
].tree_value
), 1)
901 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
903 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
905 rtx reg
= gen_reg_rtx (word_mode
);
906 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
907 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
909 args
[i
].aligned_regs
[j
] = reg
;
910 word
= extract_bit_field (word
, bitsize
, 0, 1, false, NULL_RTX
,
911 word_mode
, word_mode
);
913 /* There is no need to restrict this code to loading items
914 in TYPE_ALIGN sized hunks. The bitfield instructions can
915 load up entire word sized registers efficiently.
917 ??? This may not be needed anymore.
918 We use to emit a clobber here but that doesn't let later
919 passes optimize the instructions we emit. By storing 0 into
920 the register later passes know the first AND to zero out the
921 bitfield being set in the register is unnecessary. The store
922 of 0 will be deleted as will at least the first AND. */
924 emit_move_insn (reg
, const0_rtx
);
926 bytes
-= bitsize
/ BITS_PER_UNIT
;
927 store_bit_field (reg
, bitsize
, endian_correction
, word_mode
,
933 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
936 NUM_ACTUALS is the total number of parameters.
938 N_NAMED_ARGS is the total number of named arguments.
940 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
943 FNDECL is the tree code for the target of this call (if known)
945 ARGS_SO_FAR holds state needed by the target to know where to place
948 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
949 for arguments which are passed in registers.
951 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
952 and may be modified by this routine.
954 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
955 flags which may may be modified by this routine.
957 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
958 that requires allocation of stack space.
960 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
961 the thunked-to function. */
964 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
965 struct arg_data
*args
,
966 struct args_size
*args_size
,
967 int n_named_args ATTRIBUTE_UNUSED
,
968 tree exp
, tree struct_value_addr_value
,
969 tree fndecl
, tree fntype
,
970 cumulative_args_t args_so_far
,
971 int reg_parm_stack_space
,
972 rtx
*old_stack_level
, int *old_pending_adj
,
973 int *must_preallocate
, int *ecf_flags
,
974 bool *may_tailcall
, bool call_from_thunk_p
)
976 CUMULATIVE_ARGS
*args_so_far_pnt
= get_cumulative_args (args_so_far
);
977 location_t loc
= EXPR_LOCATION (exp
);
978 /* 1 if scanning parms front to back, -1 if scanning back to front. */
981 /* Count arg position in order args appear. */
986 args_size
->constant
= 0;
989 /* In this loop, we consider args in the order they are written.
990 We fill up ARGS from the front or from the back if necessary
991 so that in any case the first arg to be pushed ends up at the front. */
993 if (PUSH_ARGS_REVERSED
)
995 i
= num_actuals
- 1, inc
= -1;
996 /* In this case, must reverse order of args
997 so that we compute and push the last arg first. */
1004 /* First fill in the actual arguments in the ARGS array, splitting
1005 complex arguments if necessary. */
1008 call_expr_arg_iterator iter
;
1011 if (struct_value_addr_value
)
1013 args
[j
].tree_value
= struct_value_addr_value
;
1016 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
1018 tree argtype
= TREE_TYPE (arg
);
1019 if (targetm
.calls
.split_complex_arg
1021 && TREE_CODE (argtype
) == COMPLEX_TYPE
1022 && targetm
.calls
.split_complex_arg (argtype
))
1024 tree subtype
= TREE_TYPE (argtype
);
1025 args
[j
].tree_value
= build1 (REALPART_EXPR
, subtype
, arg
);
1027 args
[j
].tree_value
= build1 (IMAGPART_EXPR
, subtype
, arg
);
1030 args
[j
].tree_value
= arg
;
1035 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1036 for (argpos
= 0; argpos
< num_actuals
; i
+= inc
, argpos
++)
1038 tree type
= TREE_TYPE (args
[i
].tree_value
);
1040 enum machine_mode mode
;
1042 /* Replace erroneous argument with constant zero. */
1043 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1044 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1046 /* If TYPE is a transparent union or record, pass things the way
1047 we would pass the first field of the union or record. We have
1048 already verified that the modes are the same. */
1049 if ((TREE_CODE (type
) == UNION_TYPE
|| TREE_CODE (type
) == RECORD_TYPE
)
1050 && TYPE_TRANSPARENT_AGGR (type
))
1051 type
= TREE_TYPE (first_field (type
));
1053 /* Decide where to pass this arg.
1055 args[i].reg is nonzero if all or part is passed in registers.
1057 args[i].partial is nonzero if part but not all is passed in registers,
1058 and the exact value says how many bytes are passed in registers.
1060 args[i].pass_on_stack is nonzero if the argument must at least be
1061 computed on the stack. It may then be loaded back into registers
1062 if args[i].reg is nonzero.
1064 These decisions are driven by the FUNCTION_... macros and must agree
1065 with those made by function.c. */
1067 /* See if this argument should be passed by invisible reference. */
1068 if (pass_by_reference (args_so_far_pnt
, TYPE_MODE (type
),
1069 type
, argpos
< n_named_args
))
1075 = reference_callee_copied (args_so_far_pnt
, TYPE_MODE (type
),
1076 type
, argpos
< n_named_args
);
1078 /* If we're compiling a thunk, pass through invisible references
1079 instead of making a copy. */
1080 if (call_from_thunk_p
1082 && !TREE_ADDRESSABLE (type
)
1083 && (base
= get_base_address (args
[i
].tree_value
))
1084 && TREE_CODE (base
) != SSA_NAME
1085 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
)))))
1087 /* We can't use sibcalls if a callee-copied argument is
1088 stored in the current function's frame. */
1089 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
1090 *may_tailcall
= false;
1092 args
[i
].tree_value
= build_fold_addr_expr_loc (loc
,
1093 args
[i
].tree_value
);
1094 type
= TREE_TYPE (args
[i
].tree_value
);
1096 if (*ecf_flags
& ECF_CONST
)
1097 *ecf_flags
&= ~(ECF_CONST
| ECF_LOOPING_CONST_OR_PURE
);
1101 /* We make a copy of the object and pass the address to the
1102 function being called. */
1105 if (!COMPLETE_TYPE_P (type
)
1106 || TREE_CODE (TYPE_SIZE_UNIT (type
)) != INTEGER_CST
1107 || (flag_stack_check
== GENERIC_STACK_CHECK
1108 && compare_tree_int (TYPE_SIZE_UNIT (type
),
1109 STACK_CHECK_MAX_VAR_SIZE
) > 0))
1111 /* This is a variable-sized object. Make space on the stack
1113 rtx size_rtx
= expr_size (args
[i
].tree_value
);
1115 if (*old_stack_level
== 0)
1117 emit_stack_save (SAVE_BLOCK
, old_stack_level
);
1118 *old_pending_adj
= pending_stack_adjust
;
1119 pending_stack_adjust
= 0;
1122 /* We can pass TRUE as the 4th argument because we just
1123 saved the stack pointer and will restore it right after
1125 copy
= allocate_dynamic_stack_space (size_rtx
,
1129 copy
= gen_rtx_MEM (BLKmode
, copy
);
1130 set_mem_attributes (copy
, type
, 1);
1133 copy
= assign_temp (type
, 0, 1, 0);
1135 store_expr (args
[i
].tree_value
, copy
, 0, false);
1137 /* Just change the const function to pure and then let
1138 the next test clear the pure based on
1140 if (*ecf_flags
& ECF_CONST
)
1142 *ecf_flags
&= ~ECF_CONST
;
1143 *ecf_flags
|= ECF_PURE
;
1146 if (!callee_copies
&& *ecf_flags
& ECF_PURE
)
1147 *ecf_flags
&= ~(ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
1150 = build_fold_addr_expr_loc (loc
, make_tree (type
, copy
));
1151 type
= TREE_TYPE (args
[i
].tree_value
);
1152 *may_tailcall
= false;
1156 unsignedp
= TYPE_UNSIGNED (type
);
1157 mode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
1158 fndecl
? TREE_TYPE (fndecl
) : fntype
, 0);
1160 args
[i
].unsignedp
= unsignedp
;
1161 args
[i
].mode
= mode
;
1163 args
[i
].reg
= targetm
.calls
.function_arg (args_so_far
, mode
, type
,
1164 argpos
< n_named_args
);
1166 /* If this is a sibling call and the machine has register windows, the
1167 register window has to be unwinded before calling the routine, so
1168 arguments have to go into the incoming registers. */
1169 if (targetm
.calls
.function_incoming_arg
!= targetm
.calls
.function_arg
)
1170 args
[i
].tail_call_reg
1171 = targetm
.calls
.function_incoming_arg (args_so_far
, mode
, type
,
1172 argpos
< n_named_args
);
1174 args
[i
].tail_call_reg
= args
[i
].reg
;
1178 = targetm
.calls
.arg_partial_bytes (args_so_far
, mode
, type
,
1179 argpos
< n_named_args
);
1181 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (mode
, type
);
1183 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1184 it means that we are to pass this arg in the register(s) designated
1185 by the PARALLEL, but also to pass it in the stack. */
1186 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1187 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1188 args
[i
].pass_on_stack
= 1;
1190 /* If this is an addressable type, we must preallocate the stack
1191 since we must evaluate the object into its final location.
1193 If this is to be passed in both registers and the stack, it is simpler
1195 if (TREE_ADDRESSABLE (type
)
1196 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1197 *must_preallocate
= 1;
1199 /* Compute the stack-size of this argument. */
1200 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1201 || reg_parm_stack_space
> 0
1202 || args
[i
].pass_on_stack
)
1203 locate_and_pad_parm (mode
, type
,
1204 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1209 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
1210 fndecl
, args_size
, &args
[i
].locate
);
1211 #ifdef BLOCK_REG_PADDING
1213 /* The argument is passed entirely in registers. See at which
1214 end it should be padded. */
1215 args
[i
].locate
.where_pad
=
1216 BLOCK_REG_PADDING (mode
, type
,
1217 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
1220 /* Update ARGS_SIZE, the total stack space for args so far. */
1222 args_size
->constant
+= args
[i
].locate
.size
.constant
;
1223 if (args
[i
].locate
.size
.var
)
1224 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
1226 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1227 have been used, etc. */
1229 targetm
.calls
.function_arg_advance (args_so_far
, TYPE_MODE (type
),
1230 type
, argpos
< n_named_args
);
1234 /* Update ARGS_SIZE to contain the total size for the argument block.
1235 Return the original constant component of the argument block's size.
1237 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1238 for arguments passed in registers. */
1241 compute_argument_block_size (int reg_parm_stack_space
,
1242 struct args_size
*args_size
,
1243 tree fndecl ATTRIBUTE_UNUSED
,
1244 tree fntype ATTRIBUTE_UNUSED
,
1245 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
1247 int unadjusted_args_size
= args_size
->constant
;
1249 /* For accumulate outgoing args mode we don't need to align, since the frame
1250 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1251 backends from generating misaligned frame sizes. */
1252 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1253 preferred_stack_boundary
= STACK_BOUNDARY
;
1255 /* Compute the actual size of the argument block required. The variable
1256 and constant sizes must be combined, the size may have to be rounded,
1257 and there may be a minimum required size. */
1261 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1262 args_size
->constant
= 0;
1264 preferred_stack_boundary
/= BITS_PER_UNIT
;
1265 if (preferred_stack_boundary
> 1)
1267 /* We don't handle this case yet. To handle it correctly we have
1268 to add the delta, round and subtract the delta.
1269 Currently no machine description requires this support. */
1270 gcc_assert (!(stack_pointer_delta
& (preferred_stack_boundary
- 1)));
1271 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1274 if (reg_parm_stack_space
> 0)
1277 = size_binop (MAX_EXPR
, args_size
->var
,
1278 ssize_int (reg_parm_stack_space
));
1280 /* The area corresponding to register parameters is not to count in
1281 the size of the block we need. So make the adjustment. */
1282 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
1284 = size_binop (MINUS_EXPR
, args_size
->var
,
1285 ssize_int (reg_parm_stack_space
));
1290 preferred_stack_boundary
/= BITS_PER_UNIT
;
1291 if (preferred_stack_boundary
< 1)
1292 preferred_stack_boundary
= 1;
1293 args_size
->constant
= (((args_size
->constant
1294 + stack_pointer_delta
1295 + preferred_stack_boundary
- 1)
1296 / preferred_stack_boundary
1297 * preferred_stack_boundary
)
1298 - stack_pointer_delta
);
1300 args_size
->constant
= MAX (args_size
->constant
,
1301 reg_parm_stack_space
);
1303 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
1304 args_size
->constant
-= reg_parm_stack_space
;
1306 return unadjusted_args_size
;
1309 /* Precompute parameters as needed for a function call.
1311 FLAGS is mask of ECF_* constants.
1313 NUM_ACTUALS is the number of arguments.
1315 ARGS is an array containing information for each argument; this
1316 routine fills in the INITIAL_VALUE and VALUE fields for each
1317 precomputed argument. */
1320 precompute_arguments (int num_actuals
, struct arg_data
*args
)
1324 /* If this is a libcall, then precompute all arguments so that we do not
1325 get extraneous instructions emitted as part of the libcall sequence. */
1327 /* If we preallocated the stack space, and some arguments must be passed
1328 on the stack, then we must precompute any parameter which contains a
1329 function call which will store arguments on the stack.
1330 Otherwise, evaluating the parameter may clobber previous parameters
1331 which have already been stored into the stack. (we have code to avoid
1332 such case by saving the outgoing stack arguments, but it results in
1334 if (!ACCUMULATE_OUTGOING_ARGS
)
1337 for (i
= 0; i
< num_actuals
; i
++)
1340 enum machine_mode mode
;
1342 if (TREE_CODE (args
[i
].tree_value
) != CALL_EXPR
)
1345 /* If this is an addressable type, we cannot pre-evaluate it. */
1346 type
= TREE_TYPE (args
[i
].tree_value
);
1347 gcc_assert (!TREE_ADDRESSABLE (type
));
1349 args
[i
].initial_value
= args
[i
].value
1350 = expand_normal (args
[i
].tree_value
);
1352 mode
= TYPE_MODE (type
);
1353 if (mode
!= args
[i
].mode
)
1355 int unsignedp
= args
[i
].unsignedp
;
1357 = convert_modes (args
[i
].mode
, mode
,
1358 args
[i
].value
, args
[i
].unsignedp
);
1360 /* CSE will replace this only if it contains args[i].value
1361 pseudo, so convert it down to the declared mode using
1363 if (REG_P (args
[i
].value
)
1364 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
1365 && promote_mode (type
, mode
, &unsignedp
) != args
[i
].mode
)
1367 args
[i
].initial_value
1368 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1369 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1370 SUBREG_PROMOTED_UNSIGNED_SET (args
[i
].initial_value
,
1377 /* Given the current state of MUST_PREALLOCATE and information about
1378 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1379 compute and return the final value for MUST_PREALLOCATE. */
1382 finalize_must_preallocate (int must_preallocate
, int num_actuals
,
1383 struct arg_data
*args
, struct args_size
*args_size
)
1385 /* See if we have or want to preallocate stack space.
1387 If we would have to push a partially-in-regs parm
1388 before other stack parms, preallocate stack space instead.
1390 If the size of some parm is not a multiple of the required stack
1391 alignment, we must preallocate.
1393 If the total size of arguments that would otherwise create a copy in
1394 a temporary (such as a CALL) is more than half the total argument list
1395 size, preallocation is faster.
1397 Another reason to preallocate is if we have a machine (like the m88k)
1398 where stack alignment is required to be maintained between every
1399 pair of insns, not just when the call is made. However, we assume here
1400 that such machines either do not have push insns (and hence preallocation
1401 would occur anyway) or the problem is taken care of with
1404 if (! must_preallocate
)
1406 int partial_seen
= 0;
1407 int copy_to_evaluate_size
= 0;
1410 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1412 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1414 else if (partial_seen
&& args
[i
].reg
== 0)
1415 must_preallocate
= 1;
1417 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1418 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1419 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1420 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1421 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1422 copy_to_evaluate_size
1423 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1426 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1427 && args_size
->constant
> 0)
1428 must_preallocate
= 1;
1430 return must_preallocate
;
1433 /* If we preallocated stack space, compute the address of each argument
1434 and store it into the ARGS array.
1436 We need not ensure it is a valid memory address here; it will be
1437 validized when it is used.
1439 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1442 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
1446 rtx arg_reg
= argblock
;
1447 int i
, arg_offset
= 0;
1449 if (GET_CODE (argblock
) == PLUS
)
1450 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1452 for (i
= 0; i
< num_actuals
; i
++)
1454 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
1455 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
1457 unsigned int align
, boundary
;
1458 unsigned int units_on_stack
= 0;
1459 enum machine_mode partial_mode
= VOIDmode
;
1461 /* Skip this parm if it will not be passed on the stack. */
1462 if (! args
[i
].pass_on_stack
1464 && args
[i
].partial
== 0)
1467 if (CONST_INT_P (offset
))
1468 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1470 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1472 addr
= plus_constant (addr
, arg_offset
);
1474 if (args
[i
].partial
!= 0)
1476 /* Only part of the parameter is being passed on the stack.
1477 Generate a simple memory reference of the correct size. */
1478 units_on_stack
= args
[i
].locate
.size
.constant
;
1479 partial_mode
= mode_for_size (units_on_stack
* BITS_PER_UNIT
,
1481 args
[i
].stack
= gen_rtx_MEM (partial_mode
, addr
);
1482 set_mem_size (args
[i
].stack
, GEN_INT (units_on_stack
));
1486 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1487 set_mem_attributes (args
[i
].stack
,
1488 TREE_TYPE (args
[i
].tree_value
), 1);
1490 align
= BITS_PER_UNIT
;
1491 boundary
= args
[i
].locate
.boundary
;
1492 if (args
[i
].locate
.where_pad
!= downward
)
1494 else if (CONST_INT_P (offset
))
1496 align
= INTVAL (offset
) * BITS_PER_UNIT
| boundary
;
1497 align
= align
& -align
;
1499 set_mem_align (args
[i
].stack
, align
);
1501 if (CONST_INT_P (slot_offset
))
1502 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1504 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1506 addr
= plus_constant (addr
, arg_offset
);
1508 if (args
[i
].partial
!= 0)
1510 /* Only part of the parameter is being passed on the stack.
1511 Generate a simple memory reference of the correct size.
1513 args
[i
].stack_slot
= gen_rtx_MEM (partial_mode
, addr
);
1514 set_mem_size (args
[i
].stack_slot
, GEN_INT (units_on_stack
));
1518 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1519 set_mem_attributes (args
[i
].stack_slot
,
1520 TREE_TYPE (args
[i
].tree_value
), 1);
1522 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
1524 /* Function incoming arguments may overlap with sibling call
1525 outgoing arguments and we cannot allow reordering of reads
1526 from function arguments with stores to outgoing arguments
1527 of sibling calls. */
1528 set_mem_alias_set (args
[i
].stack
, 0);
1529 set_mem_alias_set (args
[i
].stack_slot
, 0);
1534 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1535 in a call instruction.
1537 FNDECL is the tree node for the target function. For an indirect call
1538 FNDECL will be NULL_TREE.
1540 ADDR is the operand 0 of CALL_EXPR for this call. */
1543 rtx_for_function_call (tree fndecl
, tree addr
)
1547 /* Get the function to call, in the form of RTL. */
1550 /* If this is the first use of the function, see if we need to
1551 make an external definition for it. */
1552 if (!TREE_USED (fndecl
) && fndecl
!= current_function_decl
)
1554 assemble_external (fndecl
);
1555 TREE_USED (fndecl
) = 1;
1558 /* Get a SYMBOL_REF rtx for the function address. */
1559 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1562 /* Generate an rtx (probably a pseudo-register) for the address. */
1565 funexp
= expand_normal (addr
);
1566 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1571 /* Return true if and only if SIZE storage units (usually bytes)
1572 starting from address ADDR overlap with already clobbered argument
1573 area. This function is used to determine if we should give up a
1577 mem_overlaps_already_clobbered_arg_p (rtx addr
, unsigned HOST_WIDE_INT size
)
1581 if (addr
== crtl
->args
.internal_arg_pointer
)
1583 else if (GET_CODE (addr
) == PLUS
1584 && XEXP (addr
, 0) == crtl
->args
.internal_arg_pointer
1585 && CONST_INT_P (XEXP (addr
, 1)))
1586 i
= INTVAL (XEXP (addr
, 1));
1587 /* Return true for arg pointer based indexed addressing. */
1588 else if (GET_CODE (addr
) == PLUS
1589 && (XEXP (addr
, 0) == crtl
->args
.internal_arg_pointer
1590 || XEXP (addr
, 1) == crtl
->args
.internal_arg_pointer
))
1595 #ifdef ARGS_GROW_DOWNWARD
1600 unsigned HOST_WIDE_INT k
;
1602 for (k
= 0; k
< size
; k
++)
1603 if (i
+ k
< stored_args_map
->n_bits
1604 && TEST_BIT (stored_args_map
, i
+ k
))
1611 /* Do the register loads required for any wholly-register parms or any
1612 parms which are passed both on the stack and in a register. Their
1613 expressions were already evaluated.
1615 Mark all register-parms as living through the call, putting these USE
1616 insns in the CALL_INSN_FUNCTION_USAGE field.
1618 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1619 checking, setting *SIBCALL_FAILURE if appropriate. */
1622 load_register_parameters (struct arg_data
*args
, int num_actuals
,
1623 rtx
*call_fusage
, int flags
, int is_sibcall
,
1624 int *sibcall_failure
)
1628 for (i
= 0; i
< num_actuals
; i
++)
1630 rtx reg
= ((flags
& ECF_SIBCALL
)
1631 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1634 int partial
= args
[i
].partial
;
1637 rtx before_arg
= get_last_insn ();
1638 /* Set non-negative if we must move a word at a time, even if
1639 just one word (e.g, partial == 4 && mode == DFmode). Set
1640 to -1 if we just use a normal move insn. This value can be
1641 zero if the argument is a zero size structure. */
1643 if (GET_CODE (reg
) == PARALLEL
)
1647 gcc_assert (partial
% UNITS_PER_WORD
== 0);
1648 nregs
= partial
/ UNITS_PER_WORD
;
1650 else if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
)
1652 size
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1653 nregs
= (size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1656 size
= GET_MODE_SIZE (args
[i
].mode
);
1658 /* Handle calls that pass values in multiple non-contiguous
1659 locations. The Irix 6 ABI has examples of this. */
1661 if (GET_CODE (reg
) == PARALLEL
)
1662 emit_group_move (reg
, args
[i
].parallel_value
);
1664 /* If simple case, just do move. If normal partial, store_one_arg
1665 has already loaded the register for us. In all other cases,
1666 load the register(s) from memory. */
1668 else if (nregs
== -1)
1670 emit_move_insn (reg
, args
[i
].value
);
1671 #ifdef BLOCK_REG_PADDING
1672 /* Handle case where we have a value that needs shifting
1673 up to the msb. eg. a QImode value and we're padding
1674 upward on a BYTES_BIG_ENDIAN machine. */
1675 if (size
< UNITS_PER_WORD
1676 && (args
[i
].locate
.where_pad
1677 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
1680 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1682 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1683 report the whole reg as used. Strictly speaking, the
1684 call only uses SIZE bytes at the msb end, but it doesn't
1685 seem worth generating rtl to say that. */
1686 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
1687 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
, shift
, reg
, 1);
1689 emit_move_insn (reg
, x
);
1694 /* If we have pre-computed the values to put in the registers in
1695 the case of non-aligned structures, copy them in now. */
1697 else if (args
[i
].n_aligned_regs
!= 0)
1698 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1699 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1700 args
[i
].aligned_regs
[j
]);
1702 else if (partial
== 0 || args
[i
].pass_on_stack
)
1704 rtx mem
= validize_mem (args
[i
].value
);
1706 /* Check for overlap with already clobbered argument area,
1707 providing that this has non-zero size. */
1710 || mem_overlaps_already_clobbered_arg_p
1711 (XEXP (args
[i
].value
, 0), size
)))
1712 *sibcall_failure
= 1;
1714 /* Handle a BLKmode that needs shifting. */
1715 if (nregs
== 1 && size
< UNITS_PER_WORD
1716 #ifdef BLOCK_REG_PADDING
1717 && args
[i
].locate
.where_pad
== downward
1723 rtx tem
= operand_subword_force (mem
, 0, args
[i
].mode
);
1724 rtx ri
= gen_rtx_REG (word_mode
, REGNO (reg
));
1725 rtx x
= gen_reg_rtx (word_mode
);
1726 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1727 enum tree_code dir
= BYTES_BIG_ENDIAN
? RSHIFT_EXPR
1730 emit_move_insn (x
, tem
);
1731 x
= expand_shift (dir
, word_mode
, x
, shift
, ri
, 1);
1733 emit_move_insn (ri
, x
);
1736 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
1739 /* When a parameter is a block, and perhaps in other cases, it is
1740 possible that it did a load from an argument slot that was
1741 already clobbered. */
1743 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
1744 *sibcall_failure
= 1;
1746 /* Handle calls that pass values in multiple non-contiguous
1747 locations. The Irix 6 ABI has examples of this. */
1748 if (GET_CODE (reg
) == PARALLEL
)
1749 use_group_regs (call_fusage
, reg
);
1750 else if (nregs
== -1)
1751 use_reg (call_fusage
, reg
);
1753 use_regs (call_fusage
, REGNO (reg
), nregs
);
1758 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1759 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1760 bytes, then we would need to push some additional bytes to pad the
1761 arguments. So, we compute an adjust to the stack pointer for an
1762 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1763 bytes. Then, when the arguments are pushed the stack will be perfectly
1764 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1765 be popped after the call. Returns the adjustment. */
1768 combine_pending_stack_adjustment_and_call (int unadjusted_args_size
,
1769 struct args_size
*args_size
,
1770 unsigned int preferred_unit_stack_boundary
)
1772 /* The number of bytes to pop so that the stack will be
1773 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1774 HOST_WIDE_INT adjustment
;
1775 /* The alignment of the stack after the arguments are pushed, if we
1776 just pushed the arguments without adjust the stack here. */
1777 unsigned HOST_WIDE_INT unadjusted_alignment
;
1779 unadjusted_alignment
1780 = ((stack_pointer_delta
+ unadjusted_args_size
)
1781 % preferred_unit_stack_boundary
);
1783 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1784 as possible -- leaving just enough left to cancel out the
1785 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1786 PENDING_STACK_ADJUST is non-negative, and congruent to
1787 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1789 /* Begin by trying to pop all the bytes. */
1790 unadjusted_alignment
1791 = (unadjusted_alignment
1792 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1793 adjustment
= pending_stack_adjust
;
1794 /* Push enough additional bytes that the stack will be aligned
1795 after the arguments are pushed. */
1796 if (preferred_unit_stack_boundary
> 1)
1798 if (unadjusted_alignment
> 0)
1799 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1801 adjustment
+= unadjusted_alignment
;
1804 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1805 bytes after the call. The right number is the entire
1806 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1807 by the arguments in the first place. */
1809 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1814 /* Scan X expression if it does not dereference any argument slots
1815 we already clobbered by tail call arguments (as noted in stored_args_map
1817 Return nonzero if X expression dereferences such argument slots,
1821 check_sibcall_argument_overlap_1 (rtx x
)
1830 code
= GET_CODE (x
);
1833 return mem_overlaps_already_clobbered_arg_p (XEXP (x
, 0),
1834 GET_MODE_SIZE (GET_MODE (x
)));
1836 /* Scan all subexpressions. */
1837 fmt
= GET_RTX_FORMAT (code
);
1838 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
1842 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
1845 else if (*fmt
== 'E')
1847 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
1848 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
1855 /* Scan sequence after INSN if it does not dereference any argument slots
1856 we already clobbered by tail call arguments (as noted in stored_args_map
1857 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1858 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1859 should be 0). Return nonzero if sequence after INSN dereferences such argument
1860 slots, zero otherwise. */
1863 check_sibcall_argument_overlap (rtx insn
, struct arg_data
*arg
, int mark_stored_args_map
)
1867 if (insn
== NULL_RTX
)
1868 insn
= get_insns ();
1870 insn
= NEXT_INSN (insn
);
1872 for (; insn
; insn
= NEXT_INSN (insn
))
1874 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
1877 if (mark_stored_args_map
)
1879 #ifdef ARGS_GROW_DOWNWARD
1880 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
1882 low
= arg
->locate
.slot_offset
.constant
;
1885 for (high
= low
+ arg
->locate
.size
.constant
; low
< high
; low
++)
1886 SET_BIT (stored_args_map
, low
);
1888 return insn
!= NULL_RTX
;
1891 /* Given that a function returns a value of mode MODE at the most
1892 significant end of hard register VALUE, shift VALUE left or right
1893 as specified by LEFT_P. Return true if some action was needed. */
1896 shift_return_value (enum machine_mode mode
, bool left_p
, rtx value
)
1898 HOST_WIDE_INT shift
;
1900 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
1901 shift
= GET_MODE_BITSIZE (GET_MODE (value
)) - GET_MODE_BITSIZE (mode
);
1905 /* Use ashr rather than lshr for right shifts. This is for the benefit
1906 of the MIPS port, which requires SImode values to be sign-extended
1907 when stored in 64-bit registers. */
1908 if (!force_expand_binop (GET_MODE (value
), left_p
? ashl_optab
: ashr_optab
,
1909 value
, GEN_INT (shift
), value
, 1, OPTAB_WIDEN
))
1914 /* If X is a likely-spilled register value, copy it to a pseudo
1915 register and return that register. Return X otherwise. */
1918 avoid_likely_spilled_reg (rtx x
)
1923 && HARD_REGISTER_P (x
)
1924 && targetm
.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x
))))
1926 /* Make sure that we generate a REG rather than a CONCAT.
1927 Moves into CONCATs can need nontrivial instructions,
1928 and the whole point of this function is to avoid
1929 using the hard register directly in such a situation. */
1930 generating_concat_p
= 0;
1931 new_rtx
= gen_reg_rtx (GET_MODE (x
));
1932 generating_concat_p
= 1;
1933 emit_move_insn (new_rtx
, x
);
1939 /* Generate all the code for a CALL_EXPR exp
1940 and return an rtx for its value.
1941 Store the value in TARGET (specified as an rtx) if convenient.
1942 If the value is stored in TARGET then TARGET is returned.
1943 If IGNORE is nonzero, then we ignore the value of the function call. */
1946 expand_call (tree exp
, rtx target
, int ignore
)
1948 /* Nonzero if we are currently expanding a call. */
1949 static int currently_expanding_call
= 0;
1951 /* RTX for the function to be called. */
1953 /* Sequence of insns to perform a normal "call". */
1954 rtx normal_call_insns
= NULL_RTX
;
1955 /* Sequence of insns to perform a tail "call". */
1956 rtx tail_call_insns
= NULL_RTX
;
1957 /* Data type of the function. */
1959 tree type_arg_types
;
1961 /* Declaration of the function being called,
1962 or 0 if the function is computed (not known by name). */
1964 /* The type of the function being called. */
1966 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
1969 /* Register in which non-BLKmode value will be returned,
1970 or 0 if no value or if value is BLKmode. */
1972 /* Address where we should return a BLKmode value;
1973 0 if value not BLKmode. */
1974 rtx structure_value_addr
= 0;
1975 /* Nonzero if that address is being passed by treating it as
1976 an extra, implicit first parameter. Otherwise,
1977 it is passed by being copied directly into struct_value_rtx. */
1978 int structure_value_addr_parm
= 0;
1979 /* Holds the value of implicit argument for the struct value. */
1980 tree structure_value_addr_value
= NULL_TREE
;
1981 /* Size of aggregate value wanted, or zero if none wanted
1982 or if we are using the non-reentrant PCC calling convention
1983 or expecting the value in registers. */
1984 HOST_WIDE_INT struct_value_size
= 0;
1985 /* Nonzero if called function returns an aggregate in memory PCC style,
1986 by returning the address of where to find it. */
1987 int pcc_struct_value
= 0;
1988 rtx struct_value
= 0;
1990 /* Number of actual parameters in this call, including struct value addr. */
1992 /* Number of named args. Args after this are anonymous ones
1993 and they must all go on the stack. */
1995 /* Number of complex actual arguments that need to be split. */
1996 int num_complex_actuals
= 0;
1998 /* Vector of information about each argument.
1999 Arguments are numbered in the order they will be pushed,
2000 not the order they are written. */
2001 struct arg_data
*args
;
2003 /* Total size in bytes of all the stack-parms scanned so far. */
2004 struct args_size args_size
;
2005 struct args_size adjusted_args_size
;
2006 /* Size of arguments before any adjustments (such as rounding). */
2007 int unadjusted_args_size
;
2008 /* Data on reg parms scanned so far. */
2009 CUMULATIVE_ARGS args_so_far_v
;
2010 cumulative_args_t args_so_far
;
2011 /* Nonzero if a reg parm has been scanned. */
2013 /* Nonzero if this is an indirect function call. */
2015 /* Nonzero if we must avoid push-insns in the args for this call.
2016 If stack space is allocated for register parameters, but not by the
2017 caller, then it is preallocated in the fixed part of the stack frame.
2018 So the entire argument block must then be preallocated (i.e., we
2019 ignore PUSH_ROUNDING in that case). */
2021 int must_preallocate
= !PUSH_ARGS
;
2023 /* Size of the stack reserved for parameter registers. */
2024 int reg_parm_stack_space
= 0;
2026 /* Address of space preallocated for stack parms
2027 (on machines that lack push insns), or 0 if space not preallocated. */
2030 /* Mask of ECF_ flags. */
2032 #ifdef REG_PARM_STACK_SPACE
2033 /* Define the boundary of the register parm stack space that needs to be
2035 int low_to_save
, high_to_save
;
2036 rtx save_area
= 0; /* Place that it is saved */
2039 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
2040 char *initial_stack_usage_map
= stack_usage_map
;
2041 char *stack_usage_map_buf
= NULL
;
2043 int old_stack_allocated
;
2045 /* State variables to track stack modifications. */
2046 rtx old_stack_level
= 0;
2047 int old_stack_arg_under_construction
= 0;
2048 int old_pending_adj
= 0;
2049 int old_inhibit_defer_pop
= inhibit_defer_pop
;
2051 /* Some stack pointer alterations we make are performed via
2052 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2053 which we then also need to save/restore along the way. */
2054 int old_stack_pointer_delta
= 0;
2057 tree addr
= CALL_EXPR_FN (exp
);
2059 /* The alignment of the stack, in bits. */
2060 unsigned HOST_WIDE_INT preferred_stack_boundary
;
2061 /* The alignment of the stack, in bytes. */
2062 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
2063 /* The static chain value to use for this call. */
2064 rtx static_chain_value
;
2065 /* See if this is "nothrow" function call. */
2066 if (TREE_NOTHROW (exp
))
2067 flags
|= ECF_NOTHROW
;
2069 /* See if we can find a DECL-node for the actual function, and get the
2070 function attributes (flags) from the function decl or type node. */
2071 fndecl
= get_callee_fndecl (exp
);
2074 fntype
= TREE_TYPE (fndecl
);
2075 flags
|= flags_from_decl_or_type (fndecl
);
2079 fntype
= TREE_TYPE (TREE_TYPE (addr
));
2080 flags
|= flags_from_decl_or_type (fntype
);
2082 rettype
= TREE_TYPE (exp
);
2084 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
2086 /* Warn if this value is an aggregate type,
2087 regardless of which calling convention we are using for it. */
2088 if (AGGREGATE_TYPE_P (rettype
))
2089 warning (OPT_Waggregate_return
, "function call has aggregate value");
2091 /* If the result of a non looping pure or const function call is
2092 ignored (or void), and none of its arguments are volatile, we can
2093 avoid expanding the call and just evaluate the arguments for
2095 if ((flags
& (ECF_CONST
| ECF_PURE
))
2096 && (!(flags
& ECF_LOOPING_CONST_OR_PURE
))
2097 && (ignore
|| target
== const0_rtx
2098 || TYPE_MODE (rettype
) == VOIDmode
))
2100 bool volatilep
= false;
2102 call_expr_arg_iterator iter
;
2104 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2105 if (TREE_THIS_VOLATILE (arg
))
2113 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2114 expand_expr (arg
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
2119 #ifdef REG_PARM_STACK_SPACE
2120 reg_parm_stack_space
= REG_PARM_STACK_SPACE (!fndecl
? fntype
: fndecl
);
2123 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
2124 && reg_parm_stack_space
> 0 && PUSH_ARGS
)
2125 must_preallocate
= 1;
2127 /* Set up a place to return a structure. */
2129 /* Cater to broken compilers. */
2130 if (aggregate_value_p (exp
, fntype
))
2132 /* This call returns a big structure. */
2133 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
2135 #ifdef PCC_STATIC_STRUCT_RETURN
2137 pcc_struct_value
= 1;
2139 #else /* not PCC_STATIC_STRUCT_RETURN */
2141 struct_value_size
= int_size_in_bytes (rettype
);
2143 if (target
&& MEM_P (target
) && CALL_EXPR_RETURN_SLOT_OPT (exp
))
2144 structure_value_addr
= XEXP (target
, 0);
2147 /* For variable-sized objects, we must be called with a target
2148 specified. If we were to allocate space on the stack here,
2149 we would have no way of knowing when to free it. */
2150 rtx d
= assign_temp (rettype
, 0, 1, 1);
2152 mark_temp_addr_taken (d
);
2153 structure_value_addr
= XEXP (d
, 0);
2157 #endif /* not PCC_STATIC_STRUCT_RETURN */
2160 /* Figure out the amount to which the stack should be aligned. */
2161 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2164 struct cgraph_rtl_info
*i
= cgraph_rtl_info (fndecl
);
2165 /* Without automatic stack alignment, we can't increase preferred
2166 stack boundary. With automatic stack alignment, it is
2167 unnecessary since unless we can guarantee that all callers will
2168 align the outgoing stack properly, callee has to align its
2171 && i
->preferred_incoming_stack_boundary
2172 && i
->preferred_incoming_stack_boundary
< preferred_stack_boundary
)
2173 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
2176 /* Operand 0 is a pointer-to-function; get the type of the function. */
2177 funtype
= TREE_TYPE (addr
);
2178 gcc_assert (POINTER_TYPE_P (funtype
));
2179 funtype
= TREE_TYPE (funtype
);
2181 /* Count whether there are actual complex arguments that need to be split
2182 into their real and imaginary parts. Munge the type_arg_types
2183 appropriately here as well. */
2184 if (targetm
.calls
.split_complex_arg
)
2186 call_expr_arg_iterator iter
;
2188 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2190 tree type
= TREE_TYPE (arg
);
2191 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
2192 && targetm
.calls
.split_complex_arg (type
))
2193 num_complex_actuals
++;
2195 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
2198 type_arg_types
= TYPE_ARG_TYPES (funtype
);
2200 if (flags
& ECF_MAY_BE_ALLOCA
)
2201 cfun
->calls_alloca
= 1;
2203 /* If struct_value_rtx is 0, it means pass the address
2204 as if it were an extra parameter. Put the argument expression
2205 in structure_value_addr_value. */
2206 if (structure_value_addr
&& struct_value
== 0)
2208 /* If structure_value_addr is a REG other than
2209 virtual_outgoing_args_rtx, we can use always use it. If it
2210 is not a REG, we must always copy it into a register.
2211 If it is virtual_outgoing_args_rtx, we must copy it to another
2212 register in some cases. */
2213 rtx temp
= (!REG_P (structure_value_addr
)
2214 || (ACCUMULATE_OUTGOING_ARGS
2215 && stack_arg_under_construction
2216 && structure_value_addr
== virtual_outgoing_args_rtx
)
2217 ? copy_addr_to_reg (convert_memory_address
2218 (Pmode
, structure_value_addr
))
2219 : structure_value_addr
);
2221 structure_value_addr_value
=
2222 make_tree (build_pointer_type (TREE_TYPE (funtype
)), temp
);
2223 structure_value_addr_parm
= 1;
2226 /* Count the arguments and set NUM_ACTUALS. */
2228 call_expr_nargs (exp
) + num_complex_actuals
+ structure_value_addr_parm
;
2230 /* Compute number of named args.
2231 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2233 if (type_arg_types
!= 0)
2235 = (list_length (type_arg_types
)
2236 /* Count the struct value address, if it is passed as a parm. */
2237 + structure_value_addr_parm
);
2239 /* If we know nothing, treat all args as named. */
2240 n_named_args
= num_actuals
;
2242 /* Start updating where the next arg would go.
2244 On some machines (such as the PA) indirect calls have a different
2245 calling convention than normal calls. The fourth argument in
2246 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2248 INIT_CUMULATIVE_ARGS (args_so_far_v
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
2249 args_so_far
= pack_cumulative_args (&args_so_far_v
);
2251 /* Now possibly adjust the number of named args.
2252 Normally, don't include the last named arg if anonymous args follow.
2253 We do include the last named arg if
2254 targetm.calls.strict_argument_naming() returns nonzero.
2255 (If no anonymous args follow, the result of list_length is actually
2256 one too large. This is harmless.)
2258 If targetm.calls.pretend_outgoing_varargs_named() returns
2259 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2260 this machine will be able to place unnamed args that were passed
2261 in registers into the stack. So treat all args as named. This
2262 allows the insns emitting for a specific argument list to be
2263 independent of the function declaration.
2265 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2266 we do not have any reliable way to pass unnamed args in
2267 registers, so we must force them into memory. */
2269 if (type_arg_types
!= 0
2270 && targetm
.calls
.strict_argument_naming (args_so_far
))
2272 else if (type_arg_types
!= 0
2273 && ! targetm
.calls
.pretend_outgoing_varargs_named (args_so_far
))
2274 /* Don't include the last named arg. */
2277 /* Treat all args as named. */
2278 n_named_args
= num_actuals
;
2280 /* Make a vector to hold all the information about each arg. */
2281 args
= XALLOCAVEC (struct arg_data
, num_actuals
);
2282 memset (args
, 0, num_actuals
* sizeof (struct arg_data
));
2284 /* Build up entries in the ARGS array, compute the size of the
2285 arguments into ARGS_SIZE, etc. */
2286 initialize_argument_information (num_actuals
, args
, &args_size
,
2288 structure_value_addr_value
, fndecl
, fntype
,
2289 args_so_far
, reg_parm_stack_space
,
2290 &old_stack_level
, &old_pending_adj
,
2291 &must_preallocate
, &flags
,
2292 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
2295 must_preallocate
= 1;
2297 /* Now make final decision about preallocating stack space. */
2298 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2302 /* If the structure value address will reference the stack pointer, we
2303 must stabilize it. We don't need to do this if we know that we are
2304 not going to adjust the stack pointer in processing this call. */
2306 if (structure_value_addr
2307 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2308 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2309 structure_value_addr
))
2311 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2312 structure_value_addr
= copy_to_reg (structure_value_addr
);
2314 /* Tail calls can make things harder to debug, and we've traditionally
2315 pushed these optimizations into -O2. Don't try if we're already
2316 expanding a call, as that means we're an argument. Don't try if
2317 there's cleanups, as we know there's code to follow the call. */
2319 if (currently_expanding_call
++ != 0
2320 || !flag_optimize_sibling_calls
2322 || dbg_cnt (tail_call
) == false)
2325 /* Rest of purposes for tail call optimizations to fail. */
2327 #ifdef HAVE_sibcall_epilogue
2328 !HAVE_sibcall_epilogue
2333 /* Doing sibling call optimization needs some work, since
2334 structure_value_addr can be allocated on the stack.
2335 It does not seem worth the effort since few optimizable
2336 sibling calls will return a structure. */
2337 || structure_value_addr
!= NULL_RTX
2338 #ifdef REG_PARM_STACK_SPACE
2339 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2340 || (OUTGOING_REG_PARM_STACK_SPACE (funtype
)
2341 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl
)))
2342 || (reg_parm_stack_space
!= REG_PARM_STACK_SPACE (fndecl
))
2344 /* Check whether the target is able to optimize the call
2346 || !targetm
.function_ok_for_sibcall (fndecl
, exp
)
2347 /* Functions that do not return exactly once may not be sibcall
2349 || (flags
& (ECF_RETURNS_TWICE
| ECF_NORETURN
))
2350 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
)))
2351 /* If the called function is nested in the current one, it might access
2352 some of the caller's arguments, but could clobber them beforehand if
2353 the argument areas are shared. */
2354 || (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
2355 /* If this function requires more stack slots than the current
2356 function, we cannot change it into a sibling call.
2357 crtl->args.pretend_args_size is not part of the
2358 stack allocated by our caller. */
2359 || args_size
.constant
> (crtl
->args
.size
2360 - crtl
->args
.pretend_args_size
)
2361 /* If the callee pops its own arguments, then it must pop exactly
2362 the same number of arguments as the current function. */
2363 || (targetm
.calls
.return_pops_args (fndecl
, funtype
, args_size
.constant
)
2364 != targetm
.calls
.return_pops_args (current_function_decl
,
2365 TREE_TYPE (current_function_decl
),
2367 || !lang_hooks
.decls
.ok_for_sibcall (fndecl
))
2370 /* Check if caller and callee disagree in promotion of function
2374 enum machine_mode caller_mode
, caller_promoted_mode
;
2375 enum machine_mode callee_mode
, callee_promoted_mode
;
2376 int caller_unsignedp
, callee_unsignedp
;
2377 tree caller_res
= DECL_RESULT (current_function_decl
);
2379 caller_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (caller_res
));
2380 caller_mode
= DECL_MODE (caller_res
);
2381 callee_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (funtype
));
2382 callee_mode
= TYPE_MODE (TREE_TYPE (funtype
));
2383 caller_promoted_mode
2384 = promote_function_mode (TREE_TYPE (caller_res
), caller_mode
,
2386 TREE_TYPE (current_function_decl
), 1);
2387 callee_promoted_mode
2388 = promote_function_mode (TREE_TYPE (funtype
), callee_mode
,
2391 if (caller_mode
!= VOIDmode
2392 && (caller_promoted_mode
!= callee_promoted_mode
2393 || ((caller_mode
!= caller_promoted_mode
2394 || callee_mode
!= callee_promoted_mode
)
2395 && (caller_unsignedp
!= callee_unsignedp
2396 || GET_MODE_BITSIZE (caller_mode
)
2397 < GET_MODE_BITSIZE (callee_mode
)))))
2401 /* Ensure current function's preferred stack boundary is at least
2402 what we need. Stack alignment may also increase preferred stack
2404 if (crtl
->preferred_stack_boundary
< preferred_stack_boundary
)
2405 crtl
->preferred_stack_boundary
= preferred_stack_boundary
;
2407 preferred_stack_boundary
= crtl
->preferred_stack_boundary
;
2409 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2411 /* We want to make two insn chains; one for a sibling call, the other
2412 for a normal call. We will select one of the two chains after
2413 initial RTL generation is complete. */
2414 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
2416 int sibcall_failure
= 0;
2417 /* We want to emit any pending stack adjustments before the tail
2418 recursion "call". That way we know any adjustment after the tail
2419 recursion call can be ignored if we indeed use the tail
2421 int save_pending_stack_adjust
= 0;
2422 int save_stack_pointer_delta
= 0;
2424 rtx before_call
, next_arg_reg
, after_args
;
2428 /* State variables we need to save and restore between
2430 save_pending_stack_adjust
= pending_stack_adjust
;
2431 save_stack_pointer_delta
= stack_pointer_delta
;
2434 flags
&= ~ECF_SIBCALL
;
2436 flags
|= ECF_SIBCALL
;
2438 /* Other state variables that we must reinitialize each time
2439 through the loop (that are not initialized by the loop itself). */
2443 /* Start a new sequence for the normal call case.
2445 From this point on, if the sibling call fails, we want to set
2446 sibcall_failure instead of continuing the loop. */
2449 /* Don't let pending stack adjusts add up to too much.
2450 Also, do all pending adjustments now if there is any chance
2451 this might be a call to alloca or if we are expanding a sibling
2453 Also do the adjustments before a throwing call, otherwise
2454 exception handling can fail; PR 19225. */
2455 if (pending_stack_adjust
>= 32
2456 || (pending_stack_adjust
> 0
2457 && (flags
& ECF_MAY_BE_ALLOCA
))
2458 || (pending_stack_adjust
> 0
2459 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
2461 do_pending_stack_adjust ();
2463 /* Precompute any arguments as needed. */
2465 precompute_arguments (num_actuals
, args
);
2467 /* Now we are about to start emitting insns that can be deleted
2468 if a libcall is deleted. */
2469 if (pass
&& (flags
& ECF_MALLOC
))
2472 if (pass
== 0 && crtl
->stack_protect_guard
)
2473 stack_protect_epilogue ();
2475 adjusted_args_size
= args_size
;
2476 /* Compute the actual size of the argument block required. The variable
2477 and constant sizes must be combined, the size may have to be rounded,
2478 and there may be a minimum required size. When generating a sibcall
2479 pattern, do not round up, since we'll be re-using whatever space our
2481 unadjusted_args_size
2482 = compute_argument_block_size (reg_parm_stack_space
,
2483 &adjusted_args_size
,
2486 : preferred_stack_boundary
));
2488 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2490 /* The argument block when performing a sibling call is the
2491 incoming argument block. */
2494 argblock
= crtl
->args
.internal_arg_pointer
;
2496 #ifdef STACK_GROWS_DOWNWARD
2497 = plus_constant (argblock
, crtl
->args
.pretend_args_size
);
2499 = plus_constant (argblock
, -crtl
->args
.pretend_args_size
);
2501 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2502 sbitmap_zero (stored_args_map
);
2505 /* If we have no actual push instructions, or shouldn't use them,
2506 make space for all args right now. */
2507 else if (adjusted_args_size
.var
!= 0)
2509 if (old_stack_level
== 0)
2511 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
2512 old_stack_pointer_delta
= stack_pointer_delta
;
2513 old_pending_adj
= pending_stack_adjust
;
2514 pending_stack_adjust
= 0;
2515 /* stack_arg_under_construction says whether a stack arg is
2516 being constructed at the old stack level. Pushing the stack
2517 gets a clean outgoing argument block. */
2518 old_stack_arg_under_construction
= stack_arg_under_construction
;
2519 stack_arg_under_construction
= 0;
2521 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2522 if (flag_stack_usage_info
)
2523 current_function_has_unbounded_dynamic_stack_size
= 1;
2527 /* Note that we must go through the motions of allocating an argument
2528 block even if the size is zero because we may be storing args
2529 in the area reserved for register arguments, which may be part of
2532 int needed
= adjusted_args_size
.constant
;
2534 /* Store the maximum argument space used. It will be pushed by
2535 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2538 if (needed
> crtl
->outgoing_args_size
)
2539 crtl
->outgoing_args_size
= needed
;
2541 if (must_preallocate
)
2543 if (ACCUMULATE_OUTGOING_ARGS
)
2545 /* Since the stack pointer will never be pushed, it is
2546 possible for the evaluation of a parm to clobber
2547 something we have already written to the stack.
2548 Since most function calls on RISC machines do not use
2549 the stack, this is uncommon, but must work correctly.
2551 Therefore, we save any area of the stack that was already
2552 written and that we are using. Here we set up to do this
2553 by making a new stack usage map from the old one. The
2554 actual save will be done by store_one_arg.
2556 Another approach might be to try to reorder the argument
2557 evaluations to avoid this conflicting stack usage. */
2559 /* Since we will be writing into the entire argument area,
2560 the map must be allocated for its entire size, not just
2561 the part that is the responsibility of the caller. */
2562 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2563 needed
+= reg_parm_stack_space
;
2565 #ifdef ARGS_GROW_DOWNWARD
2566 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2569 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2572 free (stack_usage_map_buf
);
2573 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
2574 stack_usage_map
= stack_usage_map_buf
;
2576 if (initial_highest_arg_in_use
)
2577 memcpy (stack_usage_map
, initial_stack_usage_map
,
2578 initial_highest_arg_in_use
);
2580 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2581 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2582 (highest_outgoing_arg_in_use
2583 - initial_highest_arg_in_use
));
2586 /* The address of the outgoing argument list must not be
2587 copied to a register here, because argblock would be left
2588 pointing to the wrong place after the call to
2589 allocate_dynamic_stack_space below. */
2591 argblock
= virtual_outgoing_args_rtx
;
2595 if (inhibit_defer_pop
== 0)
2597 /* Try to reuse some or all of the pending_stack_adjust
2598 to get this space. */
2600 = (combine_pending_stack_adjustment_and_call
2601 (unadjusted_args_size
,
2602 &adjusted_args_size
,
2603 preferred_unit_stack_boundary
));
2605 /* combine_pending_stack_adjustment_and_call computes
2606 an adjustment before the arguments are allocated.
2607 Account for them and see whether or not the stack
2608 needs to go up or down. */
2609 needed
= unadjusted_args_size
- needed
;
2613 /* We're releasing stack space. */
2614 /* ??? We can avoid any adjustment at all if we're
2615 already aligned. FIXME. */
2616 pending_stack_adjust
= -needed
;
2617 do_pending_stack_adjust ();
2621 /* We need to allocate space. We'll do that in
2622 push_block below. */
2623 pending_stack_adjust
= 0;
2626 /* Special case this because overhead of `push_block' in
2627 this case is non-trivial. */
2629 argblock
= virtual_outgoing_args_rtx
;
2632 argblock
= push_block (GEN_INT (needed
), 0, 0);
2633 #ifdef ARGS_GROW_DOWNWARD
2634 argblock
= plus_constant (argblock
, needed
);
2638 /* We only really need to call `copy_to_reg' in the case
2639 where push insns are going to be used to pass ARGBLOCK
2640 to a function call in ARGS. In that case, the stack
2641 pointer changes value from the allocation point to the
2642 call point, and hence the value of
2643 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2644 as well always do it. */
2645 argblock
= copy_to_reg (argblock
);
2650 if (ACCUMULATE_OUTGOING_ARGS
)
2652 /* The save/restore code in store_one_arg handles all
2653 cases except one: a constructor call (including a C
2654 function returning a BLKmode struct) to initialize
2656 if (stack_arg_under_construction
)
2659 = GEN_INT (adjusted_args_size
.constant
2660 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
2661 : TREE_TYPE (fndecl
))) ? 0
2662 : reg_parm_stack_space
));
2663 if (old_stack_level
== 0)
2665 emit_stack_save (SAVE_BLOCK
, &old_stack_level
);
2666 old_stack_pointer_delta
= stack_pointer_delta
;
2667 old_pending_adj
= pending_stack_adjust
;
2668 pending_stack_adjust
= 0;
2669 /* stack_arg_under_construction says whether a stack
2670 arg is being constructed at the old stack level.
2671 Pushing the stack gets a clean outgoing argument
2673 old_stack_arg_under_construction
2674 = stack_arg_under_construction
;
2675 stack_arg_under_construction
= 0;
2676 /* Make a new map for the new argument list. */
2677 free (stack_usage_map_buf
);
2678 stack_usage_map_buf
= XCNEWVEC (char, highest_outgoing_arg_in_use
);
2679 stack_usage_map
= stack_usage_map_buf
;
2680 highest_outgoing_arg_in_use
= 0;
2682 /* We can pass TRUE as the 4th argument because we just
2683 saved the stack pointer and will restore it right after
2685 allocate_dynamic_stack_space (push_size
, 0,
2686 BIGGEST_ALIGNMENT
, true);
2689 /* If argument evaluation might modify the stack pointer,
2690 copy the address of the argument list to a register. */
2691 for (i
= 0; i
< num_actuals
; i
++)
2692 if (args
[i
].pass_on_stack
)
2694 argblock
= copy_addr_to_reg (argblock
);
2699 compute_argument_addresses (args
, argblock
, num_actuals
);
2701 /* If we push args individually in reverse order, perform stack alignment
2702 before the first push (the last arg). */
2703 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2704 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2706 /* When the stack adjustment is pending, we get better code
2707 by combining the adjustments. */
2708 if (pending_stack_adjust
2709 && ! inhibit_defer_pop
)
2711 pending_stack_adjust
2712 = (combine_pending_stack_adjustment_and_call
2713 (unadjusted_args_size
,
2714 &adjusted_args_size
,
2715 preferred_unit_stack_boundary
));
2716 do_pending_stack_adjust ();
2718 else if (argblock
== 0)
2719 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2720 - unadjusted_args_size
));
2722 /* Now that the stack is properly aligned, pops can't safely
2723 be deferred during the evaluation of the arguments. */
2726 /* Record the maximum pushed stack space size. We need to delay
2727 doing it this far to take into account the optimization done
2728 by combine_pending_stack_adjustment_and_call. */
2729 if (flag_stack_usage_info
2730 && !ACCUMULATE_OUTGOING_ARGS
2732 && adjusted_args_size
.var
== 0)
2734 int pushed
= adjusted_args_size
.constant
+ pending_stack_adjust
;
2735 if (pushed
> current_function_pushed_stack_size
)
2736 current_function_pushed_stack_size
= pushed
;
2739 funexp
= rtx_for_function_call (fndecl
, addr
);
2741 /* Figure out the register where the value, if any, will come back. */
2743 if (TYPE_MODE (rettype
) != VOIDmode
2744 && ! structure_value_addr
)
2746 if (pcc_struct_value
)
2747 valreg
= hard_function_value (build_pointer_type (rettype
),
2748 fndecl
, NULL
, (pass
== 0));
2750 valreg
= hard_function_value (rettype
, fndecl
, fntype
,
2753 /* If VALREG is a PARALLEL whose first member has a zero
2754 offset, use that. This is for targets such as m68k that
2755 return the same value in multiple places. */
2756 if (GET_CODE (valreg
) == PARALLEL
)
2758 rtx elem
= XVECEXP (valreg
, 0, 0);
2759 rtx where
= XEXP (elem
, 0);
2760 rtx offset
= XEXP (elem
, 1);
2761 if (offset
== const0_rtx
2762 && GET_MODE (where
) == GET_MODE (valreg
))
2767 /* Precompute all register parameters. It isn't safe to compute anything
2768 once we have started filling any specific hard regs. */
2769 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2771 if (CALL_EXPR_STATIC_CHAIN (exp
))
2772 static_chain_value
= expand_normal (CALL_EXPR_STATIC_CHAIN (exp
));
2774 static_chain_value
= 0;
2776 #ifdef REG_PARM_STACK_SPACE
2777 /* Save the fixed argument area if it's part of the caller's frame and
2778 is clobbered by argument setup for this call. */
2779 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2780 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2781 &low_to_save
, &high_to_save
);
2784 /* Now store (and compute if necessary) all non-register parms.
2785 These come before register parms, since they can require block-moves,
2786 which could clobber the registers used for register parms.
2787 Parms which have partial registers are not stored here,
2788 but we do preallocate space here if they want that. */
2790 for (i
= 0; i
< num_actuals
; i
++)
2792 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2794 rtx before_arg
= get_last_insn ();
2796 if (store_one_arg (&args
[i
], argblock
, flags
,
2797 adjusted_args_size
.var
!= 0,
2798 reg_parm_stack_space
)
2800 && check_sibcall_argument_overlap (before_arg
,
2802 sibcall_failure
= 1;
2806 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
2807 gen_rtx_USE (VOIDmode
,
2812 /* If we have a parm that is passed in registers but not in memory
2813 and whose alignment does not permit a direct copy into registers,
2814 make a group of pseudos that correspond to each register that we
2816 if (STRICT_ALIGNMENT
)
2817 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2819 /* Now store any partially-in-registers parm.
2820 This is the last place a block-move can happen. */
2822 for (i
= 0; i
< num_actuals
; i
++)
2823 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2825 rtx before_arg
= get_last_insn ();
2827 if (store_one_arg (&args
[i
], argblock
, flags
,
2828 adjusted_args_size
.var
!= 0,
2829 reg_parm_stack_space
)
2831 && check_sibcall_argument_overlap (before_arg
,
2833 sibcall_failure
= 1;
2836 /* If we pushed args in forward order, perform stack alignment
2837 after pushing the last arg. */
2838 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
2839 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2840 - unadjusted_args_size
));
2842 /* If register arguments require space on the stack and stack space
2843 was not preallocated, allocate stack space here for arguments
2844 passed in registers. */
2845 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
2846 && !ACCUMULATE_OUTGOING_ARGS
2847 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
2848 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
2850 /* Pass the function the address in which to return a
2852 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
2854 structure_value_addr
2855 = convert_memory_address (Pmode
, structure_value_addr
);
2856 emit_move_insn (struct_value
,
2858 force_operand (structure_value_addr
,
2861 if (REG_P (struct_value
))
2862 use_reg (&call_fusage
, struct_value
);
2865 after_args
= get_last_insn ();
2866 funexp
= prepare_call_address (fndecl
, funexp
, static_chain_value
,
2867 &call_fusage
, reg_parm_seen
, pass
== 0);
2869 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
2870 pass
== 0, &sibcall_failure
);
2872 /* Save a pointer to the last insn before the call, so that we can
2873 later safely search backwards to find the CALL_INSN. */
2874 before_call
= get_last_insn ();
2876 /* Set up next argument register. For sibling calls on machines
2877 with register windows this should be the incoming register. */
2879 next_arg_reg
= targetm
.calls
.function_incoming_arg (args_so_far
,
2884 next_arg_reg
= targetm
.calls
.function_arg (args_so_far
,
2885 VOIDmode
, void_type_node
,
2888 /* All arguments and registers used for the call must be set up by
2891 /* Stack must be properly aligned now. */
2893 || !(stack_pointer_delta
% preferred_unit_stack_boundary
));
2895 /* Generate the actual call instruction. */
2896 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
2897 adjusted_args_size
.constant
, struct_value_size
,
2898 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
2899 flags
, args_so_far
);
2901 /* If the call setup or the call itself overlaps with anything
2902 of the argument setup we probably clobbered our call address.
2903 In that case we can't do sibcalls. */
2905 && check_sibcall_argument_overlap (after_args
, 0, 0))
2906 sibcall_failure
= 1;
2908 /* If a non-BLKmode value is returned at the most significant end
2909 of a register, shift the register right by the appropriate amount
2910 and update VALREG accordingly. BLKmode values are handled by the
2911 group load/store machinery below. */
2912 if (!structure_value_addr
2913 && !pcc_struct_value
2914 && TYPE_MODE (rettype
) != BLKmode
2915 && targetm
.calls
.return_in_msb (rettype
))
2917 if (shift_return_value (TYPE_MODE (rettype
), false, valreg
))
2918 sibcall_failure
= 1;
2919 valreg
= gen_rtx_REG (TYPE_MODE (rettype
), REGNO (valreg
));
2922 if (pass
&& (flags
& ECF_MALLOC
))
2924 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2927 /* The return value from a malloc-like function is a pointer. */
2928 if (TREE_CODE (rettype
) == POINTER_TYPE
)
2929 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
2931 emit_move_insn (temp
, valreg
);
2933 /* The return value from a malloc-like function can not alias
2935 last
= get_last_insn ();
2936 add_reg_note (last
, REG_NOALIAS
, temp
);
2938 /* Write out the sequence. */
2939 insns
= get_insns ();
2945 /* For calls to `setjmp', etc., inform
2946 function.c:setjmp_warnings that it should complain if
2947 nonvolatile values are live. For functions that cannot
2948 return, inform flow that control does not fall through. */
2950 if ((flags
& ECF_NORETURN
) || pass
== 0)
2952 /* The barrier must be emitted
2953 immediately after the CALL_INSN. Some ports emit more
2954 than just a CALL_INSN above, so we must search for it here. */
2956 rtx last
= get_last_insn ();
2957 while (!CALL_P (last
))
2959 last
= PREV_INSN (last
);
2960 /* There was no CALL_INSN? */
2961 gcc_assert (last
!= before_call
);
2964 emit_barrier_after (last
);
2966 /* Stack adjustments after a noreturn call are dead code.
2967 However when NO_DEFER_POP is in effect, we must preserve
2968 stack_pointer_delta. */
2969 if (inhibit_defer_pop
== 0)
2971 stack_pointer_delta
= old_stack_allocated
;
2972 pending_stack_adjust
= 0;
2976 /* If value type not void, return an rtx for the value. */
2978 if (TYPE_MODE (rettype
) == VOIDmode
2980 target
= const0_rtx
;
2981 else if (structure_value_addr
)
2983 if (target
== 0 || !MEM_P (target
))
2986 = gen_rtx_MEM (TYPE_MODE (rettype
),
2987 memory_address (TYPE_MODE (rettype
),
2988 structure_value_addr
));
2989 set_mem_attributes (target
, rettype
, 1);
2992 else if (pcc_struct_value
)
2994 /* This is the special C++ case where we need to
2995 know what the true target was. We take care to
2996 never use this value more than once in one expression. */
2997 target
= gen_rtx_MEM (TYPE_MODE (rettype
),
2998 copy_to_reg (valreg
));
2999 set_mem_attributes (target
, rettype
, 1);
3001 /* Handle calls that return values in multiple non-contiguous locations.
3002 The Irix 6 ABI has examples of this. */
3003 else if (GET_CODE (valreg
) == PARALLEL
)
3007 /* This will only be assigned once, so it can be readonly. */
3008 tree nt
= build_qualified_type (rettype
,
3009 (TYPE_QUALS (rettype
)
3010 | TYPE_QUAL_CONST
));
3012 target
= assign_temp (nt
, 0, 1, 1);
3015 if (! rtx_equal_p (target
, valreg
))
3016 emit_group_store (target
, valreg
, rettype
,
3017 int_size_in_bytes (rettype
));
3019 /* We can not support sibling calls for this case. */
3020 sibcall_failure
= 1;
3023 && GET_MODE (target
) == TYPE_MODE (rettype
)
3024 && GET_MODE (target
) == GET_MODE (valreg
))
3026 bool may_overlap
= false;
3028 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
3029 reg to a plain register. */
3030 if (!REG_P (target
) || HARD_REGISTER_P (target
))
3031 valreg
= avoid_likely_spilled_reg (valreg
);
3033 /* If TARGET is a MEM in the argument area, and we have
3034 saved part of the argument area, then we can't store
3035 directly into TARGET as it may get overwritten when we
3036 restore the argument save area below. Don't work too
3037 hard though and simply force TARGET to a register if it
3038 is a MEM; the optimizer is quite likely to sort it out. */
3039 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
3040 for (i
= 0; i
< num_actuals
; i
++)
3041 if (args
[i
].save_area
)
3048 target
= copy_to_reg (valreg
);
3051 /* TARGET and VALREG cannot be equal at this point
3052 because the latter would not have
3053 REG_FUNCTION_VALUE_P true, while the former would if
3054 it were referring to the same register.
3056 If they refer to the same register, this move will be
3057 a no-op, except when function inlining is being
3059 emit_move_insn (target
, valreg
);
3061 /* If we are setting a MEM, this code must be executed.
3062 Since it is emitted after the call insn, sibcall
3063 optimization cannot be performed in that case. */
3065 sibcall_failure
= 1;
3068 else if (TYPE_MODE (rettype
) == BLKmode
)
3071 if (GET_MODE (val
) != BLKmode
)
3072 val
= avoid_likely_spilled_reg (val
);
3073 target
= copy_blkmode_from_reg (target
, val
, rettype
);
3075 /* We can not support sibling calls for this case. */
3076 sibcall_failure
= 1;
3079 target
= copy_to_reg (avoid_likely_spilled_reg (valreg
));
3081 /* If we promoted this return value, make the proper SUBREG.
3082 TARGET might be const0_rtx here, so be careful. */
3084 && TYPE_MODE (rettype
) != BLKmode
3085 && GET_MODE (target
) != TYPE_MODE (rettype
))
3087 tree type
= rettype
;
3088 int unsignedp
= TYPE_UNSIGNED (type
);
3090 enum machine_mode pmode
;
3092 /* Ensure we promote as expected, and get the new unsignedness. */
3093 pmode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
3095 gcc_assert (GET_MODE (target
) == pmode
);
3097 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
3098 && (GET_MODE_SIZE (GET_MODE (target
))
3099 > GET_MODE_SIZE (TYPE_MODE (type
))))
3101 offset
= GET_MODE_SIZE (GET_MODE (target
))
3102 - GET_MODE_SIZE (TYPE_MODE (type
));
3103 if (! BYTES_BIG_ENDIAN
)
3104 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
3105 else if (! WORDS_BIG_ENDIAN
)
3106 offset
%= UNITS_PER_WORD
;
3109 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
3110 SUBREG_PROMOTED_VAR_P (target
) = 1;
3111 SUBREG_PROMOTED_UNSIGNED_SET (target
, unsignedp
);
3114 /* If size of args is variable or this was a constructor call for a stack
3115 argument, restore saved stack-pointer value. */
3117 if (old_stack_level
)
3119 emit_stack_restore (SAVE_BLOCK
, old_stack_level
);
3120 stack_pointer_delta
= old_stack_pointer_delta
;
3121 pending_stack_adjust
= old_pending_adj
;
3122 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
3123 stack_arg_under_construction
= old_stack_arg_under_construction
;
3124 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3125 stack_usage_map
= initial_stack_usage_map
;
3126 sibcall_failure
= 1;
3128 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
3130 #ifdef REG_PARM_STACK_SPACE
3132 restore_fixed_argument_area (save_area
, argblock
,
3133 high_to_save
, low_to_save
);
3136 /* If we saved any argument areas, restore them. */
3137 for (i
= 0; i
< num_actuals
; i
++)
3138 if (args
[i
].save_area
)
3140 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
3142 = gen_rtx_MEM (save_mode
,
3143 memory_address (save_mode
,
3144 XEXP (args
[i
].stack_slot
, 0)));
3146 if (save_mode
!= BLKmode
)
3147 emit_move_insn (stack_area
, args
[i
].save_area
);
3149 emit_block_move (stack_area
, args
[i
].save_area
,
3150 GEN_INT (args
[i
].locate
.size
.constant
),
3151 BLOCK_OP_CALL_PARM
);
3154 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3155 stack_usage_map
= initial_stack_usage_map
;
3158 /* If this was alloca, record the new stack level for nonlocal gotos.
3159 Check for the handler slots since we might not have a save area
3160 for non-local gotos. */
3162 if ((flags
& ECF_MAY_BE_ALLOCA
) && cfun
->nonlocal_goto_save_area
!= 0)
3163 update_nonlocal_goto_save_area ();
3165 /* Free up storage we no longer need. */
3166 for (i
= 0; i
< num_actuals
; ++i
)
3167 free (args
[i
].aligned_regs
);
3169 insns
= get_insns ();
3174 tail_call_insns
= insns
;
3176 /* Restore the pending stack adjustment now that we have
3177 finished generating the sibling call sequence. */
3179 pending_stack_adjust
= save_pending_stack_adjust
;
3180 stack_pointer_delta
= save_stack_pointer_delta
;
3182 /* Prepare arg structure for next iteration. */
3183 for (i
= 0; i
< num_actuals
; i
++)
3186 args
[i
].aligned_regs
= 0;
3190 sbitmap_free (stored_args_map
);
3194 normal_call_insns
= insns
;
3196 /* Verify that we've deallocated all the stack we used. */
3197 gcc_assert ((flags
& ECF_NORETURN
)
3198 || (old_stack_allocated
3199 == stack_pointer_delta
- pending_stack_adjust
));
3202 /* If something prevents making this a sibling call,
3203 zero out the sequence. */
3204 if (sibcall_failure
)
3205 tail_call_insns
= NULL_RTX
;
3210 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3211 arguments too, as argument area is now clobbered by the call. */
3212 if (tail_call_insns
)
3214 emit_insn (tail_call_insns
);
3215 crtl
->tail_call_emit
= true;
3218 emit_insn (normal_call_insns
);
3220 currently_expanding_call
--;
3222 free (stack_usage_map_buf
);
3227 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3228 this function's incoming arguments.
3230 At the start of RTL generation we know the only REG_EQUIV notes
3231 in the rtl chain are those for incoming arguments, so we can look
3232 for REG_EQUIV notes between the start of the function and the
3233 NOTE_INSN_FUNCTION_BEG.
3235 This is (slight) overkill. We could keep track of the highest
3236 argument we clobber and be more selective in removing notes, but it
3237 does not seem to be worth the effort. */
3240 fixup_tail_calls (void)
3244 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
3248 /* There are never REG_EQUIV notes for the incoming arguments
3249 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3251 && NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
)
3254 note
= find_reg_note (insn
, REG_EQUIV
, 0);
3256 remove_note (insn
, note
);
3257 note
= find_reg_note (insn
, REG_EQUIV
, 0);
3262 /* Traverse a list of TYPES and expand all complex types into their
3265 split_complex_types (tree types
)
3269 /* Before allocating memory, check for the common case of no complex. */
3270 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3272 tree type
= TREE_VALUE (p
);
3273 if (TREE_CODE (type
) == COMPLEX_TYPE
3274 && targetm
.calls
.split_complex_arg (type
))
3280 types
= copy_list (types
);
3282 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3284 tree complex_type
= TREE_VALUE (p
);
3286 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
3287 && targetm
.calls
.split_complex_arg (complex_type
))
3291 /* Rewrite complex type with component type. */
3292 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
3293 next
= TREE_CHAIN (p
);
3295 /* Add another component type for the imaginary part. */
3296 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
3297 TREE_CHAIN (p
) = imag
;
3298 TREE_CHAIN (imag
) = next
;
3300 /* Skip the newly created node. */
3308 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3309 The RETVAL parameter specifies whether return value needs to be saved, other
3310 parameters are documented in the emit_library_call function below. */
3313 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
3314 enum libcall_type fn_type
,
3315 enum machine_mode outmode
, int nargs
, va_list p
)
3317 /* Total size in bytes of all the stack-parms scanned so far. */
3318 struct args_size args_size
;
3319 /* Size of arguments before any adjustments (such as rounding). */
3320 struct args_size original_args_size
;
3323 /* Todo, choose the correct decl type of orgfun. Sadly this information
3324 isn't present here, so we default to native calling abi here. */
3325 tree fndecl ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
3326 tree fntype ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
3330 CUMULATIVE_ARGS args_so_far_v
;
3331 cumulative_args_t args_so_far
;
3335 enum machine_mode mode
;
3338 struct locate_and_pad_arg_data locate
;
3342 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3343 rtx call_fusage
= 0;
3346 int pcc_struct_value
= 0;
3347 int struct_value_size
= 0;
3349 int reg_parm_stack_space
= 0;
3352 tree tfom
; /* type_for_mode (outmode, 0) */
3354 #ifdef REG_PARM_STACK_SPACE
3355 /* Define the boundary of the register parm stack space that needs to be
3357 int low_to_save
= 0, high_to_save
= 0;
3358 rtx save_area
= 0; /* Place that it is saved. */
3361 /* Size of the stack reserved for parameter registers. */
3362 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3363 char *initial_stack_usage_map
= stack_usage_map
;
3364 char *stack_usage_map_buf
= NULL
;
3366 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
3368 #ifdef REG_PARM_STACK_SPACE
3369 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3372 /* By default, library functions can not throw. */
3373 flags
= ECF_NOTHROW
;
3386 flags
|= ECF_NORETURN
;
3389 flags
= ECF_NORETURN
;
3391 case LCT_RETURNS_TWICE
:
3392 flags
= ECF_RETURNS_TWICE
;
3397 /* Ensure current function's preferred stack boundary is at least
3399 if (crtl
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3400 crtl
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3402 /* If this kind of value comes back in memory,
3403 decide where in memory it should come back. */
3404 if (outmode
!= VOIDmode
)
3406 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
3407 if (aggregate_value_p (tfom
, 0))
3409 #ifdef PCC_STATIC_STRUCT_RETURN
3411 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
3412 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3413 pcc_struct_value
= 1;
3415 value
= gen_reg_rtx (outmode
);
3416 #else /* not PCC_STATIC_STRUCT_RETURN */
3417 struct_value_size
= GET_MODE_SIZE (outmode
);
3418 if (value
!= 0 && MEM_P (value
))
3421 mem_value
= assign_temp (tfom
, 0, 1, 1);
3423 /* This call returns a big structure. */
3424 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
3428 tfom
= void_type_node
;
3430 /* ??? Unfinished: must pass the memory address as an argument. */
3432 /* Copy all the libcall-arguments out of the varargs data
3433 and into a vector ARGVEC.
3435 Compute how to pass each argument. We only support a very small subset
3436 of the full argument passing conventions to limit complexity here since
3437 library functions shouldn't have many args. */
3439 argvec
= XALLOCAVEC (struct arg
, nargs
+ 1);
3440 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3442 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3443 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v
, outmode
, fun
);
3445 INIT_CUMULATIVE_ARGS (args_so_far_v
, NULL_TREE
, fun
, 0, nargs
);
3447 args_so_far
= pack_cumulative_args (&args_so_far_v
);
3449 args_size
.constant
= 0;
3456 /* If there's a structure value address to be passed,
3457 either pass it in the special place, or pass it as an extra argument. */
3458 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
3460 rtx addr
= XEXP (mem_value
, 0);
3464 /* Make sure it is a reasonable operand for a move or push insn. */
3465 if (!REG_P (addr
) && !MEM_P (addr
)
3466 && !(CONSTANT_P (addr
)
3467 && targetm
.legitimate_constant_p (Pmode
, addr
)))
3468 addr
= force_operand (addr
, NULL_RTX
);
3470 argvec
[count
].value
= addr
;
3471 argvec
[count
].mode
= Pmode
;
3472 argvec
[count
].partial
= 0;
3474 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
,
3475 Pmode
, NULL_TREE
, true);
3476 gcc_assert (targetm
.calls
.arg_partial_bytes (args_so_far
, Pmode
,
3477 NULL_TREE
, 1) == 0);
3479 locate_and_pad_parm (Pmode
, NULL_TREE
,
3480 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3483 argvec
[count
].reg
!= 0,
3485 0, NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3487 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3488 || reg_parm_stack_space
> 0)
3489 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3491 targetm
.calls
.function_arg_advance (args_so_far
, Pmode
, (tree
) 0, true);
3496 for (; count
< nargs
; count
++)
3498 rtx val
= va_arg (p
, rtx
);
3499 enum machine_mode mode
= (enum machine_mode
) va_arg (p
, int);
3502 /* We cannot convert the arg value to the mode the library wants here;
3503 must do it earlier where we know the signedness of the arg. */
3504 gcc_assert (mode
!= BLKmode
3505 && (GET_MODE (val
) == mode
|| GET_MODE (val
) == VOIDmode
));
3507 /* Make sure it is a reasonable operand for a move or push insn. */
3508 if (!REG_P (val
) && !MEM_P (val
)
3509 && !(CONSTANT_P (val
) && targetm
.legitimate_constant_p (mode
, val
)))
3510 val
= force_operand (val
, NULL_RTX
);
3512 if (pass_by_reference (&args_so_far_v
, mode
, NULL_TREE
, 1))
3516 = !reference_callee_copied (&args_so_far_v
, mode
, NULL_TREE
, 1);
3518 /* If this was a CONST function, it is now PURE since it now
3520 if (flags
& ECF_CONST
)
3522 flags
&= ~ECF_CONST
;
3526 if (MEM_P (val
) && !must_copy
)
3530 slot
= assign_temp (lang_hooks
.types
.type_for_mode (mode
, 0),
3532 emit_move_insn (slot
, val
);
3535 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3536 gen_rtx_USE (VOIDmode
, slot
),
3539 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3540 gen_rtx_CLOBBER (VOIDmode
,
3545 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3548 mode
= promote_function_mode (NULL_TREE
, mode
, &unsigned_p
, NULL_TREE
, 0);
3549 argvec
[count
].mode
= mode
;
3550 argvec
[count
].value
= convert_modes (mode
, GET_MODE (val
), val
, unsigned_p
);
3551 argvec
[count
].reg
= targetm
.calls
.function_arg (args_so_far
, mode
,
3554 argvec
[count
].partial
3555 = targetm
.calls
.arg_partial_bytes (args_so_far
, mode
, NULL_TREE
, 1);
3557 locate_and_pad_parm (mode
, NULL_TREE
,
3558 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3561 argvec
[count
].reg
!= 0,
3563 argvec
[count
].partial
,
3564 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3566 gcc_assert (!argvec
[count
].locate
.size
.var
);
3568 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3569 || reg_parm_stack_space
> 0)
3570 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3572 targetm
.calls
.function_arg_advance (args_so_far
, mode
, (tree
) 0, true);
3575 /* If this machine requires an external definition for library
3576 functions, write one out. */
3577 assemble_external_libcall (fun
);
3579 original_args_size
= args_size
;
3580 args_size
.constant
= (((args_size
.constant
3581 + stack_pointer_delta
3585 - stack_pointer_delta
);
3587 args_size
.constant
= MAX (args_size
.constant
,
3588 reg_parm_stack_space
);
3590 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3591 args_size
.constant
-= reg_parm_stack_space
;
3593 if (args_size
.constant
> crtl
->outgoing_args_size
)
3594 crtl
->outgoing_args_size
= args_size
.constant
;
3596 if (flag_stack_usage_info
&& !ACCUMULATE_OUTGOING_ARGS
)
3598 int pushed
= args_size
.constant
+ pending_stack_adjust
;
3599 if (pushed
> current_function_pushed_stack_size
)
3600 current_function_pushed_stack_size
= pushed
;
3603 if (ACCUMULATE_OUTGOING_ARGS
)
3605 /* Since the stack pointer will never be pushed, it is possible for
3606 the evaluation of a parm to clobber something we have already
3607 written to the stack. Since most function calls on RISC machines
3608 do not use the stack, this is uncommon, but must work correctly.
3610 Therefore, we save any area of the stack that was already written
3611 and that we are using. Here we set up to do this by making a new
3612 stack usage map from the old one.
3614 Another approach might be to try to reorder the argument
3615 evaluations to avoid this conflicting stack usage. */
3617 needed
= args_size
.constant
;
3619 /* Since we will be writing into the entire argument area, the
3620 map must be allocated for its entire size, not just the part that
3621 is the responsibility of the caller. */
3622 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3623 needed
+= reg_parm_stack_space
;
3625 #ifdef ARGS_GROW_DOWNWARD
3626 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3629 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3632 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
3633 stack_usage_map
= stack_usage_map_buf
;
3635 if (initial_highest_arg_in_use
)
3636 memcpy (stack_usage_map
, initial_stack_usage_map
,
3637 initial_highest_arg_in_use
);
3639 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3640 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3641 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3644 /* We must be careful to use virtual regs before they're instantiated,
3645 and real regs afterwards. Loop optimization, for example, can create
3646 new libcalls after we've instantiated the virtual regs, and if we
3647 use virtuals anyway, they won't match the rtl patterns. */
3649 if (virtuals_instantiated
)
3650 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3652 argblock
= virtual_outgoing_args_rtx
;
3657 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3660 /* If we push args individually in reverse order, perform stack alignment
3661 before the first push (the last arg). */
3662 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3663 anti_adjust_stack (GEN_INT (args_size
.constant
3664 - original_args_size
.constant
));
3666 if (PUSH_ARGS_REVERSED
)
3677 #ifdef REG_PARM_STACK_SPACE
3678 if (ACCUMULATE_OUTGOING_ARGS
)
3680 /* The argument list is the property of the called routine and it
3681 may clobber it. If the fixed area has been used for previous
3682 parameters, we must save and restore it. */
3683 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
3684 &low_to_save
, &high_to_save
);
3688 /* Push the args that need to be pushed. */
3690 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3691 are to be pushed. */
3692 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3694 enum machine_mode mode
= argvec
[argnum
].mode
;
3695 rtx val
= argvec
[argnum
].value
;
3696 rtx reg
= argvec
[argnum
].reg
;
3697 int partial
= argvec
[argnum
].partial
;
3698 unsigned int parm_align
= argvec
[argnum
].locate
.boundary
;
3699 int lower_bound
= 0, upper_bound
= 0, i
;
3701 if (! (reg
!= 0 && partial
== 0))
3705 if (ACCUMULATE_OUTGOING_ARGS
)
3707 /* If this is being stored into a pre-allocated, fixed-size,
3708 stack area, save any previous data at that location. */
3710 #ifdef ARGS_GROW_DOWNWARD
3711 /* stack_slot is negative, but we want to index stack_usage_map
3712 with positive values. */
3713 upper_bound
= -argvec
[argnum
].locate
.slot_offset
.constant
+ 1;
3714 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
3716 lower_bound
= argvec
[argnum
].locate
.slot_offset
.constant
;
3717 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
3721 /* Don't worry about things in the fixed argument area;
3722 it has already been saved. */
3723 if (i
< reg_parm_stack_space
)
3724 i
= reg_parm_stack_space
;
3725 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
3728 if (i
< upper_bound
)
3730 /* We need to make a save area. */
3732 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
3733 enum machine_mode save_mode
3734 = mode_for_size (size
, MODE_INT
, 1);
3736 = plus_constant (argblock
,
3737 argvec
[argnum
].locate
.offset
.constant
);
3739 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
3741 if (save_mode
== BLKmode
)
3743 argvec
[argnum
].save_area
3744 = assign_stack_temp (BLKmode
,
3745 argvec
[argnum
].locate
.size
.constant
,
3748 emit_block_move (validize_mem (argvec
[argnum
].save_area
),
3750 GEN_INT (argvec
[argnum
].locate
.size
.constant
),
3751 BLOCK_OP_CALL_PARM
);
3755 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3757 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3762 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, parm_align
,
3763 partial
, reg
, 0, argblock
,
3764 GEN_INT (argvec
[argnum
].locate
.offset
.constant
),
3765 reg_parm_stack_space
,
3766 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
));
3768 /* Now mark the segment we just used. */
3769 if (ACCUMULATE_OUTGOING_ARGS
)
3770 for (i
= lower_bound
; i
< upper_bound
; i
++)
3771 stack_usage_map
[i
] = 1;
3775 /* Indicate argument access so that alias.c knows that these
3778 use
= plus_constant (argblock
,
3779 argvec
[argnum
].locate
.offset
.constant
);
3781 /* When arguments are pushed, trying to tell alias.c where
3782 exactly this argument is won't work, because the
3783 auto-increment causes confusion. So we merely indicate
3784 that we access something with a known mode somewhere on
3786 use
= gen_rtx_PLUS (Pmode
, virtual_outgoing_args_rtx
,
3787 gen_rtx_SCRATCH (Pmode
));
3788 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
3789 use
= gen_rtx_USE (VOIDmode
, use
);
3790 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
3794 /* If we pushed args in forward order, perform stack alignment
3795 after pushing the last arg. */
3796 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3797 anti_adjust_stack (GEN_INT (args_size
.constant
3798 - original_args_size
.constant
));
3800 if (PUSH_ARGS_REVERSED
)
3805 fun
= prepare_call_address (NULL
, fun
, NULL
, &call_fusage
, 0, 0);
3807 /* Now load any reg parms into their regs. */
3809 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3810 are to be pushed. */
3811 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3813 enum machine_mode mode
= argvec
[argnum
].mode
;
3814 rtx val
= argvec
[argnum
].value
;
3815 rtx reg
= argvec
[argnum
].reg
;
3816 int partial
= argvec
[argnum
].partial
;
3818 /* Handle calls that pass values in multiple non-contiguous
3819 locations. The PA64 has examples of this for library calls. */
3820 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3821 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
3822 else if (reg
!= 0 && partial
== 0)
3823 emit_move_insn (reg
, val
);
3828 /* Any regs containing parms remain in use through the call. */
3829 for (count
= 0; count
< nargs
; count
++)
3831 rtx reg
= argvec
[count
].reg
;
3832 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3833 use_group_regs (&call_fusage
, reg
);
3836 int partial
= argvec
[count
].partial
;
3840 gcc_assert (partial
% UNITS_PER_WORD
== 0);
3841 nregs
= partial
/ UNITS_PER_WORD
;
3842 use_regs (&call_fusage
, REGNO (reg
), nregs
);
3845 use_reg (&call_fusage
, reg
);
3849 /* Pass the function the address in which to return a structure value. */
3850 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
3852 emit_move_insn (struct_value
,
3854 force_operand (XEXP (mem_value
, 0),
3856 if (REG_P (struct_value
))
3857 use_reg (&call_fusage
, struct_value
);
3860 /* Don't allow popping to be deferred, since then
3861 cse'ing of library calls could delete a call and leave the pop. */
3863 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
3864 ? hard_libcall_value (outmode
, orgfun
) : NULL_RTX
);
3866 /* Stack must be properly aligned now. */
3867 gcc_assert (!(stack_pointer_delta
3868 & (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1)));
3870 before_call
= get_last_insn ();
3872 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3873 will set inhibit_defer_pop to that value. */
3874 /* The return type is needed to decide how many bytes the function pops.
3875 Signedness plays no role in that, so for simplicity, we pretend it's
3876 always signed. We also assume that the list of arguments passed has
3877 no impact, so we pretend it is unknown. */
3879 emit_call_1 (fun
, NULL
,
3880 get_identifier (XSTR (orgfun
, 0)),
3881 build_function_type (tfom
, NULL_TREE
),
3882 original_args_size
.constant
, args_size
.constant
,
3884 targetm
.calls
.function_arg (args_so_far
,
3885 VOIDmode
, void_type_node
, true),
3887 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, args_so_far
);
3889 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
3890 that it should complain if nonvolatile values are live. For
3891 functions that cannot return, inform flow that control does not
3894 if (flags
& ECF_NORETURN
)
3896 /* The barrier note must be emitted
3897 immediately after the CALL_INSN. Some ports emit more than
3898 just a CALL_INSN above, so we must search for it here. */
3900 rtx last
= get_last_insn ();
3901 while (!CALL_P (last
))
3903 last
= PREV_INSN (last
);
3904 /* There was no CALL_INSN? */
3905 gcc_assert (last
!= before_call
);
3908 emit_barrier_after (last
);
3911 /* Now restore inhibit_defer_pop to its actual original value. */
3916 /* Copy the value to the right place. */
3917 if (outmode
!= VOIDmode
&& retval
)
3923 if (value
!= mem_value
)
3924 emit_move_insn (value
, mem_value
);
3926 else if (GET_CODE (valreg
) == PARALLEL
)
3929 value
= gen_reg_rtx (outmode
);
3930 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
3934 /* Convert to the proper mode if a promotion has been active. */
3935 if (GET_MODE (valreg
) != outmode
)
3937 int unsignedp
= TYPE_UNSIGNED (tfom
);
3939 gcc_assert (promote_function_mode (tfom
, outmode
, &unsignedp
,
3940 fndecl
? TREE_TYPE (fndecl
) : fntype
, 1)
3941 == GET_MODE (valreg
));
3942 valreg
= convert_modes (outmode
, GET_MODE (valreg
), valreg
, 0);
3946 emit_move_insn (value
, valreg
);
3952 if (ACCUMULATE_OUTGOING_ARGS
)
3954 #ifdef REG_PARM_STACK_SPACE
3956 restore_fixed_argument_area (save_area
, argblock
,
3957 high_to_save
, low_to_save
);
3960 /* If we saved any argument areas, restore them. */
3961 for (count
= 0; count
< nargs
; count
++)
3962 if (argvec
[count
].save_area
)
3964 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
3965 rtx adr
= plus_constant (argblock
,
3966 argvec
[count
].locate
.offset
.constant
);
3967 rtx stack_area
= gen_rtx_MEM (save_mode
,
3968 memory_address (save_mode
, adr
));
3970 if (save_mode
== BLKmode
)
3971 emit_block_move (stack_area
,
3972 validize_mem (argvec
[count
].save_area
),
3973 GEN_INT (argvec
[count
].locate
.size
.constant
),
3974 BLOCK_OP_CALL_PARM
);
3976 emit_move_insn (stack_area
, argvec
[count
].save_area
);
3979 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3980 stack_usage_map
= initial_stack_usage_map
;
3983 free (stack_usage_map_buf
);
3989 /* Output a library call to function FUN (a SYMBOL_REF rtx)
3990 (emitting the queue unless NO_QUEUE is nonzero),
3991 for a value of mode OUTMODE,
3992 with NARGS different arguments, passed as alternating rtx values
3993 and machine_modes to convert them to.
3995 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
3996 `const' calls, LCT_PURE for `pure' calls, or other LCT_ value for
3997 other types of library calls. */
4000 emit_library_call (rtx orgfun
, enum libcall_type fn_type
,
4001 enum machine_mode outmode
, int nargs
, ...)
4005 va_start (p
, nargs
);
4006 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
4010 /* Like emit_library_call except that an extra argument, VALUE,
4011 comes second and says where to store the result.
4012 (If VALUE is zero, this function chooses a convenient way
4013 to return the value.
4015 This function returns an rtx for where the value is to be found.
4016 If VALUE is nonzero, VALUE is returned. */
4019 emit_library_call_value (rtx orgfun
, rtx value
,
4020 enum libcall_type fn_type
,
4021 enum machine_mode outmode
, int nargs
, ...)
4026 va_start (p
, nargs
);
4027 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
4034 /* Store a single argument for a function call
4035 into the register or memory area where it must be passed.
4036 *ARG describes the argument value and where to pass it.
4038 ARGBLOCK is the address of the stack-block for all the arguments,
4039 or 0 on a machine where arguments are pushed individually.
4041 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4042 so must be careful about how the stack is used.
4044 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4045 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4046 that we need not worry about saving and restoring the stack.
4048 FNDECL is the declaration of the function we are calling.
4050 Return nonzero if this arg should cause sibcall failure,
4054 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
4055 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
4057 tree pval
= arg
->tree_value
;
4061 int i
, lower_bound
= 0, upper_bound
= 0;
4062 int sibcall_failure
= 0;
4064 if (TREE_CODE (pval
) == ERROR_MARK
)
4067 /* Push a new temporary level for any temporaries we make for
4071 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4073 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4074 save any previous data at that location. */
4075 if (argblock
&& ! variable_size
&& arg
->stack
)
4077 #ifdef ARGS_GROW_DOWNWARD
4078 /* stack_slot is negative, but we want to index stack_usage_map
4079 with positive values. */
4080 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4081 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4085 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
4087 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4088 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4092 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
4096 /* Don't worry about things in the fixed argument area;
4097 it has already been saved. */
4098 if (i
< reg_parm_stack_space
)
4099 i
= reg_parm_stack_space
;
4100 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
4103 if (i
< upper_bound
)
4105 /* We need to make a save area. */
4106 unsigned int size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
4107 enum machine_mode save_mode
= mode_for_size (size
, MODE_INT
, 1);
4108 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
4109 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
4111 if (save_mode
== BLKmode
)
4113 tree ot
= TREE_TYPE (arg
->tree_value
);
4114 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4115 | TYPE_QUAL_CONST
));
4117 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4118 preserve_temp_slots (arg
->save_area
);
4119 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4120 GEN_INT (arg
->locate
.size
.constant
),
4121 BLOCK_OP_CALL_PARM
);
4125 arg
->save_area
= gen_reg_rtx (save_mode
);
4126 emit_move_insn (arg
->save_area
, stack_area
);
4132 /* If this isn't going to be placed on both the stack and in registers,
4133 set up the register and number of words. */
4134 if (! arg
->pass_on_stack
)
4136 if (flags
& ECF_SIBCALL
)
4137 reg
= arg
->tail_call_reg
;
4140 partial
= arg
->partial
;
4143 /* Being passed entirely in a register. We shouldn't be called in
4145 gcc_assert (reg
== 0 || partial
!= 0);
4147 /* If this arg needs special alignment, don't load the registers
4149 if (arg
->n_aligned_regs
!= 0)
4152 /* If this is being passed partially in a register, we can't evaluate
4153 it directly into its stack slot. Otherwise, we can. */
4154 if (arg
->value
== 0)
4156 /* stack_arg_under_construction is nonzero if a function argument is
4157 being evaluated directly into the outgoing argument list and
4158 expand_call must take special action to preserve the argument list
4159 if it is called recursively.
4161 For scalar function arguments stack_usage_map is sufficient to
4162 determine which stack slots must be saved and restored. Scalar
4163 arguments in general have pass_on_stack == 0.
4165 If this argument is initialized by a function which takes the
4166 address of the argument (a C++ constructor or a C function
4167 returning a BLKmode structure), then stack_usage_map is
4168 insufficient and expand_call must push the stack around the
4169 function call. Such arguments have pass_on_stack == 1.
4171 Note that it is always safe to set stack_arg_under_construction,
4172 but this generates suboptimal code if set when not needed. */
4174 if (arg
->pass_on_stack
)
4175 stack_arg_under_construction
++;
4177 arg
->value
= expand_expr (pval
,
4179 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4180 ? NULL_RTX
: arg
->stack
,
4181 VOIDmode
, EXPAND_STACK_PARM
);
4183 /* If we are promoting object (or for any other reason) the mode
4184 doesn't agree, convert the mode. */
4186 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4187 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4188 arg
->value
, arg
->unsignedp
);
4190 if (arg
->pass_on_stack
)
4191 stack_arg_under_construction
--;
4194 /* Check for overlap with already clobbered argument area. */
4195 if ((flags
& ECF_SIBCALL
)
4196 && MEM_P (arg
->value
)
4197 && mem_overlaps_already_clobbered_arg_p (XEXP (arg
->value
, 0),
4198 arg
->locate
.size
.constant
))
4199 sibcall_failure
= 1;
4201 /* Don't allow anything left on stack from computation
4202 of argument to alloca. */
4203 if (flags
& ECF_MAY_BE_ALLOCA
)
4204 do_pending_stack_adjust ();
4206 if (arg
->value
== arg
->stack
)
4207 /* If the value is already in the stack slot, we are done. */
4209 else if (arg
->mode
!= BLKmode
)
4212 unsigned int parm_align
;
4214 /* Argument is a scalar, not entirely passed in registers.
4215 (If part is passed in registers, arg->partial says how much
4216 and emit_push_insn will take care of putting it there.)
4218 Push it, and if its size is less than the
4219 amount of space allocated to it,
4220 also bump stack pointer by the additional space.
4221 Note that in C the default argument promotions
4222 will prevent such mismatches. */
4224 size
= GET_MODE_SIZE (arg
->mode
);
4225 /* Compute how much space the push instruction will push.
4226 On many machines, pushing a byte will advance the stack
4227 pointer by a halfword. */
4228 #ifdef PUSH_ROUNDING
4229 size
= PUSH_ROUNDING (size
);
4233 /* Compute how much space the argument should get:
4234 round up to a multiple of the alignment for arguments. */
4235 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4236 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4237 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4238 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4240 /* Compute the alignment of the pushed argument. */
4241 parm_align
= arg
->locate
.boundary
;
4242 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4244 int pad
= used
- size
;
4247 unsigned int pad_align
= (pad
& -pad
) * BITS_PER_UNIT
;
4248 parm_align
= MIN (parm_align
, pad_align
);
4252 /* This isn't already where we want it on the stack, so put it there.
4253 This can either be done with push or copy insns. */
4254 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
,
4255 parm_align
, partial
, reg
, used
- size
, argblock
,
4256 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4257 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4259 /* Unless this is a partially-in-register argument, the argument is now
4262 arg
->value
= arg
->stack
;
4266 /* BLKmode, at least partly to be pushed. */
4268 unsigned int parm_align
;
4272 /* Pushing a nonscalar.
4273 If part is passed in registers, PARTIAL says how much
4274 and emit_push_insn will take care of putting it there. */
4276 /* Round its size up to a multiple
4277 of the allocation unit for arguments. */
4279 if (arg
->locate
.size
.var
!= 0)
4282 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
4286 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4287 for BLKmode is careful to avoid it. */
4288 excess
= (arg
->locate
.size
.constant
4289 - int_size_in_bytes (TREE_TYPE (pval
))
4291 size_rtx
= expand_expr (size_in_bytes (TREE_TYPE (pval
)),
4292 NULL_RTX
, TYPE_MODE (sizetype
),
4296 parm_align
= arg
->locate
.boundary
;
4298 /* When an argument is padded down, the block is aligned to
4299 PARM_BOUNDARY, but the actual argument isn't. */
4300 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4302 if (arg
->locate
.size
.var
)
4303 parm_align
= BITS_PER_UNIT
;
4306 unsigned int excess_align
= (excess
& -excess
) * BITS_PER_UNIT
;
4307 parm_align
= MIN (parm_align
, excess_align
);
4311 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
4313 /* emit_push_insn might not work properly if arg->value and
4314 argblock + arg->locate.offset areas overlap. */
4318 if (XEXP (x
, 0) == crtl
->args
.internal_arg_pointer
4319 || (GET_CODE (XEXP (x
, 0)) == PLUS
4320 && XEXP (XEXP (x
, 0), 0) ==
4321 crtl
->args
.internal_arg_pointer
4322 && CONST_INT_P (XEXP (XEXP (x
, 0), 1))))
4324 if (XEXP (x
, 0) != crtl
->args
.internal_arg_pointer
)
4325 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4327 /* expand_call should ensure this. */
4328 gcc_assert (!arg
->locate
.offset
.var
4329 && arg
->locate
.size
.var
== 0
4330 && CONST_INT_P (size_rtx
));
4332 if (arg
->locate
.offset
.constant
> i
)
4334 if (arg
->locate
.offset
.constant
< i
+ INTVAL (size_rtx
))
4335 sibcall_failure
= 1;
4337 else if (arg
->locate
.offset
.constant
< i
)
4339 /* Use arg->locate.size.constant instead of size_rtx
4340 because we only care about the part of the argument
4342 if (i
< (arg
->locate
.offset
.constant
4343 + arg
->locate
.size
.constant
))
4344 sibcall_failure
= 1;
4348 /* Even though they appear to be at the same location,
4349 if part of the outgoing argument is in registers,
4350 they aren't really at the same location. Check for
4351 this by making sure that the incoming size is the
4352 same as the outgoing size. */
4353 if (arg
->locate
.size
.constant
!= INTVAL (size_rtx
))
4354 sibcall_failure
= 1;
4359 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4360 parm_align
, partial
, reg
, excess
, argblock
,
4361 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4362 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4364 /* Unless this is a partially-in-register argument, the argument is now
4367 ??? Unlike the case above, in which we want the actual
4368 address of the data, so that we can load it directly into a
4369 register, here we want the address of the stack slot, so that
4370 it's properly aligned for word-by-word copying or something
4371 like that. It's not clear that this is always correct. */
4373 arg
->value
= arg
->stack_slot
;
4376 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
4378 tree type
= TREE_TYPE (arg
->tree_value
);
4380 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
4381 int_size_in_bytes (type
));
4384 /* Mark all slots this store used. */
4385 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
4386 && argblock
&& ! variable_size
&& arg
->stack
)
4387 for (i
= lower_bound
; i
< upper_bound
; i
++)
4388 stack_usage_map
[i
] = 1;
4390 /* Once we have pushed something, pops can't safely
4391 be deferred during the rest of the arguments. */
4394 /* Free any temporary slots made in processing this argument. Show
4395 that we might have taken the address of something and pushed that
4397 preserve_temp_slots (NULL_RTX
);
4401 return sibcall_failure
;
4404 /* Nonzero if we do not know how to pass TYPE solely in registers. */
4407 must_pass_in_stack_var_size (enum machine_mode mode ATTRIBUTE_UNUSED
,
4413 /* If the type has variable size... */
4414 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4417 /* If the type is marked as addressable (it is required
4418 to be constructed into the stack)... */
4419 if (TREE_ADDRESSABLE (type
))
4425 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
4426 takes trailing padding of a structure into account. */
4427 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
4430 must_pass_in_stack_var_size_or_pad (enum machine_mode mode
, const_tree type
)
4435 /* If the type has variable size... */
4436 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4439 /* If the type is marked as addressable (it is required
4440 to be constructed into the stack)... */
4441 if (TREE_ADDRESSABLE (type
))
4444 /* If the padding and mode of the type is such that a copy into
4445 a register would put it into the wrong part of the register. */
4447 && int_size_in_bytes (type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
4448 && (FUNCTION_ARG_PADDING (mode
, type
)
4449 == (BYTES_BIG_ENDIAN
? upward
: downward
)))