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 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"
46 #include "tree-flow.h"
48 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
49 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
51 /* Data structure and subroutines used within expand_call. */
55 /* Tree node for this argument. */
57 /* Mode for value; TYPE_MODE unless promoted. */
58 enum machine_mode mode
;
59 /* Current RTL value for argument, or 0 if it isn't precomputed. */
61 /* Initially-compute RTL value for argument; only for const functions. */
63 /* Register to pass this argument in, 0 if passed on stack, or an
64 PARALLEL if the arg is to be copied into multiple non-contiguous
67 /* Register to pass this argument in when generating tail call sequence.
68 This is not the same register as for normal calls on machines with
71 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
72 form for emit_group_move. */
74 /* If REG was promoted from the actual mode of the argument expression,
75 indicates whether the promotion is sign- or zero-extended. */
77 /* Number of bytes to put in registers. 0 means put the whole arg
78 in registers. Also 0 if not passed in registers. */
80 /* Nonzero if argument must be passed on stack.
81 Note that some arguments may be passed on the stack
82 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
83 pass_on_stack identifies arguments that *cannot* go in registers. */
85 /* Some fields packaged up for locate_and_pad_parm. */
86 struct locate_and_pad_arg_data locate
;
87 /* Location on the stack at which parameter should be stored. The store
88 has already been done if STACK == VALUE. */
90 /* Location on the stack of the start of this argument slot. This can
91 differ from STACK if this arg pads downward. This location is known
92 to be aligned to FUNCTION_ARG_BOUNDARY. */
94 /* Place that this stack area has been saved, if needed. */
96 /* If an argument's alignment does not permit direct copying into registers,
97 copy in smaller-sized pieces into pseudos. These are stored in a
98 block pointed to by this field. The next field says how many
99 word-sized pseudos we made. */
104 /* A vector of one char per byte of stack space. A byte if nonzero if
105 the corresponding stack location has been used.
106 This vector is used to prevent a function call within an argument from
107 clobbering any stack already set up. */
108 static char *stack_usage_map
;
110 /* Size of STACK_USAGE_MAP. */
111 static int highest_outgoing_arg_in_use
;
113 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
114 stack location's tail call argument has been already stored into the stack.
115 This bitmap is used to prevent sibling call optimization if function tries
116 to use parent's incoming argument slots when they have been already
117 overwritten with tail call arguments. */
118 static sbitmap stored_args_map
;
120 /* stack_arg_under_construction is nonzero when an argument may be
121 initialized with a constructor call (including a C function that
122 returns a BLKmode struct) and expand_call must take special action
123 to make sure the object being constructed does not overlap the
124 argument list for the constructor call. */
125 static int stack_arg_under_construction
;
127 static void emit_call_1 (rtx
, tree
, tree
, tree
, HOST_WIDE_INT
, HOST_WIDE_INT
,
128 HOST_WIDE_INT
, rtx
, rtx
, int, rtx
, int,
130 static void precompute_register_parameters (int, struct arg_data
*, int *);
131 static int store_one_arg (struct arg_data
*, rtx
, int, int, int);
132 static void store_unaligned_arguments_into_pseudos (struct arg_data
*, int);
133 static int finalize_must_preallocate (int, int, struct arg_data
*,
135 static void precompute_arguments (int, struct arg_data
*);
136 static int compute_argument_block_size (int, struct args_size
*, tree
, tree
, int);
137 static void initialize_argument_information (int, struct arg_data
*,
138 struct args_size
*, int,
140 tree
, tree
, CUMULATIVE_ARGS
*, int,
141 rtx
*, int *, int *, int *,
143 static void compute_argument_addresses (struct arg_data
*, rtx
, int);
144 static rtx
rtx_for_function_call (tree
, tree
);
145 static void load_register_parameters (struct arg_data
*, int, rtx
*, int,
147 static rtx
emit_library_call_value_1 (int, rtx
, rtx
, enum libcall_type
,
148 enum machine_mode
, int, va_list);
149 static int special_function_p (const_tree
, int);
150 static int check_sibcall_argument_overlap_1 (rtx
);
151 static int check_sibcall_argument_overlap (rtx
, struct arg_data
*, int);
153 static int combine_pending_stack_adjustment_and_call (int, struct args_size
*,
155 static tree
split_complex_types (tree
);
157 #ifdef REG_PARM_STACK_SPACE
158 static rtx
save_fixed_argument_area (int, rtx
, int *, int *);
159 static void restore_fixed_argument_area (rtx
, rtx
, int, int);
162 /* Force FUNEXP into a form suitable for the address of a CALL,
163 and return that as an rtx. Also load the static chain register
164 if FNDECL is a nested function.
166 CALL_FUSAGE points to a variable holding the prospective
167 CALL_INSN_FUNCTION_USAGE information. */
170 prepare_call_address (tree fndecl
, rtx funexp
, rtx static_chain_value
,
171 rtx
*call_fusage
, int reg_parm_seen
, int sibcallp
)
173 /* Make a valid memory address and copy constants through pseudo-regs,
174 but not for a constant address if -fno-function-cse. */
175 if (GET_CODE (funexp
) != SYMBOL_REF
)
176 /* If we are using registers for parameters, force the
177 function address into a register now. */
178 funexp
= ((reg_parm_seen
179 && targetm
.small_register_classes_for_mode_p (FUNCTION_MODE
))
180 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
181 : memory_address (FUNCTION_MODE
, funexp
));
184 #ifndef NO_FUNCTION_CSE
185 if (optimize
&& ! flag_no_function_cse
)
186 funexp
= force_reg (Pmode
, funexp
);
190 if (static_chain_value
!= 0)
195 chain
= targetm
.calls
.static_chain (fndecl
, false);
196 static_chain_value
= convert_memory_address (Pmode
, static_chain_value
);
198 emit_move_insn (chain
, static_chain_value
);
200 use_reg (call_fusage
, chain
);
206 /* Generate instructions to call function FUNEXP,
207 and optionally pop the results.
208 The CALL_INSN is the first insn generated.
210 FNDECL is the declaration node of the function. This is given to the
211 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
214 FUNTYPE is the data type of the function. This is given to the hook
215 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
216 own args. We used to allow an identifier for library functions, but
217 that doesn't work when the return type is an aggregate type and the
218 calling convention says that the pointer to this aggregate is to be
219 popped by the callee.
221 STACK_SIZE is the number of bytes of arguments on the stack,
222 ROUNDED_STACK_SIZE is that number rounded up to
223 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
224 both to put into the call insn and to generate explicit popping
227 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
228 It is zero if this call doesn't want a structure value.
230 NEXT_ARG_REG is the rtx that results from executing
231 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
232 just after all the args have had their registers assigned.
233 This could be whatever you like, but normally it is the first
234 arg-register beyond those used for args in this call,
235 or 0 if all the arg-registers are used in this call.
236 It is passed on to `gen_call' so you can put this info in the call insn.
238 VALREG is a hard register in which a value is returned,
239 or 0 if the call does not return a value.
241 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
242 the args to this call were processed.
243 We restore `inhibit_defer_pop' to that value.
245 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
246 denote registers used by the called function. */
249 emit_call_1 (rtx funexp
, tree fntree ATTRIBUTE_UNUSED
, tree fndecl ATTRIBUTE_UNUSED
,
250 tree funtype ATTRIBUTE_UNUSED
,
251 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED
,
252 HOST_WIDE_INT rounded_stack_size
,
253 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED
,
254 rtx next_arg_reg ATTRIBUTE_UNUSED
, rtx valreg
,
255 int old_inhibit_defer_pop
, rtx call_fusage
, int ecf_flags
,
256 CUMULATIVE_ARGS
*args_so_far ATTRIBUTE_UNUSED
)
258 rtx rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
260 int already_popped
= 0;
261 HOST_WIDE_INT n_popped
262 = targetm
.calls
.return_pops_args (fndecl
, funtype
, stack_size
);
264 #ifdef CALL_POPS_ARGS
265 n_popped
+= CALL_POPS_ARGS (* args_so_far
);
268 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
269 and we don't want to load it into a register as an optimization,
270 because prepare_call_address already did it if it should be done. */
271 if (GET_CODE (funexp
) != SYMBOL_REF
)
272 funexp
= memory_address (FUNCTION_MODE
, funexp
);
274 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
275 if ((ecf_flags
& ECF_SIBCALL
)
276 && HAVE_sibcall_pop
&& HAVE_sibcall_value_pop
277 && (n_popped
> 0 || stack_size
== 0))
279 rtx n_pop
= GEN_INT (n_popped
);
282 /* If this subroutine pops its own args, record that in the call insn
283 if possible, for the sake of frame pointer elimination. */
286 pat
= GEN_SIBCALL_VALUE_POP (valreg
,
287 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
288 rounded_stack_size_rtx
, next_arg_reg
,
291 pat
= GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
292 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
294 emit_call_insn (pat
);
300 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
301 /* If the target has "call" or "call_value" insns, then prefer them
302 if no arguments are actually popped. If the target does not have
303 "call" or "call_value" insns, then we must use the popping versions
304 even if the call has no arguments to pop. */
305 #if defined (HAVE_call) && defined (HAVE_call_value)
306 if (HAVE_call
&& HAVE_call_value
&& HAVE_call_pop
&& HAVE_call_value_pop
309 if (HAVE_call_pop
&& HAVE_call_value_pop
)
312 rtx n_pop
= GEN_INT (n_popped
);
315 /* If this subroutine pops its own args, record that in the call insn
316 if possible, for the sake of frame pointer elimination. */
319 pat
= GEN_CALL_VALUE_POP (valreg
,
320 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
321 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
323 pat
= GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
324 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
326 emit_call_insn (pat
);
332 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
333 if ((ecf_flags
& ECF_SIBCALL
)
334 && HAVE_sibcall
&& HAVE_sibcall_value
)
337 emit_call_insn (GEN_SIBCALL_VALUE (valreg
,
338 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
339 rounded_stack_size_rtx
,
340 next_arg_reg
, NULL_RTX
));
342 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
343 rounded_stack_size_rtx
, next_arg_reg
,
344 GEN_INT (struct_value_size
)));
349 #if defined (HAVE_call) && defined (HAVE_call_value)
350 if (HAVE_call
&& HAVE_call_value
)
353 emit_call_insn (GEN_CALL_VALUE (valreg
,
354 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
355 rounded_stack_size_rtx
, next_arg_reg
,
358 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
359 rounded_stack_size_rtx
, next_arg_reg
,
360 GEN_INT (struct_value_size
)));
366 /* Find the call we just emitted. */
367 call_insn
= last_call_insn ();
369 /* Put the register usage information there. */
370 add_function_usage_to (call_insn
, call_fusage
);
372 /* If this is a const call, then set the insn's unchanging bit. */
373 if (ecf_flags
& ECF_CONST
)
374 RTL_CONST_CALL_P (call_insn
) = 1;
376 /* If this is a pure call, then set the insn's unchanging bit. */
377 if (ecf_flags
& ECF_PURE
)
378 RTL_PURE_CALL_P (call_insn
) = 1;
380 /* If this is a const call, then set the insn's unchanging bit. */
381 if (ecf_flags
& ECF_LOOPING_CONST_OR_PURE
)
382 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn
) = 1;
384 /* Create a nothrow REG_EH_REGION note, if needed. */
385 make_reg_eh_region_note (call_insn
, ecf_flags
, 0);
387 if (ecf_flags
& ECF_NORETURN
)
388 add_reg_note (call_insn
, REG_NORETURN
, const0_rtx
);
390 if (ecf_flags
& ECF_RETURNS_TWICE
)
392 add_reg_note (call_insn
, REG_SETJMP
, const0_rtx
);
393 cfun
->calls_setjmp
= 1;
396 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
398 /* Record debug information for virtual calls. */
399 if (flag_enable_icf_debug
&& fndecl
== NULL
)
400 (*debug_hooks
->virtual_call_token
) (CALL_EXPR_FN (fntree
),
401 INSN_UID (call_insn
));
403 /* Restore this now, so that we do defer pops for this call's args
404 if the context of the call as a whole permits. */
405 inhibit_defer_pop
= old_inhibit_defer_pop
;
410 CALL_INSN_FUNCTION_USAGE (call_insn
)
411 = gen_rtx_EXPR_LIST (VOIDmode
,
412 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
413 CALL_INSN_FUNCTION_USAGE (call_insn
));
414 rounded_stack_size
-= n_popped
;
415 rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
416 stack_pointer_delta
-= n_popped
;
418 /* If popup is needed, stack realign must use DRAP */
419 if (SUPPORTS_STACK_ALIGNMENT
)
420 crtl
->need_drap
= true;
423 if (!ACCUMULATE_OUTGOING_ARGS
)
425 /* If returning from the subroutine does not automatically pop the args,
426 we need an instruction to pop them sooner or later.
427 Perhaps do it now; perhaps just record how much space to pop later.
429 If returning from the subroutine does pop the args, indicate that the
430 stack pointer will be changed. */
432 if (rounded_stack_size
!= 0)
434 if (ecf_flags
& ECF_NORETURN
)
435 /* Just pretend we did the pop. */
436 stack_pointer_delta
-= rounded_stack_size
;
437 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
438 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
439 pending_stack_adjust
+= rounded_stack_size
;
441 adjust_stack (rounded_stack_size_rtx
);
444 /* When we accumulate outgoing args, we must avoid any stack manipulations.
445 Restore the stack pointer to its original value now. Usually
446 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
447 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
448 popping variants of functions exist as well.
450 ??? We may optimize similar to defer_pop above, but it is
451 probably not worthwhile.
453 ??? It will be worthwhile to enable combine_stack_adjustments even for
456 anti_adjust_stack (GEN_INT (n_popped
));
459 /* Determine if the function identified by NAME and FNDECL is one with
460 special properties we wish to know about.
462 For example, if the function might return more than one time (setjmp), then
463 set RETURNS_TWICE to a nonzero value.
465 Similarly set NORETURN if the function is in the longjmp family.
467 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
468 space from the stack such as alloca. */
471 special_function_p (const_tree fndecl
, int flags
)
473 if (fndecl
&& DECL_NAME (fndecl
)
474 && IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) <= 17
475 /* Exclude functions not at the file scope, or not `extern',
476 since they are not the magic functions we would otherwise
478 FIXME: this should be handled with attributes, not with this
479 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
480 because you can declare fork() inside a function if you
482 && (DECL_CONTEXT (fndecl
) == NULL_TREE
483 || TREE_CODE (DECL_CONTEXT (fndecl
)) == TRANSLATION_UNIT_DECL
)
484 && TREE_PUBLIC (fndecl
))
486 const char *name
= IDENTIFIER_POINTER (DECL_NAME (fndecl
));
487 const char *tname
= name
;
489 /* We assume that alloca will always be called by name. It
490 makes no sense to pass it as a pointer-to-function to
491 anything that does not understand its behavior. */
492 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 6
494 && ! strcmp (name
, "alloca"))
495 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 16
497 && ! strcmp (name
, "__builtin_alloca"))))
498 flags
|= ECF_MAY_BE_ALLOCA
;
500 /* Disregard prefix _, __, __x or __builtin_. */
505 && !strncmp (name
+ 3, "uiltin_", 7))
507 else if (name
[1] == '_' && name
[2] == 'x')
509 else if (name
[1] == '_')
518 && (! strcmp (tname
, "setjmp")
519 || ! strcmp (tname
, "setjmp_syscall")))
521 && ! strcmp (tname
, "sigsetjmp"))
523 && ! strcmp (tname
, "savectx")))
524 flags
|= ECF_RETURNS_TWICE
;
527 && ! strcmp (tname
, "siglongjmp"))
528 flags
|= ECF_NORETURN
;
530 else if ((tname
[0] == 'q' && tname
[1] == 's'
531 && ! strcmp (tname
, "qsetjmp"))
532 || (tname
[0] == 'v' && tname
[1] == 'f'
533 && ! strcmp (tname
, "vfork"))
534 || (tname
[0] == 'g' && tname
[1] == 'e'
535 && !strcmp (tname
, "getcontext")))
536 flags
|= ECF_RETURNS_TWICE
;
538 else if (tname
[0] == 'l' && tname
[1] == 'o'
539 && ! strcmp (tname
, "longjmp"))
540 flags
|= ECF_NORETURN
;
546 /* Return nonzero when FNDECL represents a call to setjmp. */
549 setjmp_call_p (const_tree fndecl
)
551 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
555 /* Return true if STMT is an alloca call. */
558 gimple_alloca_call_p (const_gimple stmt
)
562 if (!is_gimple_call (stmt
))
565 fndecl
= gimple_call_fndecl (stmt
);
566 if (fndecl
&& (special_function_p (fndecl
, 0) & ECF_MAY_BE_ALLOCA
))
572 /* Return true when exp contains alloca call. */
575 alloca_call_p (const_tree exp
)
577 if (TREE_CODE (exp
) == CALL_EXPR
578 && TREE_CODE (CALL_EXPR_FN (exp
)) == ADDR_EXPR
579 && (TREE_CODE (TREE_OPERAND (CALL_EXPR_FN (exp
), 0)) == FUNCTION_DECL
)
580 && (special_function_p (TREE_OPERAND (CALL_EXPR_FN (exp
), 0), 0)
581 & ECF_MAY_BE_ALLOCA
))
586 /* Detect flags (function attributes) from the function decl or type node. */
589 flags_from_decl_or_type (const_tree exp
)
595 /* The function exp may have the `malloc' attribute. */
596 if (DECL_IS_MALLOC (exp
))
599 /* The function exp may have the `returns_twice' attribute. */
600 if (DECL_IS_RETURNS_TWICE (exp
))
601 flags
|= ECF_RETURNS_TWICE
;
603 /* Process the pure and const attributes. */
604 if (TREE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
606 if (DECL_PURE_P (exp
))
608 if (DECL_LOOPING_CONST_OR_PURE_P (exp
))
609 flags
|= ECF_LOOPING_CONST_OR_PURE
;
611 if (DECL_IS_NOVOPS (exp
))
614 if (TREE_NOTHROW (exp
))
615 flags
|= ECF_NOTHROW
;
617 flags
= special_function_p (exp
, flags
);
619 else if (TYPE_P (exp
) && TYPE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
622 if (TREE_THIS_VOLATILE (exp
))
623 flags
|= ECF_NORETURN
;
628 /* Detect flags from a CALL_EXPR. */
631 call_expr_flags (const_tree t
)
634 tree decl
= get_callee_fndecl (t
);
637 flags
= flags_from_decl_or_type (decl
);
640 t
= TREE_TYPE (CALL_EXPR_FN (t
));
641 if (t
&& TREE_CODE (t
) == POINTER_TYPE
)
642 flags
= flags_from_decl_or_type (TREE_TYPE (t
));
650 /* Precompute all register parameters as described by ARGS, storing values
651 into fields within the ARGS array.
653 NUM_ACTUALS indicates the total number elements in the ARGS array.
655 Set REG_PARM_SEEN if we encounter a register parameter. */
658 precompute_register_parameters (int num_actuals
, struct arg_data
*args
,
665 for (i
= 0; i
< num_actuals
; i
++)
666 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
670 if (args
[i
].value
== 0)
673 args
[i
].value
= expand_normal (args
[i
].tree_value
);
674 preserve_temp_slots (args
[i
].value
);
678 /* If the value is a non-legitimate constant, force it into a
679 pseudo now. TLS symbols sometimes need a call to resolve. */
680 if (CONSTANT_P (args
[i
].value
)
681 && !LEGITIMATE_CONSTANT_P (args
[i
].value
))
682 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
684 /* If we are to promote the function arg to a wider mode,
687 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
689 = convert_modes (args
[i
].mode
,
690 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
691 args
[i
].value
, args
[i
].unsignedp
);
693 /* If we're going to have to load the value by parts, pull the
694 parts into pseudos. The part extraction process can involve
695 non-trivial computation. */
696 if (GET_CODE (args
[i
].reg
) == PARALLEL
)
698 tree type
= TREE_TYPE (args
[i
].tree_value
);
699 args
[i
].parallel_value
700 = emit_group_load_into_temps (args
[i
].reg
, args
[i
].value
,
701 type
, int_size_in_bytes (type
));
704 /* If the value is expensive, and we are inside an appropriately
705 short loop, put the value into a pseudo and then put the pseudo
708 For small register classes, also do this if this call uses
709 register parameters. This is to avoid reload conflicts while
710 loading the parameters registers. */
712 else if ((! (REG_P (args
[i
].value
)
713 || (GET_CODE (args
[i
].value
) == SUBREG
714 && REG_P (SUBREG_REG (args
[i
].value
)))))
715 && args
[i
].mode
!= BLKmode
716 && rtx_cost (args
[i
].value
, SET
, optimize_insn_for_speed_p ())
719 && targetm
.small_register_classes_for_mode_p (args
[i
].mode
))
721 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
725 #ifdef REG_PARM_STACK_SPACE
727 /* The argument list is the property of the called routine and it
728 may clobber it. If the fixed area has been used for previous
729 parameters, we must save and restore it. */
732 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
737 /* Compute the boundary of the area that needs to be saved, if any. */
738 high
= reg_parm_stack_space
;
739 #ifdef ARGS_GROW_DOWNWARD
742 if (high
> highest_outgoing_arg_in_use
)
743 high
= highest_outgoing_arg_in_use
;
745 for (low
= 0; low
< high
; low
++)
746 if (stack_usage_map
[low
] != 0)
749 enum machine_mode save_mode
;
754 while (stack_usage_map
[--high
] == 0)
758 *high_to_save
= high
;
760 num_to_save
= high
- low
+ 1;
761 save_mode
= mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
763 /* If we don't have the required alignment, must do this
765 if ((low
& (MIN (GET_MODE_SIZE (save_mode
),
766 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
769 #ifdef ARGS_GROW_DOWNWARD
774 stack_area
= gen_rtx_MEM (save_mode
,
775 memory_address (save_mode
,
776 plus_constant (argblock
,
779 set_mem_align (stack_area
, PARM_BOUNDARY
);
780 if (save_mode
== BLKmode
)
782 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
783 emit_block_move (validize_mem (save_area
), stack_area
,
784 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
788 save_area
= gen_reg_rtx (save_mode
);
789 emit_move_insn (save_area
, stack_area
);
799 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
801 enum machine_mode save_mode
= GET_MODE (save_area
);
805 #ifdef ARGS_GROW_DOWNWARD
806 delta
= -high_to_save
;
810 stack_area
= gen_rtx_MEM (save_mode
,
811 memory_address (save_mode
,
812 plus_constant (argblock
, delta
)));
813 set_mem_align (stack_area
, PARM_BOUNDARY
);
815 if (save_mode
!= BLKmode
)
816 emit_move_insn (stack_area
, save_area
);
818 emit_block_move (stack_area
, validize_mem (save_area
),
819 GEN_INT (high_to_save
- low_to_save
+ 1),
822 #endif /* REG_PARM_STACK_SPACE */
824 /* If any elements in ARGS refer to parameters that are to be passed in
825 registers, but not in memory, and whose alignment does not permit a
826 direct copy into registers. Copy the values into a group of pseudos
827 which we will later copy into the appropriate hard registers.
829 Pseudos for each unaligned argument will be stored into the array
830 args[argnum].aligned_regs. The caller is responsible for deallocating
831 the aligned_regs array if it is nonzero. */
834 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
838 for (i
= 0; i
< num_actuals
; i
++)
839 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
840 && args
[i
].mode
== BLKmode
841 && MEM_P (args
[i
].value
)
842 && (MEM_ALIGN (args
[i
].value
)
843 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
845 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
846 int endian_correction
= 0;
850 gcc_assert (args
[i
].partial
% UNITS_PER_WORD
== 0);
851 args
[i
].n_aligned_regs
= args
[i
].partial
/ UNITS_PER_WORD
;
855 args
[i
].n_aligned_regs
856 = (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
859 args
[i
].aligned_regs
= XNEWVEC (rtx
, args
[i
].n_aligned_regs
);
861 /* Structures smaller than a word are normally aligned to the
862 least significant byte. On a BYTES_BIG_ENDIAN machine,
863 this means we must skip the empty high order bytes when
864 calculating the bit offset. */
865 if (bytes
< UNITS_PER_WORD
866 #ifdef BLOCK_REG_PADDING
867 && (BLOCK_REG_PADDING (args
[i
].mode
,
868 TREE_TYPE (args
[i
].tree_value
), 1)
874 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
876 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
878 rtx reg
= gen_reg_rtx (word_mode
);
879 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
880 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
882 args
[i
].aligned_regs
[j
] = reg
;
883 word
= extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
884 word_mode
, word_mode
);
886 /* There is no need to restrict this code to loading items
887 in TYPE_ALIGN sized hunks. The bitfield instructions can
888 load up entire word sized registers efficiently.
890 ??? This may not be needed anymore.
891 We use to emit a clobber here but that doesn't let later
892 passes optimize the instructions we emit. By storing 0 into
893 the register later passes know the first AND to zero out the
894 bitfield being set in the register is unnecessary. The store
895 of 0 will be deleted as will at least the first AND. */
897 emit_move_insn (reg
, const0_rtx
);
899 bytes
-= bitsize
/ BITS_PER_UNIT
;
900 store_bit_field (reg
, bitsize
, endian_correction
, word_mode
,
906 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
909 NUM_ACTUALS is the total number of parameters.
911 N_NAMED_ARGS is the total number of named arguments.
913 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
916 FNDECL is the tree code for the target of this call (if known)
918 ARGS_SO_FAR holds state needed by the target to know where to place
921 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
922 for arguments which are passed in registers.
924 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
925 and may be modified by this routine.
927 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
928 flags which may may be modified by this routine.
930 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
931 that requires allocation of stack space.
933 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
934 the thunked-to function. */
937 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
938 struct arg_data
*args
,
939 struct args_size
*args_size
,
940 int n_named_args ATTRIBUTE_UNUSED
,
941 tree exp
, tree struct_value_addr_value
,
942 tree fndecl
, tree fntype
,
943 CUMULATIVE_ARGS
*args_so_far
,
944 int reg_parm_stack_space
,
945 rtx
*old_stack_level
, int *old_pending_adj
,
946 int *must_preallocate
, int *ecf_flags
,
947 bool *may_tailcall
, bool call_from_thunk_p
)
949 location_t loc
= EXPR_LOCATION (exp
);
950 /* 1 if scanning parms front to back, -1 if scanning back to front. */
953 /* Count arg position in order args appear. */
958 args_size
->constant
= 0;
961 /* In this loop, we consider args in the order they are written.
962 We fill up ARGS from the front or from the back if necessary
963 so that in any case the first arg to be pushed ends up at the front. */
965 if (PUSH_ARGS_REVERSED
)
967 i
= num_actuals
- 1, inc
= -1;
968 /* In this case, must reverse order of args
969 so that we compute and push the last arg first. */
976 /* First fill in the actual arguments in the ARGS array, splitting
977 complex arguments if necessary. */
980 call_expr_arg_iterator iter
;
983 if (struct_value_addr_value
)
985 args
[j
].tree_value
= struct_value_addr_value
;
988 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
990 tree argtype
= TREE_TYPE (arg
);
991 if (targetm
.calls
.split_complex_arg
993 && TREE_CODE (argtype
) == COMPLEX_TYPE
994 && targetm
.calls
.split_complex_arg (argtype
))
996 tree subtype
= TREE_TYPE (argtype
);
997 args
[j
].tree_value
= build1 (REALPART_EXPR
, subtype
, arg
);
999 args
[j
].tree_value
= build1 (IMAGPART_EXPR
, subtype
, arg
);
1002 args
[j
].tree_value
= arg
;
1007 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1008 for (argpos
= 0; argpos
< num_actuals
; i
+= inc
, argpos
++)
1010 tree type
= TREE_TYPE (args
[i
].tree_value
);
1012 enum machine_mode mode
;
1014 /* Replace erroneous argument with constant zero. */
1015 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1016 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1018 /* If TYPE is a transparent union or record, pass things the way
1019 we would pass the first field of the union or record. We have
1020 already verified that the modes are the same. */
1021 if ((TREE_CODE (type
) == UNION_TYPE
|| TREE_CODE (type
) == RECORD_TYPE
)
1022 && TYPE_TRANSPARENT_AGGR (type
))
1023 type
= TREE_TYPE (first_field (type
));
1025 /* Decide where to pass this arg.
1027 args[i].reg is nonzero if all or part is passed in registers.
1029 args[i].partial is nonzero if part but not all is passed in registers,
1030 and the exact value says how many bytes are passed in registers.
1032 args[i].pass_on_stack is nonzero if the argument must at least be
1033 computed on the stack. It may then be loaded back into registers
1034 if args[i].reg is nonzero.
1036 These decisions are driven by the FUNCTION_... macros and must agree
1037 with those made by function.c. */
1039 /* See if this argument should be passed by invisible reference. */
1040 if (pass_by_reference (args_so_far
, TYPE_MODE (type
),
1041 type
, argpos
< n_named_args
))
1047 = reference_callee_copied (args_so_far
, TYPE_MODE (type
),
1048 type
, argpos
< n_named_args
);
1050 /* If we're compiling a thunk, pass through invisible references
1051 instead of making a copy. */
1052 if (call_from_thunk_p
1054 && !TREE_ADDRESSABLE (type
)
1055 && (base
= get_base_address (args
[i
].tree_value
))
1056 && TREE_CODE (base
) != SSA_NAME
1057 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
)))))
1059 /* We can't use sibcalls if a callee-copied argument is
1060 stored in the current function's frame. */
1061 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
1062 *may_tailcall
= false;
1064 args
[i
].tree_value
= build_fold_addr_expr_loc (loc
,
1065 args
[i
].tree_value
);
1066 type
= TREE_TYPE (args
[i
].tree_value
);
1068 if (*ecf_flags
& ECF_CONST
)
1069 *ecf_flags
&= ~(ECF_CONST
| ECF_LOOPING_CONST_OR_PURE
);
1073 /* We make a copy of the object and pass the address to the
1074 function being called. */
1077 if (!COMPLETE_TYPE_P (type
)
1078 || TREE_CODE (TYPE_SIZE_UNIT (type
)) != INTEGER_CST
1079 || (flag_stack_check
== GENERIC_STACK_CHECK
1080 && compare_tree_int (TYPE_SIZE_UNIT (type
),
1081 STACK_CHECK_MAX_VAR_SIZE
) > 0))
1083 /* This is a variable-sized object. Make space on the stack
1085 rtx size_rtx
= expr_size (args
[i
].tree_value
);
1087 if (*old_stack_level
== 0)
1089 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1090 *old_pending_adj
= pending_stack_adjust
;
1091 pending_stack_adjust
= 0;
1094 copy
= gen_rtx_MEM (BLKmode
,
1095 allocate_dynamic_stack_space
1096 (size_rtx
, NULL_RTX
, TYPE_ALIGN (type
)));
1097 set_mem_attributes (copy
, type
, 1);
1100 copy
= assign_temp (type
, 0, 1, 0);
1102 store_expr (args
[i
].tree_value
, copy
, 0, false);
1104 /* Just change the const function to pure and then let
1105 the next test clear the pure based on
1107 if (*ecf_flags
& ECF_CONST
)
1109 *ecf_flags
&= ~ECF_CONST
;
1110 *ecf_flags
|= ECF_PURE
;
1113 if (!callee_copies
&& *ecf_flags
& ECF_PURE
)
1114 *ecf_flags
&= ~(ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
1117 = build_fold_addr_expr_loc (loc
, make_tree (type
, copy
));
1118 type
= TREE_TYPE (args
[i
].tree_value
);
1119 *may_tailcall
= false;
1123 unsignedp
= TYPE_UNSIGNED (type
);
1124 mode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
1125 fndecl
? TREE_TYPE (fndecl
) : fntype
, 0);
1127 args
[i
].unsignedp
= unsignedp
;
1128 args
[i
].mode
= mode
;
1130 args
[i
].reg
= targetm
.calls
.function_arg (args_so_far
, mode
, type
,
1131 argpos
< n_named_args
);
1133 /* If this is a sibling call and the machine has register windows, the
1134 register window has to be unwinded before calling the routine, so
1135 arguments have to go into the incoming registers. */
1136 if (targetm
.calls
.function_incoming_arg
!= targetm
.calls
.function_arg
)
1137 args
[i
].tail_call_reg
1138 = targetm
.calls
.function_incoming_arg (args_so_far
, mode
, type
,
1139 argpos
< n_named_args
);
1141 args
[i
].tail_call_reg
= args
[i
].reg
;
1145 = targetm
.calls
.arg_partial_bytes (args_so_far
, mode
, type
,
1146 argpos
< n_named_args
);
1148 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (mode
, type
);
1150 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1151 it means that we are to pass this arg in the register(s) designated
1152 by the PARALLEL, but also to pass it in the stack. */
1153 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1154 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1155 args
[i
].pass_on_stack
= 1;
1157 /* If this is an addressable type, we must preallocate the stack
1158 since we must evaluate the object into its final location.
1160 If this is to be passed in both registers and the stack, it is simpler
1162 if (TREE_ADDRESSABLE (type
)
1163 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1164 *must_preallocate
= 1;
1166 /* Compute the stack-size of this argument. */
1167 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1168 || reg_parm_stack_space
> 0
1169 || args
[i
].pass_on_stack
)
1170 locate_and_pad_parm (mode
, type
,
1171 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1176 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
1177 fndecl
, args_size
, &args
[i
].locate
);
1178 #ifdef BLOCK_REG_PADDING
1180 /* The argument is passed entirely in registers. See at which
1181 end it should be padded. */
1182 args
[i
].locate
.where_pad
=
1183 BLOCK_REG_PADDING (mode
, type
,
1184 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
1187 /* Update ARGS_SIZE, the total stack space for args so far. */
1189 args_size
->constant
+= args
[i
].locate
.size
.constant
;
1190 if (args
[i
].locate
.size
.var
)
1191 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
1193 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1194 have been used, etc. */
1196 targetm
.calls
.function_arg_advance (args_so_far
, TYPE_MODE (type
),
1197 type
, argpos
< n_named_args
);
1201 /* Update ARGS_SIZE to contain the total size for the argument block.
1202 Return the original constant component of the argument block's size.
1204 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1205 for arguments passed in registers. */
1208 compute_argument_block_size (int reg_parm_stack_space
,
1209 struct args_size
*args_size
,
1210 tree fndecl ATTRIBUTE_UNUSED
,
1211 tree fntype ATTRIBUTE_UNUSED
,
1212 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
1214 int unadjusted_args_size
= args_size
->constant
;
1216 /* For accumulate outgoing args mode we don't need to align, since the frame
1217 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1218 backends from generating misaligned frame sizes. */
1219 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1220 preferred_stack_boundary
= STACK_BOUNDARY
;
1222 /* Compute the actual size of the argument block required. The variable
1223 and constant sizes must be combined, the size may have to be rounded,
1224 and there may be a minimum required size. */
1228 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1229 args_size
->constant
= 0;
1231 preferred_stack_boundary
/= BITS_PER_UNIT
;
1232 if (preferred_stack_boundary
> 1)
1234 /* We don't handle this case yet. To handle it correctly we have
1235 to add the delta, round and subtract the delta.
1236 Currently no machine description requires this support. */
1237 gcc_assert (!(stack_pointer_delta
& (preferred_stack_boundary
- 1)));
1238 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1241 if (reg_parm_stack_space
> 0)
1244 = size_binop (MAX_EXPR
, args_size
->var
,
1245 ssize_int (reg_parm_stack_space
));
1247 /* The area corresponding to register parameters is not to count in
1248 the size of the block we need. So make the adjustment. */
1249 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
1251 = size_binop (MINUS_EXPR
, args_size
->var
,
1252 ssize_int (reg_parm_stack_space
));
1257 preferred_stack_boundary
/= BITS_PER_UNIT
;
1258 if (preferred_stack_boundary
< 1)
1259 preferred_stack_boundary
= 1;
1260 args_size
->constant
= (((args_size
->constant
1261 + stack_pointer_delta
1262 + preferred_stack_boundary
- 1)
1263 / preferred_stack_boundary
1264 * preferred_stack_boundary
)
1265 - stack_pointer_delta
);
1267 args_size
->constant
= MAX (args_size
->constant
,
1268 reg_parm_stack_space
);
1270 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
1271 args_size
->constant
-= reg_parm_stack_space
;
1273 return unadjusted_args_size
;
1276 /* Precompute parameters as needed for a function call.
1278 FLAGS is mask of ECF_* constants.
1280 NUM_ACTUALS is the number of arguments.
1282 ARGS is an array containing information for each argument; this
1283 routine fills in the INITIAL_VALUE and VALUE fields for each
1284 precomputed argument. */
1287 precompute_arguments (int num_actuals
, struct arg_data
*args
)
1291 /* If this is a libcall, then precompute all arguments so that we do not
1292 get extraneous instructions emitted as part of the libcall sequence. */
1294 /* If we preallocated the stack space, and some arguments must be passed
1295 on the stack, then we must precompute any parameter which contains a
1296 function call which will store arguments on the stack.
1297 Otherwise, evaluating the parameter may clobber previous parameters
1298 which have already been stored into the stack. (we have code to avoid
1299 such case by saving the outgoing stack arguments, but it results in
1301 if (!ACCUMULATE_OUTGOING_ARGS
)
1304 for (i
= 0; i
< num_actuals
; i
++)
1307 enum machine_mode mode
;
1309 if (TREE_CODE (args
[i
].tree_value
) != CALL_EXPR
)
1312 /* If this is an addressable type, we cannot pre-evaluate it. */
1313 type
= TREE_TYPE (args
[i
].tree_value
);
1314 gcc_assert (!TREE_ADDRESSABLE (type
));
1316 args
[i
].initial_value
= args
[i
].value
1317 = expand_normal (args
[i
].tree_value
);
1319 mode
= TYPE_MODE (type
);
1320 if (mode
!= args
[i
].mode
)
1322 int unsignedp
= args
[i
].unsignedp
;
1324 = convert_modes (args
[i
].mode
, mode
,
1325 args
[i
].value
, args
[i
].unsignedp
);
1327 /* CSE will replace this only if it contains args[i].value
1328 pseudo, so convert it down to the declared mode using
1330 if (REG_P (args
[i
].value
)
1331 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
1332 && promote_mode (type
, mode
, &unsignedp
) != args
[i
].mode
)
1334 args
[i
].initial_value
1335 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1336 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1337 SUBREG_PROMOTED_UNSIGNED_SET (args
[i
].initial_value
,
1344 /* Given the current state of MUST_PREALLOCATE and information about
1345 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1346 compute and return the final value for MUST_PREALLOCATE. */
1349 finalize_must_preallocate (int must_preallocate
, int num_actuals
,
1350 struct arg_data
*args
, struct args_size
*args_size
)
1352 /* See if we have or want to preallocate stack space.
1354 If we would have to push a partially-in-regs parm
1355 before other stack parms, preallocate stack space instead.
1357 If the size of some parm is not a multiple of the required stack
1358 alignment, we must preallocate.
1360 If the total size of arguments that would otherwise create a copy in
1361 a temporary (such as a CALL) is more than half the total argument list
1362 size, preallocation is faster.
1364 Another reason to preallocate is if we have a machine (like the m88k)
1365 where stack alignment is required to be maintained between every
1366 pair of insns, not just when the call is made. However, we assume here
1367 that such machines either do not have push insns (and hence preallocation
1368 would occur anyway) or the problem is taken care of with
1371 if (! must_preallocate
)
1373 int partial_seen
= 0;
1374 int copy_to_evaluate_size
= 0;
1377 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1379 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1381 else if (partial_seen
&& args
[i
].reg
== 0)
1382 must_preallocate
= 1;
1384 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1385 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1386 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1387 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1388 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1389 copy_to_evaluate_size
1390 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1393 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1394 && args_size
->constant
> 0)
1395 must_preallocate
= 1;
1397 return must_preallocate
;
1400 /* If we preallocated stack space, compute the address of each argument
1401 and store it into the ARGS array.
1403 We need not ensure it is a valid memory address here; it will be
1404 validized when it is used.
1406 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1409 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
1413 rtx arg_reg
= argblock
;
1414 int i
, arg_offset
= 0;
1416 if (GET_CODE (argblock
) == PLUS
)
1417 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1419 for (i
= 0; i
< num_actuals
; i
++)
1421 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
1422 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
1424 unsigned int align
, boundary
;
1425 unsigned int units_on_stack
= 0;
1426 enum machine_mode partial_mode
= VOIDmode
;
1428 /* Skip this parm if it will not be passed on the stack. */
1429 if (! args
[i
].pass_on_stack
1431 && args
[i
].partial
== 0)
1434 if (CONST_INT_P (offset
))
1435 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1437 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1439 addr
= plus_constant (addr
, arg_offset
);
1441 if (args
[i
].partial
!= 0)
1443 /* Only part of the parameter is being passed on the stack.
1444 Generate a simple memory reference of the correct size. */
1445 units_on_stack
= args
[i
].locate
.size
.constant
;
1446 partial_mode
= mode_for_size (units_on_stack
* BITS_PER_UNIT
,
1448 args
[i
].stack
= gen_rtx_MEM (partial_mode
, addr
);
1449 set_mem_size (args
[i
].stack
, GEN_INT (units_on_stack
));
1453 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1454 set_mem_attributes (args
[i
].stack
,
1455 TREE_TYPE (args
[i
].tree_value
), 1);
1457 align
= BITS_PER_UNIT
;
1458 boundary
= args
[i
].locate
.boundary
;
1459 if (args
[i
].locate
.where_pad
!= downward
)
1461 else if (CONST_INT_P (offset
))
1463 align
= INTVAL (offset
) * BITS_PER_UNIT
| boundary
;
1464 align
= align
& -align
;
1466 set_mem_align (args
[i
].stack
, align
);
1468 if (CONST_INT_P (slot_offset
))
1469 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1471 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1473 addr
= plus_constant (addr
, arg_offset
);
1475 if (args
[i
].partial
!= 0)
1477 /* Only part of the parameter is being passed on the stack.
1478 Generate a simple memory reference of the correct size.
1480 args
[i
].stack_slot
= gen_rtx_MEM (partial_mode
, addr
);
1481 set_mem_size (args
[i
].stack_slot
, GEN_INT (units_on_stack
));
1485 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1486 set_mem_attributes (args
[i
].stack_slot
,
1487 TREE_TYPE (args
[i
].tree_value
), 1);
1489 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
1491 /* Function incoming arguments may overlap with sibling call
1492 outgoing arguments and we cannot allow reordering of reads
1493 from function arguments with stores to outgoing arguments
1494 of sibling calls. */
1495 set_mem_alias_set (args
[i
].stack
, 0);
1496 set_mem_alias_set (args
[i
].stack_slot
, 0);
1501 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1502 in a call instruction.
1504 FNDECL is the tree node for the target function. For an indirect call
1505 FNDECL will be NULL_TREE.
1507 ADDR is the operand 0 of CALL_EXPR for this call. */
1510 rtx_for_function_call (tree fndecl
, tree addr
)
1514 /* Get the function to call, in the form of RTL. */
1517 /* If this is the first use of the function, see if we need to
1518 make an external definition for it. */
1519 if (!TREE_USED (fndecl
) && fndecl
!= current_function_decl
)
1521 assemble_external (fndecl
);
1522 TREE_USED (fndecl
) = 1;
1525 /* Get a SYMBOL_REF rtx for the function address. */
1526 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1529 /* Generate an rtx (probably a pseudo-register) for the address. */
1532 funexp
= expand_normal (addr
);
1533 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1538 /* Return true if and only if SIZE storage units (usually bytes)
1539 starting from address ADDR overlap with already clobbered argument
1540 area. This function is used to determine if we should give up a
1544 mem_overlaps_already_clobbered_arg_p (rtx addr
, unsigned HOST_WIDE_INT size
)
1548 if (addr
== crtl
->args
.internal_arg_pointer
)
1550 else if (GET_CODE (addr
) == PLUS
1551 && XEXP (addr
, 0) == crtl
->args
.internal_arg_pointer
1552 && CONST_INT_P (XEXP (addr
, 1)))
1553 i
= INTVAL (XEXP (addr
, 1));
1554 /* Return true for arg pointer based indexed addressing. */
1555 else if (GET_CODE (addr
) == PLUS
1556 && (XEXP (addr
, 0) == crtl
->args
.internal_arg_pointer
1557 || XEXP (addr
, 1) == crtl
->args
.internal_arg_pointer
))
1562 #ifdef ARGS_GROW_DOWNWARD
1567 unsigned HOST_WIDE_INT k
;
1569 for (k
= 0; k
< size
; k
++)
1570 if (i
+ k
< stored_args_map
->n_bits
1571 && TEST_BIT (stored_args_map
, i
+ k
))
1578 /* Do the register loads required for any wholly-register parms or any
1579 parms which are passed both on the stack and in a register. Their
1580 expressions were already evaluated.
1582 Mark all register-parms as living through the call, putting these USE
1583 insns in the CALL_INSN_FUNCTION_USAGE field.
1585 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1586 checking, setting *SIBCALL_FAILURE if appropriate. */
1589 load_register_parameters (struct arg_data
*args
, int num_actuals
,
1590 rtx
*call_fusage
, int flags
, int is_sibcall
,
1591 int *sibcall_failure
)
1595 for (i
= 0; i
< num_actuals
; i
++)
1597 rtx reg
= ((flags
& ECF_SIBCALL
)
1598 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1601 int partial
= args
[i
].partial
;
1604 rtx before_arg
= get_last_insn ();
1605 /* Set non-negative if we must move a word at a time, even if
1606 just one word (e.g, partial == 4 && mode == DFmode). Set
1607 to -1 if we just use a normal move insn. This value can be
1608 zero if the argument is a zero size structure. */
1610 if (GET_CODE (reg
) == PARALLEL
)
1614 gcc_assert (partial
% UNITS_PER_WORD
== 0);
1615 nregs
= partial
/ UNITS_PER_WORD
;
1617 else if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
)
1619 size
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1620 nregs
= (size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1623 size
= GET_MODE_SIZE (args
[i
].mode
);
1625 /* Handle calls that pass values in multiple non-contiguous
1626 locations. The Irix 6 ABI has examples of this. */
1628 if (GET_CODE (reg
) == PARALLEL
)
1629 emit_group_move (reg
, args
[i
].parallel_value
);
1631 /* If simple case, just do move. If normal partial, store_one_arg
1632 has already loaded the register for us. In all other cases,
1633 load the register(s) from memory. */
1635 else if (nregs
== -1)
1637 emit_move_insn (reg
, args
[i
].value
);
1638 #ifdef BLOCK_REG_PADDING
1639 /* Handle case where we have a value that needs shifting
1640 up to the msb. eg. a QImode value and we're padding
1641 upward on a BYTES_BIG_ENDIAN machine. */
1642 if (size
< UNITS_PER_WORD
1643 && (args
[i
].locate
.where_pad
1644 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
1647 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1649 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1650 report the whole reg as used. Strictly speaking, the
1651 call only uses SIZE bytes at the msb end, but it doesn't
1652 seem worth generating rtl to say that. */
1653 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
1654 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
1655 build_int_cst (NULL_TREE
, shift
),
1658 emit_move_insn (reg
, x
);
1663 /* If we have pre-computed the values to put in the registers in
1664 the case of non-aligned structures, copy them in now. */
1666 else if (args
[i
].n_aligned_regs
!= 0)
1667 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1668 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1669 args
[i
].aligned_regs
[j
]);
1671 else if (partial
== 0 || args
[i
].pass_on_stack
)
1673 rtx mem
= validize_mem (args
[i
].value
);
1675 /* Check for overlap with already clobbered argument area,
1676 providing that this has non-zero size. */
1679 || mem_overlaps_already_clobbered_arg_p
1680 (XEXP (args
[i
].value
, 0), size
)))
1681 *sibcall_failure
= 1;
1683 /* Handle a BLKmode that needs shifting. */
1684 if (nregs
== 1 && size
< UNITS_PER_WORD
1685 #ifdef BLOCK_REG_PADDING
1686 && args
[i
].locate
.where_pad
== downward
1692 rtx tem
= operand_subword_force (mem
, 0, args
[i
].mode
);
1693 rtx ri
= gen_rtx_REG (word_mode
, REGNO (reg
));
1694 rtx x
= gen_reg_rtx (word_mode
);
1695 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1696 enum tree_code dir
= BYTES_BIG_ENDIAN
? RSHIFT_EXPR
1699 emit_move_insn (x
, tem
);
1700 x
= expand_shift (dir
, word_mode
, x
,
1701 build_int_cst (NULL_TREE
, shift
),
1704 emit_move_insn (ri
, x
);
1707 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
1710 /* When a parameter is a block, and perhaps in other cases, it is
1711 possible that it did a load from an argument slot that was
1712 already clobbered. */
1714 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
1715 *sibcall_failure
= 1;
1717 /* Handle calls that pass values in multiple non-contiguous
1718 locations. The Irix 6 ABI has examples of this. */
1719 if (GET_CODE (reg
) == PARALLEL
)
1720 use_group_regs (call_fusage
, reg
);
1721 else if (nregs
== -1)
1722 use_reg (call_fusage
, reg
);
1724 use_regs (call_fusage
, REGNO (reg
), nregs
);
1729 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1730 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1731 bytes, then we would need to push some additional bytes to pad the
1732 arguments. So, we compute an adjust to the stack pointer for an
1733 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1734 bytes. Then, when the arguments are pushed the stack will be perfectly
1735 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1736 be popped after the call. Returns the adjustment. */
1739 combine_pending_stack_adjustment_and_call (int unadjusted_args_size
,
1740 struct args_size
*args_size
,
1741 unsigned int preferred_unit_stack_boundary
)
1743 /* The number of bytes to pop so that the stack will be
1744 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1745 HOST_WIDE_INT adjustment
;
1746 /* The alignment of the stack after the arguments are pushed, if we
1747 just pushed the arguments without adjust the stack here. */
1748 unsigned HOST_WIDE_INT unadjusted_alignment
;
1750 unadjusted_alignment
1751 = ((stack_pointer_delta
+ unadjusted_args_size
)
1752 % preferred_unit_stack_boundary
);
1754 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1755 as possible -- leaving just enough left to cancel out the
1756 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1757 PENDING_STACK_ADJUST is non-negative, and congruent to
1758 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1760 /* Begin by trying to pop all the bytes. */
1761 unadjusted_alignment
1762 = (unadjusted_alignment
1763 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1764 adjustment
= pending_stack_adjust
;
1765 /* Push enough additional bytes that the stack will be aligned
1766 after the arguments are pushed. */
1767 if (preferred_unit_stack_boundary
> 1)
1769 if (unadjusted_alignment
> 0)
1770 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1772 adjustment
+= unadjusted_alignment
;
1775 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1776 bytes after the call. The right number is the entire
1777 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1778 by the arguments in the first place. */
1780 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1785 /* Scan X expression if it does not dereference any argument slots
1786 we already clobbered by tail call arguments (as noted in stored_args_map
1788 Return nonzero if X expression dereferences such argument slots,
1792 check_sibcall_argument_overlap_1 (rtx x
)
1801 code
= GET_CODE (x
);
1804 return mem_overlaps_already_clobbered_arg_p (XEXP (x
, 0),
1805 GET_MODE_SIZE (GET_MODE (x
)));
1807 /* Scan all subexpressions. */
1808 fmt
= GET_RTX_FORMAT (code
);
1809 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
1813 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
1816 else if (*fmt
== 'E')
1818 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
1819 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
1826 /* Scan sequence after INSN if it does not dereference any argument slots
1827 we already clobbered by tail call arguments (as noted in stored_args_map
1828 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1829 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1830 should be 0). Return nonzero if sequence after INSN dereferences such argument
1831 slots, zero otherwise. */
1834 check_sibcall_argument_overlap (rtx insn
, struct arg_data
*arg
, int mark_stored_args_map
)
1838 if (insn
== NULL_RTX
)
1839 insn
= get_insns ();
1841 insn
= NEXT_INSN (insn
);
1843 for (; insn
; insn
= NEXT_INSN (insn
))
1845 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
1848 if (mark_stored_args_map
)
1850 #ifdef ARGS_GROW_DOWNWARD
1851 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
1853 low
= arg
->locate
.slot_offset
.constant
;
1856 for (high
= low
+ arg
->locate
.size
.constant
; low
< high
; low
++)
1857 SET_BIT (stored_args_map
, low
);
1859 return insn
!= NULL_RTX
;
1862 /* Given that a function returns a value of mode MODE at the most
1863 significant end of hard register VALUE, shift VALUE left or right
1864 as specified by LEFT_P. Return true if some action was needed. */
1867 shift_return_value (enum machine_mode mode
, bool left_p
, rtx value
)
1869 HOST_WIDE_INT shift
;
1871 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
1872 shift
= GET_MODE_BITSIZE (GET_MODE (value
)) - GET_MODE_BITSIZE (mode
);
1876 /* Use ashr rather than lshr for right shifts. This is for the benefit
1877 of the MIPS port, which requires SImode values to be sign-extended
1878 when stored in 64-bit registers. */
1879 if (!force_expand_binop (GET_MODE (value
), left_p
? ashl_optab
: ashr_optab
,
1880 value
, GEN_INT (shift
), value
, 1, OPTAB_WIDEN
))
1885 /* If X is a likely-spilled register value, copy it to a pseudo
1886 register and return that register. Return X otherwise. */
1889 avoid_likely_spilled_reg (rtx x
)
1894 && HARD_REGISTER_P (x
)
1895 && CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (REGNO (x
))))
1897 /* Make sure that we generate a REG rather than a CONCAT.
1898 Moves into CONCATs can need nontrivial instructions,
1899 and the whole point of this function is to avoid
1900 using the hard register directly in such a situation. */
1901 generating_concat_p
= 0;
1902 new_rtx
= gen_reg_rtx (GET_MODE (x
));
1903 generating_concat_p
= 1;
1904 emit_move_insn (new_rtx
, x
);
1910 /* Generate all the code for a CALL_EXPR exp
1911 and return an rtx for its value.
1912 Store the value in TARGET (specified as an rtx) if convenient.
1913 If the value is stored in TARGET then TARGET is returned.
1914 If IGNORE is nonzero, then we ignore the value of the function call. */
1917 expand_call (tree exp
, rtx target
, int ignore
)
1919 /* Nonzero if we are currently expanding a call. */
1920 static int currently_expanding_call
= 0;
1922 /* RTX for the function to be called. */
1924 /* Sequence of insns to perform a normal "call". */
1925 rtx normal_call_insns
= NULL_RTX
;
1926 /* Sequence of insns to perform a tail "call". */
1927 rtx tail_call_insns
= NULL_RTX
;
1928 /* Data type of the function. */
1930 tree type_arg_types
;
1932 /* Declaration of the function being called,
1933 or 0 if the function is computed (not known by name). */
1935 /* The type of the function being called. */
1937 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
1940 /* Register in which non-BLKmode value will be returned,
1941 or 0 if no value or if value is BLKmode. */
1943 /* Address where we should return a BLKmode value;
1944 0 if value not BLKmode. */
1945 rtx structure_value_addr
= 0;
1946 /* Nonzero if that address is being passed by treating it as
1947 an extra, implicit first parameter. Otherwise,
1948 it is passed by being copied directly into struct_value_rtx. */
1949 int structure_value_addr_parm
= 0;
1950 /* Holds the value of implicit argument for the struct value. */
1951 tree structure_value_addr_value
= NULL_TREE
;
1952 /* Size of aggregate value wanted, or zero if none wanted
1953 or if we are using the non-reentrant PCC calling convention
1954 or expecting the value in registers. */
1955 HOST_WIDE_INT struct_value_size
= 0;
1956 /* Nonzero if called function returns an aggregate in memory PCC style,
1957 by returning the address of where to find it. */
1958 int pcc_struct_value
= 0;
1959 rtx struct_value
= 0;
1961 /* Number of actual parameters in this call, including struct value addr. */
1963 /* Number of named args. Args after this are anonymous ones
1964 and they must all go on the stack. */
1966 /* Number of complex actual arguments that need to be split. */
1967 int num_complex_actuals
= 0;
1969 /* Vector of information about each argument.
1970 Arguments are numbered in the order they will be pushed,
1971 not the order they are written. */
1972 struct arg_data
*args
;
1974 /* Total size in bytes of all the stack-parms scanned so far. */
1975 struct args_size args_size
;
1976 struct args_size adjusted_args_size
;
1977 /* Size of arguments before any adjustments (such as rounding). */
1978 int unadjusted_args_size
;
1979 /* Data on reg parms scanned so far. */
1980 CUMULATIVE_ARGS args_so_far
;
1981 /* Nonzero if a reg parm has been scanned. */
1983 /* Nonzero if this is an indirect function call. */
1985 /* Nonzero if we must avoid push-insns in the args for this call.
1986 If stack space is allocated for register parameters, but not by the
1987 caller, then it is preallocated in the fixed part of the stack frame.
1988 So the entire argument block must then be preallocated (i.e., we
1989 ignore PUSH_ROUNDING in that case). */
1991 int must_preallocate
= !PUSH_ARGS
;
1993 /* Size of the stack reserved for parameter registers. */
1994 int reg_parm_stack_space
= 0;
1996 /* Address of space preallocated for stack parms
1997 (on machines that lack push insns), or 0 if space not preallocated. */
2000 /* Mask of ECF_ flags. */
2002 #ifdef REG_PARM_STACK_SPACE
2003 /* Define the boundary of the register parm stack space that needs to be
2005 int low_to_save
, high_to_save
;
2006 rtx save_area
= 0; /* Place that it is saved */
2009 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
2010 char *initial_stack_usage_map
= stack_usage_map
;
2011 char *stack_usage_map_buf
= NULL
;
2013 int old_stack_allocated
;
2015 /* State variables to track stack modifications. */
2016 rtx old_stack_level
= 0;
2017 int old_stack_arg_under_construction
= 0;
2018 int old_pending_adj
= 0;
2019 int old_inhibit_defer_pop
= inhibit_defer_pop
;
2021 /* Some stack pointer alterations we make are performed via
2022 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2023 which we then also need to save/restore along the way. */
2024 int old_stack_pointer_delta
= 0;
2027 tree addr
= CALL_EXPR_FN (exp
);
2029 /* The alignment of the stack, in bits. */
2030 unsigned HOST_WIDE_INT preferred_stack_boundary
;
2031 /* The alignment of the stack, in bytes. */
2032 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
2033 /* The static chain value to use for this call. */
2034 rtx static_chain_value
;
2035 /* See if this is "nothrow" function call. */
2036 if (TREE_NOTHROW (exp
))
2037 flags
|= ECF_NOTHROW
;
2039 /* See if we can find a DECL-node for the actual function, and get the
2040 function attributes (flags) from the function decl or type node. */
2041 fndecl
= get_callee_fndecl (exp
);
2044 fntype
= TREE_TYPE (fndecl
);
2045 flags
|= flags_from_decl_or_type (fndecl
);
2049 fntype
= TREE_TYPE (TREE_TYPE (addr
));
2050 flags
|= flags_from_decl_or_type (fntype
);
2052 rettype
= TREE_TYPE (exp
);
2054 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
2056 /* Warn if this value is an aggregate type,
2057 regardless of which calling convention we are using for it. */
2058 if (AGGREGATE_TYPE_P (rettype
))
2059 warning (OPT_Waggregate_return
, "function call has aggregate value");
2061 /* If the result of a non looping pure or const function call is
2062 ignored (or void), and none of its arguments are volatile, we can
2063 avoid expanding the call and just evaluate the arguments for
2065 if ((flags
& (ECF_CONST
| ECF_PURE
))
2066 && (!(flags
& ECF_LOOPING_CONST_OR_PURE
))
2067 && (ignore
|| target
== const0_rtx
2068 || TYPE_MODE (rettype
) == VOIDmode
))
2070 bool volatilep
= false;
2072 call_expr_arg_iterator iter
;
2074 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2075 if (TREE_THIS_VOLATILE (arg
))
2083 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2084 expand_expr (arg
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
2089 #ifdef REG_PARM_STACK_SPACE
2090 reg_parm_stack_space
= REG_PARM_STACK_SPACE (!fndecl
? fntype
: fndecl
);
2093 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
2094 && reg_parm_stack_space
> 0 && PUSH_ARGS
)
2095 must_preallocate
= 1;
2097 /* Set up a place to return a structure. */
2099 /* Cater to broken compilers. */
2100 if (aggregate_value_p (exp
, fntype
))
2102 /* This call returns a big structure. */
2103 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
2105 #ifdef PCC_STATIC_STRUCT_RETURN
2107 pcc_struct_value
= 1;
2109 #else /* not PCC_STATIC_STRUCT_RETURN */
2111 struct_value_size
= int_size_in_bytes (rettype
);
2113 if (target
&& MEM_P (target
) && CALL_EXPR_RETURN_SLOT_OPT (exp
))
2114 structure_value_addr
= XEXP (target
, 0);
2117 /* For variable-sized objects, we must be called with a target
2118 specified. If we were to allocate space on the stack here,
2119 we would have no way of knowing when to free it. */
2120 rtx d
= assign_temp (rettype
, 0, 1, 1);
2122 mark_temp_addr_taken (d
);
2123 structure_value_addr
= XEXP (d
, 0);
2127 #endif /* not PCC_STATIC_STRUCT_RETURN */
2130 /* Figure out the amount to which the stack should be aligned. */
2131 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2134 struct cgraph_rtl_info
*i
= cgraph_rtl_info (fndecl
);
2135 /* Without automatic stack alignment, we can't increase preferred
2136 stack boundary. With automatic stack alignment, it is
2137 unnecessary since unless we can guarantee that all callers will
2138 align the outgoing stack properly, callee has to align its
2141 && i
->preferred_incoming_stack_boundary
2142 && i
->preferred_incoming_stack_boundary
< preferred_stack_boundary
)
2143 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
2146 /* Operand 0 is a pointer-to-function; get the type of the function. */
2147 funtype
= TREE_TYPE (addr
);
2148 gcc_assert (POINTER_TYPE_P (funtype
));
2149 funtype
= TREE_TYPE (funtype
);
2151 /* Count whether there are actual complex arguments that need to be split
2152 into their real and imaginary parts. Munge the type_arg_types
2153 appropriately here as well. */
2154 if (targetm
.calls
.split_complex_arg
)
2156 call_expr_arg_iterator iter
;
2158 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2160 tree type
= TREE_TYPE (arg
);
2161 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
2162 && targetm
.calls
.split_complex_arg (type
))
2163 num_complex_actuals
++;
2165 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
2168 type_arg_types
= TYPE_ARG_TYPES (funtype
);
2170 if (flags
& ECF_MAY_BE_ALLOCA
)
2171 cfun
->calls_alloca
= 1;
2173 /* If struct_value_rtx is 0, it means pass the address
2174 as if it were an extra parameter. Put the argument expression
2175 in structure_value_addr_value. */
2176 if (structure_value_addr
&& struct_value
== 0)
2178 /* If structure_value_addr is a REG other than
2179 virtual_outgoing_args_rtx, we can use always use it. If it
2180 is not a REG, we must always copy it into a register.
2181 If it is virtual_outgoing_args_rtx, we must copy it to another
2182 register in some cases. */
2183 rtx temp
= (!REG_P (structure_value_addr
)
2184 || (ACCUMULATE_OUTGOING_ARGS
2185 && stack_arg_under_construction
2186 && structure_value_addr
== virtual_outgoing_args_rtx
)
2187 ? copy_addr_to_reg (convert_memory_address
2188 (Pmode
, structure_value_addr
))
2189 : structure_value_addr
);
2191 structure_value_addr_value
=
2192 make_tree (build_pointer_type (TREE_TYPE (funtype
)), temp
);
2193 structure_value_addr_parm
= 1;
2196 /* Count the arguments and set NUM_ACTUALS. */
2198 call_expr_nargs (exp
) + num_complex_actuals
+ structure_value_addr_parm
;
2200 /* Compute number of named args.
2201 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2203 if (type_arg_types
!= 0)
2205 = (list_length (type_arg_types
)
2206 /* Count the struct value address, if it is passed as a parm. */
2207 + structure_value_addr_parm
);
2209 /* If we know nothing, treat all args as named. */
2210 n_named_args
= num_actuals
;
2212 /* Start updating where the next arg would go.
2214 On some machines (such as the PA) indirect calls have a different
2215 calling convention than normal calls. The fourth argument in
2216 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2218 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
2220 /* Now possibly adjust the number of named args.
2221 Normally, don't include the last named arg if anonymous args follow.
2222 We do include the last named arg if
2223 targetm.calls.strict_argument_naming() returns nonzero.
2224 (If no anonymous args follow, the result of list_length is actually
2225 one too large. This is harmless.)
2227 If targetm.calls.pretend_outgoing_varargs_named() returns
2228 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2229 this machine will be able to place unnamed args that were passed
2230 in registers into the stack. So treat all args as named. This
2231 allows the insns emitting for a specific argument list to be
2232 independent of the function declaration.
2234 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2235 we do not have any reliable way to pass unnamed args in
2236 registers, so we must force them into memory. */
2238 if (type_arg_types
!= 0
2239 && targetm
.calls
.strict_argument_naming (&args_so_far
))
2241 else if (type_arg_types
!= 0
2242 && ! targetm
.calls
.pretend_outgoing_varargs_named (&args_so_far
))
2243 /* Don't include the last named arg. */
2246 /* Treat all args as named. */
2247 n_named_args
= num_actuals
;
2249 /* Make a vector to hold all the information about each arg. */
2250 args
= XALLOCAVEC (struct arg_data
, num_actuals
);
2251 memset (args
, 0, num_actuals
* sizeof (struct arg_data
));
2253 /* Build up entries in the ARGS array, compute the size of the
2254 arguments into ARGS_SIZE, etc. */
2255 initialize_argument_information (num_actuals
, args
, &args_size
,
2257 structure_value_addr_value
, fndecl
, fntype
,
2258 &args_so_far
, reg_parm_stack_space
,
2259 &old_stack_level
, &old_pending_adj
,
2260 &must_preallocate
, &flags
,
2261 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
2264 must_preallocate
= 1;
2266 /* Now make final decision about preallocating stack space. */
2267 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2271 /* If the structure value address will reference the stack pointer, we
2272 must stabilize it. We don't need to do this if we know that we are
2273 not going to adjust the stack pointer in processing this call. */
2275 if (structure_value_addr
2276 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2277 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2278 structure_value_addr
))
2280 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2281 structure_value_addr
= copy_to_reg (structure_value_addr
);
2283 /* Tail calls can make things harder to debug, and we've traditionally
2284 pushed these optimizations into -O2. Don't try if we're already
2285 expanding a call, as that means we're an argument. Don't try if
2286 there's cleanups, as we know there's code to follow the call. */
2288 if (currently_expanding_call
++ != 0
2289 || !flag_optimize_sibling_calls
2291 || dbg_cnt (tail_call
) == false)
2294 /* Rest of purposes for tail call optimizations to fail. */
2296 #ifdef HAVE_sibcall_epilogue
2297 !HAVE_sibcall_epilogue
2302 /* Doing sibling call optimization needs some work, since
2303 structure_value_addr can be allocated on the stack.
2304 It does not seem worth the effort since few optimizable
2305 sibling calls will return a structure. */
2306 || structure_value_addr
!= NULL_RTX
2307 #ifdef REG_PARM_STACK_SPACE
2308 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2309 || (OUTGOING_REG_PARM_STACK_SPACE (funtype
)
2310 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl
)))
2311 || (reg_parm_stack_space
!= REG_PARM_STACK_SPACE (fndecl
))
2313 /* Check whether the target is able to optimize the call
2315 || !targetm
.function_ok_for_sibcall (fndecl
, exp
)
2316 /* Functions that do not return exactly once may not be sibcall
2318 || (flags
& (ECF_RETURNS_TWICE
| ECF_NORETURN
))
2319 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
)))
2320 /* If the called function is nested in the current one, it might access
2321 some of the caller's arguments, but could clobber them beforehand if
2322 the argument areas are shared. */
2323 || (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
2324 /* If this function requires more stack slots than the current
2325 function, we cannot change it into a sibling call.
2326 crtl->args.pretend_args_size is not part of the
2327 stack allocated by our caller. */
2328 || args_size
.constant
> (crtl
->args
.size
2329 - crtl
->args
.pretend_args_size
)
2330 /* If the callee pops its own arguments, then it must pop exactly
2331 the same number of arguments as the current function. */
2332 || (targetm
.calls
.return_pops_args (fndecl
, funtype
, args_size
.constant
)
2333 != targetm
.calls
.return_pops_args (current_function_decl
,
2334 TREE_TYPE (current_function_decl
),
2336 || !lang_hooks
.decls
.ok_for_sibcall (fndecl
))
2339 /* Check if caller and callee disagree in promotion of function
2343 enum machine_mode caller_mode
, caller_promoted_mode
;
2344 enum machine_mode callee_mode
, callee_promoted_mode
;
2345 int caller_unsignedp
, callee_unsignedp
;
2346 tree caller_res
= DECL_RESULT (current_function_decl
);
2348 caller_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (caller_res
));
2349 caller_mode
= DECL_MODE (caller_res
);
2350 callee_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (funtype
));
2351 callee_mode
= TYPE_MODE (TREE_TYPE (funtype
));
2352 caller_promoted_mode
2353 = promote_function_mode (TREE_TYPE (caller_res
), caller_mode
,
2355 TREE_TYPE (current_function_decl
), 1);
2356 callee_promoted_mode
2357 = promote_function_mode (TREE_TYPE (funtype
), callee_mode
,
2360 if (caller_mode
!= VOIDmode
2361 && (caller_promoted_mode
!= callee_promoted_mode
2362 || ((caller_mode
!= caller_promoted_mode
2363 || callee_mode
!= callee_promoted_mode
)
2364 && (caller_unsignedp
!= callee_unsignedp
2365 || GET_MODE_BITSIZE (caller_mode
)
2366 < GET_MODE_BITSIZE (callee_mode
)))))
2370 /* Ensure current function's preferred stack boundary is at least
2371 what we need. Stack alignment may also increase preferred stack
2373 if (crtl
->preferred_stack_boundary
< preferred_stack_boundary
)
2374 crtl
->preferred_stack_boundary
= preferred_stack_boundary
;
2376 preferred_stack_boundary
= crtl
->preferred_stack_boundary
;
2378 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2380 /* We want to make two insn chains; one for a sibling call, the other
2381 for a normal call. We will select one of the two chains after
2382 initial RTL generation is complete. */
2383 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
2385 int sibcall_failure
= 0;
2386 /* We want to emit any pending stack adjustments before the tail
2387 recursion "call". That way we know any adjustment after the tail
2388 recursion call can be ignored if we indeed use the tail
2390 int save_pending_stack_adjust
= 0;
2391 int save_stack_pointer_delta
= 0;
2393 rtx before_call
, next_arg_reg
, after_args
;
2397 /* State variables we need to save and restore between
2399 save_pending_stack_adjust
= pending_stack_adjust
;
2400 save_stack_pointer_delta
= stack_pointer_delta
;
2403 flags
&= ~ECF_SIBCALL
;
2405 flags
|= ECF_SIBCALL
;
2407 /* Other state variables that we must reinitialize each time
2408 through the loop (that are not initialized by the loop itself). */
2412 /* Start a new sequence for the normal call case.
2414 From this point on, if the sibling call fails, we want to set
2415 sibcall_failure instead of continuing the loop. */
2418 /* Don't let pending stack adjusts add up to too much.
2419 Also, do all pending adjustments now if there is any chance
2420 this might be a call to alloca or if we are expanding a sibling
2422 Also do the adjustments before a throwing call, otherwise
2423 exception handling can fail; PR 19225. */
2424 if (pending_stack_adjust
>= 32
2425 || (pending_stack_adjust
> 0
2426 && (flags
& ECF_MAY_BE_ALLOCA
))
2427 || (pending_stack_adjust
> 0
2428 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
2430 do_pending_stack_adjust ();
2432 /* Precompute any arguments as needed. */
2434 precompute_arguments (num_actuals
, args
);
2436 /* Now we are about to start emitting insns that can be deleted
2437 if a libcall is deleted. */
2438 if (pass
&& (flags
& ECF_MALLOC
))
2441 if (pass
== 0 && crtl
->stack_protect_guard
)
2442 stack_protect_epilogue ();
2444 adjusted_args_size
= args_size
;
2445 /* Compute the actual size of the argument block required. The variable
2446 and constant sizes must be combined, the size may have to be rounded,
2447 and there may be a minimum required size. When generating a sibcall
2448 pattern, do not round up, since we'll be re-using whatever space our
2450 unadjusted_args_size
2451 = compute_argument_block_size (reg_parm_stack_space
,
2452 &adjusted_args_size
,
2455 : preferred_stack_boundary
));
2457 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2459 /* The argument block when performing a sibling call is the
2460 incoming argument block. */
2463 argblock
= crtl
->args
.internal_arg_pointer
;
2465 #ifdef STACK_GROWS_DOWNWARD
2466 = plus_constant (argblock
, crtl
->args
.pretend_args_size
);
2468 = plus_constant (argblock
, -crtl
->args
.pretend_args_size
);
2470 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2471 sbitmap_zero (stored_args_map
);
2474 /* If we have no actual push instructions, or shouldn't use them,
2475 make space for all args right now. */
2476 else if (adjusted_args_size
.var
!= 0)
2478 if (old_stack_level
== 0)
2480 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
2481 old_stack_pointer_delta
= stack_pointer_delta
;
2482 old_pending_adj
= pending_stack_adjust
;
2483 pending_stack_adjust
= 0;
2484 /* stack_arg_under_construction says whether a stack arg is
2485 being constructed at the old stack level. Pushing the stack
2486 gets a clean outgoing argument block. */
2487 old_stack_arg_under_construction
= stack_arg_under_construction
;
2488 stack_arg_under_construction
= 0;
2490 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2494 /* Note that we must go through the motions of allocating an argument
2495 block even if the size is zero because we may be storing args
2496 in the area reserved for register arguments, which may be part of
2499 int needed
= adjusted_args_size
.constant
;
2501 /* Store the maximum argument space used. It will be pushed by
2502 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2505 if (needed
> crtl
->outgoing_args_size
)
2506 crtl
->outgoing_args_size
= needed
;
2508 if (must_preallocate
)
2510 if (ACCUMULATE_OUTGOING_ARGS
)
2512 /* Since the stack pointer will never be pushed, it is
2513 possible for the evaluation of a parm to clobber
2514 something we have already written to the stack.
2515 Since most function calls on RISC machines do not use
2516 the stack, this is uncommon, but must work correctly.
2518 Therefore, we save any area of the stack that was already
2519 written and that we are using. Here we set up to do this
2520 by making a new stack usage map from the old one. The
2521 actual save will be done by store_one_arg.
2523 Another approach might be to try to reorder the argument
2524 evaluations to avoid this conflicting stack usage. */
2526 /* Since we will be writing into the entire argument area,
2527 the map must be allocated for its entire size, not just
2528 the part that is the responsibility of the caller. */
2529 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2530 needed
+= reg_parm_stack_space
;
2532 #ifdef ARGS_GROW_DOWNWARD
2533 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2536 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2539 if (stack_usage_map_buf
)
2540 free (stack_usage_map_buf
);
2541 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
2542 stack_usage_map
= stack_usage_map_buf
;
2544 if (initial_highest_arg_in_use
)
2545 memcpy (stack_usage_map
, initial_stack_usage_map
,
2546 initial_highest_arg_in_use
);
2548 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2549 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2550 (highest_outgoing_arg_in_use
2551 - initial_highest_arg_in_use
));
2554 /* The address of the outgoing argument list must not be
2555 copied to a register here, because argblock would be left
2556 pointing to the wrong place after the call to
2557 allocate_dynamic_stack_space below. */
2559 argblock
= virtual_outgoing_args_rtx
;
2563 if (inhibit_defer_pop
== 0)
2565 /* Try to reuse some or all of the pending_stack_adjust
2566 to get this space. */
2568 = (combine_pending_stack_adjustment_and_call
2569 (unadjusted_args_size
,
2570 &adjusted_args_size
,
2571 preferred_unit_stack_boundary
));
2573 /* combine_pending_stack_adjustment_and_call computes
2574 an adjustment before the arguments are allocated.
2575 Account for them and see whether or not the stack
2576 needs to go up or down. */
2577 needed
= unadjusted_args_size
- needed
;
2581 /* We're releasing stack space. */
2582 /* ??? We can avoid any adjustment at all if we're
2583 already aligned. FIXME. */
2584 pending_stack_adjust
= -needed
;
2585 do_pending_stack_adjust ();
2589 /* We need to allocate space. We'll do that in
2590 push_block below. */
2591 pending_stack_adjust
= 0;
2594 /* Special case this because overhead of `push_block' in
2595 this case is non-trivial. */
2597 argblock
= virtual_outgoing_args_rtx
;
2600 argblock
= push_block (GEN_INT (needed
), 0, 0);
2601 #ifdef ARGS_GROW_DOWNWARD
2602 argblock
= plus_constant (argblock
, needed
);
2606 /* We only really need to call `copy_to_reg' in the case
2607 where push insns are going to be used to pass ARGBLOCK
2608 to a function call in ARGS. In that case, the stack
2609 pointer changes value from the allocation point to the
2610 call point, and hence the value of
2611 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2612 as well always do it. */
2613 argblock
= copy_to_reg (argblock
);
2618 if (ACCUMULATE_OUTGOING_ARGS
)
2620 /* The save/restore code in store_one_arg handles all
2621 cases except one: a constructor call (including a C
2622 function returning a BLKmode struct) to initialize
2624 if (stack_arg_under_construction
)
2627 = GEN_INT (adjusted_args_size
.constant
2628 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
2629 : TREE_TYPE (fndecl
))) ? 0
2630 : reg_parm_stack_space
));
2631 if (old_stack_level
== 0)
2633 emit_stack_save (SAVE_BLOCK
, &old_stack_level
,
2635 old_stack_pointer_delta
= stack_pointer_delta
;
2636 old_pending_adj
= pending_stack_adjust
;
2637 pending_stack_adjust
= 0;
2638 /* stack_arg_under_construction says whether a stack
2639 arg is being constructed at the old stack level.
2640 Pushing the stack gets a clean outgoing argument
2642 old_stack_arg_under_construction
2643 = stack_arg_under_construction
;
2644 stack_arg_under_construction
= 0;
2645 /* Make a new map for the new argument list. */
2646 if (stack_usage_map_buf
)
2647 free (stack_usage_map_buf
);
2648 stack_usage_map_buf
= XCNEWVEC (char, highest_outgoing_arg_in_use
);
2649 stack_usage_map
= stack_usage_map_buf
;
2650 highest_outgoing_arg_in_use
= 0;
2652 allocate_dynamic_stack_space (push_size
, NULL_RTX
,
2656 /* If argument evaluation might modify the stack pointer,
2657 copy the address of the argument list to a register. */
2658 for (i
= 0; i
< num_actuals
; i
++)
2659 if (args
[i
].pass_on_stack
)
2661 argblock
= copy_addr_to_reg (argblock
);
2666 compute_argument_addresses (args
, argblock
, num_actuals
);
2668 /* If we push args individually in reverse order, perform stack alignment
2669 before the first push (the last arg). */
2670 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2671 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2673 /* When the stack adjustment is pending, we get better code
2674 by combining the adjustments. */
2675 if (pending_stack_adjust
2676 && ! inhibit_defer_pop
)
2678 pending_stack_adjust
2679 = (combine_pending_stack_adjustment_and_call
2680 (unadjusted_args_size
,
2681 &adjusted_args_size
,
2682 preferred_unit_stack_boundary
));
2683 do_pending_stack_adjust ();
2685 else if (argblock
== 0)
2686 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2687 - unadjusted_args_size
));
2689 /* Now that the stack is properly aligned, pops can't safely
2690 be deferred during the evaluation of the arguments. */
2693 funexp
= rtx_for_function_call (fndecl
, addr
);
2695 /* Figure out the register where the value, if any, will come back. */
2697 if (TYPE_MODE (rettype
) != VOIDmode
2698 && ! structure_value_addr
)
2700 if (pcc_struct_value
)
2701 valreg
= hard_function_value (build_pointer_type (rettype
),
2702 fndecl
, NULL
, (pass
== 0));
2704 valreg
= hard_function_value (rettype
, fndecl
, fntype
,
2707 /* If VALREG is a PARALLEL whose first member has a zero
2708 offset, use that. This is for targets such as m68k that
2709 return the same value in multiple places. */
2710 if (GET_CODE (valreg
) == PARALLEL
)
2712 rtx elem
= XVECEXP (valreg
, 0, 0);
2713 rtx where
= XEXP (elem
, 0);
2714 rtx offset
= XEXP (elem
, 1);
2715 if (offset
== const0_rtx
2716 && GET_MODE (where
) == GET_MODE (valreg
))
2721 /* Precompute all register parameters. It isn't safe to compute anything
2722 once we have started filling any specific hard regs. */
2723 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2725 if (CALL_EXPR_STATIC_CHAIN (exp
))
2726 static_chain_value
= expand_normal (CALL_EXPR_STATIC_CHAIN (exp
));
2728 static_chain_value
= 0;
2730 #ifdef REG_PARM_STACK_SPACE
2731 /* Save the fixed argument area if it's part of the caller's frame and
2732 is clobbered by argument setup for this call. */
2733 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2734 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2735 &low_to_save
, &high_to_save
);
2738 /* Now store (and compute if necessary) all non-register parms.
2739 These come before register parms, since they can require block-moves,
2740 which could clobber the registers used for register parms.
2741 Parms which have partial registers are not stored here,
2742 but we do preallocate space here if they want that. */
2744 for (i
= 0; i
< num_actuals
; i
++)
2746 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2748 rtx before_arg
= get_last_insn ();
2750 if (store_one_arg (&args
[i
], argblock
, flags
,
2751 adjusted_args_size
.var
!= 0,
2752 reg_parm_stack_space
)
2754 && check_sibcall_argument_overlap (before_arg
,
2756 sibcall_failure
= 1;
2759 if (((flags
& ECF_CONST
)
2760 || ((flags
& ECF_PURE
) && ACCUMULATE_OUTGOING_ARGS
))
2762 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
2763 gen_rtx_USE (VOIDmode
,
2768 /* If we have a parm that is passed in registers but not in memory
2769 and whose alignment does not permit a direct copy into registers,
2770 make a group of pseudos that correspond to each register that we
2772 if (STRICT_ALIGNMENT
)
2773 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2775 /* Now store any partially-in-registers parm.
2776 This is the last place a block-move can happen. */
2778 for (i
= 0; i
< num_actuals
; i
++)
2779 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2781 rtx before_arg
= get_last_insn ();
2783 if (store_one_arg (&args
[i
], argblock
, flags
,
2784 adjusted_args_size
.var
!= 0,
2785 reg_parm_stack_space
)
2787 && check_sibcall_argument_overlap (before_arg
,
2789 sibcall_failure
= 1;
2792 /* If we pushed args in forward order, perform stack alignment
2793 after pushing the last arg. */
2794 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
2795 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2796 - unadjusted_args_size
));
2798 /* If register arguments require space on the stack and stack space
2799 was not preallocated, allocate stack space here for arguments
2800 passed in registers. */
2801 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
2802 && !ACCUMULATE_OUTGOING_ARGS
2803 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
2804 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
2806 /* Pass the function the address in which to return a
2808 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
2810 structure_value_addr
2811 = convert_memory_address (Pmode
, structure_value_addr
);
2812 emit_move_insn (struct_value
,
2814 force_operand (structure_value_addr
,
2817 if (REG_P (struct_value
))
2818 use_reg (&call_fusage
, struct_value
);
2821 after_args
= get_last_insn ();
2822 funexp
= prepare_call_address (fndecl
, funexp
, static_chain_value
,
2823 &call_fusage
, reg_parm_seen
, pass
== 0);
2825 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
2826 pass
== 0, &sibcall_failure
);
2828 /* Save a pointer to the last insn before the call, so that we can
2829 later safely search backwards to find the CALL_INSN. */
2830 before_call
= get_last_insn ();
2832 /* Set up next argument register. For sibling calls on machines
2833 with register windows this should be the incoming register. */
2835 next_arg_reg
= targetm
.calls
.function_incoming_arg (&args_so_far
,
2840 next_arg_reg
= targetm
.calls
.function_arg (&args_so_far
,
2841 VOIDmode
, void_type_node
,
2844 /* All arguments and registers used for the call must be set up by
2847 /* Stack must be properly aligned now. */
2849 || !(stack_pointer_delta
% preferred_unit_stack_boundary
));
2851 /* Generate the actual call instruction. */
2852 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
2853 adjusted_args_size
.constant
, struct_value_size
,
2854 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
2855 flags
, & args_so_far
);
2857 /* If the call setup or the call itself overlaps with anything
2858 of the argument setup we probably clobbered our call address.
2859 In that case we can't do sibcalls. */
2861 && check_sibcall_argument_overlap (after_args
, 0, 0))
2862 sibcall_failure
= 1;
2864 /* If a non-BLKmode value is returned at the most significant end
2865 of a register, shift the register right by the appropriate amount
2866 and update VALREG accordingly. BLKmode values are handled by the
2867 group load/store machinery below. */
2868 if (!structure_value_addr
2869 && !pcc_struct_value
2870 && TYPE_MODE (rettype
) != BLKmode
2871 && targetm
.calls
.return_in_msb (rettype
))
2873 if (shift_return_value (TYPE_MODE (rettype
), false, valreg
))
2874 sibcall_failure
= 1;
2875 valreg
= gen_rtx_REG (TYPE_MODE (rettype
), REGNO (valreg
));
2878 if (pass
&& (flags
& ECF_MALLOC
))
2880 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2883 /* The return value from a malloc-like function is a pointer. */
2884 if (TREE_CODE (rettype
) == POINTER_TYPE
)
2885 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
2887 emit_move_insn (temp
, valreg
);
2889 /* The return value from a malloc-like function can not alias
2891 last
= get_last_insn ();
2892 add_reg_note (last
, REG_NOALIAS
, temp
);
2894 /* Write out the sequence. */
2895 insns
= get_insns ();
2901 /* For calls to `setjmp', etc., inform
2902 function.c:setjmp_warnings that it should complain if
2903 nonvolatile values are live. For functions that cannot
2904 return, inform flow that control does not fall through. */
2906 if ((flags
& ECF_NORETURN
) || pass
== 0)
2908 /* The barrier must be emitted
2909 immediately after the CALL_INSN. Some ports emit more
2910 than just a CALL_INSN above, so we must search for it here. */
2912 rtx last
= get_last_insn ();
2913 while (!CALL_P (last
))
2915 last
= PREV_INSN (last
);
2916 /* There was no CALL_INSN? */
2917 gcc_assert (last
!= before_call
);
2920 emit_barrier_after (last
);
2922 /* Stack adjustments after a noreturn call are dead code.
2923 However when NO_DEFER_POP is in effect, we must preserve
2924 stack_pointer_delta. */
2925 if (inhibit_defer_pop
== 0)
2927 stack_pointer_delta
= old_stack_allocated
;
2928 pending_stack_adjust
= 0;
2932 /* If value type not void, return an rtx for the value. */
2934 if (TYPE_MODE (rettype
) == VOIDmode
2936 target
= const0_rtx
;
2937 else if (structure_value_addr
)
2939 if (target
== 0 || !MEM_P (target
))
2942 = gen_rtx_MEM (TYPE_MODE (rettype
),
2943 memory_address (TYPE_MODE (rettype
),
2944 structure_value_addr
));
2945 set_mem_attributes (target
, rettype
, 1);
2948 else if (pcc_struct_value
)
2950 /* This is the special C++ case where we need to
2951 know what the true target was. We take care to
2952 never use this value more than once in one expression. */
2953 target
= gen_rtx_MEM (TYPE_MODE (rettype
),
2954 copy_to_reg (valreg
));
2955 set_mem_attributes (target
, rettype
, 1);
2957 /* Handle calls that return values in multiple non-contiguous locations.
2958 The Irix 6 ABI has examples of this. */
2959 else if (GET_CODE (valreg
) == PARALLEL
)
2963 /* This will only be assigned once, so it can be readonly. */
2964 tree nt
= build_qualified_type (rettype
,
2965 (TYPE_QUALS (rettype
)
2966 | TYPE_QUAL_CONST
));
2968 target
= assign_temp (nt
, 0, 1, 1);
2971 if (! rtx_equal_p (target
, valreg
))
2972 emit_group_store (target
, valreg
, rettype
,
2973 int_size_in_bytes (rettype
));
2975 /* We can not support sibling calls for this case. */
2976 sibcall_failure
= 1;
2979 && GET_MODE (target
) == TYPE_MODE (rettype
)
2980 && GET_MODE (target
) == GET_MODE (valreg
))
2982 bool may_overlap
= false;
2984 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
2985 reg to a plain register. */
2986 if (!REG_P (target
) || HARD_REGISTER_P (target
))
2987 valreg
= avoid_likely_spilled_reg (valreg
);
2989 /* If TARGET is a MEM in the argument area, and we have
2990 saved part of the argument area, then we can't store
2991 directly into TARGET as it may get overwritten when we
2992 restore the argument save area below. Don't work too
2993 hard though and simply force TARGET to a register if it
2994 is a MEM; the optimizer is quite likely to sort it out. */
2995 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
2996 for (i
= 0; i
< num_actuals
; i
++)
2997 if (args
[i
].save_area
)
3004 target
= copy_to_reg (valreg
);
3007 /* TARGET and VALREG cannot be equal at this point
3008 because the latter would not have
3009 REG_FUNCTION_VALUE_P true, while the former would if
3010 it were referring to the same register.
3012 If they refer to the same register, this move will be
3013 a no-op, except when function inlining is being
3015 emit_move_insn (target
, valreg
);
3017 /* If we are setting a MEM, this code must be executed.
3018 Since it is emitted after the call insn, sibcall
3019 optimization cannot be performed in that case. */
3021 sibcall_failure
= 1;
3024 else if (TYPE_MODE (rettype
) == BLKmode
)
3027 if (GET_MODE (val
) != BLKmode
)
3028 val
= avoid_likely_spilled_reg (val
);
3029 target
= copy_blkmode_from_reg (target
, val
, rettype
);
3031 /* We can not support sibling calls for this case. */
3032 sibcall_failure
= 1;
3035 target
= copy_to_reg (avoid_likely_spilled_reg (valreg
));
3037 /* If we promoted this return value, make the proper SUBREG.
3038 TARGET might be const0_rtx here, so be careful. */
3040 && TYPE_MODE (rettype
) != BLKmode
3041 && GET_MODE (target
) != TYPE_MODE (rettype
))
3043 tree type
= rettype
;
3044 int unsignedp
= TYPE_UNSIGNED (type
);
3046 enum machine_mode pmode
;
3048 /* Ensure we promote as expected, and get the new unsignedness. */
3049 pmode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
3051 gcc_assert (GET_MODE (target
) == pmode
);
3053 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
3054 && (GET_MODE_SIZE (GET_MODE (target
))
3055 > GET_MODE_SIZE (TYPE_MODE (type
))))
3057 offset
= GET_MODE_SIZE (GET_MODE (target
))
3058 - GET_MODE_SIZE (TYPE_MODE (type
));
3059 if (! BYTES_BIG_ENDIAN
)
3060 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
3061 else if (! WORDS_BIG_ENDIAN
)
3062 offset
%= UNITS_PER_WORD
;
3065 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
3066 SUBREG_PROMOTED_VAR_P (target
) = 1;
3067 SUBREG_PROMOTED_UNSIGNED_SET (target
, unsignedp
);
3070 /* If size of args is variable or this was a constructor call for a stack
3071 argument, restore saved stack-pointer value. */
3073 if (old_stack_level
)
3075 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
3076 stack_pointer_delta
= old_stack_pointer_delta
;
3077 pending_stack_adjust
= old_pending_adj
;
3078 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
3079 stack_arg_under_construction
= old_stack_arg_under_construction
;
3080 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3081 stack_usage_map
= initial_stack_usage_map
;
3082 sibcall_failure
= 1;
3084 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
3086 #ifdef REG_PARM_STACK_SPACE
3088 restore_fixed_argument_area (save_area
, argblock
,
3089 high_to_save
, low_to_save
);
3092 /* If we saved any argument areas, restore them. */
3093 for (i
= 0; i
< num_actuals
; i
++)
3094 if (args
[i
].save_area
)
3096 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
3098 = gen_rtx_MEM (save_mode
,
3099 memory_address (save_mode
,
3100 XEXP (args
[i
].stack_slot
, 0)));
3102 if (save_mode
!= BLKmode
)
3103 emit_move_insn (stack_area
, args
[i
].save_area
);
3105 emit_block_move (stack_area
, args
[i
].save_area
,
3106 GEN_INT (args
[i
].locate
.size
.constant
),
3107 BLOCK_OP_CALL_PARM
);
3110 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3111 stack_usage_map
= initial_stack_usage_map
;
3114 /* If this was alloca, record the new stack level for nonlocal gotos.
3115 Check for the handler slots since we might not have a save area
3116 for non-local gotos. */
3118 if ((flags
& ECF_MAY_BE_ALLOCA
) && cfun
->nonlocal_goto_save_area
!= 0)
3119 update_nonlocal_goto_save_area ();
3121 /* Free up storage we no longer need. */
3122 for (i
= 0; i
< num_actuals
; ++i
)
3123 if (args
[i
].aligned_regs
)
3124 free (args
[i
].aligned_regs
);
3126 insns
= get_insns ();
3131 tail_call_insns
= insns
;
3133 /* Restore the pending stack adjustment now that we have
3134 finished generating the sibling call sequence. */
3136 pending_stack_adjust
= save_pending_stack_adjust
;
3137 stack_pointer_delta
= save_stack_pointer_delta
;
3139 /* Prepare arg structure for next iteration. */
3140 for (i
= 0; i
< num_actuals
; i
++)
3143 args
[i
].aligned_regs
= 0;
3147 sbitmap_free (stored_args_map
);
3151 normal_call_insns
= insns
;
3153 /* Verify that we've deallocated all the stack we used. */
3154 gcc_assert ((flags
& ECF_NORETURN
)
3155 || (old_stack_allocated
3156 == stack_pointer_delta
- pending_stack_adjust
));
3159 /* If something prevents making this a sibling call,
3160 zero out the sequence. */
3161 if (sibcall_failure
)
3162 tail_call_insns
= NULL_RTX
;
3167 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3168 arguments too, as argument area is now clobbered by the call. */
3169 if (tail_call_insns
)
3171 emit_insn (tail_call_insns
);
3172 crtl
->tail_call_emit
= true;
3175 emit_insn (normal_call_insns
);
3177 currently_expanding_call
--;
3179 if (stack_usage_map_buf
)
3180 free (stack_usage_map_buf
);
3185 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3186 this function's incoming arguments.
3188 At the start of RTL generation we know the only REG_EQUIV notes
3189 in the rtl chain are those for incoming arguments, so we can look
3190 for REG_EQUIV notes between the start of the function and the
3191 NOTE_INSN_FUNCTION_BEG.
3193 This is (slight) overkill. We could keep track of the highest
3194 argument we clobber and be more selective in removing notes, but it
3195 does not seem to be worth the effort. */
3198 fixup_tail_calls (void)
3202 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
3206 /* There are never REG_EQUIV notes for the incoming arguments
3207 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3209 && NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
)
3212 note
= find_reg_note (insn
, REG_EQUIV
, 0);
3214 remove_note (insn
, note
);
3215 note
= find_reg_note (insn
, REG_EQUIV
, 0);
3220 /* Traverse a list of TYPES and expand all complex types into their
3223 split_complex_types (tree types
)
3227 /* Before allocating memory, check for the common case of no complex. */
3228 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3230 tree type
= TREE_VALUE (p
);
3231 if (TREE_CODE (type
) == COMPLEX_TYPE
3232 && targetm
.calls
.split_complex_arg (type
))
3238 types
= copy_list (types
);
3240 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3242 tree complex_type
= TREE_VALUE (p
);
3244 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
3245 && targetm
.calls
.split_complex_arg (complex_type
))
3249 /* Rewrite complex type with component type. */
3250 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
3251 next
= TREE_CHAIN (p
);
3253 /* Add another component type for the imaginary part. */
3254 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
3255 TREE_CHAIN (p
) = imag
;
3256 TREE_CHAIN (imag
) = next
;
3258 /* Skip the newly created node. */
3266 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3267 The RETVAL parameter specifies whether return value needs to be saved, other
3268 parameters are documented in the emit_library_call function below. */
3271 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
3272 enum libcall_type fn_type
,
3273 enum machine_mode outmode
, int nargs
, va_list p
)
3275 /* Total size in bytes of all the stack-parms scanned so far. */
3276 struct args_size args_size
;
3277 /* Size of arguments before any adjustments (such as rounding). */
3278 struct args_size original_args_size
;
3281 /* Todo, choose the correct decl type of orgfun. Sadly this information
3282 isn't present here, so we default to native calling abi here. */
3283 tree fndecl ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
3284 tree fntype ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
3288 CUMULATIVE_ARGS args_so_far
;
3292 enum machine_mode mode
;
3295 struct locate_and_pad_arg_data locate
;
3299 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3300 rtx call_fusage
= 0;
3303 int pcc_struct_value
= 0;
3304 int struct_value_size
= 0;
3306 int reg_parm_stack_space
= 0;
3309 tree tfom
; /* type_for_mode (outmode, 0) */
3311 #ifdef REG_PARM_STACK_SPACE
3312 /* Define the boundary of the register parm stack space that needs to be
3314 int low_to_save
= 0, high_to_save
= 0;
3315 rtx save_area
= 0; /* Place that it is saved. */
3318 /* Size of the stack reserved for parameter registers. */
3319 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3320 char *initial_stack_usage_map
= stack_usage_map
;
3321 char *stack_usage_map_buf
= NULL
;
3323 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
3325 #ifdef REG_PARM_STACK_SPACE
3326 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3329 /* By default, library functions can not throw. */
3330 flags
= ECF_NOTHROW
;
3343 flags
|= ECF_NORETURN
;
3346 flags
= ECF_NORETURN
;
3348 case LCT_RETURNS_TWICE
:
3349 flags
= ECF_RETURNS_TWICE
;
3354 /* Ensure current function's preferred stack boundary is at least
3356 if (crtl
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3357 crtl
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3359 /* If this kind of value comes back in memory,
3360 decide where in memory it should come back. */
3361 if (outmode
!= VOIDmode
)
3363 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
3364 if (aggregate_value_p (tfom
, 0))
3366 #ifdef PCC_STATIC_STRUCT_RETURN
3368 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
3369 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3370 pcc_struct_value
= 1;
3372 value
= gen_reg_rtx (outmode
);
3373 #else /* not PCC_STATIC_STRUCT_RETURN */
3374 struct_value_size
= GET_MODE_SIZE (outmode
);
3375 if (value
!= 0 && MEM_P (value
))
3378 mem_value
= assign_temp (tfom
, 0, 1, 1);
3380 /* This call returns a big structure. */
3381 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
3385 tfom
= void_type_node
;
3387 /* ??? Unfinished: must pass the memory address as an argument. */
3389 /* Copy all the libcall-arguments out of the varargs data
3390 and into a vector ARGVEC.
3392 Compute how to pass each argument. We only support a very small subset
3393 of the full argument passing conventions to limit complexity here since
3394 library functions shouldn't have many args. */
3396 argvec
= XALLOCAVEC (struct arg
, nargs
+ 1);
3397 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3399 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3400 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3402 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0, nargs
);
3405 args_size
.constant
= 0;
3412 /* If there's a structure value address to be passed,
3413 either pass it in the special place, or pass it as an extra argument. */
3414 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
3416 rtx addr
= XEXP (mem_value
, 0);
3420 /* Make sure it is a reasonable operand for a move or push insn. */
3421 if (!REG_P (addr
) && !MEM_P (addr
)
3422 && ! (CONSTANT_P (addr
) && LEGITIMATE_CONSTANT_P (addr
)))
3423 addr
= force_operand (addr
, NULL_RTX
);
3425 argvec
[count
].value
= addr
;
3426 argvec
[count
].mode
= Pmode
;
3427 argvec
[count
].partial
= 0;
3429 argvec
[count
].reg
= targetm
.calls
.function_arg (&args_so_far
,
3430 Pmode
, NULL_TREE
, true);
3431 gcc_assert (targetm
.calls
.arg_partial_bytes (&args_so_far
, Pmode
,
3432 NULL_TREE
, 1) == 0);
3434 locate_and_pad_parm (Pmode
, NULL_TREE
,
3435 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3438 argvec
[count
].reg
!= 0,
3440 0, NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3442 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3443 || reg_parm_stack_space
> 0)
3444 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3446 targetm
.calls
.function_arg_advance (&args_so_far
, Pmode
, (tree
) 0, true);
3451 for (; count
< nargs
; count
++)
3453 rtx val
= va_arg (p
, rtx
);
3454 enum machine_mode mode
= (enum machine_mode
) va_arg (p
, int);
3456 /* We cannot convert the arg value to the mode the library wants here;
3457 must do it earlier where we know the signedness of the arg. */
3458 gcc_assert (mode
!= BLKmode
3459 && (GET_MODE (val
) == mode
|| GET_MODE (val
) == VOIDmode
));
3461 /* Make sure it is a reasonable operand for a move or push insn. */
3462 if (!REG_P (val
) && !MEM_P (val
)
3463 && ! (CONSTANT_P (val
) && LEGITIMATE_CONSTANT_P (val
)))
3464 val
= force_operand (val
, NULL_RTX
);
3466 if (pass_by_reference (&args_so_far
, mode
, NULL_TREE
, 1))
3470 = !reference_callee_copied (&args_so_far
, mode
, NULL_TREE
, 1);
3472 /* If this was a CONST function, it is now PURE since it now
3474 if (flags
& ECF_CONST
)
3476 flags
&= ~ECF_CONST
;
3480 if (MEM_P (val
) && !must_copy
)
3484 slot
= assign_temp (lang_hooks
.types
.type_for_mode (mode
, 0),
3486 emit_move_insn (slot
, val
);
3489 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3490 gen_rtx_USE (VOIDmode
, slot
),
3493 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3494 gen_rtx_CLOBBER (VOIDmode
,
3499 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3502 argvec
[count
].value
= val
;
3503 argvec
[count
].mode
= mode
;
3505 argvec
[count
].reg
= targetm
.calls
.function_arg (&args_so_far
, mode
,
3508 argvec
[count
].partial
3509 = targetm
.calls
.arg_partial_bytes (&args_so_far
, mode
, NULL_TREE
, 1);
3511 locate_and_pad_parm (mode
, NULL_TREE
,
3512 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3515 argvec
[count
].reg
!= 0,
3517 argvec
[count
].partial
,
3518 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3520 gcc_assert (!argvec
[count
].locate
.size
.var
);
3522 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3523 || reg_parm_stack_space
> 0)
3524 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3526 targetm
.calls
.function_arg_advance (&args_so_far
, mode
, (tree
) 0, true);
3529 /* If this machine requires an external definition for library
3530 functions, write one out. */
3531 assemble_external_libcall (fun
);
3533 original_args_size
= args_size
;
3534 args_size
.constant
= (((args_size
.constant
3535 + stack_pointer_delta
3539 - stack_pointer_delta
);
3541 args_size
.constant
= MAX (args_size
.constant
,
3542 reg_parm_stack_space
);
3544 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3545 args_size
.constant
-= reg_parm_stack_space
;
3547 if (args_size
.constant
> crtl
->outgoing_args_size
)
3548 crtl
->outgoing_args_size
= args_size
.constant
;
3550 if (ACCUMULATE_OUTGOING_ARGS
)
3552 /* Since the stack pointer will never be pushed, it is possible for
3553 the evaluation of a parm to clobber something we have already
3554 written to the stack. Since most function calls on RISC machines
3555 do not use the stack, this is uncommon, but must work correctly.
3557 Therefore, we save any area of the stack that was already written
3558 and that we are using. Here we set up to do this by making a new
3559 stack usage map from the old one.
3561 Another approach might be to try to reorder the argument
3562 evaluations to avoid this conflicting stack usage. */
3564 needed
= args_size
.constant
;
3566 /* Since we will be writing into the entire argument area, the
3567 map must be allocated for its entire size, not just the part that
3568 is the responsibility of the caller. */
3569 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3570 needed
+= reg_parm_stack_space
;
3572 #ifdef ARGS_GROW_DOWNWARD
3573 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3576 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3579 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
3580 stack_usage_map
= stack_usage_map_buf
;
3582 if (initial_highest_arg_in_use
)
3583 memcpy (stack_usage_map
, initial_stack_usage_map
,
3584 initial_highest_arg_in_use
);
3586 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3587 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3588 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3591 /* We must be careful to use virtual regs before they're instantiated,
3592 and real regs afterwards. Loop optimization, for example, can create
3593 new libcalls after we've instantiated the virtual regs, and if we
3594 use virtuals anyway, they won't match the rtl patterns. */
3596 if (virtuals_instantiated
)
3597 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3599 argblock
= virtual_outgoing_args_rtx
;
3604 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3607 /* If we push args individually in reverse order, perform stack alignment
3608 before the first push (the last arg). */
3609 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3610 anti_adjust_stack (GEN_INT (args_size
.constant
3611 - original_args_size
.constant
));
3613 if (PUSH_ARGS_REVERSED
)
3624 #ifdef REG_PARM_STACK_SPACE
3625 if (ACCUMULATE_OUTGOING_ARGS
)
3627 /* The argument list is the property of the called routine and it
3628 may clobber it. If the fixed area has been used for previous
3629 parameters, we must save and restore it. */
3630 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
3631 &low_to_save
, &high_to_save
);
3635 /* Push the args that need to be pushed. */
3637 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3638 are to be pushed. */
3639 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3641 enum machine_mode mode
= argvec
[argnum
].mode
;
3642 rtx val
= argvec
[argnum
].value
;
3643 rtx reg
= argvec
[argnum
].reg
;
3644 int partial
= argvec
[argnum
].partial
;
3645 unsigned int parm_align
= argvec
[argnum
].locate
.boundary
;
3646 int lower_bound
= 0, upper_bound
= 0, i
;
3648 if (! (reg
!= 0 && partial
== 0))
3650 if (ACCUMULATE_OUTGOING_ARGS
)
3652 /* If this is being stored into a pre-allocated, fixed-size,
3653 stack area, save any previous data at that location. */
3655 #ifdef ARGS_GROW_DOWNWARD
3656 /* stack_slot is negative, but we want to index stack_usage_map
3657 with positive values. */
3658 upper_bound
= -argvec
[argnum
].locate
.slot_offset
.constant
+ 1;
3659 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
3661 lower_bound
= argvec
[argnum
].locate
.slot_offset
.constant
;
3662 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
3666 /* Don't worry about things in the fixed argument area;
3667 it has already been saved. */
3668 if (i
< reg_parm_stack_space
)
3669 i
= reg_parm_stack_space
;
3670 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
3673 if (i
< upper_bound
)
3675 /* We need to make a save area. */
3677 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
3678 enum machine_mode save_mode
3679 = mode_for_size (size
, MODE_INT
, 1);
3681 = plus_constant (argblock
,
3682 argvec
[argnum
].locate
.offset
.constant
);
3684 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
3686 if (save_mode
== BLKmode
)
3688 argvec
[argnum
].save_area
3689 = assign_stack_temp (BLKmode
,
3690 argvec
[argnum
].locate
.size
.constant
,
3693 emit_block_move (validize_mem (argvec
[argnum
].save_area
),
3695 GEN_INT (argvec
[argnum
].locate
.size
.constant
),
3696 BLOCK_OP_CALL_PARM
);
3700 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3702 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3707 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, parm_align
,
3708 partial
, reg
, 0, argblock
,
3709 GEN_INT (argvec
[argnum
].locate
.offset
.constant
),
3710 reg_parm_stack_space
,
3711 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
));
3713 /* Now mark the segment we just used. */
3714 if (ACCUMULATE_OUTGOING_ARGS
)
3715 for (i
= lower_bound
; i
< upper_bound
; i
++)
3716 stack_usage_map
[i
] = 1;
3720 if ((flags
& ECF_CONST
)
3721 || ((flags
& ECF_PURE
) && ACCUMULATE_OUTGOING_ARGS
))
3725 /* Indicate argument access so that alias.c knows that these
3728 use
= plus_constant (argblock
,
3729 argvec
[argnum
].locate
.offset
.constant
);
3731 /* When arguments are pushed, trying to tell alias.c where
3732 exactly this argument is won't work, because the
3733 auto-increment causes confusion. So we merely indicate
3734 that we access something with a known mode somewhere on
3736 use
= gen_rtx_PLUS (Pmode
, virtual_outgoing_args_rtx
,
3737 gen_rtx_SCRATCH (Pmode
));
3738 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
3739 use
= gen_rtx_USE (VOIDmode
, use
);
3740 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
3745 /* If we pushed args in forward order, perform stack alignment
3746 after pushing the last arg. */
3747 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3748 anti_adjust_stack (GEN_INT (args_size
.constant
3749 - original_args_size
.constant
));
3751 if (PUSH_ARGS_REVERSED
)
3756 fun
= prepare_call_address (NULL
, fun
, NULL
, &call_fusage
, 0, 0);
3758 /* Now load any reg parms into their regs. */
3760 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3761 are to be pushed. */
3762 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3764 enum machine_mode mode
= argvec
[argnum
].mode
;
3765 rtx val
= argvec
[argnum
].value
;
3766 rtx reg
= argvec
[argnum
].reg
;
3767 int partial
= argvec
[argnum
].partial
;
3769 /* Handle calls that pass values in multiple non-contiguous
3770 locations. The PA64 has examples of this for library calls. */
3771 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3772 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
3773 else if (reg
!= 0 && partial
== 0)
3774 emit_move_insn (reg
, val
);
3779 /* Any regs containing parms remain in use through the call. */
3780 for (count
= 0; count
< nargs
; count
++)
3782 rtx reg
= argvec
[count
].reg
;
3783 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3784 use_group_regs (&call_fusage
, reg
);
3787 int partial
= argvec
[count
].partial
;
3791 gcc_assert (partial
% UNITS_PER_WORD
== 0);
3792 nregs
= partial
/ UNITS_PER_WORD
;
3793 use_regs (&call_fusage
, REGNO (reg
), nregs
);
3796 use_reg (&call_fusage
, reg
);
3800 /* Pass the function the address in which to return a structure value. */
3801 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
3803 emit_move_insn (struct_value
,
3805 force_operand (XEXP (mem_value
, 0),
3807 if (REG_P (struct_value
))
3808 use_reg (&call_fusage
, struct_value
);
3811 /* Don't allow popping to be deferred, since then
3812 cse'ing of library calls could delete a call and leave the pop. */
3814 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
3815 ? hard_libcall_value (outmode
, orgfun
) : NULL_RTX
);
3817 /* Stack must be properly aligned now. */
3818 gcc_assert (!(stack_pointer_delta
3819 & (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1)));
3821 before_call
= get_last_insn ();
3823 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3824 will set inhibit_defer_pop to that value. */
3825 /* The return type is needed to decide how many bytes the function pops.
3826 Signedness plays no role in that, so for simplicity, we pretend it's
3827 always signed. We also assume that the list of arguments passed has
3828 no impact, so we pretend it is unknown. */
3830 emit_call_1 (fun
, NULL
,
3831 get_identifier (XSTR (orgfun
, 0)),
3832 build_function_type (tfom
, NULL_TREE
),
3833 original_args_size
.constant
, args_size
.constant
,
3835 targetm
.calls
.function_arg (&args_so_far
,
3836 VOIDmode
, void_type_node
, true),
3838 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, & args_so_far
);
3840 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
3841 that it should complain if nonvolatile values are live. For
3842 functions that cannot return, inform flow that control does not
3845 if (flags
& ECF_NORETURN
)
3847 /* The barrier note must be emitted
3848 immediately after the CALL_INSN. Some ports emit more than
3849 just a CALL_INSN above, so we must search for it here. */
3851 rtx last
= get_last_insn ();
3852 while (!CALL_P (last
))
3854 last
= PREV_INSN (last
);
3855 /* There was no CALL_INSN? */
3856 gcc_assert (last
!= before_call
);
3859 emit_barrier_after (last
);
3862 /* Now restore inhibit_defer_pop to its actual original value. */
3867 /* Copy the value to the right place. */
3868 if (outmode
!= VOIDmode
&& retval
)
3874 if (value
!= mem_value
)
3875 emit_move_insn (value
, mem_value
);
3877 else if (GET_CODE (valreg
) == PARALLEL
)
3880 value
= gen_reg_rtx (outmode
);
3881 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
3885 /* Convert to the proper mode if a promotion has been active. */
3886 if (GET_MODE (valreg
) != outmode
)
3888 int unsignedp
= TYPE_UNSIGNED (tfom
);
3890 gcc_assert (promote_function_mode (tfom
, outmode
, &unsignedp
,
3891 fndecl
? TREE_TYPE (fndecl
) : fntype
, 1)
3892 == GET_MODE (valreg
));
3893 valreg
= convert_modes (outmode
, GET_MODE (valreg
), valreg
, 0);
3897 emit_move_insn (value
, valreg
);
3903 if (ACCUMULATE_OUTGOING_ARGS
)
3905 #ifdef REG_PARM_STACK_SPACE
3907 restore_fixed_argument_area (save_area
, argblock
,
3908 high_to_save
, low_to_save
);
3911 /* If we saved any argument areas, restore them. */
3912 for (count
= 0; count
< nargs
; count
++)
3913 if (argvec
[count
].save_area
)
3915 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
3916 rtx adr
= plus_constant (argblock
,
3917 argvec
[count
].locate
.offset
.constant
);
3918 rtx stack_area
= gen_rtx_MEM (save_mode
,
3919 memory_address (save_mode
, adr
));
3921 if (save_mode
== BLKmode
)
3922 emit_block_move (stack_area
,
3923 validize_mem (argvec
[count
].save_area
),
3924 GEN_INT (argvec
[count
].locate
.size
.constant
),
3925 BLOCK_OP_CALL_PARM
);
3927 emit_move_insn (stack_area
, argvec
[count
].save_area
);
3930 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3931 stack_usage_map
= initial_stack_usage_map
;
3934 if (stack_usage_map_buf
)
3935 free (stack_usage_map_buf
);
3941 /* Output a library call to function FUN (a SYMBOL_REF rtx)
3942 (emitting the queue unless NO_QUEUE is nonzero),
3943 for a value of mode OUTMODE,
3944 with NARGS different arguments, passed as alternating rtx values
3945 and machine_modes to convert them to.
3947 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
3948 `const' calls, LCT_PURE for `pure' calls, or other LCT_ value for
3949 other types of library calls. */
3952 emit_library_call (rtx orgfun
, enum libcall_type fn_type
,
3953 enum machine_mode outmode
, int nargs
, ...)
3957 va_start (p
, nargs
);
3958 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
3962 /* Like emit_library_call except that an extra argument, VALUE,
3963 comes second and says where to store the result.
3964 (If VALUE is zero, this function chooses a convenient way
3965 to return the value.
3967 This function returns an rtx for where the value is to be found.
3968 If VALUE is nonzero, VALUE is returned. */
3971 emit_library_call_value (rtx orgfun
, rtx value
,
3972 enum libcall_type fn_type
,
3973 enum machine_mode outmode
, int nargs
, ...)
3978 va_start (p
, nargs
);
3979 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
3986 /* Store a single argument for a function call
3987 into the register or memory area where it must be passed.
3988 *ARG describes the argument value and where to pass it.
3990 ARGBLOCK is the address of the stack-block for all the arguments,
3991 or 0 on a machine where arguments are pushed individually.
3993 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
3994 so must be careful about how the stack is used.
3996 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
3997 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
3998 that we need not worry about saving and restoring the stack.
4000 FNDECL is the declaration of the function we are calling.
4002 Return nonzero if this arg should cause sibcall failure,
4006 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
4007 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
4009 tree pval
= arg
->tree_value
;
4013 int i
, lower_bound
= 0, upper_bound
= 0;
4014 int sibcall_failure
= 0;
4016 if (TREE_CODE (pval
) == ERROR_MARK
)
4019 /* Push a new temporary level for any temporaries we make for
4023 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4025 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4026 save any previous data at that location. */
4027 if (argblock
&& ! variable_size
&& arg
->stack
)
4029 #ifdef ARGS_GROW_DOWNWARD
4030 /* stack_slot is negative, but we want to index stack_usage_map
4031 with positive values. */
4032 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4033 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4037 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
4039 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4040 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4044 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
4048 /* Don't worry about things in the fixed argument area;
4049 it has already been saved. */
4050 if (i
< reg_parm_stack_space
)
4051 i
= reg_parm_stack_space
;
4052 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
4055 if (i
< upper_bound
)
4057 /* We need to make a save area. */
4058 unsigned int size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
4059 enum machine_mode save_mode
= mode_for_size (size
, MODE_INT
, 1);
4060 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
4061 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
4063 if (save_mode
== BLKmode
)
4065 tree ot
= TREE_TYPE (arg
->tree_value
);
4066 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4067 | TYPE_QUAL_CONST
));
4069 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4070 preserve_temp_slots (arg
->save_area
);
4071 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4072 GEN_INT (arg
->locate
.size
.constant
),
4073 BLOCK_OP_CALL_PARM
);
4077 arg
->save_area
= gen_reg_rtx (save_mode
);
4078 emit_move_insn (arg
->save_area
, stack_area
);
4084 /* If this isn't going to be placed on both the stack and in registers,
4085 set up the register and number of words. */
4086 if (! arg
->pass_on_stack
)
4088 if (flags
& ECF_SIBCALL
)
4089 reg
= arg
->tail_call_reg
;
4092 partial
= arg
->partial
;
4095 /* Being passed entirely in a register. We shouldn't be called in
4097 gcc_assert (reg
== 0 || partial
!= 0);
4099 /* If this arg needs special alignment, don't load the registers
4101 if (arg
->n_aligned_regs
!= 0)
4104 /* If this is being passed partially in a register, we can't evaluate
4105 it directly into its stack slot. Otherwise, we can. */
4106 if (arg
->value
== 0)
4108 /* stack_arg_under_construction is nonzero if a function argument is
4109 being evaluated directly into the outgoing argument list and
4110 expand_call must take special action to preserve the argument list
4111 if it is called recursively.
4113 For scalar function arguments stack_usage_map is sufficient to
4114 determine which stack slots must be saved and restored. Scalar
4115 arguments in general have pass_on_stack == 0.
4117 If this argument is initialized by a function which takes the
4118 address of the argument (a C++ constructor or a C function
4119 returning a BLKmode structure), then stack_usage_map is
4120 insufficient and expand_call must push the stack around the
4121 function call. Such arguments have pass_on_stack == 1.
4123 Note that it is always safe to set stack_arg_under_construction,
4124 but this generates suboptimal code if set when not needed. */
4126 if (arg
->pass_on_stack
)
4127 stack_arg_under_construction
++;
4129 arg
->value
= expand_expr (pval
,
4131 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4132 ? NULL_RTX
: arg
->stack
,
4133 VOIDmode
, EXPAND_STACK_PARM
);
4135 /* If we are promoting object (or for any other reason) the mode
4136 doesn't agree, convert the mode. */
4138 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4139 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4140 arg
->value
, arg
->unsignedp
);
4142 if (arg
->pass_on_stack
)
4143 stack_arg_under_construction
--;
4146 /* Check for overlap with already clobbered argument area. */
4147 if ((flags
& ECF_SIBCALL
)
4148 && MEM_P (arg
->value
)
4149 && mem_overlaps_already_clobbered_arg_p (XEXP (arg
->value
, 0),
4150 arg
->locate
.size
.constant
))
4151 sibcall_failure
= 1;
4153 /* Don't allow anything left on stack from computation
4154 of argument to alloca. */
4155 if (flags
& ECF_MAY_BE_ALLOCA
)
4156 do_pending_stack_adjust ();
4158 if (arg
->value
== arg
->stack
)
4159 /* If the value is already in the stack slot, we are done. */
4161 else if (arg
->mode
!= BLKmode
)
4164 unsigned int parm_align
;
4166 /* Argument is a scalar, not entirely passed in registers.
4167 (If part is passed in registers, arg->partial says how much
4168 and emit_push_insn will take care of putting it there.)
4170 Push it, and if its size is less than the
4171 amount of space allocated to it,
4172 also bump stack pointer by the additional space.
4173 Note that in C the default argument promotions
4174 will prevent such mismatches. */
4176 size
= GET_MODE_SIZE (arg
->mode
);
4177 /* Compute how much space the push instruction will push.
4178 On many machines, pushing a byte will advance the stack
4179 pointer by a halfword. */
4180 #ifdef PUSH_ROUNDING
4181 size
= PUSH_ROUNDING (size
);
4185 /* Compute how much space the argument should get:
4186 round up to a multiple of the alignment for arguments. */
4187 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4188 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4189 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4190 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4192 /* Compute the alignment of the pushed argument. */
4193 parm_align
= arg
->locate
.boundary
;
4194 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4196 int pad
= used
- size
;
4199 unsigned int pad_align
= (pad
& -pad
) * BITS_PER_UNIT
;
4200 parm_align
= MIN (parm_align
, pad_align
);
4204 /* This isn't already where we want it on the stack, so put it there.
4205 This can either be done with push or copy insns. */
4206 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
,
4207 parm_align
, partial
, reg
, used
- size
, argblock
,
4208 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4209 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4211 /* Unless this is a partially-in-register argument, the argument is now
4214 arg
->value
= arg
->stack
;
4218 /* BLKmode, at least partly to be pushed. */
4220 unsigned int parm_align
;
4224 /* Pushing a nonscalar.
4225 If part is passed in registers, PARTIAL says how much
4226 and emit_push_insn will take care of putting it there. */
4228 /* Round its size up to a multiple
4229 of the allocation unit for arguments. */
4231 if (arg
->locate
.size
.var
!= 0)
4234 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
4238 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4239 for BLKmode is careful to avoid it. */
4240 excess
= (arg
->locate
.size
.constant
4241 - int_size_in_bytes (TREE_TYPE (pval
))
4243 size_rtx
= expand_expr (size_in_bytes (TREE_TYPE (pval
)),
4244 NULL_RTX
, TYPE_MODE (sizetype
),
4248 parm_align
= arg
->locate
.boundary
;
4250 /* When an argument is padded down, the block is aligned to
4251 PARM_BOUNDARY, but the actual argument isn't. */
4252 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4254 if (arg
->locate
.size
.var
)
4255 parm_align
= BITS_PER_UNIT
;
4258 unsigned int excess_align
= (excess
& -excess
) * BITS_PER_UNIT
;
4259 parm_align
= MIN (parm_align
, excess_align
);
4263 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
4265 /* emit_push_insn might not work properly if arg->value and
4266 argblock + arg->locate.offset areas overlap. */
4270 if (XEXP (x
, 0) == crtl
->args
.internal_arg_pointer
4271 || (GET_CODE (XEXP (x
, 0)) == PLUS
4272 && XEXP (XEXP (x
, 0), 0) ==
4273 crtl
->args
.internal_arg_pointer
4274 && CONST_INT_P (XEXP (XEXP (x
, 0), 1))))
4276 if (XEXP (x
, 0) != crtl
->args
.internal_arg_pointer
)
4277 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4279 /* expand_call should ensure this. */
4280 gcc_assert (!arg
->locate
.offset
.var
4281 && arg
->locate
.size
.var
== 0
4282 && CONST_INT_P (size_rtx
));
4284 if (arg
->locate
.offset
.constant
> i
)
4286 if (arg
->locate
.offset
.constant
< i
+ INTVAL (size_rtx
))
4287 sibcall_failure
= 1;
4289 else if (arg
->locate
.offset
.constant
< i
)
4291 /* Use arg->locate.size.constant instead of size_rtx
4292 because we only care about the part of the argument
4294 if (i
< (arg
->locate
.offset
.constant
4295 + arg
->locate
.size
.constant
))
4296 sibcall_failure
= 1;
4300 /* Even though they appear to be at the same location,
4301 if part of the outgoing argument is in registers,
4302 they aren't really at the same location. Check for
4303 this by making sure that the incoming size is the
4304 same as the outgoing size. */
4305 if (arg
->locate
.size
.constant
!= INTVAL (size_rtx
))
4306 sibcall_failure
= 1;
4311 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4312 parm_align
, partial
, reg
, excess
, argblock
,
4313 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4314 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4316 /* Unless this is a partially-in-register argument, the argument is now
4319 ??? Unlike the case above, in which we want the actual
4320 address of the data, so that we can load it directly into a
4321 register, here we want the address of the stack slot, so that
4322 it's properly aligned for word-by-word copying or something
4323 like that. It's not clear that this is always correct. */
4325 arg
->value
= arg
->stack_slot
;
4328 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
4330 tree type
= TREE_TYPE (arg
->tree_value
);
4332 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
4333 int_size_in_bytes (type
));
4336 /* Mark all slots this store used. */
4337 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
4338 && argblock
&& ! variable_size
&& arg
->stack
)
4339 for (i
= lower_bound
; i
< upper_bound
; i
++)
4340 stack_usage_map
[i
] = 1;
4342 /* Once we have pushed something, pops can't safely
4343 be deferred during the rest of the arguments. */
4346 /* Free any temporary slots made in processing this argument. Show
4347 that we might have taken the address of something and pushed that
4349 preserve_temp_slots (NULL_RTX
);
4353 return sibcall_failure
;
4356 /* Nonzero if we do not know how to pass TYPE solely in registers. */
4359 must_pass_in_stack_var_size (enum machine_mode mode ATTRIBUTE_UNUSED
,
4365 /* If the type has variable size... */
4366 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4369 /* If the type is marked as addressable (it is required
4370 to be constructed into the stack)... */
4371 if (TREE_ADDRESSABLE (type
))
4377 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
4378 takes trailing padding of a structure into account. */
4379 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
4382 must_pass_in_stack_var_size_or_pad (enum machine_mode mode
, const_tree type
)
4387 /* If the type has variable size... */
4388 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4391 /* If the type is marked as addressable (it is required
4392 to be constructed into the stack)... */
4393 if (TREE_ADDRESSABLE (type
))
4396 /* If the padding and mode of the type is such that a copy into
4397 a register would put it into the wrong part of the register. */
4399 && int_size_in_bytes (type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
4400 && (FUNCTION_ARG_PADDING (mode
, type
)
4401 == (BYTES_BIG_ENDIAN
? upward
: downward
)))