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
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"
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
= ((SMALL_REGISTER_CLASSES
&& reg_parm_seen
)
179 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
180 : memory_address (FUNCTION_MODE
, funexp
));
183 #ifndef NO_FUNCTION_CSE
184 if (optimize
&& ! flag_no_function_cse
)
185 funexp
= force_reg (Pmode
, funexp
);
189 if (static_chain_value
!= 0)
194 chain
= targetm
.calls
.static_chain (fndecl
, false);
195 static_chain_value
= convert_memory_address (Pmode
, static_chain_value
);
197 emit_move_insn (chain
, static_chain_value
);
199 use_reg (call_fusage
, chain
);
205 /* Generate instructions to call function FUNEXP,
206 and optionally pop the results.
207 The CALL_INSN is the first insn generated.
209 FNDECL is the declaration node of the function. This is given to the
210 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
212 FUNTYPE is the data type of the function. This is given to the macro
213 RETURN_POPS_ARGS to determine whether this function pops its own args.
214 We used to allow an identifier for library functions, but that doesn't
215 work when the return type is an aggregate type and the calling convention
216 says that the pointer to this aggregate is to be popped by the callee.
218 STACK_SIZE is the number of bytes of arguments on the stack,
219 ROUNDED_STACK_SIZE is that number rounded up to
220 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
221 both to put into the call insn and to generate explicit popping
224 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
225 It is zero if this call doesn't want a structure value.
227 NEXT_ARG_REG is the rtx that results from executing
228 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
229 just after all the args have had their registers assigned.
230 This could be whatever you like, but normally it is the first
231 arg-register beyond those used for args in this call,
232 or 0 if all the arg-registers are used in this call.
233 It is passed on to `gen_call' so you can put this info in the call insn.
235 VALREG is a hard register in which a value is returned,
236 or 0 if the call does not return a value.
238 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
239 the args to this call were processed.
240 We restore `inhibit_defer_pop' to that value.
242 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
243 denote registers used by the called function. */
246 emit_call_1 (rtx funexp
, tree fntree ATTRIBUTE_UNUSED
, tree fndecl ATTRIBUTE_UNUSED
,
247 tree funtype ATTRIBUTE_UNUSED
,
248 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED
,
249 HOST_WIDE_INT rounded_stack_size
,
250 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED
,
251 rtx next_arg_reg ATTRIBUTE_UNUSED
, rtx valreg
,
252 int old_inhibit_defer_pop
, rtx call_fusage
, int ecf_flags
,
253 CUMULATIVE_ARGS
*args_so_far ATTRIBUTE_UNUSED
)
255 rtx rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
257 int already_popped
= 0;
258 HOST_WIDE_INT n_popped
= RETURN_POPS_ARGS (fndecl
, funtype
, stack_size
);
259 #if defined (HAVE_call) && defined (HAVE_call_value)
260 rtx struct_value_size_rtx
;
261 struct_value_size_rtx
= GEN_INT (struct_value_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 struct_value_size_rtx
));
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 struct_value_size_rtx
));
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 ())
718 && ((SMALL_REGISTER_CLASSES
&& *reg_parm_seen
)
720 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
724 #ifdef REG_PARM_STACK_SPACE
726 /* The argument list is the property of the called routine and it
727 may clobber it. If the fixed area has been used for previous
728 parameters, we must save and restore it. */
731 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
736 /* Compute the boundary of the area that needs to be saved, if any. */
737 high
= reg_parm_stack_space
;
738 #ifdef ARGS_GROW_DOWNWARD
741 if (high
> highest_outgoing_arg_in_use
)
742 high
= highest_outgoing_arg_in_use
;
744 for (low
= 0; low
< high
; low
++)
745 if (stack_usage_map
[low
] != 0)
748 enum machine_mode save_mode
;
753 while (stack_usage_map
[--high
] == 0)
757 *high_to_save
= high
;
759 num_to_save
= high
- low
+ 1;
760 save_mode
= mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
762 /* If we don't have the required alignment, must do this
764 if ((low
& (MIN (GET_MODE_SIZE (save_mode
),
765 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
768 #ifdef ARGS_GROW_DOWNWARD
773 stack_area
= gen_rtx_MEM (save_mode
,
774 memory_address (save_mode
,
775 plus_constant (argblock
,
778 set_mem_align (stack_area
, PARM_BOUNDARY
);
779 if (save_mode
== BLKmode
)
781 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
782 emit_block_move (validize_mem (save_area
), stack_area
,
783 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
787 save_area
= gen_reg_rtx (save_mode
);
788 emit_move_insn (save_area
, stack_area
);
798 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
800 enum machine_mode save_mode
= GET_MODE (save_area
);
804 #ifdef ARGS_GROW_DOWNWARD
805 delta
= -high_to_save
;
809 stack_area
= gen_rtx_MEM (save_mode
,
810 memory_address (save_mode
,
811 plus_constant (argblock
, delta
)));
812 set_mem_align (stack_area
, PARM_BOUNDARY
);
814 if (save_mode
!= BLKmode
)
815 emit_move_insn (stack_area
, save_area
);
817 emit_block_move (stack_area
, validize_mem (save_area
),
818 GEN_INT (high_to_save
- low_to_save
+ 1),
821 #endif /* REG_PARM_STACK_SPACE */
823 /* If any elements in ARGS refer to parameters that are to be passed in
824 registers, but not in memory, and whose alignment does not permit a
825 direct copy into registers. Copy the values into a group of pseudos
826 which we will later copy into the appropriate hard registers.
828 Pseudos for each unaligned argument will be stored into the array
829 args[argnum].aligned_regs. The caller is responsible for deallocating
830 the aligned_regs array if it is nonzero. */
833 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
837 for (i
= 0; i
< num_actuals
; i
++)
838 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
839 && args
[i
].mode
== BLKmode
840 && MEM_P (args
[i
].value
)
841 && (MEM_ALIGN (args
[i
].value
)
842 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
844 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
845 int endian_correction
= 0;
849 gcc_assert (args
[i
].partial
% UNITS_PER_WORD
== 0);
850 args
[i
].n_aligned_regs
= args
[i
].partial
/ UNITS_PER_WORD
;
854 args
[i
].n_aligned_regs
855 = (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
858 args
[i
].aligned_regs
= XNEWVEC (rtx
, args
[i
].n_aligned_regs
);
860 /* Structures smaller than a word are normally aligned to the
861 least significant byte. On a BYTES_BIG_ENDIAN machine,
862 this means we must skip the empty high order bytes when
863 calculating the bit offset. */
864 if (bytes
< UNITS_PER_WORD
865 #ifdef BLOCK_REG_PADDING
866 && (BLOCK_REG_PADDING (args
[i
].mode
,
867 TREE_TYPE (args
[i
].tree_value
), 1)
873 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
875 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
877 rtx reg
= gen_reg_rtx (word_mode
);
878 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
879 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
881 args
[i
].aligned_regs
[j
] = reg
;
882 word
= extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
883 word_mode
, word_mode
);
885 /* There is no need to restrict this code to loading items
886 in TYPE_ALIGN sized hunks. The bitfield instructions can
887 load up entire word sized registers efficiently.
889 ??? This may not be needed anymore.
890 We use to emit a clobber here but that doesn't let later
891 passes optimize the instructions we emit. By storing 0 into
892 the register later passes know the first AND to zero out the
893 bitfield being set in the register is unnecessary. The store
894 of 0 will be deleted as will at least the first AND. */
896 emit_move_insn (reg
, const0_rtx
);
898 bytes
-= bitsize
/ BITS_PER_UNIT
;
899 store_bit_field (reg
, bitsize
, endian_correction
, word_mode
,
905 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
908 NUM_ACTUALS is the total number of parameters.
910 N_NAMED_ARGS is the total number of named arguments.
912 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
915 FNDECL is the tree code for the target of this call (if known)
917 ARGS_SO_FAR holds state needed by the target to know where to place
920 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
921 for arguments which are passed in registers.
923 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
924 and may be modified by this routine.
926 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
927 flags which may may be modified by this routine.
929 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
930 that requires allocation of stack space.
932 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
933 the thunked-to function. */
936 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
937 struct arg_data
*args
,
938 struct args_size
*args_size
,
939 int n_named_args ATTRIBUTE_UNUSED
,
940 tree exp
, tree struct_value_addr_value
,
941 tree fndecl
, tree fntype
,
942 CUMULATIVE_ARGS
*args_so_far
,
943 int reg_parm_stack_space
,
944 rtx
*old_stack_level
, int *old_pending_adj
,
945 int *must_preallocate
, int *ecf_flags
,
946 bool *may_tailcall
, bool call_from_thunk_p
)
948 location_t loc
= EXPR_LOCATION (exp
);
949 /* 1 if scanning parms front to back, -1 if scanning back to front. */
952 /* Count arg position in order args appear. */
957 args_size
->constant
= 0;
960 /* In this loop, we consider args in the order they are written.
961 We fill up ARGS from the front or from the back if necessary
962 so that in any case the first arg to be pushed ends up at the front. */
964 if (PUSH_ARGS_REVERSED
)
966 i
= num_actuals
- 1, inc
= -1;
967 /* In this case, must reverse order of args
968 so that we compute and push the last arg first. */
975 /* First fill in the actual arguments in the ARGS array, splitting
976 complex arguments if necessary. */
979 call_expr_arg_iterator iter
;
982 if (struct_value_addr_value
)
984 args
[j
].tree_value
= struct_value_addr_value
;
987 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
989 tree argtype
= TREE_TYPE (arg
);
990 if (targetm
.calls
.split_complex_arg
992 && TREE_CODE (argtype
) == COMPLEX_TYPE
993 && targetm
.calls
.split_complex_arg (argtype
))
995 tree subtype
= TREE_TYPE (argtype
);
996 args
[j
].tree_value
= build1 (REALPART_EXPR
, subtype
, arg
);
998 args
[j
].tree_value
= build1 (IMAGPART_EXPR
, subtype
, arg
);
1001 args
[j
].tree_value
= arg
;
1006 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1007 for (argpos
= 0; argpos
< num_actuals
; i
+= inc
, argpos
++)
1009 tree type
= TREE_TYPE (args
[i
].tree_value
);
1011 enum machine_mode mode
;
1013 /* Replace erroneous argument with constant zero. */
1014 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1015 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1017 /* If TYPE is a transparent union, pass things the way we would
1018 pass the first field of the union. We have already verified that
1019 the modes are the same. */
1020 if (TREE_CODE (type
) == UNION_TYPE
&& TYPE_TRANSPARENT_UNION (type
))
1021 type
= TREE_TYPE (TYPE_FIELDS (type
));
1023 /* Decide where to pass this arg.
1025 args[i].reg is nonzero if all or part is passed in registers.
1027 args[i].partial is nonzero if part but not all is passed in registers,
1028 and the exact value says how many bytes are passed in registers.
1030 args[i].pass_on_stack is nonzero if the argument must at least be
1031 computed on the stack. It may then be loaded back into registers
1032 if args[i].reg is nonzero.
1034 These decisions are driven by the FUNCTION_... macros and must agree
1035 with those made by function.c. */
1037 /* See if this argument should be passed by invisible reference. */
1038 if (pass_by_reference (args_so_far
, TYPE_MODE (type
),
1039 type
, argpos
< n_named_args
))
1045 = reference_callee_copied (args_so_far
, TYPE_MODE (type
),
1046 type
, argpos
< n_named_args
);
1048 /* If we're compiling a thunk, pass through invisible references
1049 instead of making a copy. */
1050 if (call_from_thunk_p
1052 && !TREE_ADDRESSABLE (type
)
1053 && (base
= get_base_address (args
[i
].tree_value
))
1054 && TREE_CODE (base
) != SSA_NAME
1055 && (!DECL_P (base
) || MEM_P (DECL_RTL (base
)))))
1057 /* We can't use sibcalls if a callee-copied argument is
1058 stored in the current function's frame. */
1059 if (!call_from_thunk_p
&& DECL_P (base
) && !TREE_STATIC (base
))
1060 *may_tailcall
= false;
1062 args
[i
].tree_value
= build_fold_addr_expr_loc (loc
,
1063 args
[i
].tree_value
);
1064 type
= TREE_TYPE (args
[i
].tree_value
);
1066 if (*ecf_flags
& ECF_CONST
)
1067 *ecf_flags
&= ~(ECF_CONST
| ECF_LOOPING_CONST_OR_PURE
);
1071 /* We make a copy of the object and pass the address to the
1072 function being called. */
1075 if (!COMPLETE_TYPE_P (type
)
1076 || TREE_CODE (TYPE_SIZE_UNIT (type
)) != INTEGER_CST
1077 || (flag_stack_check
== GENERIC_STACK_CHECK
1078 && compare_tree_int (TYPE_SIZE_UNIT (type
),
1079 STACK_CHECK_MAX_VAR_SIZE
) > 0))
1081 /* This is a variable-sized object. Make space on the stack
1083 rtx size_rtx
= expr_size (args
[i
].tree_value
);
1085 if (*old_stack_level
== 0)
1087 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1088 *old_pending_adj
= pending_stack_adjust
;
1089 pending_stack_adjust
= 0;
1092 copy
= gen_rtx_MEM (BLKmode
,
1093 allocate_dynamic_stack_space
1094 (size_rtx
, NULL_RTX
, TYPE_ALIGN (type
)));
1095 set_mem_attributes (copy
, type
, 1);
1098 copy
= assign_temp (type
, 0, 1, 0);
1100 store_expr (args
[i
].tree_value
, copy
, 0, false);
1102 /* Just change the const function to pure and then let
1103 the next test clear the pure based on
1105 if (*ecf_flags
& ECF_CONST
)
1107 *ecf_flags
&= ~ECF_CONST
;
1108 *ecf_flags
|= ECF_PURE
;
1111 if (!callee_copies
&& *ecf_flags
& ECF_PURE
)
1112 *ecf_flags
&= ~(ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
1115 = build_fold_addr_expr_loc (loc
, make_tree (type
, copy
));
1116 type
= TREE_TYPE (args
[i
].tree_value
);
1117 *may_tailcall
= false;
1121 unsignedp
= TYPE_UNSIGNED (type
);
1122 mode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
1123 fndecl
? TREE_TYPE (fndecl
) : fntype
, 0);
1125 args
[i
].unsignedp
= unsignedp
;
1126 args
[i
].mode
= mode
;
1128 args
[i
].reg
= FUNCTION_ARG (*args_so_far
, mode
, type
,
1129 argpos
< n_named_args
);
1130 #ifdef FUNCTION_INCOMING_ARG
1131 /* If this is a sibling call and the machine has register windows, the
1132 register window has to be unwinded before calling the routine, so
1133 arguments have to go into the incoming registers. */
1134 args
[i
].tail_call_reg
= FUNCTION_INCOMING_ARG (*args_so_far
, mode
, type
,
1135 argpos
< n_named_args
);
1137 args
[i
].tail_call_reg
= args
[i
].reg
;
1142 = targetm
.calls
.arg_partial_bytes (args_so_far
, mode
, type
,
1143 argpos
< n_named_args
);
1145 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (mode
, type
);
1147 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1148 it means that we are to pass this arg in the register(s) designated
1149 by the PARALLEL, but also to pass it in the stack. */
1150 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1151 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1152 args
[i
].pass_on_stack
= 1;
1154 /* If this is an addressable type, we must preallocate the stack
1155 since we must evaluate the object into its final location.
1157 If this is to be passed in both registers and the stack, it is simpler
1159 if (TREE_ADDRESSABLE (type
)
1160 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1161 *must_preallocate
= 1;
1163 /* Compute the stack-size of this argument. */
1164 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1165 || reg_parm_stack_space
> 0
1166 || args
[i
].pass_on_stack
)
1167 locate_and_pad_parm (mode
, type
,
1168 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1173 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
1174 fndecl
, args_size
, &args
[i
].locate
);
1175 #ifdef BLOCK_REG_PADDING
1177 /* The argument is passed entirely in registers. See at which
1178 end it should be padded. */
1179 args
[i
].locate
.where_pad
=
1180 BLOCK_REG_PADDING (mode
, type
,
1181 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
1184 /* Update ARGS_SIZE, the total stack space for args so far. */
1186 args_size
->constant
+= args
[i
].locate
.size
.constant
;
1187 if (args
[i
].locate
.size
.var
)
1188 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
1190 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1191 have been used, etc. */
1193 FUNCTION_ARG_ADVANCE (*args_so_far
, TYPE_MODE (type
), type
,
1194 argpos
< n_named_args
);
1198 /* Update ARGS_SIZE to contain the total size for the argument block.
1199 Return the original constant component of the argument block's size.
1201 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1202 for arguments passed in registers. */
1205 compute_argument_block_size (int reg_parm_stack_space
,
1206 struct args_size
*args_size
,
1207 tree fndecl ATTRIBUTE_UNUSED
,
1208 tree fntype ATTRIBUTE_UNUSED
,
1209 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
1211 int unadjusted_args_size
= args_size
->constant
;
1213 /* For accumulate outgoing args mode we don't need to align, since the frame
1214 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1215 backends from generating misaligned frame sizes. */
1216 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1217 preferred_stack_boundary
= STACK_BOUNDARY
;
1219 /* Compute the actual size of the argument block required. The variable
1220 and constant sizes must be combined, the size may have to be rounded,
1221 and there may be a minimum required size. */
1225 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1226 args_size
->constant
= 0;
1228 preferred_stack_boundary
/= BITS_PER_UNIT
;
1229 if (preferred_stack_boundary
> 1)
1231 /* We don't handle this case yet. To handle it correctly we have
1232 to add the delta, round and subtract the delta.
1233 Currently no machine description requires this support. */
1234 gcc_assert (!(stack_pointer_delta
& (preferred_stack_boundary
- 1)));
1235 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1238 if (reg_parm_stack_space
> 0)
1241 = size_binop (MAX_EXPR
, args_size
->var
,
1242 ssize_int (reg_parm_stack_space
));
1244 /* The area corresponding to register parameters is not to count in
1245 the size of the block we need. So make the adjustment. */
1246 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
1248 = size_binop (MINUS_EXPR
, args_size
->var
,
1249 ssize_int (reg_parm_stack_space
));
1254 preferred_stack_boundary
/= BITS_PER_UNIT
;
1255 if (preferred_stack_boundary
< 1)
1256 preferred_stack_boundary
= 1;
1257 args_size
->constant
= (((args_size
->constant
1258 + stack_pointer_delta
1259 + preferred_stack_boundary
- 1)
1260 / preferred_stack_boundary
1261 * preferred_stack_boundary
)
1262 - stack_pointer_delta
);
1264 args_size
->constant
= MAX (args_size
->constant
,
1265 reg_parm_stack_space
);
1267 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
1268 args_size
->constant
-= reg_parm_stack_space
;
1270 return unadjusted_args_size
;
1273 /* Precompute parameters as needed for a function call.
1275 FLAGS is mask of ECF_* constants.
1277 NUM_ACTUALS is the number of arguments.
1279 ARGS is an array containing information for each argument; this
1280 routine fills in the INITIAL_VALUE and VALUE fields for each
1281 precomputed argument. */
1284 precompute_arguments (int num_actuals
, struct arg_data
*args
)
1288 /* If this is a libcall, then precompute all arguments so that we do not
1289 get extraneous instructions emitted as part of the libcall sequence. */
1291 /* If we preallocated the stack space, and some arguments must be passed
1292 on the stack, then we must precompute any parameter which contains a
1293 function call which will store arguments on the stack.
1294 Otherwise, evaluating the parameter may clobber previous parameters
1295 which have already been stored into the stack. (we have code to avoid
1296 such case by saving the outgoing stack arguments, but it results in
1298 if (!ACCUMULATE_OUTGOING_ARGS
)
1301 for (i
= 0; i
< num_actuals
; i
++)
1304 enum machine_mode mode
;
1306 if (TREE_CODE (args
[i
].tree_value
) != CALL_EXPR
)
1309 /* If this is an addressable type, we cannot pre-evaluate it. */
1310 type
= TREE_TYPE (args
[i
].tree_value
);
1311 gcc_assert (!TREE_ADDRESSABLE (type
));
1313 args
[i
].initial_value
= args
[i
].value
1314 = expand_normal (args
[i
].tree_value
);
1316 mode
= TYPE_MODE (type
);
1317 if (mode
!= args
[i
].mode
)
1319 int unsignedp
= args
[i
].unsignedp
;
1321 = convert_modes (args
[i
].mode
, mode
,
1322 args
[i
].value
, args
[i
].unsignedp
);
1324 /* CSE will replace this only if it contains args[i].value
1325 pseudo, so convert it down to the declared mode using
1327 if (REG_P (args
[i
].value
)
1328 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
1329 && promote_mode (type
, mode
, &unsignedp
) != args
[i
].mode
)
1331 args
[i
].initial_value
1332 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1333 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1334 SUBREG_PROMOTED_UNSIGNED_SET (args
[i
].initial_value
,
1341 /* Given the current state of MUST_PREALLOCATE and information about
1342 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1343 compute and return the final value for MUST_PREALLOCATE. */
1346 finalize_must_preallocate (int must_preallocate
, int num_actuals
,
1347 struct arg_data
*args
, struct args_size
*args_size
)
1349 /* See if we have or want to preallocate stack space.
1351 If we would have to push a partially-in-regs parm
1352 before other stack parms, preallocate stack space instead.
1354 If the size of some parm is not a multiple of the required stack
1355 alignment, we must preallocate.
1357 If the total size of arguments that would otherwise create a copy in
1358 a temporary (such as a CALL) is more than half the total argument list
1359 size, preallocation is faster.
1361 Another reason to preallocate is if we have a machine (like the m88k)
1362 where stack alignment is required to be maintained between every
1363 pair of insns, not just when the call is made. However, we assume here
1364 that such machines either do not have push insns (and hence preallocation
1365 would occur anyway) or the problem is taken care of with
1368 if (! must_preallocate
)
1370 int partial_seen
= 0;
1371 int copy_to_evaluate_size
= 0;
1374 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1376 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1378 else if (partial_seen
&& args
[i
].reg
== 0)
1379 must_preallocate
= 1;
1381 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1382 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1383 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1384 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1385 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1386 copy_to_evaluate_size
1387 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1390 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1391 && args_size
->constant
> 0)
1392 must_preallocate
= 1;
1394 return must_preallocate
;
1397 /* If we preallocated stack space, compute the address of each argument
1398 and store it into the ARGS array.
1400 We need not ensure it is a valid memory address here; it will be
1401 validized when it is used.
1403 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1406 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
1410 rtx arg_reg
= argblock
;
1411 int i
, arg_offset
= 0;
1413 if (GET_CODE (argblock
) == PLUS
)
1414 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1416 for (i
= 0; i
< num_actuals
; i
++)
1418 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
1419 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
1421 unsigned int align
, boundary
;
1422 unsigned int units_on_stack
= 0;
1423 enum machine_mode partial_mode
= VOIDmode
;
1425 /* Skip this parm if it will not be passed on the stack. */
1426 if (! args
[i
].pass_on_stack
1428 && args
[i
].partial
== 0)
1431 if (CONST_INT_P (offset
))
1432 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1434 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1436 addr
= plus_constant (addr
, arg_offset
);
1438 if (args
[i
].partial
!= 0)
1440 /* Only part of the parameter is being passed on the stack.
1441 Generate a simple memory reference of the correct size. */
1442 units_on_stack
= args
[i
].locate
.size
.constant
;
1443 partial_mode
= mode_for_size (units_on_stack
* BITS_PER_UNIT
,
1445 args
[i
].stack
= gen_rtx_MEM (partial_mode
, addr
);
1446 set_mem_size (args
[i
].stack
, GEN_INT (units_on_stack
));
1450 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1451 set_mem_attributes (args
[i
].stack
,
1452 TREE_TYPE (args
[i
].tree_value
), 1);
1454 align
= BITS_PER_UNIT
;
1455 boundary
= args
[i
].locate
.boundary
;
1456 if (args
[i
].locate
.where_pad
!= downward
)
1458 else if (CONST_INT_P (offset
))
1460 align
= INTVAL (offset
) * BITS_PER_UNIT
| boundary
;
1461 align
= align
& -align
;
1463 set_mem_align (args
[i
].stack
, align
);
1465 if (CONST_INT_P (slot_offset
))
1466 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1468 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1470 addr
= plus_constant (addr
, arg_offset
);
1472 if (args
[i
].partial
!= 0)
1474 /* Only part of the parameter is being passed on the stack.
1475 Generate a simple memory reference of the correct size.
1477 args
[i
].stack_slot
= gen_rtx_MEM (partial_mode
, addr
);
1478 set_mem_size (args
[i
].stack_slot
, GEN_INT (units_on_stack
));
1482 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1483 set_mem_attributes (args
[i
].stack_slot
,
1484 TREE_TYPE (args
[i
].tree_value
), 1);
1486 set_mem_align (args
[i
].stack_slot
, args
[i
].locate
.boundary
);
1488 /* Function incoming arguments may overlap with sibling call
1489 outgoing arguments and we cannot allow reordering of reads
1490 from function arguments with stores to outgoing arguments
1491 of sibling calls. */
1492 set_mem_alias_set (args
[i
].stack
, 0);
1493 set_mem_alias_set (args
[i
].stack_slot
, 0);
1498 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1499 in a call instruction.
1501 FNDECL is the tree node for the target function. For an indirect call
1502 FNDECL will be NULL_TREE.
1504 ADDR is the operand 0 of CALL_EXPR for this call. */
1507 rtx_for_function_call (tree fndecl
, tree addr
)
1511 /* Get the function to call, in the form of RTL. */
1514 /* If this is the first use of the function, see if we need to
1515 make an external definition for it. */
1516 if (!TREE_USED (fndecl
) && fndecl
!= current_function_decl
)
1518 assemble_external (fndecl
);
1519 TREE_USED (fndecl
) = 1;
1522 /* Get a SYMBOL_REF rtx for the function address. */
1523 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1526 /* Generate an rtx (probably a pseudo-register) for the address. */
1529 funexp
= expand_normal (addr
);
1530 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1535 /* Return true if and only if SIZE storage units (usually bytes)
1536 starting from address ADDR overlap with already clobbered argument
1537 area. This function is used to determine if we should give up a
1541 mem_overlaps_already_clobbered_arg_p (rtx addr
, unsigned HOST_WIDE_INT size
)
1545 if (addr
== crtl
->args
.internal_arg_pointer
)
1547 else if (GET_CODE (addr
) == PLUS
1548 && XEXP (addr
, 0) == crtl
->args
.internal_arg_pointer
1549 && CONST_INT_P (XEXP (addr
, 1)))
1550 i
= INTVAL (XEXP (addr
, 1));
1551 /* Return true for arg pointer based indexed addressing. */
1552 else if (GET_CODE (addr
) == PLUS
1553 && (XEXP (addr
, 0) == crtl
->args
.internal_arg_pointer
1554 || XEXP (addr
, 1) == crtl
->args
.internal_arg_pointer
))
1559 #ifdef ARGS_GROW_DOWNWARD
1564 unsigned HOST_WIDE_INT k
;
1566 for (k
= 0; k
< size
; k
++)
1567 if (i
+ k
< stored_args_map
->n_bits
1568 && TEST_BIT (stored_args_map
, i
+ k
))
1575 /* Do the register loads required for any wholly-register parms or any
1576 parms which are passed both on the stack and in a register. Their
1577 expressions were already evaluated.
1579 Mark all register-parms as living through the call, putting these USE
1580 insns in the CALL_INSN_FUNCTION_USAGE field.
1582 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1583 checking, setting *SIBCALL_FAILURE if appropriate. */
1586 load_register_parameters (struct arg_data
*args
, int num_actuals
,
1587 rtx
*call_fusage
, int flags
, int is_sibcall
,
1588 int *sibcall_failure
)
1592 for (i
= 0; i
< num_actuals
; i
++)
1594 rtx reg
= ((flags
& ECF_SIBCALL
)
1595 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1598 int partial
= args
[i
].partial
;
1601 rtx before_arg
= get_last_insn ();
1602 /* Set non-negative if we must move a word at a time, even if
1603 just one word (e.g, partial == 4 && mode == DFmode). Set
1604 to -1 if we just use a normal move insn. This value can be
1605 zero if the argument is a zero size structure. */
1607 if (GET_CODE (reg
) == PARALLEL
)
1611 gcc_assert (partial
% UNITS_PER_WORD
== 0);
1612 nregs
= partial
/ UNITS_PER_WORD
;
1614 else if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
)
1616 size
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1617 nregs
= (size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1620 size
= GET_MODE_SIZE (args
[i
].mode
);
1622 /* Handle calls that pass values in multiple non-contiguous
1623 locations. The Irix 6 ABI has examples of this. */
1625 if (GET_CODE (reg
) == PARALLEL
)
1626 emit_group_move (reg
, args
[i
].parallel_value
);
1628 /* If simple case, just do move. If normal partial, store_one_arg
1629 has already loaded the register for us. In all other cases,
1630 load the register(s) from memory. */
1632 else if (nregs
== -1)
1634 emit_move_insn (reg
, args
[i
].value
);
1635 #ifdef BLOCK_REG_PADDING
1636 /* Handle case where we have a value that needs shifting
1637 up to the msb. eg. a QImode value and we're padding
1638 upward on a BYTES_BIG_ENDIAN machine. */
1639 if (size
< UNITS_PER_WORD
1640 && (args
[i
].locate
.where_pad
1641 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
1644 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1646 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1647 report the whole reg as used. Strictly speaking, the
1648 call only uses SIZE bytes at the msb end, but it doesn't
1649 seem worth generating rtl to say that. */
1650 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
1651 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
1652 build_int_cst (NULL_TREE
, shift
),
1655 emit_move_insn (reg
, x
);
1660 /* If we have pre-computed the values to put in the registers in
1661 the case of non-aligned structures, copy them in now. */
1663 else if (args
[i
].n_aligned_regs
!= 0)
1664 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1665 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1666 args
[i
].aligned_regs
[j
]);
1668 else if (partial
== 0 || args
[i
].pass_on_stack
)
1670 rtx mem
= validize_mem (args
[i
].value
);
1672 /* Check for overlap with already clobbered argument area. */
1674 && mem_overlaps_already_clobbered_arg_p (XEXP (args
[i
].value
, 0),
1676 *sibcall_failure
= 1;
1678 /* Handle a BLKmode that needs shifting. */
1679 if (nregs
== 1 && size
< UNITS_PER_WORD
1680 #ifdef BLOCK_REG_PADDING
1681 && args
[i
].locate
.where_pad
== downward
1687 rtx tem
= operand_subword_force (mem
, 0, args
[i
].mode
);
1688 rtx ri
= gen_rtx_REG (word_mode
, REGNO (reg
));
1689 rtx x
= gen_reg_rtx (word_mode
);
1690 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1691 enum tree_code dir
= BYTES_BIG_ENDIAN
? RSHIFT_EXPR
1694 emit_move_insn (x
, tem
);
1695 x
= expand_shift (dir
, word_mode
, x
,
1696 build_int_cst (NULL_TREE
, shift
),
1699 emit_move_insn (ri
, x
);
1702 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
1705 /* When a parameter is a block, and perhaps in other cases, it is
1706 possible that it did a load from an argument slot that was
1707 already clobbered. */
1709 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
1710 *sibcall_failure
= 1;
1712 /* Handle calls that pass values in multiple non-contiguous
1713 locations. The Irix 6 ABI has examples of this. */
1714 if (GET_CODE (reg
) == PARALLEL
)
1715 use_group_regs (call_fusage
, reg
);
1716 else if (nregs
== -1)
1717 use_reg (call_fusage
, reg
);
1719 use_regs (call_fusage
, REGNO (reg
), nregs
);
1724 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1725 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1726 bytes, then we would need to push some additional bytes to pad the
1727 arguments. So, we compute an adjust to the stack pointer for an
1728 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1729 bytes. Then, when the arguments are pushed the stack will be perfectly
1730 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1731 be popped after the call. Returns the adjustment. */
1734 combine_pending_stack_adjustment_and_call (int unadjusted_args_size
,
1735 struct args_size
*args_size
,
1736 unsigned int preferred_unit_stack_boundary
)
1738 /* The number of bytes to pop so that the stack will be
1739 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1740 HOST_WIDE_INT adjustment
;
1741 /* The alignment of the stack after the arguments are pushed, if we
1742 just pushed the arguments without adjust the stack here. */
1743 unsigned HOST_WIDE_INT unadjusted_alignment
;
1745 unadjusted_alignment
1746 = ((stack_pointer_delta
+ unadjusted_args_size
)
1747 % preferred_unit_stack_boundary
);
1749 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1750 as possible -- leaving just enough left to cancel out the
1751 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1752 PENDING_STACK_ADJUST is non-negative, and congruent to
1753 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1755 /* Begin by trying to pop all the bytes. */
1756 unadjusted_alignment
1757 = (unadjusted_alignment
1758 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1759 adjustment
= pending_stack_adjust
;
1760 /* Push enough additional bytes that the stack will be aligned
1761 after the arguments are pushed. */
1762 if (preferred_unit_stack_boundary
> 1)
1764 if (unadjusted_alignment
> 0)
1765 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1767 adjustment
+= unadjusted_alignment
;
1770 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1771 bytes after the call. The right number is the entire
1772 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1773 by the arguments in the first place. */
1775 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1780 /* Scan X expression if it does not dereference any argument slots
1781 we already clobbered by tail call arguments (as noted in stored_args_map
1783 Return nonzero if X expression dereferences such argument slots,
1787 check_sibcall_argument_overlap_1 (rtx x
)
1796 code
= GET_CODE (x
);
1799 return mem_overlaps_already_clobbered_arg_p (XEXP (x
, 0),
1800 GET_MODE_SIZE (GET_MODE (x
)));
1802 /* Scan all subexpressions. */
1803 fmt
= GET_RTX_FORMAT (code
);
1804 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
1808 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
1811 else if (*fmt
== 'E')
1813 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
1814 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
1821 /* Scan sequence after INSN if it does not dereference any argument slots
1822 we already clobbered by tail call arguments (as noted in stored_args_map
1823 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1824 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1825 should be 0). Return nonzero if sequence after INSN dereferences such argument
1826 slots, zero otherwise. */
1829 check_sibcall_argument_overlap (rtx insn
, struct arg_data
*arg
, int mark_stored_args_map
)
1833 if (insn
== NULL_RTX
)
1834 insn
= get_insns ();
1836 insn
= NEXT_INSN (insn
);
1838 for (; insn
; insn
= NEXT_INSN (insn
))
1840 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
1843 if (mark_stored_args_map
)
1845 #ifdef ARGS_GROW_DOWNWARD
1846 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
1848 low
= arg
->locate
.slot_offset
.constant
;
1851 for (high
= low
+ arg
->locate
.size
.constant
; low
< high
; low
++)
1852 SET_BIT (stored_args_map
, low
);
1854 return insn
!= NULL_RTX
;
1857 /* Given that a function returns a value of mode MODE at the most
1858 significant end of hard register VALUE, shift VALUE left or right
1859 as specified by LEFT_P. Return true if some action was needed. */
1862 shift_return_value (enum machine_mode mode
, bool left_p
, rtx value
)
1864 HOST_WIDE_INT shift
;
1866 gcc_assert (REG_P (value
) && HARD_REGISTER_P (value
));
1867 shift
= GET_MODE_BITSIZE (GET_MODE (value
)) - GET_MODE_BITSIZE (mode
);
1871 /* Use ashr rather than lshr for right shifts. This is for the benefit
1872 of the MIPS port, which requires SImode values to be sign-extended
1873 when stored in 64-bit registers. */
1874 if (!force_expand_binop (GET_MODE (value
), left_p
? ashl_optab
: ashr_optab
,
1875 value
, GEN_INT (shift
), value
, 1, OPTAB_WIDEN
))
1880 /* If X is a likely-spilled register value, copy it to a pseudo
1881 register and return that register. Return X otherwise. */
1884 avoid_likely_spilled_reg (rtx x
)
1889 && HARD_REGISTER_P (x
)
1890 && CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (REGNO (x
))))
1892 /* Make sure that we generate a REG rather than a CONCAT.
1893 Moves into CONCATs can need nontrivial instructions,
1894 and the whole point of this function is to avoid
1895 using the hard register directly in such a situation. */
1896 generating_concat_p
= 0;
1897 new_rtx
= gen_reg_rtx (GET_MODE (x
));
1898 generating_concat_p
= 1;
1899 emit_move_insn (new_rtx
, x
);
1905 /* Generate all the code for a CALL_EXPR exp
1906 and return an rtx for its value.
1907 Store the value in TARGET (specified as an rtx) if convenient.
1908 If the value is stored in TARGET then TARGET is returned.
1909 If IGNORE is nonzero, then we ignore the value of the function call. */
1912 expand_call (tree exp
, rtx target
, int ignore
)
1914 /* Nonzero if we are currently expanding a call. */
1915 static int currently_expanding_call
= 0;
1917 /* RTX for the function to be called. */
1919 /* Sequence of insns to perform a normal "call". */
1920 rtx normal_call_insns
= NULL_RTX
;
1921 /* Sequence of insns to perform a tail "call". */
1922 rtx tail_call_insns
= NULL_RTX
;
1923 /* Data type of the function. */
1925 tree type_arg_types
;
1927 /* Declaration of the function being called,
1928 or 0 if the function is computed (not known by name). */
1930 /* The type of the function being called. */
1932 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
1935 /* Register in which non-BLKmode value will be returned,
1936 or 0 if no value or if value is BLKmode. */
1938 /* Address where we should return a BLKmode value;
1939 0 if value not BLKmode. */
1940 rtx structure_value_addr
= 0;
1941 /* Nonzero if that address is being passed by treating it as
1942 an extra, implicit first parameter. Otherwise,
1943 it is passed by being copied directly into struct_value_rtx. */
1944 int structure_value_addr_parm
= 0;
1945 /* Holds the value of implicit argument for the struct value. */
1946 tree structure_value_addr_value
= NULL_TREE
;
1947 /* Size of aggregate value wanted, or zero if none wanted
1948 or if we are using the non-reentrant PCC calling convention
1949 or expecting the value in registers. */
1950 HOST_WIDE_INT struct_value_size
= 0;
1951 /* Nonzero if called function returns an aggregate in memory PCC style,
1952 by returning the address of where to find it. */
1953 int pcc_struct_value
= 0;
1954 rtx struct_value
= 0;
1956 /* Number of actual parameters in this call, including struct value addr. */
1958 /* Number of named args. Args after this are anonymous ones
1959 and they must all go on the stack. */
1961 /* Number of complex actual arguments that need to be split. */
1962 int num_complex_actuals
= 0;
1964 /* Vector of information about each argument.
1965 Arguments are numbered in the order they will be pushed,
1966 not the order they are written. */
1967 struct arg_data
*args
;
1969 /* Total size in bytes of all the stack-parms scanned so far. */
1970 struct args_size args_size
;
1971 struct args_size adjusted_args_size
;
1972 /* Size of arguments before any adjustments (such as rounding). */
1973 int unadjusted_args_size
;
1974 /* Data on reg parms scanned so far. */
1975 CUMULATIVE_ARGS args_so_far
;
1976 /* Nonzero if a reg parm has been scanned. */
1978 /* Nonzero if this is an indirect function call. */
1980 /* Nonzero if we must avoid push-insns in the args for this call.
1981 If stack space is allocated for register parameters, but not by the
1982 caller, then it is preallocated in the fixed part of the stack frame.
1983 So the entire argument block must then be preallocated (i.e., we
1984 ignore PUSH_ROUNDING in that case). */
1986 int must_preallocate
= !PUSH_ARGS
;
1988 /* Size of the stack reserved for parameter registers. */
1989 int reg_parm_stack_space
= 0;
1991 /* Address of space preallocated for stack parms
1992 (on machines that lack push insns), or 0 if space not preallocated. */
1995 /* Mask of ECF_ flags. */
1997 #ifdef REG_PARM_STACK_SPACE
1998 /* Define the boundary of the register parm stack space that needs to be
2000 int low_to_save
, high_to_save
;
2001 rtx save_area
= 0; /* Place that it is saved */
2004 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
2005 char *initial_stack_usage_map
= stack_usage_map
;
2006 char *stack_usage_map_buf
= NULL
;
2008 int old_stack_allocated
;
2010 /* State variables to track stack modifications. */
2011 rtx old_stack_level
= 0;
2012 int old_stack_arg_under_construction
= 0;
2013 int old_pending_adj
= 0;
2014 int old_inhibit_defer_pop
= inhibit_defer_pop
;
2016 /* Some stack pointer alterations we make are performed via
2017 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2018 which we then also need to save/restore along the way. */
2019 int old_stack_pointer_delta
= 0;
2022 tree addr
= CALL_EXPR_FN (exp
);
2024 /* The alignment of the stack, in bits. */
2025 unsigned HOST_WIDE_INT preferred_stack_boundary
;
2026 /* The alignment of the stack, in bytes. */
2027 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
2028 /* The static chain value to use for this call. */
2029 rtx static_chain_value
;
2030 /* See if this is "nothrow" function call. */
2031 if (TREE_NOTHROW (exp
))
2032 flags
|= ECF_NOTHROW
;
2034 /* See if we can find a DECL-node for the actual function, and get the
2035 function attributes (flags) from the function decl or type node. */
2036 fndecl
= get_callee_fndecl (exp
);
2039 fntype
= TREE_TYPE (fndecl
);
2040 flags
|= flags_from_decl_or_type (fndecl
);
2044 fntype
= TREE_TYPE (TREE_TYPE (addr
));
2045 flags
|= flags_from_decl_or_type (fntype
);
2047 rettype
= TREE_TYPE (exp
);
2049 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
2051 /* Warn if this value is an aggregate type,
2052 regardless of which calling convention we are using for it. */
2053 if (AGGREGATE_TYPE_P (rettype
))
2054 warning (OPT_Waggregate_return
, "function call has aggregate value");
2056 /* If the result of a non looping pure or const function call is
2057 ignored (or void), and none of its arguments are volatile, we can
2058 avoid expanding the call and just evaluate the arguments for
2060 if ((flags
& (ECF_CONST
| ECF_PURE
))
2061 && (!(flags
& ECF_LOOPING_CONST_OR_PURE
))
2062 && (ignore
|| target
== const0_rtx
2063 || TYPE_MODE (rettype
) == VOIDmode
))
2065 bool volatilep
= false;
2067 call_expr_arg_iterator iter
;
2069 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2070 if (TREE_THIS_VOLATILE (arg
))
2078 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2079 expand_expr (arg
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
2084 #ifdef REG_PARM_STACK_SPACE
2085 reg_parm_stack_space
= REG_PARM_STACK_SPACE (!fndecl
? fntype
: fndecl
);
2088 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
2089 && reg_parm_stack_space
> 0 && PUSH_ARGS
)
2090 must_preallocate
= 1;
2092 /* Set up a place to return a structure. */
2094 /* Cater to broken compilers. */
2095 if (aggregate_value_p (exp
, (!fndecl
? fntype
: fndecl
)))
2097 /* This call returns a big structure. */
2098 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
2100 #ifdef PCC_STATIC_STRUCT_RETURN
2102 pcc_struct_value
= 1;
2104 #else /* not PCC_STATIC_STRUCT_RETURN */
2106 struct_value_size
= int_size_in_bytes (rettype
);
2108 if (target
&& MEM_P (target
) && CALL_EXPR_RETURN_SLOT_OPT (exp
))
2109 structure_value_addr
= XEXP (target
, 0);
2112 /* For variable-sized objects, we must be called with a target
2113 specified. If we were to allocate space on the stack here,
2114 we would have no way of knowing when to free it. */
2115 rtx d
= assign_temp (rettype
, 0, 1, 1);
2117 mark_temp_addr_taken (d
);
2118 structure_value_addr
= XEXP (d
, 0);
2122 #endif /* not PCC_STATIC_STRUCT_RETURN */
2125 /* Figure out the amount to which the stack should be aligned. */
2126 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2129 struct cgraph_rtl_info
*i
= cgraph_rtl_info (fndecl
);
2130 /* Without automatic stack alignment, we can't increase preferred
2131 stack boundary. With automatic stack alignment, it is
2132 unnecessary since unless we can guarantee that all callers will
2133 align the outgoing stack properly, callee has to align its
2136 && i
->preferred_incoming_stack_boundary
2137 && i
->preferred_incoming_stack_boundary
< preferred_stack_boundary
)
2138 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
2141 /* Operand 0 is a pointer-to-function; get the type of the function. */
2142 funtype
= TREE_TYPE (addr
);
2143 gcc_assert (POINTER_TYPE_P (funtype
));
2144 funtype
= TREE_TYPE (funtype
);
2146 /* Count whether there are actual complex arguments that need to be split
2147 into their real and imaginary parts. Munge the type_arg_types
2148 appropriately here as well. */
2149 if (targetm
.calls
.split_complex_arg
)
2151 call_expr_arg_iterator iter
;
2153 FOR_EACH_CALL_EXPR_ARG (arg
, iter
, exp
)
2155 tree type
= TREE_TYPE (arg
);
2156 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
2157 && targetm
.calls
.split_complex_arg (type
))
2158 num_complex_actuals
++;
2160 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
2163 type_arg_types
= TYPE_ARG_TYPES (funtype
);
2165 if (flags
& ECF_MAY_BE_ALLOCA
)
2166 cfun
->calls_alloca
= 1;
2168 /* If struct_value_rtx is 0, it means pass the address
2169 as if it were an extra parameter. Put the argument expression
2170 in structure_value_addr_value. */
2171 if (structure_value_addr
&& struct_value
== 0)
2173 /* If structure_value_addr is a REG other than
2174 virtual_outgoing_args_rtx, we can use always use it. If it
2175 is not a REG, we must always copy it into a register.
2176 If it is virtual_outgoing_args_rtx, we must copy it to another
2177 register in some cases. */
2178 rtx temp
= (!REG_P (structure_value_addr
)
2179 || (ACCUMULATE_OUTGOING_ARGS
2180 && stack_arg_under_construction
2181 && structure_value_addr
== virtual_outgoing_args_rtx
)
2182 ? copy_addr_to_reg (convert_memory_address
2183 (Pmode
, structure_value_addr
))
2184 : structure_value_addr
);
2186 structure_value_addr_value
=
2187 make_tree (build_pointer_type (TREE_TYPE (funtype
)), temp
);
2188 structure_value_addr_parm
= 1;
2191 /* Count the arguments and set NUM_ACTUALS. */
2193 call_expr_nargs (exp
) + num_complex_actuals
+ structure_value_addr_parm
;
2195 /* Compute number of named args.
2196 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2198 if (type_arg_types
!= 0)
2200 = (list_length (type_arg_types
)
2201 /* Count the struct value address, if it is passed as a parm. */
2202 + structure_value_addr_parm
);
2204 /* If we know nothing, treat all args as named. */
2205 n_named_args
= num_actuals
;
2207 /* Start updating where the next arg would go.
2209 On some machines (such as the PA) indirect calls have a different
2210 calling convention than normal calls. The fourth argument in
2211 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2213 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
2215 /* Now possibly adjust the number of named args.
2216 Normally, don't include the last named arg if anonymous args follow.
2217 We do include the last named arg if
2218 targetm.calls.strict_argument_naming() returns nonzero.
2219 (If no anonymous args follow, the result of list_length is actually
2220 one too large. This is harmless.)
2222 If targetm.calls.pretend_outgoing_varargs_named() returns
2223 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2224 this machine will be able to place unnamed args that were passed
2225 in registers into the stack. So treat all args as named. This
2226 allows the insns emitting for a specific argument list to be
2227 independent of the function declaration.
2229 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2230 we do not have any reliable way to pass unnamed args in
2231 registers, so we must force them into memory. */
2233 if (type_arg_types
!= 0
2234 && targetm
.calls
.strict_argument_naming (&args_so_far
))
2236 else if (type_arg_types
!= 0
2237 && ! targetm
.calls
.pretend_outgoing_varargs_named (&args_so_far
))
2238 /* Don't include the last named arg. */
2241 /* Treat all args as named. */
2242 n_named_args
= num_actuals
;
2244 /* Make a vector to hold all the information about each arg. */
2245 args
= XALLOCAVEC (struct arg_data
, num_actuals
);
2246 memset (args
, 0, num_actuals
* sizeof (struct arg_data
));
2248 /* Build up entries in the ARGS array, compute the size of the
2249 arguments into ARGS_SIZE, etc. */
2250 initialize_argument_information (num_actuals
, args
, &args_size
,
2252 structure_value_addr_value
, fndecl
, fntype
,
2253 &args_so_far
, reg_parm_stack_space
,
2254 &old_stack_level
, &old_pending_adj
,
2255 &must_preallocate
, &flags
,
2256 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
2259 must_preallocate
= 1;
2261 /* Now make final decision about preallocating stack space. */
2262 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2266 /* If the structure value address will reference the stack pointer, we
2267 must stabilize it. We don't need to do this if we know that we are
2268 not going to adjust the stack pointer in processing this call. */
2270 if (structure_value_addr
2271 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2272 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2273 structure_value_addr
))
2275 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2276 structure_value_addr
= copy_to_reg (structure_value_addr
);
2278 /* Tail calls can make things harder to debug, and we've traditionally
2279 pushed these optimizations into -O2. Don't try if we're already
2280 expanding a call, as that means we're an argument. Don't try if
2281 there's cleanups, as we know there's code to follow the call. */
2283 if (currently_expanding_call
++ != 0
2284 || !flag_optimize_sibling_calls
2286 || dbg_cnt (tail_call
) == false)
2289 /* Rest of purposes for tail call optimizations to fail. */
2291 #ifdef HAVE_sibcall_epilogue
2292 !HAVE_sibcall_epilogue
2297 /* Doing sibling call optimization needs some work, since
2298 structure_value_addr can be allocated on the stack.
2299 It does not seem worth the effort since few optimizable
2300 sibling calls will return a structure. */
2301 || structure_value_addr
!= NULL_RTX
2302 #ifdef REG_PARM_STACK_SPACE
2303 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2304 || (OUTGOING_REG_PARM_STACK_SPACE (funtype
)
2305 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl
)))
2306 || (reg_parm_stack_space
!= REG_PARM_STACK_SPACE (fndecl
))
2308 /* Check whether the target is able to optimize the call
2310 || !targetm
.function_ok_for_sibcall (fndecl
, exp
)
2311 /* Functions that do not return exactly once may not be sibcall
2313 || (flags
& (ECF_RETURNS_TWICE
| ECF_NORETURN
))
2314 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
)))
2315 /* If the called function is nested in the current one, it might access
2316 some of the caller's arguments, but could clobber them beforehand if
2317 the argument areas are shared. */
2318 || (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
2319 /* If this function requires more stack slots than the current
2320 function, we cannot change it into a sibling call.
2321 crtl->args.pretend_args_size is not part of the
2322 stack allocated by our caller. */
2323 || args_size
.constant
> (crtl
->args
.size
2324 - crtl
->args
.pretend_args_size
)
2325 /* If the callee pops its own arguments, then it must pop exactly
2326 the same number of arguments as the current function. */
2327 || (RETURN_POPS_ARGS (fndecl
, funtype
, args_size
.constant
)
2328 != RETURN_POPS_ARGS (current_function_decl
,
2329 TREE_TYPE (current_function_decl
),
2331 || !lang_hooks
.decls
.ok_for_sibcall (fndecl
))
2334 /* Check if caller and callee disagree in promotion of function
2338 enum machine_mode caller_mode
, caller_promoted_mode
;
2339 enum machine_mode callee_mode
, callee_promoted_mode
;
2340 int caller_unsignedp
, callee_unsignedp
;
2341 tree caller_res
= DECL_RESULT (current_function_decl
);
2343 caller_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (caller_res
));
2344 caller_mode
= DECL_MODE (caller_res
);
2345 callee_unsignedp
= TYPE_UNSIGNED (TREE_TYPE (funtype
));
2346 callee_mode
= TYPE_MODE (TREE_TYPE (funtype
));
2347 caller_promoted_mode
2348 = promote_function_mode (TREE_TYPE (caller_res
), caller_mode
,
2350 TREE_TYPE (current_function_decl
), 1);
2351 callee_promoted_mode
2352 = promote_function_mode (TREE_TYPE (funtype
), callee_mode
,
2355 if (caller_mode
!= VOIDmode
2356 && (caller_promoted_mode
!= callee_promoted_mode
2357 || ((caller_mode
!= caller_promoted_mode
2358 || callee_mode
!= callee_promoted_mode
)
2359 && (caller_unsignedp
!= callee_unsignedp
2360 || GET_MODE_BITSIZE (caller_mode
)
2361 < GET_MODE_BITSIZE (callee_mode
)))))
2365 /* Ensure current function's preferred stack boundary is at least
2366 what we need. Stack alignment may also increase preferred stack
2368 if (crtl
->preferred_stack_boundary
< preferred_stack_boundary
)
2369 crtl
->preferred_stack_boundary
= preferred_stack_boundary
;
2371 preferred_stack_boundary
= crtl
->preferred_stack_boundary
;
2373 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2375 /* We want to make two insn chains; one for a sibling call, the other
2376 for a normal call. We will select one of the two chains after
2377 initial RTL generation is complete. */
2378 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
2380 int sibcall_failure
= 0;
2381 /* We want to emit any pending stack adjustments before the tail
2382 recursion "call". That way we know any adjustment after the tail
2383 recursion call can be ignored if we indeed use the tail
2385 int save_pending_stack_adjust
= 0;
2386 int save_stack_pointer_delta
= 0;
2388 rtx before_call
, next_arg_reg
, after_args
;
2392 /* State variables we need to save and restore between
2394 save_pending_stack_adjust
= pending_stack_adjust
;
2395 save_stack_pointer_delta
= stack_pointer_delta
;
2398 flags
&= ~ECF_SIBCALL
;
2400 flags
|= ECF_SIBCALL
;
2402 /* Other state variables that we must reinitialize each time
2403 through the loop (that are not initialized by the loop itself). */
2407 /* Start a new sequence for the normal call case.
2409 From this point on, if the sibling call fails, we want to set
2410 sibcall_failure instead of continuing the loop. */
2413 /* Don't let pending stack adjusts add up to too much.
2414 Also, do all pending adjustments now if there is any chance
2415 this might be a call to alloca or if we are expanding a sibling
2417 Also do the adjustments before a throwing call, otherwise
2418 exception handling can fail; PR 19225. */
2419 if (pending_stack_adjust
>= 32
2420 || (pending_stack_adjust
> 0
2421 && (flags
& ECF_MAY_BE_ALLOCA
))
2422 || (pending_stack_adjust
> 0
2423 && flag_exceptions
&& !(flags
& ECF_NOTHROW
))
2425 do_pending_stack_adjust ();
2427 /* Precompute any arguments as needed. */
2429 precompute_arguments (num_actuals
, args
);
2431 /* Now we are about to start emitting insns that can be deleted
2432 if a libcall is deleted. */
2433 if (pass
&& (flags
& ECF_MALLOC
))
2436 if (pass
== 0 && crtl
->stack_protect_guard
)
2437 stack_protect_epilogue ();
2439 adjusted_args_size
= args_size
;
2440 /* Compute the actual size of the argument block required. The variable
2441 and constant sizes must be combined, the size may have to be rounded,
2442 and there may be a minimum required size. When generating a sibcall
2443 pattern, do not round up, since we'll be re-using whatever space our
2445 unadjusted_args_size
2446 = compute_argument_block_size (reg_parm_stack_space
,
2447 &adjusted_args_size
,
2450 : preferred_stack_boundary
));
2452 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2454 /* The argument block when performing a sibling call is the
2455 incoming argument block. */
2458 argblock
= crtl
->args
.internal_arg_pointer
;
2460 #ifdef STACK_GROWS_DOWNWARD
2461 = plus_constant (argblock
, crtl
->args
.pretend_args_size
);
2463 = plus_constant (argblock
, -crtl
->args
.pretend_args_size
);
2465 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2466 sbitmap_zero (stored_args_map
);
2469 /* If we have no actual push instructions, or shouldn't use them,
2470 make space for all args right now. */
2471 else if (adjusted_args_size
.var
!= 0)
2473 if (old_stack_level
== 0)
2475 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
2476 old_stack_pointer_delta
= stack_pointer_delta
;
2477 old_pending_adj
= pending_stack_adjust
;
2478 pending_stack_adjust
= 0;
2479 /* stack_arg_under_construction says whether a stack arg is
2480 being constructed at the old stack level. Pushing the stack
2481 gets a clean outgoing argument block. */
2482 old_stack_arg_under_construction
= stack_arg_under_construction
;
2483 stack_arg_under_construction
= 0;
2485 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2489 /* Note that we must go through the motions of allocating an argument
2490 block even if the size is zero because we may be storing args
2491 in the area reserved for register arguments, which may be part of
2494 int needed
= adjusted_args_size
.constant
;
2496 /* Store the maximum argument space used. It will be pushed by
2497 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2500 if (needed
> crtl
->outgoing_args_size
)
2501 crtl
->outgoing_args_size
= needed
;
2503 if (must_preallocate
)
2505 if (ACCUMULATE_OUTGOING_ARGS
)
2507 /* Since the stack pointer will never be pushed, it is
2508 possible for the evaluation of a parm to clobber
2509 something we have already written to the stack.
2510 Since most function calls on RISC machines do not use
2511 the stack, this is uncommon, but must work correctly.
2513 Therefore, we save any area of the stack that was already
2514 written and that we are using. Here we set up to do this
2515 by making a new stack usage map from the old one. The
2516 actual save will be done by store_one_arg.
2518 Another approach might be to try to reorder the argument
2519 evaluations to avoid this conflicting stack usage. */
2521 /* Since we will be writing into the entire argument area,
2522 the map must be allocated for its entire size, not just
2523 the part that is the responsibility of the caller. */
2524 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
2525 needed
+= reg_parm_stack_space
;
2527 #ifdef ARGS_GROW_DOWNWARD
2528 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2531 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2534 if (stack_usage_map_buf
)
2535 free (stack_usage_map_buf
);
2536 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
2537 stack_usage_map
= stack_usage_map_buf
;
2539 if (initial_highest_arg_in_use
)
2540 memcpy (stack_usage_map
, initial_stack_usage_map
,
2541 initial_highest_arg_in_use
);
2543 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2544 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2545 (highest_outgoing_arg_in_use
2546 - initial_highest_arg_in_use
));
2549 /* The address of the outgoing argument list must not be
2550 copied to a register here, because argblock would be left
2551 pointing to the wrong place after the call to
2552 allocate_dynamic_stack_space below. */
2554 argblock
= virtual_outgoing_args_rtx
;
2558 if (inhibit_defer_pop
== 0)
2560 /* Try to reuse some or all of the pending_stack_adjust
2561 to get this space. */
2563 = (combine_pending_stack_adjustment_and_call
2564 (unadjusted_args_size
,
2565 &adjusted_args_size
,
2566 preferred_unit_stack_boundary
));
2568 /* combine_pending_stack_adjustment_and_call computes
2569 an adjustment before the arguments are allocated.
2570 Account for them and see whether or not the stack
2571 needs to go up or down. */
2572 needed
= unadjusted_args_size
- needed
;
2576 /* We're releasing stack space. */
2577 /* ??? We can avoid any adjustment at all if we're
2578 already aligned. FIXME. */
2579 pending_stack_adjust
= -needed
;
2580 do_pending_stack_adjust ();
2584 /* We need to allocate space. We'll do that in
2585 push_block below. */
2586 pending_stack_adjust
= 0;
2589 /* Special case this because overhead of `push_block' in
2590 this case is non-trivial. */
2592 argblock
= virtual_outgoing_args_rtx
;
2595 argblock
= push_block (GEN_INT (needed
), 0, 0);
2596 #ifdef ARGS_GROW_DOWNWARD
2597 argblock
= plus_constant (argblock
, needed
);
2601 /* We only really need to call `copy_to_reg' in the case
2602 where push insns are going to be used to pass ARGBLOCK
2603 to a function call in ARGS. In that case, the stack
2604 pointer changes value from the allocation point to the
2605 call point, and hence the value of
2606 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2607 as well always do it. */
2608 argblock
= copy_to_reg (argblock
);
2613 if (ACCUMULATE_OUTGOING_ARGS
)
2615 /* The save/restore code in store_one_arg handles all
2616 cases except one: a constructor call (including a C
2617 function returning a BLKmode struct) to initialize
2619 if (stack_arg_under_construction
)
2622 = GEN_INT (adjusted_args_size
.constant
2623 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
2624 : TREE_TYPE (fndecl
))) ? 0
2625 : reg_parm_stack_space
));
2626 if (old_stack_level
== 0)
2628 emit_stack_save (SAVE_BLOCK
, &old_stack_level
,
2630 old_stack_pointer_delta
= stack_pointer_delta
;
2631 old_pending_adj
= pending_stack_adjust
;
2632 pending_stack_adjust
= 0;
2633 /* stack_arg_under_construction says whether a stack
2634 arg is being constructed at the old stack level.
2635 Pushing the stack gets a clean outgoing argument
2637 old_stack_arg_under_construction
2638 = stack_arg_under_construction
;
2639 stack_arg_under_construction
= 0;
2640 /* Make a new map for the new argument list. */
2641 if (stack_usage_map_buf
)
2642 free (stack_usage_map_buf
);
2643 stack_usage_map_buf
= XCNEWVEC (char, highest_outgoing_arg_in_use
);
2644 stack_usage_map
= stack_usage_map_buf
;
2645 highest_outgoing_arg_in_use
= 0;
2647 allocate_dynamic_stack_space (push_size
, NULL_RTX
,
2651 /* If argument evaluation might modify the stack pointer,
2652 copy the address of the argument list to a register. */
2653 for (i
= 0; i
< num_actuals
; i
++)
2654 if (args
[i
].pass_on_stack
)
2656 argblock
= copy_addr_to_reg (argblock
);
2661 compute_argument_addresses (args
, argblock
, num_actuals
);
2663 /* If we push args individually in reverse order, perform stack alignment
2664 before the first push (the last arg). */
2665 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2666 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2668 /* When the stack adjustment is pending, we get better code
2669 by combining the adjustments. */
2670 if (pending_stack_adjust
2671 && ! inhibit_defer_pop
)
2673 pending_stack_adjust
2674 = (combine_pending_stack_adjustment_and_call
2675 (unadjusted_args_size
,
2676 &adjusted_args_size
,
2677 preferred_unit_stack_boundary
));
2678 do_pending_stack_adjust ();
2680 else if (argblock
== 0)
2681 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2682 - unadjusted_args_size
));
2684 /* Now that the stack is properly aligned, pops can't safely
2685 be deferred during the evaluation of the arguments. */
2688 funexp
= rtx_for_function_call (fndecl
, addr
);
2690 /* Figure out the register where the value, if any, will come back. */
2692 if (TYPE_MODE (rettype
) != VOIDmode
2693 && ! structure_value_addr
)
2695 if (pcc_struct_value
)
2696 valreg
= hard_function_value (build_pointer_type (rettype
),
2697 fndecl
, NULL
, (pass
== 0));
2699 valreg
= hard_function_value (rettype
, fndecl
, fntype
,
2702 /* If VALREG is a PARALLEL whose first member has a zero
2703 offset, use that. This is for targets such as m68k that
2704 return the same value in multiple places. */
2705 if (GET_CODE (valreg
) == PARALLEL
)
2707 rtx elem
= XVECEXP (valreg
, 0, 0);
2708 rtx where
= XEXP (elem
, 0);
2709 rtx offset
= XEXP (elem
, 1);
2710 if (offset
== const0_rtx
2711 && GET_MODE (where
) == GET_MODE (valreg
))
2716 /* Precompute all register parameters. It isn't safe to compute anything
2717 once we have started filling any specific hard regs. */
2718 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2720 if (CALL_EXPR_STATIC_CHAIN (exp
))
2721 static_chain_value
= expand_normal (CALL_EXPR_STATIC_CHAIN (exp
));
2723 static_chain_value
= 0;
2725 #ifdef REG_PARM_STACK_SPACE
2726 /* Save the fixed argument area if it's part of the caller's frame and
2727 is clobbered by argument setup for this call. */
2728 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2729 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2730 &low_to_save
, &high_to_save
);
2733 /* Now store (and compute if necessary) all non-register parms.
2734 These come before register parms, since they can require block-moves,
2735 which could clobber the registers used for register parms.
2736 Parms which have partial registers are not stored here,
2737 but we do preallocate space here if they want that. */
2739 for (i
= 0; i
< num_actuals
; i
++)
2741 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2743 rtx before_arg
= get_last_insn ();
2745 if (store_one_arg (&args
[i
], argblock
, flags
,
2746 adjusted_args_size
.var
!= 0,
2747 reg_parm_stack_space
)
2749 && check_sibcall_argument_overlap (before_arg
,
2751 sibcall_failure
= 1;
2754 if (((flags
& ECF_CONST
)
2755 || ((flags
& ECF_PURE
) && ACCUMULATE_OUTGOING_ARGS
))
2757 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
2758 gen_rtx_USE (VOIDmode
,
2763 /* If we have a parm that is passed in registers but not in memory
2764 and whose alignment does not permit a direct copy into registers,
2765 make a group of pseudos that correspond to each register that we
2767 if (STRICT_ALIGNMENT
)
2768 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2770 /* Now store any partially-in-registers parm.
2771 This is the last place a block-move can happen. */
2773 for (i
= 0; i
< num_actuals
; i
++)
2774 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2776 rtx before_arg
= get_last_insn ();
2778 if (store_one_arg (&args
[i
], argblock
, flags
,
2779 adjusted_args_size
.var
!= 0,
2780 reg_parm_stack_space
)
2782 && check_sibcall_argument_overlap (before_arg
,
2784 sibcall_failure
= 1;
2787 /* If we pushed args in forward order, perform stack alignment
2788 after pushing the last arg. */
2789 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
2790 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2791 - unadjusted_args_size
));
2793 /* If register arguments require space on the stack and stack space
2794 was not preallocated, allocate stack space here for arguments
2795 passed in registers. */
2796 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
)))
2797 && !ACCUMULATE_OUTGOING_ARGS
2798 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
2799 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
2801 /* Pass the function the address in which to return a
2803 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
2805 structure_value_addr
2806 = convert_memory_address (Pmode
, structure_value_addr
);
2807 emit_move_insn (struct_value
,
2809 force_operand (structure_value_addr
,
2812 if (REG_P (struct_value
))
2813 use_reg (&call_fusage
, struct_value
);
2816 after_args
= get_last_insn ();
2817 funexp
= prepare_call_address (fndecl
, funexp
, static_chain_value
,
2818 &call_fusage
, reg_parm_seen
, pass
== 0);
2820 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
2821 pass
== 0, &sibcall_failure
);
2823 /* Save a pointer to the last insn before the call, so that we can
2824 later safely search backwards to find the CALL_INSN. */
2825 before_call
= get_last_insn ();
2827 /* Set up next argument register. For sibling calls on machines
2828 with register windows this should be the incoming register. */
2829 #ifdef FUNCTION_INCOMING_ARG
2831 next_arg_reg
= FUNCTION_INCOMING_ARG (args_so_far
, VOIDmode
,
2835 next_arg_reg
= FUNCTION_ARG (args_so_far
, VOIDmode
,
2838 /* All arguments and registers used for the call must be set up by
2841 /* Stack must be properly aligned now. */
2843 || !(stack_pointer_delta
% preferred_unit_stack_boundary
));
2845 /* Generate the actual call instruction. */
2846 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
2847 adjusted_args_size
.constant
, struct_value_size
,
2848 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
2849 flags
, & args_so_far
);
2851 /* If the call setup or the call itself overlaps with anything
2852 of the argument setup we probably clobbered our call address.
2853 In that case we can't do sibcalls. */
2855 && check_sibcall_argument_overlap (after_args
, 0, 0))
2856 sibcall_failure
= 1;
2858 /* If a non-BLKmode value is returned at the most significant end
2859 of a register, shift the register right by the appropriate amount
2860 and update VALREG accordingly. BLKmode values are handled by the
2861 group load/store machinery below. */
2862 if (!structure_value_addr
2863 && !pcc_struct_value
2864 && TYPE_MODE (rettype
) != BLKmode
2865 && targetm
.calls
.return_in_msb (rettype
))
2867 if (shift_return_value (TYPE_MODE (rettype
), false, valreg
))
2868 sibcall_failure
= 1;
2869 valreg
= gen_rtx_REG (TYPE_MODE (rettype
), REGNO (valreg
));
2872 if (pass
&& (flags
& ECF_MALLOC
))
2874 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2877 /* The return value from a malloc-like function is a pointer. */
2878 if (TREE_CODE (rettype
) == POINTER_TYPE
)
2879 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
2881 emit_move_insn (temp
, valreg
);
2883 /* The return value from a malloc-like function can not alias
2885 last
= get_last_insn ();
2886 add_reg_note (last
, REG_NOALIAS
, temp
);
2888 /* Write out the sequence. */
2889 insns
= get_insns ();
2895 /* For calls to `setjmp', etc., inform
2896 function.c:setjmp_warnings that it should complain if
2897 nonvolatile values are live. For functions that cannot
2898 return, inform flow that control does not fall through. */
2900 if ((flags
& ECF_NORETURN
) || pass
== 0)
2902 /* The barrier must be emitted
2903 immediately after the CALL_INSN. Some ports emit more
2904 than just a CALL_INSN above, so we must search for it here. */
2906 rtx last
= get_last_insn ();
2907 while (!CALL_P (last
))
2909 last
= PREV_INSN (last
);
2910 /* There was no CALL_INSN? */
2911 gcc_assert (last
!= before_call
);
2914 emit_barrier_after (last
);
2916 /* Stack adjustments after a noreturn call are dead code.
2917 However when NO_DEFER_POP is in effect, we must preserve
2918 stack_pointer_delta. */
2919 if (inhibit_defer_pop
== 0)
2921 stack_pointer_delta
= old_stack_allocated
;
2922 pending_stack_adjust
= 0;
2926 /* If value type not void, return an rtx for the value. */
2928 if (TYPE_MODE (rettype
) == VOIDmode
2930 target
= const0_rtx
;
2931 else if (structure_value_addr
)
2933 if (target
== 0 || !MEM_P (target
))
2936 = gen_rtx_MEM (TYPE_MODE (rettype
),
2937 memory_address (TYPE_MODE (rettype
),
2938 structure_value_addr
));
2939 set_mem_attributes (target
, rettype
, 1);
2942 else if (pcc_struct_value
)
2944 /* This is the special C++ case where we need to
2945 know what the true target was. We take care to
2946 never use this value more than once in one expression. */
2947 target
= gen_rtx_MEM (TYPE_MODE (rettype
),
2948 copy_to_reg (valreg
));
2949 set_mem_attributes (target
, rettype
, 1);
2951 /* Handle calls that return values in multiple non-contiguous locations.
2952 The Irix 6 ABI has examples of this. */
2953 else if (GET_CODE (valreg
) == PARALLEL
)
2957 /* This will only be assigned once, so it can be readonly. */
2958 tree nt
= build_qualified_type (rettype
,
2959 (TYPE_QUALS (rettype
)
2960 | TYPE_QUAL_CONST
));
2962 target
= assign_temp (nt
, 0, 1, 1);
2965 if (! rtx_equal_p (target
, valreg
))
2966 emit_group_store (target
, valreg
, rettype
,
2967 int_size_in_bytes (rettype
));
2969 /* We can not support sibling calls for this case. */
2970 sibcall_failure
= 1;
2973 && GET_MODE (target
) == TYPE_MODE (rettype
)
2974 && GET_MODE (target
) == GET_MODE (valreg
))
2976 bool may_overlap
= false;
2978 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
2979 reg to a plain register. */
2980 if (!REG_P (target
) || HARD_REGISTER_P (target
))
2981 valreg
= avoid_likely_spilled_reg (valreg
);
2983 /* If TARGET is a MEM in the argument area, and we have
2984 saved part of the argument area, then we can't store
2985 directly into TARGET as it may get overwritten when we
2986 restore the argument save area below. Don't work too
2987 hard though and simply force TARGET to a register if it
2988 is a MEM; the optimizer is quite likely to sort it out. */
2989 if (ACCUMULATE_OUTGOING_ARGS
&& pass
&& MEM_P (target
))
2990 for (i
= 0; i
< num_actuals
; i
++)
2991 if (args
[i
].save_area
)
2998 target
= copy_to_reg (valreg
);
3001 /* TARGET and VALREG cannot be equal at this point
3002 because the latter would not have
3003 REG_FUNCTION_VALUE_P true, while the former would if
3004 it were referring to the same register.
3006 If they refer to the same register, this move will be
3007 a no-op, except when function inlining is being
3009 emit_move_insn (target
, valreg
);
3011 /* If we are setting a MEM, this code must be executed.
3012 Since it is emitted after the call insn, sibcall
3013 optimization cannot be performed in that case. */
3015 sibcall_failure
= 1;
3018 else if (TYPE_MODE (rettype
) == BLKmode
)
3021 if (GET_MODE (val
) != BLKmode
)
3022 val
= avoid_likely_spilled_reg (val
);
3023 target
= copy_blkmode_from_reg (target
, val
, rettype
);
3025 /* We can not support sibling calls for this case. */
3026 sibcall_failure
= 1;
3029 target
= copy_to_reg (avoid_likely_spilled_reg (valreg
));
3031 /* If we promoted this return value, make the proper SUBREG.
3032 TARGET might be const0_rtx here, so be careful. */
3034 && TYPE_MODE (rettype
) != BLKmode
3035 && GET_MODE (target
) != TYPE_MODE (rettype
))
3037 tree type
= rettype
;
3038 int unsignedp
= TYPE_UNSIGNED (type
);
3040 enum machine_mode pmode
;
3042 /* Ensure we promote as expected, and get the new unsignedness. */
3043 pmode
= promote_function_mode (type
, TYPE_MODE (type
), &unsignedp
,
3045 gcc_assert (GET_MODE (target
) == pmode
);
3047 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
3048 && (GET_MODE_SIZE (GET_MODE (target
))
3049 > GET_MODE_SIZE (TYPE_MODE (type
))))
3051 offset
= GET_MODE_SIZE (GET_MODE (target
))
3052 - GET_MODE_SIZE (TYPE_MODE (type
));
3053 if (! BYTES_BIG_ENDIAN
)
3054 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
3055 else if (! WORDS_BIG_ENDIAN
)
3056 offset
%= UNITS_PER_WORD
;
3059 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
3060 SUBREG_PROMOTED_VAR_P (target
) = 1;
3061 SUBREG_PROMOTED_UNSIGNED_SET (target
, unsignedp
);
3064 /* If size of args is variable or this was a constructor call for a stack
3065 argument, restore saved stack-pointer value. */
3067 if (old_stack_level
)
3069 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
3070 stack_pointer_delta
= old_stack_pointer_delta
;
3071 pending_stack_adjust
= old_pending_adj
;
3072 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
3073 stack_arg_under_construction
= old_stack_arg_under_construction
;
3074 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3075 stack_usage_map
= initial_stack_usage_map
;
3076 sibcall_failure
= 1;
3078 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
3080 #ifdef REG_PARM_STACK_SPACE
3082 restore_fixed_argument_area (save_area
, argblock
,
3083 high_to_save
, low_to_save
);
3086 /* If we saved any argument areas, restore them. */
3087 for (i
= 0; i
< num_actuals
; i
++)
3088 if (args
[i
].save_area
)
3090 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
3092 = gen_rtx_MEM (save_mode
,
3093 memory_address (save_mode
,
3094 XEXP (args
[i
].stack_slot
, 0)));
3096 if (save_mode
!= BLKmode
)
3097 emit_move_insn (stack_area
, args
[i
].save_area
);
3099 emit_block_move (stack_area
, args
[i
].save_area
,
3100 GEN_INT (args
[i
].locate
.size
.constant
),
3101 BLOCK_OP_CALL_PARM
);
3104 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3105 stack_usage_map
= initial_stack_usage_map
;
3108 /* If this was alloca, record the new stack level for nonlocal gotos.
3109 Check for the handler slots since we might not have a save area
3110 for non-local gotos. */
3112 if ((flags
& ECF_MAY_BE_ALLOCA
) && cfun
->nonlocal_goto_save_area
!= 0)
3113 update_nonlocal_goto_save_area ();
3115 /* Free up storage we no longer need. */
3116 for (i
= 0; i
< num_actuals
; ++i
)
3117 if (args
[i
].aligned_regs
)
3118 free (args
[i
].aligned_regs
);
3120 insns
= get_insns ();
3125 tail_call_insns
= insns
;
3127 /* Restore the pending stack adjustment now that we have
3128 finished generating the sibling call sequence. */
3130 pending_stack_adjust
= save_pending_stack_adjust
;
3131 stack_pointer_delta
= save_stack_pointer_delta
;
3133 /* Prepare arg structure for next iteration. */
3134 for (i
= 0; i
< num_actuals
; i
++)
3137 args
[i
].aligned_regs
= 0;
3141 sbitmap_free (stored_args_map
);
3145 normal_call_insns
= insns
;
3147 /* Verify that we've deallocated all the stack we used. */
3148 gcc_assert ((flags
& ECF_NORETURN
)
3149 || (old_stack_allocated
3150 == stack_pointer_delta
- pending_stack_adjust
));
3153 /* If something prevents making this a sibling call,
3154 zero out the sequence. */
3155 if (sibcall_failure
)
3156 tail_call_insns
= NULL_RTX
;
3161 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3162 arguments too, as argument area is now clobbered by the call. */
3163 if (tail_call_insns
)
3165 emit_insn (tail_call_insns
);
3166 crtl
->tail_call_emit
= true;
3169 emit_insn (normal_call_insns
);
3171 currently_expanding_call
--;
3173 if (stack_usage_map_buf
)
3174 free (stack_usage_map_buf
);
3179 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3180 this function's incoming arguments.
3182 At the start of RTL generation we know the only REG_EQUIV notes
3183 in the rtl chain are those for incoming arguments, so we can look
3184 for REG_EQUIV notes between the start of the function and the
3185 NOTE_INSN_FUNCTION_BEG.
3187 This is (slight) overkill. We could keep track of the highest
3188 argument we clobber and be more selective in removing notes, but it
3189 does not seem to be worth the effort. */
3192 fixup_tail_calls (void)
3196 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
3200 /* There are never REG_EQUIV notes for the incoming arguments
3201 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3203 && NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
)
3206 note
= find_reg_note (insn
, REG_EQUIV
, 0);
3208 remove_note (insn
, note
);
3209 note
= find_reg_note (insn
, REG_EQUIV
, 0);
3214 /* Traverse a list of TYPES and expand all complex types into their
3217 split_complex_types (tree types
)
3221 /* Before allocating memory, check for the common case of no complex. */
3222 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3224 tree type
= TREE_VALUE (p
);
3225 if (TREE_CODE (type
) == COMPLEX_TYPE
3226 && targetm
.calls
.split_complex_arg (type
))
3232 types
= copy_list (types
);
3234 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3236 tree complex_type
= TREE_VALUE (p
);
3238 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
3239 && targetm
.calls
.split_complex_arg (complex_type
))
3243 /* Rewrite complex type with component type. */
3244 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
3245 next
= TREE_CHAIN (p
);
3247 /* Add another component type for the imaginary part. */
3248 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
3249 TREE_CHAIN (p
) = imag
;
3250 TREE_CHAIN (imag
) = next
;
3252 /* Skip the newly created node. */
3260 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3261 The RETVAL parameter specifies whether return value needs to be saved, other
3262 parameters are documented in the emit_library_call function below. */
3265 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
3266 enum libcall_type fn_type
,
3267 enum machine_mode outmode
, int nargs
, va_list p
)
3269 /* Total size in bytes of all the stack-parms scanned so far. */
3270 struct args_size args_size
;
3271 /* Size of arguments before any adjustments (such as rounding). */
3272 struct args_size original_args_size
;
3275 /* Todo, choose the correct decl type of orgfun. Sadly this information
3276 isn't present here, so we default to native calling abi here. */
3277 tree fndecl ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
3278 tree fntype ATTRIBUTE_UNUSED
= NULL_TREE
; /* library calls default to host calling abi ? */
3282 CUMULATIVE_ARGS args_so_far
;
3286 enum machine_mode mode
;
3289 struct locate_and_pad_arg_data locate
;
3293 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3294 rtx call_fusage
= 0;
3297 int pcc_struct_value
= 0;
3298 int struct_value_size
= 0;
3300 int reg_parm_stack_space
= 0;
3303 tree tfom
; /* type_for_mode (outmode, 0) */
3305 #ifdef REG_PARM_STACK_SPACE
3306 /* Define the boundary of the register parm stack space that needs to be
3308 int low_to_save
= 0, high_to_save
= 0;
3309 rtx save_area
= 0; /* Place that it is saved. */
3312 /* Size of the stack reserved for parameter registers. */
3313 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3314 char *initial_stack_usage_map
= stack_usage_map
;
3315 char *stack_usage_map_buf
= NULL
;
3317 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
3319 #ifdef REG_PARM_STACK_SPACE
3320 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3323 /* By default, library functions can not throw. */
3324 flags
= ECF_NOTHROW
;
3337 flags
|= ECF_NORETURN
;
3340 flags
= ECF_NORETURN
;
3342 case LCT_RETURNS_TWICE
:
3343 flags
= ECF_RETURNS_TWICE
;
3348 /* Ensure current function's preferred stack boundary is at least
3350 if (crtl
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3351 crtl
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3353 /* If this kind of value comes back in memory,
3354 decide where in memory it should come back. */
3355 if (outmode
!= VOIDmode
)
3357 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
3358 if (aggregate_value_p (tfom
, 0))
3360 #ifdef PCC_STATIC_STRUCT_RETURN
3362 = hard_function_value (build_pointer_type (tfom
), 0, 0, 0);
3363 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3364 pcc_struct_value
= 1;
3366 value
= gen_reg_rtx (outmode
);
3367 #else /* not PCC_STATIC_STRUCT_RETURN */
3368 struct_value_size
= GET_MODE_SIZE (outmode
);
3369 if (value
!= 0 && MEM_P (value
))
3372 mem_value
= assign_temp (tfom
, 0, 1, 1);
3374 /* This call returns a big structure. */
3375 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LOOPING_CONST_OR_PURE
);
3379 tfom
= void_type_node
;
3381 /* ??? Unfinished: must pass the memory address as an argument. */
3383 /* Copy all the libcall-arguments out of the varargs data
3384 and into a vector ARGVEC.
3386 Compute how to pass each argument. We only support a very small subset
3387 of the full argument passing conventions to limit complexity here since
3388 library functions shouldn't have many args. */
3390 argvec
= XALLOCAVEC (struct arg
, nargs
+ 1);
3391 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3393 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3394 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3396 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0, nargs
);
3399 args_size
.constant
= 0;
3406 /* If there's a structure value address to be passed,
3407 either pass it in the special place, or pass it as an extra argument. */
3408 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
3410 rtx addr
= XEXP (mem_value
, 0);
3414 /* Make sure it is a reasonable operand for a move or push insn. */
3415 if (!REG_P (addr
) && !MEM_P (addr
)
3416 && ! (CONSTANT_P (addr
) && LEGITIMATE_CONSTANT_P (addr
)))
3417 addr
= force_operand (addr
, NULL_RTX
);
3419 argvec
[count
].value
= addr
;
3420 argvec
[count
].mode
= Pmode
;
3421 argvec
[count
].partial
= 0;
3423 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, Pmode
, NULL_TREE
, 1);
3424 gcc_assert (targetm
.calls
.arg_partial_bytes (&args_so_far
, Pmode
,
3425 NULL_TREE
, 1) == 0);
3427 locate_and_pad_parm (Pmode
, NULL_TREE
,
3428 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3431 argvec
[count
].reg
!= 0,
3433 0, NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3435 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3436 || reg_parm_stack_space
> 0)
3437 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3439 FUNCTION_ARG_ADVANCE (args_so_far
, Pmode
, (tree
) 0, 1);
3444 for (; count
< nargs
; count
++)
3446 rtx val
= va_arg (p
, rtx
);
3447 enum machine_mode mode
= (enum machine_mode
) va_arg (p
, int);
3449 /* We cannot convert the arg value to the mode the library wants here;
3450 must do it earlier where we know the signedness of the arg. */
3451 gcc_assert (mode
!= BLKmode
3452 && (GET_MODE (val
) == mode
|| GET_MODE (val
) == VOIDmode
));
3454 /* Make sure it is a reasonable operand for a move or push insn. */
3455 if (!REG_P (val
) && !MEM_P (val
)
3456 && ! (CONSTANT_P (val
) && LEGITIMATE_CONSTANT_P (val
)))
3457 val
= force_operand (val
, NULL_RTX
);
3459 if (pass_by_reference (&args_so_far
, mode
, NULL_TREE
, 1))
3463 = !reference_callee_copied (&args_so_far
, mode
, NULL_TREE
, 1);
3465 /* If this was a CONST function, it is now PURE since it now
3467 if (flags
& ECF_CONST
)
3469 flags
&= ~ECF_CONST
;
3473 if (MEM_P (val
) && !must_copy
)
3477 slot
= assign_temp (lang_hooks
.types
.type_for_mode (mode
, 0),
3479 emit_move_insn (slot
, val
);
3482 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3483 gen_rtx_USE (VOIDmode
, slot
),
3486 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3487 gen_rtx_CLOBBER (VOIDmode
,
3492 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3495 argvec
[count
].value
= val
;
3496 argvec
[count
].mode
= mode
;
3498 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, mode
, NULL_TREE
, 1);
3500 argvec
[count
].partial
3501 = targetm
.calls
.arg_partial_bytes (&args_so_far
, mode
, NULL_TREE
, 1);
3503 locate_and_pad_parm (mode
, NULL_TREE
,
3504 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3507 argvec
[count
].reg
!= 0,
3509 argvec
[count
].partial
,
3510 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3512 gcc_assert (!argvec
[count
].locate
.size
.var
);
3514 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3515 || reg_parm_stack_space
> 0)
3516 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3518 FUNCTION_ARG_ADVANCE (args_so_far
, mode
, (tree
) 0, 1);
3521 /* If this machine requires an external definition for library
3522 functions, write one out. */
3523 assemble_external_libcall (fun
);
3525 original_args_size
= args_size
;
3526 args_size
.constant
= (((args_size
.constant
3527 + stack_pointer_delta
3531 - stack_pointer_delta
);
3533 args_size
.constant
= MAX (args_size
.constant
,
3534 reg_parm_stack_space
);
3536 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3537 args_size
.constant
-= reg_parm_stack_space
;
3539 if (args_size
.constant
> crtl
->outgoing_args_size
)
3540 crtl
->outgoing_args_size
= args_size
.constant
;
3542 if (ACCUMULATE_OUTGOING_ARGS
)
3544 /* Since the stack pointer will never be pushed, it is possible for
3545 the evaluation of a parm to clobber something we have already
3546 written to the stack. Since most function calls on RISC machines
3547 do not use the stack, this is uncommon, but must work correctly.
3549 Therefore, we save any area of the stack that was already written
3550 and that we are using. Here we set up to do this by making a new
3551 stack usage map from the old one.
3553 Another approach might be to try to reorder the argument
3554 evaluations to avoid this conflicting stack usage. */
3556 needed
= args_size
.constant
;
3558 /* Since we will be writing into the entire argument area, the
3559 map must be allocated for its entire size, not just the part that
3560 is the responsibility of the caller. */
3561 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl
? fntype
: TREE_TYPE (fndecl
))))
3562 needed
+= reg_parm_stack_space
;
3564 #ifdef ARGS_GROW_DOWNWARD
3565 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3568 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3571 stack_usage_map_buf
= XNEWVEC (char, highest_outgoing_arg_in_use
);
3572 stack_usage_map
= stack_usage_map_buf
;
3574 if (initial_highest_arg_in_use
)
3575 memcpy (stack_usage_map
, initial_stack_usage_map
,
3576 initial_highest_arg_in_use
);
3578 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3579 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3580 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3583 /* We must be careful to use virtual regs before they're instantiated,
3584 and real regs afterwards. Loop optimization, for example, can create
3585 new libcalls after we've instantiated the virtual regs, and if we
3586 use virtuals anyway, they won't match the rtl patterns. */
3588 if (virtuals_instantiated
)
3589 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3591 argblock
= virtual_outgoing_args_rtx
;
3596 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3599 /* If we push args individually in reverse order, perform stack alignment
3600 before the first push (the last arg). */
3601 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3602 anti_adjust_stack (GEN_INT (args_size
.constant
3603 - original_args_size
.constant
));
3605 if (PUSH_ARGS_REVERSED
)
3616 #ifdef REG_PARM_STACK_SPACE
3617 if (ACCUMULATE_OUTGOING_ARGS
)
3619 /* The argument list is the property of the called routine and it
3620 may clobber it. If the fixed area has been used for previous
3621 parameters, we must save and restore it. */
3622 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
3623 &low_to_save
, &high_to_save
);
3627 /* Push the args that need to be pushed. */
3629 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3630 are to be pushed. */
3631 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3633 enum machine_mode mode
= argvec
[argnum
].mode
;
3634 rtx val
= argvec
[argnum
].value
;
3635 rtx reg
= argvec
[argnum
].reg
;
3636 int partial
= argvec
[argnum
].partial
;
3637 unsigned int parm_align
= argvec
[argnum
].locate
.boundary
;
3638 int lower_bound
= 0, upper_bound
= 0, i
;
3640 if (! (reg
!= 0 && partial
== 0))
3642 if (ACCUMULATE_OUTGOING_ARGS
)
3644 /* If this is being stored into a pre-allocated, fixed-size,
3645 stack area, save any previous data at that location. */
3647 #ifdef ARGS_GROW_DOWNWARD
3648 /* stack_slot is negative, but we want to index stack_usage_map
3649 with positive values. */
3650 upper_bound
= -argvec
[argnum
].locate
.slot_offset
.constant
+ 1;
3651 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
3653 lower_bound
= argvec
[argnum
].locate
.slot_offset
.constant
;
3654 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
3658 /* Don't worry about things in the fixed argument area;
3659 it has already been saved. */
3660 if (i
< reg_parm_stack_space
)
3661 i
= reg_parm_stack_space
;
3662 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
3665 if (i
< upper_bound
)
3667 /* We need to make a save area. */
3669 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
3670 enum machine_mode save_mode
3671 = mode_for_size (size
, MODE_INT
, 1);
3673 = plus_constant (argblock
,
3674 argvec
[argnum
].locate
.offset
.constant
);
3676 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
3678 if (save_mode
== BLKmode
)
3680 argvec
[argnum
].save_area
3681 = assign_stack_temp (BLKmode
,
3682 argvec
[argnum
].locate
.size
.constant
,
3685 emit_block_move (validize_mem (argvec
[argnum
].save_area
),
3687 GEN_INT (argvec
[argnum
].locate
.size
.constant
),
3688 BLOCK_OP_CALL_PARM
);
3692 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3694 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3699 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, parm_align
,
3700 partial
, reg
, 0, argblock
,
3701 GEN_INT (argvec
[argnum
].locate
.offset
.constant
),
3702 reg_parm_stack_space
,
3703 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
));
3705 /* Now mark the segment we just used. */
3706 if (ACCUMULATE_OUTGOING_ARGS
)
3707 for (i
= lower_bound
; i
< upper_bound
; i
++)
3708 stack_usage_map
[i
] = 1;
3712 if ((flags
& ECF_CONST
)
3713 || ((flags
& ECF_PURE
) && ACCUMULATE_OUTGOING_ARGS
))
3717 /* Indicate argument access so that alias.c knows that these
3720 use
= plus_constant (argblock
,
3721 argvec
[argnum
].locate
.offset
.constant
);
3723 /* When arguments are pushed, trying to tell alias.c where
3724 exactly this argument is won't work, because the
3725 auto-increment causes confusion. So we merely indicate
3726 that we access something with a known mode somewhere on
3728 use
= gen_rtx_PLUS (Pmode
, virtual_outgoing_args_rtx
,
3729 gen_rtx_SCRATCH (Pmode
));
3730 use
= gen_rtx_MEM (argvec
[argnum
].mode
, use
);
3731 use
= gen_rtx_USE (VOIDmode
, use
);
3732 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
, use
, call_fusage
);
3737 /* If we pushed args in forward order, perform stack alignment
3738 after pushing the last arg. */
3739 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3740 anti_adjust_stack (GEN_INT (args_size
.constant
3741 - original_args_size
.constant
));
3743 if (PUSH_ARGS_REVERSED
)
3748 fun
= prepare_call_address (NULL
, fun
, NULL
, &call_fusage
, 0, 0);
3750 /* Now load any reg parms into their regs. */
3752 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3753 are to be pushed. */
3754 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3756 enum machine_mode mode
= argvec
[argnum
].mode
;
3757 rtx val
= argvec
[argnum
].value
;
3758 rtx reg
= argvec
[argnum
].reg
;
3759 int partial
= argvec
[argnum
].partial
;
3761 /* Handle calls that pass values in multiple non-contiguous
3762 locations. The PA64 has examples of this for library calls. */
3763 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3764 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
3765 else if (reg
!= 0 && partial
== 0)
3766 emit_move_insn (reg
, val
);
3771 /* Any regs containing parms remain in use through the call. */
3772 for (count
= 0; count
< nargs
; count
++)
3774 rtx reg
= argvec
[count
].reg
;
3775 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3776 use_group_regs (&call_fusage
, reg
);
3779 int partial
= argvec
[count
].partial
;
3783 gcc_assert (partial
% UNITS_PER_WORD
== 0);
3784 nregs
= partial
/ UNITS_PER_WORD
;
3785 use_regs (&call_fusage
, REGNO (reg
), nregs
);
3788 use_reg (&call_fusage
, reg
);
3792 /* Pass the function the address in which to return a structure value. */
3793 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
3795 emit_move_insn (struct_value
,
3797 force_operand (XEXP (mem_value
, 0),
3799 if (REG_P (struct_value
))
3800 use_reg (&call_fusage
, struct_value
);
3803 /* Don't allow popping to be deferred, since then
3804 cse'ing of library calls could delete a call and leave the pop. */
3806 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
3807 ? hard_libcall_value (outmode
, orgfun
) : NULL_RTX
);
3809 /* Stack must be properly aligned now. */
3810 gcc_assert (!(stack_pointer_delta
3811 & (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1)));
3813 before_call
= get_last_insn ();
3815 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3816 will set inhibit_defer_pop to that value. */
3817 /* The return type is needed to decide how many bytes the function pops.
3818 Signedness plays no role in that, so for simplicity, we pretend it's
3819 always signed. We also assume that the list of arguments passed has
3820 no impact, so we pretend it is unknown. */
3822 emit_call_1 (fun
, NULL
,
3823 get_identifier (XSTR (orgfun
, 0)),
3824 build_function_type (tfom
, NULL_TREE
),
3825 original_args_size
.constant
, args_size
.constant
,
3827 FUNCTION_ARG (args_so_far
, VOIDmode
, void_type_node
, 1),
3829 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, & args_so_far
);
3831 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
3832 that it should complain if nonvolatile values are live. For
3833 functions that cannot return, inform flow that control does not
3836 if (flags
& ECF_NORETURN
)
3838 /* The barrier note must be emitted
3839 immediately after the CALL_INSN. Some ports emit more than
3840 just a CALL_INSN above, so we must search for it here. */
3842 rtx last
= get_last_insn ();
3843 while (!CALL_P (last
))
3845 last
= PREV_INSN (last
);
3846 /* There was no CALL_INSN? */
3847 gcc_assert (last
!= before_call
);
3850 emit_barrier_after (last
);
3853 /* Now restore inhibit_defer_pop to its actual original value. */
3858 /* Copy the value to the right place. */
3859 if (outmode
!= VOIDmode
&& retval
)
3865 if (value
!= mem_value
)
3866 emit_move_insn (value
, mem_value
);
3868 else if (GET_CODE (valreg
) == PARALLEL
)
3871 value
= gen_reg_rtx (outmode
);
3872 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
3876 /* Convert to the proper mode if a promotion has been active. */
3877 if (GET_MODE (valreg
) != outmode
)
3879 int unsignedp
= TYPE_UNSIGNED (tfom
);
3881 gcc_assert (promote_function_mode (tfom
, outmode
, &unsignedp
,
3882 fndecl
? TREE_TYPE (fndecl
) : fntype
, 1)
3883 == GET_MODE (valreg
));
3884 valreg
= convert_modes (outmode
, GET_MODE (valreg
), valreg
, 0);
3888 emit_move_insn (value
, valreg
);
3894 if (ACCUMULATE_OUTGOING_ARGS
)
3896 #ifdef REG_PARM_STACK_SPACE
3898 restore_fixed_argument_area (save_area
, argblock
,
3899 high_to_save
, low_to_save
);
3902 /* If we saved any argument areas, restore them. */
3903 for (count
= 0; count
< nargs
; count
++)
3904 if (argvec
[count
].save_area
)
3906 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
3907 rtx adr
= plus_constant (argblock
,
3908 argvec
[count
].locate
.offset
.constant
);
3909 rtx stack_area
= gen_rtx_MEM (save_mode
,
3910 memory_address (save_mode
, adr
));
3912 if (save_mode
== BLKmode
)
3913 emit_block_move (stack_area
,
3914 validize_mem (argvec
[count
].save_area
),
3915 GEN_INT (argvec
[count
].locate
.size
.constant
),
3916 BLOCK_OP_CALL_PARM
);
3918 emit_move_insn (stack_area
, argvec
[count
].save_area
);
3921 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3922 stack_usage_map
= initial_stack_usage_map
;
3925 if (stack_usage_map_buf
)
3926 free (stack_usage_map_buf
);
3932 /* Output a library call to function FUN (a SYMBOL_REF rtx)
3933 (emitting the queue unless NO_QUEUE is nonzero),
3934 for a value of mode OUTMODE,
3935 with NARGS different arguments, passed as alternating rtx values
3936 and machine_modes to convert them to.
3938 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
3939 `const' calls, LCT_PURE for `pure' calls, or other LCT_ value for
3940 other types of library calls. */
3943 emit_library_call (rtx orgfun
, enum libcall_type fn_type
,
3944 enum machine_mode outmode
, int nargs
, ...)
3948 va_start (p
, nargs
);
3949 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
3953 /* Like emit_library_call except that an extra argument, VALUE,
3954 comes second and says where to store the result.
3955 (If VALUE is zero, this function chooses a convenient way
3956 to return the value.
3958 This function returns an rtx for where the value is to be found.
3959 If VALUE is nonzero, VALUE is returned. */
3962 emit_library_call_value (rtx orgfun
, rtx value
,
3963 enum libcall_type fn_type
,
3964 enum machine_mode outmode
, int nargs
, ...)
3969 va_start (p
, nargs
);
3970 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
3977 /* Store a single argument for a function call
3978 into the register or memory area where it must be passed.
3979 *ARG describes the argument value and where to pass it.
3981 ARGBLOCK is the address of the stack-block for all the arguments,
3982 or 0 on a machine where arguments are pushed individually.
3984 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
3985 so must be careful about how the stack is used.
3987 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
3988 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
3989 that we need not worry about saving and restoring the stack.
3991 FNDECL is the declaration of the function we are calling.
3993 Return nonzero if this arg should cause sibcall failure,
3997 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
3998 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
4000 tree pval
= arg
->tree_value
;
4004 int i
, lower_bound
= 0, upper_bound
= 0;
4005 int sibcall_failure
= 0;
4007 if (TREE_CODE (pval
) == ERROR_MARK
)
4010 /* Push a new temporary level for any temporaries we make for
4014 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4016 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4017 save any previous data at that location. */
4018 if (argblock
&& ! variable_size
&& arg
->stack
)
4020 #ifdef ARGS_GROW_DOWNWARD
4021 /* stack_slot is negative, but we want to index stack_usage_map
4022 with positive values. */
4023 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4024 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4028 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
4030 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4031 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4035 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
4039 /* Don't worry about things in the fixed argument area;
4040 it has already been saved. */
4041 if (i
< reg_parm_stack_space
)
4042 i
= reg_parm_stack_space
;
4043 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
4046 if (i
< upper_bound
)
4048 /* We need to make a save area. */
4049 unsigned int size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
4050 enum machine_mode save_mode
= mode_for_size (size
, MODE_INT
, 1);
4051 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
4052 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
4054 if (save_mode
== BLKmode
)
4056 tree ot
= TREE_TYPE (arg
->tree_value
);
4057 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4058 | TYPE_QUAL_CONST
));
4060 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4061 preserve_temp_slots (arg
->save_area
);
4062 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4063 GEN_INT (arg
->locate
.size
.constant
),
4064 BLOCK_OP_CALL_PARM
);
4068 arg
->save_area
= gen_reg_rtx (save_mode
);
4069 emit_move_insn (arg
->save_area
, stack_area
);
4075 /* If this isn't going to be placed on both the stack and in registers,
4076 set up the register and number of words. */
4077 if (! arg
->pass_on_stack
)
4079 if (flags
& ECF_SIBCALL
)
4080 reg
= arg
->tail_call_reg
;
4083 partial
= arg
->partial
;
4086 /* Being passed entirely in a register. We shouldn't be called in
4088 gcc_assert (reg
== 0 || partial
!= 0);
4090 /* If this arg needs special alignment, don't load the registers
4092 if (arg
->n_aligned_regs
!= 0)
4095 /* If this is being passed partially in a register, we can't evaluate
4096 it directly into its stack slot. Otherwise, we can. */
4097 if (arg
->value
== 0)
4099 /* stack_arg_under_construction is nonzero if a function argument is
4100 being evaluated directly into the outgoing argument list and
4101 expand_call must take special action to preserve the argument list
4102 if it is called recursively.
4104 For scalar function arguments stack_usage_map is sufficient to
4105 determine which stack slots must be saved and restored. Scalar
4106 arguments in general have pass_on_stack == 0.
4108 If this argument is initialized by a function which takes the
4109 address of the argument (a C++ constructor or a C function
4110 returning a BLKmode structure), then stack_usage_map is
4111 insufficient and expand_call must push the stack around the
4112 function call. Such arguments have pass_on_stack == 1.
4114 Note that it is always safe to set stack_arg_under_construction,
4115 but this generates suboptimal code if set when not needed. */
4117 if (arg
->pass_on_stack
)
4118 stack_arg_under_construction
++;
4120 arg
->value
= expand_expr (pval
,
4122 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4123 ? NULL_RTX
: arg
->stack
,
4124 VOIDmode
, EXPAND_STACK_PARM
);
4126 /* If we are promoting object (or for any other reason) the mode
4127 doesn't agree, convert the mode. */
4129 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4130 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4131 arg
->value
, arg
->unsignedp
);
4133 if (arg
->pass_on_stack
)
4134 stack_arg_under_construction
--;
4137 /* Check for overlap with already clobbered argument area. */
4138 if ((flags
& ECF_SIBCALL
)
4139 && MEM_P (arg
->value
)
4140 && mem_overlaps_already_clobbered_arg_p (XEXP (arg
->value
, 0),
4141 arg
->locate
.size
.constant
))
4142 sibcall_failure
= 1;
4144 /* Don't allow anything left on stack from computation
4145 of argument to alloca. */
4146 if (flags
& ECF_MAY_BE_ALLOCA
)
4147 do_pending_stack_adjust ();
4149 if (arg
->value
== arg
->stack
)
4150 /* If the value is already in the stack slot, we are done. */
4152 else if (arg
->mode
!= BLKmode
)
4155 unsigned int parm_align
;
4157 /* Argument is a scalar, not entirely passed in registers.
4158 (If part is passed in registers, arg->partial says how much
4159 and emit_push_insn will take care of putting it there.)
4161 Push it, and if its size is less than the
4162 amount of space allocated to it,
4163 also bump stack pointer by the additional space.
4164 Note that in C the default argument promotions
4165 will prevent such mismatches. */
4167 size
= GET_MODE_SIZE (arg
->mode
);
4168 /* Compute how much space the push instruction will push.
4169 On many machines, pushing a byte will advance the stack
4170 pointer by a halfword. */
4171 #ifdef PUSH_ROUNDING
4172 size
= PUSH_ROUNDING (size
);
4176 /* Compute how much space the argument should get:
4177 round up to a multiple of the alignment for arguments. */
4178 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4179 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4180 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4181 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4183 /* Compute the alignment of the pushed argument. */
4184 parm_align
= arg
->locate
.boundary
;
4185 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4187 int pad
= used
- size
;
4190 unsigned int pad_align
= (pad
& -pad
) * BITS_PER_UNIT
;
4191 parm_align
= MIN (parm_align
, pad_align
);
4195 /* This isn't already where we want it on the stack, so put it there.
4196 This can either be done with push or copy insns. */
4197 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
,
4198 parm_align
, partial
, reg
, used
- size
, argblock
,
4199 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4200 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4202 /* Unless this is a partially-in-register argument, the argument is now
4205 arg
->value
= arg
->stack
;
4209 /* BLKmode, at least partly to be pushed. */
4211 unsigned int parm_align
;
4215 /* Pushing a nonscalar.
4216 If part is passed in registers, PARTIAL says how much
4217 and emit_push_insn will take care of putting it there. */
4219 /* Round its size up to a multiple
4220 of the allocation unit for arguments. */
4222 if (arg
->locate
.size
.var
!= 0)
4225 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
4229 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4230 for BLKmode is careful to avoid it. */
4231 excess
= (arg
->locate
.size
.constant
4232 - int_size_in_bytes (TREE_TYPE (pval
))
4234 size_rtx
= expand_expr (size_in_bytes (TREE_TYPE (pval
)),
4235 NULL_RTX
, TYPE_MODE (sizetype
),
4239 parm_align
= arg
->locate
.boundary
;
4241 /* When an argument is padded down, the block is aligned to
4242 PARM_BOUNDARY, but the actual argument isn't. */
4243 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4245 if (arg
->locate
.size
.var
)
4246 parm_align
= BITS_PER_UNIT
;
4249 unsigned int excess_align
= (excess
& -excess
) * BITS_PER_UNIT
;
4250 parm_align
= MIN (parm_align
, excess_align
);
4254 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
4256 /* emit_push_insn might not work properly if arg->value and
4257 argblock + arg->locate.offset areas overlap. */
4261 if (XEXP (x
, 0) == crtl
->args
.internal_arg_pointer
4262 || (GET_CODE (XEXP (x
, 0)) == PLUS
4263 && XEXP (XEXP (x
, 0), 0) ==
4264 crtl
->args
.internal_arg_pointer
4265 && CONST_INT_P (XEXP (XEXP (x
, 0), 1))))
4267 if (XEXP (x
, 0) != crtl
->args
.internal_arg_pointer
)
4268 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4270 /* expand_call should ensure this. */
4271 gcc_assert (!arg
->locate
.offset
.var
4272 && arg
->locate
.size
.var
== 0
4273 && CONST_INT_P (size_rtx
));
4275 if (arg
->locate
.offset
.constant
> i
)
4277 if (arg
->locate
.offset
.constant
< i
+ INTVAL (size_rtx
))
4278 sibcall_failure
= 1;
4280 else if (arg
->locate
.offset
.constant
< i
)
4282 /* Use arg->locate.size.constant instead of size_rtx
4283 because we only care about the part of the argument
4285 if (i
< (arg
->locate
.offset
.constant
4286 + arg
->locate
.size
.constant
))
4287 sibcall_failure
= 1;
4291 /* Even though they appear to be at the same location,
4292 if part of the outgoing argument is in registers,
4293 they aren't really at the same location. Check for
4294 this by making sure that the incoming size is the
4295 same as the outgoing size. */
4296 if (arg
->locate
.size
.constant
!= INTVAL (size_rtx
))
4297 sibcall_failure
= 1;
4302 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4303 parm_align
, partial
, reg
, excess
, argblock
,
4304 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4305 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4307 /* Unless this is a partially-in-register argument, the argument is now
4310 ??? Unlike the case above, in which we want the actual
4311 address of the data, so that we can load it directly into a
4312 register, here we want the address of the stack slot, so that
4313 it's properly aligned for word-by-word copying or something
4314 like that. It's not clear that this is always correct. */
4316 arg
->value
= arg
->stack_slot
;
4319 if (arg
->reg
&& GET_CODE (arg
->reg
) == PARALLEL
)
4321 tree type
= TREE_TYPE (arg
->tree_value
);
4323 = emit_group_load_into_temps (arg
->reg
, arg
->value
, type
,
4324 int_size_in_bytes (type
));
4327 /* Mark all slots this store used. */
4328 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
4329 && argblock
&& ! variable_size
&& arg
->stack
)
4330 for (i
= lower_bound
; i
< upper_bound
; i
++)
4331 stack_usage_map
[i
] = 1;
4333 /* Once we have pushed something, pops can't safely
4334 be deferred during the rest of the arguments. */
4337 /* Free any temporary slots made in processing this argument. Show
4338 that we might have taken the address of something and pushed that
4340 preserve_temp_slots (NULL_RTX
);
4344 return sibcall_failure
;
4347 /* Nonzero if we do not know how to pass TYPE solely in registers. */
4350 must_pass_in_stack_var_size (enum machine_mode mode ATTRIBUTE_UNUSED
,
4356 /* If the type has variable size... */
4357 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4360 /* If the type is marked as addressable (it is required
4361 to be constructed into the stack)... */
4362 if (TREE_ADDRESSABLE (type
))
4368 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
4369 takes trailing padding of a structure into account. */
4370 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
4373 must_pass_in_stack_var_size_or_pad (enum machine_mode mode
, const_tree type
)
4378 /* If the type has variable size... */
4379 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4382 /* If the type is marked as addressable (it is required
4383 to be constructed into the stack)... */
4384 if (TREE_ADDRESSABLE (type
))
4387 /* If the padding and mode of the type is such that a copy into
4388 a register would put it into the wrong part of the register. */
4390 && int_size_in_bytes (type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
4391 && (FUNCTION_ARG_PADDING (mode
, type
)
4392 == (BYTES_BIG_ENDIAN
? upward
: downward
)))