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 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
24 #include "coretypes.h"
39 #include "langhooks.h"
44 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
45 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
47 /* Data structure and subroutines used within expand_call. */
51 /* Tree node for this argument. */
53 /* Mode for value; TYPE_MODE unless promoted. */
54 enum machine_mode mode
;
55 /* Current RTL value for argument, or 0 if it isn't precomputed. */
57 /* Initially-compute RTL value for argument; only for const functions. */
59 /* Register to pass this argument in, 0 if passed on stack, or an
60 PARALLEL if the arg is to be copied into multiple non-contiguous
63 /* Register to pass this argument in when generating tail call sequence.
64 This is not the same register as for normal calls on machines with
67 /* If REG was promoted from the actual mode of the argument expression,
68 indicates whether the promotion is sign- or zero-extended. */
70 /* Number of registers to use. 0 means put the whole arg in registers.
71 Also 0 if not passed in registers. */
73 /* Nonzero if argument must be passed on stack.
74 Note that some arguments may be passed on the stack
75 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
76 pass_on_stack identifies arguments that *cannot* go in registers. */
78 /* Some fields packaged up for locate_and_pad_parm. */
79 struct locate_and_pad_arg_data locate
;
80 /* Location on the stack at which parameter should be stored. The store
81 has already been done if STACK == VALUE. */
83 /* Location on the stack of the start of this argument slot. This can
84 differ from STACK if this arg pads downward. This location is known
85 to be aligned to FUNCTION_ARG_BOUNDARY. */
87 /* Place that this stack area has been saved, if needed. */
89 /* If an argument's alignment does not permit direct copying into registers,
90 copy in smaller-sized pieces into pseudos. These are stored in a
91 block pointed to by this field. The next field says how many
92 word-sized pseudos we made. */
97 /* A vector of one char per byte of stack space. A byte if nonzero if
98 the corresponding stack location has been used.
99 This vector is used to prevent a function call within an argument from
100 clobbering any stack already set up. */
101 static char *stack_usage_map
;
103 /* Size of STACK_USAGE_MAP. */
104 static int highest_outgoing_arg_in_use
;
106 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
107 stack location's tail call argument has been already stored into the stack.
108 This bitmap is used to prevent sibling call optimization if function tries
109 to use parent's incoming argument slots when they have been already
110 overwritten with tail call arguments. */
111 static sbitmap stored_args_map
;
113 /* stack_arg_under_construction is nonzero when an argument may be
114 initialized with a constructor call (including a C function that
115 returns a BLKmode struct) and expand_call must take special action
116 to make sure the object being constructed does not overlap the
117 argument list for the constructor call. */
118 int stack_arg_under_construction
;
120 static void emit_call_1 (rtx
, tree
, tree
, tree
, HOST_WIDE_INT
, HOST_WIDE_INT
,
121 HOST_WIDE_INT
, rtx
, rtx
, int, rtx
, int,
123 static void precompute_register_parameters (int, struct arg_data
*, int *);
124 static int store_one_arg (struct arg_data
*, rtx
, int, int, int);
125 static void store_unaligned_arguments_into_pseudos (struct arg_data
*, int);
126 static int finalize_must_preallocate (int, int, struct arg_data
*,
128 static void precompute_arguments (int, int, struct arg_data
*);
129 static int compute_argument_block_size (int, struct args_size
*, int);
130 static void initialize_argument_information (int, struct arg_data
*,
131 struct args_size
*, int, tree
,
132 tree
, CUMULATIVE_ARGS
*, int,
133 rtx
*, int *, int *, int *,
135 static void compute_argument_addresses (struct arg_data
*, rtx
, int);
136 static rtx
rtx_for_function_call (tree
, tree
);
137 static void load_register_parameters (struct arg_data
*, int, rtx
*, int,
139 static rtx
emit_library_call_value_1 (int, rtx
, rtx
, enum libcall_type
,
140 enum machine_mode
, int, va_list);
141 static int special_function_p (tree
, int);
142 static int check_sibcall_argument_overlap_1 (rtx
);
143 static int check_sibcall_argument_overlap (rtx
, struct arg_data
*, int);
145 static int combine_pending_stack_adjustment_and_call (int, struct args_size
*,
147 static bool shift_returned_value (tree
, rtx
*);
149 #ifdef REG_PARM_STACK_SPACE
150 static rtx
save_fixed_argument_area (int, rtx
, int *, int *);
151 static void restore_fixed_argument_area (rtx
, rtx
, int, int);
154 /* Force FUNEXP into a form suitable for the address of a CALL,
155 and return that as an rtx. Also load the static chain register
156 if FNDECL is a nested function.
158 CALL_FUSAGE points to a variable holding the prospective
159 CALL_INSN_FUNCTION_USAGE information. */
162 prepare_call_address (rtx funexp
, rtx static_chain_value
,
163 rtx
*call_fusage
, int reg_parm_seen
, int sibcallp
)
165 /* Make a valid memory address and copy constants through pseudo-regs,
166 but not for a constant address if -fno-function-cse. */
167 if (GET_CODE (funexp
) != SYMBOL_REF
)
168 /* If we are using registers for parameters, force the
169 function address into a register now. */
170 funexp
= ((SMALL_REGISTER_CLASSES
&& reg_parm_seen
)
171 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
172 : memory_address (FUNCTION_MODE
, funexp
));
175 #ifndef NO_FUNCTION_CSE
176 if (optimize
&& ! flag_no_function_cse
)
177 funexp
= force_reg (Pmode
, funexp
);
181 if (static_chain_value
!= 0)
183 static_chain_value
= convert_memory_address (Pmode
, static_chain_value
);
184 emit_move_insn (static_chain_rtx
, static_chain_value
);
186 if (REG_P (static_chain_rtx
))
187 use_reg (call_fusage
, static_chain_rtx
);
193 /* Generate instructions to call function FUNEXP,
194 and optionally pop the results.
195 The CALL_INSN is the first insn generated.
197 FNDECL is the declaration node of the function. This is given to the
198 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
200 FUNTYPE is the data type of the function. This is given to the macro
201 RETURN_POPS_ARGS to determine whether this function pops its own args.
202 We used to allow an identifier for library functions, but that doesn't
203 work when the return type is an aggregate type and the calling convention
204 says that the pointer to this aggregate is to be popped by the callee.
206 STACK_SIZE is the number of bytes of arguments on the stack,
207 ROUNDED_STACK_SIZE is that number rounded up to
208 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
209 both to put into the call insn and to generate explicit popping
212 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
213 It is zero if this call doesn't want a structure value.
215 NEXT_ARG_REG is the rtx that results from executing
216 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
217 just after all the args have had their registers assigned.
218 This could be whatever you like, but normally it is the first
219 arg-register beyond those used for args in this call,
220 or 0 if all the arg-registers are used in this call.
221 It is passed on to `gen_call' so you can put this info in the call insn.
223 VALREG is a hard register in which a value is returned,
224 or 0 if the call does not return a value.
226 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
227 the args to this call were processed.
228 We restore `inhibit_defer_pop' to that value.
230 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
231 denote registers used by the called function. */
234 emit_call_1 (rtx funexp
, tree fntree
, tree fndecl ATTRIBUTE_UNUSED
,
235 tree funtype ATTRIBUTE_UNUSED
,
236 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED
,
237 HOST_WIDE_INT rounded_stack_size
,
238 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED
,
239 rtx next_arg_reg ATTRIBUTE_UNUSED
, rtx valreg
,
240 int old_inhibit_defer_pop
, rtx call_fusage
, int ecf_flags
,
241 CUMULATIVE_ARGS
*args_so_far ATTRIBUTE_UNUSED
)
243 rtx rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
245 int already_popped
= 0;
246 HOST_WIDE_INT n_popped
= RETURN_POPS_ARGS (fndecl
, funtype
, stack_size
);
247 #if defined (HAVE_call) && defined (HAVE_call_value)
248 rtx struct_value_size_rtx
;
249 struct_value_size_rtx
= GEN_INT (struct_value_size
);
252 #ifdef CALL_POPS_ARGS
253 n_popped
+= CALL_POPS_ARGS (* args_so_far
);
256 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
257 and we don't want to load it into a register as an optimization,
258 because prepare_call_address already did it if it should be done. */
259 if (GET_CODE (funexp
) != SYMBOL_REF
)
260 funexp
= memory_address (FUNCTION_MODE
, funexp
);
262 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
263 if ((ecf_flags
& ECF_SIBCALL
)
264 && HAVE_sibcall_pop
&& HAVE_sibcall_value_pop
265 && (n_popped
> 0 || stack_size
== 0))
267 rtx n_pop
= GEN_INT (n_popped
);
270 /* If this subroutine pops its own args, record that in the call insn
271 if possible, for the sake of frame pointer elimination. */
274 pat
= GEN_SIBCALL_VALUE_POP (valreg
,
275 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
276 rounded_stack_size_rtx
, next_arg_reg
,
279 pat
= GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
280 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
282 emit_call_insn (pat
);
288 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
289 /* If the target has "call" or "call_value" insns, then prefer them
290 if no arguments are actually popped. If the target does not have
291 "call" or "call_value" insns, then we must use the popping versions
292 even if the call has no arguments to pop. */
293 #if defined (HAVE_call) && defined (HAVE_call_value)
294 if (HAVE_call
&& HAVE_call_value
&& HAVE_call_pop
&& HAVE_call_value_pop
295 && n_popped
> 0 && ! (ecf_flags
& ECF_SP_DEPRESSED
))
297 if (HAVE_call_pop
&& HAVE_call_value_pop
)
300 rtx n_pop
= GEN_INT (n_popped
);
303 /* If this subroutine pops its own args, record that in the call insn
304 if possible, for the sake of frame pointer elimination. */
307 pat
= GEN_CALL_VALUE_POP (valreg
,
308 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
309 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
311 pat
= GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
312 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
314 emit_call_insn (pat
);
320 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
321 if ((ecf_flags
& ECF_SIBCALL
)
322 && HAVE_sibcall
&& HAVE_sibcall_value
)
325 emit_call_insn (GEN_SIBCALL_VALUE (valreg
,
326 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
327 rounded_stack_size_rtx
,
328 next_arg_reg
, NULL_RTX
));
330 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
331 rounded_stack_size_rtx
, next_arg_reg
,
332 struct_value_size_rtx
));
337 #if defined (HAVE_call) && defined (HAVE_call_value)
338 if (HAVE_call
&& HAVE_call_value
)
341 emit_call_insn (GEN_CALL_VALUE (valreg
,
342 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
343 rounded_stack_size_rtx
, next_arg_reg
,
346 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
347 rounded_stack_size_rtx
, next_arg_reg
,
348 struct_value_size_rtx
));
354 /* Find the call we just emitted. */
355 call_insn
= last_call_insn ();
357 /* Mark memory as used for "pure" function call. */
358 if (ecf_flags
& ECF_PURE
)
362 gen_rtx_USE (VOIDmode
,
363 gen_rtx_MEM (BLKmode
, gen_rtx_SCRATCH (VOIDmode
))),
366 /* Put the register usage information there. */
367 add_function_usage_to (call_insn
, call_fusage
);
369 /* If this is a const call, then set the insn's unchanging bit. */
370 if (ecf_flags
& (ECF_CONST
| ECF_PURE
))
371 CONST_OR_PURE_CALL_P (call_insn
) = 1;
373 /* If this call can't throw, attach a REG_EH_REGION reg note to that
375 if (ecf_flags
& ECF_NOTHROW
)
376 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_EH_REGION
, const0_rtx
,
377 REG_NOTES (call_insn
));
380 int rn
= lookup_stmt_eh_region (fntree
);
382 /* If rn < 0, then either (1) tree-ssa not used or (2) doesn't
383 throw, which we already took care of. */
385 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_EH_REGION
, GEN_INT (rn
),
386 REG_NOTES (call_insn
));
387 note_current_region_may_contain_throw ();
390 if (ecf_flags
& ECF_NORETURN
)
391 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_NORETURN
, const0_rtx
,
392 REG_NOTES (call_insn
));
393 if (ecf_flags
& ECF_ALWAYS_RETURN
)
394 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN
, const0_rtx
,
395 REG_NOTES (call_insn
));
397 if (ecf_flags
& ECF_RETURNS_TWICE
)
399 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_SETJMP
, const0_rtx
,
400 REG_NOTES (call_insn
));
401 current_function_calls_setjmp
= 1;
404 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
406 /* Restore this now, so that we do defer pops for this call's args
407 if the context of the call as a whole permits. */
408 inhibit_defer_pop
= old_inhibit_defer_pop
;
413 CALL_INSN_FUNCTION_USAGE (call_insn
)
414 = gen_rtx_EXPR_LIST (VOIDmode
,
415 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
416 CALL_INSN_FUNCTION_USAGE (call_insn
));
417 rounded_stack_size
-= n_popped
;
418 rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
419 stack_pointer_delta
-= n_popped
;
422 if (!ACCUMULATE_OUTGOING_ARGS
)
424 /* If returning from the subroutine does not automatically pop the args,
425 we need an instruction to pop them sooner or later.
426 Perhaps do it now; perhaps just record how much space to pop later.
428 If returning from the subroutine does pop the args, indicate that the
429 stack pointer will be changed. */
431 if (rounded_stack_size
!= 0)
433 if (ecf_flags
& (ECF_SP_DEPRESSED
| ECF_NORETURN
| ECF_LONGJMP
))
434 /* Just pretend we did the pop. */
435 stack_pointer_delta
-= rounded_stack_size
;
436 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
437 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
438 pending_stack_adjust
+= rounded_stack_size
;
440 adjust_stack (rounded_stack_size_rtx
);
443 /* When we accumulate outgoing args, we must avoid any stack manipulations.
444 Restore the stack pointer to its original value now. Usually
445 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
446 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
447 popping variants of functions exist as well.
449 ??? We may optimize similar to defer_pop above, but it is
450 probably not worthwhile.
452 ??? It will be worthwhile to enable combine_stack_adjustments even for
455 anti_adjust_stack (GEN_INT (n_popped
));
458 /* Determine if the function identified by NAME and FNDECL is one with
459 special properties we wish to know about.
461 For example, if the function might return more than one time (setjmp), then
462 set RETURNS_TWICE to a nonzero value.
464 Similarly set LONGJMP for if the function is in the longjmp family.
466 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
467 space from the stack such as alloca. */
470 special_function_p (tree fndecl
, int flags
)
472 if (fndecl
&& DECL_NAME (fndecl
)
473 && IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) <= 17
474 /* Exclude functions not at the file scope, or not `extern',
475 since they are not the magic functions we would otherwise
477 FIXME: this should be handled with attributes, not with this
478 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
479 because you can declare fork() inside a function if you
481 && (DECL_CONTEXT (fndecl
) == NULL_TREE
482 || TREE_CODE (DECL_CONTEXT (fndecl
)) == TRANSLATION_UNIT_DECL
)
483 && TREE_PUBLIC (fndecl
))
485 const char *name
= IDENTIFIER_POINTER (DECL_NAME (fndecl
));
486 const char *tname
= name
;
488 /* We assume that alloca will always be called by name. It
489 makes no sense to pass it as a pointer-to-function to
490 anything that does not understand its behavior. */
491 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 6
493 && ! strcmp (name
, "alloca"))
494 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 16
496 && ! strcmp (name
, "__builtin_alloca"))))
497 flags
|= ECF_MAY_BE_ALLOCA
;
499 /* Disregard prefix _, __ or __x. */
502 if (name
[1] == '_' && name
[2] == 'x')
504 else if (name
[1] == '_')
513 && (! strcmp (tname
, "setjmp")
514 || ! strcmp (tname
, "setjmp_syscall")))
516 && ! strcmp (tname
, "sigsetjmp"))
518 && ! strcmp (tname
, "savectx")))
519 flags
|= ECF_RETURNS_TWICE
;
522 && ! strcmp (tname
, "siglongjmp"))
523 flags
|= ECF_LONGJMP
;
525 else if ((tname
[0] == 'q' && tname
[1] == 's'
526 && ! strcmp (tname
, "qsetjmp"))
527 || (tname
[0] == 'v' && tname
[1] == 'f'
528 && ! strcmp (tname
, "vfork")))
529 flags
|= ECF_RETURNS_TWICE
;
531 else if (tname
[0] == 'l' && tname
[1] == 'o'
532 && ! strcmp (tname
, "longjmp"))
533 flags
|= ECF_LONGJMP
;
539 /* Return nonzero when tree represent call to longjmp. */
542 setjmp_call_p (tree fndecl
)
544 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
547 /* Return true when exp contains alloca call. */
549 alloca_call_p (tree exp
)
551 if (TREE_CODE (exp
) == CALL_EXPR
552 && TREE_CODE (TREE_OPERAND (exp
, 0)) == ADDR_EXPR
553 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0))
555 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0),
556 0) & ECF_MAY_BE_ALLOCA
))
561 /* Detect flags (function attributes) from the function decl or type node. */
564 flags_from_decl_or_type (tree exp
)
571 struct cgraph_rtl_info
*i
= cgraph_rtl_info (exp
);
572 type
= TREE_TYPE (exp
);
576 if (i
->pure_function
)
577 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
578 if (i
->const_function
)
579 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
582 /* The function exp may have the `malloc' attribute. */
583 if (DECL_IS_MALLOC (exp
))
586 /* The function exp may have the `pure' attribute. */
587 if (DECL_IS_PURE (exp
))
588 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
590 if (TREE_NOTHROW (exp
))
591 flags
|= ECF_NOTHROW
;
593 if (TREE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
594 flags
|= ECF_LIBCALL_BLOCK
| ECF_CONST
;
596 flags
= special_function_p (exp
, flags
);
598 else if (TYPE_P (exp
) && TYPE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
601 if (TREE_THIS_VOLATILE (exp
))
602 flags
|= ECF_NORETURN
;
604 /* Mark if the function returns with the stack pointer depressed. We
605 cannot consider it pure or constant in that case. */
606 if (TREE_CODE (type
) == FUNCTION_TYPE
&& TYPE_RETURNS_STACK_DEPRESSED (type
))
608 flags
|= ECF_SP_DEPRESSED
;
609 flags
&= ~(ECF_PURE
| ECF_CONST
| ECF_LIBCALL_BLOCK
);
615 /* Detect flags from a CALL_EXPR. */
618 call_expr_flags (tree t
)
621 tree decl
= get_callee_fndecl (t
);
624 flags
= flags_from_decl_or_type (decl
);
627 t
= TREE_TYPE (TREE_OPERAND (t
, 0));
628 if (t
&& TREE_CODE (t
) == POINTER_TYPE
)
629 flags
= flags_from_decl_or_type (TREE_TYPE (t
));
637 /* Precompute all register parameters as described by ARGS, storing values
638 into fields within the ARGS array.
640 NUM_ACTUALS indicates the total number elements in the ARGS array.
642 Set REG_PARM_SEEN if we encounter a register parameter. */
645 precompute_register_parameters (int num_actuals
, struct arg_data
*args
, int *reg_parm_seen
)
651 for (i
= 0; i
< num_actuals
; i
++)
652 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
656 if (args
[i
].value
== 0)
659 args
[i
].value
= expand_expr (args
[i
].tree_value
, NULL_RTX
,
661 preserve_temp_slots (args
[i
].value
);
665 /* If the value is a non-legitimate constant, force it into a
666 pseudo now. TLS symbols sometimes need a call to resolve. */
667 if (CONSTANT_P (args
[i
].value
)
668 && !LEGITIMATE_CONSTANT_P (args
[i
].value
))
669 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
671 /* If we are to promote the function arg to a wider mode,
674 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
676 = convert_modes (args
[i
].mode
,
677 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
678 args
[i
].value
, args
[i
].unsignedp
);
680 /* If the value is expensive, and we are inside an appropriately
681 short loop, put the value into a pseudo and then put the pseudo
684 For small register classes, also do this if this call uses
685 register parameters. This is to avoid reload conflicts while
686 loading the parameters registers. */
688 if ((! (REG_P (args
[i
].value
)
689 || (GET_CODE (args
[i
].value
) == SUBREG
690 && REG_P (SUBREG_REG (args
[i
].value
)))))
691 && args
[i
].mode
!= BLKmode
692 && rtx_cost (args
[i
].value
, SET
) > COSTS_N_INSNS (1)
693 && ((SMALL_REGISTER_CLASSES
&& *reg_parm_seen
)
694 || preserve_subexpressions_p ()))
695 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
699 #ifdef REG_PARM_STACK_SPACE
701 /* The argument list is the property of the called routine and it
702 may clobber it. If the fixed area has been used for previous
703 parameters, we must save and restore it. */
706 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
711 /* Compute the boundary of the area that needs to be saved, if any. */
712 high
= reg_parm_stack_space
;
713 #ifdef ARGS_GROW_DOWNWARD
716 if (high
> highest_outgoing_arg_in_use
)
717 high
= highest_outgoing_arg_in_use
;
719 for (low
= 0; low
< high
; low
++)
720 if (stack_usage_map
[low
] != 0)
723 enum machine_mode save_mode
;
728 while (stack_usage_map
[--high
] == 0)
732 *high_to_save
= high
;
734 num_to_save
= high
- low
+ 1;
735 save_mode
= mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
737 /* If we don't have the required alignment, must do this
739 if ((low
& (MIN (GET_MODE_SIZE (save_mode
),
740 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
743 #ifdef ARGS_GROW_DOWNWARD
748 stack_area
= gen_rtx_MEM (save_mode
,
749 memory_address (save_mode
,
750 plus_constant (argblock
,
753 set_mem_align (stack_area
, PARM_BOUNDARY
);
754 if (save_mode
== BLKmode
)
756 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
757 emit_block_move (validize_mem (save_area
), stack_area
,
758 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
762 save_area
= gen_reg_rtx (save_mode
);
763 emit_move_insn (save_area
, stack_area
);
773 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
775 enum machine_mode save_mode
= GET_MODE (save_area
);
779 #ifdef ARGS_GROW_DOWNWARD
780 delta
= -high_to_save
;
784 stack_area
= gen_rtx_MEM (save_mode
,
785 memory_address (save_mode
,
786 plus_constant (argblock
, delta
)));
787 set_mem_align (stack_area
, PARM_BOUNDARY
);
789 if (save_mode
!= BLKmode
)
790 emit_move_insn (stack_area
, save_area
);
792 emit_block_move (stack_area
, validize_mem (save_area
),
793 GEN_INT (high_to_save
- low_to_save
+ 1),
796 #endif /* REG_PARM_STACK_SPACE */
798 /* If any elements in ARGS refer to parameters that are to be passed in
799 registers, but not in memory, and whose alignment does not permit a
800 direct copy into registers. Copy the values into a group of pseudos
801 which we will later copy into the appropriate hard registers.
803 Pseudos for each unaligned argument will be stored into the array
804 args[argnum].aligned_regs. The caller is responsible for deallocating
805 the aligned_regs array if it is nonzero. */
808 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
812 for (i
= 0; i
< num_actuals
; i
++)
813 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
814 && args
[i
].mode
== BLKmode
815 && (TYPE_ALIGN (TREE_TYPE (args
[i
].tree_value
))
816 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
818 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
819 int nregs
= (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
820 int endian_correction
= 0;
822 args
[i
].n_aligned_regs
= args
[i
].partial
? args
[i
].partial
: nregs
;
823 args
[i
].aligned_regs
= xmalloc (sizeof (rtx
) * args
[i
].n_aligned_regs
);
825 /* Structures smaller than a word are normally aligned to the
826 least significant byte. On a BYTES_BIG_ENDIAN machine,
827 this means we must skip the empty high order bytes when
828 calculating the bit offset. */
829 if (bytes
< UNITS_PER_WORD
830 #ifdef BLOCK_REG_PADDING
831 && (BLOCK_REG_PADDING (args
[i
].mode
,
832 TREE_TYPE (args
[i
].tree_value
), 1)
838 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
840 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
842 rtx reg
= gen_reg_rtx (word_mode
);
843 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
844 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
846 args
[i
].aligned_regs
[j
] = reg
;
847 word
= extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
848 word_mode
, word_mode
);
850 /* There is no need to restrict this code to loading items
851 in TYPE_ALIGN sized hunks. The bitfield instructions can
852 load up entire word sized registers efficiently.
854 ??? This may not be needed anymore.
855 We use to emit a clobber here but that doesn't let later
856 passes optimize the instructions we emit. By storing 0 into
857 the register later passes know the first AND to zero out the
858 bitfield being set in the register is unnecessary. The store
859 of 0 will be deleted as will at least the first AND. */
861 emit_move_insn (reg
, const0_rtx
);
863 bytes
-= bitsize
/ BITS_PER_UNIT
;
864 store_bit_field (reg
, bitsize
, endian_correction
, word_mode
,
870 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
873 NUM_ACTUALS is the total number of parameters.
875 N_NAMED_ARGS is the total number of named arguments.
877 FNDECL is the tree code for the target of this call (if known)
879 ARGS_SO_FAR holds state needed by the target to know where to place
882 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
883 for arguments which are passed in registers.
885 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
886 and may be modified by this routine.
888 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
889 flags which may may be modified by this routine.
891 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
892 that requires allocation of stack space.
894 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
895 the thunked-to function. */
898 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
899 struct arg_data
*args
,
900 struct args_size
*args_size
,
901 int n_named_args ATTRIBUTE_UNUSED
,
902 tree actparms
, tree fndecl
,
903 CUMULATIVE_ARGS
*args_so_far
,
904 int reg_parm_stack_space
,
905 rtx
*old_stack_level
, int *old_pending_adj
,
906 int *must_preallocate
, int *ecf_flags
,
907 bool *may_tailcall
, bool call_from_thunk_p
)
909 /* 1 if scanning parms front to back, -1 if scanning back to front. */
912 /* Count arg position in order args appear. */
918 args_size
->constant
= 0;
921 /* In this loop, we consider args in the order they are written.
922 We fill up ARGS from the front or from the back if necessary
923 so that in any case the first arg to be pushed ends up at the front. */
925 if (PUSH_ARGS_REVERSED
)
927 i
= num_actuals
- 1, inc
= -1;
928 /* In this case, must reverse order of args
929 so that we compute and push the last arg first. */
936 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
937 for (p
= actparms
, argpos
= 0; p
; p
= TREE_CHAIN (p
), i
+= inc
, argpos
++)
939 tree type
= TREE_TYPE (TREE_VALUE (p
));
941 enum machine_mode mode
;
943 args
[i
].tree_value
= TREE_VALUE (p
);
945 /* Replace erroneous argument with constant zero. */
946 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
947 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
949 /* If TYPE is a transparent union, pass things the way we would
950 pass the first field of the union. We have already verified that
951 the modes are the same. */
952 if (TREE_CODE (type
) == UNION_TYPE
&& TYPE_TRANSPARENT_UNION (type
))
953 type
= TREE_TYPE (TYPE_FIELDS (type
));
955 /* Decide where to pass this arg.
957 args[i].reg is nonzero if all or part is passed in registers.
959 args[i].partial is nonzero if part but not all is passed in registers,
960 and the exact value says how many words are passed in registers.
962 args[i].pass_on_stack is nonzero if the argument must at least be
963 computed on the stack. It may then be loaded back into registers
964 if args[i].reg is nonzero.
966 These decisions are driven by the FUNCTION_... macros and must agree
967 with those made by function.c. */
969 /* See if this argument should be passed by invisible reference. */
970 if (pass_by_reference (args_so_far
, TYPE_MODE (type
),
971 type
, argpos
< n_named_args
))
973 /* If we're compiling a thunk, pass through invisible
974 references instead of making a copy. */
975 if (call_from_thunk_p
976 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far
, TYPE_MODE (type
),
977 type
, argpos
< n_named_args
)
978 /* If it's in a register, we must make a copy of it too. */
979 /* ??? Is this a sufficient test? Is there a better one? */
980 && !(TREE_CODE (args
[i
].tree_value
) == VAR_DECL
981 && REG_P (DECL_RTL (args
[i
].tree_value
)))
982 && ! TREE_ADDRESSABLE (type
))
985 /* C++ uses a TARGET_EXPR to indicate that we want to make a
986 new object from the argument. If we are passing by
987 invisible reference, the callee will do that for us, so we
988 can strip off the TARGET_EXPR. This is not always safe,
989 but it is safe in the only case where this is a useful
990 optimization; namely, when the argument is a plain object.
991 In that case, the frontend is just asking the backend to
992 make a bitwise copy of the argument. */
994 if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
995 && (DECL_P (TREE_OPERAND (args
[i
].tree_value
, 1)))
996 && ! REG_P (DECL_RTL (TREE_OPERAND (args
[i
].tree_value
, 1))))
997 args
[i
].tree_value
= TREE_OPERAND (args
[i
].tree_value
, 1);
999 /* We can't use sibcalls if a callee-copied argument is stored
1000 in the current function's frame. */
1001 if (!call_from_thunk_p
1002 && (!DECL_P (args
[i
].tree_value
)
1003 || !TREE_STATIC (args
[i
].tree_value
)))
1004 *may_tailcall
= false;
1006 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1007 build_pointer_type (type
),
1008 args
[i
].tree_value
);
1009 type
= build_pointer_type (type
);
1011 else if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
)
1013 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1014 We implement this by passing the address of the temporary
1015 rather than expanding it into another allocated slot. */
1016 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1017 build_pointer_type (type
),
1018 args
[i
].tree_value
);
1019 type
= build_pointer_type (type
);
1020 *may_tailcall
= false;
1024 /* We make a copy of the object and pass the address to the
1025 function being called. */
1028 if (!COMPLETE_TYPE_P (type
)
1029 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1030 || (flag_stack_check
&& ! STACK_CHECK_BUILTIN
1031 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type
),
1032 STACK_CHECK_MAX_VAR_SIZE
))))
1034 /* This is a variable-sized object. Make space on the stack
1036 rtx size_rtx
= expr_size (TREE_VALUE (p
));
1038 if (*old_stack_level
== 0)
1040 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1041 *old_pending_adj
= pending_stack_adjust
;
1042 pending_stack_adjust
= 0;
1045 copy
= gen_rtx_MEM (BLKmode
,
1046 allocate_dynamic_stack_space
1047 (size_rtx
, NULL_RTX
, TYPE_ALIGN (type
)));
1048 set_mem_attributes (copy
, type
, 1);
1051 copy
= assign_temp (type
, 0, 1, 0);
1053 store_expr (args
[i
].tree_value
, copy
, 0);
1054 *ecf_flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
1056 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1057 build_pointer_type (type
),
1058 make_tree (type
, copy
));
1059 type
= build_pointer_type (type
);
1060 *may_tailcall
= false;
1064 mode
= TYPE_MODE (type
);
1065 unsignedp
= TYPE_UNSIGNED (type
);
1067 if (targetm
.calls
.promote_function_args (fndecl
? TREE_TYPE (fndecl
) : 0))
1068 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
1070 args
[i
].unsignedp
= unsignedp
;
1071 args
[i
].mode
= mode
;
1073 args
[i
].reg
= FUNCTION_ARG (*args_so_far
, mode
, type
,
1074 argpos
< n_named_args
);
1075 #ifdef FUNCTION_INCOMING_ARG
1076 /* If this is a sibling call and the machine has register windows, the
1077 register window has to be unwinded before calling the routine, so
1078 arguments have to go into the incoming registers. */
1079 args
[i
].tail_call_reg
= FUNCTION_INCOMING_ARG (*args_so_far
, mode
, type
,
1080 argpos
< n_named_args
);
1082 args
[i
].tail_call_reg
= args
[i
].reg
;
1087 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far
, mode
, type
,
1088 argpos
< n_named_args
);
1090 args
[i
].pass_on_stack
= targetm
.calls
.must_pass_in_stack (mode
, type
);
1092 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1093 it means that we are to pass this arg in the register(s) designated
1094 by the PARALLEL, but also to pass it in the stack. */
1095 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1096 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1097 args
[i
].pass_on_stack
= 1;
1099 /* If this is an addressable type, we must preallocate the stack
1100 since we must evaluate the object into its final location.
1102 If this is to be passed in both registers and the stack, it is simpler
1104 if (TREE_ADDRESSABLE (type
)
1105 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1106 *must_preallocate
= 1;
1108 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1109 we cannot consider this function call constant. */
1110 if (TREE_ADDRESSABLE (type
))
1111 *ecf_flags
&= ~ECF_LIBCALL_BLOCK
;
1113 /* Compute the stack-size of this argument. */
1114 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1115 || reg_parm_stack_space
> 0
1116 || args
[i
].pass_on_stack
)
1117 locate_and_pad_parm (mode
, type
,
1118 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1123 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
1124 fndecl
, args_size
, &args
[i
].locate
);
1125 #ifdef BLOCK_REG_PADDING
1127 /* The argument is passed entirely in registers. See at which
1128 end it should be padded. */
1129 args
[i
].locate
.where_pad
=
1130 BLOCK_REG_PADDING (mode
, type
,
1131 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
1134 /* Update ARGS_SIZE, the total stack space for args so far. */
1136 args_size
->constant
+= args
[i
].locate
.size
.constant
;
1137 if (args
[i
].locate
.size
.var
)
1138 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
1140 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1141 have been used, etc. */
1143 FUNCTION_ARG_ADVANCE (*args_so_far
, TYPE_MODE (type
), type
,
1144 argpos
< n_named_args
);
1148 /* Update ARGS_SIZE to contain the total size for the argument block.
1149 Return the original constant component of the argument block's size.
1151 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1152 for arguments passed in registers. */
1155 compute_argument_block_size (int reg_parm_stack_space
,
1156 struct args_size
*args_size
,
1157 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
1159 int unadjusted_args_size
= args_size
->constant
;
1161 /* For accumulate outgoing args mode we don't need to align, since the frame
1162 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1163 backends from generating misaligned frame sizes. */
1164 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1165 preferred_stack_boundary
= STACK_BOUNDARY
;
1167 /* Compute the actual size of the argument block required. The variable
1168 and constant sizes must be combined, the size may have to be rounded,
1169 and there may be a minimum required size. */
1173 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1174 args_size
->constant
= 0;
1176 preferred_stack_boundary
/= BITS_PER_UNIT
;
1177 if (preferred_stack_boundary
> 1)
1179 /* We don't handle this case yet. To handle it correctly we have
1180 to add the delta, round and subtract the delta.
1181 Currently no machine description requires this support. */
1182 if (stack_pointer_delta
& (preferred_stack_boundary
- 1))
1184 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1187 if (reg_parm_stack_space
> 0)
1190 = size_binop (MAX_EXPR
, args_size
->var
,
1191 ssize_int (reg_parm_stack_space
));
1193 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1194 /* The area corresponding to register parameters is not to count in
1195 the size of the block we need. So make the adjustment. */
1197 = size_binop (MINUS_EXPR
, args_size
->var
,
1198 ssize_int (reg_parm_stack_space
));
1204 preferred_stack_boundary
/= BITS_PER_UNIT
;
1205 if (preferred_stack_boundary
< 1)
1206 preferred_stack_boundary
= 1;
1207 args_size
->constant
= (((args_size
->constant
1208 + stack_pointer_delta
1209 + preferred_stack_boundary
- 1)
1210 / preferred_stack_boundary
1211 * preferred_stack_boundary
)
1212 - stack_pointer_delta
);
1214 args_size
->constant
= MAX (args_size
->constant
,
1215 reg_parm_stack_space
);
1217 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1218 args_size
->constant
-= reg_parm_stack_space
;
1221 return unadjusted_args_size
;
1224 /* Precompute parameters as needed for a function call.
1226 FLAGS is mask of ECF_* constants.
1228 NUM_ACTUALS is the number of arguments.
1230 ARGS is an array containing information for each argument; this
1231 routine fills in the INITIAL_VALUE and VALUE fields for each
1232 precomputed argument. */
1235 precompute_arguments (int flags
, int num_actuals
, struct arg_data
*args
)
1239 /* If this is a libcall, then precompute all arguments so that we do not
1240 get extraneous instructions emitted as part of the libcall sequence. */
1241 if ((flags
& ECF_LIBCALL_BLOCK
) == 0)
1244 for (i
= 0; i
< num_actuals
; i
++)
1246 enum machine_mode mode
;
1248 /* If this is an addressable type, we cannot pre-evaluate it. */
1249 if (TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
)))
1252 args
[i
].initial_value
= args
[i
].value
1253 = expand_expr (args
[i
].tree_value
, NULL_RTX
, VOIDmode
, 0);
1255 mode
= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
));
1256 if (mode
!= args
[i
].mode
)
1259 = convert_modes (args
[i
].mode
, mode
,
1260 args
[i
].value
, args
[i
].unsignedp
);
1261 #if defined(PROMOTE_FUNCTION_MODE) && !defined(PROMOTE_MODE)
1262 /* CSE will replace this only if it contains args[i].value
1263 pseudo, so convert it down to the declared mode using
1265 if (REG_P (args
[i
].value
)
1266 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
)
1268 args
[i
].initial_value
1269 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1270 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1271 SUBREG_PROMOTED_UNSIGNED_SET (args
[i
].initial_value
,
1279 /* Given the current state of MUST_PREALLOCATE and information about
1280 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1281 compute and return the final value for MUST_PREALLOCATE. */
1284 finalize_must_preallocate (int must_preallocate
, int num_actuals
, struct arg_data
*args
, struct args_size
*args_size
)
1286 /* See if we have or want to preallocate stack space.
1288 If we would have to push a partially-in-regs parm
1289 before other stack parms, preallocate stack space instead.
1291 If the size of some parm is not a multiple of the required stack
1292 alignment, we must preallocate.
1294 If the total size of arguments that would otherwise create a copy in
1295 a temporary (such as a CALL) is more than half the total argument list
1296 size, preallocation is faster.
1298 Another reason to preallocate is if we have a machine (like the m88k)
1299 where stack alignment is required to be maintained between every
1300 pair of insns, not just when the call is made. However, we assume here
1301 that such machines either do not have push insns (and hence preallocation
1302 would occur anyway) or the problem is taken care of with
1305 if (! must_preallocate
)
1307 int partial_seen
= 0;
1308 int copy_to_evaluate_size
= 0;
1311 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1313 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1315 else if (partial_seen
&& args
[i
].reg
== 0)
1316 must_preallocate
= 1;
1318 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1319 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1320 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1321 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1322 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1323 copy_to_evaluate_size
1324 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1327 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1328 && args_size
->constant
> 0)
1329 must_preallocate
= 1;
1331 return must_preallocate
;
1334 /* If we preallocated stack space, compute the address of each argument
1335 and store it into the ARGS array.
1337 We need not ensure it is a valid memory address here; it will be
1338 validized when it is used.
1340 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1343 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
1347 rtx arg_reg
= argblock
;
1348 int i
, arg_offset
= 0;
1350 if (GET_CODE (argblock
) == PLUS
)
1351 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1353 for (i
= 0; i
< num_actuals
; i
++)
1355 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
1356 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
1359 /* Skip this parm if it will not be passed on the stack. */
1360 if (! args
[i
].pass_on_stack
&& args
[i
].reg
!= 0)
1363 if (GET_CODE (offset
) == CONST_INT
)
1364 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1366 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1368 addr
= plus_constant (addr
, arg_offset
);
1369 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1370 set_mem_align (args
[i
].stack
, PARM_BOUNDARY
);
1371 set_mem_attributes (args
[i
].stack
,
1372 TREE_TYPE (args
[i
].tree_value
), 1);
1374 if (GET_CODE (slot_offset
) == CONST_INT
)
1375 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1377 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1379 addr
= plus_constant (addr
, arg_offset
);
1380 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1381 set_mem_align (args
[i
].stack_slot
, PARM_BOUNDARY
);
1382 set_mem_attributes (args
[i
].stack_slot
,
1383 TREE_TYPE (args
[i
].tree_value
), 1);
1385 /* Function incoming arguments may overlap with sibling call
1386 outgoing arguments and we cannot allow reordering of reads
1387 from function arguments with stores to outgoing arguments
1388 of sibling calls. */
1389 set_mem_alias_set (args
[i
].stack
, 0);
1390 set_mem_alias_set (args
[i
].stack_slot
, 0);
1395 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1396 in a call instruction.
1398 FNDECL is the tree node for the target function. For an indirect call
1399 FNDECL will be NULL_TREE.
1401 ADDR is the operand 0 of CALL_EXPR for this call. */
1404 rtx_for_function_call (tree fndecl
, tree addr
)
1408 /* Get the function to call, in the form of RTL. */
1411 /* If this is the first use of the function, see if we need to
1412 make an external definition for it. */
1413 if (! TREE_USED (fndecl
))
1415 assemble_external (fndecl
);
1416 TREE_USED (fndecl
) = 1;
1419 /* Get a SYMBOL_REF rtx for the function address. */
1420 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1423 /* Generate an rtx (probably a pseudo-register) for the address. */
1426 funexp
= expand_expr (addr
, NULL_RTX
, VOIDmode
, 0);
1427 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1432 /* Do the register loads required for any wholly-register parms or any
1433 parms which are passed both on the stack and in a register. Their
1434 expressions were already evaluated.
1436 Mark all register-parms as living through the call, putting these USE
1437 insns in the CALL_INSN_FUNCTION_USAGE field.
1439 When IS_SIBCALL, perform the check_sibcall_overlap_argument_overlap
1440 checking, setting *SIBCALL_FAILURE if appropriate. */
1443 load_register_parameters (struct arg_data
*args
, int num_actuals
,
1444 rtx
*call_fusage
, int flags
, int is_sibcall
,
1445 int *sibcall_failure
)
1449 for (i
= 0; i
< num_actuals
; i
++)
1451 rtx reg
= ((flags
& ECF_SIBCALL
)
1452 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1455 int partial
= args
[i
].partial
;
1458 rtx before_arg
= get_last_insn ();
1459 /* Set to non-negative if must move a word at a time, even if just
1460 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1461 we just use a normal move insn. This value can be zero if the
1462 argument is a zero size structure with no fields. */
1466 else if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
)
1468 size
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1469 nregs
= (size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1472 size
= GET_MODE_SIZE (args
[i
].mode
);
1474 /* Handle calls that pass values in multiple non-contiguous
1475 locations. The Irix 6 ABI has examples of this. */
1477 if (GET_CODE (reg
) == PARALLEL
)
1479 tree type
= TREE_TYPE (args
[i
].tree_value
);
1480 emit_group_load (reg
, args
[i
].value
, type
,
1481 int_size_in_bytes (type
));
1484 /* If simple case, just do move. If normal partial, store_one_arg
1485 has already loaded the register for us. In all other cases,
1486 load the register(s) from memory. */
1488 else if (nregs
== -1)
1490 emit_move_insn (reg
, args
[i
].value
);
1491 #ifdef BLOCK_REG_PADDING
1492 /* Handle case where we have a value that needs shifting
1493 up to the msb. eg. a QImode value and we're padding
1494 upward on a BYTES_BIG_ENDIAN machine. */
1495 if (size
< UNITS_PER_WORD
1496 && (args
[i
].locate
.where_pad
1497 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
1500 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1502 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1503 report the whole reg as used. Strictly speaking, the
1504 call only uses SIZE bytes at the msb end, but it doesn't
1505 seem worth generating rtl to say that. */
1506 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
1507 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
1508 build_int_cst (NULL_TREE
, FIXMEFORMAT
1512 emit_move_insn (reg
, x
);
1517 /* If we have pre-computed the values to put in the registers in
1518 the case of non-aligned structures, copy them in now. */
1520 else if (args
[i
].n_aligned_regs
!= 0)
1521 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1522 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1523 args
[i
].aligned_regs
[j
]);
1525 else if (partial
== 0 || args
[i
].pass_on_stack
)
1527 rtx mem
= validize_mem (args
[i
].value
);
1529 /* Handle a BLKmode that needs shifting. */
1530 if (nregs
== 1 && size
< UNITS_PER_WORD
1531 #ifdef BLOCK_REG_PADDING
1532 && args
[i
].locate
.where_pad
== downward
1538 rtx tem
= operand_subword_force (mem
, 0, args
[i
].mode
);
1539 rtx ri
= gen_rtx_REG (word_mode
, REGNO (reg
));
1540 rtx x
= gen_reg_rtx (word_mode
);
1541 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1542 enum tree_code dir
= BYTES_BIG_ENDIAN
? RSHIFT_EXPR
1545 emit_move_insn (x
, tem
);
1546 x
= expand_shift (dir
, word_mode
, x
,
1547 build_int_cst (NULL_TREE
, shift
, 0),
1550 emit_move_insn (ri
, x
);
1553 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
1556 /* When a parameter is a block, and perhaps in other cases, it is
1557 possible that it did a load from an argument slot that was
1558 already clobbered. */
1560 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
1561 *sibcall_failure
= 1;
1563 /* Handle calls that pass values in multiple non-contiguous
1564 locations. The Irix 6 ABI has examples of this. */
1565 if (GET_CODE (reg
) == PARALLEL
)
1566 use_group_regs (call_fusage
, reg
);
1567 else if (nregs
== -1)
1568 use_reg (call_fusage
, reg
);
1570 use_regs (call_fusage
, REGNO (reg
), nregs
== 0 ? 1 : nregs
);
1575 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1576 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1577 bytes, then we would need to push some additional bytes to pad the
1578 arguments. So, we compute an adjust to the stack pointer for an
1579 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1580 bytes. Then, when the arguments are pushed the stack will be perfectly
1581 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1582 be popped after the call. Returns the adjustment. */
1585 combine_pending_stack_adjustment_and_call (int unadjusted_args_size
,
1586 struct args_size
*args_size
,
1587 unsigned int preferred_unit_stack_boundary
)
1589 /* The number of bytes to pop so that the stack will be
1590 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1591 HOST_WIDE_INT adjustment
;
1592 /* The alignment of the stack after the arguments are pushed, if we
1593 just pushed the arguments without adjust the stack here. */
1594 unsigned HOST_WIDE_INT unadjusted_alignment
;
1596 unadjusted_alignment
1597 = ((stack_pointer_delta
+ unadjusted_args_size
)
1598 % preferred_unit_stack_boundary
);
1600 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1601 as possible -- leaving just enough left to cancel out the
1602 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1603 PENDING_STACK_ADJUST is non-negative, and congruent to
1604 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1606 /* Begin by trying to pop all the bytes. */
1607 unadjusted_alignment
1608 = (unadjusted_alignment
1609 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1610 adjustment
= pending_stack_adjust
;
1611 /* Push enough additional bytes that the stack will be aligned
1612 after the arguments are pushed. */
1613 if (preferred_unit_stack_boundary
> 1)
1615 if (unadjusted_alignment
> 0)
1616 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1618 adjustment
+= unadjusted_alignment
;
1621 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1622 bytes after the call. The right number is the entire
1623 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1624 by the arguments in the first place. */
1626 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1631 /* Scan X expression if it does not dereference any argument slots
1632 we already clobbered by tail call arguments (as noted in stored_args_map
1634 Return nonzero if X expression dereferences such argument slots,
1638 check_sibcall_argument_overlap_1 (rtx x
)
1648 code
= GET_CODE (x
);
1652 if (XEXP (x
, 0) == current_function_internal_arg_pointer
)
1654 else if (GET_CODE (XEXP (x
, 0)) == PLUS
1655 && XEXP (XEXP (x
, 0), 0) ==
1656 current_function_internal_arg_pointer
1657 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
)
1658 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
1662 #ifdef ARGS_GROW_DOWNWARD
1663 i
= -i
- GET_MODE_SIZE (GET_MODE (x
));
1666 for (k
= 0; k
< GET_MODE_SIZE (GET_MODE (x
)); k
++)
1667 if (i
+ k
< stored_args_map
->n_bits
1668 && TEST_BIT (stored_args_map
, i
+ k
))
1674 /* Scan all subexpressions. */
1675 fmt
= GET_RTX_FORMAT (code
);
1676 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
1680 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
1683 else if (*fmt
== 'E')
1685 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
1686 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
1693 /* Scan sequence after INSN if it does not dereference any argument slots
1694 we already clobbered by tail call arguments (as noted in stored_args_map
1695 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1696 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1697 should be 0). Return nonzero if sequence after INSN dereferences such argument
1698 slots, zero otherwise. */
1701 check_sibcall_argument_overlap (rtx insn
, struct arg_data
*arg
, int mark_stored_args_map
)
1705 if (insn
== NULL_RTX
)
1706 insn
= get_insns ();
1708 insn
= NEXT_INSN (insn
);
1710 for (; insn
; insn
= NEXT_INSN (insn
))
1712 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
1715 if (mark_stored_args_map
)
1717 #ifdef ARGS_GROW_DOWNWARD
1718 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
1720 low
= arg
->locate
.slot_offset
.constant
;
1723 for (high
= low
+ arg
->locate
.size
.constant
; low
< high
; low
++)
1724 SET_BIT (stored_args_map
, low
);
1726 return insn
!= NULL_RTX
;
1729 /* If function value *VALUE was returned at the most significant end of a
1730 register, shift it towards the least significant end and convert it to
1731 TYPE's mode. Return true and update *VALUE if some action was needed.
1733 TYPE is the type of the function's return value, which is known not
1734 to have mode BLKmode. */
1737 shift_returned_value (tree type
, rtx
*value
)
1739 if (targetm
.calls
.return_in_msb (type
))
1741 HOST_WIDE_INT shift
;
1743 shift
= (GET_MODE_BITSIZE (GET_MODE (*value
))
1744 - BITS_PER_UNIT
* int_size_in_bytes (type
));
1747 /* Shift the value into the low part of the register. */
1748 *value
= expand_binop (GET_MODE (*value
), lshr_optab
, *value
,
1749 GEN_INT (shift
), 0, 1, OPTAB_WIDEN
);
1751 /* Truncate it to the type's mode, or its integer equivalent.
1752 This is subject to TRULY_NOOP_TRUNCATION. */
1753 *value
= convert_to_mode (int_mode_for_mode (TYPE_MODE (type
)),
1756 /* Now convert it to the final form. */
1757 *value
= gen_lowpart (TYPE_MODE (type
), *value
);
1764 /* Remove all REG_EQUIV notes found in the insn chain. */
1767 purge_reg_equiv_notes (void)
1771 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1775 rtx note
= find_reg_note (insn
, REG_EQUIV
, 0);
1778 /* Remove the note and keep looking at the notes for
1780 remove_note (insn
, note
);
1788 /* Clear RTX_UNCHANGING_P flag of incoming argument MEMs. */
1791 purge_mem_unchanging_flag (rtx x
)
1800 code
= GET_CODE (x
);
1804 if (RTX_UNCHANGING_P (x
)
1805 && (XEXP (x
, 0) == current_function_internal_arg_pointer
1806 || (GET_CODE (XEXP (x
, 0)) == PLUS
1807 && XEXP (XEXP (x
, 0), 0) ==
1808 current_function_internal_arg_pointer
1809 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
)))
1810 RTX_UNCHANGING_P (x
) = 0;
1814 /* Scan all subexpressions. */
1815 fmt
= GET_RTX_FORMAT (code
);
1816 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
1819 purge_mem_unchanging_flag (XEXP (x
, i
));
1820 else if (*fmt
== 'E')
1821 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
1822 purge_mem_unchanging_flag (XVECEXP (x
, i
, j
));
1827 /* Generate all the code for a function call
1828 and return an rtx for its value.
1829 Store the value in TARGET (specified as an rtx) if convenient.
1830 If the value is stored in TARGET then TARGET is returned.
1831 If IGNORE is nonzero, then we ignore the value of the function call. */
1834 expand_call (tree exp
, rtx target
, int ignore
)
1836 /* Nonzero if we are currently expanding a call. */
1837 static int currently_expanding_call
= 0;
1839 /* List of actual parameters. */
1840 tree actparms
= TREE_OPERAND (exp
, 1);
1841 /* RTX for the function to be called. */
1843 /* Sequence of insns to perform a normal "call". */
1844 rtx normal_call_insns
= NULL_RTX
;
1845 /* Sequence of insns to perform a tail "call". */
1846 rtx tail_call_insns
= NULL_RTX
;
1847 /* Data type of the function. */
1849 tree type_arg_types
;
1850 /* Declaration of the function being called,
1851 or 0 if the function is computed (not known by name). */
1853 /* The type of the function being called. */
1855 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
1858 /* Register in which non-BLKmode value will be returned,
1859 or 0 if no value or if value is BLKmode. */
1861 /* Address where we should return a BLKmode value;
1862 0 if value not BLKmode. */
1863 rtx structure_value_addr
= 0;
1864 /* Nonzero if that address is being passed by treating it as
1865 an extra, implicit first parameter. Otherwise,
1866 it is passed by being copied directly into struct_value_rtx. */
1867 int structure_value_addr_parm
= 0;
1868 /* Size of aggregate value wanted, or zero if none wanted
1869 or if we are using the non-reentrant PCC calling convention
1870 or expecting the value in registers. */
1871 HOST_WIDE_INT struct_value_size
= 0;
1872 /* Nonzero if called function returns an aggregate in memory PCC style,
1873 by returning the address of where to find it. */
1874 int pcc_struct_value
= 0;
1875 rtx struct_value
= 0;
1877 /* Number of actual parameters in this call, including struct value addr. */
1879 /* Number of named args. Args after this are anonymous ones
1880 and they must all go on the stack. */
1883 /* Vector of information about each argument.
1884 Arguments are numbered in the order they will be pushed,
1885 not the order they are written. */
1886 struct arg_data
*args
;
1888 /* Total size in bytes of all the stack-parms scanned so far. */
1889 struct args_size args_size
;
1890 struct args_size adjusted_args_size
;
1891 /* Size of arguments before any adjustments (such as rounding). */
1892 int unadjusted_args_size
;
1893 /* Data on reg parms scanned so far. */
1894 CUMULATIVE_ARGS args_so_far
;
1895 /* Nonzero if a reg parm has been scanned. */
1897 /* Nonzero if this is an indirect function call. */
1899 /* Nonzero if we must avoid push-insns in the args for this call.
1900 If stack space is allocated for register parameters, but not by the
1901 caller, then it is preallocated in the fixed part of the stack frame.
1902 So the entire argument block must then be preallocated (i.e., we
1903 ignore PUSH_ROUNDING in that case). */
1905 int must_preallocate
= !PUSH_ARGS
;
1907 /* Size of the stack reserved for parameter registers. */
1908 int reg_parm_stack_space
= 0;
1910 /* Address of space preallocated for stack parms
1911 (on machines that lack push insns), or 0 if space not preallocated. */
1914 /* Mask of ECF_ flags. */
1916 #ifdef REG_PARM_STACK_SPACE
1917 /* Define the boundary of the register parm stack space that needs to be
1919 int low_to_save
, high_to_save
;
1920 rtx save_area
= 0; /* Place that it is saved */
1923 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
1924 char *initial_stack_usage_map
= stack_usage_map
;
1926 int old_stack_allocated
;
1928 /* State variables to track stack modifications. */
1929 rtx old_stack_level
= 0;
1930 int old_stack_arg_under_construction
= 0;
1931 int old_pending_adj
= 0;
1932 int old_inhibit_defer_pop
= inhibit_defer_pop
;
1934 /* Some stack pointer alterations we make are performed via
1935 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
1936 which we then also need to save/restore along the way. */
1937 int old_stack_pointer_delta
= 0;
1940 tree p
= TREE_OPERAND (exp
, 0);
1941 tree addr
= TREE_OPERAND (exp
, 0);
1943 /* The alignment of the stack, in bits. */
1944 unsigned HOST_WIDE_INT preferred_stack_boundary
;
1945 /* The alignment of the stack, in bytes. */
1946 unsigned HOST_WIDE_INT preferred_unit_stack_boundary
;
1947 /* The static chain value to use for this call. */
1948 rtx static_chain_value
;
1949 /* See if this is "nothrow" function call. */
1950 if (TREE_NOTHROW (exp
))
1951 flags
|= ECF_NOTHROW
;
1953 /* See if we can find a DECL-node for the actual function, and get the
1954 function attributes (flags) from the function decl or type node. */
1955 fndecl
= get_callee_fndecl (exp
);
1958 fntype
= TREE_TYPE (fndecl
);
1959 flags
|= flags_from_decl_or_type (fndecl
);
1963 fntype
= TREE_TYPE (TREE_TYPE (p
));
1964 flags
|= flags_from_decl_or_type (fntype
);
1967 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
1969 /* Warn if this value is an aggregate type,
1970 regardless of which calling convention we are using for it. */
1971 if (warn_aggregate_return
&& AGGREGATE_TYPE_P (TREE_TYPE (exp
)))
1972 warning ("function call has aggregate value");
1974 /* If the result of a pure or const function call is ignored (or void),
1975 and none of its arguments are volatile, we can avoid expanding the
1976 call and just evaluate the arguments for side-effects. */
1977 if ((flags
& (ECF_CONST
| ECF_PURE
))
1978 && (ignore
|| target
== const0_rtx
1979 || TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
))
1981 bool volatilep
= false;
1984 for (arg
= actparms
; arg
; arg
= TREE_CHAIN (arg
))
1985 if (TREE_THIS_VOLATILE (TREE_VALUE (arg
)))
1993 for (arg
= actparms
; arg
; arg
= TREE_CHAIN (arg
))
1994 expand_expr (TREE_VALUE (arg
), const0_rtx
,
1995 VOIDmode
, EXPAND_NORMAL
);
2000 #ifdef REG_PARM_STACK_SPACE
2001 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
2004 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2005 if (reg_parm_stack_space
> 0 && PUSH_ARGS
)
2006 must_preallocate
= 1;
2009 /* Set up a place to return a structure. */
2011 /* Cater to broken compilers. */
2012 if (aggregate_value_p (exp
, fndecl
))
2014 /* This call returns a big structure. */
2015 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
2017 #ifdef PCC_STATIC_STRUCT_RETURN
2019 pcc_struct_value
= 1;
2021 #else /* not PCC_STATIC_STRUCT_RETURN */
2023 struct_value_size
= int_size_in_bytes (TREE_TYPE (exp
));
2025 if (CALL_EXPR_HAS_RETURN_SLOT_ADDR (exp
))
2027 /* The structure value address arg is already in actparms.
2028 Pull it out. It might be nice to just leave it there, but
2029 we need to set structure_value_addr. */
2030 tree return_arg
= TREE_VALUE (actparms
);
2031 actparms
= TREE_CHAIN (actparms
);
2032 structure_value_addr
= expand_expr (return_arg
, NULL_RTX
,
2033 VOIDmode
, EXPAND_NORMAL
);
2035 else if (target
&& MEM_P (target
))
2036 structure_value_addr
= XEXP (target
, 0);
2039 /* For variable-sized objects, we must be called with a target
2040 specified. If we were to allocate space on the stack here,
2041 we would have no way of knowing when to free it. */
2042 rtx d
= assign_temp (TREE_TYPE (exp
), 1, 1, 1);
2044 mark_temp_addr_taken (d
);
2045 structure_value_addr
= XEXP (d
, 0);
2049 #endif /* not PCC_STATIC_STRUCT_RETURN */
2052 /* Figure out the amount to which the stack should be aligned. */
2053 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2056 struct cgraph_rtl_info
*i
= cgraph_rtl_info (fndecl
);
2057 if (i
&& i
->preferred_incoming_stack_boundary
)
2058 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
2061 /* Operand 0 is a pointer-to-function; get the type of the function. */
2062 funtype
= TREE_TYPE (addr
);
2063 if (! POINTER_TYPE_P (funtype
))
2065 funtype
= TREE_TYPE (funtype
);
2067 /* Munge the tree to split complex arguments into their imaginary
2069 if (targetm
.calls
.split_complex_arg
)
2071 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
2072 actparms
= split_complex_values (actparms
);
2075 type_arg_types
= TYPE_ARG_TYPES (funtype
);
2077 if (flags
& ECF_MAY_BE_ALLOCA
)
2078 current_function_calls_alloca
= 1;
2080 /* If struct_value_rtx is 0, it means pass the address
2081 as if it were an extra parameter. */
2082 if (structure_value_addr
&& struct_value
== 0)
2084 /* If structure_value_addr is a REG other than
2085 virtual_outgoing_args_rtx, we can use always use it. If it
2086 is not a REG, we must always copy it into a register.
2087 If it is virtual_outgoing_args_rtx, we must copy it to another
2088 register in some cases. */
2089 rtx temp
= (!REG_P (structure_value_addr
)
2090 || (ACCUMULATE_OUTGOING_ARGS
2091 && stack_arg_under_construction
2092 && structure_value_addr
== virtual_outgoing_args_rtx
)
2093 ? copy_addr_to_reg (convert_memory_address
2094 (Pmode
, structure_value_addr
))
2095 : structure_value_addr
);
2098 = tree_cons (error_mark_node
,
2099 make_tree (build_pointer_type (TREE_TYPE (funtype
)),
2102 structure_value_addr_parm
= 1;
2105 /* Count the arguments and set NUM_ACTUALS. */
2106 for (p
= actparms
, num_actuals
= 0; p
; p
= TREE_CHAIN (p
))
2109 /* Compute number of named args.
2110 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2112 if (type_arg_types
!= 0)
2114 = (list_length (type_arg_types
)
2115 /* Count the struct value address, if it is passed as a parm. */
2116 + structure_value_addr_parm
);
2118 /* If we know nothing, treat all args as named. */
2119 n_named_args
= num_actuals
;
2121 /* Start updating where the next arg would go.
2123 On some machines (such as the PA) indirect calls have a different
2124 calling convention than normal calls. The fourth argument in
2125 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2127 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
2129 /* Now possibly adjust the number of named args.
2130 Normally, don't include the last named arg if anonymous args follow.
2131 We do include the last named arg if
2132 targetm.calls.strict_argument_naming() returns nonzero.
2133 (If no anonymous args follow, the result of list_length is actually
2134 one too large. This is harmless.)
2136 If targetm.calls.pretend_outgoing_varargs_named() returns
2137 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2138 this machine will be able to place unnamed args that were passed
2139 in registers into the stack. So treat all args as named. This
2140 allows the insns emitting for a specific argument list to be
2141 independent of the function declaration.
2143 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2144 we do not have any reliable way to pass unnamed args in
2145 registers, so we must force them into memory. */
2147 if (type_arg_types
!= 0
2148 && targetm
.calls
.strict_argument_naming (&args_so_far
))
2150 else if (type_arg_types
!= 0
2151 && ! targetm
.calls
.pretend_outgoing_varargs_named (&args_so_far
))
2152 /* Don't include the last named arg. */
2155 /* Treat all args as named. */
2156 n_named_args
= num_actuals
;
2158 /* Make a vector to hold all the information about each arg. */
2159 args
= alloca (num_actuals
* sizeof (struct arg_data
));
2160 memset (args
, 0, num_actuals
* sizeof (struct arg_data
));
2162 /* Build up entries in the ARGS array, compute the size of the
2163 arguments into ARGS_SIZE, etc. */
2164 initialize_argument_information (num_actuals
, args
, &args_size
,
2165 n_named_args
, actparms
, fndecl
,
2166 &args_so_far
, reg_parm_stack_space
,
2167 &old_stack_level
, &old_pending_adj
,
2168 &must_preallocate
, &flags
,
2169 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
2173 /* If this function requires a variable-sized argument list, don't
2174 try to make a cse'able block for this call. We may be able to
2175 do this eventually, but it is too complicated to keep track of
2176 what insns go in the cse'able block and which don't. */
2178 flags
&= ~ECF_LIBCALL_BLOCK
;
2179 must_preallocate
= 1;
2182 /* Now make final decision about preallocating stack space. */
2183 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2187 /* If the structure value address will reference the stack pointer, we
2188 must stabilize it. We don't need to do this if we know that we are
2189 not going to adjust the stack pointer in processing this call. */
2191 if (structure_value_addr
2192 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2193 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2194 structure_value_addr
))
2196 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2197 structure_value_addr
= copy_to_reg (structure_value_addr
);
2199 /* Tail calls can make things harder to debug, and we've traditionally
2200 pushed these optimizations into -O2. Don't try if we're already
2201 expanding a call, as that means we're an argument. Don't try if
2202 there's cleanups, as we know there's code to follow the call. */
2204 if (currently_expanding_call
++ != 0
2205 || !flag_optimize_sibling_calls
2207 || lookup_stmt_eh_region (exp
) >= 0)
2210 /* Rest of purposes for tail call optimizations to fail. */
2212 #ifdef HAVE_sibcall_epilogue
2213 !HAVE_sibcall_epilogue
2218 /* Doing sibling call optimization needs some work, since
2219 structure_value_addr can be allocated on the stack.
2220 It does not seem worth the effort since few optimizable
2221 sibling calls will return a structure. */
2222 || structure_value_addr
!= NULL_RTX
2223 /* Check whether the target is able to optimize the call
2225 || !targetm
.function_ok_for_sibcall (fndecl
, exp
)
2226 /* Functions that do not return exactly once may not be sibcall
2228 || (flags
& (ECF_RETURNS_TWICE
| ECF_LONGJMP
| ECF_NORETURN
))
2229 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
)))
2230 /* If the called function is nested in the current one, it might access
2231 some of the caller's arguments, but could clobber them beforehand if
2232 the argument areas are shared. */
2233 || (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
2234 /* If this function requires more stack slots than the current
2235 function, we cannot change it into a sibling call. */
2236 || args_size
.constant
> current_function_args_size
2237 /* If the callee pops its own arguments, then it must pop exactly
2238 the same number of arguments as the current function. */
2239 || (RETURN_POPS_ARGS (fndecl
, funtype
, args_size
.constant
)
2240 != RETURN_POPS_ARGS (current_function_decl
,
2241 TREE_TYPE (current_function_decl
),
2242 current_function_args_size
))
2243 || !lang_hooks
.decls
.ok_for_sibcall (fndecl
))
2246 /* Ensure current function's preferred stack boundary is at least
2247 what we need. We don't have to increase alignment for recursive
2249 if (cfun
->preferred_stack_boundary
< preferred_stack_boundary
2250 && fndecl
!= current_function_decl
)
2251 cfun
->preferred_stack_boundary
= preferred_stack_boundary
;
2252 if (fndecl
== current_function_decl
)
2253 cfun
->recursive_call_emit
= true;
2255 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2257 /* We want to make two insn chains; one for a sibling call, the other
2258 for a normal call. We will select one of the two chains after
2259 initial RTL generation is complete. */
2260 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
2262 int sibcall_failure
= 0;
2263 /* We want to emit any pending stack adjustments before the tail
2264 recursion "call". That way we know any adjustment after the tail
2265 recursion call can be ignored if we indeed use the tail
2267 int save_pending_stack_adjust
= 0;
2268 int save_stack_pointer_delta
= 0;
2270 rtx before_call
, next_arg_reg
;
2274 /* State variables we need to save and restore between
2276 save_pending_stack_adjust
= pending_stack_adjust
;
2277 save_stack_pointer_delta
= stack_pointer_delta
;
2280 flags
&= ~ECF_SIBCALL
;
2282 flags
|= ECF_SIBCALL
;
2284 /* Other state variables that we must reinitialize each time
2285 through the loop (that are not initialized by the loop itself). */
2289 /* Start a new sequence for the normal call case.
2291 From this point on, if the sibling call fails, we want to set
2292 sibcall_failure instead of continuing the loop. */
2295 /* Don't let pending stack adjusts add up to too much.
2296 Also, do all pending adjustments now if there is any chance
2297 this might be a call to alloca or if we are expanding a sibling
2298 call sequence or if we are calling a function that is to return
2299 with stack pointer depressed. */
2300 if (pending_stack_adjust
>= 32
2301 || (pending_stack_adjust
> 0
2302 && (flags
& (ECF_MAY_BE_ALLOCA
| ECF_SP_DEPRESSED
)))
2304 do_pending_stack_adjust ();
2306 /* When calling a const function, we must pop the stack args right away,
2307 so that the pop is deleted or moved with the call. */
2308 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
2311 /* Precompute any arguments as needed. */
2313 precompute_arguments (flags
, num_actuals
, args
);
2315 /* Now we are about to start emitting insns that can be deleted
2316 if a libcall is deleted. */
2317 if (pass
&& (flags
& (ECF_LIBCALL_BLOCK
| ECF_MALLOC
)))
2320 adjusted_args_size
= args_size
;
2321 /* Compute the actual size of the argument block required. The variable
2322 and constant sizes must be combined, the size may have to be rounded,
2323 and there may be a minimum required size. When generating a sibcall
2324 pattern, do not round up, since we'll be re-using whatever space our
2326 unadjusted_args_size
2327 = compute_argument_block_size (reg_parm_stack_space
,
2328 &adjusted_args_size
,
2330 : preferred_stack_boundary
));
2332 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2334 /* The argument block when performing a sibling call is the
2335 incoming argument block. */
2338 argblock
= virtual_incoming_args_rtx
;
2340 #ifdef STACK_GROWS_DOWNWARD
2341 = plus_constant (argblock
, current_function_pretend_args_size
);
2343 = plus_constant (argblock
, -current_function_pretend_args_size
);
2345 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2346 sbitmap_zero (stored_args_map
);
2349 /* If we have no actual push instructions, or shouldn't use them,
2350 make space for all args right now. */
2351 else if (adjusted_args_size
.var
!= 0)
2353 if (old_stack_level
== 0)
2355 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
2356 old_stack_pointer_delta
= stack_pointer_delta
;
2357 old_pending_adj
= pending_stack_adjust
;
2358 pending_stack_adjust
= 0;
2359 /* stack_arg_under_construction says whether a stack arg is
2360 being constructed at the old stack level. Pushing the stack
2361 gets a clean outgoing argument block. */
2362 old_stack_arg_under_construction
= stack_arg_under_construction
;
2363 stack_arg_under_construction
= 0;
2365 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2369 /* Note that we must go through the motions of allocating an argument
2370 block even if the size is zero because we may be storing args
2371 in the area reserved for register arguments, which may be part of
2374 int needed
= adjusted_args_size
.constant
;
2376 /* Store the maximum argument space used. It will be pushed by
2377 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2380 if (needed
> current_function_outgoing_args_size
)
2381 current_function_outgoing_args_size
= needed
;
2383 if (must_preallocate
)
2385 if (ACCUMULATE_OUTGOING_ARGS
)
2387 /* Since the stack pointer will never be pushed, it is
2388 possible for the evaluation of a parm to clobber
2389 something we have already written to the stack.
2390 Since most function calls on RISC machines do not use
2391 the stack, this is uncommon, but must work correctly.
2393 Therefore, we save any area of the stack that was already
2394 written and that we are using. Here we set up to do this
2395 by making a new stack usage map from the old one. The
2396 actual save will be done by store_one_arg.
2398 Another approach might be to try to reorder the argument
2399 evaluations to avoid this conflicting stack usage. */
2401 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2402 /* Since we will be writing into the entire argument area,
2403 the map must be allocated for its entire size, not just
2404 the part that is the responsibility of the caller. */
2405 needed
+= reg_parm_stack_space
;
2408 #ifdef ARGS_GROW_DOWNWARD
2409 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2412 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2415 stack_usage_map
= alloca (highest_outgoing_arg_in_use
);
2417 if (initial_highest_arg_in_use
)
2418 memcpy (stack_usage_map
, initial_stack_usage_map
,
2419 initial_highest_arg_in_use
);
2421 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2422 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2423 (highest_outgoing_arg_in_use
2424 - initial_highest_arg_in_use
));
2427 /* The address of the outgoing argument list must not be
2428 copied to a register here, because argblock would be left
2429 pointing to the wrong place after the call to
2430 allocate_dynamic_stack_space below. */
2432 argblock
= virtual_outgoing_args_rtx
;
2436 if (inhibit_defer_pop
== 0)
2438 /* Try to reuse some or all of the pending_stack_adjust
2439 to get this space. */
2441 = (combine_pending_stack_adjustment_and_call
2442 (unadjusted_args_size
,
2443 &adjusted_args_size
,
2444 preferred_unit_stack_boundary
));
2446 /* combine_pending_stack_adjustment_and_call computes
2447 an adjustment before the arguments are allocated.
2448 Account for them and see whether or not the stack
2449 needs to go up or down. */
2450 needed
= unadjusted_args_size
- needed
;
2454 /* We're releasing stack space. */
2455 /* ??? We can avoid any adjustment at all if we're
2456 already aligned. FIXME. */
2457 pending_stack_adjust
= -needed
;
2458 do_pending_stack_adjust ();
2462 /* We need to allocate space. We'll do that in
2463 push_block below. */
2464 pending_stack_adjust
= 0;
2467 /* Special case this because overhead of `push_block' in
2468 this case is non-trivial. */
2470 argblock
= virtual_outgoing_args_rtx
;
2473 argblock
= push_block (GEN_INT (needed
), 0, 0);
2474 #ifdef ARGS_GROW_DOWNWARD
2475 argblock
= plus_constant (argblock
, needed
);
2479 /* We only really need to call `copy_to_reg' in the case
2480 where push insns are going to be used to pass ARGBLOCK
2481 to a function call in ARGS. In that case, the stack
2482 pointer changes value from the allocation point to the
2483 call point, and hence the value of
2484 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2485 as well always do it. */
2486 argblock
= copy_to_reg (argblock
);
2491 if (ACCUMULATE_OUTGOING_ARGS
)
2493 /* The save/restore code in store_one_arg handles all
2494 cases except one: a constructor call (including a C
2495 function returning a BLKmode struct) to initialize
2497 if (stack_arg_under_construction
)
2499 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2500 rtx push_size
= GEN_INT (reg_parm_stack_space
2501 + adjusted_args_size
.constant
);
2503 rtx push_size
= GEN_INT (adjusted_args_size
.constant
);
2505 if (old_stack_level
== 0)
2507 emit_stack_save (SAVE_BLOCK
, &old_stack_level
,
2509 old_stack_pointer_delta
= stack_pointer_delta
;
2510 old_pending_adj
= pending_stack_adjust
;
2511 pending_stack_adjust
= 0;
2512 /* stack_arg_under_construction says whether a stack
2513 arg is being constructed at the old stack level.
2514 Pushing the stack gets a clean outgoing argument
2516 old_stack_arg_under_construction
2517 = stack_arg_under_construction
;
2518 stack_arg_under_construction
= 0;
2519 /* Make a new map for the new argument list. */
2520 stack_usage_map
= alloca (highest_outgoing_arg_in_use
);
2521 memset (stack_usage_map
, 0, highest_outgoing_arg_in_use
);
2522 highest_outgoing_arg_in_use
= 0;
2524 allocate_dynamic_stack_space (push_size
, NULL_RTX
,
2528 /* If argument evaluation might modify the stack pointer,
2529 copy the address of the argument list to a register. */
2530 for (i
= 0; i
< num_actuals
; i
++)
2531 if (args
[i
].pass_on_stack
)
2533 argblock
= copy_addr_to_reg (argblock
);
2538 compute_argument_addresses (args
, argblock
, num_actuals
);
2540 /* If we push args individually in reverse order, perform stack alignment
2541 before the first push (the last arg). */
2542 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2543 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2545 /* When the stack adjustment is pending, we get better code
2546 by combining the adjustments. */
2547 if (pending_stack_adjust
2548 && ! (flags
& ECF_LIBCALL_BLOCK
)
2549 && ! inhibit_defer_pop
)
2551 pending_stack_adjust
2552 = (combine_pending_stack_adjustment_and_call
2553 (unadjusted_args_size
,
2554 &adjusted_args_size
,
2555 preferred_unit_stack_boundary
));
2556 do_pending_stack_adjust ();
2558 else if (argblock
== 0)
2559 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2560 - unadjusted_args_size
));
2562 /* Now that the stack is properly aligned, pops can't safely
2563 be deferred during the evaluation of the arguments. */
2566 funexp
= rtx_for_function_call (fndecl
, addr
);
2568 /* Figure out the register where the value, if any, will come back. */
2570 if (TYPE_MODE (TREE_TYPE (exp
)) != VOIDmode
2571 && ! structure_value_addr
)
2573 if (pcc_struct_value
)
2574 valreg
= hard_function_value (build_pointer_type (TREE_TYPE (exp
)),
2575 fndecl
, (pass
== 0));
2577 valreg
= hard_function_value (TREE_TYPE (exp
), fndecl
, (pass
== 0));
2580 /* Precompute all register parameters. It isn't safe to compute anything
2581 once we have started filling any specific hard regs. */
2582 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2584 if (TREE_OPERAND (exp
, 2))
2585 static_chain_value
= expand_expr (TREE_OPERAND (exp
, 2),
2586 NULL_RTX
, VOIDmode
, 0);
2588 static_chain_value
= 0;
2590 #ifdef REG_PARM_STACK_SPACE
2591 /* Save the fixed argument area if it's part of the caller's frame and
2592 is clobbered by argument setup for this call. */
2593 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2594 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2595 &low_to_save
, &high_to_save
);
2598 /* Now store (and compute if necessary) all non-register parms.
2599 These come before register parms, since they can require block-moves,
2600 which could clobber the registers used for register parms.
2601 Parms which have partial registers are not stored here,
2602 but we do preallocate space here if they want that. */
2604 for (i
= 0; i
< num_actuals
; i
++)
2605 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2607 rtx before_arg
= get_last_insn ();
2609 if (store_one_arg (&args
[i
], argblock
, flags
,
2610 adjusted_args_size
.var
!= 0,
2611 reg_parm_stack_space
)
2613 && check_sibcall_argument_overlap (before_arg
,
2615 sibcall_failure
= 1;
2617 if (flags
& ECF_CONST
2619 && args
[i
].value
== args
[i
].stack
)
2620 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
2621 gen_rtx_USE (VOIDmode
,
2626 /* If we have a parm that is passed in registers but not in memory
2627 and whose alignment does not permit a direct copy into registers,
2628 make a group of pseudos that correspond to each register that we
2630 if (STRICT_ALIGNMENT
)
2631 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2633 /* Now store any partially-in-registers parm.
2634 This is the last place a block-move can happen. */
2636 for (i
= 0; i
< num_actuals
; i
++)
2637 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2639 rtx before_arg
= get_last_insn ();
2641 if (store_one_arg (&args
[i
], argblock
, flags
,
2642 adjusted_args_size
.var
!= 0,
2643 reg_parm_stack_space
)
2645 && check_sibcall_argument_overlap (before_arg
,
2647 sibcall_failure
= 1;
2650 /* If we pushed args in forward order, perform stack alignment
2651 after pushing the last arg. */
2652 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
2653 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2654 - unadjusted_args_size
));
2656 /* If register arguments require space on the stack and stack space
2657 was not preallocated, allocate stack space here for arguments
2658 passed in registers. */
2659 #ifdef OUTGOING_REG_PARM_STACK_SPACE
2660 if (!ACCUMULATE_OUTGOING_ARGS
2661 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
2662 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
2665 /* Pass the function the address in which to return a
2667 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
2669 structure_value_addr
2670 = convert_memory_address (Pmode
, structure_value_addr
);
2671 emit_move_insn (struct_value
,
2673 force_operand (structure_value_addr
,
2676 if (REG_P (struct_value
))
2677 use_reg (&call_fusage
, struct_value
);
2680 funexp
= prepare_call_address (funexp
, static_chain_value
,
2681 &call_fusage
, reg_parm_seen
, pass
== 0);
2683 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
2684 pass
== 0, &sibcall_failure
);
2686 /* Save a pointer to the last insn before the call, so that we can
2687 later safely search backwards to find the CALL_INSN. */
2688 before_call
= get_last_insn ();
2690 /* Set up next argument register. For sibling calls on machines
2691 with register windows this should be the incoming register. */
2692 #ifdef FUNCTION_INCOMING_ARG
2694 next_arg_reg
= FUNCTION_INCOMING_ARG (args_so_far
, VOIDmode
,
2698 next_arg_reg
= FUNCTION_ARG (args_so_far
, VOIDmode
,
2701 /* All arguments and registers used for the call must be set up by
2704 /* Stack must be properly aligned now. */
2705 if (pass
&& stack_pointer_delta
% preferred_unit_stack_boundary
)
2708 /* Generate the actual call instruction. */
2709 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
2710 adjusted_args_size
.constant
, struct_value_size
,
2711 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
2712 flags
, & args_so_far
);
2714 /* If call is cse'able, make appropriate pair of reg-notes around it.
2715 Test valreg so we don't crash; may safely ignore `const'
2716 if return type is void. Disable for PARALLEL return values, because
2717 we have no way to move such values into a pseudo register. */
2718 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
2722 bool failed
= valreg
== 0 || GET_CODE (valreg
) == PARALLEL
;
2724 insns
= get_insns ();
2726 /* Expansion of block moves possibly introduced a loop that may
2727 not appear inside libcall block. */
2728 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
2740 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2742 /* Mark the return value as a pointer if needed. */
2743 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
2744 mark_reg_pointer (temp
,
2745 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp
))));
2748 if (flag_unsafe_math_optimizations
2750 && DECL_BUILT_IN (fndecl
)
2751 && (DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRT
2752 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRTF
2753 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRTL
))
2754 note
= gen_rtx_fmt_e (SQRT
,
2756 args
[0].initial_value
);
2759 /* Construct an "equal form" for the value which
2760 mentions all the arguments in order as well as
2761 the function name. */
2762 for (i
= 0; i
< num_actuals
; i
++)
2763 note
= gen_rtx_EXPR_LIST (VOIDmode
,
2764 args
[i
].initial_value
, note
);
2765 note
= gen_rtx_EXPR_LIST (VOIDmode
, funexp
, note
);
2767 if (flags
& ECF_PURE
)
2768 note
= gen_rtx_EXPR_LIST (VOIDmode
,
2769 gen_rtx_USE (VOIDmode
,
2770 gen_rtx_MEM (BLKmode
,
2771 gen_rtx_SCRATCH (VOIDmode
))),
2774 emit_libcall_block (insns
, temp
, valreg
, note
);
2779 else if (pass
&& (flags
& ECF_MALLOC
))
2781 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2784 /* The return value from a malloc-like function is a pointer. */
2785 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
2786 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
2788 emit_move_insn (temp
, valreg
);
2790 /* The return value from a malloc-like function can not alias
2792 last
= get_last_insn ();
2794 gen_rtx_EXPR_LIST (REG_NOALIAS
, temp
, REG_NOTES (last
));
2796 /* Write out the sequence. */
2797 insns
= get_insns ();
2803 /* For calls to `setjmp', etc., inform flow.c it should complain
2804 if nonvolatile values are live. For functions that cannot return,
2805 inform flow that control does not fall through. */
2807 if ((flags
& (ECF_NORETURN
| ECF_LONGJMP
)) || pass
== 0)
2809 /* The barrier must be emitted
2810 immediately after the CALL_INSN. Some ports emit more
2811 than just a CALL_INSN above, so we must search for it here. */
2813 rtx last
= get_last_insn ();
2814 while (!CALL_P (last
))
2816 last
= PREV_INSN (last
);
2817 /* There was no CALL_INSN? */
2818 if (last
== before_call
)
2822 emit_barrier_after (last
);
2824 /* Stack adjustments after a noreturn call are dead code.
2825 However when NO_DEFER_POP is in effect, we must preserve
2826 stack_pointer_delta. */
2827 if (inhibit_defer_pop
== 0)
2829 stack_pointer_delta
= old_stack_allocated
;
2830 pending_stack_adjust
= 0;
2834 if (flags
& ECF_LONGJMP
)
2835 current_function_calls_longjmp
= 1;
2837 /* If value type not void, return an rtx for the value. */
2839 if (TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
2841 target
= const0_rtx
;
2842 else if (structure_value_addr
)
2844 if (target
== 0 || !MEM_P (target
))
2847 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
2848 memory_address (TYPE_MODE (TREE_TYPE (exp
)),
2849 structure_value_addr
));
2850 set_mem_attributes (target
, exp
, 1);
2853 else if (pcc_struct_value
)
2855 /* This is the special C++ case where we need to
2856 know what the true target was. We take care to
2857 never use this value more than once in one expression. */
2858 target
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
2859 copy_to_reg (valreg
));
2860 set_mem_attributes (target
, exp
, 1);
2862 /* Handle calls that return values in multiple non-contiguous locations.
2863 The Irix 6 ABI has examples of this. */
2864 else if (GET_CODE (valreg
) == PARALLEL
)
2868 /* This will only be assigned once, so it can be readonly. */
2869 tree nt
= build_qualified_type (TREE_TYPE (exp
),
2870 (TYPE_QUALS (TREE_TYPE (exp
))
2871 | TYPE_QUAL_CONST
));
2873 target
= assign_temp (nt
, 0, 1, 1);
2874 preserve_temp_slots (target
);
2877 if (! rtx_equal_p (target
, valreg
))
2878 emit_group_store (target
, valreg
, TREE_TYPE (exp
),
2879 int_size_in_bytes (TREE_TYPE (exp
)));
2881 /* We can not support sibling calls for this case. */
2882 sibcall_failure
= 1;
2885 && GET_MODE (target
) == TYPE_MODE (TREE_TYPE (exp
))
2886 && GET_MODE (target
) == GET_MODE (valreg
))
2888 /* TARGET and VALREG cannot be equal at this point because the
2889 latter would not have REG_FUNCTION_VALUE_P true, while the
2890 former would if it were referring to the same register.
2892 If they refer to the same register, this move will be a no-op,
2893 except when function inlining is being done. */
2894 emit_move_insn (target
, valreg
);
2896 /* If we are setting a MEM, this code must be executed. Since it is
2897 emitted after the call insn, sibcall optimization cannot be
2898 performed in that case. */
2900 sibcall_failure
= 1;
2902 else if (TYPE_MODE (TREE_TYPE (exp
)) == BLKmode
)
2904 target
= copy_blkmode_from_reg (target
, valreg
, TREE_TYPE (exp
));
2906 /* We can not support sibling calls for this case. */
2907 sibcall_failure
= 1;
2911 if (shift_returned_value (TREE_TYPE (exp
), &valreg
))
2912 sibcall_failure
= 1;
2914 target
= copy_to_reg (valreg
);
2917 if (targetm
.calls
.promote_function_return(funtype
))
2919 /* If we promoted this return value, make the proper SUBREG. TARGET
2920 might be const0_rtx here, so be careful. */
2922 && TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
2923 && GET_MODE (target
) != TYPE_MODE (TREE_TYPE (exp
)))
2925 tree type
= TREE_TYPE (exp
);
2926 int unsignedp
= TYPE_UNSIGNED (type
);
2929 /* If we don't promote as expected, something is wrong. */
2930 if (GET_MODE (target
)
2931 != promote_mode (type
, TYPE_MODE (type
), &unsignedp
, 1))
2934 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
2935 && GET_MODE_SIZE (GET_MODE (target
))
2936 > GET_MODE_SIZE (TYPE_MODE (type
)))
2938 offset
= GET_MODE_SIZE (GET_MODE (target
))
2939 - GET_MODE_SIZE (TYPE_MODE (type
));
2940 if (! BYTES_BIG_ENDIAN
)
2941 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
2942 else if (! WORDS_BIG_ENDIAN
)
2943 offset
%= UNITS_PER_WORD
;
2945 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
2946 SUBREG_PROMOTED_VAR_P (target
) = 1;
2947 SUBREG_PROMOTED_UNSIGNED_SET (target
, unsignedp
);
2951 /* If size of args is variable or this was a constructor call for a stack
2952 argument, restore saved stack-pointer value. */
2954 if (old_stack_level
&& ! (flags
& ECF_SP_DEPRESSED
))
2956 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
2957 stack_pointer_delta
= old_stack_pointer_delta
;
2958 pending_stack_adjust
= old_pending_adj
;
2959 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2960 stack_arg_under_construction
= old_stack_arg_under_construction
;
2961 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
2962 stack_usage_map
= initial_stack_usage_map
;
2963 sibcall_failure
= 1;
2965 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2967 #ifdef REG_PARM_STACK_SPACE
2969 restore_fixed_argument_area (save_area
, argblock
,
2970 high_to_save
, low_to_save
);
2973 /* If we saved any argument areas, restore them. */
2974 for (i
= 0; i
< num_actuals
; i
++)
2975 if (args
[i
].save_area
)
2977 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
2979 = gen_rtx_MEM (save_mode
,
2980 memory_address (save_mode
,
2981 XEXP (args
[i
].stack_slot
, 0)));
2983 if (save_mode
!= BLKmode
)
2984 emit_move_insn (stack_area
, args
[i
].save_area
);
2986 emit_block_move (stack_area
, args
[i
].save_area
,
2987 GEN_INT (args
[i
].locate
.size
.constant
),
2988 BLOCK_OP_CALL_PARM
);
2991 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
2992 stack_usage_map
= initial_stack_usage_map
;
2995 /* If this was alloca, record the new stack level for nonlocal gotos.
2996 Check for the handler slots since we might not have a save area
2997 for non-local gotos. */
2999 if ((flags
& ECF_MAY_BE_ALLOCA
) && cfun
->nonlocal_goto_save_area
!= 0)
3000 update_nonlocal_goto_save_area ();
3002 /* Free up storage we no longer need. */
3003 for (i
= 0; i
< num_actuals
; ++i
)
3004 if (args
[i
].aligned_regs
)
3005 free (args
[i
].aligned_regs
);
3007 /* If this function is returning into a memory location marked as
3008 readonly, it means it is initializing that location. We normally treat
3009 functions as not clobbering such locations, so we need to specify that
3010 this one does. We do this by adding the appropriate CLOBBER to the
3011 CALL_INSN function usage list. This cannot be done by emitting a
3012 standalone CLOBBER after the call because the latter would be ignored
3013 by at least the delay slot scheduling pass. We do this now instead of
3014 adding to call_fusage before the call to emit_call_1 because TARGET
3015 may be modified in the meantime. */
3016 if (structure_value_addr
!= 0 && target
!= 0
3017 && MEM_P (target
) && RTX_UNCHANGING_P (target
))
3018 add_function_usage_to
3020 gen_rtx_EXPR_LIST (VOIDmode
, gen_rtx_CLOBBER (VOIDmode
, target
),
3023 insns
= get_insns ();
3028 tail_call_insns
= insns
;
3030 /* Restore the pending stack adjustment now that we have
3031 finished generating the sibling call sequence. */
3033 pending_stack_adjust
= save_pending_stack_adjust
;
3034 stack_pointer_delta
= save_stack_pointer_delta
;
3036 /* Prepare arg structure for next iteration. */
3037 for (i
= 0; i
< num_actuals
; i
++)
3040 args
[i
].aligned_regs
= 0;
3044 sbitmap_free (stored_args_map
);
3048 normal_call_insns
= insns
;
3050 /* Verify that we've deallocated all the stack we used. */
3051 if (! (flags
& (ECF_NORETURN
| ECF_LONGJMP
))
3052 && old_stack_allocated
!= stack_pointer_delta
3053 - pending_stack_adjust
)
3057 /* If something prevents making this a sibling call,
3058 zero out the sequence. */
3059 if (sibcall_failure
)
3060 tail_call_insns
= NULL_RTX
;
3065 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3066 arguments too, as argument area is now clobbered by the call. */
3067 if (tail_call_insns
)
3069 emit_insn (tail_call_insns
);
3070 cfun
->tail_call_emit
= true;
3073 emit_insn (normal_call_insns
);
3075 currently_expanding_call
--;
3077 /* If this function returns with the stack pointer depressed, ensure
3078 this block saves and restores the stack pointer, show it was
3079 changed, and adjust for any outgoing arg space. */
3080 if (flags
& ECF_SP_DEPRESSED
)
3082 clear_pending_stack_adjust ();
3083 emit_insn (gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
));
3084 emit_move_insn (virtual_stack_dynamic_rtx
, stack_pointer_rtx
);
3090 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3091 this function's incoming arguments.
3093 At the start of RTL generation we know the only REG_EQUIV notes
3094 in the rtl chain are those for incoming arguments, so we can safely
3095 flush any REG_EQUIV note.
3097 This is (slight) overkill. We could keep track of the highest
3098 argument we clobber and be more selective in removing notes, but it
3099 does not seem to be worth the effort. */
3101 fixup_tail_calls (void)
3106 purge_reg_equiv_notes ();
3108 /* A sibling call sequence also may invalidate RTX_UNCHANGING_P
3109 flag of some incoming arguments MEM RTLs, because it can write into
3110 those slots. We clear all those bits now.
3112 This is (slight) overkill, we could keep track of which arguments
3113 we actually write into. */
3114 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
3117 purge_mem_unchanging_flag (PATTERN (insn
));
3120 /* Similarly, invalidate RTX_UNCHANGING_P for any incoming
3121 arguments passed in registers. */
3122 for (arg
= DECL_ARGUMENTS (current_function_decl
);
3124 arg
= TREE_CHAIN (arg
))
3126 if (REG_P (DECL_RTL (arg
)))
3127 RTX_UNCHANGING_P (DECL_RTL (arg
)) = false;
3131 /* Traverse an argument list in VALUES and expand all complex
3132 arguments into their components. */
3134 split_complex_values (tree values
)
3138 /* Before allocating memory, check for the common case of no complex. */
3139 for (p
= values
; p
; p
= TREE_CHAIN (p
))
3141 tree type
= TREE_TYPE (TREE_VALUE (p
));
3142 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
3143 && targetm
.calls
.split_complex_arg (type
))
3149 values
= copy_list (values
);
3151 for (p
= values
; p
; p
= TREE_CHAIN (p
))
3153 tree complex_value
= TREE_VALUE (p
);
3156 complex_type
= TREE_TYPE (complex_value
);
3160 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
3161 && targetm
.calls
.split_complex_arg (complex_type
))
3164 tree real
, imag
, next
;
3166 subtype
= TREE_TYPE (complex_type
);
3167 complex_value
= save_expr (complex_value
);
3168 real
= build1 (REALPART_EXPR
, subtype
, complex_value
);
3169 imag
= build1 (IMAGPART_EXPR
, subtype
, complex_value
);
3171 TREE_VALUE (p
) = real
;
3172 next
= TREE_CHAIN (p
);
3173 imag
= build_tree_list (NULL_TREE
, imag
);
3174 TREE_CHAIN (p
) = imag
;
3175 TREE_CHAIN (imag
) = next
;
3177 /* Skip the newly created node. */
3185 /* Traverse a list of TYPES and expand all complex types into their
3188 split_complex_types (tree types
)
3192 /* Before allocating memory, check for the common case of no complex. */
3193 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3195 tree type
= TREE_VALUE (p
);
3196 if (TREE_CODE (type
) == COMPLEX_TYPE
3197 && targetm
.calls
.split_complex_arg (type
))
3203 types
= copy_list (types
);
3205 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3207 tree complex_type
= TREE_VALUE (p
);
3209 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
3210 && targetm
.calls
.split_complex_arg (complex_type
))
3214 /* Rewrite complex type with component type. */
3215 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
3216 next
= TREE_CHAIN (p
);
3218 /* Add another component type for the imaginary part. */
3219 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
3220 TREE_CHAIN (p
) = imag
;
3221 TREE_CHAIN (imag
) = next
;
3223 /* Skip the newly created node. */
3231 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3232 The RETVAL parameter specifies whether return value needs to be saved, other
3233 parameters are documented in the emit_library_call function below. */
3236 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
3237 enum libcall_type fn_type
,
3238 enum machine_mode outmode
, int nargs
, va_list p
)
3240 /* Total size in bytes of all the stack-parms scanned so far. */
3241 struct args_size args_size
;
3242 /* Size of arguments before any adjustments (such as rounding). */
3243 struct args_size original_args_size
;
3249 CUMULATIVE_ARGS args_so_far
;
3253 enum machine_mode mode
;
3256 struct locate_and_pad_arg_data locate
;
3260 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3261 rtx call_fusage
= 0;
3264 int pcc_struct_value
= 0;
3265 int struct_value_size
= 0;
3267 int reg_parm_stack_space
= 0;
3270 tree tfom
; /* type_for_mode (outmode, 0) */
3272 #ifdef REG_PARM_STACK_SPACE
3273 /* Define the boundary of the register parm stack space that needs to be
3275 int low_to_save
, high_to_save
;
3276 rtx save_area
= 0; /* Place that it is saved. */
3279 /* Size of the stack reserved for parameter registers. */
3280 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3281 char *initial_stack_usage_map
= stack_usage_map
;
3283 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
3285 #ifdef REG_PARM_STACK_SPACE
3286 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3289 /* By default, library functions can not throw. */
3290 flags
= ECF_NOTHROW
;
3302 case LCT_CONST_MAKE_BLOCK
:
3303 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
3305 case LCT_PURE_MAKE_BLOCK
:
3306 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
3309 flags
|= ECF_NORETURN
;
3312 flags
= ECF_NORETURN
;
3314 case LCT_ALWAYS_RETURN
:
3315 flags
= ECF_ALWAYS_RETURN
;
3317 case LCT_RETURNS_TWICE
:
3318 flags
= ECF_RETURNS_TWICE
;
3323 /* Ensure current function's preferred stack boundary is at least
3325 if (cfun
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3326 cfun
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3328 /* If this kind of value comes back in memory,
3329 decide where in memory it should come back. */
3330 if (outmode
!= VOIDmode
)
3332 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
3333 if (aggregate_value_p (tfom
, 0))
3335 #ifdef PCC_STATIC_STRUCT_RETURN
3337 = hard_function_value (build_pointer_type (tfom
), 0, 0);
3338 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3339 pcc_struct_value
= 1;
3341 value
= gen_reg_rtx (outmode
);
3342 #else /* not PCC_STATIC_STRUCT_RETURN */
3343 struct_value_size
= GET_MODE_SIZE (outmode
);
3344 if (value
!= 0 && MEM_P (value
))
3347 mem_value
= assign_temp (tfom
, 0, 1, 1);
3349 /* This call returns a big structure. */
3350 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3354 tfom
= void_type_node
;
3356 /* ??? Unfinished: must pass the memory address as an argument. */
3358 /* Copy all the libcall-arguments out of the varargs data
3359 and into a vector ARGVEC.
3361 Compute how to pass each argument. We only support a very small subset
3362 of the full argument passing conventions to limit complexity here since
3363 library functions shouldn't have many args. */
3365 argvec
= alloca ((nargs
+ 1) * sizeof (struct arg
));
3366 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3368 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3369 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3371 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0, nargs
);
3374 args_size
.constant
= 0;
3379 /* Now we are about to start emitting insns that can be deleted
3380 if a libcall is deleted. */
3381 if (flags
& ECF_LIBCALL_BLOCK
)
3386 /* If there's a structure value address to be passed,
3387 either pass it in the special place, or pass it as an extra argument. */
3388 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
3390 rtx addr
= XEXP (mem_value
, 0);
3393 /* Make sure it is a reasonable operand for a move or push insn. */
3394 if (!REG_P (addr
) && !MEM_P (addr
)
3395 && ! (CONSTANT_P (addr
) && LEGITIMATE_CONSTANT_P (addr
)))
3396 addr
= force_operand (addr
, NULL_RTX
);
3398 argvec
[count
].value
= addr
;
3399 argvec
[count
].mode
= Pmode
;
3400 argvec
[count
].partial
= 0;
3402 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, Pmode
, NULL_TREE
, 1);
3403 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, Pmode
, NULL_TREE
, 1))
3406 locate_and_pad_parm (Pmode
, NULL_TREE
,
3407 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3410 argvec
[count
].reg
!= 0,
3412 0, NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3414 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3415 || reg_parm_stack_space
> 0)
3416 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3418 FUNCTION_ARG_ADVANCE (args_so_far
, Pmode
, (tree
) 0, 1);
3423 for (; count
< nargs
; count
++)
3425 rtx val
= va_arg (p
, rtx
);
3426 enum machine_mode mode
= va_arg (p
, enum machine_mode
);
3428 /* We cannot convert the arg value to the mode the library wants here;
3429 must do it earlier where we know the signedness of the arg. */
3431 || (GET_MODE (val
) != mode
&& GET_MODE (val
) != VOIDmode
))
3434 /* Make sure it is a reasonable operand for a move or push insn. */
3435 if (!REG_P (val
) && !MEM_P (val
)
3436 && ! (CONSTANT_P (val
) && LEGITIMATE_CONSTANT_P (val
)))
3437 val
= force_operand (val
, NULL_RTX
);
3439 if (pass_by_reference (&args_so_far
, mode
, NULL_TREE
, 1))
3442 int must_copy
= ! FUNCTION_ARG_CALLEE_COPIES (args_so_far
, mode
,
3445 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3446 functions, so we have to pretend this isn't such a function. */
3447 if (flags
& ECF_LIBCALL_BLOCK
)
3449 rtx insns
= get_insns ();
3453 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3455 /* If this was a CONST function, it is now PURE since
3456 it now reads memory. */
3457 if (flags
& ECF_CONST
)
3459 flags
&= ~ECF_CONST
;
3463 if (GET_MODE (val
) == MEM
&& ! must_copy
)
3467 slot
= assign_temp (lang_hooks
.types
.type_for_mode (mode
, 0),
3469 emit_move_insn (slot
, val
);
3473 tree type
= lang_hooks
.types
.type_for_mode (mode
, 0);
3476 = gen_rtx_MEM (mode
,
3477 expand_expr (build1 (ADDR_EXPR
,
3478 build_pointer_type (type
),
3479 make_tree (type
, val
)),
3480 NULL_RTX
, VOIDmode
, 0));
3483 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3484 gen_rtx_USE (VOIDmode
, slot
),
3487 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3488 gen_rtx_CLOBBER (VOIDmode
,
3493 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3496 argvec
[count
].value
= val
;
3497 argvec
[count
].mode
= mode
;
3499 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, mode
, NULL_TREE
, 1);
3501 argvec
[count
].partial
3502 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, mode
, NULL_TREE
, 1);
3504 locate_and_pad_parm (mode
, NULL_TREE
,
3505 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3508 argvec
[count
].reg
!= 0,
3510 argvec
[count
].partial
,
3511 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3513 if (argvec
[count
].locate
.size
.var
)
3516 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3517 || reg_parm_stack_space
> 0)
3518 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3520 FUNCTION_ARG_ADVANCE (args_so_far
, mode
, (tree
) 0, 1);
3523 /* If this machine requires an external definition for library
3524 functions, write one out. */
3525 assemble_external_libcall (fun
);
3527 original_args_size
= args_size
;
3528 args_size
.constant
= (((args_size
.constant
3529 + stack_pointer_delta
3533 - stack_pointer_delta
);
3535 args_size
.constant
= MAX (args_size
.constant
,
3536 reg_parm_stack_space
);
3538 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3539 args_size
.constant
-= reg_parm_stack_space
;
3542 if (args_size
.constant
> current_function_outgoing_args_size
)
3543 current_function_outgoing_args_size
= args_size
.constant
;
3545 if (ACCUMULATE_OUTGOING_ARGS
)
3547 /* Since the stack pointer will never be pushed, it is possible for
3548 the evaluation of a parm to clobber something we have already
3549 written to the stack. Since most function calls on RISC machines
3550 do not use the stack, this is uncommon, but must work correctly.
3552 Therefore, we save any area of the stack that was already written
3553 and that we are using. Here we set up to do this by making a new
3554 stack usage map from the old one.
3556 Another approach might be to try to reorder the argument
3557 evaluations to avoid this conflicting stack usage. */
3559 needed
= args_size
.constant
;
3561 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3562 /* Since we will be writing into the entire argument area, the
3563 map must be allocated for its entire size, not just the part that
3564 is the responsibility of the caller. */
3565 needed
+= reg_parm_stack_space
;
3568 #ifdef ARGS_GROW_DOWNWARD
3569 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3572 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3575 stack_usage_map
= alloca (highest_outgoing_arg_in_use
);
3577 if (initial_highest_arg_in_use
)
3578 memcpy (stack_usage_map
, initial_stack_usage_map
,
3579 initial_highest_arg_in_use
);
3581 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3582 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3583 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3586 /* We must be careful to use virtual regs before they're instantiated,
3587 and real regs afterwards. Loop optimization, for example, can create
3588 new libcalls after we've instantiated the virtual regs, and if we
3589 use virtuals anyway, they won't match the rtl patterns. */
3591 if (virtuals_instantiated
)
3592 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3594 argblock
= virtual_outgoing_args_rtx
;
3599 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3602 /* If we push args individually in reverse order, perform stack alignment
3603 before the first push (the last arg). */
3604 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3605 anti_adjust_stack (GEN_INT (args_size
.constant
3606 - original_args_size
.constant
));
3608 if (PUSH_ARGS_REVERSED
)
3619 #ifdef REG_PARM_STACK_SPACE
3620 if (ACCUMULATE_OUTGOING_ARGS
)
3622 /* The argument list is the property of the called routine and it
3623 may clobber it. If the fixed area has been used for previous
3624 parameters, we must save and restore it. */
3625 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
3626 &low_to_save
, &high_to_save
);
3630 /* Push the args that need to be pushed. */
3632 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3633 are to be pushed. */
3634 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3636 enum machine_mode mode
= argvec
[argnum
].mode
;
3637 rtx val
= argvec
[argnum
].value
;
3638 rtx reg
= argvec
[argnum
].reg
;
3639 int partial
= argvec
[argnum
].partial
;
3640 int lower_bound
= 0, upper_bound
= 0, i
;
3642 if (! (reg
!= 0 && partial
== 0))
3644 if (ACCUMULATE_OUTGOING_ARGS
)
3646 /* If this is being stored into a pre-allocated, fixed-size,
3647 stack area, save any previous data at that location. */
3649 #ifdef ARGS_GROW_DOWNWARD
3650 /* stack_slot is negative, but we want to index stack_usage_map
3651 with positive values. */
3652 upper_bound
= -argvec
[argnum
].locate
.offset
.constant
+ 1;
3653 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
3655 lower_bound
= argvec
[argnum
].locate
.offset
.constant
;
3656 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
3660 /* Don't worry about things in the fixed argument area;
3661 it has already been saved. */
3662 if (i
< reg_parm_stack_space
)
3663 i
= reg_parm_stack_space
;
3664 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
3667 if (i
< upper_bound
)
3669 /* We need to make a save area. */
3671 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
3672 enum machine_mode save_mode
3673 = mode_for_size (size
, MODE_INT
, 1);
3675 = plus_constant (argblock
,
3676 argvec
[argnum
].locate
.offset
.constant
);
3678 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
3680 if (save_mode
== BLKmode
)
3682 argvec
[argnum
].save_area
3683 = assign_stack_temp (BLKmode
,
3684 argvec
[argnum
].locate
.size
.constant
,
3687 emit_block_move (validize_mem (argvec
[argnum
].save_area
),
3689 GEN_INT (argvec
[argnum
].locate
.size
.constant
),
3690 BLOCK_OP_CALL_PARM
);
3694 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3696 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3701 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, PARM_BOUNDARY
,
3702 partial
, reg
, 0, argblock
,
3703 GEN_INT (argvec
[argnum
].locate
.offset
.constant
),
3704 reg_parm_stack_space
,
3705 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
));
3707 /* Now mark the segment we just used. */
3708 if (ACCUMULATE_OUTGOING_ARGS
)
3709 for (i
= lower_bound
; i
< upper_bound
; i
++)
3710 stack_usage_map
[i
] = 1;
3716 /* If we pushed args in forward order, perform stack alignment
3717 after pushing the last arg. */
3718 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3719 anti_adjust_stack (GEN_INT (args_size
.constant
3720 - original_args_size
.constant
));
3722 if (PUSH_ARGS_REVERSED
)
3727 fun
= prepare_call_address (fun
, NULL
, &call_fusage
, 0, 0);
3729 /* Now load any reg parms into their regs. */
3731 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3732 are to be pushed. */
3733 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3735 enum machine_mode mode
= argvec
[argnum
].mode
;
3736 rtx val
= argvec
[argnum
].value
;
3737 rtx reg
= argvec
[argnum
].reg
;
3738 int partial
= argvec
[argnum
].partial
;
3740 /* Handle calls that pass values in multiple non-contiguous
3741 locations. The PA64 has examples of this for library calls. */
3742 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3743 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
3744 else if (reg
!= 0 && partial
== 0)
3745 emit_move_insn (reg
, val
);
3750 /* Any regs containing parms remain in use through the call. */
3751 for (count
= 0; count
< nargs
; count
++)
3753 rtx reg
= argvec
[count
].reg
;
3754 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3755 use_group_regs (&call_fusage
, reg
);
3757 use_reg (&call_fusage
, reg
);
3760 /* Pass the function the address in which to return a structure value. */
3761 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
3763 emit_move_insn (struct_value
,
3765 force_operand (XEXP (mem_value
, 0),
3767 if (REG_P (struct_value
))
3768 use_reg (&call_fusage
, struct_value
);
3771 /* Don't allow popping to be deferred, since then
3772 cse'ing of library calls could delete a call and leave the pop. */
3774 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
3775 ? hard_libcall_value (outmode
) : NULL_RTX
);
3777 /* Stack must be properly aligned now. */
3778 if (stack_pointer_delta
& (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1))
3781 before_call
= get_last_insn ();
3783 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3784 will set inhibit_defer_pop to that value. */
3785 /* The return type is needed to decide how many bytes the function pops.
3786 Signedness plays no role in that, so for simplicity, we pretend it's
3787 always signed. We also assume that the list of arguments passed has
3788 no impact, so we pretend it is unknown. */
3790 emit_call_1 (fun
, NULL
,
3791 get_identifier (XSTR (orgfun
, 0)),
3792 build_function_type (tfom
, NULL_TREE
),
3793 original_args_size
.constant
, args_size
.constant
,
3795 FUNCTION_ARG (args_so_far
, VOIDmode
, void_type_node
, 1),
3797 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, & args_so_far
);
3799 /* For calls to `setjmp', etc., inform flow.c it should complain
3800 if nonvolatile values are live. For functions that cannot return,
3801 inform flow that control does not fall through. */
3803 if (flags
& (ECF_NORETURN
| ECF_LONGJMP
))
3805 /* The barrier note must be emitted
3806 immediately after the CALL_INSN. Some ports emit more than
3807 just a CALL_INSN above, so we must search for it here. */
3809 rtx last
= get_last_insn ();
3810 while (!CALL_P (last
))
3812 last
= PREV_INSN (last
);
3813 /* There was no CALL_INSN? */
3814 if (last
== before_call
)
3818 emit_barrier_after (last
);
3821 /* Now restore inhibit_defer_pop to its actual original value. */
3824 /* If call is cse'able, make appropriate pair of reg-notes around it.
3825 Test valreg so we don't crash; may safely ignore `const'
3826 if return type is void. Disable for PARALLEL return values, because
3827 we have no way to move such values into a pseudo register. */
3828 if (flags
& ECF_LIBCALL_BLOCK
)
3834 insns
= get_insns ();
3844 if (GET_CODE (valreg
) == PARALLEL
)
3846 temp
= gen_reg_rtx (outmode
);
3847 emit_group_store (temp
, valreg
, NULL_TREE
,
3848 GET_MODE_SIZE (outmode
));
3852 temp
= gen_reg_rtx (GET_MODE (valreg
));
3854 /* Construct an "equal form" for the value which mentions all the
3855 arguments in order as well as the function name. */
3856 for (i
= 0; i
< nargs
; i
++)
3857 note
= gen_rtx_EXPR_LIST (VOIDmode
, argvec
[i
].value
, note
);
3858 note
= gen_rtx_EXPR_LIST (VOIDmode
, fun
, note
);
3860 insns
= get_insns ();
3863 if (flags
& ECF_PURE
)
3864 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3865 gen_rtx_USE (VOIDmode
,
3866 gen_rtx_MEM (BLKmode
,
3867 gen_rtx_SCRATCH (VOIDmode
))),
3870 emit_libcall_block (insns
, temp
, valreg
, note
);
3877 /* Copy the value to the right place. */
3878 if (outmode
!= VOIDmode
&& retval
)
3884 if (value
!= mem_value
)
3885 emit_move_insn (value
, mem_value
);
3887 else if (GET_CODE (valreg
) == PARALLEL
)
3890 value
= gen_reg_rtx (outmode
);
3891 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
3893 else if (value
!= 0)
3894 emit_move_insn (value
, valreg
);
3899 if (ACCUMULATE_OUTGOING_ARGS
)
3901 #ifdef REG_PARM_STACK_SPACE
3903 restore_fixed_argument_area (save_area
, argblock
,
3904 high_to_save
, low_to_save
);
3907 /* If we saved any argument areas, restore them. */
3908 for (count
= 0; count
< nargs
; count
++)
3909 if (argvec
[count
].save_area
)
3911 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
3912 rtx adr
= plus_constant (argblock
,
3913 argvec
[count
].locate
.offset
.constant
);
3914 rtx stack_area
= gen_rtx_MEM (save_mode
,
3915 memory_address (save_mode
, adr
));
3917 if (save_mode
== BLKmode
)
3918 emit_block_move (stack_area
,
3919 validize_mem (argvec
[count
].save_area
),
3920 GEN_INT (argvec
[count
].locate
.size
.constant
),
3921 BLOCK_OP_CALL_PARM
);
3923 emit_move_insn (stack_area
, argvec
[count
].save_area
);
3926 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3927 stack_usage_map
= initial_stack_usage_map
;
3934 /* Output a library call to function FUN (a SYMBOL_REF rtx)
3935 (emitting the queue unless NO_QUEUE is nonzero),
3936 for a value of mode OUTMODE,
3937 with NARGS different arguments, passed as alternating rtx values
3938 and machine_modes to convert them to.
3940 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
3941 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
3942 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
3943 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
3944 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
3945 or other LCT_ value for other types of library calls. */
3948 emit_library_call (rtx orgfun
, enum libcall_type fn_type
,
3949 enum machine_mode outmode
, int nargs
, ...)
3953 va_start (p
, nargs
);
3954 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
3958 /* Like emit_library_call except that an extra argument, VALUE,
3959 comes second and says where to store the result.
3960 (If VALUE is zero, this function chooses a convenient way
3961 to return the value.
3963 This function returns an rtx for where the value is to be found.
3964 If VALUE is nonzero, VALUE is returned. */
3967 emit_library_call_value (rtx orgfun
, rtx value
,
3968 enum libcall_type fn_type
,
3969 enum machine_mode outmode
, int nargs
, ...)
3974 va_start (p
, nargs
);
3975 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
3982 /* Store a single argument for a function call
3983 into the register or memory area where it must be passed.
3984 *ARG describes the argument value and where to pass it.
3986 ARGBLOCK is the address of the stack-block for all the arguments,
3987 or 0 on a machine where arguments are pushed individually.
3989 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
3990 so must be careful about how the stack is used.
3992 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
3993 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
3994 that we need not worry about saving and restoring the stack.
3996 FNDECL is the declaration of the function we are calling.
3998 Return nonzero if this arg should cause sibcall failure,
4002 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
4003 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
4005 tree pval
= arg
->tree_value
;
4009 int i
, lower_bound
= 0, upper_bound
= 0;
4010 int sibcall_failure
= 0;
4012 if (TREE_CODE (pval
) == ERROR_MARK
)
4015 /* Push a new temporary level for any temporaries we make for
4019 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4021 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4022 save any previous data at that location. */
4023 if (argblock
&& ! variable_size
&& arg
->stack
)
4025 #ifdef ARGS_GROW_DOWNWARD
4026 /* stack_slot is negative, but we want to index stack_usage_map
4027 with positive values. */
4028 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4029 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4033 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
4035 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4036 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4040 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
4044 /* Don't worry about things in the fixed argument area;
4045 it has already been saved. */
4046 if (i
< reg_parm_stack_space
)
4047 i
= reg_parm_stack_space
;
4048 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
4051 if (i
< upper_bound
)
4053 /* We need to make a save area. */
4054 unsigned int size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
4055 enum machine_mode save_mode
= mode_for_size (size
, MODE_INT
, 1);
4056 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
4057 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
4059 if (save_mode
== BLKmode
)
4061 tree ot
= TREE_TYPE (arg
->tree_value
);
4062 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4063 | TYPE_QUAL_CONST
));
4065 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4066 preserve_temp_slots (arg
->save_area
);
4067 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4068 expr_size (arg
->tree_value
),
4069 BLOCK_OP_CALL_PARM
);
4073 arg
->save_area
= gen_reg_rtx (save_mode
);
4074 emit_move_insn (arg
->save_area
, stack_area
);
4080 /* If this isn't going to be placed on both the stack and in registers,
4081 set up the register and number of words. */
4082 if (! arg
->pass_on_stack
)
4084 if (flags
& ECF_SIBCALL
)
4085 reg
= arg
->tail_call_reg
;
4088 partial
= arg
->partial
;
4091 if (reg
!= 0 && partial
== 0)
4092 /* Being passed entirely in a register. We shouldn't be called in
4096 /* If this arg needs special alignment, don't load the registers
4098 if (arg
->n_aligned_regs
!= 0)
4101 /* If this is being passed partially in a register, we can't evaluate
4102 it directly into its stack slot. Otherwise, we can. */
4103 if (arg
->value
== 0)
4105 /* stack_arg_under_construction is nonzero if a function argument is
4106 being evaluated directly into the outgoing argument list and
4107 expand_call must take special action to preserve the argument list
4108 if it is called recursively.
4110 For scalar function arguments stack_usage_map is sufficient to
4111 determine which stack slots must be saved and restored. Scalar
4112 arguments in general have pass_on_stack == 0.
4114 If this argument is initialized by a function which takes the
4115 address of the argument (a C++ constructor or a C function
4116 returning a BLKmode structure), then stack_usage_map is
4117 insufficient and expand_call must push the stack around the
4118 function call. Such arguments have pass_on_stack == 1.
4120 Note that it is always safe to set stack_arg_under_construction,
4121 but this generates suboptimal code if set when not needed. */
4123 if (arg
->pass_on_stack
)
4124 stack_arg_under_construction
++;
4126 arg
->value
= expand_expr (pval
,
4128 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4129 ? NULL_RTX
: arg
->stack
,
4130 VOIDmode
, EXPAND_STACK_PARM
);
4132 /* If we are promoting object (or for any other reason) the mode
4133 doesn't agree, convert the mode. */
4135 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4136 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4137 arg
->value
, arg
->unsignedp
);
4139 if (arg
->pass_on_stack
)
4140 stack_arg_under_construction
--;
4143 /* Don't allow anything left on stack from computation
4144 of argument to alloca. */
4145 if (flags
& ECF_MAY_BE_ALLOCA
)
4146 do_pending_stack_adjust ();
4148 if (arg
->value
== arg
->stack
)
4149 /* If the value is already in the stack slot, we are done. */
4151 else if (arg
->mode
!= BLKmode
)
4155 /* Argument is a scalar, not entirely passed in registers.
4156 (If part is passed in registers, arg->partial says how much
4157 and emit_push_insn will take care of putting it there.)
4159 Push it, and if its size is less than the
4160 amount of space allocated to it,
4161 also bump stack pointer by the additional space.
4162 Note that in C the default argument promotions
4163 will prevent such mismatches. */
4165 size
= GET_MODE_SIZE (arg
->mode
);
4166 /* Compute how much space the push instruction will push.
4167 On many machines, pushing a byte will advance the stack
4168 pointer by a halfword. */
4169 #ifdef PUSH_ROUNDING
4170 size
= PUSH_ROUNDING (size
);
4174 /* Compute how much space the argument should get:
4175 round up to a multiple of the alignment for arguments. */
4176 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4177 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4178 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4179 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4181 /* This isn't already where we want it on the stack, so put it there.
4182 This can either be done with push or copy insns. */
4183 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
,
4184 PARM_BOUNDARY
, partial
, reg
, used
- size
, argblock
,
4185 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4186 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4188 /* Unless this is a partially-in-register argument, the argument is now
4191 arg
->value
= arg
->stack
;
4195 /* BLKmode, at least partly to be pushed. */
4197 unsigned int parm_align
;
4201 /* Pushing a nonscalar.
4202 If part is passed in registers, PARTIAL says how much
4203 and emit_push_insn will take care of putting it there. */
4205 /* Round its size up to a multiple
4206 of the allocation unit for arguments. */
4208 if (arg
->locate
.size
.var
!= 0)
4211 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
4215 /* PUSH_ROUNDING has no effect on us, because
4216 emit_push_insn for BLKmode is careful to avoid it. */
4217 if (reg
&& GET_CODE (reg
) == PARALLEL
)
4219 /* Use the size of the elt to compute excess. */
4220 rtx elt
= XEXP (XVECEXP (reg
, 0, 0), 0);
4221 excess
= (arg
->locate
.size
.constant
4222 - int_size_in_bytes (TREE_TYPE (pval
))
4223 + partial
* GET_MODE_SIZE (GET_MODE (elt
)));
4226 excess
= (arg
->locate
.size
.constant
4227 - int_size_in_bytes (TREE_TYPE (pval
))
4228 + partial
* UNITS_PER_WORD
);
4229 size_rtx
= expand_expr (size_in_bytes (TREE_TYPE (pval
)),
4230 NULL_RTX
, TYPE_MODE (sizetype
), 0);
4233 /* Some types will require stricter alignment, which will be
4234 provided for elsewhere in argument layout. */
4235 parm_align
= MAX (PARM_BOUNDARY
, TYPE_ALIGN (TREE_TYPE (pval
)));
4237 /* When an argument is padded down, the block is aligned to
4238 PARM_BOUNDARY, but the actual argument isn't. */
4239 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4241 if (arg
->locate
.size
.var
)
4242 parm_align
= BITS_PER_UNIT
;
4245 unsigned int excess_align
= (excess
& -excess
) * BITS_PER_UNIT
;
4246 parm_align
= MIN (parm_align
, excess_align
);
4250 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
4252 /* emit_push_insn might not work properly if arg->value and
4253 argblock + arg->locate.offset areas overlap. */
4257 if (XEXP (x
, 0) == current_function_internal_arg_pointer
4258 || (GET_CODE (XEXP (x
, 0)) == PLUS
4259 && XEXP (XEXP (x
, 0), 0) ==
4260 current_function_internal_arg_pointer
4261 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
))
4263 if (XEXP (x
, 0) != current_function_internal_arg_pointer
)
4264 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4266 /* expand_call should ensure this. */
4267 if (arg
->locate
.offset
.var
|| GET_CODE (size_rtx
) != CONST_INT
)
4270 if (arg
->locate
.offset
.constant
> i
)
4272 if (arg
->locate
.offset
.constant
< i
+ INTVAL (size_rtx
))
4273 sibcall_failure
= 1;
4275 else if (arg
->locate
.offset
.constant
< i
)
4277 if (i
< arg
->locate
.offset
.constant
+ INTVAL (size_rtx
))
4278 sibcall_failure
= 1;
4283 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4284 parm_align
, partial
, reg
, excess
, argblock
,
4285 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4286 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4288 /* Unless this is a partially-in-register argument, the argument is now
4291 ??? Unlike the case above, in which we want the actual
4292 address of the data, so that we can load it directly into a
4293 register, here we want the address of the stack slot, so that
4294 it's properly aligned for word-by-word copying or something
4295 like that. It's not clear that this is always correct. */
4297 arg
->value
= arg
->stack_slot
;
4300 /* Mark all slots this store used. */
4301 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
4302 && argblock
&& ! variable_size
&& arg
->stack
)
4303 for (i
= lower_bound
; i
< upper_bound
; i
++)
4304 stack_usage_map
[i
] = 1;
4306 /* Once we have pushed something, pops can't safely
4307 be deferred during the rest of the arguments. */
4310 /* Free any temporary slots made in processing this argument. Show
4311 that we might have taken the address of something and pushed that
4313 preserve_temp_slots (NULL_RTX
);
4317 return sibcall_failure
;
4320 /* Nonzero if we do not know how to pass TYPE solely in registers. */
4323 must_pass_in_stack_var_size (enum machine_mode mode ATTRIBUTE_UNUSED
,
4329 /* If the type has variable size... */
4330 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4333 /* If the type is marked as addressable (it is required
4334 to be constructed into the stack)... */
4335 if (TREE_ADDRESSABLE (type
))
4341 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
4342 takes trailing padding of a structure into account. */
4343 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
4346 must_pass_in_stack_var_size_or_pad (enum machine_mode mode
, tree type
)
4351 /* If the type has variable size... */
4352 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4355 /* If the type is marked as addressable (it is required
4356 to be constructed into the stack)... */
4357 if (TREE_ADDRESSABLE (type
))
4360 /* If the padding and mode of the type is such that a copy into
4361 a register would put it into the wrong part of the register. */
4363 && int_size_in_bytes (type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
4364 && (FUNCTION_ARG_PADDING (mode
, type
)
4365 == (BYTES_BIG_ENDIAN
? upward
: downward
)))