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 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
36 #include "langhooks.h"
39 #if !defined FUNCTION_OK_FOR_SIBCALL
40 #define FUNCTION_OK_FOR_SIBCALL(DECL) 1
43 /* Decide whether a function's arguments should be processed
44 from first to last or from last to first.
46 They should if the stack and args grow in opposite directions, but
47 only if we have push insns. */
51 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
52 #define PUSH_ARGS_REVERSED PUSH_ARGS
57 #ifndef PUSH_ARGS_REVERSED
58 #define PUSH_ARGS_REVERSED 0
61 #ifndef STACK_POINTER_OFFSET
62 #define STACK_POINTER_OFFSET 0
65 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
66 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
68 /* Data structure and subroutines used within expand_call. */
72 /* Tree node for this argument. */
74 /* Mode for value; TYPE_MODE unless promoted. */
75 enum machine_mode mode
;
76 /* Current RTL value for argument, or 0 if it isn't precomputed. */
78 /* Initially-compute RTL value for argument; only for const functions. */
80 /* Register to pass this argument in, 0 if passed on stack, or an
81 PARALLEL if the arg is to be copied into multiple non-contiguous
84 /* Register to pass this argument in when generating tail call sequence.
85 This is not the same register as for normal calls on machines with
88 /* If REG was promoted from the actual mode of the argument expression,
89 indicates whether the promotion is sign- or zero-extended. */
91 /* Number of registers to use. 0 means put the whole arg in registers.
92 Also 0 if not passed in registers. */
94 /* Nonzero if argument must be passed on stack.
95 Note that some arguments may be passed on the stack
96 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
97 pass_on_stack identifies arguments that *cannot* go in registers. */
99 /* Offset of this argument from beginning of stack-args. */
100 struct args_size offset
;
101 /* Similar, but offset to the start of the stack slot. Different from
102 OFFSET if this arg pads downward. */
103 struct args_size slot_offset
;
104 /* Size of this argument on the stack, rounded up for any padding it gets,
105 parts of the argument passed in registers do not count.
106 If REG_PARM_STACK_SPACE is defined, then register parms
107 are counted here as well. */
108 struct args_size size
;
109 /* Location on the stack at which parameter should be stored. The store
110 has already been done if STACK == VALUE. */
112 /* Location on the stack of the start of this argument slot. This can
113 differ from STACK if this arg pads downward. This location is known
114 to be aligned to FUNCTION_ARG_BOUNDARY. */
116 /* Place that this stack area has been saved, if needed. */
118 /* If an argument's alignment does not permit direct copying into registers,
119 copy in smaller-sized pieces into pseudos. These are stored in a
120 block pointed to by this field. The next field says how many
121 word-sized pseudos we made. */
124 /* The amount that the stack pointer needs to be adjusted to
125 force alignment for the next argument. */
126 struct args_size alignment_pad
;
129 /* A vector of one char per byte of stack space. A byte if nonzero if
130 the corresponding stack location has been used.
131 This vector is used to prevent a function call within an argument from
132 clobbering any stack already set up. */
133 static char *stack_usage_map
;
135 /* Size of STACK_USAGE_MAP. */
136 static int highest_outgoing_arg_in_use
;
138 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
139 stack location's tail call argument has been already stored into the stack.
140 This bitmap is used to prevent sibling call optimization if function tries
141 to use parent's incoming argument slots when they have been already
142 overwritten with tail call arguments. */
143 static sbitmap stored_args_map
;
145 /* stack_arg_under_construction is nonzero when an argument may be
146 initialized with a constructor call (including a C function that
147 returns a BLKmode struct) and expand_call must take special action
148 to make sure the object being constructed does not overlap the
149 argument list for the constructor call. */
150 int stack_arg_under_construction
;
152 static int calls_function
PARAMS ((tree
, int));
153 static int calls_function_1
PARAMS ((tree
, int));
155 /* Nonzero if this is a call to a `const' function. */
157 /* Nonzero if this is a call to a `volatile' function. */
158 #define ECF_NORETURN 2
159 /* Nonzero if this is a call to malloc or a related function. */
161 /* Nonzero if it is plausible that this is a call to alloca. */
162 #define ECF_MAY_BE_ALLOCA 8
163 /* Nonzero if this is a call to a function that won't throw an exception. */
164 #define ECF_NOTHROW 16
165 /* Nonzero if this is a call to setjmp or a related function. */
166 #define ECF_RETURNS_TWICE 32
167 /* Nonzero if this is a call to `longjmp'. */
168 #define ECF_LONGJMP 64
169 /* Nonzero if this is a syscall that makes a new process in the image of
171 #define ECF_FORK_OR_EXEC 128
172 #define ECF_SIBCALL 256
173 /* Nonzero if this is a call to "pure" function (like const function,
174 but may read memory. */
176 /* Nonzero if this is a call to a function that returns with the stack
177 pointer depressed. */
178 #define ECF_SP_DEPRESSED 1024
179 /* Nonzero if this call is known to always return. */
180 #define ECF_ALWAYS_RETURN 2048
181 /* Create libcall block around the call. */
182 #define ECF_LIBCALL_BLOCK 4096
184 static void emit_call_1
PARAMS ((rtx
, tree
, tree
, HOST_WIDE_INT
,
185 HOST_WIDE_INT
, HOST_WIDE_INT
, rtx
,
188 static void precompute_register_parameters
PARAMS ((int,
191 static int store_one_arg
PARAMS ((struct arg_data
*, rtx
, int, int,
193 static void store_unaligned_arguments_into_pseudos
PARAMS ((struct arg_data
*,
195 static int finalize_must_preallocate
PARAMS ((int, int,
197 struct args_size
*));
198 static void precompute_arguments
PARAMS ((int, int,
200 static int compute_argument_block_size
PARAMS ((int,
203 static void initialize_argument_information
PARAMS ((int,
210 static void compute_argument_addresses
PARAMS ((struct arg_data
*,
212 static rtx rtx_for_function_call
PARAMS ((tree
, tree
));
213 static void load_register_parameters
PARAMS ((struct arg_data
*,
215 static rtx emit_library_call_value_1
PARAMS ((int, rtx
, rtx
,
219 static int special_function_p
PARAMS ((tree
, int));
220 static int flags_from_decl_or_type
PARAMS ((tree
));
221 static rtx try_to_integrate
PARAMS ((tree
, tree
, rtx
,
223 static int check_sibcall_argument_overlap_1
PARAMS ((rtx
));
224 static int check_sibcall_argument_overlap
PARAMS ((rtx
, struct arg_data
*));
226 static int combine_pending_stack_adjustment_and_call
227 PARAMS ((int, struct args_size
*, int));
229 #ifdef REG_PARM_STACK_SPACE
230 static rtx save_fixed_argument_area
PARAMS ((int, rtx
, int *, int *));
231 static void restore_fixed_argument_area
PARAMS ((rtx
, rtx
, int, int));
234 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
237 If WHICH is 0, return 1 if EXP contains a call to any function.
238 Actually, we only need return 1 if evaluating EXP would require pushing
239 arguments on the stack, but that is too difficult to compute, so we just
240 assume any function call might require the stack. */
242 static tree calls_function_save_exprs
;
245 calls_function (exp
, which
)
251 calls_function_save_exprs
= 0;
252 val
= calls_function_1 (exp
, which
);
253 calls_function_save_exprs
= 0;
257 /* Recursive function to do the work of above function. */
260 calls_function_1 (exp
, which
)
265 enum tree_code code
= TREE_CODE (exp
);
266 int class = TREE_CODE_CLASS (code
);
267 int length
= first_rtl_op (code
);
269 /* If this code is language-specific, we don't know what it will do. */
270 if ((int) code
>= NUM_TREE_CODES
)
278 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp
, 0))))
280 && (TYPE_RETURNS_STACK_DEPRESSED
281 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp
, 0))))))
283 else if (TREE_CODE (TREE_OPERAND (exp
, 0)) == ADDR_EXPR
284 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0))
286 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0),
288 & ECF_MAY_BE_ALLOCA
))
297 for (tem
= CONSTRUCTOR_ELTS (exp
); tem
!= 0; tem
= TREE_CHAIN (tem
))
298 if (calls_function_1 (TREE_VALUE (tem
), which
))
305 if (SAVE_EXPR_RTL (exp
) != 0)
307 if (value_member (exp
, calls_function_save_exprs
))
309 calls_function_save_exprs
= tree_cons (NULL_TREE
, exp
,
310 calls_function_save_exprs
);
311 return (TREE_OPERAND (exp
, 0) != 0
312 && calls_function_1 (TREE_OPERAND (exp
, 0), which
));
319 for (local
= BLOCK_VARS (exp
); local
; local
= TREE_CHAIN (local
))
320 if (DECL_INITIAL (local
) != 0
321 && calls_function_1 (DECL_INITIAL (local
), which
))
324 for (subblock
= BLOCK_SUBBLOCKS (exp
);
326 subblock
= TREE_CHAIN (subblock
))
327 if (calls_function_1 (subblock
, which
))
333 for (; exp
!= 0; exp
= TREE_CHAIN (exp
))
334 if (calls_function_1 (TREE_VALUE (exp
), which
))
342 /* Only expressions, references, and blocks can contain calls. */
343 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
346 for (i
= 0; i
< length
; i
++)
347 if (TREE_OPERAND (exp
, i
) != 0
348 && calls_function_1 (TREE_OPERAND (exp
, i
), which
))
354 /* Force FUNEXP into a form suitable for the address of a CALL,
355 and return that as an rtx. Also load the static chain register
356 if FNDECL is a nested function.
358 CALL_FUSAGE points to a variable holding the prospective
359 CALL_INSN_FUNCTION_USAGE information. */
362 prepare_call_address (funexp
, fndecl
, call_fusage
, reg_parm_seen
, sibcallp
)
369 rtx static_chain_value
= 0;
371 funexp
= protect_from_queue (funexp
, 0);
374 /* Get possible static chain value for nested function in C. */
375 static_chain_value
= lookup_static_chain (fndecl
);
377 /* Make a valid memory address and copy constants thru pseudo-regs,
378 but not for a constant address if -fno-function-cse. */
379 if (GET_CODE (funexp
) != SYMBOL_REF
)
380 /* If we are using registers for parameters, force the
381 function address into a register now. */
382 funexp
= ((SMALL_REGISTER_CLASSES
&& reg_parm_seen
)
383 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
384 : memory_address (FUNCTION_MODE
, funexp
));
387 #ifndef NO_FUNCTION_CSE
388 if (optimize
&& ! flag_no_function_cse
)
389 #ifdef NO_RECURSIVE_FUNCTION_CSE
390 if (fndecl
!= current_function_decl
)
392 funexp
= force_reg (Pmode
, funexp
);
396 if (static_chain_value
!= 0)
398 emit_move_insn (static_chain_rtx
, static_chain_value
);
400 if (GET_CODE (static_chain_rtx
) == REG
)
401 use_reg (call_fusage
, static_chain_rtx
);
407 /* Generate instructions to call function FUNEXP,
408 and optionally pop the results.
409 The CALL_INSN is the first insn generated.
411 FNDECL is the declaration node of the function. This is given to the
412 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
414 FUNTYPE is the data type of the function. This is given to the macro
415 RETURN_POPS_ARGS to determine whether this function pops its own args.
416 We used to allow an identifier for library functions, but that doesn't
417 work when the return type is an aggregate type and the calling convention
418 says that the pointer to this aggregate is to be popped by the callee.
420 STACK_SIZE is the number of bytes of arguments on the stack,
421 ROUNDED_STACK_SIZE is that number rounded up to
422 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
423 both to put into the call insn and to generate explicit popping
426 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
427 It is zero if this call doesn't want a structure value.
429 NEXT_ARG_REG is the rtx that results from executing
430 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
431 just after all the args have had their registers assigned.
432 This could be whatever you like, but normally it is the first
433 arg-register beyond those used for args in this call,
434 or 0 if all the arg-registers are used in this call.
435 It is passed on to `gen_call' so you can put this info in the call insn.
437 VALREG is a hard register in which a value is returned,
438 or 0 if the call does not return a value.
440 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
441 the args to this call were processed.
442 We restore `inhibit_defer_pop' to that value.
444 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
445 denote registers used by the called function. */
448 emit_call_1 (funexp
, fndecl
, funtype
, stack_size
, rounded_stack_size
,
449 struct_value_size
, next_arg_reg
, valreg
, old_inhibit_defer_pop
,
450 call_fusage
, ecf_flags
, args_so_far
)
452 tree fndecl ATTRIBUTE_UNUSED
;
453 tree funtype ATTRIBUTE_UNUSED
;
454 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED
;
455 HOST_WIDE_INT rounded_stack_size
;
456 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED
;
457 rtx next_arg_reg ATTRIBUTE_UNUSED
;
459 int old_inhibit_defer_pop
;
462 CUMULATIVE_ARGS
*args_so_far ATTRIBUTE_UNUSED
;
464 rtx rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
466 int already_popped
= 0;
467 HOST_WIDE_INT n_popped
= RETURN_POPS_ARGS (fndecl
, funtype
, stack_size
);
468 #if defined (HAVE_call) && defined (HAVE_call_value)
469 rtx struct_value_size_rtx
;
470 struct_value_size_rtx
= GEN_INT (struct_value_size
);
473 #ifdef CALL_POPS_ARGS
474 n_popped
+= CALL_POPS_ARGS (* args_so_far
);
477 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
478 and we don't want to load it into a register as an optimization,
479 because prepare_call_address already did it if it should be done. */
480 if (GET_CODE (funexp
) != SYMBOL_REF
)
481 funexp
= memory_address (FUNCTION_MODE
, funexp
);
483 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
484 if ((ecf_flags
& ECF_SIBCALL
)
485 && HAVE_sibcall_pop
&& HAVE_sibcall_value_pop
486 && (n_popped
> 0 || stack_size
== 0))
488 rtx n_pop
= GEN_INT (n_popped
);
491 /* If this subroutine pops its own args, record that in the call insn
492 if possible, for the sake of frame pointer elimination. */
495 pat
= GEN_SIBCALL_VALUE_POP (valreg
,
496 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
497 rounded_stack_size_rtx
, next_arg_reg
,
500 pat
= GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
501 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
503 emit_call_insn (pat
);
509 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
510 /* If the target has "call" or "call_value" insns, then prefer them
511 if no arguments are actually popped. If the target does not have
512 "call" or "call_value" insns, then we must use the popping versions
513 even if the call has no arguments to pop. */
514 #if defined (HAVE_call) && defined (HAVE_call_value)
515 if (HAVE_call
&& HAVE_call_value
&& HAVE_call_pop
&& HAVE_call_value_pop
516 && n_popped
> 0 && ! (ecf_flags
& ECF_SP_DEPRESSED
))
518 if (HAVE_call_pop
&& HAVE_call_value_pop
)
521 rtx n_pop
= GEN_INT (n_popped
);
524 /* If this subroutine pops its own args, record that in the call insn
525 if possible, for the sake of frame pointer elimination. */
528 pat
= GEN_CALL_VALUE_POP (valreg
,
529 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
530 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
532 pat
= GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
533 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
535 emit_call_insn (pat
);
541 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
542 if ((ecf_flags
& ECF_SIBCALL
)
543 && HAVE_sibcall
&& HAVE_sibcall_value
)
546 emit_call_insn (GEN_SIBCALL_VALUE (valreg
,
547 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
548 rounded_stack_size_rtx
,
549 next_arg_reg
, NULL_RTX
));
551 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
552 rounded_stack_size_rtx
, next_arg_reg
,
553 struct_value_size_rtx
));
558 #if defined (HAVE_call) && defined (HAVE_call_value)
559 if (HAVE_call
&& HAVE_call_value
)
562 emit_call_insn (GEN_CALL_VALUE (valreg
,
563 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
564 rounded_stack_size_rtx
, next_arg_reg
,
567 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
568 rounded_stack_size_rtx
, next_arg_reg
,
569 struct_value_size_rtx
));
575 /* Find the CALL insn we just emitted. */
576 for (call_insn
= get_last_insn ();
577 call_insn
&& GET_CODE (call_insn
) != CALL_INSN
;
578 call_insn
= PREV_INSN (call_insn
))
584 /* Mark memory as used for "pure" function call. */
585 if (ecf_flags
& ECF_PURE
)
589 gen_rtx_USE (VOIDmode
,
590 gen_rtx_MEM (BLKmode
, gen_rtx_SCRATCH (VOIDmode
))),
593 /* Put the register usage information on the CALL. If there is already
594 some usage information, put ours at the end. */
595 if (CALL_INSN_FUNCTION_USAGE (call_insn
))
599 for (link
= CALL_INSN_FUNCTION_USAGE (call_insn
); XEXP (link
, 1) != 0;
600 link
= XEXP (link
, 1))
603 XEXP (link
, 1) = call_fusage
;
606 CALL_INSN_FUNCTION_USAGE (call_insn
) = call_fusage
;
608 /* If this is a const call, then set the insn's unchanging bit. */
609 if (ecf_flags
& (ECF_CONST
| ECF_PURE
))
610 CONST_OR_PURE_CALL_P (call_insn
) = 1;
612 /* If this call can't throw, attach a REG_EH_REGION reg note to that
614 if (ecf_flags
& ECF_NOTHROW
)
615 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_EH_REGION
, const0_rtx
,
616 REG_NOTES (call_insn
));
618 if (ecf_flags
& ECF_NORETURN
)
619 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_NORETURN
, const0_rtx
,
620 REG_NOTES (call_insn
));
621 if (ecf_flags
& ECF_ALWAYS_RETURN
)
622 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN
, const0_rtx
,
623 REG_NOTES (call_insn
));
625 if (ecf_flags
& ECF_RETURNS_TWICE
)
627 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_SETJMP
, const0_rtx
,
628 REG_NOTES (call_insn
));
629 current_function_calls_setjmp
= 1;
632 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
634 /* Restore this now, so that we do defer pops for this call's args
635 if the context of the call as a whole permits. */
636 inhibit_defer_pop
= old_inhibit_defer_pop
;
641 CALL_INSN_FUNCTION_USAGE (call_insn
)
642 = gen_rtx_EXPR_LIST (VOIDmode
,
643 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
644 CALL_INSN_FUNCTION_USAGE (call_insn
));
645 rounded_stack_size
-= n_popped
;
646 rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
647 stack_pointer_delta
-= n_popped
;
650 if (!ACCUMULATE_OUTGOING_ARGS
)
652 /* If returning from the subroutine does not automatically pop the args,
653 we need an instruction to pop them sooner or later.
654 Perhaps do it now; perhaps just record how much space to pop later.
656 If returning from the subroutine does pop the args, indicate that the
657 stack pointer will be changed. */
659 if (rounded_stack_size
!= 0)
661 if (ecf_flags
& ECF_SP_DEPRESSED
)
662 /* Just pretend we did the pop. */
663 stack_pointer_delta
-= rounded_stack_size
;
664 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
665 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
666 pending_stack_adjust
+= rounded_stack_size
;
668 adjust_stack (rounded_stack_size_rtx
);
671 /* When we accumulate outgoing args, we must avoid any stack manipulations.
672 Restore the stack pointer to its original value now. Usually
673 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
674 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
675 popping variants of functions exist as well.
677 ??? We may optimize similar to defer_pop above, but it is
678 probably not worthwhile.
680 ??? It will be worthwhile to enable combine_stack_adjustments even for
683 anti_adjust_stack (GEN_INT (n_popped
));
686 /* Determine if the function identified by NAME and FNDECL is one with
687 special properties we wish to know about.
689 For example, if the function might return more than one time (setjmp), then
690 set RETURNS_TWICE to a nonzero value.
692 Similarly set LONGJMP for if the function is in the longjmp family.
694 Set MALLOC for any of the standard memory allocation functions which
695 allocate from the heap.
697 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
698 space from the stack such as alloca. */
701 special_function_p (fndecl
, flags
)
705 if (! (flags
& ECF_MALLOC
)
706 && fndecl
&& DECL_NAME (fndecl
)
707 && IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) <= 17
708 /* Exclude functions not at the file scope, or not `extern',
709 since they are not the magic functions we would otherwise
711 && DECL_CONTEXT (fndecl
) == NULL_TREE
&& TREE_PUBLIC (fndecl
))
713 const char *name
= IDENTIFIER_POINTER (DECL_NAME (fndecl
));
714 const char *tname
= name
;
716 /* We assume that alloca will always be called by name. It
717 makes no sense to pass it as a pointer-to-function to
718 anything that does not understand its behavior. */
719 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 6
721 && ! strcmp (name
, "alloca"))
722 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 16
724 && ! strcmp (name
, "__builtin_alloca"))))
725 flags
|= ECF_MAY_BE_ALLOCA
;
727 /* Disregard prefix _, __ or __x. */
730 if (name
[1] == '_' && name
[2] == 'x')
732 else if (name
[1] == '_')
741 && (! strcmp (tname
, "setjmp")
742 || ! strcmp (tname
, "setjmp_syscall")))
744 && ! strcmp (tname
, "sigsetjmp"))
746 && ! strcmp (tname
, "savectx")))
747 flags
|= ECF_RETURNS_TWICE
;
750 && ! strcmp (tname
, "siglongjmp"))
751 flags
|= ECF_LONGJMP
;
753 else if ((tname
[0] == 'q' && tname
[1] == 's'
754 && ! strcmp (tname
, "qsetjmp"))
755 || (tname
[0] == 'v' && tname
[1] == 'f'
756 && ! strcmp (tname
, "vfork")))
757 flags
|= ECF_RETURNS_TWICE
;
759 else if (tname
[0] == 'l' && tname
[1] == 'o'
760 && ! strcmp (tname
, "longjmp"))
761 flags
|= ECF_LONGJMP
;
763 else if ((tname
[0] == 'f' && tname
[1] == 'o'
764 && ! strcmp (tname
, "fork"))
765 /* Linux specific: __clone. check NAME to insist on the
766 leading underscores, to avoid polluting the ISO / POSIX
768 || (name
[0] == '_' && name
[1] == '_'
769 && ! strcmp (tname
, "clone"))
770 || (tname
[0] == 'e' && tname
[1] == 'x' && tname
[2] == 'e'
771 && tname
[3] == 'c' && (tname
[4] == 'l' || tname
[4] == 'v')
773 || ((tname
[5] == 'p' || tname
[5] == 'e')
774 && tname
[6] == '\0'))))
775 flags
|= ECF_FORK_OR_EXEC
;
777 /* Do not add any more malloc-like functions to this list,
778 instead mark them as malloc functions using the malloc attribute.
779 Note, realloc is not suitable for attribute malloc since
780 it may return the same address across multiple calls.
781 C++ operator new is not suitable because it is not required
782 to return a unique pointer; indeed, the standard placement new
783 just returns its argument. */
784 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl
))) == Pmode
785 && (! strcmp (tname
, "malloc")
786 || ! strcmp (tname
, "calloc")
787 || ! strcmp (tname
, "strdup")))
793 /* Return nonzero when tree represent call to longjmp. */
796 setjmp_call_p (fndecl
)
799 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
802 /* Detect flags (function attributes) from the function decl or type node. */
805 flags_from_decl_or_type (exp
)
810 /* ??? We can't set IS_MALLOC for function types? */
813 type
= TREE_TYPE (exp
);
815 /* The function exp may have the `malloc' attribute. */
816 if (DECL_P (exp
) && DECL_IS_MALLOC (exp
))
819 /* The function exp may have the `pure' attribute. */
820 if (DECL_P (exp
) && DECL_IS_PURE (exp
))
821 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
823 if (TREE_NOTHROW (exp
))
824 flags
|= ECF_NOTHROW
;
827 if (TREE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
828 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
830 if (TREE_THIS_VOLATILE (exp
))
831 flags
|= ECF_NORETURN
;
833 /* Mark if the function returns with the stack pointer depressed. We
834 cannot consider it pure or constant in that case. */
835 if (TREE_CODE (type
) == FUNCTION_TYPE
&& TYPE_RETURNS_STACK_DEPRESSED (type
))
837 flags
|= ECF_SP_DEPRESSED
;
838 flags
&= ~(ECF_PURE
| ECF_CONST
| ECF_LIBCALL_BLOCK
);
844 /* Precompute all register parameters as described by ARGS, storing values
845 into fields within the ARGS array.
847 NUM_ACTUALS indicates the total number elements in the ARGS array.
849 Set REG_PARM_SEEN if we encounter a register parameter. */
852 precompute_register_parameters (num_actuals
, args
, reg_parm_seen
)
854 struct arg_data
*args
;
861 for (i
= 0; i
< num_actuals
; i
++)
862 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
866 if (args
[i
].value
== 0)
869 args
[i
].value
= expand_expr (args
[i
].tree_value
, NULL_RTX
,
871 preserve_temp_slots (args
[i
].value
);
874 /* ANSI doesn't require a sequence point here,
875 but PCC has one, so this will avoid some problems. */
879 /* If the value is a non-legitimate constant, force it into a
880 pseudo now. TLS symbols sometimes need a call to resolve. */
881 if (CONSTANT_P (args
[i
].value
)
882 && !LEGITIMATE_CONSTANT_P (args
[i
].value
))
883 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
885 /* If we are to promote the function arg to a wider mode,
888 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
890 = convert_modes (args
[i
].mode
,
891 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
892 args
[i
].value
, args
[i
].unsignedp
);
894 /* If the value is expensive, and we are inside an appropriately
895 short loop, put the value into a pseudo and then put the pseudo
898 For small register classes, also do this if this call uses
899 register parameters. This is to avoid reload conflicts while
900 loading the parameters registers. */
902 if ((! (GET_CODE (args
[i
].value
) == REG
903 || (GET_CODE (args
[i
].value
) == SUBREG
904 && GET_CODE (SUBREG_REG (args
[i
].value
)) == REG
)))
905 && args
[i
].mode
!= BLKmode
906 && rtx_cost (args
[i
].value
, SET
) > COSTS_N_INSNS (1)
907 && ((SMALL_REGISTER_CLASSES
&& *reg_parm_seen
)
908 || preserve_subexpressions_p ()))
909 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
913 #ifdef REG_PARM_STACK_SPACE
915 /* The argument list is the property of the called routine and it
916 may clobber it. If the fixed area has been used for previous
917 parameters, we must save and restore it. */
920 save_fixed_argument_area (reg_parm_stack_space
, argblock
,
921 low_to_save
, high_to_save
)
922 int reg_parm_stack_space
;
928 rtx save_area
= NULL_RTX
;
930 /* Compute the boundary of the that needs to be saved, if any. */
931 #ifdef ARGS_GROW_DOWNWARD
932 for (i
= 0; i
< reg_parm_stack_space
+ 1; i
++)
934 for (i
= 0; i
< reg_parm_stack_space
; i
++)
937 if (i
>= highest_outgoing_arg_in_use
938 || stack_usage_map
[i
] == 0)
941 if (*low_to_save
== -1)
947 if (*low_to_save
>= 0)
949 int num_to_save
= *high_to_save
- *low_to_save
+ 1;
950 enum machine_mode save_mode
951 = mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
954 /* If we don't have the required alignment, must do this in BLKmode. */
955 if ((*low_to_save
& (MIN (GET_MODE_SIZE (save_mode
),
956 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
959 #ifdef ARGS_GROW_DOWNWARD
961 = gen_rtx_MEM (save_mode
,
962 memory_address (save_mode
,
963 plus_constant (argblock
,
966 stack_area
= gen_rtx_MEM (save_mode
,
967 memory_address (save_mode
,
968 plus_constant (argblock
,
972 set_mem_align (stack_area
, PARM_BOUNDARY
);
973 if (save_mode
== BLKmode
)
975 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
976 emit_block_move (validize_mem (save_area
), stack_area
,
977 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
981 save_area
= gen_reg_rtx (save_mode
);
982 emit_move_insn (save_area
, stack_area
);
990 restore_fixed_argument_area (save_area
, argblock
, high_to_save
, low_to_save
)
996 enum machine_mode save_mode
= GET_MODE (save_area
);
997 #ifdef ARGS_GROW_DOWNWARD
999 = gen_rtx_MEM (save_mode
,
1000 memory_address (save_mode
,
1001 plus_constant (argblock
,
1005 = gen_rtx_MEM (save_mode
,
1006 memory_address (save_mode
,
1007 plus_constant (argblock
,
1011 if (save_mode
!= BLKmode
)
1012 emit_move_insn (stack_area
, save_area
);
1014 emit_block_move (stack_area
, validize_mem (save_area
),
1015 GEN_INT (high_to_save
- low_to_save
+ 1),
1016 BLOCK_OP_CALL_PARM
);
1018 #endif /* REG_PARM_STACK_SPACE */
1020 /* If any elements in ARGS refer to parameters that are to be passed in
1021 registers, but not in memory, and whose alignment does not permit a
1022 direct copy into registers. Copy the values into a group of pseudos
1023 which we will later copy into the appropriate hard registers.
1025 Pseudos for each unaligned argument will be stored into the array
1026 args[argnum].aligned_regs. The caller is responsible for deallocating
1027 the aligned_regs array if it is nonzero. */
1030 store_unaligned_arguments_into_pseudos (args
, num_actuals
)
1031 struct arg_data
*args
;
1036 for (i
= 0; i
< num_actuals
; i
++)
1037 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
1038 && args
[i
].mode
== BLKmode
1039 && (TYPE_ALIGN (TREE_TYPE (args
[i
].tree_value
))
1040 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
1042 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1043 int big_endian_correction
= 0;
1045 args
[i
].n_aligned_regs
1046 = args
[i
].partial
? args
[i
].partial
1047 : (bytes
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1049 args
[i
].aligned_regs
= (rtx
*) xmalloc (sizeof (rtx
)
1050 * args
[i
].n_aligned_regs
);
1052 /* Structures smaller than a word are aligned to the least
1053 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1054 this means we must skip the empty high order bytes when
1055 calculating the bit offset. */
1056 if (BYTES_BIG_ENDIAN
1057 && !FUNCTION_ARG_REG_LITTLE_ENDIAN
1058 && bytes
< UNITS_PER_WORD
)
1059 big_endian_correction
= (BITS_PER_WORD
- (bytes
* BITS_PER_UNIT
));
1061 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1063 rtx reg
= gen_reg_rtx (word_mode
);
1064 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
1065 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
1067 args
[i
].aligned_regs
[j
] = reg
;
1069 /* There is no need to restrict this code to loading items
1070 in TYPE_ALIGN sized hunks. The bitfield instructions can
1071 load up entire word sized registers efficiently.
1073 ??? This may not be needed anymore.
1074 We use to emit a clobber here but that doesn't let later
1075 passes optimize the instructions we emit. By storing 0 into
1076 the register later passes know the first AND to zero out the
1077 bitfield being set in the register is unnecessary. The store
1078 of 0 will be deleted as will at least the first AND. */
1080 emit_move_insn (reg
, const0_rtx
);
1082 bytes
-= bitsize
/ BITS_PER_UNIT
;
1083 store_bit_field (reg
, bitsize
, big_endian_correction
, word_mode
,
1084 extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
1085 word_mode
, word_mode
,
1092 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1095 NUM_ACTUALS is the total number of parameters.
1097 N_NAMED_ARGS is the total number of named arguments.
1099 FNDECL is the tree code for the target of this call (if known)
1101 ARGS_SO_FAR holds state needed by the target to know where to place
1104 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1105 for arguments which are passed in registers.
1107 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1108 and may be modified by this routine.
1110 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1111 flags which may may be modified by this routine. */
1114 initialize_argument_information (num_actuals
, args
, args_size
, n_named_args
,
1115 actparms
, fndecl
, args_so_far
,
1116 reg_parm_stack_space
, old_stack_level
,
1117 old_pending_adj
, must_preallocate
,
1119 int num_actuals ATTRIBUTE_UNUSED
;
1120 struct arg_data
*args
;
1121 struct args_size
*args_size
;
1122 int n_named_args ATTRIBUTE_UNUSED
;
1125 CUMULATIVE_ARGS
*args_so_far
;
1126 int reg_parm_stack_space
;
1127 rtx
*old_stack_level
;
1128 int *old_pending_adj
;
1129 int *must_preallocate
;
1132 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1135 /* Count arg position in order args appear. */
1138 struct args_size alignment_pad
;
1142 args_size
->constant
= 0;
1145 /* In this loop, we consider args in the order they are written.
1146 We fill up ARGS from the front or from the back if necessary
1147 so that in any case the first arg to be pushed ends up at the front. */
1149 if (PUSH_ARGS_REVERSED
)
1151 i
= num_actuals
- 1, inc
= -1;
1152 /* In this case, must reverse order of args
1153 so that we compute and push the last arg first. */
1160 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1161 for (p
= actparms
, argpos
= 0; p
; p
= TREE_CHAIN (p
), i
+= inc
, argpos
++)
1163 tree type
= TREE_TYPE (TREE_VALUE (p
));
1165 enum machine_mode mode
;
1167 args
[i
].tree_value
= TREE_VALUE (p
);
1169 /* Replace erroneous argument with constant zero. */
1170 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1171 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1173 /* If TYPE is a transparent union, pass things the way we would
1174 pass the first field of the union. We have already verified that
1175 the modes are the same. */
1176 if (TREE_CODE (type
) == UNION_TYPE
&& TYPE_TRANSPARENT_UNION (type
))
1177 type
= TREE_TYPE (TYPE_FIELDS (type
));
1179 /* Decide where to pass this arg.
1181 args[i].reg is nonzero if all or part is passed in registers.
1183 args[i].partial is nonzero if part but not all is passed in registers,
1184 and the exact value says how many words are passed in registers.
1186 args[i].pass_on_stack is nonzero if the argument must at least be
1187 computed on the stack. It may then be loaded back into registers
1188 if args[i].reg is nonzero.
1190 These decisions are driven by the FUNCTION_... macros and must agree
1191 with those made by function.c. */
1193 /* See if this argument should be passed by invisible reference. */
1194 if ((TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1195 && contains_placeholder_p (TYPE_SIZE (type
)))
1196 || TREE_ADDRESSABLE (type
)
1197 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1198 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far
, TYPE_MODE (type
),
1199 type
, argpos
< n_named_args
)
1203 /* If we're compiling a thunk, pass through invisible
1204 references instead of making a copy. */
1205 if (current_function_is_thunk
1206 #ifdef FUNCTION_ARG_CALLEE_COPIES
1207 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far
, TYPE_MODE (type
),
1208 type
, argpos
< n_named_args
)
1209 /* If it's in a register, we must make a copy of it too. */
1210 /* ??? Is this a sufficient test? Is there a better one? */
1211 && !(TREE_CODE (args
[i
].tree_value
) == VAR_DECL
1212 && REG_P (DECL_RTL (args
[i
].tree_value
)))
1213 && ! TREE_ADDRESSABLE (type
))
1217 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1218 new object from the argument. If we are passing by
1219 invisible reference, the callee will do that for us, so we
1220 can strip off the TARGET_EXPR. This is not always safe,
1221 but it is safe in the only case where this is a useful
1222 optimization; namely, when the argument is a plain object.
1223 In that case, the frontend is just asking the backend to
1224 make a bitwise copy of the argument. */
1226 if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1227 && (DECL_P (TREE_OPERAND (args
[i
].tree_value
, 1)))
1228 && ! REG_P (DECL_RTL (TREE_OPERAND (args
[i
].tree_value
, 1))))
1229 args
[i
].tree_value
= TREE_OPERAND (args
[i
].tree_value
, 1);
1231 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1232 build_pointer_type (type
),
1233 args
[i
].tree_value
);
1234 type
= build_pointer_type (type
);
1236 else if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
)
1238 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1239 We implement this by passing the address of the temporary
1240 rather than expanding it into another allocated slot. */
1241 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1242 build_pointer_type (type
),
1243 args
[i
].tree_value
);
1244 type
= build_pointer_type (type
);
1248 /* We make a copy of the object and pass the address to the
1249 function being called. */
1252 if (!COMPLETE_TYPE_P (type
)
1253 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1254 || (flag_stack_check
&& ! STACK_CHECK_BUILTIN
1255 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type
),
1256 STACK_CHECK_MAX_VAR_SIZE
))))
1258 /* This is a variable-sized object. Make space on the stack
1260 rtx size_rtx
= expr_size (TREE_VALUE (p
));
1262 if (*old_stack_level
== 0)
1264 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1265 *old_pending_adj
= pending_stack_adjust
;
1266 pending_stack_adjust
= 0;
1269 copy
= gen_rtx_MEM (BLKmode
,
1270 allocate_dynamic_stack_space
1271 (size_rtx
, NULL_RTX
, TYPE_ALIGN (type
)));
1272 set_mem_attributes (copy
, type
, 1);
1275 copy
= assign_temp (type
, 0, 1, 0);
1277 store_expr (args
[i
].tree_value
, copy
, 0);
1278 *ecf_flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
1280 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1281 build_pointer_type (type
),
1282 make_tree (type
, copy
));
1283 type
= build_pointer_type (type
);
1287 mode
= TYPE_MODE (type
);
1288 unsignedp
= TREE_UNSIGNED (type
);
1290 #ifdef PROMOTE_FUNCTION_ARGS
1291 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
1294 args
[i
].unsignedp
= unsignedp
;
1295 args
[i
].mode
= mode
;
1297 args
[i
].reg
= FUNCTION_ARG (*args_so_far
, mode
, type
,
1298 argpos
< n_named_args
);
1299 #ifdef FUNCTION_INCOMING_ARG
1300 /* If this is a sibling call and the machine has register windows, the
1301 register window has to be unwinded before calling the routine, so
1302 arguments have to go into the incoming registers. */
1303 args
[i
].tail_call_reg
= FUNCTION_INCOMING_ARG (*args_so_far
, mode
, type
,
1304 argpos
< n_named_args
);
1306 args
[i
].tail_call_reg
= args
[i
].reg
;
1309 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1312 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far
, mode
, type
,
1313 argpos
< n_named_args
);
1316 args
[i
].pass_on_stack
= MUST_PASS_IN_STACK (mode
, type
);
1318 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1319 it means that we are to pass this arg in the register(s) designated
1320 by the PARALLEL, but also to pass it in the stack. */
1321 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1322 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1323 args
[i
].pass_on_stack
= 1;
1325 /* If this is an addressable type, we must preallocate the stack
1326 since we must evaluate the object into its final location.
1328 If this is to be passed in both registers and the stack, it is simpler
1330 if (TREE_ADDRESSABLE (type
)
1331 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1332 *must_preallocate
= 1;
1334 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1335 we cannot consider this function call constant. */
1336 if (TREE_ADDRESSABLE (type
))
1337 *ecf_flags
&= ~ECF_LIBCALL_BLOCK
;
1339 /* Compute the stack-size of this argument. */
1340 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1341 || reg_parm_stack_space
> 0
1342 || args
[i
].pass_on_stack
)
1343 locate_and_pad_parm (mode
, type
,
1344 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1349 fndecl
, args_size
, &args
[i
].offset
,
1350 &args
[i
].size
, &alignment_pad
);
1352 #ifndef ARGS_GROW_DOWNWARD
1353 args
[i
].slot_offset
= *args_size
;
1356 args
[i
].alignment_pad
= alignment_pad
;
1358 /* If a part of the arg was put into registers,
1359 don't include that part in the amount pushed. */
1360 if (reg_parm_stack_space
== 0 && ! args
[i
].pass_on_stack
)
1361 args
[i
].size
.constant
-= ((args
[i
].partial
* UNITS_PER_WORD
)
1362 / (PARM_BOUNDARY
/ BITS_PER_UNIT
)
1363 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
1365 /* Update ARGS_SIZE, the total stack space for args so far. */
1367 args_size
->constant
+= args
[i
].size
.constant
;
1368 if (args
[i
].size
.var
)
1370 ADD_PARM_SIZE (*args_size
, args
[i
].size
.var
);
1373 /* Since the slot offset points to the bottom of the slot,
1374 we must record it after incrementing if the args grow down. */
1375 #ifdef ARGS_GROW_DOWNWARD
1376 args
[i
].slot_offset
= *args_size
;
1378 args
[i
].slot_offset
.constant
= -args_size
->constant
;
1380 SUB_PARM_SIZE (args
[i
].slot_offset
, args_size
->var
);
1383 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1384 have been used, etc. */
1386 FUNCTION_ARG_ADVANCE (*args_so_far
, TYPE_MODE (type
), type
,
1387 argpos
< n_named_args
);
1391 /* Update ARGS_SIZE to contain the total size for the argument block.
1392 Return the original constant component of the argument block's size.
1394 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1395 for arguments passed in registers. */
1398 compute_argument_block_size (reg_parm_stack_space
, args_size
,
1399 preferred_stack_boundary
)
1400 int reg_parm_stack_space
;
1401 struct args_size
*args_size
;
1402 int preferred_stack_boundary ATTRIBUTE_UNUSED
;
1404 int unadjusted_args_size
= args_size
->constant
;
1406 /* For accumulate outgoing args mode we don't need to align, since the frame
1407 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1408 backends from generating misaligned frame sizes. */
1409 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1410 preferred_stack_boundary
= STACK_BOUNDARY
;
1412 /* Compute the actual size of the argument block required. The variable
1413 and constant sizes must be combined, the size may have to be rounded,
1414 and there may be a minimum required size. */
1418 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1419 args_size
->constant
= 0;
1421 preferred_stack_boundary
/= BITS_PER_UNIT
;
1422 if (preferred_stack_boundary
> 1)
1424 /* We don't handle this case yet. To handle it correctly we have
1425 to add the delta, round and subtract the delta.
1426 Currently no machine description requires this support. */
1427 if (stack_pointer_delta
& (preferred_stack_boundary
- 1))
1429 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1432 if (reg_parm_stack_space
> 0)
1435 = size_binop (MAX_EXPR
, args_size
->var
,
1436 ssize_int (reg_parm_stack_space
));
1438 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1439 /* The area corresponding to register parameters is not to count in
1440 the size of the block we need. So make the adjustment. */
1442 = size_binop (MINUS_EXPR
, args_size
->var
,
1443 ssize_int (reg_parm_stack_space
));
1449 preferred_stack_boundary
/= BITS_PER_UNIT
;
1450 if (preferred_stack_boundary
< 1)
1451 preferred_stack_boundary
= 1;
1452 args_size
->constant
= (((args_size
->constant
1453 + stack_pointer_delta
1454 + preferred_stack_boundary
- 1)
1455 / preferred_stack_boundary
1456 * preferred_stack_boundary
)
1457 - stack_pointer_delta
);
1459 args_size
->constant
= MAX (args_size
->constant
,
1460 reg_parm_stack_space
);
1462 #ifdef MAYBE_REG_PARM_STACK_SPACE
1463 if (reg_parm_stack_space
== 0)
1464 args_size
->constant
= 0;
1467 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1468 args_size
->constant
-= reg_parm_stack_space
;
1471 return unadjusted_args_size
;
1474 /* Precompute parameters as needed for a function call.
1476 FLAGS is mask of ECF_* constants.
1478 NUM_ACTUALS is the number of arguments.
1480 ARGS is an array containing information for each argument; this
1481 routine fills in the INITIAL_VALUE and VALUE fields for each
1482 precomputed argument. */
1485 precompute_arguments (flags
, num_actuals
, args
)
1488 struct arg_data
*args
;
1492 /* If this function call is cse'able, precompute all the parameters.
1493 Note that if the parameter is constructed into a temporary, this will
1494 cause an additional copy because the parameter will be constructed
1495 into a temporary location and then copied into the outgoing arguments.
1496 If a parameter contains a call to alloca and this function uses the
1497 stack, precompute the parameter. */
1499 /* If we preallocated the stack space, and some arguments must be passed
1500 on the stack, then we must precompute any parameter which contains a
1501 function call which will store arguments on the stack.
1502 Otherwise, evaluating the parameter may clobber previous parameters
1503 which have already been stored into the stack. (we have code to avoid
1504 such case by saving the outgoing stack arguments, but it results in
1507 for (i
= 0; i
< num_actuals
; i
++)
1508 if ((flags
& ECF_LIBCALL_BLOCK
)
1509 || calls_function (args
[i
].tree_value
, !ACCUMULATE_OUTGOING_ARGS
))
1511 enum machine_mode mode
;
1513 /* If this is an addressable type, we cannot pre-evaluate it. */
1514 if (TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
)))
1518 = expand_expr (args
[i
].tree_value
, NULL_RTX
, VOIDmode
, 0);
1520 /* ANSI doesn't require a sequence point here,
1521 but PCC has one, so this will avoid some problems. */
1524 args
[i
].initial_value
= args
[i
].value
1525 = protect_from_queue (args
[i
].value
, 0);
1527 mode
= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
));
1528 if (mode
!= args
[i
].mode
)
1531 = convert_modes (args
[i
].mode
, mode
,
1532 args
[i
].value
, args
[i
].unsignedp
);
1533 #ifdef PROMOTE_FOR_CALL_ONLY
1534 /* CSE will replace this only if it contains args[i].value
1535 pseudo, so convert it down to the declared mode using
1537 if (GET_CODE (args
[i
].value
) == REG
1538 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
)
1540 args
[i
].initial_value
1541 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1542 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1543 SUBREG_PROMOTED_UNSIGNED_SET (args
[i
].initial_value
,
1551 /* Given the current state of MUST_PREALLOCATE and information about
1552 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1553 compute and return the final value for MUST_PREALLOCATE. */
1556 finalize_must_preallocate (must_preallocate
, num_actuals
, args
, args_size
)
1557 int must_preallocate
;
1559 struct arg_data
*args
;
1560 struct args_size
*args_size
;
1562 /* See if we have or want to preallocate stack space.
1564 If we would have to push a partially-in-regs parm
1565 before other stack parms, preallocate stack space instead.
1567 If the size of some parm is not a multiple of the required stack
1568 alignment, we must preallocate.
1570 If the total size of arguments that would otherwise create a copy in
1571 a temporary (such as a CALL) is more than half the total argument list
1572 size, preallocation is faster.
1574 Another reason to preallocate is if we have a machine (like the m88k)
1575 where stack alignment is required to be maintained between every
1576 pair of insns, not just when the call is made. However, we assume here
1577 that such machines either do not have push insns (and hence preallocation
1578 would occur anyway) or the problem is taken care of with
1581 if (! must_preallocate
)
1583 int partial_seen
= 0;
1584 int copy_to_evaluate_size
= 0;
1587 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1589 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1591 else if (partial_seen
&& args
[i
].reg
== 0)
1592 must_preallocate
= 1;
1594 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1595 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1596 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1597 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1598 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1599 copy_to_evaluate_size
1600 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1603 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1604 && args_size
->constant
> 0)
1605 must_preallocate
= 1;
1607 return must_preallocate
;
1610 /* If we preallocated stack space, compute the address of each argument
1611 and store it into the ARGS array.
1613 We need not ensure it is a valid memory address here; it will be
1614 validized when it is used.
1616 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1619 compute_argument_addresses (args
, argblock
, num_actuals
)
1620 struct arg_data
*args
;
1626 rtx arg_reg
= argblock
;
1627 int i
, arg_offset
= 0;
1629 if (GET_CODE (argblock
) == PLUS
)
1630 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1632 for (i
= 0; i
< num_actuals
; i
++)
1634 rtx offset
= ARGS_SIZE_RTX (args
[i
].offset
);
1635 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].slot_offset
);
1638 /* Skip this parm if it will not be passed on the stack. */
1639 if (! args
[i
].pass_on_stack
&& args
[i
].reg
!= 0)
1642 if (GET_CODE (offset
) == CONST_INT
)
1643 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1645 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1647 addr
= plus_constant (addr
, arg_offset
);
1648 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1649 set_mem_attributes (args
[i
].stack
,
1650 TREE_TYPE (args
[i
].tree_value
), 1);
1652 if (GET_CODE (slot_offset
) == CONST_INT
)
1653 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1655 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1657 addr
= plus_constant (addr
, arg_offset
);
1658 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1659 set_mem_attributes (args
[i
].stack_slot
,
1660 TREE_TYPE (args
[i
].tree_value
), 1);
1662 /* Function incoming arguments may overlap with sibling call
1663 outgoing arguments and we cannot allow reordering of reads
1664 from function arguments with stores to outgoing arguments
1665 of sibling calls. */
1666 set_mem_alias_set (args
[i
].stack
, 0);
1667 set_mem_alias_set (args
[i
].stack_slot
, 0);
1672 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1673 in a call instruction.
1675 FNDECL is the tree node for the target function. For an indirect call
1676 FNDECL will be NULL_TREE.
1678 EXP is the CALL_EXPR for this call. */
1681 rtx_for_function_call (fndecl
, exp
)
1687 /* Get the function to call, in the form of RTL. */
1690 /* If this is the first use of the function, see if we need to
1691 make an external definition for it. */
1692 if (! TREE_USED (fndecl
))
1694 assemble_external (fndecl
);
1695 TREE_USED (fndecl
) = 1;
1698 /* Get a SYMBOL_REF rtx for the function address. */
1699 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1702 /* Generate an rtx (probably a pseudo-register) for the address. */
1707 = expand_expr (TREE_OPERAND (exp
, 0), NULL_RTX
, VOIDmode
, 0);
1708 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1714 /* Do the register loads required for any wholly-register parms or any
1715 parms which are passed both on the stack and in a register. Their
1716 expressions were already evaluated.
1718 Mark all register-parms as living through the call, putting these USE
1719 insns in the CALL_INSN_FUNCTION_USAGE field. */
1722 load_register_parameters (args
, num_actuals
, call_fusage
, flags
)
1723 struct arg_data
*args
;
1730 #ifdef LOAD_ARGS_REVERSED
1731 for (i
= num_actuals
- 1; i
>= 0; i
--)
1733 for (i
= 0; i
< num_actuals
; i
++)
1736 rtx reg
= ((flags
& ECF_SIBCALL
)
1737 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1738 int partial
= args
[i
].partial
;
1743 /* Set to non-negative if must move a word at a time, even if just
1744 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1745 we just use a normal move insn. This value can be zero if the
1746 argument is a zero size structure with no fields. */
1747 nregs
= (partial
? partial
1748 : (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1749 ? ((int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
))
1750 + (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
)
1753 /* Handle calls that pass values in multiple non-contiguous
1754 locations. The Irix 6 ABI has examples of this. */
1756 if (GET_CODE (reg
) == PARALLEL
)
1757 emit_group_load (reg
, args
[i
].value
,
1758 int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
)));
1760 /* If simple case, just do move. If normal partial, store_one_arg
1761 has already loaded the register for us. In all other cases,
1762 load the register(s) from memory. */
1764 else if (nregs
== -1)
1765 emit_move_insn (reg
, args
[i
].value
);
1767 /* If we have pre-computed the values to put in the registers in
1768 the case of non-aligned structures, copy them in now. */
1770 else if (args
[i
].n_aligned_regs
!= 0)
1771 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1772 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1773 args
[i
].aligned_regs
[j
]);
1775 else if (partial
== 0 || args
[i
].pass_on_stack
)
1776 move_block_to_reg (REGNO (reg
),
1777 validize_mem (args
[i
].value
), nregs
,
1780 /* Handle calls that pass values in multiple non-contiguous
1781 locations. The Irix 6 ABI has examples of this. */
1782 if (GET_CODE (reg
) == PARALLEL
)
1783 use_group_regs (call_fusage
, reg
);
1784 else if (nregs
== -1)
1785 use_reg (call_fusage
, reg
);
1787 use_regs (call_fusage
, REGNO (reg
), nregs
== 0 ? 1 : nregs
);
1792 /* Try to integrate function. See expand_inline_function for documentation
1793 about the parameters. */
1796 try_to_integrate (fndecl
, actparms
, target
, ignore
, type
, structure_value_addr
)
1802 rtx structure_value_addr
;
1807 rtx old_stack_level
= 0;
1808 int reg_parm_stack_space
= 0;
1810 #ifdef REG_PARM_STACK_SPACE
1811 #ifdef MAYBE_REG_PARM_STACK_SPACE
1812 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
1814 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
1818 before_call
= get_last_insn ();
1820 timevar_push (TV_INTEGRATION
);
1822 temp
= expand_inline_function (fndecl
, actparms
, target
,
1824 structure_value_addr
);
1826 timevar_pop (TV_INTEGRATION
);
1828 /* If inlining succeeded, return. */
1829 if (temp
!= (rtx
) (size_t) - 1)
1831 if (ACCUMULATE_OUTGOING_ARGS
)
1833 /* If the outgoing argument list must be preserved, push
1834 the stack before executing the inlined function if it
1837 for (i
= reg_parm_stack_space
- 1; i
>= 0; i
--)
1838 if (i
< highest_outgoing_arg_in_use
&& stack_usage_map
[i
] != 0)
1841 if (stack_arg_under_construction
|| i
>= 0)
1844 = before_call
? NEXT_INSN (before_call
) : get_insns ();
1845 rtx insn
= NULL_RTX
, seq
;
1847 /* Look for a call in the inline function code.
1848 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1849 nonzero then there is a call and it is not necessary
1850 to scan the insns. */
1852 if (DECL_SAVED_INSNS (fndecl
)->outgoing_args_size
== 0)
1853 for (insn
= first_insn
; insn
; insn
= NEXT_INSN (insn
))
1854 if (GET_CODE (insn
) == CALL_INSN
)
1859 /* Reserve enough stack space so that the largest
1860 argument list of any function call in the inline
1861 function does not overlap the argument list being
1862 evaluated. This is usually an overestimate because
1863 allocate_dynamic_stack_space reserves space for an
1864 outgoing argument list in addition to the requested
1865 space, but there is no way to ask for stack space such
1866 that an argument list of a certain length can be
1869 Add the stack space reserved for register arguments, if
1870 any, in the inline function. What is really needed is the
1871 largest value of reg_parm_stack_space in the inline
1872 function, but that is not available. Using the current
1873 value of reg_parm_stack_space is wrong, but gives
1874 correct results on all supported machines. */
1876 int adjust
= (DECL_SAVED_INSNS (fndecl
)->outgoing_args_size
1877 + reg_parm_stack_space
);
1880 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
1881 allocate_dynamic_stack_space (GEN_INT (adjust
),
1882 NULL_RTX
, BITS_PER_UNIT
);
1885 emit_insn_before (seq
, first_insn
);
1886 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1891 /* If the result is equivalent to TARGET, return TARGET to simplify
1892 checks in store_expr. They can be equivalent but not equal in the
1893 case of a function that returns BLKmode. */
1894 if (temp
!= target
&& rtx_equal_p (temp
, target
))
1899 /* If inlining failed, mark FNDECL as needing to be compiled
1900 separately after all. If function was declared inline,
1902 if (DECL_INLINE (fndecl
) && warn_inline
&& !flag_no_inline
1903 && optimize
> 0 && !TREE_ADDRESSABLE (fndecl
))
1905 warning_with_decl (fndecl
, "inlining failed in call to `%s'");
1906 warning ("called from here");
1908 (*lang_hooks
.mark_addressable
) (fndecl
);
1909 return (rtx
) (size_t) - 1;
1912 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1913 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1914 bytes, then we would need to push some additional bytes to pad the
1915 arguments. So, we compute an adjust to the stack pointer for an
1916 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1917 bytes. Then, when the arguments are pushed the stack will be perfectly
1918 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1919 be popped after the call. Returns the adjustment. */
1922 combine_pending_stack_adjustment_and_call (unadjusted_args_size
,
1924 preferred_unit_stack_boundary
)
1925 int unadjusted_args_size
;
1926 struct args_size
*args_size
;
1927 int preferred_unit_stack_boundary
;
1929 /* The number of bytes to pop so that the stack will be
1930 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1931 HOST_WIDE_INT adjustment
;
1932 /* The alignment of the stack after the arguments are pushed, if we
1933 just pushed the arguments without adjust the stack here. */
1934 HOST_WIDE_INT unadjusted_alignment
;
1936 unadjusted_alignment
1937 = ((stack_pointer_delta
+ unadjusted_args_size
)
1938 % preferred_unit_stack_boundary
);
1940 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1941 as possible -- leaving just enough left to cancel out the
1942 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1943 PENDING_STACK_ADJUST is non-negative, and congruent to
1944 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1946 /* Begin by trying to pop all the bytes. */
1947 unadjusted_alignment
1948 = (unadjusted_alignment
1949 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1950 adjustment
= pending_stack_adjust
;
1951 /* Push enough additional bytes that the stack will be aligned
1952 after the arguments are pushed. */
1953 if (preferred_unit_stack_boundary
> 1)
1955 if (unadjusted_alignment
> 0)
1956 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1958 adjustment
+= unadjusted_alignment
;
1961 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1962 bytes after the call. The right number is the entire
1963 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1964 by the arguments in the first place. */
1966 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1971 /* Scan X expression if it does not dereference any argument slots
1972 we already clobbered by tail call arguments (as noted in stored_args_map
1974 Return nonzero if X expression dereferences such argument slots,
1978 check_sibcall_argument_overlap_1 (x
)
1989 code
= GET_CODE (x
);
1993 if (XEXP (x
, 0) == current_function_internal_arg_pointer
)
1995 else if (GET_CODE (XEXP (x
, 0)) == PLUS
1996 && XEXP (XEXP (x
, 0), 0) ==
1997 current_function_internal_arg_pointer
1998 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
)
1999 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
2003 #ifdef ARGS_GROW_DOWNWARD
2004 i
= -i
- GET_MODE_SIZE (GET_MODE (x
));
2007 for (k
= 0; k
< GET_MODE_SIZE (GET_MODE (x
)); k
++)
2008 if (i
+ k
< stored_args_map
->n_bits
2009 && TEST_BIT (stored_args_map
, i
+ k
))
2015 /* Scan all subexpressions. */
2016 fmt
= GET_RTX_FORMAT (code
);
2017 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
2021 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
2024 else if (*fmt
== 'E')
2026 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2027 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
2034 /* Scan sequence after INSN if it does not dereference any argument slots
2035 we already clobbered by tail call arguments (as noted in stored_args_map
2036 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2037 Return nonzero if sequence after INSN dereferences such argument slots,
2041 check_sibcall_argument_overlap (insn
, arg
)
2043 struct arg_data
*arg
;
2047 if (insn
== NULL_RTX
)
2048 insn
= get_insns ();
2050 insn
= NEXT_INSN (insn
);
2052 for (; insn
; insn
= NEXT_INSN (insn
))
2054 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
2057 #ifdef ARGS_GROW_DOWNWARD
2058 low
= -arg
->slot_offset
.constant
- arg
->size
.constant
;
2060 low
= arg
->slot_offset
.constant
;
2063 for (high
= low
+ arg
->size
.constant
; low
< high
; low
++)
2064 SET_BIT (stored_args_map
, low
);
2065 return insn
!= NULL_RTX
;
2068 /* Generate all the code for a function call
2069 and return an rtx for its value.
2070 Store the value in TARGET (specified as an rtx) if convenient.
2071 If the value is stored in TARGET then TARGET is returned.
2072 If IGNORE is nonzero, then we ignore the value of the function call. */
2075 expand_call (exp
, target
, ignore
)
2080 /* Nonzero if we are currently expanding a call. */
2081 static int currently_expanding_call
= 0;
2083 /* List of actual parameters. */
2084 tree actparms
= TREE_OPERAND (exp
, 1);
2085 /* RTX for the function to be called. */
2087 /* Sequence of insns to perform a tail recursive "call". */
2088 rtx tail_recursion_insns
= NULL_RTX
;
2089 /* Sequence of insns to perform a normal "call". */
2090 rtx normal_call_insns
= NULL_RTX
;
2091 /* Sequence of insns to perform a tail recursive "call". */
2092 rtx tail_call_insns
= NULL_RTX
;
2093 /* Data type of the function. */
2095 /* Declaration of the function being called,
2096 or 0 if the function is computed (not known by name). */
2099 int try_tail_call
= 1;
2100 int try_tail_recursion
= 1;
2103 /* Register in which non-BLKmode value will be returned,
2104 or 0 if no value or if value is BLKmode. */
2106 /* Address where we should return a BLKmode value;
2107 0 if value not BLKmode. */
2108 rtx structure_value_addr
= 0;
2109 /* Nonzero if that address is being passed by treating it as
2110 an extra, implicit first parameter. Otherwise,
2111 it is passed by being copied directly into struct_value_rtx. */
2112 int structure_value_addr_parm
= 0;
2113 /* Size of aggregate value wanted, or zero if none wanted
2114 or if we are using the non-reentrant PCC calling convention
2115 or expecting the value in registers. */
2116 HOST_WIDE_INT struct_value_size
= 0;
2117 /* Nonzero if called function returns an aggregate in memory PCC style,
2118 by returning the address of where to find it. */
2119 int pcc_struct_value
= 0;
2121 /* Number of actual parameters in this call, including struct value addr. */
2123 /* Number of named args. Args after this are anonymous ones
2124 and they must all go on the stack. */
2127 /* Vector of information about each argument.
2128 Arguments are numbered in the order they will be pushed,
2129 not the order they are written. */
2130 struct arg_data
*args
;
2132 /* Total size in bytes of all the stack-parms scanned so far. */
2133 struct args_size args_size
;
2134 struct args_size adjusted_args_size
;
2135 /* Size of arguments before any adjustments (such as rounding). */
2136 int unadjusted_args_size
;
2137 /* Data on reg parms scanned so far. */
2138 CUMULATIVE_ARGS args_so_far
;
2139 /* Nonzero if a reg parm has been scanned. */
2141 /* Nonzero if this is an indirect function call. */
2143 /* Nonzero if we must avoid push-insns in the args for this call.
2144 If stack space is allocated for register parameters, but not by the
2145 caller, then it is preallocated in the fixed part of the stack frame.
2146 So the entire argument block must then be preallocated (i.e., we
2147 ignore PUSH_ROUNDING in that case). */
2149 int must_preallocate
= !PUSH_ARGS
;
2151 /* Size of the stack reserved for parameter registers. */
2152 int reg_parm_stack_space
= 0;
2154 /* Address of space preallocated for stack parms
2155 (on machines that lack push insns), or 0 if space not preallocated. */
2158 /* Mask of ECF_ flags. */
2160 /* Nonzero if this is a call to an inline function. */
2161 int is_integrable
= 0;
2162 #ifdef REG_PARM_STACK_SPACE
2163 /* Define the boundary of the register parm stack space that needs to be
2165 int low_to_save
= -1, high_to_save
;
2166 rtx save_area
= 0; /* Place that it is saved */
2169 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
2170 char *initial_stack_usage_map
= stack_usage_map
;
2171 int old_stack_arg_under_construction
= 0;
2173 rtx old_stack_level
= 0;
2174 int old_pending_adj
= 0;
2175 int old_inhibit_defer_pop
= inhibit_defer_pop
;
2176 int old_stack_allocated
;
2178 tree p
= TREE_OPERAND (exp
, 0);
2180 /* The alignment of the stack, in bits. */
2181 HOST_WIDE_INT preferred_stack_boundary
;
2182 /* The alignment of the stack, in bytes. */
2183 HOST_WIDE_INT preferred_unit_stack_boundary
;
2185 /* See if this is "nothrow" function call. */
2186 if (TREE_NOTHROW (exp
))
2187 flags
|= ECF_NOTHROW
;
2189 /* See if we can find a DECL-node for the actual function.
2190 As a result, decide whether this is a call to an integrable function. */
2192 fndecl
= get_callee_fndecl (exp
);
2196 && fndecl
!= current_function_decl
2197 && DECL_INLINE (fndecl
)
2198 && DECL_SAVED_INSNS (fndecl
)
2199 && DECL_SAVED_INSNS (fndecl
)->inlinable
)
2201 else if (! TREE_ADDRESSABLE (fndecl
))
2203 /* In case this function later becomes inlinable,
2204 record that there was already a non-inline call to it.
2206 Use abstraction instead of setting TREE_ADDRESSABLE
2208 if (DECL_INLINE (fndecl
) && warn_inline
&& !flag_no_inline
2211 warning_with_decl (fndecl
, "can't inline call to `%s'");
2212 warning ("called from here");
2214 (*lang_hooks
.mark_addressable
) (fndecl
);
2217 flags
|= flags_from_decl_or_type (fndecl
);
2220 /* If we don't have specific function to call, see if we have a
2221 attributes set in the type. */
2223 flags
|= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p
)));
2225 #ifdef REG_PARM_STACK_SPACE
2226 #ifdef MAYBE_REG_PARM_STACK_SPACE
2227 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
2229 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
2233 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2234 if (reg_parm_stack_space
> 0 && PUSH_ARGS
)
2235 must_preallocate
= 1;
2238 /* Warn if this value is an aggregate type,
2239 regardless of which calling convention we are using for it. */
2240 if (warn_aggregate_return
&& AGGREGATE_TYPE_P (TREE_TYPE (exp
)))
2241 warning ("function call has aggregate value");
2243 /* Set up a place to return a structure. */
2245 /* Cater to broken compilers. */
2246 if (aggregate_value_p (exp
))
2248 /* This call returns a big structure. */
2249 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
2251 #ifdef PCC_STATIC_STRUCT_RETURN
2253 pcc_struct_value
= 1;
2254 /* Easier than making that case work right. */
2257 /* In case this is a static function, note that it has been
2259 if (! TREE_ADDRESSABLE (fndecl
))
2260 (*lang_hooks
.mark_addressable
) (fndecl
);
2264 #else /* not PCC_STATIC_STRUCT_RETURN */
2266 struct_value_size
= int_size_in_bytes (TREE_TYPE (exp
));
2268 if (target
&& GET_CODE (target
) == MEM
)
2269 structure_value_addr
= XEXP (target
, 0);
2272 /* For variable-sized objects, we must be called with a target
2273 specified. If we were to allocate space on the stack here,
2274 we would have no way of knowing when to free it. */
2275 rtx d
= assign_temp (TREE_TYPE (exp
), 1, 1, 1);
2277 mark_temp_addr_taken (d
);
2278 structure_value_addr
= XEXP (d
, 0);
2282 #endif /* not PCC_STATIC_STRUCT_RETURN */
2285 /* If called function is inline, try to integrate it. */
2289 rtx temp
= try_to_integrate (fndecl
, actparms
, target
,
2290 ignore
, TREE_TYPE (exp
),
2291 structure_value_addr
);
2292 if (temp
!= (rtx
) (size_t) - 1)
2296 /* Figure out the amount to which the stack should be aligned. */
2297 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2299 /* Operand 0 is a pointer-to-function; get the type of the function. */
2300 funtype
= TREE_TYPE (TREE_OPERAND (exp
, 0));
2301 if (! POINTER_TYPE_P (funtype
))
2303 funtype
= TREE_TYPE (funtype
);
2305 /* See if this is a call to a function that can return more than once
2306 or a call to longjmp or malloc. */
2307 flags
|= special_function_p (fndecl
, flags
);
2309 if (flags
& ECF_MAY_BE_ALLOCA
)
2310 current_function_calls_alloca
= 1;
2312 /* If struct_value_rtx is 0, it means pass the address
2313 as if it were an extra parameter. */
2314 if (structure_value_addr
&& struct_value_rtx
== 0)
2316 /* If structure_value_addr is a REG other than
2317 virtual_outgoing_args_rtx, we can use always use it. If it
2318 is not a REG, we must always copy it into a register.
2319 If it is virtual_outgoing_args_rtx, we must copy it to another
2320 register in some cases. */
2321 rtx temp
= (GET_CODE (structure_value_addr
) != REG
2322 || (ACCUMULATE_OUTGOING_ARGS
2323 && stack_arg_under_construction
2324 && structure_value_addr
== virtual_outgoing_args_rtx
)
2325 ? copy_addr_to_reg (structure_value_addr
)
2326 : structure_value_addr
);
2329 = tree_cons (error_mark_node
,
2330 make_tree (build_pointer_type (TREE_TYPE (funtype
)),
2333 structure_value_addr_parm
= 1;
2336 /* Count the arguments and set NUM_ACTUALS. */
2337 for (p
= actparms
, num_actuals
= 0; p
; p
= TREE_CHAIN (p
))
2340 /* Compute number of named args.
2341 Normally, don't include the last named arg if anonymous args follow.
2342 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2343 (If no anonymous args follow, the result of list_length is actually
2344 one too large. This is harmless.)
2346 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2347 zero, this machine will be able to place unnamed args that were
2348 passed in registers into the stack. So treat all args as named.
2349 This allows the insns emitting for a specific argument list to be
2350 independent of the function declaration.
2352 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2353 reliable way to pass unnamed args in registers, so we must force
2354 them into memory. */
2356 if ((STRICT_ARGUMENT_NAMING
2357 || ! PRETEND_OUTGOING_VARARGS_NAMED
)
2358 && TYPE_ARG_TYPES (funtype
) != 0)
2360 = (list_length (TYPE_ARG_TYPES (funtype
))
2361 /* Don't include the last named arg. */
2362 - (STRICT_ARGUMENT_NAMING
? 0 : 1)
2363 /* Count the struct value address, if it is passed as a parm. */
2364 + structure_value_addr_parm
);
2366 /* If we know nothing, treat all args as named. */
2367 n_named_args
= num_actuals
;
2369 /* Start updating where the next arg would go.
2371 On some machines (such as the PA) indirect calls have a different
2372 calling convention than normal calls. The last argument in
2373 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2375 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, (fndecl
== 0));
2377 /* Make a vector to hold all the information about each arg. */
2378 args
= (struct arg_data
*) alloca (num_actuals
* sizeof (struct arg_data
));
2379 memset ((char *) args
, 0, num_actuals
* sizeof (struct arg_data
));
2381 /* Build up entries in the ARGS array, compute the size of the
2382 arguments into ARGS_SIZE, etc. */
2383 initialize_argument_information (num_actuals
, args
, &args_size
,
2384 n_named_args
, actparms
, fndecl
,
2385 &args_so_far
, reg_parm_stack_space
,
2386 &old_stack_level
, &old_pending_adj
,
2387 &must_preallocate
, &flags
);
2391 /* If this function requires a variable-sized argument list, don't
2392 try to make a cse'able block for this call. We may be able to
2393 do this eventually, but it is too complicated to keep track of
2394 what insns go in the cse'able block and which don't. */
2396 flags
&= ~ECF_LIBCALL_BLOCK
;
2397 must_preallocate
= 1;
2400 /* Now make final decision about preallocating stack space. */
2401 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2405 /* If the structure value address will reference the stack pointer, we
2406 must stabilize it. We don't need to do this if we know that we are
2407 not going to adjust the stack pointer in processing this call. */
2409 if (structure_value_addr
2410 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2411 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2412 structure_value_addr
))
2414 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2415 structure_value_addr
= copy_to_reg (structure_value_addr
);
2417 /* Tail calls can make things harder to debug, and we're traditionally
2418 pushed these optimizations into -O2. Don't try if we're already
2419 expanding a call, as that means we're an argument. Don't try if
2420 there's cleanups, as we know there's code to follow the call.
2422 If rtx_equal_function_value_matters is false, that means we've
2423 finished with regular parsing. Which means that some of the
2424 machinery we use to generate tail-calls is no longer in place.
2425 This is most often true of sjlj-exceptions, which we couldn't
2426 tail-call to anyway. */
2428 if (currently_expanding_call
++ != 0
2429 || !flag_optimize_sibling_calls
2430 || !rtx_equal_function_value_matters
2431 || any_pending_cleanups (1)
2433 try_tail_call
= try_tail_recursion
= 0;
2435 /* Tail recursion fails, when we are not dealing with recursive calls. */
2436 if (!try_tail_recursion
2437 || TREE_CODE (TREE_OPERAND (exp
, 0)) != ADDR_EXPR
2438 || TREE_OPERAND (TREE_OPERAND (exp
, 0), 0) != current_function_decl
)
2439 try_tail_recursion
= 0;
2441 /* Rest of purposes for tail call optimizations to fail. */
2443 #ifdef HAVE_sibcall_epilogue
2444 !HAVE_sibcall_epilogue
2449 /* Doing sibling call optimization needs some work, since
2450 structure_value_addr can be allocated on the stack.
2451 It does not seem worth the effort since few optimizable
2452 sibling calls will return a structure. */
2453 || structure_value_addr
!= NULL_RTX
2454 /* If the register holding the address is a callee saved
2455 register, then we lose. We have no way to prevent that,
2456 so we only allow calls to named functions. */
2457 /* ??? This could be done by having the insn constraints
2458 use a register class that is all call-clobbered. Any
2459 reload insns generated to fix things up would appear
2460 before the sibcall_epilogue. */
2461 || fndecl
== NULL_TREE
2462 || (flags
& (ECF_RETURNS_TWICE
| ECF_LONGJMP
| ECF_NORETURN
))
2463 || !FUNCTION_OK_FOR_SIBCALL (fndecl
)
2464 /* If this function requires more stack slots than the current
2465 function, we cannot change it into a sibling call. */
2466 || args_size
.constant
> current_function_args_size
2467 /* If the callee pops its own arguments, then it must pop exactly
2468 the same number of arguments as the current function. */
2469 || RETURN_POPS_ARGS (fndecl
, funtype
, args_size
.constant
)
2470 != RETURN_POPS_ARGS (current_function_decl
,
2471 TREE_TYPE (current_function_decl
),
2472 current_function_args_size
))
2475 if (try_tail_call
|| try_tail_recursion
)
2478 actparms
= NULL_TREE
;
2479 /* Ok, we're going to give the tail call the old college try.
2480 This means we're going to evaluate the function arguments
2481 up to three times. There are two degrees of badness we can
2482 encounter, those that can be unsaved and those that can't.
2483 (See unsafe_for_reeval commentary for details.)
2485 Generate a new argument list. Pass safe arguments through
2486 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2487 For hard badness, evaluate them now and put their resulting
2488 rtx in a temporary VAR_DECL.
2490 initialize_argument_information has ordered the array for the
2491 order to be pushed, and we must remember this when reconstructing
2492 the original argument order. */
2494 if (PUSH_ARGS_REVERSED
)
2503 i
= num_actuals
- 1;
2507 for (; i
!= end
; i
+= inc
)
2509 switch (unsafe_for_reeval (args
[i
].tree_value
))
2514 case 1: /* Mildly unsafe. */
2515 args
[i
].tree_value
= unsave_expr (args
[i
].tree_value
);
2518 case 2: /* Wildly unsafe. */
2520 tree var
= build_decl (VAR_DECL
, NULL_TREE
,
2521 TREE_TYPE (args
[i
].tree_value
));
2523 expand_expr (args
[i
].tree_value
, NULL_RTX
,
2524 VOIDmode
, EXPAND_NORMAL
));
2525 args
[i
].tree_value
= var
;
2532 /* We need to build actparms for optimize_tail_recursion. We can
2533 safely trash away TREE_PURPOSE, since it is unused by this
2535 if (try_tail_recursion
)
2536 actparms
= tree_cons (NULL_TREE
, args
[i
].tree_value
, actparms
);
2538 /* Expanding one of those dangerous arguments could have added
2539 cleanups, but otherwise give it a whirl. */
2540 if (any_pending_cleanups (1))
2541 try_tail_call
= try_tail_recursion
= 0;
2544 /* Generate a tail recursion sequence when calling ourselves. */
2546 if (try_tail_recursion
)
2548 /* We want to emit any pending stack adjustments before the tail
2549 recursion "call". That way we know any adjustment after the tail
2550 recursion call can be ignored if we indeed use the tail recursion
2552 int save_pending_stack_adjust
= pending_stack_adjust
;
2553 int save_stack_pointer_delta
= stack_pointer_delta
;
2555 /* Emit any queued insns now; otherwise they would end up in
2556 only one of the alternates. */
2559 /* Use a new sequence to hold any RTL we generate. We do not even
2560 know if we will use this RTL yet. The final decision can not be
2561 made until after RTL generation for the entire function is
2564 /* If expanding any of the arguments creates cleanups, we can't
2565 do a tailcall. So, we'll need to pop the pending cleanups
2566 list. If, however, all goes well, and there are no cleanups
2567 then the call to expand_start_target_temps will have no
2569 expand_start_target_temps ();
2570 if (optimize_tail_recursion (actparms
, get_last_insn ()))
2572 if (any_pending_cleanups (1))
2573 try_tail_call
= try_tail_recursion
= 0;
2575 tail_recursion_insns
= get_insns ();
2577 expand_end_target_temps ();
2580 /* Restore the original pending stack adjustment for the sibling and
2581 normal call cases below. */
2582 pending_stack_adjust
= save_pending_stack_adjust
;
2583 stack_pointer_delta
= save_stack_pointer_delta
;
2586 if (profile_arc_flag
&& (flags
& ECF_FORK_OR_EXEC
))
2588 /* A fork duplicates the profile information, and an exec discards
2589 it. We can't rely on fork/exec to be paired. So write out the
2590 profile information we have gathered so far, and clear it. */
2591 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2592 is subject to race conditions, just as with multithreaded
2595 emit_library_call (gen_rtx_SYMBOL_REF (Pmode
, "__bb_fork_func"),
2600 /* Ensure current function's preferred stack boundary is at least
2601 what we need. We don't have to increase alignment for recursive
2603 if (cfun
->preferred_stack_boundary
< preferred_stack_boundary
2604 && fndecl
!= current_function_decl
)
2605 cfun
->preferred_stack_boundary
= preferred_stack_boundary
;
2607 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2609 function_call_count
++;
2611 /* We want to make two insn chains; one for a sibling call, the other
2612 for a normal call. We will select one of the two chains after
2613 initial RTL generation is complete. */
2614 for (pass
= 0; pass
< 2; pass
++)
2616 int sibcall_failure
= 0;
2617 /* We want to emit any pending stack adjustments before the tail
2618 recursion "call". That way we know any adjustment after the tail
2619 recursion call can be ignored if we indeed use the tail recursion
2621 int save_pending_stack_adjust
= 0;
2622 int save_stack_pointer_delta
= 0;
2624 rtx before_call
, next_arg_reg
;
2628 if (! try_tail_call
)
2631 /* Emit any queued insns now; otherwise they would end up in
2632 only one of the alternates. */
2635 /* State variables we need to save and restore between
2637 save_pending_stack_adjust
= pending_stack_adjust
;
2638 save_stack_pointer_delta
= stack_pointer_delta
;
2641 flags
&= ~ECF_SIBCALL
;
2643 flags
|= ECF_SIBCALL
;
2645 /* Other state variables that we must reinitialize each time
2646 through the loop (that are not initialized by the loop itself). */
2650 /* Start a new sequence for the normal call case.
2652 From this point on, if the sibling call fails, we want to set
2653 sibcall_failure instead of continuing the loop. */
2658 /* We know at this point that there are not currently any
2659 pending cleanups. If, however, in the process of evaluating
2660 the arguments we were to create some, we'll need to be
2661 able to get rid of them. */
2662 expand_start_target_temps ();
2665 /* Don't let pending stack adjusts add up to too much.
2666 Also, do all pending adjustments now if there is any chance
2667 this might be a call to alloca or if we are expanding a sibling
2668 call sequence or if we are calling a function that is to return
2669 with stack pointer depressed. */
2670 if (pending_stack_adjust
>= 32
2671 || (pending_stack_adjust
> 0
2672 && (flags
& (ECF_MAY_BE_ALLOCA
| ECF_SP_DEPRESSED
)))
2674 do_pending_stack_adjust ();
2676 /* When calling a const function, we must pop the stack args right away,
2677 so that the pop is deleted or moved with the call. */
2678 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
2681 #ifdef FINAL_REG_PARM_STACK_SPACE
2682 reg_parm_stack_space
= FINAL_REG_PARM_STACK_SPACE (args_size
.constant
,
2685 /* Precompute any arguments as needed. */
2687 precompute_arguments (flags
, num_actuals
, args
);
2689 /* Now we are about to start emitting insns that can be deleted
2690 if a libcall is deleted. */
2691 if (pass
&& (flags
& (ECF_LIBCALL_BLOCK
| ECF_MALLOC
)))
2694 adjusted_args_size
= args_size
;
2695 /* Compute the actual size of the argument block required. The variable
2696 and constant sizes must be combined, the size may have to be rounded,
2697 and there may be a minimum required size. When generating a sibcall
2698 pattern, do not round up, since we'll be re-using whatever space our
2700 unadjusted_args_size
2701 = compute_argument_block_size (reg_parm_stack_space
,
2702 &adjusted_args_size
,
2704 : preferred_stack_boundary
));
2706 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2708 /* The argument block when performing a sibling call is the
2709 incoming argument block. */
2712 argblock
= virtual_incoming_args_rtx
;
2714 #ifdef STACK_GROWS_DOWNWARD
2715 = plus_constant (argblock
, current_function_pretend_args_size
);
2717 = plus_constant (argblock
, -current_function_pretend_args_size
);
2719 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2720 sbitmap_zero (stored_args_map
);
2723 /* If we have no actual push instructions, or shouldn't use them,
2724 make space for all args right now. */
2725 else if (adjusted_args_size
.var
!= 0)
2727 if (old_stack_level
== 0)
2729 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
2730 old_pending_adj
= pending_stack_adjust
;
2731 pending_stack_adjust
= 0;
2732 /* stack_arg_under_construction says whether a stack arg is
2733 being constructed at the old stack level. Pushing the stack
2734 gets a clean outgoing argument block. */
2735 old_stack_arg_under_construction
= stack_arg_under_construction
;
2736 stack_arg_under_construction
= 0;
2738 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2742 /* Note that we must go through the motions of allocating an argument
2743 block even if the size is zero because we may be storing args
2744 in the area reserved for register arguments, which may be part of
2747 int needed
= adjusted_args_size
.constant
;
2749 /* Store the maximum argument space used. It will be pushed by
2750 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2753 if (needed
> current_function_outgoing_args_size
)
2754 current_function_outgoing_args_size
= needed
;
2756 if (must_preallocate
)
2758 if (ACCUMULATE_OUTGOING_ARGS
)
2760 /* Since the stack pointer will never be pushed, it is
2761 possible for the evaluation of a parm to clobber
2762 something we have already written to the stack.
2763 Since most function calls on RISC machines do not use
2764 the stack, this is uncommon, but must work correctly.
2766 Therefore, we save any area of the stack that was already
2767 written and that we are using. Here we set up to do this
2768 by making a new stack usage map from the old one. The
2769 actual save will be done by store_one_arg.
2771 Another approach might be to try to reorder the argument
2772 evaluations to avoid this conflicting stack usage. */
2774 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2775 /* Since we will be writing into the entire argument area,
2776 the map must be allocated for its entire size, not just
2777 the part that is the responsibility of the caller. */
2778 needed
+= reg_parm_stack_space
;
2781 #ifdef ARGS_GROW_DOWNWARD
2782 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2785 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2789 = (char *) alloca (highest_outgoing_arg_in_use
);
2791 if (initial_highest_arg_in_use
)
2792 memcpy (stack_usage_map
, initial_stack_usage_map
,
2793 initial_highest_arg_in_use
);
2795 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2796 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2797 (highest_outgoing_arg_in_use
2798 - initial_highest_arg_in_use
));
2801 /* The address of the outgoing argument list must not be
2802 copied to a register here, because argblock would be left
2803 pointing to the wrong place after the call to
2804 allocate_dynamic_stack_space below. */
2806 argblock
= virtual_outgoing_args_rtx
;
2810 if (inhibit_defer_pop
== 0)
2812 /* Try to reuse some or all of the pending_stack_adjust
2813 to get this space. */
2815 = (combine_pending_stack_adjustment_and_call
2816 (unadjusted_args_size
,
2817 &adjusted_args_size
,
2818 preferred_unit_stack_boundary
));
2820 /* combine_pending_stack_adjustment_and_call computes
2821 an adjustment before the arguments are allocated.
2822 Account for them and see whether or not the stack
2823 needs to go up or down. */
2824 needed
= unadjusted_args_size
- needed
;
2828 /* We're releasing stack space. */
2829 /* ??? We can avoid any adjustment at all if we're
2830 already aligned. FIXME. */
2831 pending_stack_adjust
= -needed
;
2832 do_pending_stack_adjust ();
2836 /* We need to allocate space. We'll do that in
2837 push_block below. */
2838 pending_stack_adjust
= 0;
2841 /* Special case this because overhead of `push_block' in
2842 this case is non-trivial. */
2844 argblock
= virtual_outgoing_args_rtx
;
2846 argblock
= push_block (GEN_INT (needed
), 0, 0);
2848 /* We only really need to call `copy_to_reg' in the case
2849 where push insns are going to be used to pass ARGBLOCK
2850 to a function call in ARGS. In that case, the stack
2851 pointer changes value from the allocation point to the
2852 call point, and hence the value of
2853 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2854 as well always do it. */
2855 argblock
= copy_to_reg (argblock
);
2857 /* The save/restore code in store_one_arg handles all
2858 cases except one: a constructor call (including a C
2859 function returning a BLKmode struct) to initialize
2861 if (stack_arg_under_construction
)
2863 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2864 rtx push_size
= GEN_INT (reg_parm_stack_space
2865 + adjusted_args_size
.constant
);
2867 rtx push_size
= GEN_INT (adjusted_args_size
.constant
);
2869 if (old_stack_level
== 0)
2871 emit_stack_save (SAVE_BLOCK
, &old_stack_level
,
2873 old_pending_adj
= pending_stack_adjust
;
2874 pending_stack_adjust
= 0;
2875 /* stack_arg_under_construction says whether a stack
2876 arg is being constructed at the old stack level.
2877 Pushing the stack gets a clean outgoing argument
2879 old_stack_arg_under_construction
2880 = stack_arg_under_construction
;
2881 stack_arg_under_construction
= 0;
2882 /* Make a new map for the new argument list. */
2883 stack_usage_map
= (char *)
2884 alloca (highest_outgoing_arg_in_use
);
2885 memset (stack_usage_map
, 0, highest_outgoing_arg_in_use
);
2886 highest_outgoing_arg_in_use
= 0;
2888 allocate_dynamic_stack_space (push_size
, NULL_RTX
,
2891 /* If argument evaluation might modify the stack pointer,
2892 copy the address of the argument list to a register. */
2893 for (i
= 0; i
< num_actuals
; i
++)
2894 if (args
[i
].pass_on_stack
)
2896 argblock
= copy_addr_to_reg (argblock
);
2903 compute_argument_addresses (args
, argblock
, num_actuals
);
2905 /* If we push args individually in reverse order, perform stack alignment
2906 before the first push (the last arg). */
2907 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2908 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2910 /* When the stack adjustment is pending, we get better code
2911 by combining the adjustments. */
2912 if (pending_stack_adjust
2913 && ! (flags
& ECF_LIBCALL_BLOCK
)
2914 && ! inhibit_defer_pop
)
2916 pending_stack_adjust
2917 = (combine_pending_stack_adjustment_and_call
2918 (unadjusted_args_size
,
2919 &adjusted_args_size
,
2920 preferred_unit_stack_boundary
));
2921 do_pending_stack_adjust ();
2923 else if (argblock
== 0)
2924 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2925 - unadjusted_args_size
));
2927 /* Now that the stack is properly aligned, pops can't safely
2928 be deferred during the evaluation of the arguments. */
2931 funexp
= rtx_for_function_call (fndecl
, exp
);
2933 /* Figure out the register where the value, if any, will come back. */
2935 if (TYPE_MODE (TREE_TYPE (exp
)) != VOIDmode
2936 && ! structure_value_addr
)
2938 if (pcc_struct_value
)
2939 valreg
= hard_function_value (build_pointer_type (TREE_TYPE (exp
)),
2940 fndecl
, (pass
== 0));
2942 valreg
= hard_function_value (TREE_TYPE (exp
), fndecl
, (pass
== 0));
2945 /* Precompute all register parameters. It isn't safe to compute anything
2946 once we have started filling any specific hard regs. */
2947 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2949 #ifdef REG_PARM_STACK_SPACE
2950 /* Save the fixed argument area if it's part of the caller's frame and
2951 is clobbered by argument setup for this call. */
2952 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2953 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2954 &low_to_save
, &high_to_save
);
2957 /* Now store (and compute if necessary) all non-register parms.
2958 These come before register parms, since they can require block-moves,
2959 which could clobber the registers used for register parms.
2960 Parms which have partial registers are not stored here,
2961 but we do preallocate space here if they want that. */
2963 for (i
= 0; i
< num_actuals
; i
++)
2964 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2966 rtx before_arg
= get_last_insn ();
2968 if (store_one_arg (&args
[i
], argblock
, flags
,
2969 adjusted_args_size
.var
!= 0,
2970 reg_parm_stack_space
)
2972 && check_sibcall_argument_overlap (before_arg
,
2974 sibcall_failure
= 1;
2977 /* If we have a parm that is passed in registers but not in memory
2978 and whose alignment does not permit a direct copy into registers,
2979 make a group of pseudos that correspond to each register that we
2981 if (STRICT_ALIGNMENT
)
2982 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2984 /* Now store any partially-in-registers parm.
2985 This is the last place a block-move can happen. */
2987 for (i
= 0; i
< num_actuals
; i
++)
2988 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2990 rtx before_arg
= get_last_insn ();
2992 if (store_one_arg (&args
[i
], argblock
, flags
,
2993 adjusted_args_size
.var
!= 0,
2994 reg_parm_stack_space
)
2996 && check_sibcall_argument_overlap (before_arg
,
2998 sibcall_failure
= 1;
3001 /* If we pushed args in forward order, perform stack alignment
3002 after pushing the last arg. */
3003 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
3004 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
3005 - unadjusted_args_size
));
3007 /* If register arguments require space on the stack and stack space
3008 was not preallocated, allocate stack space here for arguments
3009 passed in registers. */
3010 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3011 if (!ACCUMULATE_OUTGOING_ARGS
3012 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
3013 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
3016 /* Pass the function the address in which to return a
3018 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
3020 emit_move_insn (struct_value_rtx
,
3022 force_operand (structure_value_addr
,
3025 if (GET_CODE (struct_value_rtx
) == REG
)
3026 use_reg (&call_fusage
, struct_value_rtx
);
3029 funexp
= prepare_call_address (funexp
, fndecl
, &call_fusage
,
3030 reg_parm_seen
, pass
== 0);
3032 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
);
3034 /* Perform postincrements before actually calling the function. */
3037 /* Save a pointer to the last insn before the call, so that we can
3038 later safely search backwards to find the CALL_INSN. */
3039 before_call
= get_last_insn ();
3041 /* Set up next argument register. For sibling calls on machines
3042 with register windows this should be the incoming register. */
3043 #ifdef FUNCTION_INCOMING_ARG
3045 next_arg_reg
= FUNCTION_INCOMING_ARG (args_so_far
, VOIDmode
,
3049 next_arg_reg
= FUNCTION_ARG (args_so_far
, VOIDmode
,
3052 /* All arguments and registers used for the call must be set up by
3055 /* Stack must be properly aligned now. */
3056 if (pass
&& stack_pointer_delta
% preferred_unit_stack_boundary
)
3059 /* Generate the actual call instruction. */
3060 emit_call_1 (funexp
, fndecl
, funtype
, unadjusted_args_size
,
3061 adjusted_args_size
.constant
, struct_value_size
,
3062 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
3063 flags
, & args_so_far
);
3065 /* Verify that we've deallocated all the stack we used. */
3067 && old_stack_allocated
!= stack_pointer_delta
- pending_stack_adjust
)
3070 /* If call is cse'able, make appropriate pair of reg-notes around it.
3071 Test valreg so we don't crash; may safely ignore `const'
3072 if return type is void. Disable for PARALLEL return values, because
3073 we have no way to move such values into a pseudo register. */
3074 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
3078 if (valreg
== 0 || GET_CODE (valreg
) == PARALLEL
)
3080 insns
= get_insns ();
3087 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
3089 /* Mark the return value as a pointer if needed. */
3090 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
3091 mark_reg_pointer (temp
,
3092 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp
))));
3094 /* Construct an "equal form" for the value which mentions all the
3095 arguments in order as well as the function name. */
3096 for (i
= 0; i
< num_actuals
; i
++)
3097 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3098 args
[i
].initial_value
, note
);
3099 note
= gen_rtx_EXPR_LIST (VOIDmode
, funexp
, note
);
3101 insns
= get_insns ();
3104 if (flags
& ECF_PURE
)
3105 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3106 gen_rtx_USE (VOIDmode
,
3107 gen_rtx_MEM (BLKmode
,
3108 gen_rtx_SCRATCH (VOIDmode
))),
3111 emit_libcall_block (insns
, temp
, valreg
, note
);
3116 else if (pass
&& (flags
& ECF_MALLOC
))
3118 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
3121 /* The return value from a malloc-like function is a pointer. */
3122 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
3123 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
3125 emit_move_insn (temp
, valreg
);
3127 /* The return value from a malloc-like function can not alias
3129 last
= get_last_insn ();
3131 gen_rtx_EXPR_LIST (REG_NOALIAS
, temp
, REG_NOTES (last
));
3133 /* Write out the sequence. */
3134 insns
= get_insns ();
3140 /* For calls to `setjmp', etc., inform flow.c it should complain
3141 if nonvolatile values are live. For functions that cannot return,
3142 inform flow that control does not fall through. */
3144 if ((flags
& (ECF_NORETURN
| ECF_LONGJMP
)) || pass
== 0)
3146 /* The barrier must be emitted
3147 immediately after the CALL_INSN. Some ports emit more
3148 than just a CALL_INSN above, so we must search for it here. */
3150 rtx last
= get_last_insn ();
3151 while (GET_CODE (last
) != CALL_INSN
)
3153 last
= PREV_INSN (last
);
3154 /* There was no CALL_INSN? */
3155 if (last
== before_call
)
3159 emit_barrier_after (last
);
3162 if (flags
& ECF_LONGJMP
)
3163 current_function_calls_longjmp
= 1;
3165 /* If this function is returning into a memory location marked as
3166 readonly, it means it is initializing that location. But we normally
3167 treat functions as not clobbering such locations, so we need to
3168 specify that this one does. */
3169 if (target
!= 0 && GET_CODE (target
) == MEM
3170 && structure_value_addr
!= 0 && RTX_UNCHANGING_P (target
))
3171 emit_insn (gen_rtx_CLOBBER (VOIDmode
, target
));
3173 /* If value type not void, return an rtx for the value. */
3175 /* If there are cleanups to be called, don't use a hard reg as target.
3176 We need to double check this and see if it matters anymore. */
3177 if (any_pending_cleanups (1))
3179 if (target
&& REG_P (target
)
3180 && REGNO (target
) < FIRST_PSEUDO_REGISTER
)
3182 sibcall_failure
= 1;
3185 if (TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
3187 target
= const0_rtx
;
3188 else if (structure_value_addr
)
3190 if (target
== 0 || GET_CODE (target
) != MEM
)
3193 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
3194 memory_address (TYPE_MODE (TREE_TYPE (exp
)),
3195 structure_value_addr
));
3196 set_mem_attributes (target
, exp
, 1);
3199 else if (pcc_struct_value
)
3201 /* This is the special C++ case where we need to
3202 know what the true target was. We take care to
3203 never use this value more than once in one expression. */
3204 target
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
3205 copy_to_reg (valreg
));
3206 set_mem_attributes (target
, exp
, 1);
3208 /* Handle calls that return values in multiple non-contiguous locations.
3209 The Irix 6 ABI has examples of this. */
3210 else if (GET_CODE (valreg
) == PARALLEL
)
3214 /* This will only be assigned once, so it can be readonly. */
3215 tree nt
= build_qualified_type (TREE_TYPE (exp
),
3216 (TYPE_QUALS (TREE_TYPE (exp
))
3217 | TYPE_QUAL_CONST
));
3219 target
= assign_temp (nt
, 0, 1, 1);
3220 preserve_temp_slots (target
);
3223 if (! rtx_equal_p (target
, valreg
))
3224 emit_group_store (target
, valreg
,
3225 int_size_in_bytes (TREE_TYPE (exp
)));
3227 /* We can not support sibling calls for this case. */
3228 sibcall_failure
= 1;
3231 && GET_MODE (target
) == TYPE_MODE (TREE_TYPE (exp
))
3232 && GET_MODE (target
) == GET_MODE (valreg
))
3234 /* TARGET and VALREG cannot be equal at this point because the
3235 latter would not have REG_FUNCTION_VALUE_P true, while the
3236 former would if it were referring to the same register.
3238 If they refer to the same register, this move will be a no-op,
3239 except when function inlining is being done. */
3240 emit_move_insn (target
, valreg
);
3242 else if (TYPE_MODE (TREE_TYPE (exp
)) == BLKmode
)
3244 target
= copy_blkmode_from_reg (target
, valreg
, TREE_TYPE (exp
));
3246 /* We can not support sibling calls for this case. */
3247 sibcall_failure
= 1;
3250 target
= copy_to_reg (valreg
);
3252 #ifdef PROMOTE_FUNCTION_RETURN
3253 /* If we promoted this return value, make the proper SUBREG. TARGET
3254 might be const0_rtx here, so be careful. */
3255 if (GET_CODE (target
) == REG
3256 && TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
3257 && GET_MODE (target
) != TYPE_MODE (TREE_TYPE (exp
)))
3259 tree type
= TREE_TYPE (exp
);
3260 int unsignedp
= TREE_UNSIGNED (type
);
3263 /* If we don't promote as expected, something is wrong. */
3264 if (GET_MODE (target
)
3265 != promote_mode (type
, TYPE_MODE (type
), &unsignedp
, 1))
3268 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
3269 && GET_MODE_SIZE (GET_MODE (target
))
3270 > GET_MODE_SIZE (TYPE_MODE (type
)))
3272 offset
= GET_MODE_SIZE (GET_MODE (target
))
3273 - GET_MODE_SIZE (TYPE_MODE (type
));
3274 if (! BYTES_BIG_ENDIAN
)
3275 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
3276 else if (! WORDS_BIG_ENDIAN
)
3277 offset
%= UNITS_PER_WORD
;
3279 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
3280 SUBREG_PROMOTED_VAR_P (target
) = 1;
3281 SUBREG_PROMOTED_UNSIGNED_SET (target
, unsignedp
);
3285 /* If size of args is variable or this was a constructor call for a stack
3286 argument, restore saved stack-pointer value. */
3288 if (old_stack_level
&& ! (flags
& ECF_SP_DEPRESSED
))
3290 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
3291 pending_stack_adjust
= old_pending_adj
;
3292 stack_arg_under_construction
= old_stack_arg_under_construction
;
3293 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3294 stack_usage_map
= initial_stack_usage_map
;
3295 sibcall_failure
= 1;
3297 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
3299 #ifdef REG_PARM_STACK_SPACE
3302 restore_fixed_argument_area (save_area
, argblock
,
3303 high_to_save
, low_to_save
);
3307 /* If we saved any argument areas, restore them. */
3308 for (i
= 0; i
< num_actuals
; i
++)
3309 if (args
[i
].save_area
)
3311 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
3313 = gen_rtx_MEM (save_mode
,
3314 memory_address (save_mode
,
3315 XEXP (args
[i
].stack_slot
, 0)));
3317 if (save_mode
!= BLKmode
)
3318 emit_move_insn (stack_area
, args
[i
].save_area
);
3320 emit_block_move (stack_area
, args
[i
].save_area
,
3321 GEN_INT (args
[i
].size
.constant
),
3322 BLOCK_OP_CALL_PARM
);
3325 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3326 stack_usage_map
= initial_stack_usage_map
;
3329 /* If this was alloca, record the new stack level for nonlocal gotos.
3330 Check for the handler slots since we might not have a save area
3331 for non-local gotos. */
3333 if ((flags
& ECF_MAY_BE_ALLOCA
) && nonlocal_goto_handler_slots
!= 0)
3334 emit_stack_save (SAVE_NONLOCAL
, &nonlocal_goto_stack_level
, NULL_RTX
);
3336 /* Free up storage we no longer need. */
3337 for (i
= 0; i
< num_actuals
; ++i
)
3338 if (args
[i
].aligned_regs
)
3339 free (args
[i
].aligned_regs
);
3343 /* Undo the fake expand_start_target_temps we did earlier. If
3344 there had been any cleanups created, we've already set
3346 expand_end_target_temps ();
3349 insns
= get_insns ();
3354 tail_call_insns
= insns
;
3356 /* Restore the pending stack adjustment now that we have
3357 finished generating the sibling call sequence. */
3359 pending_stack_adjust
= save_pending_stack_adjust
;
3360 stack_pointer_delta
= save_stack_pointer_delta
;
3362 /* Prepare arg structure for next iteration. */
3363 for (i
= 0; i
< num_actuals
; i
++)
3366 args
[i
].aligned_regs
= 0;
3370 sbitmap_free (stored_args_map
);
3373 normal_call_insns
= insns
;
3375 /* If something prevents making this a sibling call,
3376 zero out the sequence. */
3377 if (sibcall_failure
)
3378 tail_call_insns
= NULL_RTX
;
3381 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3382 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3383 can happen if the arguments to this function call an inline
3384 function who's expansion contains another CALL_PLACEHOLDER.
3386 If there are any C_Ps in any of these sequences, replace them
3387 with their normal call. */
3389 for (insn
= normal_call_insns
; insn
; insn
= NEXT_INSN (insn
))
3390 if (GET_CODE (insn
) == CALL_INSN
3391 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3392 replace_call_placeholder (insn
, sibcall_use_normal
);
3394 for (insn
= tail_call_insns
; insn
; insn
= NEXT_INSN (insn
))
3395 if (GET_CODE (insn
) == CALL_INSN
3396 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3397 replace_call_placeholder (insn
, sibcall_use_normal
);
3399 for (insn
= tail_recursion_insns
; insn
; insn
= NEXT_INSN (insn
))
3400 if (GET_CODE (insn
) == CALL_INSN
3401 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3402 replace_call_placeholder (insn
, sibcall_use_normal
);
3404 /* If this was a potential tail recursion site, then emit a
3405 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3406 One of them will be selected later. */
3407 if (tail_recursion_insns
|| tail_call_insns
)
3409 /* The tail recursion label must be kept around. We could expose
3410 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3411 and makes determining true tail recursion sites difficult.
3413 So we set LABEL_PRESERVE_P here, then clear it when we select
3414 one of the call sequences after rtl generation is complete. */
3415 if (tail_recursion_insns
)
3416 LABEL_PRESERVE_P (tail_recursion_label
) = 1;
3417 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode
, normal_call_insns
,
3419 tail_recursion_insns
,
3420 tail_recursion_label
));
3423 emit_insn (normal_call_insns
);
3425 currently_expanding_call
--;
3427 /* If this function returns with the stack pointer depressed, ensure
3428 this block saves and restores the stack pointer, show it was
3429 changed, and adjust for any outgoing arg space. */
3430 if (flags
& ECF_SP_DEPRESSED
)
3432 clear_pending_stack_adjust ();
3433 emit_insn (gen_rtx (CLOBBER
, VOIDmode
, stack_pointer_rtx
));
3434 emit_move_insn (virtual_stack_dynamic_rtx
, stack_pointer_rtx
);
3435 save_stack_pointer ();
3441 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3442 The RETVAL parameter specifies whether return value needs to be saved, other
3443 parameters are documented in the emit_library_call function below. */
3446 emit_library_call_value_1 (retval
, orgfun
, value
, fn_type
, outmode
, nargs
, p
)
3450 enum libcall_type fn_type
;
3451 enum machine_mode outmode
;
3455 /* Total size in bytes of all the stack-parms scanned so far. */
3456 struct args_size args_size
;
3457 /* Size of arguments before any adjustments (such as rounding). */
3458 struct args_size original_args_size
;
3463 struct args_size alignment_pad
;
3465 CUMULATIVE_ARGS args_so_far
;
3469 enum machine_mode mode
;
3472 struct args_size offset
;
3473 struct args_size size
;
3477 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3478 rtx call_fusage
= 0;
3481 int pcc_struct_value
= 0;
3482 int struct_value_size
= 0;
3484 int reg_parm_stack_space
= 0;
3487 tree tfom
; /* type_for_mode (outmode, 0) */
3489 #ifdef REG_PARM_STACK_SPACE
3490 /* Define the boundary of the register parm stack space that needs to be
3492 int low_to_save
= -1, high_to_save
= 0;
3493 rtx save_area
= 0; /* Place that it is saved. */
3496 /* Size of the stack reserved for parameter registers. */
3497 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3498 char *initial_stack_usage_map
= stack_usage_map
;
3500 #ifdef REG_PARM_STACK_SPACE
3501 #ifdef MAYBE_REG_PARM_STACK_SPACE
3502 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
3504 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3508 /* By default, library functions can not throw. */
3509 flags
= ECF_NOTHROW
;
3521 case LCT_CONST_MAKE_BLOCK
:
3522 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
3524 case LCT_PURE_MAKE_BLOCK
:
3525 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
3528 flags
|= ECF_NORETURN
;
3531 flags
= ECF_NORETURN
;
3533 case LCT_ALWAYS_RETURN
:
3534 flags
= ECF_ALWAYS_RETURN
;
3536 case LCT_RETURNS_TWICE
:
3537 flags
= ECF_RETURNS_TWICE
;
3542 /* Ensure current function's preferred stack boundary is at least
3544 if (cfun
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3545 cfun
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3547 /* If this kind of value comes back in memory,
3548 decide where in memory it should come back. */
3549 if (outmode
!= VOIDmode
)
3551 tfom
= (*lang_hooks
.types
.type_for_mode
) (outmode
, 0);
3552 if (aggregate_value_p (tfom
))
3554 #ifdef PCC_STATIC_STRUCT_RETURN
3556 = hard_function_value (build_pointer_type (tfom
), 0, 0);
3557 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3558 pcc_struct_value
= 1;
3560 value
= gen_reg_rtx (outmode
);
3561 #else /* not PCC_STATIC_STRUCT_RETURN */
3562 struct_value_size
= GET_MODE_SIZE (outmode
);
3563 if (value
!= 0 && GET_CODE (value
) == MEM
)
3566 mem_value
= assign_temp (tfom
, 0, 1, 1);
3568 /* This call returns a big structure. */
3569 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3573 tfom
= void_type_node
;
3575 /* ??? Unfinished: must pass the memory address as an argument. */
3577 /* Copy all the libcall-arguments out of the varargs data
3578 and into a vector ARGVEC.
3580 Compute how to pass each argument. We only support a very small subset
3581 of the full argument passing conventions to limit complexity here since
3582 library functions shouldn't have many args. */
3584 argvec
= (struct arg
*) alloca ((nargs
+ 1) * sizeof (struct arg
));
3585 memset ((char *) argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3587 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3588 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3590 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0);
3593 args_size
.constant
= 0;
3598 /* Now we are about to start emitting insns that can be deleted
3599 if a libcall is deleted. */
3600 if (flags
& ECF_LIBCALL_BLOCK
)
3605 /* If there's a structure value address to be passed,
3606 either pass it in the special place, or pass it as an extra argument. */
3607 if (mem_value
&& struct_value_rtx
== 0 && ! pcc_struct_value
)
3609 rtx addr
= XEXP (mem_value
, 0);
3612 /* Make sure it is a reasonable operand for a move or push insn. */
3613 if (GET_CODE (addr
) != REG
&& GET_CODE (addr
) != MEM
3614 && ! (CONSTANT_P (addr
) && LEGITIMATE_CONSTANT_P (addr
)))
3615 addr
= force_operand (addr
, NULL_RTX
);
3617 argvec
[count
].value
= addr
;
3618 argvec
[count
].mode
= Pmode
;
3619 argvec
[count
].partial
= 0;
3621 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, Pmode
, NULL_TREE
, 1);
3622 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3623 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, Pmode
, NULL_TREE
, 1))
3627 locate_and_pad_parm (Pmode
, NULL_TREE
,
3628 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3631 argvec
[count
].reg
!= 0,
3633 NULL_TREE
, &args_size
, &argvec
[count
].offset
,
3634 &argvec
[count
].size
, &alignment_pad
);
3636 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3637 || reg_parm_stack_space
> 0)
3638 args_size
.constant
+= argvec
[count
].size
.constant
;
3640 FUNCTION_ARG_ADVANCE (args_so_far
, Pmode
, (tree
) 0, 1);
3645 for (; count
< nargs
; count
++)
3647 rtx val
= va_arg (p
, rtx
);
3648 enum machine_mode mode
= va_arg (p
, enum machine_mode
);
3650 /* We cannot convert the arg value to the mode the library wants here;
3651 must do it earlier where we know the signedness of the arg. */
3653 || (GET_MODE (val
) != mode
&& GET_MODE (val
) != VOIDmode
))
3656 /* On some machines, there's no way to pass a float to a library fcn.
3657 Pass it as a double instead. */
3658 #ifdef LIBGCC_NEEDS_DOUBLE
3659 if (LIBGCC_NEEDS_DOUBLE
&& mode
== SFmode
)
3660 val
= convert_modes (DFmode
, SFmode
, val
, 0), mode
= DFmode
;
3663 /* There's no need to call protect_from_queue, because
3664 either emit_move_insn or emit_push_insn will do that. */
3666 /* Make sure it is a reasonable operand for a move or push insn. */
3667 if (GET_CODE (val
) != REG
&& GET_CODE (val
) != MEM
3668 && ! (CONSTANT_P (val
) && LEGITIMATE_CONSTANT_P (val
)))
3669 val
= force_operand (val
, NULL_RTX
);
3671 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3672 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far
, mode
, NULL_TREE
, 1))
3676 #ifdef FUNCTION_ARG_CALLEE_COPIES
3677 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far
, mode
,
3682 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3683 functions, so we have to pretend this isn't such a function. */
3684 if (flags
& ECF_LIBCALL_BLOCK
)
3686 rtx insns
= get_insns ();
3690 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3692 /* If this was a CONST function, it is now PURE since
3693 it now reads memory. */
3694 if (flags
& ECF_CONST
)
3696 flags
&= ~ECF_CONST
;
3700 if (GET_MODE (val
) == MEM
&& ! must_copy
)
3704 slot
= assign_temp ((*lang_hooks
.types
.type_for_mode
) (mode
, 0),
3706 emit_move_insn (slot
, val
);
3710 tree type
= (*lang_hooks
.types
.type_for_mode
) (mode
, 0);
3712 slot
= gen_rtx_MEM (mode
,
3713 expand_expr (build1 (ADDR_EXPR
,
3716 make_tree (type
, val
)),
3717 NULL_RTX
, VOIDmode
, 0));
3720 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3721 gen_rtx_USE (VOIDmode
, slot
),
3724 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3725 gen_rtx_CLOBBER (VOIDmode
,
3730 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3734 argvec
[count
].value
= val
;
3735 argvec
[count
].mode
= mode
;
3737 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, mode
, NULL_TREE
, 1);
3739 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3740 argvec
[count
].partial
3741 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, mode
, NULL_TREE
, 1);
3743 argvec
[count
].partial
= 0;
3746 locate_and_pad_parm (mode
, NULL_TREE
,
3747 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3750 argvec
[count
].reg
!= 0,
3752 NULL_TREE
, &args_size
, &argvec
[count
].offset
,
3753 &argvec
[count
].size
, &alignment_pad
);
3755 if (argvec
[count
].size
.var
)
3758 if (reg_parm_stack_space
== 0 && argvec
[count
].partial
)
3759 argvec
[count
].size
.constant
-= argvec
[count
].partial
* UNITS_PER_WORD
;
3761 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3762 || reg_parm_stack_space
> 0)
3763 args_size
.constant
+= argvec
[count
].size
.constant
;
3765 FUNCTION_ARG_ADVANCE (args_so_far
, mode
, (tree
) 0, 1);
3768 #ifdef FINAL_REG_PARM_STACK_SPACE
3769 reg_parm_stack_space
= FINAL_REG_PARM_STACK_SPACE (args_size
.constant
,
3772 /* If this machine requires an external definition for library
3773 functions, write one out. */
3774 assemble_external_libcall (fun
);
3776 original_args_size
= args_size
;
3777 args_size
.constant
= (((args_size
.constant
3778 + stack_pointer_delta
3782 - stack_pointer_delta
);
3784 args_size
.constant
= MAX (args_size
.constant
,
3785 reg_parm_stack_space
);
3787 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3788 args_size
.constant
-= reg_parm_stack_space
;
3791 if (args_size
.constant
> current_function_outgoing_args_size
)
3792 current_function_outgoing_args_size
= args_size
.constant
;
3794 if (ACCUMULATE_OUTGOING_ARGS
)
3796 /* Since the stack pointer will never be pushed, it is possible for
3797 the evaluation of a parm to clobber something we have already
3798 written to the stack. Since most function calls on RISC machines
3799 do not use the stack, this is uncommon, but must work correctly.
3801 Therefore, we save any area of the stack that was already written
3802 and that we are using. Here we set up to do this by making a new
3803 stack usage map from the old one.
3805 Another approach might be to try to reorder the argument
3806 evaluations to avoid this conflicting stack usage. */
3808 needed
= args_size
.constant
;
3810 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3811 /* Since we will be writing into the entire argument area, the
3812 map must be allocated for its entire size, not just the part that
3813 is the responsibility of the caller. */
3814 needed
+= reg_parm_stack_space
;
3817 #ifdef ARGS_GROW_DOWNWARD
3818 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3821 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3824 stack_usage_map
= (char *) alloca (highest_outgoing_arg_in_use
);
3826 if (initial_highest_arg_in_use
)
3827 memcpy (stack_usage_map
, initial_stack_usage_map
,
3828 initial_highest_arg_in_use
);
3830 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3831 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3832 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3835 /* We must be careful to use virtual regs before they're instantiated,
3836 and real regs afterwards. Loop optimization, for example, can create
3837 new libcalls after we've instantiated the virtual regs, and if we
3838 use virtuals anyway, they won't match the rtl patterns. */
3840 if (virtuals_instantiated
)
3841 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3843 argblock
= virtual_outgoing_args_rtx
;
3848 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3851 /* If we push args individually in reverse order, perform stack alignment
3852 before the first push (the last arg). */
3853 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3854 anti_adjust_stack (GEN_INT (args_size
.constant
3855 - original_args_size
.constant
));
3857 if (PUSH_ARGS_REVERSED
)
3868 #ifdef REG_PARM_STACK_SPACE
3869 if (ACCUMULATE_OUTGOING_ARGS
)
3871 /* The argument list is the property of the called routine and it
3872 may clobber it. If the fixed area has been used for previous
3873 parameters, we must save and restore it.
3875 Here we compute the boundary of the that needs to be saved, if any. */
3877 #ifdef ARGS_GROW_DOWNWARD
3878 for (count
= 0; count
< reg_parm_stack_space
+ 1; count
++)
3880 for (count
= 0; count
< reg_parm_stack_space
; count
++)
3883 if (count
>= highest_outgoing_arg_in_use
3884 || stack_usage_map
[count
] == 0)
3887 if (low_to_save
== -1)
3888 low_to_save
= count
;
3890 high_to_save
= count
;
3893 if (low_to_save
>= 0)
3895 int num_to_save
= high_to_save
- low_to_save
+ 1;
3896 enum machine_mode save_mode
3897 = mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
3900 /* If we don't have the required alignment, must do this in BLKmode. */
3901 if ((low_to_save
& (MIN (GET_MODE_SIZE (save_mode
),
3902 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
3903 save_mode
= BLKmode
;
3905 #ifdef ARGS_GROW_DOWNWARD
3906 stack_area
= gen_rtx_MEM (save_mode
,
3907 memory_address (save_mode
,
3908 plus_constant (argblock
,
3911 stack_area
= gen_rtx_MEM (save_mode
,
3912 memory_address (save_mode
,
3913 plus_constant (argblock
,
3916 if (save_mode
== BLKmode
)
3918 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
3919 set_mem_align (save_area
, PARM_BOUNDARY
);
3920 emit_block_move (save_area
, stack_area
, GEN_INT (num_to_save
),
3921 BLOCK_OP_CALL_PARM
);
3925 save_area
= gen_reg_rtx (save_mode
);
3926 emit_move_insn (save_area
, stack_area
);
3932 /* Push the args that need to be pushed. */
3934 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3935 are to be pushed. */
3936 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3938 enum machine_mode mode
= argvec
[argnum
].mode
;
3939 rtx val
= argvec
[argnum
].value
;
3940 rtx reg
= argvec
[argnum
].reg
;
3941 int partial
= argvec
[argnum
].partial
;
3942 int lower_bound
= 0, upper_bound
= 0, i
;
3944 if (! (reg
!= 0 && partial
== 0))
3946 if (ACCUMULATE_OUTGOING_ARGS
)
3948 /* If this is being stored into a pre-allocated, fixed-size,
3949 stack area, save any previous data at that location. */
3951 #ifdef ARGS_GROW_DOWNWARD
3952 /* stack_slot is negative, but we want to index stack_usage_map
3953 with positive values. */
3954 upper_bound
= -argvec
[argnum
].offset
.constant
+ 1;
3955 lower_bound
= upper_bound
- argvec
[argnum
].size
.constant
;
3957 lower_bound
= argvec
[argnum
].offset
.constant
;
3958 upper_bound
= lower_bound
+ argvec
[argnum
].size
.constant
;
3961 for (i
= lower_bound
; i
< upper_bound
; i
++)
3962 if (stack_usage_map
[i
]
3963 /* Don't store things in the fixed argument area at this
3964 point; it has already been saved. */
3965 && i
> reg_parm_stack_space
)
3968 if (i
!= upper_bound
)
3970 /* We need to make a save area. See what mode we can make
3972 enum machine_mode save_mode
3973 = mode_for_size (argvec
[argnum
].size
.constant
3981 plus_constant (argblock
,
3982 argvec
[argnum
].offset
.constant
)));
3983 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3985 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3989 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, PARM_BOUNDARY
,
3990 partial
, reg
, 0, argblock
,
3991 GEN_INT (argvec
[argnum
].offset
.constant
),
3992 reg_parm_stack_space
, ARGS_SIZE_RTX (alignment_pad
));
3994 /* Now mark the segment we just used. */
3995 if (ACCUMULATE_OUTGOING_ARGS
)
3996 for (i
= lower_bound
; i
< upper_bound
; i
++)
3997 stack_usage_map
[i
] = 1;
4003 /* If we pushed args in forward order, perform stack alignment
4004 after pushing the last arg. */
4005 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
4006 anti_adjust_stack (GEN_INT (args_size
.constant
4007 - original_args_size
.constant
));
4009 if (PUSH_ARGS_REVERSED
)
4014 fun
= prepare_call_address (fun
, NULL_TREE
, &call_fusage
, 0, 0);
4016 /* Now load any reg parms into their regs. */
4018 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4019 are to be pushed. */
4020 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
4022 rtx val
= argvec
[argnum
].value
;
4023 rtx reg
= argvec
[argnum
].reg
;
4024 int partial
= argvec
[argnum
].partial
;
4026 /* Handle calls that pass values in multiple non-contiguous
4027 locations. The PA64 has examples of this for library calls. */
4028 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
4029 emit_group_load (reg
, val
, GET_MODE_SIZE (GET_MODE (val
)));
4030 else if (reg
!= 0 && partial
== 0)
4031 emit_move_insn (reg
, val
);
4036 /* Any regs containing parms remain in use through the call. */
4037 for (count
= 0; count
< nargs
; count
++)
4039 rtx reg
= argvec
[count
].reg
;
4040 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
4041 use_group_regs (&call_fusage
, reg
);
4043 use_reg (&call_fusage
, reg
);
4046 /* Pass the function the address in which to return a structure value. */
4047 if (mem_value
!= 0 && struct_value_rtx
!= 0 && ! pcc_struct_value
)
4049 emit_move_insn (struct_value_rtx
,
4051 force_operand (XEXP (mem_value
, 0),
4053 if (GET_CODE (struct_value_rtx
) == REG
)
4054 use_reg (&call_fusage
, struct_value_rtx
);
4057 /* Don't allow popping to be deferred, since then
4058 cse'ing of library calls could delete a call and leave the pop. */
4060 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
4061 ? hard_libcall_value (outmode
) : NULL_RTX
);
4063 /* Stack must be properly aligned now. */
4064 if (stack_pointer_delta
& (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1))
4067 before_call
= get_last_insn ();
4069 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4070 will set inhibit_defer_pop to that value. */
4071 /* The return type is needed to decide how many bytes the function pops.
4072 Signedness plays no role in that, so for simplicity, we pretend it's
4073 always signed. We also assume that the list of arguments passed has
4074 no impact, so we pretend it is unknown. */
4077 get_identifier (XSTR (orgfun
, 0)),
4078 build_function_type (tfom
, NULL_TREE
),
4079 original_args_size
.constant
, args_size
.constant
,
4081 FUNCTION_ARG (args_so_far
, VOIDmode
, void_type_node
, 1),
4083 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, & args_so_far
);
4085 /* For calls to `setjmp', etc., inform flow.c it should complain
4086 if nonvolatile values are live. For functions that cannot return,
4087 inform flow that control does not fall through. */
4089 if (flags
& (ECF_NORETURN
| ECF_LONGJMP
))
4091 /* The barrier note must be emitted
4092 immediately after the CALL_INSN. Some ports emit more than
4093 just a CALL_INSN above, so we must search for it here. */
4095 rtx last
= get_last_insn ();
4096 while (GET_CODE (last
) != CALL_INSN
)
4098 last
= PREV_INSN (last
);
4099 /* There was no CALL_INSN? */
4100 if (last
== before_call
)
4104 emit_barrier_after (last
);
4107 /* Now restore inhibit_defer_pop to its actual original value. */
4110 /* If call is cse'able, make appropriate pair of reg-notes around it.
4111 Test valreg so we don't crash; may safely ignore `const'
4112 if return type is void. Disable for PARALLEL return values, because
4113 we have no way to move such values into a pseudo register. */
4114 if (flags
& ECF_LIBCALL_BLOCK
)
4118 if (valreg
== 0 || GET_CODE (valreg
) == PARALLEL
)
4120 insns
= get_insns ();
4127 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
4130 /* Construct an "equal form" for the value which mentions all the
4131 arguments in order as well as the function name. */
4132 for (i
= 0; i
< nargs
; i
++)
4133 note
= gen_rtx_EXPR_LIST (VOIDmode
, argvec
[i
].value
, note
);
4134 note
= gen_rtx_EXPR_LIST (VOIDmode
, fun
, note
);
4136 insns
= get_insns ();
4139 if (flags
& ECF_PURE
)
4140 note
= gen_rtx_EXPR_LIST (VOIDmode
,
4141 gen_rtx_USE (VOIDmode
,
4142 gen_rtx_MEM (BLKmode
,
4143 gen_rtx_SCRATCH (VOIDmode
))),
4146 emit_libcall_block (insns
, temp
, valreg
, note
);
4153 /* Copy the value to the right place. */
4154 if (outmode
!= VOIDmode
&& retval
)
4160 if (value
!= mem_value
)
4161 emit_move_insn (value
, mem_value
);
4163 else if (value
!= 0)
4164 emit_move_insn (value
, valreg
);
4169 if (ACCUMULATE_OUTGOING_ARGS
)
4171 #ifdef REG_PARM_STACK_SPACE
4174 enum machine_mode save_mode
= GET_MODE (save_area
);
4175 #ifdef ARGS_GROW_DOWNWARD
4177 = gen_rtx_MEM (save_mode
,
4178 memory_address (save_mode
,
4179 plus_constant (argblock
,
4183 = gen_rtx_MEM (save_mode
,
4184 memory_address (save_mode
,
4185 plus_constant (argblock
, low_to_save
)));
4188 set_mem_align (stack_area
, PARM_BOUNDARY
);
4189 if (save_mode
!= BLKmode
)
4190 emit_move_insn (stack_area
, save_area
);
4192 emit_block_move (stack_area
, save_area
,
4193 GEN_INT (high_to_save
- low_to_save
+ 1),
4194 BLOCK_OP_CALL_PARM
);
4198 /* If we saved any argument areas, restore them. */
4199 for (count
= 0; count
< nargs
; count
++)
4200 if (argvec
[count
].save_area
)
4202 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
4204 = gen_rtx_MEM (save_mode
,
4207 plus_constant (argblock
,
4208 argvec
[count
].offset
.constant
)));
4210 emit_move_insn (stack_area
, argvec
[count
].save_area
);
4213 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4214 stack_usage_map
= initial_stack_usage_map
;
4221 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4222 (emitting the queue unless NO_QUEUE is nonzero),
4223 for a value of mode OUTMODE,
4224 with NARGS different arguments, passed as alternating rtx values
4225 and machine_modes to convert them to.
4226 The rtx values should have been passed through protect_from_queue already.
4228 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4229 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4230 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4231 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4232 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4233 or other LCT_ value for other types of library calls. */
4236 emit_library_call
VPARAMS((rtx orgfun
, enum libcall_type fn_type
,
4237 enum machine_mode outmode
, int nargs
, ...))
4240 VA_FIXEDARG (p
, rtx
, orgfun
);
4241 VA_FIXEDARG (p
, int, fn_type
);
4242 VA_FIXEDARG (p
, enum machine_mode
, outmode
);
4243 VA_FIXEDARG (p
, int, nargs
);
4245 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
4250 /* Like emit_library_call except that an extra argument, VALUE,
4251 comes second and says where to store the result.
4252 (If VALUE is zero, this function chooses a convenient way
4253 to return the value.
4255 This function returns an rtx for where the value is to be found.
4256 If VALUE is nonzero, VALUE is returned. */
4259 emit_library_call_value
VPARAMS((rtx orgfun
, rtx value
,
4260 enum libcall_type fn_type
,
4261 enum machine_mode outmode
, int nargs
, ...))
4266 VA_FIXEDARG (p
, rtx
, orgfun
);
4267 VA_FIXEDARG (p
, rtx
, value
);
4268 VA_FIXEDARG (p
, int, fn_type
);
4269 VA_FIXEDARG (p
, enum machine_mode
, outmode
);
4270 VA_FIXEDARG (p
, int, nargs
);
4272 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
4280 /* Store a single argument for a function call
4281 into the register or memory area where it must be passed.
4282 *ARG describes the argument value and where to pass it.
4284 ARGBLOCK is the address of the stack-block for all the arguments,
4285 or 0 on a machine where arguments are pushed individually.
4287 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4288 so must be careful about how the stack is used.
4290 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4291 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4292 that we need not worry about saving and restoring the stack.
4294 FNDECL is the declaration of the function we are calling.
4296 Return nonzero if this arg should cause sibcall failure,
4300 store_one_arg (arg
, argblock
, flags
, variable_size
, reg_parm_stack_space
)
4301 struct arg_data
*arg
;
4304 int variable_size ATTRIBUTE_UNUSED
;
4305 int reg_parm_stack_space
;
4307 tree pval
= arg
->tree_value
;
4311 int i
, lower_bound
= 0, upper_bound
= 0;
4312 int sibcall_failure
= 0;
4314 if (TREE_CODE (pval
) == ERROR_MARK
)
4317 /* Push a new temporary level for any temporaries we make for
4321 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4323 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4324 save any previous data at that location. */
4325 if (argblock
&& ! variable_size
&& arg
->stack
)
4327 #ifdef ARGS_GROW_DOWNWARD
4328 /* stack_slot is negative, but we want to index stack_usage_map
4329 with positive values. */
4330 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4331 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4335 lower_bound
= upper_bound
- arg
->size
.constant
;
4337 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4338 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4342 upper_bound
= lower_bound
+ arg
->size
.constant
;
4345 for (i
= lower_bound
; i
< upper_bound
; i
++)
4346 if (stack_usage_map
[i
]
4347 /* Don't store things in the fixed argument area at this point;
4348 it has already been saved. */
4349 && i
> reg_parm_stack_space
)
4352 if (i
!= upper_bound
)
4354 /* We need to make a save area. See what mode we can make it. */
4355 enum machine_mode save_mode
4356 = mode_for_size (arg
->size
.constant
* BITS_PER_UNIT
, MODE_INT
, 1);
4358 = gen_rtx_MEM (save_mode
,
4359 memory_address (save_mode
,
4360 XEXP (arg
->stack_slot
, 0)));
4362 if (save_mode
== BLKmode
)
4364 tree ot
= TREE_TYPE (arg
->tree_value
);
4365 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4366 | TYPE_QUAL_CONST
));
4368 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4369 preserve_temp_slots (arg
->save_area
);
4370 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4371 expr_size (arg
->tree_value
),
4372 BLOCK_OP_CALL_PARM
);
4376 arg
->save_area
= gen_reg_rtx (save_mode
);
4377 emit_move_insn (arg
->save_area
, stack_area
);
4381 /* Now that we have saved any slots that will be overwritten by this
4382 store, mark all slots this store will use. We must do this before
4383 we actually expand the argument since the expansion itself may
4384 trigger library calls which might need to use the same stack slot. */
4385 if (argblock
&& ! variable_size
&& arg
->stack
)
4386 for (i
= lower_bound
; i
< upper_bound
; i
++)
4387 stack_usage_map
[i
] = 1;
4390 /* If this isn't going to be placed on both the stack and in registers,
4391 set up the register and number of words. */
4392 if (! arg
->pass_on_stack
)
4394 if (flags
& ECF_SIBCALL
)
4395 reg
= arg
->tail_call_reg
;
4398 partial
= arg
->partial
;
4401 if (reg
!= 0 && partial
== 0)
4402 /* Being passed entirely in a register. We shouldn't be called in
4406 /* If this arg needs special alignment, don't load the registers
4408 if (arg
->n_aligned_regs
!= 0)
4411 /* If this is being passed partially in a register, we can't evaluate
4412 it directly into its stack slot. Otherwise, we can. */
4413 if (arg
->value
== 0)
4415 /* stack_arg_under_construction is nonzero if a function argument is
4416 being evaluated directly into the outgoing argument list and
4417 expand_call must take special action to preserve the argument list
4418 if it is called recursively.
4420 For scalar function arguments stack_usage_map is sufficient to
4421 determine which stack slots must be saved and restored. Scalar
4422 arguments in general have pass_on_stack == 0.
4424 If this argument is initialized by a function which takes the
4425 address of the argument (a C++ constructor or a C function
4426 returning a BLKmode structure), then stack_usage_map is
4427 insufficient and expand_call must push the stack around the
4428 function call. Such arguments have pass_on_stack == 1.
4430 Note that it is always safe to set stack_arg_under_construction,
4431 but this generates suboptimal code if set when not needed. */
4433 if (arg
->pass_on_stack
)
4434 stack_arg_under_construction
++;
4436 arg
->value
= expand_expr (pval
,
4438 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4439 ? NULL_RTX
: arg
->stack
,
4442 /* If we are promoting object (or for any other reason) the mode
4443 doesn't agree, convert the mode. */
4445 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4446 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4447 arg
->value
, arg
->unsignedp
);
4449 if (arg
->pass_on_stack
)
4450 stack_arg_under_construction
--;
4453 /* Don't allow anything left on stack from computation
4454 of argument to alloca. */
4455 if (flags
& ECF_MAY_BE_ALLOCA
)
4456 do_pending_stack_adjust ();
4458 if (arg
->value
== arg
->stack
)
4459 /* If the value is already in the stack slot, we are done. */
4461 else if (arg
->mode
!= BLKmode
)
4465 /* Argument is a scalar, not entirely passed in registers.
4466 (If part is passed in registers, arg->partial says how much
4467 and emit_push_insn will take care of putting it there.)
4469 Push it, and if its size is less than the
4470 amount of space allocated to it,
4471 also bump stack pointer by the additional space.
4472 Note that in C the default argument promotions
4473 will prevent such mismatches. */
4475 size
= GET_MODE_SIZE (arg
->mode
);
4476 /* Compute how much space the push instruction will push.
4477 On many machines, pushing a byte will advance the stack
4478 pointer by a halfword. */
4479 #ifdef PUSH_ROUNDING
4480 size
= PUSH_ROUNDING (size
);
4484 /* Compute how much space the argument should get:
4485 round up to a multiple of the alignment for arguments. */
4486 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4487 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4488 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4489 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4491 /* This isn't already where we want it on the stack, so put it there.
4492 This can either be done with push or copy insns. */
4493 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
,
4494 PARM_BOUNDARY
, partial
, reg
, used
- size
, argblock
,
4495 ARGS_SIZE_RTX (arg
->offset
), reg_parm_stack_space
,
4496 ARGS_SIZE_RTX (arg
->alignment_pad
));
4498 /* Unless this is a partially-in-register argument, the argument is now
4501 arg
->value
= arg
->stack
;
4505 /* BLKmode, at least partly to be pushed. */
4507 unsigned int parm_align
;
4511 /* Pushing a nonscalar.
4512 If part is passed in registers, PARTIAL says how much
4513 and emit_push_insn will take care of putting it there. */
4515 /* Round its size up to a multiple
4516 of the allocation unit for arguments. */
4518 if (arg
->size
.var
!= 0)
4521 size_rtx
= ARGS_SIZE_RTX (arg
->size
);
4525 /* PUSH_ROUNDING has no effect on us, because
4526 emit_push_insn for BLKmode is careful to avoid it. */
4527 excess
= (arg
->size
.constant
- int_size_in_bytes (TREE_TYPE (pval
))
4528 + partial
* UNITS_PER_WORD
);
4529 size_rtx
= expand_expr (size_in_bytes (TREE_TYPE (pval
)),
4530 NULL_RTX
, TYPE_MODE (sizetype
), 0);
4533 /* Some types will require stricter alignment, which will be
4534 provided for elsewhere in argument layout. */
4535 parm_align
= MAX (PARM_BOUNDARY
, TYPE_ALIGN (TREE_TYPE (pval
)));
4537 /* When an argument is padded down, the block is aligned to
4538 PARM_BOUNDARY, but the actual argument isn't. */
4539 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4542 parm_align
= BITS_PER_UNIT
;
4545 unsigned int excess_align
= (excess
& -excess
) * BITS_PER_UNIT
;
4546 parm_align
= MIN (parm_align
, excess_align
);
4550 if ((flags
& ECF_SIBCALL
) && GET_CODE (arg
->value
) == MEM
)
4552 /* emit_push_insn might not work properly if arg->value and
4553 argblock + arg->offset areas overlap. */
4557 if (XEXP (x
, 0) == current_function_internal_arg_pointer
4558 || (GET_CODE (XEXP (x
, 0)) == PLUS
4559 && XEXP (XEXP (x
, 0), 0) ==
4560 current_function_internal_arg_pointer
4561 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
))
4563 if (XEXP (x
, 0) != current_function_internal_arg_pointer
)
4564 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4566 /* expand_call should ensure this */
4567 if (arg
->offset
.var
|| GET_CODE (size_rtx
) != CONST_INT
)
4570 if (arg
->offset
.constant
> i
)
4572 if (arg
->offset
.constant
< i
+ INTVAL (size_rtx
))
4573 sibcall_failure
= 1;
4575 else if (arg
->offset
.constant
< i
)
4577 if (i
< arg
->offset
.constant
+ INTVAL (size_rtx
))
4578 sibcall_failure
= 1;
4583 /* Special handling is required if part of the parameter lies in the
4584 register parameter area. The argument may be copied into the stack
4585 slot using memcpy(), but the original contents of the register
4586 parameter area will be restored after the memcpy() call.
4588 To ensure that the part that lies in the register parameter area
4589 is copied correctly, we emit a separate push for that part. This
4590 push should be small enough to avoid a call to memcpy(). */
4591 #ifndef STACK_PARMS_IN_REG_PARM_AREA
4592 if (arg
->reg
&& arg
->pass_on_stack
)
4597 if (arg
->offset
.constant
< reg_parm_stack_space
&& arg
->offset
.var
)
4598 error ("variable offset is passed partially in stack and in reg");
4599 else if (arg
->offset
.constant
< reg_parm_stack_space
&& arg
->size
.var
)
4600 error ("variable size is passed partially in stack and in reg");
4601 else if (arg
->offset
.constant
< reg_parm_stack_space
4602 && ((arg
->offset
.constant
+ arg
->size
.constant
)
4603 > reg_parm_stack_space
))
4605 rtx size_rtx1
= GEN_INT (reg_parm_stack_space
- arg
->offset
.constant
);
4606 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx1
,
4607 parm_align
, partial
, reg
, excess
, argblock
,
4608 ARGS_SIZE_RTX (arg
->offset
), reg_parm_stack_space
,
4609 ARGS_SIZE_RTX (arg
->alignment_pad
));
4614 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4615 parm_align
, partial
, reg
, excess
, argblock
,
4616 ARGS_SIZE_RTX (arg
->offset
), reg_parm_stack_space
,
4617 ARGS_SIZE_RTX (arg
->alignment_pad
));
4619 /* Unless this is a partially-in-register argument, the argument is now
4622 ??? Unlike the case above, in which we want the actual
4623 address of the data, so that we can load it directly into a
4624 register, here we want the address of the stack slot, so that
4625 it's properly aligned for word-by-word copying or something
4626 like that. It's not clear that this is always correct. */
4628 arg
->value
= arg
->stack_slot
;
4631 /* Once we have pushed something, pops can't safely
4632 be deferred during the rest of the arguments. */
4635 /* ANSI doesn't require a sequence point here,
4636 but PCC has one, so this will avoid some problems. */
4639 /* Free any temporary slots made in processing this argument. Show
4640 that we might have taken the address of something and pushed that
4642 preserve_temp_slots (NULL_RTX
);
4646 return sibcall_failure
;