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 /* Non-zero 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 non-zero 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 we are to promote the function arg to a wider mode,
882 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
884 = convert_modes (args
[i
].mode
,
885 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
886 args
[i
].value
, args
[i
].unsignedp
);
888 /* If the value is expensive, and we are inside an appropriately
889 short loop, put the value into a pseudo and then put the pseudo
892 For small register classes, also do this if this call uses
893 register parameters. This is to avoid reload conflicts while
894 loading the parameters registers. */
896 if ((! (GET_CODE (args
[i
].value
) == REG
897 || (GET_CODE (args
[i
].value
) == SUBREG
898 && GET_CODE (SUBREG_REG (args
[i
].value
)) == REG
)))
899 && args
[i
].mode
!= BLKmode
900 && rtx_cost (args
[i
].value
, SET
) > COSTS_N_INSNS (1)
901 && ((SMALL_REGISTER_CLASSES
&& *reg_parm_seen
)
902 || preserve_subexpressions_p ()))
903 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
907 #ifdef REG_PARM_STACK_SPACE
909 /* The argument list is the property of the called routine and it
910 may clobber it. If the fixed area has been used for previous
911 parameters, we must save and restore it. */
914 save_fixed_argument_area (reg_parm_stack_space
, argblock
,
915 low_to_save
, high_to_save
)
916 int reg_parm_stack_space
;
922 rtx save_area
= NULL_RTX
;
924 /* Compute the boundary of the that needs to be saved, if any. */
925 #ifdef ARGS_GROW_DOWNWARD
926 for (i
= 0; i
< reg_parm_stack_space
+ 1; i
++)
928 for (i
= 0; i
< reg_parm_stack_space
; i
++)
931 if (i
>= highest_outgoing_arg_in_use
932 || stack_usage_map
[i
] == 0)
935 if (*low_to_save
== -1)
941 if (*low_to_save
>= 0)
943 int num_to_save
= *high_to_save
- *low_to_save
+ 1;
944 enum machine_mode save_mode
945 = mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
948 /* If we don't have the required alignment, must do this in BLKmode. */
949 if ((*low_to_save
& (MIN (GET_MODE_SIZE (save_mode
),
950 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
953 #ifdef ARGS_GROW_DOWNWARD
955 = gen_rtx_MEM (save_mode
,
956 memory_address (save_mode
,
957 plus_constant (argblock
,
960 stack_area
= gen_rtx_MEM (save_mode
,
961 memory_address (save_mode
,
962 plus_constant (argblock
,
966 set_mem_align (stack_area
, PARM_BOUNDARY
);
967 if (save_mode
== BLKmode
)
969 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
970 /* Cannot use emit_block_move here because it can be done by a
971 library call which in turn gets into this place again and deadly
972 infinite recursion happens. */
973 move_by_pieces (validize_mem (save_area
), stack_area
, num_to_save
,
978 save_area
= gen_reg_rtx (save_mode
);
979 emit_move_insn (save_area
, stack_area
);
987 restore_fixed_argument_area (save_area
, argblock
, high_to_save
, low_to_save
)
993 enum machine_mode save_mode
= GET_MODE (save_area
);
994 #ifdef ARGS_GROW_DOWNWARD
996 = gen_rtx_MEM (save_mode
,
997 memory_address (save_mode
,
998 plus_constant (argblock
,
1002 = gen_rtx_MEM (save_mode
,
1003 memory_address (save_mode
,
1004 plus_constant (argblock
,
1008 if (save_mode
!= BLKmode
)
1009 emit_move_insn (stack_area
, save_area
);
1011 /* Cannot use emit_block_move here because it can be done by a library
1012 call which in turn gets into this place again and deadly infinite
1013 recursion happens. */
1014 move_by_pieces (stack_area
, validize_mem (save_area
),
1015 high_to_save
- low_to_save
+ 1, PARM_BOUNDARY
);
1017 #endif /* REG_PARM_STACK_SPACE */
1019 /* If any elements in ARGS refer to parameters that are to be passed in
1020 registers, but not in memory, and whose alignment does not permit a
1021 direct copy into registers. Copy the values into a group of pseudos
1022 which we will later copy into the appropriate hard registers.
1024 Pseudos for each unaligned argument will be stored into the array
1025 args[argnum].aligned_regs. The caller is responsible for deallocating
1026 the aligned_regs array if it is nonzero. */
1029 store_unaligned_arguments_into_pseudos (args
, num_actuals
)
1030 struct arg_data
*args
;
1035 for (i
= 0; i
< num_actuals
; i
++)
1036 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
1037 && args
[i
].mode
== BLKmode
1038 && (TYPE_ALIGN (TREE_TYPE (args
[i
].tree_value
))
1039 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
1041 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1042 int big_endian_correction
= 0;
1044 args
[i
].n_aligned_regs
1045 = args
[i
].partial
? args
[i
].partial
1046 : (bytes
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1048 args
[i
].aligned_regs
= (rtx
*) xmalloc (sizeof (rtx
)
1049 * args
[i
].n_aligned_regs
);
1051 /* Structures smaller than a word are aligned to the least
1052 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1053 this means we must skip the empty high order bytes when
1054 calculating the bit offset. */
1055 if (BYTES_BIG_ENDIAN
1056 && !FUNCTION_ARG_REG_LITTLE_ENDIAN
1057 && bytes
< UNITS_PER_WORD
)
1058 big_endian_correction
= (BITS_PER_WORD
- (bytes
* BITS_PER_UNIT
));
1060 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1062 rtx reg
= gen_reg_rtx (word_mode
);
1063 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
1064 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
1066 args
[i
].aligned_regs
[j
] = reg
;
1068 /* There is no need to restrict this code to loading items
1069 in TYPE_ALIGN sized hunks. The bitfield instructions can
1070 load up entire word sized registers efficiently.
1072 ??? This may not be needed anymore.
1073 We use to emit a clobber here but that doesn't let later
1074 passes optimize the instructions we emit. By storing 0 into
1075 the register later passes know the first AND to zero out the
1076 bitfield being set in the register is unnecessary. The store
1077 of 0 will be deleted as will at least the first AND. */
1079 emit_move_insn (reg
, const0_rtx
);
1081 bytes
-= bitsize
/ BITS_PER_UNIT
;
1082 store_bit_field (reg
, bitsize
, big_endian_correction
, word_mode
,
1083 extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
1084 word_mode
, word_mode
,
1091 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1094 NUM_ACTUALS is the total number of parameters.
1096 N_NAMED_ARGS is the total number of named arguments.
1098 FNDECL is the tree code for the target of this call (if known)
1100 ARGS_SO_FAR holds state needed by the target to know where to place
1103 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1104 for arguments which are passed in registers.
1106 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1107 and may be modified by this routine.
1109 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1110 flags which may may be modified by this routine. */
1113 initialize_argument_information (num_actuals
, args
, args_size
, n_named_args
,
1114 actparms
, fndecl
, args_so_far
,
1115 reg_parm_stack_space
, old_stack_level
,
1116 old_pending_adj
, must_preallocate
,
1118 int num_actuals ATTRIBUTE_UNUSED
;
1119 struct arg_data
*args
;
1120 struct args_size
*args_size
;
1121 int n_named_args ATTRIBUTE_UNUSED
;
1124 CUMULATIVE_ARGS
*args_so_far
;
1125 int reg_parm_stack_space
;
1126 rtx
*old_stack_level
;
1127 int *old_pending_adj
;
1128 int *must_preallocate
;
1131 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1134 /* Count arg position in order args appear. */
1137 struct args_size alignment_pad
;
1141 args_size
->constant
= 0;
1144 /* In this loop, we consider args in the order they are written.
1145 We fill up ARGS from the front or from the back if necessary
1146 so that in any case the first arg to be pushed ends up at the front. */
1148 if (PUSH_ARGS_REVERSED
)
1150 i
= num_actuals
- 1, inc
= -1;
1151 /* In this case, must reverse order of args
1152 so that we compute and push the last arg first. */
1159 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1160 for (p
= actparms
, argpos
= 0; p
; p
= TREE_CHAIN (p
), i
+= inc
, argpos
++)
1162 tree type
= TREE_TYPE (TREE_VALUE (p
));
1164 enum machine_mode mode
;
1166 args
[i
].tree_value
= TREE_VALUE (p
);
1168 /* Replace erroneous argument with constant zero. */
1169 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1170 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1172 /* If TYPE is a transparent union, pass things the way we would
1173 pass the first field of the union. We have already verified that
1174 the modes are the same. */
1175 if (TREE_CODE (type
) == UNION_TYPE
&& TYPE_TRANSPARENT_UNION (type
))
1176 type
= TREE_TYPE (TYPE_FIELDS (type
));
1178 /* Decide where to pass this arg.
1180 args[i].reg is nonzero if all or part is passed in registers.
1182 args[i].partial is nonzero if part but not all is passed in registers,
1183 and the exact value says how many words are passed in registers.
1185 args[i].pass_on_stack is nonzero if the argument must at least be
1186 computed on the stack. It may then be loaded back into registers
1187 if args[i].reg is nonzero.
1189 These decisions are driven by the FUNCTION_... macros and must agree
1190 with those made by function.c. */
1192 /* See if this argument should be passed by invisible reference. */
1193 if ((TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1194 && contains_placeholder_p (TYPE_SIZE (type
)))
1195 || TREE_ADDRESSABLE (type
)
1196 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1197 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far
, TYPE_MODE (type
),
1198 type
, argpos
< n_named_args
)
1202 /* If we're compiling a thunk, pass through invisible
1203 references instead of making a copy. */
1204 if (current_function_is_thunk
1205 #ifdef FUNCTION_ARG_CALLEE_COPIES
1206 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far
, TYPE_MODE (type
),
1207 type
, argpos
< n_named_args
)
1208 /* If it's in a register, we must make a copy of it too. */
1209 /* ??? Is this a sufficient test? Is there a better one? */
1210 && !(TREE_CODE (args
[i
].tree_value
) == VAR_DECL
1211 && REG_P (DECL_RTL (args
[i
].tree_value
)))
1212 && ! TREE_ADDRESSABLE (type
))
1216 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1217 new object from the argument. If we are passing by
1218 invisible reference, the callee will do that for us, so we
1219 can strip off the TARGET_EXPR. This is not always safe,
1220 but it is safe in the only case where this is a useful
1221 optimization; namely, when the argument is a plain object.
1222 In that case, the frontend is just asking the backend to
1223 make a bitwise copy of the argument. */
1225 if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1226 && (DECL_P (TREE_OPERAND (args
[i
].tree_value
, 1)))
1227 && ! REG_P (DECL_RTL (TREE_OPERAND (args
[i
].tree_value
, 1))))
1228 args
[i
].tree_value
= TREE_OPERAND (args
[i
].tree_value
, 1);
1230 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1231 build_pointer_type (type
),
1232 args
[i
].tree_value
);
1233 type
= build_pointer_type (type
);
1235 else if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
)
1237 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1238 We implement this by passing the address of the temporary
1239 rather than expanding it into another allocated slot. */
1240 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1241 build_pointer_type (type
),
1242 args
[i
].tree_value
);
1243 type
= build_pointer_type (type
);
1247 /* We make a copy of the object and pass the address to the
1248 function being called. */
1251 if (!COMPLETE_TYPE_P (type
)
1252 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1253 || (flag_stack_check
&& ! STACK_CHECK_BUILTIN
1254 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type
),
1255 STACK_CHECK_MAX_VAR_SIZE
))))
1257 /* This is a variable-sized object. Make space on the stack
1259 rtx size_rtx
= expr_size (TREE_VALUE (p
));
1261 if (*old_stack_level
== 0)
1263 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1264 *old_pending_adj
= pending_stack_adjust
;
1265 pending_stack_adjust
= 0;
1268 copy
= gen_rtx_MEM (BLKmode
,
1269 allocate_dynamic_stack_space
1270 (size_rtx
, NULL_RTX
, TYPE_ALIGN (type
)));
1271 set_mem_attributes (copy
, type
, 1);
1274 copy
= assign_temp (type
, 0, 1, 0);
1276 store_expr (args
[i
].tree_value
, copy
, 0);
1277 *ecf_flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
1279 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1280 build_pointer_type (type
),
1281 make_tree (type
, copy
));
1282 type
= build_pointer_type (type
);
1286 mode
= TYPE_MODE (type
);
1287 unsignedp
= TREE_UNSIGNED (type
);
1289 #ifdef PROMOTE_FUNCTION_ARGS
1290 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
1293 args
[i
].unsignedp
= unsignedp
;
1294 args
[i
].mode
= mode
;
1296 args
[i
].reg
= FUNCTION_ARG (*args_so_far
, mode
, type
,
1297 argpos
< n_named_args
);
1298 #ifdef FUNCTION_INCOMING_ARG
1299 /* If this is a sibling call and the machine has register windows, the
1300 register window has to be unwinded before calling the routine, so
1301 arguments have to go into the incoming registers. */
1302 args
[i
].tail_call_reg
= FUNCTION_INCOMING_ARG (*args_so_far
, mode
, type
,
1303 argpos
< n_named_args
);
1305 args
[i
].tail_call_reg
= args
[i
].reg
;
1308 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1311 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far
, mode
, type
,
1312 argpos
< n_named_args
);
1315 args
[i
].pass_on_stack
= MUST_PASS_IN_STACK (mode
, type
);
1317 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1318 it means that we are to pass this arg in the register(s) designated
1319 by the PARALLEL, but also to pass it in the stack. */
1320 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1321 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1322 args
[i
].pass_on_stack
= 1;
1324 /* If this is an addressable type, we must preallocate the stack
1325 since we must evaluate the object into its final location.
1327 If this is to be passed in both registers and the stack, it is simpler
1329 if (TREE_ADDRESSABLE (type
)
1330 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1331 *must_preallocate
= 1;
1333 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1334 we cannot consider this function call constant. */
1335 if (TREE_ADDRESSABLE (type
))
1336 *ecf_flags
&= ~ECF_LIBCALL_BLOCK
;
1338 /* Compute the stack-size of this argument. */
1339 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1340 || reg_parm_stack_space
> 0
1341 || args
[i
].pass_on_stack
)
1342 locate_and_pad_parm (mode
, type
,
1343 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1348 fndecl
, args_size
, &args
[i
].offset
,
1349 &args
[i
].size
, &alignment_pad
);
1351 #ifndef ARGS_GROW_DOWNWARD
1352 args
[i
].slot_offset
= *args_size
;
1355 args
[i
].alignment_pad
= alignment_pad
;
1357 /* If a part of the arg was put into registers,
1358 don't include that part in the amount pushed. */
1359 if (reg_parm_stack_space
== 0 && ! args
[i
].pass_on_stack
)
1360 args
[i
].size
.constant
-= ((args
[i
].partial
* UNITS_PER_WORD
)
1361 / (PARM_BOUNDARY
/ BITS_PER_UNIT
)
1362 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
1364 /* Update ARGS_SIZE, the total stack space for args so far. */
1366 args_size
->constant
+= args
[i
].size
.constant
;
1367 if (args
[i
].size
.var
)
1369 ADD_PARM_SIZE (*args_size
, args
[i
].size
.var
);
1372 /* Since the slot offset points to the bottom of the slot,
1373 we must record it after incrementing if the args grow down. */
1374 #ifdef ARGS_GROW_DOWNWARD
1375 args
[i
].slot_offset
= *args_size
;
1377 args
[i
].slot_offset
.constant
= -args_size
->constant
;
1379 SUB_PARM_SIZE (args
[i
].slot_offset
, args_size
->var
);
1382 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1383 have been used, etc. */
1385 FUNCTION_ARG_ADVANCE (*args_so_far
, TYPE_MODE (type
), type
,
1386 argpos
< n_named_args
);
1390 /* Update ARGS_SIZE to contain the total size for the argument block.
1391 Return the original constant component of the argument block's size.
1393 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1394 for arguments passed in registers. */
1397 compute_argument_block_size (reg_parm_stack_space
, args_size
,
1398 preferred_stack_boundary
)
1399 int reg_parm_stack_space
;
1400 struct args_size
*args_size
;
1401 int preferred_stack_boundary ATTRIBUTE_UNUSED
;
1403 int unadjusted_args_size
= args_size
->constant
;
1405 /* For accumulate outgoing args mode we don't need to align, since the frame
1406 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1407 backends from generating misaligned frame sizes. */
1408 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1409 preferred_stack_boundary
= STACK_BOUNDARY
;
1411 /* Compute the actual size of the argument block required. The variable
1412 and constant sizes must be combined, the size may have to be rounded,
1413 and there may be a minimum required size. */
1417 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1418 args_size
->constant
= 0;
1420 preferred_stack_boundary
/= BITS_PER_UNIT
;
1421 if (preferred_stack_boundary
> 1)
1423 /* We don't handle this case yet. To handle it correctly we have
1424 to add the delta, round and subtract the delta.
1425 Currently no machine description requires this support. */
1426 if (stack_pointer_delta
& (preferred_stack_boundary
- 1))
1428 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1431 if (reg_parm_stack_space
> 0)
1434 = size_binop (MAX_EXPR
, args_size
->var
,
1435 ssize_int (reg_parm_stack_space
));
1437 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1438 /* The area corresponding to register parameters is not to count in
1439 the size of the block we need. So make the adjustment. */
1441 = size_binop (MINUS_EXPR
, args_size
->var
,
1442 ssize_int (reg_parm_stack_space
));
1448 preferred_stack_boundary
/= BITS_PER_UNIT
;
1449 if (preferred_stack_boundary
< 1)
1450 preferred_stack_boundary
= 1;
1451 args_size
->constant
= (((args_size
->constant
1452 + stack_pointer_delta
1453 + preferred_stack_boundary
- 1)
1454 / preferred_stack_boundary
1455 * preferred_stack_boundary
)
1456 - stack_pointer_delta
);
1458 args_size
->constant
= MAX (args_size
->constant
,
1459 reg_parm_stack_space
);
1461 #ifdef MAYBE_REG_PARM_STACK_SPACE
1462 if (reg_parm_stack_space
== 0)
1463 args_size
->constant
= 0;
1466 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1467 args_size
->constant
-= reg_parm_stack_space
;
1470 return unadjusted_args_size
;
1473 /* Precompute parameters as needed for a function call.
1475 FLAGS is mask of ECF_* constants.
1477 NUM_ACTUALS is the number of arguments.
1479 ARGS is an array containing information for each argument; this
1480 routine fills in the INITIAL_VALUE and VALUE fields for each
1481 precomputed argument. */
1484 precompute_arguments (flags
, num_actuals
, args
)
1487 struct arg_data
*args
;
1491 /* If this function call is cse'able, precompute all the parameters.
1492 Note that if the parameter is constructed into a temporary, this will
1493 cause an additional copy because the parameter will be constructed
1494 into a temporary location and then copied into the outgoing arguments.
1495 If a parameter contains a call to alloca and this function uses the
1496 stack, precompute the parameter. */
1498 /* If we preallocated the stack space, and some arguments must be passed
1499 on the stack, then we must precompute any parameter which contains a
1500 function call which will store arguments on the stack.
1501 Otherwise, evaluating the parameter may clobber previous parameters
1502 which have already been stored into the stack. (we have code to avoid
1503 such case by saving the outgoing stack arguments, but it results in
1506 for (i
= 0; i
< num_actuals
; i
++)
1507 if ((flags
& ECF_LIBCALL_BLOCK
)
1508 || calls_function (args
[i
].tree_value
, !ACCUMULATE_OUTGOING_ARGS
))
1510 enum machine_mode mode
;
1512 /* If this is an addressable type, we cannot pre-evaluate it. */
1513 if (TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
)))
1517 = expand_expr (args
[i
].tree_value
, NULL_RTX
, VOIDmode
, 0);
1519 /* ANSI doesn't require a sequence point here,
1520 but PCC has one, so this will avoid some problems. */
1523 args
[i
].initial_value
= args
[i
].value
1524 = protect_from_queue (args
[i
].value
, 0);
1526 mode
= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
));
1527 if (mode
!= args
[i
].mode
)
1530 = convert_modes (args
[i
].mode
, mode
,
1531 args
[i
].value
, args
[i
].unsignedp
);
1532 #ifdef PROMOTE_FOR_CALL_ONLY
1533 /* CSE will replace this only if it contains args[i].value
1534 pseudo, so convert it down to the declared mode using
1536 if (GET_CODE (args
[i
].value
) == REG
1537 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
)
1539 args
[i
].initial_value
1540 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1541 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1542 SUBREG_PROMOTED_UNSIGNED_SET (args
[i
].initial_value
,
1550 /* Given the current state of MUST_PREALLOCATE and information about
1551 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1552 compute and return the final value for MUST_PREALLOCATE. */
1555 finalize_must_preallocate (must_preallocate
, num_actuals
, args
, args_size
)
1556 int must_preallocate
;
1558 struct arg_data
*args
;
1559 struct args_size
*args_size
;
1561 /* See if we have or want to preallocate stack space.
1563 If we would have to push a partially-in-regs parm
1564 before other stack parms, preallocate stack space instead.
1566 If the size of some parm is not a multiple of the required stack
1567 alignment, we must preallocate.
1569 If the total size of arguments that would otherwise create a copy in
1570 a temporary (such as a CALL) is more than half the total argument list
1571 size, preallocation is faster.
1573 Another reason to preallocate is if we have a machine (like the m88k)
1574 where stack alignment is required to be maintained between every
1575 pair of insns, not just when the call is made. However, we assume here
1576 that such machines either do not have push insns (and hence preallocation
1577 would occur anyway) or the problem is taken care of with
1580 if (! must_preallocate
)
1582 int partial_seen
= 0;
1583 int copy_to_evaluate_size
= 0;
1586 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1588 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1590 else if (partial_seen
&& args
[i
].reg
== 0)
1591 must_preallocate
= 1;
1593 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1594 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1595 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1596 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1597 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1598 copy_to_evaluate_size
1599 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1602 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1603 && args_size
->constant
> 0)
1604 must_preallocate
= 1;
1606 return must_preallocate
;
1609 /* If we preallocated stack space, compute the address of each argument
1610 and store it into the ARGS array.
1612 We need not ensure it is a valid memory address here; it will be
1613 validized when it is used.
1615 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1618 compute_argument_addresses (args
, argblock
, num_actuals
)
1619 struct arg_data
*args
;
1625 rtx arg_reg
= argblock
;
1626 int i
, arg_offset
= 0;
1628 if (GET_CODE (argblock
) == PLUS
)
1629 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1631 for (i
= 0; i
< num_actuals
; i
++)
1633 rtx offset
= ARGS_SIZE_RTX (args
[i
].offset
);
1634 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].slot_offset
);
1637 /* Skip this parm if it will not be passed on the stack. */
1638 if (! args
[i
].pass_on_stack
&& args
[i
].reg
!= 0)
1641 if (GET_CODE (offset
) == CONST_INT
)
1642 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1644 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1646 addr
= plus_constant (addr
, arg_offset
);
1647 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1648 set_mem_attributes (args
[i
].stack
,
1649 TREE_TYPE (args
[i
].tree_value
), 1);
1651 if (GET_CODE (slot_offset
) == CONST_INT
)
1652 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1654 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1656 addr
= plus_constant (addr
, arg_offset
);
1657 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1658 set_mem_attributes (args
[i
].stack_slot
,
1659 TREE_TYPE (args
[i
].tree_value
), 1);
1661 /* Function incoming arguments may overlap with sibling call
1662 outgoing arguments and we cannot allow reordering of reads
1663 from function arguments with stores to outgoing arguments
1664 of sibling calls. */
1665 set_mem_alias_set (args
[i
].stack
, 0);
1666 set_mem_alias_set (args
[i
].stack_slot
, 0);
1671 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1672 in a call instruction.
1674 FNDECL is the tree node for the target function. For an indirect call
1675 FNDECL will be NULL_TREE.
1677 EXP is the CALL_EXPR for this call. */
1680 rtx_for_function_call (fndecl
, exp
)
1686 /* Get the function to call, in the form of RTL. */
1689 /* If this is the first use of the function, see if we need to
1690 make an external definition for it. */
1691 if (! TREE_USED (fndecl
))
1693 assemble_external (fndecl
);
1694 TREE_USED (fndecl
) = 1;
1697 /* Get a SYMBOL_REF rtx for the function address. */
1698 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1701 /* Generate an rtx (probably a pseudo-register) for the address. */
1706 = expand_expr (TREE_OPERAND (exp
, 0), NULL_RTX
, VOIDmode
, 0);
1707 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1713 /* Do the register loads required for any wholly-register parms or any
1714 parms which are passed both on the stack and in a register. Their
1715 expressions were already evaluated.
1717 Mark all register-parms as living through the call, putting these USE
1718 insns in the CALL_INSN_FUNCTION_USAGE field. */
1721 load_register_parameters (args
, num_actuals
, call_fusage
, flags
)
1722 struct arg_data
*args
;
1729 #ifdef LOAD_ARGS_REVERSED
1730 for (i
= num_actuals
- 1; i
>= 0; i
--)
1732 for (i
= 0; i
< num_actuals
; i
++)
1735 rtx reg
= ((flags
& ECF_SIBCALL
)
1736 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1737 int partial
= args
[i
].partial
;
1742 /* Set to non-negative if must move a word at a time, even if just
1743 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1744 we just use a normal move insn. This value can be zero if the
1745 argument is a zero size structure with no fields. */
1746 nregs
= (partial
? partial
1747 : (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1748 ? ((int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
))
1749 + (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
)
1752 /* Handle calls that pass values in multiple non-contiguous
1753 locations. The Irix 6 ABI has examples of this. */
1755 if (GET_CODE (reg
) == PARALLEL
)
1756 emit_group_load (reg
, args
[i
].value
,
1757 int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
)));
1759 /* If simple case, just do move. If normal partial, store_one_arg
1760 has already loaded the register for us. In all other cases,
1761 load the register(s) from memory. */
1763 else if (nregs
== -1)
1764 emit_move_insn (reg
, args
[i
].value
);
1766 /* If we have pre-computed the values to put in the registers in
1767 the case of non-aligned structures, copy them in now. */
1769 else if (args
[i
].n_aligned_regs
!= 0)
1770 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1771 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1772 args
[i
].aligned_regs
[j
]);
1774 else if (partial
== 0 || args
[i
].pass_on_stack
)
1775 move_block_to_reg (REGNO (reg
),
1776 validize_mem (args
[i
].value
), nregs
,
1779 /* Handle calls that pass values in multiple non-contiguous
1780 locations. The Irix 6 ABI has examples of this. */
1781 if (GET_CODE (reg
) == PARALLEL
)
1782 use_group_regs (call_fusage
, reg
);
1783 else if (nregs
== -1)
1784 use_reg (call_fusage
, reg
);
1786 use_regs (call_fusage
, REGNO (reg
), nregs
== 0 ? 1 : nregs
);
1791 /* Try to integrate function. See expand_inline_function for documentation
1792 about the parameters. */
1795 try_to_integrate (fndecl
, actparms
, target
, ignore
, type
, structure_value_addr
)
1801 rtx structure_value_addr
;
1806 rtx old_stack_level
= 0;
1807 int reg_parm_stack_space
= 0;
1809 #ifdef REG_PARM_STACK_SPACE
1810 #ifdef MAYBE_REG_PARM_STACK_SPACE
1811 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
1813 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
1817 before_call
= get_last_insn ();
1819 timevar_push (TV_INTEGRATION
);
1821 temp
= expand_inline_function (fndecl
, actparms
, target
,
1823 structure_value_addr
);
1825 timevar_pop (TV_INTEGRATION
);
1827 /* If inlining succeeded, return. */
1828 if (temp
!= (rtx
) (size_t) - 1)
1830 if (ACCUMULATE_OUTGOING_ARGS
)
1832 /* If the outgoing argument list must be preserved, push
1833 the stack before executing the inlined function if it
1836 for (i
= reg_parm_stack_space
- 1; i
>= 0; i
--)
1837 if (i
< highest_outgoing_arg_in_use
&& stack_usage_map
[i
] != 0)
1840 if (stack_arg_under_construction
|| i
>= 0)
1843 = before_call
? NEXT_INSN (before_call
) : get_insns ();
1844 rtx insn
= NULL_RTX
, seq
;
1846 /* Look for a call in the inline function code.
1847 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1848 nonzero then there is a call and it is not necessary
1849 to scan the insns. */
1851 if (DECL_SAVED_INSNS (fndecl
)->outgoing_args_size
== 0)
1852 for (insn
= first_insn
; insn
; insn
= NEXT_INSN (insn
))
1853 if (GET_CODE (insn
) == CALL_INSN
)
1858 /* Reserve enough stack space so that the largest
1859 argument list of any function call in the inline
1860 function does not overlap the argument list being
1861 evaluated. This is usually an overestimate because
1862 allocate_dynamic_stack_space reserves space for an
1863 outgoing argument list in addition to the requested
1864 space, but there is no way to ask for stack space such
1865 that an argument list of a certain length can be
1868 Add the stack space reserved for register arguments, if
1869 any, in the inline function. What is really needed is the
1870 largest value of reg_parm_stack_space in the inline
1871 function, but that is not available. Using the current
1872 value of reg_parm_stack_space is wrong, but gives
1873 correct results on all supported machines. */
1875 int adjust
= (DECL_SAVED_INSNS (fndecl
)->outgoing_args_size
1876 + reg_parm_stack_space
);
1879 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
1880 allocate_dynamic_stack_space (GEN_INT (adjust
),
1881 NULL_RTX
, BITS_PER_UNIT
);
1884 emit_insn_before (seq
, first_insn
);
1885 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1890 /* If the result is equivalent to TARGET, return TARGET to simplify
1891 checks in store_expr. They can be equivalent but not equal in the
1892 case of a function that returns BLKmode. */
1893 if (temp
!= target
&& rtx_equal_p (temp
, target
))
1898 /* If inlining failed, mark FNDECL as needing to be compiled
1899 separately after all. If function was declared inline,
1901 if (DECL_INLINE (fndecl
) && warn_inline
&& !flag_no_inline
1902 && optimize
> 0 && !TREE_ADDRESSABLE (fndecl
))
1904 warning_with_decl (fndecl
, "inlining failed in call to `%s'");
1905 warning ("called from here");
1907 (*lang_hooks
.mark_addressable
) (fndecl
);
1908 return (rtx
) (size_t) - 1;
1911 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1912 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1913 bytes, then we would need to push some additional bytes to pad the
1914 arguments. So, we compute an adjust to the stack pointer for an
1915 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1916 bytes. Then, when the arguments are pushed the stack will be perfectly
1917 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1918 be popped after the call. Returns the adjustment. */
1921 combine_pending_stack_adjustment_and_call (unadjusted_args_size
,
1923 preferred_unit_stack_boundary
)
1924 int unadjusted_args_size
;
1925 struct args_size
*args_size
;
1926 int preferred_unit_stack_boundary
;
1928 /* The number of bytes to pop so that the stack will be
1929 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1930 HOST_WIDE_INT adjustment
;
1931 /* The alignment of the stack after the arguments are pushed, if we
1932 just pushed the arguments without adjust the stack here. */
1933 HOST_WIDE_INT unadjusted_alignment
;
1935 unadjusted_alignment
1936 = ((stack_pointer_delta
+ unadjusted_args_size
)
1937 % preferred_unit_stack_boundary
);
1939 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1940 as possible -- leaving just enough left to cancel out the
1941 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1942 PENDING_STACK_ADJUST is non-negative, and congruent to
1943 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1945 /* Begin by trying to pop all the bytes. */
1946 unadjusted_alignment
1947 = (unadjusted_alignment
1948 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1949 adjustment
= pending_stack_adjust
;
1950 /* Push enough additional bytes that the stack will be aligned
1951 after the arguments are pushed. */
1952 if (preferred_unit_stack_boundary
> 1)
1954 if (unadjusted_alignment
> 0)
1955 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1957 adjustment
+= unadjusted_alignment
;
1960 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1961 bytes after the call. The right number is the entire
1962 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1963 by the arguments in the first place. */
1965 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1970 /* Scan X expression if it does not dereference any argument slots
1971 we already clobbered by tail call arguments (as noted in stored_args_map
1973 Return non-zero if X expression dereferences such argument slots,
1977 check_sibcall_argument_overlap_1 (x
)
1988 code
= GET_CODE (x
);
1992 if (XEXP (x
, 0) == current_function_internal_arg_pointer
)
1994 else if (GET_CODE (XEXP (x
, 0)) == PLUS
1995 && XEXP (XEXP (x
, 0), 0) ==
1996 current_function_internal_arg_pointer
1997 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
)
1998 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
2002 #ifdef ARGS_GROW_DOWNWARD
2003 i
= -i
- GET_MODE_SIZE (GET_MODE (x
));
2006 for (k
= 0; k
< GET_MODE_SIZE (GET_MODE (x
)); k
++)
2007 if (i
+ k
< stored_args_map
->n_bits
2008 && TEST_BIT (stored_args_map
, i
+ k
))
2014 /* Scan all subexpressions. */
2015 fmt
= GET_RTX_FORMAT (code
);
2016 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
2020 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
2023 else if (*fmt
== 'E')
2025 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2026 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
2033 /* Scan sequence after INSN if it does not dereference any argument slots
2034 we already clobbered by tail call arguments (as noted in stored_args_map
2035 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2036 Return non-zero if sequence after INSN dereferences such argument slots,
2040 check_sibcall_argument_overlap (insn
, arg
)
2042 struct arg_data
*arg
;
2046 if (insn
== NULL_RTX
)
2047 insn
= get_insns ();
2049 insn
= NEXT_INSN (insn
);
2051 for (; insn
; insn
= NEXT_INSN (insn
))
2053 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
2056 #ifdef ARGS_GROW_DOWNWARD
2057 low
= -arg
->slot_offset
.constant
- arg
->size
.constant
;
2059 low
= arg
->slot_offset
.constant
;
2062 for (high
= low
+ arg
->size
.constant
; low
< high
; low
++)
2063 SET_BIT (stored_args_map
, low
);
2064 return insn
!= NULL_RTX
;
2067 /* Generate all the code for a function call
2068 and return an rtx for its value.
2069 Store the value in TARGET (specified as an rtx) if convenient.
2070 If the value is stored in TARGET then TARGET is returned.
2071 If IGNORE is nonzero, then we ignore the value of the function call. */
2074 expand_call (exp
, target
, ignore
)
2079 /* Nonzero if we are currently expanding a call. */
2080 static int currently_expanding_call
= 0;
2082 /* List of actual parameters. */
2083 tree actparms
= TREE_OPERAND (exp
, 1);
2084 /* RTX for the function to be called. */
2086 /* Sequence of insns to perform a tail recursive "call". */
2087 rtx tail_recursion_insns
= NULL_RTX
;
2088 /* Sequence of insns to perform a normal "call". */
2089 rtx normal_call_insns
= NULL_RTX
;
2090 /* Sequence of insns to perform a tail recursive "call". */
2091 rtx tail_call_insns
= NULL_RTX
;
2092 /* Data type of the function. */
2094 /* Declaration of the function being called,
2095 or 0 if the function is computed (not known by name). */
2098 int try_tail_call
= 1;
2099 int try_tail_recursion
= 1;
2102 /* Register in which non-BLKmode value will be returned,
2103 or 0 if no value or if value is BLKmode. */
2105 /* Address where we should return a BLKmode value;
2106 0 if value not BLKmode. */
2107 rtx structure_value_addr
= 0;
2108 /* Nonzero if that address is being passed by treating it as
2109 an extra, implicit first parameter. Otherwise,
2110 it is passed by being copied directly into struct_value_rtx. */
2111 int structure_value_addr_parm
= 0;
2112 /* Size of aggregate value wanted, or zero if none wanted
2113 or if we are using the non-reentrant PCC calling convention
2114 or expecting the value in registers. */
2115 HOST_WIDE_INT struct_value_size
= 0;
2116 /* Nonzero if called function returns an aggregate in memory PCC style,
2117 by returning the address of where to find it. */
2118 int pcc_struct_value
= 0;
2120 /* Number of actual parameters in this call, including struct value addr. */
2122 /* Number of named args. Args after this are anonymous ones
2123 and they must all go on the stack. */
2126 /* Vector of information about each argument.
2127 Arguments are numbered in the order they will be pushed,
2128 not the order they are written. */
2129 struct arg_data
*args
;
2131 /* Total size in bytes of all the stack-parms scanned so far. */
2132 struct args_size args_size
;
2133 struct args_size adjusted_args_size
;
2134 /* Size of arguments before any adjustments (such as rounding). */
2135 int unadjusted_args_size
;
2136 /* Data on reg parms scanned so far. */
2137 CUMULATIVE_ARGS args_so_far
;
2138 /* Nonzero if a reg parm has been scanned. */
2140 /* Nonzero if this is an indirect function call. */
2142 /* Nonzero if we must avoid push-insns in the args for this call.
2143 If stack space is allocated for register parameters, but not by the
2144 caller, then it is preallocated in the fixed part of the stack frame.
2145 So the entire argument block must then be preallocated (i.e., we
2146 ignore PUSH_ROUNDING in that case). */
2148 int must_preallocate
= !PUSH_ARGS
;
2150 /* Size of the stack reserved for parameter registers. */
2151 int reg_parm_stack_space
= 0;
2153 /* Address of space preallocated for stack parms
2154 (on machines that lack push insns), or 0 if space not preallocated. */
2157 /* Mask of ECF_ flags. */
2159 /* Nonzero if this is a call to an inline function. */
2160 int is_integrable
= 0;
2161 #ifdef REG_PARM_STACK_SPACE
2162 /* Define the boundary of the register parm stack space that needs to be
2164 int low_to_save
= -1, high_to_save
;
2165 rtx save_area
= 0; /* Place that it is saved */
2168 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
2169 char *initial_stack_usage_map
= stack_usage_map
;
2170 int old_stack_arg_under_construction
= 0;
2172 rtx old_stack_level
= 0;
2173 int old_pending_adj
= 0;
2174 int old_inhibit_defer_pop
= inhibit_defer_pop
;
2175 int old_stack_allocated
;
2177 tree p
= TREE_OPERAND (exp
, 0);
2179 /* The alignment of the stack, in bits. */
2180 HOST_WIDE_INT preferred_stack_boundary
;
2181 /* The alignment of the stack, in bytes. */
2182 HOST_WIDE_INT preferred_unit_stack_boundary
;
2184 /* See if this is "nothrow" function call. */
2185 if (TREE_NOTHROW (exp
))
2186 flags
|= ECF_NOTHROW
;
2188 /* See if we can find a DECL-node for the actual function.
2189 As a result, decide whether this is a call to an integrable function. */
2191 fndecl
= get_callee_fndecl (exp
);
2195 && fndecl
!= current_function_decl
2196 && DECL_INLINE (fndecl
)
2197 && DECL_SAVED_INSNS (fndecl
)
2198 && DECL_SAVED_INSNS (fndecl
)->inlinable
)
2200 else if (! TREE_ADDRESSABLE (fndecl
))
2202 /* In case this function later becomes inlinable,
2203 record that there was already a non-inline call to it.
2205 Use abstraction instead of setting TREE_ADDRESSABLE
2207 if (DECL_INLINE (fndecl
) && warn_inline
&& !flag_no_inline
2210 warning_with_decl (fndecl
, "can't inline call to `%s'");
2211 warning ("called from here");
2213 (*lang_hooks
.mark_addressable
) (fndecl
);
2216 flags
|= flags_from_decl_or_type (fndecl
);
2219 /* If we don't have specific function to call, see if we have a
2220 attributes set in the type. */
2222 flags
|= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p
)));
2224 #ifdef REG_PARM_STACK_SPACE
2225 #ifdef MAYBE_REG_PARM_STACK_SPACE
2226 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
2228 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
2232 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2233 if (reg_parm_stack_space
> 0 && PUSH_ARGS
)
2234 must_preallocate
= 1;
2237 /* Warn if this value is an aggregate type,
2238 regardless of which calling convention we are using for it. */
2239 if (warn_aggregate_return
&& AGGREGATE_TYPE_P (TREE_TYPE (exp
)))
2240 warning ("function call has aggregate value");
2242 /* Set up a place to return a structure. */
2244 /* Cater to broken compilers. */
2245 if (aggregate_value_p (exp
))
2247 /* This call returns a big structure. */
2248 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
2250 #ifdef PCC_STATIC_STRUCT_RETURN
2252 pcc_struct_value
= 1;
2253 /* Easier than making that case work right. */
2256 /* In case this is a static function, note that it has been
2258 if (! TREE_ADDRESSABLE (fndecl
))
2259 (*lang_hooks
.mark_addressable
) (fndecl
);
2263 #else /* not PCC_STATIC_STRUCT_RETURN */
2265 struct_value_size
= int_size_in_bytes (TREE_TYPE (exp
));
2267 if (target
&& GET_CODE (target
) == MEM
)
2268 structure_value_addr
= XEXP (target
, 0);
2271 /* For variable-sized objects, we must be called with a target
2272 specified. If we were to allocate space on the stack here,
2273 we would have no way of knowing when to free it. */
2274 rtx d
= assign_temp (TREE_TYPE (exp
), 1, 1, 1);
2276 mark_temp_addr_taken (d
);
2277 structure_value_addr
= XEXP (d
, 0);
2281 #endif /* not PCC_STATIC_STRUCT_RETURN */
2284 /* If called function is inline, try to integrate it. */
2288 rtx temp
= try_to_integrate (fndecl
, actparms
, target
,
2289 ignore
, TREE_TYPE (exp
),
2290 structure_value_addr
);
2291 if (temp
!= (rtx
) (size_t) - 1)
2295 /* Figure out the amount to which the stack should be aligned. */
2296 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2298 /* Operand 0 is a pointer-to-function; get the type of the function. */
2299 funtype
= TREE_TYPE (TREE_OPERAND (exp
, 0));
2300 if (! POINTER_TYPE_P (funtype
))
2302 funtype
= TREE_TYPE (funtype
);
2304 /* See if this is a call to a function that can return more than once
2305 or a call to longjmp or malloc. */
2306 flags
|= special_function_p (fndecl
, flags
);
2308 if (flags
& ECF_MAY_BE_ALLOCA
)
2309 current_function_calls_alloca
= 1;
2311 /* If struct_value_rtx is 0, it means pass the address
2312 as if it were an extra parameter. */
2313 if (structure_value_addr
&& struct_value_rtx
== 0)
2315 /* If structure_value_addr is a REG other than
2316 virtual_outgoing_args_rtx, we can use always use it. If it
2317 is not a REG, we must always copy it into a register.
2318 If it is virtual_outgoing_args_rtx, we must copy it to another
2319 register in some cases. */
2320 rtx temp
= (GET_CODE (structure_value_addr
) != REG
2321 || (ACCUMULATE_OUTGOING_ARGS
2322 && stack_arg_under_construction
2323 && structure_value_addr
== virtual_outgoing_args_rtx
)
2324 ? copy_addr_to_reg (structure_value_addr
)
2325 : structure_value_addr
);
2328 = tree_cons (error_mark_node
,
2329 make_tree (build_pointer_type (TREE_TYPE (funtype
)),
2332 structure_value_addr_parm
= 1;
2335 /* Count the arguments and set NUM_ACTUALS. */
2336 for (p
= actparms
, num_actuals
= 0; p
; p
= TREE_CHAIN (p
))
2339 /* Compute number of named args.
2340 Normally, don't include the last named arg if anonymous args follow.
2341 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2342 (If no anonymous args follow, the result of list_length is actually
2343 one too large. This is harmless.)
2345 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2346 zero, this machine will be able to place unnamed args that were
2347 passed in registers into the stack. So treat all args as named.
2348 This allows the insns emitting for a specific argument list to be
2349 independent of the function declaration.
2351 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2352 reliable way to pass unnamed args in registers, so we must force
2353 them into memory. */
2355 if ((STRICT_ARGUMENT_NAMING
2356 || ! PRETEND_OUTGOING_VARARGS_NAMED
)
2357 && TYPE_ARG_TYPES (funtype
) != 0)
2359 = (list_length (TYPE_ARG_TYPES (funtype
))
2360 /* Don't include the last named arg. */
2361 - (STRICT_ARGUMENT_NAMING
? 0 : 1)
2362 /* Count the struct value address, if it is passed as a parm. */
2363 + structure_value_addr_parm
);
2365 /* If we know nothing, treat all args as named. */
2366 n_named_args
= num_actuals
;
2368 /* Start updating where the next arg would go.
2370 On some machines (such as the PA) indirect calls have a different
2371 calling convention than normal calls. The last argument in
2372 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2374 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, (fndecl
== 0));
2376 /* Make a vector to hold all the information about each arg. */
2377 args
= (struct arg_data
*) alloca (num_actuals
* sizeof (struct arg_data
));
2378 memset ((char *) args
, 0, num_actuals
* sizeof (struct arg_data
));
2380 /* Build up entries in the ARGS array, compute the size of the
2381 arguments into ARGS_SIZE, etc. */
2382 initialize_argument_information (num_actuals
, args
, &args_size
,
2383 n_named_args
, actparms
, fndecl
,
2384 &args_so_far
, reg_parm_stack_space
,
2385 &old_stack_level
, &old_pending_adj
,
2386 &must_preallocate
, &flags
);
2390 /* If this function requires a variable-sized argument list, don't
2391 try to make a cse'able block for this call. We may be able to
2392 do this eventually, but it is too complicated to keep track of
2393 what insns go in the cse'able block and which don't. */
2395 flags
&= ~ECF_LIBCALL_BLOCK
;
2396 must_preallocate
= 1;
2399 /* Now make final decision about preallocating stack space. */
2400 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2404 /* If the structure value address will reference the stack pointer, we
2405 must stabilize it. We don't need to do this if we know that we are
2406 not going to adjust the stack pointer in processing this call. */
2408 if (structure_value_addr
2409 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2410 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2411 structure_value_addr
))
2413 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2414 structure_value_addr
= copy_to_reg (structure_value_addr
);
2416 /* Tail calls can make things harder to debug, and we're traditionally
2417 pushed these optimizations into -O2. Don't try if we're already
2418 expanding a call, as that means we're an argument. Don't try if
2419 there's cleanups, as we know there's code to follow the call.
2421 If rtx_equal_function_value_matters is false, that means we've
2422 finished with regular parsing. Which means that some of the
2423 machinery we use to generate tail-calls is no longer in place.
2424 This is most often true of sjlj-exceptions, which we couldn't
2425 tail-call to anyway. */
2427 if (currently_expanding_call
++ != 0
2428 || !flag_optimize_sibling_calls
2429 || !rtx_equal_function_value_matters
2430 || any_pending_cleanups (1)
2432 try_tail_call
= try_tail_recursion
= 0;
2434 /* Tail recursion fails, when we are not dealing with recursive calls. */
2435 if (!try_tail_recursion
2436 || TREE_CODE (TREE_OPERAND (exp
, 0)) != ADDR_EXPR
2437 || TREE_OPERAND (TREE_OPERAND (exp
, 0), 0) != current_function_decl
)
2438 try_tail_recursion
= 0;
2440 /* Rest of purposes for tail call optimizations to fail. */
2442 #ifdef HAVE_sibcall_epilogue
2443 !HAVE_sibcall_epilogue
2448 /* Doing sibling call optimization needs some work, since
2449 structure_value_addr can be allocated on the stack.
2450 It does not seem worth the effort since few optimizable
2451 sibling calls will return a structure. */
2452 || structure_value_addr
!= NULL_RTX
2453 /* If the register holding the address is a callee saved
2454 register, then we lose. We have no way to prevent that,
2455 so we only allow calls to named functions. */
2456 /* ??? This could be done by having the insn constraints
2457 use a register class that is all call-clobbered. Any
2458 reload insns generated to fix things up would appear
2459 before the sibcall_epilogue. */
2460 || fndecl
== NULL_TREE
2461 || (flags
& (ECF_RETURNS_TWICE
| ECF_LONGJMP
))
2462 || TREE_THIS_VOLATILE (fndecl
)
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
,
3321 validize_mem (args
[i
].save_area
),
3322 GEN_INT (args
[i
].size
.constant
));
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 (GET_MODE (val
) == MEM
&& ! must_copy
)
3696 slot
= assign_temp ((*lang_hooks
.types
.type_for_mode
) (mode
, 0),
3698 emit_move_insn (slot
, val
);
3702 tree type
= (*lang_hooks
.types
.type_for_mode
) (mode
, 0);
3704 slot
= gen_rtx_MEM (mode
,
3705 expand_expr (build1 (ADDR_EXPR
,
3708 make_tree (type
, val
)),
3709 NULL_RTX
, VOIDmode
, 0));
3712 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3713 gen_rtx_USE (VOIDmode
, slot
),
3716 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3717 gen_rtx_CLOBBER (VOIDmode
,
3722 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3726 argvec
[count
].value
= val
;
3727 argvec
[count
].mode
= mode
;
3729 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, mode
, NULL_TREE
, 1);
3731 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3732 argvec
[count
].partial
3733 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, mode
, NULL_TREE
, 1);
3735 argvec
[count
].partial
= 0;
3738 locate_and_pad_parm (mode
, NULL_TREE
,
3739 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3742 argvec
[count
].reg
!= 0,
3744 NULL_TREE
, &args_size
, &argvec
[count
].offset
,
3745 &argvec
[count
].size
, &alignment_pad
);
3747 if (argvec
[count
].size
.var
)
3750 if (reg_parm_stack_space
== 0 && argvec
[count
].partial
)
3751 argvec
[count
].size
.constant
-= argvec
[count
].partial
* UNITS_PER_WORD
;
3753 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3754 || reg_parm_stack_space
> 0)
3755 args_size
.constant
+= argvec
[count
].size
.constant
;
3757 FUNCTION_ARG_ADVANCE (args_so_far
, mode
, (tree
) 0, 1);
3760 #ifdef FINAL_REG_PARM_STACK_SPACE
3761 reg_parm_stack_space
= FINAL_REG_PARM_STACK_SPACE (args_size
.constant
,
3764 /* If this machine requires an external definition for library
3765 functions, write one out. */
3766 assemble_external_libcall (fun
);
3768 original_args_size
= args_size
;
3769 args_size
.constant
= (((args_size
.constant
3770 + stack_pointer_delta
3774 - stack_pointer_delta
);
3776 args_size
.constant
= MAX (args_size
.constant
,
3777 reg_parm_stack_space
);
3779 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3780 args_size
.constant
-= reg_parm_stack_space
;
3783 if (args_size
.constant
> current_function_outgoing_args_size
)
3784 current_function_outgoing_args_size
= args_size
.constant
;
3786 if (ACCUMULATE_OUTGOING_ARGS
)
3788 /* Since the stack pointer will never be pushed, it is possible for
3789 the evaluation of a parm to clobber something we have already
3790 written to the stack. Since most function calls on RISC machines
3791 do not use the stack, this is uncommon, but must work correctly.
3793 Therefore, we save any area of the stack that was already written
3794 and that we are using. Here we set up to do this by making a new
3795 stack usage map from the old one.
3797 Another approach might be to try to reorder the argument
3798 evaluations to avoid this conflicting stack usage. */
3800 needed
= args_size
.constant
;
3802 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3803 /* Since we will be writing into the entire argument area, the
3804 map must be allocated for its entire size, not just the part that
3805 is the responsibility of the caller. */
3806 needed
+= reg_parm_stack_space
;
3809 #ifdef ARGS_GROW_DOWNWARD
3810 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3813 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3816 stack_usage_map
= (char *) alloca (highest_outgoing_arg_in_use
);
3818 if (initial_highest_arg_in_use
)
3819 memcpy (stack_usage_map
, initial_stack_usage_map
,
3820 initial_highest_arg_in_use
);
3822 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3823 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3824 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3827 /* We must be careful to use virtual regs before they're instantiated,
3828 and real regs afterwards. Loop optimization, for example, can create
3829 new libcalls after we've instantiated the virtual regs, and if we
3830 use virtuals anyway, they won't match the rtl patterns. */
3832 if (virtuals_instantiated
)
3833 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3835 argblock
= virtual_outgoing_args_rtx
;
3840 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3843 /* If we push args individually in reverse order, perform stack alignment
3844 before the first push (the last arg). */
3845 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3846 anti_adjust_stack (GEN_INT (args_size
.constant
3847 - original_args_size
.constant
));
3849 if (PUSH_ARGS_REVERSED
)
3860 #ifdef REG_PARM_STACK_SPACE
3861 if (ACCUMULATE_OUTGOING_ARGS
)
3863 /* The argument list is the property of the called routine and it
3864 may clobber it. If the fixed area has been used for previous
3865 parameters, we must save and restore it.
3867 Here we compute the boundary of the that needs to be saved, if any. */
3869 #ifdef ARGS_GROW_DOWNWARD
3870 for (count
= 0; count
< reg_parm_stack_space
+ 1; count
++)
3872 for (count
= 0; count
< reg_parm_stack_space
; count
++)
3875 if (count
>= highest_outgoing_arg_in_use
3876 || stack_usage_map
[count
] == 0)
3879 if (low_to_save
== -1)
3880 low_to_save
= count
;
3882 high_to_save
= count
;
3885 if (low_to_save
>= 0)
3887 int num_to_save
= high_to_save
- low_to_save
+ 1;
3888 enum machine_mode save_mode
3889 = mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
3892 /* If we don't have the required alignment, must do this in BLKmode. */
3893 if ((low_to_save
& (MIN (GET_MODE_SIZE (save_mode
),
3894 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
3895 save_mode
= BLKmode
;
3897 #ifdef ARGS_GROW_DOWNWARD
3898 stack_area
= gen_rtx_MEM (save_mode
,
3899 memory_address (save_mode
,
3900 plus_constant (argblock
,
3903 stack_area
= gen_rtx_MEM (save_mode
,
3904 memory_address (save_mode
,
3905 plus_constant (argblock
,
3908 if (save_mode
== BLKmode
)
3910 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
3911 set_mem_align (save_area
, PARM_BOUNDARY
);
3912 emit_block_move (validize_mem (save_area
), stack_area
,
3913 GEN_INT (num_to_save
));
3917 save_area
= gen_reg_rtx (save_mode
);
3918 emit_move_insn (save_area
, stack_area
);
3924 /* Push the args that need to be pushed. */
3926 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3927 are to be pushed. */
3928 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3930 enum machine_mode mode
= argvec
[argnum
].mode
;
3931 rtx val
= argvec
[argnum
].value
;
3932 rtx reg
= argvec
[argnum
].reg
;
3933 int partial
= argvec
[argnum
].partial
;
3934 int lower_bound
= 0, upper_bound
= 0, i
;
3936 if (! (reg
!= 0 && partial
== 0))
3938 if (ACCUMULATE_OUTGOING_ARGS
)
3940 /* If this is being stored into a pre-allocated, fixed-size,
3941 stack area, save any previous data at that location. */
3943 #ifdef ARGS_GROW_DOWNWARD
3944 /* stack_slot is negative, but we want to index stack_usage_map
3945 with positive values. */
3946 upper_bound
= -argvec
[argnum
].offset
.constant
+ 1;
3947 lower_bound
= upper_bound
- argvec
[argnum
].size
.constant
;
3949 lower_bound
= argvec
[argnum
].offset
.constant
;
3950 upper_bound
= lower_bound
+ argvec
[argnum
].size
.constant
;
3953 for (i
= lower_bound
; i
< upper_bound
; i
++)
3954 if (stack_usage_map
[i
]
3955 /* Don't store things in the fixed argument area at this
3956 point; it has already been saved. */
3957 && i
> reg_parm_stack_space
)
3960 if (i
!= upper_bound
)
3962 /* We need to make a save area. See what mode we can make
3964 enum machine_mode save_mode
3965 = mode_for_size (argvec
[argnum
].size
.constant
3973 plus_constant (argblock
,
3974 argvec
[argnum
].offset
.constant
)));
3975 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3977 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3981 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, 0, partial
, reg
, 0,
3982 argblock
, GEN_INT (argvec
[argnum
].offset
.constant
),
3983 reg_parm_stack_space
, ARGS_SIZE_RTX (alignment_pad
));
3985 /* Now mark the segment we just used. */
3986 if (ACCUMULATE_OUTGOING_ARGS
)
3987 for (i
= lower_bound
; i
< upper_bound
; i
++)
3988 stack_usage_map
[i
] = 1;
3994 /* If we pushed args in forward order, perform stack alignment
3995 after pushing the last arg. */
3996 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3997 anti_adjust_stack (GEN_INT (args_size
.constant
3998 - original_args_size
.constant
));
4000 if (PUSH_ARGS_REVERSED
)
4005 fun
= prepare_call_address (fun
, NULL_TREE
, &call_fusage
, 0, 0);
4007 /* Now load any reg parms into their regs. */
4009 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4010 are to be pushed. */
4011 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
4013 rtx val
= argvec
[argnum
].value
;
4014 rtx reg
= argvec
[argnum
].reg
;
4015 int partial
= argvec
[argnum
].partial
;
4017 /* Handle calls that pass values in multiple non-contiguous
4018 locations. The PA64 has examples of this for library calls. */
4019 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
4020 emit_group_load (reg
, val
, GET_MODE_SIZE (GET_MODE (val
)));
4021 else if (reg
!= 0 && partial
== 0)
4022 emit_move_insn (reg
, val
);
4027 /* Any regs containing parms remain in use through the call. */
4028 for (count
= 0; count
< nargs
; count
++)
4030 rtx reg
= argvec
[count
].reg
;
4031 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
4032 use_group_regs (&call_fusage
, reg
);
4034 use_reg (&call_fusage
, reg
);
4037 /* Pass the function the address in which to return a structure value. */
4038 if (mem_value
!= 0 && struct_value_rtx
!= 0 && ! pcc_struct_value
)
4040 emit_move_insn (struct_value_rtx
,
4042 force_operand (XEXP (mem_value
, 0),
4044 if (GET_CODE (struct_value_rtx
) == REG
)
4045 use_reg (&call_fusage
, struct_value_rtx
);
4048 /* Don't allow popping to be deferred, since then
4049 cse'ing of library calls could delete a call and leave the pop. */
4051 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
4052 ? hard_libcall_value (outmode
) : NULL_RTX
);
4054 /* Stack must be properly aligned now. */
4055 if (stack_pointer_delta
& (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1))
4058 before_call
= get_last_insn ();
4060 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4061 will set inhibit_defer_pop to that value. */
4062 /* The return type is needed to decide how many bytes the function pops.
4063 Signedness plays no role in that, so for simplicity, we pretend it's
4064 always signed. We also assume that the list of arguments passed has
4065 no impact, so we pretend it is unknown. */
4068 get_identifier (XSTR (orgfun
, 0)),
4069 build_function_type (tfom
, NULL_TREE
),
4070 original_args_size
.constant
, args_size
.constant
,
4072 FUNCTION_ARG (args_so_far
, VOIDmode
, void_type_node
, 1),
4074 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, & args_so_far
);
4076 /* For calls to `setjmp', etc., inform flow.c it should complain
4077 if nonvolatile values are live. For functions that cannot return,
4078 inform flow that control does not fall through. */
4080 if (flags
& (ECF_NORETURN
| ECF_LONGJMP
))
4082 /* The barrier note must be emitted
4083 immediately after the CALL_INSN. Some ports emit more than
4084 just a CALL_INSN above, so we must search for it here. */
4086 rtx last
= get_last_insn ();
4087 while (GET_CODE (last
) != CALL_INSN
)
4089 last
= PREV_INSN (last
);
4090 /* There was no CALL_INSN? */
4091 if (last
== before_call
)
4095 emit_barrier_after (last
);
4098 /* Now restore inhibit_defer_pop to its actual original value. */
4101 /* If call is cse'able, make appropriate pair of reg-notes around it.
4102 Test valreg so we don't crash; may safely ignore `const'
4103 if return type is void. Disable for PARALLEL return values, because
4104 we have no way to move such values into a pseudo register. */
4105 if (flags
& ECF_LIBCALL_BLOCK
)
4109 if (valreg
== 0 || GET_CODE (valreg
) == PARALLEL
)
4111 insns
= get_insns ();
4118 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
4121 /* Construct an "equal form" for the value which mentions all the
4122 arguments in order as well as the function name. */
4123 for (i
= 0; i
< nargs
; i
++)
4124 note
= gen_rtx_EXPR_LIST (VOIDmode
, argvec
[i
].value
, note
);
4125 note
= gen_rtx_EXPR_LIST (VOIDmode
, fun
, note
);
4127 insns
= get_insns ();
4130 if (flags
& ECF_PURE
)
4131 note
= gen_rtx_EXPR_LIST (VOIDmode
,
4132 gen_rtx_USE (VOIDmode
,
4133 gen_rtx_MEM (BLKmode
,
4134 gen_rtx_SCRATCH (VOIDmode
))),
4137 emit_libcall_block (insns
, temp
, valreg
, note
);
4144 /* Copy the value to the right place. */
4145 if (outmode
!= VOIDmode
&& retval
)
4151 if (value
!= mem_value
)
4152 emit_move_insn (value
, mem_value
);
4154 else if (value
!= 0)
4155 emit_move_insn (value
, hard_libcall_value (outmode
));
4157 value
= hard_libcall_value (outmode
);
4160 if (ACCUMULATE_OUTGOING_ARGS
)
4162 #ifdef REG_PARM_STACK_SPACE
4165 enum machine_mode save_mode
= GET_MODE (save_area
);
4166 #ifdef ARGS_GROW_DOWNWARD
4168 = gen_rtx_MEM (save_mode
,
4169 memory_address (save_mode
,
4170 plus_constant (argblock
,
4174 = gen_rtx_MEM (save_mode
,
4175 memory_address (save_mode
,
4176 plus_constant (argblock
, low_to_save
)));
4179 set_mem_align (stack_area
, PARM_BOUNDARY
);
4180 if (save_mode
!= BLKmode
)
4181 emit_move_insn (stack_area
, save_area
);
4183 emit_block_move (stack_area
, validize_mem (save_area
),
4184 GEN_INT (high_to_save
- low_to_save
+ 1));
4188 /* If we saved any argument areas, restore them. */
4189 for (count
= 0; count
< nargs
; count
++)
4190 if (argvec
[count
].save_area
)
4192 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
4194 = gen_rtx_MEM (save_mode
,
4197 plus_constant (argblock
,
4198 argvec
[count
].offset
.constant
)));
4200 emit_move_insn (stack_area
, argvec
[count
].save_area
);
4203 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4204 stack_usage_map
= initial_stack_usage_map
;
4211 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4212 (emitting the queue unless NO_QUEUE is nonzero),
4213 for a value of mode OUTMODE,
4214 with NARGS different arguments, passed as alternating rtx values
4215 and machine_modes to convert them to.
4216 The rtx values should have been passed through protect_from_queue already.
4218 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4219 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4220 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4221 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4222 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4223 or other LCT_ value for other types of library calls. */
4226 emit_library_call
VPARAMS((rtx orgfun
, enum libcall_type fn_type
,
4227 enum machine_mode outmode
, int nargs
, ...))
4230 VA_FIXEDARG (p
, rtx
, orgfun
);
4231 VA_FIXEDARG (p
, int, fn_type
);
4232 VA_FIXEDARG (p
, enum machine_mode
, outmode
);
4233 VA_FIXEDARG (p
, int, nargs
);
4235 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
4240 /* Like emit_library_call except that an extra argument, VALUE,
4241 comes second and says where to store the result.
4242 (If VALUE is zero, this function chooses a convenient way
4243 to return the value.
4245 This function returns an rtx for where the value is to be found.
4246 If VALUE is nonzero, VALUE is returned. */
4249 emit_library_call_value
VPARAMS((rtx orgfun
, rtx value
,
4250 enum libcall_type fn_type
,
4251 enum machine_mode outmode
, int nargs
, ...))
4256 VA_FIXEDARG (p
, rtx
, orgfun
);
4257 VA_FIXEDARG (p
, rtx
, value
);
4258 VA_FIXEDARG (p
, int, fn_type
);
4259 VA_FIXEDARG (p
, enum machine_mode
, outmode
);
4260 VA_FIXEDARG (p
, int, nargs
);
4262 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
4270 /* Store a single argument for a function call
4271 into the register or memory area where it must be passed.
4272 *ARG describes the argument value and where to pass it.
4274 ARGBLOCK is the address of the stack-block for all the arguments,
4275 or 0 on a machine where arguments are pushed individually.
4277 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4278 so must be careful about how the stack is used.
4280 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4281 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4282 that we need not worry about saving and restoring the stack.
4284 FNDECL is the declaration of the function we are calling.
4286 Return non-zero if this arg should cause sibcall failure,
4290 store_one_arg (arg
, argblock
, flags
, variable_size
, reg_parm_stack_space
)
4291 struct arg_data
*arg
;
4294 int variable_size ATTRIBUTE_UNUSED
;
4295 int reg_parm_stack_space
;
4297 tree pval
= arg
->tree_value
;
4301 int i
, lower_bound
= 0, upper_bound
= 0;
4302 int sibcall_failure
= 0;
4304 if (TREE_CODE (pval
) == ERROR_MARK
)
4307 /* Push a new temporary level for any temporaries we make for
4311 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4313 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4314 save any previous data at that location. */
4315 if (argblock
&& ! variable_size
&& arg
->stack
)
4317 #ifdef ARGS_GROW_DOWNWARD
4318 /* stack_slot is negative, but we want to index stack_usage_map
4319 with positive values. */
4320 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4321 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4325 lower_bound
= upper_bound
- arg
->size
.constant
;
4327 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4328 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4332 upper_bound
= lower_bound
+ arg
->size
.constant
;
4335 for (i
= lower_bound
; i
< upper_bound
; i
++)
4336 if (stack_usage_map
[i
]
4337 /* Don't store things in the fixed argument area at this point;
4338 it has already been saved. */
4339 && i
> reg_parm_stack_space
)
4342 if (i
!= upper_bound
)
4344 /* We need to make a save area. See what mode we can make it. */
4345 enum machine_mode save_mode
4346 = mode_for_size (arg
->size
.constant
* BITS_PER_UNIT
, MODE_INT
, 1);
4348 = gen_rtx_MEM (save_mode
,
4349 memory_address (save_mode
,
4350 XEXP (arg
->stack_slot
, 0)));
4352 if (save_mode
== BLKmode
)
4354 tree ot
= TREE_TYPE (arg
->tree_value
);
4355 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4356 | TYPE_QUAL_CONST
));
4358 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4359 preserve_temp_slots (arg
->save_area
);
4360 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4361 expr_size (arg
->tree_value
));
4365 arg
->save_area
= gen_reg_rtx (save_mode
);
4366 emit_move_insn (arg
->save_area
, stack_area
);
4370 /* Now that we have saved any slots that will be overwritten by this
4371 store, mark all slots this store will use. We must do this before
4372 we actually expand the argument since the expansion itself may
4373 trigger library calls which might need to use the same stack slot. */
4374 if (argblock
&& ! variable_size
&& arg
->stack
)
4375 for (i
= lower_bound
; i
< upper_bound
; i
++)
4376 stack_usage_map
[i
] = 1;
4379 /* If this isn't going to be placed on both the stack and in registers,
4380 set up the register and number of words. */
4381 if (! arg
->pass_on_stack
)
4383 if (flags
& ECF_SIBCALL
)
4384 reg
= arg
->tail_call_reg
;
4387 partial
= arg
->partial
;
4390 if (reg
!= 0 && partial
== 0)
4391 /* Being passed entirely in a register. We shouldn't be called in
4395 /* If this arg needs special alignment, don't load the registers
4397 if (arg
->n_aligned_regs
!= 0)
4400 /* If this is being passed partially in a register, we can't evaluate
4401 it directly into its stack slot. Otherwise, we can. */
4402 if (arg
->value
== 0)
4404 /* stack_arg_under_construction is nonzero if a function argument is
4405 being evaluated directly into the outgoing argument list and
4406 expand_call must take special action to preserve the argument list
4407 if it is called recursively.
4409 For scalar function arguments stack_usage_map is sufficient to
4410 determine which stack slots must be saved and restored. Scalar
4411 arguments in general have pass_on_stack == 0.
4413 If this argument is initialized by a function which takes the
4414 address of the argument (a C++ constructor or a C function
4415 returning a BLKmode structure), then stack_usage_map is
4416 insufficient and expand_call must push the stack around the
4417 function call. Such arguments have pass_on_stack == 1.
4419 Note that it is always safe to set stack_arg_under_construction,
4420 but this generates suboptimal code if set when not needed. */
4422 if (arg
->pass_on_stack
)
4423 stack_arg_under_construction
++;
4425 arg
->value
= expand_expr (pval
,
4427 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4428 ? NULL_RTX
: arg
->stack
,
4431 /* If we are promoting object (or for any other reason) the mode
4432 doesn't agree, convert the mode. */
4434 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4435 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4436 arg
->value
, arg
->unsignedp
);
4438 if (arg
->pass_on_stack
)
4439 stack_arg_under_construction
--;
4442 /* Don't allow anything left on stack from computation
4443 of argument to alloca. */
4444 if (flags
& ECF_MAY_BE_ALLOCA
)
4445 do_pending_stack_adjust ();
4447 if (arg
->value
== arg
->stack
)
4448 /* If the value is already in the stack slot, we are done. */
4450 else if (arg
->mode
!= BLKmode
)
4454 /* Argument is a scalar, not entirely passed in registers.
4455 (If part is passed in registers, arg->partial says how much
4456 and emit_push_insn will take care of putting it there.)
4458 Push it, and if its size is less than the
4459 amount of space allocated to it,
4460 also bump stack pointer by the additional space.
4461 Note that in C the default argument promotions
4462 will prevent such mismatches. */
4464 size
= GET_MODE_SIZE (arg
->mode
);
4465 /* Compute how much space the push instruction will push.
4466 On many machines, pushing a byte will advance the stack
4467 pointer by a halfword. */
4468 #ifdef PUSH_ROUNDING
4469 size
= PUSH_ROUNDING (size
);
4473 /* Compute how much space the argument should get:
4474 round up to a multiple of the alignment for arguments. */
4475 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4476 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4477 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4478 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4480 /* This isn't already where we want it on the stack, so put it there.
4481 This can either be done with push or copy insns. */
4482 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
, 0,
4483 partial
, reg
, used
- size
, argblock
,
4484 ARGS_SIZE_RTX (arg
->offset
), reg_parm_stack_space
,
4485 ARGS_SIZE_RTX (arg
->alignment_pad
));
4487 /* Unless this is a partially-in-register argument, the argument is now
4490 arg
->value
= arg
->stack
;
4494 /* BLKmode, at least partly to be pushed. */
4499 /* Pushing a nonscalar.
4500 If part is passed in registers, PARTIAL says how much
4501 and emit_push_insn will take care of putting it there. */
4503 /* Round its size up to a multiple
4504 of the allocation unit for arguments. */
4506 if (arg
->size
.var
!= 0)
4509 size_rtx
= ARGS_SIZE_RTX (arg
->size
);
4513 /* PUSH_ROUNDING has no effect on us, because
4514 emit_push_insn for BLKmode is careful to avoid it. */
4515 excess
= (arg
->size
.constant
- int_size_in_bytes (TREE_TYPE (pval
))
4516 + partial
* UNITS_PER_WORD
);
4517 size_rtx
= expr_size (pval
);
4520 if ((flags
& ECF_SIBCALL
) && GET_CODE (arg
->value
) == MEM
)
4522 /* emit_push_insn might not work properly if arg->value and
4523 argblock + arg->offset areas overlap. */
4527 if (XEXP (x
, 0) == current_function_internal_arg_pointer
4528 || (GET_CODE (XEXP (x
, 0)) == PLUS
4529 && XEXP (XEXP (x
, 0), 0) ==
4530 current_function_internal_arg_pointer
4531 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
))
4533 if (XEXP (x
, 0) != current_function_internal_arg_pointer
)
4534 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4536 /* expand_call should ensure this */
4537 if (arg
->offset
.var
|| GET_CODE (size_rtx
) != CONST_INT
)
4540 if (arg
->offset
.constant
> i
)
4542 if (arg
->offset
.constant
< i
+ INTVAL (size_rtx
))
4543 sibcall_failure
= 1;
4545 else if (arg
->offset
.constant
< i
)
4547 if (i
< arg
->offset
.constant
+ INTVAL (size_rtx
))
4548 sibcall_failure
= 1;
4553 /* Special handling is required if part of the parameter lies in the
4554 register parameter area. The argument may be copied into the stack
4555 slot using memcpy(), but the original contents of the register
4556 parameter area will be restored after the memcpy() call.
4558 To ensure that the part that lies in the register parameter area
4559 is copied correctly, we emit a separate push for that part. This
4560 push should be small enough to avoid a call to memcpy(). */
4561 #ifndef STACK_PARMS_IN_REG_PARM_AREA
4562 if (arg
->reg
&& arg
->pass_on_stack
)
4567 if (arg
->offset
.constant
< reg_parm_stack_space
&& arg
->offset
.var
)
4568 error ("variable offset is passed partially in stack and in reg");
4569 else if (arg
->offset
.constant
< reg_parm_stack_space
&& arg
->size
.var
)
4570 error ("variable size is passed partially in stack and in reg");
4571 else if (arg
->offset
.constant
< reg_parm_stack_space
4572 && ((arg
->offset
.constant
+ arg
->size
.constant
)
4573 > reg_parm_stack_space
))
4575 rtx size_rtx1
= GEN_INT (reg_parm_stack_space
- arg
->offset
.constant
);
4576 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx1
,
4577 TYPE_ALIGN (TREE_TYPE (pval
)), partial
, reg
,
4578 excess
, argblock
, ARGS_SIZE_RTX (arg
->offset
),
4579 reg_parm_stack_space
,
4580 ARGS_SIZE_RTX (arg
->alignment_pad
));
4585 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4586 TYPE_ALIGN (TREE_TYPE (pval
)), partial
, reg
, excess
,
4587 argblock
, ARGS_SIZE_RTX (arg
->offset
),
4588 reg_parm_stack_space
,
4589 ARGS_SIZE_RTX (arg
->alignment_pad
));
4591 /* Unless this is a partially-in-register argument, the argument is now
4594 ??? Unlike the case above, in which we want the actual
4595 address of the data, so that we can load it directly into a
4596 register, here we want the address of the stack slot, so that
4597 it's properly aligned for word-by-word copying or something
4598 like that. It's not clear that this is always correct. */
4600 arg
->value
= arg
->stack_slot
;
4603 /* Once we have pushed something, pops can't safely
4604 be deferred during the rest of the arguments. */
4607 /* ANSI doesn't require a sequence point here,
4608 but PCC has one, so this will avoid some problems. */
4611 /* Free any temporary slots made in processing this argument. Show
4612 that we might have taken the address of something and pushed that
4614 preserve_temp_slots (NULL_RTX
);
4618 return sibcall_failure
;