1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998
3 1999, 2000, 2001 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
36 #include "langhooks.h"
39 #if !defined FUNCTION_OK_FOR_SIBCALL
40 #define FUNCTION_OK_FOR_SIBCALL(DECL) 1
43 /* Decide whether a function's arguments should be processed
44 from first to last or from last to first.
46 They should if the stack and args grow in opposite directions, but
47 only if we have push insns. */
51 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
52 #define PUSH_ARGS_REVERSED PUSH_ARGS
57 #ifndef PUSH_ARGS_REVERSED
58 #define PUSH_ARGS_REVERSED 0
61 #ifndef STACK_POINTER_OFFSET
62 #define STACK_POINTER_OFFSET 0
65 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
66 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
68 /* Data structure and subroutines used within expand_call. */
72 /* Tree node for this argument. */
74 /* Mode for value; TYPE_MODE unless promoted. */
75 enum machine_mode mode
;
76 /* Current RTL value for argument, or 0 if it isn't precomputed. */
78 /* Initially-compute RTL value for argument; only for const functions. */
80 /* Register to pass this argument in, 0 if passed on stack, or an
81 PARALLEL if the arg is to be copied into multiple non-contiguous
84 /* Register to pass this argument in when generating tail call sequence.
85 This is not the same register as for normal calls on machines with
88 /* If REG was promoted from the actual mode of the argument expression,
89 indicates whether the promotion is sign- or zero-extended. */
91 /* Number of registers to use. 0 means put the whole arg in registers.
92 Also 0 if not passed in registers. */
94 /* Nonzero if argument must be passed on stack.
95 Note that some arguments may be passed on the stack
96 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
97 pass_on_stack identifies arguments that *cannot* go in registers. */
99 /* Offset of this argument from beginning of stack-args. */
100 struct args_size offset
;
101 /* Similar, but offset to the start of the stack slot. Different from
102 OFFSET if this arg pads downward. */
103 struct args_size slot_offset
;
104 /* Size of this argument on the stack, rounded up for any padding it gets,
105 parts of the argument passed in registers do not count.
106 If REG_PARM_STACK_SPACE is defined, then register parms
107 are counted here as well. */
108 struct args_size size
;
109 /* Location on the stack at which parameter should be stored. The store
110 has already been done if STACK == VALUE. */
112 /* Location on the stack of the start of this argument slot. This can
113 differ from STACK if this arg pads downward. This location is known
114 to be aligned to FUNCTION_ARG_BOUNDARY. */
116 /* Place that this stack area has been saved, if needed. */
118 /* If an argument's alignment does not permit direct copying into registers,
119 copy in smaller-sized pieces into pseudos. These are stored in a
120 block pointed to by this field. The next field says how many
121 word-sized pseudos we made. */
124 /* The amount that the stack pointer needs to be adjusted to
125 force alignment for the next argument. */
126 struct args_size alignment_pad
;
129 /* A vector of one char per byte of stack space. A byte if nonzero if
130 the corresponding stack location has been used.
131 This vector is used to prevent a function call within an argument from
132 clobbering any stack already set up. */
133 static char *stack_usage_map
;
135 /* Size of STACK_USAGE_MAP. */
136 static int highest_outgoing_arg_in_use
;
138 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
139 stack location's tail call argument has been already stored into the stack.
140 This bitmap is used to prevent sibling call optimization if function tries
141 to use parent's incoming argument slots when they have been already
142 overwritten with tail call arguments. */
143 static sbitmap stored_args_map
;
145 /* stack_arg_under_construction is nonzero when an argument may be
146 initialized with a constructor call (including a C function that
147 returns a BLKmode struct) and expand_call must take special action
148 to make sure the object being constructed does not overlap the
149 argument list for the constructor call. */
150 int stack_arg_under_construction
;
152 static int calls_function
PARAMS ((tree
, int));
153 static int calls_function_1
PARAMS ((tree
, int));
155 /* Nonzero if this is a call to a `const' function. */
157 /* Nonzero if this is a call to a `volatile' function. */
158 #define ECF_NORETURN 2
159 /* Nonzero if this is a call to malloc or a related function. */
161 /* Nonzero if it is plausible that this is a call to alloca. */
162 #define ECF_MAY_BE_ALLOCA 8
163 /* Nonzero if this is a call to a function that won't throw an exception. */
164 #define ECF_NOTHROW 16
165 /* Nonzero if this is a call to setjmp or a related function. */
166 #define ECF_RETURNS_TWICE 32
167 /* Nonzero if this is a call to `longjmp'. */
168 #define ECF_LONGJMP 64
169 /* Nonzero if this is a syscall that makes a new process in the image of
171 #define ECF_FORK_OR_EXEC 128
172 #define ECF_SIBCALL 256
173 /* Nonzero if this is a call to "pure" function (like const function,
174 but may read memory. */
176 /* Nonzero if this is a call to a function that returns with the stack
177 pointer depressed. */
178 #define ECF_SP_DEPRESSED 1024
179 /* Nonzero if this call is known to always return. */
180 #define ECF_ALWAYS_RETURN 2048
181 /* Create libcall block around the call. */
182 #define ECF_LIBCALL_BLOCK 4096
184 static void emit_call_1
PARAMS ((rtx
, tree
, tree
, HOST_WIDE_INT
,
185 HOST_WIDE_INT
, HOST_WIDE_INT
, rtx
,
188 static void precompute_register_parameters
PARAMS ((int,
191 static int store_one_arg
PARAMS ((struct arg_data
*, rtx
, int, int,
193 static void store_unaligned_arguments_into_pseudos
PARAMS ((struct arg_data
*,
195 static int finalize_must_preallocate
PARAMS ((int, int,
197 struct args_size
*));
198 static void precompute_arguments
PARAMS ((int, int,
200 static int compute_argument_block_size
PARAMS ((int,
203 static void initialize_argument_information
PARAMS ((int,
210 static void compute_argument_addresses
PARAMS ((struct arg_data
*,
212 static rtx rtx_for_function_call
PARAMS ((tree
, tree
));
213 static void load_register_parameters
PARAMS ((struct arg_data
*,
215 static rtx emit_library_call_value_1
PARAMS ((int, rtx
, rtx
,
219 static int special_function_p
PARAMS ((tree
, int));
220 static int flags_from_decl_or_type
PARAMS ((tree
));
221 static rtx try_to_integrate
PARAMS ((tree
, tree
, rtx
,
223 static int check_sibcall_argument_overlap_1
PARAMS ((rtx
));
224 static int check_sibcall_argument_overlap
PARAMS ((rtx
, struct arg_data
*));
226 static int combine_pending_stack_adjustment_and_call
227 PARAMS ((int, struct args_size
*, int));
229 #ifdef REG_PARM_STACK_SPACE
230 static rtx save_fixed_argument_area
PARAMS ((int, rtx
, int *, int *));
231 static void restore_fixed_argument_area
PARAMS ((rtx
, rtx
, int, int));
234 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
237 If WHICH is 0, return 1 if EXP contains a call to any function.
238 Actually, we only need return 1 if evaluating EXP would require pushing
239 arguments on the stack, but that is too difficult to compute, so we just
240 assume any function call might require the stack. */
242 static tree calls_function_save_exprs
;
245 calls_function (exp
, which
)
251 calls_function_save_exprs
= 0;
252 val
= calls_function_1 (exp
, which
);
253 calls_function_save_exprs
= 0;
257 /* Recursive function to do the work of above function. */
260 calls_function_1 (exp
, which
)
265 enum tree_code code
= TREE_CODE (exp
);
266 int class = TREE_CODE_CLASS (code
);
267 int length
= first_rtl_op (code
);
269 /* If this code is language-specific, we don't know what it will do. */
270 if ((int) code
>= NUM_TREE_CODES
)
278 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp
, 0))))
280 && (TYPE_RETURNS_STACK_DEPRESSED
281 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp
, 0))))))
283 else if (TREE_CODE (TREE_OPERAND (exp
, 0)) == ADDR_EXPR
284 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0))
286 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0),
288 & ECF_MAY_BE_ALLOCA
))
297 for (tem
= CONSTRUCTOR_ELTS (exp
); tem
!= 0; tem
= TREE_CHAIN (tem
))
298 if (calls_function_1 (TREE_VALUE (tem
), which
))
305 if (SAVE_EXPR_RTL (exp
) != 0)
307 if (value_member (exp
, calls_function_save_exprs
))
309 calls_function_save_exprs
= tree_cons (NULL_TREE
, exp
,
310 calls_function_save_exprs
);
311 return (TREE_OPERAND (exp
, 0) != 0
312 && calls_function_1 (TREE_OPERAND (exp
, 0), which
));
319 for (local
= BLOCK_VARS (exp
); local
; local
= TREE_CHAIN (local
))
320 if (DECL_INITIAL (local
) != 0
321 && calls_function_1 (DECL_INITIAL (local
), which
))
324 for (subblock
= BLOCK_SUBBLOCKS (exp
);
326 subblock
= TREE_CHAIN (subblock
))
327 if (calls_function_1 (subblock
, which
))
333 for (; exp
!= 0; exp
= TREE_CHAIN (exp
))
334 if (calls_function_1 (TREE_VALUE (exp
), which
))
342 /* Only expressions, references, and blocks can contain calls. */
343 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
346 for (i
= 0; i
< length
; i
++)
347 if (TREE_OPERAND (exp
, i
) != 0
348 && calls_function_1 (TREE_OPERAND (exp
, i
), which
))
354 /* Force FUNEXP into a form suitable for the address of a CALL,
355 and return that as an rtx. Also load the static chain register
356 if FNDECL is a nested function.
358 CALL_FUSAGE points to a variable holding the prospective
359 CALL_INSN_FUNCTION_USAGE information. */
362 prepare_call_address (funexp
, fndecl
, call_fusage
, reg_parm_seen
, sibcallp
)
369 rtx static_chain_value
= 0;
371 funexp
= protect_from_queue (funexp
, 0);
374 /* Get possible static chain value for nested function in C. */
375 static_chain_value
= lookup_static_chain (fndecl
);
377 /* Make a valid memory address and copy constants thru pseudo-regs,
378 but not for a constant address if -fno-function-cse. */
379 if (GET_CODE (funexp
) != SYMBOL_REF
)
380 /* If we are using registers for parameters, force the
381 function address into a register now. */
382 funexp
= ((SMALL_REGISTER_CLASSES
&& reg_parm_seen
)
383 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
384 : memory_address (FUNCTION_MODE
, funexp
));
387 #ifndef NO_FUNCTION_CSE
388 if (optimize
&& ! flag_no_function_cse
)
389 #ifdef NO_RECURSIVE_FUNCTION_CSE
390 if (fndecl
!= current_function_decl
)
392 funexp
= force_reg (Pmode
, funexp
);
396 if (static_chain_value
!= 0)
398 emit_move_insn (static_chain_rtx
, static_chain_value
);
400 if (GET_CODE (static_chain_rtx
) == REG
)
401 use_reg (call_fusage
, static_chain_rtx
);
407 /* Generate instructions to call function FUNEXP,
408 and optionally pop the results.
409 The CALL_INSN is the first insn generated.
411 FNDECL is the declaration node of the function. This is given to the
412 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
414 FUNTYPE is the data type of the function. This is given to the macro
415 RETURN_POPS_ARGS to determine whether this function pops its own args.
416 We used to allow an identifier for library functions, but that doesn't
417 work when the return type is an aggregate type and the calling convention
418 says that the pointer to this aggregate is to be popped by the callee.
420 STACK_SIZE is the number of bytes of arguments on the stack,
421 ROUNDED_STACK_SIZE is that number rounded up to
422 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
423 both to put into the call insn and to generate explicit popping
426 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
427 It is zero if this call doesn't want a structure value.
429 NEXT_ARG_REG is the rtx that results from executing
430 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
431 just after all the args have had their registers assigned.
432 This could be whatever you like, but normally it is the first
433 arg-register beyond those used for args in this call,
434 or 0 if all the arg-registers are used in this call.
435 It is passed on to `gen_call' so you can put this info in the call insn.
437 VALREG is a hard register in which a value is returned,
438 or 0 if the call does not return a value.
440 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
441 the args to this call were processed.
442 We restore `inhibit_defer_pop' to that value.
444 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
445 denote registers used by the called function. */
448 emit_call_1 (funexp
, fndecl
, funtype
, stack_size
, rounded_stack_size
,
449 struct_value_size
, next_arg_reg
, valreg
, old_inhibit_defer_pop
,
450 call_fusage
, ecf_flags
, args_so_far
)
452 tree fndecl ATTRIBUTE_UNUSED
;
453 tree funtype ATTRIBUTE_UNUSED
;
454 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED
;
455 HOST_WIDE_INT rounded_stack_size
;
456 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED
;
457 rtx next_arg_reg ATTRIBUTE_UNUSED
;
459 int old_inhibit_defer_pop
;
462 CUMULATIVE_ARGS
*args_so_far ATTRIBUTE_UNUSED
;
464 rtx rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
466 int already_popped
= 0;
467 HOST_WIDE_INT n_popped
= RETURN_POPS_ARGS (fndecl
, funtype
, stack_size
);
468 #if defined (HAVE_call) && defined (HAVE_call_value)
469 rtx struct_value_size_rtx
;
470 struct_value_size_rtx
= GEN_INT (struct_value_size
);
473 #ifdef CALL_POPS_ARGS
474 n_popped
+= CALL_POPS_ARGS (* args_so_far
);
477 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
478 and we don't want to load it into a register as an optimization,
479 because prepare_call_address already did it if it should be done. */
480 if (GET_CODE (funexp
) != SYMBOL_REF
)
481 funexp
= memory_address (FUNCTION_MODE
, funexp
);
483 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
484 if ((ecf_flags
& ECF_SIBCALL
)
485 && HAVE_sibcall_pop
&& HAVE_sibcall_value_pop
486 && (n_popped
> 0 || stack_size
== 0))
488 rtx n_pop
= GEN_INT (n_popped
);
491 /* If this subroutine pops its own args, record that in the call insn
492 if possible, for the sake of frame pointer elimination. */
495 pat
= GEN_SIBCALL_VALUE_POP (valreg
,
496 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
497 rounded_stack_size_rtx
, next_arg_reg
,
500 pat
= GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
501 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
503 emit_call_insn (pat
);
509 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
510 /* If the target has "call" or "call_value" insns, then prefer them
511 if no arguments are actually popped. If the target does not have
512 "call" or "call_value" insns, then we must use the popping versions
513 even if the call has no arguments to pop. */
514 #if defined (HAVE_call) && defined (HAVE_call_value)
515 if (HAVE_call
&& HAVE_call_value
&& HAVE_call_pop
&& HAVE_call_value_pop
516 && n_popped
> 0 && ! (ecf_flags
& ECF_SP_DEPRESSED
))
518 if (HAVE_call_pop
&& HAVE_call_value_pop
)
521 rtx n_pop
= GEN_INT (n_popped
);
524 /* If this subroutine pops its own args, record that in the call insn
525 if possible, for the sake of frame pointer elimination. */
528 pat
= GEN_CALL_VALUE_POP (valreg
,
529 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
530 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
532 pat
= GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
533 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
535 emit_call_insn (pat
);
541 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
542 if ((ecf_flags
& ECF_SIBCALL
)
543 && HAVE_sibcall
&& HAVE_sibcall_value
)
546 emit_call_insn (GEN_SIBCALL_VALUE (valreg
,
547 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
548 rounded_stack_size_rtx
,
549 next_arg_reg
, NULL_RTX
));
551 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
552 rounded_stack_size_rtx
, next_arg_reg
,
553 struct_value_size_rtx
));
558 #if defined (HAVE_call) && defined (HAVE_call_value)
559 if (HAVE_call
&& HAVE_call_value
)
562 emit_call_insn (GEN_CALL_VALUE (valreg
,
563 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
564 rounded_stack_size_rtx
, next_arg_reg
,
567 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
568 rounded_stack_size_rtx
, next_arg_reg
,
569 struct_value_size_rtx
));
575 /* Find the CALL insn we just emitted. */
576 for (call_insn
= get_last_insn ();
577 call_insn
&& GET_CODE (call_insn
) != CALL_INSN
;
578 call_insn
= PREV_INSN (call_insn
))
584 /* Mark memory as used for "pure" function call. */
585 if (ecf_flags
& ECF_PURE
)
589 gen_rtx_USE (VOIDmode
,
590 gen_rtx_MEM (BLKmode
, gen_rtx_SCRATCH (VOIDmode
))),
593 /* Put the register usage information on the CALL. If there is already
594 some usage information, put ours at the end. */
595 if (CALL_INSN_FUNCTION_USAGE (call_insn
))
599 for (link
= CALL_INSN_FUNCTION_USAGE (call_insn
); XEXP (link
, 1) != 0;
600 link
= XEXP (link
, 1))
603 XEXP (link
, 1) = call_fusage
;
606 CALL_INSN_FUNCTION_USAGE (call_insn
) = call_fusage
;
608 /* If this is a const call, then set the insn's unchanging bit. */
609 if (ecf_flags
& (ECF_CONST
| ECF_PURE
))
610 CONST_OR_PURE_CALL_P (call_insn
) = 1;
612 /* If this call can't throw, attach a REG_EH_REGION reg note to that
614 if (ecf_flags
& ECF_NOTHROW
)
615 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_EH_REGION
, const0_rtx
,
616 REG_NOTES (call_insn
));
618 if (ecf_flags
& ECF_NORETURN
)
619 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_NORETURN
, const0_rtx
,
620 REG_NOTES (call_insn
));
621 if (ecf_flags
& ECF_ALWAYS_RETURN
)
622 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN
, const0_rtx
,
623 REG_NOTES (call_insn
));
625 if (ecf_flags
& ECF_RETURNS_TWICE
)
627 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_SETJMP
, const0_rtx
,
628 REG_NOTES (call_insn
));
629 current_function_calls_setjmp
= 1;
632 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
634 /* Restore this now, so that we do defer pops for this call's args
635 if the context of the call as a whole permits. */
636 inhibit_defer_pop
= old_inhibit_defer_pop
;
641 CALL_INSN_FUNCTION_USAGE (call_insn
)
642 = gen_rtx_EXPR_LIST (VOIDmode
,
643 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
644 CALL_INSN_FUNCTION_USAGE (call_insn
));
645 rounded_stack_size
-= n_popped
;
646 rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
647 stack_pointer_delta
-= n_popped
;
650 if (!ACCUMULATE_OUTGOING_ARGS
)
652 /* If returning from the subroutine does not automatically pop the args,
653 we need an instruction to pop them sooner or later.
654 Perhaps do it now; perhaps just record how much space to pop later.
656 If returning from the subroutine does pop the args, indicate that the
657 stack pointer will be changed. */
659 if (rounded_stack_size
!= 0)
661 if (ecf_flags
& ECF_SP_DEPRESSED
)
662 /* Just pretend we did the pop. */
663 stack_pointer_delta
-= rounded_stack_size
;
664 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
665 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
666 pending_stack_adjust
+= rounded_stack_size
;
668 adjust_stack (rounded_stack_size_rtx
);
671 /* When we accumulate outgoing args, we must avoid any stack manipulations.
672 Restore the stack pointer to its original value now. Usually
673 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
674 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
675 popping variants of functions exist as well.
677 ??? We may optimize similar to defer_pop above, but it is
678 probably not worthwhile.
680 ??? It will be worthwhile to enable combine_stack_adjustments even for
683 anti_adjust_stack (GEN_INT (n_popped
));
686 /* Determine if the function identified by NAME and FNDECL is one with
687 special properties we wish to know about.
689 For example, if the function might return more than one time (setjmp), then
690 set RETURNS_TWICE to a nonzero value.
692 Similarly set LONGJMP for if the function is in the longjmp family.
694 Set MALLOC for any of the standard memory allocation functions which
695 allocate from the heap.
697 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
698 space from the stack such as alloca. */
701 special_function_p (fndecl
, flags
)
705 if (! (flags
& ECF_MALLOC
)
706 && fndecl
&& DECL_NAME (fndecl
)
707 && IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) <= 17
708 /* Exclude functions not at the file scope, or not `extern',
709 since they are not the magic functions we would otherwise
711 && DECL_CONTEXT (fndecl
) == NULL_TREE
&& TREE_PUBLIC (fndecl
))
713 const char *name
= IDENTIFIER_POINTER (DECL_NAME (fndecl
));
714 const char *tname
= name
;
716 /* We assume that alloca will always be called by name. It
717 makes no sense to pass it as a pointer-to-function to
718 anything that does not understand its behavior. */
719 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 6
721 && ! strcmp (name
, "alloca"))
722 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 16
724 && ! strcmp (name
, "__builtin_alloca"))))
725 flags
|= ECF_MAY_BE_ALLOCA
;
727 /* Disregard prefix _, __ or __x. */
730 if (name
[1] == '_' && name
[2] == 'x')
732 else if (name
[1] == '_')
741 && (! strcmp (tname
, "setjmp")
742 || ! strcmp (tname
, "setjmp_syscall")))
744 && ! strcmp (tname
, "sigsetjmp"))
746 && ! strcmp (tname
, "savectx")))
747 flags
|= ECF_RETURNS_TWICE
;
750 && ! strcmp (tname
, "siglongjmp"))
751 flags
|= ECF_LONGJMP
;
753 else if ((tname
[0] == 'q' && tname
[1] == 's'
754 && ! strcmp (tname
, "qsetjmp"))
755 || (tname
[0] == 'v' && tname
[1] == 'f'
756 && ! strcmp (tname
, "vfork")))
757 flags
|= ECF_RETURNS_TWICE
;
759 else if (tname
[0] == 'l' && tname
[1] == 'o'
760 && ! strcmp (tname
, "longjmp"))
761 flags
|= ECF_LONGJMP
;
763 else if ((tname
[0] == 'f' && tname
[1] == 'o'
764 && ! strcmp (tname
, "fork"))
765 /* Linux specific: __clone. check NAME to insist on the
766 leading underscores, to avoid polluting the ISO / POSIX
768 || (name
[0] == '_' && name
[1] == '_'
769 && ! strcmp (tname
, "clone"))
770 || (tname
[0] == 'e' && tname
[1] == 'x' && tname
[2] == 'e'
771 && tname
[3] == 'c' && (tname
[4] == 'l' || tname
[4] == 'v')
773 || ((tname
[5] == 'p' || tname
[5] == 'e')
774 && tname
[6] == '\0'))))
775 flags
|= ECF_FORK_OR_EXEC
;
777 /* Do not add any more malloc-like functions to this list,
778 instead mark them as malloc functions using the malloc attribute.
779 Note, realloc is not suitable for attribute malloc since
780 it may return the same address across multiple calls.
781 C++ operator new is not suitable because it is not required
782 to return a unique pointer; indeed, the standard placement new
783 just returns its argument. */
784 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl
))) == Pmode
785 && (! strcmp (tname
, "malloc")
786 || ! strcmp (tname
, "calloc")
787 || ! strcmp (tname
, "strdup")))
793 /* Return nonzero when tree represent call to longjmp. */
796 setjmp_call_p (fndecl
)
799 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
802 /* Detect flags (function attributes) from the function decl or type node. */
805 flags_from_decl_or_type (exp
)
810 /* ??? We can't set IS_MALLOC for function types? */
813 type
= TREE_TYPE (exp
);
815 /* The function exp may have the `malloc' attribute. */
816 if (DECL_P (exp
) && DECL_IS_MALLOC (exp
))
819 /* The function exp may have the `pure' attribute. */
820 if (DECL_P (exp
) && DECL_IS_PURE (exp
))
821 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
823 if (TREE_NOTHROW (exp
))
824 flags
|= ECF_NOTHROW
;
827 if (TREE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
828 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
830 if (TREE_THIS_VOLATILE (exp
))
831 flags
|= ECF_NORETURN
;
833 /* Mark if the function returns with the stack pointer depressed. We
834 cannot consider it pure or constant in that case. */
835 if (TREE_CODE (type
) == FUNCTION_TYPE
&& TYPE_RETURNS_STACK_DEPRESSED (type
))
837 flags
|= ECF_SP_DEPRESSED
;
838 flags
&= ~(ECF_PURE
| ECF_CONST
| ECF_LIBCALL_BLOCK
);
844 /* Precompute all register parameters as described by ARGS, storing values
845 into fields within the ARGS array.
847 NUM_ACTUALS indicates the total number elements in the ARGS array.
849 Set REG_PARM_SEEN if we encounter a register parameter. */
852 precompute_register_parameters (num_actuals
, args
, reg_parm_seen
)
854 struct arg_data
*args
;
861 for (i
= 0; i
< num_actuals
; i
++)
862 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
866 if (args
[i
].value
== 0)
869 args
[i
].value
= expand_expr (args
[i
].tree_value
, NULL_RTX
,
871 preserve_temp_slots (args
[i
].value
);
874 /* ANSI doesn't require a sequence point here,
875 but PCC has one, so this will avoid some problems. */
879 /* If the value is a non-legitimate constant, force it into a
880 pseudo now. TLS symbols sometimes need a call to resolve. */
881 if (CONSTANT_P (args
[i
].value
)
882 && !LEGITIMATE_CONSTANT_P (args
[i
].value
))
883 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
885 /* If we are to promote the function arg to a wider mode,
888 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
890 = convert_modes (args
[i
].mode
,
891 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
892 args
[i
].value
, args
[i
].unsignedp
);
894 /* If the value is expensive, and we are inside an appropriately
895 short loop, put the value into a pseudo and then put the pseudo
898 For small register classes, also do this if this call uses
899 register parameters. This is to avoid reload conflicts while
900 loading the parameters registers. */
902 if ((! (GET_CODE (args
[i
].value
) == REG
903 || (GET_CODE (args
[i
].value
) == SUBREG
904 && GET_CODE (SUBREG_REG (args
[i
].value
)) == REG
)))
905 && args
[i
].mode
!= BLKmode
906 && rtx_cost (args
[i
].value
, SET
) > COSTS_N_INSNS (1)
907 && ((SMALL_REGISTER_CLASSES
&& *reg_parm_seen
)
908 || preserve_subexpressions_p ()))
909 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
913 #ifdef REG_PARM_STACK_SPACE
915 /* The argument list is the property of the called routine and it
916 may clobber it. If the fixed area has been used for previous
917 parameters, we must save and restore it. */
920 save_fixed_argument_area (reg_parm_stack_space
, argblock
,
921 low_to_save
, high_to_save
)
922 int reg_parm_stack_space
;
928 rtx save_area
= NULL_RTX
;
930 /* Compute the boundary of the that needs to be saved, if any. */
931 #ifdef ARGS_GROW_DOWNWARD
932 for (i
= 0; i
< reg_parm_stack_space
+ 1; i
++)
934 for (i
= 0; i
< reg_parm_stack_space
; i
++)
937 if (i
>= highest_outgoing_arg_in_use
938 || stack_usage_map
[i
] == 0)
941 if (*low_to_save
== -1)
947 if (*low_to_save
>= 0)
949 int num_to_save
= *high_to_save
- *low_to_save
+ 1;
950 enum machine_mode save_mode
951 = mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
954 /* If we don't have the required alignment, must do this in BLKmode. */
955 if ((*low_to_save
& (MIN (GET_MODE_SIZE (save_mode
),
956 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
959 #ifdef ARGS_GROW_DOWNWARD
961 = gen_rtx_MEM (save_mode
,
962 memory_address (save_mode
,
963 plus_constant (argblock
,
966 stack_area
= gen_rtx_MEM (save_mode
,
967 memory_address (save_mode
,
968 plus_constant (argblock
,
972 set_mem_align (stack_area
, PARM_BOUNDARY
);
973 if (save_mode
== BLKmode
)
975 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
976 emit_block_move (validize_mem (save_area
), stack_area
,
977 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
981 save_area
= gen_reg_rtx (save_mode
);
982 emit_move_insn (save_area
, stack_area
);
990 restore_fixed_argument_area (save_area
, argblock
, high_to_save
, low_to_save
)
996 enum machine_mode save_mode
= GET_MODE (save_area
);
997 #ifdef ARGS_GROW_DOWNWARD
999 = gen_rtx_MEM (save_mode
,
1000 memory_address (save_mode
,
1001 plus_constant (argblock
,
1005 = gen_rtx_MEM (save_mode
,
1006 memory_address (save_mode
,
1007 plus_constant (argblock
,
1011 if (save_mode
!= BLKmode
)
1012 emit_move_insn (stack_area
, save_area
);
1014 emit_block_move (stack_area
, validize_mem (save_area
),
1015 GEN_INT (high_to_save
- low_to_save
+ 1),
1016 BLOCK_OP_CALL_PARM
);
1018 #endif /* REG_PARM_STACK_SPACE */
1020 /* If any elements in ARGS refer to parameters that are to be passed in
1021 registers, but not in memory, and whose alignment does not permit a
1022 direct copy into registers. Copy the values into a group of pseudos
1023 which we will later copy into the appropriate hard registers.
1025 Pseudos for each unaligned argument will be stored into the array
1026 args[argnum].aligned_regs. The caller is responsible for deallocating
1027 the aligned_regs array if it is nonzero. */
1030 store_unaligned_arguments_into_pseudos (args
, num_actuals
)
1031 struct arg_data
*args
;
1036 for (i
= 0; i
< num_actuals
; i
++)
1037 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
1038 && args
[i
].mode
== BLKmode
1039 && (TYPE_ALIGN (TREE_TYPE (args
[i
].tree_value
))
1040 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
1042 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1043 int big_endian_correction
= 0;
1045 args
[i
].n_aligned_regs
1046 = args
[i
].partial
? args
[i
].partial
1047 : (bytes
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1049 args
[i
].aligned_regs
= (rtx
*) xmalloc (sizeof (rtx
)
1050 * args
[i
].n_aligned_regs
);
1052 /* Structures smaller than a word are aligned to the least
1053 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1054 this means we must skip the empty high order bytes when
1055 calculating the bit offset. */
1056 if (BYTES_BIG_ENDIAN
1057 && !FUNCTION_ARG_REG_LITTLE_ENDIAN
1058 && bytes
< UNITS_PER_WORD
)
1059 big_endian_correction
= (BITS_PER_WORD
- (bytes
* BITS_PER_UNIT
));
1061 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1063 rtx reg
= gen_reg_rtx (word_mode
);
1064 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
1065 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
1067 args
[i
].aligned_regs
[j
] = reg
;
1069 /* There is no need to restrict this code to loading items
1070 in TYPE_ALIGN sized hunks. The bitfield instructions can
1071 load up entire word sized registers efficiently.
1073 ??? This may not be needed anymore.
1074 We use to emit a clobber here but that doesn't let later
1075 passes optimize the instructions we emit. By storing 0 into
1076 the register later passes know the first AND to zero out the
1077 bitfield being set in the register is unnecessary. The store
1078 of 0 will be deleted as will at least the first AND. */
1080 emit_move_insn (reg
, const0_rtx
);
1082 bytes
-= bitsize
/ BITS_PER_UNIT
;
1083 store_bit_field (reg
, bitsize
, big_endian_correction
, word_mode
,
1084 extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
1085 word_mode
, word_mode
,
1092 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1095 NUM_ACTUALS is the total number of parameters.
1097 N_NAMED_ARGS is the total number of named arguments.
1099 FNDECL is the tree code for the target of this call (if known)
1101 ARGS_SO_FAR holds state needed by the target to know where to place
1104 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1105 for arguments which are passed in registers.
1107 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1108 and may be modified by this routine.
1110 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1111 flags which may may be modified by this routine. */
1114 initialize_argument_information (num_actuals
, args
, args_size
, n_named_args
,
1115 actparms
, fndecl
, args_so_far
,
1116 reg_parm_stack_space
, old_stack_level
,
1117 old_pending_adj
, must_preallocate
,
1119 int num_actuals ATTRIBUTE_UNUSED
;
1120 struct arg_data
*args
;
1121 struct args_size
*args_size
;
1122 int n_named_args ATTRIBUTE_UNUSED
;
1125 CUMULATIVE_ARGS
*args_so_far
;
1126 int reg_parm_stack_space
;
1127 rtx
*old_stack_level
;
1128 int *old_pending_adj
;
1129 int *must_preallocate
;
1132 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1135 /* Count arg position in order args appear. */
1138 struct args_size alignment_pad
;
1142 args_size
->constant
= 0;
1145 /* In this loop, we consider args in the order they are written.
1146 We fill up ARGS from the front or from the back if necessary
1147 so that in any case the first arg to be pushed ends up at the front. */
1149 if (PUSH_ARGS_REVERSED
)
1151 i
= num_actuals
- 1, inc
= -1;
1152 /* In this case, must reverse order of args
1153 so that we compute and push the last arg first. */
1160 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1161 for (p
= actparms
, argpos
= 0; p
; p
= TREE_CHAIN (p
), i
+= inc
, argpos
++)
1163 tree type
= TREE_TYPE (TREE_VALUE (p
));
1165 enum machine_mode mode
;
1167 args
[i
].tree_value
= TREE_VALUE (p
);
1169 /* Replace erroneous argument with constant zero. */
1170 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1171 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1173 /* If TYPE is a transparent union, pass things the way we would
1174 pass the first field of the union. We have already verified that
1175 the modes are the same. */
1176 if (TREE_CODE (type
) == UNION_TYPE
&& TYPE_TRANSPARENT_UNION (type
))
1177 type
= TREE_TYPE (TYPE_FIELDS (type
));
1179 /* Decide where to pass this arg.
1181 args[i].reg is nonzero if all or part is passed in registers.
1183 args[i].partial is nonzero if part but not all is passed in registers,
1184 and the exact value says how many words are passed in registers.
1186 args[i].pass_on_stack is nonzero if the argument must at least be
1187 computed on the stack. It may then be loaded back into registers
1188 if args[i].reg is nonzero.
1190 These decisions are driven by the FUNCTION_... macros and must agree
1191 with those made by function.c. */
1193 /* See if this argument should be passed by invisible reference. */
1194 if ((TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1195 && contains_placeholder_p (TYPE_SIZE (type
)))
1196 || TREE_ADDRESSABLE (type
)
1197 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1198 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far
, TYPE_MODE (type
),
1199 type
, argpos
< n_named_args
)
1203 /* If we're compiling a thunk, pass through invisible
1204 references instead of making a copy. */
1205 if (current_function_is_thunk
1206 #ifdef FUNCTION_ARG_CALLEE_COPIES
1207 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far
, TYPE_MODE (type
),
1208 type
, argpos
< n_named_args
)
1209 /* If it's in a register, we must make a copy of it too. */
1210 /* ??? Is this a sufficient test? Is there a better one? */
1211 && !(TREE_CODE (args
[i
].tree_value
) == VAR_DECL
1212 && REG_P (DECL_RTL (args
[i
].tree_value
)))
1213 && ! TREE_ADDRESSABLE (type
))
1217 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1218 new object from the argument. If we are passing by
1219 invisible reference, the callee will do that for us, so we
1220 can strip off the TARGET_EXPR. This is not always safe,
1221 but it is safe in the only case where this is a useful
1222 optimization; namely, when the argument is a plain object.
1223 In that case, the frontend is just asking the backend to
1224 make a bitwise copy of the argument. */
1226 if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1227 && (DECL_P (TREE_OPERAND (args
[i
].tree_value
, 1)))
1228 && ! REG_P (DECL_RTL (TREE_OPERAND (args
[i
].tree_value
, 1))))
1229 args
[i
].tree_value
= TREE_OPERAND (args
[i
].tree_value
, 1);
1231 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1232 build_pointer_type (type
),
1233 args
[i
].tree_value
);
1234 type
= build_pointer_type (type
);
1236 else if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
)
1238 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1239 We implement this by passing the address of the temporary
1240 rather than expanding it into another allocated slot. */
1241 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1242 build_pointer_type (type
),
1243 args
[i
].tree_value
);
1244 type
= build_pointer_type (type
);
1248 /* We make a copy of the object and pass the address to the
1249 function being called. */
1252 if (!COMPLETE_TYPE_P (type
)
1253 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1254 || (flag_stack_check
&& ! STACK_CHECK_BUILTIN
1255 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type
),
1256 STACK_CHECK_MAX_VAR_SIZE
))))
1258 /* This is a variable-sized object. Make space on the stack
1260 rtx size_rtx
= expr_size (TREE_VALUE (p
));
1262 if (*old_stack_level
== 0)
1264 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1265 *old_pending_adj
= pending_stack_adjust
;
1266 pending_stack_adjust
= 0;
1269 copy
= gen_rtx_MEM (BLKmode
,
1270 allocate_dynamic_stack_space
1271 (size_rtx
, NULL_RTX
, TYPE_ALIGN (type
)));
1272 set_mem_attributes (copy
, type
, 1);
1275 copy
= assign_temp (type
, 0, 1, 0);
1277 store_expr (args
[i
].tree_value
, copy
, 0);
1278 *ecf_flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
1280 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1281 build_pointer_type (type
),
1282 make_tree (type
, copy
));
1283 type
= build_pointer_type (type
);
1287 mode
= TYPE_MODE (type
);
1288 unsignedp
= TREE_UNSIGNED (type
);
1290 #ifdef PROMOTE_FUNCTION_ARGS
1291 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
1294 args
[i
].unsignedp
= unsignedp
;
1295 args
[i
].mode
= mode
;
1297 args
[i
].reg
= FUNCTION_ARG (*args_so_far
, mode
, type
,
1298 argpos
< n_named_args
);
1299 #ifdef FUNCTION_INCOMING_ARG
1300 /* If this is a sibling call and the machine has register windows, the
1301 register window has to be unwinded before calling the routine, so
1302 arguments have to go into the incoming registers. */
1303 args
[i
].tail_call_reg
= FUNCTION_INCOMING_ARG (*args_so_far
, mode
, type
,
1304 argpos
< n_named_args
);
1306 args
[i
].tail_call_reg
= args
[i
].reg
;
1309 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1312 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far
, mode
, type
,
1313 argpos
< n_named_args
);
1316 args
[i
].pass_on_stack
= MUST_PASS_IN_STACK (mode
, type
);
1318 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1319 it means that we are to pass this arg in the register(s) designated
1320 by the PARALLEL, but also to pass it in the stack. */
1321 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1322 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1323 args
[i
].pass_on_stack
= 1;
1325 /* If this is an addressable type, we must preallocate the stack
1326 since we must evaluate the object into its final location.
1328 If this is to be passed in both registers and the stack, it is simpler
1330 if (TREE_ADDRESSABLE (type
)
1331 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1332 *must_preallocate
= 1;
1334 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1335 we cannot consider this function call constant. */
1336 if (TREE_ADDRESSABLE (type
))
1337 *ecf_flags
&= ~ECF_LIBCALL_BLOCK
;
1339 /* Compute the stack-size of this argument. */
1340 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1341 || reg_parm_stack_space
> 0
1342 || args
[i
].pass_on_stack
)
1343 locate_and_pad_parm (mode
, type
,
1344 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1349 fndecl
, args_size
, &args
[i
].offset
,
1350 &args
[i
].size
, &alignment_pad
);
1352 #ifndef ARGS_GROW_DOWNWARD
1353 args
[i
].slot_offset
= *args_size
;
1356 args
[i
].alignment_pad
= alignment_pad
;
1358 /* If a part of the arg was put into registers,
1359 don't include that part in the amount pushed. */
1360 if (reg_parm_stack_space
== 0 && ! args
[i
].pass_on_stack
)
1361 args
[i
].size
.constant
-= ((args
[i
].partial
* UNITS_PER_WORD
)
1362 / (PARM_BOUNDARY
/ BITS_PER_UNIT
)
1363 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
1365 /* Update ARGS_SIZE, the total stack space for args so far. */
1367 args_size
->constant
+= args
[i
].size
.constant
;
1368 if (args
[i
].size
.var
)
1370 ADD_PARM_SIZE (*args_size
, args
[i
].size
.var
);
1373 /* Since the slot offset points to the bottom of the slot,
1374 we must record it after incrementing if the args grow down. */
1375 #ifdef ARGS_GROW_DOWNWARD
1376 args
[i
].slot_offset
= *args_size
;
1378 args
[i
].slot_offset
.constant
= -args_size
->constant
;
1380 SUB_PARM_SIZE (args
[i
].slot_offset
, args_size
->var
);
1383 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1384 have been used, etc. */
1386 FUNCTION_ARG_ADVANCE (*args_so_far
, TYPE_MODE (type
), type
,
1387 argpos
< n_named_args
);
1391 /* Update ARGS_SIZE to contain the total size for the argument block.
1392 Return the original constant component of the argument block's size.
1394 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1395 for arguments passed in registers. */
1398 compute_argument_block_size (reg_parm_stack_space
, args_size
,
1399 preferred_stack_boundary
)
1400 int reg_parm_stack_space
;
1401 struct args_size
*args_size
;
1402 int preferred_stack_boundary ATTRIBUTE_UNUSED
;
1404 int unadjusted_args_size
= args_size
->constant
;
1406 /* For accumulate outgoing args mode we don't need to align, since the frame
1407 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1408 backends from generating misaligned frame sizes. */
1409 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1410 preferred_stack_boundary
= STACK_BOUNDARY
;
1412 /* Compute the actual size of the argument block required. The variable
1413 and constant sizes must be combined, the size may have to be rounded,
1414 and there may be a minimum required size. */
1418 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1419 args_size
->constant
= 0;
1421 preferred_stack_boundary
/= BITS_PER_UNIT
;
1422 if (preferred_stack_boundary
> 1)
1424 /* We don't handle this case yet. To handle it correctly we have
1425 to add the delta, round and subtract the delta.
1426 Currently no machine description requires this support. */
1427 if (stack_pointer_delta
& (preferred_stack_boundary
- 1))
1429 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1432 if (reg_parm_stack_space
> 0)
1435 = size_binop (MAX_EXPR
, args_size
->var
,
1436 ssize_int (reg_parm_stack_space
));
1438 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1439 /* The area corresponding to register parameters is not to count in
1440 the size of the block we need. So make the adjustment. */
1442 = size_binop (MINUS_EXPR
, args_size
->var
,
1443 ssize_int (reg_parm_stack_space
));
1449 preferred_stack_boundary
/= BITS_PER_UNIT
;
1450 if (preferred_stack_boundary
< 1)
1451 preferred_stack_boundary
= 1;
1452 args_size
->constant
= (((args_size
->constant
1453 + stack_pointer_delta
1454 + preferred_stack_boundary
- 1)
1455 / preferred_stack_boundary
1456 * preferred_stack_boundary
)
1457 - stack_pointer_delta
);
1459 args_size
->constant
= MAX (args_size
->constant
,
1460 reg_parm_stack_space
);
1462 #ifdef MAYBE_REG_PARM_STACK_SPACE
1463 if (reg_parm_stack_space
== 0)
1464 args_size
->constant
= 0;
1467 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1468 args_size
->constant
-= reg_parm_stack_space
;
1471 return unadjusted_args_size
;
1474 /* Precompute parameters as needed for a function call.
1476 FLAGS is mask of ECF_* constants.
1478 NUM_ACTUALS is the number of arguments.
1480 ARGS is an array containing information for each argument; this
1481 routine fills in the INITIAL_VALUE and VALUE fields for each
1482 precomputed argument. */
1485 precompute_arguments (flags
, num_actuals
, args
)
1488 struct arg_data
*args
;
1492 /* If this function call is cse'able, precompute all the parameters.
1493 Note that if the parameter is constructed into a temporary, this will
1494 cause an additional copy because the parameter will be constructed
1495 into a temporary location and then copied into the outgoing arguments.
1496 If a parameter contains a call to alloca and this function uses the
1497 stack, precompute the parameter. */
1499 /* If we preallocated the stack space, and some arguments must be passed
1500 on the stack, then we must precompute any parameter which contains a
1501 function call which will store arguments on the stack.
1502 Otherwise, evaluating the parameter may clobber previous parameters
1503 which have already been stored into the stack. (we have code to avoid
1504 such case by saving the outgoing stack arguments, but it results in
1507 for (i
= 0; i
< num_actuals
; i
++)
1508 if ((flags
& ECF_LIBCALL_BLOCK
)
1509 || calls_function (args
[i
].tree_value
, !ACCUMULATE_OUTGOING_ARGS
))
1511 enum machine_mode mode
;
1513 /* If this is an addressable type, we cannot pre-evaluate it. */
1514 if (TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
)))
1518 = expand_expr (args
[i
].tree_value
, NULL_RTX
, VOIDmode
, 0);
1520 /* ANSI doesn't require a sequence point here,
1521 but PCC has one, so this will avoid some problems. */
1524 args
[i
].initial_value
= args
[i
].value
1525 = protect_from_queue (args
[i
].value
, 0);
1527 mode
= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
));
1528 if (mode
!= args
[i
].mode
)
1531 = convert_modes (args
[i
].mode
, mode
,
1532 args
[i
].value
, args
[i
].unsignedp
);
1533 #ifdef PROMOTE_FOR_CALL_ONLY
1534 /* CSE will replace this only if it contains args[i].value
1535 pseudo, so convert it down to the declared mode using
1537 if (GET_CODE (args
[i
].value
) == REG
1538 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
)
1540 args
[i
].initial_value
1541 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1542 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1543 SUBREG_PROMOTED_UNSIGNED_SET (args
[i
].initial_value
,
1551 /* Given the current state of MUST_PREALLOCATE and information about
1552 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1553 compute and return the final value for MUST_PREALLOCATE. */
1556 finalize_must_preallocate (must_preallocate
, num_actuals
, args
, args_size
)
1557 int must_preallocate
;
1559 struct arg_data
*args
;
1560 struct args_size
*args_size
;
1562 /* See if we have or want to preallocate stack space.
1564 If we would have to push a partially-in-regs parm
1565 before other stack parms, preallocate stack space instead.
1567 If the size of some parm is not a multiple of the required stack
1568 alignment, we must preallocate.
1570 If the total size of arguments that would otherwise create a copy in
1571 a temporary (such as a CALL) is more than half the total argument list
1572 size, preallocation is faster.
1574 Another reason to preallocate is if we have a machine (like the m88k)
1575 where stack alignment is required to be maintained between every
1576 pair of insns, not just when the call is made. However, we assume here
1577 that such machines either do not have push insns (and hence preallocation
1578 would occur anyway) or the problem is taken care of with
1581 if (! must_preallocate
)
1583 int partial_seen
= 0;
1584 int copy_to_evaluate_size
= 0;
1587 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1589 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1591 else if (partial_seen
&& args
[i
].reg
== 0)
1592 must_preallocate
= 1;
1594 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1595 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1596 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1597 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1598 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1599 copy_to_evaluate_size
1600 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1603 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1604 && args_size
->constant
> 0)
1605 must_preallocate
= 1;
1607 return must_preallocate
;
1610 /* If we preallocated stack space, compute the address of each argument
1611 and store it into the ARGS array.
1613 We need not ensure it is a valid memory address here; it will be
1614 validized when it is used.
1616 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1619 compute_argument_addresses (args
, argblock
, num_actuals
)
1620 struct arg_data
*args
;
1626 rtx arg_reg
= argblock
;
1627 int i
, arg_offset
= 0;
1629 if (GET_CODE (argblock
) == PLUS
)
1630 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1632 for (i
= 0; i
< num_actuals
; i
++)
1634 rtx offset
= ARGS_SIZE_RTX (args
[i
].offset
);
1635 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].slot_offset
);
1638 /* Skip this parm if it will not be passed on the stack. */
1639 if (! args
[i
].pass_on_stack
&& args
[i
].reg
!= 0)
1642 if (GET_CODE (offset
) == CONST_INT
)
1643 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1645 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1647 addr
= plus_constant (addr
, arg_offset
);
1648 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1649 set_mem_attributes (args
[i
].stack
,
1650 TREE_TYPE (args
[i
].tree_value
), 1);
1652 if (GET_CODE (slot_offset
) == CONST_INT
)
1653 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1655 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1657 addr
= plus_constant (addr
, arg_offset
);
1658 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1659 set_mem_attributes (args
[i
].stack_slot
,
1660 TREE_TYPE (args
[i
].tree_value
), 1);
1662 /* Function incoming arguments may overlap with sibling call
1663 outgoing arguments and we cannot allow reordering of reads
1664 from function arguments with stores to outgoing arguments
1665 of sibling calls. */
1666 set_mem_alias_set (args
[i
].stack
, 0);
1667 set_mem_alias_set (args
[i
].stack_slot
, 0);
1672 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1673 in a call instruction.
1675 FNDECL is the tree node for the target function. For an indirect call
1676 FNDECL will be NULL_TREE.
1678 EXP is the CALL_EXPR for this call. */
1681 rtx_for_function_call (fndecl
, exp
)
1687 /* Get the function to call, in the form of RTL. */
1690 /* If this is the first use of the function, see if we need to
1691 make an external definition for it. */
1692 if (! TREE_USED (fndecl
))
1694 assemble_external (fndecl
);
1695 TREE_USED (fndecl
) = 1;
1698 /* Get a SYMBOL_REF rtx for the function address. */
1699 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1702 /* Generate an rtx (probably a pseudo-register) for the address. */
1707 = expand_expr (TREE_OPERAND (exp
, 0), NULL_RTX
, VOIDmode
, 0);
1708 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1714 /* Do the register loads required for any wholly-register parms or any
1715 parms which are passed both on the stack and in a register. Their
1716 expressions were already evaluated.
1718 Mark all register-parms as living through the call, putting these USE
1719 insns in the CALL_INSN_FUNCTION_USAGE field. */
1722 load_register_parameters (args
, num_actuals
, call_fusage
, flags
)
1723 struct arg_data
*args
;
1730 #ifdef LOAD_ARGS_REVERSED
1731 for (i
= num_actuals
- 1; i
>= 0; i
--)
1733 for (i
= 0; i
< num_actuals
; i
++)
1736 rtx reg
= ((flags
& ECF_SIBCALL
)
1737 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1738 int partial
= args
[i
].partial
;
1743 /* Set to non-negative if must move a word at a time, even if just
1744 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1745 we just use a normal move insn. This value can be zero if the
1746 argument is a zero size structure with no fields. */
1747 nregs
= (partial
? partial
1748 : (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1749 ? ((int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
))
1750 + (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
)
1753 /* Handle calls that pass values in multiple non-contiguous
1754 locations. The Irix 6 ABI has examples of this. */
1756 if (GET_CODE (reg
) == PARALLEL
)
1757 emit_group_load (reg
, args
[i
].value
,
1758 int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
)));
1760 /* If simple case, just do move. If normal partial, store_one_arg
1761 has already loaded the register for us. In all other cases,
1762 load the register(s) from memory. */
1764 else if (nregs
== -1)
1765 emit_move_insn (reg
, args
[i
].value
);
1767 /* If we have pre-computed the values to put in the registers in
1768 the case of non-aligned structures, copy them in now. */
1770 else if (args
[i
].n_aligned_regs
!= 0)
1771 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1772 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1773 args
[i
].aligned_regs
[j
]);
1775 else if (partial
== 0 || args
[i
].pass_on_stack
)
1776 move_block_to_reg (REGNO (reg
),
1777 validize_mem (args
[i
].value
), nregs
,
1780 /* Handle calls that pass values in multiple non-contiguous
1781 locations. The Irix 6 ABI has examples of this. */
1782 if (GET_CODE (reg
) == PARALLEL
)
1783 use_group_regs (call_fusage
, reg
);
1784 else if (nregs
== -1)
1785 use_reg (call_fusage
, reg
);
1787 use_regs (call_fusage
, REGNO (reg
), nregs
== 0 ? 1 : nregs
);
1792 /* Try to integrate function. See expand_inline_function for documentation
1793 about the parameters. */
1796 try_to_integrate (fndecl
, actparms
, target
, ignore
, type
, structure_value_addr
)
1802 rtx structure_value_addr
;
1807 rtx old_stack_level
= 0;
1808 int reg_parm_stack_space
= 0;
1810 #ifdef REG_PARM_STACK_SPACE
1811 #ifdef MAYBE_REG_PARM_STACK_SPACE
1812 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
1814 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
1818 before_call
= get_last_insn ();
1820 timevar_push (TV_INTEGRATION
);
1822 temp
= expand_inline_function (fndecl
, actparms
, target
,
1824 structure_value_addr
);
1826 timevar_pop (TV_INTEGRATION
);
1828 /* If inlining succeeded, return. */
1829 if (temp
!= (rtx
) (size_t) - 1)
1831 if (ACCUMULATE_OUTGOING_ARGS
)
1833 /* If the outgoing argument list must be preserved, push
1834 the stack before executing the inlined function if it
1837 for (i
= reg_parm_stack_space
- 1; i
>= 0; i
--)
1838 if (i
< highest_outgoing_arg_in_use
&& stack_usage_map
[i
] != 0)
1841 if (stack_arg_under_construction
|| i
>= 0)
1844 = before_call
? NEXT_INSN (before_call
) : get_insns ();
1845 rtx insn
= NULL_RTX
, seq
;
1847 /* Look for a call in the inline function code.
1848 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1849 nonzero then there is a call and it is not necessary
1850 to scan the insns. */
1852 if (DECL_SAVED_INSNS (fndecl
)->outgoing_args_size
== 0)
1853 for (insn
= first_insn
; insn
; insn
= NEXT_INSN (insn
))
1854 if (GET_CODE (insn
) == CALL_INSN
)
1859 /* Reserve enough stack space so that the largest
1860 argument list of any function call in the inline
1861 function does not overlap the argument list being
1862 evaluated. This is usually an overestimate because
1863 allocate_dynamic_stack_space reserves space for an
1864 outgoing argument list in addition to the requested
1865 space, but there is no way to ask for stack space such
1866 that an argument list of a certain length can be
1869 Add the stack space reserved for register arguments, if
1870 any, in the inline function. What is really needed is the
1871 largest value of reg_parm_stack_space in the inline
1872 function, but that is not available. Using the current
1873 value of reg_parm_stack_space is wrong, but gives
1874 correct results on all supported machines. */
1876 int adjust
= (DECL_SAVED_INSNS (fndecl
)->outgoing_args_size
1877 + reg_parm_stack_space
);
1880 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
1881 allocate_dynamic_stack_space (GEN_INT (adjust
),
1882 NULL_RTX
, BITS_PER_UNIT
);
1885 emit_insn_before (seq
, first_insn
);
1886 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1891 /* If the result is equivalent to TARGET, return TARGET to simplify
1892 checks in store_expr. They can be equivalent but not equal in the
1893 case of a function that returns BLKmode. */
1894 if (temp
!= target
&& rtx_equal_p (temp
, target
))
1899 /* If inlining failed, mark FNDECL as needing to be compiled
1900 separately after all. If function was declared inline,
1902 if (DECL_INLINE (fndecl
) && warn_inline
&& !flag_no_inline
1903 && optimize
> 0 && !TREE_ADDRESSABLE (fndecl
))
1905 warning_with_decl (fndecl
, "inlining failed in call to `%s'");
1906 warning ("called from here");
1908 (*lang_hooks
.mark_addressable
) (fndecl
);
1909 return (rtx
) (size_t) - 1;
1912 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1913 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1914 bytes, then we would need to push some additional bytes to pad the
1915 arguments. So, we compute an adjust to the stack pointer for an
1916 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1917 bytes. Then, when the arguments are pushed the stack will be perfectly
1918 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1919 be popped after the call. Returns the adjustment. */
1922 combine_pending_stack_adjustment_and_call (unadjusted_args_size
,
1924 preferred_unit_stack_boundary
)
1925 int unadjusted_args_size
;
1926 struct args_size
*args_size
;
1927 int preferred_unit_stack_boundary
;
1929 /* The number of bytes to pop so that the stack will be
1930 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1931 HOST_WIDE_INT adjustment
;
1932 /* The alignment of the stack after the arguments are pushed, if we
1933 just pushed the arguments without adjust the stack here. */
1934 HOST_WIDE_INT unadjusted_alignment
;
1936 unadjusted_alignment
1937 = ((stack_pointer_delta
+ unadjusted_args_size
)
1938 % preferred_unit_stack_boundary
);
1940 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1941 as possible -- leaving just enough left to cancel out the
1942 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1943 PENDING_STACK_ADJUST is non-negative, and congruent to
1944 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1946 /* Begin by trying to pop all the bytes. */
1947 unadjusted_alignment
1948 = (unadjusted_alignment
1949 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1950 adjustment
= pending_stack_adjust
;
1951 /* Push enough additional bytes that the stack will be aligned
1952 after the arguments are pushed. */
1953 if (preferred_unit_stack_boundary
> 1)
1955 if (unadjusted_alignment
> 0)
1956 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1958 adjustment
+= unadjusted_alignment
;
1961 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1962 bytes after the call. The right number is the entire
1963 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1964 by the arguments in the first place. */
1966 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1971 /* Scan X expression if it does not dereference any argument slots
1972 we already clobbered by tail call arguments (as noted in stored_args_map
1974 Return nonzero if X expression dereferences such argument slots,
1978 check_sibcall_argument_overlap_1 (x
)
1989 code
= GET_CODE (x
);
1993 if (XEXP (x
, 0) == current_function_internal_arg_pointer
)
1995 else if (GET_CODE (XEXP (x
, 0)) == PLUS
1996 && XEXP (XEXP (x
, 0), 0) ==
1997 current_function_internal_arg_pointer
1998 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
)
1999 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
2003 #ifdef ARGS_GROW_DOWNWARD
2004 i
= -i
- GET_MODE_SIZE (GET_MODE (x
));
2007 for (k
= 0; k
< GET_MODE_SIZE (GET_MODE (x
)); k
++)
2008 if (i
+ k
< stored_args_map
->n_bits
2009 && TEST_BIT (stored_args_map
, i
+ k
))
2015 /* Scan all subexpressions. */
2016 fmt
= GET_RTX_FORMAT (code
);
2017 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
2021 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
2024 else if (*fmt
== 'E')
2026 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2027 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
2034 /* Scan sequence after INSN if it does not dereference any argument slots
2035 we already clobbered by tail call arguments (as noted in stored_args_map
2036 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2037 Return nonzero if sequence after INSN dereferences such argument slots,
2041 check_sibcall_argument_overlap (insn
, arg
)
2043 struct arg_data
*arg
;
2047 if (insn
== NULL_RTX
)
2048 insn
= get_insns ();
2050 insn
= NEXT_INSN (insn
);
2052 for (; insn
; insn
= NEXT_INSN (insn
))
2054 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
2057 #ifdef ARGS_GROW_DOWNWARD
2058 low
= -arg
->slot_offset
.constant
- arg
->size
.constant
;
2060 low
= arg
->slot_offset
.constant
;
2063 for (high
= low
+ arg
->size
.constant
; low
< high
; low
++)
2064 SET_BIT (stored_args_map
, low
);
2065 return insn
!= NULL_RTX
;
2068 /* Generate all the code for a function call
2069 and return an rtx for its value.
2070 Store the value in TARGET (specified as an rtx) if convenient.
2071 If the value is stored in TARGET then TARGET is returned.
2072 If IGNORE is nonzero, then we ignore the value of the function call. */
2075 expand_call (exp
, target
, ignore
)
2080 /* Nonzero if we are currently expanding a call. */
2081 static int currently_expanding_call
= 0;
2083 /* List of actual parameters. */
2084 tree actparms
= TREE_OPERAND (exp
, 1);
2085 /* RTX for the function to be called. */
2087 /* Sequence of insns to perform a tail recursive "call". */
2088 rtx tail_recursion_insns
= NULL_RTX
;
2089 /* Sequence of insns to perform a normal "call". */
2090 rtx normal_call_insns
= NULL_RTX
;
2091 /* Sequence of insns to perform a tail recursive "call". */
2092 rtx tail_call_insns
= NULL_RTX
;
2093 /* Data type of the function. */
2095 /* Declaration of the function being called,
2096 or 0 if the function is computed (not known by name). */
2099 int try_tail_call
= 1;
2100 int try_tail_recursion
= 1;
2103 /* Register in which non-BLKmode value will be returned,
2104 or 0 if no value or if value is BLKmode. */
2106 /* Address where we should return a BLKmode value;
2107 0 if value not BLKmode. */
2108 rtx structure_value_addr
= 0;
2109 /* Nonzero if that address is being passed by treating it as
2110 an extra, implicit first parameter. Otherwise,
2111 it is passed by being copied directly into struct_value_rtx. */
2112 int structure_value_addr_parm
= 0;
2113 /* Size of aggregate value wanted, or zero if none wanted
2114 or if we are using the non-reentrant PCC calling convention
2115 or expecting the value in registers. */
2116 HOST_WIDE_INT struct_value_size
= 0;
2117 /* Nonzero if called function returns an aggregate in memory PCC style,
2118 by returning the address of where to find it. */
2119 int pcc_struct_value
= 0;
2121 /* Number of actual parameters in this call, including struct value addr. */
2123 /* Number of named args. Args after this are anonymous ones
2124 and they must all go on the stack. */
2127 /* Vector of information about each argument.
2128 Arguments are numbered in the order they will be pushed,
2129 not the order they are written. */
2130 struct arg_data
*args
;
2132 /* Total size in bytes of all the stack-parms scanned so far. */
2133 struct args_size args_size
;
2134 struct args_size adjusted_args_size
;
2135 /* Size of arguments before any adjustments (such as rounding). */
2136 int unadjusted_args_size
;
2137 /* Data on reg parms scanned so far. */
2138 CUMULATIVE_ARGS args_so_far
;
2139 /* Nonzero if a reg parm has been scanned. */
2141 /* Nonzero if this is an indirect function call. */
2143 /* Nonzero if we must avoid push-insns in the args for this call.
2144 If stack space is allocated for register parameters, but not by the
2145 caller, then it is preallocated in the fixed part of the stack frame.
2146 So the entire argument block must then be preallocated (i.e., we
2147 ignore PUSH_ROUNDING in that case). */
2149 int must_preallocate
= !PUSH_ARGS
;
2151 /* Size of the stack reserved for parameter registers. */
2152 int reg_parm_stack_space
= 0;
2154 /* Address of space preallocated for stack parms
2155 (on machines that lack push insns), or 0 if space not preallocated. */
2158 /* Mask of ECF_ flags. */
2160 /* Nonzero if this is a call to an inline function. */
2161 int is_integrable
= 0;
2162 #ifdef REG_PARM_STACK_SPACE
2163 /* Define the boundary of the register parm stack space that needs to be
2165 int low_to_save
= -1, high_to_save
;
2166 rtx save_area
= 0; /* Place that it is saved */
2169 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
2170 char *initial_stack_usage_map
= stack_usage_map
;
2171 int old_stack_arg_under_construction
= 0;
2173 rtx old_stack_level
= 0;
2174 int old_pending_adj
= 0;
2175 int old_inhibit_defer_pop
= inhibit_defer_pop
;
2176 int old_stack_allocated
;
2178 tree p
= TREE_OPERAND (exp
, 0);
2180 /* The alignment of the stack, in bits. */
2181 HOST_WIDE_INT preferred_stack_boundary
;
2182 /* The alignment of the stack, in bytes. */
2183 HOST_WIDE_INT preferred_unit_stack_boundary
;
2185 /* See if this is "nothrow" function call. */
2186 if (TREE_NOTHROW (exp
))
2187 flags
|= ECF_NOTHROW
;
2189 /* See if we can find a DECL-node for the actual function.
2190 As a result, decide whether this is a call to an integrable function. */
2192 fndecl
= get_callee_fndecl (exp
);
2196 && fndecl
!= current_function_decl
2197 && DECL_INLINE (fndecl
)
2198 && DECL_SAVED_INSNS (fndecl
)
2199 && DECL_SAVED_INSNS (fndecl
)->inlinable
)
2201 else if (! TREE_ADDRESSABLE (fndecl
))
2203 /* In case this function later becomes inlinable,
2204 record that there was already a non-inline call to it.
2206 Use abstraction instead of setting TREE_ADDRESSABLE
2208 if (DECL_INLINE (fndecl
) && warn_inline
&& !flag_no_inline
2211 warning_with_decl (fndecl
, "can't inline call to `%s'");
2212 warning ("called from here");
2214 (*lang_hooks
.mark_addressable
) (fndecl
);
2217 flags
|= flags_from_decl_or_type (fndecl
);
2220 /* If we don't have specific function to call, see if we have a
2221 attributes set in the type. */
2223 flags
|= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p
)));
2225 #ifdef REG_PARM_STACK_SPACE
2226 #ifdef MAYBE_REG_PARM_STACK_SPACE
2227 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
2229 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
2233 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2234 if (reg_parm_stack_space
> 0 && PUSH_ARGS
)
2235 must_preallocate
= 1;
2238 /* Warn if this value is an aggregate type,
2239 regardless of which calling convention we are using for it. */
2240 if (warn_aggregate_return
&& AGGREGATE_TYPE_P (TREE_TYPE (exp
)))
2241 warning ("function call has aggregate value");
2243 /* Set up a place to return a structure. */
2245 /* Cater to broken compilers. */
2246 if (aggregate_value_p (exp
))
2248 /* This call returns a big structure. */
2249 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
2251 #ifdef PCC_STATIC_STRUCT_RETURN
2253 pcc_struct_value
= 1;
2254 /* Easier than making that case work right. */
2257 /* In case this is a static function, note that it has been
2259 if (! TREE_ADDRESSABLE (fndecl
))
2260 (*lang_hooks
.mark_addressable
) (fndecl
);
2264 #else /* not PCC_STATIC_STRUCT_RETURN */
2266 struct_value_size
= int_size_in_bytes (TREE_TYPE (exp
));
2268 if (target
&& GET_CODE (target
) == MEM
)
2269 structure_value_addr
= XEXP (target
, 0);
2272 /* For variable-sized objects, we must be called with a target
2273 specified. If we were to allocate space on the stack here,
2274 we would have no way of knowing when to free it. */
2275 rtx d
= assign_temp (TREE_TYPE (exp
), 1, 1, 1);
2277 mark_temp_addr_taken (d
);
2278 structure_value_addr
= XEXP (d
, 0);
2282 #endif /* not PCC_STATIC_STRUCT_RETURN */
2285 /* If called function is inline, try to integrate it. */
2289 rtx temp
= try_to_integrate (fndecl
, actparms
, target
,
2290 ignore
, TREE_TYPE (exp
),
2291 structure_value_addr
);
2292 if (temp
!= (rtx
) (size_t) - 1)
2296 /* Figure out the amount to which the stack should be aligned. */
2297 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2299 /* Operand 0 is a pointer-to-function; get the type of the function. */
2300 funtype
= TREE_TYPE (TREE_OPERAND (exp
, 0));
2301 if (! POINTER_TYPE_P (funtype
))
2303 funtype
= TREE_TYPE (funtype
);
2305 /* See if this is a call to a function that can return more than once
2306 or a call to longjmp or malloc. */
2307 flags
|= special_function_p (fndecl
, flags
);
2309 if (flags
& ECF_MAY_BE_ALLOCA
)
2310 current_function_calls_alloca
= 1;
2312 /* If struct_value_rtx is 0, it means pass the address
2313 as if it were an extra parameter. */
2314 if (structure_value_addr
&& struct_value_rtx
== 0)
2316 /* If structure_value_addr is a REG other than
2317 virtual_outgoing_args_rtx, we can use always use it. If it
2318 is not a REG, we must always copy it into a register.
2319 If it is virtual_outgoing_args_rtx, we must copy it to another
2320 register in some cases. */
2321 rtx temp
= (GET_CODE (structure_value_addr
) != REG
2322 || (ACCUMULATE_OUTGOING_ARGS
2323 && stack_arg_under_construction
2324 && structure_value_addr
== virtual_outgoing_args_rtx
)
2325 ? copy_addr_to_reg (structure_value_addr
)
2326 : structure_value_addr
);
2329 = tree_cons (error_mark_node
,
2330 make_tree (build_pointer_type (TREE_TYPE (funtype
)),
2333 structure_value_addr_parm
= 1;
2336 /* Count the arguments and set NUM_ACTUALS. */
2337 for (p
= actparms
, num_actuals
= 0; p
; p
= TREE_CHAIN (p
))
2340 /* Compute number of named args.
2341 Normally, don't include the last named arg if anonymous args follow.
2342 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2343 (If no anonymous args follow, the result of list_length is actually
2344 one too large. This is harmless.)
2346 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2347 zero, this machine will be able to place unnamed args that were
2348 passed in registers into the stack. So treat all args as named.
2349 This allows the insns emitting for a specific argument list to be
2350 independent of the function declaration.
2352 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2353 reliable way to pass unnamed args in registers, so we must force
2354 them into memory. */
2356 if ((STRICT_ARGUMENT_NAMING
2357 || ! PRETEND_OUTGOING_VARARGS_NAMED
)
2358 && TYPE_ARG_TYPES (funtype
) != 0)
2360 = (list_length (TYPE_ARG_TYPES (funtype
))
2361 /* Don't include the last named arg. */
2362 - (STRICT_ARGUMENT_NAMING
? 0 : 1)
2363 /* Count the struct value address, if it is passed as a parm. */
2364 + structure_value_addr_parm
);
2366 /* If we know nothing, treat all args as named. */
2367 n_named_args
= num_actuals
;
2369 /* Start updating where the next arg would go.
2371 On some machines (such as the PA) indirect calls have a different
2372 calling convention than normal calls. The last argument in
2373 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2375 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, (fndecl
== 0));
2377 /* Make a vector to hold all the information about each arg. */
2378 args
= (struct arg_data
*) alloca (num_actuals
* sizeof (struct arg_data
));
2379 memset ((char *) args
, 0, num_actuals
* sizeof (struct arg_data
));
2381 /* Build up entries in the ARGS array, compute the size of the
2382 arguments into ARGS_SIZE, etc. */
2383 initialize_argument_information (num_actuals
, args
, &args_size
,
2384 n_named_args
, actparms
, fndecl
,
2385 &args_so_far
, reg_parm_stack_space
,
2386 &old_stack_level
, &old_pending_adj
,
2387 &must_preallocate
, &flags
);
2391 /* If this function requires a variable-sized argument list, don't
2392 try to make a cse'able block for this call. We may be able to
2393 do this eventually, but it is too complicated to keep track of
2394 what insns go in the cse'able block and which don't. */
2396 flags
&= ~ECF_LIBCALL_BLOCK
;
2397 must_preallocate
= 1;
2400 /* Now make final decision about preallocating stack space. */
2401 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2405 /* If the structure value address will reference the stack pointer, we
2406 must stabilize it. We don't need to do this if we know that we are
2407 not going to adjust the stack pointer in processing this call. */
2409 if (structure_value_addr
2410 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2411 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2412 structure_value_addr
))
2414 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2415 structure_value_addr
= copy_to_reg (structure_value_addr
);
2417 /* Tail calls can make things harder to debug, and we're traditionally
2418 pushed these optimizations into -O2. Don't try if we're already
2419 expanding a call, as that means we're an argument. Don't try if
2420 there's cleanups, as we know there's code to follow the call.
2422 If rtx_equal_function_value_matters is false, that means we've
2423 finished with regular parsing. Which means that some of the
2424 machinery we use to generate tail-calls is no longer in place.
2425 This is most often true of sjlj-exceptions, which we couldn't
2426 tail-call to anyway. */
2428 if (currently_expanding_call
++ != 0
2429 || !flag_optimize_sibling_calls
2430 || !rtx_equal_function_value_matters
2431 || any_pending_cleanups (1)
2433 try_tail_call
= try_tail_recursion
= 0;
2435 /* Tail recursion fails, when we are not dealing with recursive calls. */
2436 if (!try_tail_recursion
2437 || TREE_CODE (TREE_OPERAND (exp
, 0)) != ADDR_EXPR
2438 || TREE_OPERAND (TREE_OPERAND (exp
, 0), 0) != current_function_decl
)
2439 try_tail_recursion
= 0;
2441 /* Rest of purposes for tail call optimizations to fail. */
2443 #ifdef HAVE_sibcall_epilogue
2444 !HAVE_sibcall_epilogue
2449 /* Doing sibling call optimization needs some work, since
2450 structure_value_addr can be allocated on the stack.
2451 It does not seem worth the effort since few optimizable
2452 sibling calls will return a structure. */
2453 || structure_value_addr
!= NULL_RTX
2454 /* If the register holding the address is a callee saved
2455 register, then we lose. We have no way to prevent that,
2456 so we only allow calls to named functions. */
2457 /* ??? This could be done by having the insn constraints
2458 use a register class that is all call-clobbered. Any
2459 reload insns generated to fix things up would appear
2460 before the sibcall_epilogue. */
2461 || fndecl
== NULL_TREE
2462 || (flags
& (ECF_RETURNS_TWICE
| ECF_LONGJMP
))
2463 || TREE_THIS_VOLATILE (fndecl
)
2464 || !FUNCTION_OK_FOR_SIBCALL (fndecl
)
2465 /* If this function requires more stack slots than the current
2466 function, we cannot change it into a sibling call. */
2467 || args_size
.constant
> current_function_args_size
2468 /* If the callee pops its own arguments, then it must pop exactly
2469 the same number of arguments as the current function. */
2470 || RETURN_POPS_ARGS (fndecl
, funtype
, args_size
.constant
)
2471 != RETURN_POPS_ARGS (current_function_decl
,
2472 TREE_TYPE (current_function_decl
),
2473 current_function_args_size
))
2476 if (try_tail_call
|| try_tail_recursion
)
2479 actparms
= NULL_TREE
;
2480 /* Ok, we're going to give the tail call the old college try.
2481 This means we're going to evaluate the function arguments
2482 up to three times. There are two degrees of badness we can
2483 encounter, those that can be unsaved and those that can't.
2484 (See unsafe_for_reeval commentary for details.)
2486 Generate a new argument list. Pass safe arguments through
2487 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2488 For hard badness, evaluate them now and put their resulting
2489 rtx in a temporary VAR_DECL.
2491 initialize_argument_information has ordered the array for the
2492 order to be pushed, and we must remember this when reconstructing
2493 the original argument order. */
2495 if (PUSH_ARGS_REVERSED
)
2504 i
= num_actuals
- 1;
2508 for (; i
!= end
; i
+= inc
)
2510 switch (unsafe_for_reeval (args
[i
].tree_value
))
2515 case 1: /* Mildly unsafe. */
2516 args
[i
].tree_value
= unsave_expr (args
[i
].tree_value
);
2519 case 2: /* Wildly unsafe. */
2521 tree var
= build_decl (VAR_DECL
, NULL_TREE
,
2522 TREE_TYPE (args
[i
].tree_value
));
2524 expand_expr (args
[i
].tree_value
, NULL_RTX
,
2525 VOIDmode
, EXPAND_NORMAL
));
2526 args
[i
].tree_value
= var
;
2533 /* We need to build actparms for optimize_tail_recursion. We can
2534 safely trash away TREE_PURPOSE, since it is unused by this
2536 if (try_tail_recursion
)
2537 actparms
= tree_cons (NULL_TREE
, args
[i
].tree_value
, actparms
);
2539 /* Expanding one of those dangerous arguments could have added
2540 cleanups, but otherwise give it a whirl. */
2541 if (any_pending_cleanups (1))
2542 try_tail_call
= try_tail_recursion
= 0;
2545 /* Generate a tail recursion sequence when calling ourselves. */
2547 if (try_tail_recursion
)
2549 /* We want to emit any pending stack adjustments before the tail
2550 recursion "call". That way we know any adjustment after the tail
2551 recursion call can be ignored if we indeed use the tail recursion
2553 int save_pending_stack_adjust
= pending_stack_adjust
;
2554 int save_stack_pointer_delta
= stack_pointer_delta
;
2556 /* Emit any queued insns now; otherwise they would end up in
2557 only one of the alternates. */
2560 /* Use a new sequence to hold any RTL we generate. We do not even
2561 know if we will use this RTL yet. The final decision can not be
2562 made until after RTL generation for the entire function is
2565 /* If expanding any of the arguments creates cleanups, we can't
2566 do a tailcall. So, we'll need to pop the pending cleanups
2567 list. If, however, all goes well, and there are no cleanups
2568 then the call to expand_start_target_temps will have no
2570 expand_start_target_temps ();
2571 if (optimize_tail_recursion (actparms
, get_last_insn ()))
2573 if (any_pending_cleanups (1))
2574 try_tail_call
= try_tail_recursion
= 0;
2576 tail_recursion_insns
= get_insns ();
2578 expand_end_target_temps ();
2581 /* Restore the original pending stack adjustment for the sibling and
2582 normal call cases below. */
2583 pending_stack_adjust
= save_pending_stack_adjust
;
2584 stack_pointer_delta
= save_stack_pointer_delta
;
2587 if (profile_arc_flag
&& (flags
& ECF_FORK_OR_EXEC
))
2589 /* A fork duplicates the profile information, and an exec discards
2590 it. We can't rely on fork/exec to be paired. So write out the
2591 profile information we have gathered so far, and clear it. */
2592 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2593 is subject to race conditions, just as with multithreaded
2596 emit_library_call (gen_rtx_SYMBOL_REF (Pmode
, "__bb_fork_func"),
2601 /* Ensure current function's preferred stack boundary is at least
2602 what we need. We don't have to increase alignment for recursive
2604 if (cfun
->preferred_stack_boundary
< preferred_stack_boundary
2605 && fndecl
!= current_function_decl
)
2606 cfun
->preferred_stack_boundary
= preferred_stack_boundary
;
2608 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2610 function_call_count
++;
2612 /* We want to make two insn chains; one for a sibling call, the other
2613 for a normal call. We will select one of the two chains after
2614 initial RTL generation is complete. */
2615 for (pass
= 0; pass
< 2; pass
++)
2617 int sibcall_failure
= 0;
2618 /* We want to emit any pending stack adjustments before the tail
2619 recursion "call". That way we know any adjustment after the tail
2620 recursion call can be ignored if we indeed use the tail recursion
2622 int save_pending_stack_adjust
= 0;
2623 int save_stack_pointer_delta
= 0;
2625 rtx before_call
, next_arg_reg
;
2629 if (! try_tail_call
)
2632 /* Emit any queued insns now; otherwise they would end up in
2633 only one of the alternates. */
2636 /* State variables we need to save and restore between
2638 save_pending_stack_adjust
= pending_stack_adjust
;
2639 save_stack_pointer_delta
= stack_pointer_delta
;
2642 flags
&= ~ECF_SIBCALL
;
2644 flags
|= ECF_SIBCALL
;
2646 /* Other state variables that we must reinitialize each time
2647 through the loop (that are not initialized by the loop itself). */
2651 /* Start a new sequence for the normal call case.
2653 From this point on, if the sibling call fails, we want to set
2654 sibcall_failure instead of continuing the loop. */
2659 /* We know at this point that there are not currently any
2660 pending cleanups. If, however, in the process of evaluating
2661 the arguments we were to create some, we'll need to be
2662 able to get rid of them. */
2663 expand_start_target_temps ();
2666 /* Don't let pending stack adjusts add up to too much.
2667 Also, do all pending adjustments now if there is any chance
2668 this might be a call to alloca or if we are expanding a sibling
2669 call sequence or if we are calling a function that is to return
2670 with stack pointer depressed. */
2671 if (pending_stack_adjust
>= 32
2672 || (pending_stack_adjust
> 0
2673 && (flags
& (ECF_MAY_BE_ALLOCA
| ECF_SP_DEPRESSED
)))
2675 do_pending_stack_adjust ();
2677 /* When calling a const function, we must pop the stack args right away,
2678 so that the pop is deleted or moved with the call. */
2679 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
2682 #ifdef FINAL_REG_PARM_STACK_SPACE
2683 reg_parm_stack_space
= FINAL_REG_PARM_STACK_SPACE (args_size
.constant
,
2686 /* Precompute any arguments as needed. */
2688 precompute_arguments (flags
, num_actuals
, args
);
2690 /* Now we are about to start emitting insns that can be deleted
2691 if a libcall is deleted. */
2692 if (pass
&& (flags
& (ECF_LIBCALL_BLOCK
| ECF_MALLOC
)))
2695 adjusted_args_size
= args_size
;
2696 /* Compute the actual size of the argument block required. The variable
2697 and constant sizes must be combined, the size may have to be rounded,
2698 and there may be a minimum required size. When generating a sibcall
2699 pattern, do not round up, since we'll be re-using whatever space our
2701 unadjusted_args_size
2702 = compute_argument_block_size (reg_parm_stack_space
,
2703 &adjusted_args_size
,
2705 : preferred_stack_boundary
));
2707 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2709 /* The argument block when performing a sibling call is the
2710 incoming argument block. */
2713 argblock
= virtual_incoming_args_rtx
;
2715 #ifdef STACK_GROWS_DOWNWARD
2716 = plus_constant (argblock
, current_function_pretend_args_size
);
2718 = plus_constant (argblock
, -current_function_pretend_args_size
);
2720 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2721 sbitmap_zero (stored_args_map
);
2724 /* If we have no actual push instructions, or shouldn't use them,
2725 make space for all args right now. */
2726 else if (adjusted_args_size
.var
!= 0)
2728 if (old_stack_level
== 0)
2730 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
2731 old_pending_adj
= pending_stack_adjust
;
2732 pending_stack_adjust
= 0;
2733 /* stack_arg_under_construction says whether a stack arg is
2734 being constructed at the old stack level. Pushing the stack
2735 gets a clean outgoing argument block. */
2736 old_stack_arg_under_construction
= stack_arg_under_construction
;
2737 stack_arg_under_construction
= 0;
2739 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2743 /* Note that we must go through the motions of allocating an argument
2744 block even if the size is zero because we may be storing args
2745 in the area reserved for register arguments, which may be part of
2748 int needed
= adjusted_args_size
.constant
;
2750 /* Store the maximum argument space used. It will be pushed by
2751 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2754 if (needed
> current_function_outgoing_args_size
)
2755 current_function_outgoing_args_size
= needed
;
2757 if (must_preallocate
)
2759 if (ACCUMULATE_OUTGOING_ARGS
)
2761 /* Since the stack pointer will never be pushed, it is
2762 possible for the evaluation of a parm to clobber
2763 something we have already written to the stack.
2764 Since most function calls on RISC machines do not use
2765 the stack, this is uncommon, but must work correctly.
2767 Therefore, we save any area of the stack that was already
2768 written and that we are using. Here we set up to do this
2769 by making a new stack usage map from the old one. The
2770 actual save will be done by store_one_arg.
2772 Another approach might be to try to reorder the argument
2773 evaluations to avoid this conflicting stack usage. */
2775 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2776 /* Since we will be writing into the entire argument area,
2777 the map must be allocated for its entire size, not just
2778 the part that is the responsibility of the caller. */
2779 needed
+= reg_parm_stack_space
;
2782 #ifdef ARGS_GROW_DOWNWARD
2783 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2786 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2790 = (char *) alloca (highest_outgoing_arg_in_use
);
2792 if (initial_highest_arg_in_use
)
2793 memcpy (stack_usage_map
, initial_stack_usage_map
,
2794 initial_highest_arg_in_use
);
2796 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2797 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2798 (highest_outgoing_arg_in_use
2799 - initial_highest_arg_in_use
));
2802 /* The address of the outgoing argument list must not be
2803 copied to a register here, because argblock would be left
2804 pointing to the wrong place after the call to
2805 allocate_dynamic_stack_space below. */
2807 argblock
= virtual_outgoing_args_rtx
;
2811 if (inhibit_defer_pop
== 0)
2813 /* Try to reuse some or all of the pending_stack_adjust
2814 to get this space. */
2816 = (combine_pending_stack_adjustment_and_call
2817 (unadjusted_args_size
,
2818 &adjusted_args_size
,
2819 preferred_unit_stack_boundary
));
2821 /* combine_pending_stack_adjustment_and_call computes
2822 an adjustment before the arguments are allocated.
2823 Account for them and see whether or not the stack
2824 needs to go up or down. */
2825 needed
= unadjusted_args_size
- needed
;
2829 /* We're releasing stack space. */
2830 /* ??? We can avoid any adjustment at all if we're
2831 already aligned. FIXME. */
2832 pending_stack_adjust
= -needed
;
2833 do_pending_stack_adjust ();
2837 /* We need to allocate space. We'll do that in
2838 push_block below. */
2839 pending_stack_adjust
= 0;
2842 /* Special case this because overhead of `push_block' in
2843 this case is non-trivial. */
2845 argblock
= virtual_outgoing_args_rtx
;
2847 argblock
= push_block (GEN_INT (needed
), 0, 0);
2849 /* We only really need to call `copy_to_reg' in the case
2850 where push insns are going to be used to pass ARGBLOCK
2851 to a function call in ARGS. In that case, the stack
2852 pointer changes value from the allocation point to the
2853 call point, and hence the value of
2854 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2855 as well always do it. */
2856 argblock
= copy_to_reg (argblock
);
2858 /* The save/restore code in store_one_arg handles all
2859 cases except one: a constructor call (including a C
2860 function returning a BLKmode struct) to initialize
2862 if (stack_arg_under_construction
)
2864 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2865 rtx push_size
= GEN_INT (reg_parm_stack_space
2866 + adjusted_args_size
.constant
);
2868 rtx push_size
= GEN_INT (adjusted_args_size
.constant
);
2870 if (old_stack_level
== 0)
2872 emit_stack_save (SAVE_BLOCK
, &old_stack_level
,
2874 old_pending_adj
= pending_stack_adjust
;
2875 pending_stack_adjust
= 0;
2876 /* stack_arg_under_construction says whether a stack
2877 arg is being constructed at the old stack level.
2878 Pushing the stack gets a clean outgoing argument
2880 old_stack_arg_under_construction
2881 = stack_arg_under_construction
;
2882 stack_arg_under_construction
= 0;
2883 /* Make a new map for the new argument list. */
2884 stack_usage_map
= (char *)
2885 alloca (highest_outgoing_arg_in_use
);
2886 memset (stack_usage_map
, 0, highest_outgoing_arg_in_use
);
2887 highest_outgoing_arg_in_use
= 0;
2889 allocate_dynamic_stack_space (push_size
, NULL_RTX
,
2892 /* If argument evaluation might modify the stack pointer,
2893 copy the address of the argument list to a register. */
2894 for (i
= 0; i
< num_actuals
; i
++)
2895 if (args
[i
].pass_on_stack
)
2897 argblock
= copy_addr_to_reg (argblock
);
2904 compute_argument_addresses (args
, argblock
, num_actuals
);
2906 /* If we push args individually in reverse order, perform stack alignment
2907 before the first push (the last arg). */
2908 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2909 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2911 /* When the stack adjustment is pending, we get better code
2912 by combining the adjustments. */
2913 if (pending_stack_adjust
2914 && ! (flags
& ECF_LIBCALL_BLOCK
)
2915 && ! inhibit_defer_pop
)
2917 pending_stack_adjust
2918 = (combine_pending_stack_adjustment_and_call
2919 (unadjusted_args_size
,
2920 &adjusted_args_size
,
2921 preferred_unit_stack_boundary
));
2922 do_pending_stack_adjust ();
2924 else if (argblock
== 0)
2925 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2926 - unadjusted_args_size
));
2928 /* Now that the stack is properly aligned, pops can't safely
2929 be deferred during the evaluation of the arguments. */
2932 funexp
= rtx_for_function_call (fndecl
, exp
);
2934 /* Figure out the register where the value, if any, will come back. */
2936 if (TYPE_MODE (TREE_TYPE (exp
)) != VOIDmode
2937 && ! structure_value_addr
)
2939 if (pcc_struct_value
)
2940 valreg
= hard_function_value (build_pointer_type (TREE_TYPE (exp
)),
2941 fndecl
, (pass
== 0));
2943 valreg
= hard_function_value (TREE_TYPE (exp
), fndecl
, (pass
== 0));
2946 /* Precompute all register parameters. It isn't safe to compute anything
2947 once we have started filling any specific hard regs. */
2948 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2950 #ifdef REG_PARM_STACK_SPACE
2951 /* Save the fixed argument area if it's part of the caller's frame and
2952 is clobbered by argument setup for this call. */
2953 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2954 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2955 &low_to_save
, &high_to_save
);
2958 /* Now store (and compute if necessary) all non-register parms.
2959 These come before register parms, since they can require block-moves,
2960 which could clobber the registers used for register parms.
2961 Parms which have partial registers are not stored here,
2962 but we do preallocate space here if they want that. */
2964 for (i
= 0; i
< num_actuals
; i
++)
2965 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2967 rtx before_arg
= get_last_insn ();
2969 if (store_one_arg (&args
[i
], argblock
, flags
,
2970 adjusted_args_size
.var
!= 0,
2971 reg_parm_stack_space
)
2973 && check_sibcall_argument_overlap (before_arg
,
2975 sibcall_failure
= 1;
2978 /* If we have a parm that is passed in registers but not in memory
2979 and whose alignment does not permit a direct copy into registers,
2980 make a group of pseudos that correspond to each register that we
2982 if (STRICT_ALIGNMENT
)
2983 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2985 /* Now store any partially-in-registers parm.
2986 This is the last place a block-move can happen. */
2988 for (i
= 0; i
< num_actuals
; i
++)
2989 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2991 rtx before_arg
= get_last_insn ();
2993 if (store_one_arg (&args
[i
], argblock
, flags
,
2994 adjusted_args_size
.var
!= 0,
2995 reg_parm_stack_space
)
2997 && check_sibcall_argument_overlap (before_arg
,
2999 sibcall_failure
= 1;
3002 /* If we pushed args in forward order, perform stack alignment
3003 after pushing the last arg. */
3004 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
3005 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
3006 - unadjusted_args_size
));
3008 /* If register arguments require space on the stack and stack space
3009 was not preallocated, allocate stack space here for arguments
3010 passed in registers. */
3011 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3012 if (!ACCUMULATE_OUTGOING_ARGS
3013 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
3014 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
3017 /* Pass the function the address in which to return a
3019 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
3021 emit_move_insn (struct_value_rtx
,
3023 force_operand (structure_value_addr
,
3026 if (GET_CODE (struct_value_rtx
) == REG
)
3027 use_reg (&call_fusage
, struct_value_rtx
);
3030 funexp
= prepare_call_address (funexp
, fndecl
, &call_fusage
,
3031 reg_parm_seen
, pass
== 0);
3033 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
);
3035 /* Perform postincrements before actually calling the function. */
3038 /* Save a pointer to the last insn before the call, so that we can
3039 later safely search backwards to find the CALL_INSN. */
3040 before_call
= get_last_insn ();
3042 /* Set up next argument register. For sibling calls on machines
3043 with register windows this should be the incoming register. */
3044 #ifdef FUNCTION_INCOMING_ARG
3046 next_arg_reg
= FUNCTION_INCOMING_ARG (args_so_far
, VOIDmode
,
3050 next_arg_reg
= FUNCTION_ARG (args_so_far
, VOIDmode
,
3053 /* All arguments and registers used for the call must be set up by
3056 /* Stack must be properly aligned now. */
3057 if (pass
&& stack_pointer_delta
% preferred_unit_stack_boundary
)
3060 /* Generate the actual call instruction. */
3061 emit_call_1 (funexp
, fndecl
, funtype
, unadjusted_args_size
,
3062 adjusted_args_size
.constant
, struct_value_size
,
3063 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
3064 flags
, & args_so_far
);
3066 /* Verify that we've deallocated all the stack we used. */
3068 && old_stack_allocated
!= stack_pointer_delta
- pending_stack_adjust
)
3071 /* If call is cse'able, make appropriate pair of reg-notes around it.
3072 Test valreg so we don't crash; may safely ignore `const'
3073 if return type is void. Disable for PARALLEL return values, because
3074 we have no way to move such values into a pseudo register. */
3075 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
3079 if (valreg
== 0 || GET_CODE (valreg
) == PARALLEL
)
3081 insns
= get_insns ();
3088 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
3090 /* Mark the return value as a pointer if needed. */
3091 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
3092 mark_reg_pointer (temp
,
3093 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp
))));
3095 /* Construct an "equal form" for the value which mentions all the
3096 arguments in order as well as the function name. */
3097 for (i
= 0; i
< num_actuals
; i
++)
3098 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3099 args
[i
].initial_value
, note
);
3100 note
= gen_rtx_EXPR_LIST (VOIDmode
, funexp
, note
);
3102 insns
= get_insns ();
3105 if (flags
& ECF_PURE
)
3106 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3107 gen_rtx_USE (VOIDmode
,
3108 gen_rtx_MEM (BLKmode
,
3109 gen_rtx_SCRATCH (VOIDmode
))),
3112 emit_libcall_block (insns
, temp
, valreg
, note
);
3117 else if (pass
&& (flags
& ECF_MALLOC
))
3119 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
3122 /* The return value from a malloc-like function is a pointer. */
3123 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
3124 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
3126 emit_move_insn (temp
, valreg
);
3128 /* The return value from a malloc-like function can not alias
3130 last
= get_last_insn ();
3132 gen_rtx_EXPR_LIST (REG_NOALIAS
, temp
, REG_NOTES (last
));
3134 /* Write out the sequence. */
3135 insns
= get_insns ();
3141 /* For calls to `setjmp', etc., inform flow.c it should complain
3142 if nonvolatile values are live. For functions that cannot return,
3143 inform flow that control does not fall through. */
3145 if ((flags
& (ECF_NORETURN
| ECF_LONGJMP
)) || pass
== 0)
3147 /* The barrier must be emitted
3148 immediately after the CALL_INSN. Some ports emit more
3149 than just a CALL_INSN above, so we must search for it here. */
3151 rtx last
= get_last_insn ();
3152 while (GET_CODE (last
) != CALL_INSN
)
3154 last
= PREV_INSN (last
);
3155 /* There was no CALL_INSN? */
3156 if (last
== before_call
)
3160 emit_barrier_after (last
);
3163 if (flags
& ECF_LONGJMP
)
3164 current_function_calls_longjmp
= 1;
3166 /* If this function is returning into a memory location marked as
3167 readonly, it means it is initializing that location. But we normally
3168 treat functions as not clobbering such locations, so we need to
3169 specify that this one does. */
3170 if (target
!= 0 && GET_CODE (target
) == MEM
3171 && structure_value_addr
!= 0 && RTX_UNCHANGING_P (target
))
3172 emit_insn (gen_rtx_CLOBBER (VOIDmode
, target
));
3174 /* If value type not void, return an rtx for the value. */
3176 /* If there are cleanups to be called, don't use a hard reg as target.
3177 We need to double check this and see if it matters anymore. */
3178 if (any_pending_cleanups (1))
3180 if (target
&& REG_P (target
)
3181 && REGNO (target
) < FIRST_PSEUDO_REGISTER
)
3183 sibcall_failure
= 1;
3186 if (TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
3188 target
= const0_rtx
;
3189 else if (structure_value_addr
)
3191 if (target
== 0 || GET_CODE (target
) != MEM
)
3194 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
3195 memory_address (TYPE_MODE (TREE_TYPE (exp
)),
3196 structure_value_addr
));
3197 set_mem_attributes (target
, exp
, 1);
3200 else if (pcc_struct_value
)
3202 /* This is the special C++ case where we need to
3203 know what the true target was. We take care to
3204 never use this value more than once in one expression. */
3205 target
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
3206 copy_to_reg (valreg
));
3207 set_mem_attributes (target
, exp
, 1);
3209 /* Handle calls that return values in multiple non-contiguous locations.
3210 The Irix 6 ABI has examples of this. */
3211 else if (GET_CODE (valreg
) == PARALLEL
)
3215 /* This will only be assigned once, so it can be readonly. */
3216 tree nt
= build_qualified_type (TREE_TYPE (exp
),
3217 (TYPE_QUALS (TREE_TYPE (exp
))
3218 | TYPE_QUAL_CONST
));
3220 target
= assign_temp (nt
, 0, 1, 1);
3221 preserve_temp_slots (target
);
3224 if (! rtx_equal_p (target
, valreg
))
3225 emit_group_store (target
, valreg
,
3226 int_size_in_bytes (TREE_TYPE (exp
)));
3228 /* We can not support sibling calls for this case. */
3229 sibcall_failure
= 1;
3232 && GET_MODE (target
) == TYPE_MODE (TREE_TYPE (exp
))
3233 && GET_MODE (target
) == GET_MODE (valreg
))
3235 /* TARGET and VALREG cannot be equal at this point because the
3236 latter would not have REG_FUNCTION_VALUE_P true, while the
3237 former would if it were referring to the same register.
3239 If they refer to the same register, this move will be a no-op,
3240 except when function inlining is being done. */
3241 emit_move_insn (target
, valreg
);
3243 else if (TYPE_MODE (TREE_TYPE (exp
)) == BLKmode
)
3245 target
= copy_blkmode_from_reg (target
, valreg
, TREE_TYPE (exp
));
3247 /* We can not support sibling calls for this case. */
3248 sibcall_failure
= 1;
3251 target
= copy_to_reg (valreg
);
3253 #ifdef PROMOTE_FUNCTION_RETURN
3254 /* If we promoted this return value, make the proper SUBREG. TARGET
3255 might be const0_rtx here, so be careful. */
3256 if (GET_CODE (target
) == REG
3257 && TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
3258 && GET_MODE (target
) != TYPE_MODE (TREE_TYPE (exp
)))
3260 tree type
= TREE_TYPE (exp
);
3261 int unsignedp
= TREE_UNSIGNED (type
);
3264 /* If we don't promote as expected, something is wrong. */
3265 if (GET_MODE (target
)
3266 != promote_mode (type
, TYPE_MODE (type
), &unsignedp
, 1))
3269 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
3270 && GET_MODE_SIZE (GET_MODE (target
))
3271 > GET_MODE_SIZE (TYPE_MODE (type
)))
3273 offset
= GET_MODE_SIZE (GET_MODE (target
))
3274 - GET_MODE_SIZE (TYPE_MODE (type
));
3275 if (! BYTES_BIG_ENDIAN
)
3276 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
3277 else if (! WORDS_BIG_ENDIAN
)
3278 offset
%= UNITS_PER_WORD
;
3280 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
3281 SUBREG_PROMOTED_VAR_P (target
) = 1;
3282 SUBREG_PROMOTED_UNSIGNED_SET (target
, unsignedp
);
3286 /* If size of args is variable or this was a constructor call for a stack
3287 argument, restore saved stack-pointer value. */
3289 if (old_stack_level
&& ! (flags
& ECF_SP_DEPRESSED
))
3291 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
3292 pending_stack_adjust
= old_pending_adj
;
3293 stack_arg_under_construction
= old_stack_arg_under_construction
;
3294 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3295 stack_usage_map
= initial_stack_usage_map
;
3296 sibcall_failure
= 1;
3298 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
3300 #ifdef REG_PARM_STACK_SPACE
3303 restore_fixed_argument_area (save_area
, argblock
,
3304 high_to_save
, low_to_save
);
3308 /* If we saved any argument areas, restore them. */
3309 for (i
= 0; i
< num_actuals
; i
++)
3310 if (args
[i
].save_area
)
3312 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
3314 = gen_rtx_MEM (save_mode
,
3315 memory_address (save_mode
,
3316 XEXP (args
[i
].stack_slot
, 0)));
3318 if (save_mode
!= BLKmode
)
3319 emit_move_insn (stack_area
, args
[i
].save_area
);
3321 emit_block_move (stack_area
, args
[i
].save_area
,
3322 GEN_INT (args
[i
].size
.constant
),
3323 BLOCK_OP_CALL_PARM
);
3326 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3327 stack_usage_map
= initial_stack_usage_map
;
3330 /* If this was alloca, record the new stack level for nonlocal gotos.
3331 Check for the handler slots since we might not have a save area
3332 for non-local gotos. */
3334 if ((flags
& ECF_MAY_BE_ALLOCA
) && nonlocal_goto_handler_slots
!= 0)
3335 emit_stack_save (SAVE_NONLOCAL
, &nonlocal_goto_stack_level
, NULL_RTX
);
3337 /* Free up storage we no longer need. */
3338 for (i
= 0; i
< num_actuals
; ++i
)
3339 if (args
[i
].aligned_regs
)
3340 free (args
[i
].aligned_regs
);
3344 /* Undo the fake expand_start_target_temps we did earlier. If
3345 there had been any cleanups created, we've already set
3347 expand_end_target_temps ();
3350 insns
= get_insns ();
3355 tail_call_insns
= insns
;
3357 /* Restore the pending stack adjustment now that we have
3358 finished generating the sibling call sequence. */
3360 pending_stack_adjust
= save_pending_stack_adjust
;
3361 stack_pointer_delta
= save_stack_pointer_delta
;
3363 /* Prepare arg structure for next iteration. */
3364 for (i
= 0; i
< num_actuals
; i
++)
3367 args
[i
].aligned_regs
= 0;
3371 sbitmap_free (stored_args_map
);
3374 normal_call_insns
= insns
;
3376 /* If something prevents making this a sibling call,
3377 zero out the sequence. */
3378 if (sibcall_failure
)
3379 tail_call_insns
= NULL_RTX
;
3382 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3383 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3384 can happen if the arguments to this function call an inline
3385 function who's expansion contains another CALL_PLACEHOLDER.
3387 If there are any C_Ps in any of these sequences, replace them
3388 with their normal call. */
3390 for (insn
= normal_call_insns
; insn
; insn
= NEXT_INSN (insn
))
3391 if (GET_CODE (insn
) == CALL_INSN
3392 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3393 replace_call_placeholder (insn
, sibcall_use_normal
);
3395 for (insn
= tail_call_insns
; insn
; insn
= NEXT_INSN (insn
))
3396 if (GET_CODE (insn
) == CALL_INSN
3397 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3398 replace_call_placeholder (insn
, sibcall_use_normal
);
3400 for (insn
= tail_recursion_insns
; insn
; insn
= NEXT_INSN (insn
))
3401 if (GET_CODE (insn
) == CALL_INSN
3402 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3403 replace_call_placeholder (insn
, sibcall_use_normal
);
3405 /* If this was a potential tail recursion site, then emit a
3406 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3407 One of them will be selected later. */
3408 if (tail_recursion_insns
|| tail_call_insns
)
3410 /* The tail recursion label must be kept around. We could expose
3411 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3412 and makes determining true tail recursion sites difficult.
3414 So we set LABEL_PRESERVE_P here, then clear it when we select
3415 one of the call sequences after rtl generation is complete. */
3416 if (tail_recursion_insns
)
3417 LABEL_PRESERVE_P (tail_recursion_label
) = 1;
3418 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode
, normal_call_insns
,
3420 tail_recursion_insns
,
3421 tail_recursion_label
));
3424 emit_insn (normal_call_insns
);
3426 currently_expanding_call
--;
3428 /* If this function returns with the stack pointer depressed, ensure
3429 this block saves and restores the stack pointer, show it was
3430 changed, and adjust for any outgoing arg space. */
3431 if (flags
& ECF_SP_DEPRESSED
)
3433 clear_pending_stack_adjust ();
3434 emit_insn (gen_rtx (CLOBBER
, VOIDmode
, stack_pointer_rtx
));
3435 emit_move_insn (virtual_stack_dynamic_rtx
, stack_pointer_rtx
);
3436 save_stack_pointer ();
3442 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3443 The RETVAL parameter specifies whether return value needs to be saved, other
3444 parameters are documented in the emit_library_call function below. */
3447 emit_library_call_value_1 (retval
, orgfun
, value
, fn_type
, outmode
, nargs
, p
)
3451 enum libcall_type fn_type
;
3452 enum machine_mode outmode
;
3456 /* Total size in bytes of all the stack-parms scanned so far. */
3457 struct args_size args_size
;
3458 /* Size of arguments before any adjustments (such as rounding). */
3459 struct args_size original_args_size
;
3464 struct args_size alignment_pad
;
3466 CUMULATIVE_ARGS args_so_far
;
3470 enum machine_mode mode
;
3473 struct args_size offset
;
3474 struct args_size size
;
3478 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3479 rtx call_fusage
= 0;
3482 int pcc_struct_value
= 0;
3483 int struct_value_size
= 0;
3485 int reg_parm_stack_space
= 0;
3488 tree tfom
; /* type_for_mode (outmode, 0) */
3490 #ifdef REG_PARM_STACK_SPACE
3491 /* Define the boundary of the register parm stack space that needs to be
3493 int low_to_save
= -1, high_to_save
= 0;
3494 rtx save_area
= 0; /* Place that it is saved. */
3497 /* Size of the stack reserved for parameter registers. */
3498 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3499 char *initial_stack_usage_map
= stack_usage_map
;
3501 #ifdef REG_PARM_STACK_SPACE
3502 #ifdef MAYBE_REG_PARM_STACK_SPACE
3503 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
3505 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3509 /* By default, library functions can not throw. */
3510 flags
= ECF_NOTHROW
;
3522 case LCT_CONST_MAKE_BLOCK
:
3523 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
3525 case LCT_PURE_MAKE_BLOCK
:
3526 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
3529 flags
|= ECF_NORETURN
;
3532 flags
= ECF_NORETURN
;
3534 case LCT_ALWAYS_RETURN
:
3535 flags
= ECF_ALWAYS_RETURN
;
3537 case LCT_RETURNS_TWICE
:
3538 flags
= ECF_RETURNS_TWICE
;
3543 /* Ensure current function's preferred stack boundary is at least
3545 if (cfun
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3546 cfun
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3548 /* If this kind of value comes back in memory,
3549 decide where in memory it should come back. */
3550 if (outmode
!= VOIDmode
)
3552 tfom
= (*lang_hooks
.types
.type_for_mode
) (outmode
, 0);
3553 if (aggregate_value_p (tfom
))
3555 #ifdef PCC_STATIC_STRUCT_RETURN
3557 = hard_function_value (build_pointer_type (tfom
), 0, 0);
3558 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3559 pcc_struct_value
= 1;
3561 value
= gen_reg_rtx (outmode
);
3562 #else /* not PCC_STATIC_STRUCT_RETURN */
3563 struct_value_size
= GET_MODE_SIZE (outmode
);
3564 if (value
!= 0 && GET_CODE (value
) == MEM
)
3567 mem_value
= assign_temp (tfom
, 0, 1, 1);
3569 /* This call returns a big structure. */
3570 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3574 tfom
= void_type_node
;
3576 /* ??? Unfinished: must pass the memory address as an argument. */
3578 /* Copy all the libcall-arguments out of the varargs data
3579 and into a vector ARGVEC.
3581 Compute how to pass each argument. We only support a very small subset
3582 of the full argument passing conventions to limit complexity here since
3583 library functions shouldn't have many args. */
3585 argvec
= (struct arg
*) alloca ((nargs
+ 1) * sizeof (struct arg
));
3586 memset ((char *) argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3588 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3589 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3591 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0);
3594 args_size
.constant
= 0;
3599 /* Now we are about to start emitting insns that can be deleted
3600 if a libcall is deleted. */
3601 if (flags
& ECF_LIBCALL_BLOCK
)
3606 /* If there's a structure value address to be passed,
3607 either pass it in the special place, or pass it as an extra argument. */
3608 if (mem_value
&& struct_value_rtx
== 0 && ! pcc_struct_value
)
3610 rtx addr
= XEXP (mem_value
, 0);
3613 /* Make sure it is a reasonable operand for a move or push insn. */
3614 if (GET_CODE (addr
) != REG
&& GET_CODE (addr
) != MEM
3615 && ! (CONSTANT_P (addr
) && LEGITIMATE_CONSTANT_P (addr
)))
3616 addr
= force_operand (addr
, NULL_RTX
);
3618 argvec
[count
].value
= addr
;
3619 argvec
[count
].mode
= Pmode
;
3620 argvec
[count
].partial
= 0;
3622 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, Pmode
, NULL_TREE
, 1);
3623 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3624 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, Pmode
, NULL_TREE
, 1))
3628 locate_and_pad_parm (Pmode
, NULL_TREE
,
3629 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3632 argvec
[count
].reg
!= 0,
3634 NULL_TREE
, &args_size
, &argvec
[count
].offset
,
3635 &argvec
[count
].size
, &alignment_pad
);
3637 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3638 || reg_parm_stack_space
> 0)
3639 args_size
.constant
+= argvec
[count
].size
.constant
;
3641 FUNCTION_ARG_ADVANCE (args_so_far
, Pmode
, (tree
) 0, 1);
3646 for (; count
< nargs
; count
++)
3648 rtx val
= va_arg (p
, rtx
);
3649 enum machine_mode mode
= va_arg (p
, enum machine_mode
);
3651 /* We cannot convert the arg value to the mode the library wants here;
3652 must do it earlier where we know the signedness of the arg. */
3654 || (GET_MODE (val
) != mode
&& GET_MODE (val
) != VOIDmode
))
3657 /* On some machines, there's no way to pass a float to a library fcn.
3658 Pass it as a double instead. */
3659 #ifdef LIBGCC_NEEDS_DOUBLE
3660 if (LIBGCC_NEEDS_DOUBLE
&& mode
== SFmode
)
3661 val
= convert_modes (DFmode
, SFmode
, val
, 0), mode
= DFmode
;
3664 /* There's no need to call protect_from_queue, because
3665 either emit_move_insn or emit_push_insn will do that. */
3667 /* Make sure it is a reasonable operand for a move or push insn. */
3668 if (GET_CODE (val
) != REG
&& GET_CODE (val
) != MEM
3669 && ! (CONSTANT_P (val
) && LEGITIMATE_CONSTANT_P (val
)))
3670 val
= force_operand (val
, NULL_RTX
);
3672 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3673 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far
, mode
, NULL_TREE
, 1))
3677 #ifdef FUNCTION_ARG_CALLEE_COPIES
3678 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far
, mode
,
3683 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3684 functions, so we have to pretend this isn't such a function. */
3685 if (flags
& ECF_LIBCALL_BLOCK
)
3687 rtx insns
= get_insns ();
3691 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3693 /* If this was a CONST function, it is now PURE since
3694 it now reads memory. */
3695 if (flags
& ECF_CONST
)
3697 flags
&= ~ECF_CONST
;
3701 if (GET_MODE (val
) == MEM
&& ! must_copy
)
3705 slot
= assign_temp ((*lang_hooks
.types
.type_for_mode
) (mode
, 0),
3707 emit_move_insn (slot
, val
);
3711 tree type
= (*lang_hooks
.types
.type_for_mode
) (mode
, 0);
3713 slot
= gen_rtx_MEM (mode
,
3714 expand_expr (build1 (ADDR_EXPR
,
3717 make_tree (type
, val
)),
3718 NULL_RTX
, VOIDmode
, 0));
3721 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3722 gen_rtx_USE (VOIDmode
, slot
),
3725 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3726 gen_rtx_CLOBBER (VOIDmode
,
3731 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3735 argvec
[count
].value
= val
;
3736 argvec
[count
].mode
= mode
;
3738 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, mode
, NULL_TREE
, 1);
3740 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3741 argvec
[count
].partial
3742 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, mode
, NULL_TREE
, 1);
3744 argvec
[count
].partial
= 0;
3747 locate_and_pad_parm (mode
, NULL_TREE
,
3748 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3751 argvec
[count
].reg
!= 0,
3753 NULL_TREE
, &args_size
, &argvec
[count
].offset
,
3754 &argvec
[count
].size
, &alignment_pad
);
3756 if (argvec
[count
].size
.var
)
3759 if (reg_parm_stack_space
== 0 && argvec
[count
].partial
)
3760 argvec
[count
].size
.constant
-= argvec
[count
].partial
* UNITS_PER_WORD
;
3762 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3763 || reg_parm_stack_space
> 0)
3764 args_size
.constant
+= argvec
[count
].size
.constant
;
3766 FUNCTION_ARG_ADVANCE (args_so_far
, mode
, (tree
) 0, 1);
3769 #ifdef FINAL_REG_PARM_STACK_SPACE
3770 reg_parm_stack_space
= FINAL_REG_PARM_STACK_SPACE (args_size
.constant
,
3773 /* If this machine requires an external definition for library
3774 functions, write one out. */
3775 assemble_external_libcall (fun
);
3777 original_args_size
= args_size
;
3778 args_size
.constant
= (((args_size
.constant
3779 + stack_pointer_delta
3783 - stack_pointer_delta
);
3785 args_size
.constant
= MAX (args_size
.constant
,
3786 reg_parm_stack_space
);
3788 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3789 args_size
.constant
-= reg_parm_stack_space
;
3792 if (args_size
.constant
> current_function_outgoing_args_size
)
3793 current_function_outgoing_args_size
= args_size
.constant
;
3795 if (ACCUMULATE_OUTGOING_ARGS
)
3797 /* Since the stack pointer will never be pushed, it is possible for
3798 the evaluation of a parm to clobber something we have already
3799 written to the stack. Since most function calls on RISC machines
3800 do not use the stack, this is uncommon, but must work correctly.
3802 Therefore, we save any area of the stack that was already written
3803 and that we are using. Here we set up to do this by making a new
3804 stack usage map from the old one.
3806 Another approach might be to try to reorder the argument
3807 evaluations to avoid this conflicting stack usage. */
3809 needed
= args_size
.constant
;
3811 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3812 /* Since we will be writing into the entire argument area, the
3813 map must be allocated for its entire size, not just the part that
3814 is the responsibility of the caller. */
3815 needed
+= reg_parm_stack_space
;
3818 #ifdef ARGS_GROW_DOWNWARD
3819 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3822 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3825 stack_usage_map
= (char *) alloca (highest_outgoing_arg_in_use
);
3827 if (initial_highest_arg_in_use
)
3828 memcpy (stack_usage_map
, initial_stack_usage_map
,
3829 initial_highest_arg_in_use
);
3831 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3832 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3833 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3836 /* We must be careful to use virtual regs before they're instantiated,
3837 and real regs afterwards. Loop optimization, for example, can create
3838 new libcalls after we've instantiated the virtual regs, and if we
3839 use virtuals anyway, they won't match the rtl patterns. */
3841 if (virtuals_instantiated
)
3842 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3844 argblock
= virtual_outgoing_args_rtx
;
3849 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3852 /* If we push args individually in reverse order, perform stack alignment
3853 before the first push (the last arg). */
3854 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3855 anti_adjust_stack (GEN_INT (args_size
.constant
3856 - original_args_size
.constant
));
3858 if (PUSH_ARGS_REVERSED
)
3869 #ifdef REG_PARM_STACK_SPACE
3870 if (ACCUMULATE_OUTGOING_ARGS
)
3872 /* The argument list is the property of the called routine and it
3873 may clobber it. If the fixed area has been used for previous
3874 parameters, we must save and restore it.
3876 Here we compute the boundary of the that needs to be saved, if any. */
3878 #ifdef ARGS_GROW_DOWNWARD
3879 for (count
= 0; count
< reg_parm_stack_space
+ 1; count
++)
3881 for (count
= 0; count
< reg_parm_stack_space
; count
++)
3884 if (count
>= highest_outgoing_arg_in_use
3885 || stack_usage_map
[count
] == 0)
3888 if (low_to_save
== -1)
3889 low_to_save
= count
;
3891 high_to_save
= count
;
3894 if (low_to_save
>= 0)
3896 int num_to_save
= high_to_save
- low_to_save
+ 1;
3897 enum machine_mode save_mode
3898 = mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
3901 /* If we don't have the required alignment, must do this in BLKmode. */
3902 if ((low_to_save
& (MIN (GET_MODE_SIZE (save_mode
),
3903 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
3904 save_mode
= BLKmode
;
3906 #ifdef ARGS_GROW_DOWNWARD
3907 stack_area
= gen_rtx_MEM (save_mode
,
3908 memory_address (save_mode
,
3909 plus_constant (argblock
,
3912 stack_area
= gen_rtx_MEM (save_mode
,
3913 memory_address (save_mode
,
3914 plus_constant (argblock
,
3917 if (save_mode
== BLKmode
)
3919 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
3920 set_mem_align (save_area
, PARM_BOUNDARY
);
3921 emit_block_move (save_area
, stack_area
, GEN_INT (num_to_save
),
3922 BLOCK_OP_CALL_PARM
);
3926 save_area
= gen_reg_rtx (save_mode
);
3927 emit_move_insn (save_area
, stack_area
);
3933 /* Push the args that need to be pushed. */
3935 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3936 are to be pushed. */
3937 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3939 enum machine_mode mode
= argvec
[argnum
].mode
;
3940 rtx val
= argvec
[argnum
].value
;
3941 rtx reg
= argvec
[argnum
].reg
;
3942 int partial
= argvec
[argnum
].partial
;
3943 int lower_bound
= 0, upper_bound
= 0, i
;
3945 if (! (reg
!= 0 && partial
== 0))
3947 if (ACCUMULATE_OUTGOING_ARGS
)
3949 /* If this is being stored into a pre-allocated, fixed-size,
3950 stack area, save any previous data at that location. */
3952 #ifdef ARGS_GROW_DOWNWARD
3953 /* stack_slot is negative, but we want to index stack_usage_map
3954 with positive values. */
3955 upper_bound
= -argvec
[argnum
].offset
.constant
+ 1;
3956 lower_bound
= upper_bound
- argvec
[argnum
].size
.constant
;
3958 lower_bound
= argvec
[argnum
].offset
.constant
;
3959 upper_bound
= lower_bound
+ argvec
[argnum
].size
.constant
;
3962 for (i
= lower_bound
; i
< upper_bound
; i
++)
3963 if (stack_usage_map
[i
]
3964 /* Don't store things in the fixed argument area at this
3965 point; it has already been saved. */
3966 && i
> reg_parm_stack_space
)
3969 if (i
!= upper_bound
)
3971 /* We need to make a save area. See what mode we can make
3973 enum machine_mode save_mode
3974 = mode_for_size (argvec
[argnum
].size
.constant
3982 plus_constant (argblock
,
3983 argvec
[argnum
].offset
.constant
)));
3984 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3986 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3990 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, PARM_BOUNDARY
,
3991 partial
, reg
, 0, argblock
,
3992 GEN_INT (argvec
[argnum
].offset
.constant
),
3993 reg_parm_stack_space
, ARGS_SIZE_RTX (alignment_pad
));
3995 /* Now mark the segment we just used. */
3996 if (ACCUMULATE_OUTGOING_ARGS
)
3997 for (i
= lower_bound
; i
< upper_bound
; i
++)
3998 stack_usage_map
[i
] = 1;
4004 /* If we pushed args in forward order, perform stack alignment
4005 after pushing the last arg. */
4006 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
4007 anti_adjust_stack (GEN_INT (args_size
.constant
4008 - original_args_size
.constant
));
4010 if (PUSH_ARGS_REVERSED
)
4015 fun
= prepare_call_address (fun
, NULL_TREE
, &call_fusage
, 0, 0);
4017 /* Now load any reg parms into their regs. */
4019 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4020 are to be pushed. */
4021 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
4023 rtx val
= argvec
[argnum
].value
;
4024 rtx reg
= argvec
[argnum
].reg
;
4025 int partial
= argvec
[argnum
].partial
;
4027 /* Handle calls that pass values in multiple non-contiguous
4028 locations. The PA64 has examples of this for library calls. */
4029 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
4030 emit_group_load (reg
, val
, GET_MODE_SIZE (GET_MODE (val
)));
4031 else if (reg
!= 0 && partial
== 0)
4032 emit_move_insn (reg
, val
);
4037 /* Any regs containing parms remain in use through the call. */
4038 for (count
= 0; count
< nargs
; count
++)
4040 rtx reg
= argvec
[count
].reg
;
4041 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
4042 use_group_regs (&call_fusage
, reg
);
4044 use_reg (&call_fusage
, reg
);
4047 /* Pass the function the address in which to return a structure value. */
4048 if (mem_value
!= 0 && struct_value_rtx
!= 0 && ! pcc_struct_value
)
4050 emit_move_insn (struct_value_rtx
,
4052 force_operand (XEXP (mem_value
, 0),
4054 if (GET_CODE (struct_value_rtx
) == REG
)
4055 use_reg (&call_fusage
, struct_value_rtx
);
4058 /* Don't allow popping to be deferred, since then
4059 cse'ing of library calls could delete a call and leave the pop. */
4061 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
4062 ? hard_libcall_value (outmode
) : NULL_RTX
);
4064 /* Stack must be properly aligned now. */
4065 if (stack_pointer_delta
& (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1))
4068 before_call
= get_last_insn ();
4070 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4071 will set inhibit_defer_pop to that value. */
4072 /* The return type is needed to decide how many bytes the function pops.
4073 Signedness plays no role in that, so for simplicity, we pretend it's
4074 always signed. We also assume that the list of arguments passed has
4075 no impact, so we pretend it is unknown. */
4078 get_identifier (XSTR (orgfun
, 0)),
4079 build_function_type (tfom
, NULL_TREE
),
4080 original_args_size
.constant
, args_size
.constant
,
4082 FUNCTION_ARG (args_so_far
, VOIDmode
, void_type_node
, 1),
4084 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, & args_so_far
);
4086 /* For calls to `setjmp', etc., inform flow.c it should complain
4087 if nonvolatile values are live. For functions that cannot return,
4088 inform flow that control does not fall through. */
4090 if (flags
& (ECF_NORETURN
| ECF_LONGJMP
))
4092 /* The barrier note must be emitted
4093 immediately after the CALL_INSN. Some ports emit more than
4094 just a CALL_INSN above, so we must search for it here. */
4096 rtx last
= get_last_insn ();
4097 while (GET_CODE (last
) != CALL_INSN
)
4099 last
= PREV_INSN (last
);
4100 /* There was no CALL_INSN? */
4101 if (last
== before_call
)
4105 emit_barrier_after (last
);
4108 /* Now restore inhibit_defer_pop to its actual original value. */
4111 /* If call is cse'able, make appropriate pair of reg-notes around it.
4112 Test valreg so we don't crash; may safely ignore `const'
4113 if return type is void. Disable for PARALLEL return values, because
4114 we have no way to move such values into a pseudo register. */
4115 if (flags
& ECF_LIBCALL_BLOCK
)
4119 if (valreg
== 0 || GET_CODE (valreg
) == PARALLEL
)
4121 insns
= get_insns ();
4128 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
4131 /* Construct an "equal form" for the value which mentions all the
4132 arguments in order as well as the function name. */
4133 for (i
= 0; i
< nargs
; i
++)
4134 note
= gen_rtx_EXPR_LIST (VOIDmode
, argvec
[i
].value
, note
);
4135 note
= gen_rtx_EXPR_LIST (VOIDmode
, fun
, note
);
4137 insns
= get_insns ();
4140 if (flags
& ECF_PURE
)
4141 note
= gen_rtx_EXPR_LIST (VOIDmode
,
4142 gen_rtx_USE (VOIDmode
,
4143 gen_rtx_MEM (BLKmode
,
4144 gen_rtx_SCRATCH (VOIDmode
))),
4147 emit_libcall_block (insns
, temp
, valreg
, note
);
4154 /* Copy the value to the right place. */
4155 if (outmode
!= VOIDmode
&& retval
)
4161 if (value
!= mem_value
)
4162 emit_move_insn (value
, mem_value
);
4164 else if (value
!= 0)
4165 emit_move_insn (value
, valreg
);
4170 if (ACCUMULATE_OUTGOING_ARGS
)
4172 #ifdef REG_PARM_STACK_SPACE
4175 enum machine_mode save_mode
= GET_MODE (save_area
);
4176 #ifdef ARGS_GROW_DOWNWARD
4178 = gen_rtx_MEM (save_mode
,
4179 memory_address (save_mode
,
4180 plus_constant (argblock
,
4184 = gen_rtx_MEM (save_mode
,
4185 memory_address (save_mode
,
4186 plus_constant (argblock
, low_to_save
)));
4189 set_mem_align (stack_area
, PARM_BOUNDARY
);
4190 if (save_mode
!= BLKmode
)
4191 emit_move_insn (stack_area
, save_area
);
4193 emit_block_move (stack_area
, save_area
,
4194 GEN_INT (high_to_save
- low_to_save
+ 1),
4195 BLOCK_OP_CALL_PARM
);
4199 /* If we saved any argument areas, restore them. */
4200 for (count
= 0; count
< nargs
; count
++)
4201 if (argvec
[count
].save_area
)
4203 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
4205 = gen_rtx_MEM (save_mode
,
4208 plus_constant (argblock
,
4209 argvec
[count
].offset
.constant
)));
4211 emit_move_insn (stack_area
, argvec
[count
].save_area
);
4214 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4215 stack_usage_map
= initial_stack_usage_map
;
4222 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4223 (emitting the queue unless NO_QUEUE is nonzero),
4224 for a value of mode OUTMODE,
4225 with NARGS different arguments, passed as alternating rtx values
4226 and machine_modes to convert them to.
4227 The rtx values should have been passed through protect_from_queue already.
4229 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4230 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4231 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4232 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4233 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4234 or other LCT_ value for other types of library calls. */
4237 emit_library_call
VPARAMS((rtx orgfun
, enum libcall_type fn_type
,
4238 enum machine_mode outmode
, int nargs
, ...))
4241 VA_FIXEDARG (p
, rtx
, orgfun
);
4242 VA_FIXEDARG (p
, int, fn_type
);
4243 VA_FIXEDARG (p
, enum machine_mode
, outmode
);
4244 VA_FIXEDARG (p
, int, nargs
);
4246 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
4251 /* Like emit_library_call except that an extra argument, VALUE,
4252 comes second and says where to store the result.
4253 (If VALUE is zero, this function chooses a convenient way
4254 to return the value.
4256 This function returns an rtx for where the value is to be found.
4257 If VALUE is nonzero, VALUE is returned. */
4260 emit_library_call_value
VPARAMS((rtx orgfun
, rtx value
,
4261 enum libcall_type fn_type
,
4262 enum machine_mode outmode
, int nargs
, ...))
4267 VA_FIXEDARG (p
, rtx
, orgfun
);
4268 VA_FIXEDARG (p
, rtx
, value
);
4269 VA_FIXEDARG (p
, int, fn_type
);
4270 VA_FIXEDARG (p
, enum machine_mode
, outmode
);
4271 VA_FIXEDARG (p
, int, nargs
);
4273 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
4281 /* Store a single argument for a function call
4282 into the register or memory area where it must be passed.
4283 *ARG describes the argument value and where to pass it.
4285 ARGBLOCK is the address of the stack-block for all the arguments,
4286 or 0 on a machine where arguments are pushed individually.
4288 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4289 so must be careful about how the stack is used.
4291 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4292 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4293 that we need not worry about saving and restoring the stack.
4295 FNDECL is the declaration of the function we are calling.
4297 Return nonzero if this arg should cause sibcall failure,
4301 store_one_arg (arg
, argblock
, flags
, variable_size
, reg_parm_stack_space
)
4302 struct arg_data
*arg
;
4305 int variable_size ATTRIBUTE_UNUSED
;
4306 int reg_parm_stack_space
;
4308 tree pval
= arg
->tree_value
;
4312 int i
, lower_bound
= 0, upper_bound
= 0;
4313 int sibcall_failure
= 0;
4315 if (TREE_CODE (pval
) == ERROR_MARK
)
4318 /* Push a new temporary level for any temporaries we make for
4322 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4324 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4325 save any previous data at that location. */
4326 if (argblock
&& ! variable_size
&& arg
->stack
)
4328 #ifdef ARGS_GROW_DOWNWARD
4329 /* stack_slot is negative, but we want to index stack_usage_map
4330 with positive values. */
4331 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4332 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4336 lower_bound
= upper_bound
- arg
->size
.constant
;
4338 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4339 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4343 upper_bound
= lower_bound
+ arg
->size
.constant
;
4346 for (i
= lower_bound
; i
< upper_bound
; i
++)
4347 if (stack_usage_map
[i
]
4348 /* Don't store things in the fixed argument area at this point;
4349 it has already been saved. */
4350 && i
> reg_parm_stack_space
)
4353 if (i
!= upper_bound
)
4355 /* We need to make a save area. See what mode we can make it. */
4356 enum machine_mode save_mode
4357 = mode_for_size (arg
->size
.constant
* BITS_PER_UNIT
, MODE_INT
, 1);
4359 = gen_rtx_MEM (save_mode
,
4360 memory_address (save_mode
,
4361 XEXP (arg
->stack_slot
, 0)));
4363 if (save_mode
== BLKmode
)
4365 tree ot
= TREE_TYPE (arg
->tree_value
);
4366 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4367 | TYPE_QUAL_CONST
));
4369 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4370 preserve_temp_slots (arg
->save_area
);
4371 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4372 expr_size (arg
->tree_value
),
4373 BLOCK_OP_CALL_PARM
);
4377 arg
->save_area
= gen_reg_rtx (save_mode
);
4378 emit_move_insn (arg
->save_area
, stack_area
);
4382 /* Now that we have saved any slots that will be overwritten by this
4383 store, mark all slots this store will use. We must do this before
4384 we actually expand the argument since the expansion itself may
4385 trigger library calls which might need to use the same stack slot. */
4386 if (argblock
&& ! variable_size
&& arg
->stack
)
4387 for (i
= lower_bound
; i
< upper_bound
; i
++)
4388 stack_usage_map
[i
] = 1;
4391 /* If this isn't going to be placed on both the stack and in registers,
4392 set up the register and number of words. */
4393 if (! arg
->pass_on_stack
)
4395 if (flags
& ECF_SIBCALL
)
4396 reg
= arg
->tail_call_reg
;
4399 partial
= arg
->partial
;
4402 if (reg
!= 0 && partial
== 0)
4403 /* Being passed entirely in a register. We shouldn't be called in
4407 /* If this arg needs special alignment, don't load the registers
4409 if (arg
->n_aligned_regs
!= 0)
4412 /* If this is being passed partially in a register, we can't evaluate
4413 it directly into its stack slot. Otherwise, we can. */
4414 if (arg
->value
== 0)
4416 /* stack_arg_under_construction is nonzero if a function argument is
4417 being evaluated directly into the outgoing argument list and
4418 expand_call must take special action to preserve the argument list
4419 if it is called recursively.
4421 For scalar function arguments stack_usage_map is sufficient to
4422 determine which stack slots must be saved and restored. Scalar
4423 arguments in general have pass_on_stack == 0.
4425 If this argument is initialized by a function which takes the
4426 address of the argument (a C++ constructor or a C function
4427 returning a BLKmode structure), then stack_usage_map is
4428 insufficient and expand_call must push the stack around the
4429 function call. Such arguments have pass_on_stack == 1.
4431 Note that it is always safe to set stack_arg_under_construction,
4432 but this generates suboptimal code if set when not needed. */
4434 if (arg
->pass_on_stack
)
4435 stack_arg_under_construction
++;
4437 arg
->value
= expand_expr (pval
,
4439 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4440 ? NULL_RTX
: arg
->stack
,
4443 /* If we are promoting object (or for any other reason) the mode
4444 doesn't agree, convert the mode. */
4446 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4447 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4448 arg
->value
, arg
->unsignedp
);
4450 if (arg
->pass_on_stack
)
4451 stack_arg_under_construction
--;
4454 /* Don't allow anything left on stack from computation
4455 of argument to alloca. */
4456 if (flags
& ECF_MAY_BE_ALLOCA
)
4457 do_pending_stack_adjust ();
4459 if (arg
->value
== arg
->stack
)
4460 /* If the value is already in the stack slot, we are done. */
4462 else if (arg
->mode
!= BLKmode
)
4466 /* Argument is a scalar, not entirely passed in registers.
4467 (If part is passed in registers, arg->partial says how much
4468 and emit_push_insn will take care of putting it there.)
4470 Push it, and if its size is less than the
4471 amount of space allocated to it,
4472 also bump stack pointer by the additional space.
4473 Note that in C the default argument promotions
4474 will prevent such mismatches. */
4476 size
= GET_MODE_SIZE (arg
->mode
);
4477 /* Compute how much space the push instruction will push.
4478 On many machines, pushing a byte will advance the stack
4479 pointer by a halfword. */
4480 #ifdef PUSH_ROUNDING
4481 size
= PUSH_ROUNDING (size
);
4485 /* Compute how much space the argument should get:
4486 round up to a multiple of the alignment for arguments. */
4487 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4488 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4489 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4490 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4492 /* This isn't already where we want it on the stack, so put it there.
4493 This can either be done with push or copy insns. */
4494 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
,
4495 PARM_BOUNDARY
, partial
, reg
, used
- size
, argblock
,
4496 ARGS_SIZE_RTX (arg
->offset
), reg_parm_stack_space
,
4497 ARGS_SIZE_RTX (arg
->alignment_pad
));
4499 /* Unless this is a partially-in-register argument, the argument is now
4502 arg
->value
= arg
->stack
;
4506 /* BLKmode, at least partly to be pushed. */
4508 unsigned int parm_align
;
4512 /* Pushing a nonscalar.
4513 If part is passed in registers, PARTIAL says how much
4514 and emit_push_insn will take care of putting it there. */
4516 /* Round its size up to a multiple
4517 of the allocation unit for arguments. */
4519 if (arg
->size
.var
!= 0)
4522 size_rtx
= ARGS_SIZE_RTX (arg
->size
);
4526 /* PUSH_ROUNDING has no effect on us, because
4527 emit_push_insn for BLKmode is careful to avoid it. */
4528 excess
= (arg
->size
.constant
- int_size_in_bytes (TREE_TYPE (pval
))
4529 + partial
* UNITS_PER_WORD
);
4530 size_rtx
= expand_expr (size_in_bytes (TREE_TYPE (pval
)),
4531 NULL_RTX
, TYPE_MODE (sizetype
), 0);
4534 /* Some types will require stricter alignment, which will be
4535 provided for elsewhere in argument layout. */
4536 parm_align
= MAX (PARM_BOUNDARY
, TYPE_ALIGN (TREE_TYPE (pval
)));
4538 /* When an argument is padded down, the block is aligned to
4539 PARM_BOUNDARY, but the actual argument isn't. */
4540 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4543 parm_align
= BITS_PER_UNIT
;
4546 int excess_align
= (excess
& -excess
) * BITS_PER_UNIT
;
4547 parm_align
= MIN (parm_align
, excess_align
);
4551 if ((flags
& ECF_SIBCALL
) && GET_CODE (arg
->value
) == MEM
)
4553 /* emit_push_insn might not work properly if arg->value and
4554 argblock + arg->offset areas overlap. */
4558 if (XEXP (x
, 0) == current_function_internal_arg_pointer
4559 || (GET_CODE (XEXP (x
, 0)) == PLUS
4560 && XEXP (XEXP (x
, 0), 0) ==
4561 current_function_internal_arg_pointer
4562 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
))
4564 if (XEXP (x
, 0) != current_function_internal_arg_pointer
)
4565 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4567 /* expand_call should ensure this */
4568 if (arg
->offset
.var
|| GET_CODE (size_rtx
) != CONST_INT
)
4571 if (arg
->offset
.constant
> i
)
4573 if (arg
->offset
.constant
< i
+ INTVAL (size_rtx
))
4574 sibcall_failure
= 1;
4576 else if (arg
->offset
.constant
< i
)
4578 if (i
< arg
->offset
.constant
+ INTVAL (size_rtx
))
4579 sibcall_failure
= 1;
4584 /* Special handling is required if part of the parameter lies in the
4585 register parameter area. The argument may be copied into the stack
4586 slot using memcpy(), but the original contents of the register
4587 parameter area will be restored after the memcpy() call.
4589 To ensure that the part that lies in the register parameter area
4590 is copied correctly, we emit a separate push for that part. This
4591 push should be small enough to avoid a call to memcpy(). */
4592 #ifndef STACK_PARMS_IN_REG_PARM_AREA
4593 if (arg
->reg
&& arg
->pass_on_stack
)
4598 if (arg
->offset
.constant
< reg_parm_stack_space
&& arg
->offset
.var
)
4599 error ("variable offset is passed partially in stack and in reg");
4600 else if (arg
->offset
.constant
< reg_parm_stack_space
&& arg
->size
.var
)
4601 error ("variable size is passed partially in stack and in reg");
4602 else if (arg
->offset
.constant
< reg_parm_stack_space
4603 && ((arg
->offset
.constant
+ arg
->size
.constant
)
4604 > reg_parm_stack_space
))
4606 rtx size_rtx1
= GEN_INT (reg_parm_stack_space
- arg
->offset
.constant
);
4607 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx1
,
4608 parm_align
, partial
, reg
, excess
, argblock
,
4609 ARGS_SIZE_RTX (arg
->offset
), reg_parm_stack_space
,
4610 ARGS_SIZE_RTX (arg
->alignment_pad
));
4615 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4616 parm_align
, partial
, reg
, excess
, argblock
,
4617 ARGS_SIZE_RTX (arg
->offset
), reg_parm_stack_space
,
4618 ARGS_SIZE_RTX (arg
->alignment_pad
));
4620 /* Unless this is a partially-in-register argument, the argument is now
4623 ??? Unlike the case above, in which we want the actual
4624 address of the data, so that we can load it directly into a
4625 register, here we want the address of the stack slot, so that
4626 it's properly aligned for word-by-word copying or something
4627 like that. It's not clear that this is always correct. */
4629 arg
->value
= arg
->stack_slot
;
4632 /* Once we have pushed something, pops can't safely
4633 be deferred during the rest of the arguments. */
4636 /* ANSI doesn't require a sequence point here,
4637 but PCC has one, so this will avoid some problems. */
4640 /* Free any temporary slots made in processing this argument. Show
4641 that we might have taken the address of something and pushed that
4643 preserve_temp_slots (NULL_RTX
);
4647 return sibcall_failure
;