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
37 #if !defined FUNCTION_OK_FOR_SIBCALL
38 #define FUNCTION_OK_FOR_SIBCALL(DECL) 1
41 /* Decide whether a function's arguments should be processed
42 from first to last or from last to first.
44 They should if the stack and args grow in opposite directions, but
45 only if we have push insns. */
49 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
50 #define PUSH_ARGS_REVERSED PUSH_ARGS
55 #ifndef PUSH_ARGS_REVERSED
56 #define PUSH_ARGS_REVERSED 0
59 #ifndef STACK_POINTER_OFFSET
60 #define STACK_POINTER_OFFSET 0
63 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
64 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
66 /* Data structure and subroutines used within expand_call. */
70 /* Tree node for this argument. */
72 /* Mode for value; TYPE_MODE unless promoted. */
73 enum machine_mode mode
;
74 /* Current RTL value for argument, or 0 if it isn't precomputed. */
76 /* Initially-compute RTL value for argument; only for const functions. */
78 /* Register to pass this argument in, 0 if passed on stack, or an
79 PARALLEL if the arg is to be copied into multiple non-contiguous
82 /* Register to pass this argument in when generating tail call sequence.
83 This is not the same register as for normal calls on machines with
86 /* If REG was promoted from the actual mode of the argument expression,
87 indicates whether the promotion is sign- or zero-extended. */
89 /* Number of registers to use. 0 means put the whole arg in registers.
90 Also 0 if not passed in registers. */
92 /* Non-zero if argument must be passed on stack.
93 Note that some arguments may be passed on the stack
94 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
95 pass_on_stack identifies arguments that *cannot* go in registers. */
97 /* Offset of this argument from beginning of stack-args. */
98 struct args_size offset
;
99 /* Similar, but offset to the start of the stack slot. Different from
100 OFFSET if this arg pads downward. */
101 struct args_size slot_offset
;
102 /* Size of this argument on the stack, rounded up for any padding it gets,
103 parts of the argument passed in registers do not count.
104 If REG_PARM_STACK_SPACE is defined, then register parms
105 are counted here as well. */
106 struct args_size size
;
107 /* Location on the stack at which parameter should be stored. The store
108 has already been done if STACK == VALUE. */
110 /* Location on the stack of the start of this argument slot. This can
111 differ from STACK if this arg pads downward. This location is known
112 to be aligned to FUNCTION_ARG_BOUNDARY. */
114 /* Place that this stack area has been saved, if needed. */
116 /* If an argument's alignment does not permit direct copying into registers,
117 copy in smaller-sized pieces into pseudos. These are stored in a
118 block pointed to by this field. The next field says how many
119 word-sized pseudos we made. */
122 /* The amount that the stack pointer needs to be adjusted to
123 force alignment for the next argument. */
124 struct args_size alignment_pad
;
127 /* A vector of one char per byte of stack space. A byte if non-zero if
128 the corresponding stack location has been used.
129 This vector is used to prevent a function call within an argument from
130 clobbering any stack already set up. */
131 static char *stack_usage_map
;
133 /* Size of STACK_USAGE_MAP. */
134 static int highest_outgoing_arg_in_use
;
136 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
137 stack location's tail call argument has been already stored into the stack.
138 This bitmap is used to prevent sibling call optimization if function tries
139 to use parent's incoming argument slots when they have been already
140 overwritten with tail call arguments. */
141 static sbitmap stored_args_map
;
143 /* stack_arg_under_construction is nonzero when an argument may be
144 initialized with a constructor call (including a C function that
145 returns a BLKmode struct) and expand_call must take special action
146 to make sure the object being constructed does not overlap the
147 argument list for the constructor call. */
148 int stack_arg_under_construction
;
150 static int calls_function
PARAMS ((tree
, int));
151 static int calls_function_1
PARAMS ((tree
, int));
153 /* Nonzero if this is a call to a `const' function. */
155 /* Nonzero if this is a call to a `volatile' function. */
156 #define ECF_NORETURN 2
157 /* Nonzero if this is a call to malloc or a related function. */
159 /* Nonzero if it is plausible that this is a call to alloca. */
160 #define ECF_MAY_BE_ALLOCA 8
161 /* Nonzero if this is a call to a function that won't throw an exception. */
162 #define ECF_NOTHROW 16
163 /* Nonzero if this is a call to setjmp or a related function. */
164 #define ECF_RETURNS_TWICE 32
165 /* Nonzero if this is a call to `longjmp'. */
166 #define ECF_LONGJMP 64
167 /* Nonzero if this is a syscall that makes a new process in the image of
169 #define ECF_FORK_OR_EXEC 128
170 #define ECF_SIBCALL 256
171 /* Nonzero if this is a call to "pure" function (like const function,
172 but may read memory. */
174 /* Nonzero if this is a call to a function that returns with the stack
175 pointer depressed. */
176 #define ECF_SP_DEPRESSED 1024
177 /* Nonzero if this call is known to always return. */
178 #define ECF_ALWAYS_RETURN 2048
179 /* Create libcall block around the call. */
180 #define ECF_LIBCALL_BLOCK 4096
182 static void emit_call_1
PARAMS ((rtx
, tree
, tree
, HOST_WIDE_INT
,
183 HOST_WIDE_INT
, HOST_WIDE_INT
, rtx
,
184 rtx
, int, rtx
, int));
185 static void precompute_register_parameters
PARAMS ((int,
188 static int store_one_arg
PARAMS ((struct arg_data
*, rtx
, int, int,
190 static void store_unaligned_arguments_into_pseudos
PARAMS ((struct arg_data
*,
192 static int finalize_must_preallocate
PARAMS ((int, int,
194 struct args_size
*));
195 static void precompute_arguments
PARAMS ((int, int,
197 static int compute_argument_block_size
PARAMS ((int,
200 static void initialize_argument_information
PARAMS ((int,
207 static void compute_argument_addresses
PARAMS ((struct arg_data
*,
209 static rtx rtx_for_function_call
PARAMS ((tree
, tree
));
210 static void load_register_parameters
PARAMS ((struct arg_data
*,
212 static rtx emit_library_call_value_1
PARAMS ((int, rtx
, rtx
,
216 static int special_function_p
PARAMS ((tree
, int));
217 static int flags_from_decl_or_type
PARAMS ((tree
));
218 static rtx try_to_integrate
PARAMS ((tree
, tree
, rtx
,
220 static int check_sibcall_argument_overlap_1
PARAMS ((rtx
));
221 static int check_sibcall_argument_overlap
PARAMS ((rtx
, struct arg_data
*));
223 static int combine_pending_stack_adjustment_and_call
224 PARAMS ((int, struct args_size
*, int));
226 #ifdef REG_PARM_STACK_SPACE
227 static rtx save_fixed_argument_area
PARAMS ((int, rtx
, int *, int *));
228 static void restore_fixed_argument_area
PARAMS ((rtx
, rtx
, int, int));
231 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
234 If WHICH is 0, return 1 if EXP contains a call to any function.
235 Actually, we only need return 1 if evaluating EXP would require pushing
236 arguments on the stack, but that is too difficult to compute, so we just
237 assume any function call might require the stack. */
239 static tree calls_function_save_exprs
;
242 calls_function (exp
, which
)
248 calls_function_save_exprs
= 0;
249 val
= calls_function_1 (exp
, which
);
250 calls_function_save_exprs
= 0;
254 /* Recursive function to do the work of above function. */
257 calls_function_1 (exp
, which
)
262 enum tree_code code
= TREE_CODE (exp
);
263 int class = TREE_CODE_CLASS (code
);
264 int length
= first_rtl_op (code
);
266 /* If this code is language-specific, we don't know what it will do. */
267 if ((int) code
>= NUM_TREE_CODES
)
275 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp
, 0))))
277 && (TYPE_RETURNS_STACK_DEPRESSED
278 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp
, 0))))))
280 else if (TREE_CODE (TREE_OPERAND (exp
, 0)) == ADDR_EXPR
281 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0))
283 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0),
285 & ECF_MAY_BE_ALLOCA
))
294 for (tem
= CONSTRUCTOR_ELTS (exp
); tem
!= 0; tem
= TREE_CHAIN (tem
))
295 if (calls_function_1 (TREE_VALUE (tem
), which
))
302 if (SAVE_EXPR_RTL (exp
) != 0)
304 if (value_member (exp
, calls_function_save_exprs
))
306 calls_function_save_exprs
= tree_cons (NULL_TREE
, exp
,
307 calls_function_save_exprs
);
308 return (TREE_OPERAND (exp
, 0) != 0
309 && calls_function_1 (TREE_OPERAND (exp
, 0), which
));
316 for (local
= BLOCK_VARS (exp
); local
; local
= TREE_CHAIN (local
))
317 if (DECL_INITIAL (local
) != 0
318 && calls_function_1 (DECL_INITIAL (local
), which
))
321 for (subblock
= BLOCK_SUBBLOCKS (exp
);
323 subblock
= TREE_CHAIN (subblock
))
324 if (calls_function_1 (subblock
, which
))
330 for (; exp
!= 0; exp
= TREE_CHAIN (exp
))
331 if (calls_function_1 (TREE_VALUE (exp
), which
))
339 /* Only expressions, references, and blocks can contain calls. */
340 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
343 for (i
= 0; i
< length
; i
++)
344 if (TREE_OPERAND (exp
, i
) != 0
345 && calls_function_1 (TREE_OPERAND (exp
, i
), which
))
351 /* Force FUNEXP into a form suitable for the address of a CALL,
352 and return that as an rtx. Also load the static chain register
353 if FNDECL is a nested function.
355 CALL_FUSAGE points to a variable holding the prospective
356 CALL_INSN_FUNCTION_USAGE information. */
359 prepare_call_address (funexp
, fndecl
, call_fusage
, reg_parm_seen
, sibcallp
)
366 rtx static_chain_value
= 0;
368 funexp
= protect_from_queue (funexp
, 0);
371 /* Get possible static chain value for nested function in C. */
372 static_chain_value
= lookup_static_chain (fndecl
);
374 /* Make a valid memory address and copy constants thru pseudo-regs,
375 but not for a constant address if -fno-function-cse. */
376 if (GET_CODE (funexp
) != SYMBOL_REF
)
377 /* If we are using registers for parameters, force the
378 function address into a register now. */
379 funexp
= ((SMALL_REGISTER_CLASSES
&& reg_parm_seen
)
380 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
381 : memory_address (FUNCTION_MODE
, funexp
));
384 #ifndef NO_FUNCTION_CSE
385 if (optimize
&& ! flag_no_function_cse
)
386 #ifdef NO_RECURSIVE_FUNCTION_CSE
387 if (fndecl
!= current_function_decl
)
389 funexp
= force_reg (Pmode
, funexp
);
393 if (static_chain_value
!= 0)
395 emit_move_insn (static_chain_rtx
, static_chain_value
);
397 if (GET_CODE (static_chain_rtx
) == REG
)
398 use_reg (call_fusage
, static_chain_rtx
);
404 /* Generate instructions to call function FUNEXP,
405 and optionally pop the results.
406 The CALL_INSN is the first insn generated.
408 FNDECL is the declaration node of the function. This is given to the
409 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
411 FUNTYPE is the data type of the function. This is given to the macro
412 RETURN_POPS_ARGS to determine whether this function pops its own args.
413 We used to allow an identifier for library functions, but that doesn't
414 work when the return type is an aggregate type and the calling convention
415 says that the pointer to this aggregate is to be popped by the callee.
417 STACK_SIZE is the number of bytes of arguments on the stack,
418 ROUNDED_STACK_SIZE is that number rounded up to
419 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
420 both to put into the call insn and to generate explicit popping
423 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
424 It is zero if this call doesn't want a structure value.
426 NEXT_ARG_REG is the rtx that results from executing
427 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
428 just after all the args have had their registers assigned.
429 This could be whatever you like, but normally it is the first
430 arg-register beyond those used for args in this call,
431 or 0 if all the arg-registers are used in this call.
432 It is passed on to `gen_call' so you can put this info in the call insn.
434 VALREG is a hard register in which a value is returned,
435 or 0 if the call does not return a value.
437 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
438 the args to this call were processed.
439 We restore `inhibit_defer_pop' to that value.
441 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
442 denote registers used by the called function. */
445 emit_call_1 (funexp
, fndecl
, funtype
, stack_size
, rounded_stack_size
,
446 struct_value_size
, next_arg_reg
, valreg
, old_inhibit_defer_pop
,
447 call_fusage
, ecf_flags
)
449 tree fndecl ATTRIBUTE_UNUSED
;
450 tree funtype ATTRIBUTE_UNUSED
;
451 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED
;
452 HOST_WIDE_INT rounded_stack_size
;
453 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED
;
454 rtx next_arg_reg ATTRIBUTE_UNUSED
;
456 int old_inhibit_defer_pop
;
460 rtx rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
462 int already_popped
= 0;
463 HOST_WIDE_INT n_popped
= RETURN_POPS_ARGS (fndecl
, funtype
, stack_size
);
464 #if defined (HAVE_call) && defined (HAVE_call_value)
465 rtx struct_value_size_rtx
;
466 struct_value_size_rtx
= GEN_INT (struct_value_size
);
469 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
470 and we don't want to load it into a register as an optimization,
471 because prepare_call_address already did it if it should be done. */
472 if (GET_CODE (funexp
) != SYMBOL_REF
)
473 funexp
= memory_address (FUNCTION_MODE
, funexp
);
475 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
476 if ((ecf_flags
& ECF_SIBCALL
)
477 && HAVE_sibcall_pop
&& HAVE_sibcall_value_pop
478 && (n_popped
> 0 || stack_size
== 0))
480 rtx n_pop
= GEN_INT (n_popped
);
483 /* If this subroutine pops its own args, record that in the call insn
484 if possible, for the sake of frame pointer elimination. */
487 pat
= GEN_SIBCALL_VALUE_POP (valreg
,
488 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
489 rounded_stack_size_rtx
, next_arg_reg
,
492 pat
= GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
493 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
495 emit_call_insn (pat
);
501 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
502 /* If the target has "call" or "call_value" insns, then prefer them
503 if no arguments are actually popped. If the target does not have
504 "call" or "call_value" insns, then we must use the popping versions
505 even if the call has no arguments to pop. */
506 #if defined (HAVE_call) && defined (HAVE_call_value)
507 if (HAVE_call
&& HAVE_call_value
&& HAVE_call_pop
&& HAVE_call_value_pop
508 && n_popped
> 0 && ! (ecf_flags
& ECF_SP_DEPRESSED
))
510 if (HAVE_call_pop
&& HAVE_call_value_pop
)
513 rtx n_pop
= GEN_INT (n_popped
);
516 /* If this subroutine pops its own args, record that in the call insn
517 if possible, for the sake of frame pointer elimination. */
520 pat
= GEN_CALL_VALUE_POP (valreg
,
521 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
522 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
524 pat
= GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
525 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
527 emit_call_insn (pat
);
533 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
534 if ((ecf_flags
& ECF_SIBCALL
)
535 && HAVE_sibcall
&& HAVE_sibcall_value
)
538 emit_call_insn (GEN_SIBCALL_VALUE (valreg
,
539 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
540 rounded_stack_size_rtx
,
541 next_arg_reg
, NULL_RTX
));
543 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
544 rounded_stack_size_rtx
, next_arg_reg
,
545 struct_value_size_rtx
));
550 #if defined (HAVE_call) && defined (HAVE_call_value)
551 if (HAVE_call
&& HAVE_call_value
)
554 emit_call_insn (GEN_CALL_VALUE (valreg
,
555 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
556 rounded_stack_size_rtx
, next_arg_reg
,
559 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
560 rounded_stack_size_rtx
, next_arg_reg
,
561 struct_value_size_rtx
));
567 /* Find the CALL insn we just emitted. */
568 for (call_insn
= get_last_insn ();
569 call_insn
&& GET_CODE (call_insn
) != CALL_INSN
;
570 call_insn
= PREV_INSN (call_insn
))
576 /* Mark memory as used for "pure" function call. */
577 if (ecf_flags
& ECF_PURE
)
581 gen_rtx_USE (VOIDmode
,
582 gen_rtx_MEM (BLKmode
, gen_rtx_SCRATCH (VOIDmode
))),
585 /* Put the register usage information on the CALL. If there is already
586 some usage information, put ours at the end. */
587 if (CALL_INSN_FUNCTION_USAGE (call_insn
))
591 for (link
= CALL_INSN_FUNCTION_USAGE (call_insn
); XEXP (link
, 1) != 0;
592 link
= XEXP (link
, 1))
595 XEXP (link
, 1) = call_fusage
;
598 CALL_INSN_FUNCTION_USAGE (call_insn
) = call_fusage
;
600 /* If this is a const call, then set the insn's unchanging bit. */
601 if (ecf_flags
& (ECF_CONST
| ECF_PURE
))
602 CONST_OR_PURE_CALL_P (call_insn
) = 1;
604 /* If this call can't throw, attach a REG_EH_REGION reg note to that
606 if (ecf_flags
& ECF_NOTHROW
)
607 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_EH_REGION
, const0_rtx
,
608 REG_NOTES (call_insn
));
610 if (ecf_flags
& ECF_NORETURN
)
611 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_NORETURN
, const0_rtx
,
612 REG_NOTES (call_insn
));
613 if (ecf_flags
& ECF_ALWAYS_RETURN
)
614 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN
, const0_rtx
,
615 REG_NOTES (call_insn
));
617 if (ecf_flags
& ECF_RETURNS_TWICE
)
619 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_SETJMP
, const0_rtx
,
620 REG_NOTES (call_insn
));
621 current_function_calls_setjmp
= 1;
624 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
626 /* Restore this now, so that we do defer pops for this call's args
627 if the context of the call as a whole permits. */
628 inhibit_defer_pop
= old_inhibit_defer_pop
;
633 CALL_INSN_FUNCTION_USAGE (call_insn
)
634 = gen_rtx_EXPR_LIST (VOIDmode
,
635 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
636 CALL_INSN_FUNCTION_USAGE (call_insn
));
637 rounded_stack_size
-= n_popped
;
638 rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
639 stack_pointer_delta
-= n_popped
;
642 if (!ACCUMULATE_OUTGOING_ARGS
)
644 /* If returning from the subroutine does not automatically pop the args,
645 we need an instruction to pop them sooner or later.
646 Perhaps do it now; perhaps just record how much space to pop later.
648 If returning from the subroutine does pop the args, indicate that the
649 stack pointer will be changed. */
651 if (rounded_stack_size
!= 0)
653 if (ecf_flags
& ECF_SP_DEPRESSED
)
654 /* Just pretend we did the pop. */
655 stack_pointer_delta
-= rounded_stack_size
;
656 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
657 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
658 pending_stack_adjust
+= rounded_stack_size
;
660 adjust_stack (rounded_stack_size_rtx
);
663 /* When we accumulate outgoing args, we must avoid any stack manipulations.
664 Restore the stack pointer to its original value now. Usually
665 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
666 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
667 popping variants of functions exist as well.
669 ??? We may optimize similar to defer_pop above, but it is
670 probably not worthwhile.
672 ??? It will be worthwhile to enable combine_stack_adjustments even for
675 anti_adjust_stack (GEN_INT (n_popped
));
678 /* Determine if the function identified by NAME and FNDECL is one with
679 special properties we wish to know about.
681 For example, if the function might return more than one time (setjmp), then
682 set RETURNS_TWICE to a nonzero value.
684 Similarly set LONGJMP for if the function is in the longjmp family.
686 Set MALLOC for any of the standard memory allocation functions which
687 allocate from the heap.
689 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
690 space from the stack such as alloca. */
693 special_function_p (fndecl
, flags
)
697 if (! (flags
& ECF_MALLOC
)
698 && fndecl
&& DECL_NAME (fndecl
)
699 && IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) <= 17
700 /* Exclude functions not at the file scope, or not `extern',
701 since they are not the magic functions we would otherwise
703 && DECL_CONTEXT (fndecl
) == NULL_TREE
&& TREE_PUBLIC (fndecl
))
705 const char *name
= IDENTIFIER_POINTER (DECL_NAME (fndecl
));
706 const char *tname
= name
;
708 /* We assume that alloca will always be called by name. It
709 makes no sense to pass it as a pointer-to-function to
710 anything that does not understand its behavior. */
711 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 6
713 && ! strcmp (name
, "alloca"))
714 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 16
716 && ! strcmp (name
, "__builtin_alloca"))))
717 flags
|= ECF_MAY_BE_ALLOCA
;
719 /* Disregard prefix _, __ or __x. */
722 if (name
[1] == '_' && name
[2] == 'x')
724 else if (name
[1] == '_')
733 && (! strcmp (tname
, "setjmp")
734 || ! strcmp (tname
, "setjmp_syscall")))
736 && ! strcmp (tname
, "sigsetjmp"))
738 && ! strcmp (tname
, "savectx")))
739 flags
|= ECF_RETURNS_TWICE
;
742 && ! strcmp (tname
, "siglongjmp"))
743 flags
|= ECF_LONGJMP
;
745 else if ((tname
[0] == 'q' && tname
[1] == 's'
746 && ! strcmp (tname
, "qsetjmp"))
747 || (tname
[0] == 'v' && tname
[1] == 'f'
748 && ! strcmp (tname
, "vfork")))
749 flags
|= ECF_RETURNS_TWICE
;
751 else if (tname
[0] == 'l' && tname
[1] == 'o'
752 && ! strcmp (tname
, "longjmp"))
753 flags
|= ECF_LONGJMP
;
755 else if ((tname
[0] == 'f' && tname
[1] == 'o'
756 && ! strcmp (tname
, "fork"))
757 /* Linux specific: __clone. check NAME to insist on the
758 leading underscores, to avoid polluting the ISO / POSIX
760 || (name
[0] == '_' && name
[1] == '_'
761 && ! strcmp (tname
, "clone"))
762 || (tname
[0] == 'e' && tname
[1] == 'x' && tname
[2] == 'e'
763 && tname
[3] == 'c' && (tname
[4] == 'l' || tname
[4] == 'v')
765 || ((tname
[5] == 'p' || tname
[5] == 'e')
766 && tname
[6] == '\0'))))
767 flags
|= ECF_FORK_OR_EXEC
;
769 /* Do not add any more malloc-like functions to this list,
770 instead mark them as malloc functions using the malloc attribute.
771 Note, realloc is not suitable for attribute malloc since
772 it may return the same address across multiple calls.
773 C++ operator new is not suitable because it is not required
774 to return a unique pointer; indeed, the standard placement new
775 just returns its argument. */
776 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl
))) == Pmode
777 && (! strcmp (tname
, "malloc")
778 || ! strcmp (tname
, "calloc")
779 || ! strcmp (tname
, "strdup")))
785 /* Return nonzero when tree represent call to longjmp. */
788 setjmp_call_p (fndecl
)
791 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
794 /* Detect flags (function attributes) from the function decl or type node. */
797 flags_from_decl_or_type (exp
)
802 /* ??? We can't set IS_MALLOC for function types? */
805 type
= TREE_TYPE (exp
);
807 /* The function exp may have the `malloc' attribute. */
808 if (DECL_P (exp
) && DECL_IS_MALLOC (exp
))
811 /* The function exp may have the `pure' attribute. */
812 if (DECL_P (exp
) && DECL_IS_PURE (exp
))
813 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
815 if (TREE_NOTHROW (exp
))
816 flags
|= ECF_NOTHROW
;
819 if (TREE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
820 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
822 if (TREE_THIS_VOLATILE (exp
))
823 flags
|= ECF_NORETURN
;
825 /* Mark if the function returns with the stack pointer depressed. We
826 cannot consider it pure or constant in that case. */
827 if (TREE_CODE (type
) == FUNCTION_TYPE
&& TYPE_RETURNS_STACK_DEPRESSED (type
))
829 flags
|= ECF_SP_DEPRESSED
;
830 flags
&= ~(ECF_PURE
| ECF_CONST
| ECF_LIBCALL_BLOCK
);
836 /* Precompute all register parameters as described by ARGS, storing values
837 into fields within the ARGS array.
839 NUM_ACTUALS indicates the total number elements in the ARGS array.
841 Set REG_PARM_SEEN if we encounter a register parameter. */
844 precompute_register_parameters (num_actuals
, args
, reg_parm_seen
)
846 struct arg_data
*args
;
853 for (i
= 0; i
< num_actuals
; i
++)
854 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
858 if (args
[i
].value
== 0)
861 args
[i
].value
= expand_expr (args
[i
].tree_value
, NULL_RTX
,
863 preserve_temp_slots (args
[i
].value
);
866 /* ANSI doesn't require a sequence point here,
867 but PCC has one, so this will avoid some problems. */
871 /* If we are to promote the function arg to a wider mode,
874 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
876 = convert_modes (args
[i
].mode
,
877 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
878 args
[i
].value
, args
[i
].unsignedp
);
880 /* If the value is expensive, and we are inside an appropriately
881 short loop, put the value into a pseudo and then put the pseudo
884 For small register classes, also do this if this call uses
885 register parameters. This is to avoid reload conflicts while
886 loading the parameters registers. */
888 if ((! (GET_CODE (args
[i
].value
) == REG
889 || (GET_CODE (args
[i
].value
) == SUBREG
890 && GET_CODE (SUBREG_REG (args
[i
].value
)) == REG
)))
891 && args
[i
].mode
!= BLKmode
892 && rtx_cost (args
[i
].value
, SET
) > COSTS_N_INSNS (1)
893 && ((SMALL_REGISTER_CLASSES
&& *reg_parm_seen
)
894 || preserve_subexpressions_p ()))
895 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
899 #ifdef REG_PARM_STACK_SPACE
901 /* The argument list is the property of the called routine and it
902 may clobber it. If the fixed area has been used for previous
903 parameters, we must save and restore it. */
906 save_fixed_argument_area (reg_parm_stack_space
, argblock
,
907 low_to_save
, high_to_save
)
908 int reg_parm_stack_space
;
914 rtx save_area
= NULL_RTX
;
916 /* Compute the boundary of the that needs to be saved, if any. */
917 #ifdef ARGS_GROW_DOWNWARD
918 for (i
= 0; i
< reg_parm_stack_space
+ 1; i
++)
920 for (i
= 0; i
< reg_parm_stack_space
; i
++)
923 if (i
>= highest_outgoing_arg_in_use
924 || stack_usage_map
[i
] == 0)
927 if (*low_to_save
== -1)
933 if (*low_to_save
>= 0)
935 int num_to_save
= *high_to_save
- *low_to_save
+ 1;
936 enum machine_mode save_mode
937 = mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
940 /* If we don't have the required alignment, must do this in BLKmode. */
941 if ((*low_to_save
& (MIN (GET_MODE_SIZE (save_mode
),
942 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
945 #ifdef ARGS_GROW_DOWNWARD
947 = gen_rtx_MEM (save_mode
,
948 memory_address (save_mode
,
949 plus_constant (argblock
,
952 stack_area
= gen_rtx_MEM (save_mode
,
953 memory_address (save_mode
,
954 plus_constant (argblock
,
958 set_mem_align (stack_area
, PARM_BOUNDARY
);
959 if (save_mode
== BLKmode
)
961 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
962 /* Cannot use emit_block_move here because it can be done by a
963 library call which in turn gets into this place again and deadly
964 infinite recursion happens. */
965 move_by_pieces (validize_mem (save_area
), stack_area
, num_to_save
,
970 save_area
= gen_reg_rtx (save_mode
);
971 emit_move_insn (save_area
, stack_area
);
979 restore_fixed_argument_area (save_area
, argblock
, high_to_save
, low_to_save
)
985 enum machine_mode save_mode
= GET_MODE (save_area
);
986 #ifdef ARGS_GROW_DOWNWARD
988 = gen_rtx_MEM (save_mode
,
989 memory_address (save_mode
,
990 plus_constant (argblock
,
994 = gen_rtx_MEM (save_mode
,
995 memory_address (save_mode
,
996 plus_constant (argblock
,
1000 if (save_mode
!= BLKmode
)
1001 emit_move_insn (stack_area
, save_area
);
1003 /* Cannot use emit_block_move here because it can be done by a library
1004 call which in turn gets into this place again and deadly infinite
1005 recursion happens. */
1006 move_by_pieces (stack_area
, validize_mem (save_area
),
1007 high_to_save
- low_to_save
+ 1, PARM_BOUNDARY
);
1009 #endif /* REG_PARM_STACK_SPACE */
1011 /* If any elements in ARGS refer to parameters that are to be passed in
1012 registers, but not in memory, and whose alignment does not permit a
1013 direct copy into registers. Copy the values into a group of pseudos
1014 which we will later copy into the appropriate hard registers.
1016 Pseudos for each unaligned argument will be stored into the array
1017 args[argnum].aligned_regs. The caller is responsible for deallocating
1018 the aligned_regs array if it is nonzero. */
1021 store_unaligned_arguments_into_pseudos (args
, num_actuals
)
1022 struct arg_data
*args
;
1027 for (i
= 0; i
< num_actuals
; i
++)
1028 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
1029 && args
[i
].mode
== BLKmode
1030 && (TYPE_ALIGN (TREE_TYPE (args
[i
].tree_value
))
1031 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
1033 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1034 int big_endian_correction
= 0;
1036 args
[i
].n_aligned_regs
1037 = args
[i
].partial
? args
[i
].partial
1038 : (bytes
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1040 args
[i
].aligned_regs
= (rtx
*) xmalloc (sizeof (rtx
)
1041 * args
[i
].n_aligned_regs
);
1043 /* Structures smaller than a word are aligned to the least
1044 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1045 this means we must skip the empty high order bytes when
1046 calculating the bit offset. */
1047 if (BYTES_BIG_ENDIAN
1048 && !FUNCTION_ARG_REG_LITTLE_ENDIAN
1049 && bytes
< UNITS_PER_WORD
)
1050 big_endian_correction
= (BITS_PER_WORD
- (bytes
* BITS_PER_UNIT
));
1052 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1054 rtx reg
= gen_reg_rtx (word_mode
);
1055 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
1056 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
1058 args
[i
].aligned_regs
[j
] = reg
;
1060 /* There is no need to restrict this code to loading items
1061 in TYPE_ALIGN sized hunks. The bitfield instructions can
1062 load up entire word sized registers efficiently.
1064 ??? This may not be needed anymore.
1065 We use to emit a clobber here but that doesn't let later
1066 passes optimize the instructions we emit. By storing 0 into
1067 the register later passes know the first AND to zero out the
1068 bitfield being set in the register is unnecessary. The store
1069 of 0 will be deleted as will at least the first AND. */
1071 emit_move_insn (reg
, const0_rtx
);
1073 bytes
-= bitsize
/ BITS_PER_UNIT
;
1074 store_bit_field (reg
, bitsize
, big_endian_correction
, word_mode
,
1075 extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
1076 word_mode
, word_mode
,
1083 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1086 NUM_ACTUALS is the total number of parameters.
1088 N_NAMED_ARGS is the total number of named arguments.
1090 FNDECL is the tree code for the target of this call (if known)
1092 ARGS_SO_FAR holds state needed by the target to know where to place
1095 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1096 for arguments which are passed in registers.
1098 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1099 and may be modified by this routine.
1101 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1102 flags which may may be modified by this routine. */
1105 initialize_argument_information (num_actuals
, args
, args_size
, n_named_args
,
1106 actparms
, fndecl
, args_so_far
,
1107 reg_parm_stack_space
, old_stack_level
,
1108 old_pending_adj
, must_preallocate
,
1110 int num_actuals ATTRIBUTE_UNUSED
;
1111 struct arg_data
*args
;
1112 struct args_size
*args_size
;
1113 int n_named_args ATTRIBUTE_UNUSED
;
1116 CUMULATIVE_ARGS
*args_so_far
;
1117 int reg_parm_stack_space
;
1118 rtx
*old_stack_level
;
1119 int *old_pending_adj
;
1120 int *must_preallocate
;
1123 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1126 /* Count arg position in order args appear. */
1129 struct args_size alignment_pad
;
1133 args_size
->constant
= 0;
1136 /* In this loop, we consider args in the order they are written.
1137 We fill up ARGS from the front or from the back if necessary
1138 so that in any case the first arg to be pushed ends up at the front. */
1140 if (PUSH_ARGS_REVERSED
)
1142 i
= num_actuals
- 1, inc
= -1;
1143 /* In this case, must reverse order of args
1144 so that we compute and push the last arg first. */
1151 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1152 for (p
= actparms
, argpos
= 0; p
; p
= TREE_CHAIN (p
), i
+= inc
, argpos
++)
1154 tree type
= TREE_TYPE (TREE_VALUE (p
));
1156 enum machine_mode mode
;
1158 args
[i
].tree_value
= TREE_VALUE (p
);
1160 /* Replace erroneous argument with constant zero. */
1161 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1162 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1164 /* If TYPE is a transparent union, pass things the way we would
1165 pass the first field of the union. We have already verified that
1166 the modes are the same. */
1167 if (TREE_CODE (type
) == UNION_TYPE
&& TYPE_TRANSPARENT_UNION (type
))
1168 type
= TREE_TYPE (TYPE_FIELDS (type
));
1170 /* Decide where to pass this arg.
1172 args[i].reg is nonzero if all or part is passed in registers.
1174 args[i].partial is nonzero if part but not all is passed in registers,
1175 and the exact value says how many words are passed in registers.
1177 args[i].pass_on_stack is nonzero if the argument must at least be
1178 computed on the stack. It may then be loaded back into registers
1179 if args[i].reg is nonzero.
1181 These decisions are driven by the FUNCTION_... macros and must agree
1182 with those made by function.c. */
1184 /* See if this argument should be passed by invisible reference. */
1185 if ((TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1186 && contains_placeholder_p (TYPE_SIZE (type
)))
1187 || TREE_ADDRESSABLE (type
)
1188 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1189 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far
, TYPE_MODE (type
),
1190 type
, argpos
< n_named_args
)
1194 /* If we're compiling a thunk, pass through invisible
1195 references instead of making a copy. */
1196 if (current_function_is_thunk
1197 #ifdef FUNCTION_ARG_CALLEE_COPIES
1198 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far
, TYPE_MODE (type
),
1199 type
, argpos
< n_named_args
)
1200 /* If it's in a register, we must make a copy of it too. */
1201 /* ??? Is this a sufficient test? Is there a better one? */
1202 && !(TREE_CODE (args
[i
].tree_value
) == VAR_DECL
1203 && REG_P (DECL_RTL (args
[i
].tree_value
)))
1204 && ! TREE_ADDRESSABLE (type
))
1208 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1209 new object from the argument. If we are passing by
1210 invisible reference, the callee will do that for us, so we
1211 can strip off the TARGET_EXPR. This is not always safe,
1212 but it is safe in the only case where this is a useful
1213 optimization; namely, when the argument is a plain object.
1214 In that case, the frontend is just asking the backend to
1215 make a bitwise copy of the argument. */
1217 if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1218 && (DECL_P (TREE_OPERAND (args
[i
].tree_value
, 1)))
1219 && ! REG_P (DECL_RTL (TREE_OPERAND (args
[i
].tree_value
, 1))))
1220 args
[i
].tree_value
= TREE_OPERAND (args
[i
].tree_value
, 1);
1222 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1223 build_pointer_type (type
),
1224 args
[i
].tree_value
);
1225 type
= build_pointer_type (type
);
1227 else if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
)
1229 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1230 We implement this by passing the address of the temporary
1231 rather than expanding it into another allocated slot. */
1232 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1233 build_pointer_type (type
),
1234 args
[i
].tree_value
);
1235 type
= build_pointer_type (type
);
1239 /* We make a copy of the object and pass the address to the
1240 function being called. */
1243 if (!COMPLETE_TYPE_P (type
)
1244 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1245 || (flag_stack_check
&& ! STACK_CHECK_BUILTIN
1246 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type
),
1247 STACK_CHECK_MAX_VAR_SIZE
))))
1249 /* This is a variable-sized object. Make space on the stack
1251 rtx size_rtx
= expr_size (TREE_VALUE (p
));
1253 if (*old_stack_level
== 0)
1255 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1256 *old_pending_adj
= pending_stack_adjust
;
1257 pending_stack_adjust
= 0;
1260 copy
= gen_rtx_MEM (BLKmode
,
1261 allocate_dynamic_stack_space
1262 (size_rtx
, NULL_RTX
, TYPE_ALIGN (type
)));
1263 set_mem_attributes (copy
, type
, 1);
1266 copy
= assign_temp (type
, 0, 1, 0);
1268 store_expr (args
[i
].tree_value
, copy
, 0);
1269 *ecf_flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
1271 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1272 build_pointer_type (type
),
1273 make_tree (type
, copy
));
1274 type
= build_pointer_type (type
);
1278 mode
= TYPE_MODE (type
);
1279 unsignedp
= TREE_UNSIGNED (type
);
1281 #ifdef PROMOTE_FUNCTION_ARGS
1282 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
1285 args
[i
].unsignedp
= unsignedp
;
1286 args
[i
].mode
= mode
;
1288 args
[i
].reg
= FUNCTION_ARG (*args_so_far
, mode
, type
,
1289 argpos
< n_named_args
);
1290 #ifdef FUNCTION_INCOMING_ARG
1291 /* If this is a sibling call and the machine has register windows, the
1292 register window has to be unwinded before calling the routine, so
1293 arguments have to go into the incoming registers. */
1294 args
[i
].tail_call_reg
= FUNCTION_INCOMING_ARG (*args_so_far
, mode
, type
,
1295 argpos
< n_named_args
);
1297 args
[i
].tail_call_reg
= args
[i
].reg
;
1300 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1303 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far
, mode
, type
,
1304 argpos
< n_named_args
);
1307 args
[i
].pass_on_stack
= MUST_PASS_IN_STACK (mode
, type
);
1309 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1310 it means that we are to pass this arg in the register(s) designated
1311 by the PARALLEL, but also to pass it in the stack. */
1312 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1313 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1314 args
[i
].pass_on_stack
= 1;
1316 /* If this is an addressable type, we must preallocate the stack
1317 since we must evaluate the object into its final location.
1319 If this is to be passed in both registers and the stack, it is simpler
1321 if (TREE_ADDRESSABLE (type
)
1322 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1323 *must_preallocate
= 1;
1325 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1326 we cannot consider this function call constant. */
1327 if (TREE_ADDRESSABLE (type
))
1328 *ecf_flags
&= ~ECF_LIBCALL_BLOCK
;
1330 /* Compute the stack-size of this argument. */
1331 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1332 || reg_parm_stack_space
> 0
1333 || args
[i
].pass_on_stack
)
1334 locate_and_pad_parm (mode
, type
,
1335 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1340 fndecl
, args_size
, &args
[i
].offset
,
1341 &args
[i
].size
, &alignment_pad
);
1343 #ifndef ARGS_GROW_DOWNWARD
1344 args
[i
].slot_offset
= *args_size
;
1347 args
[i
].alignment_pad
= alignment_pad
;
1349 /* If a part of the arg was put into registers,
1350 don't include that part in the amount pushed. */
1351 if (reg_parm_stack_space
== 0 && ! args
[i
].pass_on_stack
)
1352 args
[i
].size
.constant
-= ((args
[i
].partial
* UNITS_PER_WORD
)
1353 / (PARM_BOUNDARY
/ BITS_PER_UNIT
)
1354 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
1356 /* Update ARGS_SIZE, the total stack space for args so far. */
1358 args_size
->constant
+= args
[i
].size
.constant
;
1359 if (args
[i
].size
.var
)
1361 ADD_PARM_SIZE (*args_size
, args
[i
].size
.var
);
1364 /* Since the slot offset points to the bottom of the slot,
1365 we must record it after incrementing if the args grow down. */
1366 #ifdef ARGS_GROW_DOWNWARD
1367 args
[i
].slot_offset
= *args_size
;
1369 args
[i
].slot_offset
.constant
= -args_size
->constant
;
1371 SUB_PARM_SIZE (args
[i
].slot_offset
, args_size
->var
);
1374 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1375 have been used, etc. */
1377 FUNCTION_ARG_ADVANCE (*args_so_far
, TYPE_MODE (type
), type
,
1378 argpos
< n_named_args
);
1382 /* Update ARGS_SIZE to contain the total size for the argument block.
1383 Return the original constant component of the argument block's size.
1385 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1386 for arguments passed in registers. */
1389 compute_argument_block_size (reg_parm_stack_space
, args_size
,
1390 preferred_stack_boundary
)
1391 int reg_parm_stack_space
;
1392 struct args_size
*args_size
;
1393 int preferred_stack_boundary ATTRIBUTE_UNUSED
;
1395 int unadjusted_args_size
= args_size
->constant
;
1397 /* For accumulate outgoing args mode we don't need to align, since the frame
1398 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1399 backends from generating misaligned frame sizes. */
1400 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1401 preferred_stack_boundary
= STACK_BOUNDARY
;
1403 /* Compute the actual size of the argument block required. The variable
1404 and constant sizes must be combined, the size may have to be rounded,
1405 and there may be a minimum required size. */
1409 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1410 args_size
->constant
= 0;
1412 preferred_stack_boundary
/= BITS_PER_UNIT
;
1413 if (preferred_stack_boundary
> 1)
1415 /* We don't handle this case yet. To handle it correctly we have
1416 to add the delta, round and subtract the delta.
1417 Currently no machine description requires this support. */
1418 if (stack_pointer_delta
& (preferred_stack_boundary
- 1))
1420 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1423 if (reg_parm_stack_space
> 0)
1426 = size_binop (MAX_EXPR
, args_size
->var
,
1427 ssize_int (reg_parm_stack_space
));
1429 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1430 /* The area corresponding to register parameters is not to count in
1431 the size of the block we need. So make the adjustment. */
1433 = size_binop (MINUS_EXPR
, args_size
->var
,
1434 ssize_int (reg_parm_stack_space
));
1440 preferred_stack_boundary
/= BITS_PER_UNIT
;
1441 if (preferred_stack_boundary
< 1)
1442 preferred_stack_boundary
= 1;
1443 args_size
->constant
= (((args_size
->constant
1444 + stack_pointer_delta
1445 + preferred_stack_boundary
- 1)
1446 / preferred_stack_boundary
1447 * preferred_stack_boundary
)
1448 - stack_pointer_delta
);
1450 args_size
->constant
= MAX (args_size
->constant
,
1451 reg_parm_stack_space
);
1453 #ifdef MAYBE_REG_PARM_STACK_SPACE
1454 if (reg_parm_stack_space
== 0)
1455 args_size
->constant
= 0;
1458 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1459 args_size
->constant
-= reg_parm_stack_space
;
1462 return unadjusted_args_size
;
1465 /* Precompute parameters as needed for a function call.
1467 FLAGS is mask of ECF_* constants.
1469 NUM_ACTUALS is the number of arguments.
1471 ARGS is an array containing information for each argument; this
1472 routine fills in the INITIAL_VALUE and VALUE fields for each
1473 precomputed argument. */
1476 precompute_arguments (flags
, num_actuals
, args
)
1479 struct arg_data
*args
;
1483 /* If this function call is cse'able, precompute all the parameters.
1484 Note that if the parameter is constructed into a temporary, this will
1485 cause an additional copy because the parameter will be constructed
1486 into a temporary location and then copied into the outgoing arguments.
1487 If a parameter contains a call to alloca and this function uses the
1488 stack, precompute the parameter. */
1490 /* If we preallocated the stack space, and some arguments must be passed
1491 on the stack, then we must precompute any parameter which contains a
1492 function call which will store arguments on the stack.
1493 Otherwise, evaluating the parameter may clobber previous parameters
1494 which have already been stored into the stack. (we have code to avoid
1495 such case by saving the outgoing stack arguments, but it results in
1498 for (i
= 0; i
< num_actuals
; i
++)
1499 if ((flags
& ECF_LIBCALL_BLOCK
)
1500 || calls_function (args
[i
].tree_value
, !ACCUMULATE_OUTGOING_ARGS
))
1502 enum machine_mode mode
;
1504 /* If this is an addressable type, we cannot pre-evaluate it. */
1505 if (TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
)))
1511 = expand_expr (args
[i
].tree_value
, NULL_RTX
, VOIDmode
, 0);
1513 preserve_temp_slots (args
[i
].value
);
1516 /* ANSI doesn't require a sequence point here,
1517 but PCC has one, so this will avoid some problems. */
1520 args
[i
].initial_value
= args
[i
].value
1521 = protect_from_queue (args
[i
].value
, 0);
1523 mode
= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
));
1524 if (mode
!= args
[i
].mode
)
1527 = convert_modes (args
[i
].mode
, mode
,
1528 args
[i
].value
, args
[i
].unsignedp
);
1529 #ifdef PROMOTE_FOR_CALL_ONLY
1530 /* CSE will replace this only if it contains args[i].value
1531 pseudo, so convert it down to the declared mode using
1533 if (GET_CODE (args
[i
].value
) == REG
1534 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
)
1536 args
[i
].initial_value
1537 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1538 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1539 SUBREG_PROMOTED_UNSIGNED_P (args
[i
].initial_value
)
1540 = args
[i
].unsignedp
;
1547 /* Given the current state of MUST_PREALLOCATE and information about
1548 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1549 compute and return the final value for MUST_PREALLOCATE. */
1552 finalize_must_preallocate (must_preallocate
, num_actuals
, args
, args_size
)
1553 int must_preallocate
;
1555 struct arg_data
*args
;
1556 struct args_size
*args_size
;
1558 /* See if we have or want to preallocate stack space.
1560 If we would have to push a partially-in-regs parm
1561 before other stack parms, preallocate stack space instead.
1563 If the size of some parm is not a multiple of the required stack
1564 alignment, we must preallocate.
1566 If the total size of arguments that would otherwise create a copy in
1567 a temporary (such as a CALL) is more than half the total argument list
1568 size, preallocation is faster.
1570 Another reason to preallocate is if we have a machine (like the m88k)
1571 where stack alignment is required to be maintained between every
1572 pair of insns, not just when the call is made. However, we assume here
1573 that such machines either do not have push insns (and hence preallocation
1574 would occur anyway) or the problem is taken care of with
1577 if (! must_preallocate
)
1579 int partial_seen
= 0;
1580 int copy_to_evaluate_size
= 0;
1583 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1585 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1587 else if (partial_seen
&& args
[i
].reg
== 0)
1588 must_preallocate
= 1;
1590 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1591 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1592 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1593 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1594 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1595 copy_to_evaluate_size
1596 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1599 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1600 && args_size
->constant
> 0)
1601 must_preallocate
= 1;
1603 return must_preallocate
;
1606 /* If we preallocated stack space, compute the address of each argument
1607 and store it into the ARGS array.
1609 We need not ensure it is a valid memory address here; it will be
1610 validized when it is used.
1612 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1615 compute_argument_addresses (args
, argblock
, num_actuals
)
1616 struct arg_data
*args
;
1622 rtx arg_reg
= argblock
;
1623 int i
, arg_offset
= 0;
1625 if (GET_CODE (argblock
) == PLUS
)
1626 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1628 for (i
= 0; i
< num_actuals
; i
++)
1630 rtx offset
= ARGS_SIZE_RTX (args
[i
].offset
);
1631 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].slot_offset
);
1634 /* Skip this parm if it will not be passed on the stack. */
1635 if (! args
[i
].pass_on_stack
&& args
[i
].reg
!= 0)
1638 if (GET_CODE (offset
) == CONST_INT
)
1639 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1641 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1643 addr
= plus_constant (addr
, arg_offset
);
1644 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1645 set_mem_attributes (args
[i
].stack
,
1646 TREE_TYPE (args
[i
].tree_value
), 1);
1648 if (GET_CODE (slot_offset
) == CONST_INT
)
1649 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1651 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1653 addr
= plus_constant (addr
, arg_offset
);
1654 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1655 set_mem_attributes (args
[i
].stack_slot
,
1656 TREE_TYPE (args
[i
].tree_value
), 1);
1658 /* Function incoming arguments may overlap with sibling call
1659 outgoing arguments and we cannot allow reordering of reads
1660 from function arguments with stores to outgoing arguments
1661 of sibling calls. */
1662 set_mem_alias_set (args
[i
].stack
, 0);
1663 set_mem_alias_set (args
[i
].stack_slot
, 0);
1668 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1669 in a call instruction.
1671 FNDECL is the tree node for the target function. For an indirect call
1672 FNDECL will be NULL_TREE.
1674 EXP is the CALL_EXPR for this call. */
1677 rtx_for_function_call (fndecl
, exp
)
1683 /* Get the function to call, in the form of RTL. */
1686 /* If this is the first use of the function, see if we need to
1687 make an external definition for it. */
1688 if (! TREE_USED (fndecl
))
1690 assemble_external (fndecl
);
1691 TREE_USED (fndecl
) = 1;
1694 /* Get a SYMBOL_REF rtx for the function address. */
1695 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1698 /* Generate an rtx (probably a pseudo-register) for the address. */
1703 = expand_expr (TREE_OPERAND (exp
, 0), NULL_RTX
, VOIDmode
, 0);
1704 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1710 /* Do the register loads required for any wholly-register parms or any
1711 parms which are passed both on the stack and in a register. Their
1712 expressions were already evaluated.
1714 Mark all register-parms as living through the call, putting these USE
1715 insns in the CALL_INSN_FUNCTION_USAGE field. */
1718 load_register_parameters (args
, num_actuals
, call_fusage
, flags
)
1719 struct arg_data
*args
;
1726 #ifdef LOAD_ARGS_REVERSED
1727 for (i
= num_actuals
- 1; i
>= 0; i
--)
1729 for (i
= 0; i
< num_actuals
; i
++)
1732 rtx reg
= ((flags
& ECF_SIBCALL
)
1733 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1734 int partial
= args
[i
].partial
;
1739 /* Set to non-negative if must move a word at a time, even if just
1740 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1741 we just use a normal move insn. This value can be zero if the
1742 argument is a zero size structure with no fields. */
1743 nregs
= (partial
? partial
1744 : (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1745 ? ((int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
))
1746 + (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
)
1749 /* Handle calls that pass values in multiple non-contiguous
1750 locations. The Irix 6 ABI has examples of this. */
1752 if (GET_CODE (reg
) == PARALLEL
)
1753 emit_group_load (reg
, args
[i
].value
,
1754 int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
)));
1756 /* If simple case, just do move. If normal partial, store_one_arg
1757 has already loaded the register for us. In all other cases,
1758 load the register(s) from memory. */
1760 else if (nregs
== -1)
1761 emit_move_insn (reg
, args
[i
].value
);
1763 /* If we have pre-computed the values to put in the registers in
1764 the case of non-aligned structures, copy them in now. */
1766 else if (args
[i
].n_aligned_regs
!= 0)
1767 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1768 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1769 args
[i
].aligned_regs
[j
]);
1771 else if (partial
== 0 || args
[i
].pass_on_stack
)
1772 move_block_to_reg (REGNO (reg
),
1773 validize_mem (args
[i
].value
), nregs
,
1776 /* Handle calls that pass values in multiple non-contiguous
1777 locations. The Irix 6 ABI has examples of this. */
1778 if (GET_CODE (reg
) == PARALLEL
)
1779 use_group_regs (call_fusage
, reg
);
1780 else if (nregs
== -1)
1781 use_reg (call_fusage
, reg
);
1783 use_regs (call_fusage
, REGNO (reg
), nregs
== 0 ? 1 : nregs
);
1788 /* Try to integrate function. See expand_inline_function for documentation
1789 about the parameters. */
1792 try_to_integrate (fndecl
, actparms
, target
, ignore
, type
, structure_value_addr
)
1798 rtx structure_value_addr
;
1803 rtx old_stack_level
= 0;
1804 int reg_parm_stack_space
= 0;
1806 #ifdef REG_PARM_STACK_SPACE
1807 #ifdef MAYBE_REG_PARM_STACK_SPACE
1808 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
1810 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
1814 before_call
= get_last_insn ();
1816 timevar_push (TV_INTEGRATION
);
1818 temp
= expand_inline_function (fndecl
, actparms
, target
,
1820 structure_value_addr
);
1822 timevar_pop (TV_INTEGRATION
);
1824 /* If inlining succeeded, return. */
1825 if (temp
!= (rtx
) (HOST_WIDE_INT
) - 1)
1827 if (ACCUMULATE_OUTGOING_ARGS
)
1829 /* If the outgoing argument list must be preserved, push
1830 the stack before executing the inlined function if it
1833 for (i
= reg_parm_stack_space
- 1; i
>= 0; i
--)
1834 if (i
< highest_outgoing_arg_in_use
&& stack_usage_map
[i
] != 0)
1837 if (stack_arg_under_construction
|| i
>= 0)
1840 = before_call
? NEXT_INSN (before_call
) : get_insns ();
1841 rtx insn
= NULL_RTX
, seq
;
1843 /* Look for a call in the inline function code.
1844 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1845 nonzero then there is a call and it is not necessary
1846 to scan the insns. */
1848 if (DECL_SAVED_INSNS (fndecl
)->outgoing_args_size
== 0)
1849 for (insn
= first_insn
; insn
; insn
= NEXT_INSN (insn
))
1850 if (GET_CODE (insn
) == CALL_INSN
)
1855 /* Reserve enough stack space so that the largest
1856 argument list of any function call in the inline
1857 function does not overlap the argument list being
1858 evaluated. This is usually an overestimate because
1859 allocate_dynamic_stack_space reserves space for an
1860 outgoing argument list in addition to the requested
1861 space, but there is no way to ask for stack space such
1862 that an argument list of a certain length can be
1865 Add the stack space reserved for register arguments, if
1866 any, in the inline function. What is really needed is the
1867 largest value of reg_parm_stack_space in the inline
1868 function, but that is not available. Using the current
1869 value of reg_parm_stack_space is wrong, but gives
1870 correct results on all supported machines. */
1872 int adjust
= (DECL_SAVED_INSNS (fndecl
)->outgoing_args_size
1873 + reg_parm_stack_space
);
1876 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
1877 allocate_dynamic_stack_space (GEN_INT (adjust
),
1878 NULL_RTX
, BITS_PER_UNIT
);
1881 emit_insns_before (seq
, first_insn
);
1882 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1887 /* If the result is equivalent to TARGET, return TARGET to simplify
1888 checks in store_expr. They can be equivalent but not equal in the
1889 case of a function that returns BLKmode. */
1890 if (temp
!= target
&& rtx_equal_p (temp
, target
))
1895 /* If inlining failed, mark FNDECL as needing to be compiled
1896 separately after all. If function was declared inline,
1898 if (DECL_INLINE (fndecl
) && warn_inline
&& !flag_no_inline
1899 && optimize
> 0 && !TREE_ADDRESSABLE (fndecl
))
1901 warning_with_decl (fndecl
, "inlining failed in call to `%s'");
1902 warning ("called from here");
1904 mark_addressable (fndecl
);
1905 return (rtx
) (HOST_WIDE_INT
) - 1;
1908 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1909 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1910 bytes, then we would need to push some additional bytes to pad the
1911 arguments. So, we compute an adjust to the stack pointer for an
1912 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1913 bytes. Then, when the arguments are pushed the stack will be perfectly
1914 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1915 be popped after the call. Returns the adjustment. */
1918 combine_pending_stack_adjustment_and_call (unadjusted_args_size
,
1920 preferred_unit_stack_boundary
)
1921 int unadjusted_args_size
;
1922 struct args_size
*args_size
;
1923 int preferred_unit_stack_boundary
;
1925 /* The number of bytes to pop so that the stack will be
1926 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1927 HOST_WIDE_INT adjustment
;
1928 /* The alignment of the stack after the arguments are pushed, if we
1929 just pushed the arguments without adjust the stack here. */
1930 HOST_WIDE_INT unadjusted_alignment
;
1932 unadjusted_alignment
1933 = ((stack_pointer_delta
+ unadjusted_args_size
)
1934 % preferred_unit_stack_boundary
);
1936 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1937 as possible -- leaving just enough left to cancel out the
1938 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1939 PENDING_STACK_ADJUST is non-negative, and congruent to
1940 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1942 /* Begin by trying to pop all the bytes. */
1943 unadjusted_alignment
1944 = (unadjusted_alignment
1945 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1946 adjustment
= pending_stack_adjust
;
1947 /* Push enough additional bytes that the stack will be aligned
1948 after the arguments are pushed. */
1949 if (preferred_unit_stack_boundary
> 1)
1951 if (unadjusted_alignment
> 0)
1952 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1954 adjustment
+= unadjusted_alignment
;
1957 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1958 bytes after the call. The right number is the entire
1959 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1960 by the arguments in the first place. */
1962 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1967 /* Scan X expression if it does not dereference any argument slots
1968 we already clobbered by tail call arguments (as noted in stored_args_map
1970 Return non-zero if X expression dereferences such argument slots,
1974 check_sibcall_argument_overlap_1 (x
)
1985 code
= GET_CODE (x
);
1989 if (XEXP (x
, 0) == current_function_internal_arg_pointer
)
1991 else if (GET_CODE (XEXP (x
, 0)) == PLUS
1992 && XEXP (XEXP (x
, 0), 0) ==
1993 current_function_internal_arg_pointer
1994 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
)
1995 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
1999 #ifdef ARGS_GROW_DOWNWARD
2000 i
= -i
- GET_MODE_SIZE (GET_MODE (x
));
2003 for (k
= 0; k
< GET_MODE_SIZE (GET_MODE (x
)); k
++)
2004 if (i
+ k
< stored_args_map
->n_bits
2005 && TEST_BIT (stored_args_map
, i
+ k
))
2011 /* Scan all subexpressions. */
2012 fmt
= GET_RTX_FORMAT (code
);
2013 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
2017 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
2020 else if (*fmt
== 'E')
2022 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2023 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
2030 /* Scan sequence after INSN if it does not dereference any argument slots
2031 we already clobbered by tail call arguments (as noted in stored_args_map
2032 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2033 Return non-zero if sequence after INSN dereferences such argument slots,
2037 check_sibcall_argument_overlap (insn
, arg
)
2039 struct arg_data
*arg
;
2043 if (insn
== NULL_RTX
)
2044 insn
= get_insns ();
2046 insn
= NEXT_INSN (insn
);
2048 for (; insn
; insn
= NEXT_INSN (insn
))
2050 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
2053 #ifdef ARGS_GROW_DOWNWARD
2054 low
= -arg
->slot_offset
.constant
- arg
->size
.constant
;
2056 low
= arg
->slot_offset
.constant
;
2059 for (high
= low
+ arg
->size
.constant
; low
< high
; low
++)
2060 SET_BIT (stored_args_map
, low
);
2061 return insn
!= NULL_RTX
;
2064 /* Generate all the code for a function call
2065 and return an rtx for its value.
2066 Store the value in TARGET (specified as an rtx) if convenient.
2067 If the value is stored in TARGET then TARGET is returned.
2068 If IGNORE is nonzero, then we ignore the value of the function call. */
2071 expand_call (exp
, target
, ignore
)
2076 /* Nonzero if we are currently expanding a call. */
2077 static int currently_expanding_call
= 0;
2079 /* List of actual parameters. */
2080 tree actparms
= TREE_OPERAND (exp
, 1);
2081 /* RTX for the function to be called. */
2083 /* Sequence of insns to perform a tail recursive "call". */
2084 rtx tail_recursion_insns
= NULL_RTX
;
2085 /* Sequence of insns to perform a normal "call". */
2086 rtx normal_call_insns
= NULL_RTX
;
2087 /* Sequence of insns to perform a tail recursive "call". */
2088 rtx tail_call_insns
= NULL_RTX
;
2089 /* Data type of the function. */
2091 /* Declaration of the function being called,
2092 or 0 if the function is computed (not known by name). */
2095 int try_tail_call
= 1;
2096 int try_tail_recursion
= 1;
2099 /* Register in which non-BLKmode value will be returned,
2100 or 0 if no value or if value is BLKmode. */
2102 /* Address where we should return a BLKmode value;
2103 0 if value not BLKmode. */
2104 rtx structure_value_addr
= 0;
2105 /* Nonzero if that address is being passed by treating it as
2106 an extra, implicit first parameter. Otherwise,
2107 it is passed by being copied directly into struct_value_rtx. */
2108 int structure_value_addr_parm
= 0;
2109 /* Size of aggregate value wanted, or zero if none wanted
2110 or if we are using the non-reentrant PCC calling convention
2111 or expecting the value in registers. */
2112 HOST_WIDE_INT struct_value_size
= 0;
2113 /* Nonzero if called function returns an aggregate in memory PCC style,
2114 by returning the address of where to find it. */
2115 int pcc_struct_value
= 0;
2117 /* Number of actual parameters in this call, including struct value addr. */
2119 /* Number of named args. Args after this are anonymous ones
2120 and they must all go on the stack. */
2123 /* Vector of information about each argument.
2124 Arguments are numbered in the order they will be pushed,
2125 not the order they are written. */
2126 struct arg_data
*args
;
2128 /* Total size in bytes of all the stack-parms scanned so far. */
2129 struct args_size args_size
;
2130 struct args_size adjusted_args_size
;
2131 /* Size of arguments before any adjustments (such as rounding). */
2132 int unadjusted_args_size
;
2133 /* Data on reg parms scanned so far. */
2134 CUMULATIVE_ARGS args_so_far
;
2135 /* Nonzero if a reg parm has been scanned. */
2137 /* Nonzero if this is an indirect function call. */
2139 /* Nonzero if we must avoid push-insns in the args for this call.
2140 If stack space is allocated for register parameters, but not by the
2141 caller, then it is preallocated in the fixed part of the stack frame.
2142 So the entire argument block must then be preallocated (i.e., we
2143 ignore PUSH_ROUNDING in that case). */
2145 int must_preallocate
= !PUSH_ARGS
;
2147 /* Size of the stack reserved for parameter registers. */
2148 int reg_parm_stack_space
= 0;
2150 /* Address of space preallocated for stack parms
2151 (on machines that lack push insns), or 0 if space not preallocated. */
2154 /* Mask of ECF_ flags. */
2156 /* Nonzero if this is a call to an inline function. */
2157 int is_integrable
= 0;
2158 #ifdef REG_PARM_STACK_SPACE
2159 /* Define the boundary of the register parm stack space that needs to be
2161 int low_to_save
= -1, high_to_save
;
2162 rtx save_area
= 0; /* Place that it is saved */
2165 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
2166 char *initial_stack_usage_map
= stack_usage_map
;
2167 int old_stack_arg_under_construction
= 0;
2169 rtx old_stack_level
= 0;
2170 int old_pending_adj
= 0;
2171 int old_inhibit_defer_pop
= inhibit_defer_pop
;
2172 int old_stack_allocated
;
2174 tree p
= TREE_OPERAND (exp
, 0);
2176 /* The alignment of the stack, in bits. */
2177 HOST_WIDE_INT preferred_stack_boundary
;
2178 /* The alignment of the stack, in bytes. */
2179 HOST_WIDE_INT preferred_unit_stack_boundary
;
2181 /* See if this is "nothrow" function call. */
2182 if (TREE_NOTHROW (exp
))
2183 flags
|= ECF_NOTHROW
;
2185 /* See if we can find a DECL-node for the actual function.
2186 As a result, decide whether this is a call to an integrable function. */
2188 fndecl
= get_callee_fndecl (exp
);
2192 && fndecl
!= current_function_decl
2193 && DECL_INLINE (fndecl
)
2194 && DECL_SAVED_INSNS (fndecl
)
2195 && DECL_SAVED_INSNS (fndecl
)->inlinable
)
2197 else if (! TREE_ADDRESSABLE (fndecl
))
2199 /* In case this function later becomes inlinable,
2200 record that there was already a non-inline call to it.
2202 Use abstraction instead of setting TREE_ADDRESSABLE
2204 if (DECL_INLINE (fndecl
) && warn_inline
&& !flag_no_inline
2207 warning_with_decl (fndecl
, "can't inline call to `%s'");
2208 warning ("called from here");
2210 mark_addressable (fndecl
);
2213 flags
|= flags_from_decl_or_type (fndecl
);
2216 /* If we don't have specific function to call, see if we have a
2217 attributes set in the type. */
2219 flags
|= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p
)));
2221 #ifdef REG_PARM_STACK_SPACE
2222 #ifdef MAYBE_REG_PARM_STACK_SPACE
2223 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
2225 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
2229 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2230 if (reg_parm_stack_space
> 0 && PUSH_ARGS
)
2231 must_preallocate
= 1;
2234 /* Warn if this value is an aggregate type,
2235 regardless of which calling convention we are using for it. */
2236 if (warn_aggregate_return
&& AGGREGATE_TYPE_P (TREE_TYPE (exp
)))
2237 warning ("function call has aggregate value");
2239 /* Set up a place to return a structure. */
2241 /* Cater to broken compilers. */
2242 if (aggregate_value_p (exp
))
2244 /* This call returns a big structure. */
2245 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
2247 #ifdef PCC_STATIC_STRUCT_RETURN
2249 pcc_struct_value
= 1;
2250 /* Easier than making that case work right. */
2253 /* In case this is a static function, note that it has been
2255 if (! TREE_ADDRESSABLE (fndecl
))
2256 mark_addressable (fndecl
);
2260 #else /* not PCC_STATIC_STRUCT_RETURN */
2262 struct_value_size
= int_size_in_bytes (TREE_TYPE (exp
));
2264 if (target
&& GET_CODE (target
) == MEM
)
2265 structure_value_addr
= XEXP (target
, 0);
2268 /* For variable-sized objects, we must be called with a target
2269 specified. If we were to allocate space on the stack here,
2270 we would have no way of knowing when to free it. */
2271 rtx d
= assign_temp (TREE_TYPE (exp
), 1, 1, 1);
2273 mark_temp_addr_taken (d
);
2274 structure_value_addr
= XEXP (d
, 0);
2278 #endif /* not PCC_STATIC_STRUCT_RETURN */
2281 /* If called function is inline, try to integrate it. */
2285 rtx temp
= try_to_integrate (fndecl
, actparms
, target
,
2286 ignore
, TREE_TYPE (exp
),
2287 structure_value_addr
);
2288 if (temp
!= (rtx
) (HOST_WIDE_INT
) - 1)
2292 /* Figure out the amount to which the stack should be aligned. */
2293 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2295 /* Operand 0 is a pointer-to-function; get the type of the function. */
2296 funtype
= TREE_TYPE (TREE_OPERAND (exp
, 0));
2297 if (! POINTER_TYPE_P (funtype
))
2299 funtype
= TREE_TYPE (funtype
);
2301 /* See if this is a call to a function that can return more than once
2302 or a call to longjmp or malloc. */
2303 flags
|= special_function_p (fndecl
, flags
);
2305 if (flags
& ECF_MAY_BE_ALLOCA
)
2306 current_function_calls_alloca
= 1;
2308 /* If struct_value_rtx is 0, it means pass the address
2309 as if it were an extra parameter. */
2310 if (structure_value_addr
&& struct_value_rtx
== 0)
2312 /* If structure_value_addr is a REG other than
2313 virtual_outgoing_args_rtx, we can use always use it. If it
2314 is not a REG, we must always copy it into a register.
2315 If it is virtual_outgoing_args_rtx, we must copy it to another
2316 register in some cases. */
2317 rtx temp
= (GET_CODE (structure_value_addr
) != REG
2318 || (ACCUMULATE_OUTGOING_ARGS
2319 && stack_arg_under_construction
2320 && structure_value_addr
== virtual_outgoing_args_rtx
)
2321 ? copy_addr_to_reg (structure_value_addr
)
2322 : structure_value_addr
);
2325 = tree_cons (error_mark_node
,
2326 make_tree (build_pointer_type (TREE_TYPE (funtype
)),
2329 structure_value_addr_parm
= 1;
2332 /* Count the arguments and set NUM_ACTUALS. */
2333 for (p
= actparms
, num_actuals
= 0; p
; p
= TREE_CHAIN (p
))
2336 /* Compute number of named args.
2337 Normally, don't include the last named arg if anonymous args follow.
2338 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2339 (If no anonymous args follow, the result of list_length is actually
2340 one too large. This is harmless.)
2342 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2343 zero, this machine will be able to place unnamed args that were
2344 passed in registers into the stack. So treat all args as named.
2345 This allows the insns emitting for a specific argument list to be
2346 independent of the function declaration.
2348 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2349 reliable way to pass unnamed args in registers, so we must force
2350 them into memory. */
2352 if ((STRICT_ARGUMENT_NAMING
2353 || ! PRETEND_OUTGOING_VARARGS_NAMED
)
2354 && TYPE_ARG_TYPES (funtype
) != 0)
2356 = (list_length (TYPE_ARG_TYPES (funtype
))
2357 /* Don't include the last named arg. */
2358 - (STRICT_ARGUMENT_NAMING
? 0 : 1)
2359 /* Count the struct value address, if it is passed as a parm. */
2360 + structure_value_addr_parm
);
2362 /* If we know nothing, treat all args as named. */
2363 n_named_args
= num_actuals
;
2365 /* Start updating where the next arg would go.
2367 On some machines (such as the PA) indirect calls have a different
2368 calling convention than normal calls. The last argument in
2369 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2371 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, (fndecl
== 0));
2373 /* Make a vector to hold all the information about each arg. */
2374 args
= (struct arg_data
*) alloca (num_actuals
* sizeof (struct arg_data
));
2375 memset ((char *) args
, 0, num_actuals
* sizeof (struct arg_data
));
2377 /* Build up entries in the ARGS array, compute the size of the
2378 arguments into ARGS_SIZE, etc. */
2379 initialize_argument_information (num_actuals
, args
, &args_size
,
2380 n_named_args
, actparms
, fndecl
,
2381 &args_so_far
, reg_parm_stack_space
,
2382 &old_stack_level
, &old_pending_adj
,
2383 &must_preallocate
, &flags
);
2387 /* If this function requires a variable-sized argument list, don't
2388 try to make a cse'able block for this call. We may be able to
2389 do this eventually, but it is too complicated to keep track of
2390 what insns go in the cse'able block and which don't. */
2392 flags
&= ~ECF_LIBCALL_BLOCK
;
2393 must_preallocate
= 1;
2396 /* Now make final decision about preallocating stack space. */
2397 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2401 /* If the structure value address will reference the stack pointer, we
2402 must stabilize it. We don't need to do this if we know that we are
2403 not going to adjust the stack pointer in processing this call. */
2405 if (structure_value_addr
2406 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2407 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2408 structure_value_addr
))
2410 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2411 structure_value_addr
= copy_to_reg (structure_value_addr
);
2413 /* Tail calls can make things harder to debug, and we're traditionally
2414 pushed these optimizations into -O2. Don't try if we're already
2415 expanding a call, as that means we're an argument. Don't try if
2416 there's cleanups, as we know there's code to follow the call.
2418 If rtx_equal_function_value_matters is false, that means we've
2419 finished with regular parsing. Which means that some of the
2420 machinery we use to generate tail-calls is no longer in place.
2421 This is most often true of sjlj-exceptions, which we couldn't
2422 tail-call to anyway. */
2424 if (currently_expanding_call
++ != 0
2425 || !flag_optimize_sibling_calls
2426 || !rtx_equal_function_value_matters
2427 || any_pending_cleanups (1)
2429 try_tail_call
= try_tail_recursion
= 0;
2431 /* Tail recursion fails, when we are not dealing with recursive calls. */
2432 if (!try_tail_recursion
2433 || TREE_CODE (TREE_OPERAND (exp
, 0)) != ADDR_EXPR
2434 || TREE_OPERAND (TREE_OPERAND (exp
, 0), 0) != current_function_decl
)
2435 try_tail_recursion
= 0;
2437 /* Rest of purposes for tail call optimizations to fail. */
2439 #ifdef HAVE_sibcall_epilogue
2440 !HAVE_sibcall_epilogue
2445 /* Doing sibling call optimization needs some work, since
2446 structure_value_addr can be allocated on the stack.
2447 It does not seem worth the effort since few optimizable
2448 sibling calls will return a structure. */
2449 || structure_value_addr
!= NULL_RTX
2450 /* If the register holding the address is a callee saved
2451 register, then we lose. We have no way to prevent that,
2452 so we only allow calls to named functions. */
2453 /* ??? This could be done by having the insn constraints
2454 use a register class that is all call-clobbered. Any
2455 reload insns generated to fix things up would appear
2456 before the sibcall_epilogue. */
2457 || fndecl
== NULL_TREE
2458 || (flags
& (ECF_RETURNS_TWICE
| ECF_LONGJMP
))
2459 || TREE_THIS_VOLATILE (fndecl
)
2460 || !FUNCTION_OK_FOR_SIBCALL (fndecl
)
2461 /* If this function requires more stack slots than the current
2462 function, we cannot change it into a sibling call. */
2463 || args_size
.constant
> current_function_args_size
2464 /* If the callee pops its own arguments, then it must pop exactly
2465 the same number of arguments as the current function. */
2466 || RETURN_POPS_ARGS (fndecl
, funtype
, args_size
.constant
)
2467 != RETURN_POPS_ARGS (current_function_decl
,
2468 TREE_TYPE (current_function_decl
),
2469 current_function_args_size
))
2472 if (try_tail_call
|| try_tail_recursion
)
2475 actparms
= NULL_TREE
;
2476 /* Ok, we're going to give the tail call the old college try.
2477 This means we're going to evaluate the function arguments
2478 up to three times. There are two degrees of badness we can
2479 encounter, those that can be unsaved and those that can't.
2480 (See unsafe_for_reeval commentary for details.)
2482 Generate a new argument list. Pass safe arguments through
2483 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2484 For hard badness, evaluate them now and put their resulting
2485 rtx in a temporary VAR_DECL.
2487 initialize_argument_information has ordered the array for the
2488 order to be pushed, and we must remember this when reconstructing
2489 the original argument order. */
2491 if (PUSH_ARGS_REVERSED
)
2500 i
= num_actuals
- 1;
2504 for (; i
!= end
; i
+= inc
)
2506 switch (unsafe_for_reeval (args
[i
].tree_value
))
2511 case 1: /* Mildly unsafe. */
2512 args
[i
].tree_value
= unsave_expr (args
[i
].tree_value
);
2515 case 2: /* Wildly unsafe. */
2517 tree var
= build_decl (VAR_DECL
, NULL_TREE
,
2518 TREE_TYPE (args
[i
].tree_value
));
2520 expand_expr (args
[i
].tree_value
, NULL_RTX
,
2521 VOIDmode
, EXPAND_NORMAL
));
2522 args
[i
].tree_value
= var
;
2529 /* We need to build actparms for optimize_tail_recursion. We can
2530 safely trash away TREE_PURPOSE, since it is unused by this
2532 if (try_tail_recursion
)
2533 actparms
= tree_cons (NULL_TREE
, args
[i
].tree_value
, actparms
);
2535 /* Expanding one of those dangerous arguments could have added
2536 cleanups, but otherwise give it a whirl. */
2537 if (any_pending_cleanups (1))
2538 try_tail_call
= try_tail_recursion
= 0;
2541 /* Generate a tail recursion sequence when calling ourselves. */
2543 if (try_tail_recursion
)
2545 /* We want to emit any pending stack adjustments before the tail
2546 recursion "call". That way we know any adjustment after the tail
2547 recursion call can be ignored if we indeed use the tail recursion
2549 int save_pending_stack_adjust
= pending_stack_adjust
;
2550 int save_stack_pointer_delta
= stack_pointer_delta
;
2552 /* Emit any queued insns now; otherwise they would end up in
2553 only one of the alternates. */
2556 /* Use a new sequence to hold any RTL we generate. We do not even
2557 know if we will use this RTL yet. The final decision can not be
2558 made until after RTL generation for the entire function is
2561 /* If expanding any of the arguments creates cleanups, we can't
2562 do a tailcall. So, we'll need to pop the pending cleanups
2563 list. If, however, all goes well, and there are no cleanups
2564 then the call to expand_start_target_temps will have no
2566 expand_start_target_temps ();
2567 if (optimize_tail_recursion (actparms
, get_last_insn ()))
2569 if (any_pending_cleanups (1))
2570 try_tail_call
= try_tail_recursion
= 0;
2572 tail_recursion_insns
= get_insns ();
2574 expand_end_target_temps ();
2577 /* Restore the original pending stack adjustment for the sibling and
2578 normal call cases below. */
2579 pending_stack_adjust
= save_pending_stack_adjust
;
2580 stack_pointer_delta
= save_stack_pointer_delta
;
2583 if (profile_arc_flag
&& (flags
& ECF_FORK_OR_EXEC
))
2585 /* A fork duplicates the profile information, and an exec discards
2586 it. We can't rely on fork/exec to be paired. So write out the
2587 profile information we have gathered so far, and clear it. */
2588 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2589 is subject to race conditions, just as with multithreaded
2592 emit_library_call (gen_rtx_SYMBOL_REF (Pmode
, "__bb_fork_func"),
2597 /* Ensure current function's preferred stack boundary is at least
2598 what we need. We don't have to increase alignment for recursive
2600 if (cfun
->preferred_stack_boundary
< preferred_stack_boundary
2601 && fndecl
!= current_function_decl
)
2602 cfun
->preferred_stack_boundary
= preferred_stack_boundary
;
2604 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2606 function_call_count
++;
2608 /* We want to make two insn chains; one for a sibling call, the other
2609 for a normal call. We will select one of the two chains after
2610 initial RTL generation is complete. */
2611 for (pass
= 0; pass
< 2; pass
++)
2613 int sibcall_failure
= 0;
2614 /* We want to emit any pending stack adjustments before the tail
2615 recursion "call". That way we know any adjustment after the tail
2616 recursion call can be ignored if we indeed use the tail recursion
2618 int save_pending_stack_adjust
= 0;
2619 int save_stack_pointer_delta
= 0;
2621 rtx before_call
, next_arg_reg
;
2625 if (! try_tail_call
)
2628 /* Emit any queued insns now; otherwise they would end up in
2629 only one of the alternates. */
2632 /* State variables we need to save and restore between
2634 save_pending_stack_adjust
= pending_stack_adjust
;
2635 save_stack_pointer_delta
= stack_pointer_delta
;
2638 flags
&= ~ECF_SIBCALL
;
2640 flags
|= ECF_SIBCALL
;
2642 /* Other state variables that we must reinitialize each time
2643 through the loop (that are not initialized by the loop itself). */
2647 /* Start a new sequence for the normal call case.
2649 From this point on, if the sibling call fails, we want to set
2650 sibcall_failure instead of continuing the loop. */
2655 /* We know at this point that there are not currently any
2656 pending cleanups. If, however, in the process of evaluating
2657 the arguments we were to create some, we'll need to be
2658 able to get rid of them. */
2659 expand_start_target_temps ();
2662 /* Don't let pending stack adjusts add up to too much.
2663 Also, do all pending adjustments now if there is any chance
2664 this might be a call to alloca or if we are expanding a sibling
2665 call sequence or if we are calling a function that is to return
2666 with stack pointer depressed. */
2667 if (pending_stack_adjust
>= 32
2668 || (pending_stack_adjust
> 0
2669 && (flags
& (ECF_MAY_BE_ALLOCA
| ECF_SP_DEPRESSED
)))
2671 do_pending_stack_adjust ();
2673 /* When calling a const function, we must pop the stack args right away,
2674 so that the pop is deleted or moved with the call. */
2675 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
2678 /* Push the temporary stack slot level so that we can free any
2679 temporaries we make. */
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
;
2714 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2715 sbitmap_zero (stored_args_map
);
2718 /* If we have no actual push instructions, or shouldn't use them,
2719 make space for all args right now. */
2720 else if (adjusted_args_size
.var
!= 0)
2722 if (old_stack_level
== 0)
2724 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
2725 old_pending_adj
= pending_stack_adjust
;
2726 pending_stack_adjust
= 0;
2727 /* stack_arg_under_construction says whether a stack arg is
2728 being constructed at the old stack level. Pushing the stack
2729 gets a clean outgoing argument block. */
2730 old_stack_arg_under_construction
= stack_arg_under_construction
;
2731 stack_arg_under_construction
= 0;
2733 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2737 /* Note that we must go through the motions of allocating an argument
2738 block even if the size is zero because we may be storing args
2739 in the area reserved for register arguments, which may be part of
2742 int needed
= adjusted_args_size
.constant
;
2744 /* Store the maximum argument space used. It will be pushed by
2745 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2748 if (needed
> current_function_outgoing_args_size
)
2749 current_function_outgoing_args_size
= needed
;
2751 if (must_preallocate
)
2753 if (ACCUMULATE_OUTGOING_ARGS
)
2755 /* Since the stack pointer will never be pushed, it is
2756 possible for the evaluation of a parm to clobber
2757 something we have already written to the stack.
2758 Since most function calls on RISC machines do not use
2759 the stack, this is uncommon, but must work correctly.
2761 Therefore, we save any area of the stack that was already
2762 written and that we are using. Here we set up to do this
2763 by making a new stack usage map from the old one. The
2764 actual save will be done by store_one_arg.
2766 Another approach might be to try to reorder the argument
2767 evaluations to avoid this conflicting stack usage. */
2769 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2770 /* Since we will be writing into the entire argument area,
2771 the map must be allocated for its entire size, not just
2772 the part that is the responsibility of the caller. */
2773 needed
+= reg_parm_stack_space
;
2776 #ifdef ARGS_GROW_DOWNWARD
2777 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2780 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2784 = (char *) alloca (highest_outgoing_arg_in_use
);
2786 if (initial_highest_arg_in_use
)
2787 memcpy (stack_usage_map
, initial_stack_usage_map
,
2788 initial_highest_arg_in_use
);
2790 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2791 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2792 (highest_outgoing_arg_in_use
2793 - initial_highest_arg_in_use
));
2796 /* The address of the outgoing argument list must not be
2797 copied to a register here, because argblock would be left
2798 pointing to the wrong place after the call to
2799 allocate_dynamic_stack_space below. */
2801 argblock
= virtual_outgoing_args_rtx
;
2805 if (inhibit_defer_pop
== 0)
2807 /* Try to reuse some or all of the pending_stack_adjust
2808 to get this space. */
2810 = (combine_pending_stack_adjustment_and_call
2811 (unadjusted_args_size
,
2812 &adjusted_args_size
,
2813 preferred_unit_stack_boundary
));
2815 /* combine_pending_stack_adjustment_and_call computes
2816 an adjustment before the arguments are allocated.
2817 Account for them and see whether or not the stack
2818 needs to go up or down. */
2819 needed
= unadjusted_args_size
- needed
;
2823 /* We're releasing stack space. */
2824 /* ??? We can avoid any adjustment at all if we're
2825 already aligned. FIXME. */
2826 pending_stack_adjust
= -needed
;
2827 do_pending_stack_adjust ();
2831 /* We need to allocate space. We'll do that in
2832 push_block below. */
2833 pending_stack_adjust
= 0;
2836 /* Special case this because overhead of `push_block' in
2837 this case is non-trivial. */
2839 argblock
= virtual_outgoing_args_rtx
;
2841 argblock
= push_block (GEN_INT (needed
), 0, 0);
2843 /* We only really need to call `copy_to_reg' in the case
2844 where push insns are going to be used to pass ARGBLOCK
2845 to a function call in ARGS. In that case, the stack
2846 pointer changes value from the allocation point to the
2847 call point, and hence the value of
2848 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2849 as well always do it. */
2850 argblock
= copy_to_reg (argblock
);
2852 /* The save/restore code in store_one_arg handles all
2853 cases except one: a constructor call (including a C
2854 function returning a BLKmode struct) to initialize
2856 if (stack_arg_under_construction
)
2858 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2859 rtx push_size
= GEN_INT (reg_parm_stack_space
2860 + adjusted_args_size
.constant
);
2862 rtx push_size
= GEN_INT (adjusted_args_size
.constant
);
2864 if (old_stack_level
== 0)
2866 emit_stack_save (SAVE_BLOCK
, &old_stack_level
,
2868 old_pending_adj
= pending_stack_adjust
;
2869 pending_stack_adjust
= 0;
2870 /* stack_arg_under_construction says whether a stack
2871 arg is being constructed at the old stack level.
2872 Pushing the stack gets a clean outgoing argument
2874 old_stack_arg_under_construction
2875 = stack_arg_under_construction
;
2876 stack_arg_under_construction
= 0;
2877 /* Make a new map for the new argument list. */
2878 stack_usage_map
= (char *)
2879 alloca (highest_outgoing_arg_in_use
);
2880 memset (stack_usage_map
, 0, highest_outgoing_arg_in_use
);
2881 highest_outgoing_arg_in_use
= 0;
2883 allocate_dynamic_stack_space (push_size
, NULL_RTX
,
2886 /* If argument evaluation might modify the stack pointer,
2887 copy the address of the argument list to a register. */
2888 for (i
= 0; i
< num_actuals
; i
++)
2889 if (args
[i
].pass_on_stack
)
2891 argblock
= copy_addr_to_reg (argblock
);
2898 compute_argument_addresses (args
, argblock
, num_actuals
);
2900 /* If we push args individually in reverse order, perform stack alignment
2901 before the first push (the last arg). */
2902 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2903 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2905 /* When the stack adjustment is pending, we get better code
2906 by combining the adjustments. */
2907 if (pending_stack_adjust
2908 && ! (flags
& ECF_LIBCALL_BLOCK
)
2909 && ! inhibit_defer_pop
)
2911 pending_stack_adjust
2912 = (combine_pending_stack_adjustment_and_call
2913 (unadjusted_args_size
,
2914 &adjusted_args_size
,
2915 preferred_unit_stack_boundary
));
2916 do_pending_stack_adjust ();
2918 else if (argblock
== 0)
2919 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2920 - unadjusted_args_size
));
2922 /* Now that the stack is properly aligned, pops can't safely
2923 be deferred during the evaluation of the arguments. */
2926 funexp
= rtx_for_function_call (fndecl
, exp
);
2928 /* Figure out the register where the value, if any, will come back. */
2930 if (TYPE_MODE (TREE_TYPE (exp
)) != VOIDmode
2931 && ! structure_value_addr
)
2933 if (pcc_struct_value
)
2934 valreg
= hard_function_value (build_pointer_type (TREE_TYPE (exp
)),
2935 fndecl
, (pass
== 0));
2937 valreg
= hard_function_value (TREE_TYPE (exp
), fndecl
, (pass
== 0));
2940 /* Precompute all register parameters. It isn't safe to compute anything
2941 once we have started filling any specific hard regs. */
2942 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2944 #ifdef REG_PARM_STACK_SPACE
2945 /* Save the fixed argument area if it's part of the caller's frame and
2946 is clobbered by argument setup for this call. */
2947 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2948 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2949 &low_to_save
, &high_to_save
);
2952 /* Now store (and compute if necessary) all non-register parms.
2953 These come before register parms, since they can require block-moves,
2954 which could clobber the registers used for register parms.
2955 Parms which have partial registers are not stored here,
2956 but we do preallocate space here if they want that. */
2958 for (i
= 0; i
< num_actuals
; i
++)
2959 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2961 rtx before_arg
= get_last_insn ();
2963 if (store_one_arg (&args
[i
], argblock
, flags
,
2964 adjusted_args_size
.var
!= 0,
2965 reg_parm_stack_space
)
2967 && check_sibcall_argument_overlap (before_arg
,
2969 sibcall_failure
= 1;
2972 /* If we have a parm that is passed in registers but not in memory
2973 and whose alignment does not permit a direct copy into registers,
2974 make a group of pseudos that correspond to each register that we
2976 if (STRICT_ALIGNMENT
)
2977 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2979 /* Now store any partially-in-registers parm.
2980 This is the last place a block-move can happen. */
2982 for (i
= 0; i
< num_actuals
; i
++)
2983 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2985 rtx before_arg
= get_last_insn ();
2987 if (store_one_arg (&args
[i
], argblock
, flags
,
2988 adjusted_args_size
.var
!= 0,
2989 reg_parm_stack_space
)
2991 && check_sibcall_argument_overlap (before_arg
,
2993 sibcall_failure
= 1;
2996 /* If we pushed args in forward order, perform stack alignment
2997 after pushing the last arg. */
2998 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
2999 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
3000 - unadjusted_args_size
));
3002 /* If register arguments require space on the stack and stack space
3003 was not preallocated, allocate stack space here for arguments
3004 passed in registers. */
3005 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3006 if (!ACCUMULATE_OUTGOING_ARGS
3007 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
3008 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
3011 /* Pass the function the address in which to return a
3013 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
3015 emit_move_insn (struct_value_rtx
,
3017 force_operand (structure_value_addr
,
3020 if (GET_CODE (struct_value_rtx
) == REG
)
3021 use_reg (&call_fusage
, struct_value_rtx
);
3024 funexp
= prepare_call_address (funexp
, fndecl
, &call_fusage
,
3025 reg_parm_seen
, pass
== 0);
3027 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
);
3029 /* Perform postincrements before actually calling the function. */
3032 /* Save a pointer to the last insn before the call, so that we can
3033 later safely search backwards to find the CALL_INSN. */
3034 before_call
= get_last_insn ();
3036 /* Set up next argument register. For sibling calls on machines
3037 with register windows this should be the incoming register. */
3038 #ifdef FUNCTION_INCOMING_ARG
3040 next_arg_reg
= FUNCTION_INCOMING_ARG (args_so_far
, VOIDmode
,
3044 next_arg_reg
= FUNCTION_ARG (args_so_far
, VOIDmode
,
3047 /* All arguments and registers used for the call must be set up by
3050 /* Stack must be properly aligned now. */
3051 if (pass
&& stack_pointer_delta
% preferred_unit_stack_boundary
)
3054 /* Generate the actual call instruction. */
3055 emit_call_1 (funexp
, fndecl
, funtype
, unadjusted_args_size
,
3056 adjusted_args_size
.constant
, struct_value_size
,
3057 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
3060 /* Verify that we've deallocated all the stack we used. */
3062 && old_stack_allocated
!= stack_pointer_delta
- pending_stack_adjust
)
3065 /* If call is cse'able, make appropriate pair of reg-notes around it.
3066 Test valreg so we don't crash; may safely ignore `const'
3067 if return type is void. Disable for PARALLEL return values, because
3068 we have no way to move such values into a pseudo register. */
3069 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
3073 if (valreg
== 0 || GET_CODE (valreg
) == PARALLEL
)
3075 insns
= get_insns ();
3082 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
3084 /* Mark the return value as a pointer if needed. */
3085 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
3086 mark_reg_pointer (temp
,
3087 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp
))));
3089 /* Construct an "equal form" for the value which mentions all the
3090 arguments in order as well as the function name. */
3091 for (i
= 0; i
< num_actuals
; i
++)
3092 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3093 args
[i
].initial_value
, note
);
3094 note
= gen_rtx_EXPR_LIST (VOIDmode
, funexp
, note
);
3096 insns
= get_insns ();
3099 if (flags
& ECF_PURE
)
3100 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3101 gen_rtx_USE (VOIDmode
,
3102 gen_rtx_MEM (BLKmode
,
3103 gen_rtx_SCRATCH (VOIDmode
))),
3106 emit_libcall_block (insns
, temp
, valreg
, note
);
3111 else if (pass
&& (flags
& ECF_MALLOC
))
3113 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
3116 /* The return value from a malloc-like function is a pointer. */
3117 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
3118 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
3120 emit_move_insn (temp
, valreg
);
3122 /* The return value from a malloc-like function can not alias
3124 last
= get_last_insn ();
3126 gen_rtx_EXPR_LIST (REG_NOALIAS
, temp
, REG_NOTES (last
));
3128 /* Write out the sequence. */
3129 insns
= get_insns ();
3135 /* For calls to `setjmp', etc., inform flow.c it should complain
3136 if nonvolatile values are live. For functions that cannot return,
3137 inform flow that control does not fall through. */
3139 if ((flags
& (ECF_NORETURN
| ECF_LONGJMP
)) || pass
== 0)
3141 /* The barrier must be emitted
3142 immediately after the CALL_INSN. Some ports emit more
3143 than just a CALL_INSN above, so we must search for it here. */
3145 rtx last
= get_last_insn ();
3146 while (GET_CODE (last
) != CALL_INSN
)
3148 last
= PREV_INSN (last
);
3149 /* There was no CALL_INSN? */
3150 if (last
== before_call
)
3154 emit_barrier_after (last
);
3157 if (flags
& ECF_LONGJMP
)
3158 current_function_calls_longjmp
= 1;
3160 /* If this function is returning into a memory location marked as
3161 readonly, it means it is initializing that location. But we normally
3162 treat functions as not clobbering such locations, so we need to
3163 specify that this one does. */
3164 if (target
!= 0 && GET_CODE (target
) == MEM
3165 && structure_value_addr
!= 0 && RTX_UNCHANGING_P (target
))
3166 emit_insn (gen_rtx_CLOBBER (VOIDmode
, target
));
3168 /* If value type not void, return an rtx for the value. */
3170 /* If there are cleanups to be called, don't use a hard reg as target.
3171 We need to double check this and see if it matters anymore. */
3172 if (any_pending_cleanups (1))
3174 if (target
&& REG_P (target
)
3175 && REGNO (target
) < FIRST_PSEUDO_REGISTER
)
3177 sibcall_failure
= 1;
3180 if (TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
3182 target
= const0_rtx
;
3183 else if (structure_value_addr
)
3185 if (target
== 0 || GET_CODE (target
) != MEM
)
3188 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
3189 memory_address (TYPE_MODE (TREE_TYPE (exp
)),
3190 structure_value_addr
));
3191 set_mem_attributes (target
, exp
, 1);
3194 else if (pcc_struct_value
)
3196 /* This is the special C++ case where we need to
3197 know what the true target was. We take care to
3198 never use this value more than once in one expression. */
3199 target
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
3200 copy_to_reg (valreg
));
3201 set_mem_attributes (target
, exp
, 1);
3203 /* Handle calls that return values in multiple non-contiguous locations.
3204 The Irix 6 ABI has examples of this. */
3205 else if (GET_CODE (valreg
) == PARALLEL
)
3209 /* This will only be assigned once, so it can be readonly. */
3210 tree nt
= build_qualified_type (TREE_TYPE (exp
),
3211 (TYPE_QUALS (TREE_TYPE (exp
))
3212 | TYPE_QUAL_CONST
));
3214 target
= assign_temp (nt
, 0, 1, 1);
3215 preserve_temp_slots (target
);
3218 if (! rtx_equal_p (target
, valreg
))
3219 emit_group_store (target
, valreg
,
3220 int_size_in_bytes (TREE_TYPE (exp
)));
3222 /* We can not support sibling calls for this case. */
3223 sibcall_failure
= 1;
3226 && GET_MODE (target
) == TYPE_MODE (TREE_TYPE (exp
))
3227 && GET_MODE (target
) == GET_MODE (valreg
))
3229 /* TARGET and VALREG cannot be equal at this point because the
3230 latter would not have REG_FUNCTION_VALUE_P true, while the
3231 former would if it were referring to the same register.
3233 If they refer to the same register, this move will be a no-op,
3234 except when function inlining is being done. */
3235 emit_move_insn (target
, valreg
);
3237 else if (TYPE_MODE (TREE_TYPE (exp
)) == BLKmode
)
3239 target
= copy_blkmode_from_reg (target
, valreg
, TREE_TYPE (exp
));
3241 /* We can not support sibling calls for this case. */
3242 sibcall_failure
= 1;
3245 target
= copy_to_reg (valreg
);
3247 #ifdef PROMOTE_FUNCTION_RETURN
3248 /* If we promoted this return value, make the proper SUBREG. TARGET
3249 might be const0_rtx here, so be careful. */
3250 if (GET_CODE (target
) == REG
3251 && TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
3252 && GET_MODE (target
) != TYPE_MODE (TREE_TYPE (exp
)))
3254 tree type
= TREE_TYPE (exp
);
3255 int unsignedp
= TREE_UNSIGNED (type
);
3258 /* If we don't promote as expected, something is wrong. */
3259 if (GET_MODE (target
)
3260 != promote_mode (type
, TYPE_MODE (type
), &unsignedp
, 1))
3263 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
3264 && GET_MODE_SIZE (GET_MODE (target
))
3265 > GET_MODE_SIZE (TYPE_MODE (type
)))
3267 offset
= GET_MODE_SIZE (GET_MODE (target
))
3268 - GET_MODE_SIZE (TYPE_MODE (type
));
3269 if (! BYTES_BIG_ENDIAN
)
3270 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
3271 else if (! WORDS_BIG_ENDIAN
)
3272 offset
%= UNITS_PER_WORD
;
3274 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
3275 SUBREG_PROMOTED_VAR_P (target
) = 1;
3276 SUBREG_PROMOTED_UNSIGNED_P (target
) = unsignedp
;
3280 /* If size of args is variable or this was a constructor call for a stack
3281 argument, restore saved stack-pointer value. */
3283 if (old_stack_level
&& ! (flags
& ECF_SP_DEPRESSED
))
3285 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
3286 pending_stack_adjust
= old_pending_adj
;
3287 stack_arg_under_construction
= old_stack_arg_under_construction
;
3288 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3289 stack_usage_map
= initial_stack_usage_map
;
3290 sibcall_failure
= 1;
3292 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
3294 #ifdef REG_PARM_STACK_SPACE
3297 restore_fixed_argument_area (save_area
, argblock
,
3298 high_to_save
, low_to_save
);
3302 /* If we saved any argument areas, restore them. */
3303 for (i
= 0; i
< num_actuals
; i
++)
3304 if (args
[i
].save_area
)
3306 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
3308 = gen_rtx_MEM (save_mode
,
3309 memory_address (save_mode
,
3310 XEXP (args
[i
].stack_slot
, 0)));
3312 if (save_mode
!= BLKmode
)
3313 emit_move_insn (stack_area
, args
[i
].save_area
);
3315 emit_block_move (stack_area
,
3316 validize_mem (args
[i
].save_area
),
3317 GEN_INT (args
[i
].size
.constant
));
3320 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3321 stack_usage_map
= initial_stack_usage_map
;
3324 /* If this was alloca, record the new stack level for nonlocal gotos.
3325 Check for the handler slots since we might not have a save area
3326 for non-local gotos. */
3328 if ((flags
& ECF_MAY_BE_ALLOCA
) && nonlocal_goto_handler_slots
!= 0)
3329 emit_stack_save (SAVE_NONLOCAL
, &nonlocal_goto_stack_level
, NULL_RTX
);
3333 /* Free up storage we no longer need. */
3334 for (i
= 0; i
< num_actuals
; ++i
)
3335 if (args
[i
].aligned_regs
)
3336 free (args
[i
].aligned_regs
);
3340 /* Undo the fake expand_start_target_temps we did earlier. If
3341 there had been any cleanups created, we've already set
3343 expand_end_target_temps ();
3346 insns
= get_insns ();
3351 tail_call_insns
= insns
;
3353 /* Restore the pending stack adjustment now that we have
3354 finished generating the sibling call sequence. */
3356 pending_stack_adjust
= save_pending_stack_adjust
;
3357 stack_pointer_delta
= save_stack_pointer_delta
;
3359 /* Prepare arg structure for next iteration. */
3360 for (i
= 0; i
< num_actuals
; i
++)
3363 args
[i
].aligned_regs
= 0;
3367 sbitmap_free (stored_args_map
);
3370 normal_call_insns
= insns
;
3372 /* If something prevents making this a sibling call,
3373 zero out the sequence. */
3374 if (sibcall_failure
)
3375 tail_call_insns
= NULL_RTX
;
3378 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3379 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3380 can happen if the arguments to this function call an inline
3381 function who's expansion contains another CALL_PLACEHOLDER.
3383 If there are any C_Ps in any of these sequences, replace them
3384 with their normal call. */
3386 for (insn
= normal_call_insns
; insn
; insn
= NEXT_INSN (insn
))
3387 if (GET_CODE (insn
) == CALL_INSN
3388 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3389 replace_call_placeholder (insn
, sibcall_use_normal
);
3391 for (insn
= tail_call_insns
; insn
; insn
= NEXT_INSN (insn
))
3392 if (GET_CODE (insn
) == CALL_INSN
3393 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3394 replace_call_placeholder (insn
, sibcall_use_normal
);
3396 for (insn
= tail_recursion_insns
; insn
; insn
= NEXT_INSN (insn
))
3397 if (GET_CODE (insn
) == CALL_INSN
3398 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3399 replace_call_placeholder (insn
, sibcall_use_normal
);
3401 /* If this was a potential tail recursion site, then emit a
3402 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3403 One of them will be selected later. */
3404 if (tail_recursion_insns
|| tail_call_insns
)
3406 /* The tail recursion label must be kept around. We could expose
3407 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3408 and makes determining true tail recursion sites difficult.
3410 So we set LABEL_PRESERVE_P here, then clear it when we select
3411 one of the call sequences after rtl generation is complete. */
3412 if (tail_recursion_insns
)
3413 LABEL_PRESERVE_P (tail_recursion_label
) = 1;
3414 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode
, normal_call_insns
,
3416 tail_recursion_insns
,
3417 tail_recursion_label
));
3420 emit_insns (normal_call_insns
);
3422 currently_expanding_call
--;
3424 /* If this function returns with the stack pointer depressed, ensure
3425 this block saves and restores the stack pointer, show it was
3426 changed, and adjust for any outgoing arg space. */
3427 if (flags
& ECF_SP_DEPRESSED
)
3429 clear_pending_stack_adjust ();
3430 emit_insn (gen_rtx (CLOBBER
, VOIDmode
, stack_pointer_rtx
));
3431 emit_move_insn (virtual_stack_dynamic_rtx
, stack_pointer_rtx
);
3432 save_stack_pointer ();
3438 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3439 The RETVAL parameter specifies whether return value needs to be saved, other
3440 parameters are documented in the emit_library_call function below. */
3443 emit_library_call_value_1 (retval
, orgfun
, value
, fn_type
, outmode
, nargs
, p
)
3447 enum libcall_type fn_type
;
3448 enum machine_mode outmode
;
3452 /* Total size in bytes of all the stack-parms scanned so far. */
3453 struct args_size args_size
;
3454 /* Size of arguments before any adjustments (such as rounding). */
3455 struct args_size original_args_size
;
3460 struct args_size alignment_pad
;
3462 CUMULATIVE_ARGS args_so_far
;
3466 enum machine_mode mode
;
3469 struct args_size offset
;
3470 struct args_size size
;
3474 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3475 rtx call_fusage
= 0;
3478 int pcc_struct_value
= 0;
3479 int struct_value_size
= 0;
3481 int reg_parm_stack_space
= 0;
3485 #ifdef REG_PARM_STACK_SPACE
3486 /* Define the boundary of the register parm stack space that needs to be
3488 int low_to_save
= -1, high_to_save
= 0;
3489 rtx save_area
= 0; /* Place that it is saved. */
3492 /* Size of the stack reserved for parameter registers. */
3493 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3494 char *initial_stack_usage_map
= stack_usage_map
;
3496 #ifdef REG_PARM_STACK_SPACE
3497 #ifdef MAYBE_REG_PARM_STACK_SPACE
3498 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
3500 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3504 /* By default, library functions can not throw. */
3505 flags
= ECF_NOTHROW
;
3517 case LCT_CONST_MAKE_BLOCK
:
3518 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
3520 case LCT_PURE_MAKE_BLOCK
:
3521 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
3524 flags
|= ECF_NORETURN
;
3527 flags
= ECF_NORETURN
;
3529 case LCT_ALWAYS_RETURN
:
3530 flags
= ECF_ALWAYS_RETURN
;
3532 case LCT_RETURNS_TWICE
:
3533 flags
= ECF_RETURNS_TWICE
;
3538 /* Ensure current function's preferred stack boundary is at least
3540 if (cfun
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3541 cfun
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3543 /* If this kind of value comes back in memory,
3544 decide where in memory it should come back. */
3545 if (outmode
!= VOIDmode
&& aggregate_value_p (type_for_mode (outmode
, 0)))
3547 #ifdef PCC_STATIC_STRUCT_RETURN
3549 = hard_function_value (build_pointer_type (type_for_mode (outmode
, 0)),
3551 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3552 pcc_struct_value
= 1;
3554 value
= gen_reg_rtx (outmode
);
3555 #else /* not PCC_STATIC_STRUCT_RETURN */
3556 struct_value_size
= GET_MODE_SIZE (outmode
);
3557 if (value
!= 0 && GET_CODE (value
) == MEM
)
3560 mem_value
= assign_temp (type_for_mode (outmode
, 0), 0, 1, 1);
3563 /* This call returns a big structure. */
3564 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3567 /* ??? Unfinished: must pass the memory address as an argument. */
3569 /* Copy all the libcall-arguments out of the varargs data
3570 and into a vector ARGVEC.
3572 Compute how to pass each argument. We only support a very small subset
3573 of the full argument passing conventions to limit complexity here since
3574 library functions shouldn't have many args. */
3576 argvec
= (struct arg
*) alloca ((nargs
+ 1) * sizeof (struct arg
));
3577 memset ((char *) argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3579 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3580 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3582 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0);
3585 args_size
.constant
= 0;
3590 /* Now we are about to start emitting insns that can be deleted
3591 if a libcall is deleted. */
3592 if (flags
& ECF_LIBCALL_BLOCK
)
3597 /* If there's a structure value address to be passed,
3598 either pass it in the special place, or pass it as an extra argument. */
3599 if (mem_value
&& struct_value_rtx
== 0 && ! pcc_struct_value
)
3601 rtx addr
= XEXP (mem_value
, 0);
3604 /* Make sure it is a reasonable operand for a move or push insn. */
3605 if (GET_CODE (addr
) != REG
&& GET_CODE (addr
) != MEM
3606 && ! (CONSTANT_P (addr
) && LEGITIMATE_CONSTANT_P (addr
)))
3607 addr
= force_operand (addr
, NULL_RTX
);
3609 argvec
[count
].value
= addr
;
3610 argvec
[count
].mode
= Pmode
;
3611 argvec
[count
].partial
= 0;
3613 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, Pmode
, NULL_TREE
, 1);
3614 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3615 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, Pmode
, NULL_TREE
, 1))
3619 locate_and_pad_parm (Pmode
, NULL_TREE
,
3620 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3623 argvec
[count
].reg
!= 0,
3625 NULL_TREE
, &args_size
, &argvec
[count
].offset
,
3626 &argvec
[count
].size
, &alignment_pad
);
3628 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3629 || reg_parm_stack_space
> 0)
3630 args_size
.constant
+= argvec
[count
].size
.constant
;
3632 FUNCTION_ARG_ADVANCE (args_so_far
, Pmode
, (tree
) 0, 1);
3637 for (; count
< nargs
; count
++)
3639 rtx val
= va_arg (p
, rtx
);
3640 enum machine_mode mode
= va_arg (p
, enum machine_mode
);
3642 /* We cannot convert the arg value to the mode the library wants here;
3643 must do it earlier where we know the signedness of the arg. */
3645 || (GET_MODE (val
) != mode
&& GET_MODE (val
) != VOIDmode
))
3648 /* On some machines, there's no way to pass a float to a library fcn.
3649 Pass it as a double instead. */
3650 #ifdef LIBGCC_NEEDS_DOUBLE
3651 if (LIBGCC_NEEDS_DOUBLE
&& mode
== SFmode
)
3652 val
= convert_modes (DFmode
, SFmode
, val
, 0), mode
= DFmode
;
3655 /* There's no need to call protect_from_queue, because
3656 either emit_move_insn or emit_push_insn will do that. */
3658 /* Make sure it is a reasonable operand for a move or push insn. */
3659 if (GET_CODE (val
) != REG
&& GET_CODE (val
) != MEM
3660 && ! (CONSTANT_P (val
) && LEGITIMATE_CONSTANT_P (val
)))
3661 val
= force_operand (val
, NULL_RTX
);
3663 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3664 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far
, mode
, NULL_TREE
, 1))
3668 #ifdef FUNCTION_ARG_CALLEE_COPIES
3669 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far
, mode
,
3674 if (GET_MODE (val
) == MEM
&& ! must_copy
)
3678 slot
= assign_temp (type_for_mode (mode
, 0), 0, 1, 1);
3679 emit_move_insn (slot
, val
);
3683 tree type
= type_for_mode (mode
, 0);
3685 slot
= gen_rtx_MEM (mode
,
3686 expand_expr (build1 (ADDR_EXPR
,
3689 make_tree (type
, val
)),
3690 NULL_RTX
, VOIDmode
, 0));
3693 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3694 gen_rtx_USE (VOIDmode
, slot
),
3697 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3698 gen_rtx_CLOBBER (VOIDmode
,
3703 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3707 argvec
[count
].value
= val
;
3708 argvec
[count
].mode
= mode
;
3710 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, mode
, NULL_TREE
, 1);
3712 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3713 argvec
[count
].partial
3714 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, mode
, NULL_TREE
, 1);
3716 argvec
[count
].partial
= 0;
3719 locate_and_pad_parm (mode
, NULL_TREE
,
3720 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3723 argvec
[count
].reg
!= 0,
3725 NULL_TREE
, &args_size
, &argvec
[count
].offset
,
3726 &argvec
[count
].size
, &alignment_pad
);
3728 if (argvec
[count
].size
.var
)
3731 if (reg_parm_stack_space
== 0 && argvec
[count
].partial
)
3732 argvec
[count
].size
.constant
-= argvec
[count
].partial
* UNITS_PER_WORD
;
3734 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3735 || reg_parm_stack_space
> 0)
3736 args_size
.constant
+= argvec
[count
].size
.constant
;
3738 FUNCTION_ARG_ADVANCE (args_so_far
, mode
, (tree
) 0, 1);
3741 #ifdef FINAL_REG_PARM_STACK_SPACE
3742 reg_parm_stack_space
= FINAL_REG_PARM_STACK_SPACE (args_size
.constant
,
3745 /* If this machine requires an external definition for library
3746 functions, write one out. */
3747 assemble_external_libcall (fun
);
3749 original_args_size
= args_size
;
3750 args_size
.constant
= (((args_size
.constant
3751 + stack_pointer_delta
3755 - stack_pointer_delta
);
3757 args_size
.constant
= MAX (args_size
.constant
,
3758 reg_parm_stack_space
);
3760 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3761 args_size
.constant
-= reg_parm_stack_space
;
3764 if (args_size
.constant
> current_function_outgoing_args_size
)
3765 current_function_outgoing_args_size
= args_size
.constant
;
3767 if (ACCUMULATE_OUTGOING_ARGS
)
3769 /* Since the stack pointer will never be pushed, it is possible for
3770 the evaluation of a parm to clobber something we have already
3771 written to the stack. Since most function calls on RISC machines
3772 do not use the stack, this is uncommon, but must work correctly.
3774 Therefore, we save any area of the stack that was already written
3775 and that we are using. Here we set up to do this by making a new
3776 stack usage map from the old one.
3778 Another approach might be to try to reorder the argument
3779 evaluations to avoid this conflicting stack usage. */
3781 needed
= args_size
.constant
;
3783 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3784 /* Since we will be writing into the entire argument area, the
3785 map must be allocated for its entire size, not just the part that
3786 is the responsibility of the caller. */
3787 needed
+= reg_parm_stack_space
;
3790 #ifdef ARGS_GROW_DOWNWARD
3791 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3794 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3797 stack_usage_map
= (char *) alloca (highest_outgoing_arg_in_use
);
3799 if (initial_highest_arg_in_use
)
3800 memcpy (stack_usage_map
, initial_stack_usage_map
,
3801 initial_highest_arg_in_use
);
3803 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3804 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3805 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3808 /* We must be careful to use virtual regs before they're instantiated,
3809 and real regs afterwards. Loop optimization, for example, can create
3810 new libcalls after we've instantiated the virtual regs, and if we
3811 use virtuals anyway, they won't match the rtl patterns. */
3813 if (virtuals_instantiated
)
3814 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3816 argblock
= virtual_outgoing_args_rtx
;
3821 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3824 /* If we push args individually in reverse order, perform stack alignment
3825 before the first push (the last arg). */
3826 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3827 anti_adjust_stack (GEN_INT (args_size
.constant
3828 - original_args_size
.constant
));
3830 if (PUSH_ARGS_REVERSED
)
3841 #ifdef REG_PARM_STACK_SPACE
3842 if (ACCUMULATE_OUTGOING_ARGS
)
3844 /* The argument list is the property of the called routine and it
3845 may clobber it. If the fixed area has been used for previous
3846 parameters, we must save and restore it.
3848 Here we compute the boundary of the that needs to be saved, if any. */
3850 #ifdef ARGS_GROW_DOWNWARD
3851 for (count
= 0; count
< reg_parm_stack_space
+ 1; count
++)
3853 for (count
= 0; count
< reg_parm_stack_space
; count
++)
3856 if (count
>= highest_outgoing_arg_in_use
3857 || stack_usage_map
[count
] == 0)
3860 if (low_to_save
== -1)
3861 low_to_save
= count
;
3863 high_to_save
= count
;
3866 if (low_to_save
>= 0)
3868 int num_to_save
= high_to_save
- low_to_save
+ 1;
3869 enum machine_mode save_mode
3870 = mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
3873 /* If we don't have the required alignment, must do this in BLKmode. */
3874 if ((low_to_save
& (MIN (GET_MODE_SIZE (save_mode
),
3875 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
3876 save_mode
= BLKmode
;
3878 #ifdef ARGS_GROW_DOWNWARD
3879 stack_area
= gen_rtx_MEM (save_mode
,
3880 memory_address (save_mode
,
3881 plus_constant (argblock
,
3884 stack_area
= gen_rtx_MEM (save_mode
,
3885 memory_address (save_mode
,
3886 plus_constant (argblock
,
3889 if (save_mode
== BLKmode
)
3891 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
3892 set_mem_align (save_area
, PARM_BOUNDARY
);
3893 emit_block_move (validize_mem (save_area
), stack_area
,
3894 GEN_INT (num_to_save
));
3898 save_area
= gen_reg_rtx (save_mode
);
3899 emit_move_insn (save_area
, stack_area
);
3905 /* Push the args that need to be pushed. */
3907 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3908 are to be pushed. */
3909 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3911 enum machine_mode mode
= argvec
[argnum
].mode
;
3912 rtx val
= argvec
[argnum
].value
;
3913 rtx reg
= argvec
[argnum
].reg
;
3914 int partial
= argvec
[argnum
].partial
;
3915 int lower_bound
= 0, upper_bound
= 0, i
;
3917 if (! (reg
!= 0 && partial
== 0))
3919 if (ACCUMULATE_OUTGOING_ARGS
)
3921 /* If this is being stored into a pre-allocated, fixed-size,
3922 stack area, save any previous data at that location. */
3924 #ifdef ARGS_GROW_DOWNWARD
3925 /* stack_slot is negative, but we want to index stack_usage_map
3926 with positive values. */
3927 upper_bound
= -argvec
[argnum
].offset
.constant
+ 1;
3928 lower_bound
= upper_bound
- argvec
[argnum
].size
.constant
;
3930 lower_bound
= argvec
[argnum
].offset
.constant
;
3931 upper_bound
= lower_bound
+ argvec
[argnum
].size
.constant
;
3934 for (i
= lower_bound
; i
< upper_bound
; i
++)
3935 if (stack_usage_map
[i
]
3936 /* Don't store things in the fixed argument area at this
3937 point; it has already been saved. */
3938 && i
> reg_parm_stack_space
)
3941 if (i
!= upper_bound
)
3943 /* We need to make a save area. See what mode we can make
3945 enum machine_mode save_mode
3946 = mode_for_size (argvec
[argnum
].size
.constant
3954 plus_constant (argblock
,
3955 argvec
[argnum
].offset
.constant
)));
3956 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3958 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3962 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, 0, partial
, reg
, 0,
3963 argblock
, GEN_INT (argvec
[argnum
].offset
.constant
),
3964 reg_parm_stack_space
, ARGS_SIZE_RTX (alignment_pad
));
3966 /* Now mark the segment we just used. */
3967 if (ACCUMULATE_OUTGOING_ARGS
)
3968 for (i
= lower_bound
; i
< upper_bound
; i
++)
3969 stack_usage_map
[i
] = 1;
3975 /* If we pushed args in forward order, perform stack alignment
3976 after pushing the last arg. */
3977 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3978 anti_adjust_stack (GEN_INT (args_size
.constant
3979 - original_args_size
.constant
));
3981 if (PUSH_ARGS_REVERSED
)
3986 fun
= prepare_call_address (fun
, NULL_TREE
, &call_fusage
, 0, 0);
3988 /* Now load any reg parms into their regs. */
3990 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3991 are to be pushed. */
3992 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3994 rtx val
= argvec
[argnum
].value
;
3995 rtx reg
= argvec
[argnum
].reg
;
3996 int partial
= argvec
[argnum
].partial
;
3998 /* Handle calls that pass values in multiple non-contiguous
3999 locations. The PA64 has examples of this for library calls. */
4000 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
4001 emit_group_load (reg
, val
, GET_MODE_SIZE (GET_MODE (val
)));
4002 else if (reg
!= 0 && partial
== 0)
4003 emit_move_insn (reg
, val
);
4008 /* Any regs containing parms remain in use through the call. */
4009 for (count
= 0; count
< nargs
; count
++)
4011 rtx reg
= argvec
[count
].reg
;
4012 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
4013 use_group_regs (&call_fusage
, reg
);
4015 use_reg (&call_fusage
, reg
);
4018 /* Pass the function the address in which to return a structure value. */
4019 if (mem_value
!= 0 && struct_value_rtx
!= 0 && ! pcc_struct_value
)
4021 emit_move_insn (struct_value_rtx
,
4023 force_operand (XEXP (mem_value
, 0),
4025 if (GET_CODE (struct_value_rtx
) == REG
)
4026 use_reg (&call_fusage
, struct_value_rtx
);
4029 /* Don't allow popping to be deferred, since then
4030 cse'ing of library calls could delete a call and leave the pop. */
4032 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
4033 ? hard_libcall_value (outmode
) : NULL_RTX
);
4035 /* Stack must be properly aligned now. */
4036 if (stack_pointer_delta
& (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1))
4039 before_call
= get_last_insn ();
4041 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4042 will set inhibit_defer_pop to that value. */
4043 /* The return type is needed to decide how many bytes the function pops.
4044 Signedness plays no role in that, so for simplicity, we pretend it's
4045 always signed. We also assume that the list of arguments passed has
4046 no impact, so we pretend it is unknown. */
4049 get_identifier (XSTR (orgfun
, 0)),
4050 build_function_type (outmode
== VOIDmode
? void_type_node
4051 : type_for_mode (outmode
, 0), NULL_TREE
),
4052 original_args_size
.constant
, args_size
.constant
,
4054 FUNCTION_ARG (args_so_far
, VOIDmode
, void_type_node
, 1),
4056 old_inhibit_defer_pop
+ 1, call_fusage
, flags
);
4058 /* For calls to `setjmp', etc., inform flow.c it should complain
4059 if nonvolatile values are live. For functions that cannot return,
4060 inform flow that control does not fall through. */
4062 if (flags
& (ECF_NORETURN
| ECF_LONGJMP
))
4064 /* The barrier note must be emitted
4065 immediately after the CALL_INSN. Some ports emit more than
4066 just a CALL_INSN above, so we must search for it here. */
4068 rtx last
= get_last_insn ();
4069 while (GET_CODE (last
) != CALL_INSN
)
4071 last
= PREV_INSN (last
);
4072 /* There was no CALL_INSN? */
4073 if (last
== before_call
)
4077 emit_barrier_after (last
);
4080 /* Now restore inhibit_defer_pop to its actual original value. */
4083 /* If call is cse'able, make appropriate pair of reg-notes around it.
4084 Test valreg so we don't crash; may safely ignore `const'
4085 if return type is void. Disable for PARALLEL return values, because
4086 we have no way to move such values into a pseudo register. */
4087 if (flags
& ECF_LIBCALL_BLOCK
)
4091 if (valreg
== 0 || GET_CODE (valreg
) == PARALLEL
)
4093 insns
= get_insns ();
4100 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
4103 /* Construct an "equal form" for the value which mentions all the
4104 arguments in order as well as the function name. */
4105 for (i
= 0; i
< nargs
; i
++)
4106 note
= gen_rtx_EXPR_LIST (VOIDmode
, argvec
[i
].value
, note
);
4107 note
= gen_rtx_EXPR_LIST (VOIDmode
, fun
, note
);
4109 insns
= get_insns ();
4112 if (flags
& ECF_PURE
)
4113 note
= gen_rtx_EXPR_LIST (VOIDmode
,
4114 gen_rtx_USE (VOIDmode
,
4115 gen_rtx_MEM (BLKmode
,
4116 gen_rtx_SCRATCH (VOIDmode
))),
4119 emit_libcall_block (insns
, temp
, valreg
, note
);
4126 /* Copy the value to the right place. */
4127 if (outmode
!= VOIDmode
&& retval
)
4133 if (value
!= mem_value
)
4134 emit_move_insn (value
, mem_value
);
4136 else if (value
!= 0)
4137 emit_move_insn (value
, hard_libcall_value (outmode
));
4139 value
= hard_libcall_value (outmode
);
4142 if (ACCUMULATE_OUTGOING_ARGS
)
4144 #ifdef REG_PARM_STACK_SPACE
4147 enum machine_mode save_mode
= GET_MODE (save_area
);
4148 #ifdef ARGS_GROW_DOWNWARD
4150 = gen_rtx_MEM (save_mode
,
4151 memory_address (save_mode
,
4152 plus_constant (argblock
,
4156 = gen_rtx_MEM (save_mode
,
4157 memory_address (save_mode
,
4158 plus_constant (argblock
, low_to_save
)));
4161 set_mem_align (stack_area
, PARM_BOUNDARY
);
4162 if (save_mode
!= BLKmode
)
4163 emit_move_insn (stack_area
, save_area
);
4165 emit_block_move (stack_area
, validize_mem (save_area
),
4166 GEN_INT (high_to_save
- low_to_save
+ 1));
4170 /* If we saved any argument areas, restore them. */
4171 for (count
= 0; count
< nargs
; count
++)
4172 if (argvec
[count
].save_area
)
4174 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
4176 = gen_rtx_MEM (save_mode
,
4179 plus_constant (argblock
,
4180 argvec
[count
].offset
.constant
)));
4182 emit_move_insn (stack_area
, argvec
[count
].save_area
);
4185 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4186 stack_usage_map
= initial_stack_usage_map
;
4193 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4194 (emitting the queue unless NO_QUEUE is nonzero),
4195 for a value of mode OUTMODE,
4196 with NARGS different arguments, passed as alternating rtx values
4197 and machine_modes to convert them to.
4198 The rtx values should have been passed through protect_from_queue already.
4200 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4201 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4202 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4203 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4204 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4205 or other LCT_ value for other types of library calls. */
4208 emit_library_call
VPARAMS((rtx orgfun
, enum libcall_type fn_type
,
4209 enum machine_mode outmode
, int nargs
, ...))
4212 VA_FIXEDARG (p
, rtx
, orgfun
);
4213 VA_FIXEDARG (p
, int, fn_type
);
4214 VA_FIXEDARG (p
, enum machine_mode
, outmode
);
4215 VA_FIXEDARG (p
, int, nargs
);
4217 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
4222 /* Like emit_library_call except that an extra argument, VALUE,
4223 comes second and says where to store the result.
4224 (If VALUE is zero, this function chooses a convenient way
4225 to return the value.
4227 This function returns an rtx for where the value is to be found.
4228 If VALUE is nonzero, VALUE is returned. */
4231 emit_library_call_value
VPARAMS((rtx orgfun
, rtx value
,
4232 enum libcall_type fn_type
,
4233 enum machine_mode outmode
, int nargs
, ...))
4238 VA_FIXEDARG (p
, rtx
, orgfun
);
4239 VA_FIXEDARG (p
, rtx
, value
);
4240 VA_FIXEDARG (p
, int, fn_type
);
4241 VA_FIXEDARG (p
, enum machine_mode
, outmode
);
4242 VA_FIXEDARG (p
, int, nargs
);
4244 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
4252 /* Store a single argument for a function call
4253 into the register or memory area where it must be passed.
4254 *ARG describes the argument value and where to pass it.
4256 ARGBLOCK is the address of the stack-block for all the arguments,
4257 or 0 on a machine where arguments are pushed individually.
4259 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4260 so must be careful about how the stack is used.
4262 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4263 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4264 that we need not worry about saving and restoring the stack.
4266 FNDECL is the declaration of the function we are calling.
4268 Return non-zero if this arg should cause sibcall failure,
4272 store_one_arg (arg
, argblock
, flags
, variable_size
, reg_parm_stack_space
)
4273 struct arg_data
*arg
;
4276 int variable_size ATTRIBUTE_UNUSED
;
4277 int reg_parm_stack_space
;
4279 tree pval
= arg
->tree_value
;
4283 int i
, lower_bound
= 0, upper_bound
= 0;
4284 int sibcall_failure
= 0;
4286 if (TREE_CODE (pval
) == ERROR_MARK
)
4289 /* Push a new temporary level for any temporaries we make for
4293 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4295 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4296 save any previous data at that location. */
4297 if (argblock
&& ! variable_size
&& arg
->stack
)
4299 #ifdef ARGS_GROW_DOWNWARD
4300 /* stack_slot is negative, but we want to index stack_usage_map
4301 with positive values. */
4302 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4303 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4307 lower_bound
= upper_bound
- arg
->size
.constant
;
4309 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4310 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4314 upper_bound
= lower_bound
+ arg
->size
.constant
;
4317 for (i
= lower_bound
; i
< upper_bound
; i
++)
4318 if (stack_usage_map
[i
]
4319 /* Don't store things in the fixed argument area at this point;
4320 it has already been saved. */
4321 && i
> reg_parm_stack_space
)
4324 if (i
!= upper_bound
)
4326 /* We need to make a save area. See what mode we can make it. */
4327 enum machine_mode save_mode
4328 = mode_for_size (arg
->size
.constant
* BITS_PER_UNIT
, MODE_INT
, 1);
4330 = gen_rtx_MEM (save_mode
,
4331 memory_address (save_mode
,
4332 XEXP (arg
->stack_slot
, 0)));
4334 if (save_mode
== BLKmode
)
4336 tree ot
= TREE_TYPE (arg
->tree_value
);
4337 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4338 | TYPE_QUAL_CONST
));
4340 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4341 preserve_temp_slots (arg
->save_area
);
4342 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4343 expr_size (arg
->tree_value
));
4347 arg
->save_area
= gen_reg_rtx (save_mode
);
4348 emit_move_insn (arg
->save_area
, stack_area
);
4352 /* Now that we have saved any slots that will be overwritten by this
4353 store, mark all slots this store will use. We must do this before
4354 we actually expand the argument since the expansion itself may
4355 trigger library calls which might need to use the same stack slot. */
4356 if (argblock
&& ! variable_size
&& arg
->stack
)
4357 for (i
= lower_bound
; i
< upper_bound
; i
++)
4358 stack_usage_map
[i
] = 1;
4361 /* If this isn't going to be placed on both the stack and in registers,
4362 set up the register and number of words. */
4363 if (! arg
->pass_on_stack
)
4364 reg
= arg
->reg
, partial
= arg
->partial
;
4366 if (reg
!= 0 && partial
== 0)
4367 /* Being passed entirely in a register. We shouldn't be called in
4371 /* If this arg needs special alignment, don't load the registers
4373 if (arg
->n_aligned_regs
!= 0)
4376 /* If this is being passed partially in a register, we can't evaluate
4377 it directly into its stack slot. Otherwise, we can. */
4378 if (arg
->value
== 0)
4380 /* stack_arg_under_construction is nonzero if a function argument is
4381 being evaluated directly into the outgoing argument list and
4382 expand_call must take special action to preserve the argument list
4383 if it is called recursively.
4385 For scalar function arguments stack_usage_map is sufficient to
4386 determine which stack slots must be saved and restored. Scalar
4387 arguments in general have pass_on_stack == 0.
4389 If this argument is initialized by a function which takes the
4390 address of the argument (a C++ constructor or a C function
4391 returning a BLKmode structure), then stack_usage_map is
4392 insufficient and expand_call must push the stack around the
4393 function call. Such arguments have pass_on_stack == 1.
4395 Note that it is always safe to set stack_arg_under_construction,
4396 but this generates suboptimal code if set when not needed. */
4398 if (arg
->pass_on_stack
)
4399 stack_arg_under_construction
++;
4401 arg
->value
= expand_expr (pval
,
4403 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4404 ? NULL_RTX
: arg
->stack
,
4407 /* If we are promoting object (or for any other reason) the mode
4408 doesn't agree, convert the mode. */
4410 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4411 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4412 arg
->value
, arg
->unsignedp
);
4414 if (arg
->pass_on_stack
)
4415 stack_arg_under_construction
--;
4418 /* Don't allow anything left on stack from computation
4419 of argument to alloca. */
4420 if (flags
& ECF_MAY_BE_ALLOCA
)
4421 do_pending_stack_adjust ();
4423 if (arg
->value
== arg
->stack
)
4424 /* If the value is already in the stack slot, we are done. */
4426 else if (arg
->mode
!= BLKmode
)
4430 /* Argument is a scalar, not entirely passed in registers.
4431 (If part is passed in registers, arg->partial says how much
4432 and emit_push_insn will take care of putting it there.)
4434 Push it, and if its size is less than the
4435 amount of space allocated to it,
4436 also bump stack pointer by the additional space.
4437 Note that in C the default argument promotions
4438 will prevent such mismatches. */
4440 size
= GET_MODE_SIZE (arg
->mode
);
4441 /* Compute how much space the push instruction will push.
4442 On many machines, pushing a byte will advance the stack
4443 pointer by a halfword. */
4444 #ifdef PUSH_ROUNDING
4445 size
= PUSH_ROUNDING (size
);
4449 /* Compute how much space the argument should get:
4450 round up to a multiple of the alignment for arguments. */
4451 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4452 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4453 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4454 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4456 /* This isn't already where we want it on the stack, so put it there.
4457 This can either be done with push or copy insns. */
4458 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
, 0,
4459 partial
, reg
, used
- size
, argblock
,
4460 ARGS_SIZE_RTX (arg
->offset
), reg_parm_stack_space
,
4461 ARGS_SIZE_RTX (arg
->alignment_pad
));
4465 /* BLKmode, at least partly to be pushed. */
4470 /* Pushing a nonscalar.
4471 If part is passed in registers, PARTIAL says how much
4472 and emit_push_insn will take care of putting it there. */
4474 /* Round its size up to a multiple
4475 of the allocation unit for arguments. */
4477 if (arg
->size
.var
!= 0)
4480 size_rtx
= ARGS_SIZE_RTX (arg
->size
);
4484 /* PUSH_ROUNDING has no effect on us, because
4485 emit_push_insn for BLKmode is careful to avoid it. */
4486 excess
= (arg
->size
.constant
- int_size_in_bytes (TREE_TYPE (pval
))
4487 + partial
* UNITS_PER_WORD
);
4488 size_rtx
= expr_size (pval
);
4491 if ((flags
& ECF_SIBCALL
) && GET_CODE (arg
->value
) == MEM
)
4493 /* emit_push_insn might not work properly if arg->value and
4494 argblock + arg->offset areas overlap. */
4498 if (XEXP (x
, 0) == current_function_internal_arg_pointer
4499 || (GET_CODE (XEXP (x
, 0)) == PLUS
4500 && XEXP (XEXP (x
, 0), 0) ==
4501 current_function_internal_arg_pointer
4502 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
))
4504 if (XEXP (x
, 0) != current_function_internal_arg_pointer
)
4505 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4507 /* expand_call should ensure this */
4508 if (arg
->offset
.var
|| GET_CODE (size_rtx
) != CONST_INT
)
4511 if (arg
->offset
.constant
> i
)
4513 if (arg
->offset
.constant
< i
+ INTVAL (size_rtx
))
4514 sibcall_failure
= 1;
4516 else if (arg
->offset
.constant
< i
)
4518 if (i
< arg
->offset
.constant
+ INTVAL (size_rtx
))
4519 sibcall_failure
= 1;
4524 /* Special handling is required if part of the parameter lies in the
4525 register parameter area. The argument may be copied into the stack
4526 slot using memcpy(), but the original contents of the register
4527 parameter area will be restored after the memcpy() call.
4529 To ensure that the part that lies in the register parameter area
4530 is copied correctly, we emit a separate push for that part. This
4531 push should be small enough to avoid a call to memcpy(). */
4532 #ifndef STACK_PARMS_IN_REG_PARM_AREA
4533 if (arg
->reg
&& arg
->pass_on_stack
)
4538 if (arg
->offset
.constant
< reg_parm_stack_space
&& arg
->offset
.var
)
4539 error ("variable offset is passed partially in stack and in reg");
4540 else if (arg
->offset
.constant
< reg_parm_stack_space
&& arg
->size
.var
)
4541 error ("variable size is passed partially in stack and in reg");
4542 else if (arg
->offset
.constant
< reg_parm_stack_space
4543 && ((arg
->offset
.constant
+ arg
->size
.constant
)
4544 > reg_parm_stack_space
))
4546 rtx size_rtx1
= GEN_INT (reg_parm_stack_space
- arg
->offset
.constant
);
4547 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx1
,
4548 TYPE_ALIGN (TREE_TYPE (pval
)), partial
, reg
,
4549 excess
, argblock
, ARGS_SIZE_RTX (arg
->offset
),
4550 reg_parm_stack_space
,
4551 ARGS_SIZE_RTX (arg
->alignment_pad
));
4556 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4557 TYPE_ALIGN (TREE_TYPE (pval
)), partial
, reg
, excess
,
4558 argblock
, ARGS_SIZE_RTX (arg
->offset
),
4559 reg_parm_stack_space
,
4560 ARGS_SIZE_RTX (arg
->alignment_pad
));
4563 /* Unless this is a partially-in-register argument, the argument is now
4566 ??? Note that this can change arg->value from arg->stack to
4567 arg->stack_slot and it matters when they are not the same.
4568 It isn't totally clear that this is correct in all cases. */
4570 arg
->value
= arg
->stack_slot
;
4572 /* Once we have pushed something, pops can't safely
4573 be deferred during the rest of the arguments. */
4576 /* ANSI doesn't require a sequence point here,
4577 but PCC has one, so this will avoid some problems. */
4580 /* Free any temporary slots made in processing this argument. Show
4581 that we might have taken the address of something and pushed that
4583 preserve_temp_slots (NULL_RTX
);
4587 return sibcall_failure
;