1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998
3 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
24 #include "coretypes.h"
38 #include "langhooks.h"
42 /* Decide whether a function's arguments should be processed
43 from first to last or from last to first.
45 They should if the stack and args grow in opposite directions, but
46 only if we have push insns. */
50 #ifndef PUSH_ARGS_REVERSED
51 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
52 #define PUSH_ARGS_REVERSED PUSH_ARGS
58 #ifndef PUSH_ARGS_REVERSED
59 #define PUSH_ARGS_REVERSED 0
62 #ifndef STACK_POINTER_OFFSET
63 #define STACK_POINTER_OFFSET 0
66 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
67 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
69 /* Data structure and subroutines used within expand_call. */
73 /* Tree node for this argument. */
75 /* Mode for value; TYPE_MODE unless promoted. */
76 enum machine_mode mode
;
77 /* Current RTL value for argument, or 0 if it isn't precomputed. */
79 /* Initially-compute RTL value for argument; only for const functions. */
81 /* Register to pass this argument in, 0 if passed on stack, or an
82 PARALLEL if the arg is to be copied into multiple non-contiguous
85 /* Register to pass this argument in when generating tail call sequence.
86 This is not the same register as for normal calls on machines with
89 /* If REG was promoted from the actual mode of the argument expression,
90 indicates whether the promotion is sign- or zero-extended. */
92 /* Number of registers to use. 0 means put the whole arg in registers.
93 Also 0 if not passed in registers. */
95 /* Nonzero if argument must be passed on stack.
96 Note that some arguments may be passed on the stack
97 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
98 pass_on_stack identifies arguments that *cannot* go in registers. */
100 /* Offset of this argument from beginning of stack-args. */
101 struct args_size offset
;
102 /* Similar, but offset to the start of the stack slot. Different from
103 OFFSET if this arg pads downward. */
104 struct args_size slot_offset
;
105 /* Size of this argument on the stack, rounded up for any padding it gets,
106 parts of the argument passed in registers do not count.
107 If REG_PARM_STACK_SPACE is defined, then register parms
108 are counted here as well. */
109 struct args_size size
;
110 /* Location on the stack at which parameter should be stored. The store
111 has already been done if STACK == VALUE. */
113 /* Location on the stack of the start of this argument slot. This can
114 differ from STACK if this arg pads downward. This location is known
115 to be aligned to FUNCTION_ARG_BOUNDARY. */
117 /* Place that this stack area has been saved, if needed. */
119 /* If an argument's alignment does not permit direct copying into registers,
120 copy in smaller-sized pieces into pseudos. These are stored in a
121 block pointed to by this field. The next field says how many
122 word-sized pseudos we made. */
125 /* The amount that the stack pointer needs to be adjusted to
126 force alignment for the next argument. */
127 struct args_size alignment_pad
;
130 /* A vector of one char per byte of stack space. A byte if nonzero if
131 the corresponding stack location has been used.
132 This vector is used to prevent a function call within an argument from
133 clobbering any stack already set up. */
134 static char *stack_usage_map
;
136 /* Size of STACK_USAGE_MAP. */
137 static int highest_outgoing_arg_in_use
;
139 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
140 stack location's tail call argument has been already stored into the stack.
141 This bitmap is used to prevent sibling call optimization if function tries
142 to use parent's incoming argument slots when they have been already
143 overwritten with tail call arguments. */
144 static sbitmap stored_args_map
;
146 /* stack_arg_under_construction is nonzero when an argument may be
147 initialized with a constructor call (including a C function that
148 returns a BLKmode struct) and expand_call must take special action
149 to make sure the object being constructed does not overlap the
150 argument list for the constructor call. */
151 int stack_arg_under_construction
;
153 static int calls_function
PARAMS ((tree
, int));
154 static int calls_function_1
PARAMS ((tree
, int));
156 static void emit_call_1
PARAMS ((rtx
, tree
, tree
, HOST_WIDE_INT
,
157 HOST_WIDE_INT
, HOST_WIDE_INT
, rtx
,
160 static void precompute_register_parameters
PARAMS ((int,
163 static int store_one_arg
PARAMS ((struct arg_data
*, rtx
, int, int,
165 static void store_unaligned_arguments_into_pseudos
PARAMS ((struct arg_data
*,
167 static int finalize_must_preallocate
PARAMS ((int, int,
169 struct args_size
*));
170 static void precompute_arguments
PARAMS ((int, int,
172 static int compute_argument_block_size
PARAMS ((int,
175 static void initialize_argument_information
PARAMS ((int,
182 static void compute_argument_addresses
PARAMS ((struct arg_data
*,
184 static rtx rtx_for_function_call
PARAMS ((tree
, tree
));
185 static void load_register_parameters
PARAMS ((struct arg_data
*,
188 static rtx emit_library_call_value_1
PARAMS ((int, rtx
, rtx
,
192 static int special_function_p
PARAMS ((tree
, int));
193 static rtx try_to_integrate
PARAMS ((tree
, tree
, rtx
,
195 static int check_sibcall_argument_overlap_1
PARAMS ((rtx
));
196 static int check_sibcall_argument_overlap
PARAMS ((rtx
, struct arg_data
*,
199 static int combine_pending_stack_adjustment_and_call
200 PARAMS ((int, struct args_size
*, int));
201 static tree fix_unsafe_tree
PARAMS ((tree
));
203 #ifdef REG_PARM_STACK_SPACE
204 static rtx save_fixed_argument_area
PARAMS ((int, rtx
, int *, int *));
205 static void restore_fixed_argument_area
PARAMS ((rtx
, rtx
, int, int));
208 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
211 If WHICH is 0, return 1 if EXP contains a call to any function.
212 Actually, we only need return 1 if evaluating EXP would require pushing
213 arguments on the stack, but that is too difficult to compute, so we just
214 assume any function call might require the stack. */
216 static tree calls_function_save_exprs
;
219 calls_function (exp
, which
)
225 calls_function_save_exprs
= 0;
226 val
= calls_function_1 (exp
, which
);
227 calls_function_save_exprs
= 0;
231 /* Recursive function to do the work of above function. */
234 calls_function_1 (exp
, which
)
239 enum tree_code code
= TREE_CODE (exp
);
240 int class = TREE_CODE_CLASS (code
);
241 int length
= first_rtl_op (code
);
243 /* If this code is language-specific, we don't know what it will do. */
244 if ((int) code
>= NUM_TREE_CODES
)
252 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp
, 0))))
254 && (TYPE_RETURNS_STACK_DEPRESSED
255 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp
, 0))))))
257 else if (TREE_CODE (TREE_OPERAND (exp
, 0)) == ADDR_EXPR
258 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0))
260 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0),
262 & ECF_MAY_BE_ALLOCA
))
271 for (tem
= CONSTRUCTOR_ELTS (exp
); tem
!= 0; tem
= TREE_CHAIN (tem
))
272 if (calls_function_1 (TREE_VALUE (tem
), which
))
279 if (SAVE_EXPR_RTL (exp
) != 0)
281 if (value_member (exp
, calls_function_save_exprs
))
283 calls_function_save_exprs
= tree_cons (NULL_TREE
, exp
,
284 calls_function_save_exprs
);
285 return (TREE_OPERAND (exp
, 0) != 0
286 && calls_function_1 (TREE_OPERAND (exp
, 0), which
));
293 for (local
= BLOCK_VARS (exp
); local
; local
= TREE_CHAIN (local
))
294 if (DECL_INITIAL (local
) != 0
295 && calls_function_1 (DECL_INITIAL (local
), which
))
298 for (subblock
= BLOCK_SUBBLOCKS (exp
);
300 subblock
= TREE_CHAIN (subblock
))
301 if (calls_function_1 (subblock
, which
))
307 for (; exp
!= 0; exp
= TREE_CHAIN (exp
))
308 if (calls_function_1 (TREE_VALUE (exp
), which
))
316 /* Only expressions, references, and blocks can contain calls. */
317 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
320 for (i
= 0; i
< length
; i
++)
321 if (TREE_OPERAND (exp
, i
) != 0
322 && calls_function_1 (TREE_OPERAND (exp
, i
), which
))
328 /* Force FUNEXP into a form suitable for the address of a CALL,
329 and return that as an rtx. Also load the static chain register
330 if FNDECL is a nested function.
332 CALL_FUSAGE points to a variable holding the prospective
333 CALL_INSN_FUNCTION_USAGE information. */
336 prepare_call_address (funexp
, fndecl
, call_fusage
, reg_parm_seen
, sibcallp
)
343 rtx static_chain_value
= 0;
345 funexp
= protect_from_queue (funexp
, 0);
348 /* Get possible static chain value for nested function in C. */
349 static_chain_value
= lookup_static_chain (fndecl
);
351 /* Make a valid memory address and copy constants thru pseudo-regs,
352 but not for a constant address if -fno-function-cse. */
353 if (GET_CODE (funexp
) != SYMBOL_REF
)
354 /* If we are using registers for parameters, force the
355 function address into a register now. */
356 funexp
= ((SMALL_REGISTER_CLASSES
&& reg_parm_seen
)
357 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
358 : memory_address (FUNCTION_MODE
, funexp
));
361 #ifndef NO_FUNCTION_CSE
362 if (optimize
&& ! flag_no_function_cse
)
363 #ifdef NO_RECURSIVE_FUNCTION_CSE
364 if (fndecl
!= current_function_decl
)
366 funexp
= force_reg (Pmode
, funexp
);
370 if (static_chain_value
!= 0)
372 emit_move_insn (static_chain_rtx
, static_chain_value
);
374 if (GET_CODE (static_chain_rtx
) == REG
)
375 use_reg (call_fusage
, static_chain_rtx
);
381 /* Generate instructions to call function FUNEXP,
382 and optionally pop the results.
383 The CALL_INSN is the first insn generated.
385 FNDECL is the declaration node of the function. This is given to the
386 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
388 FUNTYPE is the data type of the function. This is given to the macro
389 RETURN_POPS_ARGS to determine whether this function pops its own args.
390 We used to allow an identifier for library functions, but that doesn't
391 work when the return type is an aggregate type and the calling convention
392 says that the pointer to this aggregate is to be popped by the callee.
394 STACK_SIZE is the number of bytes of arguments on the stack,
395 ROUNDED_STACK_SIZE is that number rounded up to
396 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
397 both to put into the call insn and to generate explicit popping
400 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
401 It is zero if this call doesn't want a structure value.
403 NEXT_ARG_REG is the rtx that results from executing
404 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
405 just after all the args have had their registers assigned.
406 This could be whatever you like, but normally it is the first
407 arg-register beyond those used for args in this call,
408 or 0 if all the arg-registers are used in this call.
409 It is passed on to `gen_call' so you can put this info in the call insn.
411 VALREG is a hard register in which a value is returned,
412 or 0 if the call does not return a value.
414 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
415 the args to this call were processed.
416 We restore `inhibit_defer_pop' to that value.
418 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
419 denote registers used by the called function. */
422 emit_call_1 (funexp
, fndecl
, funtype
, stack_size
, rounded_stack_size
,
423 struct_value_size
, next_arg_reg
, valreg
, old_inhibit_defer_pop
,
424 call_fusage
, ecf_flags
, args_so_far
)
426 tree fndecl ATTRIBUTE_UNUSED
;
427 tree funtype ATTRIBUTE_UNUSED
;
428 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED
;
429 HOST_WIDE_INT rounded_stack_size
;
430 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED
;
431 rtx next_arg_reg ATTRIBUTE_UNUSED
;
433 int old_inhibit_defer_pop
;
436 CUMULATIVE_ARGS
*args_so_far ATTRIBUTE_UNUSED
;
438 rtx rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
440 int already_popped
= 0;
441 HOST_WIDE_INT n_popped
= RETURN_POPS_ARGS (fndecl
, funtype
, stack_size
);
442 #if defined (HAVE_call) && defined (HAVE_call_value)
443 rtx struct_value_size_rtx
;
444 struct_value_size_rtx
= GEN_INT (struct_value_size
);
447 #ifdef CALL_POPS_ARGS
448 n_popped
+= CALL_POPS_ARGS (* args_so_far
);
451 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
452 and we don't want to load it into a register as an optimization,
453 because prepare_call_address already did it if it should be done. */
454 if (GET_CODE (funexp
) != SYMBOL_REF
)
455 funexp
= memory_address (FUNCTION_MODE
, funexp
);
457 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
458 if ((ecf_flags
& ECF_SIBCALL
)
459 && HAVE_sibcall_pop
&& HAVE_sibcall_value_pop
460 && (n_popped
> 0 || stack_size
== 0))
462 rtx n_pop
= GEN_INT (n_popped
);
465 /* If this subroutine pops its own args, record that in the call insn
466 if possible, for the sake of frame pointer elimination. */
469 pat
= GEN_SIBCALL_VALUE_POP (valreg
,
470 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
471 rounded_stack_size_rtx
, next_arg_reg
,
474 pat
= GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
475 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
477 emit_call_insn (pat
);
483 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
484 /* If the target has "call" or "call_value" insns, then prefer them
485 if no arguments are actually popped. If the target does not have
486 "call" or "call_value" insns, then we must use the popping versions
487 even if the call has no arguments to pop. */
488 #if defined (HAVE_call) && defined (HAVE_call_value)
489 if (HAVE_call
&& HAVE_call_value
&& HAVE_call_pop
&& HAVE_call_value_pop
490 && n_popped
> 0 && ! (ecf_flags
& ECF_SP_DEPRESSED
))
492 if (HAVE_call_pop
&& HAVE_call_value_pop
)
495 rtx n_pop
= GEN_INT (n_popped
);
498 /* If this subroutine pops its own args, record that in the call insn
499 if possible, for the sake of frame pointer elimination. */
502 pat
= GEN_CALL_VALUE_POP (valreg
,
503 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
504 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
506 pat
= GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
507 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
509 emit_call_insn (pat
);
515 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
516 if ((ecf_flags
& ECF_SIBCALL
)
517 && HAVE_sibcall
&& HAVE_sibcall_value
)
520 emit_call_insn (GEN_SIBCALL_VALUE (valreg
,
521 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
522 rounded_stack_size_rtx
,
523 next_arg_reg
, NULL_RTX
));
525 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
526 rounded_stack_size_rtx
, next_arg_reg
,
527 struct_value_size_rtx
));
532 #if defined (HAVE_call) && defined (HAVE_call_value)
533 if (HAVE_call
&& HAVE_call_value
)
536 emit_call_insn (GEN_CALL_VALUE (valreg
,
537 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
538 rounded_stack_size_rtx
, next_arg_reg
,
541 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
542 rounded_stack_size_rtx
, next_arg_reg
,
543 struct_value_size_rtx
));
549 /* Find the CALL insn we just emitted. */
550 for (call_insn
= get_last_insn ();
551 call_insn
&& GET_CODE (call_insn
) != CALL_INSN
;
552 call_insn
= PREV_INSN (call_insn
))
558 /* Mark memory as used for "pure" function call. */
559 if (ecf_flags
& ECF_PURE
)
563 gen_rtx_USE (VOIDmode
,
564 gen_rtx_MEM (BLKmode
, gen_rtx_SCRATCH (VOIDmode
))),
567 /* Put the register usage information on the CALL. If there is already
568 some usage information, put ours at the end. */
569 if (CALL_INSN_FUNCTION_USAGE (call_insn
))
573 for (link
= CALL_INSN_FUNCTION_USAGE (call_insn
); XEXP (link
, 1) != 0;
574 link
= XEXP (link
, 1))
577 XEXP (link
, 1) = call_fusage
;
580 CALL_INSN_FUNCTION_USAGE (call_insn
) = call_fusage
;
582 /* If this is a const call, then set the insn's unchanging bit. */
583 if (ecf_flags
& (ECF_CONST
| ECF_PURE
))
584 CONST_OR_PURE_CALL_P (call_insn
) = 1;
586 /* If this call can't throw, attach a REG_EH_REGION reg note to that
588 if (ecf_flags
& ECF_NOTHROW
)
589 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_EH_REGION
, const0_rtx
,
590 REG_NOTES (call_insn
));
592 if (ecf_flags
& ECF_NORETURN
)
593 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_NORETURN
, const0_rtx
,
594 REG_NOTES (call_insn
));
595 if (ecf_flags
& ECF_ALWAYS_RETURN
)
596 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN
, const0_rtx
,
597 REG_NOTES (call_insn
));
599 if (ecf_flags
& ECF_RETURNS_TWICE
)
601 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_SETJMP
, const0_rtx
,
602 REG_NOTES (call_insn
));
603 current_function_calls_setjmp
= 1;
606 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
608 /* Restore this now, so that we do defer pops for this call's args
609 if the context of the call as a whole permits. */
610 inhibit_defer_pop
= old_inhibit_defer_pop
;
615 CALL_INSN_FUNCTION_USAGE (call_insn
)
616 = gen_rtx_EXPR_LIST (VOIDmode
,
617 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
618 CALL_INSN_FUNCTION_USAGE (call_insn
));
619 rounded_stack_size
-= n_popped
;
620 rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
621 stack_pointer_delta
-= n_popped
;
624 if (!ACCUMULATE_OUTGOING_ARGS
)
626 /* If returning from the subroutine does not automatically pop the args,
627 we need an instruction to pop them sooner or later.
628 Perhaps do it now; perhaps just record how much space to pop later.
630 If returning from the subroutine does pop the args, indicate that the
631 stack pointer will be changed. */
633 if (rounded_stack_size
!= 0)
635 if (ecf_flags
& ECF_SP_DEPRESSED
)
636 /* Just pretend we did the pop. */
637 stack_pointer_delta
-= rounded_stack_size
;
638 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
639 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
640 pending_stack_adjust
+= rounded_stack_size
;
642 adjust_stack (rounded_stack_size_rtx
);
645 /* When we accumulate outgoing args, we must avoid any stack manipulations.
646 Restore the stack pointer to its original value now. Usually
647 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
648 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
649 popping variants of functions exist as well.
651 ??? We may optimize similar to defer_pop above, but it is
652 probably not worthwhile.
654 ??? It will be worthwhile to enable combine_stack_adjustments even for
657 anti_adjust_stack (GEN_INT (n_popped
));
660 /* Determine if the function identified by NAME and FNDECL is one with
661 special properties we wish to know about.
663 For example, if the function might return more than one time (setjmp), then
664 set RETURNS_TWICE to a nonzero value.
666 Similarly set LONGJMP for if the function is in the longjmp family.
668 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
669 space from the stack such as alloca. */
672 special_function_p (fndecl
, flags
)
676 if (! (flags
& ECF_MALLOC
)
677 && fndecl
&& DECL_NAME (fndecl
)
678 && IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) <= 17
679 /* Exclude functions not at the file scope, or not `extern',
680 since they are not the magic functions we would otherwise
682 && DECL_CONTEXT (fndecl
) == NULL_TREE
&& TREE_PUBLIC (fndecl
))
684 const char *name
= IDENTIFIER_POINTER (DECL_NAME (fndecl
));
685 const char *tname
= name
;
687 /* We assume that alloca will always be called by name. It
688 makes no sense to pass it as a pointer-to-function to
689 anything that does not understand its behavior. */
690 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 6
692 && ! strcmp (name
, "alloca"))
693 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 16
695 && ! strcmp (name
, "__builtin_alloca"))))
696 flags
|= ECF_MAY_BE_ALLOCA
;
698 /* Disregard prefix _, __ or __x. */
701 if (name
[1] == '_' && name
[2] == 'x')
703 else if (name
[1] == '_')
712 && (! strcmp (tname
, "setjmp")
713 || ! strcmp (tname
, "setjmp_syscall")))
715 && ! strcmp (tname
, "sigsetjmp"))
717 && ! strcmp (tname
, "savectx")))
718 flags
|= ECF_RETURNS_TWICE
;
721 && ! strcmp (tname
, "siglongjmp"))
722 flags
|= ECF_LONGJMP
;
724 else if ((tname
[0] == 'q' && tname
[1] == 's'
725 && ! strcmp (tname
, "qsetjmp"))
726 || (tname
[0] == 'v' && tname
[1] == 'f'
727 && ! strcmp (tname
, "vfork")))
728 flags
|= ECF_RETURNS_TWICE
;
730 else if (tname
[0] == 'l' && tname
[1] == 'o'
731 && ! strcmp (tname
, "longjmp"))
732 flags
|= ECF_LONGJMP
;
734 else if ((tname
[0] == 'f' && tname
[1] == 'o'
735 && ! strcmp (tname
, "fork"))
736 /* Linux specific: __clone. check NAME to insist on the
737 leading underscores, to avoid polluting the ISO / POSIX
739 || (name
[0] == '_' && name
[1] == '_'
740 && ! strcmp (tname
, "clone"))
741 || (tname
[0] == 'e' && tname
[1] == 'x' && tname
[2] == 'e'
742 && tname
[3] == 'c' && (tname
[4] == 'l' || tname
[4] == 'v')
744 || ((tname
[5] == 'p' || tname
[5] == 'e')
745 && tname
[6] == '\0'))))
746 flags
|= ECF_FORK_OR_EXEC
;
751 /* Return nonzero when tree represent call to longjmp. */
754 setjmp_call_p (fndecl
)
757 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
760 /* Return true when exp contains alloca call. */
765 if (TREE_CODE (exp
) == CALL_EXPR
766 && TREE_CODE (TREE_OPERAND (exp
, 0)) == ADDR_EXPR
767 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0))
769 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0),
770 0) & ECF_MAY_BE_ALLOCA
))
775 /* Detect flags (function attributes) from the function decl or type node. */
778 flags_from_decl_or_type (exp
)
786 struct cgraph_rtl_info
*i
= cgraph_rtl_info (exp
);
787 type
= TREE_TYPE (exp
);
791 if (i
->pure_function
)
792 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
793 if (i
->const_function
)
794 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
797 /* The function exp may have the `malloc' attribute. */
798 if (DECL_IS_MALLOC (exp
))
801 /* The function exp may have the `pure' attribute. */
802 if (DECL_IS_PURE (exp
))
803 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
805 if (TREE_NOTHROW (exp
))
806 flags
|= ECF_NOTHROW
;
809 if (TREE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
810 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
812 if (TREE_THIS_VOLATILE (exp
))
813 flags
|= ECF_NORETURN
;
815 /* Mark if the function returns with the stack pointer depressed. We
816 cannot consider it pure or constant in that case. */
817 if (TREE_CODE (type
) == FUNCTION_TYPE
&& TYPE_RETURNS_STACK_DEPRESSED (type
))
819 flags
|= ECF_SP_DEPRESSED
;
820 flags
&= ~(ECF_PURE
| ECF_CONST
| ECF_LIBCALL_BLOCK
);
826 /* Precompute all register parameters as described by ARGS, storing values
827 into fields within the ARGS array.
829 NUM_ACTUALS indicates the total number elements in the ARGS array.
831 Set REG_PARM_SEEN if we encounter a register parameter. */
834 precompute_register_parameters (num_actuals
, args
, reg_parm_seen
)
836 struct arg_data
*args
;
843 for (i
= 0; i
< num_actuals
; i
++)
844 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
848 if (args
[i
].value
== 0)
851 args
[i
].value
= expand_expr (args
[i
].tree_value
, NULL_RTX
,
853 preserve_temp_slots (args
[i
].value
);
856 /* ANSI doesn't require a sequence point here,
857 but PCC has one, so this will avoid some problems. */
861 /* If the value is a non-legitimate constant, force it into a
862 pseudo now. TLS symbols sometimes need a call to resolve. */
863 if (CONSTANT_P (args
[i
].value
)
864 && !LEGITIMATE_CONSTANT_P (args
[i
].value
))
865 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
867 /* If we are to promote the function arg to a wider mode,
870 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
872 = convert_modes (args
[i
].mode
,
873 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
874 args
[i
].value
, args
[i
].unsignedp
);
876 /* If the value is expensive, and we are inside an appropriately
877 short loop, put the value into a pseudo and then put the pseudo
880 For small register classes, also do this if this call uses
881 register parameters. This is to avoid reload conflicts while
882 loading the parameters registers. */
884 if ((! (GET_CODE (args
[i
].value
) == REG
885 || (GET_CODE (args
[i
].value
) == SUBREG
886 && GET_CODE (SUBREG_REG (args
[i
].value
)) == REG
)))
887 && args
[i
].mode
!= BLKmode
888 && rtx_cost (args
[i
].value
, SET
) > COSTS_N_INSNS (1)
889 && ((SMALL_REGISTER_CLASSES
&& *reg_parm_seen
)
890 || preserve_subexpressions_p ()))
891 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
895 #ifdef REG_PARM_STACK_SPACE
897 /* The argument list is the property of the called routine and it
898 may clobber it. If the fixed area has been used for previous
899 parameters, we must save and restore it. */
902 save_fixed_argument_area (reg_parm_stack_space
, argblock
,
903 low_to_save
, high_to_save
)
904 int reg_parm_stack_space
;
912 /* Compute the boundary of the area that needs to be saved, if any. */
913 high
= reg_parm_stack_space
;
914 #ifdef ARGS_GROW_DOWNWARD
917 if (high
> highest_outgoing_arg_in_use
)
918 high
= highest_outgoing_arg_in_use
;
920 for (low
= 0; low
< high
; low
++)
921 if (stack_usage_map
[low
] != 0)
924 enum machine_mode save_mode
;
929 while (stack_usage_map
[--high
] == 0)
933 *high_to_save
= high
;
935 num_to_save
= high
- low
+ 1;
936 save_mode
= mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
938 /* If we don't have the required alignment, must do this
940 if ((low
& (MIN (GET_MODE_SIZE (save_mode
),
941 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
944 #ifdef ARGS_GROW_DOWNWARD
949 stack_area
= gen_rtx_MEM (save_mode
,
950 memory_address (save_mode
,
951 plus_constant (argblock
,
954 set_mem_align (stack_area
, PARM_BOUNDARY
);
955 if (save_mode
== BLKmode
)
957 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
958 emit_block_move (validize_mem (save_area
), stack_area
,
959 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
963 save_area
= gen_reg_rtx (save_mode
);
964 emit_move_insn (save_area
, stack_area
);
974 restore_fixed_argument_area (save_area
, argblock
, high_to_save
, low_to_save
)
980 enum machine_mode save_mode
= GET_MODE (save_area
);
984 #ifdef ARGS_GROW_DOWNWARD
985 delta
= -high_to_save
;
989 stack_area
= gen_rtx_MEM (save_mode
,
990 memory_address (save_mode
,
991 plus_constant (argblock
, delta
)));
992 set_mem_align (stack_area
, PARM_BOUNDARY
);
994 if (save_mode
!= BLKmode
)
995 emit_move_insn (stack_area
, save_area
);
997 emit_block_move (stack_area
, validize_mem (save_area
),
998 GEN_INT (high_to_save
- low_to_save
+ 1),
1001 #endif /* REG_PARM_STACK_SPACE */
1003 /* If any elements in ARGS refer to parameters that are to be passed in
1004 registers, but not in memory, and whose alignment does not permit a
1005 direct copy into registers. Copy the values into a group of pseudos
1006 which we will later copy into the appropriate hard registers.
1008 Pseudos for each unaligned argument will be stored into the array
1009 args[argnum].aligned_regs. The caller is responsible for deallocating
1010 the aligned_regs array if it is nonzero. */
1013 store_unaligned_arguments_into_pseudos (args
, num_actuals
)
1014 struct arg_data
*args
;
1019 for (i
= 0; i
< num_actuals
; i
++)
1020 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
1021 && args
[i
].mode
== BLKmode
1022 && (TYPE_ALIGN (TREE_TYPE (args
[i
].tree_value
))
1023 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
1025 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1026 int big_endian_correction
= 0;
1028 args
[i
].n_aligned_regs
1029 = args
[i
].partial
? args
[i
].partial
1030 : (bytes
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1032 args
[i
].aligned_regs
= (rtx
*) xmalloc (sizeof (rtx
)
1033 * args
[i
].n_aligned_regs
);
1035 /* Structures smaller than a word are aligned to the least
1036 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1037 this means we must skip the empty high order bytes when
1038 calculating the bit offset. */
1039 if (BYTES_BIG_ENDIAN
1040 && bytes
< UNITS_PER_WORD
)
1041 big_endian_correction
= (BITS_PER_WORD
- (bytes
* BITS_PER_UNIT
));
1043 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1045 rtx reg
= gen_reg_rtx (word_mode
);
1046 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
1047 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
1049 args
[i
].aligned_regs
[j
] = reg
;
1051 /* There is no need to restrict this code to loading items
1052 in TYPE_ALIGN sized hunks. The bitfield instructions can
1053 load up entire word sized registers efficiently.
1055 ??? This may not be needed anymore.
1056 We use to emit a clobber here but that doesn't let later
1057 passes optimize the instructions we emit. By storing 0 into
1058 the register later passes know the first AND to zero out the
1059 bitfield being set in the register is unnecessary. The store
1060 of 0 will be deleted as will at least the first AND. */
1062 emit_move_insn (reg
, const0_rtx
);
1064 bytes
-= bitsize
/ BITS_PER_UNIT
;
1065 store_bit_field (reg
, bitsize
, big_endian_correction
, word_mode
,
1066 extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
1067 word_mode
, word_mode
,
1074 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1077 NUM_ACTUALS is the total number of parameters.
1079 N_NAMED_ARGS is the total number of named arguments.
1081 FNDECL is the tree code for the target of this call (if known)
1083 ARGS_SO_FAR holds state needed by the target to know where to place
1086 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1087 for arguments which are passed in registers.
1089 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1090 and may be modified by this routine.
1092 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1093 flags which may may be modified by this routine. */
1096 initialize_argument_information (num_actuals
, args
, args_size
, n_named_args
,
1097 actparms
, fndecl
, args_so_far
,
1098 reg_parm_stack_space
, old_stack_level
,
1099 old_pending_adj
, must_preallocate
,
1101 int num_actuals ATTRIBUTE_UNUSED
;
1102 struct arg_data
*args
;
1103 struct args_size
*args_size
;
1104 int n_named_args ATTRIBUTE_UNUSED
;
1107 CUMULATIVE_ARGS
*args_so_far
;
1108 int reg_parm_stack_space
;
1109 rtx
*old_stack_level
;
1110 int *old_pending_adj
;
1111 int *must_preallocate
;
1114 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1117 /* Count arg position in order args appear. */
1120 struct args_size alignment_pad
;
1124 args_size
->constant
= 0;
1127 /* In this loop, we consider args in the order they are written.
1128 We fill up ARGS from the front or from the back if necessary
1129 so that in any case the first arg to be pushed ends up at the front. */
1131 if (PUSH_ARGS_REVERSED
)
1133 i
= num_actuals
- 1, inc
= -1;
1134 /* In this case, must reverse order of args
1135 so that we compute and push the last arg first. */
1142 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1143 for (p
= actparms
, argpos
= 0; p
; p
= TREE_CHAIN (p
), i
+= inc
, argpos
++)
1145 tree type
= TREE_TYPE (TREE_VALUE (p
));
1147 enum machine_mode mode
;
1149 args
[i
].tree_value
= TREE_VALUE (p
);
1151 /* Replace erroneous argument with constant zero. */
1152 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1153 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1155 /* If TYPE is a transparent union, pass things the way we would
1156 pass the first field of the union. We have already verified that
1157 the modes are the same. */
1158 if (TREE_CODE (type
) == UNION_TYPE
&& TYPE_TRANSPARENT_UNION (type
))
1159 type
= TREE_TYPE (TYPE_FIELDS (type
));
1161 /* Decide where to pass this arg.
1163 args[i].reg is nonzero if all or part is passed in registers.
1165 args[i].partial is nonzero if part but not all is passed in registers,
1166 and the exact value says how many words are passed in registers.
1168 args[i].pass_on_stack is nonzero if the argument must at least be
1169 computed on the stack. It may then be loaded back into registers
1170 if args[i].reg is nonzero.
1172 These decisions are driven by the FUNCTION_... macros and must agree
1173 with those made by function.c. */
1175 /* See if this argument should be passed by invisible reference. */
1176 if ((TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1177 && contains_placeholder_p (TYPE_SIZE (type
)))
1178 || TREE_ADDRESSABLE (type
)
1179 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1180 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far
, TYPE_MODE (type
),
1181 type
, argpos
< n_named_args
)
1185 /* If we're compiling a thunk, pass through invisible
1186 references instead of making a copy. */
1187 if (current_function_is_thunk
1188 #ifdef FUNCTION_ARG_CALLEE_COPIES
1189 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far
, TYPE_MODE (type
),
1190 type
, argpos
< n_named_args
)
1191 /* If it's in a register, we must make a copy of it too. */
1192 /* ??? Is this a sufficient test? Is there a better one? */
1193 && !(TREE_CODE (args
[i
].tree_value
) == VAR_DECL
1194 && REG_P (DECL_RTL (args
[i
].tree_value
)))
1195 && ! TREE_ADDRESSABLE (type
))
1199 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1200 new object from the argument. If we are passing by
1201 invisible reference, the callee will do that for us, so we
1202 can strip off the TARGET_EXPR. This is not always safe,
1203 but it is safe in the only case where this is a useful
1204 optimization; namely, when the argument is a plain object.
1205 In that case, the frontend is just asking the backend to
1206 make a bitwise copy of the argument. */
1208 if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1209 && (DECL_P (TREE_OPERAND (args
[i
].tree_value
, 1)))
1210 && ! REG_P (DECL_RTL (TREE_OPERAND (args
[i
].tree_value
, 1))))
1211 args
[i
].tree_value
= TREE_OPERAND (args
[i
].tree_value
, 1);
1213 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1214 build_pointer_type (type
),
1215 args
[i
].tree_value
);
1216 type
= build_pointer_type (type
);
1218 else if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
)
1220 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1221 We implement this by passing the address of the temporary
1222 rather than expanding it into another allocated slot. */
1223 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1224 build_pointer_type (type
),
1225 args
[i
].tree_value
);
1226 type
= build_pointer_type (type
);
1230 /* We make a copy of the object and pass the address to the
1231 function being called. */
1234 if (!COMPLETE_TYPE_P (type
)
1235 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1236 || (flag_stack_check
&& ! STACK_CHECK_BUILTIN
1237 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type
),
1238 STACK_CHECK_MAX_VAR_SIZE
))))
1240 /* This is a variable-sized object. Make space on the stack
1242 rtx size_rtx
= expr_size (TREE_VALUE (p
));
1244 if (*old_stack_level
== 0)
1246 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1247 *old_pending_adj
= pending_stack_adjust
;
1248 pending_stack_adjust
= 0;
1251 copy
= gen_rtx_MEM (BLKmode
,
1252 allocate_dynamic_stack_space
1253 (size_rtx
, NULL_RTX
, TYPE_ALIGN (type
)));
1254 set_mem_attributes (copy
, type
, 1);
1257 copy
= assign_temp (type
, 0, 1, 0);
1259 store_expr (args
[i
].tree_value
, copy
, 0);
1260 *ecf_flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
1262 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1263 build_pointer_type (type
),
1264 make_tree (type
, copy
));
1265 type
= build_pointer_type (type
);
1269 mode
= TYPE_MODE (type
);
1270 unsignedp
= TREE_UNSIGNED (type
);
1272 #ifdef PROMOTE_FUNCTION_ARGS
1273 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
1276 args
[i
].unsignedp
= unsignedp
;
1277 args
[i
].mode
= mode
;
1279 args
[i
].reg
= FUNCTION_ARG (*args_so_far
, mode
, type
,
1280 argpos
< n_named_args
);
1281 #ifdef FUNCTION_INCOMING_ARG
1282 /* If this is a sibling call and the machine has register windows, the
1283 register window has to be unwinded before calling the routine, so
1284 arguments have to go into the incoming registers. */
1285 args
[i
].tail_call_reg
= FUNCTION_INCOMING_ARG (*args_so_far
, mode
, type
,
1286 argpos
< n_named_args
);
1288 args
[i
].tail_call_reg
= args
[i
].reg
;
1291 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1294 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far
, mode
, type
,
1295 argpos
< n_named_args
);
1298 args
[i
].pass_on_stack
= MUST_PASS_IN_STACK (mode
, type
);
1300 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1301 it means that we are to pass this arg in the register(s) designated
1302 by the PARALLEL, but also to pass it in the stack. */
1303 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1304 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1305 args
[i
].pass_on_stack
= 1;
1307 /* If this is an addressable type, we must preallocate the stack
1308 since we must evaluate the object into its final location.
1310 If this is to be passed in both registers and the stack, it is simpler
1312 if (TREE_ADDRESSABLE (type
)
1313 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1314 *must_preallocate
= 1;
1316 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1317 we cannot consider this function call constant. */
1318 if (TREE_ADDRESSABLE (type
))
1319 *ecf_flags
&= ~ECF_LIBCALL_BLOCK
;
1321 /* Compute the stack-size of this argument. */
1322 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1323 || reg_parm_stack_space
> 0
1324 || args
[i
].pass_on_stack
)
1325 locate_and_pad_parm (mode
, type
,
1326 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1331 fndecl
, args_size
, &args
[i
].offset
,
1332 &args
[i
].size
, &alignment_pad
);
1334 #ifndef ARGS_GROW_DOWNWARD
1335 args
[i
].slot_offset
= *args_size
;
1338 args
[i
].alignment_pad
= alignment_pad
;
1340 /* If a part of the arg was put into registers,
1341 don't include that part in the amount pushed. */
1342 if (reg_parm_stack_space
== 0 && ! args
[i
].pass_on_stack
)
1343 args
[i
].size
.constant
-= ((args
[i
].partial
* UNITS_PER_WORD
)
1344 / (PARM_BOUNDARY
/ BITS_PER_UNIT
)
1345 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
1347 /* Update ARGS_SIZE, the total stack space for args so far. */
1349 args_size
->constant
+= args
[i
].size
.constant
;
1350 if (args
[i
].size
.var
)
1352 ADD_PARM_SIZE (*args_size
, args
[i
].size
.var
);
1355 /* Since the slot offset points to the bottom of the slot,
1356 we must record it after incrementing if the args grow down. */
1357 #ifdef ARGS_GROW_DOWNWARD
1358 args
[i
].slot_offset
= *args_size
;
1360 args
[i
].slot_offset
.constant
= -args_size
->constant
;
1362 SUB_PARM_SIZE (args
[i
].slot_offset
, args_size
->var
);
1365 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1366 have been used, etc. */
1368 FUNCTION_ARG_ADVANCE (*args_so_far
, TYPE_MODE (type
), type
,
1369 argpos
< n_named_args
);
1373 /* Update ARGS_SIZE to contain the total size for the argument block.
1374 Return the original constant component of the argument block's size.
1376 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1377 for arguments passed in registers. */
1380 compute_argument_block_size (reg_parm_stack_space
, args_size
,
1381 preferred_stack_boundary
)
1382 int reg_parm_stack_space
;
1383 struct args_size
*args_size
;
1384 int preferred_stack_boundary ATTRIBUTE_UNUSED
;
1386 int unadjusted_args_size
= args_size
->constant
;
1388 /* For accumulate outgoing args mode we don't need to align, since the frame
1389 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1390 backends from generating misaligned frame sizes. */
1391 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1392 preferred_stack_boundary
= STACK_BOUNDARY
;
1394 /* Compute the actual size of the argument block required. The variable
1395 and constant sizes must be combined, the size may have to be rounded,
1396 and there may be a minimum required size. */
1400 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1401 args_size
->constant
= 0;
1403 preferred_stack_boundary
/= BITS_PER_UNIT
;
1404 if (preferred_stack_boundary
> 1)
1406 /* We don't handle this case yet. To handle it correctly we have
1407 to add the delta, round and subtract the delta.
1408 Currently no machine description requires this support. */
1409 if (stack_pointer_delta
& (preferred_stack_boundary
- 1))
1411 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1414 if (reg_parm_stack_space
> 0)
1417 = size_binop (MAX_EXPR
, args_size
->var
,
1418 ssize_int (reg_parm_stack_space
));
1420 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1421 /* The area corresponding to register parameters is not to count in
1422 the size of the block we need. So make the adjustment. */
1424 = size_binop (MINUS_EXPR
, args_size
->var
,
1425 ssize_int (reg_parm_stack_space
));
1431 preferred_stack_boundary
/= BITS_PER_UNIT
;
1432 if (preferred_stack_boundary
< 1)
1433 preferred_stack_boundary
= 1;
1434 args_size
->constant
= (((args_size
->constant
1435 + stack_pointer_delta
1436 + preferred_stack_boundary
- 1)
1437 / preferred_stack_boundary
1438 * preferred_stack_boundary
)
1439 - stack_pointer_delta
);
1441 args_size
->constant
= MAX (args_size
->constant
,
1442 reg_parm_stack_space
);
1444 #ifdef MAYBE_REG_PARM_STACK_SPACE
1445 if (reg_parm_stack_space
== 0)
1446 args_size
->constant
= 0;
1449 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1450 args_size
->constant
-= reg_parm_stack_space
;
1453 return unadjusted_args_size
;
1456 /* Precompute parameters as needed for a function call.
1458 FLAGS is mask of ECF_* constants.
1460 NUM_ACTUALS is the number of arguments.
1462 ARGS is an array containing information for each argument; this
1463 routine fills in the INITIAL_VALUE and VALUE fields for each
1464 precomputed argument. */
1467 precompute_arguments (flags
, num_actuals
, args
)
1470 struct arg_data
*args
;
1474 /* If this function call is cse'able, precompute all the parameters.
1475 Note that if the parameter is constructed into a temporary, this will
1476 cause an additional copy because the parameter will be constructed
1477 into a temporary location and then copied into the outgoing arguments.
1478 If a parameter contains a call to alloca and this function uses the
1479 stack, precompute the parameter. */
1481 /* If we preallocated the stack space, and some arguments must be passed
1482 on the stack, then we must precompute any parameter which contains a
1483 function call which will store arguments on the stack.
1484 Otherwise, evaluating the parameter may clobber previous parameters
1485 which have already been stored into the stack. (we have code to avoid
1486 such case by saving the outgoing stack arguments, but it results in
1489 for (i
= 0; i
< num_actuals
; i
++)
1490 if ((flags
& ECF_LIBCALL_BLOCK
)
1491 || calls_function (args
[i
].tree_value
, !ACCUMULATE_OUTGOING_ARGS
))
1493 enum machine_mode mode
;
1495 /* If this is an addressable type, we cannot pre-evaluate it. */
1496 if (TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
)))
1500 = expand_expr (args
[i
].tree_value
, NULL_RTX
, VOIDmode
, 0);
1502 /* ANSI doesn't require a sequence point here,
1503 but PCC has one, so this will avoid some problems. */
1506 args
[i
].initial_value
= args
[i
].value
1507 = protect_from_queue (args
[i
].value
, 0);
1509 mode
= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
));
1510 if (mode
!= args
[i
].mode
)
1513 = convert_modes (args
[i
].mode
, mode
,
1514 args
[i
].value
, args
[i
].unsignedp
);
1515 #ifdef PROMOTE_FOR_CALL_ONLY
1516 /* CSE will replace this only if it contains args[i].value
1517 pseudo, so convert it down to the declared mode using
1519 if (GET_CODE (args
[i
].value
) == REG
1520 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
)
1522 args
[i
].initial_value
1523 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1524 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1525 SUBREG_PROMOTED_UNSIGNED_SET (args
[i
].initial_value
,
1533 /* Given the current state of MUST_PREALLOCATE and information about
1534 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1535 compute and return the final value for MUST_PREALLOCATE. */
1538 finalize_must_preallocate (must_preallocate
, num_actuals
, args
, args_size
)
1539 int must_preallocate
;
1541 struct arg_data
*args
;
1542 struct args_size
*args_size
;
1544 /* See if we have or want to preallocate stack space.
1546 If we would have to push a partially-in-regs parm
1547 before other stack parms, preallocate stack space instead.
1549 If the size of some parm is not a multiple of the required stack
1550 alignment, we must preallocate.
1552 If the total size of arguments that would otherwise create a copy in
1553 a temporary (such as a CALL) is more than half the total argument list
1554 size, preallocation is faster.
1556 Another reason to preallocate is if we have a machine (like the m88k)
1557 where stack alignment is required to be maintained between every
1558 pair of insns, not just when the call is made. However, we assume here
1559 that such machines either do not have push insns (and hence preallocation
1560 would occur anyway) or the problem is taken care of with
1563 if (! must_preallocate
)
1565 int partial_seen
= 0;
1566 int copy_to_evaluate_size
= 0;
1569 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1571 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1573 else if (partial_seen
&& args
[i
].reg
== 0)
1574 must_preallocate
= 1;
1576 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1577 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1578 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1579 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1580 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1581 copy_to_evaluate_size
1582 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1585 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1586 && args_size
->constant
> 0)
1587 must_preallocate
= 1;
1589 return must_preallocate
;
1592 /* If we preallocated stack space, compute the address of each argument
1593 and store it into the ARGS array.
1595 We need not ensure it is a valid memory address here; it will be
1596 validized when it is used.
1598 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1601 compute_argument_addresses (args
, argblock
, num_actuals
)
1602 struct arg_data
*args
;
1608 rtx arg_reg
= argblock
;
1609 int i
, arg_offset
= 0;
1611 if (GET_CODE (argblock
) == PLUS
)
1612 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1614 for (i
= 0; i
< num_actuals
; i
++)
1616 rtx offset
= ARGS_SIZE_RTX (args
[i
].offset
);
1617 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].slot_offset
);
1620 /* Skip this parm if it will not be passed on the stack. */
1621 if (! args
[i
].pass_on_stack
&& args
[i
].reg
!= 0)
1624 if (GET_CODE (offset
) == CONST_INT
)
1625 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1627 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1629 addr
= plus_constant (addr
, arg_offset
);
1630 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1631 set_mem_align (args
[i
].stack
, PARM_BOUNDARY
);
1632 set_mem_attributes (args
[i
].stack
,
1633 TREE_TYPE (args
[i
].tree_value
), 1);
1635 if (GET_CODE (slot_offset
) == CONST_INT
)
1636 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1638 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1640 addr
= plus_constant (addr
, arg_offset
);
1641 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1642 set_mem_align (args
[i
].stack_slot
, PARM_BOUNDARY
);
1643 set_mem_attributes (args
[i
].stack_slot
,
1644 TREE_TYPE (args
[i
].tree_value
), 1);
1646 /* Function incoming arguments may overlap with sibling call
1647 outgoing arguments and we cannot allow reordering of reads
1648 from function arguments with stores to outgoing arguments
1649 of sibling calls. */
1650 set_mem_alias_set (args
[i
].stack
, 0);
1651 set_mem_alias_set (args
[i
].stack_slot
, 0);
1656 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1657 in a call instruction.
1659 FNDECL is the tree node for the target function. For an indirect call
1660 FNDECL will be NULL_TREE.
1662 ADDR is the operand 0 of CALL_EXPR for this call. */
1665 rtx_for_function_call (fndecl
, addr
)
1671 /* Get the function to call, in the form of RTL. */
1674 /* If this is the first use of the function, see if we need to
1675 make an external definition for it. */
1676 if (! TREE_USED (fndecl
))
1678 assemble_external (fndecl
);
1679 TREE_USED (fndecl
) = 1;
1682 /* Get a SYMBOL_REF rtx for the function address. */
1683 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1686 /* Generate an rtx (probably a pseudo-register) for the address. */
1689 funexp
= expand_expr (addr
, NULL_RTX
, VOIDmode
, 0);
1690 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1696 /* Do the register loads required for any wholly-register parms or any
1697 parms which are passed both on the stack and in a register. Their
1698 expressions were already evaluated.
1700 Mark all register-parms as living through the call, putting these USE
1701 insns in the CALL_INSN_FUNCTION_USAGE field.
1703 When IS_SIBCALL, perform the check_sibcall_overlap_argument_overlap
1704 checking, setting *SIBCALL_FAILURE if appropriate. */
1707 load_register_parameters (args
, num_actuals
, call_fusage
, flags
,
1708 is_sibcall
, sibcall_failure
)
1709 struct arg_data
*args
;
1714 int *sibcall_failure
;
1718 #ifdef LOAD_ARGS_REVERSED
1719 for (i
= num_actuals
- 1; i
>= 0; i
--)
1721 for (i
= 0; i
< num_actuals
; i
++)
1724 rtx reg
= ((flags
& ECF_SIBCALL
)
1725 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1726 int partial
= args
[i
].partial
;
1731 rtx before_arg
= get_last_insn ();
1732 /* Set to non-negative if must move a word at a time, even if just
1733 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1734 we just use a normal move insn. This value can be zero if the
1735 argument is a zero size structure with no fields. */
1736 nregs
= (partial
? partial
1737 : (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1738 ? ((int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
))
1739 + (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
)
1742 /* Handle calls that pass values in multiple non-contiguous
1743 locations. The Irix 6 ABI has examples of this. */
1745 if (GET_CODE (reg
) == PARALLEL
)
1746 emit_group_load (reg
, args
[i
].value
,
1747 int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
)));
1749 /* If simple case, just do move. If normal partial, store_one_arg
1750 has already loaded the register for us. In all other cases,
1751 load the register(s) from memory. */
1753 else if (nregs
== -1)
1754 emit_move_insn (reg
, args
[i
].value
);
1756 /* If we have pre-computed the values to put in the registers in
1757 the case of non-aligned structures, copy them in now. */
1759 else if (args
[i
].n_aligned_regs
!= 0)
1760 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1761 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1762 args
[i
].aligned_regs
[j
]);
1764 else if (partial
== 0 || args
[i
].pass_on_stack
)
1765 move_block_to_reg (REGNO (reg
),
1766 validize_mem (args
[i
].value
), nregs
,
1769 /* When a parameter is a block, and perhaps in other cases, it is
1770 possible that it did a load from an argument slot that was
1771 already clobbered. */
1773 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
1774 *sibcall_failure
= 1;
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
) (size_t) - 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 i
= reg_parm_stack_space
;
1834 if (i
> highest_outgoing_arg_in_use
)
1835 i
= highest_outgoing_arg_in_use
;
1836 while (--i
>= 0 && stack_usage_map
[i
] == 0)
1839 if (stack_arg_under_construction
|| i
>= 0)
1842 = before_call
? NEXT_INSN (before_call
) : get_insns ();
1843 rtx insn
= NULL_RTX
, seq
;
1845 /* Look for a call in the inline function code.
1846 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1847 nonzero then there is a call and it is not necessary
1848 to scan the insns. */
1850 if (DECL_SAVED_INSNS (fndecl
)->outgoing_args_size
== 0)
1851 for (insn
= first_insn
; insn
; insn
= NEXT_INSN (insn
))
1852 if (GET_CODE (insn
) == CALL_INSN
)
1857 /* Reserve enough stack space so that the largest
1858 argument list of any function call in the inline
1859 function does not overlap the argument list being
1860 evaluated. This is usually an overestimate because
1861 allocate_dynamic_stack_space reserves space for an
1862 outgoing argument list in addition to the requested
1863 space, but there is no way to ask for stack space such
1864 that an argument list of a certain length can be
1867 Add the stack space reserved for register arguments, if
1868 any, in the inline function. What is really needed is the
1869 largest value of reg_parm_stack_space in the inline
1870 function, but that is not available. Using the current
1871 value of reg_parm_stack_space is wrong, but gives
1872 correct results on all supported machines. */
1874 int adjust
= (DECL_SAVED_INSNS (fndecl
)->outgoing_args_size
1875 + reg_parm_stack_space
);
1878 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
1879 allocate_dynamic_stack_space (GEN_INT (adjust
),
1880 NULL_RTX
, BITS_PER_UNIT
);
1883 emit_insn_before (seq
, first_insn
);
1884 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1889 /* If the result is equivalent to TARGET, return TARGET to simplify
1890 checks in store_expr. They can be equivalent but not equal in the
1891 case of a function that returns BLKmode. */
1892 if (temp
!= target
&& rtx_equal_p (temp
, target
))
1897 /* If inlining failed, mark FNDECL as needing to be compiled
1898 separately after all. If function was declared inline,
1900 if (DECL_INLINE (fndecl
) && warn_inline
&& !flag_no_inline
1901 && optimize
> 0 && !TREE_ADDRESSABLE (fndecl
))
1903 warning_with_decl (fndecl
, "inlining failed in call to `%s'");
1904 warning ("called from here");
1906 (*lang_hooks
.mark_addressable
) (fndecl
);
1907 return (rtx
) (size_t) - 1;
1910 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1911 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1912 bytes, then we would need to push some additional bytes to pad the
1913 arguments. So, we compute an adjust to the stack pointer for an
1914 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1915 bytes. Then, when the arguments are pushed the stack will be perfectly
1916 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1917 be popped after the call. Returns the adjustment. */
1920 combine_pending_stack_adjustment_and_call (unadjusted_args_size
,
1922 preferred_unit_stack_boundary
)
1923 int unadjusted_args_size
;
1924 struct args_size
*args_size
;
1925 int preferred_unit_stack_boundary
;
1927 /* The number of bytes to pop so that the stack will be
1928 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1929 HOST_WIDE_INT adjustment
;
1930 /* The alignment of the stack after the arguments are pushed, if we
1931 just pushed the arguments without adjust the stack here. */
1932 HOST_WIDE_INT unadjusted_alignment
;
1934 unadjusted_alignment
1935 = ((stack_pointer_delta
+ unadjusted_args_size
)
1936 % preferred_unit_stack_boundary
);
1938 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1939 as possible -- leaving just enough left to cancel out the
1940 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1941 PENDING_STACK_ADJUST is non-negative, and congruent to
1942 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1944 /* Begin by trying to pop all the bytes. */
1945 unadjusted_alignment
1946 = (unadjusted_alignment
1947 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1948 adjustment
= pending_stack_adjust
;
1949 /* Push enough additional bytes that the stack will be aligned
1950 after the arguments are pushed. */
1951 if (preferred_unit_stack_boundary
> 1)
1953 if (unadjusted_alignment
> 0)
1954 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1956 adjustment
+= unadjusted_alignment
;
1959 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1960 bytes after the call. The right number is the entire
1961 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1962 by the arguments in the first place. */
1964 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1969 /* Scan X expression if it does not dereference any argument slots
1970 we already clobbered by tail call arguments (as noted in stored_args_map
1972 Return nonzero if X expression dereferences such argument slots,
1976 check_sibcall_argument_overlap_1 (x
)
1987 code
= GET_CODE (x
);
1991 if (XEXP (x
, 0) == current_function_internal_arg_pointer
)
1993 else if (GET_CODE (XEXP (x
, 0)) == PLUS
1994 && XEXP (XEXP (x
, 0), 0) ==
1995 current_function_internal_arg_pointer
1996 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
)
1997 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
2001 #ifdef ARGS_GROW_DOWNWARD
2002 i
= -i
- GET_MODE_SIZE (GET_MODE (x
));
2005 for (k
= 0; k
< GET_MODE_SIZE (GET_MODE (x
)); k
++)
2006 if (i
+ k
< stored_args_map
->n_bits
2007 && TEST_BIT (stored_args_map
, i
+ k
))
2013 /* Scan all subexpressions. */
2014 fmt
= GET_RTX_FORMAT (code
);
2015 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
2019 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
2022 else if (*fmt
== 'E')
2024 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2025 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
2032 /* Scan sequence after INSN if it does not dereference any argument slots
2033 we already clobbered by tail call arguments (as noted in stored_args_map
2034 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2035 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2036 should be 0). Return nonzero if sequence after INSN dereferences such argument
2037 slots, zero otherwise. */
2040 check_sibcall_argument_overlap (insn
, arg
, mark_stored_args_map
)
2042 struct arg_data
*arg
;
2043 int mark_stored_args_map
;
2047 if (insn
== NULL_RTX
)
2048 insn
= get_insns ();
2050 insn
= NEXT_INSN (insn
);
2052 for (; insn
; insn
= NEXT_INSN (insn
))
2054 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
2057 if (mark_stored_args_map
)
2059 #ifdef ARGS_GROW_DOWNWARD
2060 low
= -arg
->slot_offset
.constant
- arg
->size
.constant
;
2062 low
= arg
->slot_offset
.constant
;
2065 for (high
= low
+ arg
->size
.constant
; low
< high
; low
++)
2066 SET_BIT (stored_args_map
, low
);
2068 return insn
!= NULL_RTX
;
2075 switch (unsafe_for_reeval (t
))
2080 case 1: /* Mildly unsafe. */
2081 t
= unsave_expr (t
);
2084 case 2: /* Wildly unsafe. */
2086 tree var
= build_decl (VAR_DECL
, NULL_TREE
,
2089 expand_expr (t
, NULL_RTX
, VOIDmode
, EXPAND_NORMAL
));
2100 /* Generate all the code for a function call
2101 and return an rtx for its value.
2102 Store the value in TARGET (specified as an rtx) if convenient.
2103 If the value is stored in TARGET then TARGET is returned.
2104 If IGNORE is nonzero, then we ignore the value of the function call. */
2107 expand_call (exp
, target
, ignore
)
2112 /* Nonzero if we are currently expanding a call. */
2113 static int currently_expanding_call
= 0;
2115 /* List of actual parameters. */
2116 tree actparms
= TREE_OPERAND (exp
, 1);
2117 /* RTX for the function to be called. */
2119 /* Sequence of insns to perform a tail recursive "call". */
2120 rtx tail_recursion_insns
= NULL_RTX
;
2121 /* Sequence of insns to perform a normal "call". */
2122 rtx normal_call_insns
= NULL_RTX
;
2123 /* Sequence of insns to perform a tail recursive "call". */
2124 rtx tail_call_insns
= NULL_RTX
;
2125 /* Data type of the function. */
2127 /* Declaration of the function being called,
2128 or 0 if the function is computed (not known by name). */
2131 int try_tail_call
= 1;
2132 int try_tail_recursion
= 1;
2135 /* Register in which non-BLKmode value will be returned,
2136 or 0 if no value or if value is BLKmode. */
2138 /* Address where we should return a BLKmode value;
2139 0 if value not BLKmode. */
2140 rtx structure_value_addr
= 0;
2141 /* Nonzero if that address is being passed by treating it as
2142 an extra, implicit first parameter. Otherwise,
2143 it is passed by being copied directly into struct_value_rtx. */
2144 int structure_value_addr_parm
= 0;
2145 /* Size of aggregate value wanted, or zero if none wanted
2146 or if we are using the non-reentrant PCC calling convention
2147 or expecting the value in registers. */
2148 HOST_WIDE_INT struct_value_size
= 0;
2149 /* Nonzero if called function returns an aggregate in memory PCC style,
2150 by returning the address of where to find it. */
2151 int pcc_struct_value
= 0;
2153 /* Number of actual parameters in this call, including struct value addr. */
2155 /* Number of named args. Args after this are anonymous ones
2156 and they must all go on the stack. */
2159 /* Vector of information about each argument.
2160 Arguments are numbered in the order they will be pushed,
2161 not the order they are written. */
2162 struct arg_data
*args
;
2164 /* Total size in bytes of all the stack-parms scanned so far. */
2165 struct args_size args_size
;
2166 struct args_size adjusted_args_size
;
2167 /* Size of arguments before any adjustments (such as rounding). */
2168 int unadjusted_args_size
;
2169 /* Data on reg parms scanned so far. */
2170 CUMULATIVE_ARGS args_so_far
;
2171 /* Nonzero if a reg parm has been scanned. */
2173 /* Nonzero if this is an indirect function call. */
2175 /* Nonzero if we must avoid push-insns in the args for this call.
2176 If stack space is allocated for register parameters, but not by the
2177 caller, then it is preallocated in the fixed part of the stack frame.
2178 So the entire argument block must then be preallocated (i.e., we
2179 ignore PUSH_ROUNDING in that case). */
2181 int must_preallocate
= !PUSH_ARGS
;
2183 /* Size of the stack reserved for parameter registers. */
2184 int reg_parm_stack_space
= 0;
2186 /* Address of space preallocated for stack parms
2187 (on machines that lack push insns), or 0 if space not preallocated. */
2190 /* Mask of ECF_ flags. */
2192 /* Nonzero if this is a call to an inline function. */
2193 int is_integrable
= 0;
2194 #ifdef REG_PARM_STACK_SPACE
2195 /* Define the boundary of the register parm stack space that needs to be
2197 int low_to_save
, high_to_save
;
2198 rtx save_area
= 0; /* Place that it is saved */
2201 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
2202 char *initial_stack_usage_map
= stack_usage_map
;
2204 int old_stack_allocated
;
2206 /* State variables to track stack modifications. */
2207 rtx old_stack_level
= 0;
2208 int old_stack_arg_under_construction
= 0;
2209 int old_pending_adj
= 0;
2210 int old_inhibit_defer_pop
= inhibit_defer_pop
;
2212 /* Some stack pointer alterations we make are performed via
2213 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2214 which we then also need to save/restore along the way. */
2215 int old_stack_pointer_delta
= 0;
2218 tree p
= TREE_OPERAND (exp
, 0);
2219 tree addr
= TREE_OPERAND (exp
, 0);
2221 /* The alignment of the stack, in bits. */
2222 HOST_WIDE_INT preferred_stack_boundary
;
2223 /* The alignment of the stack, in bytes. */
2224 HOST_WIDE_INT preferred_unit_stack_boundary
;
2226 /* See if this is "nothrow" function call. */
2227 if (TREE_NOTHROW (exp
))
2228 flags
|= ECF_NOTHROW
;
2230 /* See if we can find a DECL-node for the actual function.
2231 As a result, decide whether this is a call to an integrable function. */
2233 fndecl
= get_callee_fndecl (exp
);
2237 && fndecl
!= current_function_decl
2238 && DECL_INLINE (fndecl
)
2239 && DECL_SAVED_INSNS (fndecl
)
2240 && DECL_SAVED_INSNS (fndecl
)->inlinable
)
2242 else if (! TREE_ADDRESSABLE (fndecl
))
2244 /* In case this function later becomes inlinable,
2245 record that there was already a non-inline call to it.
2247 Use abstraction instead of setting TREE_ADDRESSABLE
2249 if (DECL_INLINE (fndecl
) && warn_inline
&& !flag_no_inline
2252 warning_with_decl (fndecl
, "can't inline call to `%s'");
2253 warning ("called from here");
2255 (*lang_hooks
.mark_addressable
) (fndecl
);
2258 flags
|= flags_from_decl_or_type (fndecl
);
2261 /* If we don't have specific function to call, see if we have a
2262 attributes set in the type. */
2264 flags
|= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p
)));
2266 #ifdef REG_PARM_STACK_SPACE
2267 #ifdef MAYBE_REG_PARM_STACK_SPACE
2268 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
2270 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
2274 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2275 if (reg_parm_stack_space
> 0 && PUSH_ARGS
)
2276 must_preallocate
= 1;
2279 /* Warn if this value is an aggregate type,
2280 regardless of which calling convention we are using for it. */
2281 if (warn_aggregate_return
&& AGGREGATE_TYPE_P (TREE_TYPE (exp
)))
2282 warning ("function call has aggregate value");
2284 /* Set up a place to return a structure. */
2286 /* Cater to broken compilers. */
2287 if (aggregate_value_p (exp
))
2289 /* This call returns a big structure. */
2290 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
2292 #ifdef PCC_STATIC_STRUCT_RETURN
2294 pcc_struct_value
= 1;
2295 /* Easier than making that case work right. */
2298 /* In case this is a static function, note that it has been
2300 if (! TREE_ADDRESSABLE (fndecl
))
2301 (*lang_hooks
.mark_addressable
) (fndecl
);
2305 #else /* not PCC_STATIC_STRUCT_RETURN */
2307 struct_value_size
= int_size_in_bytes (TREE_TYPE (exp
));
2309 if (CALL_EXPR_HAS_RETURN_SLOT_ADDR (exp
))
2311 /* The structure value address arg is already in actparms.
2312 Pull it out. It might be nice to just leave it there, but
2313 we need to set structure_value_addr. */
2314 tree return_arg
= TREE_VALUE (actparms
);
2315 actparms
= TREE_CHAIN (actparms
);
2316 structure_value_addr
= expand_expr (return_arg
, NULL_RTX
,
2317 VOIDmode
, EXPAND_NORMAL
);
2319 else if (target
&& GET_CODE (target
) == MEM
)
2320 structure_value_addr
= XEXP (target
, 0);
2323 /* For variable-sized objects, we must be called with a target
2324 specified. If we were to allocate space on the stack here,
2325 we would have no way of knowing when to free it. */
2326 rtx d
= assign_temp (TREE_TYPE (exp
), 1, 1, 1);
2328 mark_temp_addr_taken (d
);
2329 structure_value_addr
= XEXP (d
, 0);
2333 #endif /* not PCC_STATIC_STRUCT_RETURN */
2336 /* If called function is inline, try to integrate it. */
2340 rtx temp
= try_to_integrate (fndecl
, actparms
, target
,
2341 ignore
, TREE_TYPE (exp
),
2342 structure_value_addr
);
2343 if (temp
!= (rtx
) (size_t) - 1)
2347 /* Figure out the amount to which the stack should be aligned. */
2348 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2351 struct cgraph_rtl_info
*i
= cgraph_rtl_info (fndecl
);
2352 if (i
&& i
->preferred_incoming_stack_boundary
)
2353 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
2356 /* Operand 0 is a pointer-to-function; get the type of the function. */
2357 funtype
= TREE_TYPE (addr
);
2358 if (! POINTER_TYPE_P (funtype
))
2360 funtype
= TREE_TYPE (funtype
);
2362 /* See if this is a call to a function that can return more than once
2363 or a call to longjmp or malloc. */
2364 flags
|= special_function_p (fndecl
, flags
);
2366 if (flags
& ECF_MAY_BE_ALLOCA
)
2367 current_function_calls_alloca
= 1;
2369 /* If struct_value_rtx is 0, it means pass the address
2370 as if it were an extra parameter. */
2371 if (structure_value_addr
&& struct_value_rtx
== 0)
2373 /* If structure_value_addr is a REG other than
2374 virtual_outgoing_args_rtx, we can use always use it. If it
2375 is not a REG, we must always copy it into a register.
2376 If it is virtual_outgoing_args_rtx, we must copy it to another
2377 register in some cases. */
2378 rtx temp
= (GET_CODE (structure_value_addr
) != REG
2379 || (ACCUMULATE_OUTGOING_ARGS
2380 && stack_arg_under_construction
2381 && structure_value_addr
== virtual_outgoing_args_rtx
)
2382 ? copy_addr_to_reg (structure_value_addr
)
2383 : structure_value_addr
);
2386 = tree_cons (error_mark_node
,
2387 make_tree (build_pointer_type (TREE_TYPE (funtype
)),
2390 structure_value_addr_parm
= 1;
2393 /* Count the arguments and set NUM_ACTUALS. */
2394 for (p
= actparms
, num_actuals
= 0; p
; p
= TREE_CHAIN (p
))
2397 /* Compute number of named args.
2398 Normally, don't include the last named arg if anonymous args follow.
2399 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2400 (If no anonymous args follow, the result of list_length is actually
2401 one too large. This is harmless.)
2403 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2404 zero, this machine will be able to place unnamed args that were
2405 passed in registers into the stack. So treat all args as named.
2406 This allows the insns emitting for a specific argument list to be
2407 independent of the function declaration.
2409 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2410 reliable way to pass unnamed args in registers, so we must force
2411 them into memory. */
2413 if ((STRICT_ARGUMENT_NAMING
2414 || ! PRETEND_OUTGOING_VARARGS_NAMED
)
2415 && TYPE_ARG_TYPES (funtype
) != 0)
2417 = (list_length (TYPE_ARG_TYPES (funtype
))
2418 /* Don't include the last named arg. */
2419 - (STRICT_ARGUMENT_NAMING
? 0 : 1)
2420 /* Count the struct value address, if it is passed as a parm. */
2421 + structure_value_addr_parm
);
2423 /* If we know nothing, treat all args as named. */
2424 n_named_args
= num_actuals
;
2426 /* Start updating where the next arg would go.
2428 On some machines (such as the PA) indirect calls have a different
2429 calling convention than normal calls. The last argument in
2430 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2432 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, fndecl
);
2434 /* Make a vector to hold all the information about each arg. */
2435 args
= (struct arg_data
*) alloca (num_actuals
* sizeof (struct arg_data
));
2436 memset ((char *) args
, 0, num_actuals
* sizeof (struct arg_data
));
2438 /* Build up entries in the ARGS array, compute the size of the
2439 arguments into ARGS_SIZE, etc. */
2440 initialize_argument_information (num_actuals
, args
, &args_size
,
2441 n_named_args
, actparms
, fndecl
,
2442 &args_so_far
, reg_parm_stack_space
,
2443 &old_stack_level
, &old_pending_adj
,
2444 &must_preallocate
, &flags
);
2448 /* If this function requires a variable-sized argument list, don't
2449 try to make a cse'able block for this call. We may be able to
2450 do this eventually, but it is too complicated to keep track of
2451 what insns go in the cse'able block and which don't. */
2453 flags
&= ~ECF_LIBCALL_BLOCK
;
2454 must_preallocate
= 1;
2457 /* Now make final decision about preallocating stack space. */
2458 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2462 /* If the structure value address will reference the stack pointer, we
2463 must stabilize it. We don't need to do this if we know that we are
2464 not going to adjust the stack pointer in processing this call. */
2466 if (structure_value_addr
2467 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2468 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2469 structure_value_addr
))
2471 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2472 structure_value_addr
= copy_to_reg (structure_value_addr
);
2474 /* Tail calls can make things harder to debug, and we're traditionally
2475 pushed these optimizations into -O2. Don't try if we're already
2476 expanding a call, as that means we're an argument. Don't try if
2477 there's cleanups, as we know there's code to follow the call.
2479 If rtx_equal_function_value_matters is false, that means we've
2480 finished with regular parsing. Which means that some of the
2481 machinery we use to generate tail-calls is no longer in place.
2482 This is most often true of sjlj-exceptions, which we couldn't
2483 tail-call to anyway. */
2485 if (currently_expanding_call
++ != 0
2486 || !flag_optimize_sibling_calls
2487 || !rtx_equal_function_value_matters
2488 || any_pending_cleanups (1)
2490 try_tail_call
= try_tail_recursion
= 0;
2492 /* Tail recursion fails, when we are not dealing with recursive calls. */
2493 if (!try_tail_recursion
2494 || TREE_CODE (addr
) != ADDR_EXPR
2495 || TREE_OPERAND (addr
, 0) != current_function_decl
)
2496 try_tail_recursion
= 0;
2498 /* Rest of purposes for tail call optimizations to fail. */
2500 #ifdef HAVE_sibcall_epilogue
2501 !HAVE_sibcall_epilogue
2506 /* Doing sibling call optimization needs some work, since
2507 structure_value_addr can be allocated on the stack.
2508 It does not seem worth the effort since few optimizable
2509 sibling calls will return a structure. */
2510 || structure_value_addr
!= NULL_RTX
2511 /* Check whether the target is able to optimize the call
2513 || !(*targetm
.function_ok_for_sibcall
) (fndecl
, exp
)
2514 /* Functions that do not return exactly once may not be sibcall
2516 || (flags
& (ECF_RETURNS_TWICE
| ECF_LONGJMP
| ECF_NORETURN
))
2517 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
)))
2518 /* If the called function is nested in the current one, it might access
2519 some of the caller's arguments, but could clobber them beforehand if
2520 the argument areas are shared. */
2521 || decl_function_context (fndecl
) == current_function_decl
2522 /* If this function requires more stack slots than the current
2523 function, we cannot change it into a sibling call. */
2524 || args_size
.constant
> current_function_args_size
2525 /* If the callee pops its own arguments, then it must pop exactly
2526 the same number of arguments as the current function. */
2527 || RETURN_POPS_ARGS (fndecl
, funtype
, args_size
.constant
)
2528 != RETURN_POPS_ARGS (current_function_decl
,
2529 TREE_TYPE (current_function_decl
),
2530 current_function_args_size
))
2533 if (try_tail_call
|| try_tail_recursion
)
2536 actparms
= NULL_TREE
;
2537 /* Ok, we're going to give the tail call the old college try.
2538 This means we're going to evaluate the function arguments
2539 up to three times. There are two degrees of badness we can
2540 encounter, those that can be unsaved and those that can't.
2541 (See unsafe_for_reeval commentary for details.)
2543 Generate a new argument list. Pass safe arguments through
2544 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2545 For hard badness, evaluate them now and put their resulting
2546 rtx in a temporary VAR_DECL.
2548 initialize_argument_information has ordered the array for the
2549 order to be pushed, and we must remember this when reconstructing
2550 the original argument order. */
2552 if (PUSH_ARGS_REVERSED
)
2561 i
= num_actuals
- 1;
2565 for (; i
!= end
; i
+= inc
)
2567 args
[i
].tree_value
= fix_unsafe_tree (args
[i
].tree_value
);
2568 /* We need to build actparms for optimize_tail_recursion. We can
2569 safely trash away TREE_PURPOSE, since it is unused by this
2571 if (try_tail_recursion
)
2572 actparms
= tree_cons (NULL_TREE
, args
[i
].tree_value
, actparms
);
2574 /* Do the same for the function address if it is an expression. */
2576 addr
= fix_unsafe_tree (addr
);
2577 /* Expanding one of those dangerous arguments could have added
2578 cleanups, but otherwise give it a whirl. */
2579 if (any_pending_cleanups (1))
2580 try_tail_call
= try_tail_recursion
= 0;
2583 /* Generate a tail recursion sequence when calling ourselves. */
2585 if (try_tail_recursion
)
2587 /* We want to emit any pending stack adjustments before the tail
2588 recursion "call". That way we know any adjustment after the tail
2589 recursion call can be ignored if we indeed use the tail recursion
2591 int save_pending_stack_adjust
= pending_stack_adjust
;
2592 int save_stack_pointer_delta
= stack_pointer_delta
;
2594 /* Emit any queued insns now; otherwise they would end up in
2595 only one of the alternates. */
2598 /* Use a new sequence to hold any RTL we generate. We do not even
2599 know if we will use this RTL yet. The final decision can not be
2600 made until after RTL generation for the entire function is
2603 /* If expanding any of the arguments creates cleanups, we can't
2604 do a tailcall. So, we'll need to pop the pending cleanups
2605 list. If, however, all goes well, and there are no cleanups
2606 then the call to expand_start_target_temps will have no
2608 expand_start_target_temps ();
2609 if (optimize_tail_recursion (actparms
, get_last_insn ()))
2611 if (any_pending_cleanups (1))
2612 try_tail_call
= try_tail_recursion
= 0;
2614 tail_recursion_insns
= get_insns ();
2616 expand_end_target_temps ();
2619 /* Restore the original pending stack adjustment for the sibling and
2620 normal call cases below. */
2621 pending_stack_adjust
= save_pending_stack_adjust
;
2622 stack_pointer_delta
= save_stack_pointer_delta
;
2625 if (profile_arc_flag
&& (flags
& ECF_FORK_OR_EXEC
))
2627 /* A fork duplicates the profile information, and an exec discards
2628 it. We can't rely on fork/exec to be paired. So write out the
2629 profile information we have gathered so far, and clear it. */
2630 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2631 is subject to race conditions, just as with multithreaded
2634 emit_library_call (gcov_flush_libfunc
, LCT_ALWAYS_RETURN
, VOIDmode
, 0);
2637 /* Ensure current function's preferred stack boundary is at least
2638 what we need. We don't have to increase alignment for recursive
2640 if (cfun
->preferred_stack_boundary
< preferred_stack_boundary
2641 && fndecl
!= current_function_decl
)
2642 cfun
->preferred_stack_boundary
= preferred_stack_boundary
;
2643 if (fndecl
== current_function_decl
)
2644 cfun
->recursive_call_emit
= true;
2646 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2648 function_call_count
++;
2650 /* We want to make two insn chains; one for a sibling call, the other
2651 for a normal call. We will select one of the two chains after
2652 initial RTL generation is complete. */
2653 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
2655 int sibcall_failure
= 0;
2656 /* We want to emit any pending stack adjustments before the tail
2657 recursion "call". That way we know any adjustment after the tail
2658 recursion call can be ignored if we indeed use the tail recursion
2660 int save_pending_stack_adjust
= 0;
2661 int save_stack_pointer_delta
= 0;
2663 rtx before_call
, next_arg_reg
;
2667 /* Emit any queued insns now; otherwise they would end up in
2668 only one of the alternates. */
2671 /* State variables we need to save and restore between
2673 save_pending_stack_adjust
= pending_stack_adjust
;
2674 save_stack_pointer_delta
= stack_pointer_delta
;
2677 flags
&= ~ECF_SIBCALL
;
2679 flags
|= ECF_SIBCALL
;
2681 /* Other state variables that we must reinitialize each time
2682 through the loop (that are not initialized by the loop itself). */
2686 /* Start a new sequence for the normal call case.
2688 From this point on, if the sibling call fails, we want to set
2689 sibcall_failure instead of continuing the loop. */
2694 /* We know at this point that there are not currently any
2695 pending cleanups. If, however, in the process of evaluating
2696 the arguments we were to create some, we'll need to be
2697 able to get rid of them. */
2698 expand_start_target_temps ();
2701 /* Don't let pending stack adjusts add up to too much.
2702 Also, do all pending adjustments now if there is any chance
2703 this might be a call to alloca or if we are expanding a sibling
2704 call sequence or if we are calling a function that is to return
2705 with stack pointer depressed. */
2706 if (pending_stack_adjust
>= 32
2707 || (pending_stack_adjust
> 0
2708 && (flags
& (ECF_MAY_BE_ALLOCA
| ECF_SP_DEPRESSED
)))
2710 do_pending_stack_adjust ();
2712 /* When calling a const function, we must pop the stack args right away,
2713 so that the pop is deleted or moved with the call. */
2714 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
2717 #ifdef FINAL_REG_PARM_STACK_SPACE
2718 reg_parm_stack_space
= FINAL_REG_PARM_STACK_SPACE (args_size
.constant
,
2721 /* Precompute any arguments as needed. */
2723 precompute_arguments (flags
, num_actuals
, args
);
2725 /* Now we are about to start emitting insns that can be deleted
2726 if a libcall is deleted. */
2727 if (pass
&& (flags
& (ECF_LIBCALL_BLOCK
| ECF_MALLOC
)))
2730 adjusted_args_size
= args_size
;
2731 /* Compute the actual size of the argument block required. The variable
2732 and constant sizes must be combined, the size may have to be rounded,
2733 and there may be a minimum required size. When generating a sibcall
2734 pattern, do not round up, since we'll be re-using whatever space our
2736 unadjusted_args_size
2737 = compute_argument_block_size (reg_parm_stack_space
,
2738 &adjusted_args_size
,
2740 : preferred_stack_boundary
));
2742 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2744 /* The argument block when performing a sibling call is the
2745 incoming argument block. */
2748 argblock
= virtual_incoming_args_rtx
;
2750 #ifdef STACK_GROWS_DOWNWARD
2751 = plus_constant (argblock
, current_function_pretend_args_size
);
2753 = plus_constant (argblock
, -current_function_pretend_args_size
);
2755 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2756 sbitmap_zero (stored_args_map
);
2759 /* If we have no actual push instructions, or shouldn't use them,
2760 make space for all args right now. */
2761 else if (adjusted_args_size
.var
!= 0)
2763 if (old_stack_level
== 0)
2765 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
2766 old_stack_pointer_delta
= stack_pointer_delta
;
2767 old_pending_adj
= pending_stack_adjust
;
2768 pending_stack_adjust
= 0;
2769 /* stack_arg_under_construction says whether a stack arg is
2770 being constructed at the old stack level. Pushing the stack
2771 gets a clean outgoing argument block. */
2772 old_stack_arg_under_construction
= stack_arg_under_construction
;
2773 stack_arg_under_construction
= 0;
2775 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2779 /* Note that we must go through the motions of allocating an argument
2780 block even if the size is zero because we may be storing args
2781 in the area reserved for register arguments, which may be part of
2784 int needed
= adjusted_args_size
.constant
;
2786 /* Store the maximum argument space used. It will be pushed by
2787 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2790 if (needed
> current_function_outgoing_args_size
)
2791 current_function_outgoing_args_size
= needed
;
2793 if (must_preallocate
)
2795 if (ACCUMULATE_OUTGOING_ARGS
)
2797 /* Since the stack pointer will never be pushed, it is
2798 possible for the evaluation of a parm to clobber
2799 something we have already written to the stack.
2800 Since most function calls on RISC machines do not use
2801 the stack, this is uncommon, but must work correctly.
2803 Therefore, we save any area of the stack that was already
2804 written and that we are using. Here we set up to do this
2805 by making a new stack usage map from the old one. The
2806 actual save will be done by store_one_arg.
2808 Another approach might be to try to reorder the argument
2809 evaluations to avoid this conflicting stack usage. */
2811 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2812 /* Since we will be writing into the entire argument area,
2813 the map must be allocated for its entire size, not just
2814 the part that is the responsibility of the caller. */
2815 needed
+= reg_parm_stack_space
;
2818 #ifdef ARGS_GROW_DOWNWARD
2819 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2822 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2826 = (char *) alloca (highest_outgoing_arg_in_use
);
2828 if (initial_highest_arg_in_use
)
2829 memcpy (stack_usage_map
, initial_stack_usage_map
,
2830 initial_highest_arg_in_use
);
2832 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2833 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2834 (highest_outgoing_arg_in_use
2835 - initial_highest_arg_in_use
));
2838 /* The address of the outgoing argument list must not be
2839 copied to a register here, because argblock would be left
2840 pointing to the wrong place after the call to
2841 allocate_dynamic_stack_space below. */
2843 argblock
= virtual_outgoing_args_rtx
;
2847 if (inhibit_defer_pop
== 0)
2849 /* Try to reuse some or all of the pending_stack_adjust
2850 to get this space. */
2852 = (combine_pending_stack_adjustment_and_call
2853 (unadjusted_args_size
,
2854 &adjusted_args_size
,
2855 preferred_unit_stack_boundary
));
2857 /* combine_pending_stack_adjustment_and_call computes
2858 an adjustment before the arguments are allocated.
2859 Account for them and see whether or not the stack
2860 needs to go up or down. */
2861 needed
= unadjusted_args_size
- needed
;
2865 /* We're releasing stack space. */
2866 /* ??? We can avoid any adjustment at all if we're
2867 already aligned. FIXME. */
2868 pending_stack_adjust
= -needed
;
2869 do_pending_stack_adjust ();
2873 /* We need to allocate space. We'll do that in
2874 push_block below. */
2875 pending_stack_adjust
= 0;
2878 /* Special case this because overhead of `push_block' in
2879 this case is non-trivial. */
2881 argblock
= virtual_outgoing_args_rtx
;
2883 argblock
= push_block (GEN_INT (needed
), 0, 0);
2885 /* We only really need to call `copy_to_reg' in the case
2886 where push insns are going to be used to pass ARGBLOCK
2887 to a function call in ARGS. In that case, the stack
2888 pointer changes value from the allocation point to the
2889 call point, and hence the value of
2890 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2891 as well always do it. */
2892 argblock
= copy_to_reg (argblock
);
2897 if (ACCUMULATE_OUTGOING_ARGS
)
2899 /* The save/restore code in store_one_arg handles all
2900 cases except one: a constructor call (including a C
2901 function returning a BLKmode struct) to initialize
2903 if (stack_arg_under_construction
)
2905 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2906 rtx push_size
= GEN_INT (reg_parm_stack_space
2907 + adjusted_args_size
.constant
);
2909 rtx push_size
= GEN_INT (adjusted_args_size
.constant
);
2911 if (old_stack_level
== 0)
2913 emit_stack_save (SAVE_BLOCK
, &old_stack_level
,
2915 old_stack_pointer_delta
= stack_pointer_delta
;
2916 old_pending_adj
= pending_stack_adjust
;
2917 pending_stack_adjust
= 0;
2918 /* stack_arg_under_construction says whether a stack
2919 arg is being constructed at the old stack level.
2920 Pushing the stack gets a clean outgoing argument
2922 old_stack_arg_under_construction
2923 = stack_arg_under_construction
;
2924 stack_arg_under_construction
= 0;
2925 /* Make a new map for the new argument list. */
2926 stack_usage_map
= (char *)
2927 alloca (highest_outgoing_arg_in_use
);
2928 memset (stack_usage_map
, 0, highest_outgoing_arg_in_use
);
2929 highest_outgoing_arg_in_use
= 0;
2931 allocate_dynamic_stack_space (push_size
, NULL_RTX
,
2935 /* If argument evaluation might modify the stack pointer,
2936 copy the address of the argument list to a register. */
2937 for (i
= 0; i
< num_actuals
; i
++)
2938 if (args
[i
].pass_on_stack
)
2940 argblock
= copy_addr_to_reg (argblock
);
2945 compute_argument_addresses (args
, argblock
, num_actuals
);
2947 /* If we push args individually in reverse order, perform stack alignment
2948 before the first push (the last arg). */
2949 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2950 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2952 /* When the stack adjustment is pending, we get better code
2953 by combining the adjustments. */
2954 if (pending_stack_adjust
2955 && ! (flags
& ECF_LIBCALL_BLOCK
)
2956 && ! inhibit_defer_pop
)
2958 pending_stack_adjust
2959 = (combine_pending_stack_adjustment_and_call
2960 (unadjusted_args_size
,
2961 &adjusted_args_size
,
2962 preferred_unit_stack_boundary
));
2963 do_pending_stack_adjust ();
2965 else if (argblock
== 0)
2966 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2967 - unadjusted_args_size
));
2969 /* Now that the stack is properly aligned, pops can't safely
2970 be deferred during the evaluation of the arguments. */
2973 funexp
= rtx_for_function_call (fndecl
, addr
);
2975 /* Figure out the register where the value, if any, will come back. */
2977 if (TYPE_MODE (TREE_TYPE (exp
)) != VOIDmode
2978 && ! structure_value_addr
)
2980 if (pcc_struct_value
)
2981 valreg
= hard_function_value (build_pointer_type (TREE_TYPE (exp
)),
2982 fndecl
, (pass
== 0));
2984 valreg
= hard_function_value (TREE_TYPE (exp
), fndecl
, (pass
== 0));
2987 /* Precompute all register parameters. It isn't safe to compute anything
2988 once we have started filling any specific hard regs. */
2989 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2991 #ifdef REG_PARM_STACK_SPACE
2992 /* Save the fixed argument area if it's part of the caller's frame and
2993 is clobbered by argument setup for this call. */
2994 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2995 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2996 &low_to_save
, &high_to_save
);
2999 /* Now store (and compute if necessary) all non-register parms.
3000 These come before register parms, since they can require block-moves,
3001 which could clobber the registers used for register parms.
3002 Parms which have partial registers are not stored here,
3003 but we do preallocate space here if they want that. */
3005 for (i
= 0; i
< num_actuals
; i
++)
3006 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
3008 rtx before_arg
= get_last_insn ();
3010 if (store_one_arg (&args
[i
], argblock
, flags
,
3011 adjusted_args_size
.var
!= 0,
3012 reg_parm_stack_space
)
3014 && check_sibcall_argument_overlap (before_arg
,
3016 sibcall_failure
= 1;
3019 /* If we have a parm that is passed in registers but not in memory
3020 and whose alignment does not permit a direct copy into registers,
3021 make a group of pseudos that correspond to each register that we
3023 if (STRICT_ALIGNMENT
)
3024 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
3026 /* Now store any partially-in-registers parm.
3027 This is the last place a block-move can happen. */
3029 for (i
= 0; i
< num_actuals
; i
++)
3030 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
3032 rtx before_arg
= get_last_insn ();
3034 if (store_one_arg (&args
[i
], argblock
, flags
,
3035 adjusted_args_size
.var
!= 0,
3036 reg_parm_stack_space
)
3038 && check_sibcall_argument_overlap (before_arg
,
3040 sibcall_failure
= 1;
3043 /* If we pushed args in forward order, perform stack alignment
3044 after pushing the last arg. */
3045 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
3046 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
3047 - unadjusted_args_size
));
3049 /* If register arguments require space on the stack and stack space
3050 was not preallocated, allocate stack space here for arguments
3051 passed in registers. */
3052 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3053 if (!ACCUMULATE_OUTGOING_ARGS
3054 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
3055 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
3058 /* Pass the function the address in which to return a
3060 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
3062 emit_move_insn (struct_value_rtx
,
3064 force_operand (structure_value_addr
,
3067 if (GET_CODE (struct_value_rtx
) == REG
)
3068 use_reg (&call_fusage
, struct_value_rtx
);
3071 funexp
= prepare_call_address (funexp
, fndecl
, &call_fusage
,
3072 reg_parm_seen
, pass
== 0);
3074 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
3075 pass
== 0, &sibcall_failure
);
3077 /* Perform postincrements before actually calling the function. */
3080 /* Save a pointer to the last insn before the call, so that we can
3081 later safely search backwards to find the CALL_INSN. */
3082 before_call
= get_last_insn ();
3084 /* Set up next argument register. For sibling calls on machines
3085 with register windows this should be the incoming register. */
3086 #ifdef FUNCTION_INCOMING_ARG
3088 next_arg_reg
= FUNCTION_INCOMING_ARG (args_so_far
, VOIDmode
,
3092 next_arg_reg
= FUNCTION_ARG (args_so_far
, VOIDmode
,
3095 /* All arguments and registers used for the call must be set up by
3098 /* Stack must be properly aligned now. */
3099 if (pass
&& stack_pointer_delta
% preferred_unit_stack_boundary
)
3102 /* Generate the actual call instruction. */
3103 emit_call_1 (funexp
, fndecl
, funtype
, unadjusted_args_size
,
3104 adjusted_args_size
.constant
, struct_value_size
,
3105 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
3106 flags
, & args_so_far
);
3108 /* If call is cse'able, make appropriate pair of reg-notes around it.
3109 Test valreg so we don't crash; may safely ignore `const'
3110 if return type is void. Disable for PARALLEL return values, because
3111 we have no way to move such values into a pseudo register. */
3112 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
3116 if (valreg
== 0 || GET_CODE (valreg
) == PARALLEL
)
3118 insns
= get_insns ();
3125 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
3127 /* Mark the return value as a pointer if needed. */
3128 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
3129 mark_reg_pointer (temp
,
3130 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp
))));
3132 /* Construct an "equal form" for the value which mentions all the
3133 arguments in order as well as the function name. */
3134 for (i
= 0; i
< num_actuals
; i
++)
3135 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3136 args
[i
].initial_value
, note
);
3137 note
= gen_rtx_EXPR_LIST (VOIDmode
, funexp
, note
);
3139 insns
= get_insns ();
3142 if (flags
& ECF_PURE
)
3143 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3144 gen_rtx_USE (VOIDmode
,
3145 gen_rtx_MEM (BLKmode
,
3146 gen_rtx_SCRATCH (VOIDmode
))),
3149 emit_libcall_block (insns
, temp
, valreg
, note
);
3154 else if (pass
&& (flags
& ECF_MALLOC
))
3156 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
3159 /* The return value from a malloc-like function is a pointer. */
3160 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
3161 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
3163 emit_move_insn (temp
, valreg
);
3165 /* The return value from a malloc-like function can not alias
3167 last
= get_last_insn ();
3169 gen_rtx_EXPR_LIST (REG_NOALIAS
, temp
, REG_NOTES (last
));
3171 /* Write out the sequence. */
3172 insns
= get_insns ();
3178 /* For calls to `setjmp', etc., inform flow.c it should complain
3179 if nonvolatile values are live. For functions that cannot return,
3180 inform flow that control does not fall through. */
3182 if ((flags
& (ECF_NORETURN
| ECF_LONGJMP
)) || pass
== 0)
3184 /* The barrier must be emitted
3185 immediately after the CALL_INSN. Some ports emit more
3186 than just a CALL_INSN above, so we must search for it here. */
3188 rtx last
= get_last_insn ();
3189 while (GET_CODE (last
) != CALL_INSN
)
3191 last
= PREV_INSN (last
);
3192 /* There was no CALL_INSN? */
3193 if (last
== before_call
)
3197 emit_barrier_after (last
);
3200 if (flags
& ECF_LONGJMP
)
3201 current_function_calls_longjmp
= 1;
3203 /* If this function is returning into a memory location marked as
3204 readonly, it means it is initializing that location. But we normally
3205 treat functions as not clobbering such locations, so we need to
3206 specify that this one does. */
3207 if (target
!= 0 && GET_CODE (target
) == MEM
3208 && structure_value_addr
!= 0 && RTX_UNCHANGING_P (target
))
3209 emit_insn (gen_rtx_CLOBBER (VOIDmode
, target
));
3211 /* If value type not void, return an rtx for the value. */
3213 /* If there are cleanups to be called, don't use a hard reg as target.
3214 We need to double check this and see if it matters anymore. */
3215 if (any_pending_cleanups (1))
3217 if (target
&& REG_P (target
)
3218 && REGNO (target
) < FIRST_PSEUDO_REGISTER
)
3220 sibcall_failure
= 1;
3223 if (TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
3225 target
= const0_rtx
;
3226 else if (structure_value_addr
)
3228 if (target
== 0 || GET_CODE (target
) != MEM
)
3231 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
3232 memory_address (TYPE_MODE (TREE_TYPE (exp
)),
3233 structure_value_addr
));
3234 set_mem_attributes (target
, exp
, 1);
3237 else if (pcc_struct_value
)
3239 /* This is the special C++ case where we need to
3240 know what the true target was. We take care to
3241 never use this value more than once in one expression. */
3242 target
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
3243 copy_to_reg (valreg
));
3244 set_mem_attributes (target
, exp
, 1);
3246 /* Handle calls that return values in multiple non-contiguous locations.
3247 The Irix 6 ABI has examples of this. */
3248 else if (GET_CODE (valreg
) == PARALLEL
)
3252 /* This will only be assigned once, so it can be readonly. */
3253 tree nt
= build_qualified_type (TREE_TYPE (exp
),
3254 (TYPE_QUALS (TREE_TYPE (exp
))
3255 | TYPE_QUAL_CONST
));
3257 target
= assign_temp (nt
, 0, 1, 1);
3258 preserve_temp_slots (target
);
3261 if (! rtx_equal_p (target
, valreg
))
3262 emit_group_store (target
, valreg
,
3263 int_size_in_bytes (TREE_TYPE (exp
)));
3265 /* We can not support sibling calls for this case. */
3266 sibcall_failure
= 1;
3269 && GET_MODE (target
) == TYPE_MODE (TREE_TYPE (exp
))
3270 && GET_MODE (target
) == GET_MODE (valreg
))
3272 /* TARGET and VALREG cannot be equal at this point because the
3273 latter would not have REG_FUNCTION_VALUE_P true, while the
3274 former would if it were referring to the same register.
3276 If they refer to the same register, this move will be a no-op,
3277 except when function inlining is being done. */
3278 emit_move_insn (target
, valreg
);
3280 else if (TYPE_MODE (TREE_TYPE (exp
)) == BLKmode
)
3282 target
= copy_blkmode_from_reg (target
, valreg
, TREE_TYPE (exp
));
3284 /* We can not support sibling calls for this case. */
3285 sibcall_failure
= 1;
3288 target
= copy_to_reg (valreg
);
3290 #ifdef PROMOTE_FUNCTION_RETURN
3291 /* If we promoted this return value, make the proper SUBREG. TARGET
3292 might be const0_rtx here, so be careful. */
3293 if (GET_CODE (target
) == REG
3294 && TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
3295 && GET_MODE (target
) != TYPE_MODE (TREE_TYPE (exp
)))
3297 tree type
= TREE_TYPE (exp
);
3298 int unsignedp
= TREE_UNSIGNED (type
);
3301 /* If we don't promote as expected, something is wrong. */
3302 if (GET_MODE (target
)
3303 != promote_mode (type
, TYPE_MODE (type
), &unsignedp
, 1))
3306 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
3307 && GET_MODE_SIZE (GET_MODE (target
))
3308 > GET_MODE_SIZE (TYPE_MODE (type
)))
3310 offset
= GET_MODE_SIZE (GET_MODE (target
))
3311 - GET_MODE_SIZE (TYPE_MODE (type
));
3312 if (! BYTES_BIG_ENDIAN
)
3313 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
3314 else if (! WORDS_BIG_ENDIAN
)
3315 offset
%= UNITS_PER_WORD
;
3317 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
3318 SUBREG_PROMOTED_VAR_P (target
) = 1;
3319 SUBREG_PROMOTED_UNSIGNED_SET (target
, unsignedp
);
3323 /* If size of args is variable or this was a constructor call for a stack
3324 argument, restore saved stack-pointer value. */
3326 if (old_stack_level
&& ! (flags
& ECF_SP_DEPRESSED
))
3328 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
3329 stack_pointer_delta
= old_stack_pointer_delta
;
3330 pending_stack_adjust
= old_pending_adj
;
3331 stack_arg_under_construction
= old_stack_arg_under_construction
;
3332 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3333 stack_usage_map
= initial_stack_usage_map
;
3334 sibcall_failure
= 1;
3336 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
3338 #ifdef REG_PARM_STACK_SPACE
3340 restore_fixed_argument_area (save_area
, argblock
,
3341 high_to_save
, low_to_save
);
3344 /* If we saved any argument areas, restore them. */
3345 for (i
= 0; i
< num_actuals
; i
++)
3346 if (args
[i
].save_area
)
3348 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
3350 = gen_rtx_MEM (save_mode
,
3351 memory_address (save_mode
,
3352 XEXP (args
[i
].stack_slot
, 0)));
3354 if (save_mode
!= BLKmode
)
3355 emit_move_insn (stack_area
, args
[i
].save_area
);
3357 emit_block_move (stack_area
, args
[i
].save_area
,
3358 GEN_INT (args
[i
].size
.constant
),
3359 BLOCK_OP_CALL_PARM
);
3362 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3363 stack_usage_map
= initial_stack_usage_map
;
3366 /* If this was alloca, record the new stack level for nonlocal gotos.
3367 Check for the handler slots since we might not have a save area
3368 for non-local gotos. */
3370 if ((flags
& ECF_MAY_BE_ALLOCA
) && nonlocal_goto_handler_slots
!= 0)
3371 emit_stack_save (SAVE_NONLOCAL
, &nonlocal_goto_stack_level
, NULL_RTX
);
3373 /* Free up storage we no longer need. */
3374 for (i
= 0; i
< num_actuals
; ++i
)
3375 if (args
[i
].aligned_regs
)
3376 free (args
[i
].aligned_regs
);
3380 /* Undo the fake expand_start_target_temps we did earlier. If
3381 there had been any cleanups created, we've already set
3383 expand_end_target_temps ();
3386 insns
= get_insns ();
3391 tail_call_insns
= insns
;
3393 /* Restore the pending stack adjustment now that we have
3394 finished generating the sibling call sequence. */
3396 pending_stack_adjust
= save_pending_stack_adjust
;
3397 stack_pointer_delta
= save_stack_pointer_delta
;
3399 /* Prepare arg structure for next iteration. */
3400 for (i
= 0; i
< num_actuals
; i
++)
3403 args
[i
].aligned_regs
= 0;
3407 sbitmap_free (stored_args_map
);
3411 normal_call_insns
= insns
;
3413 /* Verify that we've deallocated all the stack we used. */
3414 if (old_stack_allocated
!=
3415 stack_pointer_delta
- pending_stack_adjust
)
3419 /* If something prevents making this a sibling call,
3420 zero out the sequence. */
3421 if (sibcall_failure
)
3422 tail_call_insns
= NULL_RTX
;
3425 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3426 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3427 can happen if the arguments to this function call an inline
3428 function who's expansion contains another CALL_PLACEHOLDER.
3430 If there are any C_Ps in any of these sequences, replace them
3431 with their normal call. */
3433 for (insn
= normal_call_insns
; insn
; insn
= NEXT_INSN (insn
))
3434 if (GET_CODE (insn
) == CALL_INSN
3435 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3436 replace_call_placeholder (insn
, sibcall_use_normal
);
3438 for (insn
= tail_call_insns
; insn
; insn
= NEXT_INSN (insn
))
3439 if (GET_CODE (insn
) == CALL_INSN
3440 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3441 replace_call_placeholder (insn
, sibcall_use_normal
);
3443 for (insn
= tail_recursion_insns
; insn
; insn
= NEXT_INSN (insn
))
3444 if (GET_CODE (insn
) == CALL_INSN
3445 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3446 replace_call_placeholder (insn
, sibcall_use_normal
);
3448 /* If this was a potential tail recursion site, then emit a
3449 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3450 One of them will be selected later. */
3451 if (tail_recursion_insns
|| tail_call_insns
)
3453 /* The tail recursion label must be kept around. We could expose
3454 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3455 and makes determining true tail recursion sites difficult.
3457 So we set LABEL_PRESERVE_P here, then clear it when we select
3458 one of the call sequences after rtl generation is complete. */
3459 if (tail_recursion_insns
)
3460 LABEL_PRESERVE_P (tail_recursion_label
) = 1;
3461 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode
, normal_call_insns
,
3463 tail_recursion_insns
,
3464 tail_recursion_label
));
3467 emit_insn (normal_call_insns
);
3469 currently_expanding_call
--;
3471 /* If this function returns with the stack pointer depressed, ensure
3472 this block saves and restores the stack pointer, show it was
3473 changed, and adjust for any outgoing arg space. */
3474 if (flags
& ECF_SP_DEPRESSED
)
3476 clear_pending_stack_adjust ();
3477 emit_insn (gen_rtx (CLOBBER
, VOIDmode
, stack_pointer_rtx
));
3478 emit_move_insn (virtual_stack_dynamic_rtx
, stack_pointer_rtx
);
3479 save_stack_pointer ();
3485 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3486 The RETVAL parameter specifies whether return value needs to be saved, other
3487 parameters are documented in the emit_library_call function below. */
3490 emit_library_call_value_1 (retval
, orgfun
, value
, fn_type
, outmode
, nargs
, p
)
3494 enum libcall_type fn_type
;
3495 enum machine_mode outmode
;
3499 /* Total size in bytes of all the stack-parms scanned so far. */
3500 struct args_size args_size
;
3501 /* Size of arguments before any adjustments (such as rounding). */
3502 struct args_size original_args_size
;
3507 struct args_size alignment_pad
;
3509 CUMULATIVE_ARGS args_so_far
;
3513 enum machine_mode mode
;
3516 struct args_size offset
;
3517 struct args_size size
;
3521 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3522 rtx call_fusage
= 0;
3525 int pcc_struct_value
= 0;
3526 int struct_value_size
= 0;
3528 int reg_parm_stack_space
= 0;
3531 tree tfom
; /* type_for_mode (outmode, 0) */
3533 #ifdef REG_PARM_STACK_SPACE
3534 /* Define the boundary of the register parm stack space that needs to be
3536 int low_to_save
, high_to_save
;
3537 rtx save_area
= 0; /* Place that it is saved. */
3540 /* Size of the stack reserved for parameter registers. */
3541 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3542 char *initial_stack_usage_map
= stack_usage_map
;
3544 #ifdef REG_PARM_STACK_SPACE
3545 #ifdef MAYBE_REG_PARM_STACK_SPACE
3546 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
3548 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3552 /* By default, library functions can not throw. */
3553 flags
= ECF_NOTHROW
;
3565 case LCT_CONST_MAKE_BLOCK
:
3566 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
3568 case LCT_PURE_MAKE_BLOCK
:
3569 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
3572 flags
|= ECF_NORETURN
;
3575 flags
= ECF_NORETURN
;
3577 case LCT_ALWAYS_RETURN
:
3578 flags
= ECF_ALWAYS_RETURN
;
3580 case LCT_RETURNS_TWICE
:
3581 flags
= ECF_RETURNS_TWICE
;
3586 /* Ensure current function's preferred stack boundary is at least
3588 if (cfun
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3589 cfun
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3591 /* If this kind of value comes back in memory,
3592 decide where in memory it should come back. */
3593 if (outmode
!= VOIDmode
)
3595 tfom
= (*lang_hooks
.types
.type_for_mode
) (outmode
, 0);
3596 if (aggregate_value_p (tfom
))
3598 #ifdef PCC_STATIC_STRUCT_RETURN
3600 = hard_function_value (build_pointer_type (tfom
), 0, 0);
3601 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3602 pcc_struct_value
= 1;
3604 value
= gen_reg_rtx (outmode
);
3605 #else /* not PCC_STATIC_STRUCT_RETURN */
3606 struct_value_size
= GET_MODE_SIZE (outmode
);
3607 if (value
!= 0 && GET_CODE (value
) == MEM
)
3610 mem_value
= assign_temp (tfom
, 0, 1, 1);
3612 /* This call returns a big structure. */
3613 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3617 tfom
= void_type_node
;
3619 /* ??? Unfinished: must pass the memory address as an argument. */
3621 /* Copy all the libcall-arguments out of the varargs data
3622 and into a vector ARGVEC.
3624 Compute how to pass each argument. We only support a very small subset
3625 of the full argument passing conventions to limit complexity here since
3626 library functions shouldn't have many args. */
3628 argvec
= (struct arg
*) alloca ((nargs
+ 1) * sizeof (struct arg
));
3629 memset ((char *) argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3631 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3632 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3634 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0);
3637 args_size
.constant
= 0;
3642 /* Now we are about to start emitting insns that can be deleted
3643 if a libcall is deleted. */
3644 if (flags
& ECF_LIBCALL_BLOCK
)
3649 /* If there's a structure value address to be passed,
3650 either pass it in the special place, or pass it as an extra argument. */
3651 if (mem_value
&& struct_value_rtx
== 0 && ! pcc_struct_value
)
3653 rtx addr
= XEXP (mem_value
, 0);
3656 /* Make sure it is a reasonable operand for a move or push insn. */
3657 if (GET_CODE (addr
) != REG
&& GET_CODE (addr
) != MEM
3658 && ! (CONSTANT_P (addr
) && LEGITIMATE_CONSTANT_P (addr
)))
3659 addr
= force_operand (addr
, NULL_RTX
);
3661 argvec
[count
].value
= addr
;
3662 argvec
[count
].mode
= Pmode
;
3663 argvec
[count
].partial
= 0;
3665 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, Pmode
, NULL_TREE
, 1);
3666 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3667 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, Pmode
, NULL_TREE
, 1))
3671 locate_and_pad_parm (Pmode
, NULL_TREE
,
3672 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3675 argvec
[count
].reg
!= 0,
3677 NULL_TREE
, &args_size
, &argvec
[count
].offset
,
3678 &argvec
[count
].size
, &alignment_pad
);
3680 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3681 || reg_parm_stack_space
> 0)
3682 args_size
.constant
+= argvec
[count
].size
.constant
;
3684 FUNCTION_ARG_ADVANCE (args_so_far
, Pmode
, (tree
) 0, 1);
3689 for (; count
< nargs
; count
++)
3691 rtx val
= va_arg (p
, rtx
);
3692 enum machine_mode mode
= va_arg (p
, enum machine_mode
);
3694 /* We cannot convert the arg value to the mode the library wants here;
3695 must do it earlier where we know the signedness of the arg. */
3697 || (GET_MODE (val
) != mode
&& GET_MODE (val
) != VOIDmode
))
3700 /* On some machines, there's no way to pass a float to a library fcn.
3701 Pass it as a double instead. */
3702 #ifdef LIBGCC_NEEDS_DOUBLE
3703 if (LIBGCC_NEEDS_DOUBLE
&& mode
== SFmode
)
3704 val
= convert_modes (DFmode
, SFmode
, val
, 0), mode
= DFmode
;
3707 /* There's no need to call protect_from_queue, because
3708 either emit_move_insn or emit_push_insn will do that. */
3710 /* Make sure it is a reasonable operand for a move or push insn. */
3711 if (GET_CODE (val
) != REG
&& GET_CODE (val
) != MEM
3712 && ! (CONSTANT_P (val
) && LEGITIMATE_CONSTANT_P (val
)))
3713 val
= force_operand (val
, NULL_RTX
);
3715 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3716 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far
, mode
, NULL_TREE
, 1))
3720 #ifdef FUNCTION_ARG_CALLEE_COPIES
3721 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far
, mode
,
3726 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3727 functions, so we have to pretend this isn't such a function. */
3728 if (flags
& ECF_LIBCALL_BLOCK
)
3730 rtx insns
= get_insns ();
3734 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3736 /* If this was a CONST function, it is now PURE since
3737 it now reads memory. */
3738 if (flags
& ECF_CONST
)
3740 flags
&= ~ECF_CONST
;
3744 if (GET_MODE (val
) == MEM
&& ! must_copy
)
3748 slot
= assign_temp ((*lang_hooks
.types
.type_for_mode
) (mode
, 0),
3750 emit_move_insn (slot
, val
);
3754 tree type
= (*lang_hooks
.types
.type_for_mode
) (mode
, 0);
3757 = gen_rtx_MEM (mode
,
3758 expand_expr (build1 (ADDR_EXPR
,
3759 build_pointer_type (type
),
3760 make_tree (type
, val
)),
3761 NULL_RTX
, VOIDmode
, 0));
3764 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3765 gen_rtx_USE (VOIDmode
, slot
),
3768 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3769 gen_rtx_CLOBBER (VOIDmode
,
3774 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3778 argvec
[count
].value
= val
;
3779 argvec
[count
].mode
= mode
;
3781 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, mode
, NULL_TREE
, 1);
3783 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3784 argvec
[count
].partial
3785 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, mode
, NULL_TREE
, 1);
3787 argvec
[count
].partial
= 0;
3790 locate_and_pad_parm (mode
, NULL_TREE
,
3791 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3794 argvec
[count
].reg
!= 0,
3796 NULL_TREE
, &args_size
, &argvec
[count
].offset
,
3797 &argvec
[count
].size
, &alignment_pad
);
3799 if (argvec
[count
].size
.var
)
3802 if (reg_parm_stack_space
== 0 && argvec
[count
].partial
)
3803 argvec
[count
].size
.constant
-= argvec
[count
].partial
* UNITS_PER_WORD
;
3805 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3806 || reg_parm_stack_space
> 0)
3807 args_size
.constant
+= argvec
[count
].size
.constant
;
3809 FUNCTION_ARG_ADVANCE (args_so_far
, mode
, (tree
) 0, 1);
3812 #ifdef FINAL_REG_PARM_STACK_SPACE
3813 reg_parm_stack_space
= FINAL_REG_PARM_STACK_SPACE (args_size
.constant
,
3816 /* If this machine requires an external definition for library
3817 functions, write one out. */
3818 assemble_external_libcall (fun
);
3820 original_args_size
= args_size
;
3821 args_size
.constant
= (((args_size
.constant
3822 + stack_pointer_delta
3826 - stack_pointer_delta
);
3828 args_size
.constant
= MAX (args_size
.constant
,
3829 reg_parm_stack_space
);
3831 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3832 args_size
.constant
-= reg_parm_stack_space
;
3835 if (args_size
.constant
> current_function_outgoing_args_size
)
3836 current_function_outgoing_args_size
= args_size
.constant
;
3838 if (ACCUMULATE_OUTGOING_ARGS
)
3840 /* Since the stack pointer will never be pushed, it is possible for
3841 the evaluation of a parm to clobber something we have already
3842 written to the stack. Since most function calls on RISC machines
3843 do not use the stack, this is uncommon, but must work correctly.
3845 Therefore, we save any area of the stack that was already written
3846 and that we are using. Here we set up to do this by making a new
3847 stack usage map from the old one.
3849 Another approach might be to try to reorder the argument
3850 evaluations to avoid this conflicting stack usage. */
3852 needed
= args_size
.constant
;
3854 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3855 /* Since we will be writing into the entire argument area, the
3856 map must be allocated for its entire size, not just the part that
3857 is the responsibility of the caller. */
3858 needed
+= reg_parm_stack_space
;
3861 #ifdef ARGS_GROW_DOWNWARD
3862 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3865 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3868 stack_usage_map
= (char *) alloca (highest_outgoing_arg_in_use
);
3870 if (initial_highest_arg_in_use
)
3871 memcpy (stack_usage_map
, initial_stack_usage_map
,
3872 initial_highest_arg_in_use
);
3874 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3875 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3876 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3879 /* We must be careful to use virtual regs before they're instantiated,
3880 and real regs afterwards. Loop optimization, for example, can create
3881 new libcalls after we've instantiated the virtual regs, and if we
3882 use virtuals anyway, they won't match the rtl patterns. */
3884 if (virtuals_instantiated
)
3885 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3887 argblock
= virtual_outgoing_args_rtx
;
3892 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3895 /* If we push args individually in reverse order, perform stack alignment
3896 before the first push (the last arg). */
3897 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3898 anti_adjust_stack (GEN_INT (args_size
.constant
3899 - original_args_size
.constant
));
3901 if (PUSH_ARGS_REVERSED
)
3912 #ifdef REG_PARM_STACK_SPACE
3913 if (ACCUMULATE_OUTGOING_ARGS
)
3915 /* The argument list is the property of the called routine and it
3916 may clobber it. If the fixed area has been used for previous
3917 parameters, we must save and restore it. */
3918 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
3919 &low_to_save
, &high_to_save
);
3923 /* Push the args that need to be pushed. */
3925 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3926 are to be pushed. */
3927 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3929 enum machine_mode mode
= argvec
[argnum
].mode
;
3930 rtx val
= argvec
[argnum
].value
;
3931 rtx reg
= argvec
[argnum
].reg
;
3932 int partial
= argvec
[argnum
].partial
;
3933 int lower_bound
= 0, upper_bound
= 0, i
;
3935 if (! (reg
!= 0 && partial
== 0))
3937 if (ACCUMULATE_OUTGOING_ARGS
)
3939 /* If this is being stored into a pre-allocated, fixed-size,
3940 stack area, save any previous data at that location. */
3942 #ifdef ARGS_GROW_DOWNWARD
3943 /* stack_slot is negative, but we want to index stack_usage_map
3944 with positive values. */
3945 upper_bound
= -argvec
[argnum
].offset
.constant
+ 1;
3946 lower_bound
= upper_bound
- argvec
[argnum
].size
.constant
;
3948 lower_bound
= argvec
[argnum
].offset
.constant
;
3949 upper_bound
= lower_bound
+ argvec
[argnum
].size
.constant
;
3953 /* Don't worry about things in the fixed argument area;
3954 it has already been saved. */
3955 if (i
< reg_parm_stack_space
)
3956 i
= reg_parm_stack_space
;
3957 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
3960 if (i
< upper_bound
)
3962 /* We need to make a save area. See what mode we can make
3964 enum machine_mode save_mode
3965 = mode_for_size (argvec
[argnum
].size
.constant
3973 plus_constant (argblock
,
3974 argvec
[argnum
].offset
.constant
)));
3975 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3977 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3981 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, PARM_BOUNDARY
,
3982 partial
, reg
, 0, argblock
,
3983 GEN_INT (argvec
[argnum
].offset
.constant
),
3984 reg_parm_stack_space
, ARGS_SIZE_RTX (alignment_pad
));
3986 /* Now mark the segment we just used. */
3987 if (ACCUMULATE_OUTGOING_ARGS
)
3988 for (i
= lower_bound
; i
< upper_bound
; i
++)
3989 stack_usage_map
[i
] = 1;
3995 /* If we pushed args in forward order, perform stack alignment
3996 after pushing the last arg. */
3997 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3998 anti_adjust_stack (GEN_INT (args_size
.constant
3999 - original_args_size
.constant
));
4001 if (PUSH_ARGS_REVERSED
)
4006 fun
= prepare_call_address (fun
, NULL_TREE
, &call_fusage
, 0, 0);
4008 /* Now load any reg parms into their regs. */
4010 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4011 are to be pushed. */
4012 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
4014 rtx val
= argvec
[argnum
].value
;
4015 rtx reg
= argvec
[argnum
].reg
;
4016 int partial
= argvec
[argnum
].partial
;
4018 /* Handle calls that pass values in multiple non-contiguous
4019 locations. The PA64 has examples of this for library calls. */
4020 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
4021 emit_group_load (reg
, val
, GET_MODE_SIZE (GET_MODE (val
)));
4022 else if (reg
!= 0 && partial
== 0)
4023 emit_move_insn (reg
, val
);
4028 /* Any regs containing parms remain in use through the call. */
4029 for (count
= 0; count
< nargs
; count
++)
4031 rtx reg
= argvec
[count
].reg
;
4032 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
4033 use_group_regs (&call_fusage
, reg
);
4035 use_reg (&call_fusage
, reg
);
4038 /* Pass the function the address in which to return a structure value. */
4039 if (mem_value
!= 0 && struct_value_rtx
!= 0 && ! pcc_struct_value
)
4041 emit_move_insn (struct_value_rtx
,
4043 force_operand (XEXP (mem_value
, 0),
4045 if (GET_CODE (struct_value_rtx
) == REG
)
4046 use_reg (&call_fusage
, struct_value_rtx
);
4049 /* Don't allow popping to be deferred, since then
4050 cse'ing of library calls could delete a call and leave the pop. */
4052 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
4053 ? hard_libcall_value (outmode
) : NULL_RTX
);
4055 /* Stack must be properly aligned now. */
4056 if (stack_pointer_delta
& (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1))
4059 before_call
= get_last_insn ();
4061 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4062 will set inhibit_defer_pop to that value. */
4063 /* The return type is needed to decide how many bytes the function pops.
4064 Signedness plays no role in that, so for simplicity, we pretend it's
4065 always signed. We also assume that the list of arguments passed has
4066 no impact, so we pretend it is unknown. */
4069 get_identifier (XSTR (orgfun
, 0)),
4070 build_function_type (tfom
, NULL_TREE
),
4071 original_args_size
.constant
, args_size
.constant
,
4073 FUNCTION_ARG (args_so_far
, VOIDmode
, void_type_node
, 1),
4075 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, & args_so_far
);
4077 /* For calls to `setjmp', etc., inform flow.c it should complain
4078 if nonvolatile values are live. For functions that cannot return,
4079 inform flow that control does not fall through. */
4081 if (flags
& (ECF_NORETURN
| ECF_LONGJMP
))
4083 /* The barrier note must be emitted
4084 immediately after the CALL_INSN. Some ports emit more than
4085 just a CALL_INSN above, so we must search for it here. */
4087 rtx last
= get_last_insn ();
4088 while (GET_CODE (last
) != CALL_INSN
)
4090 last
= PREV_INSN (last
);
4091 /* There was no CALL_INSN? */
4092 if (last
== before_call
)
4096 emit_barrier_after (last
);
4099 /* Now restore inhibit_defer_pop to its actual original value. */
4102 /* If call is cse'able, make appropriate pair of reg-notes around it.
4103 Test valreg so we don't crash; may safely ignore `const'
4104 if return type is void. Disable for PARALLEL return values, because
4105 we have no way to move such values into a pseudo register. */
4106 if (flags
& ECF_LIBCALL_BLOCK
)
4112 insns
= get_insns ();
4122 if (GET_CODE (valreg
) == PARALLEL
)
4124 temp
= gen_reg_rtx (outmode
);
4125 emit_group_store (temp
, valreg
, outmode
);
4129 temp
= gen_reg_rtx (GET_MODE (valreg
));
4131 /* Construct an "equal form" for the value which mentions all the
4132 arguments in order as well as the function name. */
4133 for (i
= 0; i
< nargs
; i
++)
4134 note
= gen_rtx_EXPR_LIST (VOIDmode
, argvec
[i
].value
, note
);
4135 note
= gen_rtx_EXPR_LIST (VOIDmode
, fun
, note
);
4137 insns
= get_insns ();
4140 if (flags
& ECF_PURE
)
4141 note
= gen_rtx_EXPR_LIST (VOIDmode
,
4142 gen_rtx_USE (VOIDmode
,
4143 gen_rtx_MEM (BLKmode
,
4144 gen_rtx_SCRATCH (VOIDmode
))),
4147 emit_libcall_block (insns
, temp
, valreg
, note
);
4154 /* Copy the value to the right place. */
4155 if (outmode
!= VOIDmode
&& retval
)
4161 if (value
!= mem_value
)
4162 emit_move_insn (value
, mem_value
);
4164 else if (GET_CODE (valreg
) == PARALLEL
)
4167 value
= gen_reg_rtx (outmode
);
4168 emit_group_store (value
, valreg
, outmode
);
4170 else if (value
!= 0)
4171 emit_move_insn (value
, valreg
);
4176 if (ACCUMULATE_OUTGOING_ARGS
)
4178 #ifdef REG_PARM_STACK_SPACE
4180 restore_fixed_argument_area (save_area
, argblock
,
4181 high_to_save
, low_to_save
);
4184 /* If we saved any argument areas, restore them. */
4185 for (count
= 0; count
< nargs
; count
++)
4186 if (argvec
[count
].save_area
)
4188 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
4190 = gen_rtx_MEM (save_mode
,
4193 plus_constant (argblock
,
4194 argvec
[count
].offset
.constant
)));
4196 emit_move_insn (stack_area
, argvec
[count
].save_area
);
4199 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4200 stack_usage_map
= initial_stack_usage_map
;
4207 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4208 (emitting the queue unless NO_QUEUE is nonzero),
4209 for a value of mode OUTMODE,
4210 with NARGS different arguments, passed as alternating rtx values
4211 and machine_modes to convert them to.
4212 The rtx values should have been passed through protect_from_queue already.
4214 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4215 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4216 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4217 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4218 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4219 or other LCT_ value for other types of library calls. */
4222 emit_library_call
VPARAMS((rtx orgfun
, enum libcall_type fn_type
,
4223 enum machine_mode outmode
, int nargs
, ...))
4226 VA_FIXEDARG (p
, rtx
, orgfun
);
4227 VA_FIXEDARG (p
, int, fn_type
);
4228 VA_FIXEDARG (p
, enum machine_mode
, outmode
);
4229 VA_FIXEDARG (p
, int, nargs
);
4231 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
4236 /* Like emit_library_call except that an extra argument, VALUE,
4237 comes second and says where to store the result.
4238 (If VALUE is zero, this function chooses a convenient way
4239 to return the value.
4241 This function returns an rtx for where the value is to be found.
4242 If VALUE is nonzero, VALUE is returned. */
4245 emit_library_call_value
VPARAMS((rtx orgfun
, rtx value
,
4246 enum libcall_type fn_type
,
4247 enum machine_mode outmode
, int nargs
, ...))
4252 VA_FIXEDARG (p
, rtx
, orgfun
);
4253 VA_FIXEDARG (p
, rtx
, value
);
4254 VA_FIXEDARG (p
, int, fn_type
);
4255 VA_FIXEDARG (p
, enum machine_mode
, outmode
);
4256 VA_FIXEDARG (p
, int, nargs
);
4258 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
4266 /* Store a single argument for a function call
4267 into the register or memory area where it must be passed.
4268 *ARG describes the argument value and where to pass it.
4270 ARGBLOCK is the address of the stack-block for all the arguments,
4271 or 0 on a machine where arguments are pushed individually.
4273 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4274 so must be careful about how the stack is used.
4276 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4277 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4278 that we need not worry about saving and restoring the stack.
4280 FNDECL is the declaration of the function we are calling.
4282 Return nonzero if this arg should cause sibcall failure,
4286 store_one_arg (arg
, argblock
, flags
, variable_size
, reg_parm_stack_space
)
4287 struct arg_data
*arg
;
4290 int variable_size ATTRIBUTE_UNUSED
;
4291 int reg_parm_stack_space
;
4293 tree pval
= arg
->tree_value
;
4297 int i
, lower_bound
= 0, upper_bound
= 0;
4298 int sibcall_failure
= 0;
4300 if (TREE_CODE (pval
) == ERROR_MARK
)
4303 /* Push a new temporary level for any temporaries we make for
4307 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4309 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4310 save any previous data at that location. */
4311 if (argblock
&& ! variable_size
&& arg
->stack
)
4313 #ifdef ARGS_GROW_DOWNWARD
4314 /* stack_slot is negative, but we want to index stack_usage_map
4315 with positive values. */
4316 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4317 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4321 lower_bound
= upper_bound
- arg
->size
.constant
;
4323 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4324 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4328 upper_bound
= lower_bound
+ arg
->size
.constant
;
4332 /* Don't worry about things in the fixed argument area;
4333 it has already been saved. */
4334 if (i
< reg_parm_stack_space
)
4335 i
= reg_parm_stack_space
;
4336 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
4339 if (i
< upper_bound
)
4341 /* We need to make a save area. See what mode we can make it. */
4342 enum machine_mode save_mode
4343 = mode_for_size (arg
->size
.constant
* BITS_PER_UNIT
, MODE_INT
, 1);
4345 = gen_rtx_MEM (save_mode
,
4346 memory_address (save_mode
,
4347 XEXP (arg
->stack_slot
, 0)));
4349 if (save_mode
== BLKmode
)
4351 tree ot
= TREE_TYPE (arg
->tree_value
);
4352 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4353 | TYPE_QUAL_CONST
));
4355 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4356 preserve_temp_slots (arg
->save_area
);
4357 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4358 expr_size (arg
->tree_value
),
4359 BLOCK_OP_CALL_PARM
);
4363 arg
->save_area
= gen_reg_rtx (save_mode
);
4364 emit_move_insn (arg
->save_area
, stack_area
);
4370 /* If this isn't going to be placed on both the stack and in registers,
4371 set up the register and number of words. */
4372 if (! arg
->pass_on_stack
)
4374 if (flags
& ECF_SIBCALL
)
4375 reg
= arg
->tail_call_reg
;
4378 partial
= arg
->partial
;
4381 if (reg
!= 0 && partial
== 0)
4382 /* Being passed entirely in a register. We shouldn't be called in
4386 /* If this arg needs special alignment, don't load the registers
4388 if (arg
->n_aligned_regs
!= 0)
4391 /* If this is being passed partially in a register, we can't evaluate
4392 it directly into its stack slot. Otherwise, we can. */
4393 if (arg
->value
== 0)
4395 /* stack_arg_under_construction is nonzero if a function argument is
4396 being evaluated directly into the outgoing argument list and
4397 expand_call must take special action to preserve the argument list
4398 if it is called recursively.
4400 For scalar function arguments stack_usage_map is sufficient to
4401 determine which stack slots must be saved and restored. Scalar
4402 arguments in general have pass_on_stack == 0.
4404 If this argument is initialized by a function which takes the
4405 address of the argument (a C++ constructor or a C function
4406 returning a BLKmode structure), then stack_usage_map is
4407 insufficient and expand_call must push the stack around the
4408 function call. Such arguments have pass_on_stack == 1.
4410 Note that it is always safe to set stack_arg_under_construction,
4411 but this generates suboptimal code if set when not needed. */
4413 if (arg
->pass_on_stack
)
4414 stack_arg_under_construction
++;
4416 arg
->value
= expand_expr (pval
,
4418 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4419 ? NULL_RTX
: arg
->stack
,
4420 VOIDmode
, EXPAND_STACK_PARM
);
4422 /* If we are promoting object (or for any other reason) the mode
4423 doesn't agree, convert the mode. */
4425 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4426 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4427 arg
->value
, arg
->unsignedp
);
4429 if (arg
->pass_on_stack
)
4430 stack_arg_under_construction
--;
4433 /* Don't allow anything left on stack from computation
4434 of argument to alloca. */
4435 if (flags
& ECF_MAY_BE_ALLOCA
)
4436 do_pending_stack_adjust ();
4438 if (arg
->value
== arg
->stack
)
4439 /* If the value is already in the stack slot, we are done. */
4441 else if (arg
->mode
!= BLKmode
)
4445 /* Argument is a scalar, not entirely passed in registers.
4446 (If part is passed in registers, arg->partial says how much
4447 and emit_push_insn will take care of putting it there.)
4449 Push it, and if its size is less than the
4450 amount of space allocated to it,
4451 also bump stack pointer by the additional space.
4452 Note that in C the default argument promotions
4453 will prevent such mismatches. */
4455 size
= GET_MODE_SIZE (arg
->mode
);
4456 /* Compute how much space the push instruction will push.
4457 On many machines, pushing a byte will advance the stack
4458 pointer by a halfword. */
4459 #ifdef PUSH_ROUNDING
4460 size
= PUSH_ROUNDING (size
);
4464 /* Compute how much space the argument should get:
4465 round up to a multiple of the alignment for arguments. */
4466 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4467 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4468 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4469 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4471 /* This isn't already where we want it on the stack, so put it there.
4472 This can either be done with push or copy insns. */
4473 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
,
4474 PARM_BOUNDARY
, partial
, reg
, used
- size
, argblock
,
4475 ARGS_SIZE_RTX (arg
->offset
), reg_parm_stack_space
,
4476 ARGS_SIZE_RTX (arg
->alignment_pad
));
4478 /* Unless this is a partially-in-register argument, the argument is now
4481 arg
->value
= arg
->stack
;
4485 /* BLKmode, at least partly to be pushed. */
4487 unsigned int parm_align
;
4491 /* Pushing a nonscalar.
4492 If part is passed in registers, PARTIAL says how much
4493 and emit_push_insn will take care of putting it there. */
4495 /* Round its size up to a multiple
4496 of the allocation unit for arguments. */
4498 if (arg
->size
.var
!= 0)
4501 size_rtx
= ARGS_SIZE_RTX (arg
->size
);
4505 /* PUSH_ROUNDING has no effect on us, because
4506 emit_push_insn for BLKmode is careful to avoid it. */
4507 excess
= (arg
->size
.constant
- int_size_in_bytes (TREE_TYPE (pval
))
4508 + partial
* UNITS_PER_WORD
);
4509 size_rtx
= expand_expr (size_in_bytes (TREE_TYPE (pval
)),
4510 NULL_RTX
, TYPE_MODE (sizetype
), 0);
4513 /* Some types will require stricter alignment, which will be
4514 provided for elsewhere in argument layout. */
4515 parm_align
= MAX (PARM_BOUNDARY
, TYPE_ALIGN (TREE_TYPE (pval
)));
4517 /* When an argument is padded down, the block is aligned to
4518 PARM_BOUNDARY, but the actual argument isn't. */
4519 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4522 parm_align
= BITS_PER_UNIT
;
4525 unsigned int excess_align
= (excess
& -excess
) * BITS_PER_UNIT
;
4526 parm_align
= MIN (parm_align
, excess_align
);
4530 if ((flags
& ECF_SIBCALL
) && GET_CODE (arg
->value
) == MEM
)
4532 /* emit_push_insn might not work properly if arg->value and
4533 argblock + arg->offset areas overlap. */
4537 if (XEXP (x
, 0) == current_function_internal_arg_pointer
4538 || (GET_CODE (XEXP (x
, 0)) == PLUS
4539 && XEXP (XEXP (x
, 0), 0) ==
4540 current_function_internal_arg_pointer
4541 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
))
4543 if (XEXP (x
, 0) != current_function_internal_arg_pointer
)
4544 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4546 /* expand_call should ensure this */
4547 if (arg
->offset
.var
|| GET_CODE (size_rtx
) != CONST_INT
)
4550 if (arg
->offset
.constant
> i
)
4552 if (arg
->offset
.constant
< i
+ INTVAL (size_rtx
))
4553 sibcall_failure
= 1;
4555 else if (arg
->offset
.constant
< i
)
4557 if (i
< arg
->offset
.constant
+ INTVAL (size_rtx
))
4558 sibcall_failure
= 1;
4563 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4564 parm_align
, partial
, reg
, excess
, argblock
,
4565 ARGS_SIZE_RTX (arg
->offset
), reg_parm_stack_space
,
4566 ARGS_SIZE_RTX (arg
->alignment_pad
));
4568 /* Unless this is a partially-in-register argument, the argument is now
4571 ??? Unlike the case above, in which we want the actual
4572 address of the data, so that we can load it directly into a
4573 register, here we want the address of the stack slot, so that
4574 it's properly aligned for word-by-word copying or something
4575 like that. It's not clear that this is always correct. */
4577 arg
->value
= arg
->stack_slot
;
4580 /* Mark all slots this store used. */
4581 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
4582 && argblock
&& ! variable_size
&& arg
->stack
)
4583 for (i
= lower_bound
; i
< upper_bound
; i
++)
4584 stack_usage_map
[i
] = 1;
4586 /* Once we have pushed something, pops can't safely
4587 be deferred during the rest of the arguments. */
4590 /* ANSI doesn't require a sequence point here,
4591 but PCC has one, so this will avoid some problems. */
4594 /* Free any temporary slots made in processing this argument. Show
4595 that we might have taken the address of something and pushed that
4597 preserve_temp_slots (NULL_RTX
);
4601 return sibcall_failure
;
4604 /* Nonzero if we do not know how to pass TYPE solely in registers.
4605 We cannot do so in the following cases:
4607 - if the type has variable size
4608 - if the type is marked as addressable (it is required to be constructed
4610 - if the padding and mode of the type is such that a copy into a register
4611 would put it into the wrong part of the register.
4613 Which padding can't be supported depends on the byte endianness.
4615 A value in a register is implicitly padded at the most significant end.
4616 On a big-endian machine, that is the lower end in memory.
4617 So a value padded in memory at the upper end can't go in a register.
4618 For a little-endian machine, the reverse is true. */
4621 default_must_pass_in_stack (mode
, type
)
4622 enum machine_mode mode
;
4628 /* If the type has variable size... */
4629 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4632 /* If the type is marked as addressable (it is required
4633 to be constructed into the stack)... */
4634 if (TREE_ADDRESSABLE (type
))
4637 /* If the padding and mode of the type is such that a copy into
4638 a register would put it into the wrong part of the register. */
4640 && int_size_in_bytes (type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
4641 && (FUNCTION_ARG_PADDING (mode
, type
)
4642 == (BYTES_BIG_ENDIAN
? upward
: downward
)))