1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998
3 1999, 2000, 2001 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
37 #if !defined FUNCTION_OK_FOR_SIBCALL
38 #define FUNCTION_OK_FOR_SIBCALL(DECL) 1
41 /* Decide whether a function's arguments should be processed
42 from first to last or from last to first.
44 They should if the stack and args grow in opposite directions, but
45 only if we have push insns. */
49 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
50 #define PUSH_ARGS_REVERSED PUSH_ARGS
55 #ifndef PUSH_ARGS_REVERSED
56 #define PUSH_ARGS_REVERSED 0
59 #ifndef STACK_POINTER_OFFSET
60 #define STACK_POINTER_OFFSET 0
63 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
64 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
66 /* Data structure and subroutines used within expand_call. */
70 /* Tree node for this argument. */
72 /* Mode for value; TYPE_MODE unless promoted. */
73 enum machine_mode mode
;
74 /* Current RTL value for argument, or 0 if it isn't precomputed. */
76 /* Initially-compute RTL value for argument; only for const functions. */
78 /* Register to pass this argument in, 0 if passed on stack, or an
79 PARALLEL if the arg is to be copied into multiple non-contiguous
82 /* Register to pass this argument in when generating tail call sequence.
83 This is not the same register as for normal calls on machines with
86 /* If REG was promoted from the actual mode of the argument expression,
87 indicates whether the promotion is sign- or zero-extended. */
89 /* Number of registers to use. 0 means put the whole arg in registers.
90 Also 0 if not passed in registers. */
92 /* Non-zero if argument must be passed on stack.
93 Note that some arguments may be passed on the stack
94 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
95 pass_on_stack identifies arguments that *cannot* go in registers. */
97 /* Offset of this argument from beginning of stack-args. */
98 struct args_size offset
;
99 /* Similar, but offset to the start of the stack slot. Different from
100 OFFSET if this arg pads downward. */
101 struct args_size slot_offset
;
102 /* Size of this argument on the stack, rounded up for any padding it gets,
103 parts of the argument passed in registers do not count.
104 If REG_PARM_STACK_SPACE is defined, then register parms
105 are counted here as well. */
106 struct args_size size
;
107 /* Location on the stack at which parameter should be stored. The store
108 has already been done if STACK == VALUE. */
110 /* Location on the stack of the start of this argument slot. This can
111 differ from STACK if this arg pads downward. This location is known
112 to be aligned to FUNCTION_ARG_BOUNDARY. */
114 /* Place that this stack area has been saved, if needed. */
116 /* If an argument's alignment does not permit direct copying into registers,
117 copy in smaller-sized pieces into pseudos. These are stored in a
118 block pointed to by this field. The next field says how many
119 word-sized pseudos we made. */
122 /* The amount that the stack pointer needs to be adjusted to
123 force alignment for the next argument. */
124 struct args_size alignment_pad
;
127 /* A vector of one char per byte of stack space. A byte if non-zero if
128 the corresponding stack location has been used.
129 This vector is used to prevent a function call within an argument from
130 clobbering any stack already set up. */
131 static char *stack_usage_map
;
133 /* Size of STACK_USAGE_MAP. */
134 static int highest_outgoing_arg_in_use
;
136 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
137 stack location's tail call argument has been already stored into the stack.
138 This bitmap is used to prevent sibling call optimization if function tries
139 to use parent's incoming argument slots when they have been already
140 overwritten with tail call arguments. */
141 static sbitmap stored_args_map
;
143 /* stack_arg_under_construction is nonzero when an argument may be
144 initialized with a constructor call (including a C function that
145 returns a BLKmode struct) and expand_call must take special action
146 to make sure the object being constructed does not overlap the
147 argument list for the constructor call. */
148 int stack_arg_under_construction
;
150 static int calls_function
PARAMS ((tree
, int));
151 static int calls_function_1
PARAMS ((tree
, int));
153 /* Nonzero if this is a call to a `const' function. */
155 /* Nonzero if this is a call to a `volatile' function. */
156 #define ECF_NORETURN 2
157 /* Nonzero if this is a call to malloc or a related function. */
159 /* Nonzero if it is plausible that this is a call to alloca. */
160 #define ECF_MAY_BE_ALLOCA 8
161 /* Nonzero if this is a call to a function that won't throw an exception. */
162 #define ECF_NOTHROW 16
163 /* Nonzero if this is a call to setjmp or a related function. */
164 #define ECF_RETURNS_TWICE 32
165 /* Nonzero if this is a call to `longjmp'. */
166 #define ECF_LONGJMP 64
167 /* Nonzero if this is a syscall that makes a new process in the image of
169 #define ECF_FORK_OR_EXEC 128
170 #define ECF_SIBCALL 256
171 /* Nonzero if this is a call to "pure" function (like const function,
172 but may read memory. */
174 /* Nonzero if this is a call to a function that returns with the stack
175 pointer depressed. */
176 #define ECF_SP_DEPRESSED 1024
177 /* Nonzero if this call is known to always return. */
178 #define ECF_ALWAYS_RETURN 2048
180 static void emit_call_1
PARAMS ((rtx
, tree
, tree
, HOST_WIDE_INT
,
181 HOST_WIDE_INT
, HOST_WIDE_INT
, rtx
,
182 rtx
, int, rtx
, int));
183 static void precompute_register_parameters
PARAMS ((int,
186 static int store_one_arg
PARAMS ((struct arg_data
*, rtx
, int, int,
188 static void store_unaligned_arguments_into_pseudos
PARAMS ((struct arg_data
*,
190 static int finalize_must_preallocate
PARAMS ((int, int,
192 struct args_size
*));
193 static void precompute_arguments
PARAMS ((int, int,
195 static int compute_argument_block_size
PARAMS ((int,
198 static void initialize_argument_information
PARAMS ((int,
205 static void compute_argument_addresses
PARAMS ((struct arg_data
*,
207 static rtx rtx_for_function_call
PARAMS ((tree
, tree
));
208 static void load_register_parameters
PARAMS ((struct arg_data
*,
210 static rtx emit_library_call_value_1
PARAMS ((int, rtx
, rtx
,
214 static int special_function_p
PARAMS ((tree
, int));
215 static int flags_from_decl_or_type
PARAMS ((tree
));
216 static rtx try_to_integrate
PARAMS ((tree
, tree
, rtx
,
218 static int check_sibcall_argument_overlap_1
PARAMS ((rtx
));
219 static int check_sibcall_argument_overlap
PARAMS ((rtx
, struct arg_data
*));
221 static int combine_pending_stack_adjustment_and_call
222 PARAMS ((int, struct args_size
*, int));
224 #ifdef REG_PARM_STACK_SPACE
225 static rtx save_fixed_argument_area
PARAMS ((int, rtx
, int *, int *));
226 static void restore_fixed_argument_area
PARAMS ((rtx
, rtx
, int, int));
229 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
232 If WHICH is 0, return 1 if EXP contains a call to any function.
233 Actually, we only need return 1 if evaluating EXP would require pushing
234 arguments on the stack, but that is too difficult to compute, so we just
235 assume any function call might require the stack. */
237 static tree calls_function_save_exprs
;
240 calls_function (exp
, which
)
246 calls_function_save_exprs
= 0;
247 val
= calls_function_1 (exp
, which
);
248 calls_function_save_exprs
= 0;
252 /* Recursive function to do the work of above function. */
255 calls_function_1 (exp
, which
)
260 enum tree_code code
= TREE_CODE (exp
);
261 int class = TREE_CODE_CLASS (code
);
262 int length
= first_rtl_op (code
);
264 /* If this code is language-specific, we don't know what it will do. */
265 if ((int) code
>= NUM_TREE_CODES
)
273 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp
, 0))))
275 && (TYPE_RETURNS_STACK_DEPRESSED
276 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp
, 0))))))
278 else if (TREE_CODE (TREE_OPERAND (exp
, 0)) == ADDR_EXPR
279 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0))
281 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0),
283 & ECF_MAY_BE_ALLOCA
))
292 for (tem
= CONSTRUCTOR_ELTS (exp
); tem
!= 0; tem
= TREE_CHAIN (tem
))
293 if (calls_function_1 (TREE_VALUE (tem
), which
))
300 if (SAVE_EXPR_RTL (exp
) != 0)
302 if (value_member (exp
, calls_function_save_exprs
))
304 calls_function_save_exprs
= tree_cons (NULL_TREE
, exp
,
305 calls_function_save_exprs
);
306 return (TREE_OPERAND (exp
, 0) != 0
307 && calls_function_1 (TREE_OPERAND (exp
, 0), which
));
314 for (local
= BLOCK_VARS (exp
); local
; local
= TREE_CHAIN (local
))
315 if (DECL_INITIAL (local
) != 0
316 && calls_function_1 (DECL_INITIAL (local
), which
))
319 for (subblock
= BLOCK_SUBBLOCKS (exp
);
321 subblock
= TREE_CHAIN (subblock
))
322 if (calls_function_1 (subblock
, which
))
328 for (; exp
!= 0; exp
= TREE_CHAIN (exp
))
329 if (calls_function_1 (TREE_VALUE (exp
), which
))
337 /* Only expressions, references, and blocks can contain calls. */
338 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
341 for (i
= 0; i
< length
; i
++)
342 if (TREE_OPERAND (exp
, i
) != 0
343 && calls_function_1 (TREE_OPERAND (exp
, i
), which
))
349 /* Force FUNEXP into a form suitable for the address of a CALL,
350 and return that as an rtx. Also load the static chain register
351 if FNDECL is a nested function.
353 CALL_FUSAGE points to a variable holding the prospective
354 CALL_INSN_FUNCTION_USAGE information. */
357 prepare_call_address (funexp
, fndecl
, call_fusage
, reg_parm_seen
, sibcallp
)
364 rtx static_chain_value
= 0;
366 funexp
= protect_from_queue (funexp
, 0);
369 /* Get possible static chain value for nested function in C. */
370 static_chain_value
= lookup_static_chain (fndecl
);
372 /* Make a valid memory address and copy constants thru pseudo-regs,
373 but not for a constant address if -fno-function-cse. */
374 if (GET_CODE (funexp
) != SYMBOL_REF
)
375 /* If we are using registers for parameters, force the
376 function address into a register now. */
377 funexp
= ((SMALL_REGISTER_CLASSES
&& reg_parm_seen
)
378 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
379 : memory_address (FUNCTION_MODE
, funexp
));
382 #ifndef NO_FUNCTION_CSE
383 if (optimize
&& ! flag_no_function_cse
)
384 #ifdef NO_RECURSIVE_FUNCTION_CSE
385 if (fndecl
!= current_function_decl
)
387 funexp
= force_reg (Pmode
, funexp
);
391 if (static_chain_value
!= 0)
393 emit_move_insn (static_chain_rtx
, static_chain_value
);
395 if (GET_CODE (static_chain_rtx
) == REG
)
396 use_reg (call_fusage
, static_chain_rtx
);
402 /* Generate instructions to call function FUNEXP,
403 and optionally pop the results.
404 The CALL_INSN is the first insn generated.
406 FNDECL is the declaration node of the function. This is given to the
407 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
409 FUNTYPE is the data type of the function. This is given to the macro
410 RETURN_POPS_ARGS to determine whether this function pops its own args.
411 We used to allow an identifier for library functions, but that doesn't
412 work when the return type is an aggregate type and the calling convention
413 says that the pointer to this aggregate is to be popped by the callee.
415 STACK_SIZE is the number of bytes of arguments on the stack,
416 ROUNDED_STACK_SIZE is that number rounded up to
417 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
418 both to put into the call insn and to generate explicit popping
421 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
422 It is zero if this call doesn't want a structure value.
424 NEXT_ARG_REG is the rtx that results from executing
425 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
426 just after all the args have had their registers assigned.
427 This could be whatever you like, but normally it is the first
428 arg-register beyond those used for args in this call,
429 or 0 if all the arg-registers are used in this call.
430 It is passed on to `gen_call' so you can put this info in the call insn.
432 VALREG is a hard register in which a value is returned,
433 or 0 if the call does not return a value.
435 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
436 the args to this call were processed.
437 We restore `inhibit_defer_pop' to that value.
439 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
440 denote registers used by the called function. */
443 emit_call_1 (funexp
, fndecl
, funtype
, stack_size
, rounded_stack_size
,
444 struct_value_size
, next_arg_reg
, valreg
, old_inhibit_defer_pop
,
445 call_fusage
, ecf_flags
)
447 tree fndecl ATTRIBUTE_UNUSED
;
448 tree funtype ATTRIBUTE_UNUSED
;
449 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED
;
450 HOST_WIDE_INT rounded_stack_size
;
451 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED
;
452 rtx next_arg_reg ATTRIBUTE_UNUSED
;
454 int old_inhibit_defer_pop
;
458 rtx rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
460 int already_popped
= 0;
461 HOST_WIDE_INT n_popped
= RETURN_POPS_ARGS (fndecl
, funtype
, stack_size
);
462 #if defined (HAVE_call) && defined (HAVE_call_value)
463 rtx struct_value_size_rtx
;
464 struct_value_size_rtx
= GEN_INT (struct_value_size
);
467 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
468 and we don't want to load it into a register as an optimization,
469 because prepare_call_address already did it if it should be done. */
470 if (GET_CODE (funexp
) != SYMBOL_REF
)
471 funexp
= memory_address (FUNCTION_MODE
, funexp
);
473 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
474 if ((ecf_flags
& ECF_SIBCALL
)
475 && HAVE_sibcall_pop
&& HAVE_sibcall_value_pop
476 && (n_popped
> 0 || stack_size
== 0))
478 rtx n_pop
= GEN_INT (n_popped
);
481 /* If this subroutine pops its own args, record that in the call insn
482 if possible, for the sake of frame pointer elimination. */
485 pat
= GEN_SIBCALL_VALUE_POP (valreg
,
486 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
487 rounded_stack_size_rtx
, next_arg_reg
,
490 pat
= GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
491 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
493 emit_call_insn (pat
);
499 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
500 /* If the target has "call" or "call_value" insns, then prefer them
501 if no arguments are actually popped. If the target does not have
502 "call" or "call_value" insns, then we must use the popping versions
503 even if the call has no arguments to pop. */
504 #if defined (HAVE_call) && defined (HAVE_call_value)
505 if (HAVE_call
&& HAVE_call_value
&& HAVE_call_pop
&& HAVE_call_value_pop
506 && n_popped
> 0 && ! (ecf_flags
& ECF_SP_DEPRESSED
))
508 if (HAVE_call_pop
&& HAVE_call_value_pop
)
511 rtx n_pop
= GEN_INT (n_popped
);
514 /* If this subroutine pops its own args, record that in the call insn
515 if possible, for the sake of frame pointer elimination. */
518 pat
= GEN_CALL_VALUE_POP (valreg
,
519 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
520 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
522 pat
= GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
523 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
525 emit_call_insn (pat
);
531 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
532 if ((ecf_flags
& ECF_SIBCALL
)
533 && HAVE_sibcall
&& HAVE_sibcall_value
)
536 emit_call_insn (GEN_SIBCALL_VALUE (valreg
,
537 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
538 rounded_stack_size_rtx
,
539 next_arg_reg
, NULL_RTX
));
541 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
542 rounded_stack_size_rtx
, next_arg_reg
,
543 struct_value_size_rtx
));
548 #if defined (HAVE_call) && defined (HAVE_call_value)
549 if (HAVE_call
&& HAVE_call_value
)
552 emit_call_insn (GEN_CALL_VALUE (valreg
,
553 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
554 rounded_stack_size_rtx
, next_arg_reg
,
557 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
558 rounded_stack_size_rtx
, next_arg_reg
,
559 struct_value_size_rtx
));
565 /* Find the CALL insn we just emitted. */
566 for (call_insn
= get_last_insn ();
567 call_insn
&& GET_CODE (call_insn
) != CALL_INSN
;
568 call_insn
= PREV_INSN (call_insn
))
574 /* Mark memory as used for "pure" function call. */
575 if (ecf_flags
& ECF_PURE
)
579 gen_rtx_USE (VOIDmode
,
580 gen_rtx_MEM (BLKmode
, gen_rtx_SCRATCH (VOIDmode
))),
583 /* Put the register usage information on the CALL. If there is already
584 some usage information, put ours at the end. */
585 if (CALL_INSN_FUNCTION_USAGE (call_insn
))
589 for (link
= CALL_INSN_FUNCTION_USAGE (call_insn
); XEXP (link
, 1) != 0;
590 link
= XEXP (link
, 1))
593 XEXP (link
, 1) = call_fusage
;
596 CALL_INSN_FUNCTION_USAGE (call_insn
) = call_fusage
;
598 /* If this is a const call, then set the insn's unchanging bit. */
599 if (ecf_flags
& (ECF_CONST
| ECF_PURE
))
600 CONST_OR_PURE_CALL_P (call_insn
) = 1;
602 /* If this call can't throw, attach a REG_EH_REGION reg note to that
604 if (ecf_flags
& ECF_NOTHROW
)
605 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_EH_REGION
, const0_rtx
,
606 REG_NOTES (call_insn
));
608 if (ecf_flags
& ECF_NORETURN
)
609 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_NORETURN
, const0_rtx
,
610 REG_NOTES (call_insn
));
611 if (ecf_flags
& ECF_ALWAYS_RETURN
)
612 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN
, const0_rtx
,
613 REG_NOTES (call_insn
));
615 if (ecf_flags
& ECF_RETURNS_TWICE
)
617 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_SETJMP
, const0_rtx
,
618 REG_NOTES (call_insn
));
619 current_function_calls_setjmp
= 1;
622 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
624 /* Restore this now, so that we do defer pops for this call's args
625 if the context of the call as a whole permits. */
626 inhibit_defer_pop
= old_inhibit_defer_pop
;
631 CALL_INSN_FUNCTION_USAGE (call_insn
)
632 = gen_rtx_EXPR_LIST (VOIDmode
,
633 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
634 CALL_INSN_FUNCTION_USAGE (call_insn
));
635 rounded_stack_size
-= n_popped
;
636 rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
637 stack_pointer_delta
-= n_popped
;
640 if (!ACCUMULATE_OUTGOING_ARGS
)
642 /* If returning from the subroutine does not automatically pop the args,
643 we need an instruction to pop them sooner or later.
644 Perhaps do it now; perhaps just record how much space to pop later.
646 If returning from the subroutine does pop the args, indicate that the
647 stack pointer will be changed. */
649 if (rounded_stack_size
!= 0 && ! (ecf_flags
& ECF_SP_DEPRESSED
))
651 if (flag_defer_pop
&& inhibit_defer_pop
== 0
652 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
653 pending_stack_adjust
+= rounded_stack_size
;
655 adjust_stack (rounded_stack_size_rtx
);
658 /* When we accumulate outgoing args, we must avoid any stack manipulations.
659 Restore the stack pointer to its original value now. Usually
660 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
661 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
662 popping variants of functions exist as well.
664 ??? We may optimize similar to defer_pop above, but it is
665 probably not worthwhile.
667 ??? It will be worthwhile to enable combine_stack_adjustments even for
670 anti_adjust_stack (GEN_INT (n_popped
));
673 /* Determine if the function identified by NAME and FNDECL is one with
674 special properties we wish to know about.
676 For example, if the function might return more than one time (setjmp), then
677 set RETURNS_TWICE to a nonzero value.
679 Similarly set LONGJMP for if the function is in the longjmp family.
681 Set MALLOC for any of the standard memory allocation functions which
682 allocate from the heap.
684 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
685 space from the stack such as alloca. */
688 special_function_p (fndecl
, flags
)
692 if (! (flags
& ECF_MALLOC
)
693 && fndecl
&& DECL_NAME (fndecl
)
694 && IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) <= 17
695 /* Exclude functions not at the file scope, or not `extern',
696 since they are not the magic functions we would otherwise
698 && DECL_CONTEXT (fndecl
) == NULL_TREE
&& TREE_PUBLIC (fndecl
))
700 const char *name
= IDENTIFIER_POINTER (DECL_NAME (fndecl
));
701 const char *tname
= name
;
703 /* We assume that alloca will always be called by name. It
704 makes no sense to pass it as a pointer-to-function to
705 anything that does not understand its behavior. */
706 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 6
708 && ! strcmp (name
, "alloca"))
709 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 16
711 && ! strcmp (name
, "__builtin_alloca"))))
712 flags
|= ECF_MAY_BE_ALLOCA
;
714 /* Disregard prefix _, __ or __x. */
717 if (name
[1] == '_' && name
[2] == 'x')
719 else if (name
[1] == '_')
728 && (! strcmp (tname
, "setjmp")
729 || ! strcmp (tname
, "setjmp_syscall")))
731 && ! strcmp (tname
, "sigsetjmp"))
733 && ! strcmp (tname
, "savectx")))
734 flags
|= ECF_RETURNS_TWICE
;
737 && ! strcmp (tname
, "siglongjmp"))
738 flags
|= ECF_LONGJMP
;
740 else if ((tname
[0] == 'q' && tname
[1] == 's'
741 && ! strcmp (tname
, "qsetjmp"))
742 || (tname
[0] == 'v' && tname
[1] == 'f'
743 && ! strcmp (tname
, "vfork")))
744 flags
|= ECF_RETURNS_TWICE
;
746 else if (tname
[0] == 'l' && tname
[1] == 'o'
747 && ! strcmp (tname
, "longjmp"))
748 flags
|= ECF_LONGJMP
;
750 else if ((tname
[0] == 'f' && tname
[1] == 'o'
751 && ! strcmp (tname
, "fork"))
752 /* Linux specific: __clone. check NAME to insist on the
753 leading underscores, to avoid polluting the ISO / POSIX
755 || (name
[0] == '_' && name
[1] == '_'
756 && ! strcmp (tname
, "clone"))
757 || (tname
[0] == 'e' && tname
[1] == 'x' && tname
[2] == 'e'
758 && tname
[3] == 'c' && (tname
[4] == 'l' || tname
[4] == 'v')
760 || ((tname
[5] == 'p' || tname
[5] == 'e')
761 && tname
[6] == '\0'))))
762 flags
|= ECF_FORK_OR_EXEC
;
764 /* Do not add any more malloc-like functions to this list,
765 instead mark them as malloc functions using the malloc attribute.
766 Note, realloc is not suitable for attribute malloc since
767 it may return the same address across multiple calls.
768 C++ operator new is not suitable because it is not required
769 to return a unique pointer; indeed, the standard placement new
770 just returns its argument. */
771 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl
))) == Pmode
772 && (! strcmp (tname
, "malloc")
773 || ! strcmp (tname
, "calloc")
774 || ! strcmp (tname
, "strdup")))
780 /* Return nonzero when tree represent call to longjmp. */
783 setjmp_call_p (fndecl
)
786 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
789 /* Detect flags (function attributes) from the function type node. */
792 flags_from_decl_or_type (exp
)
797 /* ??? We can't set IS_MALLOC for function types? */
800 /* The function exp may have the `malloc' attribute. */
801 if (DECL_P (exp
) && DECL_IS_MALLOC (exp
))
804 /* The function exp may have the `pure' attribute. */
805 if (DECL_P (exp
) && DECL_IS_PURE (exp
))
808 if (TREE_NOTHROW (exp
))
809 flags
|= ECF_NOTHROW
;
812 if (TREE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
815 if (TREE_THIS_VOLATILE (exp
))
816 flags
|= ECF_NORETURN
;
821 /* Precompute all register parameters as described by ARGS, storing values
822 into fields within the ARGS array.
824 NUM_ACTUALS indicates the total number elements in the ARGS array.
826 Set REG_PARM_SEEN if we encounter a register parameter. */
829 precompute_register_parameters (num_actuals
, args
, reg_parm_seen
)
831 struct arg_data
*args
;
838 for (i
= 0; i
< num_actuals
; i
++)
839 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
843 if (args
[i
].value
== 0)
846 args
[i
].value
= expand_expr (args
[i
].tree_value
, NULL_RTX
,
848 preserve_temp_slots (args
[i
].value
);
851 /* ANSI doesn't require a sequence point here,
852 but PCC has one, so this will avoid some problems. */
856 /* If we are to promote the function arg to a wider mode,
859 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
861 = convert_modes (args
[i
].mode
,
862 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
863 args
[i
].value
, args
[i
].unsignedp
);
865 /* If the value is expensive, and we are inside an appropriately
866 short loop, put the value into a pseudo and then put the pseudo
869 For small register classes, also do this if this call uses
870 register parameters. This is to avoid reload conflicts while
871 loading the parameters registers. */
873 if ((! (GET_CODE (args
[i
].value
) == REG
874 || (GET_CODE (args
[i
].value
) == SUBREG
875 && GET_CODE (SUBREG_REG (args
[i
].value
)) == REG
)))
876 && args
[i
].mode
!= BLKmode
877 && rtx_cost (args
[i
].value
, SET
) > COSTS_N_INSNS (1)
878 && ((SMALL_REGISTER_CLASSES
&& *reg_parm_seen
)
879 || preserve_subexpressions_p ()))
880 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
884 #ifdef REG_PARM_STACK_SPACE
886 /* The argument list is the property of the called routine and it
887 may clobber it. If the fixed area has been used for previous
888 parameters, we must save and restore it. */
891 save_fixed_argument_area (reg_parm_stack_space
, argblock
,
892 low_to_save
, high_to_save
)
893 int reg_parm_stack_space
;
899 rtx save_area
= NULL_RTX
;
901 /* Compute the boundary of the that needs to be saved, if any. */
902 #ifdef ARGS_GROW_DOWNWARD
903 for (i
= 0; i
< reg_parm_stack_space
+ 1; i
++)
905 for (i
= 0; i
< reg_parm_stack_space
; i
++)
908 if (i
>= highest_outgoing_arg_in_use
909 || stack_usage_map
[i
] == 0)
912 if (*low_to_save
== -1)
918 if (*low_to_save
>= 0)
920 int num_to_save
= *high_to_save
- *low_to_save
+ 1;
921 enum machine_mode save_mode
922 = mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
925 /* If we don't have the required alignment, must do this in BLKmode. */
926 if ((*low_to_save
& (MIN (GET_MODE_SIZE (save_mode
),
927 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
930 #ifdef ARGS_GROW_DOWNWARD
932 = gen_rtx_MEM (save_mode
,
933 memory_address (save_mode
,
934 plus_constant (argblock
,
937 stack_area
= gen_rtx_MEM (save_mode
,
938 memory_address (save_mode
,
939 plus_constant (argblock
,
943 set_mem_align (stack_area
, PARM_BOUNDARY
);
944 if (save_mode
== BLKmode
)
946 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
947 /* Cannot use emit_block_move here because it can be done by a
948 library call which in turn gets into this place again and deadly
949 infinite recursion happens. */
950 move_by_pieces (validize_mem (save_area
), stack_area
, num_to_save
,
955 save_area
= gen_reg_rtx (save_mode
);
956 emit_move_insn (save_area
, stack_area
);
964 restore_fixed_argument_area (save_area
, argblock
, high_to_save
, low_to_save
)
970 enum machine_mode save_mode
= GET_MODE (save_area
);
971 #ifdef ARGS_GROW_DOWNWARD
973 = gen_rtx_MEM (save_mode
,
974 memory_address (save_mode
,
975 plus_constant (argblock
,
979 = gen_rtx_MEM (save_mode
,
980 memory_address (save_mode
,
981 plus_constant (argblock
,
985 if (save_mode
!= BLKmode
)
986 emit_move_insn (stack_area
, save_area
);
988 /* Cannot use emit_block_move here because it can be done by a library
989 call which in turn gets into this place again and deadly infinite
990 recursion happens. */
991 move_by_pieces (stack_area
, validize_mem (save_area
),
992 high_to_save
- low_to_save
+ 1, PARM_BOUNDARY
);
994 #endif /* REG_PARM_STACK_SPACE */
996 /* If any elements in ARGS refer to parameters that are to be passed in
997 registers, but not in memory, and whose alignment does not permit a
998 direct copy into registers. Copy the values into a group of pseudos
999 which we will later copy into the appropriate hard registers.
1001 Pseudos for each unaligned argument will be stored into the array
1002 args[argnum].aligned_regs. The caller is responsible for deallocating
1003 the aligned_regs array if it is nonzero. */
1006 store_unaligned_arguments_into_pseudos (args
, num_actuals
)
1007 struct arg_data
*args
;
1012 for (i
= 0; i
< num_actuals
; i
++)
1013 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
1014 && args
[i
].mode
== BLKmode
1015 && (TYPE_ALIGN (TREE_TYPE (args
[i
].tree_value
))
1016 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
1018 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1019 int big_endian_correction
= 0;
1021 args
[i
].n_aligned_regs
1022 = args
[i
].partial
? args
[i
].partial
1023 : (bytes
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1025 args
[i
].aligned_regs
= (rtx
*) xmalloc (sizeof (rtx
)
1026 * args
[i
].n_aligned_regs
);
1028 /* Structures smaller than a word are aligned to the least
1029 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1030 this means we must skip the empty high order bytes when
1031 calculating the bit offset. */
1032 if (BYTES_BIG_ENDIAN
1033 && !FUNCTION_ARG_REG_LITTLE_ENDIAN
1034 && bytes
< UNITS_PER_WORD
)
1035 big_endian_correction
= (BITS_PER_WORD
- (bytes
* BITS_PER_UNIT
));
1037 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1039 rtx reg
= gen_reg_rtx (word_mode
);
1040 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
1041 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
1043 args
[i
].aligned_regs
[j
] = reg
;
1045 /* There is no need to restrict this code to loading items
1046 in TYPE_ALIGN sized hunks. The bitfield instructions can
1047 load up entire word sized registers efficiently.
1049 ??? This may not be needed anymore.
1050 We use to emit a clobber here but that doesn't let later
1051 passes optimize the instructions we emit. By storing 0 into
1052 the register later passes know the first AND to zero out the
1053 bitfield being set in the register is unnecessary. The store
1054 of 0 will be deleted as will at least the first AND. */
1056 emit_move_insn (reg
, const0_rtx
);
1058 bytes
-= bitsize
/ BITS_PER_UNIT
;
1059 store_bit_field (reg
, bitsize
, big_endian_correction
, word_mode
,
1060 extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
1061 word_mode
, word_mode
,
1068 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1071 NUM_ACTUALS is the total number of parameters.
1073 N_NAMED_ARGS is the total number of named arguments.
1075 FNDECL is the tree code for the target of this call (if known)
1077 ARGS_SO_FAR holds state needed by the target to know where to place
1080 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1081 for arguments which are passed in registers.
1083 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1084 and may be modified by this routine.
1086 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1087 flags which may may be modified by this routine. */
1090 initialize_argument_information (num_actuals
, args
, args_size
, n_named_args
,
1091 actparms
, fndecl
, args_so_far
,
1092 reg_parm_stack_space
, old_stack_level
,
1093 old_pending_adj
, must_preallocate
,
1095 int num_actuals ATTRIBUTE_UNUSED
;
1096 struct arg_data
*args
;
1097 struct args_size
*args_size
;
1098 int n_named_args ATTRIBUTE_UNUSED
;
1101 CUMULATIVE_ARGS
*args_so_far
;
1102 int reg_parm_stack_space
;
1103 rtx
*old_stack_level
;
1104 int *old_pending_adj
;
1105 int *must_preallocate
;
1108 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1111 /* Count arg position in order args appear. */
1114 struct args_size alignment_pad
;
1118 args_size
->constant
= 0;
1121 /* In this loop, we consider args in the order they are written.
1122 We fill up ARGS from the front or from the back if necessary
1123 so that in any case the first arg to be pushed ends up at the front. */
1125 if (PUSH_ARGS_REVERSED
)
1127 i
= num_actuals
- 1, inc
= -1;
1128 /* In this case, must reverse order of args
1129 so that we compute and push the last arg first. */
1136 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1137 for (p
= actparms
, argpos
= 0; p
; p
= TREE_CHAIN (p
), i
+= inc
, argpos
++)
1139 tree type
= TREE_TYPE (TREE_VALUE (p
));
1141 enum machine_mode mode
;
1143 args
[i
].tree_value
= TREE_VALUE (p
);
1145 /* Replace erroneous argument with constant zero. */
1146 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1147 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1149 /* If TYPE is a transparent union, pass things the way we would
1150 pass the first field of the union. We have already verified that
1151 the modes are the same. */
1152 if (TREE_CODE (type
) == UNION_TYPE
&& TYPE_TRANSPARENT_UNION (type
))
1153 type
= TREE_TYPE (TYPE_FIELDS (type
));
1155 /* Decide where to pass this arg.
1157 args[i].reg is nonzero if all or part is passed in registers.
1159 args[i].partial is nonzero if part but not all is passed in registers,
1160 and the exact value says how many words are passed in registers.
1162 args[i].pass_on_stack is nonzero if the argument must at least be
1163 computed on the stack. It may then be loaded back into registers
1164 if args[i].reg is nonzero.
1166 These decisions are driven by the FUNCTION_... macros and must agree
1167 with those made by function.c. */
1169 /* See if this argument should be passed by invisible reference. */
1170 if ((TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1171 && contains_placeholder_p (TYPE_SIZE (type
)))
1172 || TREE_ADDRESSABLE (type
)
1173 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1174 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far
, TYPE_MODE (type
),
1175 type
, argpos
< n_named_args
)
1179 /* If we're compiling a thunk, pass through invisible
1180 references instead of making a copy. */
1181 if (current_function_is_thunk
1182 #ifdef FUNCTION_ARG_CALLEE_COPIES
1183 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far
, TYPE_MODE (type
),
1184 type
, argpos
< n_named_args
)
1185 /* If it's in a register, we must make a copy of it too. */
1186 /* ??? Is this a sufficient test? Is there a better one? */
1187 && !(TREE_CODE (args
[i
].tree_value
) == VAR_DECL
1188 && REG_P (DECL_RTL (args
[i
].tree_value
)))
1189 && ! TREE_ADDRESSABLE (type
))
1193 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1194 new object from the argument. If we are passing by
1195 invisible reference, the callee will do that for us, so we
1196 can strip off the TARGET_EXPR. This is not always safe,
1197 but it is safe in the only case where this is a useful
1198 optimization; namely, when the argument is a plain object.
1199 In that case, the frontend is just asking the backend to
1200 make a bitwise copy of the argument. */
1202 if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1203 && (DECL_P (TREE_OPERAND (args
[i
].tree_value
, 1)))
1204 && ! REG_P (DECL_RTL (TREE_OPERAND (args
[i
].tree_value
, 1))))
1205 args
[i
].tree_value
= TREE_OPERAND (args
[i
].tree_value
, 1);
1207 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1208 build_pointer_type (type
),
1209 args
[i
].tree_value
);
1210 type
= build_pointer_type (type
);
1214 /* We make a copy of the object and pass the address to the
1215 function being called. */
1218 if (!COMPLETE_TYPE_P (type
)
1219 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1220 || (flag_stack_check
&& ! STACK_CHECK_BUILTIN
1221 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type
),
1222 STACK_CHECK_MAX_VAR_SIZE
))))
1224 /* This is a variable-sized object. Make space on the stack
1226 rtx size_rtx
= expr_size (TREE_VALUE (p
));
1228 if (*old_stack_level
== 0)
1230 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1231 *old_pending_adj
= pending_stack_adjust
;
1232 pending_stack_adjust
= 0;
1235 copy
= gen_rtx_MEM (BLKmode
,
1236 allocate_dynamic_stack_space
1237 (size_rtx
, NULL_RTX
, TYPE_ALIGN (type
)));
1238 set_mem_attributes (copy
, type
, 1);
1241 copy
= assign_temp (type
, 0, 1, 0);
1243 store_expr (args
[i
].tree_value
, copy
, 0);
1244 *ecf_flags
&= ~(ECF_CONST
| ECF_PURE
);
1246 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1247 build_pointer_type (type
),
1248 make_tree (type
, copy
));
1249 type
= build_pointer_type (type
);
1253 mode
= TYPE_MODE (type
);
1254 unsignedp
= TREE_UNSIGNED (type
);
1256 #ifdef PROMOTE_FUNCTION_ARGS
1257 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
1260 args
[i
].unsignedp
= unsignedp
;
1261 args
[i
].mode
= mode
;
1263 args
[i
].reg
= FUNCTION_ARG (*args_so_far
, mode
, type
,
1264 argpos
< n_named_args
);
1265 #ifdef FUNCTION_INCOMING_ARG
1266 /* If this is a sibling call and the machine has register windows, the
1267 register window has to be unwinded before calling the routine, so
1268 arguments have to go into the incoming registers. */
1269 args
[i
].tail_call_reg
= FUNCTION_INCOMING_ARG (*args_so_far
, mode
, type
,
1270 argpos
< n_named_args
);
1272 args
[i
].tail_call_reg
= args
[i
].reg
;
1275 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1278 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far
, mode
, type
,
1279 argpos
< n_named_args
);
1282 args
[i
].pass_on_stack
= MUST_PASS_IN_STACK (mode
, type
);
1284 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1285 it means that we are to pass this arg in the register(s) designated
1286 by the PARALLEL, but also to pass it in the stack. */
1287 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1288 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1289 args
[i
].pass_on_stack
= 1;
1291 /* If this is an addressable type, we must preallocate the stack
1292 since we must evaluate the object into its final location.
1294 If this is to be passed in both registers and the stack, it is simpler
1296 if (TREE_ADDRESSABLE (type
)
1297 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1298 *must_preallocate
= 1;
1300 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1301 we cannot consider this function call constant. */
1302 if (TREE_ADDRESSABLE (type
))
1303 *ecf_flags
&= ~(ECF_CONST
| ECF_PURE
);
1305 /* Compute the stack-size of this argument. */
1306 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1307 || reg_parm_stack_space
> 0
1308 || args
[i
].pass_on_stack
)
1309 locate_and_pad_parm (mode
, type
,
1310 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1315 fndecl
, args_size
, &args
[i
].offset
,
1316 &args
[i
].size
, &alignment_pad
);
1318 #ifndef ARGS_GROW_DOWNWARD
1319 args
[i
].slot_offset
= *args_size
;
1322 args
[i
].alignment_pad
= alignment_pad
;
1324 /* If a part of the arg was put into registers,
1325 don't include that part in the amount pushed. */
1326 if (reg_parm_stack_space
== 0 && ! args
[i
].pass_on_stack
)
1327 args
[i
].size
.constant
-= ((args
[i
].partial
* UNITS_PER_WORD
)
1328 / (PARM_BOUNDARY
/ BITS_PER_UNIT
)
1329 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
1331 /* Update ARGS_SIZE, the total stack space for args so far. */
1333 args_size
->constant
+= args
[i
].size
.constant
;
1334 if (args
[i
].size
.var
)
1336 ADD_PARM_SIZE (*args_size
, args
[i
].size
.var
);
1339 /* Since the slot offset points to the bottom of the slot,
1340 we must record it after incrementing if the args grow down. */
1341 #ifdef ARGS_GROW_DOWNWARD
1342 args
[i
].slot_offset
= *args_size
;
1344 args
[i
].slot_offset
.constant
= -args_size
->constant
;
1346 SUB_PARM_SIZE (args
[i
].slot_offset
, args_size
->var
);
1349 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1350 have been used, etc. */
1352 FUNCTION_ARG_ADVANCE (*args_so_far
, TYPE_MODE (type
), type
,
1353 argpos
< n_named_args
);
1357 /* Update ARGS_SIZE to contain the total size for the argument block.
1358 Return the original constant component of the argument block's size.
1360 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1361 for arguments passed in registers. */
1364 compute_argument_block_size (reg_parm_stack_space
, args_size
,
1365 preferred_stack_boundary
)
1366 int reg_parm_stack_space
;
1367 struct args_size
*args_size
;
1368 int preferred_stack_boundary ATTRIBUTE_UNUSED
;
1370 int unadjusted_args_size
= args_size
->constant
;
1372 /* For accumulate outgoing args mode we don't need to align, since the frame
1373 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1374 backends from generating misaligned frame sizes. */
1375 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1376 preferred_stack_boundary
= STACK_BOUNDARY
;
1378 /* Compute the actual size of the argument block required. The variable
1379 and constant sizes must be combined, the size may have to be rounded,
1380 and there may be a minimum required size. */
1384 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1385 args_size
->constant
= 0;
1387 preferred_stack_boundary
/= BITS_PER_UNIT
;
1388 if (preferred_stack_boundary
> 1)
1390 /* We don't handle this case yet. To handle it correctly we have
1391 to add the delta, round and subtract the delta.
1392 Currently no machine description requires this support. */
1393 if (stack_pointer_delta
& (preferred_stack_boundary
- 1))
1395 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1398 if (reg_parm_stack_space
> 0)
1401 = size_binop (MAX_EXPR
, args_size
->var
,
1402 ssize_int (reg_parm_stack_space
));
1404 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1405 /* The area corresponding to register parameters is not to count in
1406 the size of the block we need. So make the adjustment. */
1408 = size_binop (MINUS_EXPR
, args_size
->var
,
1409 ssize_int (reg_parm_stack_space
));
1415 preferred_stack_boundary
/= BITS_PER_UNIT
;
1416 if (preferred_stack_boundary
< 1)
1417 preferred_stack_boundary
= 1;
1418 args_size
->constant
= (((args_size
->constant
1419 + stack_pointer_delta
1420 + preferred_stack_boundary
- 1)
1421 / preferred_stack_boundary
1422 * preferred_stack_boundary
)
1423 - stack_pointer_delta
);
1425 args_size
->constant
= MAX (args_size
->constant
,
1426 reg_parm_stack_space
);
1428 #ifdef MAYBE_REG_PARM_STACK_SPACE
1429 if (reg_parm_stack_space
== 0)
1430 args_size
->constant
= 0;
1433 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1434 args_size
->constant
-= reg_parm_stack_space
;
1437 return unadjusted_args_size
;
1440 /* Precompute parameters as needed for a function call.
1442 FLAGS is mask of ECF_* constants.
1444 NUM_ACTUALS is the number of arguments.
1446 ARGS is an array containing information for each argument; this
1447 routine fills in the INITIAL_VALUE and VALUE fields for each
1448 precomputed argument. */
1451 precompute_arguments (flags
, num_actuals
, args
)
1454 struct arg_data
*args
;
1458 /* If this function call is cse'able, precompute all the parameters.
1459 Note that if the parameter is constructed into a temporary, this will
1460 cause an additional copy because the parameter will be constructed
1461 into a temporary location and then copied into the outgoing arguments.
1462 If a parameter contains a call to alloca and this function uses the
1463 stack, precompute the parameter. */
1465 /* If we preallocated the stack space, and some arguments must be passed
1466 on the stack, then we must precompute any parameter which contains a
1467 function call which will store arguments on the stack.
1468 Otherwise, evaluating the parameter may clobber previous parameters
1469 which have already been stored into the stack. (we have code to avoid
1470 such case by saving the outgoing stack arguments, but it results in
1473 for (i
= 0; i
< num_actuals
; i
++)
1474 if ((flags
& (ECF_CONST
| ECF_PURE
))
1475 || calls_function (args
[i
].tree_value
, !ACCUMULATE_OUTGOING_ARGS
))
1477 enum machine_mode mode
;
1479 /* If this is an addressable type, we cannot pre-evaluate it. */
1480 if (TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
)))
1486 = expand_expr (args
[i
].tree_value
, NULL_RTX
, VOIDmode
, 0);
1488 preserve_temp_slots (args
[i
].value
);
1491 /* ANSI doesn't require a sequence point here,
1492 but PCC has one, so this will avoid some problems. */
1495 args
[i
].initial_value
= args
[i
].value
1496 = protect_from_queue (args
[i
].value
, 0);
1498 mode
= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
));
1499 if (mode
!= args
[i
].mode
)
1502 = convert_modes (args
[i
].mode
, mode
,
1503 args
[i
].value
, args
[i
].unsignedp
);
1504 #ifdef PROMOTE_FOR_CALL_ONLY
1505 /* CSE will replace this only if it contains args[i].value
1506 pseudo, so convert it down to the declared mode using
1508 if (GET_CODE (args
[i
].value
) == REG
1509 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
)
1511 args
[i
].initial_value
1512 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1513 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1514 SUBREG_PROMOTED_UNSIGNED_P (args
[i
].initial_value
)
1515 = args
[i
].unsignedp
;
1522 /* Given the current state of MUST_PREALLOCATE and information about
1523 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1524 compute and return the final value for MUST_PREALLOCATE. */
1527 finalize_must_preallocate (must_preallocate
, num_actuals
, args
, args_size
)
1528 int must_preallocate
;
1530 struct arg_data
*args
;
1531 struct args_size
*args_size
;
1533 /* See if we have or want to preallocate stack space.
1535 If we would have to push a partially-in-regs parm
1536 before other stack parms, preallocate stack space instead.
1538 If the size of some parm is not a multiple of the required stack
1539 alignment, we must preallocate.
1541 If the total size of arguments that would otherwise create a copy in
1542 a temporary (such as a CALL) is more than half the total argument list
1543 size, preallocation is faster.
1545 Another reason to preallocate is if we have a machine (like the m88k)
1546 where stack alignment is required to be maintained between every
1547 pair of insns, not just when the call is made. However, we assume here
1548 that such machines either do not have push insns (and hence preallocation
1549 would occur anyway) or the problem is taken care of with
1552 if (! must_preallocate
)
1554 int partial_seen
= 0;
1555 int copy_to_evaluate_size
= 0;
1558 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1560 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1562 else if (partial_seen
&& args
[i
].reg
== 0)
1563 must_preallocate
= 1;
1565 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1566 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1567 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1568 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1569 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1570 copy_to_evaluate_size
1571 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1574 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1575 && args_size
->constant
> 0)
1576 must_preallocate
= 1;
1578 return must_preallocate
;
1581 /* If we preallocated stack space, compute the address of each argument
1582 and store it into the ARGS array.
1584 We need not ensure it is a valid memory address here; it will be
1585 validized when it is used.
1587 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1590 compute_argument_addresses (args
, argblock
, num_actuals
)
1591 struct arg_data
*args
;
1597 rtx arg_reg
= argblock
;
1598 int i
, arg_offset
= 0;
1600 if (GET_CODE (argblock
) == PLUS
)
1601 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1603 for (i
= 0; i
< num_actuals
; i
++)
1605 rtx offset
= ARGS_SIZE_RTX (args
[i
].offset
);
1606 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].slot_offset
);
1609 /* Skip this parm if it will not be passed on the stack. */
1610 if (! args
[i
].pass_on_stack
&& args
[i
].reg
!= 0)
1613 if (GET_CODE (offset
) == CONST_INT
)
1614 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1616 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1618 addr
= plus_constant (addr
, arg_offset
);
1619 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1620 set_mem_attributes (args
[i
].stack
,
1621 TREE_TYPE (args
[i
].tree_value
), 1);
1623 if (GET_CODE (slot_offset
) == CONST_INT
)
1624 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1626 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1628 addr
= plus_constant (addr
, arg_offset
);
1629 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1630 set_mem_attributes (args
[i
].stack_slot
,
1631 TREE_TYPE (args
[i
].tree_value
), 1);
1633 /* Function incoming arguments may overlap with sibling call
1634 outgoing arguments and we cannot allow reordering of reads
1635 from function arguments with stores to outgoing arguments
1636 of sibling calls. */
1637 set_mem_alias_set (args
[i
].stack
, 0);
1638 set_mem_alias_set (args
[i
].stack_slot
, 0);
1643 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1644 in a call instruction.
1646 FNDECL is the tree node for the target function. For an indirect call
1647 FNDECL will be NULL_TREE.
1649 EXP is the CALL_EXPR for this call. */
1652 rtx_for_function_call (fndecl
, exp
)
1658 /* Get the function to call, in the form of RTL. */
1661 /* If this is the first use of the function, see if we need to
1662 make an external definition for it. */
1663 if (! TREE_USED (fndecl
))
1665 assemble_external (fndecl
);
1666 TREE_USED (fndecl
) = 1;
1669 /* Get a SYMBOL_REF rtx for the function address. */
1670 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1673 /* Generate an rtx (probably a pseudo-register) for the address. */
1678 = expand_expr (TREE_OPERAND (exp
, 0), NULL_RTX
, VOIDmode
, 0);
1679 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1685 /* Do the register loads required for any wholly-register parms or any
1686 parms which are passed both on the stack and in a register. Their
1687 expressions were already evaluated.
1689 Mark all register-parms as living through the call, putting these USE
1690 insns in the CALL_INSN_FUNCTION_USAGE field. */
1693 load_register_parameters (args
, num_actuals
, call_fusage
, flags
)
1694 struct arg_data
*args
;
1701 #ifdef LOAD_ARGS_REVERSED
1702 for (i
= num_actuals
- 1; i
>= 0; i
--)
1704 for (i
= 0; i
< num_actuals
; i
++)
1707 rtx reg
= ((flags
& ECF_SIBCALL
)
1708 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1709 int partial
= args
[i
].partial
;
1714 /* Set to non-negative if must move a word at a time, even if just
1715 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1716 we just use a normal move insn. This value can be zero if the
1717 argument is a zero size structure with no fields. */
1718 nregs
= (partial
? partial
1719 : (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1720 ? ((int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
))
1721 + (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
)
1724 /* Handle calls that pass values in multiple non-contiguous
1725 locations. The Irix 6 ABI has examples of this. */
1727 if (GET_CODE (reg
) == PARALLEL
)
1728 emit_group_load (reg
, args
[i
].value
,
1729 int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
)));
1731 /* If simple case, just do move. If normal partial, store_one_arg
1732 has already loaded the register for us. In all other cases,
1733 load the register(s) from memory. */
1735 else if (nregs
== -1)
1736 emit_move_insn (reg
, args
[i
].value
);
1738 /* If we have pre-computed the values to put in the registers in
1739 the case of non-aligned structures, copy them in now. */
1741 else if (args
[i
].n_aligned_regs
!= 0)
1742 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1743 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1744 args
[i
].aligned_regs
[j
]);
1746 else if (partial
== 0 || args
[i
].pass_on_stack
)
1747 move_block_to_reg (REGNO (reg
),
1748 validize_mem (args
[i
].value
), nregs
,
1751 /* Handle calls that pass values in multiple non-contiguous
1752 locations. The Irix 6 ABI has examples of this. */
1753 if (GET_CODE (reg
) == PARALLEL
)
1754 use_group_regs (call_fusage
, reg
);
1755 else if (nregs
== -1)
1756 use_reg (call_fusage
, reg
);
1758 use_regs (call_fusage
, REGNO (reg
), nregs
== 0 ? 1 : nregs
);
1763 /* Try to integrate function. See expand_inline_function for documentation
1764 about the parameters. */
1767 try_to_integrate (fndecl
, actparms
, target
, ignore
, type
, structure_value_addr
)
1773 rtx structure_value_addr
;
1778 rtx old_stack_level
= 0;
1779 int reg_parm_stack_space
= 0;
1781 #ifdef REG_PARM_STACK_SPACE
1782 #ifdef MAYBE_REG_PARM_STACK_SPACE
1783 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
1785 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
1789 before_call
= get_last_insn ();
1791 timevar_push (TV_INTEGRATION
);
1793 temp
= expand_inline_function (fndecl
, actparms
, target
,
1795 structure_value_addr
);
1797 timevar_pop (TV_INTEGRATION
);
1799 /* If inlining succeeded, return. */
1800 if (temp
!= (rtx
) (HOST_WIDE_INT
) - 1)
1802 if (ACCUMULATE_OUTGOING_ARGS
)
1804 /* If the outgoing argument list must be preserved, push
1805 the stack before executing the inlined function if it
1808 for (i
= reg_parm_stack_space
- 1; i
>= 0; i
--)
1809 if (i
< highest_outgoing_arg_in_use
&& stack_usage_map
[i
] != 0)
1812 if (stack_arg_under_construction
|| i
>= 0)
1815 = before_call
? NEXT_INSN (before_call
) : get_insns ();
1816 rtx insn
= NULL_RTX
, seq
;
1818 /* Look for a call in the inline function code.
1819 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1820 nonzero then there is a call and it is not necessary
1821 to scan the insns. */
1823 if (DECL_SAVED_INSNS (fndecl
)->outgoing_args_size
== 0)
1824 for (insn
= first_insn
; insn
; insn
= NEXT_INSN (insn
))
1825 if (GET_CODE (insn
) == CALL_INSN
)
1830 /* Reserve enough stack space so that the largest
1831 argument list of any function call in the inline
1832 function does not overlap the argument list being
1833 evaluated. This is usually an overestimate because
1834 allocate_dynamic_stack_space reserves space for an
1835 outgoing argument list in addition to the requested
1836 space, but there is no way to ask for stack space such
1837 that an argument list of a certain length can be
1840 Add the stack space reserved for register arguments, if
1841 any, in the inline function. What is really needed is the
1842 largest value of reg_parm_stack_space in the inline
1843 function, but that is not available. Using the current
1844 value of reg_parm_stack_space is wrong, but gives
1845 correct results on all supported machines. */
1847 int adjust
= (DECL_SAVED_INSNS (fndecl
)->outgoing_args_size
1848 + reg_parm_stack_space
);
1851 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
1852 allocate_dynamic_stack_space (GEN_INT (adjust
),
1853 NULL_RTX
, BITS_PER_UNIT
);
1856 emit_insns_before (seq
, first_insn
);
1857 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1862 /* If the result is equivalent to TARGET, return TARGET to simplify
1863 checks in store_expr. They can be equivalent but not equal in the
1864 case of a function that returns BLKmode. */
1865 if (temp
!= target
&& rtx_equal_p (temp
, target
))
1870 /* If inlining failed, mark FNDECL as needing to be compiled
1871 separately after all. If function was declared inline,
1873 if (DECL_INLINE (fndecl
) && warn_inline
&& !flag_no_inline
1874 && optimize
> 0 && !TREE_ADDRESSABLE (fndecl
))
1876 warning_with_decl (fndecl
, "inlining failed in call to `%s'");
1877 warning ("called from here");
1879 mark_addressable (fndecl
);
1880 return (rtx
) (HOST_WIDE_INT
) - 1;
1883 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1884 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1885 bytes, then we would need to push some additional bytes to pad the
1886 arguments. So, we compute an adjust to the stack pointer for an
1887 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1888 bytes. Then, when the arguments are pushed the stack will be perfectly
1889 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1890 be popped after the call. Returns the adjustment. */
1893 combine_pending_stack_adjustment_and_call (unadjusted_args_size
,
1895 preferred_unit_stack_boundary
)
1896 int unadjusted_args_size
;
1897 struct args_size
*args_size
;
1898 int preferred_unit_stack_boundary
;
1900 /* The number of bytes to pop so that the stack will be
1901 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1902 HOST_WIDE_INT adjustment
;
1903 /* The alignment of the stack after the arguments are pushed, if we
1904 just pushed the arguments without adjust the stack here. */
1905 HOST_WIDE_INT unadjusted_alignment
;
1907 unadjusted_alignment
1908 = ((stack_pointer_delta
+ unadjusted_args_size
)
1909 % preferred_unit_stack_boundary
);
1911 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1912 as possible -- leaving just enough left to cancel out the
1913 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1914 PENDING_STACK_ADJUST is non-negative, and congruent to
1915 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1917 /* Begin by trying to pop all the bytes. */
1918 unadjusted_alignment
1919 = (unadjusted_alignment
1920 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1921 adjustment
= pending_stack_adjust
;
1922 /* Push enough additional bytes that the stack will be aligned
1923 after the arguments are pushed. */
1924 if (preferred_unit_stack_boundary
> 1)
1926 if (unadjusted_alignment
> 0)
1927 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1929 adjustment
+= unadjusted_alignment
;
1932 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1933 bytes after the call. The right number is the entire
1934 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1935 by the arguments in the first place. */
1937 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1942 /* Scan X expression if it does not dereference any argument slots
1943 we already clobbered by tail call arguments (as noted in stored_args_map
1945 Return non-zero if X expression dereferences such argument slots,
1949 check_sibcall_argument_overlap_1 (x
)
1960 code
= GET_CODE (x
);
1964 if (XEXP (x
, 0) == current_function_internal_arg_pointer
)
1966 else if (GET_CODE (XEXP (x
, 0)) == PLUS
1967 && XEXP (XEXP (x
, 0), 0) ==
1968 current_function_internal_arg_pointer
1969 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
)
1970 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
1974 #ifdef ARGS_GROW_DOWNWARD
1975 i
= -i
- GET_MODE_SIZE (GET_MODE (x
));
1978 for (k
= 0; k
< GET_MODE_SIZE (GET_MODE (x
)); k
++)
1979 if (i
+ k
< stored_args_map
->n_bits
1980 && TEST_BIT (stored_args_map
, i
+ k
))
1986 /* Scan all subexpressions. */
1987 fmt
= GET_RTX_FORMAT (code
);
1988 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
1992 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
1995 else if (*fmt
== 'E')
1997 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
1998 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
2005 /* Scan sequence after INSN if it does not dereference any argument slots
2006 we already clobbered by tail call arguments (as noted in stored_args_map
2007 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2008 Return non-zero if sequence after INSN dereferences such argument slots,
2012 check_sibcall_argument_overlap (insn
, arg
)
2014 struct arg_data
*arg
;
2018 if (insn
== NULL_RTX
)
2019 insn
= get_insns ();
2021 insn
= NEXT_INSN (insn
);
2023 for (; insn
; insn
= NEXT_INSN (insn
))
2025 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
2028 #ifdef ARGS_GROW_DOWNWARD
2029 low
= -arg
->slot_offset
.constant
- arg
->size
.constant
;
2031 low
= arg
->slot_offset
.constant
;
2034 for (high
= low
+ arg
->size
.constant
; low
< high
; low
++)
2035 SET_BIT (stored_args_map
, low
);
2036 return insn
!= NULL_RTX
;
2039 /* Generate all the code for a function call
2040 and return an rtx for its value.
2041 Store the value in TARGET (specified as an rtx) if convenient.
2042 If the value is stored in TARGET then TARGET is returned.
2043 If IGNORE is nonzero, then we ignore the value of the function call. */
2046 expand_call (exp
, target
, ignore
)
2051 /* Nonzero if we are currently expanding a call. */
2052 static int currently_expanding_call
= 0;
2054 /* List of actual parameters. */
2055 tree actparms
= TREE_OPERAND (exp
, 1);
2056 /* RTX for the function to be called. */
2058 /* Sequence of insns to perform a tail recursive "call". */
2059 rtx tail_recursion_insns
= NULL_RTX
;
2060 /* Sequence of insns to perform a normal "call". */
2061 rtx normal_call_insns
= NULL_RTX
;
2062 /* Sequence of insns to perform a tail recursive "call". */
2063 rtx tail_call_insns
= NULL_RTX
;
2064 /* Data type of the function. */
2066 /* Declaration of the function being called,
2067 or 0 if the function is computed (not known by name). */
2070 int try_tail_call
= 1;
2071 int try_tail_recursion
= 1;
2074 /* Register in which non-BLKmode value will be returned,
2075 or 0 if no value or if value is BLKmode. */
2077 /* Address where we should return a BLKmode value;
2078 0 if value not BLKmode. */
2079 rtx structure_value_addr
= 0;
2080 /* Nonzero if that address is being passed by treating it as
2081 an extra, implicit first parameter. Otherwise,
2082 it is passed by being copied directly into struct_value_rtx. */
2083 int structure_value_addr_parm
= 0;
2084 /* Size of aggregate value wanted, or zero if none wanted
2085 or if we are using the non-reentrant PCC calling convention
2086 or expecting the value in registers. */
2087 HOST_WIDE_INT struct_value_size
= 0;
2088 /* Nonzero if called function returns an aggregate in memory PCC style,
2089 by returning the address of where to find it. */
2090 int pcc_struct_value
= 0;
2092 /* Number of actual parameters in this call, including struct value addr. */
2094 /* Number of named args. Args after this are anonymous ones
2095 and they must all go on the stack. */
2098 /* Vector of information about each argument.
2099 Arguments are numbered in the order they will be pushed,
2100 not the order they are written. */
2101 struct arg_data
*args
;
2103 /* Total size in bytes of all the stack-parms scanned so far. */
2104 struct args_size args_size
;
2105 struct args_size adjusted_args_size
;
2106 /* Size of arguments before any adjustments (such as rounding). */
2107 int unadjusted_args_size
;
2108 /* Data on reg parms scanned so far. */
2109 CUMULATIVE_ARGS args_so_far
;
2110 /* Nonzero if a reg parm has been scanned. */
2112 /* Nonzero if this is an indirect function call. */
2114 /* Nonzero if we must avoid push-insns in the args for this call.
2115 If stack space is allocated for register parameters, but not by the
2116 caller, then it is preallocated in the fixed part of the stack frame.
2117 So the entire argument block must then be preallocated (i.e., we
2118 ignore PUSH_ROUNDING in that case). */
2120 int must_preallocate
= !PUSH_ARGS
;
2122 /* Size of the stack reserved for parameter registers. */
2123 int reg_parm_stack_space
= 0;
2125 /* Address of space preallocated for stack parms
2126 (on machines that lack push insns), or 0 if space not preallocated. */
2129 /* Mask of ECF_ flags. */
2131 /* Nonzero if this is a call to an inline function. */
2132 int is_integrable
= 0;
2133 #ifdef REG_PARM_STACK_SPACE
2134 /* Define the boundary of the register parm stack space that needs to be
2136 int low_to_save
= -1, high_to_save
;
2137 rtx save_area
= 0; /* Place that it is saved */
2140 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
2141 char *initial_stack_usage_map
= stack_usage_map
;
2142 int old_stack_arg_under_construction
= 0;
2144 rtx old_stack_level
= 0;
2145 int old_pending_adj
= 0;
2146 int old_inhibit_defer_pop
= inhibit_defer_pop
;
2147 int old_stack_allocated
;
2149 tree p
= TREE_OPERAND (exp
, 0);
2151 /* The alignment of the stack, in bits. */
2152 HOST_WIDE_INT preferred_stack_boundary
;
2153 /* The alignment of the stack, in bytes. */
2154 HOST_WIDE_INT preferred_unit_stack_boundary
;
2156 /* See if this is "nothrow" function call. */
2157 if (TREE_NOTHROW (exp
))
2158 flags
|= ECF_NOTHROW
;
2160 /* See if we can find a DECL-node for the actual function.
2161 As a result, decide whether this is a call to an integrable function. */
2163 fndecl
= get_callee_fndecl (exp
);
2167 && fndecl
!= current_function_decl
2168 && DECL_INLINE (fndecl
)
2169 && DECL_SAVED_INSNS (fndecl
)
2170 && DECL_SAVED_INSNS (fndecl
)->inlinable
)
2172 else if (! TREE_ADDRESSABLE (fndecl
))
2174 /* In case this function later becomes inlinable,
2175 record that there was already a non-inline call to it.
2177 Use abstraction instead of setting TREE_ADDRESSABLE
2179 if (DECL_INLINE (fndecl
) && warn_inline
&& !flag_no_inline
2182 warning_with_decl (fndecl
, "can't inline call to `%s'");
2183 warning ("called from here");
2185 mark_addressable (fndecl
);
2188 flags
|= flags_from_decl_or_type (fndecl
);
2191 /* If we don't have specific function to call, see if we have a
2192 attributes set in the type. */
2194 flags
|= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p
)));
2196 /* Mark if the function returns with the stack pointer depressed. */
2197 if (TREE_CODE (TREE_TYPE (TREE_TYPE (p
))) == FUNCTION_TYPE
2198 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (TREE_TYPE (p
))))
2200 flags
|= ECF_SP_DEPRESSED
;
2201 flags
&= ~(ECF_PURE
| ECF_CONST
);
2204 #ifdef REG_PARM_STACK_SPACE
2205 #ifdef MAYBE_REG_PARM_STACK_SPACE
2206 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
2208 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
2212 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2213 if (reg_parm_stack_space
> 0 && PUSH_ARGS
)
2214 must_preallocate
= 1;
2217 /* Warn if this value is an aggregate type,
2218 regardless of which calling convention we are using for it. */
2219 if (warn_aggregate_return
&& AGGREGATE_TYPE_P (TREE_TYPE (exp
)))
2220 warning ("function call has aggregate value");
2222 /* Set up a place to return a structure. */
2224 /* Cater to broken compilers. */
2225 if (aggregate_value_p (exp
))
2227 /* This call returns a big structure. */
2228 flags
&= ~(ECF_CONST
| ECF_PURE
);
2230 #ifdef PCC_STATIC_STRUCT_RETURN
2232 pcc_struct_value
= 1;
2233 /* Easier than making that case work right. */
2236 /* In case this is a static function, note that it has been
2238 if (! TREE_ADDRESSABLE (fndecl
))
2239 mark_addressable (fndecl
);
2243 #else /* not PCC_STATIC_STRUCT_RETURN */
2245 struct_value_size
= int_size_in_bytes (TREE_TYPE (exp
));
2247 if (target
&& GET_CODE (target
) == MEM
)
2248 structure_value_addr
= XEXP (target
, 0);
2251 /* For variable-sized objects, we must be called with a target
2252 specified. If we were to allocate space on the stack here,
2253 we would have no way of knowing when to free it. */
2254 rtx d
= assign_temp (TREE_TYPE (exp
), 1, 1, 1);
2256 mark_temp_addr_taken (d
);
2257 structure_value_addr
= XEXP (d
, 0);
2261 #endif /* not PCC_STATIC_STRUCT_RETURN */
2264 /* If called function is inline, try to integrate it. */
2268 rtx temp
= try_to_integrate (fndecl
, actparms
, target
,
2269 ignore
, TREE_TYPE (exp
),
2270 structure_value_addr
);
2271 if (temp
!= (rtx
) (HOST_WIDE_INT
) - 1)
2275 /* Figure out the amount to which the stack should be aligned. */
2276 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2278 /* Operand 0 is a pointer-to-function; get the type of the function. */
2279 funtype
= TREE_TYPE (TREE_OPERAND (exp
, 0));
2280 if (! POINTER_TYPE_P (funtype
))
2282 funtype
= TREE_TYPE (funtype
);
2284 /* See if this is a call to a function that can return more than once
2285 or a call to longjmp or malloc. */
2286 flags
|= special_function_p (fndecl
, flags
);
2288 if (flags
& ECF_MAY_BE_ALLOCA
)
2289 current_function_calls_alloca
= 1;
2291 /* If struct_value_rtx is 0, it means pass the address
2292 as if it were an extra parameter. */
2293 if (structure_value_addr
&& struct_value_rtx
== 0)
2295 /* If structure_value_addr is a REG other than
2296 virtual_outgoing_args_rtx, we can use always use it. If it
2297 is not a REG, we must always copy it into a register.
2298 If it is virtual_outgoing_args_rtx, we must copy it to another
2299 register in some cases. */
2300 rtx temp
= (GET_CODE (structure_value_addr
) != REG
2301 || (ACCUMULATE_OUTGOING_ARGS
2302 && stack_arg_under_construction
2303 && structure_value_addr
== virtual_outgoing_args_rtx
)
2304 ? copy_addr_to_reg (structure_value_addr
)
2305 : structure_value_addr
);
2308 = tree_cons (error_mark_node
,
2309 make_tree (build_pointer_type (TREE_TYPE (funtype
)),
2312 structure_value_addr_parm
= 1;
2315 /* Count the arguments and set NUM_ACTUALS. */
2316 for (p
= actparms
, num_actuals
= 0; p
; p
= TREE_CHAIN (p
))
2319 /* Compute number of named args.
2320 Normally, don't include the last named arg if anonymous args follow.
2321 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2322 (If no anonymous args follow, the result of list_length is actually
2323 one too large. This is harmless.)
2325 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2326 zero, this machine will be able to place unnamed args that were
2327 passed in registers into the stack. So treat all args as named.
2328 This allows the insns emitting for a specific argument list to be
2329 independent of the function declaration.
2331 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2332 reliable way to pass unnamed args in registers, so we must force
2333 them into memory. */
2335 if ((STRICT_ARGUMENT_NAMING
2336 || ! PRETEND_OUTGOING_VARARGS_NAMED
)
2337 && TYPE_ARG_TYPES (funtype
) != 0)
2339 = (list_length (TYPE_ARG_TYPES (funtype
))
2340 /* Don't include the last named arg. */
2341 - (STRICT_ARGUMENT_NAMING
? 0 : 1)
2342 /* Count the struct value address, if it is passed as a parm. */
2343 + structure_value_addr_parm
);
2345 /* If we know nothing, treat all args as named. */
2346 n_named_args
= num_actuals
;
2348 /* Start updating where the next arg would go.
2350 On some machines (such as the PA) indirect calls have a different
2351 calling convention than normal calls. The last argument in
2352 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2354 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, (fndecl
== 0));
2356 /* Make a vector to hold all the information about each arg. */
2357 args
= (struct arg_data
*) alloca (num_actuals
* sizeof (struct arg_data
));
2358 memset ((char *) args
, 0, num_actuals
* sizeof (struct arg_data
));
2360 /* Build up entries in the ARGS array, compute the size of the
2361 arguments into ARGS_SIZE, etc. */
2362 initialize_argument_information (num_actuals
, args
, &args_size
,
2363 n_named_args
, actparms
, fndecl
,
2364 &args_so_far
, reg_parm_stack_space
,
2365 &old_stack_level
, &old_pending_adj
,
2366 &must_preallocate
, &flags
);
2370 /* If this function requires a variable-sized argument list, don't
2371 try to make a cse'able block for this call. We may be able to
2372 do this eventually, but it is too complicated to keep track of
2373 what insns go in the cse'able block and which don't. */
2375 flags
&= ~(ECF_CONST
| ECF_PURE
);
2376 must_preallocate
= 1;
2379 /* Now make final decision about preallocating stack space. */
2380 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2384 /* If the structure value address will reference the stack pointer, we
2385 must stabilize it. We don't need to do this if we know that we are
2386 not going to adjust the stack pointer in processing this call. */
2388 if (structure_value_addr
2389 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2390 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2391 structure_value_addr
))
2393 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2394 structure_value_addr
= copy_to_reg (structure_value_addr
);
2396 /* Tail calls can make things harder to debug, and we're traditionally
2397 pushed these optimizations into -O2. Don't try if we're already
2398 expanding a call, as that means we're an argument. Don't try if
2399 there's cleanups, as we know there's code to follow the call.
2401 If rtx_equal_function_value_matters is false, that means we've
2402 finished with regular parsing. Which means that some of the
2403 machinery we use to generate tail-calls is no longer in place.
2404 This is most often true of sjlj-exceptions, which we couldn't
2405 tail-call to anyway. */
2407 if (currently_expanding_call
++ != 0
2408 || !flag_optimize_sibling_calls
2409 || !rtx_equal_function_value_matters
2410 || any_pending_cleanups (1)
2412 try_tail_call
= try_tail_recursion
= 0;
2414 /* Tail recursion fails, when we are not dealing with recursive calls. */
2415 if (!try_tail_recursion
2416 || TREE_CODE (TREE_OPERAND (exp
, 0)) != ADDR_EXPR
2417 || TREE_OPERAND (TREE_OPERAND (exp
, 0), 0) != current_function_decl
)
2418 try_tail_recursion
= 0;
2420 /* Rest of purposes for tail call optimizations to fail. */
2422 #ifdef HAVE_sibcall_epilogue
2423 !HAVE_sibcall_epilogue
2428 /* Doing sibling call optimization needs some work, since
2429 structure_value_addr can be allocated on the stack.
2430 It does not seem worth the effort since few optimizable
2431 sibling calls will return a structure. */
2432 || structure_value_addr
!= NULL_RTX
2433 /* If the register holding the address is a callee saved
2434 register, then we lose. We have no way to prevent that,
2435 so we only allow calls to named functions. */
2436 /* ??? This could be done by having the insn constraints
2437 use a register class that is all call-clobbered. Any
2438 reload insns generated to fix things up would appear
2439 before the sibcall_epilogue. */
2440 || fndecl
== NULL_TREE
2441 || (flags
& (ECF_RETURNS_TWICE
| ECF_LONGJMP
))
2442 || TREE_THIS_VOLATILE (fndecl
)
2443 || !FUNCTION_OK_FOR_SIBCALL (fndecl
)
2444 /* If this function requires more stack slots than the current
2445 function, we cannot change it into a sibling call. */
2446 || args_size
.constant
> current_function_args_size
2447 /* If the callee pops its own arguments, then it must pop exactly
2448 the same number of arguments as the current function. */
2449 || RETURN_POPS_ARGS (fndecl
, funtype
, args_size
.constant
)
2450 != RETURN_POPS_ARGS (current_function_decl
,
2451 TREE_TYPE (current_function_decl
),
2452 current_function_args_size
))
2455 if (try_tail_call
|| try_tail_recursion
)
2458 actparms
= NULL_TREE
;
2459 /* Ok, we're going to give the tail call the old college try.
2460 This means we're going to evaluate the function arguments
2461 up to three times. There are two degrees of badness we can
2462 encounter, those that can be unsaved and those that can't.
2463 (See unsafe_for_reeval commentary for details.)
2465 Generate a new argument list. Pass safe arguments through
2466 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2467 For hard badness, evaluate them now and put their resulting
2468 rtx in a temporary VAR_DECL.
2470 initialize_argument_information has ordered the array for the
2471 order to be pushed, and we must remember this when reconstructing
2472 the original argument order. */
2474 if (PUSH_ARGS_REVERSED
)
2483 i
= num_actuals
- 1;
2487 for (; i
!= end
; i
+= inc
)
2489 switch (unsafe_for_reeval (args
[i
].tree_value
))
2494 case 1: /* Mildly unsafe. */
2495 args
[i
].tree_value
= unsave_expr (args
[i
].tree_value
);
2498 case 2: /* Wildly unsafe. */
2500 tree var
= build_decl (VAR_DECL
, NULL_TREE
,
2501 TREE_TYPE (args
[i
].tree_value
));
2503 expand_expr (args
[i
].tree_value
, NULL_RTX
,
2504 VOIDmode
, EXPAND_NORMAL
));
2505 args
[i
].tree_value
= var
;
2512 /* We need to build actparms for optimize_tail_recursion. We can
2513 safely trash away TREE_PURPOSE, since it is unused by this
2515 if (try_tail_recursion
)
2516 actparms
= tree_cons (NULL_TREE
, args
[i
].tree_value
, actparms
);
2518 /* Expanding one of those dangerous arguments could have added
2519 cleanups, but otherwise give it a whirl. */
2520 if (any_pending_cleanups (1))
2521 try_tail_call
= try_tail_recursion
= 0;
2524 /* Generate a tail recursion sequence when calling ourselves. */
2526 if (try_tail_recursion
)
2528 /* We want to emit any pending stack adjustments before the tail
2529 recursion "call". That way we know any adjustment after the tail
2530 recursion call can be ignored if we indeed use the tail recursion
2532 int save_pending_stack_adjust
= pending_stack_adjust
;
2533 int save_stack_pointer_delta
= stack_pointer_delta
;
2535 /* Emit any queued insns now; otherwise they would end up in
2536 only one of the alternates. */
2539 /* Use a new sequence to hold any RTL we generate. We do not even
2540 know if we will use this RTL yet. The final decision can not be
2541 made until after RTL generation for the entire function is
2544 /* If expanding any of the arguments creates cleanups, we can't
2545 do a tailcall. So, we'll need to pop the pending cleanups
2546 list. If, however, all goes well, and there are no cleanups
2547 then the call to expand_start_target_temps will have no
2549 expand_start_target_temps ();
2550 if (optimize_tail_recursion (actparms
, get_last_insn ()))
2552 if (any_pending_cleanups (1))
2553 try_tail_call
= try_tail_recursion
= 0;
2555 tail_recursion_insns
= get_insns ();
2557 expand_end_target_temps ();
2560 /* Restore the original pending stack adjustment for the sibling and
2561 normal call cases below. */
2562 pending_stack_adjust
= save_pending_stack_adjust
;
2563 stack_pointer_delta
= save_stack_pointer_delta
;
2566 if (profile_arc_flag
&& (flags
& ECF_FORK_OR_EXEC
))
2568 /* A fork duplicates the profile information, and an exec discards
2569 it. We can't rely on fork/exec to be paired. So write out the
2570 profile information we have gathered so far, and clear it. */
2571 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2572 is subject to race conditions, just as with multithreaded
2575 emit_library_call (gen_rtx_SYMBOL_REF (Pmode
, "__bb_fork_func"),
2580 /* Ensure current function's preferred stack boundary is at least
2581 what we need. We don't have to increase alignment for recursive
2583 if (cfun
->preferred_stack_boundary
< preferred_stack_boundary
2584 && fndecl
!= current_function_decl
)
2585 cfun
->preferred_stack_boundary
= preferred_stack_boundary
;
2587 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2589 function_call_count
++;
2591 /* We want to make two insn chains; one for a sibling call, the other
2592 for a normal call. We will select one of the two chains after
2593 initial RTL generation is complete. */
2594 for (pass
= 0; pass
< 2; pass
++)
2596 int sibcall_failure
= 0;
2597 /* We want to emit any pending stack adjustments before the tail
2598 recursion "call". That way we know any adjustment after the tail
2599 recursion call can be ignored if we indeed use the tail recursion
2601 int save_pending_stack_adjust
= 0;
2602 int save_stack_pointer_delta
= 0;
2604 rtx before_call
, next_arg_reg
;
2608 if (! try_tail_call
)
2611 /* Emit any queued insns now; otherwise they would end up in
2612 only one of the alternates. */
2615 /* State variables we need to save and restore between
2617 save_pending_stack_adjust
= pending_stack_adjust
;
2618 save_stack_pointer_delta
= stack_pointer_delta
;
2621 flags
&= ~ECF_SIBCALL
;
2623 flags
|= ECF_SIBCALL
;
2625 /* Other state variables that we must reinitialize each time
2626 through the loop (that are not initialized by the loop itself). */
2630 /* Start a new sequence for the normal call case.
2632 From this point on, if the sibling call fails, we want to set
2633 sibcall_failure instead of continuing the loop. */
2638 /* We know at this point that there are not currently any
2639 pending cleanups. If, however, in the process of evaluating
2640 the arguments we were to create some, we'll need to be
2641 able to get rid of them. */
2642 expand_start_target_temps ();
2645 /* Don't let pending stack adjusts add up to too much.
2646 Also, do all pending adjustments now if there is any chance
2647 this might be a call to alloca or if we are expanding a sibling
2649 if (pending_stack_adjust
>= 32
2650 || (pending_stack_adjust
> 0 && (flags
& ECF_MAY_BE_ALLOCA
))
2652 do_pending_stack_adjust ();
2654 /* When calling a const function, we must pop the stack args right away,
2655 so that the pop is deleted or moved with the call. */
2656 if (flags
& (ECF_CONST
| ECF_PURE
))
2659 /* Push the temporary stack slot level so that we can free any
2660 temporaries we make. */
2663 #ifdef FINAL_REG_PARM_STACK_SPACE
2664 reg_parm_stack_space
= FINAL_REG_PARM_STACK_SPACE (args_size
.constant
,
2667 /* Precompute any arguments as needed. */
2669 precompute_arguments (flags
, num_actuals
, args
);
2671 /* Now we are about to start emitting insns that can be deleted
2672 if a libcall is deleted. */
2673 if (flags
& (ECF_CONST
| ECF_PURE
| ECF_MALLOC
))
2676 adjusted_args_size
= args_size
;
2677 /* Compute the actual size of the argument block required. The variable
2678 and constant sizes must be combined, the size may have to be rounded,
2679 and there may be a minimum required size. When generating a sibcall
2680 pattern, do not round up, since we'll be re-using whatever space our
2682 unadjusted_args_size
2683 = compute_argument_block_size (reg_parm_stack_space
,
2684 &adjusted_args_size
,
2686 : preferred_stack_boundary
));
2688 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2690 /* The argument block when performing a sibling call is the
2691 incoming argument block. */
2694 argblock
= virtual_incoming_args_rtx
;
2695 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2696 sbitmap_zero (stored_args_map
);
2699 /* If we have no actual push instructions, or shouldn't use them,
2700 make space for all args right now. */
2701 else if (adjusted_args_size
.var
!= 0)
2703 if (old_stack_level
== 0)
2705 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
2706 old_pending_adj
= pending_stack_adjust
;
2707 pending_stack_adjust
= 0;
2708 /* stack_arg_under_construction says whether a stack arg is
2709 being constructed at the old stack level. Pushing the stack
2710 gets a clean outgoing argument block. */
2711 old_stack_arg_under_construction
= stack_arg_under_construction
;
2712 stack_arg_under_construction
= 0;
2714 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2718 /* Note that we must go through the motions of allocating an argument
2719 block even if the size is zero because we may be storing args
2720 in the area reserved for register arguments, which may be part of
2723 int needed
= adjusted_args_size
.constant
;
2725 /* Store the maximum argument space used. It will be pushed by
2726 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2729 if (needed
> current_function_outgoing_args_size
)
2730 current_function_outgoing_args_size
= needed
;
2732 if (must_preallocate
)
2734 if (ACCUMULATE_OUTGOING_ARGS
)
2736 /* Since the stack pointer will never be pushed, it is
2737 possible for the evaluation of a parm to clobber
2738 something we have already written to the stack.
2739 Since most function calls on RISC machines do not use
2740 the stack, this is uncommon, but must work correctly.
2742 Therefore, we save any area of the stack that was already
2743 written and that we are using. Here we set up to do this
2744 by making a new stack usage map from the old one. The
2745 actual save will be done by store_one_arg.
2747 Another approach might be to try to reorder the argument
2748 evaluations to avoid this conflicting stack usage. */
2750 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2751 /* Since we will be writing into the entire argument area,
2752 the map must be allocated for its entire size, not just
2753 the part that is the responsibility of the caller. */
2754 needed
+= reg_parm_stack_space
;
2757 #ifdef ARGS_GROW_DOWNWARD
2758 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2761 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2765 = (char *) alloca (highest_outgoing_arg_in_use
);
2767 if (initial_highest_arg_in_use
)
2768 memcpy (stack_usage_map
, initial_stack_usage_map
,
2769 initial_highest_arg_in_use
);
2771 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2772 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2773 (highest_outgoing_arg_in_use
2774 - initial_highest_arg_in_use
));
2777 /* The address of the outgoing argument list must not be
2778 copied to a register here, because argblock would be left
2779 pointing to the wrong place after the call to
2780 allocate_dynamic_stack_space below. */
2782 argblock
= virtual_outgoing_args_rtx
;
2786 if (inhibit_defer_pop
== 0)
2788 /* Try to reuse some or all of the pending_stack_adjust
2789 to get this space. */
2791 = (combine_pending_stack_adjustment_and_call
2792 (unadjusted_args_size
,
2793 &adjusted_args_size
,
2794 preferred_unit_stack_boundary
));
2796 /* combine_pending_stack_adjustment_and_call computes
2797 an adjustment before the arguments are allocated.
2798 Account for them and see whether or not the stack
2799 needs to go up or down. */
2800 needed
= unadjusted_args_size
- needed
;
2804 /* We're releasing stack space. */
2805 /* ??? We can avoid any adjustment at all if we're
2806 already aligned. FIXME. */
2807 pending_stack_adjust
= -needed
;
2808 do_pending_stack_adjust ();
2812 /* We need to allocate space. We'll do that in
2813 push_block below. */
2814 pending_stack_adjust
= 0;
2817 /* Special case this because overhead of `push_block' in
2818 this case is non-trivial. */
2820 argblock
= virtual_outgoing_args_rtx
;
2822 argblock
= push_block (GEN_INT (needed
), 0, 0);
2824 /* We only really need to call `copy_to_reg' in the case
2825 where push insns are going to be used to pass ARGBLOCK
2826 to a function call in ARGS. In that case, the stack
2827 pointer changes value from the allocation point to the
2828 call point, and hence the value of
2829 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2830 as well always do it. */
2831 argblock
= copy_to_reg (argblock
);
2833 /* The save/restore code in store_one_arg handles all
2834 cases except one: a constructor call (including a C
2835 function returning a BLKmode struct) to initialize
2837 if (stack_arg_under_construction
)
2839 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2840 rtx push_size
= GEN_INT (reg_parm_stack_space
2841 + adjusted_args_size
.constant
);
2843 rtx push_size
= GEN_INT (adjusted_args_size
.constant
);
2845 if (old_stack_level
== 0)
2847 emit_stack_save (SAVE_BLOCK
, &old_stack_level
,
2849 old_pending_adj
= pending_stack_adjust
;
2850 pending_stack_adjust
= 0;
2851 /* stack_arg_under_construction says whether a stack
2852 arg is being constructed at the old stack level.
2853 Pushing the stack gets a clean outgoing argument
2855 old_stack_arg_under_construction
2856 = stack_arg_under_construction
;
2857 stack_arg_under_construction
= 0;
2858 /* Make a new map for the new argument list. */
2859 stack_usage_map
= (char *)
2860 alloca (highest_outgoing_arg_in_use
);
2861 memset (stack_usage_map
, 0, highest_outgoing_arg_in_use
);
2862 highest_outgoing_arg_in_use
= 0;
2864 allocate_dynamic_stack_space (push_size
, NULL_RTX
,
2867 /* If argument evaluation might modify the stack pointer,
2868 copy the address of the argument list to a register. */
2869 for (i
= 0; i
< num_actuals
; i
++)
2870 if (args
[i
].pass_on_stack
)
2872 argblock
= copy_addr_to_reg (argblock
);
2879 compute_argument_addresses (args
, argblock
, num_actuals
);
2881 /* If we push args individually in reverse order, perform stack alignment
2882 before the first push (the last arg). */
2883 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2884 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2886 /* When the stack adjustment is pending, we get better code
2887 by combining the adjustments. */
2888 if (pending_stack_adjust
2889 && ! (flags
& (ECF_CONST
| ECF_PURE
))
2890 && ! inhibit_defer_pop
)
2892 pending_stack_adjust
2893 = (combine_pending_stack_adjustment_and_call
2894 (unadjusted_args_size
,
2895 &adjusted_args_size
,
2896 preferred_unit_stack_boundary
));
2897 do_pending_stack_adjust ();
2899 else if (argblock
== 0)
2900 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2901 - unadjusted_args_size
));
2903 /* Now that the stack is properly aligned, pops can't safely
2904 be deferred during the evaluation of the arguments. */
2907 funexp
= rtx_for_function_call (fndecl
, exp
);
2909 /* Figure out the register where the value, if any, will come back. */
2911 if (TYPE_MODE (TREE_TYPE (exp
)) != VOIDmode
2912 && ! structure_value_addr
)
2914 if (pcc_struct_value
)
2915 valreg
= hard_function_value (build_pointer_type (TREE_TYPE (exp
)),
2916 fndecl
, (pass
== 0));
2918 valreg
= hard_function_value (TREE_TYPE (exp
), fndecl
, (pass
== 0));
2921 /* Precompute all register parameters. It isn't safe to compute anything
2922 once we have started filling any specific hard regs. */
2923 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2925 #ifdef REG_PARM_STACK_SPACE
2926 /* Save the fixed argument area if it's part of the caller's frame and
2927 is clobbered by argument setup for this call. */
2928 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2929 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2930 &low_to_save
, &high_to_save
);
2933 /* Now store (and compute if necessary) all non-register parms.
2934 These come before register parms, since they can require block-moves,
2935 which could clobber the registers used for register parms.
2936 Parms which have partial registers are not stored here,
2937 but we do preallocate space here if they want that. */
2939 for (i
= 0; i
< num_actuals
; i
++)
2940 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2942 rtx before_arg
= get_last_insn ();
2944 if (store_one_arg (&args
[i
], argblock
, flags
,
2945 adjusted_args_size
.var
!= 0,
2946 reg_parm_stack_space
)
2948 && check_sibcall_argument_overlap (before_arg
,
2950 sibcall_failure
= 1;
2953 /* If we have a parm that is passed in registers but not in memory
2954 and whose alignment does not permit a direct copy into registers,
2955 make a group of pseudos that correspond to each register that we
2957 if (STRICT_ALIGNMENT
)
2958 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2960 /* Now store any partially-in-registers parm.
2961 This is the last place a block-move can happen. */
2963 for (i
= 0; i
< num_actuals
; i
++)
2964 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2966 rtx before_arg
= get_last_insn ();
2968 if (store_one_arg (&args
[i
], argblock
, flags
,
2969 adjusted_args_size
.var
!= 0,
2970 reg_parm_stack_space
)
2972 && check_sibcall_argument_overlap (before_arg
,
2974 sibcall_failure
= 1;
2977 /* If we pushed args in forward order, perform stack alignment
2978 after pushing the last arg. */
2979 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
2980 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2981 - unadjusted_args_size
));
2983 /* If register arguments require space on the stack and stack space
2984 was not preallocated, allocate stack space here for arguments
2985 passed in registers. */
2986 #ifdef OUTGOING_REG_PARM_STACK_SPACE
2987 if (!ACCUMULATE_OUTGOING_ARGS
2988 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
2989 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
2992 /* Pass the function the address in which to return a
2994 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
2996 emit_move_insn (struct_value_rtx
,
2998 force_operand (structure_value_addr
,
3001 if (GET_CODE (struct_value_rtx
) == REG
)
3002 use_reg (&call_fusage
, struct_value_rtx
);
3005 funexp
= prepare_call_address (funexp
, fndecl
, &call_fusage
,
3006 reg_parm_seen
, pass
== 0);
3008 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
);
3010 /* Perform postincrements before actually calling the function. */
3013 /* Save a pointer to the last insn before the call, so that we can
3014 later safely search backwards to find the CALL_INSN. */
3015 before_call
= get_last_insn ();
3017 /* Set up next argument register. For sibling calls on machines
3018 with register windows this should be the incoming register. */
3019 #ifdef FUNCTION_INCOMING_ARG
3021 next_arg_reg
= FUNCTION_INCOMING_ARG (args_so_far
, VOIDmode
,
3025 next_arg_reg
= FUNCTION_ARG (args_so_far
, VOIDmode
,
3028 /* All arguments and registers used for the call must be set up by
3031 /* Stack must be properly aligned now. */
3032 if (pass
&& stack_pointer_delta
% preferred_unit_stack_boundary
)
3035 /* Generate the actual call instruction. */
3036 emit_call_1 (funexp
, fndecl
, funtype
, unadjusted_args_size
,
3037 adjusted_args_size
.constant
, struct_value_size
,
3038 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
3041 /* Verify that we've deallocated all the stack we used. */
3043 && old_stack_allocated
!= stack_pointer_delta
- pending_stack_adjust
)
3046 /* If call is cse'able, make appropriate pair of reg-notes around it.
3047 Test valreg so we don't crash; may safely ignore `const'
3048 if return type is void. Disable for PARALLEL return values, because
3049 we have no way to move such values into a pseudo register. */
3051 && (flags
& (ECF_CONST
| ECF_PURE
))
3052 && valreg
!= 0 && GET_CODE (valreg
) != PARALLEL
)
3055 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
3058 /* Mark the return value as a pointer if needed. */
3059 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
3060 mark_reg_pointer (temp
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp
))));
3062 /* Construct an "equal form" for the value which mentions all the
3063 arguments in order as well as the function name. */
3064 for (i
= 0; i
< num_actuals
; i
++)
3065 note
= gen_rtx_EXPR_LIST (VOIDmode
, args
[i
].initial_value
, note
);
3066 note
= gen_rtx_EXPR_LIST (VOIDmode
, funexp
, note
);
3068 insns
= get_insns ();
3071 if (flags
& ECF_PURE
)
3072 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3073 gen_rtx_USE (VOIDmode
,
3074 gen_rtx_MEM (BLKmode
,
3075 gen_rtx_SCRATCH (VOIDmode
))), note
);
3077 emit_libcall_block (insns
, temp
, valreg
, note
);
3081 else if (flags
& (ECF_CONST
| ECF_PURE
))
3083 /* Otherwise, just write out the sequence without a note. */
3084 rtx insns
= get_insns ();
3089 else if (flags
& ECF_MALLOC
)
3091 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
3094 /* The return value from a malloc-like function is a pointer. */
3095 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
3096 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
3098 emit_move_insn (temp
, valreg
);
3100 /* The return value from a malloc-like function can not alias
3102 last
= get_last_insn ();
3104 gen_rtx_EXPR_LIST (REG_NOALIAS
, temp
, REG_NOTES (last
));
3106 /* Write out the sequence. */
3107 insns
= get_insns ();
3113 /* For calls to `setjmp', etc., inform flow.c it should complain
3114 if nonvolatile values are live. For functions that cannot return,
3115 inform flow that control does not fall through. */
3117 if ((flags
& (ECF_NORETURN
| ECF_LONGJMP
)) || pass
== 0)
3119 /* The barrier must be emitted
3120 immediately after the CALL_INSN. Some ports emit more
3121 than just a CALL_INSN above, so we must search for it here. */
3123 rtx last
= get_last_insn ();
3124 while (GET_CODE (last
) != CALL_INSN
)
3126 last
= PREV_INSN (last
);
3127 /* There was no CALL_INSN? */
3128 if (last
== before_call
)
3132 emit_barrier_after (last
);
3135 if (flags
& ECF_LONGJMP
)
3136 current_function_calls_longjmp
= 1;
3138 /* If this function is returning into a memory location marked as
3139 readonly, it means it is initializing that location. But we normally
3140 treat functions as not clobbering such locations, so we need to
3141 specify that this one does. */
3142 if (target
!= 0 && GET_CODE (target
) == MEM
3143 && structure_value_addr
!= 0 && RTX_UNCHANGING_P (target
))
3144 emit_insn (gen_rtx_CLOBBER (VOIDmode
, target
));
3146 /* If value type not void, return an rtx for the value. */
3148 /* If there are cleanups to be called, don't use a hard reg as target.
3149 We need to double check this and see if it matters anymore. */
3150 if (any_pending_cleanups (1))
3152 if (target
&& REG_P (target
)
3153 && REGNO (target
) < FIRST_PSEUDO_REGISTER
)
3155 sibcall_failure
= 1;
3158 if (TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
3161 target
= const0_rtx
;
3163 else if (structure_value_addr
)
3165 if (target
== 0 || GET_CODE (target
) != MEM
)
3168 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
3169 memory_address (TYPE_MODE (TREE_TYPE (exp
)),
3170 structure_value_addr
));
3171 set_mem_attributes (target
, exp
, 1);
3174 else if (pcc_struct_value
)
3176 /* This is the special C++ case where we need to
3177 know what the true target was. We take care to
3178 never use this value more than once in one expression. */
3179 target
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
3180 copy_to_reg (valreg
));
3181 set_mem_attributes (target
, exp
, 1);
3183 /* Handle calls that return values in multiple non-contiguous locations.
3184 The Irix 6 ABI has examples of this. */
3185 else if (GET_CODE (valreg
) == PARALLEL
)
3189 /* This will only be assigned once, so it can be readonly. */
3190 tree nt
= build_qualified_type (TREE_TYPE (exp
),
3191 (TYPE_QUALS (TREE_TYPE (exp
))
3192 | TYPE_QUAL_CONST
));
3194 target
= assign_temp (nt
, 0, 1, 1);
3195 preserve_temp_slots (target
);
3198 if (! rtx_equal_p (target
, valreg
))
3199 emit_group_store (target
, valreg
,
3200 int_size_in_bytes (TREE_TYPE (exp
)));
3202 /* We can not support sibling calls for this case. */
3203 sibcall_failure
= 1;
3206 && GET_MODE (target
) == TYPE_MODE (TREE_TYPE (exp
))
3207 && GET_MODE (target
) == GET_MODE (valreg
))
3209 /* TARGET and VALREG cannot be equal at this point because the
3210 latter would not have REG_FUNCTION_VALUE_P true, while the
3211 former would if it were referring to the same register.
3213 If they refer to the same register, this move will be a no-op,
3214 except when function inlining is being done. */
3215 emit_move_insn (target
, valreg
);
3217 else if (TYPE_MODE (TREE_TYPE (exp
)) == BLKmode
)
3219 target
= copy_blkmode_from_reg (target
, valreg
, TREE_TYPE (exp
));
3221 /* We can not support sibling calls for this case. */
3222 sibcall_failure
= 1;
3225 target
= copy_to_reg (valreg
);
3227 #ifdef PROMOTE_FUNCTION_RETURN
3228 /* If we promoted this return value, make the proper SUBREG. TARGET
3229 might be const0_rtx here, so be careful. */
3230 if (GET_CODE (target
) == REG
3231 && TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
3232 && GET_MODE (target
) != TYPE_MODE (TREE_TYPE (exp
)))
3234 tree type
= TREE_TYPE (exp
);
3235 int unsignedp
= TREE_UNSIGNED (type
);
3238 /* If we don't promote as expected, something is wrong. */
3239 if (GET_MODE (target
)
3240 != promote_mode (type
, TYPE_MODE (type
), &unsignedp
, 1))
3243 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
3244 && GET_MODE_SIZE (GET_MODE (target
))
3245 > GET_MODE_SIZE (TYPE_MODE (type
)))
3247 offset
= GET_MODE_SIZE (GET_MODE (target
))
3248 - GET_MODE_SIZE (TYPE_MODE (type
));
3249 if (! BYTES_BIG_ENDIAN
)
3250 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
3251 else if (! WORDS_BIG_ENDIAN
)
3252 offset
%= UNITS_PER_WORD
;
3254 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
3255 SUBREG_PROMOTED_VAR_P (target
) = 1;
3256 SUBREG_PROMOTED_UNSIGNED_P (target
) = unsignedp
;
3260 /* If size of args is variable or this was a constructor call for a stack
3261 argument, restore saved stack-pointer value. */
3263 if (old_stack_level
&& ! (flags
& ECF_SP_DEPRESSED
))
3265 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
3266 pending_stack_adjust
= old_pending_adj
;
3267 stack_arg_under_construction
= old_stack_arg_under_construction
;
3268 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3269 stack_usage_map
= initial_stack_usage_map
;
3270 sibcall_failure
= 1;
3272 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
3274 #ifdef REG_PARM_STACK_SPACE
3277 restore_fixed_argument_area (save_area
, argblock
,
3278 high_to_save
, low_to_save
);
3282 /* If we saved any argument areas, restore them. */
3283 for (i
= 0; i
< num_actuals
; i
++)
3284 if (args
[i
].save_area
)
3286 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
3288 = gen_rtx_MEM (save_mode
,
3289 memory_address (save_mode
,
3290 XEXP (args
[i
].stack_slot
, 0)));
3292 if (save_mode
!= BLKmode
)
3293 emit_move_insn (stack_area
, args
[i
].save_area
);
3295 emit_block_move (stack_area
,
3296 validize_mem (args
[i
].save_area
),
3297 GEN_INT (args
[i
].size
.constant
));
3300 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3301 stack_usage_map
= initial_stack_usage_map
;
3304 /* If this was alloca, record the new stack level for nonlocal gotos.
3305 Check for the handler slots since we might not have a save area
3306 for non-local gotos. */
3308 if ((flags
& ECF_MAY_BE_ALLOCA
) && nonlocal_goto_handler_slots
!= 0)
3309 emit_stack_save (SAVE_NONLOCAL
, &nonlocal_goto_stack_level
, NULL_RTX
);
3313 /* Free up storage we no longer need. */
3314 for (i
= 0; i
< num_actuals
; ++i
)
3315 if (args
[i
].aligned_regs
)
3316 free (args
[i
].aligned_regs
);
3320 /* Undo the fake expand_start_target_temps we did earlier. If
3321 there had been any cleanups created, we've already set
3323 expand_end_target_temps ();
3326 insns
= get_insns ();
3331 tail_call_insns
= insns
;
3333 /* Restore the pending stack adjustment now that we have
3334 finished generating the sibling call sequence. */
3336 pending_stack_adjust
= save_pending_stack_adjust
;
3337 stack_pointer_delta
= save_stack_pointer_delta
;
3339 /* Prepare arg structure for next iteration. */
3340 for (i
= 0; i
< num_actuals
; i
++)
3343 args
[i
].aligned_regs
= 0;
3347 sbitmap_free (stored_args_map
);
3350 normal_call_insns
= insns
;
3352 /* If something prevents making this a sibling call,
3353 zero out the sequence. */
3354 if (sibcall_failure
)
3355 tail_call_insns
= NULL_RTX
;
3358 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3359 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3360 can happen if the arguments to this function call an inline
3361 function who's expansion contains another CALL_PLACEHOLDER.
3363 If there are any C_Ps in any of these sequences, replace them
3364 with their normal call. */
3366 for (insn
= normal_call_insns
; insn
; insn
= NEXT_INSN (insn
))
3367 if (GET_CODE (insn
) == CALL_INSN
3368 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3369 replace_call_placeholder (insn
, sibcall_use_normal
);
3371 for (insn
= tail_call_insns
; insn
; insn
= NEXT_INSN (insn
))
3372 if (GET_CODE (insn
) == CALL_INSN
3373 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3374 replace_call_placeholder (insn
, sibcall_use_normal
);
3376 for (insn
= tail_recursion_insns
; insn
; insn
= NEXT_INSN (insn
))
3377 if (GET_CODE (insn
) == CALL_INSN
3378 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3379 replace_call_placeholder (insn
, sibcall_use_normal
);
3381 /* If this was a potential tail recursion site, then emit a
3382 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3383 One of them will be selected later. */
3384 if (tail_recursion_insns
|| tail_call_insns
)
3386 /* The tail recursion label must be kept around. We could expose
3387 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3388 and makes determining true tail recursion sites difficult.
3390 So we set LABEL_PRESERVE_P here, then clear it when we select
3391 one of the call sequences after rtl generation is complete. */
3392 if (tail_recursion_insns
)
3393 LABEL_PRESERVE_P (tail_recursion_label
) = 1;
3394 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode
, normal_call_insns
,
3396 tail_recursion_insns
,
3397 tail_recursion_label
));
3400 emit_insns (normal_call_insns
);
3402 currently_expanding_call
--;
3404 /* If this function returns with the stack pointer depressed, ensure
3405 this block saves and restores the stack pointer, show it was
3406 changed, and adjust for any outgoing arg space. */
3407 if (flags
& ECF_SP_DEPRESSED
)
3409 clear_pending_stack_adjust ();
3410 emit_insn (gen_rtx (CLOBBER
, VOIDmode
, stack_pointer_rtx
));
3411 emit_move_insn (virtual_stack_dynamic_rtx
, stack_pointer_rtx
);
3412 save_stack_pointer ();
3418 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3419 The RETVAL parameter specifies whether return value needs to be saved, other
3420 parameters are documented in the emit_library_call function below. */
3423 emit_library_call_value_1 (retval
, orgfun
, value
, fn_type
, outmode
, nargs
, p
)
3427 enum libcall_type fn_type
;
3428 enum machine_mode outmode
;
3432 /* Total size in bytes of all the stack-parms scanned so far. */
3433 struct args_size args_size
;
3434 /* Size of arguments before any adjustments (such as rounding). */
3435 struct args_size original_args_size
;
3440 struct args_size alignment_pad
;
3442 CUMULATIVE_ARGS args_so_far
;
3446 enum machine_mode mode
;
3449 struct args_size offset
;
3450 struct args_size size
;
3454 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3455 rtx call_fusage
= 0;
3458 int pcc_struct_value
= 0;
3459 int struct_value_size
= 0;
3461 int reg_parm_stack_space
= 0;
3465 #ifdef REG_PARM_STACK_SPACE
3466 /* Define the boundary of the register parm stack space that needs to be
3468 int low_to_save
= -1, high_to_save
= 0;
3469 rtx save_area
= 0; /* Place that it is saved. */
3472 /* Size of the stack reserved for parameter registers. */
3473 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3474 char *initial_stack_usage_map
= stack_usage_map
;
3476 #ifdef REG_PARM_STACK_SPACE
3477 #ifdef MAYBE_REG_PARM_STACK_SPACE
3478 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
3480 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3484 /* By default, library functions can not throw. */
3485 flags
= ECF_NOTHROW
;
3492 /* Nothing to do here. */
3494 case LCT_CONST_MAKE_BLOCK
:
3497 case LCT_PURE_MAKE_BLOCK
:
3501 flags
|= ECF_NORETURN
;
3504 flags
= ECF_NORETURN
;
3506 case LCT_ALWAYS_RETURN
:
3507 flags
= ECF_ALWAYS_RETURN
;
3509 case LCT_RETURNS_TWICE
:
3510 flags
= ECF_RETURNS_TWICE
;
3515 /* Ensure current function's preferred stack boundary is at least
3517 if (cfun
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3518 cfun
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3520 /* If this kind of value comes back in memory,
3521 decide where in memory it should come back. */
3522 if (outmode
!= VOIDmode
&& aggregate_value_p (type_for_mode (outmode
, 0)))
3524 #ifdef PCC_STATIC_STRUCT_RETURN
3526 = hard_function_value (build_pointer_type (type_for_mode (outmode
, 0)),
3528 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3529 pcc_struct_value
= 1;
3531 value
= gen_reg_rtx (outmode
);
3532 #else /* not PCC_STATIC_STRUCT_RETURN */
3533 struct_value_size
= GET_MODE_SIZE (outmode
);
3534 if (value
!= 0 && GET_CODE (value
) == MEM
)
3537 mem_value
= assign_temp (type_for_mode (outmode
, 0), 0, 1, 1);
3540 /* This call returns a big structure. */
3541 flags
&= ~(ECF_CONST
| ECF_PURE
);
3544 /* ??? Unfinished: must pass the memory address as an argument. */
3546 /* Copy all the libcall-arguments out of the varargs data
3547 and into a vector ARGVEC.
3549 Compute how to pass each argument. We only support a very small subset
3550 of the full argument passing conventions to limit complexity here since
3551 library functions shouldn't have many args. */
3553 argvec
= (struct arg
*) alloca ((nargs
+ 1) * sizeof (struct arg
));
3554 memset ((char *) argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3556 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3557 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3559 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0);
3562 args_size
.constant
= 0;
3567 /* Now we are about to start emitting insns that can be deleted
3568 if a libcall is deleted. */
3569 if (flags
& (ECF_CONST
| ECF_PURE
))
3574 /* If there's a structure value address to be passed,
3575 either pass it in the special place, or pass it as an extra argument. */
3576 if (mem_value
&& struct_value_rtx
== 0 && ! pcc_struct_value
)
3578 rtx addr
= XEXP (mem_value
, 0);
3581 /* Make sure it is a reasonable operand for a move or push insn. */
3582 if (GET_CODE (addr
) != REG
&& GET_CODE (addr
) != MEM
3583 && ! (CONSTANT_P (addr
) && LEGITIMATE_CONSTANT_P (addr
)))
3584 addr
= force_operand (addr
, NULL_RTX
);
3586 argvec
[count
].value
= addr
;
3587 argvec
[count
].mode
= Pmode
;
3588 argvec
[count
].partial
= 0;
3590 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, Pmode
, NULL_TREE
, 1);
3591 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3592 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, Pmode
, NULL_TREE
, 1))
3596 locate_and_pad_parm (Pmode
, NULL_TREE
,
3597 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3600 argvec
[count
].reg
!= 0,
3602 NULL_TREE
, &args_size
, &argvec
[count
].offset
,
3603 &argvec
[count
].size
, &alignment_pad
);
3605 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3606 || reg_parm_stack_space
> 0)
3607 args_size
.constant
+= argvec
[count
].size
.constant
;
3609 FUNCTION_ARG_ADVANCE (args_so_far
, Pmode
, (tree
) 0, 1);
3614 for (; count
< nargs
; count
++)
3616 rtx val
= va_arg (p
, rtx
);
3617 enum machine_mode mode
= va_arg (p
, enum machine_mode
);
3619 /* We cannot convert the arg value to the mode the library wants here;
3620 must do it earlier where we know the signedness of the arg. */
3622 || (GET_MODE (val
) != mode
&& GET_MODE (val
) != VOIDmode
))
3625 /* On some machines, there's no way to pass a float to a library fcn.
3626 Pass it as a double instead. */
3627 #ifdef LIBGCC_NEEDS_DOUBLE
3628 if (LIBGCC_NEEDS_DOUBLE
&& mode
== SFmode
)
3629 val
= convert_modes (DFmode
, SFmode
, val
, 0), mode
= DFmode
;
3632 /* There's no need to call protect_from_queue, because
3633 either emit_move_insn or emit_push_insn will do that. */
3635 /* Make sure it is a reasonable operand for a move or push insn. */
3636 if (GET_CODE (val
) != REG
&& GET_CODE (val
) != MEM
3637 && ! (CONSTANT_P (val
) && LEGITIMATE_CONSTANT_P (val
)))
3638 val
= force_operand (val
, NULL_RTX
);
3640 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3641 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far
, mode
, NULL_TREE
, 1))
3645 #ifdef FUNCTION_ARG_CALLEE_COPIES
3646 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far
, mode
,
3651 if (GET_MODE (val
) == MEM
&& ! must_copy
)
3655 slot
= assign_temp (type_for_mode (mode
, 0), 0, 1, 1);
3656 emit_move_insn (slot
, val
);
3660 tree type
= type_for_mode (mode
, 0);
3662 slot
= gen_rtx_MEM (mode
,
3663 expand_expr (build1 (ADDR_EXPR
,
3666 make_tree (type
, val
)),
3667 NULL_RTX
, VOIDmode
, 0));
3670 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3671 gen_rtx_USE (VOIDmode
, slot
),
3674 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3675 gen_rtx_CLOBBER (VOIDmode
,
3680 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3684 argvec
[count
].value
= val
;
3685 argvec
[count
].mode
= mode
;
3687 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, mode
, NULL_TREE
, 1);
3689 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3690 argvec
[count
].partial
3691 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, mode
, NULL_TREE
, 1);
3693 argvec
[count
].partial
= 0;
3696 locate_and_pad_parm (mode
, NULL_TREE
,
3697 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3700 argvec
[count
].reg
!= 0,
3702 NULL_TREE
, &args_size
, &argvec
[count
].offset
,
3703 &argvec
[count
].size
, &alignment_pad
);
3705 if (argvec
[count
].size
.var
)
3708 if (reg_parm_stack_space
== 0 && argvec
[count
].partial
)
3709 argvec
[count
].size
.constant
-= argvec
[count
].partial
* UNITS_PER_WORD
;
3711 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3712 || reg_parm_stack_space
> 0)
3713 args_size
.constant
+= argvec
[count
].size
.constant
;
3715 FUNCTION_ARG_ADVANCE (args_so_far
, mode
, (tree
) 0, 1);
3718 #ifdef FINAL_REG_PARM_STACK_SPACE
3719 reg_parm_stack_space
= FINAL_REG_PARM_STACK_SPACE (args_size
.constant
,
3722 /* If this machine requires an external definition for library
3723 functions, write one out. */
3724 assemble_external_libcall (fun
);
3726 original_args_size
= args_size
;
3727 args_size
.constant
= (((args_size
.constant
3728 + stack_pointer_delta
3732 - stack_pointer_delta
);
3734 args_size
.constant
= MAX (args_size
.constant
,
3735 reg_parm_stack_space
);
3737 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3738 args_size
.constant
-= reg_parm_stack_space
;
3741 if (args_size
.constant
> current_function_outgoing_args_size
)
3742 current_function_outgoing_args_size
= args_size
.constant
;
3744 if (ACCUMULATE_OUTGOING_ARGS
)
3746 /* Since the stack pointer will never be pushed, it is possible for
3747 the evaluation of a parm to clobber something we have already
3748 written to the stack. Since most function calls on RISC machines
3749 do not use the stack, this is uncommon, but must work correctly.
3751 Therefore, we save any area of the stack that was already written
3752 and that we are using. Here we set up to do this by making a new
3753 stack usage map from the old one.
3755 Another approach might be to try to reorder the argument
3756 evaluations to avoid this conflicting stack usage. */
3758 needed
= args_size
.constant
;
3760 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3761 /* Since we will be writing into the entire argument area, the
3762 map must be allocated for its entire size, not just the part that
3763 is the responsibility of the caller. */
3764 needed
+= reg_parm_stack_space
;
3767 #ifdef ARGS_GROW_DOWNWARD
3768 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3771 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3774 stack_usage_map
= (char *) alloca (highest_outgoing_arg_in_use
);
3776 if (initial_highest_arg_in_use
)
3777 memcpy (stack_usage_map
, initial_stack_usage_map
,
3778 initial_highest_arg_in_use
);
3780 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3781 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3782 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3785 /* We must be careful to use virtual regs before they're instantiated,
3786 and real regs afterwards. Loop optimization, for example, can create
3787 new libcalls after we've instantiated the virtual regs, and if we
3788 use virtuals anyway, they won't match the rtl patterns. */
3790 if (virtuals_instantiated
)
3791 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3793 argblock
= virtual_outgoing_args_rtx
;
3798 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3801 /* If we push args individually in reverse order, perform stack alignment
3802 before the first push (the last arg). */
3803 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3804 anti_adjust_stack (GEN_INT (args_size
.constant
3805 - original_args_size
.constant
));
3807 if (PUSH_ARGS_REVERSED
)
3818 #ifdef REG_PARM_STACK_SPACE
3819 if (ACCUMULATE_OUTGOING_ARGS
)
3821 /* The argument list is the property of the called routine and it
3822 may clobber it. If the fixed area has been used for previous
3823 parameters, we must save and restore it.
3825 Here we compute the boundary of the that needs to be saved, if any. */
3827 #ifdef ARGS_GROW_DOWNWARD
3828 for (count
= 0; count
< reg_parm_stack_space
+ 1; count
++)
3830 for (count
= 0; count
< reg_parm_stack_space
; count
++)
3833 if (count
>= highest_outgoing_arg_in_use
3834 || stack_usage_map
[count
] == 0)
3837 if (low_to_save
== -1)
3838 low_to_save
= count
;
3840 high_to_save
= count
;
3843 if (low_to_save
>= 0)
3845 int num_to_save
= high_to_save
- low_to_save
+ 1;
3846 enum machine_mode save_mode
3847 = mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
3850 /* If we don't have the required alignment, must do this in BLKmode. */
3851 if ((low_to_save
& (MIN (GET_MODE_SIZE (save_mode
),
3852 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
3853 save_mode
= BLKmode
;
3855 #ifdef ARGS_GROW_DOWNWARD
3856 stack_area
= gen_rtx_MEM (save_mode
,
3857 memory_address (save_mode
,
3858 plus_constant (argblock
,
3861 stack_area
= gen_rtx_MEM (save_mode
,
3862 memory_address (save_mode
,
3863 plus_constant (argblock
,
3866 if (save_mode
== BLKmode
)
3868 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
3869 set_mem_align (save_area
, PARM_BOUNDARY
);
3870 emit_block_move (validize_mem (save_area
), stack_area
,
3871 GEN_INT (num_to_save
));
3875 save_area
= gen_reg_rtx (save_mode
);
3876 emit_move_insn (save_area
, stack_area
);
3882 /* Push the args that need to be pushed. */
3884 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3885 are to be pushed. */
3886 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3888 enum machine_mode mode
= argvec
[argnum
].mode
;
3889 rtx val
= argvec
[argnum
].value
;
3890 rtx reg
= argvec
[argnum
].reg
;
3891 int partial
= argvec
[argnum
].partial
;
3892 int lower_bound
= 0, upper_bound
= 0, i
;
3894 if (! (reg
!= 0 && partial
== 0))
3896 if (ACCUMULATE_OUTGOING_ARGS
)
3898 /* If this is being stored into a pre-allocated, fixed-size,
3899 stack area, save any previous data at that location. */
3901 #ifdef ARGS_GROW_DOWNWARD
3902 /* stack_slot is negative, but we want to index stack_usage_map
3903 with positive values. */
3904 upper_bound
= -argvec
[argnum
].offset
.constant
+ 1;
3905 lower_bound
= upper_bound
- argvec
[argnum
].size
.constant
;
3907 lower_bound
= argvec
[argnum
].offset
.constant
;
3908 upper_bound
= lower_bound
+ argvec
[argnum
].size
.constant
;
3911 for (i
= lower_bound
; i
< upper_bound
; i
++)
3912 if (stack_usage_map
[i
]
3913 /* Don't store things in the fixed argument area at this
3914 point; it has already been saved. */
3915 && i
> reg_parm_stack_space
)
3918 if (i
!= upper_bound
)
3920 /* We need to make a save area. See what mode we can make
3922 enum machine_mode save_mode
3923 = mode_for_size (argvec
[argnum
].size
.constant
3931 plus_constant (argblock
,
3932 argvec
[argnum
].offset
.constant
)));
3933 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3935 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3939 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, 0, partial
, reg
, 0,
3940 argblock
, GEN_INT (argvec
[argnum
].offset
.constant
),
3941 reg_parm_stack_space
, ARGS_SIZE_RTX (alignment_pad
));
3943 /* Now mark the segment we just used. */
3944 if (ACCUMULATE_OUTGOING_ARGS
)
3945 for (i
= lower_bound
; i
< upper_bound
; i
++)
3946 stack_usage_map
[i
] = 1;
3952 /* If we pushed args in forward order, perform stack alignment
3953 after pushing the last arg. */
3954 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3955 anti_adjust_stack (GEN_INT (args_size
.constant
3956 - original_args_size
.constant
));
3958 if (PUSH_ARGS_REVERSED
)
3963 fun
= prepare_call_address (fun
, NULL_TREE
, &call_fusage
, 0, 0);
3965 /* Now load any reg parms into their regs. */
3967 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3968 are to be pushed. */
3969 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3971 rtx val
= argvec
[argnum
].value
;
3972 rtx reg
= argvec
[argnum
].reg
;
3973 int partial
= argvec
[argnum
].partial
;
3975 /* Handle calls that pass values in multiple non-contiguous
3976 locations. The PA64 has examples of this for library calls. */
3977 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3978 emit_group_load (reg
, val
, GET_MODE_SIZE (GET_MODE (val
)));
3979 else if (reg
!= 0 && partial
== 0)
3980 emit_move_insn (reg
, val
);
3985 /* Any regs containing parms remain in use through the call. */
3986 for (count
= 0; count
< nargs
; count
++)
3988 rtx reg
= argvec
[count
].reg
;
3989 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3990 use_group_regs (&call_fusage
, reg
);
3992 use_reg (&call_fusage
, reg
);
3995 /* Pass the function the address in which to return a structure value. */
3996 if (mem_value
!= 0 && struct_value_rtx
!= 0 && ! pcc_struct_value
)
3998 emit_move_insn (struct_value_rtx
,
4000 force_operand (XEXP (mem_value
, 0),
4002 if (GET_CODE (struct_value_rtx
) == REG
)
4003 use_reg (&call_fusage
, struct_value_rtx
);
4006 /* Don't allow popping to be deferred, since then
4007 cse'ing of library calls could delete a call and leave the pop. */
4009 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
4010 ? hard_libcall_value (outmode
) : NULL_RTX
);
4012 /* Stack must be properly aligned now. */
4013 if (stack_pointer_delta
& (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1))
4016 before_call
= get_last_insn ();
4018 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4019 will set inhibit_defer_pop to that value. */
4020 /* The return type is needed to decide how many bytes the function pops.
4021 Signedness plays no role in that, so for simplicity, we pretend it's
4022 always signed. We also assume that the list of arguments passed has
4023 no impact, so we pretend it is unknown. */
4026 get_identifier (XSTR (orgfun
, 0)),
4027 build_function_type (outmode
== VOIDmode
? void_type_node
4028 : type_for_mode (outmode
, 0), NULL_TREE
),
4029 original_args_size
.constant
, args_size
.constant
,
4031 FUNCTION_ARG (args_so_far
, VOIDmode
, void_type_node
, 1),
4033 old_inhibit_defer_pop
+ 1, call_fusage
, flags
);
4035 /* For calls to `setjmp', etc., inform flow.c it should complain
4036 if nonvolatile values are live. For functions that cannot return,
4037 inform flow that control does not fall through. */
4039 if (flags
& (ECF_NORETURN
| ECF_LONGJMP
))
4041 /* The barrier note must be emitted
4042 immediately after the CALL_INSN. Some ports emit more than
4043 just a CALL_INSN above, so we must search for it here. */
4045 rtx last
= get_last_insn ();
4046 while (GET_CODE (last
) != CALL_INSN
)
4048 last
= PREV_INSN (last
);
4049 /* There was no CALL_INSN? */
4050 if (last
== before_call
)
4054 emit_barrier_after (last
);
4057 /* Now restore inhibit_defer_pop to its actual original value. */
4060 /* If call is cse'able, make appropriate pair of reg-notes around it.
4061 Test valreg so we don't crash; may safely ignore `const'
4062 if return type is void. Disable for PARALLEL return values, because
4063 we have no way to move such values into a pseudo register. */
4064 if ((flags
& (ECF_CONST
| ECF_PURE
))
4065 && valreg
!= 0 && GET_CODE (valreg
) != PARALLEL
)
4068 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
4072 /* Construct an "equal form" for the value which mentions all the
4073 arguments in order as well as the function name. */
4074 for (i
= 0; i
< nargs
; i
++)
4075 note
= gen_rtx_EXPR_LIST (VOIDmode
, argvec
[i
].value
, note
);
4076 note
= gen_rtx_EXPR_LIST (VOIDmode
, fun
, note
);
4078 insns
= get_insns ();
4081 if (flags
& ECF_PURE
)
4082 note
= gen_rtx_EXPR_LIST (VOIDmode
,
4083 gen_rtx_USE (VOIDmode
,
4084 gen_rtx_MEM (BLKmode
,
4085 gen_rtx_SCRATCH (VOIDmode
))), note
);
4087 emit_libcall_block (insns
, temp
, valreg
, note
);
4091 else if (flags
& (ECF_CONST
| ECF_PURE
))
4093 /* Otherwise, just write out the sequence without a note. */
4094 rtx insns
= get_insns ();
4101 /* Copy the value to the right place. */
4102 if (outmode
!= VOIDmode
&& retval
)
4108 if (value
!= mem_value
)
4109 emit_move_insn (value
, mem_value
);
4111 else if (value
!= 0)
4112 emit_move_insn (value
, hard_libcall_value (outmode
));
4114 value
= hard_libcall_value (outmode
);
4117 if (ACCUMULATE_OUTGOING_ARGS
)
4119 #ifdef REG_PARM_STACK_SPACE
4122 enum machine_mode save_mode
= GET_MODE (save_area
);
4123 #ifdef ARGS_GROW_DOWNWARD
4125 = gen_rtx_MEM (save_mode
,
4126 memory_address (save_mode
,
4127 plus_constant (argblock
,
4131 = gen_rtx_MEM (save_mode
,
4132 memory_address (save_mode
,
4133 plus_constant (argblock
, low_to_save
)));
4136 set_mem_align (stack_area
, PARM_BOUNDARY
);
4137 if (save_mode
!= BLKmode
)
4138 emit_move_insn (stack_area
, save_area
);
4140 emit_block_move (stack_area
, validize_mem (save_area
),
4141 GEN_INT (high_to_save
- low_to_save
+ 1));
4145 /* If we saved any argument areas, restore them. */
4146 for (count
= 0; count
< nargs
; count
++)
4147 if (argvec
[count
].save_area
)
4149 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
4151 = gen_rtx_MEM (save_mode
,
4154 plus_constant (argblock
,
4155 argvec
[count
].offset
.constant
)));
4157 emit_move_insn (stack_area
, argvec
[count
].save_area
);
4160 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4161 stack_usage_map
= initial_stack_usage_map
;
4168 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4169 (emitting the queue unless NO_QUEUE is nonzero),
4170 for a value of mode OUTMODE,
4171 with NARGS different arguments, passed as alternating rtx values
4172 and machine_modes to convert them to.
4173 The rtx values should have been passed through protect_from_queue already.
4175 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4176 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4177 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4178 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4179 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4180 or other LCT_ value for other types of library calls. */
4183 emit_library_call
VPARAMS((rtx orgfun
, enum libcall_type fn_type
,
4184 enum machine_mode outmode
, int nargs
, ...))
4187 VA_FIXEDARG (p
, rtx
, orgfun
);
4188 VA_FIXEDARG (p
, int, fn_type
);
4189 VA_FIXEDARG (p
, enum machine_mode
, outmode
);
4190 VA_FIXEDARG (p
, int, nargs
);
4192 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
4197 /* Like emit_library_call except that an extra argument, VALUE,
4198 comes second and says where to store the result.
4199 (If VALUE is zero, this function chooses a convenient way
4200 to return the value.
4202 This function returns an rtx for where the value is to be found.
4203 If VALUE is nonzero, VALUE is returned. */
4206 emit_library_call_value
VPARAMS((rtx orgfun
, rtx value
,
4207 enum libcall_type fn_type
,
4208 enum machine_mode outmode
, int nargs
, ...))
4213 VA_FIXEDARG (p
, rtx
, orgfun
);
4214 VA_FIXEDARG (p
, rtx
, value
);
4215 VA_FIXEDARG (p
, int, fn_type
);
4216 VA_FIXEDARG (p
, enum machine_mode
, outmode
);
4217 VA_FIXEDARG (p
, int, nargs
);
4219 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
4227 /* Store a single argument for a function call
4228 into the register or memory area where it must be passed.
4229 *ARG describes the argument value and where to pass it.
4231 ARGBLOCK is the address of the stack-block for all the arguments,
4232 or 0 on a machine where arguments are pushed individually.
4234 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4235 so must be careful about how the stack is used.
4237 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4238 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4239 that we need not worry about saving and restoring the stack.
4241 FNDECL is the declaration of the function we are calling.
4243 Return non-zero if this arg should cause sibcall failure,
4247 store_one_arg (arg
, argblock
, flags
, variable_size
, reg_parm_stack_space
)
4248 struct arg_data
*arg
;
4251 int variable_size ATTRIBUTE_UNUSED
;
4252 int reg_parm_stack_space
;
4254 tree pval
= arg
->tree_value
;
4258 int i
, lower_bound
= 0, upper_bound
= 0;
4259 int sibcall_failure
= 0;
4261 if (TREE_CODE (pval
) == ERROR_MARK
)
4264 /* Push a new temporary level for any temporaries we make for
4268 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4270 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4271 save any previous data at that location. */
4272 if (argblock
&& ! variable_size
&& arg
->stack
)
4274 #ifdef ARGS_GROW_DOWNWARD
4275 /* stack_slot is negative, but we want to index stack_usage_map
4276 with positive values. */
4277 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4278 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4282 lower_bound
= upper_bound
- arg
->size
.constant
;
4284 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4285 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4289 upper_bound
= lower_bound
+ arg
->size
.constant
;
4292 for (i
= lower_bound
; i
< upper_bound
; i
++)
4293 if (stack_usage_map
[i
]
4294 /* Don't store things in the fixed argument area at this point;
4295 it has already been saved. */
4296 && i
> reg_parm_stack_space
)
4299 if (i
!= upper_bound
)
4301 /* We need to make a save area. See what mode we can make it. */
4302 enum machine_mode save_mode
4303 = mode_for_size (arg
->size
.constant
* BITS_PER_UNIT
, MODE_INT
, 1);
4305 = gen_rtx_MEM (save_mode
,
4306 memory_address (save_mode
,
4307 XEXP (arg
->stack_slot
, 0)));
4309 if (save_mode
== BLKmode
)
4311 tree ot
= TREE_TYPE (arg
->tree_value
);
4312 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4313 | TYPE_QUAL_CONST
));
4315 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4316 preserve_temp_slots (arg
->save_area
);
4317 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4318 expr_size (arg
->tree_value
));
4322 arg
->save_area
= gen_reg_rtx (save_mode
);
4323 emit_move_insn (arg
->save_area
, stack_area
);
4327 /* Now that we have saved any slots that will be overwritten by this
4328 store, mark all slots this store will use. We must do this before
4329 we actually expand the argument since the expansion itself may
4330 trigger library calls which might need to use the same stack slot. */
4331 if (argblock
&& ! variable_size
&& arg
->stack
)
4332 for (i
= lower_bound
; i
< upper_bound
; i
++)
4333 stack_usage_map
[i
] = 1;
4336 /* If this isn't going to be placed on both the stack and in registers,
4337 set up the register and number of words. */
4338 if (! arg
->pass_on_stack
)
4339 reg
= arg
->reg
, partial
= arg
->partial
;
4341 if (reg
!= 0 && partial
== 0)
4342 /* Being passed entirely in a register. We shouldn't be called in
4346 /* If this arg needs special alignment, don't load the registers
4348 if (arg
->n_aligned_regs
!= 0)
4351 /* If this is being passed partially in a register, we can't evaluate
4352 it directly into its stack slot. Otherwise, we can. */
4353 if (arg
->value
== 0)
4355 /* stack_arg_under_construction is nonzero if a function argument is
4356 being evaluated directly into the outgoing argument list and
4357 expand_call must take special action to preserve the argument list
4358 if it is called recursively.
4360 For scalar function arguments stack_usage_map is sufficient to
4361 determine which stack slots must be saved and restored. Scalar
4362 arguments in general have pass_on_stack == 0.
4364 If this argument is initialized by a function which takes the
4365 address of the argument (a C++ constructor or a C function
4366 returning a BLKmode structure), then stack_usage_map is
4367 insufficient and expand_call must push the stack around the
4368 function call. Such arguments have pass_on_stack == 1.
4370 Note that it is always safe to set stack_arg_under_construction,
4371 but this generates suboptimal code if set when not needed. */
4373 if (arg
->pass_on_stack
)
4374 stack_arg_under_construction
++;
4376 arg
->value
= expand_expr (pval
,
4378 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4379 ? NULL_RTX
: arg
->stack
,
4382 /* If we are promoting object (or for any other reason) the mode
4383 doesn't agree, convert the mode. */
4385 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4386 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4387 arg
->value
, arg
->unsignedp
);
4389 if (arg
->pass_on_stack
)
4390 stack_arg_under_construction
--;
4393 /* Don't allow anything left on stack from computation
4394 of argument to alloca. */
4395 if (flags
& ECF_MAY_BE_ALLOCA
)
4396 do_pending_stack_adjust ();
4398 if (arg
->value
== arg
->stack
)
4399 /* If the value is already in the stack slot, we are done. */
4401 else if (arg
->mode
!= BLKmode
)
4405 /* Argument is a scalar, not entirely passed in registers.
4406 (If part is passed in registers, arg->partial says how much
4407 and emit_push_insn will take care of putting it there.)
4409 Push it, and if its size is less than the
4410 amount of space allocated to it,
4411 also bump stack pointer by the additional space.
4412 Note that in C the default argument promotions
4413 will prevent such mismatches. */
4415 size
= GET_MODE_SIZE (arg
->mode
);
4416 /* Compute how much space the push instruction will push.
4417 On many machines, pushing a byte will advance the stack
4418 pointer by a halfword. */
4419 #ifdef PUSH_ROUNDING
4420 size
= PUSH_ROUNDING (size
);
4424 /* Compute how much space the argument should get:
4425 round up to a multiple of the alignment for arguments. */
4426 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4427 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4428 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4429 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4431 /* This isn't already where we want it on the stack, so put it there.
4432 This can either be done with push or copy insns. */
4433 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
, 0,
4434 partial
, reg
, used
- size
, argblock
,
4435 ARGS_SIZE_RTX (arg
->offset
), reg_parm_stack_space
,
4436 ARGS_SIZE_RTX (arg
->alignment_pad
));
4440 /* BLKmode, at least partly to be pushed. */
4445 /* Pushing a nonscalar.
4446 If part is passed in registers, PARTIAL says how much
4447 and emit_push_insn will take care of putting it there. */
4449 /* Round its size up to a multiple
4450 of the allocation unit for arguments. */
4452 if (arg
->size
.var
!= 0)
4455 size_rtx
= ARGS_SIZE_RTX (arg
->size
);
4459 /* PUSH_ROUNDING has no effect on us, because
4460 emit_push_insn for BLKmode is careful to avoid it. */
4461 excess
= (arg
->size
.constant
- int_size_in_bytes (TREE_TYPE (pval
))
4462 + partial
* UNITS_PER_WORD
);
4463 size_rtx
= expr_size (pval
);
4466 if ((flags
& ECF_SIBCALL
) && GET_CODE (arg
->value
) == MEM
)
4468 /* emit_push_insn might not work properly if arg->value and
4469 argblock + arg->offset areas overlap. */
4473 if (XEXP (x
, 0) == current_function_internal_arg_pointer
4474 || (GET_CODE (XEXP (x
, 0)) == PLUS
4475 && XEXP (XEXP (x
, 0), 0) ==
4476 current_function_internal_arg_pointer
4477 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
))
4479 if (XEXP (x
, 0) != current_function_internal_arg_pointer
)
4480 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4482 /* expand_call should ensure this */
4483 if (arg
->offset
.var
|| GET_CODE (size_rtx
) != CONST_INT
)
4486 if (arg
->offset
.constant
> i
)
4488 if (arg
->offset
.constant
< i
+ INTVAL (size_rtx
))
4489 sibcall_failure
= 1;
4491 else if (arg
->offset
.constant
< i
)
4493 if (i
< arg
->offset
.constant
+ INTVAL (size_rtx
))
4494 sibcall_failure
= 1;
4499 /* Special handling is required if part of the parameter lies in the
4500 register parameter area. The argument may be copied into the stack
4501 slot using memcpy(), but the original contents of the register
4502 parameter area will be restored after the memcpy() call.
4504 To ensure that the part that lies in the register parameter area
4505 is copied correctly, we emit a separate push for that part. This
4506 push should be small enough to avoid a call to memcpy(). */
4507 #ifndef STACK_PARMS_IN_REG_PARM_AREA
4508 if (arg
->reg
&& arg
->pass_on_stack
)
4513 if (arg
->offset
.constant
< reg_parm_stack_space
&& arg
->offset
.var
)
4514 error ("variable offset is passed partially in stack and in reg");
4515 else if (arg
->offset
.constant
< reg_parm_stack_space
&& arg
->size
.var
)
4516 error ("variable size is passed partially in stack and in reg");
4517 else if (arg
->offset
.constant
< reg_parm_stack_space
4518 && ((arg
->offset
.constant
+ arg
->size
.constant
)
4519 > reg_parm_stack_space
))
4521 rtx size_rtx1
= GEN_INT (reg_parm_stack_space
- arg
->offset
.constant
);
4522 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx1
,
4523 TYPE_ALIGN (TREE_TYPE (pval
)), partial
, reg
,
4524 excess
, argblock
, ARGS_SIZE_RTX (arg
->offset
),
4525 reg_parm_stack_space
,
4526 ARGS_SIZE_RTX (arg
->alignment_pad
));
4531 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4532 TYPE_ALIGN (TREE_TYPE (pval
)), partial
, reg
, excess
,
4533 argblock
, ARGS_SIZE_RTX (arg
->offset
),
4534 reg_parm_stack_space
,
4535 ARGS_SIZE_RTX (arg
->alignment_pad
));
4538 /* Unless this is a partially-in-register argument, the argument is now
4541 ??? Note that this can change arg->value from arg->stack to
4542 arg->stack_slot and it matters when they are not the same.
4543 It isn't totally clear that this is correct in all cases. */
4545 arg
->value
= arg
->stack_slot
;
4547 /* Once we have pushed something, pops can't safely
4548 be deferred during the rest of the arguments. */
4551 /* ANSI doesn't require a sequence point here,
4552 but PCC has one, so this will avoid some problems. */
4555 /* Free any temporary slots made in processing this argument. Show
4556 that we might have taken the address of something and pushed that
4558 preserve_temp_slots (NULL_RTX
);
4562 return sibcall_failure
;