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
&& bytes
< UNITS_PER_WORD
)
1033 big_endian_correction
= (BITS_PER_WORD
- (bytes
* BITS_PER_UNIT
));
1035 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1037 rtx reg
= gen_reg_rtx (word_mode
);
1038 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
1039 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
1040 int bitalign
= TYPE_ALIGN (TREE_TYPE (args
[i
].tree_value
));
1042 args
[i
].aligned_regs
[j
] = reg
;
1044 /* There is no need to restrict this code to loading items
1045 in TYPE_ALIGN sized hunks. The bitfield instructions can
1046 load up entire word sized registers efficiently.
1048 ??? This may not be needed anymore.
1049 We use to emit a clobber here but that doesn't let later
1050 passes optimize the instructions we emit. By storing 0 into
1051 the register later passes know the first AND to zero out the
1052 bitfield being set in the register is unnecessary. The store
1053 of 0 will be deleted as will at least the first AND. */
1055 emit_move_insn (reg
, const0_rtx
);
1057 bytes
-= bitsize
/ BITS_PER_UNIT
;
1058 store_bit_field (reg
, bitsize
, big_endian_correction
, word_mode
,
1059 extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
1060 word_mode
, word_mode
, bitalign
,
1062 bitalign
, BITS_PER_WORD
);
1067 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1070 NUM_ACTUALS is the total number of parameters.
1072 N_NAMED_ARGS is the total number of named arguments.
1074 FNDECL is the tree code for the target of this call (if known)
1076 ARGS_SO_FAR holds state needed by the target to know where to place
1079 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1080 for arguments which are passed in registers.
1082 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1083 and may be modified by this routine.
1085 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1086 flags which may may be modified by this routine. */
1089 initialize_argument_information (num_actuals
, args
, args_size
, n_named_args
,
1090 actparms
, fndecl
, args_so_far
,
1091 reg_parm_stack_space
, old_stack_level
,
1092 old_pending_adj
, must_preallocate
,
1094 int num_actuals ATTRIBUTE_UNUSED
;
1095 struct arg_data
*args
;
1096 struct args_size
*args_size
;
1097 int n_named_args ATTRIBUTE_UNUSED
;
1100 CUMULATIVE_ARGS
*args_so_far
;
1101 int reg_parm_stack_space
;
1102 rtx
*old_stack_level
;
1103 int *old_pending_adj
;
1104 int *must_preallocate
;
1107 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1110 /* Count arg position in order args appear. */
1113 struct args_size alignment_pad
;
1117 args_size
->constant
= 0;
1120 /* In this loop, we consider args in the order they are written.
1121 We fill up ARGS from the front or from the back if necessary
1122 so that in any case the first arg to be pushed ends up at the front. */
1124 if (PUSH_ARGS_REVERSED
)
1126 i
= num_actuals
- 1, inc
= -1;
1127 /* In this case, must reverse order of args
1128 so that we compute and push the last arg first. */
1135 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1136 for (p
= actparms
, argpos
= 0; p
; p
= TREE_CHAIN (p
), i
+= inc
, argpos
++)
1138 tree type
= TREE_TYPE (TREE_VALUE (p
));
1140 enum machine_mode mode
;
1142 args
[i
].tree_value
= TREE_VALUE (p
);
1144 /* Replace erroneous argument with constant zero. */
1145 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
1146 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
1148 /* If TYPE is a transparent union, pass things the way we would
1149 pass the first field of the union. We have already verified that
1150 the modes are the same. */
1151 if (TREE_CODE (type
) == UNION_TYPE
&& TYPE_TRANSPARENT_UNION (type
))
1152 type
= TREE_TYPE (TYPE_FIELDS (type
));
1154 /* Decide where to pass this arg.
1156 args[i].reg is nonzero if all or part is passed in registers.
1158 args[i].partial is nonzero if part but not all is passed in registers,
1159 and the exact value says how many words are passed in registers.
1161 args[i].pass_on_stack is nonzero if the argument must at least be
1162 computed on the stack. It may then be loaded back into registers
1163 if args[i].reg is nonzero.
1165 These decisions are driven by the FUNCTION_... macros and must agree
1166 with those made by function.c. */
1168 /* See if this argument should be passed by invisible reference. */
1169 if ((TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1170 && contains_placeholder_p (TYPE_SIZE (type
)))
1171 || TREE_ADDRESSABLE (type
)
1172 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1173 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far
, TYPE_MODE (type
),
1174 type
, argpos
< n_named_args
)
1178 /* If we're compiling a thunk, pass through invisible
1179 references instead of making a copy. */
1180 if (current_function_is_thunk
1181 #ifdef FUNCTION_ARG_CALLEE_COPIES
1182 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far
, TYPE_MODE (type
),
1183 type
, argpos
< n_named_args
)
1184 /* If it's in a register, we must make a copy of it too. */
1185 /* ??? Is this a sufficient test? Is there a better one? */
1186 && !(TREE_CODE (args
[i
].tree_value
) == VAR_DECL
1187 && REG_P (DECL_RTL (args
[i
].tree_value
)))
1188 && ! TREE_ADDRESSABLE (type
))
1192 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1193 new object from the argument. If we are passing by
1194 invisible reference, the callee will do that for us, so we
1195 can strip off the TARGET_EXPR. This is not always safe,
1196 but it is safe in the only case where this is a useful
1197 optimization; namely, when the argument is a plain object.
1198 In that case, the frontend is just asking the backend to
1199 make a bitwise copy of the argument. */
1201 if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1202 && (DECL_P (TREE_OPERAND (args
[i
].tree_value
, 1)))
1203 && ! REG_P (DECL_RTL (TREE_OPERAND (args
[i
].tree_value
, 1))))
1204 args
[i
].tree_value
= TREE_OPERAND (args
[i
].tree_value
, 1);
1206 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1207 build_pointer_type (type
),
1208 args
[i
].tree_value
);
1209 type
= build_pointer_type (type
);
1213 /* We make a copy of the object and pass the address to the
1214 function being called. */
1217 if (!COMPLETE_TYPE_P (type
)
1218 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1219 || (flag_stack_check
&& ! STACK_CHECK_BUILTIN
1220 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type
),
1221 STACK_CHECK_MAX_VAR_SIZE
))))
1223 /* This is a variable-sized object. Make space on the stack
1225 rtx size_rtx
= expr_size (TREE_VALUE (p
));
1227 if (*old_stack_level
== 0)
1229 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1230 *old_pending_adj
= pending_stack_adjust
;
1231 pending_stack_adjust
= 0;
1234 copy
= gen_rtx_MEM (BLKmode
,
1235 allocate_dynamic_stack_space
1236 (size_rtx
, NULL_RTX
, TYPE_ALIGN (type
)));
1237 set_mem_attributes (copy
, type
, 1);
1240 copy
= assign_temp (type
, 0, 1, 0);
1242 store_expr (args
[i
].tree_value
, copy
, 0);
1243 *ecf_flags
&= ~(ECF_CONST
| ECF_PURE
);
1245 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1246 build_pointer_type (type
),
1247 make_tree (type
, copy
));
1248 type
= build_pointer_type (type
);
1252 mode
= TYPE_MODE (type
);
1253 unsignedp
= TREE_UNSIGNED (type
);
1255 #ifdef PROMOTE_FUNCTION_ARGS
1256 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
1259 args
[i
].unsignedp
= unsignedp
;
1260 args
[i
].mode
= mode
;
1262 args
[i
].reg
= FUNCTION_ARG (*args_so_far
, mode
, type
,
1263 argpos
< n_named_args
);
1264 #ifdef FUNCTION_INCOMING_ARG
1265 /* If this is a sibling call and the machine has register windows, the
1266 register window has to be unwinded before calling the routine, so
1267 arguments have to go into the incoming registers. */
1268 args
[i
].tail_call_reg
= FUNCTION_INCOMING_ARG (*args_so_far
, mode
, type
,
1269 argpos
< n_named_args
);
1271 args
[i
].tail_call_reg
= args
[i
].reg
;
1274 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1277 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far
, mode
, type
,
1278 argpos
< n_named_args
);
1281 args
[i
].pass_on_stack
= MUST_PASS_IN_STACK (mode
, type
);
1283 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1284 it means that we are to pass this arg in the register(s) designated
1285 by the PARALLEL, but also to pass it in the stack. */
1286 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1287 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1288 args
[i
].pass_on_stack
= 1;
1290 /* If this is an addressable type, we must preallocate the stack
1291 since we must evaluate the object into its final location.
1293 If this is to be passed in both registers and the stack, it is simpler
1295 if (TREE_ADDRESSABLE (type
)
1296 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1297 *must_preallocate
= 1;
1299 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1300 we cannot consider this function call constant. */
1301 if (TREE_ADDRESSABLE (type
))
1302 *ecf_flags
&= ~(ECF_CONST
| ECF_PURE
);
1304 /* Compute the stack-size of this argument. */
1305 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1306 || reg_parm_stack_space
> 0
1307 || args
[i
].pass_on_stack
)
1308 locate_and_pad_parm (mode
, type
,
1309 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1314 fndecl
, args_size
, &args
[i
].offset
,
1315 &args
[i
].size
, &alignment_pad
);
1317 #ifndef ARGS_GROW_DOWNWARD
1318 args
[i
].slot_offset
= *args_size
;
1321 args
[i
].alignment_pad
= alignment_pad
;
1323 /* If a part of the arg was put into registers,
1324 don't include that part in the amount pushed. */
1325 if (reg_parm_stack_space
== 0 && ! args
[i
].pass_on_stack
)
1326 args
[i
].size
.constant
-= ((args
[i
].partial
* UNITS_PER_WORD
)
1327 / (PARM_BOUNDARY
/ BITS_PER_UNIT
)
1328 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
1330 /* Update ARGS_SIZE, the total stack space for args so far. */
1332 args_size
->constant
+= args
[i
].size
.constant
;
1333 if (args
[i
].size
.var
)
1335 ADD_PARM_SIZE (*args_size
, args
[i
].size
.var
);
1338 /* Since the slot offset points to the bottom of the slot,
1339 we must record it after incrementing if the args grow down. */
1340 #ifdef ARGS_GROW_DOWNWARD
1341 args
[i
].slot_offset
= *args_size
;
1343 args
[i
].slot_offset
.constant
= -args_size
->constant
;
1345 SUB_PARM_SIZE (args
[i
].slot_offset
, args_size
->var
);
1348 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1349 have been used, etc. */
1351 FUNCTION_ARG_ADVANCE (*args_so_far
, TYPE_MODE (type
), type
,
1352 argpos
< n_named_args
);
1356 /* Update ARGS_SIZE to contain the total size for the argument block.
1357 Return the original constant component of the argument block's size.
1359 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1360 for arguments passed in registers. */
1363 compute_argument_block_size (reg_parm_stack_space
, args_size
,
1364 preferred_stack_boundary
)
1365 int reg_parm_stack_space
;
1366 struct args_size
*args_size
;
1367 int preferred_stack_boundary ATTRIBUTE_UNUSED
;
1369 int unadjusted_args_size
= args_size
->constant
;
1371 /* For accumulate outgoing args mode we don't need to align, since the frame
1372 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1373 backends from generating missaligned frame sizes. */
1374 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1375 preferred_stack_boundary
= STACK_BOUNDARY
;
1377 /* Compute the actual size of the argument block required. The variable
1378 and constant sizes must be combined, the size may have to be rounded,
1379 and there may be a minimum required size. */
1383 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1384 args_size
->constant
= 0;
1386 preferred_stack_boundary
/= BITS_PER_UNIT
;
1387 if (preferred_stack_boundary
> 1)
1389 /* We don't handle this case yet. To handle it correctly we have
1390 to add the delta, round and substract the delta.
1391 Currently no machine description requires this support. */
1392 if (stack_pointer_delta
& (preferred_stack_boundary
- 1))
1394 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1397 if (reg_parm_stack_space
> 0)
1400 = size_binop (MAX_EXPR
, args_size
->var
,
1401 ssize_int (reg_parm_stack_space
));
1403 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1404 /* The area corresponding to register parameters is not to count in
1405 the size of the block we need. So make the adjustment. */
1407 = size_binop (MINUS_EXPR
, args_size
->var
,
1408 ssize_int (reg_parm_stack_space
));
1414 preferred_stack_boundary
/= BITS_PER_UNIT
;
1415 if (preferred_stack_boundary
< 1)
1416 preferred_stack_boundary
= 1;
1417 args_size
->constant
= (((args_size
->constant
1418 + stack_pointer_delta
1419 + preferred_stack_boundary
- 1)
1420 / preferred_stack_boundary
1421 * preferred_stack_boundary
)
1422 - stack_pointer_delta
);
1424 args_size
->constant
= MAX (args_size
->constant
,
1425 reg_parm_stack_space
);
1427 #ifdef MAYBE_REG_PARM_STACK_SPACE
1428 if (reg_parm_stack_space
== 0)
1429 args_size
->constant
= 0;
1432 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1433 args_size
->constant
-= reg_parm_stack_space
;
1436 return unadjusted_args_size
;
1439 /* Precompute parameters as needed for a function call.
1441 FLAGS is mask of ECF_* constants.
1443 NUM_ACTUALS is the number of arguments.
1445 ARGS is an array containing information for each argument; this
1446 routine fills in the INITIAL_VALUE and VALUE fields for each
1447 precomputed argument. */
1450 precompute_arguments (flags
, num_actuals
, args
)
1453 struct arg_data
*args
;
1457 /* If this function call is cse'able, precompute all the parameters.
1458 Note that if the parameter is constructed into a temporary, this will
1459 cause an additional copy because the parameter will be constructed
1460 into a temporary location and then copied into the outgoing arguments.
1461 If a parameter contains a call to alloca and this function uses the
1462 stack, precompute the parameter. */
1464 /* If we preallocated the stack space, and some arguments must be passed
1465 on the stack, then we must precompute any parameter which contains a
1466 function call which will store arguments on the stack.
1467 Otherwise, evaluating the parameter may clobber previous parameters
1468 which have already been stored into the stack. (we have code to avoid
1469 such case by saving the ougoing stack arguments, but it results in
1472 for (i
= 0; i
< num_actuals
; i
++)
1473 if ((flags
& (ECF_CONST
| ECF_PURE
))
1474 || calls_function (args
[i
].tree_value
, !ACCUMULATE_OUTGOING_ARGS
))
1476 enum machine_mode mode
;
1478 /* If this is an addressable type, we cannot pre-evaluate it. */
1479 if (TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
)))
1485 = expand_expr (args
[i
].tree_value
, NULL_RTX
, VOIDmode
, 0);
1487 preserve_temp_slots (args
[i
].value
);
1490 /* ANSI doesn't require a sequence point here,
1491 but PCC has one, so this will avoid some problems. */
1494 args
[i
].initial_value
= args
[i
].value
1495 = protect_from_queue (args
[i
].value
, 0);
1497 mode
= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
));
1498 if (mode
!= args
[i
].mode
)
1501 = convert_modes (args
[i
].mode
, mode
,
1502 args
[i
].value
, args
[i
].unsignedp
);
1503 #ifdef PROMOTE_FOR_CALL_ONLY
1504 /* CSE will replace this only if it contains args[i].value
1505 pseudo, so convert it down to the declared mode using
1507 if (GET_CODE (args
[i
].value
) == REG
1508 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
)
1510 args
[i
].initial_value
1511 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1512 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1513 SUBREG_PROMOTED_UNSIGNED_P (args
[i
].initial_value
)
1514 = args
[i
].unsignedp
;
1521 /* Given the current state of MUST_PREALLOCATE and information about
1522 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1523 compute and return the final value for MUST_PREALLOCATE. */
1526 finalize_must_preallocate (must_preallocate
, num_actuals
, args
, args_size
)
1527 int must_preallocate
;
1529 struct arg_data
*args
;
1530 struct args_size
*args_size
;
1532 /* See if we have or want to preallocate stack space.
1534 If we would have to push a partially-in-regs parm
1535 before other stack parms, preallocate stack space instead.
1537 If the size of some parm is not a multiple of the required stack
1538 alignment, we must preallocate.
1540 If the total size of arguments that would otherwise create a copy in
1541 a temporary (such as a CALL) is more than half the total argument list
1542 size, preallocation is faster.
1544 Another reason to preallocate is if we have a machine (like the m88k)
1545 where stack alignment is required to be maintained between every
1546 pair of insns, not just when the call is made. However, we assume here
1547 that such machines either do not have push insns (and hence preallocation
1548 would occur anyway) or the problem is taken care of with
1551 if (! must_preallocate
)
1553 int partial_seen
= 0;
1554 int copy_to_evaluate_size
= 0;
1557 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1559 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1561 else if (partial_seen
&& args
[i
].reg
== 0)
1562 must_preallocate
= 1;
1564 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1565 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1566 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1567 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1568 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1569 copy_to_evaluate_size
1570 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1573 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1574 && args_size
->constant
> 0)
1575 must_preallocate
= 1;
1577 return must_preallocate
;
1580 /* If we preallocated stack space, compute the address of each argument
1581 and store it into the ARGS array.
1583 We need not ensure it is a valid memory address here; it will be
1584 validized when it is used.
1586 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1589 compute_argument_addresses (args
, argblock
, num_actuals
)
1590 struct arg_data
*args
;
1596 rtx arg_reg
= argblock
;
1597 int i
, arg_offset
= 0;
1599 if (GET_CODE (argblock
) == PLUS
)
1600 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1602 for (i
= 0; i
< num_actuals
; i
++)
1604 rtx offset
= ARGS_SIZE_RTX (args
[i
].offset
);
1605 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].slot_offset
);
1608 /* Skip this parm if it will not be passed on the stack. */
1609 if (! args
[i
].pass_on_stack
&& args
[i
].reg
!= 0)
1612 if (GET_CODE (offset
) == CONST_INT
)
1613 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1615 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1617 addr
= plus_constant (addr
, arg_offset
);
1618 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1619 set_mem_attributes (args
[i
].stack
,
1620 TREE_TYPE (args
[i
].tree_value
), 1);
1622 if (GET_CODE (slot_offset
) == CONST_INT
)
1623 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1625 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1627 addr
= plus_constant (addr
, arg_offset
);
1628 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1629 set_mem_attributes (args
[i
].stack_slot
,
1630 TREE_TYPE (args
[i
].tree_value
), 1);
1632 /* Function incoming arguments may overlap with sibling call
1633 outgoing arguments and we cannot allow reordering of reads
1634 from function arguments with stores to outgoing arguments
1635 of sibling calls. */
1636 set_mem_alias_set (args
[i
].stack
, 0);
1637 set_mem_alias_set (args
[i
].stack_slot
, 0);
1642 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1643 in a call instruction.
1645 FNDECL is the tree node for the target function. For an indirect call
1646 FNDECL will be NULL_TREE.
1648 EXP is the CALL_EXPR for this call. */
1651 rtx_for_function_call (fndecl
, exp
)
1657 /* Get the function to call, in the form of RTL. */
1660 /* If this is the first use of the function, see if we need to
1661 make an external definition for it. */
1662 if (! TREE_USED (fndecl
))
1664 assemble_external (fndecl
);
1665 TREE_USED (fndecl
) = 1;
1668 /* Get a SYMBOL_REF rtx for the function address. */
1669 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1672 /* Generate an rtx (probably a pseudo-register) for the address. */
1677 = expand_expr (TREE_OPERAND (exp
, 0), NULL_RTX
, VOIDmode
, 0);
1678 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1680 /* Check the function is executable. */
1681 if (current_function_check_memory_usage
)
1683 #ifdef POINTERS_EXTEND_UNSIGNED
1684 if (GET_MODE (funexp
) != ptr_mode
)
1685 funaddr
= convert_memory_address (ptr_mode
, funexp
);
1687 emit_library_call (chkr_check_exec_libfunc
, LCT_CONST_MAKE_BLOCK
,
1688 VOIDmode
, 1, funaddr
, ptr_mode
);
1695 /* Do the register loads required for any wholly-register parms or any
1696 parms which are passed both on the stack and in a register. Their
1697 expressions were already evaluated.
1699 Mark all register-parms as living through the call, putting these USE
1700 insns in the CALL_INSN_FUNCTION_USAGE field. */
1703 load_register_parameters (args
, num_actuals
, call_fusage
, flags
)
1704 struct arg_data
*args
;
1711 #ifdef LOAD_ARGS_REVERSED
1712 for (i
= num_actuals
- 1; i
>= 0; i
--)
1714 for (i
= 0; i
< num_actuals
; i
++)
1717 rtx reg
= ((flags
& ECF_SIBCALL
)
1718 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1719 int partial
= args
[i
].partial
;
1724 /* Set to non-negative if must move a word at a time, even if just
1725 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1726 we just use a normal move insn. This value can be zero if the
1727 argument is a zero size structure with no fields. */
1728 nregs
= (partial
? partial
1729 : (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1730 ? ((int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
))
1731 + (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
)
1734 /* Handle calls that pass values in multiple non-contiguous
1735 locations. The Irix 6 ABI has examples of this. */
1737 if (GET_CODE (reg
) == PARALLEL
)
1738 emit_group_load (reg
, args
[i
].value
,
1739 int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
)),
1740 TYPE_ALIGN (TREE_TYPE (args
[i
].tree_value
)));
1742 /* If simple case, just do move. If normal partial, store_one_arg
1743 has already loaded the register for us. In all other cases,
1744 load the register(s) from memory. */
1746 else if (nregs
== -1)
1747 emit_move_insn (reg
, args
[i
].value
);
1749 /* If we have pre-computed the values to put in the registers in
1750 the case of non-aligned structures, copy them in now. */
1752 else if (args
[i
].n_aligned_regs
!= 0)
1753 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1754 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1755 args
[i
].aligned_regs
[j
]);
1757 else if (partial
== 0 || args
[i
].pass_on_stack
)
1758 move_block_to_reg (REGNO (reg
),
1759 validize_mem (args
[i
].value
), nregs
,
1762 /* Handle calls that pass values in multiple non-contiguous
1763 locations. The Irix 6 ABI has examples of this. */
1764 if (GET_CODE (reg
) == PARALLEL
)
1765 use_group_regs (call_fusage
, reg
);
1766 else if (nregs
== -1)
1767 use_reg (call_fusage
, reg
);
1769 use_regs (call_fusage
, REGNO (reg
), nregs
== 0 ? 1 : nregs
);
1774 /* Try to integrate function. See expand_inline_function for documentation
1775 about the parameters. */
1778 try_to_integrate (fndecl
, actparms
, target
, ignore
, type
, structure_value_addr
)
1784 rtx structure_value_addr
;
1789 rtx old_stack_level
= 0;
1790 int reg_parm_stack_space
= 0;
1792 #ifdef REG_PARM_STACK_SPACE
1793 #ifdef MAYBE_REG_PARM_STACK_SPACE
1794 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
1796 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
1800 before_call
= get_last_insn ();
1802 timevar_push (TV_INTEGRATION
);
1804 temp
= expand_inline_function (fndecl
, actparms
, target
,
1806 structure_value_addr
);
1808 timevar_pop (TV_INTEGRATION
);
1810 /* If inlining succeeded, return. */
1811 if (temp
!= (rtx
) (HOST_WIDE_INT
) - 1)
1813 if (ACCUMULATE_OUTGOING_ARGS
)
1815 /* If the outgoing argument list must be preserved, push
1816 the stack before executing the inlined function if it
1819 for (i
= reg_parm_stack_space
- 1; i
>= 0; i
--)
1820 if (i
< highest_outgoing_arg_in_use
&& stack_usage_map
[i
] != 0)
1823 if (stack_arg_under_construction
|| i
>= 0)
1826 = before_call
? NEXT_INSN (before_call
) : get_insns ();
1827 rtx insn
= NULL_RTX
, seq
;
1829 /* Look for a call in the inline function code.
1830 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1831 nonzero then there is a call and it is not necessary
1832 to scan the insns. */
1834 if (DECL_SAVED_INSNS (fndecl
)->outgoing_args_size
== 0)
1835 for (insn
= first_insn
; insn
; insn
= NEXT_INSN (insn
))
1836 if (GET_CODE (insn
) == CALL_INSN
)
1841 /* Reserve enough stack space so that the largest
1842 argument list of any function call in the inline
1843 function does not overlap the argument list being
1844 evaluated. This is usually an overestimate because
1845 allocate_dynamic_stack_space reserves space for an
1846 outgoing argument list in addition to the requested
1847 space, but there is no way to ask for stack space such
1848 that an argument list of a certain length can be
1851 Add the stack space reserved for register arguments, if
1852 any, in the inline function. What is really needed is the
1853 largest value of reg_parm_stack_space in the inline
1854 function, but that is not available. Using the current
1855 value of reg_parm_stack_space is wrong, but gives
1856 correct results on all supported machines. */
1858 int adjust
= (DECL_SAVED_INSNS (fndecl
)->outgoing_args_size
1859 + reg_parm_stack_space
);
1862 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
1863 allocate_dynamic_stack_space (GEN_INT (adjust
),
1864 NULL_RTX
, BITS_PER_UNIT
);
1867 emit_insns_before (seq
, first_insn
);
1868 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1873 /* If the result is equivalent to TARGET, return TARGET to simplify
1874 checks in store_expr. They can be equivalent but not equal in the
1875 case of a function that returns BLKmode. */
1876 if (temp
!= target
&& rtx_equal_p (temp
, target
))
1881 /* If inlining failed, mark FNDECL as needing to be compiled
1882 separately after all. If function was declared inline,
1884 if (DECL_INLINE (fndecl
) && warn_inline
&& !flag_no_inline
1885 && optimize
> 0 && !TREE_ADDRESSABLE (fndecl
))
1887 warning_with_decl (fndecl
, "inlining failed in call to `%s'");
1888 warning ("called from here");
1890 mark_addressable (fndecl
);
1891 return (rtx
) (HOST_WIDE_INT
) - 1;
1894 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1895 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1896 bytes, then we would need to push some additional bytes to pad the
1897 arguments. So, we compute an adjust to the stack pointer for an
1898 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1899 bytes. Then, when the arguments are pushed the stack will be perfectly
1900 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1901 be popped after the call. Returns the adjustment. */
1904 combine_pending_stack_adjustment_and_call (unadjusted_args_size
,
1906 preferred_unit_stack_boundary
)
1907 int unadjusted_args_size
;
1908 struct args_size
*args_size
;
1909 int preferred_unit_stack_boundary
;
1911 /* The number of bytes to pop so that the stack will be
1912 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1913 HOST_WIDE_INT adjustment
;
1914 /* The alignment of the stack after the arguments are pushed, if we
1915 just pushed the arguments without adjust the stack here. */
1916 HOST_WIDE_INT unadjusted_alignment
;
1918 unadjusted_alignment
1919 = ((stack_pointer_delta
+ unadjusted_args_size
)
1920 % preferred_unit_stack_boundary
);
1922 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1923 as possible -- leaving just enough left to cancel out the
1924 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1925 PENDING_STACK_ADJUST is non-negative, and congruent to
1926 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1928 /* Begin by trying to pop all the bytes. */
1929 unadjusted_alignment
1930 = (unadjusted_alignment
1931 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1932 adjustment
= pending_stack_adjust
;
1933 /* Push enough additional bytes that the stack will be aligned
1934 after the arguments are pushed. */
1935 if (preferred_unit_stack_boundary
> 1)
1937 if (unadjusted_alignment
> 0)
1938 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1940 adjustment
+= unadjusted_alignment
;
1943 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1944 bytes after the call. The right number is the entire
1945 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1946 by the arguments in the first place. */
1948 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1953 /* Scan X expression if it does not dereference any argument slots
1954 we already clobbered by tail call arguments (as noted in stored_args_map
1956 Return non-zero if X expression dereferences such argument slots,
1960 check_sibcall_argument_overlap_1 (x
)
1971 code
= GET_CODE (x
);
1975 if (XEXP (x
, 0) == current_function_internal_arg_pointer
)
1977 else if (GET_CODE (XEXP (x
, 0)) == PLUS
1978 && XEXP (XEXP (x
, 0), 0) ==
1979 current_function_internal_arg_pointer
1980 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
)
1981 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
1985 #ifdef ARGS_GROW_DOWNWARD
1986 i
= -i
- GET_MODE_SIZE (GET_MODE (x
));
1989 for (k
= 0; k
< GET_MODE_SIZE (GET_MODE (x
)); k
++)
1990 if (i
+ k
< stored_args_map
->n_bits
1991 && TEST_BIT (stored_args_map
, i
+ k
))
1997 /* Scan all subexpressions. */
1998 fmt
= GET_RTX_FORMAT (code
);
1999 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
2003 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
2006 else if (*fmt
== 'E')
2008 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2009 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
2016 /* Scan sequence after INSN if it does not dereference any argument slots
2017 we already clobbered by tail call arguments (as noted in stored_args_map
2018 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2019 Return non-zero if sequence after INSN dereferences such argument slots,
2023 check_sibcall_argument_overlap (insn
, arg
)
2025 struct arg_data
*arg
;
2029 if (insn
== NULL_RTX
)
2030 insn
= get_insns ();
2032 insn
= NEXT_INSN (insn
);
2034 for (; insn
; insn
= NEXT_INSN (insn
))
2036 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
2039 #ifdef ARGS_GROW_DOWNWARD
2040 low
= -arg
->offset
.constant
- arg
->size
.constant
;
2042 low
= arg
->offset
.constant
;
2045 for (high
= low
+ arg
->size
.constant
; low
< high
; low
++)
2046 SET_BIT (stored_args_map
, low
);
2047 return insn
!= NULL_RTX
;
2050 /* Generate all the code for a function call
2051 and return an rtx for its value.
2052 Store the value in TARGET (specified as an rtx) if convenient.
2053 If the value is stored in TARGET then TARGET is returned.
2054 If IGNORE is nonzero, then we ignore the value of the function call. */
2057 expand_call (exp
, target
, ignore
)
2062 /* Nonzero if we are currently expanding a call. */
2063 static int currently_expanding_call
= 0;
2065 /* List of actual parameters. */
2066 tree actparms
= TREE_OPERAND (exp
, 1);
2067 /* RTX for the function to be called. */
2069 /* Sequence of insns to perform a tail recursive "call". */
2070 rtx tail_recursion_insns
= NULL_RTX
;
2071 /* Sequence of insns to perform a normal "call". */
2072 rtx normal_call_insns
= NULL_RTX
;
2073 /* Sequence of insns to perform a tail recursive "call". */
2074 rtx tail_call_insns
= NULL_RTX
;
2075 /* Data type of the function. */
2077 /* Declaration of the function being called,
2078 or 0 if the function is computed (not known by name). */
2081 int try_tail_call
= 1;
2082 int try_tail_recursion
= 1;
2085 /* Register in which non-BLKmode value will be returned,
2086 or 0 if no value or if value is BLKmode. */
2088 /* Address where we should return a BLKmode value;
2089 0 if value not BLKmode. */
2090 rtx structure_value_addr
= 0;
2091 /* Nonzero if that address is being passed by treating it as
2092 an extra, implicit first parameter. Otherwise,
2093 it is passed by being copied directly into struct_value_rtx. */
2094 int structure_value_addr_parm
= 0;
2095 /* Size of aggregate value wanted, or zero if none wanted
2096 or if we are using the non-reentrant PCC calling convention
2097 or expecting the value in registers. */
2098 HOST_WIDE_INT struct_value_size
= 0;
2099 /* Nonzero if called function returns an aggregate in memory PCC style,
2100 by returning the address of where to find it. */
2101 int pcc_struct_value
= 0;
2103 /* Number of actual parameters in this call, including struct value addr. */
2105 /* Number of named args. Args after this are anonymous ones
2106 and they must all go on the stack. */
2109 /* Vector of information about each argument.
2110 Arguments are numbered in the order they will be pushed,
2111 not the order they are written. */
2112 struct arg_data
*args
;
2114 /* Total size in bytes of all the stack-parms scanned so far. */
2115 struct args_size args_size
;
2116 struct args_size adjusted_args_size
;
2117 /* Size of arguments before any adjustments (such as rounding). */
2118 int unadjusted_args_size
;
2119 /* Data on reg parms scanned so far. */
2120 CUMULATIVE_ARGS args_so_far
;
2121 /* Nonzero if a reg parm has been scanned. */
2123 /* Nonzero if this is an indirect function call. */
2125 /* Nonzero if we must avoid push-insns in the args for this call.
2126 If stack space is allocated for register parameters, but not by the
2127 caller, then it is preallocated in the fixed part of the stack frame.
2128 So the entire argument block must then be preallocated (i.e., we
2129 ignore PUSH_ROUNDING in that case). */
2131 int must_preallocate
= !PUSH_ARGS
;
2133 /* Size of the stack reserved for parameter registers. */
2134 int reg_parm_stack_space
= 0;
2136 /* Address of space preallocated for stack parms
2137 (on machines that lack push insns), or 0 if space not preallocated. */
2140 /* Mask of ECF_ flags. */
2142 /* Nonzero if this is a call to an inline function. */
2143 int is_integrable
= 0;
2144 #ifdef REG_PARM_STACK_SPACE
2145 /* Define the boundary of the register parm stack space that needs to be
2147 int low_to_save
= -1, high_to_save
;
2148 rtx save_area
= 0; /* Place that it is saved */
2151 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
2152 char *initial_stack_usage_map
= stack_usage_map
;
2153 int old_stack_arg_under_construction
= 0;
2155 rtx old_stack_level
= 0;
2156 int old_pending_adj
= 0;
2157 int old_inhibit_defer_pop
= inhibit_defer_pop
;
2158 int old_stack_allocated
;
2160 tree p
= TREE_OPERAND (exp
, 0);
2162 /* The alignment of the stack, in bits. */
2163 HOST_WIDE_INT preferred_stack_boundary
;
2164 /* The alignment of the stack, in bytes. */
2165 HOST_WIDE_INT preferred_unit_stack_boundary
;
2167 /* The value of the function call can be put in a hard register. But
2168 if -fcheck-memory-usage, code which invokes functions (and thus
2169 damages some hard registers) can be inserted before using the value.
2170 So, target is always a pseudo-register in that case. */
2171 if (current_function_check_memory_usage
)
2174 /* See if this is "nothrow" function call. */
2175 if (TREE_NOTHROW (exp
))
2176 flags
|= ECF_NOTHROW
;
2178 /* See if we can find a DECL-node for the actual function.
2179 As a result, decide whether this is a call to an integrable function. */
2181 fndecl
= get_callee_fndecl (exp
);
2185 && fndecl
!= current_function_decl
2186 && DECL_INLINE (fndecl
)
2187 && DECL_SAVED_INSNS (fndecl
)
2188 && DECL_SAVED_INSNS (fndecl
)->inlinable
)
2190 else if (! TREE_ADDRESSABLE (fndecl
))
2192 /* In case this function later becomes inlinable,
2193 record that there was already a non-inline call to it.
2195 Use abstraction instead of setting TREE_ADDRESSABLE
2197 if (DECL_INLINE (fndecl
) && warn_inline
&& !flag_no_inline
2200 warning_with_decl (fndecl
, "can't inline call to `%s'");
2201 warning ("called from here");
2203 mark_addressable (fndecl
);
2206 flags
|= flags_from_decl_or_type (fndecl
);
2209 /* If we don't have specific function to call, see if we have a
2210 attributes set in the type. */
2212 flags
|= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p
)));
2214 /* Mark if the function returns with the stack pointer depressed. */
2215 if (TREE_CODE (TREE_TYPE (TREE_TYPE (p
))) == FUNCTION_TYPE
2216 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (TREE_TYPE (p
))))
2218 flags
|= ECF_SP_DEPRESSED
;
2219 flags
&= ~(ECF_PURE
| ECF_CONST
);
2222 #ifdef REG_PARM_STACK_SPACE
2223 #ifdef MAYBE_REG_PARM_STACK_SPACE
2224 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
2226 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
2230 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2231 if (reg_parm_stack_space
> 0 && PUSH_ARGS
)
2232 must_preallocate
= 1;
2235 /* Warn if this value is an aggregate type,
2236 regardless of which calling convention we are using for it. */
2237 if (warn_aggregate_return
&& AGGREGATE_TYPE_P (TREE_TYPE (exp
)))
2238 warning ("function call has aggregate value");
2240 /* Set up a place to return a structure. */
2242 /* Cater to broken compilers. */
2243 if (aggregate_value_p (exp
))
2245 /* This call returns a big structure. */
2246 flags
&= ~(ECF_CONST
| ECF_PURE
);
2248 #ifdef PCC_STATIC_STRUCT_RETURN
2250 pcc_struct_value
= 1;
2251 /* Easier than making that case work right. */
2254 /* In case this is a static function, note that it has been
2256 if (! TREE_ADDRESSABLE (fndecl
))
2257 mark_addressable (fndecl
);
2261 #else /* not PCC_STATIC_STRUCT_RETURN */
2263 struct_value_size
= int_size_in_bytes (TREE_TYPE (exp
));
2265 if (target
&& GET_CODE (target
) == MEM
)
2266 structure_value_addr
= XEXP (target
, 0);
2269 /* For variable-sized objects, we must be called with a target
2270 specified. If we were to allocate space on the stack here,
2271 we would have no way of knowing when to free it. */
2272 rtx d
= assign_temp (TREE_TYPE (exp
), 1, 1, 1);
2274 mark_temp_addr_taken (d
);
2275 structure_value_addr
= XEXP (d
, 0);
2279 #endif /* not PCC_STATIC_STRUCT_RETURN */
2282 /* If called function is inline, try to integrate it. */
2286 rtx temp
= try_to_integrate (fndecl
, actparms
, target
,
2287 ignore
, TREE_TYPE (exp
),
2288 structure_value_addr
);
2289 if (temp
!= (rtx
) (HOST_WIDE_INT
) - 1)
2293 /* Figure out the amount to which the stack should be aligned. */
2294 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2296 /* Operand 0 is a pointer-to-function; get the type of the function. */
2297 funtype
= TREE_TYPE (TREE_OPERAND (exp
, 0));
2298 if (! POINTER_TYPE_P (funtype
))
2300 funtype
= TREE_TYPE (funtype
);
2302 /* See if this is a call to a function that can return more than once
2303 or a call to longjmp or malloc. */
2304 flags
|= special_function_p (fndecl
, flags
);
2306 if (flags
& ECF_MAY_BE_ALLOCA
)
2307 current_function_calls_alloca
= 1;
2309 /* If struct_value_rtx is 0, it means pass the address
2310 as if it were an extra parameter. */
2311 if (structure_value_addr
&& struct_value_rtx
== 0)
2313 /* If structure_value_addr is a REG other than
2314 virtual_outgoing_args_rtx, we can use always use it. If it
2315 is not a REG, we must always copy it into a register.
2316 If it is virtual_outgoing_args_rtx, we must copy it to another
2317 register in some cases. */
2318 rtx temp
= (GET_CODE (structure_value_addr
) != REG
2319 || (ACCUMULATE_OUTGOING_ARGS
2320 && stack_arg_under_construction
2321 && structure_value_addr
== virtual_outgoing_args_rtx
)
2322 ? copy_addr_to_reg (structure_value_addr
)
2323 : structure_value_addr
);
2326 = tree_cons (error_mark_node
,
2327 make_tree (build_pointer_type (TREE_TYPE (funtype
)),
2330 structure_value_addr_parm
= 1;
2333 /* Count the arguments and set NUM_ACTUALS. */
2334 for (p
= actparms
, num_actuals
= 0; p
; p
= TREE_CHAIN (p
))
2337 /* Compute number of named args.
2338 Normally, don't include the last named arg if anonymous args follow.
2339 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2340 (If no anonymous args follow, the result of list_length is actually
2341 one too large. This is harmless.)
2343 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2344 zero, this machine will be able to place unnamed args that were
2345 passed in registers into the stack. So treat all args as named.
2346 This allows the insns emitting for a specific argument list to be
2347 independent of the function declaration.
2349 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2350 reliable way to pass unnamed args in registers, so we must force
2351 them into memory. */
2353 if ((STRICT_ARGUMENT_NAMING
2354 || ! PRETEND_OUTGOING_VARARGS_NAMED
)
2355 && TYPE_ARG_TYPES (funtype
) != 0)
2357 = (list_length (TYPE_ARG_TYPES (funtype
))
2358 /* Don't include the last named arg. */
2359 - (STRICT_ARGUMENT_NAMING
? 0 : 1)
2360 /* Count the struct value address, if it is passed as a parm. */
2361 + structure_value_addr_parm
);
2363 /* If we know nothing, treat all args as named. */
2364 n_named_args
= num_actuals
;
2366 /* Start updating where the next arg would go.
2368 On some machines (such as the PA) indirect calls have a different
2369 calling convention than normal calls. The last argument in
2370 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2372 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, (fndecl
== 0));
2374 /* Make a vector to hold all the information about each arg. */
2375 args
= (struct arg_data
*) alloca (num_actuals
* sizeof (struct arg_data
));
2376 memset ((char *) args
, 0, num_actuals
* sizeof (struct arg_data
));
2378 /* Build up entries in the ARGS array, compute the size of the
2379 arguments into ARGS_SIZE, etc. */
2380 initialize_argument_information (num_actuals
, args
, &args_size
,
2381 n_named_args
, actparms
, fndecl
,
2382 &args_so_far
, reg_parm_stack_space
,
2383 &old_stack_level
, &old_pending_adj
,
2384 &must_preallocate
, &flags
);
2388 /* If this function requires a variable-sized argument list, don't
2389 try to make a cse'able block for this call. We may be able to
2390 do this eventually, but it is too complicated to keep track of
2391 what insns go in the cse'able block and which don't. */
2393 flags
&= ~(ECF_CONST
| ECF_PURE
);
2394 must_preallocate
= 1;
2397 /* Now make final decision about preallocating stack space. */
2398 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2402 /* If the structure value address will reference the stack pointer, we
2403 must stabilize it. We don't need to do this if we know that we are
2404 not going to adjust the stack pointer in processing this call. */
2406 if (structure_value_addr
2407 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2408 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2409 structure_value_addr
))
2411 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2412 structure_value_addr
= copy_to_reg (structure_value_addr
);
2414 /* Tail calls can make things harder to debug, and we're traditionally
2415 pushed these optimizations into -O2. Don't try if we're already
2416 expanding a call, as that means we're an argument. Don't try if
2417 there's cleanups, as we know there's code to follow the call.
2419 If rtx_equal_function_value_matters is false, that means we've
2420 finished with regular parsing. Which means that some of the
2421 machinery we use to generate tail-calls is no longer in place.
2422 This is most often true of sjlj-exceptions, which we couldn't
2423 tail-call to anyway. */
2425 if (currently_expanding_call
++ != 0
2426 || !flag_optimize_sibling_calls
2427 || !rtx_equal_function_value_matters
2428 || any_pending_cleanups (1)
2430 try_tail_call
= try_tail_recursion
= 0;
2432 /* Tail recursion fails, when we are not dealing with recursive calls. */
2433 if (!try_tail_recursion
2434 || TREE_CODE (TREE_OPERAND (exp
, 0)) != ADDR_EXPR
2435 || TREE_OPERAND (TREE_OPERAND (exp
, 0), 0) != current_function_decl
)
2436 try_tail_recursion
= 0;
2438 /* Rest of purposes for tail call optimizations to fail. */
2440 #ifdef HAVE_sibcall_epilogue
2441 !HAVE_sibcall_epilogue
2446 /* Doing sibling call optimization needs some work, since
2447 structure_value_addr can be allocated on the stack.
2448 It does not seem worth the effort since few optimizable
2449 sibling calls will return a structure. */
2450 || structure_value_addr
!= NULL_RTX
2451 /* If the register holding the address is a callee saved
2452 register, then we lose. We have no way to prevent that,
2453 so we only allow calls to named functions. */
2454 /* ??? This could be done by having the insn constraints
2455 use a register class that is all call-clobbered. Any
2456 reload insns generated to fix things up would appear
2457 before the sibcall_epilogue. */
2458 || fndecl
== NULL_TREE
2459 || (flags
& (ECF_RETURNS_TWICE
| ECF_LONGJMP
))
2460 || TREE_THIS_VOLATILE (fndecl
)
2461 || !FUNCTION_OK_FOR_SIBCALL (fndecl
)
2462 /* If this function requires more stack slots than the current
2463 function, we cannot change it into a sibling call. */
2464 || args_size
.constant
> current_function_args_size
2465 /* If the callee pops its own arguments, then it must pop exactly
2466 the same number of arguments as the current function. */
2467 || RETURN_POPS_ARGS (fndecl
, funtype
, args_size
.constant
)
2468 != RETURN_POPS_ARGS (current_function_decl
,
2469 TREE_TYPE (current_function_decl
),
2470 current_function_args_size
))
2473 if (try_tail_call
|| try_tail_recursion
)
2476 actparms
= NULL_TREE
;
2477 /* Ok, we're going to give the tail call the old college try.
2478 This means we're going to evaluate the function arguments
2479 up to three times. There are two degrees of badness we can
2480 encounter, those that can be unsaved and those that can't.
2481 (See unsafe_for_reeval commentary for details.)
2483 Generate a new argument list. Pass safe arguments through
2484 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2485 For hard badness, evaluate them now and put their resulting
2486 rtx in a temporary VAR_DECL.
2488 initialize_argument_information has ordered the array for the
2489 order to be pushed, and we must remember this when reconstructing
2490 the original argument orde. */
2492 if (PUSH_ARGS_REVERSED
)
2501 i
= num_actuals
- 1;
2505 for (; i
!= end
; i
+= inc
)
2507 switch (unsafe_for_reeval (args
[i
].tree_value
))
2512 case 1: /* Mildly unsafe. */
2513 args
[i
].tree_value
= unsave_expr (args
[i
].tree_value
);
2516 case 2: /* Wildly unsafe. */
2518 tree var
= build_decl (VAR_DECL
, NULL_TREE
,
2519 TREE_TYPE (args
[i
].tree_value
));
2521 expand_expr (args
[i
].tree_value
, NULL_RTX
,
2522 VOIDmode
, EXPAND_NORMAL
));
2523 args
[i
].tree_value
= var
;
2530 /* We need to build actparms for optimize_tail_recursion. We can
2531 safely trash away TREE_PURPOSE, since it is unused by this
2533 if (try_tail_recursion
)
2534 actparms
= tree_cons (NULL_TREE
, args
[i
].tree_value
, actparms
);
2536 /* Expanding one of those dangerous arguments could have added
2537 cleanups, but otherwise give it a whirl. */
2538 if (any_pending_cleanups (1))
2539 try_tail_call
= try_tail_recursion
= 0;
2542 /* Generate a tail recursion sequence when calling ourselves. */
2544 if (try_tail_recursion
)
2546 /* We want to emit any pending stack adjustments before the tail
2547 recursion "call". That way we know any adjustment after the tail
2548 recursion call can be ignored if we indeed use the tail recursion
2550 int save_pending_stack_adjust
= pending_stack_adjust
;
2551 int save_stack_pointer_delta
= stack_pointer_delta
;
2553 /* Emit any queued insns now; otherwise they would end up in
2554 only one of the alternates. */
2557 /* Use a new sequence to hold any RTL we generate. We do not even
2558 know if we will use this RTL yet. The final decision can not be
2559 made until after RTL generation for the entire function is
2562 /* If expanding any of the arguments creates cleanups, we can't
2563 do a tailcall. So, we'll need to pop the pending cleanups
2564 list. If, however, all goes well, and there are no cleanups
2565 then the call to expand_start_target_temps will have no
2567 expand_start_target_temps ();
2568 if (optimize_tail_recursion (actparms
, get_last_insn ()))
2570 if (any_pending_cleanups (1))
2571 try_tail_call
= try_tail_recursion
= 0;
2573 tail_recursion_insns
= get_insns ();
2575 expand_end_target_temps ();
2578 /* Restore the original pending stack adjustment for the sibling and
2579 normal call cases below. */
2580 pending_stack_adjust
= save_pending_stack_adjust
;
2581 stack_pointer_delta
= save_stack_pointer_delta
;
2584 if (profile_arc_flag
&& (flags
& ECF_FORK_OR_EXEC
))
2586 /* A fork duplicates the profile information, and an exec discards
2587 it. We can't rely on fork/exec to be paired. So write out the
2588 profile information we have gathered so far, and clear it. */
2589 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2590 is subject to race conditions, just as with multithreaded
2593 emit_library_call (gen_rtx_SYMBOL_REF (Pmode
, "__bb_fork_func"),
2598 /* Ensure current function's preferred stack boundary is at least
2599 what we need. We don't have to increase alignment for recursive
2601 if (cfun
->preferred_stack_boundary
< preferred_stack_boundary
2602 && fndecl
!= current_function_decl
)
2603 cfun
->preferred_stack_boundary
= preferred_stack_boundary
;
2605 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2607 function_call_count
++;
2609 /* We want to make two insn chains; one for a sibling call, the other
2610 for a normal call. We will select one of the two chains after
2611 initial RTL generation is complete. */
2612 for (pass
= 0; pass
< 2; pass
++)
2614 int sibcall_failure
= 0;
2615 /* We want to emit ay pending stack adjustments before the tail
2616 recursion "call". That way we know any adjustment after the tail
2617 recursion call can be ignored if we indeed use the tail recursion
2619 int save_pending_stack_adjust
= 0;
2620 int save_stack_pointer_delta
= 0;
2622 rtx before_call
, next_arg_reg
;
2626 if (! try_tail_call
)
2629 /* Emit any queued insns now; otherwise they would end up in
2630 only one of the alternates. */
2633 /* State variables we need to save and restore between
2635 save_pending_stack_adjust
= pending_stack_adjust
;
2636 save_stack_pointer_delta
= stack_pointer_delta
;
2639 flags
&= ~ECF_SIBCALL
;
2641 flags
|= ECF_SIBCALL
;
2643 /* Other state variables that we must reinitialize each time
2644 through the loop (that are not initialized by the loop itself). */
2648 /* Start a new sequence for the normal call case.
2650 From this point on, if the sibling call fails, we want to set
2651 sibcall_failure instead of continuing the loop. */
2656 /* We know at this point that there are not currently any
2657 pending cleanups. If, however, in the process of evaluating
2658 the arguments we were to create some, we'll need to be
2659 able to get rid of them. */
2660 expand_start_target_temps ();
2663 /* Don't let pending stack adjusts add up to too much.
2664 Also, do all pending adjustments now if there is any chance
2665 this might be a call to alloca or if we are expanding a sibling
2667 if (pending_stack_adjust
>= 32
2668 || (pending_stack_adjust
> 0 && (flags
& ECF_MAY_BE_ALLOCA
))
2670 do_pending_stack_adjust ();
2672 /* When calling a const function, we must pop the stack args right away,
2673 so that the pop is deleted or moved with the call. */
2674 if (flags
& (ECF_CONST
| ECF_PURE
))
2677 /* Push the temporary stack slot level so that we can free any
2678 temporaries we make. */
2681 #ifdef FINAL_REG_PARM_STACK_SPACE
2682 reg_parm_stack_space
= FINAL_REG_PARM_STACK_SPACE (args_size
.constant
,
2685 /* Precompute any arguments as needed. */
2687 precompute_arguments (flags
, num_actuals
, args
);
2689 /* Now we are about to start emitting insns that can be deleted
2690 if a libcall is deleted. */
2691 if (flags
& (ECF_CONST
| ECF_PURE
| ECF_MALLOC
))
2694 adjusted_args_size
= args_size
;
2695 /* Compute the actual size of the argument block required. The variable
2696 and constant sizes must be combined, the size may have to be rounded,
2697 and there may be a minimum required size. When generating a sibcall
2698 pattern, do not round up, since we'll be re-using whatever space our
2700 unadjusted_args_size
2701 = compute_argument_block_size (reg_parm_stack_space
,
2702 &adjusted_args_size
,
2704 : preferred_stack_boundary
));
2706 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2708 /* The argument block when performing a sibling call is the
2709 incoming argument block. */
2712 argblock
= virtual_incoming_args_rtx
;
2713 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2714 sbitmap_zero (stored_args_map
);
2717 /* If we have no actual push instructions, or shouldn't use them,
2718 make space for all args right now. */
2719 else if (adjusted_args_size
.var
!= 0)
2721 if (old_stack_level
== 0)
2723 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
2724 old_pending_adj
= pending_stack_adjust
;
2725 pending_stack_adjust
= 0;
2726 /* stack_arg_under_construction says whether a stack arg is
2727 being constructed at the old stack level. Pushing the stack
2728 gets a clean outgoing argument block. */
2729 old_stack_arg_under_construction
= stack_arg_under_construction
;
2730 stack_arg_under_construction
= 0;
2732 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2736 /* Note that we must go through the motions of allocating an argument
2737 block even if the size is zero because we may be storing args
2738 in the area reserved for register arguments, which may be part of
2741 int needed
= adjusted_args_size
.constant
;
2743 /* Store the maximum argument space used. It will be pushed by
2744 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2747 if (needed
> current_function_outgoing_args_size
)
2748 current_function_outgoing_args_size
= needed
;
2750 if (must_preallocate
)
2752 if (ACCUMULATE_OUTGOING_ARGS
)
2754 /* Since the stack pointer will never be pushed, it is
2755 possible for the evaluation of a parm to clobber
2756 something we have already written to the stack.
2757 Since most function calls on RISC machines do not use
2758 the stack, this is uncommon, but must work correctly.
2760 Therefore, we save any area of the stack that was already
2761 written and that we are using. Here we set up to do this
2762 by making a new stack usage map from the old one. The
2763 actual save will be done by store_one_arg.
2765 Another approach might be to try to reorder the argument
2766 evaluations to avoid this conflicting stack usage. */
2768 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2769 /* Since we will be writing into the entire argument area,
2770 the map must be allocated for its entire size, not just
2771 the part that is the responsibility of the caller. */
2772 needed
+= reg_parm_stack_space
;
2775 #ifdef ARGS_GROW_DOWNWARD
2776 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2779 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2783 = (char *) alloca (highest_outgoing_arg_in_use
);
2785 if (initial_highest_arg_in_use
)
2786 memcpy (stack_usage_map
, initial_stack_usage_map
,
2787 initial_highest_arg_in_use
);
2789 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2790 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2791 (highest_outgoing_arg_in_use
2792 - initial_highest_arg_in_use
));
2795 /* The address of the outgoing argument list must not be
2796 copied to a register here, because argblock would be left
2797 pointing to the wrong place after the call to
2798 allocate_dynamic_stack_space below. */
2800 argblock
= virtual_outgoing_args_rtx
;
2804 if (inhibit_defer_pop
== 0)
2806 /* Try to reuse some or all of the pending_stack_adjust
2807 to get this space. */
2809 = (combine_pending_stack_adjustment_and_call
2810 (unadjusted_args_size
,
2811 &adjusted_args_size
,
2812 preferred_unit_stack_boundary
));
2814 /* combine_pending_stack_adjustment_and_call computes
2815 an adjustment before the arguments are allocated.
2816 Account for them and see whether or not the stack
2817 needs to go up or down. */
2818 needed
= unadjusted_args_size
- needed
;
2822 /* We're releasing stack space. */
2823 /* ??? We can avoid any adjustment at all if we're
2824 already aligned. FIXME. */
2825 pending_stack_adjust
= -needed
;
2826 do_pending_stack_adjust ();
2830 /* We need to allocate space. We'll do that in
2831 push_block below. */
2832 pending_stack_adjust
= 0;
2835 /* Special case this because overhead of `push_block' in
2836 this case is non-trivial. */
2838 argblock
= virtual_outgoing_args_rtx
;
2840 argblock
= push_block (GEN_INT (needed
), 0, 0);
2842 /* We only really need to call `copy_to_reg' in the case
2843 where push insns are going to be used to pass ARGBLOCK
2844 to a function call in ARGS. In that case, the stack
2845 pointer changes value from the allocation point to the
2846 call point, and hence the value of
2847 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2848 as well always do it. */
2849 argblock
= copy_to_reg (argblock
);
2851 /* The save/restore code in store_one_arg handles all
2852 cases except one: a constructor call (including a C
2853 function returning a BLKmode struct) to initialize
2855 if (stack_arg_under_construction
)
2857 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2858 rtx push_size
= GEN_INT (reg_parm_stack_space
2859 + adjusted_args_size
.constant
);
2861 rtx push_size
= GEN_INT (adjusted_args_size
.constant
);
2863 if (old_stack_level
== 0)
2865 emit_stack_save (SAVE_BLOCK
, &old_stack_level
,
2867 old_pending_adj
= pending_stack_adjust
;
2868 pending_stack_adjust
= 0;
2869 /* stack_arg_under_construction says whether a stack
2870 arg is being constructed at the old stack level.
2871 Pushing the stack gets a clean outgoing argument
2873 old_stack_arg_under_construction
2874 = stack_arg_under_construction
;
2875 stack_arg_under_construction
= 0;
2876 /* Make a new map for the new argument list. */
2877 stack_usage_map
= (char *)
2878 alloca (highest_outgoing_arg_in_use
);
2879 memset (stack_usage_map
, 0, highest_outgoing_arg_in_use
);
2880 highest_outgoing_arg_in_use
= 0;
2882 allocate_dynamic_stack_space (push_size
, NULL_RTX
,
2885 /* If argument evaluation might modify the stack pointer,
2886 copy the address of the argument list to a register. */
2887 for (i
= 0; i
< num_actuals
; i
++)
2888 if (args
[i
].pass_on_stack
)
2890 argblock
= copy_addr_to_reg (argblock
);
2897 compute_argument_addresses (args
, argblock
, num_actuals
);
2899 /* If we push args individually in reverse order, perform stack alignment
2900 before the first push (the last arg). */
2901 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2902 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2904 /* When the stack adjustment is pending, we get better code
2905 by combining the adjustments. */
2906 if (pending_stack_adjust
2907 && ! (flags
& (ECF_CONST
| ECF_PURE
))
2908 && ! inhibit_defer_pop
)
2910 pending_stack_adjust
2911 = (combine_pending_stack_adjustment_and_call
2912 (unadjusted_args_size
,
2913 &adjusted_args_size
,
2914 preferred_unit_stack_boundary
));
2915 do_pending_stack_adjust ();
2917 else if (argblock
== 0)
2918 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2919 - unadjusted_args_size
));
2921 /* Now that the stack is properly aligned, pops can't safely
2922 be deferred during the evaluation of the arguments. */
2925 funexp
= rtx_for_function_call (fndecl
, exp
);
2927 /* Figure out the register where the value, if any, will come back. */
2929 if (TYPE_MODE (TREE_TYPE (exp
)) != VOIDmode
2930 && ! structure_value_addr
)
2932 if (pcc_struct_value
)
2933 valreg
= hard_function_value (build_pointer_type (TREE_TYPE (exp
)),
2934 fndecl
, (pass
== 0));
2936 valreg
= hard_function_value (TREE_TYPE (exp
), fndecl
, (pass
== 0));
2939 /* Precompute all register parameters. It isn't safe to compute anything
2940 once we have started filling any specific hard regs. */
2941 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2943 #ifdef REG_PARM_STACK_SPACE
2944 /* Save the fixed argument area if it's part of the caller's frame and
2945 is clobbered by argument setup for this call. */
2946 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2947 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2948 &low_to_save
, &high_to_save
);
2951 /* Now store (and compute if necessary) all non-register parms.
2952 These come before register parms, since they can require block-moves,
2953 which could clobber the registers used for register parms.
2954 Parms which have partial registers are not stored here,
2955 but we do preallocate space here if they want that. */
2957 for (i
= 0; i
< num_actuals
; i
++)
2958 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2960 rtx before_arg
= get_last_insn ();
2962 if (store_one_arg (&args
[i
], argblock
, flags
,
2963 adjusted_args_size
.var
!= 0,
2964 reg_parm_stack_space
)
2966 && check_sibcall_argument_overlap (before_arg
,
2968 sibcall_failure
= 1;
2971 /* If we have a parm that is passed in registers but not in memory
2972 and whose alignment does not permit a direct copy into registers,
2973 make a group of pseudos that correspond to each register that we
2975 if (STRICT_ALIGNMENT
)
2976 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2978 /* Now store any partially-in-registers parm.
2979 This is the last place a block-move can happen. */
2981 for (i
= 0; i
< num_actuals
; i
++)
2982 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2984 rtx before_arg
= get_last_insn ();
2986 if (store_one_arg (&args
[i
], argblock
, flags
,
2987 adjusted_args_size
.var
!= 0,
2988 reg_parm_stack_space
)
2990 && check_sibcall_argument_overlap (before_arg
,
2992 sibcall_failure
= 1;
2995 /* If we pushed args in forward order, perform stack alignment
2996 after pushing the last arg. */
2997 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
2998 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2999 - unadjusted_args_size
));
3001 /* If register arguments require space on the stack and stack space
3002 was not preallocated, allocate stack space here for arguments
3003 passed in registers. */
3004 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3005 if (!ACCUMULATE_OUTGOING_ARGS
3006 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
3007 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
3010 /* Pass the function the address in which to return a
3012 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
3014 emit_move_insn (struct_value_rtx
,
3016 force_operand (structure_value_addr
,
3019 /* Mark the memory for the aggregate as write-only. */
3020 if (current_function_check_memory_usage
)
3021 emit_library_call (chkr_set_right_libfunc
, LCT_CONST_MAKE_BLOCK
,
3023 structure_value_addr
, ptr_mode
,
3024 GEN_INT (struct_value_size
),
3025 TYPE_MODE (sizetype
),
3026 GEN_INT (MEMORY_USE_WO
),
3027 TYPE_MODE (integer_type_node
));
3029 if (GET_CODE (struct_value_rtx
) == REG
)
3030 use_reg (&call_fusage
, struct_value_rtx
);
3033 funexp
= prepare_call_address (funexp
, fndecl
, &call_fusage
,
3034 reg_parm_seen
, pass
== 0);
3036 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
);
3038 /* Perform postincrements before actually calling the function. */
3041 /* Save a pointer to the last insn before the call, so that we can
3042 later safely search backwards to find the CALL_INSN. */
3043 before_call
= get_last_insn ();
3045 /* Set up next argument register. For sibling calls on machines
3046 with register windows this should be the incoming register. */
3047 #ifdef FUNCTION_INCOMING_ARG
3049 next_arg_reg
= FUNCTION_INCOMING_ARG (args_so_far
, VOIDmode
,
3053 next_arg_reg
= FUNCTION_ARG (args_so_far
, VOIDmode
,
3056 /* All arguments and registers used for the call must be set up by
3059 /* Stack must be properly aligned now. */
3060 if (pass
&& stack_pointer_delta
% preferred_unit_stack_boundary
)
3063 /* Generate the actual call instruction. */
3064 emit_call_1 (funexp
, fndecl
, funtype
, unadjusted_args_size
,
3065 adjusted_args_size
.constant
, struct_value_size
,
3066 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
3069 /* Verify that we've deallocated all the stack we used. */
3071 && old_stack_allocated
!= stack_pointer_delta
- pending_stack_adjust
)
3074 /* If call is cse'able, make appropriate pair of reg-notes around it.
3075 Test valreg so we don't crash; may safely ignore `const'
3076 if return type is void. Disable for PARALLEL return values, because
3077 we have no way to move such values into a pseudo register. */
3079 && (flags
& (ECF_CONST
| ECF_PURE
))
3080 && valreg
!= 0 && GET_CODE (valreg
) != PARALLEL
)
3083 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
3086 /* Mark the return value as a pointer if needed. */
3087 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
3088 mark_reg_pointer (temp
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp
))));
3090 /* Construct an "equal form" for the value which mentions all the
3091 arguments in order as well as the function name. */
3092 for (i
= 0; i
< num_actuals
; i
++)
3093 note
= gen_rtx_EXPR_LIST (VOIDmode
, args
[i
].initial_value
, note
);
3094 note
= gen_rtx_EXPR_LIST (VOIDmode
, funexp
, note
);
3096 insns
= get_insns ();
3099 if (flags
& ECF_PURE
)
3100 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3101 gen_rtx_USE (VOIDmode
,
3102 gen_rtx_MEM (BLKmode
,
3103 gen_rtx_SCRATCH (VOIDmode
))), note
);
3105 emit_libcall_block (insns
, temp
, valreg
, note
);
3109 else if (flags
& (ECF_CONST
| ECF_PURE
))
3111 /* Otherwise, just write out the sequence without a note. */
3112 rtx insns
= get_insns ();
3117 else if (flags
& ECF_MALLOC
)
3119 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
3122 /* The return value from a malloc-like function is a pointer. */
3123 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
3124 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
3126 emit_move_insn (temp
, valreg
);
3128 /* The return value from a malloc-like function can not alias
3130 last
= get_last_insn ();
3132 gen_rtx_EXPR_LIST (REG_NOALIAS
, temp
, REG_NOTES (last
));
3134 /* Write out the sequence. */
3135 insns
= get_insns ();
3141 /* For calls to `setjmp', etc., inform flow.c it should complain
3142 if nonvolatile values are live. For functions that cannot return,
3143 inform flow that control does not fall through. */
3145 if ((flags
& (ECF_NORETURN
| ECF_LONGJMP
)) || pass
== 0)
3147 /* The barrier must be emitted
3148 immediately after the CALL_INSN. Some ports emit more
3149 than just a CALL_INSN above, so we must search for it here. */
3151 rtx last
= get_last_insn ();
3152 while (GET_CODE (last
) != CALL_INSN
)
3154 last
= PREV_INSN (last
);
3155 /* There was no CALL_INSN? */
3156 if (last
== before_call
)
3160 emit_barrier_after (last
);
3163 if (flags
& ECF_LONGJMP
)
3164 current_function_calls_longjmp
= 1;
3166 /* If this function is returning into a memory location marked as
3167 readonly, it means it is initializing that location. But we normally
3168 treat functions as not clobbering such locations, so we need to
3169 specify that this one does. */
3170 if (target
!= 0 && GET_CODE (target
) == MEM
3171 && structure_value_addr
!= 0 && RTX_UNCHANGING_P (target
))
3172 emit_insn (gen_rtx_CLOBBER (VOIDmode
, target
));
3174 /* If value type not void, return an rtx for the value. */
3176 /* If there are cleanups to be called, don't use a hard reg as target.
3177 We need to double check this and see if it matters anymore. */
3178 if (any_pending_cleanups (1))
3180 if (target
&& REG_P (target
)
3181 && REGNO (target
) < FIRST_PSEUDO_REGISTER
)
3183 sibcall_failure
= 1;
3186 if (TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
3189 target
= const0_rtx
;
3191 else if (structure_value_addr
)
3193 if (target
== 0 || GET_CODE (target
) != MEM
)
3196 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
3197 memory_address (TYPE_MODE (TREE_TYPE (exp
)),
3198 structure_value_addr
));
3199 set_mem_attributes (target
, exp
, 1);
3202 else if (pcc_struct_value
)
3204 /* This is the special C++ case where we need to
3205 know what the true target was. We take care to
3206 never use this value more than once in one expression. */
3207 target
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
3208 copy_to_reg (valreg
));
3209 set_mem_attributes (target
, exp
, 1);
3211 /* Handle calls that return values in multiple non-contiguous locations.
3212 The Irix 6 ABI has examples of this. */
3213 else if (GET_CODE (valreg
) == PARALLEL
)
3217 /* This will only be assigned once, so it can be readonly. */
3218 tree nt
= build_qualified_type (TREE_TYPE (exp
),
3219 (TYPE_QUALS (TREE_TYPE (exp
))
3220 | TYPE_QUAL_CONST
));
3222 target
= assign_temp (nt
, 0, 1, 1);
3223 preserve_temp_slots (target
);
3226 if (! rtx_equal_p (target
, valreg
))
3227 emit_group_store (target
, valreg
,
3228 int_size_in_bytes (TREE_TYPE (exp
)),
3229 TYPE_ALIGN (TREE_TYPE (exp
)));
3231 /* We can not support sibling calls for this case. */
3232 sibcall_failure
= 1;
3235 && GET_MODE (target
) == TYPE_MODE (TREE_TYPE (exp
))
3236 && GET_MODE (target
) == GET_MODE (valreg
))
3238 /* TARGET and VALREG cannot be equal at this point because the
3239 latter would not have REG_FUNCTION_VALUE_P true, while the
3240 former would if it were referring to the same register.
3242 If they refer to the same register, this move will be a no-op,
3243 except when function inlining is being done. */
3244 emit_move_insn (target
, valreg
);
3246 else if (TYPE_MODE (TREE_TYPE (exp
)) == BLKmode
)
3248 target
= copy_blkmode_from_reg (target
, valreg
, TREE_TYPE (exp
));
3250 /* We can not support sibling calls for this case. */
3251 sibcall_failure
= 1;
3254 target
= copy_to_reg (valreg
);
3256 #ifdef PROMOTE_FUNCTION_RETURN
3257 /* If we promoted this return value, make the proper SUBREG. TARGET
3258 might be const0_rtx here, so be careful. */
3259 if (GET_CODE (target
) == REG
3260 && TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
3261 && GET_MODE (target
) != TYPE_MODE (TREE_TYPE (exp
)))
3263 tree type
= TREE_TYPE (exp
);
3264 int unsignedp
= TREE_UNSIGNED (type
);
3267 /* If we don't promote as expected, something is wrong. */
3268 if (GET_MODE (target
)
3269 != promote_mode (type
, TYPE_MODE (type
), &unsignedp
, 1))
3272 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
3273 && GET_MODE_SIZE (GET_MODE (target
))
3274 > GET_MODE_SIZE (TYPE_MODE (type
)))
3276 offset
= GET_MODE_SIZE (GET_MODE (target
))
3277 - GET_MODE_SIZE (TYPE_MODE (type
));
3278 if (! BYTES_BIG_ENDIAN
)
3279 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
3280 else if (! WORDS_BIG_ENDIAN
)
3281 offset
%= UNITS_PER_WORD
;
3283 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
3284 SUBREG_PROMOTED_VAR_P (target
) = 1;
3285 SUBREG_PROMOTED_UNSIGNED_P (target
) = unsignedp
;
3289 /* If size of args is variable or this was a constructor call for a stack
3290 argument, restore saved stack-pointer value. */
3292 if (old_stack_level
&& ! (flags
& ECF_SP_DEPRESSED
))
3294 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
3295 pending_stack_adjust
= old_pending_adj
;
3296 stack_arg_under_construction
= old_stack_arg_under_construction
;
3297 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3298 stack_usage_map
= initial_stack_usage_map
;
3299 sibcall_failure
= 1;
3301 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
3303 #ifdef REG_PARM_STACK_SPACE
3306 restore_fixed_argument_area (save_area
, argblock
,
3307 high_to_save
, low_to_save
);
3311 /* If we saved any argument areas, restore them. */
3312 for (i
= 0; i
< num_actuals
; i
++)
3313 if (args
[i
].save_area
)
3315 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
3317 = gen_rtx_MEM (save_mode
,
3318 memory_address (save_mode
,
3319 XEXP (args
[i
].stack_slot
, 0)));
3321 if (save_mode
!= BLKmode
)
3322 emit_move_insn (stack_area
, args
[i
].save_area
);
3324 emit_block_move (stack_area
,
3325 validize_mem (args
[i
].save_area
),
3326 GEN_INT (args
[i
].size
.constant
));
3329 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3330 stack_usage_map
= initial_stack_usage_map
;
3333 /* If this was alloca, record the new stack level for nonlocal gotos.
3334 Check for the handler slots since we might not have a save area
3335 for non-local gotos. */
3337 if ((flags
& ECF_MAY_BE_ALLOCA
) && nonlocal_goto_handler_slots
!= 0)
3338 emit_stack_save (SAVE_NONLOCAL
, &nonlocal_goto_stack_level
, NULL_RTX
);
3342 /* Free up storage we no longer need. */
3343 for (i
= 0; i
< num_actuals
; ++i
)
3344 if (args
[i
].aligned_regs
)
3345 free (args
[i
].aligned_regs
);
3349 /* Undo the fake expand_start_target_temps we did earlier. If
3350 there had been any cleanups created, we've already set
3352 expand_end_target_temps ();
3355 insns
= get_insns ();
3360 tail_call_insns
= insns
;
3362 /* Restore the pending stack adjustment now that we have
3363 finished generating the sibling call sequence. */
3365 pending_stack_adjust
= save_pending_stack_adjust
;
3366 stack_pointer_delta
= save_stack_pointer_delta
;
3368 /* Prepare arg structure for next iteration. */
3369 for (i
= 0; i
< num_actuals
; i
++)
3372 args
[i
].aligned_regs
= 0;
3376 sbitmap_free (stored_args_map
);
3379 normal_call_insns
= insns
;
3381 /* If something prevents making this a sibling call,
3382 zero out the sequence. */
3383 if (sibcall_failure
)
3384 tail_call_insns
= NULL_RTX
;
3387 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3388 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3389 can happen if the arguments to this function call an inline
3390 function who's expansion contains another CALL_PLACEHOLDER.
3392 If there are any C_Ps in any of these sequences, replace them
3393 with their normal call. */
3395 for (insn
= normal_call_insns
; insn
; insn
= NEXT_INSN (insn
))
3396 if (GET_CODE (insn
) == CALL_INSN
3397 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3398 replace_call_placeholder (insn
, sibcall_use_normal
);
3400 for (insn
= tail_call_insns
; insn
; insn
= NEXT_INSN (insn
))
3401 if (GET_CODE (insn
) == CALL_INSN
3402 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3403 replace_call_placeholder (insn
, sibcall_use_normal
);
3405 for (insn
= tail_recursion_insns
; insn
; insn
= NEXT_INSN (insn
))
3406 if (GET_CODE (insn
) == CALL_INSN
3407 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
3408 replace_call_placeholder (insn
, sibcall_use_normal
);
3410 /* If this was a potential tail recursion site, then emit a
3411 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3412 One of them will be selected later. */
3413 if (tail_recursion_insns
|| tail_call_insns
)
3415 /* The tail recursion label must be kept around. We could expose
3416 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3417 and makes determining true tail recursion sites difficult.
3419 So we set LABEL_PRESERVE_P here, then clear it when we select
3420 one of the call sequences after rtl generation is complete. */
3421 if (tail_recursion_insns
)
3422 LABEL_PRESERVE_P (tail_recursion_label
) = 1;
3423 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode
, normal_call_insns
,
3425 tail_recursion_insns
,
3426 tail_recursion_label
));
3429 emit_insns (normal_call_insns
);
3431 currently_expanding_call
--;
3433 /* If this function returns with the stack pointer depressed, ensure
3434 this block saves and restores the stack pointer, show it was
3435 changed, and adjust for any outgoing arg space. */
3436 if (flags
& ECF_SP_DEPRESSED
)
3438 clear_pending_stack_adjust ();
3439 emit_insn (gen_rtx (CLOBBER
, VOIDmode
, stack_pointer_rtx
));
3440 emit_move_insn (virtual_stack_dynamic_rtx
, stack_pointer_rtx
);
3441 save_stack_pointer ();
3447 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3448 The RETVAL parameter specifies whether return value needs to be saved, other
3449 parameters are documented in the emit_library_call function below. */
3452 emit_library_call_value_1 (retval
, orgfun
, value
, fn_type
, outmode
, nargs
, p
)
3456 enum libcall_type fn_type
;
3457 enum machine_mode outmode
;
3461 /* Total size in bytes of all the stack-parms scanned so far. */
3462 struct args_size args_size
;
3463 /* Size of arguments before any adjustments (such as rounding). */
3464 struct args_size original_args_size
;
3469 struct args_size alignment_pad
;
3471 CUMULATIVE_ARGS args_so_far
;
3475 enum machine_mode mode
;
3478 struct args_size offset
;
3479 struct args_size size
;
3483 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3484 rtx call_fusage
= 0;
3487 int pcc_struct_value
= 0;
3488 int struct_value_size
= 0;
3490 int reg_parm_stack_space
= 0;
3494 #ifdef REG_PARM_STACK_SPACE
3495 /* Define the boundary of the register parm stack space that needs to be
3497 int low_to_save
= -1, high_to_save
= 0;
3498 rtx save_area
= 0; /* Place that it is saved. */
3501 /* Size of the stack reserved for parameter registers. */
3502 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3503 char *initial_stack_usage_map
= stack_usage_map
;
3505 #ifdef REG_PARM_STACK_SPACE
3506 #ifdef MAYBE_REG_PARM_STACK_SPACE
3507 reg_parm_stack_space
= MAYBE_REG_PARM_STACK_SPACE
;
3509 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3513 /* By default, library functions can not throw. */
3514 flags
= ECF_NOTHROW
;
3521 /* Nothing to do here. */
3523 case LCT_CONST_MAKE_BLOCK
:
3526 case LCT_PURE_MAKE_BLOCK
:
3530 flags
|= ECF_NORETURN
;
3533 flags
= ECF_NORETURN
;
3535 case LCT_ALWAYS_RETURN
:
3536 flags
= ECF_ALWAYS_RETURN
;
3538 case LCT_RETURNS_TWICE
:
3539 flags
= ECF_RETURNS_TWICE
;
3544 /* Ensure current function's preferred stack boundary is at least
3546 if (cfun
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3547 cfun
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3549 /* If this kind of value comes back in memory,
3550 decide where in memory it should come back. */
3551 if (outmode
!= VOIDmode
&& aggregate_value_p (type_for_mode (outmode
, 0)))
3553 #ifdef PCC_STATIC_STRUCT_RETURN
3555 = hard_function_value (build_pointer_type (type_for_mode (outmode
, 0)),
3557 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3558 pcc_struct_value
= 1;
3560 value
= gen_reg_rtx (outmode
);
3561 #else /* not PCC_STATIC_STRUCT_RETURN */
3562 struct_value_size
= GET_MODE_SIZE (outmode
);
3563 if (value
!= 0 && GET_CODE (value
) == MEM
)
3566 mem_value
= assign_temp (type_for_mode (outmode
, 0), 0, 1, 1);
3569 /* This call returns a big structure. */
3570 flags
&= ~(ECF_CONST
| ECF_PURE
);
3573 /* ??? Unfinished: must pass the memory address as an argument. */
3575 /* Copy all the libcall-arguments out of the varargs data
3576 and into a vector ARGVEC.
3578 Compute how to pass each argument. We only support a very small subset
3579 of the full argument passing conventions to limit complexity here since
3580 library functions shouldn't have many args. */
3582 argvec
= (struct arg
*) alloca ((nargs
+ 1) * sizeof (struct arg
));
3583 memset ((char *) argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3585 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3586 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3588 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0);
3591 args_size
.constant
= 0;
3596 /* Now we are about to start emitting insns that can be deleted
3597 if a libcall is deleted. */
3598 if (flags
& (ECF_CONST
| ECF_PURE
))
3603 /* If there's a structure value address to be passed,
3604 either pass it in the special place, or pass it as an extra argument. */
3605 if (mem_value
&& struct_value_rtx
== 0 && ! pcc_struct_value
)
3607 rtx addr
= XEXP (mem_value
, 0);
3610 /* Make sure it is a reasonable operand for a move or push insn. */
3611 if (GET_CODE (addr
) != REG
&& GET_CODE (addr
) != MEM
3612 && ! (CONSTANT_P (addr
) && LEGITIMATE_CONSTANT_P (addr
)))
3613 addr
= force_operand (addr
, NULL_RTX
);
3615 argvec
[count
].value
= addr
;
3616 argvec
[count
].mode
= Pmode
;
3617 argvec
[count
].partial
= 0;
3619 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, Pmode
, NULL_TREE
, 1);
3620 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3621 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, Pmode
, NULL_TREE
, 1))
3625 locate_and_pad_parm (Pmode
, NULL_TREE
,
3626 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3629 argvec
[count
].reg
!= 0,
3631 NULL_TREE
, &args_size
, &argvec
[count
].offset
,
3632 &argvec
[count
].size
, &alignment_pad
);
3634 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3635 || reg_parm_stack_space
> 0)
3636 args_size
.constant
+= argvec
[count
].size
.constant
;
3638 FUNCTION_ARG_ADVANCE (args_so_far
, Pmode
, (tree
) 0, 1);
3643 for (; count
< nargs
; count
++)
3645 rtx val
= va_arg (p
, rtx
);
3646 enum machine_mode mode
= va_arg (p
, enum machine_mode
);
3648 /* We cannot convert the arg value to the mode the library wants here;
3649 must do it earlier where we know the signedness of the arg. */
3651 || (GET_MODE (val
) != mode
&& GET_MODE (val
) != VOIDmode
))
3654 /* On some machines, there's no way to pass a float to a library fcn.
3655 Pass it as a double instead. */
3656 #ifdef LIBGCC_NEEDS_DOUBLE
3657 if (LIBGCC_NEEDS_DOUBLE
&& mode
== SFmode
)
3658 val
= convert_modes (DFmode
, SFmode
, val
, 0), mode
= DFmode
;
3661 /* There's no need to call protect_from_queue, because
3662 either emit_move_insn or emit_push_insn will do that. */
3664 /* Make sure it is a reasonable operand for a move or push insn. */
3665 if (GET_CODE (val
) != REG
&& GET_CODE (val
) != MEM
3666 && ! (CONSTANT_P (val
) && LEGITIMATE_CONSTANT_P (val
)))
3667 val
= force_operand (val
, NULL_RTX
);
3669 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3670 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far
, mode
, NULL_TREE
, 1))
3674 #ifdef FUNCTION_ARG_CALLEE_COPIES
3675 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far
, mode
,
3680 if (GET_MODE (val
) == MEM
&& ! must_copy
)
3684 slot
= assign_temp (type_for_mode (mode
, 0), 0, 1, 1);
3685 emit_move_insn (slot
, val
);
3689 tree type
= type_for_mode (mode
, 0);
3691 slot
= gen_rtx_MEM (mode
,
3692 expand_expr (build1 (ADDR_EXPR
,
3695 make_tree (type
, val
)),
3696 NULL_RTX
, VOIDmode
, 0));
3699 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3700 gen_rtx_USE (VOIDmode
, slot
),
3703 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3704 gen_rtx_CLOBBER (VOIDmode
,
3709 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3713 argvec
[count
].value
= val
;
3714 argvec
[count
].mode
= mode
;
3716 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, mode
, NULL_TREE
, 1);
3718 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3719 argvec
[count
].partial
3720 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, mode
, NULL_TREE
, 1);
3722 argvec
[count
].partial
= 0;
3725 locate_and_pad_parm (mode
, NULL_TREE
,
3726 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3729 argvec
[count
].reg
!= 0,
3731 NULL_TREE
, &args_size
, &argvec
[count
].offset
,
3732 &argvec
[count
].size
, &alignment_pad
);
3734 if (argvec
[count
].size
.var
)
3737 if (reg_parm_stack_space
== 0 && argvec
[count
].partial
)
3738 argvec
[count
].size
.constant
-= argvec
[count
].partial
* UNITS_PER_WORD
;
3740 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3741 || reg_parm_stack_space
> 0)
3742 args_size
.constant
+= argvec
[count
].size
.constant
;
3744 FUNCTION_ARG_ADVANCE (args_so_far
, mode
, (tree
) 0, 1);
3747 #ifdef FINAL_REG_PARM_STACK_SPACE
3748 reg_parm_stack_space
= FINAL_REG_PARM_STACK_SPACE (args_size
.constant
,
3751 /* If this machine requires an external definition for library
3752 functions, write one out. */
3753 assemble_external_libcall (fun
);
3755 original_args_size
= args_size
;
3756 args_size
.constant
= (((args_size
.constant
3757 + stack_pointer_delta
3761 - stack_pointer_delta
);
3763 args_size
.constant
= MAX (args_size
.constant
,
3764 reg_parm_stack_space
);
3766 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3767 args_size
.constant
-= reg_parm_stack_space
;
3770 if (args_size
.constant
> current_function_outgoing_args_size
)
3771 current_function_outgoing_args_size
= args_size
.constant
;
3773 if (ACCUMULATE_OUTGOING_ARGS
)
3775 /* Since the stack pointer will never be pushed, it is possible for
3776 the evaluation of a parm to clobber something we have already
3777 written to the stack. Since most function calls on RISC machines
3778 do not use the stack, this is uncommon, but must work correctly.
3780 Therefore, we save any area of the stack that was already written
3781 and that we are using. Here we set up to do this by making a new
3782 stack usage map from the old one.
3784 Another approach might be to try to reorder the argument
3785 evaluations to avoid this conflicting stack usage. */
3787 needed
= args_size
.constant
;
3789 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3790 /* Since we will be writing into the entire argument area, the
3791 map must be allocated for its entire size, not just the part that
3792 is the responsibility of the caller. */
3793 needed
+= reg_parm_stack_space
;
3796 #ifdef ARGS_GROW_DOWNWARD
3797 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3800 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3803 stack_usage_map
= (char *) alloca (highest_outgoing_arg_in_use
);
3805 if (initial_highest_arg_in_use
)
3806 memcpy (stack_usage_map
, initial_stack_usage_map
,
3807 initial_highest_arg_in_use
);
3809 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3810 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3811 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3814 /* We must be careful to use virtual regs before they're instantiated,
3815 and real regs afterwards. Loop optimization, for example, can create
3816 new libcalls after we've instantiated the virtual regs, and if we
3817 use virtuals anyway, they won't match the rtl patterns. */
3819 if (virtuals_instantiated
)
3820 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3822 argblock
= virtual_outgoing_args_rtx
;
3827 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3830 /* If we push args individually in reverse order, perform stack alignment
3831 before the first push (the last arg). */
3832 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3833 anti_adjust_stack (GEN_INT (args_size
.constant
3834 - original_args_size
.constant
));
3836 if (PUSH_ARGS_REVERSED
)
3847 #ifdef REG_PARM_STACK_SPACE
3848 if (ACCUMULATE_OUTGOING_ARGS
)
3850 /* The argument list is the property of the called routine and it
3851 may clobber it. If the fixed area has been used for previous
3852 parameters, we must save and restore it.
3854 Here we compute the boundary of the that needs to be saved, if any. */
3856 #ifdef ARGS_GROW_DOWNWARD
3857 for (count
= 0; count
< reg_parm_stack_space
+ 1; count
++)
3859 for (count
= 0; count
< reg_parm_stack_space
; count
++)
3862 if (count
>= highest_outgoing_arg_in_use
3863 || stack_usage_map
[count
] == 0)
3866 if (low_to_save
== -1)
3867 low_to_save
= count
;
3869 high_to_save
= count
;
3872 if (low_to_save
>= 0)
3874 int num_to_save
= high_to_save
- low_to_save
+ 1;
3875 enum machine_mode save_mode
3876 = mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
3879 /* If we don't have the required alignment, must do this in BLKmode. */
3880 if ((low_to_save
& (MIN (GET_MODE_SIZE (save_mode
),
3881 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
3882 save_mode
= BLKmode
;
3884 #ifdef ARGS_GROW_DOWNWARD
3885 stack_area
= gen_rtx_MEM (save_mode
,
3886 memory_address (save_mode
,
3887 plus_constant (argblock
,
3890 stack_area
= gen_rtx_MEM (save_mode
,
3891 memory_address (save_mode
,
3892 plus_constant (argblock
,
3895 if (save_mode
== BLKmode
)
3897 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
3898 set_mem_align (save_area
, PARM_BOUNDARY
);
3899 emit_block_move (validize_mem (save_area
), stack_area
,
3900 GEN_INT (num_to_save
));
3904 save_area
= gen_reg_rtx (save_mode
);
3905 emit_move_insn (save_area
, stack_area
);
3911 /* Push the args that need to be pushed. */
3913 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3914 are to be pushed. */
3915 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3917 enum machine_mode mode
= argvec
[argnum
].mode
;
3918 rtx val
= argvec
[argnum
].value
;
3919 rtx reg
= argvec
[argnum
].reg
;
3920 int partial
= argvec
[argnum
].partial
;
3921 int lower_bound
= 0, upper_bound
= 0, i
;
3923 if (! (reg
!= 0 && partial
== 0))
3925 if (ACCUMULATE_OUTGOING_ARGS
)
3927 /* If this is being stored into a pre-allocated, fixed-size,
3928 stack area, save any previous data at that location. */
3930 #ifdef ARGS_GROW_DOWNWARD
3931 /* stack_slot is negative, but we want to index stack_usage_map
3932 with positive values. */
3933 upper_bound
= -argvec
[argnum
].offset
.constant
+ 1;
3934 lower_bound
= upper_bound
- argvec
[argnum
].size
.constant
;
3936 lower_bound
= argvec
[argnum
].offset
.constant
;
3937 upper_bound
= lower_bound
+ argvec
[argnum
].size
.constant
;
3940 for (i
= lower_bound
; i
< upper_bound
; i
++)
3941 if (stack_usage_map
[i
]
3942 /* Don't store things in the fixed argument area at this
3943 point; it has already been saved. */
3944 && i
> reg_parm_stack_space
)
3947 if (i
!= upper_bound
)
3949 /* We need to make a save area. See what mode we can make
3951 enum machine_mode save_mode
3952 = mode_for_size (argvec
[argnum
].size
.constant
3960 plus_constant (argblock
,
3961 argvec
[argnum
].offset
.constant
)));
3962 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3964 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3968 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, 0, partial
, reg
, 0,
3969 argblock
, GEN_INT (argvec
[argnum
].offset
.constant
),
3970 reg_parm_stack_space
, ARGS_SIZE_RTX (alignment_pad
));
3972 /* Now mark the segment we just used. */
3973 if (ACCUMULATE_OUTGOING_ARGS
)
3974 for (i
= lower_bound
; i
< upper_bound
; i
++)
3975 stack_usage_map
[i
] = 1;
3981 /* If we pushed args in forward order, perform stack alignment
3982 after pushing the last arg. */
3983 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3984 anti_adjust_stack (GEN_INT (args_size
.constant
3985 - original_args_size
.constant
));
3987 if (PUSH_ARGS_REVERSED
)
3992 fun
= prepare_call_address (fun
, NULL_TREE
, &call_fusage
, 0, 0);
3994 /* Now load any reg parms into their regs. */
3996 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3997 are to be pushed. */
3998 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
4000 rtx val
= argvec
[argnum
].value
;
4001 rtx reg
= argvec
[argnum
].reg
;
4002 int partial
= argvec
[argnum
].partial
;
4004 /* Handle calls that pass values in multiple non-contiguous
4005 locations. The PA64 has examples of this for library calls. */
4006 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
4007 emit_group_load (reg
, val
,
4008 GET_MODE_SIZE (GET_MODE (val
)),
4009 GET_MODE_ALIGNMENT (GET_MODE (val
)));
4010 else if (reg
!= 0 && partial
== 0)
4011 emit_move_insn (reg
, val
);
4016 /* Any regs containing parms remain in use through the call. */
4017 for (count
= 0; count
< nargs
; count
++)
4019 rtx reg
= argvec
[count
].reg
;
4020 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
4021 use_group_regs (&call_fusage
, reg
);
4023 use_reg (&call_fusage
, reg
);
4026 /* Pass the function the address in which to return a structure value. */
4027 if (mem_value
!= 0 && struct_value_rtx
!= 0 && ! pcc_struct_value
)
4029 emit_move_insn (struct_value_rtx
,
4031 force_operand (XEXP (mem_value
, 0),
4033 if (GET_CODE (struct_value_rtx
) == REG
)
4034 use_reg (&call_fusage
, struct_value_rtx
);
4037 /* Don't allow popping to be deferred, since then
4038 cse'ing of library calls could delete a call and leave the pop. */
4040 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
4041 ? hard_libcall_value (outmode
) : NULL_RTX
);
4043 /* Stack must be properly aligned now. */
4044 if (stack_pointer_delta
& (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1))
4047 before_call
= get_last_insn ();
4049 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4050 will set inhibit_defer_pop to that value. */
4051 /* The return type is needed to decide how many bytes the function pops.
4052 Signedness plays no role in that, so for simplicity, we pretend it's
4053 always signed. We also assume that the list of arguments passed has
4054 no impact, so we pretend it is unknown. */
4057 get_identifier (XSTR (orgfun
, 0)),
4058 build_function_type (outmode
== VOIDmode
? void_type_node
4059 : type_for_mode (outmode
, 0), NULL_TREE
),
4060 original_args_size
.constant
, args_size
.constant
,
4062 FUNCTION_ARG (args_so_far
, VOIDmode
, void_type_node
, 1),
4064 old_inhibit_defer_pop
+ 1, call_fusage
, flags
);
4066 /* For calls to `setjmp', etc., inform flow.c it should complain
4067 if nonvolatile values are live. For functions that cannot return,
4068 inform flow that control does not fall through. */
4070 if (flags
& (ECF_NORETURN
| ECF_LONGJMP
))
4072 /* The barrier note must be emitted
4073 immediately after the CALL_INSN. Some ports emit more than
4074 just a CALL_INSN above, so we must search for it here. */
4076 rtx last
= get_last_insn ();
4077 while (GET_CODE (last
) != CALL_INSN
)
4079 last
= PREV_INSN (last
);
4080 /* There was no CALL_INSN? */
4081 if (last
== before_call
)
4085 emit_barrier_after (last
);
4088 /* Now restore inhibit_defer_pop to its actual original value. */
4091 /* If call is cse'able, make appropriate pair of reg-notes around it.
4092 Test valreg so we don't crash; may safely ignore `const'
4093 if return type is void. Disable for PARALLEL return values, because
4094 we have no way to move such values into a pseudo register. */
4095 if ((flags
& (ECF_CONST
| ECF_PURE
))
4096 && valreg
!= 0 && GET_CODE (valreg
) != PARALLEL
)
4099 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
4103 /* Construct an "equal form" for the value which mentions all the
4104 arguments in order as well as the function name. */
4105 for (i
= 0; i
< nargs
; i
++)
4106 note
= gen_rtx_EXPR_LIST (VOIDmode
, argvec
[i
].value
, note
);
4107 note
= gen_rtx_EXPR_LIST (VOIDmode
, fun
, note
);
4109 insns
= get_insns ();
4112 if (flags
& ECF_PURE
)
4113 note
= gen_rtx_EXPR_LIST (VOIDmode
,
4114 gen_rtx_USE (VOIDmode
,
4115 gen_rtx_MEM (BLKmode
,
4116 gen_rtx_SCRATCH (VOIDmode
))), note
);
4118 emit_libcall_block (insns
, temp
, valreg
, note
);
4122 else if (flags
& (ECF_CONST
| ECF_PURE
))
4124 /* Otherwise, just write out the sequence without a note. */
4125 rtx insns
= get_insns ();
4132 /* Copy the value to the right place. */
4133 if (outmode
!= VOIDmode
&& retval
)
4139 if (value
!= mem_value
)
4140 emit_move_insn (value
, mem_value
);
4142 else if (value
!= 0)
4143 emit_move_insn (value
, hard_libcall_value (outmode
));
4145 value
= hard_libcall_value (outmode
);
4148 if (ACCUMULATE_OUTGOING_ARGS
)
4150 #ifdef REG_PARM_STACK_SPACE
4153 enum machine_mode save_mode
= GET_MODE (save_area
);
4154 #ifdef ARGS_GROW_DOWNWARD
4156 = gen_rtx_MEM (save_mode
,
4157 memory_address (save_mode
,
4158 plus_constant (argblock
,
4162 = gen_rtx_MEM (save_mode
,
4163 memory_address (save_mode
,
4164 plus_constant (argblock
, low_to_save
)));
4167 set_mem_align (stack_area
, PARM_BOUNDARY
);
4168 if (save_mode
!= BLKmode
)
4169 emit_move_insn (stack_area
, save_area
);
4171 emit_block_move (stack_area
, validize_mem (save_area
),
4172 GEN_INT (high_to_save
- low_to_save
+ 1));
4176 /* If we saved any argument areas, restore them. */
4177 for (count
= 0; count
< nargs
; count
++)
4178 if (argvec
[count
].save_area
)
4180 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
4182 = gen_rtx_MEM (save_mode
,
4185 plus_constant (argblock
,
4186 argvec
[count
].offset
.constant
)));
4188 emit_move_insn (stack_area
, argvec
[count
].save_area
);
4191 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4192 stack_usage_map
= initial_stack_usage_map
;
4199 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4200 (emitting the queue unless NO_QUEUE is nonzero),
4201 for a value of mode OUTMODE,
4202 with NARGS different arguments, passed as alternating rtx values
4203 and machine_modes to convert them to.
4204 The rtx values should have been passed through protect_from_queue already.
4206 FN_TYPE will be zero for `normal' calls, one for `const' calls,
4207 which will be enclosed in REG_LIBCALL/REG_RETVAL notes, and two for
4208 `pure' calls, that are handled like `const' calls with extra
4209 (use (memory (scratch)). */
4212 emit_library_call
VPARAMS((rtx orgfun
, enum libcall_type fn_type
,
4213 enum machine_mode outmode
, int nargs
, ...))
4216 VA_FIXEDARG (p
, rtx
, orgfun
);
4217 VA_FIXEDARG (p
, int, fn_type
);
4218 VA_FIXEDARG (p
, enum machine_mode
, outmode
);
4219 VA_FIXEDARG (p
, int, nargs
);
4221 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
4226 /* Like emit_library_call except that an extra argument, VALUE,
4227 comes second and says where to store the result.
4228 (If VALUE is zero, this function chooses a convenient way
4229 to return the value.
4231 This function returns an rtx for where the value is to be found.
4232 If VALUE is nonzero, VALUE is returned. */
4235 emit_library_call_value
VPARAMS((rtx orgfun
, rtx value
,
4236 enum libcall_type fn_type
,
4237 enum machine_mode outmode
, int nargs
, ...))
4242 VA_FIXEDARG (p
, rtx
, orgfun
);
4243 VA_FIXEDARG (p
, rtx
, value
);
4244 VA_FIXEDARG (p
, int, fn_type
);
4245 VA_FIXEDARG (p
, enum machine_mode
, outmode
);
4246 VA_FIXEDARG (p
, int, nargs
);
4248 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
4256 /* Store a single argument for a function call
4257 into the register or memory area where it must be passed.
4258 *ARG describes the argument value and where to pass it.
4260 ARGBLOCK is the address of the stack-block for all the arguments,
4261 or 0 on a machine where arguments are pushed individually.
4263 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4264 so must be careful about how the stack is used.
4266 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4267 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4268 that we need not worry about saving and restoring the stack.
4270 FNDECL is the declaration of the function we are calling.
4272 Return non-zero if this arg should cause sibcall failure,
4276 store_one_arg (arg
, argblock
, flags
, variable_size
, reg_parm_stack_space
)
4277 struct arg_data
*arg
;
4280 int variable_size ATTRIBUTE_UNUSED
;
4281 int reg_parm_stack_space
;
4283 tree pval
= arg
->tree_value
;
4287 int i
, lower_bound
= 0, upper_bound
= 0;
4288 int sibcall_failure
= 0;
4290 if (TREE_CODE (pval
) == ERROR_MARK
)
4293 /* Push a new temporary level for any temporaries we make for
4297 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4299 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4300 save any previous data at that location. */
4301 if (argblock
&& ! variable_size
&& arg
->stack
)
4303 #ifdef ARGS_GROW_DOWNWARD
4304 /* stack_slot is negative, but we want to index stack_usage_map
4305 with positive values. */
4306 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4307 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4311 lower_bound
= upper_bound
- arg
->size
.constant
;
4313 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4314 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4318 upper_bound
= lower_bound
+ arg
->size
.constant
;
4321 for (i
= lower_bound
; i
< upper_bound
; i
++)
4322 if (stack_usage_map
[i
]
4323 /* Don't store things in the fixed argument area at this point;
4324 it has already been saved. */
4325 && i
> reg_parm_stack_space
)
4328 if (i
!= upper_bound
)
4330 /* We need to make a save area. See what mode we can make it. */
4331 enum machine_mode save_mode
4332 = mode_for_size (arg
->size
.constant
* BITS_PER_UNIT
, MODE_INT
, 1);
4334 = gen_rtx_MEM (save_mode
,
4335 memory_address (save_mode
,
4336 XEXP (arg
->stack_slot
, 0)));
4338 if (save_mode
== BLKmode
)
4340 tree ot
= TREE_TYPE (arg
->tree_value
);
4341 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4342 | TYPE_QUAL_CONST
));
4344 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4345 preserve_temp_slots (arg
->save_area
);
4346 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4347 expr_size (arg
->tree_value
));
4351 arg
->save_area
= gen_reg_rtx (save_mode
);
4352 emit_move_insn (arg
->save_area
, stack_area
);
4356 /* Now that we have saved any slots that will be overwritten by this
4357 store, mark all slots this store will use. We must do this before
4358 we actually expand the argument since the expansion itself may
4359 trigger library calls which might need to use the same stack slot. */
4360 if (argblock
&& ! variable_size
&& arg
->stack
)
4361 for (i
= lower_bound
; i
< upper_bound
; i
++)
4362 stack_usage_map
[i
] = 1;
4365 /* If this isn't going to be placed on both the stack and in registers,
4366 set up the register and number of words. */
4367 if (! arg
->pass_on_stack
)
4368 reg
= arg
->reg
, partial
= arg
->partial
;
4370 if (reg
!= 0 && partial
== 0)
4371 /* Being passed entirely in a register. We shouldn't be called in
4375 /* If this arg needs special alignment, don't load the registers
4377 if (arg
->n_aligned_regs
!= 0)
4380 /* If this is being passed partially in a register, we can't evaluate
4381 it directly into its stack slot. Otherwise, we can. */
4382 if (arg
->value
== 0)
4384 /* stack_arg_under_construction is nonzero if a function argument is
4385 being evaluated directly into the outgoing argument list and
4386 expand_call must take special action to preserve the argument list
4387 if it is called recursively.
4389 For scalar function arguments stack_usage_map is sufficient to
4390 determine which stack slots must be saved and restored. Scalar
4391 arguments in general have pass_on_stack == 0.
4393 If this argument is initialized by a function which takes the
4394 address of the argument (a C++ constructor or a C function
4395 returning a BLKmode structure), then stack_usage_map is
4396 insufficient and expand_call must push the stack around the
4397 function call. Such arguments have pass_on_stack == 1.
4399 Note that it is always safe to set stack_arg_under_construction,
4400 but this generates suboptimal code if set when not needed. */
4402 if (arg
->pass_on_stack
)
4403 stack_arg_under_construction
++;
4405 arg
->value
= expand_expr (pval
,
4407 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4408 ? NULL_RTX
: arg
->stack
,
4411 /* If we are promoting object (or for any other reason) the mode
4412 doesn't agree, convert the mode. */
4414 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4415 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4416 arg
->value
, arg
->unsignedp
);
4418 if (arg
->pass_on_stack
)
4419 stack_arg_under_construction
--;
4422 /* Don't allow anything left on stack from computation
4423 of argument to alloca. */
4424 if (flags
& ECF_MAY_BE_ALLOCA
)
4425 do_pending_stack_adjust ();
4427 if (arg
->value
== arg
->stack
)
4429 /* If the value is already in the stack slot, we are done. */
4430 if (current_function_check_memory_usage
&& GET_CODE (arg
->stack
) == MEM
)
4432 emit_library_call (chkr_set_right_libfunc
, LCT_CONST_MAKE_BLOCK
,
4433 VOIDmode
, 3, XEXP (arg
->stack
, 0), Pmode
,
4434 ARGS_SIZE_RTX (arg
->size
),
4435 TYPE_MODE (sizetype
),
4436 GEN_INT (MEMORY_USE_RW
),
4437 TYPE_MODE (integer_type_node
));
4440 else if (arg
->mode
!= BLKmode
)
4444 /* Argument is a scalar, not entirely passed in registers.
4445 (If part is passed in registers, arg->partial says how much
4446 and emit_push_insn will take care of putting it there.)
4448 Push it, and if its size is less than the
4449 amount of space allocated to it,
4450 also bump stack pointer by the additional space.
4451 Note that in C the default argument promotions
4452 will prevent such mismatches. */
4454 size
= GET_MODE_SIZE (arg
->mode
);
4455 /* Compute how much space the push instruction will push.
4456 On many machines, pushing a byte will advance the stack
4457 pointer by a halfword. */
4458 #ifdef PUSH_ROUNDING
4459 size
= PUSH_ROUNDING (size
);
4463 /* Compute how much space the argument should get:
4464 round up to a multiple of the alignment for arguments. */
4465 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4466 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4467 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4468 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4470 /* This isn't already where we want it on the stack, so put it there.
4471 This can either be done with push or copy insns. */
4472 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
, 0,
4473 partial
, reg
, used
- size
, argblock
,
4474 ARGS_SIZE_RTX (arg
->offset
), reg_parm_stack_space
,
4475 ARGS_SIZE_RTX (arg
->alignment_pad
));
4479 /* BLKmode, at least partly to be pushed. */
4484 /* Pushing a nonscalar.
4485 If part is passed in registers, PARTIAL says how much
4486 and emit_push_insn will take care of putting it there. */
4488 /* Round its size up to a multiple
4489 of the allocation unit for arguments. */
4491 if (arg
->size
.var
!= 0)
4494 size_rtx
= ARGS_SIZE_RTX (arg
->size
);
4498 /* PUSH_ROUNDING has no effect on us, because
4499 emit_push_insn for BLKmode is careful to avoid it. */
4500 excess
= (arg
->size
.constant
- int_size_in_bytes (TREE_TYPE (pval
))
4501 + partial
* UNITS_PER_WORD
);
4502 size_rtx
= expr_size (pval
);
4505 if ((flags
& ECF_SIBCALL
) && GET_CODE (arg
->value
) == MEM
)
4507 /* emit_push_insn might not work properly if arg->value and
4508 argblock + arg->offset areas overlap. */
4512 if (XEXP (x
, 0) == current_function_internal_arg_pointer
4513 || (GET_CODE (XEXP (x
, 0)) == PLUS
4514 && XEXP (XEXP (x
, 0), 0) ==
4515 current_function_internal_arg_pointer
4516 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
))
4518 if (XEXP (x
, 0) != current_function_internal_arg_pointer
)
4519 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4521 /* expand_call should ensure this */
4522 if (arg
->offset
.var
|| GET_CODE (size_rtx
) != CONST_INT
)
4525 if (arg
->offset
.constant
> i
)
4527 if (arg
->offset
.constant
< i
+ INTVAL (size_rtx
))
4528 sibcall_failure
= 1;
4530 else if (arg
->offset
.constant
< i
)
4532 if (i
< arg
->offset
.constant
+ INTVAL (size_rtx
))
4533 sibcall_failure
= 1;
4538 /* Special handling is required if part of the parameter lies in the
4539 register parameter area. The argument may be copied into the stack
4540 slot using memcpy(), but the original contents of the register
4541 parameter area will be restored after the memcpy() call.
4543 To ensure that the part that lies in the register parameter area
4544 is copied correctly, we emit a separate push for that part. This
4545 push should be small enough to avoid a call to memcpy(). */
4546 #ifndef STACK_PARMS_IN_REG_PARM_AREA
4547 if (arg
->reg
&& arg
->pass_on_stack
)
4552 if (arg
->offset
.constant
< reg_parm_stack_space
&& arg
->offset
.var
)
4553 error ("variable offset is passed paritially in stack and in reg");
4554 else if (arg
->offset
.constant
< reg_parm_stack_space
&& arg
->size
.var
)
4555 error ("variable size is passed partially in stack and in reg");
4556 else if (arg
->offset
.constant
< reg_parm_stack_space
4557 && ((arg
->offset
.constant
+ arg
->size
.constant
)
4558 > reg_parm_stack_space
))
4560 rtx size_rtx1
= GEN_INT (reg_parm_stack_space
- arg
->offset
.constant
);
4561 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx1
,
4562 TYPE_ALIGN (TREE_TYPE (pval
)), partial
, reg
,
4563 excess
, argblock
, ARGS_SIZE_RTX (arg
->offset
),
4564 reg_parm_stack_space
,
4565 ARGS_SIZE_RTX (arg
->alignment_pad
));
4570 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4571 TYPE_ALIGN (TREE_TYPE (pval
)), partial
, reg
, excess
,
4572 argblock
, ARGS_SIZE_RTX (arg
->offset
),
4573 reg_parm_stack_space
,
4574 ARGS_SIZE_RTX (arg
->alignment_pad
));
4577 /* Unless this is a partially-in-register argument, the argument is now
4580 ??? Note that this can change arg->value from arg->stack to
4581 arg->stack_slot and it matters when they are not the same.
4582 It isn't totally clear that this is correct in all cases. */
4584 arg
->value
= arg
->stack_slot
;
4586 /* Once we have pushed something, pops can't safely
4587 be deferred during the rest of the arguments. */
4590 /* ANSI doesn't require a sequence point here,
4591 but PCC has one, so this will avoid some problems. */
4594 /* Free any temporary slots made in processing this argument. Show
4595 that we might have taken the address of something and pushed that
4597 preserve_temp_slots (NULL_RTX
);
4601 return sibcall_failure
;