1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
24 #include "coretypes.h"
39 #include "langhooks.h"
44 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
45 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
47 /* Data structure and subroutines used within expand_call. */
51 /* Tree node for this argument. */
53 /* Mode for value; TYPE_MODE unless promoted. */
54 enum machine_mode mode
;
55 /* Current RTL value for argument, or 0 if it isn't precomputed. */
57 /* Initially-compute RTL value for argument; only for const functions. */
59 /* Register to pass this argument in, 0 if passed on stack, or an
60 PARALLEL if the arg is to be copied into multiple non-contiguous
63 /* Register to pass this argument in when generating tail call sequence.
64 This is not the same register as for normal calls on machines with
67 /* If REG was promoted from the actual mode of the argument expression,
68 indicates whether the promotion is sign- or zero-extended. */
70 /* Number of registers to use. 0 means put the whole arg in registers.
71 Also 0 if not passed in registers. */
73 /* Nonzero if argument must be passed on stack.
74 Note that some arguments may be passed on the stack
75 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
76 pass_on_stack identifies arguments that *cannot* go in registers. */
78 /* Some fields packaged up for locate_and_pad_parm. */
79 struct locate_and_pad_arg_data locate
;
80 /* Location on the stack at which parameter should be stored. The store
81 has already been done if STACK == VALUE. */
83 /* Location on the stack of the start of this argument slot. This can
84 differ from STACK if this arg pads downward. This location is known
85 to be aligned to FUNCTION_ARG_BOUNDARY. */
87 /* Place that this stack area has been saved, if needed. */
89 /* If an argument's alignment does not permit direct copying into registers,
90 copy in smaller-sized pieces into pseudos. These are stored in a
91 block pointed to by this field. The next field says how many
92 word-sized pseudos we made. */
97 /* A vector of one char per byte of stack space. A byte if nonzero if
98 the corresponding stack location has been used.
99 This vector is used to prevent a function call within an argument from
100 clobbering any stack already set up. */
101 static char *stack_usage_map
;
103 /* Size of STACK_USAGE_MAP. */
104 static int highest_outgoing_arg_in_use
;
106 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
107 stack location's tail call argument has been already stored into the stack.
108 This bitmap is used to prevent sibling call optimization if function tries
109 to use parent's incoming argument slots when they have been already
110 overwritten with tail call arguments. */
111 static sbitmap stored_args_map
;
113 /* stack_arg_under_construction is nonzero when an argument may be
114 initialized with a constructor call (including a C function that
115 returns a BLKmode struct) and expand_call must take special action
116 to make sure the object being constructed does not overlap the
117 argument list for the constructor call. */
118 int stack_arg_under_construction
;
120 static void emit_call_1 (rtx
, tree
, tree
, tree
, HOST_WIDE_INT
, HOST_WIDE_INT
,
121 HOST_WIDE_INT
, rtx
, rtx
, int, rtx
, int,
123 static void precompute_register_parameters (int, struct arg_data
*, int *);
124 static int store_one_arg (struct arg_data
*, rtx
, int, int, int);
125 static void store_unaligned_arguments_into_pseudos (struct arg_data
*, int);
126 static int finalize_must_preallocate (int, int, struct arg_data
*,
128 static void precompute_arguments (int, int, struct arg_data
*);
129 static int compute_argument_block_size (int, struct args_size
*, int);
130 static void initialize_argument_information (int, struct arg_data
*,
131 struct args_size
*, int, tree
,
132 tree
, CUMULATIVE_ARGS
*, int,
133 rtx
*, int *, int *, int *,
135 static void compute_argument_addresses (struct arg_data
*, rtx
, int);
136 static rtx
rtx_for_function_call (tree
, tree
);
137 static void load_register_parameters (struct arg_data
*, int, rtx
*, int,
139 static rtx
emit_library_call_value_1 (int, rtx
, rtx
, enum libcall_type
,
140 enum machine_mode
, int, va_list);
141 static int special_function_p (tree
, int);
142 static int check_sibcall_argument_overlap_1 (rtx
);
143 static int check_sibcall_argument_overlap (rtx
, struct arg_data
*, int);
145 static int combine_pending_stack_adjustment_and_call (int, struct args_size
*,
147 static tree
fix_unsafe_tree (tree
);
148 static bool shift_returned_value (tree
, rtx
*);
150 #ifdef REG_PARM_STACK_SPACE
151 static rtx
save_fixed_argument_area (int, rtx
, int *, int *);
152 static void restore_fixed_argument_area (rtx
, rtx
, int, int);
155 /* Force FUNEXP into a form suitable for the address of a CALL,
156 and return that as an rtx. Also load the static chain register
157 if FNDECL is a nested function.
159 CALL_FUSAGE points to a variable holding the prospective
160 CALL_INSN_FUNCTION_USAGE information. */
163 prepare_call_address (rtx funexp
, rtx static_chain_value
,
164 rtx
*call_fusage
, int reg_parm_seen
, int sibcallp
)
166 funexp
= protect_from_queue (funexp
, 0);
168 /* Make a valid memory address and copy constants through pseudo-regs,
169 but not for a constant address if -fno-function-cse. */
170 if (GET_CODE (funexp
) != SYMBOL_REF
)
171 /* If we are using registers for parameters, force the
172 function address into a register now. */
173 funexp
= ((SMALL_REGISTER_CLASSES
&& reg_parm_seen
)
174 ? force_not_mem (memory_address (FUNCTION_MODE
, funexp
))
175 : memory_address (FUNCTION_MODE
, funexp
));
178 #ifndef NO_FUNCTION_CSE
179 if (optimize
&& ! flag_no_function_cse
)
180 funexp
= force_reg (Pmode
, funexp
);
184 if (static_chain_value
!= 0)
186 emit_move_insn (static_chain_rtx
, static_chain_value
);
188 if (REG_P (static_chain_rtx
))
189 use_reg (call_fusage
, static_chain_rtx
);
195 /* Generate instructions to call function FUNEXP,
196 and optionally pop the results.
197 The CALL_INSN is the first insn generated.
199 FNDECL is the declaration node of the function. This is given to the
200 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
202 FUNTYPE is the data type of the function. This is given to the macro
203 RETURN_POPS_ARGS to determine whether this function pops its own args.
204 We used to allow an identifier for library functions, but that doesn't
205 work when the return type is an aggregate type and the calling convention
206 says that the pointer to this aggregate is to be popped by the callee.
208 STACK_SIZE is the number of bytes of arguments on the stack,
209 ROUNDED_STACK_SIZE is that number rounded up to
210 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
211 both to put into the call insn and to generate explicit popping
214 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
215 It is zero if this call doesn't want a structure value.
217 NEXT_ARG_REG is the rtx that results from executing
218 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
219 just after all the args have had their registers assigned.
220 This could be whatever you like, but normally it is the first
221 arg-register beyond those used for args in this call,
222 or 0 if all the arg-registers are used in this call.
223 It is passed on to `gen_call' so you can put this info in the call insn.
225 VALREG is a hard register in which a value is returned,
226 or 0 if the call does not return a value.
228 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
229 the args to this call were processed.
230 We restore `inhibit_defer_pop' to that value.
232 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
233 denote registers used by the called function. */
236 emit_call_1 (rtx funexp
, tree fntree
, tree fndecl ATTRIBUTE_UNUSED
,
237 tree funtype ATTRIBUTE_UNUSED
,
238 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED
,
239 HOST_WIDE_INT rounded_stack_size
,
240 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED
,
241 rtx next_arg_reg ATTRIBUTE_UNUSED
, rtx valreg
,
242 int old_inhibit_defer_pop
, rtx call_fusage
, int ecf_flags
,
243 CUMULATIVE_ARGS
*args_so_far ATTRIBUTE_UNUSED
)
245 rtx rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
247 int already_popped
= 0;
248 HOST_WIDE_INT n_popped
= RETURN_POPS_ARGS (fndecl
, funtype
, stack_size
);
249 #if defined (HAVE_call) && defined (HAVE_call_value)
250 rtx struct_value_size_rtx
;
251 struct_value_size_rtx
= GEN_INT (struct_value_size
);
254 #ifdef CALL_POPS_ARGS
255 n_popped
+= CALL_POPS_ARGS (* args_so_far
);
258 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
259 and we don't want to load it into a register as an optimization,
260 because prepare_call_address already did it if it should be done. */
261 if (GET_CODE (funexp
) != SYMBOL_REF
)
262 funexp
= memory_address (FUNCTION_MODE
, funexp
);
264 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
265 if ((ecf_flags
& ECF_SIBCALL
)
266 && HAVE_sibcall_pop
&& HAVE_sibcall_value_pop
267 && (n_popped
> 0 || stack_size
== 0))
269 rtx n_pop
= GEN_INT (n_popped
);
272 /* If this subroutine pops its own args, record that in the call insn
273 if possible, for the sake of frame pointer elimination. */
276 pat
= GEN_SIBCALL_VALUE_POP (valreg
,
277 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
278 rounded_stack_size_rtx
, next_arg_reg
,
281 pat
= GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
282 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
284 emit_call_insn (pat
);
290 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
291 /* If the target has "call" or "call_value" insns, then prefer them
292 if no arguments are actually popped. If the target does not have
293 "call" or "call_value" insns, then we must use the popping versions
294 even if the call has no arguments to pop. */
295 #if defined (HAVE_call) && defined (HAVE_call_value)
296 if (HAVE_call
&& HAVE_call_value
&& HAVE_call_pop
&& HAVE_call_value_pop
297 && n_popped
> 0 && ! (ecf_flags
& ECF_SP_DEPRESSED
))
299 if (HAVE_call_pop
&& HAVE_call_value_pop
)
302 rtx n_pop
= GEN_INT (n_popped
);
305 /* If this subroutine pops its own args, record that in the call insn
306 if possible, for the sake of frame pointer elimination. */
309 pat
= GEN_CALL_VALUE_POP (valreg
,
310 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
311 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
313 pat
= GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
314 rounded_stack_size_rtx
, next_arg_reg
, n_pop
);
316 emit_call_insn (pat
);
322 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
323 if ((ecf_flags
& ECF_SIBCALL
)
324 && HAVE_sibcall
&& HAVE_sibcall_value
)
327 emit_call_insn (GEN_SIBCALL_VALUE (valreg
,
328 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
329 rounded_stack_size_rtx
,
330 next_arg_reg
, NULL_RTX
));
332 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
333 rounded_stack_size_rtx
, next_arg_reg
,
334 struct_value_size_rtx
));
339 #if defined (HAVE_call) && defined (HAVE_call_value)
340 if (HAVE_call
&& HAVE_call_value
)
343 emit_call_insn (GEN_CALL_VALUE (valreg
,
344 gen_rtx_MEM (FUNCTION_MODE
, funexp
),
345 rounded_stack_size_rtx
, next_arg_reg
,
348 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE
, funexp
),
349 rounded_stack_size_rtx
, next_arg_reg
,
350 struct_value_size_rtx
));
356 /* Find the call we just emitted. */
357 call_insn
= last_call_insn ();
359 /* Mark memory as used for "pure" function call. */
360 if (ecf_flags
& ECF_PURE
)
364 gen_rtx_USE (VOIDmode
,
365 gen_rtx_MEM (BLKmode
, gen_rtx_SCRATCH (VOIDmode
))),
368 /* Put the register usage information there. */
369 add_function_usage_to (call_insn
, call_fusage
);
371 /* If this is a const call, then set the insn's unchanging bit. */
372 if (ecf_flags
& (ECF_CONST
| ECF_PURE
))
373 CONST_OR_PURE_CALL_P (call_insn
) = 1;
375 /* If this call can't throw, attach a REG_EH_REGION reg note to that
377 if (ecf_flags
& ECF_NOTHROW
)
378 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_EH_REGION
, const0_rtx
,
379 REG_NOTES (call_insn
));
382 int rn
= lookup_stmt_eh_region (fntree
);
384 /* If rn < 0, then either (1) tree-ssa not used or (2) doesn't
385 throw, which we already took care of. */
387 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_EH_REGION
, GEN_INT (rn
),
388 REG_NOTES (call_insn
));
389 note_current_region_may_contain_throw ();
392 if (ecf_flags
& ECF_NORETURN
)
393 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_NORETURN
, const0_rtx
,
394 REG_NOTES (call_insn
));
395 if (ecf_flags
& ECF_ALWAYS_RETURN
)
396 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN
, const0_rtx
,
397 REG_NOTES (call_insn
));
399 if (ecf_flags
& ECF_RETURNS_TWICE
)
401 REG_NOTES (call_insn
) = gen_rtx_EXPR_LIST (REG_SETJMP
, const0_rtx
,
402 REG_NOTES (call_insn
));
403 current_function_calls_setjmp
= 1;
406 SIBLING_CALL_P (call_insn
) = ((ecf_flags
& ECF_SIBCALL
) != 0);
408 /* Restore this now, so that we do defer pops for this call's args
409 if the context of the call as a whole permits. */
410 inhibit_defer_pop
= old_inhibit_defer_pop
;
415 CALL_INSN_FUNCTION_USAGE (call_insn
)
416 = gen_rtx_EXPR_LIST (VOIDmode
,
417 gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
),
418 CALL_INSN_FUNCTION_USAGE (call_insn
));
419 rounded_stack_size
-= n_popped
;
420 rounded_stack_size_rtx
= GEN_INT (rounded_stack_size
);
421 stack_pointer_delta
-= n_popped
;
424 if (!ACCUMULATE_OUTGOING_ARGS
)
426 /* If returning from the subroutine does not automatically pop the args,
427 we need an instruction to pop them sooner or later.
428 Perhaps do it now; perhaps just record how much space to pop later.
430 If returning from the subroutine does pop the args, indicate that the
431 stack pointer will be changed. */
433 if (rounded_stack_size
!= 0)
435 if (ecf_flags
& (ECF_SP_DEPRESSED
| ECF_NORETURN
| ECF_LONGJMP
))
436 /* Just pretend we did the pop. */
437 stack_pointer_delta
-= rounded_stack_size
;
438 else if (flag_defer_pop
&& inhibit_defer_pop
== 0
439 && ! (ecf_flags
& (ECF_CONST
| ECF_PURE
)))
440 pending_stack_adjust
+= rounded_stack_size
;
442 adjust_stack (rounded_stack_size_rtx
);
445 /* When we accumulate outgoing args, we must avoid any stack manipulations.
446 Restore the stack pointer to its original value now. Usually
447 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
448 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
449 popping variants of functions exist as well.
451 ??? We may optimize similar to defer_pop above, but it is
452 probably not worthwhile.
454 ??? It will be worthwhile to enable combine_stack_adjustments even for
457 anti_adjust_stack (GEN_INT (n_popped
));
460 /* Determine if the function identified by NAME and FNDECL is one with
461 special properties we wish to know about.
463 For example, if the function might return more than one time (setjmp), then
464 set RETURNS_TWICE to a nonzero value.
466 Similarly set LONGJMP for if the function is in the longjmp family.
468 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
469 space from the stack such as alloca. */
472 special_function_p (tree fndecl
, int flags
)
474 if (fndecl
&& DECL_NAME (fndecl
)
475 && IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) <= 17
476 /* Exclude functions not at the file scope, or not `extern',
477 since they are not the magic functions we would otherwise
479 FIXME: this should be handled with attributes, not with this
480 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
481 because you can declare fork() inside a function if you
483 && (DECL_CONTEXT (fndecl
) == NULL_TREE
484 || TREE_CODE (DECL_CONTEXT (fndecl
)) == TRANSLATION_UNIT_DECL
)
485 && TREE_PUBLIC (fndecl
))
487 const char *name
= IDENTIFIER_POINTER (DECL_NAME (fndecl
));
488 const char *tname
= name
;
490 /* We assume that alloca will always be called by name. It
491 makes no sense to pass it as a pointer-to-function to
492 anything that does not understand its behavior. */
493 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 6
495 && ! strcmp (name
, "alloca"))
496 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl
)) == 16
498 && ! strcmp (name
, "__builtin_alloca"))))
499 flags
|= ECF_MAY_BE_ALLOCA
;
501 /* Disregard prefix _, __ or __x. */
504 if (name
[1] == '_' && name
[2] == 'x')
506 else if (name
[1] == '_')
515 && (! strcmp (tname
, "setjmp")
516 || ! strcmp (tname
, "setjmp_syscall")))
518 && ! strcmp (tname
, "sigsetjmp"))
520 && ! strcmp (tname
, "savectx")))
521 flags
|= ECF_RETURNS_TWICE
;
524 && ! strcmp (tname
, "siglongjmp"))
525 flags
|= ECF_LONGJMP
;
527 else if ((tname
[0] == 'q' && tname
[1] == 's'
528 && ! strcmp (tname
, "qsetjmp"))
529 || (tname
[0] == 'v' && tname
[1] == 'f'
530 && ! strcmp (tname
, "vfork")))
531 flags
|= ECF_RETURNS_TWICE
;
533 else if (tname
[0] == 'l' && tname
[1] == 'o'
534 && ! strcmp (tname
, "longjmp"))
535 flags
|= ECF_LONGJMP
;
541 /* Return nonzero when tree represent call to longjmp. */
544 setjmp_call_p (tree fndecl
)
546 return special_function_p (fndecl
, 0) & ECF_RETURNS_TWICE
;
549 /* Return true when exp contains alloca call. */
551 alloca_call_p (tree exp
)
553 if (TREE_CODE (exp
) == CALL_EXPR
554 && TREE_CODE (TREE_OPERAND (exp
, 0)) == ADDR_EXPR
555 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0))
557 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp
, 0), 0),
558 0) & ECF_MAY_BE_ALLOCA
))
563 /* Detect flags (function attributes) from the function decl or type node. */
566 flags_from_decl_or_type (tree exp
)
573 struct cgraph_rtl_info
*i
= cgraph_rtl_info (exp
);
574 type
= TREE_TYPE (exp
);
578 if (i
->pure_function
)
579 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
580 if (i
->const_function
)
581 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
584 /* The function exp may have the `malloc' attribute. */
585 if (DECL_IS_MALLOC (exp
))
588 /* The function exp may have the `pure' attribute. */
589 if (DECL_IS_PURE (exp
))
590 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
592 if (TREE_NOTHROW (exp
))
593 flags
|= ECF_NOTHROW
;
595 if (TREE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
596 flags
|= ECF_LIBCALL_BLOCK
| ECF_CONST
;
598 flags
= special_function_p (exp
, flags
);
600 else if (TYPE_P (exp
) && TYPE_READONLY (exp
) && ! TREE_THIS_VOLATILE (exp
))
603 if (TREE_THIS_VOLATILE (exp
))
604 flags
|= ECF_NORETURN
;
606 /* Mark if the function returns with the stack pointer depressed. We
607 cannot consider it pure or constant in that case. */
608 if (TREE_CODE (type
) == FUNCTION_TYPE
&& TYPE_RETURNS_STACK_DEPRESSED (type
))
610 flags
|= ECF_SP_DEPRESSED
;
611 flags
&= ~(ECF_PURE
| ECF_CONST
| ECF_LIBCALL_BLOCK
);
617 /* Detect flags from a CALL_EXPR. */
620 call_expr_flags (tree t
)
623 tree decl
= get_callee_fndecl (t
);
626 flags
= flags_from_decl_or_type (decl
);
629 t
= TREE_TYPE (TREE_OPERAND (t
, 0));
630 if (t
&& TREE_CODE (t
) == POINTER_TYPE
)
631 flags
= flags_from_decl_or_type (TREE_TYPE (t
));
639 /* Precompute all register parameters as described by ARGS, storing values
640 into fields within the ARGS array.
642 NUM_ACTUALS indicates the total number elements in the ARGS array.
644 Set REG_PARM_SEEN if we encounter a register parameter. */
647 precompute_register_parameters (int num_actuals
, struct arg_data
*args
, int *reg_parm_seen
)
653 for (i
= 0; i
< num_actuals
; i
++)
654 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
)
658 if (args
[i
].value
== 0)
661 args
[i
].value
= expand_expr (args
[i
].tree_value
, NULL_RTX
,
663 preserve_temp_slots (args
[i
].value
);
666 /* ANSI doesn't require a sequence point here,
667 but PCC has one, so this will avoid some problems. */
671 /* If the value is a non-legitimate constant, force it into a
672 pseudo now. TLS symbols sometimes need a call to resolve. */
673 if (CONSTANT_P (args
[i
].value
)
674 && !LEGITIMATE_CONSTANT_P (args
[i
].value
))
675 args
[i
].value
= force_reg (args
[i
].mode
, args
[i
].value
);
677 /* If we are to promote the function arg to a wider mode,
680 if (args
[i
].mode
!= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)))
682 = convert_modes (args
[i
].mode
,
683 TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)),
684 args
[i
].value
, args
[i
].unsignedp
);
686 /* If the value is expensive, and we are inside an appropriately
687 short loop, put the value into a pseudo and then put the pseudo
690 For small register classes, also do this if this call uses
691 register parameters. This is to avoid reload conflicts while
692 loading the parameters registers. */
694 if ((! (REG_P (args
[i
].value
)
695 || (GET_CODE (args
[i
].value
) == SUBREG
696 && REG_P (SUBREG_REG (args
[i
].value
)))))
697 && args
[i
].mode
!= BLKmode
698 && rtx_cost (args
[i
].value
, SET
) > COSTS_N_INSNS (1)
699 && ((SMALL_REGISTER_CLASSES
&& *reg_parm_seen
)
700 || preserve_subexpressions_p ()))
701 args
[i
].value
= copy_to_mode_reg (args
[i
].mode
, args
[i
].value
);
705 #ifdef REG_PARM_STACK_SPACE
707 /* The argument list is the property of the called routine and it
708 may clobber it. If the fixed area has been used for previous
709 parameters, we must save and restore it. */
712 save_fixed_argument_area (int reg_parm_stack_space
, rtx argblock
, int *low_to_save
, int *high_to_save
)
717 /* Compute the boundary of the area that needs to be saved, if any. */
718 high
= reg_parm_stack_space
;
719 #ifdef ARGS_GROW_DOWNWARD
722 if (high
> highest_outgoing_arg_in_use
)
723 high
= highest_outgoing_arg_in_use
;
725 for (low
= 0; low
< high
; low
++)
726 if (stack_usage_map
[low
] != 0)
729 enum machine_mode save_mode
;
734 while (stack_usage_map
[--high
] == 0)
738 *high_to_save
= high
;
740 num_to_save
= high
- low
+ 1;
741 save_mode
= mode_for_size (num_to_save
* BITS_PER_UNIT
, MODE_INT
, 1);
743 /* If we don't have the required alignment, must do this
745 if ((low
& (MIN (GET_MODE_SIZE (save_mode
),
746 BIGGEST_ALIGNMENT
/ UNITS_PER_WORD
) - 1)))
749 #ifdef ARGS_GROW_DOWNWARD
754 stack_area
= gen_rtx_MEM (save_mode
,
755 memory_address (save_mode
,
756 plus_constant (argblock
,
759 set_mem_align (stack_area
, PARM_BOUNDARY
);
760 if (save_mode
== BLKmode
)
762 save_area
= assign_stack_temp (BLKmode
, num_to_save
, 0);
763 emit_block_move (validize_mem (save_area
), stack_area
,
764 GEN_INT (num_to_save
), BLOCK_OP_CALL_PARM
);
768 save_area
= gen_reg_rtx (save_mode
);
769 emit_move_insn (save_area
, stack_area
);
779 restore_fixed_argument_area (rtx save_area
, rtx argblock
, int high_to_save
, int low_to_save
)
781 enum machine_mode save_mode
= GET_MODE (save_area
);
785 #ifdef ARGS_GROW_DOWNWARD
786 delta
= -high_to_save
;
790 stack_area
= gen_rtx_MEM (save_mode
,
791 memory_address (save_mode
,
792 plus_constant (argblock
, delta
)));
793 set_mem_align (stack_area
, PARM_BOUNDARY
);
795 if (save_mode
!= BLKmode
)
796 emit_move_insn (stack_area
, save_area
);
798 emit_block_move (stack_area
, validize_mem (save_area
),
799 GEN_INT (high_to_save
- low_to_save
+ 1),
802 #endif /* REG_PARM_STACK_SPACE */
804 /* If any elements in ARGS refer to parameters that are to be passed in
805 registers, but not in memory, and whose alignment does not permit a
806 direct copy into registers. Copy the values into a group of pseudos
807 which we will later copy into the appropriate hard registers.
809 Pseudos for each unaligned argument will be stored into the array
810 args[argnum].aligned_regs. The caller is responsible for deallocating
811 the aligned_regs array if it is nonzero. */
814 store_unaligned_arguments_into_pseudos (struct arg_data
*args
, int num_actuals
)
818 for (i
= 0; i
< num_actuals
; i
++)
819 if (args
[i
].reg
!= 0 && ! args
[i
].pass_on_stack
820 && args
[i
].mode
== BLKmode
821 && (TYPE_ALIGN (TREE_TYPE (args
[i
].tree_value
))
822 < (unsigned int) MIN (BIGGEST_ALIGNMENT
, BITS_PER_WORD
)))
824 int bytes
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
825 int nregs
= (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
826 int endian_correction
= 0;
828 args
[i
].n_aligned_regs
= args
[i
].partial
? args
[i
].partial
: nregs
;
829 args
[i
].aligned_regs
= xmalloc (sizeof (rtx
) * args
[i
].n_aligned_regs
);
831 /* Structures smaller than a word are normally aligned to the
832 least significant byte. On a BYTES_BIG_ENDIAN machine,
833 this means we must skip the empty high order bytes when
834 calculating the bit offset. */
835 if (bytes
< UNITS_PER_WORD
836 #ifdef BLOCK_REG_PADDING
837 && (BLOCK_REG_PADDING (args
[i
].mode
,
838 TREE_TYPE (args
[i
].tree_value
), 1)
844 endian_correction
= BITS_PER_WORD
- bytes
* BITS_PER_UNIT
;
846 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
848 rtx reg
= gen_reg_rtx (word_mode
);
849 rtx word
= operand_subword_force (args
[i
].value
, j
, BLKmode
);
850 int bitsize
= MIN (bytes
* BITS_PER_UNIT
, BITS_PER_WORD
);
852 args
[i
].aligned_regs
[j
] = reg
;
853 word
= extract_bit_field (word
, bitsize
, 0, 1, NULL_RTX
,
854 word_mode
, word_mode
, BITS_PER_WORD
);
856 /* There is no need to restrict this code to loading items
857 in TYPE_ALIGN sized hunks. The bitfield instructions can
858 load up entire word sized registers efficiently.
860 ??? This may not be needed anymore.
861 We use to emit a clobber here but that doesn't let later
862 passes optimize the instructions we emit. By storing 0 into
863 the register later passes know the first AND to zero out the
864 bitfield being set in the register is unnecessary. The store
865 of 0 will be deleted as will at least the first AND. */
867 emit_move_insn (reg
, const0_rtx
);
869 bytes
-= bitsize
/ BITS_PER_UNIT
;
870 store_bit_field (reg
, bitsize
, endian_correction
, word_mode
,
871 word
, BITS_PER_WORD
);
876 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
879 NUM_ACTUALS is the total number of parameters.
881 N_NAMED_ARGS is the total number of named arguments.
883 FNDECL is the tree code for the target of this call (if known)
885 ARGS_SO_FAR holds state needed by the target to know where to place
888 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
889 for arguments which are passed in registers.
891 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
892 and may be modified by this routine.
894 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
895 flags which may may be modified by this routine.
897 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
898 that requires allocation of stack space.
900 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
901 the thunked-to function. */
904 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED
,
905 struct arg_data
*args
,
906 struct args_size
*args_size
,
907 int n_named_args ATTRIBUTE_UNUSED
,
908 tree actparms
, tree fndecl
,
909 CUMULATIVE_ARGS
*args_so_far
,
910 int reg_parm_stack_space
,
911 rtx
*old_stack_level
, int *old_pending_adj
,
912 int *must_preallocate
, int *ecf_flags
,
913 bool *may_tailcall
, bool call_from_thunk_p
)
915 /* 1 if scanning parms front to back, -1 if scanning back to front. */
918 /* Count arg position in order args appear. */
924 args_size
->constant
= 0;
927 /* In this loop, we consider args in the order they are written.
928 We fill up ARGS from the front or from the back if necessary
929 so that in any case the first arg to be pushed ends up at the front. */
931 if (PUSH_ARGS_REVERSED
)
933 i
= num_actuals
- 1, inc
= -1;
934 /* In this case, must reverse order of args
935 so that we compute and push the last arg first. */
942 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
943 for (p
= actparms
, argpos
= 0; p
; p
= TREE_CHAIN (p
), i
+= inc
, argpos
++)
945 tree type
= TREE_TYPE (TREE_VALUE (p
));
947 enum machine_mode mode
;
949 args
[i
].tree_value
= TREE_VALUE (p
);
951 /* Replace erroneous argument with constant zero. */
952 if (type
== error_mark_node
|| !COMPLETE_TYPE_P (type
))
953 args
[i
].tree_value
= integer_zero_node
, type
= integer_type_node
;
955 /* If TYPE is a transparent union, pass things the way we would
956 pass the first field of the union. We have already verified that
957 the modes are the same. */
958 if (TREE_CODE (type
) == UNION_TYPE
&& TYPE_TRANSPARENT_UNION (type
))
959 type
= TREE_TYPE (TYPE_FIELDS (type
));
961 /* Decide where to pass this arg.
963 args[i].reg is nonzero if all or part is passed in registers.
965 args[i].partial is nonzero if part but not all is passed in registers,
966 and the exact value says how many words are passed in registers.
968 args[i].pass_on_stack is nonzero if the argument must at least be
969 computed on the stack. It may then be loaded back into registers
970 if args[i].reg is nonzero.
972 These decisions are driven by the FUNCTION_... macros and must agree
973 with those made by function.c. */
975 /* See if this argument should be passed by invisible reference. */
976 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (type
))
977 || TREE_ADDRESSABLE (type
)
978 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far
, TYPE_MODE (type
),
979 type
, argpos
< n_named_args
)
982 /* If we're compiling a thunk, pass through invisible
983 references instead of making a copy. */
984 if (call_from_thunk_p
985 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far
, TYPE_MODE (type
),
986 type
, argpos
< n_named_args
)
987 /* If it's in a register, we must make a copy of it too. */
988 /* ??? Is this a sufficient test? Is there a better one? */
989 && !(TREE_CODE (args
[i
].tree_value
) == VAR_DECL
990 && REG_P (DECL_RTL (args
[i
].tree_value
)))
991 && ! TREE_ADDRESSABLE (type
))
994 /* C++ uses a TARGET_EXPR to indicate that we want to make a
995 new object from the argument. If we are passing by
996 invisible reference, the callee will do that for us, so we
997 can strip off the TARGET_EXPR. This is not always safe,
998 but it is safe in the only case where this is a useful
999 optimization; namely, when the argument is a plain object.
1000 In that case, the frontend is just asking the backend to
1001 make a bitwise copy of the argument. */
1003 if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1004 && (DECL_P (TREE_OPERAND (args
[i
].tree_value
, 1)))
1005 && ! REG_P (DECL_RTL (TREE_OPERAND (args
[i
].tree_value
, 1))))
1006 args
[i
].tree_value
= TREE_OPERAND (args
[i
].tree_value
, 1);
1008 /* We can't use sibcalls if a callee-copied argument is stored
1009 in the current function's frame. */
1010 if (!call_from_thunk_p
1011 && (!DECL_P (args
[i
].tree_value
)
1012 || !TREE_STATIC (args
[i
].tree_value
)))
1013 *may_tailcall
= false;
1015 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1016 build_pointer_type (type
),
1017 args
[i
].tree_value
);
1018 type
= build_pointer_type (type
);
1020 else if (TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
)
1022 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1023 We implement this by passing the address of the temporary
1024 rather than expanding it into another allocated slot. */
1025 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1026 build_pointer_type (type
),
1027 args
[i
].tree_value
);
1028 type
= build_pointer_type (type
);
1029 *may_tailcall
= false;
1033 /* We make a copy of the object and pass the address to the
1034 function being called. */
1037 if (!COMPLETE_TYPE_P (type
)
1038 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1039 || (flag_stack_check
&& ! STACK_CHECK_BUILTIN
1040 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type
),
1041 STACK_CHECK_MAX_VAR_SIZE
))))
1043 /* This is a variable-sized object. Make space on the stack
1045 rtx size_rtx
= expr_size (TREE_VALUE (p
));
1047 if (*old_stack_level
== 0)
1049 emit_stack_save (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
1050 *old_pending_adj
= pending_stack_adjust
;
1051 pending_stack_adjust
= 0;
1054 copy
= gen_rtx_MEM (BLKmode
,
1055 allocate_dynamic_stack_space
1056 (size_rtx
, NULL_RTX
, TYPE_ALIGN (type
)));
1057 set_mem_attributes (copy
, type
, 1);
1060 copy
= assign_temp (type
, 0, 1, 0);
1062 store_expr (args
[i
].tree_value
, copy
, 0);
1063 *ecf_flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
1065 args
[i
].tree_value
= build1 (ADDR_EXPR
,
1066 build_pointer_type (type
),
1067 make_tree (type
, copy
));
1068 type
= build_pointer_type (type
);
1069 *may_tailcall
= false;
1073 mode
= TYPE_MODE (type
);
1074 unsignedp
= TYPE_UNSIGNED (type
);
1076 if (targetm
.calls
.promote_function_args (fndecl
? TREE_TYPE (fndecl
) : 0))
1077 mode
= promote_mode (type
, mode
, &unsignedp
, 1);
1079 args
[i
].unsignedp
= unsignedp
;
1080 args
[i
].mode
= mode
;
1082 args
[i
].reg
= FUNCTION_ARG (*args_so_far
, mode
, type
,
1083 argpos
< n_named_args
);
1084 #ifdef FUNCTION_INCOMING_ARG
1085 /* If this is a sibling call and the machine has register windows, the
1086 register window has to be unwinded before calling the routine, so
1087 arguments have to go into the incoming registers. */
1088 args
[i
].tail_call_reg
= FUNCTION_INCOMING_ARG (*args_so_far
, mode
, type
,
1089 argpos
< n_named_args
);
1091 args
[i
].tail_call_reg
= args
[i
].reg
;
1096 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far
, mode
, type
,
1097 argpos
< n_named_args
);
1099 args
[i
].pass_on_stack
= MUST_PASS_IN_STACK (mode
, type
);
1101 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1102 it means that we are to pass this arg in the register(s) designated
1103 by the PARALLEL, but also to pass it in the stack. */
1104 if (args
[i
].reg
&& GET_CODE (args
[i
].reg
) == PARALLEL
1105 && XEXP (XVECEXP (args
[i
].reg
, 0, 0), 0) == 0)
1106 args
[i
].pass_on_stack
= 1;
1108 /* If this is an addressable type, we must preallocate the stack
1109 since we must evaluate the object into its final location.
1111 If this is to be passed in both registers and the stack, it is simpler
1113 if (TREE_ADDRESSABLE (type
)
1114 || (args
[i
].pass_on_stack
&& args
[i
].reg
!= 0))
1115 *must_preallocate
= 1;
1117 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1118 we cannot consider this function call constant. */
1119 if (TREE_ADDRESSABLE (type
))
1120 *ecf_flags
&= ~ECF_LIBCALL_BLOCK
;
1122 /* Compute the stack-size of this argument. */
1123 if (args
[i
].reg
== 0 || args
[i
].partial
!= 0
1124 || reg_parm_stack_space
> 0
1125 || args
[i
].pass_on_stack
)
1126 locate_and_pad_parm (mode
, type
,
1127 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1132 args
[i
].pass_on_stack
? 0 : args
[i
].partial
,
1133 fndecl
, args_size
, &args
[i
].locate
);
1134 #ifdef BLOCK_REG_PADDING
1136 /* The argument is passed entirely in registers. See at which
1137 end it should be padded. */
1138 args
[i
].locate
.where_pad
=
1139 BLOCK_REG_PADDING (mode
, type
,
1140 int_size_in_bytes (type
) <= UNITS_PER_WORD
);
1143 /* Update ARGS_SIZE, the total stack space for args so far. */
1145 args_size
->constant
+= args
[i
].locate
.size
.constant
;
1146 if (args
[i
].locate
.size
.var
)
1147 ADD_PARM_SIZE (*args_size
, args
[i
].locate
.size
.var
);
1149 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1150 have been used, etc. */
1152 FUNCTION_ARG_ADVANCE (*args_so_far
, TYPE_MODE (type
), type
,
1153 argpos
< n_named_args
);
1157 /* Update ARGS_SIZE to contain the total size for the argument block.
1158 Return the original constant component of the argument block's size.
1160 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1161 for arguments passed in registers. */
1164 compute_argument_block_size (int reg_parm_stack_space
,
1165 struct args_size
*args_size
,
1166 int preferred_stack_boundary ATTRIBUTE_UNUSED
)
1168 int unadjusted_args_size
= args_size
->constant
;
1170 /* For accumulate outgoing args mode we don't need to align, since the frame
1171 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1172 backends from generating misaligned frame sizes. */
1173 if (ACCUMULATE_OUTGOING_ARGS
&& preferred_stack_boundary
> STACK_BOUNDARY
)
1174 preferred_stack_boundary
= STACK_BOUNDARY
;
1176 /* Compute the actual size of the argument block required. The variable
1177 and constant sizes must be combined, the size may have to be rounded,
1178 and there may be a minimum required size. */
1182 args_size
->var
= ARGS_SIZE_TREE (*args_size
);
1183 args_size
->constant
= 0;
1185 preferred_stack_boundary
/= BITS_PER_UNIT
;
1186 if (preferred_stack_boundary
> 1)
1188 /* We don't handle this case yet. To handle it correctly we have
1189 to add the delta, round and subtract the delta.
1190 Currently no machine description requires this support. */
1191 if (stack_pointer_delta
& (preferred_stack_boundary
- 1))
1193 args_size
->var
= round_up (args_size
->var
, preferred_stack_boundary
);
1196 if (reg_parm_stack_space
> 0)
1199 = size_binop (MAX_EXPR
, args_size
->var
,
1200 ssize_int (reg_parm_stack_space
));
1202 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1203 /* The area corresponding to register parameters is not to count in
1204 the size of the block we need. So make the adjustment. */
1206 = size_binop (MINUS_EXPR
, args_size
->var
,
1207 ssize_int (reg_parm_stack_space
));
1213 preferred_stack_boundary
/= BITS_PER_UNIT
;
1214 if (preferred_stack_boundary
< 1)
1215 preferred_stack_boundary
= 1;
1216 args_size
->constant
= (((args_size
->constant
1217 + stack_pointer_delta
1218 + preferred_stack_boundary
- 1)
1219 / preferred_stack_boundary
1220 * preferred_stack_boundary
)
1221 - stack_pointer_delta
);
1223 args_size
->constant
= MAX (args_size
->constant
,
1224 reg_parm_stack_space
);
1226 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1227 args_size
->constant
-= reg_parm_stack_space
;
1230 return unadjusted_args_size
;
1233 /* Precompute parameters as needed for a function call.
1235 FLAGS is mask of ECF_* constants.
1237 NUM_ACTUALS is the number of arguments.
1239 ARGS is an array containing information for each argument; this
1240 routine fills in the INITIAL_VALUE and VALUE fields for each
1241 precomputed argument. */
1244 precompute_arguments (int flags
, int num_actuals
, struct arg_data
*args
)
1248 /* If this is a libcall, then precompute all arguments so that we do not
1249 get extraneous instructions emitted as part of the libcall sequence. */
1250 if ((flags
& ECF_LIBCALL_BLOCK
) == 0)
1253 for (i
= 0; i
< num_actuals
; i
++)
1255 enum machine_mode mode
;
1257 /* If this is an addressable type, we cannot pre-evaluate it. */
1258 if (TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
)))
1262 = expand_expr (args
[i
].tree_value
, NULL_RTX
, VOIDmode
, 0);
1264 /* ANSI doesn't require a sequence point here,
1265 but PCC has one, so this will avoid some problems. */
1268 args
[i
].initial_value
= args
[i
].value
1269 = protect_from_queue (args
[i
].value
, 0);
1271 mode
= TYPE_MODE (TREE_TYPE (args
[i
].tree_value
));
1272 if (mode
!= args
[i
].mode
)
1275 = convert_modes (args
[i
].mode
, mode
,
1276 args
[i
].value
, args
[i
].unsignedp
);
1277 #if defined(PROMOTE_FUNCTION_MODE) && !defined(PROMOTE_MODE)
1278 /* CSE will replace this only if it contains args[i].value
1279 pseudo, so convert it down to the declared mode using
1281 if (REG_P (args
[i
].value
)
1282 && GET_MODE_CLASS (args
[i
].mode
) == MODE_INT
)
1284 args
[i
].initial_value
1285 = gen_lowpart_SUBREG (mode
, args
[i
].value
);
1286 SUBREG_PROMOTED_VAR_P (args
[i
].initial_value
) = 1;
1287 SUBREG_PROMOTED_UNSIGNED_SET (args
[i
].initial_value
,
1295 /* Given the current state of MUST_PREALLOCATE and information about
1296 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1297 compute and return the final value for MUST_PREALLOCATE. */
1300 finalize_must_preallocate (int must_preallocate
, int num_actuals
, struct arg_data
*args
, struct args_size
*args_size
)
1302 /* See if we have or want to preallocate stack space.
1304 If we would have to push a partially-in-regs parm
1305 before other stack parms, preallocate stack space instead.
1307 If the size of some parm is not a multiple of the required stack
1308 alignment, we must preallocate.
1310 If the total size of arguments that would otherwise create a copy in
1311 a temporary (such as a CALL) is more than half the total argument list
1312 size, preallocation is faster.
1314 Another reason to preallocate is if we have a machine (like the m88k)
1315 where stack alignment is required to be maintained between every
1316 pair of insns, not just when the call is made. However, we assume here
1317 that such machines either do not have push insns (and hence preallocation
1318 would occur anyway) or the problem is taken care of with
1321 if (! must_preallocate
)
1323 int partial_seen
= 0;
1324 int copy_to_evaluate_size
= 0;
1327 for (i
= 0; i
< num_actuals
&& ! must_preallocate
; i
++)
1329 if (args
[i
].partial
> 0 && ! args
[i
].pass_on_stack
)
1331 else if (partial_seen
&& args
[i
].reg
== 0)
1332 must_preallocate
= 1;
1334 if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
1335 && (TREE_CODE (args
[i
].tree_value
) == CALL_EXPR
1336 || TREE_CODE (args
[i
].tree_value
) == TARGET_EXPR
1337 || TREE_CODE (args
[i
].tree_value
) == COND_EXPR
1338 || TREE_ADDRESSABLE (TREE_TYPE (args
[i
].tree_value
))))
1339 copy_to_evaluate_size
1340 += int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1343 if (copy_to_evaluate_size
* 2 >= args_size
->constant
1344 && args_size
->constant
> 0)
1345 must_preallocate
= 1;
1347 return must_preallocate
;
1350 /* If we preallocated stack space, compute the address of each argument
1351 and store it into the ARGS array.
1353 We need not ensure it is a valid memory address here; it will be
1354 validized when it is used.
1356 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1359 compute_argument_addresses (struct arg_data
*args
, rtx argblock
, int num_actuals
)
1363 rtx arg_reg
= argblock
;
1364 int i
, arg_offset
= 0;
1366 if (GET_CODE (argblock
) == PLUS
)
1367 arg_reg
= XEXP (argblock
, 0), arg_offset
= INTVAL (XEXP (argblock
, 1));
1369 for (i
= 0; i
< num_actuals
; i
++)
1371 rtx offset
= ARGS_SIZE_RTX (args
[i
].locate
.offset
);
1372 rtx slot_offset
= ARGS_SIZE_RTX (args
[i
].locate
.slot_offset
);
1375 /* Skip this parm if it will not be passed on the stack. */
1376 if (! args
[i
].pass_on_stack
&& args
[i
].reg
!= 0)
1379 if (GET_CODE (offset
) == CONST_INT
)
1380 addr
= plus_constant (arg_reg
, INTVAL (offset
));
1382 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, offset
);
1384 addr
= plus_constant (addr
, arg_offset
);
1385 args
[i
].stack
= gen_rtx_MEM (args
[i
].mode
, addr
);
1386 set_mem_align (args
[i
].stack
, PARM_BOUNDARY
);
1387 set_mem_attributes (args
[i
].stack
,
1388 TREE_TYPE (args
[i
].tree_value
), 1);
1390 if (GET_CODE (slot_offset
) == CONST_INT
)
1391 addr
= plus_constant (arg_reg
, INTVAL (slot_offset
));
1393 addr
= gen_rtx_PLUS (Pmode
, arg_reg
, slot_offset
);
1395 addr
= plus_constant (addr
, arg_offset
);
1396 args
[i
].stack_slot
= gen_rtx_MEM (args
[i
].mode
, addr
);
1397 set_mem_align (args
[i
].stack_slot
, PARM_BOUNDARY
);
1398 set_mem_attributes (args
[i
].stack_slot
,
1399 TREE_TYPE (args
[i
].tree_value
), 1);
1401 /* Function incoming arguments may overlap with sibling call
1402 outgoing arguments and we cannot allow reordering of reads
1403 from function arguments with stores to outgoing arguments
1404 of sibling calls. */
1405 set_mem_alias_set (args
[i
].stack
, 0);
1406 set_mem_alias_set (args
[i
].stack_slot
, 0);
1411 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1412 in a call instruction.
1414 FNDECL is the tree node for the target function. For an indirect call
1415 FNDECL will be NULL_TREE.
1417 ADDR is the operand 0 of CALL_EXPR for this call. */
1420 rtx_for_function_call (tree fndecl
, tree addr
)
1424 /* Get the function to call, in the form of RTL. */
1427 /* If this is the first use of the function, see if we need to
1428 make an external definition for it. */
1429 if (! TREE_USED (fndecl
))
1431 assemble_external (fndecl
);
1432 TREE_USED (fndecl
) = 1;
1435 /* Get a SYMBOL_REF rtx for the function address. */
1436 funexp
= XEXP (DECL_RTL (fndecl
), 0);
1439 /* Generate an rtx (probably a pseudo-register) for the address. */
1442 funexp
= expand_expr (addr
, NULL_RTX
, VOIDmode
, 0);
1443 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1449 /* Do the register loads required for any wholly-register parms or any
1450 parms which are passed both on the stack and in a register. Their
1451 expressions were already evaluated.
1453 Mark all register-parms as living through the call, putting these USE
1454 insns in the CALL_INSN_FUNCTION_USAGE field.
1456 When IS_SIBCALL, perform the check_sibcall_overlap_argument_overlap
1457 checking, setting *SIBCALL_FAILURE if appropriate. */
1460 load_register_parameters (struct arg_data
*args
, int num_actuals
,
1461 rtx
*call_fusage
, int flags
, int is_sibcall
,
1462 int *sibcall_failure
)
1466 for (i
= 0; i
< num_actuals
; i
++)
1468 rtx reg
= ((flags
& ECF_SIBCALL
)
1469 ? args
[i
].tail_call_reg
: args
[i
].reg
);
1472 int partial
= args
[i
].partial
;
1475 rtx before_arg
= get_last_insn ();
1476 /* Set to non-negative if must move a word at a time, even if just
1477 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1478 we just use a normal move insn. This value can be zero if the
1479 argument is a zero size structure with no fields. */
1483 else if (TYPE_MODE (TREE_TYPE (args
[i
].tree_value
)) == BLKmode
)
1485 size
= int_size_in_bytes (TREE_TYPE (args
[i
].tree_value
));
1486 nregs
= (size
+ (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
;
1489 size
= GET_MODE_SIZE (args
[i
].mode
);
1491 /* Handle calls that pass values in multiple non-contiguous
1492 locations. The Irix 6 ABI has examples of this. */
1494 if (GET_CODE (reg
) == PARALLEL
)
1496 tree type
= TREE_TYPE (args
[i
].tree_value
);
1497 emit_group_load (reg
, args
[i
].value
, type
,
1498 int_size_in_bytes (type
));
1501 /* If simple case, just do move. If normal partial, store_one_arg
1502 has already loaded the register for us. In all other cases,
1503 load the register(s) from memory. */
1505 else if (nregs
== -1)
1507 emit_move_insn (reg
, args
[i
].value
);
1508 #ifdef BLOCK_REG_PADDING
1509 /* Handle case where we have a value that needs shifting
1510 up to the msb. eg. a QImode value and we're padding
1511 upward on a BYTES_BIG_ENDIAN machine. */
1512 if (size
< UNITS_PER_WORD
1513 && (args
[i
].locate
.where_pad
1514 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
1517 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1519 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1520 report the whole reg as used. Strictly speaking, the
1521 call only uses SIZE bytes at the msb end, but it doesn't
1522 seem worth generating rtl to say that. */
1523 reg
= gen_rtx_REG (word_mode
, REGNO (reg
));
1524 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
1525 build_int_2 (shift
, 0), reg
, 1);
1527 emit_move_insn (reg
, x
);
1532 /* If we have pre-computed the values to put in the registers in
1533 the case of non-aligned structures, copy them in now. */
1535 else if (args
[i
].n_aligned_regs
!= 0)
1536 for (j
= 0; j
< args
[i
].n_aligned_regs
; j
++)
1537 emit_move_insn (gen_rtx_REG (word_mode
, REGNO (reg
) + j
),
1538 args
[i
].aligned_regs
[j
]);
1540 else if (partial
== 0 || args
[i
].pass_on_stack
)
1542 rtx mem
= validize_mem (args
[i
].value
);
1544 /* Handle a BLKmode that needs shifting. */
1545 if (nregs
== 1 && size
< UNITS_PER_WORD
1546 #ifdef BLOCK_REG_PADDING
1547 && args
[i
].locate
.where_pad
== downward
1553 rtx tem
= operand_subword_force (mem
, 0, args
[i
].mode
);
1554 rtx ri
= gen_rtx_REG (word_mode
, REGNO (reg
));
1555 rtx x
= gen_reg_rtx (word_mode
);
1556 int shift
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
1557 enum tree_code dir
= BYTES_BIG_ENDIAN
? RSHIFT_EXPR
1560 emit_move_insn (x
, tem
);
1561 x
= expand_shift (dir
, word_mode
, x
,
1562 build_int_2 (shift
, 0), ri
, 1);
1564 emit_move_insn (ri
, x
);
1567 move_block_to_reg (REGNO (reg
), mem
, nregs
, args
[i
].mode
);
1570 /* When a parameter is a block, and perhaps in other cases, it is
1571 possible that it did a load from an argument slot that was
1572 already clobbered. */
1574 && check_sibcall_argument_overlap (before_arg
, &args
[i
], 0))
1575 *sibcall_failure
= 1;
1577 /* Handle calls that pass values in multiple non-contiguous
1578 locations. The Irix 6 ABI has examples of this. */
1579 if (GET_CODE (reg
) == PARALLEL
)
1580 use_group_regs (call_fusage
, reg
);
1581 else if (nregs
== -1)
1582 use_reg (call_fusage
, reg
);
1584 use_regs (call_fusage
, REGNO (reg
), nregs
== 0 ? 1 : nregs
);
1589 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1590 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1591 bytes, then we would need to push some additional bytes to pad the
1592 arguments. So, we compute an adjust to the stack pointer for an
1593 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1594 bytes. Then, when the arguments are pushed the stack will be perfectly
1595 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1596 be popped after the call. Returns the adjustment. */
1599 combine_pending_stack_adjustment_and_call (int unadjusted_args_size
,
1600 struct args_size
*args_size
,
1601 int preferred_unit_stack_boundary
)
1603 /* The number of bytes to pop so that the stack will be
1604 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1605 HOST_WIDE_INT adjustment
;
1606 /* The alignment of the stack after the arguments are pushed, if we
1607 just pushed the arguments without adjust the stack here. */
1608 HOST_WIDE_INT unadjusted_alignment
;
1610 unadjusted_alignment
1611 = ((stack_pointer_delta
+ unadjusted_args_size
)
1612 % preferred_unit_stack_boundary
);
1614 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1615 as possible -- leaving just enough left to cancel out the
1616 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1617 PENDING_STACK_ADJUST is non-negative, and congruent to
1618 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1620 /* Begin by trying to pop all the bytes. */
1621 unadjusted_alignment
1622 = (unadjusted_alignment
1623 - (pending_stack_adjust
% preferred_unit_stack_boundary
));
1624 adjustment
= pending_stack_adjust
;
1625 /* Push enough additional bytes that the stack will be aligned
1626 after the arguments are pushed. */
1627 if (preferred_unit_stack_boundary
> 1)
1629 if (unadjusted_alignment
> 0)
1630 adjustment
-= preferred_unit_stack_boundary
- unadjusted_alignment
;
1632 adjustment
+= unadjusted_alignment
;
1635 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1636 bytes after the call. The right number is the entire
1637 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1638 by the arguments in the first place. */
1640 = pending_stack_adjust
- adjustment
+ unadjusted_args_size
;
1645 /* Scan X expression if it does not dereference any argument slots
1646 we already clobbered by tail call arguments (as noted in stored_args_map
1648 Return nonzero if X expression dereferences such argument slots,
1652 check_sibcall_argument_overlap_1 (rtx x
)
1662 code
= GET_CODE (x
);
1666 if (XEXP (x
, 0) == current_function_internal_arg_pointer
)
1668 else if (GET_CODE (XEXP (x
, 0)) == PLUS
1669 && XEXP (XEXP (x
, 0), 0) ==
1670 current_function_internal_arg_pointer
1671 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
)
1672 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
1676 #ifdef ARGS_GROW_DOWNWARD
1677 i
= -i
- GET_MODE_SIZE (GET_MODE (x
));
1680 for (k
= 0; k
< GET_MODE_SIZE (GET_MODE (x
)); k
++)
1681 if (i
+ k
< stored_args_map
->n_bits
1682 && TEST_BIT (stored_args_map
, i
+ k
))
1688 /* Scan all subexpressions. */
1689 fmt
= GET_RTX_FORMAT (code
);
1690 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
1694 if (check_sibcall_argument_overlap_1 (XEXP (x
, i
)))
1697 else if (*fmt
== 'E')
1699 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
1700 if (check_sibcall_argument_overlap_1 (XVECEXP (x
, i
, j
)))
1707 /* Scan sequence after INSN if it does not dereference any argument slots
1708 we already clobbered by tail call arguments (as noted in stored_args_map
1709 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1710 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1711 should be 0). Return nonzero if sequence after INSN dereferences such argument
1712 slots, zero otherwise. */
1715 check_sibcall_argument_overlap (rtx insn
, struct arg_data
*arg
, int mark_stored_args_map
)
1719 if (insn
== NULL_RTX
)
1720 insn
= get_insns ();
1722 insn
= NEXT_INSN (insn
);
1724 for (; insn
; insn
= NEXT_INSN (insn
))
1726 && check_sibcall_argument_overlap_1 (PATTERN (insn
)))
1729 if (mark_stored_args_map
)
1731 #ifdef ARGS_GROW_DOWNWARD
1732 low
= -arg
->locate
.slot_offset
.constant
- arg
->locate
.size
.constant
;
1734 low
= arg
->locate
.slot_offset
.constant
;
1737 for (high
= low
+ arg
->locate
.size
.constant
; low
< high
; low
++)
1738 SET_BIT (stored_args_map
, low
);
1740 return insn
!= NULL_RTX
;
1744 fix_unsafe_tree (tree t
)
1746 switch (unsafe_for_reeval (t
))
1751 case 1: /* Mildly unsafe. */
1752 t
= unsave_expr (t
);
1755 case 2: /* Wildly unsafe. */
1757 tree var
= build_decl (VAR_DECL
, NULL_TREE
,
1760 expand_expr (t
, NULL_RTX
, VOIDmode
, EXPAND_NORMAL
));
1772 /* If function value *VALUE was returned at the most significant end of a
1773 register, shift it towards the least significant end and convert it to
1774 TYPE's mode. Return true and update *VALUE if some action was needed.
1776 TYPE is the type of the function's return value, which is known not
1777 to have mode BLKmode. */
1780 shift_returned_value (tree type
, rtx
*value
)
1782 if (targetm
.calls
.return_in_msb (type
))
1784 HOST_WIDE_INT shift
;
1786 shift
= (GET_MODE_BITSIZE (GET_MODE (*value
))
1787 - BITS_PER_UNIT
* int_size_in_bytes (type
));
1790 /* Shift the value into the low part of the register. */
1791 *value
= expand_binop (GET_MODE (*value
), lshr_optab
, *value
,
1792 GEN_INT (shift
), 0, 1, OPTAB_WIDEN
);
1794 /* Truncate it to the type's mode, or its integer equivalent.
1795 This is subject to TRULY_NOOP_TRUNCATION. */
1796 *value
= convert_to_mode (int_mode_for_mode (TYPE_MODE (type
)),
1799 /* Now convert it to the final form. */
1800 *value
= gen_lowpart (TYPE_MODE (type
), *value
);
1807 /* Remove all REG_EQUIV notes found in the insn chain. */
1810 purge_reg_equiv_notes (void)
1814 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1818 rtx note
= find_reg_note (insn
, REG_EQUIV
, 0);
1821 /* Remove the note and keep looking at the notes for
1823 remove_note (insn
, note
);
1831 /* Clear RTX_UNCHANGING_P flag of incoming argument MEMs. */
1834 purge_mem_unchanging_flag (rtx x
)
1843 code
= GET_CODE (x
);
1847 if (RTX_UNCHANGING_P (x
)
1848 && (XEXP (x
, 0) == current_function_internal_arg_pointer
1849 || (GET_CODE (XEXP (x
, 0)) == PLUS
1850 && XEXP (XEXP (x
, 0), 0) ==
1851 current_function_internal_arg_pointer
1852 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
)))
1853 RTX_UNCHANGING_P (x
) = 0;
1857 /* Scan all subexpressions. */
1858 fmt
= GET_RTX_FORMAT (code
);
1859 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
1862 purge_mem_unchanging_flag (XEXP (x
, i
));
1863 else if (*fmt
== 'E')
1864 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
1865 purge_mem_unchanging_flag (XVECEXP (x
, i
, j
));
1870 /* Generate all the code for a function call
1871 and return an rtx for its value.
1872 Store the value in TARGET (specified as an rtx) if convenient.
1873 If the value is stored in TARGET then TARGET is returned.
1874 If IGNORE is nonzero, then we ignore the value of the function call. */
1877 expand_call (tree exp
, rtx target
, int ignore
)
1879 /* Nonzero if we are currently expanding a call. */
1880 static int currently_expanding_call
= 0;
1882 /* List of actual parameters. */
1883 tree actparms
= TREE_OPERAND (exp
, 1);
1884 /* RTX for the function to be called. */
1886 /* Sequence of insns to perform a normal "call". */
1887 rtx normal_call_insns
= NULL_RTX
;
1888 /* Sequence of insns to perform a tail "call". */
1889 rtx tail_call_insns
= NULL_RTX
;
1890 /* Data type of the function. */
1892 tree type_arg_types
;
1893 /* Declaration of the function being called,
1894 or 0 if the function is computed (not known by name). */
1896 /* The type of the function being called. */
1898 bool try_tail_call
= CALL_EXPR_TAILCALL (exp
);
1901 /* Register in which non-BLKmode value will be returned,
1902 or 0 if no value or if value is BLKmode. */
1904 /* Address where we should return a BLKmode value;
1905 0 if value not BLKmode. */
1906 rtx structure_value_addr
= 0;
1907 /* Nonzero if that address is being passed by treating it as
1908 an extra, implicit first parameter. Otherwise,
1909 it is passed by being copied directly into struct_value_rtx. */
1910 int structure_value_addr_parm
= 0;
1911 /* Size of aggregate value wanted, or zero if none wanted
1912 or if we are using the non-reentrant PCC calling convention
1913 or expecting the value in registers. */
1914 HOST_WIDE_INT struct_value_size
= 0;
1915 /* Nonzero if called function returns an aggregate in memory PCC style,
1916 by returning the address of where to find it. */
1917 int pcc_struct_value
= 0;
1918 rtx struct_value
= 0;
1920 /* Number of actual parameters in this call, including struct value addr. */
1922 /* Number of named args. Args after this are anonymous ones
1923 and they must all go on the stack. */
1926 /* Vector of information about each argument.
1927 Arguments are numbered in the order they will be pushed,
1928 not the order they are written. */
1929 struct arg_data
*args
;
1931 /* Total size in bytes of all the stack-parms scanned so far. */
1932 struct args_size args_size
;
1933 struct args_size adjusted_args_size
;
1934 /* Size of arguments before any adjustments (such as rounding). */
1935 int unadjusted_args_size
;
1936 /* Data on reg parms scanned so far. */
1937 CUMULATIVE_ARGS args_so_far
;
1938 /* Nonzero if a reg parm has been scanned. */
1940 /* Nonzero if this is an indirect function call. */
1942 /* Nonzero if we must avoid push-insns in the args for this call.
1943 If stack space is allocated for register parameters, but not by the
1944 caller, then it is preallocated in the fixed part of the stack frame.
1945 So the entire argument block must then be preallocated (i.e., we
1946 ignore PUSH_ROUNDING in that case). */
1948 int must_preallocate
= !PUSH_ARGS
;
1950 /* Size of the stack reserved for parameter registers. */
1951 int reg_parm_stack_space
= 0;
1953 /* Address of space preallocated for stack parms
1954 (on machines that lack push insns), or 0 if space not preallocated. */
1957 /* Mask of ECF_ flags. */
1959 #ifdef REG_PARM_STACK_SPACE
1960 /* Define the boundary of the register parm stack space that needs to be
1962 int low_to_save
, high_to_save
;
1963 rtx save_area
= 0; /* Place that it is saved */
1966 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
1967 char *initial_stack_usage_map
= stack_usage_map
;
1969 int old_stack_allocated
;
1971 /* State variables to track stack modifications. */
1972 rtx old_stack_level
= 0;
1973 int old_stack_arg_under_construction
= 0;
1974 int old_pending_adj
= 0;
1975 int old_inhibit_defer_pop
= inhibit_defer_pop
;
1977 /* Some stack pointer alterations we make are performed via
1978 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
1979 which we then also need to save/restore along the way. */
1980 int old_stack_pointer_delta
= 0;
1983 tree p
= TREE_OPERAND (exp
, 0);
1984 tree addr
= TREE_OPERAND (exp
, 0);
1986 /* The alignment of the stack, in bits. */
1987 HOST_WIDE_INT preferred_stack_boundary
;
1988 /* The alignment of the stack, in bytes. */
1989 HOST_WIDE_INT preferred_unit_stack_boundary
;
1990 /* The static chain value to use for this call. */
1991 rtx static_chain_value
;
1992 /* See if this is "nothrow" function call. */
1993 if (TREE_NOTHROW (exp
))
1994 flags
|= ECF_NOTHROW
;
1996 /* See if we can find a DECL-node for the actual function, and get the
1997 function attributes (flags) from the function decl or type node. */
1998 fndecl
= get_callee_fndecl (exp
);
2001 fntype
= TREE_TYPE (fndecl
);
2002 flags
|= flags_from_decl_or_type (fndecl
);
2006 fntype
= TREE_TYPE (TREE_TYPE (p
));
2007 flags
|= flags_from_decl_or_type (fntype
);
2010 struct_value
= targetm
.calls
.struct_value_rtx (fntype
, 0);
2012 /* Warn if this value is an aggregate type,
2013 regardless of which calling convention we are using for it. */
2014 if (warn_aggregate_return
&& AGGREGATE_TYPE_P (TREE_TYPE (exp
)))
2015 warning ("function call has aggregate value");
2017 /* If the result of a pure or const function call is ignored (or void),
2018 and none of its arguments are volatile, we can avoid expanding the
2019 call and just evaluate the arguments for side-effects. */
2020 if ((flags
& (ECF_CONST
| ECF_PURE
))
2021 && (ignore
|| target
== const0_rtx
2022 || TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
))
2024 bool volatilep
= false;
2027 for (arg
= actparms
; arg
; arg
= TREE_CHAIN (arg
))
2028 if (TREE_THIS_VOLATILE (TREE_VALUE (arg
)))
2036 for (arg
= actparms
; arg
; arg
= TREE_CHAIN (arg
))
2037 expand_expr (TREE_VALUE (arg
), const0_rtx
,
2038 VOIDmode
, EXPAND_NORMAL
);
2043 #ifdef REG_PARM_STACK_SPACE
2044 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
2047 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2048 if (reg_parm_stack_space
> 0 && PUSH_ARGS
)
2049 must_preallocate
= 1;
2052 /* Set up a place to return a structure. */
2054 /* Cater to broken compilers. */
2055 if (aggregate_value_p (exp
, fndecl
))
2057 /* This call returns a big structure. */
2058 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
2060 #ifdef PCC_STATIC_STRUCT_RETURN
2062 pcc_struct_value
= 1;
2064 #else /* not PCC_STATIC_STRUCT_RETURN */
2066 struct_value_size
= int_size_in_bytes (TREE_TYPE (exp
));
2068 if (CALL_EXPR_HAS_RETURN_SLOT_ADDR (exp
))
2070 /* The structure value address arg is already in actparms.
2071 Pull it out. It might be nice to just leave it there, but
2072 we need to set structure_value_addr. */
2073 tree return_arg
= TREE_VALUE (actparms
);
2074 actparms
= TREE_CHAIN (actparms
);
2075 structure_value_addr
= expand_expr (return_arg
, NULL_RTX
,
2076 VOIDmode
, EXPAND_NORMAL
);
2078 else if (target
&& MEM_P (target
))
2079 structure_value_addr
= XEXP (target
, 0);
2082 /* For variable-sized objects, we must be called with a target
2083 specified. If we were to allocate space on the stack here,
2084 we would have no way of knowing when to free it. */
2085 rtx d
= assign_temp (TREE_TYPE (exp
), 1, 1, 1);
2087 mark_temp_addr_taken (d
);
2088 structure_value_addr
= XEXP (d
, 0);
2092 #endif /* not PCC_STATIC_STRUCT_RETURN */
2095 /* Figure out the amount to which the stack should be aligned. */
2096 preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
2099 struct cgraph_rtl_info
*i
= cgraph_rtl_info (fndecl
);
2100 if (i
&& i
->preferred_incoming_stack_boundary
)
2101 preferred_stack_boundary
= i
->preferred_incoming_stack_boundary
;
2104 /* Operand 0 is a pointer-to-function; get the type of the function. */
2105 funtype
= TREE_TYPE (addr
);
2106 if (! POINTER_TYPE_P (funtype
))
2108 funtype
= TREE_TYPE (funtype
);
2110 /* Munge the tree to split complex arguments into their imaginary
2112 if (targetm
.calls
.split_complex_arg
)
2114 type_arg_types
= split_complex_types (TYPE_ARG_TYPES (funtype
));
2115 actparms
= split_complex_values (actparms
);
2118 type_arg_types
= TYPE_ARG_TYPES (funtype
);
2120 if (flags
& ECF_MAY_BE_ALLOCA
)
2121 current_function_calls_alloca
= 1;
2123 /* If struct_value_rtx is 0, it means pass the address
2124 as if it were an extra parameter. */
2125 if (structure_value_addr
&& struct_value
== 0)
2127 /* If structure_value_addr is a REG other than
2128 virtual_outgoing_args_rtx, we can use always use it. If it
2129 is not a REG, we must always copy it into a register.
2130 If it is virtual_outgoing_args_rtx, we must copy it to another
2131 register in some cases. */
2132 rtx temp
= (!REG_P (structure_value_addr
)
2133 || (ACCUMULATE_OUTGOING_ARGS
2134 && stack_arg_under_construction
2135 && structure_value_addr
== virtual_outgoing_args_rtx
)
2136 ? copy_addr_to_reg (convert_memory_address
2137 (Pmode
, structure_value_addr
))
2138 : structure_value_addr
);
2141 = tree_cons (error_mark_node
,
2142 make_tree (build_pointer_type (TREE_TYPE (funtype
)),
2145 structure_value_addr_parm
= 1;
2148 /* Count the arguments and set NUM_ACTUALS. */
2149 for (p
= actparms
, num_actuals
= 0; p
; p
= TREE_CHAIN (p
))
2152 /* Compute number of named args.
2153 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2155 if (type_arg_types
!= 0)
2157 = (list_length (type_arg_types
)
2158 /* Count the struct value address, if it is passed as a parm. */
2159 + structure_value_addr_parm
);
2161 /* If we know nothing, treat all args as named. */
2162 n_named_args
= num_actuals
;
2164 /* Start updating where the next arg would go.
2166 On some machines (such as the PA) indirect calls have a different
2167 calling convention than normal calls. The fourth argument in
2168 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2170 INIT_CUMULATIVE_ARGS (args_so_far
, funtype
, NULL_RTX
, fndecl
, n_named_args
);
2172 /* Now possibly adjust the number of named args.
2173 Normally, don't include the last named arg if anonymous args follow.
2174 We do include the last named arg if
2175 targetm.calls.strict_argument_naming() returns nonzero.
2176 (If no anonymous args follow, the result of list_length is actually
2177 one too large. This is harmless.)
2179 If targetm.calls.pretend_outgoing_varargs_named() returns
2180 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2181 this machine will be able to place unnamed args that were passed
2182 in registers into the stack. So treat all args as named. This
2183 allows the insns emitting for a specific argument list to be
2184 independent of the function declaration.
2186 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2187 we do not have any reliable way to pass unnamed args in
2188 registers, so we must force them into memory. */
2190 if (type_arg_types
!= 0
2191 && targetm
.calls
.strict_argument_naming (&args_so_far
))
2193 else if (type_arg_types
!= 0
2194 && ! targetm
.calls
.pretend_outgoing_varargs_named (&args_so_far
))
2195 /* Don't include the last named arg. */
2198 /* Treat all args as named. */
2199 n_named_args
= num_actuals
;
2201 /* Make a vector to hold all the information about each arg. */
2202 args
= alloca (num_actuals
* sizeof (struct arg_data
));
2203 memset (args
, 0, num_actuals
* sizeof (struct arg_data
));
2205 /* Build up entries in the ARGS array, compute the size of the
2206 arguments into ARGS_SIZE, etc. */
2207 initialize_argument_information (num_actuals
, args
, &args_size
,
2208 n_named_args
, actparms
, fndecl
,
2209 &args_so_far
, reg_parm_stack_space
,
2210 &old_stack_level
, &old_pending_adj
,
2211 &must_preallocate
, &flags
,
2212 &try_tail_call
, CALL_FROM_THUNK_P (exp
));
2216 /* If this function requires a variable-sized argument list, don't
2217 try to make a cse'able block for this call. We may be able to
2218 do this eventually, but it is too complicated to keep track of
2219 what insns go in the cse'able block and which don't. */
2221 flags
&= ~ECF_LIBCALL_BLOCK
;
2222 must_preallocate
= 1;
2225 /* Now make final decision about preallocating stack space. */
2226 must_preallocate
= finalize_must_preallocate (must_preallocate
,
2230 /* If the structure value address will reference the stack pointer, we
2231 must stabilize it. We don't need to do this if we know that we are
2232 not going to adjust the stack pointer in processing this call. */
2234 if (structure_value_addr
2235 && (reg_mentioned_p (virtual_stack_dynamic_rtx
, structure_value_addr
)
2236 || reg_mentioned_p (virtual_outgoing_args_rtx
,
2237 structure_value_addr
))
2239 || (!ACCUMULATE_OUTGOING_ARGS
&& args_size
.constant
)))
2240 structure_value_addr
= copy_to_reg (structure_value_addr
);
2242 /* Tail calls can make things harder to debug, and we're traditionally
2243 pushed these optimizations into -O2. Don't try if we're already
2244 expanding a call, as that means we're an argument. Don't try if
2245 there's cleanups, as we know there's code to follow the call.
2247 If rtx_equal_function_value_matters is false, that means we've
2248 finished with regular parsing. Which means that some of the
2249 machinery we use to generate tail-calls is no longer in place.
2250 This is most often true of sjlj-exceptions, which we couldn't
2251 tail-call to anyway.
2253 If current_nesting_level () == 0, we're being called after
2254 the function body has been expanded. This can happen when
2255 setting up trampolines in expand_function_end. */
2256 if (currently_expanding_call
++ != 0
2257 || !flag_optimize_sibling_calls
2258 || !rtx_equal_function_value_matters
2259 || current_nesting_level () == 0
2261 || lookup_stmt_eh_region (exp
) >= 0)
2264 /* Rest of purposes for tail call optimizations to fail. */
2266 #ifdef HAVE_sibcall_epilogue
2267 !HAVE_sibcall_epilogue
2272 /* Doing sibling call optimization needs some work, since
2273 structure_value_addr can be allocated on the stack.
2274 It does not seem worth the effort since few optimizable
2275 sibling calls will return a structure. */
2276 || structure_value_addr
!= NULL_RTX
2277 /* Check whether the target is able to optimize the call
2279 || !targetm
.function_ok_for_sibcall (fndecl
, exp
)
2280 /* Functions that do not return exactly once may not be sibcall
2282 || (flags
& (ECF_RETURNS_TWICE
| ECF_LONGJMP
| ECF_NORETURN
))
2283 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr
)))
2284 /* If the called function is nested in the current one, it might access
2285 some of the caller's arguments, but could clobber them beforehand if
2286 the argument areas are shared. */
2287 || (fndecl
&& decl_function_context (fndecl
) == current_function_decl
)
2288 /* If this function requires more stack slots than the current
2289 function, we cannot change it into a sibling call. */
2290 || args_size
.constant
> current_function_args_size
2291 /* If the callee pops its own arguments, then it must pop exactly
2292 the same number of arguments as the current function. */
2293 || (RETURN_POPS_ARGS (fndecl
, funtype
, args_size
.constant
)
2294 != RETURN_POPS_ARGS (current_function_decl
,
2295 TREE_TYPE (current_function_decl
),
2296 current_function_args_size
))
2297 || !lang_hooks
.decls
.ok_for_sibcall (fndecl
))
2303 actparms
= NULL_TREE
;
2304 /* Ok, we're going to give the tail call the old college try.
2305 This means we're going to evaluate the function arguments
2306 up to three times. There are two degrees of badness we can
2307 encounter, those that can be unsaved and those that can't.
2308 (See unsafe_for_reeval commentary for details.)
2310 Generate a new argument list. Pass safe arguments through
2311 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2312 For hard badness, evaluate them now and put their resulting
2313 rtx in a temporary VAR_DECL.
2315 initialize_argument_information has ordered the array for the
2316 order to be pushed, and we must remember this when reconstructing
2317 the original argument order. */
2319 if (PUSH_ARGS_REVERSED
)
2328 i
= num_actuals
- 1;
2332 for (; i
!= end
; i
+= inc
)
2334 args
[i
].tree_value
= fix_unsafe_tree (args
[i
].tree_value
);
2336 /* Do the same for the function address if it is an expression. */
2338 addr
= fix_unsafe_tree (addr
);
2342 /* Ensure current function's preferred stack boundary is at least
2343 what we need. We don't have to increase alignment for recursive
2345 if (cfun
->preferred_stack_boundary
< preferred_stack_boundary
2346 && fndecl
!= current_function_decl
)
2347 cfun
->preferred_stack_boundary
= preferred_stack_boundary
;
2348 if (fndecl
== current_function_decl
)
2349 cfun
->recursive_call_emit
= true;
2351 preferred_unit_stack_boundary
= preferred_stack_boundary
/ BITS_PER_UNIT
;
2353 /* We want to make two insn chains; one for a sibling call, the other
2354 for a normal call. We will select one of the two chains after
2355 initial RTL generation is complete. */
2356 for (pass
= try_tail_call
? 0 : 1; pass
< 2; pass
++)
2358 int sibcall_failure
= 0;
2359 /* We want to emit any pending stack adjustments before the tail
2360 recursion "call". That way we know any adjustment after the tail
2361 recursion call can be ignored if we indeed use the tail
2363 int save_pending_stack_adjust
= 0;
2364 int save_stack_pointer_delta
= 0;
2366 rtx before_call
, next_arg_reg
;
2370 /* Emit any queued insns now; otherwise they would end up in
2371 only one of the alternates. */
2374 /* State variables we need to save and restore between
2376 save_pending_stack_adjust
= pending_stack_adjust
;
2377 save_stack_pointer_delta
= stack_pointer_delta
;
2380 flags
&= ~ECF_SIBCALL
;
2382 flags
|= ECF_SIBCALL
;
2384 /* Other state variables that we must reinitialize each time
2385 through the loop (that are not initialized by the loop itself). */
2389 /* Start a new sequence for the normal call case.
2391 From this point on, if the sibling call fails, we want to set
2392 sibcall_failure instead of continuing the loop. */
2397 /* We know at this point that there are not currently any
2398 pending cleanups. If, however, in the process of evaluating
2399 the arguments we were to create some, we'll need to be
2400 able to get rid of them. */
2401 expand_start_target_temps ();
2404 /* Don't let pending stack adjusts add up to too much.
2405 Also, do all pending adjustments now if there is any chance
2406 this might be a call to alloca or if we are expanding a sibling
2407 call sequence or if we are calling a function that is to return
2408 with stack pointer depressed. */
2409 if (pending_stack_adjust
>= 32
2410 || (pending_stack_adjust
> 0
2411 && (flags
& (ECF_MAY_BE_ALLOCA
| ECF_SP_DEPRESSED
)))
2413 do_pending_stack_adjust ();
2415 /* When calling a const function, we must pop the stack args right away,
2416 so that the pop is deleted or moved with the call. */
2417 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
2420 /* Precompute any arguments as needed. */
2422 precompute_arguments (flags
, num_actuals
, args
);
2424 /* Now we are about to start emitting insns that can be deleted
2425 if a libcall is deleted. */
2426 if (pass
&& (flags
& (ECF_LIBCALL_BLOCK
| ECF_MALLOC
)))
2429 adjusted_args_size
= args_size
;
2430 /* Compute the actual size of the argument block required. The variable
2431 and constant sizes must be combined, the size may have to be rounded,
2432 and there may be a minimum required size. When generating a sibcall
2433 pattern, do not round up, since we'll be re-using whatever space our
2435 unadjusted_args_size
2436 = compute_argument_block_size (reg_parm_stack_space
,
2437 &adjusted_args_size
,
2439 : preferred_stack_boundary
));
2441 old_stack_allocated
= stack_pointer_delta
- pending_stack_adjust
;
2443 /* The argument block when performing a sibling call is the
2444 incoming argument block. */
2447 argblock
= virtual_incoming_args_rtx
;
2449 #ifdef STACK_GROWS_DOWNWARD
2450 = plus_constant (argblock
, current_function_pretend_args_size
);
2452 = plus_constant (argblock
, -current_function_pretend_args_size
);
2454 stored_args_map
= sbitmap_alloc (args_size
.constant
);
2455 sbitmap_zero (stored_args_map
);
2458 /* If we have no actual push instructions, or shouldn't use them,
2459 make space for all args right now. */
2460 else if (adjusted_args_size
.var
!= 0)
2462 if (old_stack_level
== 0)
2464 emit_stack_save (SAVE_BLOCK
, &old_stack_level
, NULL_RTX
);
2465 old_stack_pointer_delta
= stack_pointer_delta
;
2466 old_pending_adj
= pending_stack_adjust
;
2467 pending_stack_adjust
= 0;
2468 /* stack_arg_under_construction says whether a stack arg is
2469 being constructed at the old stack level. Pushing the stack
2470 gets a clean outgoing argument block. */
2471 old_stack_arg_under_construction
= stack_arg_under_construction
;
2472 stack_arg_under_construction
= 0;
2474 argblock
= push_block (ARGS_SIZE_RTX (adjusted_args_size
), 0, 0);
2478 /* Note that we must go through the motions of allocating an argument
2479 block even if the size is zero because we may be storing args
2480 in the area reserved for register arguments, which may be part of
2483 int needed
= adjusted_args_size
.constant
;
2485 /* Store the maximum argument space used. It will be pushed by
2486 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2489 if (needed
> current_function_outgoing_args_size
)
2490 current_function_outgoing_args_size
= needed
;
2492 if (must_preallocate
)
2494 if (ACCUMULATE_OUTGOING_ARGS
)
2496 /* Since the stack pointer will never be pushed, it is
2497 possible for the evaluation of a parm to clobber
2498 something we have already written to the stack.
2499 Since most function calls on RISC machines do not use
2500 the stack, this is uncommon, but must work correctly.
2502 Therefore, we save any area of the stack that was already
2503 written and that we are using. Here we set up to do this
2504 by making a new stack usage map from the old one. The
2505 actual save will be done by store_one_arg.
2507 Another approach might be to try to reorder the argument
2508 evaluations to avoid this conflicting stack usage. */
2510 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2511 /* Since we will be writing into the entire argument area,
2512 the map must be allocated for its entire size, not just
2513 the part that is the responsibility of the caller. */
2514 needed
+= reg_parm_stack_space
;
2517 #ifdef ARGS_GROW_DOWNWARD
2518 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2521 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
2524 stack_usage_map
= alloca (highest_outgoing_arg_in_use
);
2526 if (initial_highest_arg_in_use
)
2527 memcpy (stack_usage_map
, initial_stack_usage_map
,
2528 initial_highest_arg_in_use
);
2530 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
2531 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
2532 (highest_outgoing_arg_in_use
2533 - initial_highest_arg_in_use
));
2536 /* The address of the outgoing argument list must not be
2537 copied to a register here, because argblock would be left
2538 pointing to the wrong place after the call to
2539 allocate_dynamic_stack_space below. */
2541 argblock
= virtual_outgoing_args_rtx
;
2545 if (inhibit_defer_pop
== 0)
2547 /* Try to reuse some or all of the pending_stack_adjust
2548 to get this space. */
2550 = (combine_pending_stack_adjustment_and_call
2551 (unadjusted_args_size
,
2552 &adjusted_args_size
,
2553 preferred_unit_stack_boundary
));
2555 /* combine_pending_stack_adjustment_and_call computes
2556 an adjustment before the arguments are allocated.
2557 Account for them and see whether or not the stack
2558 needs to go up or down. */
2559 needed
= unadjusted_args_size
- needed
;
2563 /* We're releasing stack space. */
2564 /* ??? We can avoid any adjustment at all if we're
2565 already aligned. FIXME. */
2566 pending_stack_adjust
= -needed
;
2567 do_pending_stack_adjust ();
2571 /* We need to allocate space. We'll do that in
2572 push_block below. */
2573 pending_stack_adjust
= 0;
2576 /* Special case this because overhead of `push_block' in
2577 this case is non-trivial. */
2579 argblock
= virtual_outgoing_args_rtx
;
2582 argblock
= push_block (GEN_INT (needed
), 0, 0);
2583 #ifdef ARGS_GROW_DOWNWARD
2584 argblock
= plus_constant (argblock
, needed
);
2588 /* We only really need to call `copy_to_reg' in the case
2589 where push insns are going to be used to pass ARGBLOCK
2590 to a function call in ARGS. In that case, the stack
2591 pointer changes value from the allocation point to the
2592 call point, and hence the value of
2593 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2594 as well always do it. */
2595 argblock
= copy_to_reg (argblock
);
2600 if (ACCUMULATE_OUTGOING_ARGS
)
2602 /* The save/restore code in store_one_arg handles all
2603 cases except one: a constructor call (including a C
2604 function returning a BLKmode struct) to initialize
2606 if (stack_arg_under_construction
)
2608 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2609 rtx push_size
= GEN_INT (reg_parm_stack_space
2610 + adjusted_args_size
.constant
);
2612 rtx push_size
= GEN_INT (adjusted_args_size
.constant
);
2614 if (old_stack_level
== 0)
2616 emit_stack_save (SAVE_BLOCK
, &old_stack_level
,
2618 old_stack_pointer_delta
= stack_pointer_delta
;
2619 old_pending_adj
= pending_stack_adjust
;
2620 pending_stack_adjust
= 0;
2621 /* stack_arg_under_construction says whether a stack
2622 arg is being constructed at the old stack level.
2623 Pushing the stack gets a clean outgoing argument
2625 old_stack_arg_under_construction
2626 = stack_arg_under_construction
;
2627 stack_arg_under_construction
= 0;
2628 /* Make a new map for the new argument list. */
2629 stack_usage_map
= alloca (highest_outgoing_arg_in_use
);
2630 memset (stack_usage_map
, 0, highest_outgoing_arg_in_use
);
2631 highest_outgoing_arg_in_use
= 0;
2633 allocate_dynamic_stack_space (push_size
, NULL_RTX
,
2637 /* If argument evaluation might modify the stack pointer,
2638 copy the address of the argument list to a register. */
2639 for (i
= 0; i
< num_actuals
; i
++)
2640 if (args
[i
].pass_on_stack
)
2642 argblock
= copy_addr_to_reg (argblock
);
2647 compute_argument_addresses (args
, argblock
, num_actuals
);
2649 /* If we push args individually in reverse order, perform stack alignment
2650 before the first push (the last arg). */
2651 if (PUSH_ARGS_REVERSED
&& argblock
== 0
2652 && adjusted_args_size
.constant
!= unadjusted_args_size
)
2654 /* When the stack adjustment is pending, we get better code
2655 by combining the adjustments. */
2656 if (pending_stack_adjust
2657 && ! (flags
& ECF_LIBCALL_BLOCK
)
2658 && ! inhibit_defer_pop
)
2660 pending_stack_adjust
2661 = (combine_pending_stack_adjustment_and_call
2662 (unadjusted_args_size
,
2663 &adjusted_args_size
,
2664 preferred_unit_stack_boundary
));
2665 do_pending_stack_adjust ();
2667 else if (argblock
== 0)
2668 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2669 - unadjusted_args_size
));
2671 /* Now that the stack is properly aligned, pops can't safely
2672 be deferred during the evaluation of the arguments. */
2675 funexp
= rtx_for_function_call (fndecl
, addr
);
2677 /* Figure out the register where the value, if any, will come back. */
2679 if (TYPE_MODE (TREE_TYPE (exp
)) != VOIDmode
2680 && ! structure_value_addr
)
2682 if (pcc_struct_value
)
2683 valreg
= hard_function_value (build_pointer_type (TREE_TYPE (exp
)),
2684 fndecl
, (pass
== 0));
2686 valreg
= hard_function_value (TREE_TYPE (exp
), fndecl
, (pass
== 0));
2689 /* Precompute all register parameters. It isn't safe to compute anything
2690 once we have started filling any specific hard regs. */
2691 precompute_register_parameters (num_actuals
, args
, ®_parm_seen
);
2693 if (TREE_OPERAND (exp
, 2))
2694 static_chain_value
= expand_expr (TREE_OPERAND (exp
, 2),
2695 NULL_RTX
, VOIDmode
, 0);
2697 static_chain_value
= 0;
2699 #ifdef REG_PARM_STACK_SPACE
2700 /* Save the fixed argument area if it's part of the caller's frame and
2701 is clobbered by argument setup for this call. */
2702 if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
2703 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
2704 &low_to_save
, &high_to_save
);
2707 /* Now store (and compute if necessary) all non-register parms.
2708 These come before register parms, since they can require block-moves,
2709 which could clobber the registers used for register parms.
2710 Parms which have partial registers are not stored here,
2711 but we do preallocate space here if they want that. */
2713 for (i
= 0; i
< num_actuals
; i
++)
2714 if (args
[i
].reg
== 0 || args
[i
].pass_on_stack
)
2716 rtx before_arg
= get_last_insn ();
2718 if (store_one_arg (&args
[i
], argblock
, flags
,
2719 adjusted_args_size
.var
!= 0,
2720 reg_parm_stack_space
)
2722 && check_sibcall_argument_overlap (before_arg
,
2724 sibcall_failure
= 1;
2726 if (flags
& ECF_CONST
2728 && args
[i
].value
== args
[i
].stack
)
2729 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
2730 gen_rtx_USE (VOIDmode
,
2735 /* If we have a parm that is passed in registers but not in memory
2736 and whose alignment does not permit a direct copy into registers,
2737 make a group of pseudos that correspond to each register that we
2739 if (STRICT_ALIGNMENT
)
2740 store_unaligned_arguments_into_pseudos (args
, num_actuals
);
2742 /* Now store any partially-in-registers parm.
2743 This is the last place a block-move can happen. */
2745 for (i
= 0; i
< num_actuals
; i
++)
2746 if (args
[i
].partial
!= 0 && ! args
[i
].pass_on_stack
)
2748 rtx before_arg
= get_last_insn ();
2750 if (store_one_arg (&args
[i
], argblock
, flags
,
2751 adjusted_args_size
.var
!= 0,
2752 reg_parm_stack_space
)
2754 && check_sibcall_argument_overlap (before_arg
,
2756 sibcall_failure
= 1;
2759 /* If we pushed args in forward order, perform stack alignment
2760 after pushing the last arg. */
2761 if (!PUSH_ARGS_REVERSED
&& argblock
== 0)
2762 anti_adjust_stack (GEN_INT (adjusted_args_size
.constant
2763 - unadjusted_args_size
));
2765 /* If register arguments require space on the stack and stack space
2766 was not preallocated, allocate stack space here for arguments
2767 passed in registers. */
2768 #ifdef OUTGOING_REG_PARM_STACK_SPACE
2769 if (!ACCUMULATE_OUTGOING_ARGS
2770 && must_preallocate
== 0 && reg_parm_stack_space
> 0)
2771 anti_adjust_stack (GEN_INT (reg_parm_stack_space
));
2774 /* Pass the function the address in which to return a
2776 if (pass
!= 0 && structure_value_addr
&& ! structure_value_addr_parm
)
2778 structure_value_addr
2779 = convert_memory_address (Pmode
, structure_value_addr
);
2780 emit_move_insn (struct_value
,
2782 force_operand (structure_value_addr
,
2785 if (REG_P (struct_value
))
2786 use_reg (&call_fusage
, struct_value
);
2789 funexp
= prepare_call_address (funexp
, static_chain_value
,
2790 &call_fusage
, reg_parm_seen
, pass
== 0);
2792 load_register_parameters (args
, num_actuals
, &call_fusage
, flags
,
2793 pass
== 0, &sibcall_failure
);
2795 /* Perform postincrements before actually calling the function. */
2798 /* Save a pointer to the last insn before the call, so that we can
2799 later safely search backwards to find the CALL_INSN. */
2800 before_call
= get_last_insn ();
2802 /* Set up next argument register. For sibling calls on machines
2803 with register windows this should be the incoming register. */
2804 #ifdef FUNCTION_INCOMING_ARG
2806 next_arg_reg
= FUNCTION_INCOMING_ARG (args_so_far
, VOIDmode
,
2810 next_arg_reg
= FUNCTION_ARG (args_so_far
, VOIDmode
,
2813 /* All arguments and registers used for the call must be set up by
2816 /* Stack must be properly aligned now. */
2817 if (pass
&& stack_pointer_delta
% preferred_unit_stack_boundary
)
2820 /* Generate the actual call instruction. */
2821 emit_call_1 (funexp
, exp
, fndecl
, funtype
, unadjusted_args_size
,
2822 adjusted_args_size
.constant
, struct_value_size
,
2823 next_arg_reg
, valreg
, old_inhibit_defer_pop
, call_fusage
,
2824 flags
, & args_so_far
);
2826 /* If call is cse'able, make appropriate pair of reg-notes around it.
2827 Test valreg so we don't crash; may safely ignore `const'
2828 if return type is void. Disable for PARALLEL return values, because
2829 we have no way to move such values into a pseudo register. */
2830 if (pass
&& (flags
& ECF_LIBCALL_BLOCK
))
2834 bool failed
= valreg
== 0 || GET_CODE (valreg
) == PARALLEL
;
2836 insns
= get_insns ();
2838 /* Expansion of block moves possibly introduced a loop that may
2839 not appear inside libcall block. */
2840 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
2852 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2854 /* Mark the return value as a pointer if needed. */
2855 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
2856 mark_reg_pointer (temp
,
2857 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp
))));
2860 if (flag_unsafe_math_optimizations
2862 && DECL_BUILT_IN (fndecl
)
2863 && (DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRT
2864 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRTF
2865 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_SQRTL
))
2866 note
= gen_rtx_fmt_e (SQRT
,
2868 args
[0].initial_value
);
2871 /* Construct an "equal form" for the value which
2872 mentions all the arguments in order as well as
2873 the function name. */
2874 for (i
= 0; i
< num_actuals
; i
++)
2875 note
= gen_rtx_EXPR_LIST (VOIDmode
,
2876 args
[i
].initial_value
, note
);
2877 note
= gen_rtx_EXPR_LIST (VOIDmode
, funexp
, note
);
2879 if (flags
& ECF_PURE
)
2880 note
= gen_rtx_EXPR_LIST (VOIDmode
,
2881 gen_rtx_USE (VOIDmode
,
2882 gen_rtx_MEM (BLKmode
,
2883 gen_rtx_SCRATCH (VOIDmode
))),
2886 emit_libcall_block (insns
, temp
, valreg
, note
);
2891 else if (pass
&& (flags
& ECF_MALLOC
))
2893 rtx temp
= gen_reg_rtx (GET_MODE (valreg
));
2896 /* The return value from a malloc-like function is a pointer. */
2897 if (TREE_CODE (TREE_TYPE (exp
)) == POINTER_TYPE
)
2898 mark_reg_pointer (temp
, BIGGEST_ALIGNMENT
);
2900 emit_move_insn (temp
, valreg
);
2902 /* The return value from a malloc-like function can not alias
2904 last
= get_last_insn ();
2906 gen_rtx_EXPR_LIST (REG_NOALIAS
, temp
, REG_NOTES (last
));
2908 /* Write out the sequence. */
2909 insns
= get_insns ();
2915 /* For calls to `setjmp', etc., inform flow.c it should complain
2916 if nonvolatile values are live. For functions that cannot return,
2917 inform flow that control does not fall through. */
2919 if ((flags
& (ECF_NORETURN
| ECF_LONGJMP
)) || pass
== 0)
2921 /* The barrier must be emitted
2922 immediately after the CALL_INSN. Some ports emit more
2923 than just a CALL_INSN above, so we must search for it here. */
2925 rtx last
= get_last_insn ();
2926 while (!CALL_P (last
))
2928 last
= PREV_INSN (last
);
2929 /* There was no CALL_INSN? */
2930 if (last
== before_call
)
2934 emit_barrier_after (last
);
2936 /* Stack adjustments after a noreturn call are dead code.
2937 However when NO_DEFER_POP is in effect, we must preserve
2938 stack_pointer_delta. */
2939 if (inhibit_defer_pop
== 0)
2941 stack_pointer_delta
= old_stack_allocated
;
2942 pending_stack_adjust
= 0;
2946 if (flags
& ECF_LONGJMP
)
2947 current_function_calls_longjmp
= 1;
2949 /* If value type not void, return an rtx for the value. */
2951 if (TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
2953 target
= const0_rtx
;
2954 else if (structure_value_addr
)
2956 if (target
== 0 || !MEM_P (target
))
2959 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
2960 memory_address (TYPE_MODE (TREE_TYPE (exp
)),
2961 structure_value_addr
));
2962 set_mem_attributes (target
, exp
, 1);
2965 else if (pcc_struct_value
)
2967 /* This is the special C++ case where we need to
2968 know what the true target was. We take care to
2969 never use this value more than once in one expression. */
2970 target
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp
)),
2971 copy_to_reg (valreg
));
2972 set_mem_attributes (target
, exp
, 1);
2974 /* Handle calls that return values in multiple non-contiguous locations.
2975 The Irix 6 ABI has examples of this. */
2976 else if (GET_CODE (valreg
) == PARALLEL
)
2980 /* This will only be assigned once, so it can be readonly. */
2981 tree nt
= build_qualified_type (TREE_TYPE (exp
),
2982 (TYPE_QUALS (TREE_TYPE (exp
))
2983 | TYPE_QUAL_CONST
));
2985 target
= assign_temp (nt
, 0, 1, 1);
2986 preserve_temp_slots (target
);
2989 if (! rtx_equal_p (target
, valreg
))
2990 emit_group_store (target
, valreg
, TREE_TYPE (exp
),
2991 int_size_in_bytes (TREE_TYPE (exp
)));
2993 /* We can not support sibling calls for this case. */
2994 sibcall_failure
= 1;
2997 && GET_MODE (target
) == TYPE_MODE (TREE_TYPE (exp
))
2998 && GET_MODE (target
) == GET_MODE (valreg
))
3000 /* TARGET and VALREG cannot be equal at this point because the
3001 latter would not have REG_FUNCTION_VALUE_P true, while the
3002 former would if it were referring to the same register.
3004 If they refer to the same register, this move will be a no-op,
3005 except when function inlining is being done. */
3006 emit_move_insn (target
, valreg
);
3008 /* If we are setting a MEM, this code must be executed. Since it is
3009 emitted after the call insn, sibcall optimization cannot be
3010 performed in that case. */
3012 sibcall_failure
= 1;
3014 else if (TYPE_MODE (TREE_TYPE (exp
)) == BLKmode
)
3016 target
= copy_blkmode_from_reg (target
, valreg
, TREE_TYPE (exp
));
3018 /* We can not support sibling calls for this case. */
3019 sibcall_failure
= 1;
3023 if (shift_returned_value (TREE_TYPE (exp
), &valreg
))
3024 sibcall_failure
= 1;
3026 target
= copy_to_reg (valreg
);
3029 if (targetm
.calls
.promote_function_return(funtype
))
3031 /* If we promoted this return value, make the proper SUBREG. TARGET
3032 might be const0_rtx here, so be careful. */
3034 && TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
3035 && GET_MODE (target
) != TYPE_MODE (TREE_TYPE (exp
)))
3037 tree type
= TREE_TYPE (exp
);
3038 int unsignedp
= TYPE_UNSIGNED (type
);
3041 /* If we don't promote as expected, something is wrong. */
3042 if (GET_MODE (target
)
3043 != promote_mode (type
, TYPE_MODE (type
), &unsignedp
, 1))
3046 if ((WORDS_BIG_ENDIAN
|| BYTES_BIG_ENDIAN
)
3047 && GET_MODE_SIZE (GET_MODE (target
))
3048 > GET_MODE_SIZE (TYPE_MODE (type
)))
3050 offset
= GET_MODE_SIZE (GET_MODE (target
))
3051 - GET_MODE_SIZE (TYPE_MODE (type
));
3052 if (! BYTES_BIG_ENDIAN
)
3053 offset
= (offset
/ UNITS_PER_WORD
) * UNITS_PER_WORD
;
3054 else if (! WORDS_BIG_ENDIAN
)
3055 offset
%= UNITS_PER_WORD
;
3057 target
= gen_rtx_SUBREG (TYPE_MODE (type
), target
, offset
);
3058 SUBREG_PROMOTED_VAR_P (target
) = 1;
3059 SUBREG_PROMOTED_UNSIGNED_SET (target
, unsignedp
);
3063 /* If size of args is variable or this was a constructor call for a stack
3064 argument, restore saved stack-pointer value. */
3066 if (old_stack_level
&& ! (flags
& ECF_SP_DEPRESSED
))
3068 emit_stack_restore (SAVE_BLOCK
, old_stack_level
, NULL_RTX
);
3069 stack_pointer_delta
= old_stack_pointer_delta
;
3070 pending_stack_adjust
= old_pending_adj
;
3071 stack_arg_under_construction
= old_stack_arg_under_construction
;
3072 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3073 stack_usage_map
= initial_stack_usage_map
;
3074 sibcall_failure
= 1;
3076 else if (ACCUMULATE_OUTGOING_ARGS
&& pass
)
3078 #ifdef REG_PARM_STACK_SPACE
3080 restore_fixed_argument_area (save_area
, argblock
,
3081 high_to_save
, low_to_save
);
3084 /* If we saved any argument areas, restore them. */
3085 for (i
= 0; i
< num_actuals
; i
++)
3086 if (args
[i
].save_area
)
3088 enum machine_mode save_mode
= GET_MODE (args
[i
].save_area
);
3090 = gen_rtx_MEM (save_mode
,
3091 memory_address (save_mode
,
3092 XEXP (args
[i
].stack_slot
, 0)));
3094 if (save_mode
!= BLKmode
)
3095 emit_move_insn (stack_area
, args
[i
].save_area
);
3097 emit_block_move (stack_area
, args
[i
].save_area
,
3098 GEN_INT (args
[i
].locate
.size
.constant
),
3099 BLOCK_OP_CALL_PARM
);
3102 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
3103 stack_usage_map
= initial_stack_usage_map
;
3106 /* If this was alloca, record the new stack level for nonlocal gotos.
3107 Check for the handler slots since we might not have a save area
3108 for non-local gotos. */
3110 if ((flags
& ECF_MAY_BE_ALLOCA
) && cfun
->nonlocal_goto_save_area
!= 0)
3111 update_nonlocal_goto_save_area ();
3113 /* Free up storage we no longer need. */
3114 for (i
= 0; i
< num_actuals
; ++i
)
3115 if (args
[i
].aligned_regs
)
3116 free (args
[i
].aligned_regs
);
3120 /* Undo the fake expand_start_target_temps we did earlier. If
3121 there had been any cleanups created, we've already set
3123 expand_end_target_temps ();
3126 /* If this function is returning into a memory location marked as
3127 readonly, it means it is initializing that location. We normally treat
3128 functions as not clobbering such locations, so we need to specify that
3129 this one does. We do this by adding the appropriate CLOBBER to the
3130 CALL_INSN function usage list. This cannot be done by emitting a
3131 standalone CLOBBER after the call because the latter would be ignored
3132 by at least the delay slot scheduling pass. We do this now instead of
3133 adding to call_fusage before the call to emit_call_1 because TARGET
3134 may be modified in the meantime. */
3135 if (structure_value_addr
!= 0 && target
!= 0
3136 && MEM_P (target
) && RTX_UNCHANGING_P (target
))
3137 add_function_usage_to
3139 gen_rtx_EXPR_LIST (VOIDmode
, gen_rtx_CLOBBER (VOIDmode
, target
),
3142 insns
= get_insns ();
3147 tail_call_insns
= insns
;
3149 /* Restore the pending stack adjustment now that we have
3150 finished generating the sibling call sequence. */
3152 pending_stack_adjust
= save_pending_stack_adjust
;
3153 stack_pointer_delta
= save_stack_pointer_delta
;
3155 /* Prepare arg structure for next iteration. */
3156 for (i
= 0; i
< num_actuals
; i
++)
3159 args
[i
].aligned_regs
= 0;
3163 sbitmap_free (stored_args_map
);
3167 normal_call_insns
= insns
;
3169 /* Verify that we've deallocated all the stack we used. */
3170 if (! (flags
& (ECF_NORETURN
| ECF_LONGJMP
))
3171 && old_stack_allocated
!= stack_pointer_delta
3172 - pending_stack_adjust
)
3176 /* If something prevents making this a sibling call,
3177 zero out the sequence. */
3178 if (sibcall_failure
)
3179 tail_call_insns
= NULL_RTX
;
3184 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3185 arguments too, as argument area is now clobbered by the call. */
3186 if (tail_call_insns
)
3188 emit_insn (tail_call_insns
);
3189 cfun
->tail_call_emit
= true;
3192 emit_insn (normal_call_insns
);
3194 currently_expanding_call
--;
3196 /* If this function returns with the stack pointer depressed, ensure
3197 this block saves and restores the stack pointer, show it was
3198 changed, and adjust for any outgoing arg space. */
3199 if (flags
& ECF_SP_DEPRESSED
)
3201 clear_pending_stack_adjust ();
3202 emit_insn (gen_rtx_CLOBBER (VOIDmode
, stack_pointer_rtx
));
3203 emit_move_insn (virtual_stack_dynamic_rtx
, stack_pointer_rtx
);
3209 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3210 this function's incoming arguments.
3212 At the start of RTL generation we know the only REG_EQUIV notes
3213 in the rtl chain are those for incoming arguments, so we can safely
3214 flush any REG_EQUIV note.
3216 This is (slight) overkill. We could keep track of the highest
3217 argument we clobber and be more selective in removing notes, but it
3218 does not seem to be worth the effort. */
3220 fixup_tail_calls (void)
3225 purge_reg_equiv_notes ();
3227 /* A sibling call sequence also may invalidate RTX_UNCHANGING_P
3228 flag of some incoming arguments MEM RTLs, because it can write into
3229 those slots. We clear all those bits now.
3231 This is (slight) overkill, we could keep track of which arguments
3232 we actually write into. */
3233 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
3236 purge_mem_unchanging_flag (PATTERN (insn
));
3239 /* Similarly, invalidate RTX_UNCHANGING_P for any incoming
3240 arguments passed in registers. */
3241 for (arg
= DECL_ARGUMENTS (current_function_decl
);
3243 arg
= TREE_CHAIN (arg
))
3245 if (REG_P (DECL_RTL (arg
)))
3246 RTX_UNCHANGING_P (DECL_RTL (arg
)) = false;
3250 /* Traverse an argument list in VALUES and expand all complex
3251 arguments into their components. */
3253 split_complex_values (tree values
)
3257 /* Before allocating memory, check for the common case of no complex. */
3258 for (p
= values
; p
; p
= TREE_CHAIN (p
))
3260 tree type
= TREE_TYPE (TREE_VALUE (p
));
3261 if (type
&& TREE_CODE (type
) == COMPLEX_TYPE
3262 && targetm
.calls
.split_complex_arg (type
))
3268 values
= copy_list (values
);
3270 for (p
= values
; p
; p
= TREE_CHAIN (p
))
3272 tree complex_value
= TREE_VALUE (p
);
3275 complex_type
= TREE_TYPE (complex_value
);
3279 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
3280 && targetm
.calls
.split_complex_arg (complex_type
))
3283 tree real
, imag
, next
;
3285 subtype
= TREE_TYPE (complex_type
);
3286 complex_value
= save_expr (complex_value
);
3287 real
= build1 (REALPART_EXPR
, subtype
, complex_value
);
3288 imag
= build1 (IMAGPART_EXPR
, subtype
, complex_value
);
3290 TREE_VALUE (p
) = real
;
3291 next
= TREE_CHAIN (p
);
3292 imag
= build_tree_list (NULL_TREE
, imag
);
3293 TREE_CHAIN (p
) = imag
;
3294 TREE_CHAIN (imag
) = next
;
3296 /* Skip the newly created node. */
3304 /* Traverse a list of TYPES and expand all complex types into their
3307 split_complex_types (tree types
)
3311 /* Before allocating memory, check for the common case of no complex. */
3312 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3314 tree type
= TREE_VALUE (p
);
3315 if (TREE_CODE (type
) == COMPLEX_TYPE
3316 && targetm
.calls
.split_complex_arg (type
))
3322 types
= copy_list (types
);
3324 for (p
= types
; p
; p
= TREE_CHAIN (p
))
3326 tree complex_type
= TREE_VALUE (p
);
3328 if (TREE_CODE (complex_type
) == COMPLEX_TYPE
3329 && targetm
.calls
.split_complex_arg (complex_type
))
3333 /* Rewrite complex type with component type. */
3334 TREE_VALUE (p
) = TREE_TYPE (complex_type
);
3335 next
= TREE_CHAIN (p
);
3337 /* Add another component type for the imaginary part. */
3338 imag
= build_tree_list (NULL_TREE
, TREE_VALUE (p
));
3339 TREE_CHAIN (p
) = imag
;
3340 TREE_CHAIN (imag
) = next
;
3342 /* Skip the newly created node. */
3350 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3351 The RETVAL parameter specifies whether return value needs to be saved, other
3352 parameters are documented in the emit_library_call function below. */
3355 emit_library_call_value_1 (int retval
, rtx orgfun
, rtx value
,
3356 enum libcall_type fn_type
,
3357 enum machine_mode outmode
, int nargs
, va_list p
)
3359 /* Total size in bytes of all the stack-parms scanned so far. */
3360 struct args_size args_size
;
3361 /* Size of arguments before any adjustments (such as rounding). */
3362 struct args_size original_args_size
;
3368 CUMULATIVE_ARGS args_so_far
;
3372 enum machine_mode mode
;
3375 struct locate_and_pad_arg_data locate
;
3379 int old_inhibit_defer_pop
= inhibit_defer_pop
;
3380 rtx call_fusage
= 0;
3383 int pcc_struct_value
= 0;
3384 int struct_value_size
= 0;
3386 int reg_parm_stack_space
= 0;
3389 tree tfom
; /* type_for_mode (outmode, 0) */
3391 #ifdef REG_PARM_STACK_SPACE
3392 /* Define the boundary of the register parm stack space that needs to be
3394 int low_to_save
, high_to_save
;
3395 rtx save_area
= 0; /* Place that it is saved. */
3398 /* Size of the stack reserved for parameter registers. */
3399 int initial_highest_arg_in_use
= highest_outgoing_arg_in_use
;
3400 char *initial_stack_usage_map
= stack_usage_map
;
3402 rtx struct_value
= targetm
.calls
.struct_value_rtx (0, 0);
3404 #ifdef REG_PARM_STACK_SPACE
3405 reg_parm_stack_space
= REG_PARM_STACK_SPACE ((tree
) 0);
3408 /* By default, library functions can not throw. */
3409 flags
= ECF_NOTHROW
;
3421 case LCT_CONST_MAKE_BLOCK
:
3422 flags
|= ECF_CONST
| ECF_LIBCALL_BLOCK
;
3424 case LCT_PURE_MAKE_BLOCK
:
3425 flags
|= ECF_PURE
| ECF_LIBCALL_BLOCK
;
3428 flags
|= ECF_NORETURN
;
3431 flags
= ECF_NORETURN
;
3433 case LCT_ALWAYS_RETURN
:
3434 flags
= ECF_ALWAYS_RETURN
;
3436 case LCT_RETURNS_TWICE
:
3437 flags
= ECF_RETURNS_TWICE
;
3442 /* Ensure current function's preferred stack boundary is at least
3444 if (cfun
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
3445 cfun
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
3447 /* If this kind of value comes back in memory,
3448 decide where in memory it should come back. */
3449 if (outmode
!= VOIDmode
)
3451 tfom
= lang_hooks
.types
.type_for_mode (outmode
, 0);
3452 if (aggregate_value_p (tfom
, 0))
3454 #ifdef PCC_STATIC_STRUCT_RETURN
3456 = hard_function_value (build_pointer_type (tfom
), 0, 0);
3457 mem_value
= gen_rtx_MEM (outmode
, pointer_reg
);
3458 pcc_struct_value
= 1;
3460 value
= gen_reg_rtx (outmode
);
3461 #else /* not PCC_STATIC_STRUCT_RETURN */
3462 struct_value_size
= GET_MODE_SIZE (outmode
);
3463 if (value
!= 0 && MEM_P (value
))
3466 mem_value
= assign_temp (tfom
, 0, 1, 1);
3468 /* This call returns a big structure. */
3469 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3473 tfom
= void_type_node
;
3475 /* ??? Unfinished: must pass the memory address as an argument. */
3477 /* Copy all the libcall-arguments out of the varargs data
3478 and into a vector ARGVEC.
3480 Compute how to pass each argument. We only support a very small subset
3481 of the full argument passing conventions to limit complexity here since
3482 library functions shouldn't have many args. */
3484 argvec
= alloca ((nargs
+ 1) * sizeof (struct arg
));
3485 memset (argvec
, 0, (nargs
+ 1) * sizeof (struct arg
));
3487 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3488 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far
, outmode
, fun
);
3490 INIT_CUMULATIVE_ARGS (args_so_far
, NULL_TREE
, fun
, 0, nargs
);
3493 args_size
.constant
= 0;
3498 /* Now we are about to start emitting insns that can be deleted
3499 if a libcall is deleted. */
3500 if (flags
& ECF_LIBCALL_BLOCK
)
3505 /* If there's a structure value address to be passed,
3506 either pass it in the special place, or pass it as an extra argument. */
3507 if (mem_value
&& struct_value
== 0 && ! pcc_struct_value
)
3509 rtx addr
= XEXP (mem_value
, 0);
3512 /* Make sure it is a reasonable operand for a move or push insn. */
3513 if (!REG_P (addr
) && !MEM_P (addr
)
3514 && ! (CONSTANT_P (addr
) && LEGITIMATE_CONSTANT_P (addr
)))
3515 addr
= force_operand (addr
, NULL_RTX
);
3517 argvec
[count
].value
= addr
;
3518 argvec
[count
].mode
= Pmode
;
3519 argvec
[count
].partial
= 0;
3521 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, Pmode
, NULL_TREE
, 1);
3522 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, Pmode
, NULL_TREE
, 1))
3525 locate_and_pad_parm (Pmode
, NULL_TREE
,
3526 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3529 argvec
[count
].reg
!= 0,
3531 0, NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3533 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3534 || reg_parm_stack_space
> 0)
3535 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3537 FUNCTION_ARG_ADVANCE (args_so_far
, Pmode
, (tree
) 0, 1);
3542 for (; count
< nargs
; count
++)
3544 rtx val
= va_arg (p
, rtx
);
3545 enum machine_mode mode
= va_arg (p
, enum machine_mode
);
3547 /* We cannot convert the arg value to the mode the library wants here;
3548 must do it earlier where we know the signedness of the arg. */
3550 || (GET_MODE (val
) != mode
&& GET_MODE (val
) != VOIDmode
))
3553 /* There's no need to call protect_from_queue, because
3554 either emit_move_insn or emit_push_insn will do that. */
3556 /* Make sure it is a reasonable operand for a move or push insn. */
3557 if (!REG_P (val
) && !MEM_P (val
)
3558 && ! (CONSTANT_P (val
) && LEGITIMATE_CONSTANT_P (val
)))
3559 val
= force_operand (val
, NULL_RTX
);
3561 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far
, mode
, NULL_TREE
, 1))
3564 int must_copy
= ! FUNCTION_ARG_CALLEE_COPIES (args_so_far
, mode
,
3567 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3568 functions, so we have to pretend this isn't such a function. */
3569 if (flags
& ECF_LIBCALL_BLOCK
)
3571 rtx insns
= get_insns ();
3575 flags
&= ~(ECF_CONST
| ECF_PURE
| ECF_LIBCALL_BLOCK
);
3577 /* If this was a CONST function, it is now PURE since
3578 it now reads memory. */
3579 if (flags
& ECF_CONST
)
3581 flags
&= ~ECF_CONST
;
3585 if (GET_MODE (val
) == MEM
&& ! must_copy
)
3589 slot
= assign_temp (lang_hooks
.types
.type_for_mode (mode
, 0),
3591 emit_move_insn (slot
, val
);
3595 tree type
= lang_hooks
.types
.type_for_mode (mode
, 0);
3598 = gen_rtx_MEM (mode
,
3599 expand_expr (build1 (ADDR_EXPR
,
3600 build_pointer_type (type
),
3601 make_tree (type
, val
)),
3602 NULL_RTX
, VOIDmode
, 0));
3605 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3606 gen_rtx_USE (VOIDmode
, slot
),
3609 call_fusage
= gen_rtx_EXPR_LIST (VOIDmode
,
3610 gen_rtx_CLOBBER (VOIDmode
,
3615 val
= force_operand (XEXP (slot
, 0), NULL_RTX
);
3618 argvec
[count
].value
= val
;
3619 argvec
[count
].mode
= mode
;
3621 argvec
[count
].reg
= FUNCTION_ARG (args_so_far
, mode
, NULL_TREE
, 1);
3623 argvec
[count
].partial
3624 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, mode
, NULL_TREE
, 1);
3626 locate_and_pad_parm (mode
, NULL_TREE
,
3627 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3630 argvec
[count
].reg
!= 0,
3632 argvec
[count
].partial
,
3633 NULL_TREE
, &args_size
, &argvec
[count
].locate
);
3635 if (argvec
[count
].locate
.size
.var
)
3638 if (argvec
[count
].reg
== 0 || argvec
[count
].partial
!= 0
3639 || reg_parm_stack_space
> 0)
3640 args_size
.constant
+= argvec
[count
].locate
.size
.constant
;
3642 FUNCTION_ARG_ADVANCE (args_so_far
, mode
, (tree
) 0, 1);
3645 /* If this machine requires an external definition for library
3646 functions, write one out. */
3647 assemble_external_libcall (fun
);
3649 original_args_size
= args_size
;
3650 args_size
.constant
= (((args_size
.constant
3651 + stack_pointer_delta
3655 - stack_pointer_delta
);
3657 args_size
.constant
= MAX (args_size
.constant
,
3658 reg_parm_stack_space
);
3660 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3661 args_size
.constant
-= reg_parm_stack_space
;
3664 if (args_size
.constant
> current_function_outgoing_args_size
)
3665 current_function_outgoing_args_size
= args_size
.constant
;
3667 if (ACCUMULATE_OUTGOING_ARGS
)
3669 /* Since the stack pointer will never be pushed, it is possible for
3670 the evaluation of a parm to clobber something we have already
3671 written to the stack. Since most function calls on RISC machines
3672 do not use the stack, this is uncommon, but must work correctly.
3674 Therefore, we save any area of the stack that was already written
3675 and that we are using. Here we set up to do this by making a new
3676 stack usage map from the old one.
3678 Another approach might be to try to reorder the argument
3679 evaluations to avoid this conflicting stack usage. */
3681 needed
= args_size
.constant
;
3683 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3684 /* Since we will be writing into the entire argument area, the
3685 map must be allocated for its entire size, not just the part that
3686 is the responsibility of the caller. */
3687 needed
+= reg_parm_stack_space
;
3690 #ifdef ARGS_GROW_DOWNWARD
3691 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3694 highest_outgoing_arg_in_use
= MAX (initial_highest_arg_in_use
,
3697 stack_usage_map
= alloca (highest_outgoing_arg_in_use
);
3699 if (initial_highest_arg_in_use
)
3700 memcpy (stack_usage_map
, initial_stack_usage_map
,
3701 initial_highest_arg_in_use
);
3703 if (initial_highest_arg_in_use
!= highest_outgoing_arg_in_use
)
3704 memset (&stack_usage_map
[initial_highest_arg_in_use
], 0,
3705 highest_outgoing_arg_in_use
- initial_highest_arg_in_use
);
3708 /* We must be careful to use virtual regs before they're instantiated,
3709 and real regs afterwards. Loop optimization, for example, can create
3710 new libcalls after we've instantiated the virtual regs, and if we
3711 use virtuals anyway, they won't match the rtl patterns. */
3713 if (virtuals_instantiated
)
3714 argblock
= plus_constant (stack_pointer_rtx
, STACK_POINTER_OFFSET
);
3716 argblock
= virtual_outgoing_args_rtx
;
3721 argblock
= push_block (GEN_INT (args_size
.constant
), 0, 0);
3724 /* If we push args individually in reverse order, perform stack alignment
3725 before the first push (the last arg). */
3726 if (argblock
== 0 && PUSH_ARGS_REVERSED
)
3727 anti_adjust_stack (GEN_INT (args_size
.constant
3728 - original_args_size
.constant
));
3730 if (PUSH_ARGS_REVERSED
)
3741 #ifdef REG_PARM_STACK_SPACE
3742 if (ACCUMULATE_OUTGOING_ARGS
)
3744 /* The argument list is the property of the called routine and it
3745 may clobber it. If the fixed area has been used for previous
3746 parameters, we must save and restore it. */
3747 save_area
= save_fixed_argument_area (reg_parm_stack_space
, argblock
,
3748 &low_to_save
, &high_to_save
);
3752 /* Push the args that need to be pushed. */
3754 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3755 are to be pushed. */
3756 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3758 enum machine_mode mode
= argvec
[argnum
].mode
;
3759 rtx val
= argvec
[argnum
].value
;
3760 rtx reg
= argvec
[argnum
].reg
;
3761 int partial
= argvec
[argnum
].partial
;
3762 int lower_bound
= 0, upper_bound
= 0, i
;
3764 if (! (reg
!= 0 && partial
== 0))
3766 if (ACCUMULATE_OUTGOING_ARGS
)
3768 /* If this is being stored into a pre-allocated, fixed-size,
3769 stack area, save any previous data at that location. */
3771 #ifdef ARGS_GROW_DOWNWARD
3772 /* stack_slot is negative, but we want to index stack_usage_map
3773 with positive values. */
3774 upper_bound
= -argvec
[argnum
].locate
.offset
.constant
+ 1;
3775 lower_bound
= upper_bound
- argvec
[argnum
].locate
.size
.constant
;
3777 lower_bound
= argvec
[argnum
].locate
.offset
.constant
;
3778 upper_bound
= lower_bound
+ argvec
[argnum
].locate
.size
.constant
;
3782 /* Don't worry about things in the fixed argument area;
3783 it has already been saved. */
3784 if (i
< reg_parm_stack_space
)
3785 i
= reg_parm_stack_space
;
3786 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
3789 if (i
< upper_bound
)
3791 /* We need to make a save area. */
3793 = argvec
[argnum
].locate
.size
.constant
* BITS_PER_UNIT
;
3794 enum machine_mode save_mode
3795 = mode_for_size (size
, MODE_INT
, 1);
3797 = plus_constant (argblock
,
3798 argvec
[argnum
].locate
.offset
.constant
);
3800 = gen_rtx_MEM (save_mode
, memory_address (save_mode
, adr
));
3802 if (save_mode
== BLKmode
)
3804 argvec
[argnum
].save_area
3805 = assign_stack_temp (BLKmode
,
3806 argvec
[argnum
].locate
.size
.constant
,
3809 emit_block_move (validize_mem (argvec
[argnum
].save_area
),
3811 GEN_INT (argvec
[argnum
].locate
.size
.constant
),
3812 BLOCK_OP_CALL_PARM
);
3816 argvec
[argnum
].save_area
= gen_reg_rtx (save_mode
);
3818 emit_move_insn (argvec
[argnum
].save_area
, stack_area
);
3823 emit_push_insn (val
, mode
, NULL_TREE
, NULL_RTX
, PARM_BOUNDARY
,
3824 partial
, reg
, 0, argblock
,
3825 GEN_INT (argvec
[argnum
].locate
.offset
.constant
),
3826 reg_parm_stack_space
,
3827 ARGS_SIZE_RTX (argvec
[argnum
].locate
.alignment_pad
));
3829 /* Now mark the segment we just used. */
3830 if (ACCUMULATE_OUTGOING_ARGS
)
3831 for (i
= lower_bound
; i
< upper_bound
; i
++)
3832 stack_usage_map
[i
] = 1;
3838 /* If we pushed args in forward order, perform stack alignment
3839 after pushing the last arg. */
3840 if (argblock
== 0 && !PUSH_ARGS_REVERSED
)
3841 anti_adjust_stack (GEN_INT (args_size
.constant
3842 - original_args_size
.constant
));
3844 if (PUSH_ARGS_REVERSED
)
3849 fun
= prepare_call_address (fun
, NULL
, &call_fusage
, 0, 0);
3851 /* Now load any reg parms into their regs. */
3853 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3854 are to be pushed. */
3855 for (count
= 0; count
< nargs
; count
++, argnum
+= inc
)
3857 enum machine_mode mode
= argvec
[argnum
].mode
;
3858 rtx val
= argvec
[argnum
].value
;
3859 rtx reg
= argvec
[argnum
].reg
;
3860 int partial
= argvec
[argnum
].partial
;
3862 /* Handle calls that pass values in multiple non-contiguous
3863 locations. The PA64 has examples of this for library calls. */
3864 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3865 emit_group_load (reg
, val
, NULL_TREE
, GET_MODE_SIZE (mode
));
3866 else if (reg
!= 0 && partial
== 0)
3867 emit_move_insn (reg
, val
);
3872 /* Any regs containing parms remain in use through the call. */
3873 for (count
= 0; count
< nargs
; count
++)
3875 rtx reg
= argvec
[count
].reg
;
3876 if (reg
!= 0 && GET_CODE (reg
) == PARALLEL
)
3877 use_group_regs (&call_fusage
, reg
);
3879 use_reg (&call_fusage
, reg
);
3882 /* Pass the function the address in which to return a structure value. */
3883 if (mem_value
!= 0 && struct_value
!= 0 && ! pcc_struct_value
)
3885 emit_move_insn (struct_value
,
3887 force_operand (XEXP (mem_value
, 0),
3889 if (REG_P (struct_value
))
3890 use_reg (&call_fusage
, struct_value
);
3893 /* Don't allow popping to be deferred, since then
3894 cse'ing of library calls could delete a call and leave the pop. */
3896 valreg
= (mem_value
== 0 && outmode
!= VOIDmode
3897 ? hard_libcall_value (outmode
) : NULL_RTX
);
3899 /* Stack must be properly aligned now. */
3900 if (stack_pointer_delta
& (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
- 1))
3903 before_call
= get_last_insn ();
3905 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3906 will set inhibit_defer_pop to that value. */
3907 /* The return type is needed to decide how many bytes the function pops.
3908 Signedness plays no role in that, so for simplicity, we pretend it's
3909 always signed. We also assume that the list of arguments passed has
3910 no impact, so we pretend it is unknown. */
3912 emit_call_1 (fun
, NULL
,
3913 get_identifier (XSTR (orgfun
, 0)),
3914 build_function_type (tfom
, NULL_TREE
),
3915 original_args_size
.constant
, args_size
.constant
,
3917 FUNCTION_ARG (args_so_far
, VOIDmode
, void_type_node
, 1),
3919 old_inhibit_defer_pop
+ 1, call_fusage
, flags
, & args_so_far
);
3921 /* For calls to `setjmp', etc., inform flow.c it should complain
3922 if nonvolatile values are live. For functions that cannot return,
3923 inform flow that control does not fall through. */
3925 if (flags
& (ECF_NORETURN
| ECF_LONGJMP
))
3927 /* The barrier note must be emitted
3928 immediately after the CALL_INSN. Some ports emit more than
3929 just a CALL_INSN above, so we must search for it here. */
3931 rtx last
= get_last_insn ();
3932 while (!CALL_P (last
))
3934 last
= PREV_INSN (last
);
3935 /* There was no CALL_INSN? */
3936 if (last
== before_call
)
3940 emit_barrier_after (last
);
3943 /* Now restore inhibit_defer_pop to its actual original value. */
3946 /* If call is cse'able, make appropriate pair of reg-notes around it.
3947 Test valreg so we don't crash; may safely ignore `const'
3948 if return type is void. Disable for PARALLEL return values, because
3949 we have no way to move such values into a pseudo register. */
3950 if (flags
& ECF_LIBCALL_BLOCK
)
3956 insns
= get_insns ();
3966 if (GET_CODE (valreg
) == PARALLEL
)
3968 temp
= gen_reg_rtx (outmode
);
3969 emit_group_store (temp
, valreg
, NULL_TREE
,
3970 GET_MODE_SIZE (outmode
));
3974 temp
= gen_reg_rtx (GET_MODE (valreg
));
3976 /* Construct an "equal form" for the value which mentions all the
3977 arguments in order as well as the function name. */
3978 for (i
= 0; i
< nargs
; i
++)
3979 note
= gen_rtx_EXPR_LIST (VOIDmode
, argvec
[i
].value
, note
);
3980 note
= gen_rtx_EXPR_LIST (VOIDmode
, fun
, note
);
3982 insns
= get_insns ();
3985 if (flags
& ECF_PURE
)
3986 note
= gen_rtx_EXPR_LIST (VOIDmode
,
3987 gen_rtx_USE (VOIDmode
,
3988 gen_rtx_MEM (BLKmode
,
3989 gen_rtx_SCRATCH (VOIDmode
))),
3992 emit_libcall_block (insns
, temp
, valreg
, note
);
3999 /* Copy the value to the right place. */
4000 if (outmode
!= VOIDmode
&& retval
)
4006 if (value
!= mem_value
)
4007 emit_move_insn (value
, mem_value
);
4009 else if (GET_CODE (valreg
) == PARALLEL
)
4012 value
= gen_reg_rtx (outmode
);
4013 emit_group_store (value
, valreg
, NULL_TREE
, GET_MODE_SIZE (outmode
));
4015 else if (value
!= 0)
4016 emit_move_insn (value
, valreg
);
4021 if (ACCUMULATE_OUTGOING_ARGS
)
4023 #ifdef REG_PARM_STACK_SPACE
4025 restore_fixed_argument_area (save_area
, argblock
,
4026 high_to_save
, low_to_save
);
4029 /* If we saved any argument areas, restore them. */
4030 for (count
= 0; count
< nargs
; count
++)
4031 if (argvec
[count
].save_area
)
4033 enum machine_mode save_mode
= GET_MODE (argvec
[count
].save_area
);
4034 rtx adr
= plus_constant (argblock
,
4035 argvec
[count
].locate
.offset
.constant
);
4036 rtx stack_area
= gen_rtx_MEM (save_mode
,
4037 memory_address (save_mode
, adr
));
4039 if (save_mode
== BLKmode
)
4040 emit_block_move (stack_area
,
4041 validize_mem (argvec
[count
].save_area
),
4042 GEN_INT (argvec
[count
].locate
.size
.constant
),
4043 BLOCK_OP_CALL_PARM
);
4045 emit_move_insn (stack_area
, argvec
[count
].save_area
);
4048 highest_outgoing_arg_in_use
= initial_highest_arg_in_use
;
4049 stack_usage_map
= initial_stack_usage_map
;
4056 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4057 (emitting the queue unless NO_QUEUE is nonzero),
4058 for a value of mode OUTMODE,
4059 with NARGS different arguments, passed as alternating rtx values
4060 and machine_modes to convert them to.
4061 The rtx values should have been passed through protect_from_queue already.
4063 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4064 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4065 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4066 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4067 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4068 or other LCT_ value for other types of library calls. */
4071 emit_library_call (rtx orgfun
, enum libcall_type fn_type
,
4072 enum machine_mode outmode
, int nargs
, ...)
4076 va_start (p
, nargs
);
4077 emit_library_call_value_1 (0, orgfun
, NULL_RTX
, fn_type
, outmode
, nargs
, p
);
4081 /* Like emit_library_call except that an extra argument, VALUE,
4082 comes second and says where to store the result.
4083 (If VALUE is zero, this function chooses a convenient way
4084 to return the value.
4086 This function returns an rtx for where the value is to be found.
4087 If VALUE is nonzero, VALUE is returned. */
4090 emit_library_call_value (rtx orgfun
, rtx value
,
4091 enum libcall_type fn_type
,
4092 enum machine_mode outmode
, int nargs
, ...)
4097 va_start (p
, nargs
);
4098 result
= emit_library_call_value_1 (1, orgfun
, value
, fn_type
, outmode
,
4105 /* Store a single argument for a function call
4106 into the register or memory area where it must be passed.
4107 *ARG describes the argument value and where to pass it.
4109 ARGBLOCK is the address of the stack-block for all the arguments,
4110 or 0 on a machine where arguments are pushed individually.
4112 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4113 so must be careful about how the stack is used.
4115 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4116 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4117 that we need not worry about saving and restoring the stack.
4119 FNDECL is the declaration of the function we are calling.
4121 Return nonzero if this arg should cause sibcall failure,
4125 store_one_arg (struct arg_data
*arg
, rtx argblock
, int flags
,
4126 int variable_size ATTRIBUTE_UNUSED
, int reg_parm_stack_space
)
4128 tree pval
= arg
->tree_value
;
4132 int i
, lower_bound
= 0, upper_bound
= 0;
4133 int sibcall_failure
= 0;
4135 if (TREE_CODE (pval
) == ERROR_MARK
)
4138 /* Push a new temporary level for any temporaries we make for
4142 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
))
4144 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4145 save any previous data at that location. */
4146 if (argblock
&& ! variable_size
&& arg
->stack
)
4148 #ifdef ARGS_GROW_DOWNWARD
4149 /* stack_slot is negative, but we want to index stack_usage_map
4150 with positive values. */
4151 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4152 upper_bound
= -INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1)) + 1;
4156 lower_bound
= upper_bound
- arg
->locate
.size
.constant
;
4158 if (GET_CODE (XEXP (arg
->stack_slot
, 0)) == PLUS
)
4159 lower_bound
= INTVAL (XEXP (XEXP (arg
->stack_slot
, 0), 1));
4163 upper_bound
= lower_bound
+ arg
->locate
.size
.constant
;
4167 /* Don't worry about things in the fixed argument area;
4168 it has already been saved. */
4169 if (i
< reg_parm_stack_space
)
4170 i
= reg_parm_stack_space
;
4171 while (i
< upper_bound
&& stack_usage_map
[i
] == 0)
4174 if (i
< upper_bound
)
4176 /* We need to make a save area. */
4177 unsigned int size
= arg
->locate
.size
.constant
* BITS_PER_UNIT
;
4178 enum machine_mode save_mode
= mode_for_size (size
, MODE_INT
, 1);
4179 rtx adr
= memory_address (save_mode
, XEXP (arg
->stack_slot
, 0));
4180 rtx stack_area
= gen_rtx_MEM (save_mode
, adr
);
4182 if (save_mode
== BLKmode
)
4184 tree ot
= TREE_TYPE (arg
->tree_value
);
4185 tree nt
= build_qualified_type (ot
, (TYPE_QUALS (ot
)
4186 | TYPE_QUAL_CONST
));
4188 arg
->save_area
= assign_temp (nt
, 0, 1, 1);
4189 preserve_temp_slots (arg
->save_area
);
4190 emit_block_move (validize_mem (arg
->save_area
), stack_area
,
4191 expr_size (arg
->tree_value
),
4192 BLOCK_OP_CALL_PARM
);
4196 arg
->save_area
= gen_reg_rtx (save_mode
);
4197 emit_move_insn (arg
->save_area
, stack_area
);
4203 /* If this isn't going to be placed on both the stack and in registers,
4204 set up the register and number of words. */
4205 if (! arg
->pass_on_stack
)
4207 if (flags
& ECF_SIBCALL
)
4208 reg
= arg
->tail_call_reg
;
4211 partial
= arg
->partial
;
4214 if (reg
!= 0 && partial
== 0)
4215 /* Being passed entirely in a register. We shouldn't be called in
4219 /* If this arg needs special alignment, don't load the registers
4221 if (arg
->n_aligned_regs
!= 0)
4224 /* If this is being passed partially in a register, we can't evaluate
4225 it directly into its stack slot. Otherwise, we can. */
4226 if (arg
->value
== 0)
4228 /* stack_arg_under_construction is nonzero if a function argument is
4229 being evaluated directly into the outgoing argument list and
4230 expand_call must take special action to preserve the argument list
4231 if it is called recursively.
4233 For scalar function arguments stack_usage_map is sufficient to
4234 determine which stack slots must be saved and restored. Scalar
4235 arguments in general have pass_on_stack == 0.
4237 If this argument is initialized by a function which takes the
4238 address of the argument (a C++ constructor or a C function
4239 returning a BLKmode structure), then stack_usage_map is
4240 insufficient and expand_call must push the stack around the
4241 function call. Such arguments have pass_on_stack == 1.
4243 Note that it is always safe to set stack_arg_under_construction,
4244 but this generates suboptimal code if set when not needed. */
4246 if (arg
->pass_on_stack
)
4247 stack_arg_under_construction
++;
4249 arg
->value
= expand_expr (pval
,
4251 || TYPE_MODE (TREE_TYPE (pval
)) != arg
->mode
)
4252 ? NULL_RTX
: arg
->stack
,
4253 VOIDmode
, EXPAND_STACK_PARM
);
4255 /* If we are promoting object (or for any other reason) the mode
4256 doesn't agree, convert the mode. */
4258 if (arg
->mode
!= TYPE_MODE (TREE_TYPE (pval
)))
4259 arg
->value
= convert_modes (arg
->mode
, TYPE_MODE (TREE_TYPE (pval
)),
4260 arg
->value
, arg
->unsignedp
);
4262 if (arg
->pass_on_stack
)
4263 stack_arg_under_construction
--;
4266 /* Don't allow anything left on stack from computation
4267 of argument to alloca. */
4268 if (flags
& ECF_MAY_BE_ALLOCA
)
4269 do_pending_stack_adjust ();
4271 if (arg
->value
== arg
->stack
)
4272 /* If the value is already in the stack slot, we are done. */
4274 else if (arg
->mode
!= BLKmode
)
4278 /* Argument is a scalar, not entirely passed in registers.
4279 (If part is passed in registers, arg->partial says how much
4280 and emit_push_insn will take care of putting it there.)
4282 Push it, and if its size is less than the
4283 amount of space allocated to it,
4284 also bump stack pointer by the additional space.
4285 Note that in C the default argument promotions
4286 will prevent such mismatches. */
4288 size
= GET_MODE_SIZE (arg
->mode
);
4289 /* Compute how much space the push instruction will push.
4290 On many machines, pushing a byte will advance the stack
4291 pointer by a halfword. */
4292 #ifdef PUSH_ROUNDING
4293 size
= PUSH_ROUNDING (size
);
4297 /* Compute how much space the argument should get:
4298 round up to a multiple of the alignment for arguments. */
4299 if (none
!= FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)))
4300 used
= (((size
+ PARM_BOUNDARY
/ BITS_PER_UNIT
- 1)
4301 / (PARM_BOUNDARY
/ BITS_PER_UNIT
))
4302 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
4304 /* This isn't already where we want it on the stack, so put it there.
4305 This can either be done with push or copy insns. */
4306 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), NULL_RTX
,
4307 PARM_BOUNDARY
, partial
, reg
, used
- size
, argblock
,
4308 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4309 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4311 /* Unless this is a partially-in-register argument, the argument is now
4314 arg
->value
= arg
->stack
;
4318 /* BLKmode, at least partly to be pushed. */
4320 unsigned int parm_align
;
4324 /* Pushing a nonscalar.
4325 If part is passed in registers, PARTIAL says how much
4326 and emit_push_insn will take care of putting it there. */
4328 /* Round its size up to a multiple
4329 of the allocation unit for arguments. */
4331 if (arg
->locate
.size
.var
!= 0)
4334 size_rtx
= ARGS_SIZE_RTX (arg
->locate
.size
);
4338 /* PUSH_ROUNDING has no effect on us, because
4339 emit_push_insn for BLKmode is careful to avoid it. */
4340 if (reg
&& GET_CODE (reg
) == PARALLEL
)
4342 /* Use the size of the elt to compute excess. */
4343 rtx elt
= XEXP (XVECEXP (reg
, 0, 0), 0);
4344 excess
= (arg
->locate
.size
.constant
4345 - int_size_in_bytes (TREE_TYPE (pval
))
4346 + partial
* GET_MODE_SIZE (GET_MODE (elt
)));
4349 excess
= (arg
->locate
.size
.constant
4350 - int_size_in_bytes (TREE_TYPE (pval
))
4351 + partial
* UNITS_PER_WORD
);
4352 size_rtx
= expand_expr (size_in_bytes (TREE_TYPE (pval
)),
4353 NULL_RTX
, TYPE_MODE (sizetype
), 0);
4356 /* Some types will require stricter alignment, which will be
4357 provided for elsewhere in argument layout. */
4358 parm_align
= MAX (PARM_BOUNDARY
, TYPE_ALIGN (TREE_TYPE (pval
)));
4360 /* When an argument is padded down, the block is aligned to
4361 PARM_BOUNDARY, but the actual argument isn't. */
4362 if (FUNCTION_ARG_PADDING (arg
->mode
, TREE_TYPE (pval
)) == downward
)
4364 if (arg
->locate
.size
.var
)
4365 parm_align
= BITS_PER_UNIT
;
4368 unsigned int excess_align
= (excess
& -excess
) * BITS_PER_UNIT
;
4369 parm_align
= MIN (parm_align
, excess_align
);
4373 if ((flags
& ECF_SIBCALL
) && MEM_P (arg
->value
))
4375 /* emit_push_insn might not work properly if arg->value and
4376 argblock + arg->locate.offset areas overlap. */
4380 if (XEXP (x
, 0) == current_function_internal_arg_pointer
4381 || (GET_CODE (XEXP (x
, 0)) == PLUS
4382 && XEXP (XEXP (x
, 0), 0) ==
4383 current_function_internal_arg_pointer
4384 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
))
4386 if (XEXP (x
, 0) != current_function_internal_arg_pointer
)
4387 i
= INTVAL (XEXP (XEXP (x
, 0), 1));
4389 /* expand_call should ensure this. */
4390 if (arg
->locate
.offset
.var
|| GET_CODE (size_rtx
) != CONST_INT
)
4393 if (arg
->locate
.offset
.constant
> i
)
4395 if (arg
->locate
.offset
.constant
< i
+ INTVAL (size_rtx
))
4396 sibcall_failure
= 1;
4398 else if (arg
->locate
.offset
.constant
< i
)
4400 if (i
< arg
->locate
.offset
.constant
+ INTVAL (size_rtx
))
4401 sibcall_failure
= 1;
4406 emit_push_insn (arg
->value
, arg
->mode
, TREE_TYPE (pval
), size_rtx
,
4407 parm_align
, partial
, reg
, excess
, argblock
,
4408 ARGS_SIZE_RTX (arg
->locate
.offset
), reg_parm_stack_space
,
4409 ARGS_SIZE_RTX (arg
->locate
.alignment_pad
));
4411 /* Unless this is a partially-in-register argument, the argument is now
4414 ??? Unlike the case above, in which we want the actual
4415 address of the data, so that we can load it directly into a
4416 register, here we want the address of the stack slot, so that
4417 it's properly aligned for word-by-word copying or something
4418 like that. It's not clear that this is always correct. */
4420 arg
->value
= arg
->stack_slot
;
4423 /* Mark all slots this store used. */
4424 if (ACCUMULATE_OUTGOING_ARGS
&& !(flags
& ECF_SIBCALL
)
4425 && argblock
&& ! variable_size
&& arg
->stack
)
4426 for (i
= lower_bound
; i
< upper_bound
; i
++)
4427 stack_usage_map
[i
] = 1;
4429 /* Once we have pushed something, pops can't safely
4430 be deferred during the rest of the arguments. */
4433 /* ANSI doesn't require a sequence point here,
4434 but PCC has one, so this will avoid some problems. */
4437 /* Free any temporary slots made in processing this argument. Show
4438 that we might have taken the address of something and pushed that
4440 preserve_temp_slots (NULL_RTX
);
4444 return sibcall_failure
;
4447 /* Nonzero if we do not know how to pass TYPE solely in registers.
4448 We cannot do so in the following cases:
4450 - if the type has variable size
4451 - if the type is marked as addressable (it is required to be constructed
4453 - if the padding and mode of the type is such that a copy into a register
4454 would put it into the wrong part of the register.
4456 Which padding can't be supported depends on the byte endianness.
4458 A value in a register is implicitly padded at the most significant end.
4459 On a big-endian machine, that is the lower end in memory.
4460 So a value padded in memory at the upper end can't go in a register.
4461 For a little-endian machine, the reverse is true. */
4464 default_must_pass_in_stack (enum machine_mode mode
, tree type
)
4469 /* If the type has variable size... */
4470 if (TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
4473 /* If the type is marked as addressable (it is required
4474 to be constructed into the stack)... */
4475 if (TREE_ADDRESSABLE (type
))
4478 /* If the padding and mode of the type is such that a copy into
4479 a register would put it into the wrong part of the register. */
4481 && int_size_in_bytes (type
) % (PARM_BOUNDARY
/ BITS_PER_UNIT
)
4482 && (FUNCTION_ARG_PADDING (mode
, type
)
4483 == (BYTES_BIG_ENDIAN
? upward
: downward
)))