1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
30 #include "insn-flags.h"
32 /* Decide whether a function's arguments should be processed
33 from first to last or from last to first.
35 They should if the stack and args grow in opposite directions, but
36 only if we have push insns. */
40 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
41 #define PUSH_ARGS_REVERSED /* If it's last to first */
46 /* Like STACK_BOUNDARY but in units of bytes, not bits. */
47 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
49 /* Data structure and subroutines used within expand_call. */
53 /* Tree node for this argument. */
55 /* Mode for value; TYPE_MODE unless promoted. */
56 enum machine_mode mode;
57 /* Current RTL value for argument, or 0 if it isn't precomputed. */
59 /* Initially-compute RTL value for argument; only for const functions. */
61 /* Register to pass this argument in, 0 if passed on stack, or an
62 EXPR_LIST if the arg is to be copied into multiple different
65 /* If REG was promoted from the actual mode of the argument expression,
66 indicates whether the promotion is sign- or zero-extended. */
68 /* Number of registers to use. 0 means put the whole arg in registers.
69 Also 0 if not passed in registers. */
71 /* Non-zero if argument must be passed on stack.
72 Note that some arguments may be passed on the stack
73 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
74 pass_on_stack identifies arguments that *cannot* go in registers. */
76 /* Offset of this argument from beginning of stack-args. */
77 struct args_size offset;
78 /* Similar, but offset to the start of the stack slot. Different from
79 OFFSET if this arg pads downward. */
80 struct args_size slot_offset;
81 /* Size of this argument on the stack, rounded up for any padding it gets,
82 parts of the argument passed in registers do not count.
83 If REG_PARM_STACK_SPACE is defined, then register parms
84 are counted here as well. */
85 struct args_size size;
86 /* Location on the stack at which parameter should be stored. The store
87 has already been done if STACK == VALUE. */
89 /* Location on the stack of the start of this argument slot. This can
90 differ from STACK if this arg pads downward. This location is known
91 to be aligned to FUNCTION_ARG_BOUNDARY. */
93 #ifdef ACCUMULATE_OUTGOING_ARGS
94 /* Place that this stack area has been saved, if needed. */
97 #ifdef STRICT_ALIGNMENT
98 /* If an argument's alignment does not permit direct copying into registers,
99 copy in smaller-sized pieces into pseudos. These are stored in a
100 block pointed to by this field. The next field says how many
101 word-sized pseudos we made. */
107 #ifdef ACCUMULATE_OUTGOING_ARGS
108 /* A vector of one char per byte of stack space. A byte if non-zero if
109 the corresponding stack location has been used.
110 This vector is used to prevent a function call within an argument from
111 clobbering any stack already set up. */
112 static char *stack_usage_map;
114 /* Size of STACK_USAGE_MAP. */
115 static int highest_outgoing_arg_in_use;
117 /* stack_arg_under_construction is nonzero when an argument may be
118 initialized with a constructor call (including a C function that
119 returns a BLKmode struct) and expand_call must take special action
120 to make sure the object being constructed does not overlap the
121 argument list for the constructor call. */
122 int stack_arg_under_construction;
125 static int calls_function PROTO((tree, int));
126 static int calls_function_1 PROTO((tree, int));
127 static void emit_call_1 PROTO((rtx, tree, tree, int, int, rtx, rtx,
129 static void store_one_arg PROTO ((struct arg_data *, rtx, int, int,
132 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
135 If WHICH is 0, return 1 if EXP contains a call to any function.
136 Actually, we only need return 1 if evaluating EXP would require pushing
137 arguments on the stack, but that is too difficult to compute, so we just
138 assume any function call might require the stack. */
140 static tree calls_function_save_exprs;
143 calls_function (exp, which)
148 calls_function_save_exprs = 0;
149 val = calls_function_1 (exp, which);
150 calls_function_save_exprs = 0;
155 calls_function_1 (exp, which)
160 enum tree_code code = TREE_CODE (exp);
161 int type = TREE_CODE_CLASS (code);
162 int length = tree_code_length[(int) code];
164 /* If this code is langauge-specific, we don't know what it will do. */
165 if ((int) code >= NUM_TREE_CODES)
168 /* Only expressions and references can contain calls. */
169 if (type != 'e' && type != '<' && type != '1' && type != '2' && type != 'r'
178 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
179 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
182 tree fndecl = TREE_OPERAND (TREE_OPERAND (exp, 0), 0);
184 if ((DECL_BUILT_IN (fndecl)
185 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_ALLOCA)
186 || (DECL_SAVED_INSNS (fndecl)
187 && (FUNCTION_FLAGS (DECL_SAVED_INSNS (fndecl))
188 & FUNCTION_FLAGS_CALLS_ALLOCA)))
192 /* Third operand is RTL. */
197 if (SAVE_EXPR_RTL (exp) != 0)
199 if (value_member (exp, calls_function_save_exprs))
201 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
202 calls_function_save_exprs);
203 return (TREE_OPERAND (exp, 0) != 0
204 && calls_function_1 (TREE_OPERAND (exp, 0), which));
210 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
211 if (DECL_INITIAL (local) != 0
212 && calls_function_1 (DECL_INITIAL (local), which))
216 register tree subblock;
218 for (subblock = BLOCK_SUBBLOCKS (exp);
220 subblock = TREE_CHAIN (subblock))
221 if (calls_function_1 (subblock, which))
226 case METHOD_CALL_EXPR:
230 case WITH_CLEANUP_EXPR:
238 for (i = 0; i < length; i++)
239 if (TREE_OPERAND (exp, i) != 0
240 && calls_function_1 (TREE_OPERAND (exp, i), which))
246 /* Force FUNEXP into a form suitable for the address of a CALL,
247 and return that as an rtx. Also load the static chain register
248 if FNDECL is a nested function.
250 CALL_FUSAGE points to a variable holding the prospective
251 CALL_INSN_FUNCTION_USAGE information. */
254 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen)
260 rtx static_chain_value = 0;
262 funexp = protect_from_queue (funexp, 0);
265 /* Get possible static chain value for nested function in C. */
266 static_chain_value = lookup_static_chain (fndecl);
268 /* Make a valid memory address and copy constants thru pseudo-regs,
269 but not for a constant address if -fno-function-cse. */
270 if (GET_CODE (funexp) != SYMBOL_REF)
272 #ifdef SMALL_REGISTER_CLASSES
273 /* If we are using registers for parameters, force the
274 function address into a register now. */
275 reg_parm_seen ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
278 memory_address (FUNCTION_MODE, funexp);
281 #ifndef NO_FUNCTION_CSE
282 if (optimize && ! flag_no_function_cse)
283 #ifdef NO_RECURSIVE_FUNCTION_CSE
284 if (fndecl != current_function_decl)
286 funexp = force_reg (Pmode, funexp);
290 if (static_chain_value != 0)
292 emit_move_insn (static_chain_rtx, static_chain_value);
294 use_reg (call_fusage, static_chain_rtx);
300 /* Generate instructions to call function FUNEXP,
301 and optionally pop the results.
302 The CALL_INSN is the first insn generated.
304 FNDECL is the declaration node of the function. This is given ot the
305 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
307 FUNTYPE is the data type of the function, or, for a library call,
308 the identifier for the name of the call. This is given to the
309 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
311 STACK_SIZE is the number of bytes of arguments on the stack,
312 rounded up to STACK_BOUNDARY; zero if the size is variable.
313 This is both to put into the call insn and
314 to generate explicit popping code if necessary.
316 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
317 It is zero if this call doesn't want a structure value.
319 NEXT_ARG_REG is the rtx that results from executing
320 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
321 just after all the args have had their registers assigned.
322 This could be whatever you like, but normally it is the first
323 arg-register beyond those used for args in this call,
324 or 0 if all the arg-registers are used in this call.
325 It is passed on to `gen_call' so you can put this info in the call insn.
327 VALREG is a hard register in which a value is returned,
328 or 0 if the call does not return a value.
330 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
331 the args to this call were processed.
332 We restore `inhibit_defer_pop' to that value.
334 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
335 denote registers used by the called function.
337 IS_CONST is true if this is a `const' call. */
340 emit_call_1 (funexp, fndecl, funtype, stack_size, struct_value_size,
341 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
347 int struct_value_size;
350 int old_inhibit_defer_pop;
354 rtx stack_size_rtx = GEN_INT (stack_size);
355 rtx struct_value_size_rtx = GEN_INT (struct_value_size);
357 int already_popped = 0;
359 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
360 and we don't want to load it into a register as an optimization,
361 because prepare_call_address already did it if it should be done. */
362 if (GET_CODE (funexp) != SYMBOL_REF)
363 funexp = memory_address (FUNCTION_MODE, funexp);
365 #ifndef ACCUMULATE_OUTGOING_ARGS
366 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
367 if (HAVE_call_pop && HAVE_call_value_pop
368 && (RETURN_POPS_ARGS (fndecl, funtype, stack_size) > 0
371 rtx n_pop = GEN_INT (RETURN_POPS_ARGS (fndecl, funtype, stack_size));
374 /* If this subroutine pops its own args, record that in the call insn
375 if possible, for the sake of frame pointer elimination. */
378 pat = gen_call_value_pop (valreg,
379 gen_rtx (MEM, FUNCTION_MODE, funexp),
380 stack_size_rtx, next_arg_reg, n_pop);
382 pat = gen_call_pop (gen_rtx (MEM, FUNCTION_MODE, funexp),
383 stack_size_rtx, next_arg_reg, n_pop);
385 emit_call_insn (pat);
392 #if defined (HAVE_call) && defined (HAVE_call_value)
393 if (HAVE_call && HAVE_call_value)
396 emit_call_insn (gen_call_value (valreg,
397 gen_rtx (MEM, FUNCTION_MODE, funexp),
398 stack_size_rtx, next_arg_reg,
401 emit_call_insn (gen_call (gen_rtx (MEM, FUNCTION_MODE, funexp),
402 stack_size_rtx, next_arg_reg,
403 struct_value_size_rtx));
409 /* Find the CALL insn we just emitted. */
410 for (call_insn = get_last_insn ();
411 call_insn && GET_CODE (call_insn) != CALL_INSN;
412 call_insn = PREV_INSN (call_insn))
418 /* Put the register usage information on the CALL. If there is already
419 some usage information, put ours at the end. */
420 if (CALL_INSN_FUNCTION_USAGE (call_insn))
424 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
425 link = XEXP (link, 1))
428 XEXP (link, 1) = call_fusage;
431 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
433 /* If this is a const call, then set the insn's unchanging bit. */
435 CONST_CALL_P (call_insn) = 1;
437 /* Restore this now, so that we do defer pops for this call's args
438 if the context of the call as a whole permits. */
439 inhibit_defer_pop = old_inhibit_defer_pop;
441 #ifndef ACCUMULATE_OUTGOING_ARGS
442 /* If returning from the subroutine does not automatically pop the args,
443 we need an instruction to pop them sooner or later.
444 Perhaps do it now; perhaps just record how much space to pop later.
446 If returning from the subroutine does pop the args, indicate that the
447 stack pointer will be changed. */
449 if (stack_size != 0 && RETURN_POPS_ARGS (fndecl, funtype, stack_size) > 0)
452 CALL_INSN_FUNCTION_USAGE (call_insn) =
453 gen_rtx (EXPR_LIST, VOIDmode,
454 gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx),
455 CALL_INSN_FUNCTION_USAGE (call_insn));
456 stack_size -= RETURN_POPS_ARGS (fndecl, funtype, stack_size);
457 stack_size_rtx = GEN_INT (stack_size);
462 if (flag_defer_pop && inhibit_defer_pop == 0 && !is_const)
463 pending_stack_adjust += stack_size;
465 adjust_stack (stack_size_rtx);
470 /* Generate all the code for a function call
471 and return an rtx for its value.
472 Store the value in TARGET (specified as an rtx) if convenient.
473 If the value is stored in TARGET then TARGET is returned.
474 If IGNORE is nonzero, then we ignore the value of the function call. */
477 expand_call (exp, target, ignore)
482 /* List of actual parameters. */
483 tree actparms = TREE_OPERAND (exp, 1);
484 /* RTX for the function to be called. */
486 /* Tree node for the function to be called (not the address!). */
488 /* Data type of the function. */
490 /* Declaration of the function being called,
491 or 0 if the function is computed (not known by name). */
495 /* Register in which non-BLKmode value will be returned,
496 or 0 if no value or if value is BLKmode. */
498 /* Address where we should return a BLKmode value;
499 0 if value not BLKmode. */
500 rtx structure_value_addr = 0;
501 /* Nonzero if that address is being passed by treating it as
502 an extra, implicit first parameter. Otherwise,
503 it is passed by being copied directly into struct_value_rtx. */
504 int structure_value_addr_parm = 0;
505 /* Size of aggregate value wanted, or zero if none wanted
506 or if we are using the non-reentrant PCC calling convention
507 or expecting the value in registers. */
508 int struct_value_size = 0;
509 /* Nonzero if called function returns an aggregate in memory PCC style,
510 by returning the address of where to find it. */
511 int pcc_struct_value = 0;
513 /* Number of actual parameters in this call, including struct value addr. */
515 /* Number of named args. Args after this are anonymous ones
516 and they must all go on the stack. */
518 /* Count arg position in order args appear. */
521 /* Vector of information about each argument.
522 Arguments are numbered in the order they will be pushed,
523 not the order they are written. */
524 struct arg_data *args;
526 /* Total size in bytes of all the stack-parms scanned so far. */
527 struct args_size args_size;
528 /* Size of arguments before any adjustments (such as rounding). */
529 struct args_size original_args_size;
530 /* Data on reg parms scanned so far. */
531 CUMULATIVE_ARGS args_so_far;
532 /* Nonzero if a reg parm has been scanned. */
534 /* Nonzero if this is an indirect function call. */
535 int current_call_is_indirect = 0;
537 /* Nonzero if we must avoid push-insns in the args for this call.
538 If stack space is allocated for register parameters, but not by the
539 caller, then it is preallocated in the fixed part of the stack frame.
540 So the entire argument block must then be preallocated (i.e., we
541 ignore PUSH_ROUNDING in that case). */
543 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
544 int must_preallocate = 1;
547 int must_preallocate = 0;
549 int must_preallocate = 1;
553 /* Size of the stack reserved for parameter registers. */
554 int reg_parm_stack_space = 0;
556 /* 1 if scanning parms front to back, -1 if scanning back to front. */
558 /* Address of space preallocated for stack parms
559 (on machines that lack push insns), or 0 if space not preallocated. */
562 /* Nonzero if it is plausible that this is a call to alloca. */
564 /* Nonzero if this is a call to setjmp or a related function. */
566 /* Nonzero if this is a call to `longjmp'. */
568 /* Nonzero if this is a call to an inline function. */
569 int is_integrable = 0;
570 /* Nonzero if this is a call to a `const' function.
571 Note that only explicitly named functions are handled as `const' here. */
573 /* Nonzero if this is a call to a `volatile' function. */
575 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
576 /* Define the boundary of the register parm stack space that needs to be
578 int low_to_save = -1, high_to_save;
579 rtx save_area = 0; /* Place that it is saved */
582 #ifdef ACCUMULATE_OUTGOING_ARGS
583 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
584 char *initial_stack_usage_map = stack_usage_map;
587 rtx old_stack_level = 0;
588 int old_pending_adj = 0;
589 int old_stack_arg_under_construction;
590 int old_inhibit_defer_pop = inhibit_defer_pop;
591 tree old_cleanups = cleanups_this_call;
596 /* See if we can find a DECL-node for the actual function.
597 As a result, decide whether this is a call to an integrable function. */
599 p = TREE_OPERAND (exp, 0);
600 if (TREE_CODE (p) == ADDR_EXPR)
602 fndecl = TREE_OPERAND (p, 0);
603 if (TREE_CODE (fndecl) != FUNCTION_DECL)
608 && fndecl != current_function_decl
609 && DECL_INLINE (fndecl)
610 && DECL_SAVED_INSNS (fndecl))
612 else if (! TREE_ADDRESSABLE (fndecl))
614 /* In case this function later becomes inlinable,
615 record that there was already a non-inline call to it.
617 Use abstraction instead of setting TREE_ADDRESSABLE
619 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline)
620 warning_with_decl (fndecl, "can't inline call to `%s'");
621 mark_addressable (fndecl);
624 if (TREE_READONLY (fndecl) && ! TREE_THIS_VOLATILE (fndecl)
625 && TYPE_MODE (TREE_TYPE (exp)) != VOIDmode)
628 if (TREE_THIS_VOLATILE (fndecl))
633 /* If we don't have specific function to call, see if we have a
634 constant or `noreturn' function from the type. */
637 is_const = TREE_READONLY (TREE_TYPE (TREE_TYPE (p)));
638 is_volatile = TREE_THIS_VOLATILE (TREE_TYPE (TREE_TYPE (p)));
641 #ifdef REG_PARM_STACK_SPACE
642 #ifdef MAYBE_REG_PARM_STACK_SPACE
643 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
645 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
649 /* Warn if this value is an aggregate type,
650 regardless of which calling convention we are using for it. */
651 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
652 warning ("function call has aggregate value");
654 /* Set up a place to return a structure. */
656 /* Cater to broken compilers. */
657 if (aggregate_value_p (exp))
659 /* This call returns a big structure. */
662 #ifdef PCC_STATIC_STRUCT_RETURN
664 pcc_struct_value = 1;
665 /* Easier than making that case work right. */
668 /* In case this is a static function, note that it has been
670 if (! TREE_ADDRESSABLE (fndecl))
671 mark_addressable (fndecl);
675 #else /* not PCC_STATIC_STRUCT_RETURN */
677 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
679 if (target && GET_CODE (target) == MEM)
680 structure_value_addr = XEXP (target, 0);
683 /* Assign a temporary on the stack to hold the value. */
685 /* For variable-sized objects, we must be called with a target
686 specified. If we were to allocate space on the stack here,
687 we would have no way of knowing when to free it. */
689 if (struct_value_size < 0)
693 = XEXP (assign_stack_temp (BLKmode, struct_value_size, 1), 0);
694 MEM_IN_STRUCT_P (structure_value_addr)
695 = AGGREGATE_TYPE_P (TREE_TYPE (exp));
699 #endif /* not PCC_STATIC_STRUCT_RETURN */
702 /* If called function is inline, try to integrate it. */
707 rtx before_call = get_last_insn ();
709 temp = expand_inline_function (fndecl, actparms, target,
710 ignore, TREE_TYPE (exp),
711 structure_value_addr);
713 /* If inlining succeeded, return. */
714 if ((HOST_WIDE_INT) temp != -1)
716 if (flag_short_temps)
718 /* Perform all cleanups needed for the arguments of this
719 call (i.e. destructors in C++). It is ok if these
720 destructors clobber RETURN_VALUE_REG, because the
721 only time we care about this is when TARGET is that
722 register. But in C++, we take care to never return
723 that register directly. */
724 expand_cleanups_to (old_cleanups);
727 #ifdef ACCUMULATE_OUTGOING_ARGS
728 /* If the outgoing argument list must be preserved, push
729 the stack before executing the inlined function if it
732 for (i = reg_parm_stack_space - 1; i >= 0; i--)
733 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
736 if (stack_arg_under_construction || i >= 0)
738 rtx insn = NEXT_INSN (before_call), seq;
740 /* Look for a call in the inline function code.
741 If OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl)) is
742 nonzero then there is a call and it is not necessary
743 to scan the insns. */
745 if (OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl)) == 0)
746 for (; insn; insn = NEXT_INSN (insn))
747 if (GET_CODE (insn) == CALL_INSN)
752 /* Reserve enough stack space so that the largest
753 argument list of any function call in the inline
754 function does not overlap the argument list being
755 evaluated. This is usually an overestimate because
756 allocate_dynamic_stack_space reserves space for an
757 outgoing argument list in addition to the requested
758 space, but there is no way to ask for stack space such
759 that an argument list of a certain length can be
760 safely constructed. */
762 int adjust = OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl));
763 #ifdef REG_PARM_STACK_SPACE
764 /* Add the stack space reserved for register arguments
765 in the inline function. What is really needed is the
766 largest value of reg_parm_stack_space in the inline
767 function, but that is not available. Using the current
768 value of reg_parm_stack_space is wrong, but gives
769 correct results on all supported machines. */
770 adjust += reg_parm_stack_space;
773 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
774 allocate_dynamic_stack_space (GEN_INT (adjust),
775 NULL_RTX, BITS_PER_UNIT);
778 emit_insns_before (seq, NEXT_INSN (before_call));
779 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
784 /* If the result is equivalent to TARGET, return TARGET to simplify
785 checks in store_expr. They can be equivalent but not equal in the
786 case of a function that returns BLKmode. */
787 if (temp != target && rtx_equal_p (temp, target))
792 /* If inlining failed, mark FNDECL as needing to be compiled
793 separately after all. If function was declared inline,
795 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
796 && ! TREE_ADDRESSABLE (fndecl))
797 warning_with_decl (fndecl, "can't inline call to `%s'");
798 mark_addressable (fndecl);
801 /* When calling a const function, we must pop the stack args right away,
802 so that the pop is deleted or moved with the call. */
806 function_call_count++;
808 if (fndecl && DECL_NAME (fndecl))
809 name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
811 /* On some machines (such as the PA) indirect calls have a different
812 calling convention than normal calls. FUNCTION_ARG in the target
813 description can look at current_call_is_indirect to determine which
814 calling convention to use. */
815 current_call_is_indirect = (fndecl == 0);
817 = TREE_CODE (TREE_OPERAND (exp, 0)) == NON_LVALUE_EXPR ? 1 : 0;
821 /* Unless it's a call to a specific function that isn't alloca,
822 if it has one argument, we must assume it might be alloca. */
825 (!(fndecl != 0 && strcmp (name, "alloca"))
827 && TREE_CHAIN (actparms) == 0);
829 /* We assume that alloca will always be called by name. It
830 makes no sense to pass it as a pointer-to-function to
831 anything that does not understand its behavior. */
833 (name && ((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
835 && ! strcmp (name, "alloca"))
836 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
838 && ! strcmp (name, "__builtin_alloca"))));
841 /* See if this is a call to a function that can return more than once
842 or a call to longjmp. */
847 if (name != 0 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 15)
851 /* Disregard prefix _, __ or __x. */
854 if (name[1] == '_' && name[2] == 'x')
856 else if (name[1] == '_')
866 && (! strcmp (tname, "setjmp")
867 || ! strcmp (tname, "setjmp_syscall")))
869 && ! strcmp (tname, "sigsetjmp"))
871 && ! strcmp (tname, "savectx")));
873 && ! strcmp (tname, "siglongjmp"))
876 else if ((tname[0] == 'q' && tname[1] == 's'
877 && ! strcmp (tname, "qsetjmp"))
878 || (tname[0] == 'v' && tname[1] == 'f'
879 && ! strcmp (tname, "vfork")))
882 else if (tname[0] == 'l' && tname[1] == 'o'
883 && ! strcmp (tname, "longjmp"))
888 current_function_calls_alloca = 1;
890 /* Don't let pending stack adjusts add up to too much.
891 Also, do all pending adjustments now
892 if there is any chance this might be a call to alloca. */
894 if (pending_stack_adjust >= 32
895 || (pending_stack_adjust > 0 && may_be_alloca))
896 do_pending_stack_adjust ();
898 /* Operand 0 is a pointer-to-function; get the type of the function. */
899 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
900 if (TREE_CODE (funtype) != POINTER_TYPE)
902 funtype = TREE_TYPE (funtype);
904 /* Push the temporary stack slot level so that we can free any temporaries
908 /* Start updating where the next arg would go. */
909 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX);
911 /* If struct_value_rtx is 0, it means pass the address
912 as if it were an extra parameter. */
913 if (structure_value_addr && struct_value_rtx == 0)
915 /* If structure_value_addr is a REG other than
916 virtual_outgoing_args_rtx, we can use always use it. If it
917 is not a REG, we must always copy it into a register.
918 If it is virtual_outgoing_args_rtx, we must copy it to another
919 register in some cases. */
920 rtx temp = (GET_CODE (structure_value_addr) != REG
921 #ifdef ACCUMULATE_OUTGOING_ARGS
922 || (stack_arg_under_construction
923 && structure_value_addr == virtual_outgoing_args_rtx)
925 ? copy_addr_to_reg (structure_value_addr)
926 : structure_value_addr);
929 = tree_cons (error_mark_node,
930 make_tree (build_pointer_type (TREE_TYPE (funtype)),
933 structure_value_addr_parm = 1;
936 /* Count the arguments and set NUM_ACTUALS. */
937 for (p = actparms, i = 0; p; p = TREE_CHAIN (p)) i++;
940 /* Compute number of named args.
941 Normally, don't include the last named arg if anonymous args follow.
942 We do include the last named arg if STRICT_ARGUMENT_NAMING is defined.
943 (If no anonymous args follow, the result of list_length is actually
944 one too large. This is harmless.)
946 If SETUP_INCOMING_VARARGS is defined and STRICT_ARGUMENT_NAMING is not,
947 this machine will be able to place unnamed args that were passed in
948 registers into the stack. So treat all args as named. This allows the
949 insns emitting for a specific argument list to be independent of the
950 function declaration.
952 If SETUP_INCOMING_VARARGS is not defined, we do not have any reliable
953 way to pass unnamed args in registers, so we must force them into
955 #if !defined(SETUP_INCOMING_VARARGS) || defined(STRICT_ARGUMENT_NAMING)
956 if (TYPE_ARG_TYPES (funtype) != 0)
958 = (list_length (TYPE_ARG_TYPES (funtype))
959 #ifndef STRICT_ARGUMENT_NAMING
960 /* Don't include the last named arg. */
963 /* Count the struct value address, if it is passed as a parm. */
964 + structure_value_addr_parm);
967 /* If we know nothing, treat all args as named. */
968 n_named_args = num_actuals;
970 /* Make a vector to hold all the information about each arg. */
971 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
972 bzero ((char *) args, num_actuals * sizeof (struct arg_data));
974 args_size.constant = 0;
977 /* In this loop, we consider args in the order they are written.
978 We fill up ARGS from the front or from the back if necessary
979 so that in any case the first arg to be pushed ends up at the front. */
981 #ifdef PUSH_ARGS_REVERSED
982 i = num_actuals - 1, inc = -1;
983 /* In this case, must reverse order of args
984 so that we compute and push the last arg first. */
989 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
990 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
992 tree type = TREE_TYPE (TREE_VALUE (p));
994 enum machine_mode mode;
996 args[i].tree_value = TREE_VALUE (p);
998 /* Replace erroneous argument with constant zero. */
999 if (type == error_mark_node || TYPE_SIZE (type) == 0)
1000 args[i].tree_value = integer_zero_node, type = integer_type_node;
1002 /* If TYPE is a transparent union, pass things the way we would
1003 pass the first field of the union. We have already verified that
1004 the modes are the same. */
1005 if (TYPE_TRANSPARENT_UNION (type))
1006 type = TREE_TYPE (TYPE_FIELDS (type));
1008 /* Decide where to pass this arg.
1010 args[i].reg is nonzero if all or part is passed in registers.
1012 args[i].partial is nonzero if part but not all is passed in registers,
1013 and the exact value says how many words are passed in registers.
1015 args[i].pass_on_stack is nonzero if the argument must at least be
1016 computed on the stack. It may then be loaded back into registers
1017 if args[i].reg is nonzero.
1019 These decisions are driven by the FUNCTION_... macros and must agree
1020 with those made by function.c. */
1022 /* See if this argument should be passed by invisible reference. */
1023 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1024 && contains_placeholder_p (TYPE_SIZE (type)))
1025 || TYPE_NEEDS_CONSTRUCTING (type)
1026 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1027 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, TYPE_MODE (type),
1028 type, argpos < n_named_args)
1032 #ifdef FUNCTION_ARG_CALLEE_COPIES
1033 if (FUNCTION_ARG_CALLEE_COPIES (args_so_far, TYPE_MODE (type), type,
1034 argpos < n_named_args)
1035 /* If it's in a register, we must make a copy of it too. */
1036 /* ??? Is this a sufficient test? Is there a better one? */
1037 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1038 && REG_P (DECL_RTL (args[i].tree_value))))
1040 args[i].tree_value = build1 (ADDR_EXPR,
1041 build_pointer_type (type),
1042 args[i].tree_value);
1043 type = build_pointer_type (type);
1048 /* We make a copy of the object and pass the address to the
1049 function being called. */
1052 if (TYPE_SIZE (type) == 0
1053 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
1055 /* This is a variable-sized object. Make space on the stack
1057 rtx size_rtx = expr_size (TREE_VALUE (p));
1059 if (old_stack_level == 0)
1061 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1062 old_pending_adj = pending_stack_adjust;
1063 pending_stack_adjust = 0;
1066 copy = gen_rtx (MEM, BLKmode,
1067 allocate_dynamic_stack_space (size_rtx,
1069 TYPE_ALIGN (type)));
1073 int size = int_size_in_bytes (type);
1074 copy = assign_stack_temp (TYPE_MODE (type), size, 0);
1077 MEM_IN_STRUCT_P (copy) = AGGREGATE_TYPE_P (type);
1079 store_expr (args[i].tree_value, copy, 0);
1081 args[i].tree_value = build1 (ADDR_EXPR,
1082 build_pointer_type (type),
1083 make_tree (type, copy));
1084 type = build_pointer_type (type);
1088 mode = TYPE_MODE (type);
1089 unsignedp = TREE_UNSIGNED (type);
1091 #ifdef PROMOTE_FUNCTION_ARGS
1092 mode = promote_mode (type, mode, &unsignedp, 1);
1095 args[i].unsignedp = unsignedp;
1096 args[i].mode = mode;
1097 args[i].reg = FUNCTION_ARG (args_so_far, mode, type,
1098 argpos < n_named_args);
1099 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1102 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, type,
1103 argpos < n_named_args);
1106 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1108 /* If FUNCTION_ARG returned an (expr_list (nil) FOO), it means that
1109 we are to pass this arg in the register(s) designated by FOO, but
1110 also to pass it in the stack. */
1111 if (args[i].reg && GET_CODE (args[i].reg) == EXPR_LIST
1112 && XEXP (args[i].reg, 0) == 0)
1113 args[i].pass_on_stack = 1, args[i].reg = XEXP (args[i].reg, 1);
1115 /* If this is an addressable type, we must preallocate the stack
1116 since we must evaluate the object into its final location.
1118 If this is to be passed in both registers and the stack, it is simpler
1120 if (TREE_ADDRESSABLE (type)
1121 || (args[i].pass_on_stack && args[i].reg != 0))
1122 must_preallocate = 1;
1124 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1125 we cannot consider this function call constant. */
1126 if (TREE_ADDRESSABLE (type))
1129 /* Compute the stack-size of this argument. */
1130 if (args[i].reg == 0 || args[i].partial != 0
1131 #ifdef REG_PARM_STACK_SPACE
1132 || reg_parm_stack_space > 0
1134 || args[i].pass_on_stack)
1135 locate_and_pad_parm (mode, type,
1136 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1141 fndecl, &args_size, &args[i].offset,
1144 #ifndef ARGS_GROW_DOWNWARD
1145 args[i].slot_offset = args_size;
1148 #ifndef REG_PARM_STACK_SPACE
1149 /* If a part of the arg was put into registers,
1150 don't include that part in the amount pushed. */
1151 if (! args[i].pass_on_stack)
1152 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1153 / (PARM_BOUNDARY / BITS_PER_UNIT)
1154 * (PARM_BOUNDARY / BITS_PER_UNIT));
1157 /* Update ARGS_SIZE, the total stack space for args so far. */
1159 args_size.constant += args[i].size.constant;
1160 if (args[i].size.var)
1162 ADD_PARM_SIZE (args_size, args[i].size.var);
1165 /* Since the slot offset points to the bottom of the slot,
1166 we must record it after incrementing if the args grow down. */
1167 #ifdef ARGS_GROW_DOWNWARD
1168 args[i].slot_offset = args_size;
1170 args[i].slot_offset.constant = -args_size.constant;
1173 SUB_PARM_SIZE (args[i].slot_offset, args_size.var);
1177 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1178 have been used, etc. */
1180 FUNCTION_ARG_ADVANCE (args_so_far, TYPE_MODE (type), type,
1181 argpos < n_named_args);
1184 #ifdef FINAL_REG_PARM_STACK_SPACE
1185 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
1189 /* Compute the actual size of the argument block required. The variable
1190 and constant sizes must be combined, the size may have to be rounded,
1191 and there may be a minimum required size. */
1193 original_args_size = args_size;
1196 /* If this function requires a variable-sized argument list, don't try to
1197 make a cse'able block for this call. We may be able to do this
1198 eventually, but it is too complicated to keep track of what insns go
1199 in the cse'able block and which don't. */
1202 must_preallocate = 1;
1204 args_size.var = ARGS_SIZE_TREE (args_size);
1205 args_size.constant = 0;
1207 #ifdef STACK_BOUNDARY
1208 if (STACK_BOUNDARY != BITS_PER_UNIT)
1209 args_size.var = round_up (args_size.var, STACK_BYTES);
1212 #ifdef REG_PARM_STACK_SPACE
1213 if (reg_parm_stack_space > 0)
1216 = size_binop (MAX_EXPR, args_size.var,
1217 size_int (REG_PARM_STACK_SPACE (fndecl)));
1219 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1220 /* The area corresponding to register parameters is not to count in
1221 the size of the block we need. So make the adjustment. */
1223 = size_binop (MINUS_EXPR, args_size.var,
1224 size_int (reg_parm_stack_space));
1231 #ifdef STACK_BOUNDARY
1232 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
1233 / STACK_BYTES) * STACK_BYTES);
1236 #ifdef REG_PARM_STACK_SPACE
1237 args_size.constant = MAX (args_size.constant,
1238 reg_parm_stack_space);
1239 #ifdef MAYBE_REG_PARM_STACK_SPACE
1240 if (reg_parm_stack_space == 0)
1241 args_size.constant = 0;
1243 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1244 args_size.constant -= reg_parm_stack_space;
1249 /* See if we have or want to preallocate stack space.
1251 If we would have to push a partially-in-regs parm
1252 before other stack parms, preallocate stack space instead.
1254 If the size of some parm is not a multiple of the required stack
1255 alignment, we must preallocate.
1257 If the total size of arguments that would otherwise create a copy in
1258 a temporary (such as a CALL) is more than half the total argument list
1259 size, preallocation is faster.
1261 Another reason to preallocate is if we have a machine (like the m88k)
1262 where stack alignment is required to be maintained between every
1263 pair of insns, not just when the call is made. However, we assume here
1264 that such machines either do not have push insns (and hence preallocation
1265 would occur anyway) or the problem is taken care of with
1268 if (! must_preallocate)
1270 int partial_seen = 0;
1271 int copy_to_evaluate_size = 0;
1273 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1275 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1277 else if (partial_seen && args[i].reg == 0)
1278 must_preallocate = 1;
1280 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1281 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1282 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1283 || TREE_CODE (args[i].tree_value) == COND_EXPR
1284 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1285 copy_to_evaluate_size
1286 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1289 if (copy_to_evaluate_size * 2 >= args_size.constant
1290 && args_size.constant > 0)
1291 must_preallocate = 1;
1294 /* If the structure value address will reference the stack pointer, we must
1295 stabilize it. We don't need to do this if we know that we are not going
1296 to adjust the stack pointer in processing this call. */
1298 if (structure_value_addr
1299 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
1300 || reg_mentioned_p (virtual_outgoing_args_rtx, structure_value_addr))
1302 #ifndef ACCUMULATE_OUTGOING_ARGS
1303 || args_size.constant
1306 structure_value_addr = copy_to_reg (structure_value_addr);
1308 /* If this function call is cse'able, precompute all the parameters.
1309 Note that if the parameter is constructed into a temporary, this will
1310 cause an additional copy because the parameter will be constructed
1311 into a temporary location and then copied into the outgoing arguments.
1312 If a parameter contains a call to alloca and this function uses the
1313 stack, precompute the parameter. */
1315 /* If we preallocated the stack space, and some arguments must be passed
1316 on the stack, then we must precompute any parameter which contains a
1317 function call which will store arguments on the stack.
1318 Otherwise, evaluating the parameter may clobber previous parameters
1319 which have already been stored into the stack. */
1321 for (i = 0; i < num_actuals; i++)
1323 || ((args_size.var != 0 || args_size.constant != 0)
1324 && calls_function (args[i].tree_value, 1))
1325 || (must_preallocate && (args_size.var != 0 || args_size.constant != 0)
1326 && calls_function (args[i].tree_value, 0)))
1330 args[i].initial_value = args[i].value
1331 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1333 preserve_temp_slots (args[i].value);
1336 /* ANSI doesn't require a sequence point here,
1337 but PCC has one, so this will avoid some problems. */
1340 args[i].initial_value = args[i].value
1341 = protect_from_queue (args[i].initial_value, 0);
1343 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) != args[i].mode)
1345 = convert_modes (args[i].mode,
1346 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1347 args[i].value, args[i].unsignedp);
1350 /* Now we are about to start emitting insns that can be deleted
1351 if a libcall is deleted. */
1355 /* If we have no actual push instructions, or shouldn't use them,
1356 make space for all args right now. */
1358 if (args_size.var != 0)
1360 if (old_stack_level == 0)
1362 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1363 old_pending_adj = pending_stack_adjust;
1364 pending_stack_adjust = 0;
1365 #ifdef ACCUMULATE_OUTGOING_ARGS
1366 /* stack_arg_under_construction says whether a stack arg is
1367 being constructed at the old stack level. Pushing the stack
1368 gets a clean outgoing argument block. */
1369 old_stack_arg_under_construction = stack_arg_under_construction;
1370 stack_arg_under_construction = 0;
1373 argblock = push_block (ARGS_SIZE_RTX (args_size), 0, 0);
1377 /* Note that we must go through the motions of allocating an argument
1378 block even if the size is zero because we may be storing args
1379 in the area reserved for register arguments, which may be part of
1382 int needed = args_size.constant;
1384 /* Store the maximum argument space used. It will be pushed by the
1385 prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow checking). */
1387 if (needed > current_function_outgoing_args_size)
1388 current_function_outgoing_args_size = needed;
1390 if (must_preallocate)
1392 #ifdef ACCUMULATE_OUTGOING_ARGS
1393 /* Since the stack pointer will never be pushed, it is possible for
1394 the evaluation of a parm to clobber something we have already
1395 written to the stack. Since most function calls on RISC machines
1396 do not use the stack, this is uncommon, but must work correctly.
1398 Therefore, we save any area of the stack that was already written
1399 and that we are using. Here we set up to do this by making a new
1400 stack usage map from the old one. The actual save will be done
1403 Another approach might be to try to reorder the argument
1404 evaluations to avoid this conflicting stack usage. */
1406 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1407 /* Since we will be writing into the entire argument area, the
1408 map must be allocated for its entire size, not just the part that
1409 is the responsibility of the caller. */
1410 needed += reg_parm_stack_space;
1413 #ifdef ARGS_GROW_DOWNWARD
1414 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
1417 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
1420 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
1422 if (initial_highest_arg_in_use)
1423 bcopy (initial_stack_usage_map, stack_usage_map,
1424 initial_highest_arg_in_use);
1426 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
1427 bzero (&stack_usage_map[initial_highest_arg_in_use],
1428 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
1431 /* The address of the outgoing argument list must not be copied to a
1432 register here, because argblock would be left pointing to the
1433 wrong place after the call to allocate_dynamic_stack_space below.
1436 argblock = virtual_outgoing_args_rtx;
1438 #else /* not ACCUMULATE_OUTGOING_ARGS */
1439 if (inhibit_defer_pop == 0)
1441 /* Try to reuse some or all of the pending_stack_adjust
1442 to get this space. Maybe we can avoid any pushing. */
1443 if (needed > pending_stack_adjust)
1445 needed -= pending_stack_adjust;
1446 pending_stack_adjust = 0;
1450 pending_stack_adjust -= needed;
1454 /* Special case this because overhead of `push_block' in this
1455 case is non-trivial. */
1457 argblock = virtual_outgoing_args_rtx;
1459 argblock = push_block (GEN_INT (needed), 0, 0);
1461 /* We only really need to call `copy_to_reg' in the case where push
1462 insns are going to be used to pass ARGBLOCK to a function
1463 call in ARGS. In that case, the stack pointer changes value
1464 from the allocation point to the call point, and hence
1465 the value of VIRTUAL_OUTGOING_ARGS_RTX changes as well.
1466 But might as well always do it. */
1467 argblock = copy_to_reg (argblock);
1468 #endif /* not ACCUMULATE_OUTGOING_ARGS */
1472 #ifdef ACCUMULATE_OUTGOING_ARGS
1473 /* The save/restore code in store_one_arg handles all cases except one:
1474 a constructor call (including a C function returning a BLKmode struct)
1475 to initialize an argument. */
1476 if (stack_arg_under_construction)
1478 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1479 rtx push_size = GEN_INT (reg_parm_stack_space + args_size.constant);
1481 rtx push_size = GEN_INT (args_size.constant);
1483 if (old_stack_level == 0)
1485 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1486 old_pending_adj = pending_stack_adjust;
1487 pending_stack_adjust = 0;
1488 /* stack_arg_under_construction says whether a stack arg is
1489 being constructed at the old stack level. Pushing the stack
1490 gets a clean outgoing argument block. */
1491 old_stack_arg_under_construction = stack_arg_under_construction;
1492 stack_arg_under_construction = 0;
1493 /* Make a new map for the new argument list. */
1494 stack_usage_map = (char *)alloca (highest_outgoing_arg_in_use);
1495 bzero (stack_usage_map, highest_outgoing_arg_in_use);
1496 highest_outgoing_arg_in_use = 0;
1498 allocate_dynamic_stack_space (push_size, NULL_RTX, BITS_PER_UNIT);
1500 /* If argument evaluation might modify the stack pointer, copy the
1501 address of the argument list to a register. */
1502 for (i = 0; i < num_actuals; i++)
1503 if (args[i].pass_on_stack)
1505 argblock = copy_addr_to_reg (argblock);
1511 /* If we preallocated stack space, compute the address of each argument.
1512 We need not ensure it is a valid memory address here; it will be
1513 validized when it is used. */
1516 rtx arg_reg = argblock;
1519 if (GET_CODE (argblock) == PLUS)
1520 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1522 for (i = 0; i < num_actuals; i++)
1524 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1525 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1528 /* Skip this parm if it will not be passed on the stack. */
1529 if (! args[i].pass_on_stack && args[i].reg != 0)
1532 if (GET_CODE (offset) == CONST_INT)
1533 addr = plus_constant (arg_reg, INTVAL (offset));
1535 addr = gen_rtx (PLUS, Pmode, arg_reg, offset);
1537 addr = plus_constant (addr, arg_offset);
1538 args[i].stack = gen_rtx (MEM, args[i].mode, addr);
1539 MEM_IN_STRUCT_P (args[i].stack)
1540 = AGGREGATE_TYPE_P (TREE_TYPE (args[i].tree_value));
1542 if (GET_CODE (slot_offset) == CONST_INT)
1543 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1545 addr = gen_rtx (PLUS, Pmode, arg_reg, slot_offset);
1547 addr = plus_constant (addr, arg_offset);
1548 args[i].stack_slot = gen_rtx (MEM, args[i].mode, addr);
1552 #ifdef PUSH_ARGS_REVERSED
1553 #ifdef STACK_BOUNDARY
1554 /* If we push args individually in reverse order, perform stack alignment
1555 before the first push (the last arg). */
1557 anti_adjust_stack (GEN_INT (args_size.constant
1558 - original_args_size.constant));
1562 /* Don't try to defer pops if preallocating, not even from the first arg,
1563 since ARGBLOCK probably refers to the SP. */
1567 /* Get the function to call, in the form of RTL. */
1570 /* If this is the first use of the function, see if we need to
1571 make an external definition for it. */
1572 if (! TREE_USED (fndecl))
1574 assemble_external (fndecl);
1575 TREE_USED (fndecl) = 1;
1578 /* Get a SYMBOL_REF rtx for the function address. */
1579 funexp = XEXP (DECL_RTL (fndecl), 0);
1582 /* Generate an rtx (probably a pseudo-register) for the address. */
1585 funexp = expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1586 pop_temp_slots (); /* FUNEXP can't be BLKmode */
1590 /* Figure out the register where the value, if any, will come back. */
1592 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
1593 && ! structure_value_addr)
1595 if (pcc_struct_value)
1596 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
1599 valreg = hard_function_value (TREE_TYPE (exp), fndecl);
1602 /* Precompute all register parameters. It isn't safe to compute anything
1603 once we have started filling any specific hard regs. */
1605 for (i = 0; i < num_actuals; i++)
1606 if (args[i].reg != 0 && ! args[i].pass_on_stack)
1610 if (args[i].value == 0)
1613 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
1615 preserve_temp_slots (args[i].value);
1618 /* ANSI doesn't require a sequence point here,
1619 but PCC has one, so this will avoid some problems. */
1623 /* If we are to promote the function arg to a wider mode,
1626 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
1628 = convert_modes (args[i].mode,
1629 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1630 args[i].value, args[i].unsignedp);
1632 /* If the value is expensive, and we are inside an appropriately
1633 short loop, put the value into a pseudo and then put the pseudo
1636 For small register classes, also do this if this call uses
1637 register parameters. This is to avoid reload conflicts while
1638 loading the parameters registers. */
1640 if ((! (GET_CODE (args[i].value) == REG
1641 || (GET_CODE (args[i].value) == SUBREG
1642 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
1643 && args[i].mode != BLKmode
1644 && rtx_cost (args[i].value, SET) > 2
1645 #ifdef SMALL_REGISTER_CLASSES
1646 && (reg_parm_seen || preserve_subexpressions_p ())
1648 && preserve_subexpressions_p ()
1651 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
1654 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
1655 /* The argument list is the property of the called routine and it
1656 may clobber it. If the fixed area has been used for previous
1657 parameters, we must save and restore it.
1659 Here we compute the boundary of the that needs to be saved, if any. */
1661 #ifdef ARGS_GROW_DOWNWARD
1662 for (i = 0; i < reg_parm_stack_space + 1; i++)
1664 for (i = 0; i < reg_parm_stack_space; i++)
1667 if (i >= highest_outgoing_arg_in_use
1668 || stack_usage_map[i] == 0)
1671 if (low_to_save == -1)
1677 if (low_to_save >= 0)
1679 int num_to_save = high_to_save - low_to_save + 1;
1680 enum machine_mode save_mode
1681 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
1684 /* If we don't have the required alignment, must do this in BLKmode. */
1685 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
1686 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
1687 save_mode = BLKmode;
1689 stack_area = gen_rtx (MEM, save_mode,
1690 memory_address (save_mode,
1692 #ifdef ARGS_GROW_DOWNWARD
1693 plus_constant (argblock,
1696 plus_constant (argblock,
1700 if (save_mode == BLKmode)
1702 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
1703 MEM_IN_STRUCT_P (save_area) = 0;
1704 emit_block_move (validize_mem (save_area), stack_area,
1705 GEN_INT (num_to_save),
1706 PARM_BOUNDARY / BITS_PER_UNIT);
1710 save_area = gen_reg_rtx (save_mode);
1711 emit_move_insn (save_area, stack_area);
1717 /* Now store (and compute if necessary) all non-register parms.
1718 These come before register parms, since they can require block-moves,
1719 which could clobber the registers used for register parms.
1720 Parms which have partial registers are not stored here,
1721 but we do preallocate space here if they want that. */
1723 for (i = 0; i < num_actuals; i++)
1724 if (args[i].reg == 0 || args[i].pass_on_stack)
1725 store_one_arg (&args[i], argblock, may_be_alloca,
1726 args_size.var != 0, fndecl, reg_parm_stack_space);
1728 #ifdef STRICT_ALIGNMENT
1729 /* If we have a parm that is passed in registers but not in memory
1730 and whose alignment does not permit a direct copy into registers,
1731 make a group of pseudos that correspond to each register that we
1734 for (i = 0; i < num_actuals; i++)
1735 if (args[i].reg != 0 && ! args[i].pass_on_stack
1736 && args[i].mode == BLKmode
1737 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1738 < MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1740 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1741 int big_endian_correction = 0;
1743 args[i].n_aligned_regs
1744 = args[i].partial ? args[i].partial
1745 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1747 args[i].aligned_regs = (rtx *) alloca (sizeof (rtx)
1748 * args[i].n_aligned_regs);
1750 /* Structures smaller than a word are aligned to the least signifcant
1751 byte (to the right). On a BYTES_BIG_ENDIAN machine, this means we
1752 must skip the empty high order bytes when calculating the bit
1754 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
1755 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1757 for (j = 0; j < args[i].n_aligned_regs; j++)
1759 rtx reg = gen_reg_rtx (word_mode);
1760 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1761 int bitsize = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
1764 args[i].aligned_regs[j] = reg;
1766 /* Clobber REG and move each partword into it. Ensure we don't
1767 go past the end of the structure. Note that the loop below
1768 works because we've already verified that padding
1769 and endianness are compatible. */
1771 emit_insn (gen_rtx (CLOBBER, VOIDmode, reg));
1774 bitpos < BITS_PER_WORD && bytes > 0;
1775 bitpos += bitsize, bytes -= bitsize / BITS_PER_UNIT)
1777 int xbitpos = bitpos + big_endian_correction;
1779 store_bit_field (reg, bitsize, xbitpos, word_mode,
1780 extract_bit_field (word, bitsize, bitpos, 1,
1781 NULL_RTX, word_mode,
1783 bitsize / BITS_PER_UNIT,
1785 bitsize / BITS_PER_UNIT, BITS_PER_WORD);
1791 /* Now store any partially-in-registers parm.
1792 This is the last place a block-move can happen. */
1794 for (i = 0; i < num_actuals; i++)
1795 if (args[i].partial != 0 && ! args[i].pass_on_stack)
1796 store_one_arg (&args[i], argblock, may_be_alloca,
1797 args_size.var != 0, fndecl, reg_parm_stack_space);
1799 #ifndef PUSH_ARGS_REVERSED
1800 #ifdef STACK_BOUNDARY
1801 /* If we pushed args in forward order, perform stack alignment
1802 after pushing the last arg. */
1804 anti_adjust_stack (GEN_INT (args_size.constant
1805 - original_args_size.constant));
1809 /* If register arguments require space on the stack and stack space
1810 was not preallocated, allocate stack space here for arguments
1811 passed in registers. */
1812 #if ! defined(ACCUMULATE_OUTGOING_ARGS) && defined(OUTGOING_REG_PARM_STACK_SPACE)
1813 if (must_preallocate == 0 && reg_parm_stack_space > 0)
1814 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
1817 /* Pass the function the address in which to return a structure value. */
1818 if (structure_value_addr && ! structure_value_addr_parm)
1820 emit_move_insn (struct_value_rtx,
1822 force_operand (structure_value_addr,
1824 if (GET_CODE (struct_value_rtx) == REG)
1825 use_reg (&call_fusage, struct_value_rtx);
1828 funexp = prepare_call_address (funexp, fndecl, &call_fusage, reg_parm_seen);
1830 /* Now do the register loads required for any wholly-register parms or any
1831 parms which are passed both on the stack and in a register. Their
1832 expressions were already evaluated.
1834 Mark all register-parms as living through the call, putting these USE
1835 insns in the CALL_INSN_FUNCTION_USAGE field. */
1837 for (i = 0; i < num_actuals; i++)
1839 rtx list = args[i].reg;
1840 int partial = args[i].partial;
1847 /* Process each register that needs to get this arg. */
1848 if (GET_CODE (list) == EXPR_LIST)
1849 reg = XEXP (list, 0), list = XEXP (list, 1);
1851 reg = list, list = 0;
1853 /* Set to non-negative if must move a word at a time, even if just
1854 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1855 we just use a normal move insn. This value can be zero if the
1856 argument is a zero size structure with no fields. */
1857 nregs = (partial ? partial
1858 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1859 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1860 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1863 /* If simple case, just do move. If normal partial, store_one_arg
1864 has already loaded the register for us. In all other cases,
1865 load the register(s) from memory. */
1868 emit_move_insn (reg, args[i].value);
1870 #ifdef STRICT_ALIGNMENT
1871 /* If we have pre-computed the values to put in the registers in
1872 the case of non-aligned structures, copy them in now. */
1874 else if (args[i].n_aligned_regs != 0)
1875 for (j = 0; j < args[i].n_aligned_regs; j++)
1876 emit_move_insn (gen_rtx (REG, word_mode, REGNO (reg) + j),
1877 args[i].aligned_regs[j]);
1880 else if (args[i].partial == 0 || args[i].pass_on_stack)
1881 move_block_to_reg (REGNO (reg),
1882 validize_mem (args[i].value), nregs,
1886 use_reg (&call_fusage, reg);
1888 use_regs (&call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1890 /* PARTIAL referred only to the first register, so clear it for the
1896 /* Perform postincrements before actually calling the function. */
1899 /* All arguments and registers used for the call must be set up by now! */
1901 /* Generate the actual call instruction. */
1902 emit_call_1 (funexp, fndecl, funtype, args_size.constant, struct_value_size,
1903 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
1904 valreg, old_inhibit_defer_pop, call_fusage, is_const);
1906 /* If call is cse'able, make appropriate pair of reg-notes around it.
1907 Test valreg so we don't crash; may safely ignore `const'
1908 if return type is void. */
1909 if (is_const && valreg != 0)
1912 rtx temp = gen_reg_rtx (GET_MODE (valreg));
1915 /* Construct an "equal form" for the value which mentions all the
1916 arguments in order as well as the function name. */
1917 #ifdef PUSH_ARGS_REVERSED
1918 for (i = 0; i < num_actuals; i++)
1919 note = gen_rtx (EXPR_LIST, VOIDmode, args[i].initial_value, note);
1921 for (i = num_actuals - 1; i >= 0; i--)
1922 note = gen_rtx (EXPR_LIST, VOIDmode, args[i].initial_value, note);
1924 note = gen_rtx (EXPR_LIST, VOIDmode, funexp, note);
1926 insns = get_insns ();
1929 emit_libcall_block (insns, temp, valreg, note);
1935 /* Otherwise, just write out the sequence without a note. */
1936 rtx insns = get_insns ();
1942 /* For calls to `setjmp', etc., inform flow.c it should complain
1943 if nonvolatile values are live. */
1947 emit_note (name, NOTE_INSN_SETJMP);
1948 current_function_calls_setjmp = 1;
1952 current_function_calls_longjmp = 1;
1954 /* Notice functions that cannot return.
1955 If optimizing, insns emitted below will be dead.
1956 If not optimizing, they will exist, which is useful
1957 if the user uses the `return' command in the debugger. */
1959 if (is_volatile || is_longjmp)
1962 /* If value type not void, return an rtx for the value. */
1964 /* If there are cleanups to be called, don't use a hard reg as target. */
1965 if (cleanups_this_call != old_cleanups
1966 && target && REG_P (target)
1967 && REGNO (target) < FIRST_PSEUDO_REGISTER)
1970 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
1973 target = const0_rtx;
1975 else if (structure_value_addr)
1977 if (target == 0 || GET_CODE (target) != MEM)
1979 target = gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)),
1980 memory_address (TYPE_MODE (TREE_TYPE (exp)),
1981 structure_value_addr));
1982 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
1985 else if (pcc_struct_value)
1989 /* We used leave the value in the location that it is
1990 returned in, but that causes problems if it is used more
1991 than once in one expression. Rather than trying to track
1992 when a copy is required, we always copy when TARGET is
1993 not specified. This calling sequence is only used on
1994 a few machines and TARGET is usually nonzero. */
1995 if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
1997 target = assign_stack_temp (BLKmode,
1998 int_size_in_bytes (TREE_TYPE (exp)),
2001 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
2003 /* Save this temp slot around the pop below. */
2004 preserve_temp_slots (target);
2007 target = gen_reg_rtx (TYPE_MODE (TREE_TYPE (exp)));
2010 if (TYPE_MODE (TREE_TYPE (exp)) != BLKmode)
2011 emit_move_insn (target, gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)),
2012 copy_to_reg (valreg)));
2014 emit_block_move (target, gen_rtx (MEM, BLKmode, copy_to_reg (valreg)),
2016 TYPE_ALIGN (TREE_TYPE (exp)) / BITS_PER_UNIT);
2018 else if (target && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
2019 && GET_MODE (target) == GET_MODE (valreg))
2020 /* TARGET and VALREG cannot be equal at this point because the latter
2021 would not have REG_FUNCTION_VALUE_P true, while the former would if
2022 it were referring to the same register.
2024 If they refer to the same register, this move will be a no-op, except
2025 when function inlining is being done. */
2026 emit_move_insn (target, valreg);
2027 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
2029 /* Some machines (the PA for example) want to return all small
2030 structures in registers regardless of the structure's alignment.
2032 Deal with them explicitly by copying from the return registers
2033 into the target MEM locations. */
2034 int bytes = int_size_in_bytes (TREE_TYPE (exp));
2035 int n_regs = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
2037 enum machine_mode tmpmode;
2040 target = assign_stack_temp (BLKmode, bytes, 0);
2041 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
2043 /* We could probably emit more efficient code for machines
2044 which do not use strict alignment, but it doesn't seem
2045 worth the effort at the current time. */
2046 for (i = 0; i < n_regs; i++)
2048 rtx src = operand_subword_force (valreg, i, BLKmode);
2049 rtx dst = operand_subword (target, i, 1, BLKmode);
2050 int bitsize = MIN (TYPE_ALIGN (TREE_TYPE (exp)), BITS_PER_WORD);
2051 int bitpos, big_endian_correction = 0;
2053 /* Should never happen. */
2054 if (src == NULL || dst == NULL)
2057 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
2058 big_endian_correction
2059 = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
2062 bitpos < BITS_PER_WORD && bytes > 0;
2063 bitpos += bitsize, bytes -= bitsize / BITS_PER_UNIT)
2065 int xbitpos = bitpos + big_endian_correction;
2067 store_bit_field (dst, bitsize, xbitpos, word_mode,
2068 extract_bit_field (src, bitsize, bitpos, 1,
2069 NULL_RTX, word_mode,
2071 bitsize / BITS_PER_UNIT,
2073 bitsize / BITS_PER_UNIT, BITS_PER_WORD);
2078 target = copy_to_reg (valreg);
2080 #ifdef PROMOTE_FUNCTION_RETURN
2081 /* If we promoted this return value, make the proper SUBREG. TARGET
2082 might be const0_rtx here, so be careful. */
2083 if (GET_CODE (target) == REG
2084 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
2085 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
2087 tree type = TREE_TYPE (exp);
2088 int unsignedp = TREE_UNSIGNED (type);
2090 /* If we don't promote as expected, something is wrong. */
2091 if (GET_MODE (target)
2092 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
2095 target = gen_rtx (SUBREG, TYPE_MODE (type), target, 0);
2096 SUBREG_PROMOTED_VAR_P (target) = 1;
2097 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
2101 if (flag_short_temps)
2103 /* Perform all cleanups needed for the arguments of this call
2104 (i.e. destructors in C++). */
2105 expand_cleanups_to (old_cleanups);
2108 /* If size of args is variable or this was a constructor call for a stack
2109 argument, restore saved stack-pointer value. */
2111 if (old_stack_level)
2113 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
2114 pending_stack_adjust = old_pending_adj;
2115 #ifdef ACCUMULATE_OUTGOING_ARGS
2116 stack_arg_under_construction = old_stack_arg_under_construction;
2117 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2118 stack_usage_map = initial_stack_usage_map;
2121 #ifdef ACCUMULATE_OUTGOING_ARGS
2124 #ifdef REG_PARM_STACK_SPACE
2127 enum machine_mode save_mode = GET_MODE (save_area);
2129 = gen_rtx (MEM, save_mode,
2130 memory_address (save_mode,
2131 #ifdef ARGS_GROW_DOWNWARD
2132 plus_constant (argblock, - high_to_save)
2134 plus_constant (argblock, low_to_save)
2138 if (save_mode != BLKmode)
2139 emit_move_insn (stack_area, save_area);
2141 emit_block_move (stack_area, validize_mem (save_area),
2142 GEN_INT (high_to_save - low_to_save + 1),
2143 PARM_BOUNDARY / BITS_PER_UNIT);
2147 /* If we saved any argument areas, restore them. */
2148 for (i = 0; i < num_actuals; i++)
2149 if (args[i].save_area)
2151 enum machine_mode save_mode = GET_MODE (args[i].save_area);
2153 = gen_rtx (MEM, save_mode,
2154 memory_address (save_mode,
2155 XEXP (args[i].stack_slot, 0)));
2157 if (save_mode != BLKmode)
2158 emit_move_insn (stack_area, args[i].save_area);
2160 emit_block_move (stack_area, validize_mem (args[i].save_area),
2161 GEN_INT (args[i].size.constant),
2162 PARM_BOUNDARY / BITS_PER_UNIT);
2165 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2166 stack_usage_map = initial_stack_usage_map;
2170 /* If this was alloca, record the new stack level for nonlocal gotos.
2171 Check for the handler slots since we might not have a save area
2172 for non-local gotos. */
2174 if (may_be_alloca && nonlocal_goto_handler_slot != 0)
2175 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
2182 /* Output a library call to function FUN (a SYMBOL_REF rtx)
2183 (emitting the queue unless NO_QUEUE is nonzero),
2184 for a value of mode OUTMODE,
2185 with NARGS different arguments, passed as alternating rtx values
2186 and machine_modes to convert them to.
2187 The rtx values should have been passed through protect_from_queue already.
2189 NO_QUEUE will be true if and only if the library call is a `const' call
2190 which will be enclosed in REG_LIBCALL/REG_RETVAL notes; it is equivalent
2191 to the variable is_const in expand_call.
2193 NO_QUEUE must be true for const calls, because if it isn't, then
2194 any pending increment will be emitted between REG_LIBCALL/REG_RETVAL notes,
2195 and will be lost if the libcall sequence is optimized away.
2197 NO_QUEUE must be false for non-const calls, because if it isn't, the
2198 call insn will have its CONST_CALL_P bit set, and it will be incorrectly
2199 optimized. For instance, the instruction scheduler may incorrectly
2200 move memory references across the non-const call. */
2203 emit_library_call VPROTO((rtx orgfun, int no_queue, enum machine_mode outmode,
2209 enum machine_mode outmode;
2213 /* Total size in bytes of all the stack-parms scanned so far. */
2214 struct args_size args_size;
2215 /* Size of arguments before any adjustments (such as rounding). */
2216 struct args_size original_args_size;
2217 register int argnum;
2222 CUMULATIVE_ARGS args_so_far;
2223 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2224 struct args_size offset; struct args_size size; };
2226 int old_inhibit_defer_pop = inhibit_defer_pop;
2227 rtx call_fusage = 0;
2228 /* library calls are never indirect calls. */
2229 int current_call_is_indirect = 0;
2231 VA_START (p, nargs);
2234 orgfun = va_arg (p, rtx);
2235 no_queue = va_arg (p, int);
2236 outmode = va_arg (p, enum machine_mode);
2237 nargs = va_arg (p, int);
2242 /* Copy all the libcall-arguments out of the varargs data
2243 and into a vector ARGVEC.
2245 Compute how to pass each argument. We only support a very small subset
2246 of the full argument passing conventions to limit complexity here since
2247 library functions shouldn't have many args. */
2249 argvec = (struct arg *) alloca (nargs * sizeof (struct arg));
2251 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun);
2253 args_size.constant = 0;
2258 for (count = 0; count < nargs; count++)
2260 rtx val = va_arg (p, rtx);
2261 enum machine_mode mode = va_arg (p, enum machine_mode);
2263 /* We cannot convert the arg value to the mode the library wants here;
2264 must do it earlier where we know the signedness of the arg. */
2266 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2269 /* On some machines, there's no way to pass a float to a library fcn.
2270 Pass it as a double instead. */
2271 #ifdef LIBGCC_NEEDS_DOUBLE
2272 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2273 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
2276 /* There's no need to call protect_from_queue, because
2277 either emit_move_insn or emit_push_insn will do that. */
2279 /* Make sure it is a reasonable operand for a move or push insn. */
2280 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2281 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2282 val = force_operand (val, NULL_RTX);
2284 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2285 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2287 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2288 be viewed as just an efficiency improvement. */
2289 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2290 emit_move_insn (slot, val);
2291 val = force_operand (XEXP (slot, 0), NULL_RTX);
2296 argvec[count].value = val;
2297 argvec[count].mode = mode;
2299 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2300 if (argvec[count].reg && GET_CODE (argvec[count].reg) == EXPR_LIST)
2302 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2303 argvec[count].partial
2304 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2306 argvec[count].partial = 0;
2309 locate_and_pad_parm (mode, NULL_TREE,
2310 argvec[count].reg && argvec[count].partial == 0,
2311 NULL_TREE, &args_size, &argvec[count].offset,
2312 &argvec[count].size);
2314 if (argvec[count].size.var)
2317 #ifndef REG_PARM_STACK_SPACE
2318 if (argvec[count].partial)
2319 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2322 if (argvec[count].reg == 0 || argvec[count].partial != 0
2323 #ifdef REG_PARM_STACK_SPACE
2327 args_size.constant += argvec[count].size.constant;
2329 #ifdef ACCUMULATE_OUTGOING_ARGS
2330 /* If this arg is actually passed on the stack, it might be
2331 clobbering something we already put there (this library call might
2332 be inside the evaluation of an argument to a function whose call
2333 requires the stack). This will only occur when the library call
2334 has sufficient args to run out of argument registers. Abort in
2335 this case; if this ever occurs, code must be added to save and
2336 restore the arg slot. */
2338 if (argvec[count].reg == 0 || argvec[count].partial != 0)
2342 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree)0, 1);
2346 /* If this machine requires an external definition for library
2347 functions, write one out. */
2348 assemble_external_libcall (fun);
2350 original_args_size = args_size;
2351 #ifdef STACK_BOUNDARY
2352 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2353 / STACK_BYTES) * STACK_BYTES);
2356 #ifdef REG_PARM_STACK_SPACE
2357 args_size.constant = MAX (args_size.constant,
2358 REG_PARM_STACK_SPACE (NULL_TREE));
2359 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2360 args_size.constant -= REG_PARM_STACK_SPACE (NULL_TREE);
2364 if (args_size.constant > current_function_outgoing_args_size)
2365 current_function_outgoing_args_size = args_size.constant;
2367 #ifdef ACCUMULATE_OUTGOING_ARGS
2368 args_size.constant = 0;
2371 #ifndef PUSH_ROUNDING
2372 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2375 #ifdef PUSH_ARGS_REVERSED
2376 #ifdef STACK_BOUNDARY
2377 /* If we push args individually in reverse order, perform stack alignment
2378 before the first push (the last arg). */
2380 anti_adjust_stack (GEN_INT (args_size.constant
2381 - original_args_size.constant));
2385 #ifdef PUSH_ARGS_REVERSED
2393 /* Push the args that need to be pushed. */
2395 for (count = 0; count < nargs; count++, argnum += inc)
2397 register enum machine_mode mode = argvec[argnum].mode;
2398 register rtx val = argvec[argnum].value;
2399 rtx reg = argvec[argnum].reg;
2400 int partial = argvec[argnum].partial;
2402 if (! (reg != 0 && partial == 0))
2403 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2404 argblock, GEN_INT (argvec[count].offset.constant));
2408 #ifndef PUSH_ARGS_REVERSED
2409 #ifdef STACK_BOUNDARY
2410 /* If we pushed args in forward order, perform stack alignment
2411 after pushing the last arg. */
2413 anti_adjust_stack (GEN_INT (args_size.constant
2414 - original_args_size.constant));
2418 #ifdef PUSH_ARGS_REVERSED
2424 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
2426 /* Now load any reg parms into their regs. */
2428 for (count = 0; count < nargs; count++, argnum += inc)
2430 register enum machine_mode mode = argvec[argnum].mode;
2431 register rtx val = argvec[argnum].value;
2432 rtx reg = argvec[argnum].reg;
2433 int partial = argvec[argnum].partial;
2435 if (reg != 0 && partial == 0)
2436 emit_move_insn (reg, val);
2440 /* For version 1.37, try deleting this entirely. */
2444 /* Any regs containing parms remain in use through the call. */
2445 for (count = 0; count < nargs; count++)
2446 if (argvec[count].reg != 0)
2447 use_reg (&call_fusage, argvec[count].reg);
2449 /* Don't allow popping to be deferred, since then
2450 cse'ing of library calls could delete a call and leave the pop. */
2453 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2454 will set inhibit_defer_pop to that value. */
2457 get_identifier (XSTR (orgfun, 0)),
2458 get_identifier (XSTR (orgfun, 0)), args_size.constant, 0,
2459 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2460 outmode != VOIDmode ? hard_libcall_value (outmode) : NULL_RTX,
2461 old_inhibit_defer_pop + 1, call_fusage, no_queue);
2465 /* Now restore inhibit_defer_pop to its actual original value. */
2469 /* Like emit_library_call except that an extra argument, VALUE,
2470 comes second and says where to store the result.
2471 (If VALUE is zero, this function chooses a convenient way
2472 to return the value.
2474 This function returns an rtx for where the value is to be found.
2475 If VALUE is nonzero, VALUE is returned. */
2478 emit_library_call_value VPROTO((rtx orgfun, rtx value, int no_queue,
2479 enum machine_mode outmode, int nargs, ...))
2485 enum machine_mode outmode;
2489 /* Total size in bytes of all the stack-parms scanned so far. */
2490 struct args_size args_size;
2491 /* Size of arguments before any adjustments (such as rounding). */
2492 struct args_size original_args_size;
2493 register int argnum;
2498 CUMULATIVE_ARGS args_so_far;
2499 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2500 struct args_size offset; struct args_size size; };
2502 int old_inhibit_defer_pop = inhibit_defer_pop;
2503 rtx call_fusage = 0;
2505 int pcc_struct_value = 0;
2506 int struct_value_size = 0;
2507 /* library calls are never indirect calls. */
2508 int current_call_is_indirect = 0;
2511 VA_START (p, nargs);
2514 orgfun = va_arg (p, rtx);
2515 value = va_arg (p, rtx);
2516 no_queue = va_arg (p, int);
2517 outmode = va_arg (p, enum machine_mode);
2518 nargs = va_arg (p, int);
2521 is_const = no_queue;
2524 /* If this kind of value comes back in memory,
2525 decide where in memory it should come back. */
2526 if (aggregate_value_p (type_for_mode (outmode, 0)))
2528 #ifdef PCC_STATIC_STRUCT_RETURN
2530 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
2532 mem_value = gen_rtx (MEM, outmode, pointer_reg);
2533 pcc_struct_value = 1;
2535 value = gen_reg_rtx (outmode);
2536 #else /* not PCC_STATIC_STRUCT_RETURN */
2537 struct_value_size = GET_MODE_SIZE (outmode);
2538 if (value != 0 && GET_CODE (value) == MEM)
2541 mem_value = assign_stack_temp (outmode, GET_MODE_SIZE (outmode), 0);
2544 /* This call returns a big structure. */
2548 /* ??? Unfinished: must pass the memory address as an argument. */
2550 /* Copy all the libcall-arguments out of the varargs data
2551 and into a vector ARGVEC.
2553 Compute how to pass each argument. We only support a very small subset
2554 of the full argument passing conventions to limit complexity here since
2555 library functions shouldn't have many args. */
2557 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
2559 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun);
2561 args_size.constant = 0;
2568 /* If there's a structure value address to be passed,
2569 either pass it in the special place, or pass it as an extra argument. */
2570 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
2572 rtx addr = XEXP (mem_value, 0);
2575 /* Make sure it is a reasonable operand for a move or push insn. */
2576 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
2577 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
2578 addr = force_operand (addr, NULL_RTX);
2580 argvec[count].value = addr;
2581 argvec[count].mode = Pmode;
2582 argvec[count].partial = 0;
2584 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
2585 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2586 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
2590 locate_and_pad_parm (Pmode, NULL_TREE,
2591 argvec[count].reg && argvec[count].partial == 0,
2592 NULL_TREE, &args_size, &argvec[count].offset,
2593 &argvec[count].size);
2596 if (argvec[count].reg == 0 || argvec[count].partial != 0
2597 #ifdef REG_PARM_STACK_SPACE
2601 args_size.constant += argvec[count].size.constant;
2603 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree)0, 1);
2608 for (; count < nargs; count++)
2610 rtx val = va_arg (p, rtx);
2611 enum machine_mode mode = va_arg (p, enum machine_mode);
2613 /* We cannot convert the arg value to the mode the library wants here;
2614 must do it earlier where we know the signedness of the arg. */
2616 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2619 /* On some machines, there's no way to pass a float to a library fcn.
2620 Pass it as a double instead. */
2621 #ifdef LIBGCC_NEEDS_DOUBLE
2622 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2623 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
2626 /* There's no need to call protect_from_queue, because
2627 either emit_move_insn or emit_push_insn will do that. */
2629 /* Make sure it is a reasonable operand for a move or push insn. */
2630 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2631 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2632 val = force_operand (val, NULL_RTX);
2634 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2635 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2637 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2638 be viewed as just an efficiency improvement. */
2639 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2640 emit_move_insn (slot, val);
2641 val = XEXP (slot, 0);
2646 argvec[count].value = val;
2647 argvec[count].mode = mode;
2649 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2650 if (argvec[count].reg && GET_CODE (argvec[count].reg) == EXPR_LIST)
2652 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2653 argvec[count].partial
2654 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2656 argvec[count].partial = 0;
2659 locate_and_pad_parm (mode, NULL_TREE,
2660 argvec[count].reg && argvec[count].partial == 0,
2661 NULL_TREE, &args_size, &argvec[count].offset,
2662 &argvec[count].size);
2664 if (argvec[count].size.var)
2667 #ifndef REG_PARM_STACK_SPACE
2668 if (argvec[count].partial)
2669 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2672 if (argvec[count].reg == 0 || argvec[count].partial != 0
2673 #ifdef REG_PARM_STACK_SPACE
2677 args_size.constant += argvec[count].size.constant;
2679 #ifdef ACCUMULATE_OUTGOING_ARGS
2680 /* If this arg is actually passed on the stack, it might be
2681 clobbering something we already put there (this library call might
2682 be inside the evaluation of an argument to a function whose call
2683 requires the stack). This will only occur when the library call
2684 has sufficient args to run out of argument registers. Abort in
2685 this case; if this ever occurs, code must be added to save and
2686 restore the arg slot. */
2688 if (argvec[count].reg == 0 || argvec[count].partial != 0)
2692 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree)0, 1);
2696 /* If this machine requires an external definition for library
2697 functions, write one out. */
2698 assemble_external_libcall (fun);
2700 original_args_size = args_size;
2701 #ifdef STACK_BOUNDARY
2702 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2703 / STACK_BYTES) * STACK_BYTES);
2706 #ifdef REG_PARM_STACK_SPACE
2707 args_size.constant = MAX (args_size.constant,
2708 REG_PARM_STACK_SPACE (NULL_TREE));
2709 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2710 args_size.constant -= REG_PARM_STACK_SPACE (NULL_TREE);
2714 if (args_size.constant > current_function_outgoing_args_size)
2715 current_function_outgoing_args_size = args_size.constant;
2717 #ifdef ACCUMULATE_OUTGOING_ARGS
2718 args_size.constant = 0;
2721 #ifndef PUSH_ROUNDING
2722 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2725 #ifdef PUSH_ARGS_REVERSED
2726 #ifdef STACK_BOUNDARY
2727 /* If we push args individually in reverse order, perform stack alignment
2728 before the first push (the last arg). */
2730 anti_adjust_stack (GEN_INT (args_size.constant
2731 - original_args_size.constant));
2735 #ifdef PUSH_ARGS_REVERSED
2743 /* Push the args that need to be pushed. */
2745 for (count = 0; count < nargs; count++, argnum += inc)
2747 register enum machine_mode mode = argvec[argnum].mode;
2748 register rtx val = argvec[argnum].value;
2749 rtx reg = argvec[argnum].reg;
2750 int partial = argvec[argnum].partial;
2752 if (! (reg != 0 && partial == 0))
2753 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2754 argblock, GEN_INT (argvec[count].offset.constant));
2758 #ifndef PUSH_ARGS_REVERSED
2759 #ifdef STACK_BOUNDARY
2760 /* If we pushed args in forward order, perform stack alignment
2761 after pushing the last arg. */
2763 anti_adjust_stack (GEN_INT (args_size.constant
2764 - original_args_size.constant));
2768 #ifdef PUSH_ARGS_REVERSED
2774 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
2776 /* Now load any reg parms into their regs. */
2778 for (count = 0; count < nargs; count++, argnum += inc)
2780 register enum machine_mode mode = argvec[argnum].mode;
2781 register rtx val = argvec[argnum].value;
2782 rtx reg = argvec[argnum].reg;
2783 int partial = argvec[argnum].partial;
2785 if (reg != 0 && partial == 0)
2786 emit_move_insn (reg, val);
2791 /* For version 1.37, try deleting this entirely. */
2796 /* Any regs containing parms remain in use through the call. */
2797 for (count = 0; count < nargs; count++)
2798 if (argvec[count].reg != 0)
2799 use_reg (&call_fusage, argvec[count].reg);
2801 /* Pass the function the address in which to return a structure value. */
2802 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
2804 emit_move_insn (struct_value_rtx,
2806 force_operand (XEXP (mem_value, 0),
2808 if (GET_CODE (struct_value_rtx) == REG)
2809 use_reg (&call_fusage, struct_value_rtx);
2812 /* Don't allow popping to be deferred, since then
2813 cse'ing of library calls could delete a call and leave the pop. */
2816 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2817 will set inhibit_defer_pop to that value. */
2820 get_identifier (XSTR (orgfun, 0)),
2821 get_identifier (XSTR (orgfun, 0)), args_size.constant,
2823 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2824 (outmode != VOIDmode && mem_value == 0
2825 ? hard_libcall_value (outmode) : NULL_RTX),
2826 old_inhibit_defer_pop + 1, call_fusage, is_const);
2828 /* Now restore inhibit_defer_pop to its actual original value. */
2833 /* Copy the value to the right place. */
2834 if (outmode != VOIDmode)
2840 if (value != mem_value)
2841 emit_move_insn (value, mem_value);
2843 else if (value != 0)
2844 emit_move_insn (value, hard_libcall_value (outmode));
2846 value = hard_libcall_value (outmode);
2853 /* Return an rtx which represents a suitable home on the stack
2854 given TYPE, the type of the argument looking for a home.
2855 This is called only for BLKmode arguments.
2857 SIZE is the size needed for this target.
2858 ARGS_ADDR is the address of the bottom of the argument block for this call.
2859 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
2860 if this machine uses push insns. */
2863 target_for_arg (type, size, args_addr, offset)
2867 struct args_size offset;
2870 rtx offset_rtx = ARGS_SIZE_RTX (offset);
2872 /* We do not call memory_address if possible,
2873 because we want to address as close to the stack
2874 as possible. For non-variable sized arguments,
2875 this will be stack-pointer relative addressing. */
2876 if (GET_CODE (offset_rtx) == CONST_INT)
2877 target = plus_constant (args_addr, INTVAL (offset_rtx));
2880 /* I have no idea how to guarantee that this
2881 will work in the presence of register parameters. */
2882 target = gen_rtx (PLUS, Pmode, args_addr, offset_rtx);
2883 target = memory_address (QImode, target);
2886 return gen_rtx (MEM, BLKmode, target);
2890 /* Store a single argument for a function call
2891 into the register or memory area where it must be passed.
2892 *ARG describes the argument value and where to pass it.
2894 ARGBLOCK is the address of the stack-block for all the arguments,
2895 or 0 on a machine where arguments are pushed individually.
2897 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
2898 so must be careful about how the stack is used.
2900 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
2901 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
2902 that we need not worry about saving and restoring the stack.
2904 FNDECL is the declaration of the function we are calling. */
2907 store_one_arg (arg, argblock, may_be_alloca, variable_size, fndecl,
2908 reg_parm_stack_space)
2909 struct arg_data *arg;
2914 int reg_parm_stack_space;
2916 register tree pval = arg->tree_value;
2920 int i, lower_bound, upper_bound;
2922 if (TREE_CODE (pval) == ERROR_MARK)
2925 /* Push a new temporary level for any temporaries we make for
2929 #ifdef ACCUMULATE_OUTGOING_ARGS
2930 /* If this is being stored into a pre-allocated, fixed-size, stack area,
2931 save any previous data at that location. */
2932 if (argblock && ! variable_size && arg->stack)
2934 #ifdef ARGS_GROW_DOWNWARD
2935 /* stack_slot is negative, but we want to index stack_usage_map */
2936 /* with positive values. */
2937 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
2938 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
2942 lower_bound = upper_bound - arg->size.constant;
2944 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
2945 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
2949 upper_bound = lower_bound + arg->size.constant;
2952 for (i = lower_bound; i < upper_bound; i++)
2953 if (stack_usage_map[i]
2954 #ifdef REG_PARM_STACK_SPACE
2955 /* Don't store things in the fixed argument area at this point;
2956 it has already been saved. */
2957 && i > reg_parm_stack_space
2962 if (i != upper_bound)
2964 /* We need to make a save area. See what mode we can make it. */
2965 enum machine_mode save_mode
2966 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
2968 = gen_rtx (MEM, save_mode,
2969 memory_address (save_mode, XEXP (arg->stack_slot, 0)));
2971 if (save_mode == BLKmode)
2973 arg->save_area = assign_stack_temp (BLKmode,
2974 arg->size.constant, 0);
2975 MEM_IN_STRUCT_P (arg->save_area)
2976 = AGGREGATE_TYPE_P (TREE_TYPE (arg->tree_value));
2977 preserve_temp_slots (arg->save_area);
2978 emit_block_move (validize_mem (arg->save_area), stack_area,
2979 GEN_INT (arg->size.constant),
2980 PARM_BOUNDARY / BITS_PER_UNIT);
2984 arg->save_area = gen_reg_rtx (save_mode);
2985 emit_move_insn (arg->save_area, stack_area);
2991 /* If this isn't going to be placed on both the stack and in registers,
2992 set up the register and number of words. */
2993 if (! arg->pass_on_stack)
2994 reg = arg->reg, partial = arg->partial;
2996 if (reg != 0 && partial == 0)
2997 /* Being passed entirely in a register. We shouldn't be called in
3001 #ifdef STRICT_ALIGNMENT
3002 /* If this arg needs special alignment, don't load the registers
3004 if (arg->n_aligned_regs != 0)
3008 /* If this is being partially passed in a register, but multiple locations
3009 are specified, we assume that the one partially used is the one that is
3011 if (reg && GET_CODE (reg) == EXPR_LIST)
3012 reg = XEXP (reg, 0);
3014 /* If this is being passed partially in a register, we can't evaluate
3015 it directly into its stack slot. Otherwise, we can. */
3016 if (arg->value == 0)
3018 #ifdef ACCUMULATE_OUTGOING_ARGS
3019 /* stack_arg_under_construction is nonzero if a function argument is
3020 being evaluated directly into the outgoing argument list and
3021 expand_call must take special action to preserve the argument list
3022 if it is called recursively.
3024 For scalar function arguments stack_usage_map is sufficient to
3025 determine which stack slots must be saved and restored. Scalar
3026 arguments in general have pass_on_stack == 0.
3028 If this argument is initialized by a function which takes the
3029 address of the argument (a C++ constructor or a C function
3030 returning a BLKmode structure), then stack_usage_map is
3031 insufficient and expand_call must push the stack around the
3032 function call. Such arguments have pass_on_stack == 1.
3034 Note that it is always safe to set stack_arg_under_construction,
3035 but this generates suboptimal code if set when not needed. */
3037 if (arg->pass_on_stack)
3038 stack_arg_under_construction++;
3040 arg->value = expand_expr (pval,
3042 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
3043 ? NULL_RTX : arg->stack,
3046 /* If we are promoting object (or for any other reason) the mode
3047 doesn't agree, convert the mode. */
3049 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
3050 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
3051 arg->value, arg->unsignedp);
3053 #ifdef ACCUMULATE_OUTGOING_ARGS
3054 if (arg->pass_on_stack)
3055 stack_arg_under_construction--;
3059 /* Don't allow anything left on stack from computation
3060 of argument to alloca. */
3062 do_pending_stack_adjust ();
3064 if (arg->value == arg->stack)
3065 /* If the value is already in the stack slot, we are done. */
3067 else if (arg->mode != BLKmode)
3071 /* Argument is a scalar, not entirely passed in registers.
3072 (If part is passed in registers, arg->partial says how much
3073 and emit_push_insn will take care of putting it there.)
3075 Push it, and if its size is less than the
3076 amount of space allocated to it,
3077 also bump stack pointer by the additional space.
3078 Note that in C the default argument promotions
3079 will prevent such mismatches. */
3081 size = GET_MODE_SIZE (arg->mode);
3082 /* Compute how much space the push instruction will push.
3083 On many machines, pushing a byte will advance the stack
3084 pointer by a halfword. */
3085 #ifdef PUSH_ROUNDING
3086 size = PUSH_ROUNDING (size);
3090 /* Compute how much space the argument should get:
3091 round up to a multiple of the alignment for arguments. */
3092 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
3093 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
3094 / (PARM_BOUNDARY / BITS_PER_UNIT))
3095 * (PARM_BOUNDARY / BITS_PER_UNIT));
3097 /* This isn't already where we want it on the stack, so put it there.
3098 This can either be done with push or copy insns. */
3099 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
3100 0, partial, reg, used - size,
3101 argblock, ARGS_SIZE_RTX (arg->offset));
3105 /* BLKmode, at least partly to be pushed. */
3107 register int excess;
3110 /* Pushing a nonscalar.
3111 If part is passed in registers, PARTIAL says how much
3112 and emit_push_insn will take care of putting it there. */
3114 /* Round its size up to a multiple
3115 of the allocation unit for arguments. */
3117 if (arg->size.var != 0)
3120 size_rtx = ARGS_SIZE_RTX (arg->size);
3124 /* PUSH_ROUNDING has no effect on us, because
3125 emit_push_insn for BLKmode is careful to avoid it. */
3126 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
3127 + partial * UNITS_PER_WORD);
3128 size_rtx = expr_size (pval);
3131 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
3132 TYPE_ALIGN (TREE_TYPE (pval)) / BITS_PER_UNIT, partial,
3133 reg, excess, argblock, ARGS_SIZE_RTX (arg->offset));
3137 /* Unless this is a partially-in-register argument, the argument is now
3140 ??? Note that this can change arg->value from arg->stack to
3141 arg->stack_slot and it matters when they are not the same.
3142 It isn't totally clear that this is correct in all cases. */
3144 arg->value = arg->stack_slot;
3146 /* Once we have pushed something, pops can't safely
3147 be deferred during the rest of the arguments. */
3150 /* ANSI doesn't require a sequence point here,
3151 but PCC has one, so this will avoid some problems. */
3154 /* Free any temporary slots made in processing this argument. Show
3155 that we might have taken the address of something and pushed that
3157 preserve_temp_slots (NULL_RTX);
3161 #ifdef ACCUMULATE_OUTGOING_ARGS
3162 /* Now mark the segment we just used. */
3163 if (argblock && ! variable_size && arg->stack)
3164 for (i = lower_bound; i < upper_bound; i++)
3165 stack_usage_map[i] = 1;