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, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
31 #include "insn-flags.h"
33 /* Decide whether a function's arguments should be processed
34 from first to last or from last to first.
36 They should if the stack and args grow in opposite directions, but
37 only if we have push insns. */
41 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
42 #define PUSH_ARGS_REVERSED /* If it's last to first */
47 /* Like STACK_BOUNDARY but in units of bytes, not bits. */
48 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
50 /* Data structure and subroutines used within expand_call. */
54 /* Tree node for this argument. */
56 /* Mode for value; TYPE_MODE unless promoted. */
57 enum machine_mode mode;
58 /* Current RTL value for argument, or 0 if it isn't precomputed. */
60 /* Initially-compute RTL value for argument; only for const functions. */
62 /* Register to pass this argument in, 0 if passed on stack, or an
63 EXPR_LIST if the arg is to be copied into multiple different
66 /* If REG was promoted from the actual mode of the argument expression,
67 indicates whether the promotion is sign- or zero-extended. */
69 /* Number of registers to use. 0 means put the whole arg in registers.
70 Also 0 if not passed in registers. */
72 /* Non-zero if argument must be passed on stack.
73 Note that some arguments may be passed on the stack
74 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
75 pass_on_stack identifies arguments that *cannot* go in registers. */
77 /* Offset of this argument from beginning of stack-args. */
78 struct args_size offset;
79 /* Similar, but offset to the start of the stack slot. Different from
80 OFFSET if this arg pads downward. */
81 struct args_size slot_offset;
82 /* Size of this argument on the stack, rounded up for any padding it gets,
83 parts of the argument passed in registers do not count.
84 If REG_PARM_STACK_SPACE is defined, then register parms
85 are counted here as well. */
86 struct args_size size;
87 /* Location on the stack at which parameter should be stored. The store
88 has already been done if STACK == VALUE. */
90 /* Location on the stack of the start of this argument slot. This can
91 differ from STACK if this arg pads downward. This location is known
92 to be aligned to FUNCTION_ARG_BOUNDARY. */
94 #ifdef ACCUMULATE_OUTGOING_ARGS
95 /* Place that this stack area has been saved, if needed. */
98 #ifdef STRICT_ALIGNMENT
99 /* If an argument's alignment does not permit direct copying into registers,
100 copy in smaller-sized pieces into pseudos. These are stored in a
101 block pointed to by this field. The next field says how many
102 word-sized pseudos we made. */
108 #ifdef ACCUMULATE_OUTGOING_ARGS
109 /* A vector of one char per byte of stack space. A byte if non-zero if
110 the corresponding stack location has been used.
111 This vector is used to prevent a function call within an argument from
112 clobbering any stack already set up. */
113 static char *stack_usage_map;
115 /* Size of STACK_USAGE_MAP. */
116 static int highest_outgoing_arg_in_use;
118 /* stack_arg_under_construction is nonzero when an argument may be
119 initialized with a constructor call (including a C function that
120 returns a BLKmode struct) and expand_call must take special action
121 to make sure the object being constructed does not overlap the
122 argument list for the constructor call. */
123 int stack_arg_under_construction;
126 static int calls_function PROTO((tree, int));
127 static int calls_function_1 PROTO((tree, int));
128 static void emit_call_1 PROTO((rtx, tree, tree, int, int, rtx, rtx,
130 static void store_one_arg PROTO ((struct arg_data *, rtx, int, int,
133 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
136 If WHICH is 0, return 1 if EXP contains a call to any function.
137 Actually, we only need return 1 if evaluating EXP would require pushing
138 arguments on the stack, but that is too difficult to compute, so we just
139 assume any function call might require the stack. */
141 static tree calls_function_save_exprs;
144 calls_function (exp, which)
149 calls_function_save_exprs = 0;
150 val = calls_function_1 (exp, which);
151 calls_function_save_exprs = 0;
156 calls_function_1 (exp, which)
161 enum tree_code code = TREE_CODE (exp);
162 int type = TREE_CODE_CLASS (code);
163 int length = tree_code_length[(int) code];
165 /* If this code is language-specific, we don't know what it will do. */
166 if ((int) code >= NUM_TREE_CODES)
169 /* Only expressions and references can contain calls. */
170 if (type != 'e' && type != '<' && type != '1' && type != '2' && type != 'r'
179 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
180 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
183 tree fndecl = TREE_OPERAND (TREE_OPERAND (exp, 0), 0);
185 if ((DECL_BUILT_IN (fndecl)
186 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_ALLOCA)
187 || (DECL_SAVED_INSNS (fndecl)
188 && (FUNCTION_FLAGS (DECL_SAVED_INSNS (fndecl))
189 & FUNCTION_FLAGS_CALLS_ALLOCA)))
193 /* Third operand is RTL. */
198 if (SAVE_EXPR_RTL (exp) != 0)
200 if (value_member (exp, calls_function_save_exprs))
202 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
203 calls_function_save_exprs);
204 return (TREE_OPERAND (exp, 0) != 0
205 && calls_function_1 (TREE_OPERAND (exp, 0), which));
211 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
212 if (DECL_INITIAL (local) != 0
213 && calls_function_1 (DECL_INITIAL (local), which))
217 register tree subblock;
219 for (subblock = BLOCK_SUBBLOCKS (exp);
221 subblock = TREE_CHAIN (subblock))
222 if (calls_function_1 (subblock, which))
227 case METHOD_CALL_EXPR:
231 case WITH_CLEANUP_EXPR:
239 for (i = 0; i < length; i++)
240 if (TREE_OPERAND (exp, i) != 0
241 && calls_function_1 (TREE_OPERAND (exp, i), which))
247 /* Force FUNEXP into a form suitable for the address of a CALL,
248 and return that as an rtx. Also load the static chain register
249 if FNDECL is a nested function.
251 CALL_FUSAGE points to a variable holding the prospective
252 CALL_INSN_FUNCTION_USAGE information. */
255 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen)
261 rtx static_chain_value = 0;
263 funexp = protect_from_queue (funexp, 0);
266 /* Get possible static chain value for nested function in C. */
267 static_chain_value = lookup_static_chain (fndecl);
269 /* Make a valid memory address and copy constants thru pseudo-regs,
270 but not for a constant address if -fno-function-cse. */
271 if (GET_CODE (funexp) != SYMBOL_REF)
273 #ifdef SMALL_REGISTER_CLASSES
274 /* If we are using registers for parameters, force the
275 function address into a register now. */
276 reg_parm_seen ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
279 memory_address (FUNCTION_MODE, funexp);
282 #ifndef NO_FUNCTION_CSE
283 if (optimize && ! flag_no_function_cse)
284 #ifdef NO_RECURSIVE_FUNCTION_CSE
285 if (fndecl != current_function_decl)
287 funexp = force_reg (Pmode, funexp);
291 if (static_chain_value != 0)
293 emit_move_insn (static_chain_rtx, static_chain_value);
295 if (GET_CODE (static_chain_rtx) == REG)
296 use_reg (call_fusage, static_chain_rtx);
302 /* Generate instructions to call function FUNEXP,
303 and optionally pop the results.
304 The CALL_INSN is the first insn generated.
306 FNDECL is the declaration node of the function. This is given ot the
307 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
309 FUNTYPE is the data type of the function, or, for a library call,
310 the identifier for the name of the call. This is given to the
311 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
313 STACK_SIZE is the number of bytes of arguments on the stack,
314 rounded up to STACK_BOUNDARY; zero if the size is variable.
315 This is both to put into the call insn and
316 to generate explicit popping code if necessary.
318 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
319 It is zero if this call doesn't want a structure value.
321 NEXT_ARG_REG is the rtx that results from executing
322 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
323 just after all the args have had their registers assigned.
324 This could be whatever you like, but normally it is the first
325 arg-register beyond those used for args in this call,
326 or 0 if all the arg-registers are used in this call.
327 It is passed on to `gen_call' so you can put this info in the call insn.
329 VALREG is a hard register in which a value is returned,
330 or 0 if the call does not return a value.
332 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
333 the args to this call were processed.
334 We restore `inhibit_defer_pop' to that value.
336 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
337 denote registers used by the called function.
339 IS_CONST is true if this is a `const' call. */
342 emit_call_1 (funexp, fndecl, funtype, stack_size, struct_value_size,
343 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
349 int struct_value_size;
352 int old_inhibit_defer_pop;
356 rtx stack_size_rtx = GEN_INT (stack_size);
357 rtx struct_value_size_rtx = GEN_INT (struct_value_size);
359 int already_popped = 0;
361 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
362 and we don't want to load it into a register as an optimization,
363 because prepare_call_address already did it if it should be done. */
364 if (GET_CODE (funexp) != SYMBOL_REF)
365 funexp = memory_address (FUNCTION_MODE, funexp);
367 #ifndef ACCUMULATE_OUTGOING_ARGS
368 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
369 if (HAVE_call_pop && HAVE_call_value_pop
370 && (RETURN_POPS_ARGS (fndecl, funtype, stack_size) > 0
373 rtx n_pop = GEN_INT (RETURN_POPS_ARGS (fndecl, funtype, stack_size));
376 /* If this subroutine pops its own args, record that in the call insn
377 if possible, for the sake of frame pointer elimination. */
380 pat = gen_call_value_pop (valreg,
381 gen_rtx (MEM, FUNCTION_MODE, funexp),
382 stack_size_rtx, next_arg_reg, n_pop);
384 pat = gen_call_pop (gen_rtx (MEM, FUNCTION_MODE, funexp),
385 stack_size_rtx, next_arg_reg, n_pop);
387 emit_call_insn (pat);
394 #if defined (HAVE_call) && defined (HAVE_call_value)
395 if (HAVE_call && HAVE_call_value)
398 emit_call_insn (gen_call_value (valreg,
399 gen_rtx (MEM, FUNCTION_MODE, funexp),
400 stack_size_rtx, next_arg_reg,
403 emit_call_insn (gen_call (gen_rtx (MEM, FUNCTION_MODE, funexp),
404 stack_size_rtx, next_arg_reg,
405 struct_value_size_rtx));
411 /* Find the CALL insn we just emitted. */
412 for (call_insn = get_last_insn ();
413 call_insn && GET_CODE (call_insn) != CALL_INSN;
414 call_insn = PREV_INSN (call_insn))
420 /* Put the register usage information on the CALL. If there is already
421 some usage information, put ours at the end. */
422 if (CALL_INSN_FUNCTION_USAGE (call_insn))
426 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
427 link = XEXP (link, 1))
430 XEXP (link, 1) = call_fusage;
433 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
435 /* If this is a const call, then set the insn's unchanging bit. */
437 CONST_CALL_P (call_insn) = 1;
439 /* Restore this now, so that we do defer pops for this call's args
440 if the context of the call as a whole permits. */
441 inhibit_defer_pop = old_inhibit_defer_pop;
443 #ifndef ACCUMULATE_OUTGOING_ARGS
444 /* If returning from the subroutine does not automatically pop the args,
445 we need an instruction to pop them sooner or later.
446 Perhaps do it now; perhaps just record how much space to pop later.
448 If returning from the subroutine does pop the args, indicate that the
449 stack pointer will be changed. */
451 if (stack_size != 0 && RETURN_POPS_ARGS (fndecl, funtype, stack_size) > 0)
454 CALL_INSN_FUNCTION_USAGE (call_insn) =
455 gen_rtx (EXPR_LIST, VOIDmode,
456 gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx),
457 CALL_INSN_FUNCTION_USAGE (call_insn));
458 stack_size -= RETURN_POPS_ARGS (fndecl, funtype, stack_size);
459 stack_size_rtx = GEN_INT (stack_size);
464 if (flag_defer_pop && inhibit_defer_pop == 0 && !is_const)
465 pending_stack_adjust += stack_size;
467 adjust_stack (stack_size_rtx);
472 /* Generate all the code for a function call
473 and return an rtx for its value.
474 Store the value in TARGET (specified as an rtx) if convenient.
475 If the value is stored in TARGET then TARGET is returned.
476 If IGNORE is nonzero, then we ignore the value of the function call. */
479 expand_call (exp, target, ignore)
484 /* List of actual parameters. */
485 tree actparms = TREE_OPERAND (exp, 1);
486 /* RTX for the function to be called. */
488 /* Tree node for the function to be called (not the address!). */
490 /* Data type of the function. */
492 /* Declaration of the function being called,
493 or 0 if the function is computed (not known by name). */
497 /* Register in which non-BLKmode value will be returned,
498 or 0 if no value or if value is BLKmode. */
500 /* Address where we should return a BLKmode value;
501 0 if value not BLKmode. */
502 rtx structure_value_addr = 0;
503 /* Nonzero if that address is being passed by treating it as
504 an extra, implicit first parameter. Otherwise,
505 it is passed by being copied directly into struct_value_rtx. */
506 int structure_value_addr_parm = 0;
507 /* Size of aggregate value wanted, or zero if none wanted
508 or if we are using the non-reentrant PCC calling convention
509 or expecting the value in registers. */
510 int struct_value_size = 0;
511 /* Nonzero if called function returns an aggregate in memory PCC style,
512 by returning the address of where to find it. */
513 int pcc_struct_value = 0;
515 /* Number of actual parameters in this call, including struct value addr. */
517 /* Number of named args. Args after this are anonymous ones
518 and they must all go on the stack. */
520 /* Count arg position in order args appear. */
523 /* Vector of information about each argument.
524 Arguments are numbered in the order they will be pushed,
525 not the order they are written. */
526 struct arg_data *args;
528 /* Total size in bytes of all the stack-parms scanned so far. */
529 struct args_size args_size;
530 /* Size of arguments before any adjustments (such as rounding). */
531 struct args_size original_args_size;
532 /* Data on reg parms scanned so far. */
533 CUMULATIVE_ARGS args_so_far;
534 /* Nonzero if a reg parm has been scanned. */
536 /* Nonzero if this is an indirect function call. */
537 int current_call_is_indirect = 0;
539 /* Nonzero if we must avoid push-insns in the args for this call.
540 If stack space is allocated for register parameters, but not by the
541 caller, then it is preallocated in the fixed part of the stack frame.
542 So the entire argument block must then be preallocated (i.e., we
543 ignore PUSH_ROUNDING in that case). */
545 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
546 int must_preallocate = 1;
549 int must_preallocate = 0;
551 int must_preallocate = 1;
555 /* Size of the stack reserved for parameter registers. */
556 int reg_parm_stack_space = 0;
558 /* 1 if scanning parms front to back, -1 if scanning back to front. */
560 /* Address of space preallocated for stack parms
561 (on machines that lack push insns), or 0 if space not preallocated. */
564 /* Nonzero if it is plausible that this is a call to alloca. */
566 /* Nonzero if this is a call to setjmp or a related function. */
568 /* Nonzero if this is a call to `longjmp'. */
570 /* Nonzero if this is a call to an inline function. */
571 int is_integrable = 0;
572 /* Nonzero if this is a call to a `const' function.
573 Note that only explicitly named functions are handled as `const' here. */
575 /* Nonzero if this is a call to a `volatile' function. */
577 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
578 /* Define the boundary of the register parm stack space that needs to be
580 int low_to_save = -1, high_to_save;
581 rtx save_area = 0; /* Place that it is saved */
584 #ifdef ACCUMULATE_OUTGOING_ARGS
585 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
586 char *initial_stack_usage_map = stack_usage_map;
589 rtx old_stack_level = 0;
590 int old_pending_adj = 0;
591 int old_stack_arg_under_construction;
592 int old_inhibit_defer_pop = inhibit_defer_pop;
593 tree old_cleanups = cleanups_this_call;
598 /* See if we can find a DECL-node for the actual function.
599 As a result, decide whether this is a call to an integrable function. */
601 p = TREE_OPERAND (exp, 0);
602 if (TREE_CODE (p) == ADDR_EXPR)
604 fndecl = TREE_OPERAND (p, 0);
605 if (TREE_CODE (fndecl) != FUNCTION_DECL)
610 && fndecl != current_function_decl
611 && DECL_INLINE (fndecl)
612 && DECL_SAVED_INSNS (fndecl))
614 else if (! TREE_ADDRESSABLE (fndecl))
616 /* In case this function later becomes inlinable,
617 record that there was already a non-inline call to it.
619 Use abstraction instead of setting TREE_ADDRESSABLE
621 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline)
623 warning_with_decl (fndecl, "can't inline call to `%s'");
624 warning ("called from here");
626 mark_addressable (fndecl);
629 if (TREE_READONLY (fndecl) && ! TREE_THIS_VOLATILE (fndecl)
630 && TYPE_MODE (TREE_TYPE (exp)) != VOIDmode)
633 if (TREE_THIS_VOLATILE (fndecl))
638 /* If we don't have specific function to call, see if we have a
639 constant or `noreturn' function from the type. */
642 is_const = TREE_READONLY (TREE_TYPE (TREE_TYPE (p)));
643 is_volatile = TREE_THIS_VOLATILE (TREE_TYPE (TREE_TYPE (p)));
646 #ifdef REG_PARM_STACK_SPACE
647 #ifdef MAYBE_REG_PARM_STACK_SPACE
648 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
650 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
654 /* Warn if this value is an aggregate type,
655 regardless of which calling convention we are using for it. */
656 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
657 warning ("function call has aggregate value");
659 /* Set up a place to return a structure. */
661 /* Cater to broken compilers. */
662 if (aggregate_value_p (exp))
664 /* This call returns a big structure. */
667 #ifdef PCC_STATIC_STRUCT_RETURN
669 pcc_struct_value = 1;
670 /* Easier than making that case work right. */
673 /* In case this is a static function, note that it has been
675 if (! TREE_ADDRESSABLE (fndecl))
676 mark_addressable (fndecl);
680 #else /* not PCC_STATIC_STRUCT_RETURN */
682 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
684 if (target && GET_CODE (target) == MEM)
685 structure_value_addr = XEXP (target, 0);
688 /* Assign a temporary on the stack to hold the value. */
690 /* For variable-sized objects, we must be called with a target
691 specified. If we were to allocate space on the stack here,
692 we would have no way of knowing when to free it. */
694 if (struct_value_size < 0)
698 = XEXP (assign_stack_temp (BLKmode, struct_value_size, 1), 0);
699 MEM_IN_STRUCT_P (structure_value_addr)
700 = AGGREGATE_TYPE_P (TREE_TYPE (exp));
704 #endif /* not PCC_STATIC_STRUCT_RETURN */
707 /* If called function is inline, try to integrate it. */
712 rtx before_call = get_last_insn ();
714 temp = expand_inline_function (fndecl, actparms, target,
715 ignore, TREE_TYPE (exp),
716 structure_value_addr);
718 /* If inlining succeeded, return. */
719 if ((HOST_WIDE_INT) temp != -1)
721 if (flag_short_temps)
723 /* Perform all cleanups needed for the arguments of this
724 call (i.e. destructors in C++). It is ok if these
725 destructors clobber RETURN_VALUE_REG, because the
726 only time we care about this is when TARGET is that
727 register. But in C++, we take care to never return
728 that register directly. */
729 expand_cleanups_to (old_cleanups);
732 #ifdef ACCUMULATE_OUTGOING_ARGS
733 /* If the outgoing argument list must be preserved, push
734 the stack before executing the inlined function if it
737 for (i = reg_parm_stack_space - 1; i >= 0; i--)
738 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
741 if (stack_arg_under_construction || i >= 0)
743 rtx insn = NEXT_INSN (before_call), seq;
745 /* Look for a call in the inline function code.
746 If OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl)) is
747 nonzero then there is a call and it is not necessary
748 to scan the insns. */
750 if (OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl)) == 0)
751 for (; insn; insn = NEXT_INSN (insn))
752 if (GET_CODE (insn) == CALL_INSN)
757 /* Reserve enough stack space so that the largest
758 argument list of any function call in the inline
759 function does not overlap the argument list being
760 evaluated. This is usually an overestimate because
761 allocate_dynamic_stack_space reserves space for an
762 outgoing argument list in addition to the requested
763 space, but there is no way to ask for stack space such
764 that an argument list of a certain length can be
765 safely constructed. */
767 int adjust = OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl));
768 #ifdef REG_PARM_STACK_SPACE
769 /* Add the stack space reserved for register arguments
770 in the inline function. What is really needed is the
771 largest value of reg_parm_stack_space in the inline
772 function, but that is not available. Using the current
773 value of reg_parm_stack_space is wrong, but gives
774 correct results on all supported machines. */
775 adjust += reg_parm_stack_space;
778 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
779 allocate_dynamic_stack_space (GEN_INT (adjust),
780 NULL_RTX, BITS_PER_UNIT);
783 emit_insns_before (seq, NEXT_INSN (before_call));
784 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
789 /* If the result is equivalent to TARGET, return TARGET to simplify
790 checks in store_expr. They can be equivalent but not equal in the
791 case of a function that returns BLKmode. */
792 if (temp != target && rtx_equal_p (temp, target))
797 /* If inlining failed, mark FNDECL as needing to be compiled
798 separately after all. If function was declared inline,
800 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
801 && ! TREE_ADDRESSABLE (fndecl))
803 warning_with_decl (fndecl, "inlining failed in call to `%s'");
804 warning ("called from here");
806 mark_addressable (fndecl);
809 /* When calling a const function, we must pop the stack args right away,
810 so that the pop is deleted or moved with the call. */
814 function_call_count++;
816 if (fndecl && DECL_NAME (fndecl))
817 name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
819 /* On some machines (such as the PA) indirect calls have a different
820 calling convention than normal calls. FUNCTION_ARG in the target
821 description can look at current_call_is_indirect to determine which
822 calling convention to use. */
823 current_call_is_indirect = (fndecl == 0);
825 = TREE_CODE (TREE_OPERAND (exp, 0)) == NON_LVALUE_EXPR ? 1 : 0;
829 /* Unless it's a call to a specific function that isn't alloca,
830 if it has one argument, we must assume it might be alloca. */
833 (!(fndecl != 0 && strcmp (name, "alloca"))
835 && TREE_CHAIN (actparms) == 0);
837 /* We assume that alloca will always be called by name. It
838 makes no sense to pass it as a pointer-to-function to
839 anything that does not understand its behavior. */
841 (name && ((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
843 && ! strcmp (name, "alloca"))
844 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
846 && ! strcmp (name, "__builtin_alloca"))));
849 /* See if this is a call to a function that can return more than once
850 or a call to longjmp. */
855 if (name != 0 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 15)
859 /* Disregard prefix _, __ or __x. */
862 if (name[1] == '_' && name[2] == 'x')
864 else if (name[1] == '_')
874 && (! strcmp (tname, "setjmp")
875 || ! strcmp (tname, "setjmp_syscall")))
877 && ! strcmp (tname, "sigsetjmp"))
879 && ! strcmp (tname, "savectx")));
881 && ! strcmp (tname, "siglongjmp"))
884 else if ((tname[0] == 'q' && tname[1] == 's'
885 && ! strcmp (tname, "qsetjmp"))
886 || (tname[0] == 'v' && tname[1] == 'f'
887 && ! strcmp (tname, "vfork")))
890 else if (tname[0] == 'l' && tname[1] == 'o'
891 && ! strcmp (tname, "longjmp"))
896 current_function_calls_alloca = 1;
898 /* Don't let pending stack adjusts add up to too much.
899 Also, do all pending adjustments now
900 if there is any chance this might be a call to alloca. */
902 if (pending_stack_adjust >= 32
903 || (pending_stack_adjust > 0 && may_be_alloca))
904 do_pending_stack_adjust ();
906 /* Operand 0 is a pointer-to-function; get the type of the function. */
907 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
908 if (TREE_CODE (funtype) != POINTER_TYPE)
910 funtype = TREE_TYPE (funtype);
912 /* Push the temporary stack slot level so that we can free any temporaries
916 /* Start updating where the next arg would go. */
917 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX);
919 /* If struct_value_rtx is 0, it means pass the address
920 as if it were an extra parameter. */
921 if (structure_value_addr && struct_value_rtx == 0)
923 /* If structure_value_addr is a REG other than
924 virtual_outgoing_args_rtx, we can use always use it. If it
925 is not a REG, we must always copy it into a register.
926 If it is virtual_outgoing_args_rtx, we must copy it to another
927 register in some cases. */
928 rtx temp = (GET_CODE (structure_value_addr) != REG
929 #ifdef ACCUMULATE_OUTGOING_ARGS
930 || (stack_arg_under_construction
931 && structure_value_addr == virtual_outgoing_args_rtx)
933 ? copy_addr_to_reg (structure_value_addr)
934 : structure_value_addr);
937 = tree_cons (error_mark_node,
938 make_tree (build_pointer_type (TREE_TYPE (funtype)),
941 structure_value_addr_parm = 1;
944 /* Count the arguments and set NUM_ACTUALS. */
945 for (p = actparms, i = 0; p; p = TREE_CHAIN (p)) i++;
948 /* Compute number of named args.
949 Normally, don't include the last named arg if anonymous args follow.
950 We do include the last named arg if STRICT_ARGUMENT_NAMING is defined.
951 (If no anonymous args follow, the result of list_length is actually
952 one too large. This is harmless.)
954 If SETUP_INCOMING_VARARGS is defined and STRICT_ARGUMENT_NAMING is not,
955 this machine will be able to place unnamed args that were passed in
956 registers into the stack. So treat all args as named. This allows the
957 insns emitting for a specific argument list to be independent of the
958 function declaration.
960 If SETUP_INCOMING_VARARGS is not defined, we do not have any reliable
961 way to pass unnamed args in registers, so we must force them into
963 #if !defined(SETUP_INCOMING_VARARGS) || defined(STRICT_ARGUMENT_NAMING)
964 if (TYPE_ARG_TYPES (funtype) != 0)
966 = (list_length (TYPE_ARG_TYPES (funtype))
967 #ifndef STRICT_ARGUMENT_NAMING
968 /* Don't include the last named arg. */
971 /* Count the struct value address, if it is passed as a parm. */
972 + structure_value_addr_parm);
975 /* If we know nothing, treat all args as named. */
976 n_named_args = num_actuals;
978 /* Make a vector to hold all the information about each arg. */
979 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
980 bzero ((char *) args, num_actuals * sizeof (struct arg_data));
982 args_size.constant = 0;
985 /* In this loop, we consider args in the order they are written.
986 We fill up ARGS from the front or from the back if necessary
987 so that in any case the first arg to be pushed ends up at the front. */
989 #ifdef PUSH_ARGS_REVERSED
990 i = num_actuals - 1, inc = -1;
991 /* In this case, must reverse order of args
992 so that we compute and push the last arg first. */
997 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
998 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1000 tree type = TREE_TYPE (TREE_VALUE (p));
1002 enum machine_mode mode;
1004 args[i].tree_value = TREE_VALUE (p);
1006 /* Replace erroneous argument with constant zero. */
1007 if (type == error_mark_node || TYPE_SIZE (type) == 0)
1008 args[i].tree_value = integer_zero_node, type = integer_type_node;
1010 /* If TYPE is a transparent union, pass things the way we would
1011 pass the first field of the union. We have already verified that
1012 the modes are the same. */
1013 if (TYPE_TRANSPARENT_UNION (type))
1014 type = TREE_TYPE (TYPE_FIELDS (type));
1016 /* Decide where to pass this arg.
1018 args[i].reg is nonzero if all or part is passed in registers.
1020 args[i].partial is nonzero if part but not all is passed in registers,
1021 and the exact value says how many words are passed in registers.
1023 args[i].pass_on_stack is nonzero if the argument must at least be
1024 computed on the stack. It may then be loaded back into registers
1025 if args[i].reg is nonzero.
1027 These decisions are driven by the FUNCTION_... macros and must agree
1028 with those made by function.c. */
1030 /* See if this argument should be passed by invisible reference. */
1031 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1032 && contains_placeholder_p (TYPE_SIZE (type)))
1033 || TREE_ADDRESSABLE (type)
1034 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1035 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, TYPE_MODE (type),
1036 type, argpos < n_named_args)
1040 #ifdef FUNCTION_ARG_CALLEE_COPIES
1041 if (FUNCTION_ARG_CALLEE_COPIES (args_so_far, TYPE_MODE (type), type,
1042 argpos < n_named_args)
1043 /* If it's in a register, we must make a copy of it too. */
1044 /* ??? Is this a sufficient test? Is there a better one? */
1045 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1046 && REG_P (DECL_RTL (args[i].tree_value))))
1048 args[i].tree_value = build1 (ADDR_EXPR,
1049 build_pointer_type (type),
1050 args[i].tree_value);
1051 type = build_pointer_type (type);
1056 /* We make a copy of the object and pass the address to the
1057 function being called. */
1060 if (TYPE_SIZE (type) == 0
1061 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
1063 /* This is a variable-sized object. Make space on the stack
1065 rtx size_rtx = expr_size (TREE_VALUE (p));
1067 if (old_stack_level == 0)
1069 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1070 old_pending_adj = pending_stack_adjust;
1071 pending_stack_adjust = 0;
1074 copy = gen_rtx (MEM, BLKmode,
1075 allocate_dynamic_stack_space (size_rtx,
1077 TYPE_ALIGN (type)));
1081 int size = int_size_in_bytes (type);
1082 copy = assign_stack_temp (TYPE_MODE (type), size, 0);
1085 MEM_IN_STRUCT_P (copy) = AGGREGATE_TYPE_P (type);
1087 store_expr (args[i].tree_value, copy, 0);
1089 args[i].tree_value = build1 (ADDR_EXPR,
1090 build_pointer_type (type),
1091 make_tree (type, copy));
1092 type = build_pointer_type (type);
1096 mode = TYPE_MODE (type);
1097 unsignedp = TREE_UNSIGNED (type);
1099 #ifdef PROMOTE_FUNCTION_ARGS
1100 mode = promote_mode (type, mode, &unsignedp, 1);
1103 args[i].unsignedp = unsignedp;
1104 args[i].mode = mode;
1105 args[i].reg = FUNCTION_ARG (args_so_far, mode, type,
1106 argpos < n_named_args);
1107 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1110 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, type,
1111 argpos < n_named_args);
1114 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1116 /* If FUNCTION_ARG returned an (expr_list (nil) FOO), it means that
1117 we are to pass this arg in the register(s) designated by FOO, but
1118 also to pass it in the stack. */
1119 if (args[i].reg && GET_CODE (args[i].reg) == EXPR_LIST
1120 && XEXP (args[i].reg, 0) == 0)
1121 args[i].pass_on_stack = 1, args[i].reg = XEXP (args[i].reg, 1);
1123 /* If this is an addressable type, we must preallocate the stack
1124 since we must evaluate the object into its final location.
1126 If this is to be passed in both registers and the stack, it is simpler
1128 if (TREE_ADDRESSABLE (type)
1129 || (args[i].pass_on_stack && args[i].reg != 0))
1130 must_preallocate = 1;
1132 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1133 we cannot consider this function call constant. */
1134 if (TREE_ADDRESSABLE (type))
1137 /* Compute the stack-size of this argument. */
1138 if (args[i].reg == 0 || args[i].partial != 0
1139 #ifdef REG_PARM_STACK_SPACE
1140 || reg_parm_stack_space > 0
1142 || args[i].pass_on_stack)
1143 locate_and_pad_parm (mode, type,
1144 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1149 fndecl, &args_size, &args[i].offset,
1152 #ifndef ARGS_GROW_DOWNWARD
1153 args[i].slot_offset = args_size;
1156 #ifndef REG_PARM_STACK_SPACE
1157 /* If a part of the arg was put into registers,
1158 don't include that part in the amount pushed. */
1159 if (! args[i].pass_on_stack)
1160 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1161 / (PARM_BOUNDARY / BITS_PER_UNIT)
1162 * (PARM_BOUNDARY / BITS_PER_UNIT));
1165 /* Update ARGS_SIZE, the total stack space for args so far. */
1167 args_size.constant += args[i].size.constant;
1168 if (args[i].size.var)
1170 ADD_PARM_SIZE (args_size, args[i].size.var);
1173 /* Since the slot offset points to the bottom of the slot,
1174 we must record it after incrementing if the args grow down. */
1175 #ifdef ARGS_GROW_DOWNWARD
1176 args[i].slot_offset = args_size;
1178 args[i].slot_offset.constant = -args_size.constant;
1181 SUB_PARM_SIZE (args[i].slot_offset, args_size.var);
1185 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1186 have been used, etc. */
1188 FUNCTION_ARG_ADVANCE (args_so_far, TYPE_MODE (type), type,
1189 argpos < n_named_args);
1192 #ifdef FINAL_REG_PARM_STACK_SPACE
1193 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
1197 /* Compute the actual size of the argument block required. The variable
1198 and constant sizes must be combined, the size may have to be rounded,
1199 and there may be a minimum required size. */
1201 original_args_size = args_size;
1204 /* If this function requires a variable-sized argument list, don't try to
1205 make a cse'able block for this call. We may be able to do this
1206 eventually, but it is too complicated to keep track of what insns go
1207 in the cse'able block and which don't. */
1210 must_preallocate = 1;
1212 args_size.var = ARGS_SIZE_TREE (args_size);
1213 args_size.constant = 0;
1215 #ifdef STACK_BOUNDARY
1216 if (STACK_BOUNDARY != BITS_PER_UNIT)
1217 args_size.var = round_up (args_size.var, STACK_BYTES);
1220 #ifdef REG_PARM_STACK_SPACE
1221 if (reg_parm_stack_space > 0)
1224 = size_binop (MAX_EXPR, args_size.var,
1225 size_int (REG_PARM_STACK_SPACE (fndecl)));
1227 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1228 /* The area corresponding to register parameters is not to count in
1229 the size of the block we need. So make the adjustment. */
1231 = size_binop (MINUS_EXPR, args_size.var,
1232 size_int (reg_parm_stack_space));
1239 #ifdef STACK_BOUNDARY
1240 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
1241 / STACK_BYTES) * STACK_BYTES);
1244 #ifdef REG_PARM_STACK_SPACE
1245 args_size.constant = MAX (args_size.constant,
1246 reg_parm_stack_space);
1247 #ifdef MAYBE_REG_PARM_STACK_SPACE
1248 if (reg_parm_stack_space == 0)
1249 args_size.constant = 0;
1251 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1252 args_size.constant -= reg_parm_stack_space;
1257 /* See if we have or want to preallocate stack space.
1259 If we would have to push a partially-in-regs parm
1260 before other stack parms, preallocate stack space instead.
1262 If the size of some parm is not a multiple of the required stack
1263 alignment, we must preallocate.
1265 If the total size of arguments that would otherwise create a copy in
1266 a temporary (such as a CALL) is more than half the total argument list
1267 size, preallocation is faster.
1269 Another reason to preallocate is if we have a machine (like the m88k)
1270 where stack alignment is required to be maintained between every
1271 pair of insns, not just when the call is made. However, we assume here
1272 that such machines either do not have push insns (and hence preallocation
1273 would occur anyway) or the problem is taken care of with
1276 if (! must_preallocate)
1278 int partial_seen = 0;
1279 int copy_to_evaluate_size = 0;
1281 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1283 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1285 else if (partial_seen && args[i].reg == 0)
1286 must_preallocate = 1;
1288 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1289 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1290 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1291 || TREE_CODE (args[i].tree_value) == COND_EXPR
1292 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1293 copy_to_evaluate_size
1294 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1297 if (copy_to_evaluate_size * 2 >= args_size.constant
1298 && args_size.constant > 0)
1299 must_preallocate = 1;
1302 /* If the structure value address will reference the stack pointer, we must
1303 stabilize it. We don't need to do this if we know that we are not going
1304 to adjust the stack pointer in processing this call. */
1306 if (structure_value_addr
1307 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
1308 || reg_mentioned_p (virtual_outgoing_args_rtx, structure_value_addr))
1310 #ifndef ACCUMULATE_OUTGOING_ARGS
1311 || args_size.constant
1314 structure_value_addr = copy_to_reg (structure_value_addr);
1316 /* If this function call is cse'able, precompute all the parameters.
1317 Note that if the parameter is constructed into a temporary, this will
1318 cause an additional copy because the parameter will be constructed
1319 into a temporary location and then copied into the outgoing arguments.
1320 If a parameter contains a call to alloca and this function uses the
1321 stack, precompute the parameter. */
1323 /* If we preallocated the stack space, and some arguments must be passed
1324 on the stack, then we must precompute any parameter which contains a
1325 function call which will store arguments on the stack.
1326 Otherwise, evaluating the parameter may clobber previous parameters
1327 which have already been stored into the stack. */
1329 for (i = 0; i < num_actuals; i++)
1331 || ((args_size.var != 0 || args_size.constant != 0)
1332 && calls_function (args[i].tree_value, 1))
1333 || (must_preallocate && (args_size.var != 0 || args_size.constant != 0)
1334 && calls_function (args[i].tree_value, 0)))
1336 /* If this is an addressable type, we cannot pre-evaluate it. */
1337 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1342 args[i].initial_value = args[i].value
1343 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1345 preserve_temp_slots (args[i].value);
1348 /* ANSI doesn't require a sequence point here,
1349 but PCC has one, so this will avoid some problems. */
1352 args[i].initial_value = args[i].value
1353 = protect_from_queue (args[i].initial_value, 0);
1355 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) != args[i].mode)
1357 = convert_modes (args[i].mode,
1358 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1359 args[i].value, args[i].unsignedp);
1362 /* Now we are about to start emitting insns that can be deleted
1363 if a libcall is deleted. */
1367 /* If we have no actual push instructions, or shouldn't use them,
1368 make space for all args right now. */
1370 if (args_size.var != 0)
1372 if (old_stack_level == 0)
1374 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1375 old_pending_adj = pending_stack_adjust;
1376 pending_stack_adjust = 0;
1377 #ifdef ACCUMULATE_OUTGOING_ARGS
1378 /* stack_arg_under_construction says whether a stack arg is
1379 being constructed at the old stack level. Pushing the stack
1380 gets a clean outgoing argument block. */
1381 old_stack_arg_under_construction = stack_arg_under_construction;
1382 stack_arg_under_construction = 0;
1385 argblock = push_block (ARGS_SIZE_RTX (args_size), 0, 0);
1389 /* Note that we must go through the motions of allocating an argument
1390 block even if the size is zero because we may be storing args
1391 in the area reserved for register arguments, which may be part of
1394 int needed = args_size.constant;
1396 /* Store the maximum argument space used. It will be pushed by the
1397 prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow checking). */
1399 if (needed > current_function_outgoing_args_size)
1400 current_function_outgoing_args_size = needed;
1402 if (must_preallocate)
1404 #ifdef ACCUMULATE_OUTGOING_ARGS
1405 /* Since the stack pointer will never be pushed, it is possible for
1406 the evaluation of a parm to clobber something we have already
1407 written to the stack. Since most function calls on RISC machines
1408 do not use the stack, this is uncommon, but must work correctly.
1410 Therefore, we save any area of the stack that was already written
1411 and that we are using. Here we set up to do this by making a new
1412 stack usage map from the old one. The actual save will be done
1415 Another approach might be to try to reorder the argument
1416 evaluations to avoid this conflicting stack usage. */
1418 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1419 /* Since we will be writing into the entire argument area, the
1420 map must be allocated for its entire size, not just the part that
1421 is the responsibility of the caller. */
1422 needed += reg_parm_stack_space;
1425 #ifdef ARGS_GROW_DOWNWARD
1426 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
1429 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
1432 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
1434 if (initial_highest_arg_in_use)
1435 bcopy (initial_stack_usage_map, stack_usage_map,
1436 initial_highest_arg_in_use);
1438 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
1439 bzero (&stack_usage_map[initial_highest_arg_in_use],
1440 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
1443 /* The address of the outgoing argument list must not be copied to a
1444 register here, because argblock would be left pointing to the
1445 wrong place after the call to allocate_dynamic_stack_space below.
1448 argblock = virtual_outgoing_args_rtx;
1450 #else /* not ACCUMULATE_OUTGOING_ARGS */
1451 if (inhibit_defer_pop == 0)
1453 /* Try to reuse some or all of the pending_stack_adjust
1454 to get this space. Maybe we can avoid any pushing. */
1455 if (needed > pending_stack_adjust)
1457 needed -= pending_stack_adjust;
1458 pending_stack_adjust = 0;
1462 pending_stack_adjust -= needed;
1466 /* Special case this because overhead of `push_block' in this
1467 case is non-trivial. */
1469 argblock = virtual_outgoing_args_rtx;
1471 argblock = push_block (GEN_INT (needed), 0, 0);
1473 /* We only really need to call `copy_to_reg' in the case where push
1474 insns are going to be used to pass ARGBLOCK to a function
1475 call in ARGS. In that case, the stack pointer changes value
1476 from the allocation point to the call point, and hence
1477 the value of VIRTUAL_OUTGOING_ARGS_RTX changes as well.
1478 But might as well always do it. */
1479 argblock = copy_to_reg (argblock);
1480 #endif /* not ACCUMULATE_OUTGOING_ARGS */
1484 #ifdef ACCUMULATE_OUTGOING_ARGS
1485 /* The save/restore code in store_one_arg handles all cases except one:
1486 a constructor call (including a C function returning a BLKmode struct)
1487 to initialize an argument. */
1488 if (stack_arg_under_construction)
1490 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1491 rtx push_size = GEN_INT (reg_parm_stack_space + args_size.constant);
1493 rtx push_size = GEN_INT (args_size.constant);
1495 if (old_stack_level == 0)
1497 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1498 old_pending_adj = pending_stack_adjust;
1499 pending_stack_adjust = 0;
1500 /* stack_arg_under_construction says whether a stack arg is
1501 being constructed at the old stack level. Pushing the stack
1502 gets a clean outgoing argument block. */
1503 old_stack_arg_under_construction = stack_arg_under_construction;
1504 stack_arg_under_construction = 0;
1505 /* Make a new map for the new argument list. */
1506 stack_usage_map = (char *)alloca (highest_outgoing_arg_in_use);
1507 bzero (stack_usage_map, highest_outgoing_arg_in_use);
1508 highest_outgoing_arg_in_use = 0;
1510 allocate_dynamic_stack_space (push_size, NULL_RTX, BITS_PER_UNIT);
1512 /* If argument evaluation might modify the stack pointer, copy the
1513 address of the argument list to a register. */
1514 for (i = 0; i < num_actuals; i++)
1515 if (args[i].pass_on_stack)
1517 argblock = copy_addr_to_reg (argblock);
1523 /* If we preallocated stack space, compute the address of each argument.
1524 We need not ensure it is a valid memory address here; it will be
1525 validized when it is used. */
1528 rtx arg_reg = argblock;
1531 if (GET_CODE (argblock) == PLUS)
1532 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1534 for (i = 0; i < num_actuals; i++)
1536 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1537 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1540 /* Skip this parm if it will not be passed on the stack. */
1541 if (! args[i].pass_on_stack && args[i].reg != 0)
1544 if (GET_CODE (offset) == CONST_INT)
1545 addr = plus_constant (arg_reg, INTVAL (offset));
1547 addr = gen_rtx (PLUS, Pmode, arg_reg, offset);
1549 addr = plus_constant (addr, arg_offset);
1550 args[i].stack = gen_rtx (MEM, args[i].mode, addr);
1551 MEM_IN_STRUCT_P (args[i].stack)
1552 = AGGREGATE_TYPE_P (TREE_TYPE (args[i].tree_value));
1554 if (GET_CODE (slot_offset) == CONST_INT)
1555 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1557 addr = gen_rtx (PLUS, Pmode, arg_reg, slot_offset);
1559 addr = plus_constant (addr, arg_offset);
1560 args[i].stack_slot = gen_rtx (MEM, args[i].mode, addr);
1564 #ifdef PUSH_ARGS_REVERSED
1565 #ifdef STACK_BOUNDARY
1566 /* If we push args individually in reverse order, perform stack alignment
1567 before the first push (the last arg). */
1569 anti_adjust_stack (GEN_INT (args_size.constant
1570 - original_args_size.constant));
1574 /* Don't try to defer pops if preallocating, not even from the first arg,
1575 since ARGBLOCK probably refers to the SP. */
1579 /* Get the function to call, in the form of RTL. */
1582 /* If this is the first use of the function, see if we need to
1583 make an external definition for it. */
1584 if (! TREE_USED (fndecl))
1586 assemble_external (fndecl);
1587 TREE_USED (fndecl) = 1;
1590 /* Get a SYMBOL_REF rtx for the function address. */
1591 funexp = XEXP (DECL_RTL (fndecl), 0);
1594 /* Generate an rtx (probably a pseudo-register) for the address. */
1597 funexp = expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1598 pop_temp_slots (); /* FUNEXP can't be BLKmode */
1602 /* Figure out the register where the value, if any, will come back. */
1604 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
1605 && ! structure_value_addr)
1607 if (pcc_struct_value)
1608 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
1611 valreg = hard_function_value (TREE_TYPE (exp), fndecl);
1614 /* Precompute all register parameters. It isn't safe to compute anything
1615 once we have started filling any specific hard regs. */
1617 for (i = 0; i < num_actuals; i++)
1618 if (args[i].reg != 0 && ! args[i].pass_on_stack)
1622 if (args[i].value == 0)
1625 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
1627 preserve_temp_slots (args[i].value);
1630 /* ANSI doesn't require a sequence point here,
1631 but PCC has one, so this will avoid some problems. */
1635 /* If we are to promote the function arg to a wider mode,
1638 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
1640 = convert_modes (args[i].mode,
1641 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1642 args[i].value, args[i].unsignedp);
1644 /* If the value is expensive, and we are inside an appropriately
1645 short loop, put the value into a pseudo and then put the pseudo
1648 For small register classes, also do this if this call uses
1649 register parameters. This is to avoid reload conflicts while
1650 loading the parameters registers. */
1652 if ((! (GET_CODE (args[i].value) == REG
1653 || (GET_CODE (args[i].value) == SUBREG
1654 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
1655 && args[i].mode != BLKmode
1656 && rtx_cost (args[i].value, SET) > 2
1657 #ifdef SMALL_REGISTER_CLASSES
1658 && (reg_parm_seen || preserve_subexpressions_p ())
1660 && preserve_subexpressions_p ()
1663 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
1666 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
1667 /* The argument list is the property of the called routine and it
1668 may clobber it. If the fixed area has been used for previous
1669 parameters, we must save and restore it.
1671 Here we compute the boundary of the that needs to be saved, if any. */
1673 #ifdef ARGS_GROW_DOWNWARD
1674 for (i = 0; i < reg_parm_stack_space + 1; i++)
1676 for (i = 0; i < reg_parm_stack_space; i++)
1679 if (i >= highest_outgoing_arg_in_use
1680 || stack_usage_map[i] == 0)
1683 if (low_to_save == -1)
1689 if (low_to_save >= 0)
1691 int num_to_save = high_to_save - low_to_save + 1;
1692 enum machine_mode save_mode
1693 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
1696 /* If we don't have the required alignment, must do this in BLKmode. */
1697 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
1698 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
1699 save_mode = BLKmode;
1701 stack_area = gen_rtx (MEM, save_mode,
1702 memory_address (save_mode,
1704 #ifdef ARGS_GROW_DOWNWARD
1705 plus_constant (argblock,
1708 plus_constant (argblock,
1712 if (save_mode == BLKmode)
1714 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
1715 MEM_IN_STRUCT_P (save_area) = 0;
1716 emit_block_move (validize_mem (save_area), stack_area,
1717 GEN_INT (num_to_save),
1718 PARM_BOUNDARY / BITS_PER_UNIT);
1722 save_area = gen_reg_rtx (save_mode);
1723 emit_move_insn (save_area, stack_area);
1729 /* Now store (and compute if necessary) all non-register parms.
1730 These come before register parms, since they can require block-moves,
1731 which could clobber the registers used for register parms.
1732 Parms which have partial registers are not stored here,
1733 but we do preallocate space here if they want that. */
1735 for (i = 0; i < num_actuals; i++)
1736 if (args[i].reg == 0 || args[i].pass_on_stack)
1737 store_one_arg (&args[i], argblock, may_be_alloca,
1738 args_size.var != 0, fndecl, reg_parm_stack_space);
1740 #ifdef STRICT_ALIGNMENT
1741 /* If we have a parm that is passed in registers but not in memory
1742 and whose alignment does not permit a direct copy into registers,
1743 make a group of pseudos that correspond to each register that we
1746 for (i = 0; i < num_actuals; i++)
1747 if (args[i].reg != 0 && ! args[i].pass_on_stack
1748 && args[i].mode == BLKmode
1749 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1750 < MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1752 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1753 int big_endian_correction = 0;
1755 args[i].n_aligned_regs
1756 = args[i].partial ? args[i].partial
1757 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1759 args[i].aligned_regs = (rtx *) alloca (sizeof (rtx)
1760 * args[i].n_aligned_regs);
1762 /* Structures smaller than a word are aligned to the least significant
1763 byte (to the right). On a BYTES_BIG_ENDIAN machine, this means we
1764 must skip the empty high order bytes when calculating the bit
1766 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
1767 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1769 for (j = 0; j < args[i].n_aligned_regs; j++)
1771 rtx reg = gen_reg_rtx (word_mode);
1772 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1773 int bitsize = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
1776 args[i].aligned_regs[j] = reg;
1778 /* Clobber REG and move each partword into it. Ensure we don't
1779 go past the end of the structure. Note that the loop below
1780 works because we've already verified that padding
1781 and endianness are compatible. */
1783 emit_insn (gen_rtx (CLOBBER, VOIDmode, reg));
1786 bitpos < BITS_PER_WORD && bytes > 0;
1787 bitpos += bitsize, bytes -= bitsize / BITS_PER_UNIT)
1789 int xbitpos = bitpos + big_endian_correction;
1791 store_bit_field (reg, bitsize, xbitpos, word_mode,
1792 extract_bit_field (word, bitsize, bitpos, 1,
1793 NULL_RTX, word_mode,
1795 bitsize / BITS_PER_UNIT,
1797 bitsize / BITS_PER_UNIT, BITS_PER_WORD);
1803 /* Now store any partially-in-registers parm.
1804 This is the last place a block-move can happen. */
1806 for (i = 0; i < num_actuals; i++)
1807 if (args[i].partial != 0 && ! args[i].pass_on_stack)
1808 store_one_arg (&args[i], argblock, may_be_alloca,
1809 args_size.var != 0, fndecl, reg_parm_stack_space);
1811 #ifndef PUSH_ARGS_REVERSED
1812 #ifdef STACK_BOUNDARY
1813 /* If we pushed args in forward order, perform stack alignment
1814 after pushing the last arg. */
1816 anti_adjust_stack (GEN_INT (args_size.constant
1817 - original_args_size.constant));
1821 /* If register arguments require space on the stack and stack space
1822 was not preallocated, allocate stack space here for arguments
1823 passed in registers. */
1824 #if ! defined(ACCUMULATE_OUTGOING_ARGS) && defined(OUTGOING_REG_PARM_STACK_SPACE)
1825 if (must_preallocate == 0 && reg_parm_stack_space > 0)
1826 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
1829 /* Pass the function the address in which to return a structure value. */
1830 if (structure_value_addr && ! structure_value_addr_parm)
1832 emit_move_insn (struct_value_rtx,
1834 force_operand (structure_value_addr,
1836 if (GET_CODE (struct_value_rtx) == REG)
1837 use_reg (&call_fusage, struct_value_rtx);
1840 funexp = prepare_call_address (funexp, fndecl, &call_fusage, reg_parm_seen);
1842 /* Now do the register loads required for any wholly-register parms or any
1843 parms which are passed both on the stack and in a register. Their
1844 expressions were already evaluated.
1846 Mark all register-parms as living through the call, putting these USE
1847 insns in the CALL_INSN_FUNCTION_USAGE field. */
1849 for (i = 0; i < num_actuals; i++)
1851 rtx list = args[i].reg;
1852 int partial = args[i].partial;
1859 /* Process each register that needs to get this arg. */
1860 if (GET_CODE (list) == EXPR_LIST)
1861 reg = XEXP (list, 0), list = XEXP (list, 1);
1863 reg = list, list = 0;
1865 /* Set to non-negative if must move a word at a time, even if just
1866 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1867 we just use a normal move insn. This value can be zero if the
1868 argument is a zero size structure with no fields. */
1869 nregs = (partial ? partial
1870 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1871 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1872 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1875 /* If simple case, just do move. If normal partial, store_one_arg
1876 has already loaded the register for us. In all other cases,
1877 load the register(s) from memory. */
1880 emit_move_insn (reg, args[i].value);
1882 #ifdef STRICT_ALIGNMENT
1883 /* If we have pre-computed the values to put in the registers in
1884 the case of non-aligned structures, copy them in now. */
1886 else if (args[i].n_aligned_regs != 0)
1887 for (j = 0; j < args[i].n_aligned_regs; j++)
1888 emit_move_insn (gen_rtx (REG, word_mode, REGNO (reg) + j),
1889 args[i].aligned_regs[j]);
1892 else if (args[i].partial == 0 || args[i].pass_on_stack)
1893 move_block_to_reg (REGNO (reg),
1894 validize_mem (args[i].value), nregs,
1898 use_reg (&call_fusage, reg);
1900 use_regs (&call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1902 /* PARTIAL referred only to the first register, so clear it for the
1908 /* Perform postincrements before actually calling the function. */
1911 /* All arguments and registers used for the call must be set up by now! */
1913 /* Generate the actual call instruction. */
1914 emit_call_1 (funexp, fndecl, funtype, args_size.constant, struct_value_size,
1915 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
1916 valreg, old_inhibit_defer_pop, call_fusage, is_const);
1918 /* If call is cse'able, make appropriate pair of reg-notes around it.
1919 Test valreg so we don't crash; may safely ignore `const'
1920 if return type is void. */
1921 if (is_const && valreg != 0)
1924 rtx temp = gen_reg_rtx (GET_MODE (valreg));
1927 /* Construct an "equal form" for the value which mentions all the
1928 arguments in order as well as the function name. */
1929 #ifdef PUSH_ARGS_REVERSED
1930 for (i = 0; i < num_actuals; i++)
1931 note = gen_rtx (EXPR_LIST, VOIDmode, args[i].initial_value, note);
1933 for (i = num_actuals - 1; i >= 0; i--)
1934 note = gen_rtx (EXPR_LIST, VOIDmode, args[i].initial_value, note);
1936 note = gen_rtx (EXPR_LIST, VOIDmode, funexp, note);
1938 insns = get_insns ();
1941 emit_libcall_block (insns, temp, valreg, note);
1947 /* Otherwise, just write out the sequence without a note. */
1948 rtx insns = get_insns ();
1954 /* For calls to `setjmp', etc., inform flow.c it should complain
1955 if nonvolatile values are live. */
1959 emit_note (name, NOTE_INSN_SETJMP);
1960 current_function_calls_setjmp = 1;
1964 current_function_calls_longjmp = 1;
1966 /* Notice functions that cannot return.
1967 If optimizing, insns emitted below will be dead.
1968 If not optimizing, they will exist, which is useful
1969 if the user uses the `return' command in the debugger. */
1971 if (is_volatile || is_longjmp)
1974 /* If value type not void, return an rtx for the value. */
1976 /* If there are cleanups to be called, don't use a hard reg as target. */
1977 if (cleanups_this_call != old_cleanups
1978 && target && REG_P (target)
1979 && REGNO (target) < FIRST_PSEUDO_REGISTER)
1982 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
1985 target = const0_rtx;
1987 else if (structure_value_addr)
1989 if (target == 0 || GET_CODE (target) != MEM)
1991 target = gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)),
1992 memory_address (TYPE_MODE (TREE_TYPE (exp)),
1993 structure_value_addr));
1994 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
1997 else if (pcc_struct_value)
2001 /* We used leave the value in the location that it is
2002 returned in, but that causes problems if it is used more
2003 than once in one expression. Rather than trying to track
2004 when a copy is required, we always copy when TARGET is
2005 not specified. This calling sequence is only used on
2006 a few machines and TARGET is usually nonzero. */
2007 if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
2009 target = assign_stack_temp (BLKmode,
2010 int_size_in_bytes (TREE_TYPE (exp)),
2013 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
2015 /* Save this temp slot around the pop below. */
2016 preserve_temp_slots (target);
2019 target = gen_reg_rtx (TYPE_MODE (TREE_TYPE (exp)));
2022 if (TYPE_MODE (TREE_TYPE (exp)) != BLKmode)
2023 emit_move_insn (target, gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)),
2024 copy_to_reg (valreg)));
2026 emit_block_move (target, gen_rtx (MEM, BLKmode, copy_to_reg (valreg)),
2028 TYPE_ALIGN (TREE_TYPE (exp)) / BITS_PER_UNIT);
2030 else if (target && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
2031 && GET_MODE (target) == GET_MODE (valreg))
2032 /* TARGET and VALREG cannot be equal at this point because the latter
2033 would not have REG_FUNCTION_VALUE_P true, while the former would if
2034 it were referring to the same register.
2036 If they refer to the same register, this move will be a no-op, except
2037 when function inlining is being done. */
2038 emit_move_insn (target, valreg);
2039 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
2041 /* Some machines (the PA for example) want to return all small
2042 structures in registers regardless of the structure's alignment.
2044 Deal with them explicitly by copying from the return registers
2045 into the target MEM locations. */
2046 int bytes = int_size_in_bytes (TREE_TYPE (exp));
2047 int n_regs = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
2049 enum machine_mode tmpmode;
2051 int bitsize = MIN (TYPE_ALIGN (TREE_TYPE (exp)), BITS_PER_WORD);
2052 int bitpos, xbitpos, big_endian_correction = 0;
2056 target = assign_stack_temp (BLKmode, bytes, 0);
2057 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
2058 preserve_temp_slots (target);
2061 /* This code assumes valreg is at least a full word. If it isn't,
2062 copy it into a new pseudo which is a full word. */
2063 if (GET_MODE (valreg) != BLKmode
2064 && GET_MODE_SIZE (GET_MODE (valreg)) < UNITS_PER_WORD)
2065 valreg = convert_to_mode (SImode, valreg,
2066 TREE_UNSIGNED (TREE_TYPE (exp)));
2068 /* Structures whose size is not a multiple of a word are aligned
2069 to the least significant byte (to the right). On a BYTES_BIG_ENDIAN
2070 machine, this means we must skip the empty high order bytes when
2071 calculating the bit offset. */
2072 if (BYTES_BIG_ENDIAN && bytes % UNITS_PER_WORD)
2073 big_endian_correction = (BITS_PER_WORD - ((bytes % UNITS_PER_WORD)
2076 /* Copy the structure BITSIZE bites at a time.
2078 We could probably emit more efficient code for machines
2079 which do not use strict alignment, but it doesn't seem
2080 worth the effort at the current time. */
2081 for (bitpos = 0, xbitpos = big_endian_correction;
2082 bitpos < bytes * BITS_PER_UNIT;
2083 bitpos += bitsize, xbitpos += bitsize)
2086 /* We need a new source operand each time xbitpos is on a
2087 word boundary and when xbitpos == big_endian_correction
2088 (the first time through). */
2089 if (xbitpos % BITS_PER_WORD == 0
2090 || xbitpos == big_endian_correction)
2091 src = operand_subword_force (valreg,
2092 xbitpos / BITS_PER_WORD,
2095 /* We need a new destination operand each time bitpos is on
2097 if (bitpos % BITS_PER_WORD == 0)
2098 dst = operand_subword (target, bitpos / BITS_PER_WORD, 1, BLKmode);
2100 /* Use xbitpos for the source extraction (right justified) and
2101 xbitpos for the destination store (left justified). */
2102 store_bit_field (dst, bitsize, bitpos % BITS_PER_WORD, word_mode,
2103 extract_bit_field (src, bitsize,
2104 xbitpos % BITS_PER_WORD, 1,
2105 NULL_RTX, word_mode,
2107 bitsize / BITS_PER_UNIT,
2109 bitsize / BITS_PER_UNIT, BITS_PER_WORD);
2113 target = copy_to_reg (valreg);
2115 #ifdef PROMOTE_FUNCTION_RETURN
2116 /* If we promoted this return value, make the proper SUBREG. TARGET
2117 might be const0_rtx here, so be careful. */
2118 if (GET_CODE (target) == REG
2119 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
2120 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
2122 tree type = TREE_TYPE (exp);
2123 int unsignedp = TREE_UNSIGNED (type);
2125 /* If we don't promote as expected, something is wrong. */
2126 if (GET_MODE (target)
2127 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
2130 target = gen_rtx (SUBREG, TYPE_MODE (type), target, 0);
2131 SUBREG_PROMOTED_VAR_P (target) = 1;
2132 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
2136 if (flag_short_temps)
2138 /* Perform all cleanups needed for the arguments of this call
2139 (i.e. destructors in C++). */
2140 expand_cleanups_to (old_cleanups);
2143 /* If size of args is variable or this was a constructor call for a stack
2144 argument, restore saved stack-pointer value. */
2146 if (old_stack_level)
2148 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
2149 pending_stack_adjust = old_pending_adj;
2150 #ifdef ACCUMULATE_OUTGOING_ARGS
2151 stack_arg_under_construction = old_stack_arg_under_construction;
2152 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2153 stack_usage_map = initial_stack_usage_map;
2156 #ifdef ACCUMULATE_OUTGOING_ARGS
2159 #ifdef REG_PARM_STACK_SPACE
2162 enum machine_mode save_mode = GET_MODE (save_area);
2164 = gen_rtx (MEM, save_mode,
2165 memory_address (save_mode,
2166 #ifdef ARGS_GROW_DOWNWARD
2167 plus_constant (argblock, - high_to_save)
2169 plus_constant (argblock, low_to_save)
2173 if (save_mode != BLKmode)
2174 emit_move_insn (stack_area, save_area);
2176 emit_block_move (stack_area, validize_mem (save_area),
2177 GEN_INT (high_to_save - low_to_save + 1),
2178 PARM_BOUNDARY / BITS_PER_UNIT);
2182 /* If we saved any argument areas, restore them. */
2183 for (i = 0; i < num_actuals; i++)
2184 if (args[i].save_area)
2186 enum machine_mode save_mode = GET_MODE (args[i].save_area);
2188 = gen_rtx (MEM, save_mode,
2189 memory_address (save_mode,
2190 XEXP (args[i].stack_slot, 0)));
2192 if (save_mode != BLKmode)
2193 emit_move_insn (stack_area, args[i].save_area);
2195 emit_block_move (stack_area, validize_mem (args[i].save_area),
2196 GEN_INT (args[i].size.constant),
2197 PARM_BOUNDARY / BITS_PER_UNIT);
2200 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2201 stack_usage_map = initial_stack_usage_map;
2205 /* If this was alloca, record the new stack level for nonlocal gotos.
2206 Check for the handler slots since we might not have a save area
2207 for non-local gotos. */
2209 if (may_be_alloca && nonlocal_goto_handler_slot != 0)
2210 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
2217 /* Output a library call to function FUN (a SYMBOL_REF rtx)
2218 (emitting the queue unless NO_QUEUE is nonzero),
2219 for a value of mode OUTMODE,
2220 with NARGS different arguments, passed as alternating rtx values
2221 and machine_modes to convert them to.
2222 The rtx values should have been passed through protect_from_queue already.
2224 NO_QUEUE will be true if and only if the library call is a `const' call
2225 which will be enclosed in REG_LIBCALL/REG_RETVAL notes; it is equivalent
2226 to the variable is_const in expand_call.
2228 NO_QUEUE must be true for const calls, because if it isn't, then
2229 any pending increment will be emitted between REG_LIBCALL/REG_RETVAL notes,
2230 and will be lost if the libcall sequence is optimized away.
2232 NO_QUEUE must be false for non-const calls, because if it isn't, the
2233 call insn will have its CONST_CALL_P bit set, and it will be incorrectly
2234 optimized. For instance, the instruction scheduler may incorrectly
2235 move memory references across the non-const call. */
2238 emit_library_call VPROTO((rtx orgfun, int no_queue, enum machine_mode outmode,
2244 enum machine_mode outmode;
2248 /* Total size in bytes of all the stack-parms scanned so far. */
2249 struct args_size args_size;
2250 /* Size of arguments before any adjustments (such as rounding). */
2251 struct args_size original_args_size;
2252 register int argnum;
2257 CUMULATIVE_ARGS args_so_far;
2258 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2259 struct args_size offset; struct args_size size; };
2261 int old_inhibit_defer_pop = inhibit_defer_pop;
2262 rtx call_fusage = 0;
2263 /* library calls are never indirect calls. */
2264 int current_call_is_indirect = 0;
2266 VA_START (p, nargs);
2269 orgfun = va_arg (p, rtx);
2270 no_queue = va_arg (p, int);
2271 outmode = va_arg (p, enum machine_mode);
2272 nargs = va_arg (p, int);
2277 /* Copy all the libcall-arguments out of the varargs data
2278 and into a vector ARGVEC.
2280 Compute how to pass each argument. We only support a very small subset
2281 of the full argument passing conventions to limit complexity here since
2282 library functions shouldn't have many args. */
2284 argvec = (struct arg *) alloca (nargs * sizeof (struct arg));
2286 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun);
2288 args_size.constant = 0;
2293 for (count = 0; count < nargs; count++)
2295 rtx val = va_arg (p, rtx);
2296 enum machine_mode mode = va_arg (p, enum machine_mode);
2298 /* We cannot convert the arg value to the mode the library wants here;
2299 must do it earlier where we know the signedness of the arg. */
2301 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2304 /* On some machines, there's no way to pass a float to a library fcn.
2305 Pass it as a double instead. */
2306 #ifdef LIBGCC_NEEDS_DOUBLE
2307 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2308 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
2311 /* There's no need to call protect_from_queue, because
2312 either emit_move_insn or emit_push_insn will do that. */
2314 /* Make sure it is a reasonable operand for a move or push insn. */
2315 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2316 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2317 val = force_operand (val, NULL_RTX);
2319 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2320 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2322 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2323 be viewed as just an efficiency improvement. */
2324 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2325 emit_move_insn (slot, val);
2326 val = force_operand (XEXP (slot, 0), NULL_RTX);
2331 argvec[count].value = val;
2332 argvec[count].mode = mode;
2334 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2335 if (argvec[count].reg && GET_CODE (argvec[count].reg) == EXPR_LIST)
2337 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2338 argvec[count].partial
2339 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2341 argvec[count].partial = 0;
2344 locate_and_pad_parm (mode, NULL_TREE,
2345 argvec[count].reg && argvec[count].partial == 0,
2346 NULL_TREE, &args_size, &argvec[count].offset,
2347 &argvec[count].size);
2349 if (argvec[count].size.var)
2352 #ifndef REG_PARM_STACK_SPACE
2353 if (argvec[count].partial)
2354 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2357 if (argvec[count].reg == 0 || argvec[count].partial != 0
2358 #ifdef REG_PARM_STACK_SPACE
2362 args_size.constant += argvec[count].size.constant;
2364 #ifdef ACCUMULATE_OUTGOING_ARGS
2365 /* If this arg is actually passed on the stack, it might be
2366 clobbering something we already put there (this library call might
2367 be inside the evaluation of an argument to a function whose call
2368 requires the stack). This will only occur when the library call
2369 has sufficient args to run out of argument registers. Abort in
2370 this case; if this ever occurs, code must be added to save and
2371 restore the arg slot. */
2373 if (argvec[count].reg == 0 || argvec[count].partial != 0)
2377 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree)0, 1);
2381 /* If this machine requires an external definition for library
2382 functions, write one out. */
2383 assemble_external_libcall (fun);
2385 original_args_size = args_size;
2386 #ifdef STACK_BOUNDARY
2387 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2388 / STACK_BYTES) * STACK_BYTES);
2391 #ifdef REG_PARM_STACK_SPACE
2392 args_size.constant = MAX (args_size.constant,
2393 REG_PARM_STACK_SPACE (NULL_TREE));
2394 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2395 args_size.constant -= REG_PARM_STACK_SPACE (NULL_TREE);
2399 if (args_size.constant > current_function_outgoing_args_size)
2400 current_function_outgoing_args_size = args_size.constant;
2402 #ifdef ACCUMULATE_OUTGOING_ARGS
2403 args_size.constant = 0;
2406 #ifndef PUSH_ROUNDING
2407 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2410 #ifdef PUSH_ARGS_REVERSED
2411 #ifdef STACK_BOUNDARY
2412 /* If we push args individually in reverse order, perform stack alignment
2413 before the first push (the last arg). */
2415 anti_adjust_stack (GEN_INT (args_size.constant
2416 - original_args_size.constant));
2420 #ifdef PUSH_ARGS_REVERSED
2428 /* Push the args that need to be pushed. */
2430 for (count = 0; count < nargs; count++, argnum += inc)
2432 register enum machine_mode mode = argvec[argnum].mode;
2433 register rtx val = argvec[argnum].value;
2434 rtx reg = argvec[argnum].reg;
2435 int partial = argvec[argnum].partial;
2437 if (! (reg != 0 && partial == 0))
2438 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2439 argblock, GEN_INT (argvec[count].offset.constant));
2443 #ifndef PUSH_ARGS_REVERSED
2444 #ifdef STACK_BOUNDARY
2445 /* If we pushed args in forward order, perform stack alignment
2446 after pushing the last arg. */
2448 anti_adjust_stack (GEN_INT (args_size.constant
2449 - original_args_size.constant));
2453 #ifdef PUSH_ARGS_REVERSED
2459 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
2461 /* Now load any reg parms into their regs. */
2463 for (count = 0; count < nargs; count++, argnum += inc)
2465 register enum machine_mode mode = argvec[argnum].mode;
2466 register rtx val = argvec[argnum].value;
2467 rtx reg = argvec[argnum].reg;
2468 int partial = argvec[argnum].partial;
2470 if (reg != 0 && partial == 0)
2471 emit_move_insn (reg, val);
2475 /* For version 1.37, try deleting this entirely. */
2479 /* Any regs containing parms remain in use through the call. */
2480 for (count = 0; count < nargs; count++)
2481 if (argvec[count].reg != 0)
2482 use_reg (&call_fusage, argvec[count].reg);
2484 /* Don't allow popping to be deferred, since then
2485 cse'ing of library calls could delete a call and leave the pop. */
2488 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2489 will set inhibit_defer_pop to that value. */
2492 get_identifier (XSTR (orgfun, 0)),
2493 get_identifier (XSTR (orgfun, 0)), args_size.constant, 0,
2494 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2495 outmode != VOIDmode ? hard_libcall_value (outmode) : NULL_RTX,
2496 old_inhibit_defer_pop + 1, call_fusage, no_queue);
2500 /* Now restore inhibit_defer_pop to its actual original value. */
2504 /* Like emit_library_call except that an extra argument, VALUE,
2505 comes second and says where to store the result.
2506 (If VALUE is zero, this function chooses a convenient way
2507 to return the value.
2509 This function returns an rtx for where the value is to be found.
2510 If VALUE is nonzero, VALUE is returned. */
2513 emit_library_call_value VPROTO((rtx orgfun, rtx value, int no_queue,
2514 enum machine_mode outmode, int nargs, ...))
2520 enum machine_mode outmode;
2524 /* Total size in bytes of all the stack-parms scanned so far. */
2525 struct args_size args_size;
2526 /* Size of arguments before any adjustments (such as rounding). */
2527 struct args_size original_args_size;
2528 register int argnum;
2533 CUMULATIVE_ARGS args_so_far;
2534 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2535 struct args_size offset; struct args_size size; };
2537 int old_inhibit_defer_pop = inhibit_defer_pop;
2538 rtx call_fusage = 0;
2540 int pcc_struct_value = 0;
2541 int struct_value_size = 0;
2542 /* library calls are never indirect calls. */
2543 int current_call_is_indirect = 0;
2546 VA_START (p, nargs);
2549 orgfun = va_arg (p, rtx);
2550 value = va_arg (p, rtx);
2551 no_queue = va_arg (p, int);
2552 outmode = va_arg (p, enum machine_mode);
2553 nargs = va_arg (p, int);
2556 is_const = no_queue;
2559 /* If this kind of value comes back in memory,
2560 decide where in memory it should come back. */
2561 if (aggregate_value_p (type_for_mode (outmode, 0)))
2563 #ifdef PCC_STATIC_STRUCT_RETURN
2565 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
2567 mem_value = gen_rtx (MEM, outmode, pointer_reg);
2568 pcc_struct_value = 1;
2570 value = gen_reg_rtx (outmode);
2571 #else /* not PCC_STATIC_STRUCT_RETURN */
2572 struct_value_size = GET_MODE_SIZE (outmode);
2573 if (value != 0 && GET_CODE (value) == MEM)
2576 mem_value = assign_stack_temp (outmode, GET_MODE_SIZE (outmode), 0);
2579 /* This call returns a big structure. */
2583 /* ??? Unfinished: must pass the memory address as an argument. */
2585 /* Copy all the libcall-arguments out of the varargs data
2586 and into a vector ARGVEC.
2588 Compute how to pass each argument. We only support a very small subset
2589 of the full argument passing conventions to limit complexity here since
2590 library functions shouldn't have many args. */
2592 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
2594 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun);
2596 args_size.constant = 0;
2603 /* If there's a structure value address to be passed,
2604 either pass it in the special place, or pass it as an extra argument. */
2605 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
2607 rtx addr = XEXP (mem_value, 0);
2610 /* Make sure it is a reasonable operand for a move or push insn. */
2611 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
2612 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
2613 addr = force_operand (addr, NULL_RTX);
2615 argvec[count].value = addr;
2616 argvec[count].mode = Pmode;
2617 argvec[count].partial = 0;
2619 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
2620 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2621 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
2625 locate_and_pad_parm (Pmode, NULL_TREE,
2626 argvec[count].reg && argvec[count].partial == 0,
2627 NULL_TREE, &args_size, &argvec[count].offset,
2628 &argvec[count].size);
2631 if (argvec[count].reg == 0 || argvec[count].partial != 0
2632 #ifdef REG_PARM_STACK_SPACE
2636 args_size.constant += argvec[count].size.constant;
2638 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree)0, 1);
2643 for (; count < nargs; count++)
2645 rtx val = va_arg (p, rtx);
2646 enum machine_mode mode = va_arg (p, enum machine_mode);
2648 /* We cannot convert the arg value to the mode the library wants here;
2649 must do it earlier where we know the signedness of the arg. */
2651 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2654 /* On some machines, there's no way to pass a float to a library fcn.
2655 Pass it as a double instead. */
2656 #ifdef LIBGCC_NEEDS_DOUBLE
2657 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2658 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
2661 /* There's no need to call protect_from_queue, because
2662 either emit_move_insn or emit_push_insn will do that. */
2664 /* Make sure it is a reasonable operand for a move or push insn. */
2665 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2666 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2667 val = force_operand (val, NULL_RTX);
2669 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2670 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2672 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2673 be viewed as just an efficiency improvement. */
2674 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2675 emit_move_insn (slot, val);
2676 val = XEXP (slot, 0);
2681 argvec[count].value = val;
2682 argvec[count].mode = mode;
2684 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2685 if (argvec[count].reg && GET_CODE (argvec[count].reg) == EXPR_LIST)
2687 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2688 argvec[count].partial
2689 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2691 argvec[count].partial = 0;
2694 locate_and_pad_parm (mode, NULL_TREE,
2695 argvec[count].reg && argvec[count].partial == 0,
2696 NULL_TREE, &args_size, &argvec[count].offset,
2697 &argvec[count].size);
2699 if (argvec[count].size.var)
2702 #ifndef REG_PARM_STACK_SPACE
2703 if (argvec[count].partial)
2704 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2707 if (argvec[count].reg == 0 || argvec[count].partial != 0
2708 #ifdef REG_PARM_STACK_SPACE
2712 args_size.constant += argvec[count].size.constant;
2714 #ifdef ACCUMULATE_OUTGOING_ARGS
2715 /* If this arg is actually passed on the stack, it might be
2716 clobbering something we already put there (this library call might
2717 be inside the evaluation of an argument to a function whose call
2718 requires the stack). This will only occur when the library call
2719 has sufficient args to run out of argument registers. Abort in
2720 this case; if this ever occurs, code must be added to save and
2721 restore the arg slot. */
2723 if (argvec[count].reg == 0 || argvec[count].partial != 0)
2727 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree)0, 1);
2731 /* If this machine requires an external definition for library
2732 functions, write one out. */
2733 assemble_external_libcall (fun);
2735 original_args_size = args_size;
2736 #ifdef STACK_BOUNDARY
2737 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2738 / STACK_BYTES) * STACK_BYTES);
2741 #ifdef REG_PARM_STACK_SPACE
2742 args_size.constant = MAX (args_size.constant,
2743 REG_PARM_STACK_SPACE (NULL_TREE));
2744 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2745 args_size.constant -= REG_PARM_STACK_SPACE (NULL_TREE);
2749 if (args_size.constant > current_function_outgoing_args_size)
2750 current_function_outgoing_args_size = args_size.constant;
2752 #ifdef ACCUMULATE_OUTGOING_ARGS
2753 args_size.constant = 0;
2756 #ifndef PUSH_ROUNDING
2757 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2760 #ifdef PUSH_ARGS_REVERSED
2761 #ifdef STACK_BOUNDARY
2762 /* If we push args individually in reverse order, perform stack alignment
2763 before the first push (the last arg). */
2765 anti_adjust_stack (GEN_INT (args_size.constant
2766 - original_args_size.constant));
2770 #ifdef PUSH_ARGS_REVERSED
2778 /* Push the args that need to be pushed. */
2780 for (count = 0; count < nargs; count++, argnum += inc)
2782 register enum machine_mode mode = argvec[argnum].mode;
2783 register rtx val = argvec[argnum].value;
2784 rtx reg = argvec[argnum].reg;
2785 int partial = argvec[argnum].partial;
2787 if (! (reg != 0 && partial == 0))
2788 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2789 argblock, GEN_INT (argvec[count].offset.constant));
2793 #ifndef PUSH_ARGS_REVERSED
2794 #ifdef STACK_BOUNDARY
2795 /* If we pushed args in forward order, perform stack alignment
2796 after pushing the last arg. */
2798 anti_adjust_stack (GEN_INT (args_size.constant
2799 - original_args_size.constant));
2803 #ifdef PUSH_ARGS_REVERSED
2809 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
2811 /* Now load any reg parms into their regs. */
2813 for (count = 0; count < nargs; count++, argnum += inc)
2815 register enum machine_mode mode = argvec[argnum].mode;
2816 register rtx val = argvec[argnum].value;
2817 rtx reg = argvec[argnum].reg;
2818 int partial = argvec[argnum].partial;
2820 if (reg != 0 && partial == 0)
2821 emit_move_insn (reg, val);
2826 /* For version 1.37, try deleting this entirely. */
2831 /* Any regs containing parms remain in use through the call. */
2832 for (count = 0; count < nargs; count++)
2833 if (argvec[count].reg != 0)
2834 use_reg (&call_fusage, argvec[count].reg);
2836 /* Pass the function the address in which to return a structure value. */
2837 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
2839 emit_move_insn (struct_value_rtx,
2841 force_operand (XEXP (mem_value, 0),
2843 if (GET_CODE (struct_value_rtx) == REG)
2844 use_reg (&call_fusage, struct_value_rtx);
2847 /* Don't allow popping to be deferred, since then
2848 cse'ing of library calls could delete a call and leave the pop. */
2851 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2852 will set inhibit_defer_pop to that value. */
2855 get_identifier (XSTR (orgfun, 0)),
2856 get_identifier (XSTR (orgfun, 0)), args_size.constant,
2858 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2859 (outmode != VOIDmode && mem_value == 0
2860 ? hard_libcall_value (outmode) : NULL_RTX),
2861 old_inhibit_defer_pop + 1, call_fusage, is_const);
2863 /* Now restore inhibit_defer_pop to its actual original value. */
2868 /* Copy the value to the right place. */
2869 if (outmode != VOIDmode)
2875 if (value != mem_value)
2876 emit_move_insn (value, mem_value);
2878 else if (value != 0)
2879 emit_move_insn (value, hard_libcall_value (outmode));
2881 value = hard_libcall_value (outmode);
2888 /* Return an rtx which represents a suitable home on the stack
2889 given TYPE, the type of the argument looking for a home.
2890 This is called only for BLKmode arguments.
2892 SIZE is the size needed for this target.
2893 ARGS_ADDR is the address of the bottom of the argument block for this call.
2894 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
2895 if this machine uses push insns. */
2898 target_for_arg (type, size, args_addr, offset)
2902 struct args_size offset;
2905 rtx offset_rtx = ARGS_SIZE_RTX (offset);
2907 /* We do not call memory_address if possible,
2908 because we want to address as close to the stack
2909 as possible. For non-variable sized arguments,
2910 this will be stack-pointer relative addressing. */
2911 if (GET_CODE (offset_rtx) == CONST_INT)
2912 target = plus_constant (args_addr, INTVAL (offset_rtx));
2915 /* I have no idea how to guarantee that this
2916 will work in the presence of register parameters. */
2917 target = gen_rtx (PLUS, Pmode, args_addr, offset_rtx);
2918 target = memory_address (QImode, target);
2921 return gen_rtx (MEM, BLKmode, target);
2925 /* Store a single argument for a function call
2926 into the register or memory area where it must be passed.
2927 *ARG describes the argument value and where to pass it.
2929 ARGBLOCK is the address of the stack-block for all the arguments,
2930 or 0 on a machine where arguments are pushed individually.
2932 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
2933 so must be careful about how the stack is used.
2935 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
2936 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
2937 that we need not worry about saving and restoring the stack.
2939 FNDECL is the declaration of the function we are calling. */
2942 store_one_arg (arg, argblock, may_be_alloca, variable_size, fndecl,
2943 reg_parm_stack_space)
2944 struct arg_data *arg;
2949 int reg_parm_stack_space;
2951 register tree pval = arg->tree_value;
2955 int i, lower_bound, upper_bound;
2957 if (TREE_CODE (pval) == ERROR_MARK)
2960 /* Push a new temporary level for any temporaries we make for
2964 #ifdef ACCUMULATE_OUTGOING_ARGS
2965 /* If this is being stored into a pre-allocated, fixed-size, stack area,
2966 save any previous data at that location. */
2967 if (argblock && ! variable_size && arg->stack)
2969 #ifdef ARGS_GROW_DOWNWARD
2970 /* stack_slot is negative, but we want to index stack_usage_map */
2971 /* with positive values. */
2972 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
2973 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
2977 lower_bound = upper_bound - arg->size.constant;
2979 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
2980 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
2984 upper_bound = lower_bound + arg->size.constant;
2987 for (i = lower_bound; i < upper_bound; i++)
2988 if (stack_usage_map[i]
2989 #ifdef REG_PARM_STACK_SPACE
2990 /* Don't store things in the fixed argument area at this point;
2991 it has already been saved. */
2992 && i > reg_parm_stack_space
2997 if (i != upper_bound)
2999 /* We need to make a save area. See what mode we can make it. */
3000 enum machine_mode save_mode
3001 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
3003 = gen_rtx (MEM, save_mode,
3004 memory_address (save_mode, XEXP (arg->stack_slot, 0)));
3006 if (save_mode == BLKmode)
3008 arg->save_area = assign_stack_temp (BLKmode,
3009 arg->size.constant, 0);
3010 MEM_IN_STRUCT_P (arg->save_area)
3011 = AGGREGATE_TYPE_P (TREE_TYPE (arg->tree_value));
3012 preserve_temp_slots (arg->save_area);
3013 emit_block_move (validize_mem (arg->save_area), stack_area,
3014 GEN_INT (arg->size.constant),
3015 PARM_BOUNDARY / BITS_PER_UNIT);
3019 arg->save_area = gen_reg_rtx (save_mode);
3020 emit_move_insn (arg->save_area, stack_area);
3026 /* If this isn't going to be placed on both the stack and in registers,
3027 set up the register and number of words. */
3028 if (! arg->pass_on_stack)
3029 reg = arg->reg, partial = arg->partial;
3031 if (reg != 0 && partial == 0)
3032 /* Being passed entirely in a register. We shouldn't be called in
3036 #ifdef STRICT_ALIGNMENT
3037 /* If this arg needs special alignment, don't load the registers
3039 if (arg->n_aligned_regs != 0)
3043 /* If this is being partially passed in a register, but multiple locations
3044 are specified, we assume that the one partially used is the one that is
3046 if (reg && GET_CODE (reg) == EXPR_LIST)
3047 reg = XEXP (reg, 0);
3049 /* If this is being passed partially in a register, we can't evaluate
3050 it directly into its stack slot. Otherwise, we can. */
3051 if (arg->value == 0)
3053 #ifdef ACCUMULATE_OUTGOING_ARGS
3054 /* stack_arg_under_construction is nonzero if a function argument is
3055 being evaluated directly into the outgoing argument list and
3056 expand_call must take special action to preserve the argument list
3057 if it is called recursively.
3059 For scalar function arguments stack_usage_map is sufficient to
3060 determine which stack slots must be saved and restored. Scalar
3061 arguments in general have pass_on_stack == 0.
3063 If this argument is initialized by a function which takes the
3064 address of the argument (a C++ constructor or a C function
3065 returning a BLKmode structure), then stack_usage_map is
3066 insufficient and expand_call must push the stack around the
3067 function call. Such arguments have pass_on_stack == 1.
3069 Note that it is always safe to set stack_arg_under_construction,
3070 but this generates suboptimal code if set when not needed. */
3072 if (arg->pass_on_stack)
3073 stack_arg_under_construction++;
3075 arg->value = expand_expr (pval,
3077 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
3078 ? NULL_RTX : arg->stack,
3081 /* If we are promoting object (or for any other reason) the mode
3082 doesn't agree, convert the mode. */
3084 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
3085 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
3086 arg->value, arg->unsignedp);
3088 #ifdef ACCUMULATE_OUTGOING_ARGS
3089 if (arg->pass_on_stack)
3090 stack_arg_under_construction--;
3094 /* Don't allow anything left on stack from computation
3095 of argument to alloca. */
3097 do_pending_stack_adjust ();
3099 if (arg->value == arg->stack)
3100 /* If the value is already in the stack slot, we are done. */
3102 else if (arg->mode != BLKmode)
3106 /* Argument is a scalar, not entirely passed in registers.
3107 (If part is passed in registers, arg->partial says how much
3108 and emit_push_insn will take care of putting it there.)
3110 Push it, and if its size is less than the
3111 amount of space allocated to it,
3112 also bump stack pointer by the additional space.
3113 Note that in C the default argument promotions
3114 will prevent such mismatches. */
3116 size = GET_MODE_SIZE (arg->mode);
3117 /* Compute how much space the push instruction will push.
3118 On many machines, pushing a byte will advance the stack
3119 pointer by a halfword. */
3120 #ifdef PUSH_ROUNDING
3121 size = PUSH_ROUNDING (size);
3125 /* Compute how much space the argument should get:
3126 round up to a multiple of the alignment for arguments. */
3127 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
3128 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
3129 / (PARM_BOUNDARY / BITS_PER_UNIT))
3130 * (PARM_BOUNDARY / BITS_PER_UNIT));
3132 /* This isn't already where we want it on the stack, so put it there.
3133 This can either be done with push or copy insns. */
3134 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
3135 0, partial, reg, used - size,
3136 argblock, ARGS_SIZE_RTX (arg->offset));
3140 /* BLKmode, at least partly to be pushed. */
3142 register int excess;
3145 /* Pushing a nonscalar.
3146 If part is passed in registers, PARTIAL says how much
3147 and emit_push_insn will take care of putting it there. */
3149 /* Round its size up to a multiple
3150 of the allocation unit for arguments. */
3152 if (arg->size.var != 0)
3155 size_rtx = ARGS_SIZE_RTX (arg->size);
3159 /* PUSH_ROUNDING has no effect on us, because
3160 emit_push_insn for BLKmode is careful to avoid it. */
3161 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
3162 + partial * UNITS_PER_WORD);
3163 size_rtx = expr_size (pval);
3166 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
3167 TYPE_ALIGN (TREE_TYPE (pval)) / BITS_PER_UNIT, partial,
3168 reg, excess, argblock, ARGS_SIZE_RTX (arg->offset));
3172 /* Unless this is a partially-in-register argument, the argument is now
3175 ??? Note that this can change arg->value from arg->stack to
3176 arg->stack_slot and it matters when they are not the same.
3177 It isn't totally clear that this is correct in all cases. */
3179 arg->value = arg->stack_slot;
3181 /* Once we have pushed something, pops can't safely
3182 be deferred during the rest of the arguments. */
3185 /* ANSI doesn't require a sequence point here,
3186 but PCC has one, so this will avoid some problems. */
3189 /* Free any temporary slots made in processing this argument. Show
3190 that we might have taken the address of something and pushed that
3192 preserve_temp_slots (NULL_RTX);
3196 #ifdef ACCUMULATE_OUTGOING_ARGS
3197 /* Now mark the segment we just used. */
3198 if (argblock && ! variable_size && arg->stack)
3199 for (i = lower_bound; i < upper_bound; i++)
3200 stack_usage_map[i] = 1;