1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
30 #include "insn-flags.h"
32 /* Decide whether a function's arguments should be processed
33 from first to last or from last to first.
35 They should if the stack and args grow in opposite directions, but
36 only if we have push insns. */
40 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
41 #define PUSH_ARGS_REVERSED /* If it's last to first */
46 /* Like STACK_BOUNDARY but in units of bytes, not bits. */
47 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
49 /* Data structure and subroutines used within expand_call. */
53 /* Tree node for this argument. */
55 /* Mode for value; TYPE_MODE unless promoted. */
56 enum machine_mode mode;
57 /* Current RTL value for argument, or 0 if it isn't precomputed. */
59 /* Initially-compute RTL value for argument; only for const functions. */
61 /* Register to pass this argument in, 0 if passed on stack, or an
62 EXPR_LIST if the arg is to be copied into multiple different
65 /* If REG was promoted from the actual mode of the argument expression,
66 indicates whether the promotion is sign- or zero-extended. */
68 /* Number of registers to use. 0 means put the whole arg in registers.
69 Also 0 if not passed in registers. */
71 /* Non-zero if argument must be passed on stack.
72 Note that some arguments may be passed on the stack
73 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
74 pass_on_stack identifies arguments that *cannot* go in registers. */
76 /* Offset of this argument from beginning of stack-args. */
77 struct args_size offset;
78 /* Similar, but offset to the start of the stack slot. Different from
79 OFFSET if this arg pads downward. */
80 struct args_size slot_offset;
81 /* Size of this argument on the stack, rounded up for any padding it gets,
82 parts of the argument passed in registers do not count.
83 If REG_PARM_STACK_SPACE is defined, then register parms
84 are counted here as well. */
85 struct args_size size;
86 /* Location on the stack at which parameter should be stored. The store
87 has already been done if STACK == VALUE. */
89 /* Location on the stack of the start of this argument slot. This can
90 differ from STACK if this arg pads downward. This location is known
91 to be aligned to FUNCTION_ARG_BOUNDARY. */
93 #ifdef ACCUMULATE_OUTGOING_ARGS
94 /* Place that this stack area has been saved, if needed. */
97 #ifdef STRICT_ALIGNMENT
98 /* If an argument's alignment does not permit direct copying into registers,
99 copy in smaller-sized pieces into pseudos. These are stored in a
100 block pointed to by this field. The next field says how many
101 word-sized pseudos we made. */
107 #ifdef ACCUMULATE_OUTGOING_ARGS
108 /* A vector of one char per byte of stack space. A byte if non-zero if
109 the corresponding stack location has been used.
110 This vector is used to prevent a function call within an argument from
111 clobbering any stack already set up. */
112 static char *stack_usage_map;
114 /* Size of STACK_USAGE_MAP. */
115 static int highest_outgoing_arg_in_use;
117 /* stack_arg_under_construction is nonzero when an argument may be
118 initialized with a constructor call (including a C function that
119 returns a BLKmode struct) and expand_call must take special action
120 to make sure the object being constructed does not overlap the
121 argument list for the constructor call. */
122 int stack_arg_under_construction;
125 static int calls_function PROTO((tree, int));
126 static int calls_function_1 PROTO((tree, int));
127 static void emit_call_1 PROTO((rtx, tree, tree, int, int, rtx, rtx,
129 static void store_one_arg PROTO ((struct arg_data *, rtx, int, int,
132 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
135 If WHICH is 0, return 1 if EXP contains a call to any function.
136 Actually, we only need return 1 if evaluating EXP would require pushing
137 arguments on the stack, but that is too difficult to compute, so we just
138 assume any function call might require the stack. */
140 static tree calls_function_save_exprs;
143 calls_function (exp, which)
148 calls_function_save_exprs = 0;
149 val = calls_function_1 (exp, which);
150 calls_function_save_exprs = 0;
155 calls_function_1 (exp, which)
160 enum tree_code code = TREE_CODE (exp);
161 int type = TREE_CODE_CLASS (code);
162 int length = tree_code_length[(int) code];
164 /* If this code is langauge-specific, we don't know what it will do. */
165 if ((int) code >= NUM_TREE_CODES)
168 /* Only expressions and references can contain calls. */
169 if (type != 'e' && type != '<' && type != '1' && type != '2' && type != 'r'
178 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
179 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
182 tree fndecl = TREE_OPERAND (TREE_OPERAND (exp, 0), 0);
184 if ((DECL_BUILT_IN (fndecl)
185 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_ALLOCA)
186 || (DECL_SAVED_INSNS (fndecl)
187 && (FUNCTION_FLAGS (DECL_SAVED_INSNS (fndecl))
188 & FUNCTION_FLAGS_CALLS_ALLOCA)))
192 /* Third operand is RTL. */
197 if (SAVE_EXPR_RTL (exp) != 0)
199 if (value_member (exp, calls_function_save_exprs))
201 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
202 calls_function_save_exprs);
203 return (TREE_OPERAND (exp, 0) != 0
204 && calls_function_1 (TREE_OPERAND (exp, 0), which));
210 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
211 if (DECL_INITIAL (local) != 0
212 && calls_function_1 (DECL_INITIAL (local), which))
216 register tree subblock;
218 for (subblock = BLOCK_SUBBLOCKS (exp);
220 subblock = TREE_CHAIN (subblock))
221 if (calls_function_1 (subblock, which))
226 case METHOD_CALL_EXPR:
230 case WITH_CLEANUP_EXPR:
238 for (i = 0; i < length; i++)
239 if (TREE_OPERAND (exp, i) != 0
240 && calls_function_1 (TREE_OPERAND (exp, i), which))
246 /* Force FUNEXP into a form suitable for the address of a CALL,
247 and return that as an rtx. Also load the static chain register
248 if FNDECL is a nested function.
250 CALL_FUSAGE points to a variable holding the prospective
251 CALL_INSN_FUNCTION_USAGE information. */
254 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen)
260 rtx static_chain_value = 0;
262 funexp = protect_from_queue (funexp, 0);
265 /* Get possible static chain value for nested function in C. */
266 static_chain_value = lookup_static_chain (fndecl);
268 /* Make a valid memory address and copy constants thru pseudo-regs,
269 but not for a constant address if -fno-function-cse. */
270 if (GET_CODE (funexp) != SYMBOL_REF)
272 #ifdef SMALL_REGISTER_CLASSES
273 /* If we are using registers for parameters, force the
274 function address into a register now. */
275 reg_parm_seen ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
278 memory_address (FUNCTION_MODE, funexp);
281 #ifndef NO_FUNCTION_CSE
282 if (optimize && ! flag_no_function_cse)
283 #ifdef NO_RECURSIVE_FUNCTION_CSE
284 if (fndecl != current_function_decl)
286 funexp = force_reg (Pmode, funexp);
290 if (static_chain_value != 0)
292 emit_move_insn (static_chain_rtx, static_chain_value);
294 use_reg (call_fusage, static_chain_rtx);
300 /* Generate instructions to call function FUNEXP,
301 and optionally pop the results.
302 The CALL_INSN is the first insn generated.
304 FNDECL is the declaration node of the function. This is given ot the
305 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
307 FUNTYPE is the data type of the function, or, for a library call,
308 the identifier for the name of the call. This is given to the
309 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
311 STACK_SIZE is the number of bytes of arguments on the stack,
312 rounded up to STACK_BOUNDARY; zero if the size is variable.
313 This is both to put into the call insn and
314 to generate explicit popping code if necessary.
316 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
317 It is zero if this call doesn't want a structure value.
319 NEXT_ARG_REG is the rtx that results from executing
320 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
321 just after all the args have had their registers assigned.
322 This could be whatever you like, but normally it is the first
323 arg-register beyond those used for args in this call,
324 or 0 if all the arg-registers are used in this call.
325 It is passed on to `gen_call' so you can put this info in the call insn.
327 VALREG is a hard register in which a value is returned,
328 or 0 if the call does not return a value.
330 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
331 the args to this call were processed.
332 We restore `inhibit_defer_pop' to that value.
334 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
335 denote registers used by the called function.
337 IS_CONST is true if this is a `const' call. */
340 emit_call_1 (funexp, fndecl, funtype, stack_size, struct_value_size,
341 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
347 int struct_value_size;
350 int old_inhibit_defer_pop;
354 rtx stack_size_rtx = GEN_INT (stack_size);
355 rtx struct_value_size_rtx = GEN_INT (struct_value_size);
357 int already_popped = 0;
359 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
360 and we don't want to load it into a register as an optimization,
361 because prepare_call_address already did it if it should be done. */
362 if (GET_CODE (funexp) != SYMBOL_REF)
363 funexp = memory_address (FUNCTION_MODE, funexp);
365 #ifndef ACCUMULATE_OUTGOING_ARGS
366 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
367 if (HAVE_call_pop && HAVE_call_value_pop
368 && (RETURN_POPS_ARGS (fndecl, funtype, stack_size) > 0
371 rtx n_pop = GEN_INT (RETURN_POPS_ARGS (fndecl, funtype, stack_size));
374 /* If this subroutine pops its own args, record that in the call insn
375 if possible, for the sake of frame pointer elimination. */
378 pat = gen_call_value_pop (valreg,
379 gen_rtx (MEM, FUNCTION_MODE, funexp),
380 stack_size_rtx, next_arg_reg, n_pop);
382 pat = gen_call_pop (gen_rtx (MEM, FUNCTION_MODE, funexp),
383 stack_size_rtx, next_arg_reg, n_pop);
385 emit_call_insn (pat);
392 #if defined (HAVE_call) && defined (HAVE_call_value)
393 if (HAVE_call && HAVE_call_value)
396 emit_call_insn (gen_call_value (valreg,
397 gen_rtx (MEM, FUNCTION_MODE, funexp),
398 stack_size_rtx, next_arg_reg,
401 emit_call_insn (gen_call (gen_rtx (MEM, FUNCTION_MODE, funexp),
402 stack_size_rtx, next_arg_reg,
403 struct_value_size_rtx));
409 /* Find the CALL insn we just emitted. */
410 for (call_insn = get_last_insn ();
411 call_insn && GET_CODE (call_insn) != CALL_INSN;
412 call_insn = PREV_INSN (call_insn))
418 /* Put the register usage information on the CALL. If there is already
419 some usage information, put ours at the end. */
420 if (CALL_INSN_FUNCTION_USAGE (call_insn))
424 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
425 link = XEXP (link, 1))
428 XEXP (link, 1) = call_fusage;
431 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
433 /* If this is a const call, then set the insn's unchanging bit. */
435 CONST_CALL_P (call_insn) = 1;
437 /* Restore this now, so that we do defer pops for this call's args
438 if the context of the call as a whole permits. */
439 inhibit_defer_pop = old_inhibit_defer_pop;
441 #ifndef ACCUMULATE_OUTGOING_ARGS
442 /* If returning from the subroutine does not automatically pop the args,
443 we need an instruction to pop them sooner or later.
444 Perhaps do it now; perhaps just record how much space to pop later.
446 If returning from the subroutine does pop the args, indicate that the
447 stack pointer will be changed. */
449 if (stack_size != 0 && RETURN_POPS_ARGS (fndecl, funtype, stack_size) > 0)
452 CALL_INSN_FUNCTION_USAGE (call_insn) =
453 gen_rtx (EXPR_LIST, VOIDmode,
454 gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx),
455 CALL_INSN_FUNCTION_USAGE (call_insn));
456 stack_size -= RETURN_POPS_ARGS (fndecl, funtype, stack_size);
457 stack_size_rtx = GEN_INT (stack_size);
462 if (flag_defer_pop && inhibit_defer_pop == 0 && !is_const)
463 pending_stack_adjust += stack_size;
465 adjust_stack (stack_size_rtx);
470 /* Generate all the code for a function call
471 and return an rtx for its value.
472 Store the value in TARGET (specified as an rtx) if convenient.
473 If the value is stored in TARGET then TARGET is returned.
474 If IGNORE is nonzero, then we ignore the value of the function call. */
477 expand_call (exp, target, ignore)
482 /* List of actual parameters. */
483 tree actparms = TREE_OPERAND (exp, 1);
484 /* RTX for the function to be called. */
486 /* Tree node for the function to be called (not the address!). */
488 /* Data type of the function. */
490 /* Declaration of the function being called,
491 or 0 if the function is computed (not known by name). */
495 /* Register in which non-BLKmode value will be returned,
496 or 0 if no value or if value is BLKmode. */
498 /* Address where we should return a BLKmode value;
499 0 if value not BLKmode. */
500 rtx structure_value_addr = 0;
501 /* Nonzero if that address is being passed by treating it as
502 an extra, implicit first parameter. Otherwise,
503 it is passed by being copied directly into struct_value_rtx. */
504 int structure_value_addr_parm = 0;
505 /* Size of aggregate value wanted, or zero if none wanted
506 or if we are using the non-reentrant PCC calling convention
507 or expecting the value in registers. */
508 int struct_value_size = 0;
509 /* Nonzero if called function returns an aggregate in memory PCC style,
510 by returning the address of where to find it. */
511 int pcc_struct_value = 0;
513 /* Number of actual parameters in this call, including struct value addr. */
515 /* Number of named args. Args after this are anonymous ones
516 and they must all go on the stack. */
518 /* Count arg position in order args appear. */
521 /* Vector of information about each argument.
522 Arguments are numbered in the order they will be pushed,
523 not the order they are written. */
524 struct arg_data *args;
526 /* Total size in bytes of all the stack-parms scanned so far. */
527 struct args_size args_size;
528 /* Size of arguments before any adjustments (such as rounding). */
529 struct args_size original_args_size;
530 /* Data on reg parms scanned so far. */
531 CUMULATIVE_ARGS args_so_far;
532 /* Nonzero if a reg parm has been scanned. */
534 /* Nonzero if this is an indirect function call. */
535 int current_call_is_indirect = 0;
537 /* Nonzero if we must avoid push-insns in the args for this call.
538 If stack space is allocated for register parameters, but not by the
539 caller, then it is preallocated in the fixed part of the stack frame.
540 So the entire argument block must then be preallocated (i.e., we
541 ignore PUSH_ROUNDING in that case). */
543 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
544 int must_preallocate = 1;
547 int must_preallocate = 0;
549 int must_preallocate = 1;
553 /* Size of the stack reserved for parameter registers. */
554 int reg_parm_stack_space = 0;
556 /* 1 if scanning parms front to back, -1 if scanning back to front. */
558 /* Address of space preallocated for stack parms
559 (on machines that lack push insns), or 0 if space not preallocated. */
562 /* Nonzero if it is plausible that this is a call to alloca. */
564 /* Nonzero if this is a call to setjmp or a related function. */
566 /* Nonzero if this is a call to `longjmp'. */
568 /* Nonzero if this is a call to an inline function. */
569 int is_integrable = 0;
570 /* Nonzero if this is a call to a `const' function.
571 Note that only explicitly named functions are handled as `const' here. */
573 /* Nonzero if this is a call to a `volatile' function. */
575 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
576 /* Define the boundary of the register parm stack space that needs to be
578 int low_to_save = -1, high_to_save;
579 rtx save_area = 0; /* Place that it is saved */
582 #ifdef ACCUMULATE_OUTGOING_ARGS
583 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
584 char *initial_stack_usage_map = stack_usage_map;
587 rtx old_stack_level = 0;
588 int old_pending_adj = 0;
589 int old_stack_arg_under_construction;
590 int old_inhibit_defer_pop = inhibit_defer_pop;
591 tree old_cleanups = cleanups_this_call;
596 /* See if we can find a DECL-node for the actual function.
597 As a result, decide whether this is a call to an integrable function. */
599 p = TREE_OPERAND (exp, 0);
600 if (TREE_CODE (p) == ADDR_EXPR)
602 fndecl = TREE_OPERAND (p, 0);
603 if (TREE_CODE (fndecl) != FUNCTION_DECL)
608 && fndecl != current_function_decl
609 && DECL_INLINE (fndecl)
610 && DECL_SAVED_INSNS (fndecl))
612 else if (! TREE_ADDRESSABLE (fndecl))
614 /* In case this function later becomes inlinable,
615 record that there was already a non-inline call to it.
617 Use abstraction instead of setting TREE_ADDRESSABLE
619 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline)
621 warning_with_decl (fndecl, "can't inline call to `%s'");
622 warning ("called from here");
624 mark_addressable (fndecl);
627 if (TREE_READONLY (fndecl) && ! TREE_THIS_VOLATILE (fndecl)
628 && TYPE_MODE (TREE_TYPE (exp)) != VOIDmode)
631 if (TREE_THIS_VOLATILE (fndecl))
636 /* If we don't have specific function to call, see if we have a
637 constant or `noreturn' function from the type. */
640 is_const = TREE_READONLY (TREE_TYPE (TREE_TYPE (p)));
641 is_volatile = TREE_THIS_VOLATILE (TREE_TYPE (TREE_TYPE (p)));
644 #ifdef REG_PARM_STACK_SPACE
645 #ifdef MAYBE_REG_PARM_STACK_SPACE
646 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
648 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
652 /* Warn if this value is an aggregate type,
653 regardless of which calling convention we are using for it. */
654 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
655 warning ("function call has aggregate value");
657 /* Set up a place to return a structure. */
659 /* Cater to broken compilers. */
660 if (aggregate_value_p (exp))
662 /* This call returns a big structure. */
665 #ifdef PCC_STATIC_STRUCT_RETURN
667 pcc_struct_value = 1;
668 /* Easier than making that case work right. */
671 /* In case this is a static function, note that it has been
673 if (! TREE_ADDRESSABLE (fndecl))
674 mark_addressable (fndecl);
678 #else /* not PCC_STATIC_STRUCT_RETURN */
680 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
682 if (target && GET_CODE (target) == MEM)
683 structure_value_addr = XEXP (target, 0);
686 /* Assign a temporary on the stack to hold the value. */
688 /* For variable-sized objects, we must be called with a target
689 specified. If we were to allocate space on the stack here,
690 we would have no way of knowing when to free it. */
692 if (struct_value_size < 0)
696 = XEXP (assign_stack_temp (BLKmode, struct_value_size, 1), 0);
697 MEM_IN_STRUCT_P (structure_value_addr)
698 = AGGREGATE_TYPE_P (TREE_TYPE (exp));
702 #endif /* not PCC_STATIC_STRUCT_RETURN */
705 /* If called function is inline, try to integrate it. */
710 rtx before_call = get_last_insn ();
712 temp = expand_inline_function (fndecl, actparms, target,
713 ignore, TREE_TYPE (exp),
714 structure_value_addr);
716 /* If inlining succeeded, return. */
717 if ((HOST_WIDE_INT) temp != -1)
719 if (flag_short_temps)
721 /* Perform all cleanups needed for the arguments of this
722 call (i.e. destructors in C++). It is ok if these
723 destructors clobber RETURN_VALUE_REG, because the
724 only time we care about this is when TARGET is that
725 register. But in C++, we take care to never return
726 that register directly. */
727 expand_cleanups_to (old_cleanups);
730 #ifdef ACCUMULATE_OUTGOING_ARGS
731 /* If the outgoing argument list must be preserved, push
732 the stack before executing the inlined function if it
735 for (i = reg_parm_stack_space - 1; i >= 0; i--)
736 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
739 if (stack_arg_under_construction || i >= 0)
741 rtx insn = NEXT_INSN (before_call), seq;
743 /* Look for a call in the inline function code.
744 If OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl)) is
745 nonzero then there is a call and it is not necessary
746 to scan the insns. */
748 if (OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl)) == 0)
749 for (; insn; insn = NEXT_INSN (insn))
750 if (GET_CODE (insn) == CALL_INSN)
755 /* Reserve enough stack space so that the largest
756 argument list of any function call in the inline
757 function does not overlap the argument list being
758 evaluated. This is usually an overestimate because
759 allocate_dynamic_stack_space reserves space for an
760 outgoing argument list in addition to the requested
761 space, but there is no way to ask for stack space such
762 that an argument list of a certain length can be
763 safely constructed. */
765 int adjust = OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl));
766 #ifdef REG_PARM_STACK_SPACE
767 /* Add the stack space reserved for register arguments
768 in the inline function. What is really needed is the
769 largest value of reg_parm_stack_space in the inline
770 function, but that is not available. Using the current
771 value of reg_parm_stack_space is wrong, but gives
772 correct results on all supported machines. */
773 adjust += reg_parm_stack_space;
776 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
777 allocate_dynamic_stack_space (GEN_INT (adjust),
778 NULL_RTX, BITS_PER_UNIT);
781 emit_insns_before (seq, NEXT_INSN (before_call));
782 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
787 /* If the result is equivalent to TARGET, return TARGET to simplify
788 checks in store_expr. They can be equivalent but not equal in the
789 case of a function that returns BLKmode. */
790 if (temp != target && rtx_equal_p (temp, target))
795 /* If inlining failed, mark FNDECL as needing to be compiled
796 separately after all. If function was declared inline,
798 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
799 && ! TREE_ADDRESSABLE (fndecl))
801 warning_with_decl (fndecl, "inlining failed in call to `%s'");
802 warning ("called from here");
804 mark_addressable (fndecl);
807 /* When calling a const function, we must pop the stack args right away,
808 so that the pop is deleted or moved with the call. */
812 function_call_count++;
814 if (fndecl && DECL_NAME (fndecl))
815 name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
817 /* On some machines (such as the PA) indirect calls have a different
818 calling convention than normal calls. FUNCTION_ARG in the target
819 description can look at current_call_is_indirect to determine which
820 calling convention to use. */
821 current_call_is_indirect = (fndecl == 0);
823 = TREE_CODE (TREE_OPERAND (exp, 0)) == NON_LVALUE_EXPR ? 1 : 0;
827 /* Unless it's a call to a specific function that isn't alloca,
828 if it has one argument, we must assume it might be alloca. */
831 (!(fndecl != 0 && strcmp (name, "alloca"))
833 && TREE_CHAIN (actparms) == 0);
835 /* We assume that alloca will always be called by name. It
836 makes no sense to pass it as a pointer-to-function to
837 anything that does not understand its behavior. */
839 (name && ((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
841 && ! strcmp (name, "alloca"))
842 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
844 && ! strcmp (name, "__builtin_alloca"))));
847 /* See if this is a call to a function that can return more than once
848 or a call to longjmp. */
853 if (name != 0 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 15)
857 /* Disregard prefix _, __ or __x. */
860 if (name[1] == '_' && name[2] == 'x')
862 else if (name[1] == '_')
872 && (! strcmp (tname, "setjmp")
873 || ! strcmp (tname, "setjmp_syscall")))
875 && ! strcmp (tname, "sigsetjmp"))
877 && ! strcmp (tname, "savectx")));
879 && ! strcmp (tname, "siglongjmp"))
882 else if ((tname[0] == 'q' && tname[1] == 's'
883 && ! strcmp (tname, "qsetjmp"))
884 || (tname[0] == 'v' && tname[1] == 'f'
885 && ! strcmp (tname, "vfork")))
888 else if (tname[0] == 'l' && tname[1] == 'o'
889 && ! strcmp (tname, "longjmp"))
894 current_function_calls_alloca = 1;
896 /* Don't let pending stack adjusts add up to too much.
897 Also, do all pending adjustments now
898 if there is any chance this might be a call to alloca. */
900 if (pending_stack_adjust >= 32
901 || (pending_stack_adjust > 0 && may_be_alloca))
902 do_pending_stack_adjust ();
904 /* Operand 0 is a pointer-to-function; get the type of the function. */
905 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
906 if (TREE_CODE (funtype) != POINTER_TYPE)
908 funtype = TREE_TYPE (funtype);
910 /* Push the temporary stack slot level so that we can free any temporaries
914 /* Start updating where the next arg would go. */
915 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX);
917 /* If struct_value_rtx is 0, it means pass the address
918 as if it were an extra parameter. */
919 if (structure_value_addr && struct_value_rtx == 0)
921 /* If structure_value_addr is a REG other than
922 virtual_outgoing_args_rtx, we can use always use it. If it
923 is not a REG, we must always copy it into a register.
924 If it is virtual_outgoing_args_rtx, we must copy it to another
925 register in some cases. */
926 rtx temp = (GET_CODE (structure_value_addr) != REG
927 #ifdef ACCUMULATE_OUTGOING_ARGS
928 || (stack_arg_under_construction
929 && structure_value_addr == virtual_outgoing_args_rtx)
931 ? copy_addr_to_reg (structure_value_addr)
932 : structure_value_addr);
935 = tree_cons (error_mark_node,
936 make_tree (build_pointer_type (TREE_TYPE (funtype)),
939 structure_value_addr_parm = 1;
942 /* Count the arguments and set NUM_ACTUALS. */
943 for (p = actparms, i = 0; p; p = TREE_CHAIN (p)) i++;
946 /* Compute number of named args.
947 Normally, don't include the last named arg if anonymous args follow.
948 We do include the last named arg if STRICT_ARGUMENT_NAMING is defined.
949 (If no anonymous args follow, the result of list_length is actually
950 one too large. This is harmless.)
952 If SETUP_INCOMING_VARARGS is defined and STRICT_ARGUMENT_NAMING is not,
953 this machine will be able to place unnamed args that were passed in
954 registers into the stack. So treat all args as named. This allows the
955 insns emitting for a specific argument list to be independent of the
956 function declaration.
958 If SETUP_INCOMING_VARARGS is not defined, we do not have any reliable
959 way to pass unnamed args in registers, so we must force them into
961 #if !defined(SETUP_INCOMING_VARARGS) || defined(STRICT_ARGUMENT_NAMING)
962 if (TYPE_ARG_TYPES (funtype) != 0)
964 = (list_length (TYPE_ARG_TYPES (funtype))
965 #ifndef STRICT_ARGUMENT_NAMING
966 /* Don't include the last named arg. */
969 /* Count the struct value address, if it is passed as a parm. */
970 + structure_value_addr_parm);
973 /* If we know nothing, treat all args as named. */
974 n_named_args = num_actuals;
976 /* Make a vector to hold all the information about each arg. */
977 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
978 bzero ((char *) args, num_actuals * sizeof (struct arg_data));
980 args_size.constant = 0;
983 /* In this loop, we consider args in the order they are written.
984 We fill up ARGS from the front or from the back if necessary
985 so that in any case the first arg to be pushed ends up at the front. */
987 #ifdef PUSH_ARGS_REVERSED
988 i = num_actuals - 1, inc = -1;
989 /* In this case, must reverse order of args
990 so that we compute and push the last arg first. */
995 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
996 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
998 tree type = TREE_TYPE (TREE_VALUE (p));
1000 enum machine_mode mode;
1002 args[i].tree_value = TREE_VALUE (p);
1004 /* Replace erroneous argument with constant zero. */
1005 if (type == error_mark_node || TYPE_SIZE (type) == 0)
1006 args[i].tree_value = integer_zero_node, type = integer_type_node;
1008 /* If TYPE is a transparent union, pass things the way we would
1009 pass the first field of the union. We have already verified that
1010 the modes are the same. */
1011 if (TYPE_TRANSPARENT_UNION (type))
1012 type = TREE_TYPE (TYPE_FIELDS (type));
1014 /* Decide where to pass this arg.
1016 args[i].reg is nonzero if all or part is passed in registers.
1018 args[i].partial is nonzero if part but not all is passed in registers,
1019 and the exact value says how many words are passed in registers.
1021 args[i].pass_on_stack is nonzero if the argument must at least be
1022 computed on the stack. It may then be loaded back into registers
1023 if args[i].reg is nonzero.
1025 These decisions are driven by the FUNCTION_... macros and must agree
1026 with those made by function.c. */
1028 /* See if this argument should be passed by invisible reference. */
1029 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1030 && contains_placeholder_p (TYPE_SIZE (type)))
1031 || TREE_ADDRESSABLE (type)
1032 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1033 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, TYPE_MODE (type),
1034 type, argpos < n_named_args)
1038 #ifdef FUNCTION_ARG_CALLEE_COPIES
1039 if (FUNCTION_ARG_CALLEE_COPIES (args_so_far, TYPE_MODE (type), type,
1040 argpos < n_named_args)
1041 /* If it's in a register, we must make a copy of it too. */
1042 /* ??? Is this a sufficient test? Is there a better one? */
1043 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1044 && REG_P (DECL_RTL (args[i].tree_value))))
1046 args[i].tree_value = build1 (ADDR_EXPR,
1047 build_pointer_type (type),
1048 args[i].tree_value);
1049 type = build_pointer_type (type);
1054 /* We make a copy of the object and pass the address to the
1055 function being called. */
1058 if (TYPE_SIZE (type) == 0
1059 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
1061 /* This is a variable-sized object. Make space on the stack
1063 rtx size_rtx = expr_size (TREE_VALUE (p));
1065 if (old_stack_level == 0)
1067 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1068 old_pending_adj = pending_stack_adjust;
1069 pending_stack_adjust = 0;
1072 copy = gen_rtx (MEM, BLKmode,
1073 allocate_dynamic_stack_space (size_rtx,
1075 TYPE_ALIGN (type)));
1079 int size = int_size_in_bytes (type);
1080 copy = assign_stack_temp (TYPE_MODE (type), size, 0);
1083 MEM_IN_STRUCT_P (copy) = AGGREGATE_TYPE_P (type);
1085 store_expr (args[i].tree_value, copy, 0);
1087 args[i].tree_value = build1 (ADDR_EXPR,
1088 build_pointer_type (type),
1089 make_tree (type, copy));
1090 type = build_pointer_type (type);
1094 mode = TYPE_MODE (type);
1095 unsignedp = TREE_UNSIGNED (type);
1097 #ifdef PROMOTE_FUNCTION_ARGS
1098 mode = promote_mode (type, mode, &unsignedp, 1);
1101 args[i].unsignedp = unsignedp;
1102 args[i].mode = mode;
1103 args[i].reg = FUNCTION_ARG (args_so_far, mode, type,
1104 argpos < n_named_args);
1105 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1108 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, type,
1109 argpos < n_named_args);
1112 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1114 /* If FUNCTION_ARG returned an (expr_list (nil) FOO), it means that
1115 we are to pass this arg in the register(s) designated by FOO, but
1116 also to pass it in the stack. */
1117 if (args[i].reg && GET_CODE (args[i].reg) == EXPR_LIST
1118 && XEXP (args[i].reg, 0) == 0)
1119 args[i].pass_on_stack = 1, args[i].reg = XEXP (args[i].reg, 1);
1121 /* If this is an addressable type, we must preallocate the stack
1122 since we must evaluate the object into its final location.
1124 If this is to be passed in both registers and the stack, it is simpler
1126 if (TREE_ADDRESSABLE (type)
1127 || (args[i].pass_on_stack && args[i].reg != 0))
1128 must_preallocate = 1;
1130 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1131 we cannot consider this function call constant. */
1132 if (TREE_ADDRESSABLE (type))
1135 /* Compute the stack-size of this argument. */
1136 if (args[i].reg == 0 || args[i].partial != 0
1137 #ifdef REG_PARM_STACK_SPACE
1138 || reg_parm_stack_space > 0
1140 || args[i].pass_on_stack)
1141 locate_and_pad_parm (mode, type,
1142 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1147 fndecl, &args_size, &args[i].offset,
1150 #ifndef ARGS_GROW_DOWNWARD
1151 args[i].slot_offset = args_size;
1154 #ifndef REG_PARM_STACK_SPACE
1155 /* If a part of the arg was put into registers,
1156 don't include that part in the amount pushed. */
1157 if (! args[i].pass_on_stack)
1158 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1159 / (PARM_BOUNDARY / BITS_PER_UNIT)
1160 * (PARM_BOUNDARY / BITS_PER_UNIT));
1163 /* Update ARGS_SIZE, the total stack space for args so far. */
1165 args_size.constant += args[i].size.constant;
1166 if (args[i].size.var)
1168 ADD_PARM_SIZE (args_size, args[i].size.var);
1171 /* Since the slot offset points to the bottom of the slot,
1172 we must record it after incrementing if the args grow down. */
1173 #ifdef ARGS_GROW_DOWNWARD
1174 args[i].slot_offset = args_size;
1176 args[i].slot_offset.constant = -args_size.constant;
1179 SUB_PARM_SIZE (args[i].slot_offset, args_size.var);
1183 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1184 have been used, etc. */
1186 FUNCTION_ARG_ADVANCE (args_so_far, TYPE_MODE (type), type,
1187 argpos < n_named_args);
1190 #ifdef FINAL_REG_PARM_STACK_SPACE
1191 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
1195 /* Compute the actual size of the argument block required. The variable
1196 and constant sizes must be combined, the size may have to be rounded,
1197 and there may be a minimum required size. */
1199 original_args_size = args_size;
1202 /* If this function requires a variable-sized argument list, don't try to
1203 make a cse'able block for this call. We may be able to do this
1204 eventually, but it is too complicated to keep track of what insns go
1205 in the cse'able block and which don't. */
1208 must_preallocate = 1;
1210 args_size.var = ARGS_SIZE_TREE (args_size);
1211 args_size.constant = 0;
1213 #ifdef STACK_BOUNDARY
1214 if (STACK_BOUNDARY != BITS_PER_UNIT)
1215 args_size.var = round_up (args_size.var, STACK_BYTES);
1218 #ifdef REG_PARM_STACK_SPACE
1219 if (reg_parm_stack_space > 0)
1222 = size_binop (MAX_EXPR, args_size.var,
1223 size_int (REG_PARM_STACK_SPACE (fndecl)));
1225 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1226 /* The area corresponding to register parameters is not to count in
1227 the size of the block we need. So make the adjustment. */
1229 = size_binop (MINUS_EXPR, args_size.var,
1230 size_int (reg_parm_stack_space));
1237 #ifdef STACK_BOUNDARY
1238 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
1239 / STACK_BYTES) * STACK_BYTES);
1242 #ifdef REG_PARM_STACK_SPACE
1243 args_size.constant = MAX (args_size.constant,
1244 reg_parm_stack_space);
1245 #ifdef MAYBE_REG_PARM_STACK_SPACE
1246 if (reg_parm_stack_space == 0)
1247 args_size.constant = 0;
1249 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1250 args_size.constant -= reg_parm_stack_space;
1255 /* See if we have or want to preallocate stack space.
1257 If we would have to push a partially-in-regs parm
1258 before other stack parms, preallocate stack space instead.
1260 If the size of some parm is not a multiple of the required stack
1261 alignment, we must preallocate.
1263 If the total size of arguments that would otherwise create a copy in
1264 a temporary (such as a CALL) is more than half the total argument list
1265 size, preallocation is faster.
1267 Another reason to preallocate is if we have a machine (like the m88k)
1268 where stack alignment is required to be maintained between every
1269 pair of insns, not just when the call is made. However, we assume here
1270 that such machines either do not have push insns (and hence preallocation
1271 would occur anyway) or the problem is taken care of with
1274 if (! must_preallocate)
1276 int partial_seen = 0;
1277 int copy_to_evaluate_size = 0;
1279 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1281 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1283 else if (partial_seen && args[i].reg == 0)
1284 must_preallocate = 1;
1286 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1287 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1288 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1289 || TREE_CODE (args[i].tree_value) == COND_EXPR
1290 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1291 copy_to_evaluate_size
1292 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1295 if (copy_to_evaluate_size * 2 >= args_size.constant
1296 && args_size.constant > 0)
1297 must_preallocate = 1;
1300 /* If the structure value address will reference the stack pointer, we must
1301 stabilize it. We don't need to do this if we know that we are not going
1302 to adjust the stack pointer in processing this call. */
1304 if (structure_value_addr
1305 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
1306 || reg_mentioned_p (virtual_outgoing_args_rtx, structure_value_addr))
1308 #ifndef ACCUMULATE_OUTGOING_ARGS
1309 || args_size.constant
1312 structure_value_addr = copy_to_reg (structure_value_addr);
1314 /* If this function call is cse'able, precompute all the parameters.
1315 Note that if the parameter is constructed into a temporary, this will
1316 cause an additional copy because the parameter will be constructed
1317 into a temporary location and then copied into the outgoing arguments.
1318 If a parameter contains a call to alloca and this function uses the
1319 stack, precompute the parameter. */
1321 /* If we preallocated the stack space, and some arguments must be passed
1322 on the stack, then we must precompute any parameter which contains a
1323 function call which will store arguments on the stack.
1324 Otherwise, evaluating the parameter may clobber previous parameters
1325 which have already been stored into the stack. */
1327 for (i = 0; i < num_actuals; i++)
1329 || ((args_size.var != 0 || args_size.constant != 0)
1330 && calls_function (args[i].tree_value, 1))
1331 || (must_preallocate && (args_size.var != 0 || args_size.constant != 0)
1332 && calls_function (args[i].tree_value, 0)))
1334 /* If this is an addressable type, we cannot pre-evaluate it. */
1335 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1340 args[i].initial_value = args[i].value
1341 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1343 preserve_temp_slots (args[i].value);
1346 /* ANSI doesn't require a sequence point here,
1347 but PCC has one, so this will avoid some problems. */
1350 args[i].initial_value = args[i].value
1351 = protect_from_queue (args[i].initial_value, 0);
1353 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) != args[i].mode)
1355 = convert_modes (args[i].mode,
1356 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1357 args[i].value, args[i].unsignedp);
1360 /* Now we are about to start emitting insns that can be deleted
1361 if a libcall is deleted. */
1365 /* If we have no actual push instructions, or shouldn't use them,
1366 make space for all args right now. */
1368 if (args_size.var != 0)
1370 if (old_stack_level == 0)
1372 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1373 old_pending_adj = pending_stack_adjust;
1374 pending_stack_adjust = 0;
1375 #ifdef ACCUMULATE_OUTGOING_ARGS
1376 /* stack_arg_under_construction says whether a stack arg is
1377 being constructed at the old stack level. Pushing the stack
1378 gets a clean outgoing argument block. */
1379 old_stack_arg_under_construction = stack_arg_under_construction;
1380 stack_arg_under_construction = 0;
1383 argblock = push_block (ARGS_SIZE_RTX (args_size), 0, 0);
1387 /* Note that we must go through the motions of allocating an argument
1388 block even if the size is zero because we may be storing args
1389 in the area reserved for register arguments, which may be part of
1392 int needed = args_size.constant;
1394 /* Store the maximum argument space used. It will be pushed by the
1395 prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow checking). */
1397 if (needed > current_function_outgoing_args_size)
1398 current_function_outgoing_args_size = needed;
1400 if (must_preallocate)
1402 #ifdef ACCUMULATE_OUTGOING_ARGS
1403 /* Since the stack pointer will never be pushed, it is possible for
1404 the evaluation of a parm to clobber something we have already
1405 written to the stack. Since most function calls on RISC machines
1406 do not use the stack, this is uncommon, but must work correctly.
1408 Therefore, we save any area of the stack that was already written
1409 and that we are using. Here we set up to do this by making a new
1410 stack usage map from the old one. The actual save will be done
1413 Another approach might be to try to reorder the argument
1414 evaluations to avoid this conflicting stack usage. */
1416 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1417 /* Since we will be writing into the entire argument area, the
1418 map must be allocated for its entire size, not just the part that
1419 is the responsibility of the caller. */
1420 needed += reg_parm_stack_space;
1423 #ifdef ARGS_GROW_DOWNWARD
1424 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
1427 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
1430 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
1432 if (initial_highest_arg_in_use)
1433 bcopy (initial_stack_usage_map, stack_usage_map,
1434 initial_highest_arg_in_use);
1436 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
1437 bzero (&stack_usage_map[initial_highest_arg_in_use],
1438 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
1441 /* The address of the outgoing argument list must not be copied to a
1442 register here, because argblock would be left pointing to the
1443 wrong place after the call to allocate_dynamic_stack_space below.
1446 argblock = virtual_outgoing_args_rtx;
1448 #else /* not ACCUMULATE_OUTGOING_ARGS */
1449 if (inhibit_defer_pop == 0)
1451 /* Try to reuse some or all of the pending_stack_adjust
1452 to get this space. Maybe we can avoid any pushing. */
1453 if (needed > pending_stack_adjust)
1455 needed -= pending_stack_adjust;
1456 pending_stack_adjust = 0;
1460 pending_stack_adjust -= needed;
1464 /* Special case this because overhead of `push_block' in this
1465 case is non-trivial. */
1467 argblock = virtual_outgoing_args_rtx;
1469 argblock = push_block (GEN_INT (needed), 0, 0);
1471 /* We only really need to call `copy_to_reg' in the case where push
1472 insns are going to be used to pass ARGBLOCK to a function
1473 call in ARGS. In that case, the stack pointer changes value
1474 from the allocation point to the call point, and hence
1475 the value of VIRTUAL_OUTGOING_ARGS_RTX changes as well.
1476 But might as well always do it. */
1477 argblock = copy_to_reg (argblock);
1478 #endif /* not ACCUMULATE_OUTGOING_ARGS */
1482 #ifdef ACCUMULATE_OUTGOING_ARGS
1483 /* The save/restore code in store_one_arg handles all cases except one:
1484 a constructor call (including a C function returning a BLKmode struct)
1485 to initialize an argument. */
1486 if (stack_arg_under_construction)
1488 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1489 rtx push_size = GEN_INT (reg_parm_stack_space + args_size.constant);
1491 rtx push_size = GEN_INT (args_size.constant);
1493 if (old_stack_level == 0)
1495 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1496 old_pending_adj = pending_stack_adjust;
1497 pending_stack_adjust = 0;
1498 /* stack_arg_under_construction says whether a stack arg is
1499 being constructed at the old stack level. Pushing the stack
1500 gets a clean outgoing argument block. */
1501 old_stack_arg_under_construction = stack_arg_under_construction;
1502 stack_arg_under_construction = 0;
1503 /* Make a new map for the new argument list. */
1504 stack_usage_map = (char *)alloca (highest_outgoing_arg_in_use);
1505 bzero (stack_usage_map, highest_outgoing_arg_in_use);
1506 highest_outgoing_arg_in_use = 0;
1508 allocate_dynamic_stack_space (push_size, NULL_RTX, BITS_PER_UNIT);
1510 /* If argument evaluation might modify the stack pointer, copy the
1511 address of the argument list to a register. */
1512 for (i = 0; i < num_actuals; i++)
1513 if (args[i].pass_on_stack)
1515 argblock = copy_addr_to_reg (argblock);
1521 /* If we preallocated stack space, compute the address of each argument.
1522 We need not ensure it is a valid memory address here; it will be
1523 validized when it is used. */
1526 rtx arg_reg = argblock;
1529 if (GET_CODE (argblock) == PLUS)
1530 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1532 for (i = 0; i < num_actuals; i++)
1534 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1535 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1538 /* Skip this parm if it will not be passed on the stack. */
1539 if (! args[i].pass_on_stack && args[i].reg != 0)
1542 if (GET_CODE (offset) == CONST_INT)
1543 addr = plus_constant (arg_reg, INTVAL (offset));
1545 addr = gen_rtx (PLUS, Pmode, arg_reg, offset);
1547 addr = plus_constant (addr, arg_offset);
1548 args[i].stack = gen_rtx (MEM, args[i].mode, addr);
1549 MEM_IN_STRUCT_P (args[i].stack)
1550 = AGGREGATE_TYPE_P (TREE_TYPE (args[i].tree_value));
1552 if (GET_CODE (slot_offset) == CONST_INT)
1553 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1555 addr = gen_rtx (PLUS, Pmode, arg_reg, slot_offset);
1557 addr = plus_constant (addr, arg_offset);
1558 args[i].stack_slot = gen_rtx (MEM, args[i].mode, addr);
1562 #ifdef PUSH_ARGS_REVERSED
1563 #ifdef STACK_BOUNDARY
1564 /* If we push args individually in reverse order, perform stack alignment
1565 before the first push (the last arg). */
1567 anti_adjust_stack (GEN_INT (args_size.constant
1568 - original_args_size.constant));
1572 /* Don't try to defer pops if preallocating, not even from the first arg,
1573 since ARGBLOCK probably refers to the SP. */
1577 /* Get the function to call, in the form of RTL. */
1580 /* If this is the first use of the function, see if we need to
1581 make an external definition for it. */
1582 if (! TREE_USED (fndecl))
1584 assemble_external (fndecl);
1585 TREE_USED (fndecl) = 1;
1588 /* Get a SYMBOL_REF rtx for the function address. */
1589 funexp = XEXP (DECL_RTL (fndecl), 0);
1592 /* Generate an rtx (probably a pseudo-register) for the address. */
1595 funexp = expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1596 pop_temp_slots (); /* FUNEXP can't be BLKmode */
1600 /* Figure out the register where the value, if any, will come back. */
1602 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
1603 && ! structure_value_addr)
1605 if (pcc_struct_value)
1606 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
1609 valreg = hard_function_value (TREE_TYPE (exp), fndecl);
1612 /* Precompute all register parameters. It isn't safe to compute anything
1613 once we have started filling any specific hard regs. */
1615 for (i = 0; i < num_actuals; i++)
1616 if (args[i].reg != 0 && ! args[i].pass_on_stack)
1620 if (args[i].value == 0)
1623 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
1625 preserve_temp_slots (args[i].value);
1628 /* ANSI doesn't require a sequence point here,
1629 but PCC has one, so this will avoid some problems. */
1633 /* If we are to promote the function arg to a wider mode,
1636 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
1638 = convert_modes (args[i].mode,
1639 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1640 args[i].value, args[i].unsignedp);
1642 /* If the value is expensive, and we are inside an appropriately
1643 short loop, put the value into a pseudo and then put the pseudo
1646 For small register classes, also do this if this call uses
1647 register parameters. This is to avoid reload conflicts while
1648 loading the parameters registers. */
1650 if ((! (GET_CODE (args[i].value) == REG
1651 || (GET_CODE (args[i].value) == SUBREG
1652 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
1653 && args[i].mode != BLKmode
1654 && rtx_cost (args[i].value, SET) > 2
1655 #ifdef SMALL_REGISTER_CLASSES
1656 && (reg_parm_seen || preserve_subexpressions_p ())
1658 && preserve_subexpressions_p ()
1661 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
1664 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
1665 /* The argument list is the property of the called routine and it
1666 may clobber it. If the fixed area has been used for previous
1667 parameters, we must save and restore it.
1669 Here we compute the boundary of the that needs to be saved, if any. */
1671 #ifdef ARGS_GROW_DOWNWARD
1672 for (i = 0; i < reg_parm_stack_space + 1; i++)
1674 for (i = 0; i < reg_parm_stack_space; i++)
1677 if (i >= highest_outgoing_arg_in_use
1678 || stack_usage_map[i] == 0)
1681 if (low_to_save == -1)
1687 if (low_to_save >= 0)
1689 int num_to_save = high_to_save - low_to_save + 1;
1690 enum machine_mode save_mode
1691 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
1694 /* If we don't have the required alignment, must do this in BLKmode. */
1695 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
1696 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
1697 save_mode = BLKmode;
1699 stack_area = gen_rtx (MEM, save_mode,
1700 memory_address (save_mode,
1702 #ifdef ARGS_GROW_DOWNWARD
1703 plus_constant (argblock,
1706 plus_constant (argblock,
1710 if (save_mode == BLKmode)
1712 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
1713 MEM_IN_STRUCT_P (save_area) = 0;
1714 emit_block_move (validize_mem (save_area), stack_area,
1715 GEN_INT (num_to_save),
1716 PARM_BOUNDARY / BITS_PER_UNIT);
1720 save_area = gen_reg_rtx (save_mode);
1721 emit_move_insn (save_area, stack_area);
1727 /* Now store (and compute if necessary) all non-register parms.
1728 These come before register parms, since they can require block-moves,
1729 which could clobber the registers used for register parms.
1730 Parms which have partial registers are not stored here,
1731 but we do preallocate space here if they want that. */
1733 for (i = 0; i < num_actuals; i++)
1734 if (args[i].reg == 0 || args[i].pass_on_stack)
1735 store_one_arg (&args[i], argblock, may_be_alloca,
1736 args_size.var != 0, fndecl, reg_parm_stack_space);
1738 #ifdef STRICT_ALIGNMENT
1739 /* If we have a parm that is passed in registers but not in memory
1740 and whose alignment does not permit a direct copy into registers,
1741 make a group of pseudos that correspond to each register that we
1744 for (i = 0; i < num_actuals; i++)
1745 if (args[i].reg != 0 && ! args[i].pass_on_stack
1746 && args[i].mode == BLKmode
1747 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1748 < MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1750 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1751 int big_endian_correction = 0;
1753 args[i].n_aligned_regs
1754 = args[i].partial ? args[i].partial
1755 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1757 args[i].aligned_regs = (rtx *) alloca (sizeof (rtx)
1758 * args[i].n_aligned_regs);
1760 /* Structures smaller than a word are aligned to the least signifcant
1761 byte (to the right). On a BYTES_BIG_ENDIAN machine, this means we
1762 must skip the empty high order bytes when calculating the bit
1764 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
1765 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1767 for (j = 0; j < args[i].n_aligned_regs; j++)
1769 rtx reg = gen_reg_rtx (word_mode);
1770 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1771 int bitsize = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
1774 args[i].aligned_regs[j] = reg;
1776 /* Clobber REG and move each partword into it. Ensure we don't
1777 go past the end of the structure. Note that the loop below
1778 works because we've already verified that padding
1779 and endianness are compatible. */
1781 emit_insn (gen_rtx (CLOBBER, VOIDmode, reg));
1784 bitpos < BITS_PER_WORD && bytes > 0;
1785 bitpos += bitsize, bytes -= bitsize / BITS_PER_UNIT)
1787 int xbitpos = bitpos + big_endian_correction;
1789 store_bit_field (reg, bitsize, xbitpos, word_mode,
1790 extract_bit_field (word, bitsize, bitpos, 1,
1791 NULL_RTX, word_mode,
1793 bitsize / BITS_PER_UNIT,
1795 bitsize / BITS_PER_UNIT, BITS_PER_WORD);
1801 /* Now store any partially-in-registers parm.
1802 This is the last place a block-move can happen. */
1804 for (i = 0; i < num_actuals; i++)
1805 if (args[i].partial != 0 && ! args[i].pass_on_stack)
1806 store_one_arg (&args[i], argblock, may_be_alloca,
1807 args_size.var != 0, fndecl, reg_parm_stack_space);
1809 #ifndef PUSH_ARGS_REVERSED
1810 #ifdef STACK_BOUNDARY
1811 /* If we pushed args in forward order, perform stack alignment
1812 after pushing the last arg. */
1814 anti_adjust_stack (GEN_INT (args_size.constant
1815 - original_args_size.constant));
1819 /* If register arguments require space on the stack and stack space
1820 was not preallocated, allocate stack space here for arguments
1821 passed in registers. */
1822 #if ! defined(ACCUMULATE_OUTGOING_ARGS) && defined(OUTGOING_REG_PARM_STACK_SPACE)
1823 if (must_preallocate == 0 && reg_parm_stack_space > 0)
1824 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
1827 /* Pass the function the address in which to return a structure value. */
1828 if (structure_value_addr && ! structure_value_addr_parm)
1830 emit_move_insn (struct_value_rtx,
1832 force_operand (structure_value_addr,
1834 if (GET_CODE (struct_value_rtx) == REG)
1835 use_reg (&call_fusage, struct_value_rtx);
1838 funexp = prepare_call_address (funexp, fndecl, &call_fusage, reg_parm_seen);
1840 /* Now do the register loads required for any wholly-register parms or any
1841 parms which are passed both on the stack and in a register. Their
1842 expressions were already evaluated.
1844 Mark all register-parms as living through the call, putting these USE
1845 insns in the CALL_INSN_FUNCTION_USAGE field. */
1847 for (i = 0; i < num_actuals; i++)
1849 rtx list = args[i].reg;
1850 int partial = args[i].partial;
1857 /* Process each register that needs to get this arg. */
1858 if (GET_CODE (list) == EXPR_LIST)
1859 reg = XEXP (list, 0), list = XEXP (list, 1);
1861 reg = list, list = 0;
1863 /* Set to non-negative if must move a word at a time, even if just
1864 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1865 we just use a normal move insn. This value can be zero if the
1866 argument is a zero size structure with no fields. */
1867 nregs = (partial ? partial
1868 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1869 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1870 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1873 /* If simple case, just do move. If normal partial, store_one_arg
1874 has already loaded the register for us. In all other cases,
1875 load the register(s) from memory. */
1878 emit_move_insn (reg, args[i].value);
1880 #ifdef STRICT_ALIGNMENT
1881 /* If we have pre-computed the values to put in the registers in
1882 the case of non-aligned structures, copy them in now. */
1884 else if (args[i].n_aligned_regs != 0)
1885 for (j = 0; j < args[i].n_aligned_regs; j++)
1886 emit_move_insn (gen_rtx (REG, word_mode, REGNO (reg) + j),
1887 args[i].aligned_regs[j]);
1890 else if (args[i].partial == 0 || args[i].pass_on_stack)
1891 move_block_to_reg (REGNO (reg),
1892 validize_mem (args[i].value), nregs,
1896 use_reg (&call_fusage, reg);
1898 use_regs (&call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1900 /* PARTIAL referred only to the first register, so clear it for the
1906 /* Perform postincrements before actually calling the function. */
1909 /* All arguments and registers used for the call must be set up by now! */
1911 /* Generate the actual call instruction. */
1912 emit_call_1 (funexp, fndecl, funtype, args_size.constant, struct_value_size,
1913 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
1914 valreg, old_inhibit_defer_pop, call_fusage, is_const);
1916 /* If call is cse'able, make appropriate pair of reg-notes around it.
1917 Test valreg so we don't crash; may safely ignore `const'
1918 if return type is void. */
1919 if (is_const && valreg != 0)
1922 rtx temp = gen_reg_rtx (GET_MODE (valreg));
1925 /* Construct an "equal form" for the value which mentions all the
1926 arguments in order as well as the function name. */
1927 #ifdef PUSH_ARGS_REVERSED
1928 for (i = 0; i < num_actuals; i++)
1929 note = gen_rtx (EXPR_LIST, VOIDmode, args[i].initial_value, note);
1931 for (i = num_actuals - 1; i >= 0; i--)
1932 note = gen_rtx (EXPR_LIST, VOIDmode, args[i].initial_value, note);
1934 note = gen_rtx (EXPR_LIST, VOIDmode, funexp, note);
1936 insns = get_insns ();
1939 emit_libcall_block (insns, temp, valreg, note);
1945 /* Otherwise, just write out the sequence without a note. */
1946 rtx insns = get_insns ();
1952 /* For calls to `setjmp', etc., inform flow.c it should complain
1953 if nonvolatile values are live. */
1957 emit_note (name, NOTE_INSN_SETJMP);
1958 current_function_calls_setjmp = 1;
1962 current_function_calls_longjmp = 1;
1964 /* Notice functions that cannot return.
1965 If optimizing, insns emitted below will be dead.
1966 If not optimizing, they will exist, which is useful
1967 if the user uses the `return' command in the debugger. */
1969 if (is_volatile || is_longjmp)
1972 /* If value type not void, return an rtx for the value. */
1974 /* If there are cleanups to be called, don't use a hard reg as target. */
1975 if (cleanups_this_call != old_cleanups
1976 && target && REG_P (target)
1977 && REGNO (target) < FIRST_PSEUDO_REGISTER)
1980 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
1983 target = const0_rtx;
1985 else if (structure_value_addr)
1987 if (target == 0 || GET_CODE (target) != MEM)
1989 target = gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)),
1990 memory_address (TYPE_MODE (TREE_TYPE (exp)),
1991 structure_value_addr));
1992 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
1995 else if (pcc_struct_value)
1999 /* We used leave the value in the location that it is
2000 returned in, but that causes problems if it is used more
2001 than once in one expression. Rather than trying to track
2002 when a copy is required, we always copy when TARGET is
2003 not specified. This calling sequence is only used on
2004 a few machines and TARGET is usually nonzero. */
2005 if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
2007 target = assign_stack_temp (BLKmode,
2008 int_size_in_bytes (TREE_TYPE (exp)),
2011 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
2013 /* Save this temp slot around the pop below. */
2014 preserve_temp_slots (target);
2017 target = gen_reg_rtx (TYPE_MODE (TREE_TYPE (exp)));
2020 if (TYPE_MODE (TREE_TYPE (exp)) != BLKmode)
2021 emit_move_insn (target, gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)),
2022 copy_to_reg (valreg)));
2024 emit_block_move (target, gen_rtx (MEM, BLKmode, copy_to_reg (valreg)),
2026 TYPE_ALIGN (TREE_TYPE (exp)) / BITS_PER_UNIT);
2028 else if (target && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
2029 && GET_MODE (target) == GET_MODE (valreg))
2030 /* TARGET and VALREG cannot be equal at this point because the latter
2031 would not have REG_FUNCTION_VALUE_P true, while the former would if
2032 it were referring to the same register.
2034 If they refer to the same register, this move will be a no-op, except
2035 when function inlining is being done. */
2036 emit_move_insn (target, valreg);
2037 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
2039 /* Some machines (the PA for example) want to return all small
2040 structures in registers regardless of the structure's alignment.
2042 Deal with them explicitly by copying from the return registers
2043 into the target MEM locations. */
2044 int bytes = int_size_in_bytes (TREE_TYPE (exp));
2045 int n_regs = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
2047 enum machine_mode tmpmode;
2051 target = assign_stack_temp (BLKmode, bytes, 0);
2052 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
2053 preserve_temp_slots (target);
2056 /* We could probably emit more efficient code for machines
2057 which do not use strict alignment, but it doesn't seem
2058 worth the effort at the current time. */
2059 for (i = 0; i < n_regs; i++)
2061 rtx src = operand_subword_force (valreg, i, BLKmode);
2062 rtx dst = operand_subword (target, i, 1, BLKmode);
2063 int bitsize = MIN (TYPE_ALIGN (TREE_TYPE (exp)), BITS_PER_WORD);
2064 int bitpos, big_endian_correction = 0;
2066 /* Should never happen. */
2067 if (src == NULL || dst == NULL)
2070 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
2071 big_endian_correction
2072 = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
2075 bitpos < BITS_PER_WORD && bytes > 0;
2076 bitpos += bitsize, bytes -= bitsize / BITS_PER_UNIT)
2078 int xbitpos = bitpos + big_endian_correction;
2080 store_bit_field (dst, bitsize, xbitpos, word_mode,
2081 extract_bit_field (src, bitsize, bitpos, 1,
2082 NULL_RTX, word_mode,
2084 bitsize / BITS_PER_UNIT,
2086 bitsize / BITS_PER_UNIT, BITS_PER_WORD);
2091 target = copy_to_reg (valreg);
2093 #ifdef PROMOTE_FUNCTION_RETURN
2094 /* If we promoted this return value, make the proper SUBREG. TARGET
2095 might be const0_rtx here, so be careful. */
2096 if (GET_CODE (target) == REG
2097 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
2098 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
2100 tree type = TREE_TYPE (exp);
2101 int unsignedp = TREE_UNSIGNED (type);
2103 /* If we don't promote as expected, something is wrong. */
2104 if (GET_MODE (target)
2105 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
2108 target = gen_rtx (SUBREG, TYPE_MODE (type), target, 0);
2109 SUBREG_PROMOTED_VAR_P (target) = 1;
2110 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
2114 if (flag_short_temps)
2116 /* Perform all cleanups needed for the arguments of this call
2117 (i.e. destructors in C++). */
2118 expand_cleanups_to (old_cleanups);
2121 /* If size of args is variable or this was a constructor call for a stack
2122 argument, restore saved stack-pointer value. */
2124 if (old_stack_level)
2126 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
2127 pending_stack_adjust = old_pending_adj;
2128 #ifdef ACCUMULATE_OUTGOING_ARGS
2129 stack_arg_under_construction = old_stack_arg_under_construction;
2130 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2131 stack_usage_map = initial_stack_usage_map;
2134 #ifdef ACCUMULATE_OUTGOING_ARGS
2137 #ifdef REG_PARM_STACK_SPACE
2140 enum machine_mode save_mode = GET_MODE (save_area);
2142 = gen_rtx (MEM, save_mode,
2143 memory_address (save_mode,
2144 #ifdef ARGS_GROW_DOWNWARD
2145 plus_constant (argblock, - high_to_save)
2147 plus_constant (argblock, low_to_save)
2151 if (save_mode != BLKmode)
2152 emit_move_insn (stack_area, save_area);
2154 emit_block_move (stack_area, validize_mem (save_area),
2155 GEN_INT (high_to_save - low_to_save + 1),
2156 PARM_BOUNDARY / BITS_PER_UNIT);
2160 /* If we saved any argument areas, restore them. */
2161 for (i = 0; i < num_actuals; i++)
2162 if (args[i].save_area)
2164 enum machine_mode save_mode = GET_MODE (args[i].save_area);
2166 = gen_rtx (MEM, save_mode,
2167 memory_address (save_mode,
2168 XEXP (args[i].stack_slot, 0)));
2170 if (save_mode != BLKmode)
2171 emit_move_insn (stack_area, args[i].save_area);
2173 emit_block_move (stack_area, validize_mem (args[i].save_area),
2174 GEN_INT (args[i].size.constant),
2175 PARM_BOUNDARY / BITS_PER_UNIT);
2178 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2179 stack_usage_map = initial_stack_usage_map;
2183 /* If this was alloca, record the new stack level for nonlocal gotos.
2184 Check for the handler slots since we might not have a save area
2185 for non-local gotos. */
2187 if (may_be_alloca && nonlocal_goto_handler_slot != 0)
2188 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
2195 /* Output a library call to function FUN (a SYMBOL_REF rtx)
2196 (emitting the queue unless NO_QUEUE is nonzero),
2197 for a value of mode OUTMODE,
2198 with NARGS different arguments, passed as alternating rtx values
2199 and machine_modes to convert them to.
2200 The rtx values should have been passed through protect_from_queue already.
2202 NO_QUEUE will be true if and only if the library call is a `const' call
2203 which will be enclosed in REG_LIBCALL/REG_RETVAL notes; it is equivalent
2204 to the variable is_const in expand_call.
2206 NO_QUEUE must be true for const calls, because if it isn't, then
2207 any pending increment will be emitted between REG_LIBCALL/REG_RETVAL notes,
2208 and will be lost if the libcall sequence is optimized away.
2210 NO_QUEUE must be false for non-const calls, because if it isn't, the
2211 call insn will have its CONST_CALL_P bit set, and it will be incorrectly
2212 optimized. For instance, the instruction scheduler may incorrectly
2213 move memory references across the non-const call. */
2216 emit_library_call VPROTO((rtx orgfun, int no_queue, enum machine_mode outmode,
2222 enum machine_mode outmode;
2226 /* Total size in bytes of all the stack-parms scanned so far. */
2227 struct args_size args_size;
2228 /* Size of arguments before any adjustments (such as rounding). */
2229 struct args_size original_args_size;
2230 register int argnum;
2235 CUMULATIVE_ARGS args_so_far;
2236 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2237 struct args_size offset; struct args_size size; };
2239 int old_inhibit_defer_pop = inhibit_defer_pop;
2240 rtx call_fusage = 0;
2241 /* library calls are never indirect calls. */
2242 int current_call_is_indirect = 0;
2244 VA_START (p, nargs);
2247 orgfun = va_arg (p, rtx);
2248 no_queue = va_arg (p, int);
2249 outmode = va_arg (p, enum machine_mode);
2250 nargs = va_arg (p, int);
2255 /* Copy all the libcall-arguments out of the varargs data
2256 and into a vector ARGVEC.
2258 Compute how to pass each argument. We only support a very small subset
2259 of the full argument passing conventions to limit complexity here since
2260 library functions shouldn't have many args. */
2262 argvec = (struct arg *) alloca (nargs * sizeof (struct arg));
2264 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun);
2266 args_size.constant = 0;
2271 for (count = 0; count < nargs; count++)
2273 rtx val = va_arg (p, rtx);
2274 enum machine_mode mode = va_arg (p, enum machine_mode);
2276 /* We cannot convert the arg value to the mode the library wants here;
2277 must do it earlier where we know the signedness of the arg. */
2279 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2282 /* On some machines, there's no way to pass a float to a library fcn.
2283 Pass it as a double instead. */
2284 #ifdef LIBGCC_NEEDS_DOUBLE
2285 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2286 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
2289 /* There's no need to call protect_from_queue, because
2290 either emit_move_insn or emit_push_insn will do that. */
2292 /* Make sure it is a reasonable operand for a move or push insn. */
2293 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2294 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2295 val = force_operand (val, NULL_RTX);
2297 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2298 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2300 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2301 be viewed as just an efficiency improvement. */
2302 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2303 emit_move_insn (slot, val);
2304 val = force_operand (XEXP (slot, 0), NULL_RTX);
2309 argvec[count].value = val;
2310 argvec[count].mode = mode;
2312 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2313 if (argvec[count].reg && GET_CODE (argvec[count].reg) == EXPR_LIST)
2315 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2316 argvec[count].partial
2317 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2319 argvec[count].partial = 0;
2322 locate_and_pad_parm (mode, NULL_TREE,
2323 argvec[count].reg && argvec[count].partial == 0,
2324 NULL_TREE, &args_size, &argvec[count].offset,
2325 &argvec[count].size);
2327 if (argvec[count].size.var)
2330 #ifndef REG_PARM_STACK_SPACE
2331 if (argvec[count].partial)
2332 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2335 if (argvec[count].reg == 0 || argvec[count].partial != 0
2336 #ifdef REG_PARM_STACK_SPACE
2340 args_size.constant += argvec[count].size.constant;
2342 #ifdef ACCUMULATE_OUTGOING_ARGS
2343 /* If this arg is actually passed on the stack, it might be
2344 clobbering something we already put there (this library call might
2345 be inside the evaluation of an argument to a function whose call
2346 requires the stack). This will only occur when the library call
2347 has sufficient args to run out of argument registers. Abort in
2348 this case; if this ever occurs, code must be added to save and
2349 restore the arg slot. */
2351 if (argvec[count].reg == 0 || argvec[count].partial != 0)
2355 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree)0, 1);
2359 /* If this machine requires an external definition for library
2360 functions, write one out. */
2361 assemble_external_libcall (fun);
2363 original_args_size = args_size;
2364 #ifdef STACK_BOUNDARY
2365 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2366 / STACK_BYTES) * STACK_BYTES);
2369 #ifdef REG_PARM_STACK_SPACE
2370 args_size.constant = MAX (args_size.constant,
2371 REG_PARM_STACK_SPACE (NULL_TREE));
2372 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2373 args_size.constant -= REG_PARM_STACK_SPACE (NULL_TREE);
2377 if (args_size.constant > current_function_outgoing_args_size)
2378 current_function_outgoing_args_size = args_size.constant;
2380 #ifdef ACCUMULATE_OUTGOING_ARGS
2381 args_size.constant = 0;
2384 #ifndef PUSH_ROUNDING
2385 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2388 #ifdef PUSH_ARGS_REVERSED
2389 #ifdef STACK_BOUNDARY
2390 /* If we push args individually in reverse order, perform stack alignment
2391 before the first push (the last arg). */
2393 anti_adjust_stack (GEN_INT (args_size.constant
2394 - original_args_size.constant));
2398 #ifdef PUSH_ARGS_REVERSED
2406 /* Push the args that need to be pushed. */
2408 for (count = 0; count < nargs; count++, argnum += inc)
2410 register enum machine_mode mode = argvec[argnum].mode;
2411 register rtx val = argvec[argnum].value;
2412 rtx reg = argvec[argnum].reg;
2413 int partial = argvec[argnum].partial;
2415 if (! (reg != 0 && partial == 0))
2416 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2417 argblock, GEN_INT (argvec[count].offset.constant));
2421 #ifndef PUSH_ARGS_REVERSED
2422 #ifdef STACK_BOUNDARY
2423 /* If we pushed args in forward order, perform stack alignment
2424 after pushing the last arg. */
2426 anti_adjust_stack (GEN_INT (args_size.constant
2427 - original_args_size.constant));
2431 #ifdef PUSH_ARGS_REVERSED
2437 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
2439 /* Now load any reg parms into their regs. */
2441 for (count = 0; count < nargs; count++, argnum += inc)
2443 register enum machine_mode mode = argvec[argnum].mode;
2444 register rtx val = argvec[argnum].value;
2445 rtx reg = argvec[argnum].reg;
2446 int partial = argvec[argnum].partial;
2448 if (reg != 0 && partial == 0)
2449 emit_move_insn (reg, val);
2453 /* For version 1.37, try deleting this entirely. */
2457 /* Any regs containing parms remain in use through the call. */
2458 for (count = 0; count < nargs; count++)
2459 if (argvec[count].reg != 0)
2460 use_reg (&call_fusage, argvec[count].reg);
2462 /* Don't allow popping to be deferred, since then
2463 cse'ing of library calls could delete a call and leave the pop. */
2466 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2467 will set inhibit_defer_pop to that value. */
2470 get_identifier (XSTR (orgfun, 0)),
2471 get_identifier (XSTR (orgfun, 0)), args_size.constant, 0,
2472 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2473 outmode != VOIDmode ? hard_libcall_value (outmode) : NULL_RTX,
2474 old_inhibit_defer_pop + 1, call_fusage, no_queue);
2478 /* Now restore inhibit_defer_pop to its actual original value. */
2482 /* Like emit_library_call except that an extra argument, VALUE,
2483 comes second and says where to store the result.
2484 (If VALUE is zero, this function chooses a convenient way
2485 to return the value.
2487 This function returns an rtx for where the value is to be found.
2488 If VALUE is nonzero, VALUE is returned. */
2491 emit_library_call_value VPROTO((rtx orgfun, rtx value, int no_queue,
2492 enum machine_mode outmode, int nargs, ...))
2498 enum machine_mode outmode;
2502 /* Total size in bytes of all the stack-parms scanned so far. */
2503 struct args_size args_size;
2504 /* Size of arguments before any adjustments (such as rounding). */
2505 struct args_size original_args_size;
2506 register int argnum;
2511 CUMULATIVE_ARGS args_so_far;
2512 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2513 struct args_size offset; struct args_size size; };
2515 int old_inhibit_defer_pop = inhibit_defer_pop;
2516 rtx call_fusage = 0;
2518 int pcc_struct_value = 0;
2519 int struct_value_size = 0;
2520 /* library calls are never indirect calls. */
2521 int current_call_is_indirect = 0;
2524 VA_START (p, nargs);
2527 orgfun = va_arg (p, rtx);
2528 value = va_arg (p, rtx);
2529 no_queue = va_arg (p, int);
2530 outmode = va_arg (p, enum machine_mode);
2531 nargs = va_arg (p, int);
2534 is_const = no_queue;
2537 /* If this kind of value comes back in memory,
2538 decide where in memory it should come back. */
2539 if (aggregate_value_p (type_for_mode (outmode, 0)))
2541 #ifdef PCC_STATIC_STRUCT_RETURN
2543 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
2545 mem_value = gen_rtx (MEM, outmode, pointer_reg);
2546 pcc_struct_value = 1;
2548 value = gen_reg_rtx (outmode);
2549 #else /* not PCC_STATIC_STRUCT_RETURN */
2550 struct_value_size = GET_MODE_SIZE (outmode);
2551 if (value != 0 && GET_CODE (value) == MEM)
2554 mem_value = assign_stack_temp (outmode, GET_MODE_SIZE (outmode), 0);
2557 /* This call returns a big structure. */
2561 /* ??? Unfinished: must pass the memory address as an argument. */
2563 /* Copy all the libcall-arguments out of the varargs data
2564 and into a vector ARGVEC.
2566 Compute how to pass each argument. We only support a very small subset
2567 of the full argument passing conventions to limit complexity here since
2568 library functions shouldn't have many args. */
2570 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
2572 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun);
2574 args_size.constant = 0;
2581 /* If there's a structure value address to be passed,
2582 either pass it in the special place, or pass it as an extra argument. */
2583 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
2585 rtx addr = XEXP (mem_value, 0);
2588 /* Make sure it is a reasonable operand for a move or push insn. */
2589 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
2590 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
2591 addr = force_operand (addr, NULL_RTX);
2593 argvec[count].value = addr;
2594 argvec[count].mode = Pmode;
2595 argvec[count].partial = 0;
2597 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
2598 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2599 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
2603 locate_and_pad_parm (Pmode, NULL_TREE,
2604 argvec[count].reg && argvec[count].partial == 0,
2605 NULL_TREE, &args_size, &argvec[count].offset,
2606 &argvec[count].size);
2609 if (argvec[count].reg == 0 || argvec[count].partial != 0
2610 #ifdef REG_PARM_STACK_SPACE
2614 args_size.constant += argvec[count].size.constant;
2616 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree)0, 1);
2621 for (; count < nargs; count++)
2623 rtx val = va_arg (p, rtx);
2624 enum machine_mode mode = va_arg (p, enum machine_mode);
2626 /* We cannot convert the arg value to the mode the library wants here;
2627 must do it earlier where we know the signedness of the arg. */
2629 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2632 /* On some machines, there's no way to pass a float to a library fcn.
2633 Pass it as a double instead. */
2634 #ifdef LIBGCC_NEEDS_DOUBLE
2635 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2636 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
2639 /* There's no need to call protect_from_queue, because
2640 either emit_move_insn or emit_push_insn will do that. */
2642 /* Make sure it is a reasonable operand for a move or push insn. */
2643 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2644 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2645 val = force_operand (val, NULL_RTX);
2647 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2648 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2650 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2651 be viewed as just an efficiency improvement. */
2652 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2653 emit_move_insn (slot, val);
2654 val = XEXP (slot, 0);
2659 argvec[count].value = val;
2660 argvec[count].mode = mode;
2662 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2663 if (argvec[count].reg && GET_CODE (argvec[count].reg) == EXPR_LIST)
2665 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2666 argvec[count].partial
2667 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2669 argvec[count].partial = 0;
2672 locate_and_pad_parm (mode, NULL_TREE,
2673 argvec[count].reg && argvec[count].partial == 0,
2674 NULL_TREE, &args_size, &argvec[count].offset,
2675 &argvec[count].size);
2677 if (argvec[count].size.var)
2680 #ifndef REG_PARM_STACK_SPACE
2681 if (argvec[count].partial)
2682 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2685 if (argvec[count].reg == 0 || argvec[count].partial != 0
2686 #ifdef REG_PARM_STACK_SPACE
2690 args_size.constant += argvec[count].size.constant;
2692 #ifdef ACCUMULATE_OUTGOING_ARGS
2693 /* If this arg is actually passed on the stack, it might be
2694 clobbering something we already put there (this library call might
2695 be inside the evaluation of an argument to a function whose call
2696 requires the stack). This will only occur when the library call
2697 has sufficient args to run out of argument registers. Abort in
2698 this case; if this ever occurs, code must be added to save and
2699 restore the arg slot. */
2701 if (argvec[count].reg == 0 || argvec[count].partial != 0)
2705 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree)0, 1);
2709 /* If this machine requires an external definition for library
2710 functions, write one out. */
2711 assemble_external_libcall (fun);
2713 original_args_size = args_size;
2714 #ifdef STACK_BOUNDARY
2715 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2716 / STACK_BYTES) * STACK_BYTES);
2719 #ifdef REG_PARM_STACK_SPACE
2720 args_size.constant = MAX (args_size.constant,
2721 REG_PARM_STACK_SPACE (NULL_TREE));
2722 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2723 args_size.constant -= REG_PARM_STACK_SPACE (NULL_TREE);
2727 if (args_size.constant > current_function_outgoing_args_size)
2728 current_function_outgoing_args_size = args_size.constant;
2730 #ifdef ACCUMULATE_OUTGOING_ARGS
2731 args_size.constant = 0;
2734 #ifndef PUSH_ROUNDING
2735 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2738 #ifdef PUSH_ARGS_REVERSED
2739 #ifdef STACK_BOUNDARY
2740 /* If we push args individually in reverse order, perform stack alignment
2741 before the first push (the last arg). */
2743 anti_adjust_stack (GEN_INT (args_size.constant
2744 - original_args_size.constant));
2748 #ifdef PUSH_ARGS_REVERSED
2756 /* Push the args that need to be pushed. */
2758 for (count = 0; count < nargs; count++, argnum += inc)
2760 register enum machine_mode mode = argvec[argnum].mode;
2761 register rtx val = argvec[argnum].value;
2762 rtx reg = argvec[argnum].reg;
2763 int partial = argvec[argnum].partial;
2765 if (! (reg != 0 && partial == 0))
2766 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2767 argblock, GEN_INT (argvec[count].offset.constant));
2771 #ifndef PUSH_ARGS_REVERSED
2772 #ifdef STACK_BOUNDARY
2773 /* If we pushed args in forward order, perform stack alignment
2774 after pushing the last arg. */
2776 anti_adjust_stack (GEN_INT (args_size.constant
2777 - original_args_size.constant));
2781 #ifdef PUSH_ARGS_REVERSED
2787 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
2789 /* Now load any reg parms into their regs. */
2791 for (count = 0; count < nargs; count++, argnum += inc)
2793 register enum machine_mode mode = argvec[argnum].mode;
2794 register rtx val = argvec[argnum].value;
2795 rtx reg = argvec[argnum].reg;
2796 int partial = argvec[argnum].partial;
2798 if (reg != 0 && partial == 0)
2799 emit_move_insn (reg, val);
2804 /* For version 1.37, try deleting this entirely. */
2809 /* Any regs containing parms remain in use through the call. */
2810 for (count = 0; count < nargs; count++)
2811 if (argvec[count].reg != 0)
2812 use_reg (&call_fusage, argvec[count].reg);
2814 /* Pass the function the address in which to return a structure value. */
2815 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
2817 emit_move_insn (struct_value_rtx,
2819 force_operand (XEXP (mem_value, 0),
2821 if (GET_CODE (struct_value_rtx) == REG)
2822 use_reg (&call_fusage, struct_value_rtx);
2825 /* Don't allow popping to be deferred, since then
2826 cse'ing of library calls could delete a call and leave the pop. */
2829 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2830 will set inhibit_defer_pop to that value. */
2833 get_identifier (XSTR (orgfun, 0)),
2834 get_identifier (XSTR (orgfun, 0)), args_size.constant,
2836 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2837 (outmode != VOIDmode && mem_value == 0
2838 ? hard_libcall_value (outmode) : NULL_RTX),
2839 old_inhibit_defer_pop + 1, call_fusage, is_const);
2841 /* Now restore inhibit_defer_pop to its actual original value. */
2846 /* Copy the value to the right place. */
2847 if (outmode != VOIDmode)
2853 if (value != mem_value)
2854 emit_move_insn (value, mem_value);
2856 else if (value != 0)
2857 emit_move_insn (value, hard_libcall_value (outmode));
2859 value = hard_libcall_value (outmode);
2866 /* Return an rtx which represents a suitable home on the stack
2867 given TYPE, the type of the argument looking for a home.
2868 This is called only for BLKmode arguments.
2870 SIZE is the size needed for this target.
2871 ARGS_ADDR is the address of the bottom of the argument block for this call.
2872 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
2873 if this machine uses push insns. */
2876 target_for_arg (type, size, args_addr, offset)
2880 struct args_size offset;
2883 rtx offset_rtx = ARGS_SIZE_RTX (offset);
2885 /* We do not call memory_address if possible,
2886 because we want to address as close to the stack
2887 as possible. For non-variable sized arguments,
2888 this will be stack-pointer relative addressing. */
2889 if (GET_CODE (offset_rtx) == CONST_INT)
2890 target = plus_constant (args_addr, INTVAL (offset_rtx));
2893 /* I have no idea how to guarantee that this
2894 will work in the presence of register parameters. */
2895 target = gen_rtx (PLUS, Pmode, args_addr, offset_rtx);
2896 target = memory_address (QImode, target);
2899 return gen_rtx (MEM, BLKmode, target);
2903 /* Store a single argument for a function call
2904 into the register or memory area where it must be passed.
2905 *ARG describes the argument value and where to pass it.
2907 ARGBLOCK is the address of the stack-block for all the arguments,
2908 or 0 on a machine where arguments are pushed individually.
2910 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
2911 so must be careful about how the stack is used.
2913 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
2914 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
2915 that we need not worry about saving and restoring the stack.
2917 FNDECL is the declaration of the function we are calling. */
2920 store_one_arg (arg, argblock, may_be_alloca, variable_size, fndecl,
2921 reg_parm_stack_space)
2922 struct arg_data *arg;
2927 int reg_parm_stack_space;
2929 register tree pval = arg->tree_value;
2933 int i, lower_bound, upper_bound;
2935 if (TREE_CODE (pval) == ERROR_MARK)
2938 /* Push a new temporary level for any temporaries we make for
2942 #ifdef ACCUMULATE_OUTGOING_ARGS
2943 /* If this is being stored into a pre-allocated, fixed-size, stack area,
2944 save any previous data at that location. */
2945 if (argblock && ! variable_size && arg->stack)
2947 #ifdef ARGS_GROW_DOWNWARD
2948 /* stack_slot is negative, but we want to index stack_usage_map */
2949 /* with positive values. */
2950 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
2951 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
2955 lower_bound = upper_bound - arg->size.constant;
2957 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
2958 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
2962 upper_bound = lower_bound + arg->size.constant;
2965 for (i = lower_bound; i < upper_bound; i++)
2966 if (stack_usage_map[i]
2967 #ifdef REG_PARM_STACK_SPACE
2968 /* Don't store things in the fixed argument area at this point;
2969 it has already been saved. */
2970 && i > reg_parm_stack_space
2975 if (i != upper_bound)
2977 /* We need to make a save area. See what mode we can make it. */
2978 enum machine_mode save_mode
2979 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
2981 = gen_rtx (MEM, save_mode,
2982 memory_address (save_mode, XEXP (arg->stack_slot, 0)));
2984 if (save_mode == BLKmode)
2986 arg->save_area = assign_stack_temp (BLKmode,
2987 arg->size.constant, 0);
2988 MEM_IN_STRUCT_P (arg->save_area)
2989 = AGGREGATE_TYPE_P (TREE_TYPE (arg->tree_value));
2990 preserve_temp_slots (arg->save_area);
2991 emit_block_move (validize_mem (arg->save_area), stack_area,
2992 GEN_INT (arg->size.constant),
2993 PARM_BOUNDARY / BITS_PER_UNIT);
2997 arg->save_area = gen_reg_rtx (save_mode);
2998 emit_move_insn (arg->save_area, stack_area);
3004 /* If this isn't going to be placed on both the stack and in registers,
3005 set up the register and number of words. */
3006 if (! arg->pass_on_stack)
3007 reg = arg->reg, partial = arg->partial;
3009 if (reg != 0 && partial == 0)
3010 /* Being passed entirely in a register. We shouldn't be called in
3014 #ifdef STRICT_ALIGNMENT
3015 /* If this arg needs special alignment, don't load the registers
3017 if (arg->n_aligned_regs != 0)
3021 /* If this is being partially passed in a register, but multiple locations
3022 are specified, we assume that the one partially used is the one that is
3024 if (reg && GET_CODE (reg) == EXPR_LIST)
3025 reg = XEXP (reg, 0);
3027 /* If this is being passed partially in a register, we can't evaluate
3028 it directly into its stack slot. Otherwise, we can. */
3029 if (arg->value == 0)
3031 #ifdef ACCUMULATE_OUTGOING_ARGS
3032 /* stack_arg_under_construction is nonzero if a function argument is
3033 being evaluated directly into the outgoing argument list and
3034 expand_call must take special action to preserve the argument list
3035 if it is called recursively.
3037 For scalar function arguments stack_usage_map is sufficient to
3038 determine which stack slots must be saved and restored. Scalar
3039 arguments in general have pass_on_stack == 0.
3041 If this argument is initialized by a function which takes the
3042 address of the argument (a C++ constructor or a C function
3043 returning a BLKmode structure), then stack_usage_map is
3044 insufficient and expand_call must push the stack around the
3045 function call. Such arguments have pass_on_stack == 1.
3047 Note that it is always safe to set stack_arg_under_construction,
3048 but this generates suboptimal code if set when not needed. */
3050 if (arg->pass_on_stack)
3051 stack_arg_under_construction++;
3053 arg->value = expand_expr (pval,
3055 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
3056 ? NULL_RTX : arg->stack,
3059 /* If we are promoting object (or for any other reason) the mode
3060 doesn't agree, convert the mode. */
3062 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
3063 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
3064 arg->value, arg->unsignedp);
3066 #ifdef ACCUMULATE_OUTGOING_ARGS
3067 if (arg->pass_on_stack)
3068 stack_arg_under_construction--;
3072 /* Don't allow anything left on stack from computation
3073 of argument to alloca. */
3075 do_pending_stack_adjust ();
3077 if (arg->value == arg->stack)
3078 /* If the value is already in the stack slot, we are done. */
3080 else if (arg->mode != BLKmode)
3084 /* Argument is a scalar, not entirely passed in registers.
3085 (If part is passed in registers, arg->partial says how much
3086 and emit_push_insn will take care of putting it there.)
3088 Push it, and if its size is less than the
3089 amount of space allocated to it,
3090 also bump stack pointer by the additional space.
3091 Note that in C the default argument promotions
3092 will prevent such mismatches. */
3094 size = GET_MODE_SIZE (arg->mode);
3095 /* Compute how much space the push instruction will push.
3096 On many machines, pushing a byte will advance the stack
3097 pointer by a halfword. */
3098 #ifdef PUSH_ROUNDING
3099 size = PUSH_ROUNDING (size);
3103 /* Compute how much space the argument should get:
3104 round up to a multiple of the alignment for arguments. */
3105 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
3106 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
3107 / (PARM_BOUNDARY / BITS_PER_UNIT))
3108 * (PARM_BOUNDARY / BITS_PER_UNIT));
3110 /* This isn't already where we want it on the stack, so put it there.
3111 This can either be done with push or copy insns. */
3112 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
3113 0, partial, reg, used - size,
3114 argblock, ARGS_SIZE_RTX (arg->offset));
3118 /* BLKmode, at least partly to be pushed. */
3120 register int excess;
3123 /* Pushing a nonscalar.
3124 If part is passed in registers, PARTIAL says how much
3125 and emit_push_insn will take care of putting it there. */
3127 /* Round its size up to a multiple
3128 of the allocation unit for arguments. */
3130 if (arg->size.var != 0)
3133 size_rtx = ARGS_SIZE_RTX (arg->size);
3137 /* PUSH_ROUNDING has no effect on us, because
3138 emit_push_insn for BLKmode is careful to avoid it. */
3139 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
3140 + partial * UNITS_PER_WORD);
3141 size_rtx = expr_size (pval);
3144 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
3145 TYPE_ALIGN (TREE_TYPE (pval)) / BITS_PER_UNIT, partial,
3146 reg, excess, argblock, ARGS_SIZE_RTX (arg->offset));
3150 /* Unless this is a partially-in-register argument, the argument is now
3153 ??? Note that this can change arg->value from arg->stack to
3154 arg->stack_slot and it matters when they are not the same.
3155 It isn't totally clear that this is correct in all cases. */
3157 arg->value = arg->stack_slot;
3159 /* Once we have pushed something, pops can't safely
3160 be deferred during the rest of the arguments. */
3163 /* ANSI doesn't require a sequence point here,
3164 but PCC has one, so this will avoid some problems. */
3167 /* Free any temporary slots made in processing this argument. Show
3168 that we might have taken the address of something and pushed that
3170 preserve_temp_slots (NULL_RTX);
3174 #ifdef ACCUMULATE_OUTGOING_ARGS
3175 /* Now mark the segment we just used. */
3176 if (argblock && ! variable_size && arg->stack)
3177 for (i = lower_bound; i < upper_bound; i++)
3178 stack_usage_map[i] = 1;