1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 92, 93, 94, 95, 1996 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
31 #include "insn-flags.h"
33 /* Decide whether a function's arguments should be processed
34 from first to last or from last to first.
36 They should if the stack and args grow in opposite directions, but
37 only if we have push insns. */
41 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
42 #define PUSH_ARGS_REVERSED /* If it's last to first */
47 /* Like STACK_BOUNDARY but in units of bytes, not bits. */
48 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
50 /* Data structure and subroutines used within expand_call. */
54 /* Tree node for this argument. */
56 /* Mode for value; TYPE_MODE unless promoted. */
57 enum machine_mode mode;
58 /* Current RTL value for argument, or 0 if it isn't precomputed. */
60 /* Initially-compute RTL value for argument; only for const functions. */
62 /* Register to pass this argument in, 0 if passed on stack, or an
63 EXPR_LIST if the arg is to be copied into multiple different
66 /* If REG was promoted from the actual mode of the argument expression,
67 indicates whether the promotion is sign- or zero-extended. */
69 /* Number of registers to use. 0 means put the whole arg in registers.
70 Also 0 if not passed in registers. */
72 /* Non-zero if argument must be passed on stack.
73 Note that some arguments may be passed on the stack
74 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
75 pass_on_stack identifies arguments that *cannot* go in registers. */
77 /* Offset of this argument from beginning of stack-args. */
78 struct args_size offset;
79 /* Similar, but offset to the start of the stack slot. Different from
80 OFFSET if this arg pads downward. */
81 struct args_size slot_offset;
82 /* Size of this argument on the stack, rounded up for any padding it gets,
83 parts of the argument passed in registers do not count.
84 If REG_PARM_STACK_SPACE is defined, then register parms
85 are counted here as well. */
86 struct args_size size;
87 /* Location on the stack at which parameter should be stored. The store
88 has already been done if STACK == VALUE. */
90 /* Location on the stack of the start of this argument slot. This can
91 differ from STACK if this arg pads downward. This location is known
92 to be aligned to FUNCTION_ARG_BOUNDARY. */
94 #ifdef ACCUMULATE_OUTGOING_ARGS
95 /* Place that this stack area has been saved, if needed. */
98 /* 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. */
106 #ifdef ACCUMULATE_OUTGOING_ARGS
107 /* A vector of one char per byte of stack space. A byte if non-zero if
108 the corresponding stack location has been used.
109 This vector is used to prevent a function call within an argument from
110 clobbering any stack already set up. */
111 static char *stack_usage_map;
113 /* Size of STACK_USAGE_MAP. */
114 static int highest_outgoing_arg_in_use;
116 /* stack_arg_under_construction is nonzero when an argument may be
117 initialized with a constructor call (including a C function that
118 returns a BLKmode struct) and expand_call must take special action
119 to make sure the object being constructed does not overlap the
120 argument list for the constructor call. */
121 int stack_arg_under_construction;
124 static int calls_function PROTO((tree, int));
125 static int calls_function_1 PROTO((tree, int));
126 static void emit_call_1 PROTO((rtx, tree, tree, int, int, rtx, rtx,
128 static void store_one_arg PROTO ((struct arg_data *, rtx, int, int,
131 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
134 If WHICH is 0, return 1 if EXP contains a call to any function.
135 Actually, we only need return 1 if evaluating EXP would require pushing
136 arguments on the stack, but that is too difficult to compute, so we just
137 assume any function call might require the stack. */
139 static tree calls_function_save_exprs;
142 calls_function (exp, which)
147 calls_function_save_exprs = 0;
148 val = calls_function_1 (exp, which);
149 calls_function_save_exprs = 0;
154 calls_function_1 (exp, which)
159 enum tree_code code = TREE_CODE (exp);
160 int type = TREE_CODE_CLASS (code);
161 int length = tree_code_length[(int) code];
163 /* If this code is language-specific, we don't know what it will do. */
164 if ((int) code >= NUM_TREE_CODES)
167 /* Only expressions and references can contain calls. */
168 if (type != 'e' && type != '<' && type != '1' && type != '2' && type != 'r'
177 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
178 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
181 tree fndecl = TREE_OPERAND (TREE_OPERAND (exp, 0), 0);
183 if ((DECL_BUILT_IN (fndecl)
184 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_ALLOCA)
185 || (DECL_SAVED_INSNS (fndecl)
186 && (FUNCTION_FLAGS (DECL_SAVED_INSNS (fndecl))
187 & FUNCTION_FLAGS_CALLS_ALLOCA)))
191 /* Third operand is RTL. */
196 if (SAVE_EXPR_RTL (exp) != 0)
198 if (value_member (exp, calls_function_save_exprs))
200 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
201 calls_function_save_exprs);
202 return (TREE_OPERAND (exp, 0) != 0
203 && calls_function_1 (TREE_OPERAND (exp, 0), which));
209 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
210 if (DECL_INITIAL (local) != 0
211 && calls_function_1 (DECL_INITIAL (local), which))
215 register tree subblock;
217 for (subblock = BLOCK_SUBBLOCKS (exp);
219 subblock = TREE_CHAIN (subblock))
220 if (calls_function_1 (subblock, which))
225 case METHOD_CALL_EXPR:
229 case WITH_CLEANUP_EXPR:
237 for (i = 0; i < length; i++)
238 if (TREE_OPERAND (exp, i) != 0
239 && calls_function_1 (TREE_OPERAND (exp, i), which))
245 /* Force FUNEXP into a form suitable for the address of a CALL,
246 and return that as an rtx. Also load the static chain register
247 if FNDECL is a nested function.
249 CALL_FUSAGE points to a variable holding the prospective
250 CALL_INSN_FUNCTION_USAGE information. */
253 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen)
259 rtx static_chain_value = 0;
261 funexp = protect_from_queue (funexp, 0);
264 /* Get possible static chain value for nested function in C. */
265 static_chain_value = lookup_static_chain (fndecl);
267 /* Make a valid memory address and copy constants thru pseudo-regs,
268 but not for a constant address if -fno-function-cse. */
269 if (GET_CODE (funexp) != SYMBOL_REF)
271 #ifdef SMALL_REGISTER_CLASSES
272 /* If we are using registers for parameters, force the
273 function address into a register now. */
274 reg_parm_seen ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
277 memory_address (FUNCTION_MODE, funexp);
280 #ifndef NO_FUNCTION_CSE
281 if (optimize && ! flag_no_function_cse)
282 #ifdef NO_RECURSIVE_FUNCTION_CSE
283 if (fndecl != current_function_decl)
285 funexp = force_reg (Pmode, funexp);
289 if (static_chain_value != 0)
291 emit_move_insn (static_chain_rtx, static_chain_value);
293 if (GET_CODE (static_chain_rtx) == REG)
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
622 warning_with_decl (fndecl, "can't inline call to `%s'");
623 warning ("called from here");
625 mark_addressable (fndecl);
628 if (TREE_READONLY (fndecl) && ! TREE_THIS_VOLATILE (fndecl)
629 && TYPE_MODE (TREE_TYPE (exp)) != VOIDmode)
632 if (TREE_THIS_VOLATILE (fndecl))
637 /* If we don't have specific function to call, see if we have a
638 constant or `noreturn' function from the type. */
641 is_const = TREE_READONLY (TREE_TYPE (TREE_TYPE (p)));
642 is_volatile = TREE_THIS_VOLATILE (TREE_TYPE (TREE_TYPE (p)));
645 #ifdef REG_PARM_STACK_SPACE
646 #ifdef MAYBE_REG_PARM_STACK_SPACE
647 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
649 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
653 /* Warn if this value is an aggregate type,
654 regardless of which calling convention we are using for it. */
655 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
656 warning ("function call has aggregate value");
658 /* Set up a place to return a structure. */
660 /* Cater to broken compilers. */
661 if (aggregate_value_p (exp))
663 /* This call returns a big structure. */
666 #ifdef PCC_STATIC_STRUCT_RETURN
668 pcc_struct_value = 1;
669 /* Easier than making that case work right. */
672 /* In case this is a static function, note that it has been
674 if (! TREE_ADDRESSABLE (fndecl))
675 mark_addressable (fndecl);
679 #else /* not PCC_STATIC_STRUCT_RETURN */
681 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
683 if (target && GET_CODE (target) == MEM)
684 structure_value_addr = XEXP (target, 0);
687 /* Assign a temporary on the stack to hold the value. */
689 /* For variable-sized objects, we must be called with a target
690 specified. If we were to allocate space on the stack here,
691 we would have no way of knowing when to free it. */
693 if (struct_value_size < 0)
697 = XEXP (assign_stack_temp (BLKmode, struct_value_size, 1), 0);
698 MEM_IN_STRUCT_P (structure_value_addr)
699 = AGGREGATE_TYPE_P (TREE_TYPE (exp));
703 #endif /* not PCC_STATIC_STRUCT_RETURN */
706 /* If called function is inline, try to integrate it. */
711 rtx before_call = get_last_insn ();
713 temp = expand_inline_function (fndecl, actparms, target,
714 ignore, TREE_TYPE (exp),
715 structure_value_addr);
717 /* If inlining succeeded, return. */
718 if ((HOST_WIDE_INT) temp != -1)
720 if (flag_short_temps)
722 /* Perform all cleanups needed for the arguments of this
723 call (i.e. destructors in C++). It is ok if these
724 destructors clobber RETURN_VALUE_REG, because the
725 only time we care about this is when TARGET is that
726 register. But in C++, we take care to never return
727 that register directly. */
728 expand_cleanups_to (old_cleanups);
731 #ifdef ACCUMULATE_OUTGOING_ARGS
732 /* If the outgoing argument list must be preserved, push
733 the stack before executing the inlined function if it
736 for (i = reg_parm_stack_space - 1; i >= 0; i--)
737 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
740 if (stack_arg_under_construction || i >= 0)
742 rtx insn = NEXT_INSN (before_call), seq;
744 /* Look for a call in the inline function code.
745 If OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl)) is
746 nonzero then there is a call and it is not necessary
747 to scan the insns. */
749 if (OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl)) == 0)
750 for (; insn; insn = NEXT_INSN (insn))
751 if (GET_CODE (insn) == CALL_INSN)
756 /* Reserve enough stack space so that the largest
757 argument list of any function call in the inline
758 function does not overlap the argument list being
759 evaluated. This is usually an overestimate because
760 allocate_dynamic_stack_space reserves space for an
761 outgoing argument list in addition to the requested
762 space, but there is no way to ask for stack space such
763 that an argument list of a certain length can be
764 safely constructed. */
766 int adjust = OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl));
767 #ifdef REG_PARM_STACK_SPACE
768 /* Add the stack space reserved for register arguments
769 in the inline function. What is really needed is the
770 largest value of reg_parm_stack_space in the inline
771 function, but that is not available. Using the current
772 value of reg_parm_stack_space is wrong, but gives
773 correct results on all supported machines. */
774 adjust += reg_parm_stack_space;
777 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
778 allocate_dynamic_stack_space (GEN_INT (adjust),
779 NULL_RTX, BITS_PER_UNIT);
782 emit_insns_before (seq, NEXT_INSN (before_call));
783 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
788 /* If the result is equivalent to TARGET, return TARGET to simplify
789 checks in store_expr. They can be equivalent but not equal in the
790 case of a function that returns BLKmode. */
791 if (temp != target && rtx_equal_p (temp, target))
796 /* If inlining failed, mark FNDECL as needing to be compiled
797 separately after all. If function was declared inline,
799 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
800 && optimize > 0 && ! TREE_ADDRESSABLE (fndecl))
802 warning_with_decl (fndecl, "inlining failed in call to `%s'");
803 warning ("called from here");
805 mark_addressable (fndecl);
808 /* When calling a const function, we must pop the stack args right away,
809 so that the pop is deleted or moved with the call. */
813 function_call_count++;
815 if (fndecl && DECL_NAME (fndecl))
816 name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
818 /* On some machines (such as the PA) indirect calls have a different
819 calling convention than normal calls. FUNCTION_ARG in the target
820 description can look at current_call_is_indirect to determine which
821 calling convention to use. */
822 current_call_is_indirect = (fndecl == 0);
824 = TREE_CODE (TREE_OPERAND (exp, 0)) == NON_LVALUE_EXPR ? 1 : 0;
828 /* Unless it's a call to a specific function that isn't alloca,
829 if it has one argument, we must assume it might be alloca. */
832 (!(fndecl != 0 && strcmp (name, "alloca"))
834 && TREE_CHAIN (actparms) == 0);
836 /* We assume that alloca will always be called by name. It
837 makes no sense to pass it as a pointer-to-function to
838 anything that does not understand its behavior. */
840 (name && ((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
842 && ! strcmp (name, "alloca"))
843 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
845 && ! strcmp (name, "__builtin_alloca"))));
848 /* See if this is a call to a function that can return more than once
849 or a call to longjmp. */
854 if (name != 0 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 15)
858 /* Disregard prefix _, __ or __x. */
861 if (name[1] == '_' && name[2] == 'x')
863 else if (name[1] == '_')
873 && (! strcmp (tname, "setjmp")
874 || ! strcmp (tname, "setjmp_syscall")))
876 && ! strcmp (tname, "sigsetjmp"))
878 && ! strcmp (tname, "savectx")));
880 && ! strcmp (tname, "siglongjmp"))
883 else if ((tname[0] == 'q' && tname[1] == 's'
884 && ! strcmp (tname, "qsetjmp"))
885 || (tname[0] == 'v' && tname[1] == 'f'
886 && ! strcmp (tname, "vfork")))
889 else if (tname[0] == 'l' && tname[1] == 'o'
890 && ! strcmp (tname, "longjmp"))
895 current_function_calls_alloca = 1;
897 /* Don't let pending stack adjusts add up to too much.
898 Also, do all pending adjustments now
899 if there is any chance this might be a call to alloca. */
901 if (pending_stack_adjust >= 32
902 || (pending_stack_adjust > 0 && may_be_alloca))
903 do_pending_stack_adjust ();
905 /* Operand 0 is a pointer-to-function; get the type of the function. */
906 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
907 if (TREE_CODE (funtype) != POINTER_TYPE)
909 funtype = TREE_TYPE (funtype);
911 /* Push the temporary stack slot level so that we can free any temporaries
915 /* Start updating where the next arg would go. */
916 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX);
918 /* If struct_value_rtx is 0, it means pass the address
919 as if it were an extra parameter. */
920 if (structure_value_addr && struct_value_rtx == 0)
922 /* If structure_value_addr is a REG other than
923 virtual_outgoing_args_rtx, we can use always use it. If it
924 is not a REG, we must always copy it into a register.
925 If it is virtual_outgoing_args_rtx, we must copy it to another
926 register in some cases. */
927 rtx temp = (GET_CODE (structure_value_addr) != REG
928 #ifdef ACCUMULATE_OUTGOING_ARGS
929 || (stack_arg_under_construction
930 && structure_value_addr == virtual_outgoing_args_rtx)
932 ? copy_addr_to_reg (structure_value_addr)
933 : structure_value_addr);
936 = tree_cons (error_mark_node,
937 make_tree (build_pointer_type (TREE_TYPE (funtype)),
940 structure_value_addr_parm = 1;
943 /* Count the arguments and set NUM_ACTUALS. */
944 for (p = actparms, i = 0; p; p = TREE_CHAIN (p)) i++;
947 /* Compute number of named args.
948 Normally, don't include the last named arg if anonymous args follow.
949 We do include the last named arg if STRICT_ARGUMENT_NAMING is defined.
950 (If no anonymous args follow, the result of list_length is actually
951 one too large. This is harmless.)
953 If SETUP_INCOMING_VARARGS is defined and STRICT_ARGUMENT_NAMING is not,
954 this machine will be able to place unnamed args that were passed in
955 registers into the stack. So treat all args as named. This allows the
956 insns emitting for a specific argument list to be independent of the
957 function declaration.
959 If SETUP_INCOMING_VARARGS is not defined, we do not have any reliable
960 way to pass unnamed args in registers, so we must force them into
962 #if !defined(SETUP_INCOMING_VARARGS) || defined(STRICT_ARGUMENT_NAMING)
963 if (TYPE_ARG_TYPES (funtype) != 0)
965 = (list_length (TYPE_ARG_TYPES (funtype))
966 #ifndef STRICT_ARGUMENT_NAMING
967 /* Don't include the last named arg. */
970 /* Count the struct value address, if it is passed as a parm. */
971 + structure_value_addr_parm);
974 /* If we know nothing, treat all args as named. */
975 n_named_args = num_actuals;
977 /* Make a vector to hold all the information about each arg. */
978 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
979 bzero ((char *) args, num_actuals * sizeof (struct arg_data));
981 args_size.constant = 0;
984 /* In this loop, we consider args in the order they are written.
985 We fill up ARGS from the front or from the back if necessary
986 so that in any case the first arg to be pushed ends up at the front. */
988 #ifdef PUSH_ARGS_REVERSED
989 i = num_actuals - 1, inc = -1;
990 /* In this case, must reverse order of args
991 so that we compute and push the last arg first. */
996 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
997 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
999 tree type = TREE_TYPE (TREE_VALUE (p));
1001 enum machine_mode mode;
1003 args[i].tree_value = TREE_VALUE (p);
1005 /* Replace erroneous argument with constant zero. */
1006 if (type == error_mark_node || TYPE_SIZE (type) == 0)
1007 args[i].tree_value = integer_zero_node, type = integer_type_node;
1009 /* If TYPE is a transparent union, pass things the way we would
1010 pass the first field of the union. We have already verified that
1011 the modes are the same. */
1012 if (TYPE_TRANSPARENT_UNION (type))
1013 type = TREE_TYPE (TYPE_FIELDS (type));
1015 /* Decide where to pass this arg.
1017 args[i].reg is nonzero if all or part is passed in registers.
1019 args[i].partial is nonzero if part but not all is passed in registers,
1020 and the exact value says how many words are passed in registers.
1022 args[i].pass_on_stack is nonzero if the argument must at least be
1023 computed on the stack. It may then be loaded back into registers
1024 if args[i].reg is nonzero.
1026 These decisions are driven by the FUNCTION_... macros and must agree
1027 with those made by function.c. */
1029 /* See if this argument should be passed by invisible reference. */
1030 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1031 && contains_placeholder_p (TYPE_SIZE (type)))
1032 || TREE_ADDRESSABLE (type)
1033 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1034 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, TYPE_MODE (type),
1035 type, argpos < n_named_args)
1039 #ifdef FUNCTION_ARG_CALLEE_COPIES
1040 if (FUNCTION_ARG_CALLEE_COPIES (args_so_far, TYPE_MODE (type), type,
1041 argpos < n_named_args)
1042 /* If it's in a register, we must make a copy of it too. */
1043 /* ??? Is this a sufficient test? Is there a better one? */
1044 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1045 && REG_P (DECL_RTL (args[i].tree_value)))
1046 && ! TREE_ADDRESSABLE (type))
1048 args[i].tree_value = build1 (ADDR_EXPR,
1049 build_pointer_type (type),
1050 args[i].tree_value);
1051 type = build_pointer_type (type);
1056 /* We make a copy of the object and pass the address to the
1057 function being called. */
1060 if (TYPE_SIZE (type) == 0
1061 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
1063 /* This is a variable-sized object. Make space on the stack
1065 rtx size_rtx = expr_size (TREE_VALUE (p));
1067 if (old_stack_level == 0)
1069 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1070 old_pending_adj = pending_stack_adjust;
1071 pending_stack_adjust = 0;
1074 copy = gen_rtx (MEM, BLKmode,
1075 allocate_dynamic_stack_space (size_rtx,
1077 TYPE_ALIGN (type)));
1081 int size = int_size_in_bytes (type);
1082 copy = assign_stack_temp (TYPE_MODE (type), size, 0);
1085 MEM_IN_STRUCT_P (copy) = AGGREGATE_TYPE_P (type);
1087 store_expr (args[i].tree_value, copy, 0);
1089 args[i].tree_value = build1 (ADDR_EXPR,
1090 build_pointer_type (type),
1091 make_tree (type, copy));
1092 type = build_pointer_type (type);
1096 mode = TYPE_MODE (type);
1097 unsignedp = TREE_UNSIGNED (type);
1099 #ifdef PROMOTE_FUNCTION_ARGS
1100 mode = promote_mode (type, mode, &unsignedp, 1);
1103 args[i].unsignedp = unsignedp;
1104 args[i].mode = mode;
1105 args[i].reg = FUNCTION_ARG (args_so_far, mode, type,
1106 argpos < n_named_args);
1107 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1110 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, type,
1111 argpos < n_named_args);
1114 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1116 /* If FUNCTION_ARG returned an (expr_list (nil) FOO), it means that
1117 we are to pass this arg in the register(s) designated by FOO, but
1118 also to pass it in the stack. */
1119 if (args[i].reg && GET_CODE (args[i].reg) == EXPR_LIST
1120 && XEXP (args[i].reg, 0) == 0)
1121 args[i].pass_on_stack = 1, args[i].reg = XEXP (args[i].reg, 1);
1123 /* If this is an addressable type, we must preallocate the stack
1124 since we must evaluate the object into its final location.
1126 If this is to be passed in both registers and the stack, it is simpler
1128 if (TREE_ADDRESSABLE (type)
1129 || (args[i].pass_on_stack && args[i].reg != 0))
1130 must_preallocate = 1;
1132 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1133 we cannot consider this function call constant. */
1134 if (TREE_ADDRESSABLE (type))
1137 /* Compute the stack-size of this argument. */
1138 if (args[i].reg == 0 || args[i].partial != 0
1139 #ifdef REG_PARM_STACK_SPACE
1140 || reg_parm_stack_space > 0
1142 || args[i].pass_on_stack)
1143 locate_and_pad_parm (mode, type,
1144 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1149 fndecl, &args_size, &args[i].offset,
1152 #ifndef ARGS_GROW_DOWNWARD
1153 args[i].slot_offset = args_size;
1156 #ifndef REG_PARM_STACK_SPACE
1157 /* If a part of the arg was put into registers,
1158 don't include that part in the amount pushed. */
1159 if (! args[i].pass_on_stack)
1160 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1161 / (PARM_BOUNDARY / BITS_PER_UNIT)
1162 * (PARM_BOUNDARY / BITS_PER_UNIT));
1165 /* Update ARGS_SIZE, the total stack space for args so far. */
1167 args_size.constant += args[i].size.constant;
1168 if (args[i].size.var)
1170 ADD_PARM_SIZE (args_size, args[i].size.var);
1173 /* Since the slot offset points to the bottom of the slot,
1174 we must record it after incrementing if the args grow down. */
1175 #ifdef ARGS_GROW_DOWNWARD
1176 args[i].slot_offset = args_size;
1178 args[i].slot_offset.constant = -args_size.constant;
1181 SUB_PARM_SIZE (args[i].slot_offset, args_size.var);
1185 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1186 have been used, etc. */
1188 FUNCTION_ARG_ADVANCE (args_so_far, TYPE_MODE (type), type,
1189 argpos < n_named_args);
1192 #ifdef FINAL_REG_PARM_STACK_SPACE
1193 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
1197 /* Compute the actual size of the argument block required. The variable
1198 and constant sizes must be combined, the size may have to be rounded,
1199 and there may be a minimum required size. */
1201 original_args_size = args_size;
1204 /* If this function requires a variable-sized argument list, don't try to
1205 make a cse'able block for this call. We may be able to do this
1206 eventually, but it is too complicated to keep track of what insns go
1207 in the cse'able block and which don't. */
1210 must_preallocate = 1;
1212 args_size.var = ARGS_SIZE_TREE (args_size);
1213 args_size.constant = 0;
1215 #ifdef STACK_BOUNDARY
1216 if (STACK_BOUNDARY != BITS_PER_UNIT)
1217 args_size.var = round_up (args_size.var, STACK_BYTES);
1220 #ifdef REG_PARM_STACK_SPACE
1221 if (reg_parm_stack_space > 0)
1224 = size_binop (MAX_EXPR, args_size.var,
1225 size_int (REG_PARM_STACK_SPACE (fndecl)));
1227 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1228 /* The area corresponding to register parameters is not to count in
1229 the size of the block we need. So make the adjustment. */
1231 = size_binop (MINUS_EXPR, args_size.var,
1232 size_int (reg_parm_stack_space));
1239 #ifdef STACK_BOUNDARY
1240 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
1241 / STACK_BYTES) * STACK_BYTES);
1244 #ifdef REG_PARM_STACK_SPACE
1245 args_size.constant = MAX (args_size.constant,
1246 reg_parm_stack_space);
1247 #ifdef MAYBE_REG_PARM_STACK_SPACE
1248 if (reg_parm_stack_space == 0)
1249 args_size.constant = 0;
1251 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1252 args_size.constant -= reg_parm_stack_space;
1257 /* See if we have or want to preallocate stack space.
1259 If we would have to push a partially-in-regs parm
1260 before other stack parms, preallocate stack space instead.
1262 If the size of some parm is not a multiple of the required stack
1263 alignment, we must preallocate.
1265 If the total size of arguments that would otherwise create a copy in
1266 a temporary (such as a CALL) is more than half the total argument list
1267 size, preallocation is faster.
1269 Another reason to preallocate is if we have a machine (like the m88k)
1270 where stack alignment is required to be maintained between every
1271 pair of insns, not just when the call is made. However, we assume here
1272 that such machines either do not have push insns (and hence preallocation
1273 would occur anyway) or the problem is taken care of with
1276 if (! must_preallocate)
1278 int partial_seen = 0;
1279 int copy_to_evaluate_size = 0;
1281 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1283 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1285 else if (partial_seen && args[i].reg == 0)
1286 must_preallocate = 1;
1288 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1289 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1290 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1291 || TREE_CODE (args[i].tree_value) == COND_EXPR
1292 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1293 copy_to_evaluate_size
1294 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1297 if (copy_to_evaluate_size * 2 >= args_size.constant
1298 && args_size.constant > 0)
1299 must_preallocate = 1;
1302 /* If the structure value address will reference the stack pointer, we must
1303 stabilize it. We don't need to do this if we know that we are not going
1304 to adjust the stack pointer in processing this call. */
1306 if (structure_value_addr
1307 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
1308 || reg_mentioned_p (virtual_outgoing_args_rtx, structure_value_addr))
1310 #ifndef ACCUMULATE_OUTGOING_ARGS
1311 || args_size.constant
1314 structure_value_addr = copy_to_reg (structure_value_addr);
1316 /* If this function call is cse'able, precompute all the parameters.
1317 Note that if the parameter is constructed into a temporary, this will
1318 cause an additional copy because the parameter will be constructed
1319 into a temporary location and then copied into the outgoing arguments.
1320 If a parameter contains a call to alloca and this function uses the
1321 stack, precompute the parameter. */
1323 /* If we preallocated the stack space, and some arguments must be passed
1324 on the stack, then we must precompute any parameter which contains a
1325 function call which will store arguments on the stack.
1326 Otherwise, evaluating the parameter may clobber previous parameters
1327 which have already been stored into the stack. */
1329 for (i = 0; i < num_actuals; i++)
1331 || ((args_size.var != 0 || args_size.constant != 0)
1332 && calls_function (args[i].tree_value, 1))
1333 || (must_preallocate && (args_size.var != 0 || args_size.constant != 0)
1334 && calls_function (args[i].tree_value, 0)))
1336 /* If this is an addressable type, we cannot pre-evaluate it. */
1337 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1342 args[i].initial_value = args[i].value
1343 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1345 preserve_temp_slots (args[i].value);
1348 /* ANSI doesn't require a sequence point here,
1349 but PCC has one, so this will avoid some problems. */
1352 args[i].initial_value = args[i].value
1353 = protect_from_queue (args[i].initial_value, 0);
1355 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) != args[i].mode)
1357 = convert_modes (args[i].mode,
1358 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1359 args[i].value, args[i].unsignedp);
1362 /* Now we are about to start emitting insns that can be deleted
1363 if a libcall is deleted. */
1367 /* If we have no actual push instructions, or shouldn't use them,
1368 make space for all args right now. */
1370 if (args_size.var != 0)
1372 if (old_stack_level == 0)
1374 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1375 old_pending_adj = pending_stack_adjust;
1376 pending_stack_adjust = 0;
1377 #ifdef ACCUMULATE_OUTGOING_ARGS
1378 /* stack_arg_under_construction says whether a stack arg is
1379 being constructed at the old stack level. Pushing the stack
1380 gets a clean outgoing argument block. */
1381 old_stack_arg_under_construction = stack_arg_under_construction;
1382 stack_arg_under_construction = 0;
1385 argblock = push_block (ARGS_SIZE_RTX (args_size), 0, 0);
1389 /* Note that we must go through the motions of allocating an argument
1390 block even if the size is zero because we may be storing args
1391 in the area reserved for register arguments, which may be part of
1394 int needed = args_size.constant;
1396 /* Store the maximum argument space used. It will be pushed by the
1397 prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow checking). */
1399 if (needed > current_function_outgoing_args_size)
1400 current_function_outgoing_args_size = needed;
1402 if (must_preallocate)
1404 #ifdef ACCUMULATE_OUTGOING_ARGS
1405 /* Since the stack pointer will never be pushed, it is possible for
1406 the evaluation of a parm to clobber something we have already
1407 written to the stack. Since most function calls on RISC machines
1408 do not use the stack, this is uncommon, but must work correctly.
1410 Therefore, we save any area of the stack that was already written
1411 and that we are using. Here we set up to do this by making a new
1412 stack usage map from the old one. The actual save will be done
1415 Another approach might be to try to reorder the argument
1416 evaluations to avoid this conflicting stack usage. */
1418 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1419 /* Since we will be writing into the entire argument area, the
1420 map must be allocated for its entire size, not just the part that
1421 is the responsibility of the caller. */
1422 needed += reg_parm_stack_space;
1425 #ifdef ARGS_GROW_DOWNWARD
1426 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
1429 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
1432 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
1434 if (initial_highest_arg_in_use)
1435 bcopy (initial_stack_usage_map, stack_usage_map,
1436 initial_highest_arg_in_use);
1438 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
1439 bzero (&stack_usage_map[initial_highest_arg_in_use],
1440 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
1443 /* The address of the outgoing argument list must not be copied to a
1444 register here, because argblock would be left pointing to the
1445 wrong place after the call to allocate_dynamic_stack_space below.
1448 argblock = virtual_outgoing_args_rtx;
1450 #else /* not ACCUMULATE_OUTGOING_ARGS */
1451 if (inhibit_defer_pop == 0)
1453 /* Try to reuse some or all of the pending_stack_adjust
1454 to get this space. Maybe we can avoid any pushing. */
1455 if (needed > pending_stack_adjust)
1457 needed -= pending_stack_adjust;
1458 pending_stack_adjust = 0;
1462 pending_stack_adjust -= needed;
1466 /* Special case this because overhead of `push_block' in this
1467 case is non-trivial. */
1469 argblock = virtual_outgoing_args_rtx;
1471 argblock = push_block (GEN_INT (needed), 0, 0);
1473 /* We only really need to call `copy_to_reg' in the case where push
1474 insns are going to be used to pass ARGBLOCK to a function
1475 call in ARGS. In that case, the stack pointer changes value
1476 from the allocation point to the call point, and hence
1477 the value of VIRTUAL_OUTGOING_ARGS_RTX changes as well.
1478 But might as well always do it. */
1479 argblock = copy_to_reg (argblock);
1480 #endif /* not ACCUMULATE_OUTGOING_ARGS */
1484 #ifdef ACCUMULATE_OUTGOING_ARGS
1485 /* The save/restore code in store_one_arg handles all cases except one:
1486 a constructor call (including a C function returning a BLKmode struct)
1487 to initialize an argument. */
1488 if (stack_arg_under_construction)
1490 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1491 rtx push_size = GEN_INT (reg_parm_stack_space + args_size.constant);
1493 rtx push_size = GEN_INT (args_size.constant);
1495 if (old_stack_level == 0)
1497 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1498 old_pending_adj = pending_stack_adjust;
1499 pending_stack_adjust = 0;
1500 /* stack_arg_under_construction says whether a stack arg is
1501 being constructed at the old stack level. Pushing the stack
1502 gets a clean outgoing argument block. */
1503 old_stack_arg_under_construction = stack_arg_under_construction;
1504 stack_arg_under_construction = 0;
1505 /* Make a new map for the new argument list. */
1506 stack_usage_map = (char *)alloca (highest_outgoing_arg_in_use);
1507 bzero (stack_usage_map, highest_outgoing_arg_in_use);
1508 highest_outgoing_arg_in_use = 0;
1510 allocate_dynamic_stack_space (push_size, NULL_RTX, BITS_PER_UNIT);
1512 /* If argument evaluation might modify the stack pointer, copy the
1513 address of the argument list to a register. */
1514 for (i = 0; i < num_actuals; i++)
1515 if (args[i].pass_on_stack)
1517 argblock = copy_addr_to_reg (argblock);
1523 /* If we preallocated stack space, compute the address of each argument.
1524 We need not ensure it is a valid memory address here; it will be
1525 validized when it is used. */
1528 rtx arg_reg = argblock;
1531 if (GET_CODE (argblock) == PLUS)
1532 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1534 for (i = 0; i < num_actuals; i++)
1536 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1537 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1540 /* Skip this parm if it will not be passed on the stack. */
1541 if (! args[i].pass_on_stack && args[i].reg != 0)
1544 if (GET_CODE (offset) == CONST_INT)
1545 addr = plus_constant (arg_reg, INTVAL (offset));
1547 addr = gen_rtx (PLUS, Pmode, arg_reg, offset);
1549 addr = plus_constant (addr, arg_offset);
1550 args[i].stack = gen_rtx (MEM, args[i].mode, addr);
1551 MEM_IN_STRUCT_P (args[i].stack)
1552 = AGGREGATE_TYPE_P (TREE_TYPE (args[i].tree_value));
1554 if (GET_CODE (slot_offset) == CONST_INT)
1555 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1557 addr = gen_rtx (PLUS, Pmode, arg_reg, slot_offset);
1559 addr = plus_constant (addr, arg_offset);
1560 args[i].stack_slot = gen_rtx (MEM, args[i].mode, addr);
1564 #ifdef PUSH_ARGS_REVERSED
1565 #ifdef STACK_BOUNDARY
1566 /* If we push args individually in reverse order, perform stack alignment
1567 before the first push (the last arg). */
1569 anti_adjust_stack (GEN_INT (args_size.constant
1570 - original_args_size.constant));
1574 /* Don't try to defer pops if preallocating, not even from the first arg,
1575 since ARGBLOCK probably refers to the SP. */
1579 /* Get the function to call, in the form of RTL. */
1582 /* If this is the first use of the function, see if we need to
1583 make an external definition for it. */
1584 if (! TREE_USED (fndecl))
1586 assemble_external (fndecl);
1587 TREE_USED (fndecl) = 1;
1590 /* Get a SYMBOL_REF rtx for the function address. */
1591 funexp = XEXP (DECL_RTL (fndecl), 0);
1594 /* Generate an rtx (probably a pseudo-register) for the address. */
1597 funexp = expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1598 pop_temp_slots (); /* FUNEXP can't be BLKmode */
1602 /* Figure out the register where the value, if any, will come back. */
1604 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
1605 && ! structure_value_addr)
1607 if (pcc_struct_value)
1608 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
1611 valreg = hard_function_value (TREE_TYPE (exp), fndecl);
1614 /* Precompute all register parameters. It isn't safe to compute anything
1615 once we have started filling any specific hard regs. */
1617 for (i = 0; i < num_actuals; i++)
1618 if (args[i].reg != 0 && ! args[i].pass_on_stack)
1622 if (args[i].value == 0)
1625 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
1627 preserve_temp_slots (args[i].value);
1630 /* ANSI doesn't require a sequence point here,
1631 but PCC has one, so this will avoid some problems. */
1635 /* If we are to promote the function arg to a wider mode,
1638 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
1640 = convert_modes (args[i].mode,
1641 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1642 args[i].value, args[i].unsignedp);
1644 /* If the value is expensive, and we are inside an appropriately
1645 short loop, put the value into a pseudo and then put the pseudo
1648 For small register classes, also do this if this call uses
1649 register parameters. This is to avoid reload conflicts while
1650 loading the parameters registers. */
1652 if ((! (GET_CODE (args[i].value) == REG
1653 || (GET_CODE (args[i].value) == SUBREG
1654 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
1655 && args[i].mode != BLKmode
1656 && rtx_cost (args[i].value, SET) > 2
1657 #ifdef SMALL_REGISTER_CLASSES
1658 && (reg_parm_seen || preserve_subexpressions_p ())
1660 && preserve_subexpressions_p ()
1663 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
1666 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
1667 /* The argument list is the property of the called routine and it
1668 may clobber it. If the fixed area has been used for previous
1669 parameters, we must save and restore it.
1671 Here we compute the boundary of the that needs to be saved, if any. */
1673 #ifdef ARGS_GROW_DOWNWARD
1674 for (i = 0; i < reg_parm_stack_space + 1; i++)
1676 for (i = 0; i < reg_parm_stack_space; i++)
1679 if (i >= highest_outgoing_arg_in_use
1680 || stack_usage_map[i] == 0)
1683 if (low_to_save == -1)
1689 if (low_to_save >= 0)
1691 int num_to_save = high_to_save - low_to_save + 1;
1692 enum machine_mode save_mode
1693 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
1696 /* If we don't have the required alignment, must do this in BLKmode. */
1697 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
1698 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
1699 save_mode = BLKmode;
1701 stack_area = gen_rtx (MEM, save_mode,
1702 memory_address (save_mode,
1704 #ifdef ARGS_GROW_DOWNWARD
1705 plus_constant (argblock,
1708 plus_constant (argblock,
1712 if (save_mode == BLKmode)
1714 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
1715 MEM_IN_STRUCT_P (save_area) = 0;
1716 emit_block_move (validize_mem (save_area), stack_area,
1717 GEN_INT (num_to_save),
1718 PARM_BOUNDARY / BITS_PER_UNIT);
1722 save_area = gen_reg_rtx (save_mode);
1723 emit_move_insn (save_area, stack_area);
1729 /* Now store (and compute if necessary) all non-register parms.
1730 These come before register parms, since they can require block-moves,
1731 which could clobber the registers used for register parms.
1732 Parms which have partial registers are not stored here,
1733 but we do preallocate space here if they want that. */
1735 for (i = 0; i < num_actuals; i++)
1736 if (args[i].reg == 0 || args[i].pass_on_stack)
1737 store_one_arg (&args[i], argblock, may_be_alloca,
1738 args_size.var != 0, fndecl, reg_parm_stack_space);
1740 /* If we have a parm that is passed in registers but not in memory
1741 and whose alignment does not permit a direct copy into registers,
1742 make a group of pseudos that correspond to each register that we
1745 if (STRICT_ALIGNMENT)
1746 for (i = 0; i < num_actuals; i++)
1747 if (args[i].reg != 0 && ! args[i].pass_on_stack
1748 && args[i].mode == BLKmode
1749 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1750 < MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1752 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1753 int big_endian_correction = 0;
1755 args[i].n_aligned_regs
1756 = args[i].partial ? args[i].partial
1757 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1759 args[i].aligned_regs = (rtx *) alloca (sizeof (rtx)
1760 * args[i].n_aligned_regs);
1762 /* Structures smaller than a word are aligned to the least
1763 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1764 this means we must skip the empty high order bytes when
1765 calculating the bit offset. */
1766 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
1767 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1769 for (j = 0; j < args[i].n_aligned_regs; j++)
1771 rtx reg = gen_reg_rtx (word_mode);
1772 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1773 int bitsize = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
1776 args[i].aligned_regs[j] = reg;
1778 /* Clobber REG and move each partword into it. Ensure we don't
1779 go past the end of the structure. Note that the loop below
1780 works because we've already verified that padding
1781 and endianness are compatible. */
1783 emit_insn (gen_rtx (CLOBBER, VOIDmode, reg));
1786 bitpos < BITS_PER_WORD && bytes > 0;
1787 bitpos += bitsize, bytes -= bitsize / BITS_PER_UNIT)
1789 int xbitpos = bitpos + big_endian_correction;
1791 store_bit_field (reg, bitsize, xbitpos, word_mode,
1792 extract_bit_field (word, bitsize, bitpos, 1,
1793 NULL_RTX, word_mode,
1795 bitsize / BITS_PER_UNIT,
1797 bitsize / BITS_PER_UNIT, BITS_PER_WORD);
1802 /* Now store any partially-in-registers parm.
1803 This is the last place a block-move can happen. */
1805 for (i = 0; i < num_actuals; i++)
1806 if (args[i].partial != 0 && ! args[i].pass_on_stack)
1807 store_one_arg (&args[i], argblock, may_be_alloca,
1808 args_size.var != 0, fndecl, reg_parm_stack_space);
1810 #ifndef PUSH_ARGS_REVERSED
1811 #ifdef STACK_BOUNDARY
1812 /* If we pushed args in forward order, perform stack alignment
1813 after pushing the last arg. */
1815 anti_adjust_stack (GEN_INT (args_size.constant
1816 - original_args_size.constant));
1820 /* If register arguments require space on the stack and stack space
1821 was not preallocated, allocate stack space here for arguments
1822 passed in registers. */
1823 #if ! defined(ACCUMULATE_OUTGOING_ARGS) && defined(OUTGOING_REG_PARM_STACK_SPACE)
1824 if (must_preallocate == 0 && reg_parm_stack_space > 0)
1825 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
1828 /* Pass the function the address in which to return a structure value. */
1829 if (structure_value_addr && ! structure_value_addr_parm)
1831 emit_move_insn (struct_value_rtx,
1833 force_operand (structure_value_addr,
1835 if (GET_CODE (struct_value_rtx) == REG)
1836 use_reg (&call_fusage, struct_value_rtx);
1839 funexp = prepare_call_address (funexp, fndecl, &call_fusage, reg_parm_seen);
1841 /* Now do the register loads required for any wholly-register parms or any
1842 parms which are passed both on the stack and in a register. Their
1843 expressions were already evaluated.
1845 Mark all register-parms as living through the call, putting these USE
1846 insns in the CALL_INSN_FUNCTION_USAGE field. */
1848 for (i = 0; i < num_actuals; i++)
1850 rtx list = args[i].reg;
1851 int partial = args[i].partial;
1858 /* Process each register that needs to get this arg. */
1859 if (GET_CODE (list) == EXPR_LIST)
1860 reg = XEXP (list, 0), list = XEXP (list, 1);
1862 reg = list, list = 0;
1864 /* Set to non-negative if must move a word at a time, even if just
1865 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1866 we just use a normal move insn. This value can be zero if the
1867 argument is a zero size structure with no fields. */
1868 nregs = (partial ? partial
1869 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1870 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1871 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1874 /* If simple case, just do move. If normal partial, store_one_arg
1875 has already loaded the register for us. In all other cases,
1876 load the register(s) from memory. */
1879 emit_move_insn (reg, args[i].value);
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]);
1889 else if (args[i].partial == 0 || args[i].pass_on_stack)
1890 move_block_to_reg (REGNO (reg),
1891 validize_mem (args[i].value), nregs,
1895 use_reg (&call_fusage, reg);
1897 use_regs (&call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1899 /* PARTIAL referred only to the first register, so clear it for the
1905 /* Perform postincrements before actually calling the function. */
1908 /* All arguments and registers used for the call must be set up by now! */
1910 /* Generate the actual call instruction. */
1911 emit_call_1 (funexp, fndecl, funtype, args_size.constant, struct_value_size,
1912 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
1913 valreg, old_inhibit_defer_pop, call_fusage, is_const);
1915 /* If call is cse'able, make appropriate pair of reg-notes around it.
1916 Test valreg so we don't crash; may safely ignore `const'
1917 if return type is void. */
1918 if (is_const && valreg != 0)
1921 rtx temp = gen_reg_rtx (GET_MODE (valreg));
1924 /* Construct an "equal form" for the value which mentions all the
1925 arguments in order as well as the function name. */
1926 #ifdef PUSH_ARGS_REVERSED
1927 for (i = 0; i < num_actuals; i++)
1928 note = gen_rtx (EXPR_LIST, VOIDmode, args[i].initial_value, note);
1930 for (i = num_actuals - 1; i >= 0; i--)
1931 note = gen_rtx (EXPR_LIST, VOIDmode, args[i].initial_value, note);
1933 note = gen_rtx (EXPR_LIST, VOIDmode, funexp, note);
1935 insns = get_insns ();
1938 emit_libcall_block (insns, temp, valreg, note);
1944 /* Otherwise, just write out the sequence without a note. */
1945 rtx insns = get_insns ();
1951 /* For calls to `setjmp', etc., inform flow.c it should complain
1952 if nonvolatile values are live. */
1956 emit_note (name, NOTE_INSN_SETJMP);
1957 current_function_calls_setjmp = 1;
1961 current_function_calls_longjmp = 1;
1963 /* Notice functions that cannot return.
1964 If optimizing, insns emitted below will be dead.
1965 If not optimizing, they will exist, which is useful
1966 if the user uses the `return' command in the debugger. */
1968 if (is_volatile || is_longjmp)
1971 /* If value type not void, return an rtx for the value. */
1973 /* If there are cleanups to be called, don't use a hard reg as target. */
1974 if (cleanups_this_call != old_cleanups
1975 && target && REG_P (target)
1976 && REGNO (target) < FIRST_PSEUDO_REGISTER)
1979 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
1982 target = const0_rtx;
1984 else if (structure_value_addr)
1986 if (target == 0 || GET_CODE (target) != MEM)
1988 target = gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)),
1989 memory_address (TYPE_MODE (TREE_TYPE (exp)),
1990 structure_value_addr));
1991 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
1994 else if (pcc_struct_value)
1998 /* We used leave the value in the location that it is
1999 returned in, but that causes problems if it is used more
2000 than once in one expression. Rather than trying to track
2001 when a copy is required, we always copy when TARGET is
2002 not specified. This calling sequence is only used on
2003 a few machines and TARGET is usually nonzero. */
2004 if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
2006 target = assign_stack_temp (BLKmode,
2007 int_size_in_bytes (TREE_TYPE (exp)),
2010 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
2012 /* Save this temp slot around the pop below. */
2013 preserve_temp_slots (target);
2016 target = gen_reg_rtx (TYPE_MODE (TREE_TYPE (exp)));
2019 if (TYPE_MODE (TREE_TYPE (exp)) != BLKmode)
2020 emit_move_insn (target, gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)),
2021 copy_to_reg (valreg)));
2023 emit_block_move (target, gen_rtx (MEM, BLKmode, copy_to_reg (valreg)),
2025 TYPE_ALIGN (TREE_TYPE (exp)) / BITS_PER_UNIT);
2027 else if (target && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
2028 && GET_MODE (target) == GET_MODE (valreg))
2029 /* TARGET and VALREG cannot be equal at this point because the latter
2030 would not have REG_FUNCTION_VALUE_P true, while the former would if
2031 it were referring to the same register.
2033 If they refer to the same register, this move will be a no-op, except
2034 when function inlining is being done. */
2035 emit_move_insn (target, valreg);
2036 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
2038 /* Some machines (the PA for example) want to return all small
2039 structures in registers regardless of the structure's alignment.
2041 Deal with them explicitly by copying from the return registers
2042 into the target MEM locations. */
2043 int bytes = int_size_in_bytes (TREE_TYPE (exp));
2044 int n_regs = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
2046 enum machine_mode tmpmode;
2048 int bitsize = MIN (TYPE_ALIGN (TREE_TYPE (exp)), BITS_PER_WORD);
2049 int bitpos, xbitpos, big_endian_correction = 0;
2053 target = assign_stack_temp (BLKmode, bytes, 0);
2054 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
2055 preserve_temp_slots (target);
2058 /* This code assumes valreg is at least a full word. If it isn't,
2059 copy it into a new pseudo which is a full word. */
2060 if (GET_MODE (valreg) != BLKmode
2061 && GET_MODE_SIZE (GET_MODE (valreg)) < UNITS_PER_WORD)
2062 valreg = convert_to_mode (SImode, valreg,
2063 TREE_UNSIGNED (TREE_TYPE (exp)));
2065 /* Structures whose size is not a multiple of a word are aligned
2066 to the least significant byte (to the right). On a BYTES_BIG_ENDIAN
2067 machine, this means we must skip the empty high order bytes when
2068 calculating the bit offset. */
2069 if (BYTES_BIG_ENDIAN && bytes % UNITS_PER_WORD)
2070 big_endian_correction = (BITS_PER_WORD - ((bytes % UNITS_PER_WORD)
2073 /* Copy the structure BITSIZE bites at a time.
2075 We could probably emit more efficient code for machines
2076 which do not use strict alignment, but it doesn't seem
2077 worth the effort at the current time. */
2078 for (bitpos = 0, xbitpos = big_endian_correction;
2079 bitpos < bytes * BITS_PER_UNIT;
2080 bitpos += bitsize, xbitpos += bitsize)
2083 /* We need a new source operand each time xbitpos is on a
2084 word boundary and when xbitpos == big_endian_correction
2085 (the first time through). */
2086 if (xbitpos % BITS_PER_WORD == 0
2087 || xbitpos == big_endian_correction)
2088 src = operand_subword_force (valreg,
2089 xbitpos / BITS_PER_WORD,
2092 /* We need a new destination operand each time bitpos is on
2094 if (bitpos % BITS_PER_WORD == 0)
2095 dst = operand_subword (target, bitpos / BITS_PER_WORD, 1, BLKmode);
2097 /* Use xbitpos for the source extraction (right justified) and
2098 xbitpos for the destination store (left justified). */
2099 store_bit_field (dst, bitsize, bitpos % BITS_PER_WORD, word_mode,
2100 extract_bit_field (src, bitsize,
2101 xbitpos % BITS_PER_WORD, 1,
2102 NULL_RTX, word_mode,
2104 bitsize / BITS_PER_UNIT,
2106 bitsize / BITS_PER_UNIT, BITS_PER_WORD);
2110 target = copy_to_reg (valreg);
2112 #ifdef PROMOTE_FUNCTION_RETURN
2113 /* If we promoted this return value, make the proper SUBREG. TARGET
2114 might be const0_rtx here, so be careful. */
2115 if (GET_CODE (target) == REG
2116 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
2117 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
2119 tree type = TREE_TYPE (exp);
2120 int unsignedp = TREE_UNSIGNED (type);
2122 /* If we don't promote as expected, something is wrong. */
2123 if (GET_MODE (target)
2124 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
2127 target = gen_rtx (SUBREG, TYPE_MODE (type), target, 0);
2128 SUBREG_PROMOTED_VAR_P (target) = 1;
2129 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
2133 if (flag_short_temps)
2135 /* Perform all cleanups needed for the arguments of this call
2136 (i.e. destructors in C++). */
2137 expand_cleanups_to (old_cleanups);
2140 /* If size of args is variable or this was a constructor call for a stack
2141 argument, restore saved stack-pointer value. */
2143 if (old_stack_level)
2145 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
2146 pending_stack_adjust = old_pending_adj;
2147 #ifdef ACCUMULATE_OUTGOING_ARGS
2148 stack_arg_under_construction = old_stack_arg_under_construction;
2149 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2150 stack_usage_map = initial_stack_usage_map;
2153 #ifdef ACCUMULATE_OUTGOING_ARGS
2156 #ifdef REG_PARM_STACK_SPACE
2159 enum machine_mode save_mode = GET_MODE (save_area);
2161 = gen_rtx (MEM, save_mode,
2162 memory_address (save_mode,
2163 #ifdef ARGS_GROW_DOWNWARD
2164 plus_constant (argblock, - high_to_save)
2166 plus_constant (argblock, low_to_save)
2170 if (save_mode != BLKmode)
2171 emit_move_insn (stack_area, save_area);
2173 emit_block_move (stack_area, validize_mem (save_area),
2174 GEN_INT (high_to_save - low_to_save + 1),
2175 PARM_BOUNDARY / BITS_PER_UNIT);
2179 /* If we saved any argument areas, restore them. */
2180 for (i = 0; i < num_actuals; i++)
2181 if (args[i].save_area)
2183 enum machine_mode save_mode = GET_MODE (args[i].save_area);
2185 = gen_rtx (MEM, save_mode,
2186 memory_address (save_mode,
2187 XEXP (args[i].stack_slot, 0)));
2189 if (save_mode != BLKmode)
2190 emit_move_insn (stack_area, args[i].save_area);
2192 emit_block_move (stack_area, validize_mem (args[i].save_area),
2193 GEN_INT (args[i].size.constant),
2194 PARM_BOUNDARY / BITS_PER_UNIT);
2197 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2198 stack_usage_map = initial_stack_usage_map;
2202 /* If this was alloca, record the new stack level for nonlocal gotos.
2203 Check for the handler slots since we might not have a save area
2204 for non-local gotos. */
2206 if (may_be_alloca && nonlocal_goto_handler_slot != 0)
2207 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
2214 /* Output a library call to function FUN (a SYMBOL_REF rtx)
2215 (emitting the queue unless NO_QUEUE is nonzero),
2216 for a value of mode OUTMODE,
2217 with NARGS different arguments, passed as alternating rtx values
2218 and machine_modes to convert them to.
2219 The rtx values should have been passed through protect_from_queue already.
2221 NO_QUEUE will be true if and only if the library call is a `const' call
2222 which will be enclosed in REG_LIBCALL/REG_RETVAL notes; it is equivalent
2223 to the variable is_const in expand_call.
2225 NO_QUEUE must be true for const calls, because if it isn't, then
2226 any pending increment will be emitted between REG_LIBCALL/REG_RETVAL notes,
2227 and will be lost if the libcall sequence is optimized away.
2229 NO_QUEUE must be false for non-const calls, because if it isn't, the
2230 call insn will have its CONST_CALL_P bit set, and it will be incorrectly
2231 optimized. For instance, the instruction scheduler may incorrectly
2232 move memory references across the non-const call. */
2235 emit_library_call VPROTO((rtx orgfun, int no_queue, enum machine_mode outmode,
2241 enum machine_mode outmode;
2245 /* Total size in bytes of all the stack-parms scanned so far. */
2246 struct args_size args_size;
2247 /* Size of arguments before any adjustments (such as rounding). */
2248 struct args_size original_args_size;
2249 register int argnum;
2254 CUMULATIVE_ARGS args_so_far;
2255 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2256 struct args_size offset; struct args_size size; };
2258 int old_inhibit_defer_pop = inhibit_defer_pop;
2259 rtx call_fusage = 0;
2260 /* library calls are never indirect calls. */
2261 int current_call_is_indirect = 0;
2263 VA_START (p, nargs);
2266 orgfun = va_arg (p, rtx);
2267 no_queue = va_arg (p, int);
2268 outmode = va_arg (p, enum machine_mode);
2269 nargs = va_arg (p, int);
2274 /* Copy all the libcall-arguments out of the varargs data
2275 and into a vector ARGVEC.
2277 Compute how to pass each argument. We only support a very small subset
2278 of the full argument passing conventions to limit complexity here since
2279 library functions shouldn't have many args. */
2281 argvec = (struct arg *) alloca (nargs * sizeof (struct arg));
2283 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun);
2285 args_size.constant = 0;
2290 for (count = 0; count < nargs; count++)
2292 rtx val = va_arg (p, rtx);
2293 enum machine_mode mode = va_arg (p, enum machine_mode);
2295 /* We cannot convert the arg value to the mode the library wants here;
2296 must do it earlier where we know the signedness of the arg. */
2298 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2301 /* On some machines, there's no way to pass a float to a library fcn.
2302 Pass it as a double instead. */
2303 #ifdef LIBGCC_NEEDS_DOUBLE
2304 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2305 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
2308 /* There's no need to call protect_from_queue, because
2309 either emit_move_insn or emit_push_insn will do that. */
2311 /* Make sure it is a reasonable operand for a move or push insn. */
2312 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2313 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2314 val = force_operand (val, NULL_RTX);
2316 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2317 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2319 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2320 be viewed as just an efficiency improvement. */
2321 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2322 emit_move_insn (slot, val);
2323 val = force_operand (XEXP (slot, 0), NULL_RTX);
2328 argvec[count].value = val;
2329 argvec[count].mode = mode;
2331 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2332 if (argvec[count].reg && GET_CODE (argvec[count].reg) == EXPR_LIST)
2334 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2335 argvec[count].partial
2336 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2338 argvec[count].partial = 0;
2341 locate_and_pad_parm (mode, NULL_TREE,
2342 argvec[count].reg && argvec[count].partial == 0,
2343 NULL_TREE, &args_size, &argvec[count].offset,
2344 &argvec[count].size);
2346 if (argvec[count].size.var)
2349 #ifndef REG_PARM_STACK_SPACE
2350 if (argvec[count].partial)
2351 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2354 if (argvec[count].reg == 0 || argvec[count].partial != 0
2355 #ifdef REG_PARM_STACK_SPACE
2359 args_size.constant += argvec[count].size.constant;
2361 #ifdef ACCUMULATE_OUTGOING_ARGS
2362 /* If this arg is actually passed on the stack, it might be
2363 clobbering something we already put there (this library call might
2364 be inside the evaluation of an argument to a function whose call
2365 requires the stack). This will only occur when the library call
2366 has sufficient args to run out of argument registers. Abort in
2367 this case; if this ever occurs, code must be added to save and
2368 restore the arg slot. */
2370 if (argvec[count].reg == 0 || argvec[count].partial != 0)
2374 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree)0, 1);
2378 /* If this machine requires an external definition for library
2379 functions, write one out. */
2380 assemble_external_libcall (fun);
2382 original_args_size = args_size;
2383 #ifdef STACK_BOUNDARY
2384 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2385 / STACK_BYTES) * STACK_BYTES);
2388 #ifdef REG_PARM_STACK_SPACE
2389 args_size.constant = MAX (args_size.constant,
2390 REG_PARM_STACK_SPACE (NULL_TREE));
2391 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2392 args_size.constant -= REG_PARM_STACK_SPACE (NULL_TREE);
2396 if (args_size.constant > current_function_outgoing_args_size)
2397 current_function_outgoing_args_size = args_size.constant;
2399 #ifdef ACCUMULATE_OUTGOING_ARGS
2400 args_size.constant = 0;
2403 #ifndef PUSH_ROUNDING
2404 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2407 #ifdef PUSH_ARGS_REVERSED
2408 #ifdef STACK_BOUNDARY
2409 /* If we push args individually in reverse order, perform stack alignment
2410 before the first push (the last arg). */
2412 anti_adjust_stack (GEN_INT (args_size.constant
2413 - original_args_size.constant));
2417 #ifdef PUSH_ARGS_REVERSED
2425 /* Push the args that need to be pushed. */
2427 for (count = 0; count < nargs; count++, argnum += inc)
2429 register enum machine_mode mode = argvec[argnum].mode;
2430 register rtx val = argvec[argnum].value;
2431 rtx reg = argvec[argnum].reg;
2432 int partial = argvec[argnum].partial;
2434 if (! (reg != 0 && partial == 0))
2435 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2436 argblock, GEN_INT (argvec[count].offset.constant));
2440 #ifndef PUSH_ARGS_REVERSED
2441 #ifdef STACK_BOUNDARY
2442 /* If we pushed args in forward order, perform stack alignment
2443 after pushing the last arg. */
2445 anti_adjust_stack (GEN_INT (args_size.constant
2446 - original_args_size.constant));
2450 #ifdef PUSH_ARGS_REVERSED
2456 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
2458 /* Now load any reg parms into their regs. */
2460 for (count = 0; count < nargs; count++, argnum += inc)
2462 register enum machine_mode mode = argvec[argnum].mode;
2463 register rtx val = argvec[argnum].value;
2464 rtx reg = argvec[argnum].reg;
2465 int partial = argvec[argnum].partial;
2467 if (reg != 0 && partial == 0)
2468 emit_move_insn (reg, val);
2472 /* For version 1.37, try deleting this entirely. */
2476 /* Any regs containing parms remain in use through the call. */
2477 for (count = 0; count < nargs; count++)
2478 if (argvec[count].reg != 0)
2479 use_reg (&call_fusage, argvec[count].reg);
2481 /* Don't allow popping to be deferred, since then
2482 cse'ing of library calls could delete a call and leave the pop. */
2485 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2486 will set inhibit_defer_pop to that value. */
2489 get_identifier (XSTR (orgfun, 0)),
2490 get_identifier (XSTR (orgfun, 0)), args_size.constant, 0,
2491 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2492 outmode != VOIDmode ? hard_libcall_value (outmode) : NULL_RTX,
2493 old_inhibit_defer_pop + 1, call_fusage, no_queue);
2497 /* Now restore inhibit_defer_pop to its actual original value. */
2501 /* Like emit_library_call except that an extra argument, VALUE,
2502 comes second and says where to store the result.
2503 (If VALUE is zero, this function chooses a convenient way
2504 to return the value.
2506 This function returns an rtx for where the value is to be found.
2507 If VALUE is nonzero, VALUE is returned. */
2510 emit_library_call_value VPROTO((rtx orgfun, rtx value, int no_queue,
2511 enum machine_mode outmode, int nargs, ...))
2517 enum machine_mode outmode;
2521 /* Total size in bytes of all the stack-parms scanned so far. */
2522 struct args_size args_size;
2523 /* Size of arguments before any adjustments (such as rounding). */
2524 struct args_size original_args_size;
2525 register int argnum;
2530 CUMULATIVE_ARGS args_so_far;
2531 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2532 struct args_size offset; struct args_size size; };
2534 int old_inhibit_defer_pop = inhibit_defer_pop;
2535 rtx call_fusage = 0;
2537 int pcc_struct_value = 0;
2538 int struct_value_size = 0;
2539 /* library calls are never indirect calls. */
2540 int current_call_is_indirect = 0;
2543 VA_START (p, nargs);
2546 orgfun = va_arg (p, rtx);
2547 value = va_arg (p, rtx);
2548 no_queue = va_arg (p, int);
2549 outmode = va_arg (p, enum machine_mode);
2550 nargs = va_arg (p, int);
2553 is_const = no_queue;
2556 /* If this kind of value comes back in memory,
2557 decide where in memory it should come back. */
2558 if (aggregate_value_p (type_for_mode (outmode, 0)))
2560 #ifdef PCC_STATIC_STRUCT_RETURN
2562 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
2564 mem_value = gen_rtx (MEM, outmode, pointer_reg);
2565 pcc_struct_value = 1;
2567 value = gen_reg_rtx (outmode);
2568 #else /* not PCC_STATIC_STRUCT_RETURN */
2569 struct_value_size = GET_MODE_SIZE (outmode);
2570 if (value != 0 && GET_CODE (value) == MEM)
2573 mem_value = assign_stack_temp (outmode, GET_MODE_SIZE (outmode), 0);
2576 /* This call returns a big structure. */
2580 /* ??? Unfinished: must pass the memory address as an argument. */
2582 /* Copy all the libcall-arguments out of the varargs data
2583 and into a vector ARGVEC.
2585 Compute how to pass each argument. We only support a very small subset
2586 of the full argument passing conventions to limit complexity here since
2587 library functions shouldn't have many args. */
2589 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
2591 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun);
2593 args_size.constant = 0;
2600 /* If there's a structure value address to be passed,
2601 either pass it in the special place, or pass it as an extra argument. */
2602 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
2604 rtx addr = XEXP (mem_value, 0);
2607 /* Make sure it is a reasonable operand for a move or push insn. */
2608 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
2609 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
2610 addr = force_operand (addr, NULL_RTX);
2612 argvec[count].value = addr;
2613 argvec[count].mode = Pmode;
2614 argvec[count].partial = 0;
2616 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
2617 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2618 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
2622 locate_and_pad_parm (Pmode, NULL_TREE,
2623 argvec[count].reg && argvec[count].partial == 0,
2624 NULL_TREE, &args_size, &argvec[count].offset,
2625 &argvec[count].size);
2628 if (argvec[count].reg == 0 || argvec[count].partial != 0
2629 #ifdef REG_PARM_STACK_SPACE
2633 args_size.constant += argvec[count].size.constant;
2635 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree)0, 1);
2640 for (; count < nargs; count++)
2642 rtx val = va_arg (p, rtx);
2643 enum machine_mode mode = va_arg (p, enum machine_mode);
2645 /* We cannot convert the arg value to the mode the library wants here;
2646 must do it earlier where we know the signedness of the arg. */
2648 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2651 /* On some machines, there's no way to pass a float to a library fcn.
2652 Pass it as a double instead. */
2653 #ifdef LIBGCC_NEEDS_DOUBLE
2654 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2655 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
2658 /* There's no need to call protect_from_queue, because
2659 either emit_move_insn or emit_push_insn will do that. */
2661 /* Make sure it is a reasonable operand for a move or push insn. */
2662 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2663 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2664 val = force_operand (val, NULL_RTX);
2666 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2667 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2669 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2670 be viewed as just an efficiency improvement. */
2671 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2672 emit_move_insn (slot, val);
2673 val = XEXP (slot, 0);
2678 argvec[count].value = val;
2679 argvec[count].mode = mode;
2681 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2682 if (argvec[count].reg && GET_CODE (argvec[count].reg) == EXPR_LIST)
2684 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2685 argvec[count].partial
2686 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2688 argvec[count].partial = 0;
2691 locate_and_pad_parm (mode, NULL_TREE,
2692 argvec[count].reg && argvec[count].partial == 0,
2693 NULL_TREE, &args_size, &argvec[count].offset,
2694 &argvec[count].size);
2696 if (argvec[count].size.var)
2699 #ifndef REG_PARM_STACK_SPACE
2700 if (argvec[count].partial)
2701 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2704 if (argvec[count].reg == 0 || argvec[count].partial != 0
2705 #ifdef REG_PARM_STACK_SPACE
2709 args_size.constant += argvec[count].size.constant;
2711 #ifdef ACCUMULATE_OUTGOING_ARGS
2712 /* If this arg is actually passed on the stack, it might be
2713 clobbering something we already put there (this library call might
2714 be inside the evaluation of an argument to a function whose call
2715 requires the stack). This will only occur when the library call
2716 has sufficient args to run out of argument registers. Abort in
2717 this case; if this ever occurs, code must be added to save and
2718 restore the arg slot. */
2720 if (argvec[count].reg == 0 || argvec[count].partial != 0)
2724 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree)0, 1);
2728 /* If this machine requires an external definition for library
2729 functions, write one out. */
2730 assemble_external_libcall (fun);
2732 original_args_size = args_size;
2733 #ifdef STACK_BOUNDARY
2734 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2735 / STACK_BYTES) * STACK_BYTES);
2738 #ifdef REG_PARM_STACK_SPACE
2739 args_size.constant = MAX (args_size.constant,
2740 REG_PARM_STACK_SPACE (NULL_TREE));
2741 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2742 args_size.constant -= REG_PARM_STACK_SPACE (NULL_TREE);
2746 if (args_size.constant > current_function_outgoing_args_size)
2747 current_function_outgoing_args_size = args_size.constant;
2749 #ifdef ACCUMULATE_OUTGOING_ARGS
2750 args_size.constant = 0;
2753 #ifndef PUSH_ROUNDING
2754 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2757 #ifdef PUSH_ARGS_REVERSED
2758 #ifdef STACK_BOUNDARY
2759 /* If we push args individually in reverse order, perform stack alignment
2760 before the first push (the last arg). */
2762 anti_adjust_stack (GEN_INT (args_size.constant
2763 - original_args_size.constant));
2767 #ifdef PUSH_ARGS_REVERSED
2775 /* Push the args that need to be pushed. */
2777 for (count = 0; count < nargs; count++, argnum += inc)
2779 register enum machine_mode mode = argvec[argnum].mode;
2780 register rtx val = argvec[argnum].value;
2781 rtx reg = argvec[argnum].reg;
2782 int partial = argvec[argnum].partial;
2784 if (! (reg != 0 && partial == 0))
2785 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2786 argblock, GEN_INT (argvec[count].offset.constant));
2790 #ifndef PUSH_ARGS_REVERSED
2791 #ifdef STACK_BOUNDARY
2792 /* If we pushed args in forward order, perform stack alignment
2793 after pushing the last arg. */
2795 anti_adjust_stack (GEN_INT (args_size.constant
2796 - original_args_size.constant));
2800 #ifdef PUSH_ARGS_REVERSED
2806 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
2808 /* Now load any reg parms into their regs. */
2810 for (count = 0; count < nargs; count++, argnum += inc)
2812 register enum machine_mode mode = argvec[argnum].mode;
2813 register rtx val = argvec[argnum].value;
2814 rtx reg = argvec[argnum].reg;
2815 int partial = argvec[argnum].partial;
2817 if (reg != 0 && partial == 0)
2818 emit_move_insn (reg, val);
2823 /* For version 1.37, try deleting this entirely. */
2828 /* Any regs containing parms remain in use through the call. */
2829 for (count = 0; count < nargs; count++)
2830 if (argvec[count].reg != 0)
2831 use_reg (&call_fusage, argvec[count].reg);
2833 /* Pass the function the address in which to return a structure value. */
2834 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
2836 emit_move_insn (struct_value_rtx,
2838 force_operand (XEXP (mem_value, 0),
2840 if (GET_CODE (struct_value_rtx) == REG)
2841 use_reg (&call_fusage, struct_value_rtx);
2844 /* Don't allow popping to be deferred, since then
2845 cse'ing of library calls could delete a call and leave the pop. */
2848 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2849 will set inhibit_defer_pop to that value. */
2852 get_identifier (XSTR (orgfun, 0)),
2853 get_identifier (XSTR (orgfun, 0)), args_size.constant,
2855 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2856 (outmode != VOIDmode && mem_value == 0
2857 ? hard_libcall_value (outmode) : NULL_RTX),
2858 old_inhibit_defer_pop + 1, call_fusage, is_const);
2860 /* Now restore inhibit_defer_pop to its actual original value. */
2865 /* Copy the value to the right place. */
2866 if (outmode != VOIDmode)
2872 if (value != mem_value)
2873 emit_move_insn (value, mem_value);
2875 else if (value != 0)
2876 emit_move_insn (value, hard_libcall_value (outmode));
2878 value = hard_libcall_value (outmode);
2885 /* Return an rtx which represents a suitable home on the stack
2886 given TYPE, the type of the argument looking for a home.
2887 This is called only for BLKmode arguments.
2889 SIZE is the size needed for this target.
2890 ARGS_ADDR is the address of the bottom of the argument block for this call.
2891 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
2892 if this machine uses push insns. */
2895 target_for_arg (type, size, args_addr, offset)
2899 struct args_size offset;
2902 rtx offset_rtx = ARGS_SIZE_RTX (offset);
2904 /* We do not call memory_address if possible,
2905 because we want to address as close to the stack
2906 as possible. For non-variable sized arguments,
2907 this will be stack-pointer relative addressing. */
2908 if (GET_CODE (offset_rtx) == CONST_INT)
2909 target = plus_constant (args_addr, INTVAL (offset_rtx));
2912 /* I have no idea how to guarantee that this
2913 will work in the presence of register parameters. */
2914 target = gen_rtx (PLUS, Pmode, args_addr, offset_rtx);
2915 target = memory_address (QImode, target);
2918 return gen_rtx (MEM, BLKmode, target);
2922 /* Store a single argument for a function call
2923 into the register or memory area where it must be passed.
2924 *ARG describes the argument value and where to pass it.
2926 ARGBLOCK is the address of the stack-block for all the arguments,
2927 or 0 on a machine where arguments are pushed individually.
2929 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
2930 so must be careful about how the stack is used.
2932 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
2933 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
2934 that we need not worry about saving and restoring the stack.
2936 FNDECL is the declaration of the function we are calling. */
2939 store_one_arg (arg, argblock, may_be_alloca, variable_size, fndecl,
2940 reg_parm_stack_space)
2941 struct arg_data *arg;
2946 int reg_parm_stack_space;
2948 register tree pval = arg->tree_value;
2952 int i, lower_bound, upper_bound;
2954 if (TREE_CODE (pval) == ERROR_MARK)
2957 /* Push a new temporary level for any temporaries we make for
2961 #ifdef ACCUMULATE_OUTGOING_ARGS
2962 /* If this is being stored into a pre-allocated, fixed-size, stack area,
2963 save any previous data at that location. */
2964 if (argblock && ! variable_size && arg->stack)
2966 #ifdef ARGS_GROW_DOWNWARD
2967 /* stack_slot is negative, but we want to index stack_usage_map */
2968 /* with positive values. */
2969 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
2970 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
2974 lower_bound = upper_bound - arg->size.constant;
2976 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
2977 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
2981 upper_bound = lower_bound + arg->size.constant;
2984 for (i = lower_bound; i < upper_bound; i++)
2985 if (stack_usage_map[i]
2986 #ifdef REG_PARM_STACK_SPACE
2987 /* Don't store things in the fixed argument area at this point;
2988 it has already been saved. */
2989 && i > reg_parm_stack_space
2994 if (i != upper_bound)
2996 /* We need to make a save area. See what mode we can make it. */
2997 enum machine_mode save_mode
2998 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
3000 = gen_rtx (MEM, save_mode,
3001 memory_address (save_mode, XEXP (arg->stack_slot, 0)));
3003 if (save_mode == BLKmode)
3005 arg->save_area = assign_stack_temp (BLKmode,
3006 arg->size.constant, 0);
3007 MEM_IN_STRUCT_P (arg->save_area)
3008 = AGGREGATE_TYPE_P (TREE_TYPE (arg->tree_value));
3009 preserve_temp_slots (arg->save_area);
3010 emit_block_move (validize_mem (arg->save_area), stack_area,
3011 GEN_INT (arg->size.constant),
3012 PARM_BOUNDARY / BITS_PER_UNIT);
3016 arg->save_area = gen_reg_rtx (save_mode);
3017 emit_move_insn (arg->save_area, stack_area);
3023 /* If this isn't going to be placed on both the stack and in registers,
3024 set up the register and number of words. */
3025 if (! arg->pass_on_stack)
3026 reg = arg->reg, partial = arg->partial;
3028 if (reg != 0 && partial == 0)
3029 /* Being passed entirely in a register. We shouldn't be called in
3033 /* If this arg needs special alignment, don't load the registers
3035 if (arg->n_aligned_regs != 0)
3038 /* If this is being partially passed in a register, but multiple locations
3039 are specified, we assume that the one partially used is the one that is
3041 if (reg && GET_CODE (reg) == EXPR_LIST)
3042 reg = XEXP (reg, 0);
3044 /* If this is being passed partially in a register, we can't evaluate
3045 it directly into its stack slot. Otherwise, we can. */
3046 if (arg->value == 0)
3048 #ifdef ACCUMULATE_OUTGOING_ARGS
3049 /* stack_arg_under_construction is nonzero if a function argument is
3050 being evaluated directly into the outgoing argument list and
3051 expand_call must take special action to preserve the argument list
3052 if it is called recursively.
3054 For scalar function arguments stack_usage_map is sufficient to
3055 determine which stack slots must be saved and restored. Scalar
3056 arguments in general have pass_on_stack == 0.
3058 If this argument is initialized by a function which takes the
3059 address of the argument (a C++ constructor or a C function
3060 returning a BLKmode structure), then stack_usage_map is
3061 insufficient and expand_call must push the stack around the
3062 function call. Such arguments have pass_on_stack == 1.
3064 Note that it is always safe to set stack_arg_under_construction,
3065 but this generates suboptimal code if set when not needed. */
3067 if (arg->pass_on_stack)
3068 stack_arg_under_construction++;
3070 arg->value = expand_expr (pval,
3072 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
3073 ? NULL_RTX : arg->stack,
3076 /* If we are promoting object (or for any other reason) the mode
3077 doesn't agree, convert the mode. */
3079 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
3080 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
3081 arg->value, arg->unsignedp);
3083 #ifdef ACCUMULATE_OUTGOING_ARGS
3084 if (arg->pass_on_stack)
3085 stack_arg_under_construction--;
3089 /* Don't allow anything left on stack from computation
3090 of argument to alloca. */
3092 do_pending_stack_adjust ();
3094 if (arg->value == arg->stack)
3095 /* If the value is already in the stack slot, we are done. */
3097 else if (arg->mode != BLKmode)
3101 /* Argument is a scalar, not entirely passed in registers.
3102 (If part is passed in registers, arg->partial says how much
3103 and emit_push_insn will take care of putting it there.)
3105 Push it, and if its size is less than the
3106 amount of space allocated to it,
3107 also bump stack pointer by the additional space.
3108 Note that in C the default argument promotions
3109 will prevent such mismatches. */
3111 size = GET_MODE_SIZE (arg->mode);
3112 /* Compute how much space the push instruction will push.
3113 On many machines, pushing a byte will advance the stack
3114 pointer by a halfword. */
3115 #ifdef PUSH_ROUNDING
3116 size = PUSH_ROUNDING (size);
3120 /* Compute how much space the argument should get:
3121 round up to a multiple of the alignment for arguments. */
3122 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
3123 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
3124 / (PARM_BOUNDARY / BITS_PER_UNIT))
3125 * (PARM_BOUNDARY / BITS_PER_UNIT));
3127 /* This isn't already where we want it on the stack, so put it there.
3128 This can either be done with push or copy insns. */
3129 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
3130 0, partial, reg, used - size,
3131 argblock, ARGS_SIZE_RTX (arg->offset));
3135 /* BLKmode, at least partly to be pushed. */
3137 register int excess;
3140 /* Pushing a nonscalar.
3141 If part is passed in registers, PARTIAL says how much
3142 and emit_push_insn will take care of putting it there. */
3144 /* Round its size up to a multiple
3145 of the allocation unit for arguments. */
3147 if (arg->size.var != 0)
3150 size_rtx = ARGS_SIZE_RTX (arg->size);
3154 /* PUSH_ROUNDING has no effect on us, because
3155 emit_push_insn for BLKmode is careful to avoid it. */
3156 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
3157 + partial * UNITS_PER_WORD);
3158 size_rtx = expr_size (pval);
3161 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
3162 TYPE_ALIGN (TREE_TYPE (pval)) / BITS_PER_UNIT, partial,
3163 reg, excess, argblock, ARGS_SIZE_RTX (arg->offset));
3167 /* Unless this is a partially-in-register argument, the argument is now
3170 ??? Note that this can change arg->value from arg->stack to
3171 arg->stack_slot and it matters when they are not the same.
3172 It isn't totally clear that this is correct in all cases. */
3174 arg->value = arg->stack_slot;
3176 /* Once we have pushed something, pops can't safely
3177 be deferred during the rest of the arguments. */
3180 /* ANSI doesn't require a sequence point here,
3181 but PCC has one, so this will avoid some problems. */
3184 /* Free any temporary slots made in processing this argument. Show
3185 that we might have taken the address of something and pushed that
3187 preserve_temp_slots (NULL_RTX);
3191 #ifdef ACCUMULATE_OUTGOING_ARGS
3192 /* Now mark the segment we just used. */
3193 if (argblock && ! variable_size && arg->stack)
3194 for (i = lower_bound; i < upper_bound; i++)
3195 stack_usage_map[i] = 1;