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. */
536 /* Nonzero if we must avoid push-insns in the args for this call.
537 If stack space is allocated for register parameters, but not by the
538 caller, then it is preallocated in the fixed part of the stack frame.
539 So the entire argument block must then be preallocated (i.e., we
540 ignore PUSH_ROUNDING in that case). */
542 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
543 int must_preallocate = 1;
546 int must_preallocate = 0;
548 int must_preallocate = 1;
552 /* Size of the stack reserved for parameter registers. */
553 int reg_parm_stack_space = 0;
555 /* 1 if scanning parms front to back, -1 if scanning back to front. */
557 /* Address of space preallocated for stack parms
558 (on machines that lack push insns), or 0 if space not preallocated. */
561 /* Nonzero if it is plausible that this is a call to alloca. */
563 /* Nonzero if this is a call to setjmp or a related function. */
565 /* Nonzero if this is a call to `longjmp'. */
567 /* Nonzero if this is a call to an inline function. */
568 int is_integrable = 0;
569 /* Nonzero if this is a call to a `const' function.
570 Note that only explicitly named functions are handled as `const' here. */
572 /* Nonzero if this is a call to a `volatile' function. */
574 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
575 /* Define the boundary of the register parm stack space that needs to be
577 int low_to_save = -1, high_to_save;
578 rtx save_area = 0; /* Place that it is saved */
581 #ifdef ACCUMULATE_OUTGOING_ARGS
582 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
583 char *initial_stack_usage_map = stack_usage_map;
586 rtx old_stack_level = 0;
587 int old_pending_adj = 0;
588 int old_stack_arg_under_construction;
589 int old_inhibit_defer_pop = inhibit_defer_pop;
590 tree old_cleanups = cleanups_this_call;
595 /* See if we can find a DECL-node for the actual function.
596 As a result, decide whether this is a call to an integrable function. */
598 p = TREE_OPERAND (exp, 0);
599 if (TREE_CODE (p) == ADDR_EXPR)
601 fndecl = TREE_OPERAND (p, 0);
602 if (TREE_CODE (fndecl) != FUNCTION_DECL)
607 && fndecl != current_function_decl
608 && DECL_INLINE (fndecl)
609 && DECL_SAVED_INSNS (fndecl)
610 && RTX_INTEGRATED_P (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 = before_call ? NEXT_INSN (before_call) : get_insns ();
745 /* Look for a call in the inline function code.
746 If OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl)) is
747 nonzero then there is a call and it is not necessary
748 to scan the insns. */
750 if (OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl)) == 0)
751 for (; insn; insn = NEXT_INSN (insn))
752 if (GET_CODE (insn) == CALL_INSN)
757 /* Reserve enough stack space so that the largest
758 argument list of any function call in the inline
759 function does not overlap the argument list being
760 evaluated. This is usually an overestimate because
761 allocate_dynamic_stack_space reserves space for an
762 outgoing argument list in addition to the requested
763 space, but there is no way to ask for stack space such
764 that an argument list of a certain length can be
765 safely constructed. */
767 int adjust = OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl));
768 #ifdef REG_PARM_STACK_SPACE
769 /* Add the stack space reserved for register arguments
770 in the inline function. What is really needed is the
771 largest value of reg_parm_stack_space in the inline
772 function, but that is not available. Using the current
773 value of reg_parm_stack_space is wrong, but gives
774 correct results on all supported machines. */
775 adjust += reg_parm_stack_space;
778 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
779 allocate_dynamic_stack_space (GEN_INT (adjust),
780 NULL_RTX, BITS_PER_UNIT);
783 emit_insns_before (seq, NEXT_INSN (before_call));
784 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
789 /* If the result is equivalent to TARGET, return TARGET to simplify
790 checks in store_expr. They can be equivalent but not equal in the
791 case of a function that returns BLKmode. */
792 if (temp != target && rtx_equal_p (temp, target))
797 /* If inlining failed, mark FNDECL as needing to be compiled
798 separately after all. If function was declared inline,
800 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
801 && optimize > 0 && ! TREE_ADDRESSABLE (fndecl))
803 warning_with_decl (fndecl, "inlining failed in call to `%s'");
804 warning ("called from here");
806 mark_addressable (fndecl);
809 /* When calling a const function, we must pop the stack args right away,
810 so that the pop is deleted or moved with the call. */
814 function_call_count++;
816 if (fndecl && DECL_NAME (fndecl))
817 name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
820 /* Unless it's a call to a specific function that isn't alloca,
821 if it has one argument, we must assume it might be alloca. */
824 (!(fndecl != 0 && strcmp (name, "alloca"))
826 && TREE_CHAIN (actparms) == 0);
828 /* We assume that alloca will always be called by name. It
829 makes no sense to pass it as a pointer-to-function to
830 anything that does not understand its behavior. */
832 (name && ((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
834 && ! strcmp (name, "alloca"))
835 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
837 && ! strcmp (name, "__builtin_alloca"))));
840 /* See if this is a call to a function that can return more than once
841 or a call to longjmp. */
846 if (name != 0 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 15)
850 /* Disregard prefix _, __ or __x. */
853 if (name[1] == '_' && name[2] == 'x')
855 else if (name[1] == '_')
865 && (! strcmp (tname, "setjmp")
866 || ! strcmp (tname, "setjmp_syscall")))
868 && ! strcmp (tname, "sigsetjmp"))
870 && ! strcmp (tname, "savectx")));
872 && ! strcmp (tname, "siglongjmp"))
875 else if ((tname[0] == 'q' && tname[1] == 's'
876 && ! strcmp (tname, "qsetjmp"))
877 || (tname[0] == 'v' && tname[1] == 'f'
878 && ! strcmp (tname, "vfork")))
881 else if (tname[0] == 'l' && tname[1] == 'o'
882 && ! strcmp (tname, "longjmp"))
887 current_function_calls_alloca = 1;
889 /* Don't let pending stack adjusts add up to too much.
890 Also, do all pending adjustments now
891 if there is any chance this might be a call to alloca. */
893 if (pending_stack_adjust >= 32
894 || (pending_stack_adjust > 0 && may_be_alloca))
895 do_pending_stack_adjust ();
897 /* Operand 0 is a pointer-to-function; get the type of the function. */
898 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
899 if (TREE_CODE (funtype) != POINTER_TYPE)
901 funtype = TREE_TYPE (funtype);
903 /* Push the temporary stack slot level so that we can free any temporaries
907 /* Start updating where the next arg would go.
909 On some machines (such as the PA) indirect calls have a different
910 calling convention than normal calls. The last argument in
911 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
913 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
915 /* If struct_value_rtx is 0, it means pass the address
916 as if it were an extra parameter. */
917 if (structure_value_addr && struct_value_rtx == 0)
919 /* If structure_value_addr is a REG other than
920 virtual_outgoing_args_rtx, we can use always use it. If it
921 is not a REG, we must always copy it into a register.
922 If it is virtual_outgoing_args_rtx, we must copy it to another
923 register in some cases. */
924 rtx temp = (GET_CODE (structure_value_addr) != REG
925 #ifdef ACCUMULATE_OUTGOING_ARGS
926 || (stack_arg_under_construction
927 && structure_value_addr == virtual_outgoing_args_rtx)
929 ? copy_addr_to_reg (structure_value_addr)
930 : structure_value_addr);
933 = tree_cons (error_mark_node,
934 make_tree (build_pointer_type (TREE_TYPE (funtype)),
937 structure_value_addr_parm = 1;
940 /* Count the arguments and set NUM_ACTUALS. */
941 for (p = actparms, i = 0; p; p = TREE_CHAIN (p)) i++;
944 /* Compute number of named args.
945 Normally, don't include the last named arg if anonymous args follow.
946 We do include the last named arg if STRICT_ARGUMENT_NAMING is defined.
947 (If no anonymous args follow, the result of list_length is actually
948 one too large. This is harmless.)
950 If SETUP_INCOMING_VARARGS is defined and STRICT_ARGUMENT_NAMING is not,
951 this machine will be able to place unnamed args that were passed in
952 registers into the stack. So treat all args as named. This allows the
953 insns emitting for a specific argument list to be independent of the
954 function declaration.
956 If SETUP_INCOMING_VARARGS is not defined, we do not have any reliable
957 way to pass unnamed args in registers, so we must force them into
959 #if !defined(SETUP_INCOMING_VARARGS) || defined(STRICT_ARGUMENT_NAMING)
960 if (TYPE_ARG_TYPES (funtype) != 0)
962 = (list_length (TYPE_ARG_TYPES (funtype))
963 #ifndef STRICT_ARGUMENT_NAMING
964 /* Don't include the last named arg. */
967 /* Count the struct value address, if it is passed as a parm. */
968 + structure_value_addr_parm);
971 /* If we know nothing, treat all args as named. */
972 n_named_args = num_actuals;
974 /* Make a vector to hold all the information about each arg. */
975 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
976 bzero ((char *) args, num_actuals * sizeof (struct arg_data));
978 args_size.constant = 0;
981 /* In this loop, we consider args in the order they are written.
982 We fill up ARGS from the front or from the back if necessary
983 so that in any case the first arg to be pushed ends up at the front. */
985 #ifdef PUSH_ARGS_REVERSED
986 i = num_actuals - 1, inc = -1;
987 /* In this case, must reverse order of args
988 so that we compute and push the last arg first. */
993 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
994 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
996 tree type = TREE_TYPE (TREE_VALUE (p));
998 enum machine_mode mode;
1000 args[i].tree_value = TREE_VALUE (p);
1002 /* Replace erroneous argument with constant zero. */
1003 if (type == error_mark_node || TYPE_SIZE (type) == 0)
1004 args[i].tree_value = integer_zero_node, type = integer_type_node;
1006 /* If TYPE is a transparent union, pass things the way we would
1007 pass the first field of the union. We have already verified that
1008 the modes are the same. */
1009 if (TYPE_TRANSPARENT_UNION (type))
1010 type = TREE_TYPE (TYPE_FIELDS (type));
1012 /* Decide where to pass this arg.
1014 args[i].reg is nonzero if all or part is passed in registers.
1016 args[i].partial is nonzero if part but not all is passed in registers,
1017 and the exact value says how many words are passed in registers.
1019 args[i].pass_on_stack is nonzero if the argument must at least be
1020 computed on the stack. It may then be loaded back into registers
1021 if args[i].reg is nonzero.
1023 These decisions are driven by the FUNCTION_... macros and must agree
1024 with those made by function.c. */
1026 /* See if this argument should be passed by invisible reference. */
1027 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1028 && contains_placeholder_p (TYPE_SIZE (type)))
1029 || TREE_ADDRESSABLE (type)
1030 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1031 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, TYPE_MODE (type),
1032 type, argpos < n_named_args)
1036 #ifdef FUNCTION_ARG_CALLEE_COPIES
1037 if (FUNCTION_ARG_CALLEE_COPIES (args_so_far, TYPE_MODE (type), type,
1038 argpos < n_named_args)
1039 /* If it's in a register, we must make a copy of it too. */
1040 /* ??? Is this a sufficient test? Is there a better one? */
1041 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1042 && REG_P (DECL_RTL (args[i].tree_value)))
1043 && ! TREE_ADDRESSABLE (type))
1045 args[i].tree_value = build1 (ADDR_EXPR,
1046 build_pointer_type (type),
1047 args[i].tree_value);
1048 type = build_pointer_type (type);
1053 /* We make a copy of the object and pass the address to the
1054 function being called. */
1057 if (TYPE_SIZE (type) == 0
1058 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
1060 /* This is a variable-sized object. Make space on the stack
1062 rtx size_rtx = expr_size (TREE_VALUE (p));
1064 if (old_stack_level == 0)
1066 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1067 old_pending_adj = pending_stack_adjust;
1068 pending_stack_adjust = 0;
1071 copy = gen_rtx (MEM, BLKmode,
1072 allocate_dynamic_stack_space (size_rtx,
1074 TYPE_ALIGN (type)));
1078 int size = int_size_in_bytes (type);
1079 copy = assign_stack_temp (TYPE_MODE (type), size, 0);
1082 MEM_IN_STRUCT_P (copy) = AGGREGATE_TYPE_P (type);
1084 store_expr (args[i].tree_value, copy, 0);
1087 args[i].tree_value = build1 (ADDR_EXPR,
1088 build_pointer_type (type),
1089 make_tree (type, copy));
1090 type = build_pointer_type (type);
1094 mode = TYPE_MODE (type);
1095 unsignedp = TREE_UNSIGNED (type);
1097 #ifdef PROMOTE_FUNCTION_ARGS
1098 mode = promote_mode (type, mode, &unsignedp, 1);
1101 args[i].unsignedp = unsignedp;
1102 args[i].mode = mode;
1103 args[i].reg = FUNCTION_ARG (args_so_far, mode, type,
1104 argpos < n_named_args);
1105 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1108 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, type,
1109 argpos < n_named_args);
1112 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1114 /* If FUNCTION_ARG returned an (expr_list (nil) FOO), it means that
1115 we are to pass this arg in the register(s) designated by FOO, but
1116 also to pass it in the stack. */
1117 if (args[i].reg && GET_CODE (args[i].reg) == EXPR_LIST
1118 && XEXP (args[i].reg, 0) == 0)
1119 args[i].pass_on_stack = 1, args[i].reg = XEXP (args[i].reg, 1);
1121 /* If this is an addressable type, we must preallocate the stack
1122 since we must evaluate the object into its final location.
1124 If this is to be passed in both registers and the stack, it is simpler
1126 if (TREE_ADDRESSABLE (type)
1127 || (args[i].pass_on_stack && args[i].reg != 0))
1128 must_preallocate = 1;
1130 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1131 we cannot consider this function call constant. */
1132 if (TREE_ADDRESSABLE (type))
1135 /* Compute the stack-size of this argument. */
1136 if (args[i].reg == 0 || args[i].partial != 0
1137 #ifdef REG_PARM_STACK_SPACE
1138 || reg_parm_stack_space > 0
1140 || args[i].pass_on_stack)
1141 locate_and_pad_parm (mode, type,
1142 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1147 fndecl, &args_size, &args[i].offset,
1150 #ifndef ARGS_GROW_DOWNWARD
1151 args[i].slot_offset = args_size;
1154 #ifndef REG_PARM_STACK_SPACE
1155 /* If a part of the arg was put into registers,
1156 don't include that part in the amount pushed. */
1157 if (! args[i].pass_on_stack)
1158 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1159 / (PARM_BOUNDARY / BITS_PER_UNIT)
1160 * (PARM_BOUNDARY / BITS_PER_UNIT));
1163 /* Update ARGS_SIZE, the total stack space for args so far. */
1165 args_size.constant += args[i].size.constant;
1166 if (args[i].size.var)
1168 ADD_PARM_SIZE (args_size, args[i].size.var);
1171 /* Since the slot offset points to the bottom of the slot,
1172 we must record it after incrementing if the args grow down. */
1173 #ifdef ARGS_GROW_DOWNWARD
1174 args[i].slot_offset = args_size;
1176 args[i].slot_offset.constant = -args_size.constant;
1179 SUB_PARM_SIZE (args[i].slot_offset, args_size.var);
1183 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1184 have been used, etc. */
1186 FUNCTION_ARG_ADVANCE (args_so_far, TYPE_MODE (type), type,
1187 argpos < n_named_args);
1190 #ifdef FINAL_REG_PARM_STACK_SPACE
1191 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
1195 /* Compute the actual size of the argument block required. The variable
1196 and constant sizes must be combined, the size may have to be rounded,
1197 and there may be a minimum required size. */
1199 original_args_size = args_size;
1202 /* If this function requires a variable-sized argument list, don't try to
1203 make a cse'able block for this call. We may be able to do this
1204 eventually, but it is too complicated to keep track of what insns go
1205 in the cse'able block and which don't. */
1208 must_preallocate = 1;
1210 args_size.var = ARGS_SIZE_TREE (args_size);
1211 args_size.constant = 0;
1213 #ifdef STACK_BOUNDARY
1214 if (STACK_BOUNDARY != BITS_PER_UNIT)
1215 args_size.var = round_up (args_size.var, STACK_BYTES);
1218 #ifdef REG_PARM_STACK_SPACE
1219 if (reg_parm_stack_space > 0)
1222 = size_binop (MAX_EXPR, args_size.var,
1223 size_int (REG_PARM_STACK_SPACE (fndecl)));
1225 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1226 /* The area corresponding to register parameters is not to count in
1227 the size of the block we need. So make the adjustment. */
1229 = size_binop (MINUS_EXPR, args_size.var,
1230 size_int (reg_parm_stack_space));
1237 #ifdef STACK_BOUNDARY
1238 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
1239 / STACK_BYTES) * STACK_BYTES);
1242 #ifdef REG_PARM_STACK_SPACE
1243 args_size.constant = MAX (args_size.constant,
1244 reg_parm_stack_space);
1245 #ifdef MAYBE_REG_PARM_STACK_SPACE
1246 if (reg_parm_stack_space == 0)
1247 args_size.constant = 0;
1249 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1250 args_size.constant -= reg_parm_stack_space;
1255 /* See if we have or want to preallocate stack space.
1257 If we would have to push a partially-in-regs parm
1258 before other stack parms, preallocate stack space instead.
1260 If the size of some parm is not a multiple of the required stack
1261 alignment, we must preallocate.
1263 If the total size of arguments that would otherwise create a copy in
1264 a temporary (such as a CALL) is more than half the total argument list
1265 size, preallocation is faster.
1267 Another reason to preallocate is if we have a machine (like the m88k)
1268 where stack alignment is required to be maintained between every
1269 pair of insns, not just when the call is made. However, we assume here
1270 that such machines either do not have push insns (and hence preallocation
1271 would occur anyway) or the problem is taken care of with
1274 if (! must_preallocate)
1276 int partial_seen = 0;
1277 int copy_to_evaluate_size = 0;
1279 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1281 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1283 else if (partial_seen && args[i].reg == 0)
1284 must_preallocate = 1;
1286 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1287 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1288 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1289 || TREE_CODE (args[i].tree_value) == COND_EXPR
1290 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1291 copy_to_evaluate_size
1292 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1295 if (copy_to_evaluate_size * 2 >= args_size.constant
1296 && args_size.constant > 0)
1297 must_preallocate = 1;
1300 /* If the structure value address will reference the stack pointer, we must
1301 stabilize it. We don't need to do this if we know that we are not going
1302 to adjust the stack pointer in processing this call. */
1304 if (structure_value_addr
1305 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
1306 || reg_mentioned_p (virtual_outgoing_args_rtx, structure_value_addr))
1308 #ifndef ACCUMULATE_OUTGOING_ARGS
1309 || args_size.constant
1312 structure_value_addr = copy_to_reg (structure_value_addr);
1314 /* If this function call is cse'able, precompute all the parameters.
1315 Note that if the parameter is constructed into a temporary, this will
1316 cause an additional copy because the parameter will be constructed
1317 into a temporary location and then copied into the outgoing arguments.
1318 If a parameter contains a call to alloca and this function uses the
1319 stack, precompute the parameter. */
1321 /* If we preallocated the stack space, and some arguments must be passed
1322 on the stack, then we must precompute any parameter which contains a
1323 function call which will store arguments on the stack.
1324 Otherwise, evaluating the parameter may clobber previous parameters
1325 which have already been stored into the stack. */
1327 for (i = 0; i < num_actuals; i++)
1329 || ((args_size.var != 0 || args_size.constant != 0)
1330 && calls_function (args[i].tree_value, 1))
1331 || (must_preallocate && (args_size.var != 0 || args_size.constant != 0)
1332 && calls_function (args[i].tree_value, 0)))
1334 /* If this is an addressable type, we cannot pre-evaluate it. */
1335 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1340 args[i].initial_value = args[i].value
1341 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1343 preserve_temp_slots (args[i].value);
1346 /* ANSI doesn't require a sequence point here,
1347 but PCC has one, so this will avoid some problems. */
1350 args[i].initial_value = args[i].value
1351 = protect_from_queue (args[i].initial_value, 0);
1353 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) != args[i].mode)
1355 = convert_modes (args[i].mode,
1356 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1357 args[i].value, args[i].unsignedp);
1360 /* Now we are about to start emitting insns that can be deleted
1361 if a libcall is deleted. */
1365 /* If we have no actual push instructions, or shouldn't use them,
1366 make space for all args right now. */
1368 if (args_size.var != 0)
1370 if (old_stack_level == 0)
1372 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1373 old_pending_adj = pending_stack_adjust;
1374 pending_stack_adjust = 0;
1375 #ifdef ACCUMULATE_OUTGOING_ARGS
1376 /* stack_arg_under_construction says whether a stack arg is
1377 being constructed at the old stack level. Pushing the stack
1378 gets a clean outgoing argument block. */
1379 old_stack_arg_under_construction = stack_arg_under_construction;
1380 stack_arg_under_construction = 0;
1383 argblock = push_block (ARGS_SIZE_RTX (args_size), 0, 0);
1387 /* Note that we must go through the motions of allocating an argument
1388 block even if the size is zero because we may be storing args
1389 in the area reserved for register arguments, which may be part of
1392 int needed = args_size.constant;
1394 /* Store the maximum argument space used. It will be pushed by the
1395 prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow checking). */
1397 if (needed > current_function_outgoing_args_size)
1398 current_function_outgoing_args_size = needed;
1400 if (must_preallocate)
1402 #ifdef ACCUMULATE_OUTGOING_ARGS
1403 /* Since the stack pointer will never be pushed, it is possible for
1404 the evaluation of a parm to clobber something we have already
1405 written to the stack. Since most function calls on RISC machines
1406 do not use the stack, this is uncommon, but must work correctly.
1408 Therefore, we save any area of the stack that was already written
1409 and that we are using. Here we set up to do this by making a new
1410 stack usage map from the old one. The actual save will be done
1413 Another approach might be to try to reorder the argument
1414 evaluations to avoid this conflicting stack usage. */
1416 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1417 /* Since we will be writing into the entire argument area, the
1418 map must be allocated for its entire size, not just the part that
1419 is the responsibility of the caller. */
1420 needed += reg_parm_stack_space;
1423 #ifdef ARGS_GROW_DOWNWARD
1424 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
1427 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
1430 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
1432 if (initial_highest_arg_in_use)
1433 bcopy (initial_stack_usage_map, stack_usage_map,
1434 initial_highest_arg_in_use);
1436 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
1437 bzero (&stack_usage_map[initial_highest_arg_in_use],
1438 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
1441 /* The address of the outgoing argument list must not be copied to a
1442 register here, because argblock would be left pointing to the
1443 wrong place after the call to allocate_dynamic_stack_space below.
1446 argblock = virtual_outgoing_args_rtx;
1448 #else /* not ACCUMULATE_OUTGOING_ARGS */
1449 if (inhibit_defer_pop == 0)
1451 /* Try to reuse some or all of the pending_stack_adjust
1452 to get this space. Maybe we can avoid any pushing. */
1453 if (needed > pending_stack_adjust)
1455 needed -= pending_stack_adjust;
1456 pending_stack_adjust = 0;
1460 pending_stack_adjust -= needed;
1464 /* Special case this because overhead of `push_block' in this
1465 case is non-trivial. */
1467 argblock = virtual_outgoing_args_rtx;
1469 argblock = push_block (GEN_INT (needed), 0, 0);
1471 /* We only really need to call `copy_to_reg' in the case where push
1472 insns are going to be used to pass ARGBLOCK to a function
1473 call in ARGS. In that case, the stack pointer changes value
1474 from the allocation point to the call point, and hence
1475 the value of VIRTUAL_OUTGOING_ARGS_RTX changes as well.
1476 But might as well always do it. */
1477 argblock = copy_to_reg (argblock);
1478 #endif /* not ACCUMULATE_OUTGOING_ARGS */
1482 #ifdef ACCUMULATE_OUTGOING_ARGS
1483 /* The save/restore code in store_one_arg handles all cases except one:
1484 a constructor call (including a C function returning a BLKmode struct)
1485 to initialize an argument. */
1486 if (stack_arg_under_construction)
1488 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1489 rtx push_size = GEN_INT (reg_parm_stack_space + args_size.constant);
1491 rtx push_size = GEN_INT (args_size.constant);
1493 if (old_stack_level == 0)
1495 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1496 old_pending_adj = pending_stack_adjust;
1497 pending_stack_adjust = 0;
1498 /* stack_arg_under_construction says whether a stack arg is
1499 being constructed at the old stack level. Pushing the stack
1500 gets a clean outgoing argument block. */
1501 old_stack_arg_under_construction = stack_arg_under_construction;
1502 stack_arg_under_construction = 0;
1503 /* Make a new map for the new argument list. */
1504 stack_usage_map = (char *)alloca (highest_outgoing_arg_in_use);
1505 bzero (stack_usage_map, highest_outgoing_arg_in_use);
1506 highest_outgoing_arg_in_use = 0;
1508 allocate_dynamic_stack_space (push_size, NULL_RTX, BITS_PER_UNIT);
1510 /* If argument evaluation might modify the stack pointer, copy the
1511 address of the argument list to a register. */
1512 for (i = 0; i < num_actuals; i++)
1513 if (args[i].pass_on_stack)
1515 argblock = copy_addr_to_reg (argblock);
1521 /* If we preallocated stack space, compute the address of each argument.
1522 We need not ensure it is a valid memory address here; it will be
1523 validized when it is used. */
1526 rtx arg_reg = argblock;
1529 if (GET_CODE (argblock) == PLUS)
1530 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1532 for (i = 0; i < num_actuals; i++)
1534 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1535 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1538 /* Skip this parm if it will not be passed on the stack. */
1539 if (! args[i].pass_on_stack && args[i].reg != 0)
1542 if (GET_CODE (offset) == CONST_INT)
1543 addr = plus_constant (arg_reg, INTVAL (offset));
1545 addr = gen_rtx (PLUS, Pmode, arg_reg, offset);
1547 addr = plus_constant (addr, arg_offset);
1548 args[i].stack = gen_rtx (MEM, args[i].mode, addr);
1549 MEM_IN_STRUCT_P (args[i].stack)
1550 = AGGREGATE_TYPE_P (TREE_TYPE (args[i].tree_value));
1552 if (GET_CODE (slot_offset) == CONST_INT)
1553 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1555 addr = gen_rtx (PLUS, Pmode, arg_reg, slot_offset);
1557 addr = plus_constant (addr, arg_offset);
1558 args[i].stack_slot = gen_rtx (MEM, args[i].mode, addr);
1562 #ifdef PUSH_ARGS_REVERSED
1563 #ifdef STACK_BOUNDARY
1564 /* If we push args individually in reverse order, perform stack alignment
1565 before the first push (the last arg). */
1567 anti_adjust_stack (GEN_INT (args_size.constant
1568 - original_args_size.constant));
1572 /* Don't try to defer pops if preallocating, not even from the first arg,
1573 since ARGBLOCK probably refers to the SP. */
1577 /* Get the function to call, in the form of RTL. */
1580 /* If this is the first use of the function, see if we need to
1581 make an external definition for it. */
1582 if (! TREE_USED (fndecl))
1584 assemble_external (fndecl);
1585 TREE_USED (fndecl) = 1;
1588 /* Get a SYMBOL_REF rtx for the function address. */
1589 funexp = XEXP (DECL_RTL (fndecl), 0);
1592 /* Generate an rtx (probably a pseudo-register) for the address. */
1595 funexp = expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1596 pop_temp_slots (); /* FUNEXP can't be BLKmode */
1600 /* Figure out the register where the value, if any, will come back. */
1602 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
1603 && ! structure_value_addr)
1605 if (pcc_struct_value)
1606 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
1609 valreg = hard_function_value (TREE_TYPE (exp), fndecl);
1612 /* Precompute all register parameters. It isn't safe to compute anything
1613 once we have started filling any specific hard regs. */
1615 for (i = 0; i < num_actuals; i++)
1616 if (args[i].reg != 0 && ! args[i].pass_on_stack)
1620 if (args[i].value == 0)
1623 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
1625 preserve_temp_slots (args[i].value);
1628 /* ANSI doesn't require a sequence point here,
1629 but PCC has one, so this will avoid some problems. */
1633 /* If we are to promote the function arg to a wider mode,
1636 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
1638 = convert_modes (args[i].mode,
1639 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1640 args[i].value, args[i].unsignedp);
1642 /* If the value is expensive, and we are inside an appropriately
1643 short loop, put the value into a pseudo and then put the pseudo
1646 For small register classes, also do this if this call uses
1647 register parameters. This is to avoid reload conflicts while
1648 loading the parameters registers. */
1650 if ((! (GET_CODE (args[i].value) == REG
1651 || (GET_CODE (args[i].value) == SUBREG
1652 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
1653 && args[i].mode != BLKmode
1654 && rtx_cost (args[i].value, SET) > 2
1655 #ifdef SMALL_REGISTER_CLASSES
1656 && (reg_parm_seen || preserve_subexpressions_p ())
1658 && preserve_subexpressions_p ()
1661 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
1664 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
1665 /* The argument list is the property of the called routine and it
1666 may clobber it. If the fixed area has been used for previous
1667 parameters, we must save and restore it.
1669 Here we compute the boundary of the that needs to be saved, if any. */
1671 #ifdef ARGS_GROW_DOWNWARD
1672 for (i = 0; i < reg_parm_stack_space + 1; i++)
1674 for (i = 0; i < reg_parm_stack_space; i++)
1677 if (i >= highest_outgoing_arg_in_use
1678 || stack_usage_map[i] == 0)
1681 if (low_to_save == -1)
1687 if (low_to_save >= 0)
1689 int num_to_save = high_to_save - low_to_save + 1;
1690 enum machine_mode save_mode
1691 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
1694 /* If we don't have the required alignment, must do this in BLKmode. */
1695 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
1696 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
1697 save_mode = BLKmode;
1699 stack_area = gen_rtx (MEM, save_mode,
1700 memory_address (save_mode,
1702 #ifdef ARGS_GROW_DOWNWARD
1703 plus_constant (argblock,
1706 plus_constant (argblock,
1710 if (save_mode == BLKmode)
1712 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
1713 MEM_IN_STRUCT_P (save_area) = 0;
1714 emit_block_move (validize_mem (save_area), stack_area,
1715 GEN_INT (num_to_save),
1716 PARM_BOUNDARY / BITS_PER_UNIT);
1720 save_area = gen_reg_rtx (save_mode);
1721 emit_move_insn (save_area, stack_area);
1727 /* Now store (and compute if necessary) all non-register parms.
1728 These come before register parms, since they can require block-moves,
1729 which could clobber the registers used for register parms.
1730 Parms which have partial registers are not stored here,
1731 but we do preallocate space here if they want that. */
1733 for (i = 0; i < num_actuals; i++)
1734 if (args[i].reg == 0 || args[i].pass_on_stack)
1735 store_one_arg (&args[i], argblock, may_be_alloca,
1736 args_size.var != 0, fndecl, reg_parm_stack_space);
1738 /* If we have a parm that is passed in registers but not in memory
1739 and whose alignment does not permit a direct copy into registers,
1740 make a group of pseudos that correspond to each register that we
1743 if (STRICT_ALIGNMENT)
1744 for (i = 0; i < num_actuals; i++)
1745 if (args[i].reg != 0 && ! args[i].pass_on_stack
1746 && args[i].mode == BLKmode
1747 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1748 < MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1750 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1751 int big_endian_correction = 0;
1753 args[i].n_aligned_regs
1754 = args[i].partial ? args[i].partial
1755 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1757 args[i].aligned_regs = (rtx *) alloca (sizeof (rtx)
1758 * args[i].n_aligned_regs);
1760 /* Structures smaller than a word are aligned to the least
1761 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1762 this means we must skip the empty high order bytes when
1763 calculating the bit offset. */
1764 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
1765 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1767 for (j = 0; j < args[i].n_aligned_regs; j++)
1769 rtx reg = gen_reg_rtx (word_mode);
1770 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1771 int bitsize = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
1774 args[i].aligned_regs[j] = reg;
1776 /* Clobber REG and move each partword into it. Ensure we don't
1777 go past the end of the structure. Note that the loop below
1778 works because we've already verified that padding
1779 and endianness are compatible. */
1781 emit_insn (gen_rtx (CLOBBER, VOIDmode, reg));
1784 bitpos < BITS_PER_WORD && bytes > 0;
1785 bitpos += bitsize, bytes -= bitsize / BITS_PER_UNIT)
1787 int xbitpos = bitpos + big_endian_correction;
1789 store_bit_field (reg, bitsize, xbitpos, word_mode,
1790 extract_bit_field (word, bitsize, bitpos, 1,
1791 NULL_RTX, word_mode,
1793 bitsize / BITS_PER_UNIT,
1795 bitsize / BITS_PER_UNIT, BITS_PER_WORD);
1800 /* Now store any partially-in-registers parm.
1801 This is the last place a block-move can happen. */
1803 for (i = 0; i < num_actuals; i++)
1804 if (args[i].partial != 0 && ! args[i].pass_on_stack)
1805 store_one_arg (&args[i], argblock, may_be_alloca,
1806 args_size.var != 0, fndecl, reg_parm_stack_space);
1808 #ifndef PUSH_ARGS_REVERSED
1809 #ifdef STACK_BOUNDARY
1810 /* If we pushed args in forward order, perform stack alignment
1811 after pushing the last arg. */
1813 anti_adjust_stack (GEN_INT (args_size.constant
1814 - original_args_size.constant));
1818 /* If register arguments require space on the stack and stack space
1819 was not preallocated, allocate stack space here for arguments
1820 passed in registers. */
1821 #if ! defined(ACCUMULATE_OUTGOING_ARGS) && defined(OUTGOING_REG_PARM_STACK_SPACE)
1822 if (must_preallocate == 0 && reg_parm_stack_space > 0)
1823 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
1826 /* Pass the function the address in which to return a structure value. */
1827 if (structure_value_addr && ! structure_value_addr_parm)
1829 emit_move_insn (struct_value_rtx,
1831 force_operand (structure_value_addr,
1833 if (GET_CODE (struct_value_rtx) == REG)
1834 use_reg (&call_fusage, struct_value_rtx);
1837 funexp = prepare_call_address (funexp, fndecl, &call_fusage, reg_parm_seen);
1839 /* Now do the register loads required for any wholly-register parms or any
1840 parms which are passed both on the stack and in a register. Their
1841 expressions were already evaluated.
1843 Mark all register-parms as living through the call, putting these USE
1844 insns in the CALL_INSN_FUNCTION_USAGE field. */
1846 for (i = 0; i < num_actuals; i++)
1848 rtx list = args[i].reg;
1849 int partial = args[i].partial;
1856 /* Process each register that needs to get this arg. */
1857 if (GET_CODE (list) == EXPR_LIST)
1858 reg = XEXP (list, 0), list = XEXP (list, 1);
1860 reg = list, list = 0;
1862 /* Set to non-negative if must move a word at a time, even if just
1863 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1864 we just use a normal move insn. This value can be zero if the
1865 argument is a zero size structure with no fields. */
1866 nregs = (partial ? partial
1867 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1868 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1869 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1872 /* If simple case, just do move. If normal partial, store_one_arg
1873 has already loaded the register for us. In all other cases,
1874 load the register(s) from memory. */
1877 emit_move_insn (reg, args[i].value);
1879 /* If we have pre-computed the values to put in the registers in
1880 the case of non-aligned structures, copy them in now. */
1882 else if (args[i].n_aligned_regs != 0)
1883 for (j = 0; j < args[i].n_aligned_regs; j++)
1884 emit_move_insn (gen_rtx (REG, word_mode, REGNO (reg) + j),
1885 args[i].aligned_regs[j]);
1887 else if (args[i].partial == 0 || args[i].pass_on_stack)
1888 move_block_to_reg (REGNO (reg),
1889 validize_mem (args[i].value), nregs,
1893 use_reg (&call_fusage, reg);
1895 use_regs (&call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1897 /* PARTIAL referred only to the first register, so clear it for the
1903 /* Perform postincrements before actually calling the function. */
1906 /* All arguments and registers used for the call must be set up by now! */
1908 /* Generate the actual call instruction. */
1909 emit_call_1 (funexp, fndecl, funtype, args_size.constant, struct_value_size,
1910 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
1911 valreg, old_inhibit_defer_pop, call_fusage, is_const);
1913 /* If call is cse'able, make appropriate pair of reg-notes around it.
1914 Test valreg so we don't crash; may safely ignore `const'
1915 if return type is void. */
1916 if (is_const && valreg != 0)
1919 rtx temp = gen_reg_rtx (GET_MODE (valreg));
1922 /* Construct an "equal form" for the value which mentions all the
1923 arguments in order as well as the function name. */
1924 #ifdef PUSH_ARGS_REVERSED
1925 for (i = 0; i < num_actuals; i++)
1926 note = gen_rtx (EXPR_LIST, VOIDmode, args[i].initial_value, note);
1928 for (i = num_actuals - 1; i >= 0; i--)
1929 note = gen_rtx (EXPR_LIST, VOIDmode, args[i].initial_value, note);
1931 note = gen_rtx (EXPR_LIST, VOIDmode, funexp, note);
1933 insns = get_insns ();
1936 emit_libcall_block (insns, temp, valreg, note);
1942 /* Otherwise, just write out the sequence without a note. */
1943 rtx insns = get_insns ();
1949 /* For calls to `setjmp', etc., inform flow.c it should complain
1950 if nonvolatile values are live. */
1954 emit_note (name, NOTE_INSN_SETJMP);
1955 current_function_calls_setjmp = 1;
1959 current_function_calls_longjmp = 1;
1961 /* Notice functions that cannot return.
1962 If optimizing, insns emitted below will be dead.
1963 If not optimizing, they will exist, which is useful
1964 if the user uses the `return' command in the debugger. */
1966 if (is_volatile || is_longjmp)
1969 /* If value type not void, return an rtx for the value. */
1971 /* If there are cleanups to be called, don't use a hard reg as target. */
1972 if (cleanups_this_call != old_cleanups
1973 && target && REG_P (target)
1974 && REGNO (target) < FIRST_PSEUDO_REGISTER)
1977 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
1980 target = const0_rtx;
1982 else if (structure_value_addr)
1984 if (target == 0 || GET_CODE (target) != MEM)
1986 target = gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)),
1987 memory_address (TYPE_MODE (TREE_TYPE (exp)),
1988 structure_value_addr));
1989 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
1992 else if (pcc_struct_value)
1996 /* We used leave the value in the location that it is
1997 returned in, but that causes problems if it is used more
1998 than once in one expression. Rather than trying to track
1999 when a copy is required, we always copy when TARGET is
2000 not specified. This calling sequence is only used on
2001 a few machines and TARGET is usually nonzero. */
2002 if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
2004 target = assign_stack_temp (BLKmode,
2005 int_size_in_bytes (TREE_TYPE (exp)),
2008 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
2010 /* Save this temp slot around the pop below. */
2011 preserve_temp_slots (target);
2014 target = gen_reg_rtx (TYPE_MODE (TREE_TYPE (exp)));
2017 if (TYPE_MODE (TREE_TYPE (exp)) != BLKmode)
2018 emit_move_insn (target, gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)),
2019 copy_to_reg (valreg)));
2021 emit_block_move (target, gen_rtx (MEM, BLKmode, copy_to_reg (valreg)),
2023 TYPE_ALIGN (TREE_TYPE (exp)) / BITS_PER_UNIT);
2025 else if (target && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
2026 && GET_MODE (target) == GET_MODE (valreg))
2027 /* TARGET and VALREG cannot be equal at this point because the latter
2028 would not have REG_FUNCTION_VALUE_P true, while the former would if
2029 it were referring to the same register.
2031 If they refer to the same register, this move will be a no-op, except
2032 when function inlining is being done. */
2033 emit_move_insn (target, valreg);
2034 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
2036 /* Some machines (the PA for example) want to return all small
2037 structures in registers regardless of the structure's alignment.
2039 Deal with them explicitly by copying from the return registers
2040 into the target MEM locations. */
2041 int bytes = int_size_in_bytes (TREE_TYPE (exp));
2042 int n_regs = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
2044 enum machine_mode tmpmode;
2046 int bitsize = MIN (TYPE_ALIGN (TREE_TYPE (exp)), BITS_PER_WORD);
2047 int bitpos, xbitpos, big_endian_correction = 0;
2051 target = assign_stack_temp (BLKmode, bytes, 0);
2052 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
2053 preserve_temp_slots (target);
2056 /* This code assumes valreg is at least a full word. If it isn't,
2057 copy it into a new pseudo which is a full word. */
2058 if (GET_MODE (valreg) != BLKmode
2059 && GET_MODE_SIZE (GET_MODE (valreg)) < UNITS_PER_WORD)
2060 valreg = convert_to_mode (word_mode, valreg,
2061 TREE_UNSIGNED (TREE_TYPE (exp)));
2063 /* Structures whose size is not a multiple of a word are aligned
2064 to the least significant byte (to the right). On a BYTES_BIG_ENDIAN
2065 machine, this means we must skip the empty high order bytes when
2066 calculating the bit offset. */
2067 if (BYTES_BIG_ENDIAN && bytes % UNITS_PER_WORD)
2068 big_endian_correction = (BITS_PER_WORD - ((bytes % UNITS_PER_WORD)
2071 /* Copy the structure BITSIZE bites at a time.
2073 We could probably emit more efficient code for machines
2074 which do not use strict alignment, but it doesn't seem
2075 worth the effort at the current time. */
2076 for (bitpos = 0, xbitpos = big_endian_correction;
2077 bitpos < bytes * BITS_PER_UNIT;
2078 bitpos += bitsize, xbitpos += bitsize)
2081 /* We need a new source operand each time xbitpos is on a
2082 word boundary and when xbitpos == big_endian_correction
2083 (the first time through). */
2084 if (xbitpos % BITS_PER_WORD == 0
2085 || xbitpos == big_endian_correction)
2086 src = operand_subword_force (valreg,
2087 xbitpos / BITS_PER_WORD,
2090 /* We need a new destination operand each time bitpos is on
2092 if (bitpos % BITS_PER_WORD == 0)
2093 dst = operand_subword (target, bitpos / BITS_PER_WORD, 1, BLKmode);
2095 /* Use xbitpos for the source extraction (right justified) and
2096 xbitpos for the destination store (left justified). */
2097 store_bit_field (dst, bitsize, bitpos % BITS_PER_WORD, word_mode,
2098 extract_bit_field (src, bitsize,
2099 xbitpos % BITS_PER_WORD, 1,
2100 NULL_RTX, word_mode,
2102 bitsize / BITS_PER_UNIT,
2104 bitsize / BITS_PER_UNIT, BITS_PER_WORD);
2108 target = copy_to_reg (valreg);
2110 #ifdef PROMOTE_FUNCTION_RETURN
2111 /* If we promoted this return value, make the proper SUBREG. TARGET
2112 might be const0_rtx here, so be careful. */
2113 if (GET_CODE (target) == REG
2114 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
2115 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
2117 tree type = TREE_TYPE (exp);
2118 int unsignedp = TREE_UNSIGNED (type);
2120 /* If we don't promote as expected, something is wrong. */
2121 if (GET_MODE (target)
2122 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
2125 target = gen_rtx (SUBREG, TYPE_MODE (type), target, 0);
2126 SUBREG_PROMOTED_VAR_P (target) = 1;
2127 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
2131 if (flag_short_temps)
2133 /* Perform all cleanups needed for the arguments of this call
2134 (i.e. destructors in C++). */
2135 expand_cleanups_to (old_cleanups);
2138 /* If size of args is variable or this was a constructor call for a stack
2139 argument, restore saved stack-pointer value. */
2141 if (old_stack_level)
2143 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
2144 pending_stack_adjust = old_pending_adj;
2145 #ifdef ACCUMULATE_OUTGOING_ARGS
2146 stack_arg_under_construction = old_stack_arg_under_construction;
2147 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2148 stack_usage_map = initial_stack_usage_map;
2151 #ifdef ACCUMULATE_OUTGOING_ARGS
2154 #ifdef REG_PARM_STACK_SPACE
2157 enum machine_mode save_mode = GET_MODE (save_area);
2159 = gen_rtx (MEM, save_mode,
2160 memory_address (save_mode,
2161 #ifdef ARGS_GROW_DOWNWARD
2162 plus_constant (argblock, - high_to_save)
2164 plus_constant (argblock, low_to_save)
2168 if (save_mode != BLKmode)
2169 emit_move_insn (stack_area, save_area);
2171 emit_block_move (stack_area, validize_mem (save_area),
2172 GEN_INT (high_to_save - low_to_save + 1),
2173 PARM_BOUNDARY / BITS_PER_UNIT);
2177 /* If we saved any argument areas, restore them. */
2178 for (i = 0; i < num_actuals; i++)
2179 if (args[i].save_area)
2181 enum machine_mode save_mode = GET_MODE (args[i].save_area);
2183 = gen_rtx (MEM, save_mode,
2184 memory_address (save_mode,
2185 XEXP (args[i].stack_slot, 0)));
2187 if (save_mode != BLKmode)
2188 emit_move_insn (stack_area, args[i].save_area);
2190 emit_block_move (stack_area, validize_mem (args[i].save_area),
2191 GEN_INT (args[i].size.constant),
2192 PARM_BOUNDARY / BITS_PER_UNIT);
2195 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2196 stack_usage_map = initial_stack_usage_map;
2200 /* If this was alloca, record the new stack level for nonlocal gotos.
2201 Check for the handler slots since we might not have a save area
2202 for non-local gotos. */
2204 if (may_be_alloca && nonlocal_goto_handler_slot != 0)
2205 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
2212 /* Output a library call to function FUN (a SYMBOL_REF rtx)
2213 (emitting the queue unless NO_QUEUE is nonzero),
2214 for a value of mode OUTMODE,
2215 with NARGS different arguments, passed as alternating rtx values
2216 and machine_modes to convert them to.
2217 The rtx values should have been passed through protect_from_queue already.
2219 NO_QUEUE will be true if and only if the library call is a `const' call
2220 which will be enclosed in REG_LIBCALL/REG_RETVAL notes; it is equivalent
2221 to the variable is_const in expand_call.
2223 NO_QUEUE must be true for const calls, because if it isn't, then
2224 any pending increment will be emitted between REG_LIBCALL/REG_RETVAL notes,
2225 and will be lost if the libcall sequence is optimized away.
2227 NO_QUEUE must be false for non-const calls, because if it isn't, the
2228 call insn will have its CONST_CALL_P bit set, and it will be incorrectly
2229 optimized. For instance, the instruction scheduler may incorrectly
2230 move memory references across the non-const call. */
2233 emit_library_call VPROTO((rtx orgfun, int no_queue, enum machine_mode outmode,
2239 enum machine_mode outmode;
2243 /* Total size in bytes of all the stack-parms scanned so far. */
2244 struct args_size args_size;
2245 /* Size of arguments before any adjustments (such as rounding). */
2246 struct args_size original_args_size;
2247 register int argnum;
2252 CUMULATIVE_ARGS args_so_far;
2253 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2254 struct args_size offset; struct args_size size; };
2256 int old_inhibit_defer_pop = inhibit_defer_pop;
2257 rtx call_fusage = 0;
2259 VA_START (p, nargs);
2262 orgfun = va_arg (p, rtx);
2263 no_queue = va_arg (p, int);
2264 outmode = va_arg (p, enum machine_mode);
2265 nargs = va_arg (p, int);
2270 /* Copy all the libcall-arguments out of the varargs data
2271 and into a vector ARGVEC.
2273 Compute how to pass each argument. We only support a very small subset
2274 of the full argument passing conventions to limit complexity here since
2275 library functions shouldn't have many args. */
2277 argvec = (struct arg *) alloca (nargs * sizeof (struct arg));
2279 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
2281 args_size.constant = 0;
2286 for (count = 0; count < nargs; count++)
2288 rtx val = va_arg (p, rtx);
2289 enum machine_mode mode = va_arg (p, enum machine_mode);
2291 /* We cannot convert the arg value to the mode the library wants here;
2292 must do it earlier where we know the signedness of the arg. */
2294 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2297 /* On some machines, there's no way to pass a float to a library fcn.
2298 Pass it as a double instead. */
2299 #ifdef LIBGCC_NEEDS_DOUBLE
2300 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2301 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
2304 /* There's no need to call protect_from_queue, because
2305 either emit_move_insn or emit_push_insn will do that. */
2307 /* Make sure it is a reasonable operand for a move or push insn. */
2308 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2309 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2310 val = force_operand (val, NULL_RTX);
2312 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2313 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2315 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2316 be viewed as just an efficiency improvement. */
2317 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2318 emit_move_insn (slot, val);
2319 val = force_operand (XEXP (slot, 0), NULL_RTX);
2324 argvec[count].value = val;
2325 argvec[count].mode = mode;
2327 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2328 if (argvec[count].reg && GET_CODE (argvec[count].reg) == EXPR_LIST)
2330 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2331 argvec[count].partial
2332 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2334 argvec[count].partial = 0;
2337 locate_and_pad_parm (mode, NULL_TREE,
2338 argvec[count].reg && argvec[count].partial == 0,
2339 NULL_TREE, &args_size, &argvec[count].offset,
2340 &argvec[count].size);
2342 if (argvec[count].size.var)
2345 #ifndef REG_PARM_STACK_SPACE
2346 if (argvec[count].partial)
2347 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2350 if (argvec[count].reg == 0 || argvec[count].partial != 0
2351 #ifdef REG_PARM_STACK_SPACE
2355 args_size.constant += argvec[count].size.constant;
2357 #ifdef ACCUMULATE_OUTGOING_ARGS
2358 /* If this arg is actually passed on the stack, it might be
2359 clobbering something we already put there (this library call might
2360 be inside the evaluation of an argument to a function whose call
2361 requires the stack). This will only occur when the library call
2362 has sufficient args to run out of argument registers. Abort in
2363 this case; if this ever occurs, code must be added to save and
2364 restore the arg slot. */
2366 if (argvec[count].reg == 0 || argvec[count].partial != 0)
2370 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree)0, 1);
2374 /* If this machine requires an external definition for library
2375 functions, write one out. */
2376 assemble_external_libcall (fun);
2378 original_args_size = args_size;
2379 #ifdef STACK_BOUNDARY
2380 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2381 / STACK_BYTES) * STACK_BYTES);
2384 #ifdef REG_PARM_STACK_SPACE
2385 args_size.constant = MAX (args_size.constant,
2386 REG_PARM_STACK_SPACE (NULL_TREE));
2387 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2388 args_size.constant -= REG_PARM_STACK_SPACE (NULL_TREE);
2392 if (args_size.constant > current_function_outgoing_args_size)
2393 current_function_outgoing_args_size = args_size.constant;
2395 #ifdef ACCUMULATE_OUTGOING_ARGS
2396 args_size.constant = 0;
2399 #ifndef PUSH_ROUNDING
2400 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2403 #ifdef PUSH_ARGS_REVERSED
2404 #ifdef STACK_BOUNDARY
2405 /* If we push args individually in reverse order, perform stack alignment
2406 before the first push (the last arg). */
2408 anti_adjust_stack (GEN_INT (args_size.constant
2409 - original_args_size.constant));
2413 #ifdef PUSH_ARGS_REVERSED
2421 /* Push the args that need to be pushed. */
2423 for (count = 0; count < nargs; count++, argnum += inc)
2425 register enum machine_mode mode = argvec[argnum].mode;
2426 register rtx val = argvec[argnum].value;
2427 rtx reg = argvec[argnum].reg;
2428 int partial = argvec[argnum].partial;
2430 if (! (reg != 0 && partial == 0))
2431 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2432 argblock, GEN_INT (argvec[count].offset.constant));
2436 #ifndef PUSH_ARGS_REVERSED
2437 #ifdef STACK_BOUNDARY
2438 /* If we pushed args in forward order, perform stack alignment
2439 after pushing the last arg. */
2441 anti_adjust_stack (GEN_INT (args_size.constant
2442 - original_args_size.constant));
2446 #ifdef PUSH_ARGS_REVERSED
2452 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
2454 /* Now load any reg parms into their regs. */
2456 for (count = 0; count < nargs; count++, argnum += inc)
2458 register enum machine_mode mode = argvec[argnum].mode;
2459 register rtx val = argvec[argnum].value;
2460 rtx reg = argvec[argnum].reg;
2461 int partial = argvec[argnum].partial;
2463 if (reg != 0 && partial == 0)
2464 emit_move_insn (reg, val);
2468 /* For version 1.37, try deleting this entirely. */
2472 /* Any regs containing parms remain in use through the call. */
2473 for (count = 0; count < nargs; count++)
2474 if (argvec[count].reg != 0)
2475 use_reg (&call_fusage, argvec[count].reg);
2477 /* Don't allow popping to be deferred, since then
2478 cse'ing of library calls could delete a call and leave the pop. */
2481 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2482 will set inhibit_defer_pop to that value. */
2485 get_identifier (XSTR (orgfun, 0)),
2486 get_identifier (XSTR (orgfun, 0)), args_size.constant, 0,
2487 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2488 outmode != VOIDmode ? hard_libcall_value (outmode) : NULL_RTX,
2489 old_inhibit_defer_pop + 1, call_fusage, no_queue);
2493 /* Now restore inhibit_defer_pop to its actual original value. */
2497 /* Like emit_library_call except that an extra argument, VALUE,
2498 comes second and says where to store the result.
2499 (If VALUE is zero, this function chooses a convenient way
2500 to return the value.
2502 This function returns an rtx for where the value is to be found.
2503 If VALUE is nonzero, VALUE is returned. */
2506 emit_library_call_value VPROTO((rtx orgfun, rtx value, int no_queue,
2507 enum machine_mode outmode, int nargs, ...))
2513 enum machine_mode outmode;
2517 /* Total size in bytes of all the stack-parms scanned so far. */
2518 struct args_size args_size;
2519 /* Size of arguments before any adjustments (such as rounding). */
2520 struct args_size original_args_size;
2521 register int argnum;
2526 CUMULATIVE_ARGS args_so_far;
2527 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2528 struct args_size offset; struct args_size size; };
2530 int old_inhibit_defer_pop = inhibit_defer_pop;
2531 rtx call_fusage = 0;
2533 int pcc_struct_value = 0;
2534 int struct_value_size = 0;
2537 VA_START (p, nargs);
2540 orgfun = va_arg (p, rtx);
2541 value = va_arg (p, rtx);
2542 no_queue = va_arg (p, int);
2543 outmode = va_arg (p, enum machine_mode);
2544 nargs = va_arg (p, int);
2547 is_const = no_queue;
2550 /* If this kind of value comes back in memory,
2551 decide where in memory it should come back. */
2552 if (aggregate_value_p (type_for_mode (outmode, 0)))
2554 #ifdef PCC_STATIC_STRUCT_RETURN
2556 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
2558 mem_value = gen_rtx (MEM, outmode, pointer_reg);
2559 pcc_struct_value = 1;
2561 value = gen_reg_rtx (outmode);
2562 #else /* not PCC_STATIC_STRUCT_RETURN */
2563 struct_value_size = GET_MODE_SIZE (outmode);
2564 if (value != 0 && GET_CODE (value) == MEM)
2567 mem_value = assign_stack_temp (outmode, GET_MODE_SIZE (outmode), 0);
2570 /* This call returns a big structure. */
2574 /* ??? Unfinished: must pass the memory address as an argument. */
2576 /* Copy all the libcall-arguments out of the varargs data
2577 and into a vector ARGVEC.
2579 Compute how to pass each argument. We only support a very small subset
2580 of the full argument passing conventions to limit complexity here since
2581 library functions shouldn't have many args. */
2583 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
2585 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
2587 args_size.constant = 0;
2594 /* If there's a structure value address to be passed,
2595 either pass it in the special place, or pass it as an extra argument. */
2596 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
2598 rtx addr = XEXP (mem_value, 0);
2601 /* Make sure it is a reasonable operand for a move or push insn. */
2602 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
2603 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
2604 addr = force_operand (addr, NULL_RTX);
2606 argvec[count].value = addr;
2607 argvec[count].mode = Pmode;
2608 argvec[count].partial = 0;
2610 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
2611 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2612 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
2616 locate_and_pad_parm (Pmode, NULL_TREE,
2617 argvec[count].reg && argvec[count].partial == 0,
2618 NULL_TREE, &args_size, &argvec[count].offset,
2619 &argvec[count].size);
2622 if (argvec[count].reg == 0 || argvec[count].partial != 0
2623 #ifdef REG_PARM_STACK_SPACE
2627 args_size.constant += argvec[count].size.constant;
2629 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree)0, 1);
2634 for (; count < nargs; count++)
2636 rtx val = va_arg (p, rtx);
2637 enum machine_mode mode = va_arg (p, enum machine_mode);
2639 /* We cannot convert the arg value to the mode the library wants here;
2640 must do it earlier where we know the signedness of the arg. */
2642 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2645 /* On some machines, there's no way to pass a float to a library fcn.
2646 Pass it as a double instead. */
2647 #ifdef LIBGCC_NEEDS_DOUBLE
2648 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2649 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
2652 /* There's no need to call protect_from_queue, because
2653 either emit_move_insn or emit_push_insn will do that. */
2655 /* Make sure it is a reasonable operand for a move or push insn. */
2656 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2657 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2658 val = force_operand (val, NULL_RTX);
2660 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2661 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2663 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2664 be viewed as just an efficiency improvement. */
2665 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2666 emit_move_insn (slot, val);
2667 val = XEXP (slot, 0);
2672 argvec[count].value = val;
2673 argvec[count].mode = mode;
2675 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2676 if (argvec[count].reg && GET_CODE (argvec[count].reg) == EXPR_LIST)
2678 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2679 argvec[count].partial
2680 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2682 argvec[count].partial = 0;
2685 locate_and_pad_parm (mode, NULL_TREE,
2686 argvec[count].reg && argvec[count].partial == 0,
2687 NULL_TREE, &args_size, &argvec[count].offset,
2688 &argvec[count].size);
2690 if (argvec[count].size.var)
2693 #ifndef REG_PARM_STACK_SPACE
2694 if (argvec[count].partial)
2695 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2698 if (argvec[count].reg == 0 || argvec[count].partial != 0
2699 #ifdef REG_PARM_STACK_SPACE
2703 args_size.constant += argvec[count].size.constant;
2705 #ifdef ACCUMULATE_OUTGOING_ARGS
2706 /* If this arg is actually passed on the stack, it might be
2707 clobbering something we already put there (this library call might
2708 be inside the evaluation of an argument to a function whose call
2709 requires the stack). This will only occur when the library call
2710 has sufficient args to run out of argument registers. Abort in
2711 this case; if this ever occurs, code must be added to save and
2712 restore the arg slot. */
2714 if (argvec[count].reg == 0 || argvec[count].partial != 0)
2718 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree)0, 1);
2722 /* If this machine requires an external definition for library
2723 functions, write one out. */
2724 assemble_external_libcall (fun);
2726 original_args_size = args_size;
2727 #ifdef STACK_BOUNDARY
2728 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2729 / STACK_BYTES) * STACK_BYTES);
2732 #ifdef REG_PARM_STACK_SPACE
2733 args_size.constant = MAX (args_size.constant,
2734 REG_PARM_STACK_SPACE (NULL_TREE));
2735 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2736 args_size.constant -= REG_PARM_STACK_SPACE (NULL_TREE);
2740 if (args_size.constant > current_function_outgoing_args_size)
2741 current_function_outgoing_args_size = args_size.constant;
2743 #ifdef ACCUMULATE_OUTGOING_ARGS
2744 args_size.constant = 0;
2747 #ifndef PUSH_ROUNDING
2748 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2751 #ifdef PUSH_ARGS_REVERSED
2752 #ifdef STACK_BOUNDARY
2753 /* If we push args individually in reverse order, perform stack alignment
2754 before the first push (the last arg). */
2756 anti_adjust_stack (GEN_INT (args_size.constant
2757 - original_args_size.constant));
2761 #ifdef PUSH_ARGS_REVERSED
2769 /* Push the args that need to be pushed. */
2771 for (count = 0; count < nargs; count++, argnum += inc)
2773 register enum machine_mode mode = argvec[argnum].mode;
2774 register rtx val = argvec[argnum].value;
2775 rtx reg = argvec[argnum].reg;
2776 int partial = argvec[argnum].partial;
2778 if (! (reg != 0 && partial == 0))
2779 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2780 argblock, GEN_INT (argvec[count].offset.constant));
2784 #ifndef PUSH_ARGS_REVERSED
2785 #ifdef STACK_BOUNDARY
2786 /* If we pushed args in forward order, perform stack alignment
2787 after pushing the last arg. */
2789 anti_adjust_stack (GEN_INT (args_size.constant
2790 - original_args_size.constant));
2794 #ifdef PUSH_ARGS_REVERSED
2800 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
2802 /* Now load any reg parms into their regs. */
2804 for (count = 0; count < nargs; count++, argnum += inc)
2806 register enum machine_mode mode = argvec[argnum].mode;
2807 register rtx val = argvec[argnum].value;
2808 rtx reg = argvec[argnum].reg;
2809 int partial = argvec[argnum].partial;
2811 if (reg != 0 && partial == 0)
2812 emit_move_insn (reg, val);
2817 /* For version 1.37, try deleting this entirely. */
2822 /* Any regs containing parms remain in use through the call. */
2823 for (count = 0; count < nargs; count++)
2824 if (argvec[count].reg != 0)
2825 use_reg (&call_fusage, argvec[count].reg);
2827 /* Pass the function the address in which to return a structure value. */
2828 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
2830 emit_move_insn (struct_value_rtx,
2832 force_operand (XEXP (mem_value, 0),
2834 if (GET_CODE (struct_value_rtx) == REG)
2835 use_reg (&call_fusage, struct_value_rtx);
2838 /* Don't allow popping to be deferred, since then
2839 cse'ing of library calls could delete a call and leave the pop. */
2842 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2843 will set inhibit_defer_pop to that value. */
2846 get_identifier (XSTR (orgfun, 0)),
2847 get_identifier (XSTR (orgfun, 0)), args_size.constant,
2849 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2850 (outmode != VOIDmode && mem_value == 0
2851 ? hard_libcall_value (outmode) : NULL_RTX),
2852 old_inhibit_defer_pop + 1, call_fusage, is_const);
2854 /* Now restore inhibit_defer_pop to its actual original value. */
2859 /* Copy the value to the right place. */
2860 if (outmode != VOIDmode)
2866 if (value != mem_value)
2867 emit_move_insn (value, mem_value);
2869 else if (value != 0)
2870 emit_move_insn (value, hard_libcall_value (outmode));
2872 value = hard_libcall_value (outmode);
2879 /* Return an rtx which represents a suitable home on the stack
2880 given TYPE, the type of the argument looking for a home.
2881 This is called only for BLKmode arguments.
2883 SIZE is the size needed for this target.
2884 ARGS_ADDR is the address of the bottom of the argument block for this call.
2885 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
2886 if this machine uses push insns. */
2889 target_for_arg (type, size, args_addr, offset)
2893 struct args_size offset;
2896 rtx offset_rtx = ARGS_SIZE_RTX (offset);
2898 /* We do not call memory_address if possible,
2899 because we want to address as close to the stack
2900 as possible. For non-variable sized arguments,
2901 this will be stack-pointer relative addressing. */
2902 if (GET_CODE (offset_rtx) == CONST_INT)
2903 target = plus_constant (args_addr, INTVAL (offset_rtx));
2906 /* I have no idea how to guarantee that this
2907 will work in the presence of register parameters. */
2908 target = gen_rtx (PLUS, Pmode, args_addr, offset_rtx);
2909 target = memory_address (QImode, target);
2912 return gen_rtx (MEM, BLKmode, target);
2916 /* Store a single argument for a function call
2917 into the register or memory area where it must be passed.
2918 *ARG describes the argument value and where to pass it.
2920 ARGBLOCK is the address of the stack-block for all the arguments,
2921 or 0 on a machine where arguments are pushed individually.
2923 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
2924 so must be careful about how the stack is used.
2926 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
2927 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
2928 that we need not worry about saving and restoring the stack.
2930 FNDECL is the declaration of the function we are calling. */
2933 store_one_arg (arg, argblock, may_be_alloca, variable_size, fndecl,
2934 reg_parm_stack_space)
2935 struct arg_data *arg;
2940 int reg_parm_stack_space;
2942 register tree pval = arg->tree_value;
2946 int i, lower_bound, upper_bound;
2948 if (TREE_CODE (pval) == ERROR_MARK)
2951 /* Push a new temporary level for any temporaries we make for
2955 #ifdef ACCUMULATE_OUTGOING_ARGS
2956 /* If this is being stored into a pre-allocated, fixed-size, stack area,
2957 save any previous data at that location. */
2958 if (argblock && ! variable_size && arg->stack)
2960 #ifdef ARGS_GROW_DOWNWARD
2961 /* stack_slot is negative, but we want to index stack_usage_map */
2962 /* with positive values. */
2963 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
2964 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
2968 lower_bound = upper_bound - arg->size.constant;
2970 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
2971 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
2975 upper_bound = lower_bound + arg->size.constant;
2978 for (i = lower_bound; i < upper_bound; i++)
2979 if (stack_usage_map[i]
2980 #ifdef REG_PARM_STACK_SPACE
2981 /* Don't store things in the fixed argument area at this point;
2982 it has already been saved. */
2983 && i > reg_parm_stack_space
2988 if (i != upper_bound)
2990 /* We need to make a save area. See what mode we can make it. */
2991 enum machine_mode save_mode
2992 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
2994 = gen_rtx (MEM, save_mode,
2995 memory_address (save_mode, XEXP (arg->stack_slot, 0)));
2997 if (save_mode == BLKmode)
2999 arg->save_area = assign_stack_temp (BLKmode,
3000 arg->size.constant, 0);
3001 MEM_IN_STRUCT_P (arg->save_area)
3002 = AGGREGATE_TYPE_P (TREE_TYPE (arg->tree_value));
3003 preserve_temp_slots (arg->save_area);
3004 emit_block_move (validize_mem (arg->save_area), stack_area,
3005 GEN_INT (arg->size.constant),
3006 PARM_BOUNDARY / BITS_PER_UNIT);
3010 arg->save_area = gen_reg_rtx (save_mode);
3011 emit_move_insn (arg->save_area, stack_area);
3017 /* If this isn't going to be placed on both the stack and in registers,
3018 set up the register and number of words. */
3019 if (! arg->pass_on_stack)
3020 reg = arg->reg, partial = arg->partial;
3022 if (reg != 0 && partial == 0)
3023 /* Being passed entirely in a register. We shouldn't be called in
3027 /* If this arg needs special alignment, don't load the registers
3029 if (arg->n_aligned_regs != 0)
3032 /* If this is being partially passed in a register, but multiple locations
3033 are specified, we assume that the one partially used is the one that is
3035 if (reg && GET_CODE (reg) == EXPR_LIST)
3036 reg = XEXP (reg, 0);
3038 /* If this is being passed partially in a register, we can't evaluate
3039 it directly into its stack slot. Otherwise, we can. */
3040 if (arg->value == 0)
3042 #ifdef ACCUMULATE_OUTGOING_ARGS
3043 /* stack_arg_under_construction is nonzero if a function argument is
3044 being evaluated directly into the outgoing argument list and
3045 expand_call must take special action to preserve the argument list
3046 if it is called recursively.
3048 For scalar function arguments stack_usage_map is sufficient to
3049 determine which stack slots must be saved and restored. Scalar
3050 arguments in general have pass_on_stack == 0.
3052 If this argument is initialized by a function which takes the
3053 address of the argument (a C++ constructor or a C function
3054 returning a BLKmode structure), then stack_usage_map is
3055 insufficient and expand_call must push the stack around the
3056 function call. Such arguments have pass_on_stack == 1.
3058 Note that it is always safe to set stack_arg_under_construction,
3059 but this generates suboptimal code if set when not needed. */
3061 if (arg->pass_on_stack)
3062 stack_arg_under_construction++;
3064 arg->value = expand_expr (pval,
3066 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
3067 ? NULL_RTX : arg->stack,
3070 /* If we are promoting object (or for any other reason) the mode
3071 doesn't agree, convert the mode. */
3073 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
3074 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
3075 arg->value, arg->unsignedp);
3077 #ifdef ACCUMULATE_OUTGOING_ARGS
3078 if (arg->pass_on_stack)
3079 stack_arg_under_construction--;
3083 /* Don't allow anything left on stack from computation
3084 of argument to alloca. */
3086 do_pending_stack_adjust ();
3088 if (arg->value == arg->stack)
3089 /* If the value is already in the stack slot, we are done. */
3091 else if (arg->mode != BLKmode)
3095 /* Argument is a scalar, not entirely passed in registers.
3096 (If part is passed in registers, arg->partial says how much
3097 and emit_push_insn will take care of putting it there.)
3099 Push it, and if its size is less than the
3100 amount of space allocated to it,
3101 also bump stack pointer by the additional space.
3102 Note that in C the default argument promotions
3103 will prevent such mismatches. */
3105 size = GET_MODE_SIZE (arg->mode);
3106 /* Compute how much space the push instruction will push.
3107 On many machines, pushing a byte will advance the stack
3108 pointer by a halfword. */
3109 #ifdef PUSH_ROUNDING
3110 size = PUSH_ROUNDING (size);
3114 /* Compute how much space the argument should get:
3115 round up to a multiple of the alignment for arguments. */
3116 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
3117 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
3118 / (PARM_BOUNDARY / BITS_PER_UNIT))
3119 * (PARM_BOUNDARY / BITS_PER_UNIT));
3121 /* This isn't already where we want it on the stack, so put it there.
3122 This can either be done with push or copy insns. */
3123 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
3124 0, partial, reg, used - size,
3125 argblock, ARGS_SIZE_RTX (arg->offset));
3129 /* BLKmode, at least partly to be pushed. */
3131 register int excess;
3134 /* Pushing a nonscalar.
3135 If part is passed in registers, PARTIAL says how much
3136 and emit_push_insn will take care of putting it there. */
3138 /* Round its size up to a multiple
3139 of the allocation unit for arguments. */
3141 if (arg->size.var != 0)
3144 size_rtx = ARGS_SIZE_RTX (arg->size);
3148 /* PUSH_ROUNDING has no effect on us, because
3149 emit_push_insn for BLKmode is careful to avoid it. */
3150 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
3151 + partial * UNITS_PER_WORD);
3152 size_rtx = expr_size (pval);
3155 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
3156 TYPE_ALIGN (TREE_TYPE (pval)) / BITS_PER_UNIT, partial,
3157 reg, excess, argblock, ARGS_SIZE_RTX (arg->offset));
3161 /* Unless this is a partially-in-register argument, the argument is now
3164 ??? Note that this can change arg->value from arg->stack to
3165 arg->stack_slot and it matters when they are not the same.
3166 It isn't totally clear that this is correct in all cases. */
3168 arg->value = arg->stack_slot;
3170 /* Once we have pushed something, pops can't safely
3171 be deferred during the rest of the arguments. */
3174 /* ANSI doesn't require a sequence point here,
3175 but PCC has one, so this will avoid some problems. */
3178 /* Free any temporary slots made in processing this argument. Show
3179 that we might have taken the address of something and pushed that
3181 preserve_temp_slots (NULL_RTX);
3185 #ifdef ACCUMULATE_OUTGOING_ARGS
3186 /* Now mark the segment we just used. */
3187 if (argblock && ! variable_size && arg->stack)
3188 for (i = lower_bound; i < upper_bound; i++)
3189 stack_usage_map[i] = 1;