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 PARALLEL if the arg is to be copied into multiple non-contiguous
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 to 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)
743 = before_call ? NEXT_INSN (before_call) : get_insns ();
746 /* Look for a call in the inline function code.
747 If OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl)) is
748 nonzero then there is a call and it is not necessary
749 to scan the insns. */
751 if (OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl)) == 0)
752 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
753 if (GET_CODE (insn) == CALL_INSN)
758 /* Reserve enough stack space so that the largest
759 argument list of any function call in the inline
760 function does not overlap the argument list being
761 evaluated. This is usually an overestimate because
762 allocate_dynamic_stack_space reserves space for an
763 outgoing argument list in addition to the requested
764 space, but there is no way to ask for stack space such
765 that an argument list of a certain length can be
766 safely constructed. */
768 int adjust = OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl));
769 #ifdef REG_PARM_STACK_SPACE
770 /* Add the stack space reserved for register arguments
771 in the inline function. What is really needed is the
772 largest value of reg_parm_stack_space in the inline
773 function, but that is not available. Using the current
774 value of reg_parm_stack_space is wrong, but gives
775 correct results on all supported machines. */
776 adjust += reg_parm_stack_space;
779 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
780 allocate_dynamic_stack_space (GEN_INT (adjust),
781 NULL_RTX, BITS_PER_UNIT);
784 emit_insns_before (seq, first_insn);
785 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
790 /* If the result is equivalent to TARGET, return TARGET to simplify
791 checks in store_expr. They can be equivalent but not equal in the
792 case of a function that returns BLKmode. */
793 if (temp != target && rtx_equal_p (temp, target))
798 /* If inlining failed, mark FNDECL as needing to be compiled
799 separately after all. If function was declared inline,
801 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
802 && optimize > 0 && ! TREE_ADDRESSABLE (fndecl))
804 warning_with_decl (fndecl, "inlining failed in call to `%s'");
805 warning ("called from here");
807 mark_addressable (fndecl);
810 /* When calling a const function, we must pop the stack args right away,
811 so that the pop is deleted or moved with the call. */
815 function_call_count++;
817 if (fndecl && DECL_NAME (fndecl))
818 name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
821 /* Unless it's a call to a specific function that isn't alloca,
822 if it has one argument, we must assume it might be alloca. */
825 (!(fndecl != 0 && strcmp (name, "alloca"))
827 && TREE_CHAIN (actparms) == 0);
829 /* We assume that alloca will always be called by name. It
830 makes no sense to pass it as a pointer-to-function to
831 anything that does not understand its behavior. */
833 (name && ((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
835 && ! strcmp (name, "alloca"))
836 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
838 && ! strcmp (name, "__builtin_alloca"))));
841 /* See if this is a call to a function that can return more than once
842 or a call to longjmp. */
847 if (name != 0 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 15)
851 /* Disregard prefix _, __ or __x. */
854 if (name[1] == '_' && name[2] == 'x')
856 else if (name[1] == '_')
866 && (! strcmp (tname, "setjmp")
867 || ! strcmp (tname, "setjmp_syscall")))
869 && ! strcmp (tname, "sigsetjmp"))
871 && ! strcmp (tname, "savectx")));
873 && ! strcmp (tname, "siglongjmp"))
876 else if ((tname[0] == 'q' && tname[1] == 's'
877 && ! strcmp (tname, "qsetjmp"))
878 || (tname[0] == 'v' && tname[1] == 'f'
879 && ! strcmp (tname, "vfork")))
882 else if (tname[0] == 'l' && tname[1] == 'o'
883 && ! strcmp (tname, "longjmp"))
888 current_function_calls_alloca = 1;
890 /* Don't let pending stack adjusts add up to too much.
891 Also, do all pending adjustments now
892 if there is any chance this might be a call to alloca. */
894 if (pending_stack_adjust >= 32
895 || (pending_stack_adjust > 0 && may_be_alloca))
896 do_pending_stack_adjust ();
898 /* Operand 0 is a pointer-to-function; get the type of the function. */
899 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
900 if (TREE_CODE (funtype) != POINTER_TYPE)
902 funtype = TREE_TYPE (funtype);
904 /* Push the temporary stack slot level so that we can free any temporaries
908 /* Start updating where the next arg would go.
910 On some machines (such as the PA) indirect calls have a different
911 calling convention than normal calls. The last argument in
912 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
914 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
916 /* If struct_value_rtx is 0, it means pass the address
917 as if it were an extra parameter. */
918 if (structure_value_addr && struct_value_rtx == 0)
920 /* If structure_value_addr is a REG other than
921 virtual_outgoing_args_rtx, we can use always use it. If it
922 is not a REG, we must always copy it into a register.
923 If it is virtual_outgoing_args_rtx, we must copy it to another
924 register in some cases. */
925 rtx temp = (GET_CODE (structure_value_addr) != REG
926 #ifdef ACCUMULATE_OUTGOING_ARGS
927 || (stack_arg_under_construction
928 && structure_value_addr == virtual_outgoing_args_rtx)
930 ? copy_addr_to_reg (structure_value_addr)
931 : structure_value_addr);
934 = tree_cons (error_mark_node,
935 make_tree (build_pointer_type (TREE_TYPE (funtype)),
938 structure_value_addr_parm = 1;
941 /* Count the arguments and set NUM_ACTUALS. */
942 for (p = actparms, i = 0; p; p = TREE_CHAIN (p)) i++;
945 /* Compute number of named args.
946 Normally, don't include the last named arg if anonymous args follow.
947 We do include the last named arg if STRICT_ARGUMENT_NAMING is defined.
948 (If no anonymous args follow, the result of list_length is actually
949 one too large. This is harmless.)
951 If SETUP_INCOMING_VARARGS is defined and STRICT_ARGUMENT_NAMING is not,
952 this machine will be able to place unnamed args that were passed in
953 registers into the stack. So treat all args as named. This allows the
954 insns emitting for a specific argument list to be independent of the
955 function declaration.
957 If SETUP_INCOMING_VARARGS is not defined, we do not have any reliable
958 way to pass unnamed args in registers, so we must force them into
960 #if !defined(SETUP_INCOMING_VARARGS) || defined(STRICT_ARGUMENT_NAMING)
961 if (TYPE_ARG_TYPES (funtype) != 0)
963 = (list_length (TYPE_ARG_TYPES (funtype))
964 #ifndef STRICT_ARGUMENT_NAMING
965 /* Don't include the last named arg. */
968 /* Count the struct value address, if it is passed as a parm. */
969 + structure_value_addr_parm);
972 /* If we know nothing, treat all args as named. */
973 n_named_args = num_actuals;
975 /* Make a vector to hold all the information about each arg. */
976 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
977 bzero ((char *) args, num_actuals * sizeof (struct arg_data));
979 args_size.constant = 0;
982 /* In this loop, we consider args in the order they are written.
983 We fill up ARGS from the front or from the back if necessary
984 so that in any case the first arg to be pushed ends up at the front. */
986 #ifdef PUSH_ARGS_REVERSED
987 i = num_actuals - 1, inc = -1;
988 /* In this case, must reverse order of args
989 so that we compute and push the last arg first. */
994 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
995 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
997 tree type = TREE_TYPE (TREE_VALUE (p));
999 enum machine_mode mode;
1001 args[i].tree_value = TREE_VALUE (p);
1003 /* Replace erroneous argument with constant zero. */
1004 if (type == error_mark_node || TYPE_SIZE (type) == 0)
1005 args[i].tree_value = integer_zero_node, type = integer_type_node;
1007 /* If TYPE is a transparent union, pass things the way we would
1008 pass the first field of the union. We have already verified that
1009 the modes are the same. */
1010 if (TYPE_TRANSPARENT_UNION (type))
1011 type = TREE_TYPE (TYPE_FIELDS (type));
1013 /* Decide where to pass this arg.
1015 args[i].reg is nonzero if all or part is passed in registers.
1017 args[i].partial is nonzero if part but not all is passed in registers,
1018 and the exact value says how many words are passed in registers.
1020 args[i].pass_on_stack is nonzero if the argument must at least be
1021 computed on the stack. It may then be loaded back into registers
1022 if args[i].reg is nonzero.
1024 These decisions are driven by the FUNCTION_... macros and must agree
1025 with those made by function.c. */
1027 /* See if this argument should be passed by invisible reference. */
1028 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1029 && contains_placeholder_p (TYPE_SIZE (type)))
1030 || TREE_ADDRESSABLE (type)
1031 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1032 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, TYPE_MODE (type),
1033 type, argpos < n_named_args)
1037 #ifdef FUNCTION_ARG_CALLEE_COPIES
1038 if (FUNCTION_ARG_CALLEE_COPIES (args_so_far, TYPE_MODE (type), type,
1039 argpos < n_named_args)
1040 /* If it's in a register, we must make a copy of it too. */
1041 /* ??? Is this a sufficient test? Is there a better one? */
1042 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1043 && REG_P (DECL_RTL (args[i].tree_value)))
1044 && ! TREE_ADDRESSABLE (type))
1046 args[i].tree_value = build1 (ADDR_EXPR,
1047 build_pointer_type (type),
1048 args[i].tree_value);
1049 type = build_pointer_type (type);
1054 /* We make a copy of the object and pass the address to the
1055 function being called. */
1058 if (TYPE_SIZE (type) == 0
1059 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
1061 /* This is a variable-sized object. Make space on the stack
1063 rtx size_rtx = expr_size (TREE_VALUE (p));
1065 if (old_stack_level == 0)
1067 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1068 old_pending_adj = pending_stack_adjust;
1069 pending_stack_adjust = 0;
1072 copy = gen_rtx (MEM, BLKmode,
1073 allocate_dynamic_stack_space (size_rtx,
1075 TYPE_ALIGN (type)));
1079 int size = int_size_in_bytes (type);
1080 copy = assign_stack_temp (TYPE_MODE (type), size, 0);
1083 MEM_IN_STRUCT_P (copy) = AGGREGATE_TYPE_P (type);
1085 store_expr (args[i].tree_value, copy, 0);
1088 args[i].tree_value = build1 (ADDR_EXPR,
1089 build_pointer_type (type),
1090 make_tree (type, copy));
1091 type = build_pointer_type (type);
1095 mode = TYPE_MODE (type);
1096 unsignedp = TREE_UNSIGNED (type);
1098 #ifdef PROMOTE_FUNCTION_ARGS
1099 mode = promote_mode (type, mode, &unsignedp, 1);
1102 args[i].unsignedp = unsignedp;
1103 args[i].mode = mode;
1104 args[i].reg = FUNCTION_ARG (args_so_far, mode, type,
1105 argpos < n_named_args);
1106 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1109 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, type,
1110 argpos < n_named_args);
1113 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1115 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1116 it means that we are to pass this arg in the register(s) designated
1117 by the PARALLEL, but also to pass it in the stack. */
1118 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1119 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1120 args[i].pass_on_stack = 1;
1122 /* If this is an addressable type, we must preallocate the stack
1123 since we must evaluate the object into its final location.
1125 If this is to be passed in both registers and the stack, it is simpler
1127 if (TREE_ADDRESSABLE (type)
1128 || (args[i].pass_on_stack && args[i].reg != 0))
1129 must_preallocate = 1;
1131 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1132 we cannot consider this function call constant. */
1133 if (TREE_ADDRESSABLE (type))
1136 /* Compute the stack-size of this argument. */
1137 if (args[i].reg == 0 || args[i].partial != 0
1138 #ifdef REG_PARM_STACK_SPACE
1139 || reg_parm_stack_space > 0
1141 || args[i].pass_on_stack)
1142 locate_and_pad_parm (mode, type,
1143 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1148 fndecl, &args_size, &args[i].offset,
1151 #ifndef ARGS_GROW_DOWNWARD
1152 args[i].slot_offset = args_size;
1155 #ifndef REG_PARM_STACK_SPACE
1156 /* If a part of the arg was put into registers,
1157 don't include that part in the amount pushed. */
1158 if (! args[i].pass_on_stack)
1159 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1160 / (PARM_BOUNDARY / BITS_PER_UNIT)
1161 * (PARM_BOUNDARY / BITS_PER_UNIT));
1164 /* Update ARGS_SIZE, the total stack space for args so far. */
1166 args_size.constant += args[i].size.constant;
1167 if (args[i].size.var)
1169 ADD_PARM_SIZE (args_size, args[i].size.var);
1172 /* Since the slot offset points to the bottom of the slot,
1173 we must record it after incrementing if the args grow down. */
1174 #ifdef ARGS_GROW_DOWNWARD
1175 args[i].slot_offset = args_size;
1177 args[i].slot_offset.constant = -args_size.constant;
1180 SUB_PARM_SIZE (args[i].slot_offset, args_size.var);
1184 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1185 have been used, etc. */
1187 FUNCTION_ARG_ADVANCE (args_so_far, TYPE_MODE (type), type,
1188 argpos < n_named_args);
1191 #ifdef FINAL_REG_PARM_STACK_SPACE
1192 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
1196 /* Compute the actual size of the argument block required. The variable
1197 and constant sizes must be combined, the size may have to be rounded,
1198 and there may be a minimum required size. */
1200 original_args_size = args_size;
1203 /* If this function requires a variable-sized argument list, don't try to
1204 make a cse'able block for this call. We may be able to do this
1205 eventually, but it is too complicated to keep track of what insns go
1206 in the cse'able block and which don't. */
1209 must_preallocate = 1;
1211 args_size.var = ARGS_SIZE_TREE (args_size);
1212 args_size.constant = 0;
1214 #ifdef STACK_BOUNDARY
1215 if (STACK_BOUNDARY != BITS_PER_UNIT)
1216 args_size.var = round_up (args_size.var, STACK_BYTES);
1219 #ifdef REG_PARM_STACK_SPACE
1220 if (reg_parm_stack_space > 0)
1223 = size_binop (MAX_EXPR, args_size.var,
1224 size_int (REG_PARM_STACK_SPACE (fndecl)));
1226 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1227 /* The area corresponding to register parameters is not to count in
1228 the size of the block we need. So make the adjustment. */
1230 = size_binop (MINUS_EXPR, args_size.var,
1231 size_int (reg_parm_stack_space));
1238 #ifdef STACK_BOUNDARY
1239 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
1240 / STACK_BYTES) * STACK_BYTES);
1243 #ifdef REG_PARM_STACK_SPACE
1244 args_size.constant = MAX (args_size.constant,
1245 reg_parm_stack_space);
1246 #ifdef MAYBE_REG_PARM_STACK_SPACE
1247 if (reg_parm_stack_space == 0)
1248 args_size.constant = 0;
1250 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1251 args_size.constant -= reg_parm_stack_space;
1256 /* See if we have or want to preallocate stack space.
1258 If we would have to push a partially-in-regs parm
1259 before other stack parms, preallocate stack space instead.
1261 If the size of some parm is not a multiple of the required stack
1262 alignment, we must preallocate.
1264 If the total size of arguments that would otherwise create a copy in
1265 a temporary (such as a CALL) is more than half the total argument list
1266 size, preallocation is faster.
1268 Another reason to preallocate is if we have a machine (like the m88k)
1269 where stack alignment is required to be maintained between every
1270 pair of insns, not just when the call is made. However, we assume here
1271 that such machines either do not have push insns (and hence preallocation
1272 would occur anyway) or the problem is taken care of with
1275 if (! must_preallocate)
1277 int partial_seen = 0;
1278 int copy_to_evaluate_size = 0;
1280 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1282 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1284 else if (partial_seen && args[i].reg == 0)
1285 must_preallocate = 1;
1287 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1288 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1289 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1290 || TREE_CODE (args[i].tree_value) == COND_EXPR
1291 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1292 copy_to_evaluate_size
1293 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1296 if (copy_to_evaluate_size * 2 >= args_size.constant
1297 && args_size.constant > 0)
1298 must_preallocate = 1;
1301 /* If the structure value address will reference the stack pointer, we must
1302 stabilize it. We don't need to do this if we know that we are not going
1303 to adjust the stack pointer in processing this call. */
1305 if (structure_value_addr
1306 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
1307 || reg_mentioned_p (virtual_outgoing_args_rtx, structure_value_addr))
1309 #ifndef ACCUMULATE_OUTGOING_ARGS
1310 || args_size.constant
1313 structure_value_addr = copy_to_reg (structure_value_addr);
1315 /* If this function call is cse'able, precompute all the parameters.
1316 Note that if the parameter is constructed into a temporary, this will
1317 cause an additional copy because the parameter will be constructed
1318 into a temporary location and then copied into the outgoing arguments.
1319 If a parameter contains a call to alloca and this function uses the
1320 stack, precompute the parameter. */
1322 /* If we preallocated the stack space, and some arguments must be passed
1323 on the stack, then we must precompute any parameter which contains a
1324 function call which will store arguments on the stack.
1325 Otherwise, evaluating the parameter may clobber previous parameters
1326 which have already been stored into the stack. */
1328 for (i = 0; i < num_actuals; i++)
1330 || ((args_size.var != 0 || args_size.constant != 0)
1331 && calls_function (args[i].tree_value, 1))
1332 || (must_preallocate && (args_size.var != 0 || args_size.constant != 0)
1333 && calls_function (args[i].tree_value, 0)))
1335 /* If this is an addressable type, we cannot pre-evaluate it. */
1336 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1341 args[i].initial_value = args[i].value
1342 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1344 preserve_temp_slots (args[i].value);
1347 /* ANSI doesn't require a sequence point here,
1348 but PCC has one, so this will avoid some problems. */
1351 args[i].initial_value = args[i].value
1352 = protect_from_queue (args[i].initial_value, 0);
1354 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) != args[i].mode)
1356 = convert_modes (args[i].mode,
1357 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1358 args[i].value, args[i].unsignedp);
1361 /* Now we are about to start emitting insns that can be deleted
1362 if a libcall is deleted. */
1366 /* If we have no actual push instructions, or shouldn't use them,
1367 make space for all args right now. */
1369 if (args_size.var != 0)
1371 if (old_stack_level == 0)
1373 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1374 old_pending_adj = pending_stack_adjust;
1375 pending_stack_adjust = 0;
1376 #ifdef ACCUMULATE_OUTGOING_ARGS
1377 /* stack_arg_under_construction says whether a stack arg is
1378 being constructed at the old stack level. Pushing the stack
1379 gets a clean outgoing argument block. */
1380 old_stack_arg_under_construction = stack_arg_under_construction;
1381 stack_arg_under_construction = 0;
1384 argblock = push_block (ARGS_SIZE_RTX (args_size), 0, 0);
1388 /* Note that we must go through the motions of allocating an argument
1389 block even if the size is zero because we may be storing args
1390 in the area reserved for register arguments, which may be part of
1393 int needed = args_size.constant;
1395 /* Store the maximum argument space used. It will be pushed by
1396 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
1399 if (needed > current_function_outgoing_args_size)
1400 current_function_outgoing_args_size = needed;
1402 if (must_preallocate)
1404 #ifdef ACCUMULATE_OUTGOING_ARGS
1405 /* Since the stack pointer will never be pushed, it is possible for
1406 the evaluation of a parm to clobber something we have already
1407 written to the stack. Since most function calls on RISC machines
1408 do not use the stack, this is uncommon, but must work correctly.
1410 Therefore, we save any area of the stack that was already written
1411 and that we are using. Here we set up to do this by making a new
1412 stack usage map from the old one. The actual save will be done
1415 Another approach might be to try to reorder the argument
1416 evaluations to avoid this conflicting stack usage. */
1418 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1419 /* Since we will be writing into the entire argument area, the
1420 map must be allocated for its entire size, not just the part that
1421 is the responsibility of the caller. */
1422 needed += reg_parm_stack_space;
1425 #ifdef ARGS_GROW_DOWNWARD
1426 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
1429 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
1432 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
1434 if (initial_highest_arg_in_use)
1435 bcopy (initial_stack_usage_map, stack_usage_map,
1436 initial_highest_arg_in_use);
1438 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
1439 bzero (&stack_usage_map[initial_highest_arg_in_use],
1440 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
1443 /* The address of the outgoing argument list must not be copied to a
1444 register here, because argblock would be left pointing to the
1445 wrong place after the call to allocate_dynamic_stack_space below.
1448 argblock = virtual_outgoing_args_rtx;
1450 #else /* not ACCUMULATE_OUTGOING_ARGS */
1451 if (inhibit_defer_pop == 0)
1453 /* Try to reuse some or all of the pending_stack_adjust
1454 to get this space. Maybe we can avoid any pushing. */
1455 if (needed > pending_stack_adjust)
1457 needed -= pending_stack_adjust;
1458 pending_stack_adjust = 0;
1462 pending_stack_adjust -= needed;
1466 /* Special case this because overhead of `push_block' in this
1467 case is non-trivial. */
1469 argblock = virtual_outgoing_args_rtx;
1471 argblock = push_block (GEN_INT (needed), 0, 0);
1473 /* We only really need to call `copy_to_reg' in the case where push
1474 insns are going to be used to pass ARGBLOCK to a function
1475 call in ARGS. In that case, the stack pointer changes value
1476 from the allocation point to the call point, and hence
1477 the value of VIRTUAL_OUTGOING_ARGS_RTX changes as well.
1478 But might as well always do it. */
1479 argblock = copy_to_reg (argblock);
1480 #endif /* not ACCUMULATE_OUTGOING_ARGS */
1484 #ifdef ACCUMULATE_OUTGOING_ARGS
1485 /* The save/restore code in store_one_arg handles all cases except one:
1486 a constructor call (including a C function returning a BLKmode struct)
1487 to initialize an argument. */
1488 if (stack_arg_under_construction)
1490 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1491 rtx push_size = GEN_INT (reg_parm_stack_space + args_size.constant);
1493 rtx push_size = GEN_INT (args_size.constant);
1495 if (old_stack_level == 0)
1497 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1498 old_pending_adj = pending_stack_adjust;
1499 pending_stack_adjust = 0;
1500 /* stack_arg_under_construction says whether a stack arg is
1501 being constructed at the old stack level. Pushing the stack
1502 gets a clean outgoing argument block. */
1503 old_stack_arg_under_construction = stack_arg_under_construction;
1504 stack_arg_under_construction = 0;
1505 /* Make a new map for the new argument list. */
1506 stack_usage_map = (char *)alloca (highest_outgoing_arg_in_use);
1507 bzero (stack_usage_map, highest_outgoing_arg_in_use);
1508 highest_outgoing_arg_in_use = 0;
1510 allocate_dynamic_stack_space (push_size, NULL_RTX, BITS_PER_UNIT);
1512 /* If argument evaluation might modify the stack pointer, copy the
1513 address of the argument list to a register. */
1514 for (i = 0; i < num_actuals; i++)
1515 if (args[i].pass_on_stack)
1517 argblock = copy_addr_to_reg (argblock);
1523 /* If we preallocated stack space, compute the address of each argument.
1524 We need not ensure it is a valid memory address here; it will be
1525 validized when it is used. */
1528 rtx arg_reg = argblock;
1531 if (GET_CODE (argblock) == PLUS)
1532 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1534 for (i = 0; i < num_actuals; i++)
1536 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1537 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1540 /* Skip this parm if it will not be passed on the stack. */
1541 if (! args[i].pass_on_stack && args[i].reg != 0)
1544 if (GET_CODE (offset) == CONST_INT)
1545 addr = plus_constant (arg_reg, INTVAL (offset));
1547 addr = gen_rtx (PLUS, Pmode, arg_reg, offset);
1549 addr = plus_constant (addr, arg_offset);
1550 args[i].stack = gen_rtx (MEM, args[i].mode, addr);
1551 MEM_IN_STRUCT_P (args[i].stack)
1552 = AGGREGATE_TYPE_P (TREE_TYPE (args[i].tree_value));
1554 if (GET_CODE (slot_offset) == CONST_INT)
1555 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1557 addr = gen_rtx (PLUS, Pmode, arg_reg, slot_offset);
1559 addr = plus_constant (addr, arg_offset);
1560 args[i].stack_slot = gen_rtx (MEM, args[i].mode, addr);
1564 #ifdef PUSH_ARGS_REVERSED
1565 #ifdef STACK_BOUNDARY
1566 /* If we push args individually in reverse order, perform stack alignment
1567 before the first push (the last arg). */
1569 anti_adjust_stack (GEN_INT (args_size.constant
1570 - original_args_size.constant));
1574 /* Don't try to defer pops if preallocating, not even from the first arg,
1575 since ARGBLOCK probably refers to the SP. */
1579 /* Get the function to call, in the form of RTL. */
1582 /* If this is the first use of the function, see if we need to
1583 make an external definition for it. */
1584 if (! TREE_USED (fndecl))
1586 assemble_external (fndecl);
1587 TREE_USED (fndecl) = 1;
1590 /* Get a SYMBOL_REF rtx for the function address. */
1591 funexp = XEXP (DECL_RTL (fndecl), 0);
1594 /* Generate an rtx (probably a pseudo-register) for the address. */
1597 funexp = expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1598 pop_temp_slots (); /* FUNEXP can't be BLKmode */
1602 /* Figure out the register where the value, if any, will come back. */
1604 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
1605 && ! structure_value_addr)
1607 if (pcc_struct_value)
1608 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
1611 valreg = hard_function_value (TREE_TYPE (exp), fndecl);
1614 /* Precompute all register parameters. It isn't safe to compute anything
1615 once we have started filling any specific hard regs. */
1617 for (i = 0; i < num_actuals; i++)
1618 if (args[i].reg != 0 && ! args[i].pass_on_stack)
1622 if (args[i].value == 0)
1625 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
1627 preserve_temp_slots (args[i].value);
1630 /* ANSI doesn't require a sequence point here,
1631 but PCC has one, so this will avoid some problems. */
1635 /* If we are to promote the function arg to a wider mode,
1638 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
1640 = convert_modes (args[i].mode,
1641 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1642 args[i].value, args[i].unsignedp);
1644 /* If the value is expensive, and we are inside an appropriately
1645 short loop, put the value into a pseudo and then put the pseudo
1648 For small register classes, also do this if this call uses
1649 register parameters. This is to avoid reload conflicts while
1650 loading the parameters registers. */
1652 if ((! (GET_CODE (args[i].value) == REG
1653 || (GET_CODE (args[i].value) == SUBREG
1654 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
1655 && args[i].mode != BLKmode
1656 && rtx_cost (args[i].value, SET) > 2
1657 #ifdef SMALL_REGISTER_CLASSES
1658 && (reg_parm_seen || preserve_subexpressions_p ())
1660 && preserve_subexpressions_p ()
1663 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
1666 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
1667 /* The argument list is the property of the called routine and it
1668 may clobber it. If the fixed area has been used for previous
1669 parameters, we must save and restore it.
1671 Here we compute the boundary of the that needs to be saved, if any. */
1673 #ifdef ARGS_GROW_DOWNWARD
1674 for (i = 0; i < reg_parm_stack_space + 1; i++)
1676 for (i = 0; i < reg_parm_stack_space; i++)
1679 if (i >= highest_outgoing_arg_in_use
1680 || stack_usage_map[i] == 0)
1683 if (low_to_save == -1)
1689 if (low_to_save >= 0)
1691 int num_to_save = high_to_save - low_to_save + 1;
1692 enum machine_mode save_mode
1693 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
1696 /* If we don't have the required alignment, must do this in BLKmode. */
1697 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
1698 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
1699 save_mode = BLKmode;
1701 stack_area = gen_rtx (MEM, save_mode,
1702 memory_address (save_mode,
1704 #ifdef ARGS_GROW_DOWNWARD
1705 plus_constant (argblock,
1708 plus_constant (argblock,
1712 if (save_mode == BLKmode)
1714 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
1715 MEM_IN_STRUCT_P (save_area) = 0;
1716 emit_block_move (validize_mem (save_area), stack_area,
1717 GEN_INT (num_to_save),
1718 PARM_BOUNDARY / BITS_PER_UNIT);
1722 save_area = gen_reg_rtx (save_mode);
1723 emit_move_insn (save_area, stack_area);
1729 /* Now store (and compute if necessary) all non-register parms.
1730 These come before register parms, since they can require block-moves,
1731 which could clobber the registers used for register parms.
1732 Parms which have partial registers are not stored here,
1733 but we do preallocate space here if they want that. */
1735 for (i = 0; i < num_actuals; i++)
1736 if (args[i].reg == 0 || args[i].pass_on_stack)
1737 store_one_arg (&args[i], argblock, may_be_alloca,
1738 args_size.var != 0, fndecl, reg_parm_stack_space);
1740 /* If we have a parm that is passed in registers but not in memory
1741 and whose alignment does not permit a direct copy into registers,
1742 make a group of pseudos that correspond to each register that we
1745 if (STRICT_ALIGNMENT)
1746 for (i = 0; i < num_actuals; i++)
1747 if (args[i].reg != 0 && ! args[i].pass_on_stack
1748 && args[i].mode == BLKmode
1749 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1750 < MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1752 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1753 int big_endian_correction = 0;
1755 args[i].n_aligned_regs
1756 = args[i].partial ? args[i].partial
1757 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1759 args[i].aligned_regs = (rtx *) alloca (sizeof (rtx)
1760 * args[i].n_aligned_regs);
1762 /* Structures smaller than a word are aligned to the least
1763 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1764 this means we must skip the empty high order bytes when
1765 calculating the bit offset. */
1766 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
1767 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1769 for (j = 0; j < args[i].n_aligned_regs; j++)
1771 rtx reg = gen_reg_rtx (word_mode);
1772 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1773 int bitsize = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
1776 args[i].aligned_regs[j] = reg;
1778 /* Clobber REG and move each partword into it. Ensure we don't
1779 go past the end of the structure. Note that the loop below
1780 works because we've already verified that padding
1781 and endianness are compatible. */
1783 emit_insn (gen_rtx (CLOBBER, VOIDmode, reg));
1786 bitpos < BITS_PER_WORD && bytes > 0;
1787 bitpos += bitsize, bytes -= bitsize / BITS_PER_UNIT)
1789 int xbitpos = bitpos + big_endian_correction;
1791 store_bit_field (reg, bitsize, xbitpos, word_mode,
1792 extract_bit_field (word, bitsize, bitpos, 1,
1793 NULL_RTX, word_mode,
1795 bitsize / BITS_PER_UNIT,
1797 bitsize / BITS_PER_UNIT, BITS_PER_WORD);
1802 /* Now store any partially-in-registers parm.
1803 This is the last place a block-move can happen. */
1805 for (i = 0; i < num_actuals; i++)
1806 if (args[i].partial != 0 && ! args[i].pass_on_stack)
1807 store_one_arg (&args[i], argblock, may_be_alloca,
1808 args_size.var != 0, fndecl, reg_parm_stack_space);
1810 #ifndef PUSH_ARGS_REVERSED
1811 #ifdef STACK_BOUNDARY
1812 /* If we pushed args in forward order, perform stack alignment
1813 after pushing the last arg. */
1815 anti_adjust_stack (GEN_INT (args_size.constant
1816 - original_args_size.constant));
1820 /* If register arguments require space on the stack and stack space
1821 was not preallocated, allocate stack space here for arguments
1822 passed in registers. */
1823 #if ! defined(ACCUMULATE_OUTGOING_ARGS) && defined(OUTGOING_REG_PARM_STACK_SPACE)
1824 if (must_preallocate == 0 && reg_parm_stack_space > 0)
1825 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
1828 /* Pass the function the address in which to return a structure value. */
1829 if (structure_value_addr && ! structure_value_addr_parm)
1831 emit_move_insn (struct_value_rtx,
1833 force_operand (structure_value_addr,
1835 if (GET_CODE (struct_value_rtx) == REG)
1836 use_reg (&call_fusage, struct_value_rtx);
1839 funexp = prepare_call_address (funexp, fndecl, &call_fusage, reg_parm_seen);
1841 /* Now do the register loads required for any wholly-register parms or any
1842 parms which are passed both on the stack and in a register. Their
1843 expressions were already evaluated.
1845 Mark all register-parms as living through the call, putting these USE
1846 insns in the CALL_INSN_FUNCTION_USAGE field. */
1848 for (i = 0; i < num_actuals; i++)
1850 rtx reg = args[i].reg;
1851 int partial = args[i].partial;
1856 /* Set to non-negative if must move a word at a time, even if just
1857 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1858 we just use a normal move insn. This value can be zero if the
1859 argument is a zero size structure with no fields. */
1860 nregs = (partial ? partial
1861 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1862 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1863 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1866 /* Handle calls that pass values in multiple non-contiguous
1867 locations. The Irix 6 ABI has examples of this. */
1869 if (GET_CODE (reg) == PARALLEL)
1870 emit_group_load (reg, args[i].value);
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. */
1876 else if (nregs == -1)
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 (partial == 0 || args[i].pass_on_stack)
1888 move_block_to_reg (REGNO (reg),
1889 validize_mem (args[i].value), nregs,
1892 /* Handle calls that pass values in multiple non-contiguous
1893 locations. The Irix 6 ABI has examples of this. */
1894 if (GET_CODE (reg) == PARALLEL)
1895 use_group_regs (&call_fusage, reg);
1896 else if (nregs == -1)
1897 use_reg (&call_fusage, reg);
1899 use_regs (&call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
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. Disable for PARALLEL return values, because
1916 we have no way to move such values into a pseudo register. */
1917 if (is_const && valreg != 0 && GET_CODE (valreg) != PARALLEL)
1920 rtx temp = gen_reg_rtx (GET_MODE (valreg));
1923 /* Construct an "equal form" for the value which mentions all the
1924 arguments in order as well as the function name. */
1925 #ifdef PUSH_ARGS_REVERSED
1926 for (i = 0; i < num_actuals; i++)
1927 note = gen_rtx (EXPR_LIST, VOIDmode, args[i].initial_value, note);
1929 for (i = num_actuals - 1; i >= 0; i--)
1930 note = gen_rtx (EXPR_LIST, VOIDmode, args[i].initial_value, note);
1932 note = gen_rtx (EXPR_LIST, VOIDmode, funexp, note);
1934 insns = get_insns ();
1937 emit_libcall_block (insns, temp, valreg, note);
1943 /* Otherwise, just write out the sequence without a note. */
1944 rtx insns = get_insns ();
1950 /* For calls to `setjmp', etc., inform flow.c it should complain
1951 if nonvolatile values are live. */
1955 emit_note (name, NOTE_INSN_SETJMP);
1956 current_function_calls_setjmp = 1;
1960 current_function_calls_longjmp = 1;
1962 /* Notice functions that cannot return.
1963 If optimizing, insns emitted below will be dead.
1964 If not optimizing, they will exist, which is useful
1965 if the user uses the `return' command in the debugger. */
1967 if (is_volatile || is_longjmp)
1970 /* If value type not void, return an rtx for the value. */
1972 /* If there are cleanups to be called, don't use a hard reg as target. */
1973 if (cleanups_this_call != old_cleanups
1974 && target && REG_P (target)
1975 && REGNO (target) < FIRST_PSEUDO_REGISTER)
1978 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
1981 target = const0_rtx;
1983 else if (structure_value_addr)
1985 if (target == 0 || GET_CODE (target) != MEM)
1987 target = gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)),
1988 memory_address (TYPE_MODE (TREE_TYPE (exp)),
1989 structure_value_addr));
1990 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
1993 else if (pcc_struct_value)
1997 /* We used leave the value in the location that it is
1998 returned in, but that causes problems if it is used more
1999 than once in one expression. Rather than trying to track
2000 when a copy is required, we always copy when TARGET is
2001 not specified. This calling sequence is only used on
2002 a few machines and TARGET is usually nonzero. */
2003 if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
2005 target = assign_stack_temp (BLKmode,
2006 int_size_in_bytes (TREE_TYPE (exp)),
2009 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
2011 /* Save this temp slot around the pop below. */
2012 preserve_temp_slots (target);
2015 target = gen_reg_rtx (TYPE_MODE (TREE_TYPE (exp)));
2018 if (TYPE_MODE (TREE_TYPE (exp)) != BLKmode)
2019 emit_move_insn (target, gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)),
2020 copy_to_reg (valreg)));
2022 emit_block_move (target, gen_rtx (MEM, BLKmode, copy_to_reg (valreg)),
2024 TYPE_ALIGN (TREE_TYPE (exp)) / BITS_PER_UNIT);
2026 /* Handle calls that return values in multiple non-contiguous locations.
2027 The Irix 6 ABI has examples of this. */
2028 else if (GET_CODE (valreg) == PARALLEL)
2032 int bytes = int_size_in_bytes (TREE_TYPE (exp));
2033 target = assign_stack_temp (TYPE_MODE (TREE_TYPE (exp)), bytes, 0);
2034 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
2035 preserve_temp_slots (target);
2038 emit_group_store (target, valreg);
2040 else if (target && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
2041 && GET_MODE (target) == GET_MODE (valreg))
2042 /* TARGET and VALREG cannot be equal at this point because the latter
2043 would not have REG_FUNCTION_VALUE_P true, while the former would if
2044 it were referring to the same register.
2046 If they refer to the same register, this move will be a no-op, except
2047 when function inlining is being done. */
2048 emit_move_insn (target, valreg);
2049 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
2051 /* Some machines (the PA for example) want to return all small
2052 structures in registers regardless of the structure's alignment.
2054 Deal with them explicitly by copying from the return registers
2055 into the target MEM locations. */
2056 int bytes = int_size_in_bytes (TREE_TYPE (exp));
2057 int n_regs = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
2059 enum machine_mode tmpmode;
2061 int bitsize = MIN (TYPE_ALIGN (TREE_TYPE (exp)), BITS_PER_WORD);
2062 int bitpos, xbitpos, big_endian_correction = 0;
2066 target = assign_stack_temp (BLKmode, bytes, 0);
2067 MEM_IN_STRUCT_P (target) = AGGREGATE_TYPE_P (TREE_TYPE (exp));
2068 preserve_temp_slots (target);
2071 /* This code assumes valreg is at least a full word. If it isn't,
2072 copy it into a new pseudo which is a full word. */
2073 if (GET_MODE (valreg) != BLKmode
2074 && GET_MODE_SIZE (GET_MODE (valreg)) < UNITS_PER_WORD)
2075 valreg = convert_to_mode (word_mode, valreg,
2076 TREE_UNSIGNED (TREE_TYPE (exp)));
2078 /* Structures whose size is not a multiple of a word are aligned
2079 to the least significant byte (to the right). On a BYTES_BIG_ENDIAN
2080 machine, this means we must skip the empty high order bytes when
2081 calculating the bit offset. */
2082 if (BYTES_BIG_ENDIAN && bytes % UNITS_PER_WORD)
2083 big_endian_correction = (BITS_PER_WORD - ((bytes % UNITS_PER_WORD)
2086 /* Copy the structure BITSIZE bites at a time.
2088 We could probably emit more efficient code for machines
2089 which do not use strict alignment, but it doesn't seem
2090 worth the effort at the current time. */
2091 for (bitpos = 0, xbitpos = big_endian_correction;
2092 bitpos < bytes * BITS_PER_UNIT;
2093 bitpos += bitsize, xbitpos += bitsize)
2096 /* We need a new source operand each time xbitpos is on a
2097 word boundary and when xbitpos == big_endian_correction
2098 (the first time through). */
2099 if (xbitpos % BITS_PER_WORD == 0
2100 || xbitpos == big_endian_correction)
2101 src = operand_subword_force (valreg,
2102 xbitpos / BITS_PER_WORD,
2105 /* We need a new destination operand each time bitpos is on
2107 if (bitpos % BITS_PER_WORD == 0)
2108 dst = operand_subword (target, bitpos / BITS_PER_WORD, 1, BLKmode);
2110 /* Use xbitpos for the source extraction (right justified) and
2111 xbitpos for the destination store (left justified). */
2112 store_bit_field (dst, bitsize, bitpos % BITS_PER_WORD, word_mode,
2113 extract_bit_field (src, bitsize,
2114 xbitpos % BITS_PER_WORD, 1,
2115 NULL_RTX, word_mode,
2117 bitsize / BITS_PER_UNIT,
2119 bitsize / BITS_PER_UNIT, BITS_PER_WORD);
2123 target = copy_to_reg (valreg);
2125 #ifdef PROMOTE_FUNCTION_RETURN
2126 /* If we promoted this return value, make the proper SUBREG. TARGET
2127 might be const0_rtx here, so be careful. */
2128 if (GET_CODE (target) == REG
2129 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
2130 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
2132 tree type = TREE_TYPE (exp);
2133 int unsignedp = TREE_UNSIGNED (type);
2135 /* If we don't promote as expected, something is wrong. */
2136 if (GET_MODE (target)
2137 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
2140 target = gen_rtx (SUBREG, TYPE_MODE (type), target, 0);
2141 SUBREG_PROMOTED_VAR_P (target) = 1;
2142 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
2146 if (flag_short_temps)
2148 /* Perform all cleanups needed for the arguments of this call
2149 (i.e. destructors in C++). */
2150 expand_cleanups_to (old_cleanups);
2153 /* If size of args is variable or this was a constructor call for a stack
2154 argument, restore saved stack-pointer value. */
2156 if (old_stack_level)
2158 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
2159 pending_stack_adjust = old_pending_adj;
2160 #ifdef ACCUMULATE_OUTGOING_ARGS
2161 stack_arg_under_construction = old_stack_arg_under_construction;
2162 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2163 stack_usage_map = initial_stack_usage_map;
2166 #ifdef ACCUMULATE_OUTGOING_ARGS
2169 #ifdef REG_PARM_STACK_SPACE
2172 enum machine_mode save_mode = GET_MODE (save_area);
2174 = gen_rtx (MEM, save_mode,
2175 memory_address (save_mode,
2176 #ifdef ARGS_GROW_DOWNWARD
2177 plus_constant (argblock, - high_to_save)
2179 plus_constant (argblock, low_to_save)
2183 if (save_mode != BLKmode)
2184 emit_move_insn (stack_area, save_area);
2186 emit_block_move (stack_area, validize_mem (save_area),
2187 GEN_INT (high_to_save - low_to_save + 1),
2188 PARM_BOUNDARY / BITS_PER_UNIT);
2192 /* If we saved any argument areas, restore them. */
2193 for (i = 0; i < num_actuals; i++)
2194 if (args[i].save_area)
2196 enum machine_mode save_mode = GET_MODE (args[i].save_area);
2198 = gen_rtx (MEM, save_mode,
2199 memory_address (save_mode,
2200 XEXP (args[i].stack_slot, 0)));
2202 if (save_mode != BLKmode)
2203 emit_move_insn (stack_area, args[i].save_area);
2205 emit_block_move (stack_area, validize_mem (args[i].save_area),
2206 GEN_INT (args[i].size.constant),
2207 PARM_BOUNDARY / BITS_PER_UNIT);
2210 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2211 stack_usage_map = initial_stack_usage_map;
2215 /* If this was alloca, record the new stack level for nonlocal gotos.
2216 Check for the handler slots since we might not have a save area
2217 for non-local gotos. */
2219 if (may_be_alloca && nonlocal_goto_handler_slot != 0)
2220 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
2227 /* Output a library call to function FUN (a SYMBOL_REF rtx)
2228 (emitting the queue unless NO_QUEUE is nonzero),
2229 for a value of mode OUTMODE,
2230 with NARGS different arguments, passed as alternating rtx values
2231 and machine_modes to convert them to.
2232 The rtx values should have been passed through protect_from_queue already.
2234 NO_QUEUE will be true if and only if the library call is a `const' call
2235 which will be enclosed in REG_LIBCALL/REG_RETVAL notes; it is equivalent
2236 to the variable is_const in expand_call.
2238 NO_QUEUE must be true for const calls, because if it isn't, then
2239 any pending increment will be emitted between REG_LIBCALL/REG_RETVAL notes,
2240 and will be lost if the libcall sequence is optimized away.
2242 NO_QUEUE must be false for non-const calls, because if it isn't, the
2243 call insn will have its CONST_CALL_P bit set, and it will be incorrectly
2244 optimized. For instance, the instruction scheduler may incorrectly
2245 move memory references across the non-const call. */
2248 emit_library_call VPROTO((rtx orgfun, int no_queue, enum machine_mode outmode,
2254 enum machine_mode outmode;
2258 /* Total size in bytes of all the stack-parms scanned so far. */
2259 struct args_size args_size;
2260 /* Size of arguments before any adjustments (such as rounding). */
2261 struct args_size original_args_size;
2262 register int argnum;
2267 CUMULATIVE_ARGS args_so_far;
2268 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2269 struct args_size offset; struct args_size size; };
2271 int old_inhibit_defer_pop = inhibit_defer_pop;
2272 rtx call_fusage = 0;
2274 VA_START (p, nargs);
2277 orgfun = va_arg (p, rtx);
2278 no_queue = va_arg (p, int);
2279 outmode = va_arg (p, enum machine_mode);
2280 nargs = va_arg (p, int);
2285 /* Copy all the libcall-arguments out of the varargs data
2286 and into a vector ARGVEC.
2288 Compute how to pass each argument. We only support a very small subset
2289 of the full argument passing conventions to limit complexity here since
2290 library functions shouldn't have many args. */
2292 argvec = (struct arg *) alloca (nargs * sizeof (struct arg));
2294 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
2296 args_size.constant = 0;
2301 for (count = 0; count < nargs; count++)
2303 rtx val = va_arg (p, rtx);
2304 enum machine_mode mode = va_arg (p, enum machine_mode);
2306 /* We cannot convert the arg value to the mode the library wants here;
2307 must do it earlier where we know the signedness of the arg. */
2309 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2312 /* On some machines, there's no way to pass a float to a library fcn.
2313 Pass it as a double instead. */
2314 #ifdef LIBGCC_NEEDS_DOUBLE
2315 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2316 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
2319 /* There's no need to call protect_from_queue, because
2320 either emit_move_insn or emit_push_insn will do that. */
2322 /* Make sure it is a reasonable operand for a move or push insn. */
2323 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2324 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2325 val = force_operand (val, NULL_RTX);
2327 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2328 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2330 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2331 be viewed as just an efficiency improvement. */
2332 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2333 emit_move_insn (slot, val);
2334 val = force_operand (XEXP (slot, 0), NULL_RTX);
2339 argvec[count].value = val;
2340 argvec[count].mode = mode;
2342 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2343 if (argvec[count].reg && GET_CODE (argvec[count].reg) == PARALLEL)
2345 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2346 argvec[count].partial
2347 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2349 argvec[count].partial = 0;
2352 locate_and_pad_parm (mode, NULL_TREE,
2353 argvec[count].reg && argvec[count].partial == 0,
2354 NULL_TREE, &args_size, &argvec[count].offset,
2355 &argvec[count].size);
2357 if (argvec[count].size.var)
2360 #ifndef REG_PARM_STACK_SPACE
2361 if (argvec[count].partial)
2362 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2365 if (argvec[count].reg == 0 || argvec[count].partial != 0
2366 #ifdef REG_PARM_STACK_SPACE
2370 args_size.constant += argvec[count].size.constant;
2372 #ifdef ACCUMULATE_OUTGOING_ARGS
2373 /* If this arg is actually passed on the stack, it might be
2374 clobbering something we already put there (this library call might
2375 be inside the evaluation of an argument to a function whose call
2376 requires the stack). This will only occur when the library call
2377 has sufficient args to run out of argument registers. Abort in
2378 this case; if this ever occurs, code must be added to save and
2379 restore the arg slot. */
2381 if (argvec[count].reg == 0 || argvec[count].partial != 0)
2385 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
2389 /* If this machine requires an external definition for library
2390 functions, write one out. */
2391 assemble_external_libcall (fun);
2393 original_args_size = args_size;
2394 #ifdef STACK_BOUNDARY
2395 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2396 / STACK_BYTES) * STACK_BYTES);
2399 #ifdef REG_PARM_STACK_SPACE
2400 args_size.constant = MAX (args_size.constant,
2401 REG_PARM_STACK_SPACE (NULL_TREE));
2402 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2403 args_size.constant -= REG_PARM_STACK_SPACE (NULL_TREE);
2407 if (args_size.constant > current_function_outgoing_args_size)
2408 current_function_outgoing_args_size = args_size.constant;
2410 #ifdef ACCUMULATE_OUTGOING_ARGS
2411 args_size.constant = 0;
2414 #ifndef PUSH_ROUNDING
2415 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2418 #ifdef PUSH_ARGS_REVERSED
2419 #ifdef STACK_BOUNDARY
2420 /* If we push args individually in reverse order, perform stack alignment
2421 before the first push (the last arg). */
2423 anti_adjust_stack (GEN_INT (args_size.constant
2424 - original_args_size.constant));
2428 #ifdef PUSH_ARGS_REVERSED
2436 /* Push the args that need to be pushed. */
2438 for (count = 0; count < nargs; count++, argnum += inc)
2440 register enum machine_mode mode = argvec[argnum].mode;
2441 register rtx val = argvec[argnum].value;
2442 rtx reg = argvec[argnum].reg;
2443 int partial = argvec[argnum].partial;
2445 if (! (reg != 0 && partial == 0))
2446 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2447 argblock, GEN_INT (argvec[count].offset.constant));
2451 #ifndef PUSH_ARGS_REVERSED
2452 #ifdef STACK_BOUNDARY
2453 /* If we pushed args in forward order, perform stack alignment
2454 after pushing the last arg. */
2456 anti_adjust_stack (GEN_INT (args_size.constant
2457 - original_args_size.constant));
2461 #ifdef PUSH_ARGS_REVERSED
2467 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
2469 /* Now load any reg parms into their regs. */
2471 for (count = 0; count < nargs; count++, argnum += inc)
2473 register enum machine_mode mode = argvec[argnum].mode;
2474 register rtx val = argvec[argnum].value;
2475 rtx reg = argvec[argnum].reg;
2476 int partial = argvec[argnum].partial;
2478 if (reg != 0 && partial == 0)
2479 emit_move_insn (reg, val);
2483 /* For version 1.37, try deleting this entirely. */
2487 /* Any regs containing parms remain in use through the call. */
2488 for (count = 0; count < nargs; count++)
2489 if (argvec[count].reg != 0)
2490 use_reg (&call_fusage, argvec[count].reg);
2492 /* Don't allow popping to be deferred, since then
2493 cse'ing of library calls could delete a call and leave the pop. */
2496 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2497 will set inhibit_defer_pop to that value. */
2500 get_identifier (XSTR (orgfun, 0)),
2501 get_identifier (XSTR (orgfun, 0)), args_size.constant, 0,
2502 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2503 outmode != VOIDmode ? hard_libcall_value (outmode) : NULL_RTX,
2504 old_inhibit_defer_pop + 1, call_fusage, no_queue);
2508 /* Now restore inhibit_defer_pop to its actual original value. */
2512 /* Like emit_library_call except that an extra argument, VALUE,
2513 comes second and says where to store the result.
2514 (If VALUE is zero, this function chooses a convenient way
2515 to return the value.
2517 This function returns an rtx for where the value is to be found.
2518 If VALUE is nonzero, VALUE is returned. */
2521 emit_library_call_value VPROTO((rtx orgfun, rtx value, int no_queue,
2522 enum machine_mode outmode, int nargs, ...))
2528 enum machine_mode outmode;
2532 /* Total size in bytes of all the stack-parms scanned so far. */
2533 struct args_size args_size;
2534 /* Size of arguments before any adjustments (such as rounding). */
2535 struct args_size original_args_size;
2536 register int argnum;
2541 CUMULATIVE_ARGS args_so_far;
2542 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2543 struct args_size offset; struct args_size size; };
2545 int old_inhibit_defer_pop = inhibit_defer_pop;
2546 rtx call_fusage = 0;
2548 int pcc_struct_value = 0;
2549 int struct_value_size = 0;
2552 VA_START (p, nargs);
2555 orgfun = va_arg (p, rtx);
2556 value = va_arg (p, rtx);
2557 no_queue = va_arg (p, int);
2558 outmode = va_arg (p, enum machine_mode);
2559 nargs = va_arg (p, int);
2562 is_const = no_queue;
2565 /* If this kind of value comes back in memory,
2566 decide where in memory it should come back. */
2567 if (aggregate_value_p (type_for_mode (outmode, 0)))
2569 #ifdef PCC_STATIC_STRUCT_RETURN
2571 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
2573 mem_value = gen_rtx (MEM, outmode, pointer_reg);
2574 pcc_struct_value = 1;
2576 value = gen_reg_rtx (outmode);
2577 #else /* not PCC_STATIC_STRUCT_RETURN */
2578 struct_value_size = GET_MODE_SIZE (outmode);
2579 if (value != 0 && GET_CODE (value) == MEM)
2582 mem_value = assign_stack_temp (outmode, GET_MODE_SIZE (outmode), 0);
2585 /* This call returns a big structure. */
2589 /* ??? Unfinished: must pass the memory address as an argument. */
2591 /* Copy all the libcall-arguments out of the varargs data
2592 and into a vector ARGVEC.
2594 Compute how to pass each argument. We only support a very small subset
2595 of the full argument passing conventions to limit complexity here since
2596 library functions shouldn't have many args. */
2598 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
2600 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
2602 args_size.constant = 0;
2609 /* If there's a structure value address to be passed,
2610 either pass it in the special place, or pass it as an extra argument. */
2611 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
2613 rtx addr = XEXP (mem_value, 0);
2616 /* Make sure it is a reasonable operand for a move or push insn. */
2617 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
2618 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
2619 addr = force_operand (addr, NULL_RTX);
2621 argvec[count].value = addr;
2622 argvec[count].mode = Pmode;
2623 argvec[count].partial = 0;
2625 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
2626 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2627 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
2631 locate_and_pad_parm (Pmode, NULL_TREE,
2632 argvec[count].reg && argvec[count].partial == 0,
2633 NULL_TREE, &args_size, &argvec[count].offset,
2634 &argvec[count].size);
2637 if (argvec[count].reg == 0 || argvec[count].partial != 0
2638 #ifdef REG_PARM_STACK_SPACE
2642 args_size.constant += argvec[count].size.constant;
2644 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
2649 for (; count < nargs; count++)
2651 rtx val = va_arg (p, rtx);
2652 enum machine_mode mode = va_arg (p, enum machine_mode);
2654 /* We cannot convert the arg value to the mode the library wants here;
2655 must do it earlier where we know the signedness of the arg. */
2657 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2660 /* On some machines, there's no way to pass a float to a library fcn.
2661 Pass it as a double instead. */
2662 #ifdef LIBGCC_NEEDS_DOUBLE
2663 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2664 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
2667 /* There's no need to call protect_from_queue, because
2668 either emit_move_insn or emit_push_insn will do that. */
2670 /* Make sure it is a reasonable operand for a move or push insn. */
2671 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2672 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2673 val = force_operand (val, NULL_RTX);
2675 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2676 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2678 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2679 be viewed as just an efficiency improvement. */
2680 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2681 emit_move_insn (slot, val);
2682 val = XEXP (slot, 0);
2687 argvec[count].value = val;
2688 argvec[count].mode = mode;
2690 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2691 if (argvec[count].reg && GET_CODE (argvec[count].reg) == PARALLEL)
2693 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2694 argvec[count].partial
2695 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2697 argvec[count].partial = 0;
2700 locate_and_pad_parm (mode, NULL_TREE,
2701 argvec[count].reg && argvec[count].partial == 0,
2702 NULL_TREE, &args_size, &argvec[count].offset,
2703 &argvec[count].size);
2705 if (argvec[count].size.var)
2708 #ifndef REG_PARM_STACK_SPACE
2709 if (argvec[count].partial)
2710 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2713 if (argvec[count].reg == 0 || argvec[count].partial != 0
2714 #ifdef REG_PARM_STACK_SPACE
2718 args_size.constant += argvec[count].size.constant;
2720 #ifdef ACCUMULATE_OUTGOING_ARGS
2721 /* If this arg is actually passed on the stack, it might be
2722 clobbering something we already put there (this library call might
2723 be inside the evaluation of an argument to a function whose call
2724 requires the stack). This will only occur when the library call
2725 has sufficient args to run out of argument registers. Abort in
2726 this case; if this ever occurs, code must be added to save and
2727 restore the arg slot. */
2729 if (argvec[count].reg == 0 || argvec[count].partial != 0)
2733 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
2737 /* If this machine requires an external definition for library
2738 functions, write one out. */
2739 assemble_external_libcall (fun);
2741 original_args_size = args_size;
2742 #ifdef STACK_BOUNDARY
2743 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2744 / STACK_BYTES) * STACK_BYTES);
2747 #ifdef REG_PARM_STACK_SPACE
2748 args_size.constant = MAX (args_size.constant,
2749 REG_PARM_STACK_SPACE (NULL_TREE));
2750 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2751 args_size.constant -= REG_PARM_STACK_SPACE (NULL_TREE);
2755 if (args_size.constant > current_function_outgoing_args_size)
2756 current_function_outgoing_args_size = args_size.constant;
2758 #ifdef ACCUMULATE_OUTGOING_ARGS
2759 args_size.constant = 0;
2762 #ifndef PUSH_ROUNDING
2763 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2766 #ifdef PUSH_ARGS_REVERSED
2767 #ifdef STACK_BOUNDARY
2768 /* If we push args individually in reverse order, perform stack alignment
2769 before the first push (the last arg). */
2771 anti_adjust_stack (GEN_INT (args_size.constant
2772 - original_args_size.constant));
2776 #ifdef PUSH_ARGS_REVERSED
2784 /* Push the args that need to be pushed. */
2786 for (count = 0; count < nargs; count++, argnum += inc)
2788 register enum machine_mode mode = argvec[argnum].mode;
2789 register rtx val = argvec[argnum].value;
2790 rtx reg = argvec[argnum].reg;
2791 int partial = argvec[argnum].partial;
2793 if (! (reg != 0 && partial == 0))
2794 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2795 argblock, GEN_INT (argvec[count].offset.constant));
2799 #ifndef PUSH_ARGS_REVERSED
2800 #ifdef STACK_BOUNDARY
2801 /* If we pushed args in forward order, perform stack alignment
2802 after pushing the last arg. */
2804 anti_adjust_stack (GEN_INT (args_size.constant
2805 - original_args_size.constant));
2809 #ifdef PUSH_ARGS_REVERSED
2815 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
2817 /* Now load any reg parms into their regs. */
2819 for (count = 0; count < nargs; count++, argnum += inc)
2821 register enum machine_mode mode = argvec[argnum].mode;
2822 register rtx val = argvec[argnum].value;
2823 rtx reg = argvec[argnum].reg;
2824 int partial = argvec[argnum].partial;
2826 if (reg != 0 && partial == 0)
2827 emit_move_insn (reg, val);
2832 /* For version 1.37, try deleting this entirely. */
2837 /* Any regs containing parms remain in use through the call. */
2838 for (count = 0; count < nargs; count++)
2839 if (argvec[count].reg != 0)
2840 use_reg (&call_fusage, argvec[count].reg);
2842 /* Pass the function the address in which to return a structure value. */
2843 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
2845 emit_move_insn (struct_value_rtx,
2847 force_operand (XEXP (mem_value, 0),
2849 if (GET_CODE (struct_value_rtx) == REG)
2850 use_reg (&call_fusage, struct_value_rtx);
2853 /* Don't allow popping to be deferred, since then
2854 cse'ing of library calls could delete a call and leave the pop. */
2857 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2858 will set inhibit_defer_pop to that value. */
2861 get_identifier (XSTR (orgfun, 0)),
2862 get_identifier (XSTR (orgfun, 0)), args_size.constant,
2864 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2865 (outmode != VOIDmode && mem_value == 0
2866 ? hard_libcall_value (outmode) : NULL_RTX),
2867 old_inhibit_defer_pop + 1, call_fusage, is_const);
2869 /* Now restore inhibit_defer_pop to its actual original value. */
2874 /* Copy the value to the right place. */
2875 if (outmode != VOIDmode)
2881 if (value != mem_value)
2882 emit_move_insn (value, mem_value);
2884 else if (value != 0)
2885 emit_move_insn (value, hard_libcall_value (outmode));
2887 value = hard_libcall_value (outmode);
2894 /* Return an rtx which represents a suitable home on the stack
2895 given TYPE, the type of the argument looking for a home.
2896 This is called only for BLKmode arguments.
2898 SIZE is the size needed for this target.
2899 ARGS_ADDR is the address of the bottom of the argument block for this call.
2900 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
2901 if this machine uses push insns. */
2904 target_for_arg (type, size, args_addr, offset)
2908 struct args_size offset;
2911 rtx offset_rtx = ARGS_SIZE_RTX (offset);
2913 /* We do not call memory_address if possible,
2914 because we want to address as close to the stack
2915 as possible. For non-variable sized arguments,
2916 this will be stack-pointer relative addressing. */
2917 if (GET_CODE (offset_rtx) == CONST_INT)
2918 target = plus_constant (args_addr, INTVAL (offset_rtx));
2921 /* I have no idea how to guarantee that this
2922 will work in the presence of register parameters. */
2923 target = gen_rtx (PLUS, Pmode, args_addr, offset_rtx);
2924 target = memory_address (QImode, target);
2927 return gen_rtx (MEM, BLKmode, target);
2931 /* Store a single argument for a function call
2932 into the register or memory area where it must be passed.
2933 *ARG describes the argument value and where to pass it.
2935 ARGBLOCK is the address of the stack-block for all the arguments,
2936 or 0 on a machine where arguments are pushed individually.
2938 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
2939 so must be careful about how the stack is used.
2941 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
2942 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
2943 that we need not worry about saving and restoring the stack.
2945 FNDECL is the declaration of the function we are calling. */
2948 store_one_arg (arg, argblock, may_be_alloca, variable_size, fndecl,
2949 reg_parm_stack_space)
2950 struct arg_data *arg;
2955 int reg_parm_stack_space;
2957 register tree pval = arg->tree_value;
2961 int i, lower_bound, upper_bound;
2963 if (TREE_CODE (pval) == ERROR_MARK)
2966 /* Push a new temporary level for any temporaries we make for
2970 #ifdef ACCUMULATE_OUTGOING_ARGS
2971 /* If this is being stored into a pre-allocated, fixed-size, stack area,
2972 save any previous data at that location. */
2973 if (argblock && ! variable_size && arg->stack)
2975 #ifdef ARGS_GROW_DOWNWARD
2976 /* stack_slot is negative, but we want to index stack_usage_map
2977 with positive values. */
2978 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
2979 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
2983 lower_bound = upper_bound - arg->size.constant;
2985 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
2986 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
2990 upper_bound = lower_bound + arg->size.constant;
2993 for (i = lower_bound; i < upper_bound; i++)
2994 if (stack_usage_map[i]
2995 #ifdef REG_PARM_STACK_SPACE
2996 /* Don't store things in the fixed argument area at this point;
2997 it has already been saved. */
2998 && i > reg_parm_stack_space
3003 if (i != upper_bound)
3005 /* We need to make a save area. See what mode we can make it. */
3006 enum machine_mode save_mode
3007 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
3009 = gen_rtx (MEM, save_mode,
3010 memory_address (save_mode, XEXP (arg->stack_slot, 0)));
3012 if (save_mode == BLKmode)
3014 arg->save_area = assign_stack_temp (BLKmode,
3015 arg->size.constant, 0);
3016 MEM_IN_STRUCT_P (arg->save_area)
3017 = AGGREGATE_TYPE_P (TREE_TYPE (arg->tree_value));
3018 preserve_temp_slots (arg->save_area);
3019 emit_block_move (validize_mem (arg->save_area), stack_area,
3020 GEN_INT (arg->size.constant),
3021 PARM_BOUNDARY / BITS_PER_UNIT);
3025 arg->save_area = gen_reg_rtx (save_mode);
3026 emit_move_insn (arg->save_area, stack_area);
3032 /* If this isn't going to be placed on both the stack and in registers,
3033 set up the register and number of words. */
3034 if (! arg->pass_on_stack)
3035 reg = arg->reg, partial = arg->partial;
3037 if (reg != 0 && partial == 0)
3038 /* Being passed entirely in a register. We shouldn't be called in
3042 /* If this arg needs special alignment, don't load the registers
3044 if (arg->n_aligned_regs != 0)
3047 /* If this is being passed partially in a register, we can't evaluate
3048 it directly into its stack slot. Otherwise, we can. */
3049 if (arg->value == 0)
3051 #ifdef ACCUMULATE_OUTGOING_ARGS
3052 /* stack_arg_under_construction is nonzero if a function argument is
3053 being evaluated directly into the outgoing argument list and
3054 expand_call must take special action to preserve the argument list
3055 if it is called recursively.
3057 For scalar function arguments stack_usage_map is sufficient to
3058 determine which stack slots must be saved and restored. Scalar
3059 arguments in general have pass_on_stack == 0.
3061 If this argument is initialized by a function which takes the
3062 address of the argument (a C++ constructor or a C function
3063 returning a BLKmode structure), then stack_usage_map is
3064 insufficient and expand_call must push the stack around the
3065 function call. Such arguments have pass_on_stack == 1.
3067 Note that it is always safe to set stack_arg_under_construction,
3068 but this generates suboptimal code if set when not needed. */
3070 if (arg->pass_on_stack)
3071 stack_arg_under_construction++;
3073 arg->value = expand_expr (pval,
3075 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
3076 ? NULL_RTX : arg->stack,
3079 /* If we are promoting object (or for any other reason) the mode
3080 doesn't agree, convert the mode. */
3082 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
3083 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
3084 arg->value, arg->unsignedp);
3086 #ifdef ACCUMULATE_OUTGOING_ARGS
3087 if (arg->pass_on_stack)
3088 stack_arg_under_construction--;
3092 /* Don't allow anything left on stack from computation
3093 of argument to alloca. */
3095 do_pending_stack_adjust ();
3097 if (arg->value == arg->stack)
3098 /* If the value is already in the stack slot, we are done. */
3100 else if (arg->mode != BLKmode)
3104 /* Argument is a scalar, not entirely passed in registers.
3105 (If part is passed in registers, arg->partial says how much
3106 and emit_push_insn will take care of putting it there.)
3108 Push it, and if its size is less than the
3109 amount of space allocated to it,
3110 also bump stack pointer by the additional space.
3111 Note that in C the default argument promotions
3112 will prevent such mismatches. */
3114 size = GET_MODE_SIZE (arg->mode);
3115 /* Compute how much space the push instruction will push.
3116 On many machines, pushing a byte will advance the stack
3117 pointer by a halfword. */
3118 #ifdef PUSH_ROUNDING
3119 size = PUSH_ROUNDING (size);
3123 /* Compute how much space the argument should get:
3124 round up to a multiple of the alignment for arguments. */
3125 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
3126 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
3127 / (PARM_BOUNDARY / BITS_PER_UNIT))
3128 * (PARM_BOUNDARY / BITS_PER_UNIT));
3130 /* This isn't already where we want it on the stack, so put it there.
3131 This can either be done with push or copy insns. */
3132 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
3133 0, partial, reg, used - size,
3134 argblock, ARGS_SIZE_RTX (arg->offset));
3138 /* BLKmode, at least partly to be pushed. */
3140 register int excess;
3143 /* Pushing a nonscalar.
3144 If part is passed in registers, PARTIAL says how much
3145 and emit_push_insn will take care of putting it there. */
3147 /* Round its size up to a multiple
3148 of the allocation unit for arguments. */
3150 if (arg->size.var != 0)
3153 size_rtx = ARGS_SIZE_RTX (arg->size);
3157 /* PUSH_ROUNDING has no effect on us, because
3158 emit_push_insn for BLKmode is careful to avoid it. */
3159 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
3160 + partial * UNITS_PER_WORD);
3161 size_rtx = expr_size (pval);
3164 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
3165 TYPE_ALIGN (TREE_TYPE (pval)) / BITS_PER_UNIT, partial,
3166 reg, excess, argblock, ARGS_SIZE_RTX (arg->offset));
3170 /* Unless this is a partially-in-register argument, the argument is now
3173 ??? Note that this can change arg->value from arg->stack to
3174 arg->stack_slot and it matters when they are not the same.
3175 It isn't totally clear that this is correct in all cases. */
3177 arg->value = arg->stack_slot;
3179 /* Once we have pushed something, pops can't safely
3180 be deferred during the rest of the arguments. */
3183 /* ANSI doesn't require a sequence point here,
3184 but PCC has one, so this will avoid some problems. */
3187 /* Free any temporary slots made in processing this argument. Show
3188 that we might have taken the address of something and pushed that
3190 preserve_temp_slots (NULL_RTX);
3194 #ifdef ACCUMULATE_OUTGOING_ARGS
3195 /* Now mark the segment we just used. */
3196 if (argblock && ! variable_size && arg->stack)
3197 for (i = lower_bound; i < upper_bound; i++)
3198 stack_usage_map[i] = 1;