1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998
3 1999, 2000 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
30 #include "insn-flags.h"
35 #ifndef ACCUMULATE_OUTGOING_ARGS
36 #define ACCUMULATE_OUTGOING_ARGS 0
39 /* Supply a default definition for PUSH_ARGS. */
42 #define PUSH_ARGS !ACCUMULATE_OUTGOING_ARGS
48 #if !defined FUNCTION_OK_FOR_SIBCALL
49 #define FUNCTION_OK_FOR_SIBCALL(DECL) 1
52 #if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY
53 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
56 /* Decide whether a function's arguments should be processed
57 from first to last or from last to first.
59 They should if the stack and args grow in opposite directions, but
60 only if we have push insns. */
64 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
65 #define PUSH_ARGS_REVERSED PUSH_ARGS
70 #ifndef PUSH_ARGS_REVERSED
71 #define PUSH_ARGS_REVERSED 0
74 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
75 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
77 /* Data structure and subroutines used within expand_call. */
81 /* Tree node for this argument. */
83 /* Mode for value; TYPE_MODE unless promoted. */
84 enum machine_mode mode;
85 /* Current RTL value for argument, or 0 if it isn't precomputed. */
87 /* Initially-compute RTL value for argument; only for const functions. */
89 /* Register to pass this argument in, 0 if passed on stack, or an
90 PARALLEL if the arg is to be copied into multiple non-contiguous
93 /* If REG was promoted from the actual mode of the argument expression,
94 indicates whether the promotion is sign- or zero-extended. */
96 /* Number of registers to use. 0 means put the whole arg in registers.
97 Also 0 if not passed in registers. */
99 /* Non-zero if argument must be passed on stack.
100 Note that some arguments may be passed on the stack
101 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
102 pass_on_stack identifies arguments that *cannot* go in registers. */
104 /* Offset of this argument from beginning of stack-args. */
105 struct args_size offset;
106 /* Similar, but offset to the start of the stack slot. Different from
107 OFFSET if this arg pads downward. */
108 struct args_size slot_offset;
109 /* Size of this argument on the stack, rounded up for any padding it gets,
110 parts of the argument passed in registers do not count.
111 If REG_PARM_STACK_SPACE is defined, then register parms
112 are counted here as well. */
113 struct args_size size;
114 /* Location on the stack at which parameter should be stored. The store
115 has already been done if STACK == VALUE. */
117 /* Location on the stack of the start of this argument slot. This can
118 differ from STACK if this arg pads downward. This location is known
119 to be aligned to FUNCTION_ARG_BOUNDARY. */
121 /* Place that this stack area has been saved, if needed. */
123 /* If an argument's alignment does not permit direct copying into registers,
124 copy in smaller-sized pieces into pseudos. These are stored in a
125 block pointed to by this field. The next field says how many
126 word-sized pseudos we made. */
129 /* The amount that the stack pointer needs to be adjusted to
130 force alignment for the next argument. */
131 struct args_size alignment_pad;
134 /* A vector of one char per byte of stack space. A byte if non-zero if
135 the corresponding stack location has been used.
136 This vector is used to prevent a function call within an argument from
137 clobbering any stack already set up. */
138 static char *stack_usage_map;
140 /* Size of STACK_USAGE_MAP. */
141 static int highest_outgoing_arg_in_use;
143 /* stack_arg_under_construction is nonzero when an argument may be
144 initialized with a constructor call (including a C function that
145 returns a BLKmode struct) and expand_call must take special action
146 to make sure the object being constructed does not overlap the
147 argument list for the constructor call. */
148 int stack_arg_under_construction;
150 static int calls_function PARAMS ((tree, int));
151 static int calls_function_1 PARAMS ((tree, int));
153 #define ECF_IS_CONST 1
154 #define ECF_NOTHROW 2
155 #define ECF_SIBCALL 4
156 static void emit_call_1 PARAMS ((rtx, tree, tree, HOST_WIDE_INT,
157 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
158 rtx, int, rtx, int));
159 static void precompute_register_parameters PARAMS ((int,
162 static void store_one_arg PARAMS ((struct arg_data *, rtx, int, int,
164 static void store_unaligned_arguments_into_pseudos PARAMS ((struct arg_data *,
166 static int finalize_must_preallocate PARAMS ((int, int,
168 struct args_size *));
169 static void precompute_arguments PARAMS ((int, int, int,
171 struct args_size *));
172 static int compute_argument_block_size PARAMS ((int,
175 static void initialize_argument_information PARAMS ((int,
182 static void compute_argument_addresses PARAMS ((struct arg_data *,
184 static rtx rtx_for_function_call PARAMS ((tree, tree));
185 static void load_register_parameters PARAMS ((struct arg_data *,
187 static int libfunc_nothrow PARAMS ((rtx));
188 static rtx emit_library_call_value_1 PARAMS ((int, rtx, rtx, int,
192 #ifdef REG_PARM_STACK_SPACE
193 static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
194 static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
197 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
200 If WHICH is 0, return 1 if EXP contains a call to any function.
201 Actually, we only need return 1 if evaluating EXP would require pushing
202 arguments on the stack, but that is too difficult to compute, so we just
203 assume any function call might require the stack. */
205 static tree calls_function_save_exprs;
208 calls_function (exp, which)
213 calls_function_save_exprs = 0;
214 val = calls_function_1 (exp, which);
215 calls_function_save_exprs = 0;
220 calls_function_1 (exp, which)
225 enum tree_code code = TREE_CODE (exp);
226 int type = TREE_CODE_CLASS (code);
227 int length = tree_code_length[(int) code];
229 /* If this code is language-specific, we don't know what it will do. */
230 if ((int) code >= NUM_TREE_CODES)
233 /* Only expressions and references can contain calls. */
234 if (type != 'e' && type != '<' && type != '1' && type != '2' && type != 'r'
243 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
244 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
247 tree fndecl = TREE_OPERAND (TREE_OPERAND (exp, 0), 0);
249 if ((DECL_BUILT_IN (fndecl)
250 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
251 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_ALLOCA)
252 || (DECL_SAVED_INSNS (fndecl)
253 && DECL_SAVED_INSNS (fndecl)->calls_alloca))
257 /* Third operand is RTL. */
262 if (SAVE_EXPR_RTL (exp) != 0)
264 if (value_member (exp, calls_function_save_exprs))
266 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
267 calls_function_save_exprs);
268 return (TREE_OPERAND (exp, 0) != 0
269 && calls_function_1 (TREE_OPERAND (exp, 0), which));
275 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
276 if (DECL_INITIAL (local) != 0
277 && calls_function_1 (DECL_INITIAL (local), which))
281 register tree subblock;
283 for (subblock = BLOCK_SUBBLOCKS (exp);
285 subblock = TREE_CHAIN (subblock))
286 if (calls_function_1 (subblock, which))
291 case METHOD_CALL_EXPR:
295 case WITH_CLEANUP_EXPR:
306 for (i = 0; i < length; i++)
307 if (TREE_OPERAND (exp, i) != 0
308 && calls_function_1 (TREE_OPERAND (exp, i), which))
314 /* Force FUNEXP into a form suitable for the address of a CALL,
315 and return that as an rtx. Also load the static chain register
316 if FNDECL is a nested function.
318 CALL_FUSAGE points to a variable holding the prospective
319 CALL_INSN_FUNCTION_USAGE information. */
322 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen)
328 rtx static_chain_value = 0;
330 funexp = protect_from_queue (funexp, 0);
333 /* Get possible static chain value for nested function in C. */
334 static_chain_value = lookup_static_chain (fndecl);
336 /* Make a valid memory address and copy constants thru pseudo-regs,
337 but not for a constant address if -fno-function-cse. */
338 if (GET_CODE (funexp) != SYMBOL_REF)
339 /* If we are using registers for parameters, force the
340 function address into a register now. */
341 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
342 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
343 : memory_address (FUNCTION_MODE, funexp));
346 #ifndef NO_FUNCTION_CSE
347 if (optimize && ! flag_no_function_cse)
348 #ifdef NO_RECURSIVE_FUNCTION_CSE
349 if (fndecl != current_function_decl)
351 funexp = force_reg (Pmode, funexp);
355 if (static_chain_value != 0)
357 emit_move_insn (static_chain_rtx, static_chain_value);
359 if (GET_CODE (static_chain_rtx) == REG)
360 use_reg (call_fusage, static_chain_rtx);
366 /* Generate instructions to call function FUNEXP,
367 and optionally pop the results.
368 The CALL_INSN is the first insn generated.
370 FNDECL is the declaration node of the function. This is given to the
371 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
373 FUNTYPE is the data type of the function. This is given to the macro
374 RETURN_POPS_ARGS to determine whether this function pops its own args.
375 We used to allow an identifier for library functions, but that doesn't
376 work when the return type is an aggregate type and the calling convention
377 says that the pointer to this aggregate is to be popped by the callee.
379 STACK_SIZE is the number of bytes of arguments on the stack,
380 ROUNDED_STACK_SIZE is that number rounded up to
381 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
382 both to put into the call insn and to generate explicit popping
385 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
386 It is zero if this call doesn't want a structure value.
388 NEXT_ARG_REG is the rtx that results from executing
389 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
390 just after all the args have had their registers assigned.
391 This could be whatever you like, but normally it is the first
392 arg-register beyond those used for args in this call,
393 or 0 if all the arg-registers are used in this call.
394 It is passed on to `gen_call' so you can put this info in the call insn.
396 VALREG is a hard register in which a value is returned,
397 or 0 if the call does not return a value.
399 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
400 the args to this call were processed.
401 We restore `inhibit_defer_pop' to that value.
403 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
404 denote registers used by the called function.
406 IS_CONST is true if this is a `const' call. */
409 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
410 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
411 call_fusage, ecf_flags)
413 tree fndecl ATTRIBUTE_UNUSED;
414 tree funtype ATTRIBUTE_UNUSED;
415 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
416 HOST_WIDE_INT rounded_stack_size;
417 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
420 int old_inhibit_defer_pop;
424 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
425 #if defined (HAVE_call) && defined (HAVE_call_value)
426 rtx struct_value_size_rtx = GEN_INT (struct_value_size);
429 int already_popped = 0;
430 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
432 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
433 and we don't want to load it into a register as an optimization,
434 because prepare_call_address already did it if it should be done. */
435 if (GET_CODE (funexp) != SYMBOL_REF)
436 funexp = memory_address (FUNCTION_MODE, funexp);
438 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
439 if ((ecf_flags & ECF_SIBCALL)
440 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
441 && (RETURN_POPS_ARGS (fndecl, funtype, stack_size) > 0
444 rtx n_pop = GEN_INT (RETURN_POPS_ARGS (fndecl, funtype, stack_size));
447 /* If this subroutine pops its own args, record that in the call insn
448 if possible, for the sake of frame pointer elimination. */
451 pat = gen_sibcall_value_pop (valreg,
452 gen_rtx_MEM (FUNCTION_MODE, funexp),
453 rounded_stack_size_rtx, next_arg_reg,
456 pat = gen_sibcall_pop (gen_rtx_MEM (FUNCTION_MODE, funexp),
457 rounded_stack_size_rtx, next_arg_reg, n_pop);
459 emit_call_insn (pat);
465 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
466 /* If the target has "call" or "call_value" insns, then prefer them
467 if no arguments are actually popped. If the target does not have
468 "call" or "call_value" insns, then we must use the popping versions
469 even if the call has no arguments to pop. */
470 #if defined (HAVE_call) && defined (HAVE_call_value)
471 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
474 if (HAVE_call_pop && HAVE_call_value_pop)
477 rtx n_pop = GEN_INT (n_popped);
480 /* If this subroutine pops its own args, record that in the call insn
481 if possible, for the sake of frame pointer elimination. */
484 pat = gen_call_value_pop (valreg,
485 gen_rtx_MEM (FUNCTION_MODE, funexp),
486 rounded_stack_size_rtx, next_arg_reg, n_pop);
488 pat = gen_call_pop (gen_rtx_MEM (FUNCTION_MODE, funexp),
489 rounded_stack_size_rtx, next_arg_reg, n_pop);
491 emit_call_insn (pat);
497 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
498 if ((ecf_flags & ECF_SIBCALL)
499 && HAVE_sibcall && HAVE_sibcall_value)
502 emit_call_insn (gen_sibcall_value (valreg,
503 gen_rtx_MEM (FUNCTION_MODE, funexp),
504 rounded_stack_size_rtx,
505 next_arg_reg, NULL_RTX));
507 emit_call_insn (gen_sibcall (gen_rtx_MEM (FUNCTION_MODE, funexp),
508 rounded_stack_size_rtx, next_arg_reg,
509 struct_value_size_rtx));
514 #if defined (HAVE_call) && defined (HAVE_call_value)
515 if (HAVE_call && HAVE_call_value)
518 emit_call_insn (gen_call_value (valreg,
519 gen_rtx_MEM (FUNCTION_MODE, funexp),
520 rounded_stack_size_rtx, next_arg_reg,
523 emit_call_insn (gen_call (gen_rtx_MEM (FUNCTION_MODE, funexp),
524 rounded_stack_size_rtx, next_arg_reg,
525 struct_value_size_rtx));
531 /* Find the CALL insn we just emitted. */
532 for (call_insn = get_last_insn ();
533 call_insn && GET_CODE (call_insn) != CALL_INSN;
534 call_insn = PREV_INSN (call_insn))
540 /* Put the register usage information on the CALL. If there is already
541 some usage information, put ours at the end. */
542 if (CALL_INSN_FUNCTION_USAGE (call_insn))
546 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
547 link = XEXP (link, 1))
550 XEXP (link, 1) = call_fusage;
553 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
555 /* If this is a const call, then set the insn's unchanging bit. */
556 if (ecf_flags & ECF_IS_CONST)
557 CONST_CALL_P (call_insn) = 1;
559 /* If this call can't throw, attach a REG_EH_REGION reg note to that
561 if (ecf_flags & ECF_NOTHROW)
562 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
563 REG_NOTES (call_insn));
565 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
567 /* Restore this now, so that we do defer pops for this call's args
568 if the context of the call as a whole permits. */
569 inhibit_defer_pop = old_inhibit_defer_pop;
574 CALL_INSN_FUNCTION_USAGE (call_insn)
575 = gen_rtx_EXPR_LIST (VOIDmode,
576 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
577 CALL_INSN_FUNCTION_USAGE (call_insn));
578 rounded_stack_size -= n_popped;
579 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
582 if (!ACCUMULATE_OUTGOING_ARGS)
584 /* If returning from the subroutine does not automatically pop the args,
585 we need an instruction to pop them sooner or later.
586 Perhaps do it now; perhaps just record how much space to pop later.
588 If returning from the subroutine does pop the args, indicate that the
589 stack pointer will be changed. */
591 /* The space for the args is no longer waiting for the call; either it
592 was popped by the call, or it'll be popped below. */
593 arg_space_so_far -= rounded_stack_size - n_popped;
595 if (rounded_stack_size != 0)
597 if (flag_defer_pop && inhibit_defer_pop == 0
598 && !(ecf_flags & ECF_IS_CONST))
599 pending_stack_adjust += rounded_stack_size;
601 adjust_stack (rounded_stack_size_rtx);
604 /* When we accumulate outgoing args, we must avoid any stack manipulations.
605 Restore the stack pointer to its original value now. Usually
606 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
607 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
608 popping variants of functions exist as well.
610 ??? We may optimize similar to defer_pop above, but it is
611 probably not worthwhile.
613 ??? It will be worthwhile to enable combine_stack_adjustments even for
616 anti_adjust_stack (GEN_INT (n_popped));
619 /* Determine if the function identified by NAME and FNDECL is one with
620 special properties we wish to know about.
622 For example, if the function might return more than one time (setjmp), then
623 set RETURNS_TWICE to a nonzero value.
625 Similarly set IS_LONGJMP for if the function is in the longjmp family.
627 Set IS_MALLOC for any of the standard memory allocation functions which
628 allocate from the heap.
630 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
631 space from the stack such as alloca. */
634 special_function_p (fndecl, returns_twice, is_longjmp, fork_or_exec,
635 is_malloc, may_be_alloca)
648 /* The function decl may have the `malloc' attribute. */
649 *is_malloc = fndecl && DECL_IS_MALLOC (fndecl);
652 && fndecl && DECL_NAME (fndecl)
653 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
654 /* Exclude functions not at the file scope, or not `extern',
655 since they are not the magic functions we would otherwise
657 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
659 char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
662 /* We assume that alloca will always be called by name. It
663 makes no sense to pass it as a pointer-to-function to
664 anything that does not understand its behavior. */
666 = (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
668 && ! strcmp (name, "alloca"))
669 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
671 && ! strcmp (name, "__builtin_alloca"))));
673 /* Disregard prefix _, __ or __x. */
676 if (name[1] == '_' && name[2] == 'x')
678 else if (name[1] == '_')
688 && (! strcmp (tname, "setjmp")
689 || ! strcmp (tname, "setjmp_syscall")))
691 && ! strcmp (tname, "sigsetjmp"))
693 && ! strcmp (tname, "savectx")));
695 && ! strcmp (tname, "siglongjmp"))
698 else if ((tname[0] == 'q' && tname[1] == 's'
699 && ! strcmp (tname, "qsetjmp"))
700 || (tname[0] == 'v' && tname[1] == 'f'
701 && ! strcmp (tname, "vfork")))
704 else if (tname[0] == 'l' && tname[1] == 'o'
705 && ! strcmp (tname, "longjmp"))
708 else if ((tname[0] == 'f' && tname[1] == 'o'
709 && ! strcmp (tname, "fork"))
710 /* Linux specific: __clone. check NAME to insist on the
711 leading underscores, to avoid polluting the ISO / POSIX
713 || (name[0] == '_' && name[1] == '_'
714 && ! strcmp (tname, "clone"))
715 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
716 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
718 || ((tname[5] == 'p' || tname[5] == 'e')
719 && tname[6] == '\0'))))
722 /* Do not add any more malloc-like functions to this list,
723 instead mark them as malloc functions using the malloc attribute.
724 Note, realloc is not suitable for attribute malloc since
725 it may return the same address across multiple calls.
726 C++ operator new is not suitable because it is not required
727 to return a unique pointer; indeed, the standard placement new
728 just returns its argument. */
729 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl))) == Pmode
730 && (! strcmp (tname, "malloc")
731 || ! strcmp (tname, "calloc")
732 || ! strcmp (tname, "strdup")))
737 /* Precompute all register parameters as described by ARGS, storing values
738 into fields within the ARGS array.
740 NUM_ACTUALS indicates the total number elements in the ARGS array.
742 Set REG_PARM_SEEN if we encounter a register parameter. */
745 precompute_register_parameters (num_actuals, args, reg_parm_seen)
747 struct arg_data *args;
754 for (i = 0; i < num_actuals; i++)
755 if (args[i].reg != 0 && ! args[i].pass_on_stack)
759 if (args[i].value == 0)
762 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
764 preserve_temp_slots (args[i].value);
767 /* ANSI doesn't require a sequence point here,
768 but PCC has one, so this will avoid some problems. */
772 /* If we are to promote the function arg to a wider mode,
775 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
777 = convert_modes (args[i].mode,
778 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
779 args[i].value, args[i].unsignedp);
781 /* If the value is expensive, and we are inside an appropriately
782 short loop, put the value into a pseudo and then put the pseudo
785 For small register classes, also do this if this call uses
786 register parameters. This is to avoid reload conflicts while
787 loading the parameters registers. */
789 if ((! (GET_CODE (args[i].value) == REG
790 || (GET_CODE (args[i].value) == SUBREG
791 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
792 && args[i].mode != BLKmode
793 && rtx_cost (args[i].value, SET) > 2
794 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
795 || preserve_subexpressions_p ()))
796 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
800 #ifdef REG_PARM_STACK_SPACE
802 /* The argument list is the property of the called routine and it
803 may clobber it. If the fixed area has been used for previous
804 parameters, we must save and restore it. */
806 save_fixed_argument_area (reg_parm_stack_space, argblock,
807 low_to_save, high_to_save)
808 int reg_parm_stack_space;
814 rtx save_area = NULL_RTX;
816 /* Compute the boundary of the that needs to be saved, if any. */
817 #ifdef ARGS_GROW_DOWNWARD
818 for (i = 0; i < reg_parm_stack_space + 1; i++)
820 for (i = 0; i < reg_parm_stack_space; i++)
823 if (i >= highest_outgoing_arg_in_use
824 || stack_usage_map[i] == 0)
827 if (*low_to_save == -1)
833 if (*low_to_save >= 0)
835 int num_to_save = *high_to_save - *low_to_save + 1;
836 enum machine_mode save_mode
837 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
840 /* If we don't have the required alignment, must do this in BLKmode. */
841 if ((*low_to_save & (MIN (GET_MODE_SIZE (save_mode),
842 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
845 #ifdef ARGS_GROW_DOWNWARD
846 stack_area = gen_rtx_MEM (save_mode,
847 memory_address (save_mode,
848 plus_constant (argblock,
851 stack_area = gen_rtx_MEM (save_mode,
852 memory_address (save_mode,
853 plus_constant (argblock,
856 if (save_mode == BLKmode)
858 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
859 /* Cannot use emit_block_move here because it can be done by a
860 library call which in turn gets into this place again and deadly
861 infinite recursion happens. */
862 move_by_pieces (validize_mem (save_area), stack_area, num_to_save,
867 save_area = gen_reg_rtx (save_mode);
868 emit_move_insn (save_area, stack_area);
875 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
881 enum machine_mode save_mode = GET_MODE (save_area);
882 #ifdef ARGS_GROW_DOWNWARD
884 = gen_rtx_MEM (save_mode,
885 memory_address (save_mode,
886 plus_constant (argblock,
890 = gen_rtx_MEM (save_mode,
891 memory_address (save_mode,
892 plus_constant (argblock,
896 if (save_mode != BLKmode)
897 emit_move_insn (stack_area, save_area);
899 /* Cannot use emit_block_move here because it can be done by a library
900 call which in turn gets into this place again and deadly infinite
901 recursion happens. */
902 move_by_pieces (stack_area, validize_mem (save_area),
903 high_to_save - low_to_save + 1, PARM_BOUNDARY);
907 /* If any elements in ARGS refer to parameters that are to be passed in
908 registers, but not in memory, and whose alignment does not permit a
909 direct copy into registers. Copy the values into a group of pseudos
910 which we will later copy into the appropriate hard registers.
912 Pseudos for each unaligned argument will be stored into the array
913 args[argnum].aligned_regs. The caller is responsible for deallocating
914 the aligned_regs array if it is nonzero. */
917 store_unaligned_arguments_into_pseudos (args, num_actuals)
918 struct arg_data *args;
923 for (i = 0; i < num_actuals; i++)
924 if (args[i].reg != 0 && ! args[i].pass_on_stack
925 && args[i].mode == BLKmode
926 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
927 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
929 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
930 int big_endian_correction = 0;
932 args[i].n_aligned_regs
933 = args[i].partial ? args[i].partial
934 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
936 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
937 * args[i].n_aligned_regs);
939 /* Structures smaller than a word are aligned to the least
940 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
941 this means we must skip the empty high order bytes when
942 calculating the bit offset. */
943 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
944 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
946 for (j = 0; j < args[i].n_aligned_regs; j++)
948 rtx reg = gen_reg_rtx (word_mode);
949 rtx word = operand_subword_force (args[i].value, j, BLKmode);
950 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
951 int bitalign = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
953 args[i].aligned_regs[j] = reg;
955 /* There is no need to restrict this code to loading items
956 in TYPE_ALIGN sized hunks. The bitfield instructions can
957 load up entire word sized registers efficiently.
959 ??? This may not be needed anymore.
960 We use to emit a clobber here but that doesn't let later
961 passes optimize the instructions we emit. By storing 0 into
962 the register later passes know the first AND to zero out the
963 bitfield being set in the register is unnecessary. The store
964 of 0 will be deleted as will at least the first AND. */
966 emit_move_insn (reg, const0_rtx);
968 bytes -= bitsize / BITS_PER_UNIT;
969 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
970 extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
971 word_mode, word_mode, bitalign,
973 bitalign, BITS_PER_WORD);
978 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
981 NUM_ACTUALS is the total number of parameters.
983 N_NAMED_ARGS is the total number of named arguments.
985 FNDECL is the tree code for the target of this call (if known)
987 ARGS_SO_FAR holds state needed by the target to know where to place
990 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
991 for arguments which are passed in registers.
993 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
994 and may be modified by this routine.
996 OLD_PENDING_ADJ, MUST_PREALLOCATE and IS_CONST are pointers to integer
997 flags which may may be modified by this routine. */
1000 initialize_argument_information (num_actuals, args, args_size, n_named_args,
1001 actparms, fndecl, args_so_far,
1002 reg_parm_stack_space, old_stack_level,
1003 old_pending_adj, must_preallocate, is_const,
1005 int num_actuals ATTRIBUTE_UNUSED;
1006 struct arg_data *args;
1007 struct args_size *args_size;
1008 int n_named_args ATTRIBUTE_UNUSED;
1011 CUMULATIVE_ARGS *args_so_far;
1012 int reg_parm_stack_space;
1013 rtx *old_stack_level;
1014 int *old_pending_adj;
1015 int *must_preallocate;
1017 int ecf_flags ATTRIBUTE_UNUSED;
1019 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1022 /* Count arg position in order args appear. */
1025 struct args_size alignment_pad;
1029 args_size->constant = 0;
1032 /* In this loop, we consider args in the order they are written.
1033 We fill up ARGS from the front or from the back if necessary
1034 so that in any case the first arg to be pushed ends up at the front. */
1036 if (PUSH_ARGS_REVERSED)
1038 i = num_actuals - 1, inc = -1;
1039 /* In this case, must reverse order of args
1040 so that we compute and push the last arg first. */
1047 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1048 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1050 tree type = TREE_TYPE (TREE_VALUE (p));
1052 enum machine_mode mode;
1054 args[i].tree_value = TREE_VALUE (p);
1056 /* Replace erroneous argument with constant zero. */
1057 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1058 args[i].tree_value = integer_zero_node, type = integer_type_node;
1060 /* If TYPE is a transparent union, pass things the way we would
1061 pass the first field of the union. We have already verified that
1062 the modes are the same. */
1063 if (TYPE_TRANSPARENT_UNION (type))
1064 type = TREE_TYPE (TYPE_FIELDS (type));
1066 /* Decide where to pass this arg.
1068 args[i].reg is nonzero if all or part is passed in registers.
1070 args[i].partial is nonzero if part but not all is passed in registers,
1071 and the exact value says how many words are passed in registers.
1073 args[i].pass_on_stack is nonzero if the argument must at least be
1074 computed on the stack. It may then be loaded back into registers
1075 if args[i].reg is nonzero.
1077 These decisions are driven by the FUNCTION_... macros and must agree
1078 with those made by function.c. */
1080 /* See if this argument should be passed by invisible reference. */
1081 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1082 && contains_placeholder_p (TYPE_SIZE (type)))
1083 || TREE_ADDRESSABLE (type)
1084 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1085 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1086 type, argpos < n_named_args)
1090 /* If we're compiling a thunk, pass through invisible
1091 references instead of making a copy. */
1092 if (current_function_is_thunk
1093 #ifdef FUNCTION_ARG_CALLEE_COPIES
1094 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1095 type, argpos < n_named_args)
1096 /* If it's in a register, we must make a copy of it too. */
1097 /* ??? Is this a sufficient test? Is there a better one? */
1098 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1099 && REG_P (DECL_RTL (args[i].tree_value)))
1100 && ! TREE_ADDRESSABLE (type))
1104 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1105 new object from the argument. If we are passing by
1106 invisible reference, the callee will do that for us, so we
1107 can strip off the TARGET_EXPR. This is not always safe,
1108 but it is safe in the only case where this is a useful
1109 optimization; namely, when the argument is a plain object.
1110 In that case, the frontend is just asking the backend to
1111 make a bitwise copy of the argument. */
1113 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1114 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1115 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1116 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1118 args[i].tree_value = build1 (ADDR_EXPR,
1119 build_pointer_type (type),
1120 args[i].tree_value);
1121 type = build_pointer_type (type);
1125 /* We make a copy of the object and pass the address to the
1126 function being called. */
1129 if (!COMPLETE_TYPE_P (type)
1130 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1131 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1132 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1133 STACK_CHECK_MAX_VAR_SIZE))))
1135 /* This is a variable-sized object. Make space on the stack
1137 rtx size_rtx = expr_size (TREE_VALUE (p));
1139 if (*old_stack_level == 0)
1141 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1142 *old_pending_adj = pending_stack_adjust;
1143 pending_stack_adjust = 0;
1146 copy = gen_rtx_MEM (BLKmode,
1147 allocate_dynamic_stack_space (size_rtx,
1149 TYPE_ALIGN (type)));
1153 int size = int_size_in_bytes (type);
1154 copy = assign_stack_temp (TYPE_MODE (type), size, 0);
1157 MEM_SET_IN_STRUCT_P (copy, AGGREGATE_TYPE_P (type));
1159 store_expr (args[i].tree_value, copy, 0);
1162 args[i].tree_value = build1 (ADDR_EXPR,
1163 build_pointer_type (type),
1164 make_tree (type, copy));
1165 type = build_pointer_type (type);
1169 mode = TYPE_MODE (type);
1170 unsignedp = TREE_UNSIGNED (type);
1172 #ifdef PROMOTE_FUNCTION_ARGS
1173 mode = promote_mode (type, mode, &unsignedp, 1);
1176 args[i].unsignedp = unsignedp;
1177 args[i].mode = mode;
1179 #ifdef FUNCTION_INCOMING_ARG
1180 /* If this is a sibling call and the machine has register windows, the
1181 register window has to be unwinded before calling the routine, so
1182 arguments have to go into the incoming registers. */
1183 if (ecf_flags & ECF_SIBCALL)
1184 args[i].reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1185 argpos < n_named_args);
1188 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1189 argpos < n_named_args);
1191 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1194 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1195 argpos < n_named_args);
1198 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1200 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1201 it means that we are to pass this arg in the register(s) designated
1202 by the PARALLEL, but also to pass it in the stack. */
1203 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1204 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1205 args[i].pass_on_stack = 1;
1207 /* If this is an addressable type, we must preallocate the stack
1208 since we must evaluate the object into its final location.
1210 If this is to be passed in both registers and the stack, it is simpler
1212 if (TREE_ADDRESSABLE (type)
1213 || (args[i].pass_on_stack && args[i].reg != 0))
1214 *must_preallocate = 1;
1216 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1217 we cannot consider this function call constant. */
1218 if (TREE_ADDRESSABLE (type))
1221 /* Compute the stack-size of this argument. */
1222 if (args[i].reg == 0 || args[i].partial != 0
1223 || reg_parm_stack_space > 0
1224 || args[i].pass_on_stack)
1225 locate_and_pad_parm (mode, type,
1226 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1231 fndecl, args_size, &args[i].offset,
1232 &args[i].size, &alignment_pad);
1234 #ifndef ARGS_GROW_DOWNWARD
1235 args[i].slot_offset = *args_size;
1238 args[i].alignment_pad = alignment_pad;
1240 /* If a part of the arg was put into registers,
1241 don't include that part in the amount pushed. */
1242 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1243 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1244 / (PARM_BOUNDARY / BITS_PER_UNIT)
1245 * (PARM_BOUNDARY / BITS_PER_UNIT));
1247 /* Update ARGS_SIZE, the total stack space for args so far. */
1249 args_size->constant += args[i].size.constant;
1250 if (args[i].size.var)
1252 ADD_PARM_SIZE (*args_size, args[i].size.var);
1255 /* Since the slot offset points to the bottom of the slot,
1256 we must record it after incrementing if the args grow down. */
1257 #ifdef ARGS_GROW_DOWNWARD
1258 args[i].slot_offset = *args_size;
1260 args[i].slot_offset.constant = -args_size->constant;
1262 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1265 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1266 have been used, etc. */
1268 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1269 argpos < n_named_args);
1273 /* Update ARGS_SIZE to contain the total size for the argument block.
1274 Return the original constant component of the argument block's size.
1276 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1277 for arguments passed in registers. */
1280 compute_argument_block_size (reg_parm_stack_space, args_size,
1281 preferred_stack_boundary)
1282 int reg_parm_stack_space;
1283 struct args_size *args_size;
1284 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1286 int unadjusted_args_size = args_size->constant;
1288 /* For accumulate outgoing args mode we don't need to align, since the frame
1289 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1290 backends from generating missaligned frame sizes. */
1291 #ifdef STACK_BOUNDARY
1292 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1293 preferred_stack_boundary = STACK_BOUNDARY;
1296 /* Compute the actual size of the argument block required. The variable
1297 and constant sizes must be combined, the size may have to be rounded,
1298 and there may be a minimum required size. */
1302 args_size->var = ARGS_SIZE_TREE (*args_size);
1303 args_size->constant = 0;
1305 #ifdef PREFERRED_STACK_BOUNDARY
1306 preferred_stack_boundary /= BITS_PER_UNIT;
1307 if (preferred_stack_boundary > 1)
1308 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1311 if (reg_parm_stack_space > 0)
1314 = size_binop (MAX_EXPR, args_size->var,
1315 ssize_int (reg_parm_stack_space));
1317 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1318 /* The area corresponding to register parameters is not to count in
1319 the size of the block we need. So make the adjustment. */
1321 = size_binop (MINUS_EXPR, args_size->var,
1322 ssize_int (reg_parm_stack_space));
1328 #ifdef PREFERRED_STACK_BOUNDARY
1329 preferred_stack_boundary /= BITS_PER_UNIT;
1330 if (preferred_stack_boundary < 1)
1331 preferred_stack_boundary = 1;
1332 args_size->constant = (((args_size->constant
1334 + pending_stack_adjust
1335 + preferred_stack_boundary - 1)
1336 / preferred_stack_boundary
1337 * preferred_stack_boundary)
1339 - pending_stack_adjust);
1342 args_size->constant = MAX (args_size->constant,
1343 reg_parm_stack_space);
1345 #ifdef MAYBE_REG_PARM_STACK_SPACE
1346 if (reg_parm_stack_space == 0)
1347 args_size->constant = 0;
1350 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1351 args_size->constant -= reg_parm_stack_space;
1354 return unadjusted_args_size;
1357 /* Precompute parameters as needed for a function call.
1359 IS_CONST indicates the target function is a pure function.
1361 MUST_PREALLOCATE indicates that we must preallocate stack space for
1362 any stack arguments.
1364 NUM_ACTUALS is the number of arguments.
1366 ARGS is an array containing information for each argument; this routine
1367 fills in the INITIAL_VALUE and VALUE fields for each precomputed argument.
1369 ARGS_SIZE contains information about the size of the arg list. */
1372 precompute_arguments (is_const, must_preallocate, num_actuals, args, args_size)
1374 int must_preallocate;
1376 struct arg_data *args;
1377 struct args_size *args_size;
1381 /* If this function call is cse'able, precompute all the parameters.
1382 Note that if the parameter is constructed into a temporary, this will
1383 cause an additional copy because the parameter will be constructed
1384 into a temporary location and then copied into the outgoing arguments.
1385 If a parameter contains a call to alloca and this function uses the
1386 stack, precompute the parameter. */
1388 /* If we preallocated the stack space, and some arguments must be passed
1389 on the stack, then we must precompute any parameter which contains a
1390 function call which will store arguments on the stack.
1391 Otherwise, evaluating the parameter may clobber previous parameters
1392 which have already been stored into the stack. */
1394 for (i = 0; i < num_actuals; i++)
1396 || ((args_size->var != 0 || args_size->constant != 0)
1397 && calls_function (args[i].tree_value, 1))
1398 || (must_preallocate
1399 && (args_size->var != 0 || args_size->constant != 0)
1400 && calls_function (args[i].tree_value, 0)))
1402 /* If this is an addressable type, we cannot pre-evaluate it. */
1403 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1409 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1411 preserve_temp_slots (args[i].value);
1414 /* ANSI doesn't require a sequence point here,
1415 but PCC has one, so this will avoid some problems. */
1418 args[i].initial_value = args[i].value
1419 = protect_from_queue (args[i].value, 0);
1421 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) != args[i].mode)
1424 = convert_modes (args[i].mode,
1425 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1426 args[i].value, args[i].unsignedp);
1427 #ifdef PROMOTE_FOR_CALL_ONLY
1428 /* CSE will replace this only if it contains args[i].value
1429 pseudo, so convert it down to the declared mode using
1431 if (GET_CODE (args[i].value) == REG
1432 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1434 args[i].initial_value
1435 = gen_rtx_SUBREG (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1437 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1438 SUBREG_PROMOTED_UNSIGNED_P (args[i].initial_value)
1439 = args[i].unsignedp;
1446 /* Given the current state of MUST_PREALLOCATE and information about
1447 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1448 compute and return the final value for MUST_PREALLOCATE. */
1451 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1452 int must_preallocate;
1454 struct arg_data *args;
1455 struct args_size *args_size;
1457 /* See if we have or want to preallocate stack space.
1459 If we would have to push a partially-in-regs parm
1460 before other stack parms, preallocate stack space instead.
1462 If the size of some parm is not a multiple of the required stack
1463 alignment, we must preallocate.
1465 If the total size of arguments that would otherwise create a copy in
1466 a temporary (such as a CALL) is more than half the total argument list
1467 size, preallocation is faster.
1469 Another reason to preallocate is if we have a machine (like the m88k)
1470 where stack alignment is required to be maintained between every
1471 pair of insns, not just when the call is made. However, we assume here
1472 that such machines either do not have push insns (and hence preallocation
1473 would occur anyway) or the problem is taken care of with
1476 if (! must_preallocate)
1478 int partial_seen = 0;
1479 int copy_to_evaluate_size = 0;
1482 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1484 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1486 else if (partial_seen && args[i].reg == 0)
1487 must_preallocate = 1;
1489 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1490 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1491 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1492 || TREE_CODE (args[i].tree_value) == COND_EXPR
1493 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1494 copy_to_evaluate_size
1495 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1498 if (copy_to_evaluate_size * 2 >= args_size->constant
1499 && args_size->constant > 0)
1500 must_preallocate = 1;
1502 return must_preallocate;
1505 /* If we preallocated stack space, compute the address of each argument
1506 and store it into the ARGS array.
1508 We need not ensure it is a valid memory address here; it will be
1509 validized when it is used.
1511 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1514 compute_argument_addresses (args, argblock, num_actuals)
1515 struct arg_data *args;
1521 rtx arg_reg = argblock;
1522 int i, arg_offset = 0;
1524 if (GET_CODE (argblock) == PLUS)
1525 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1527 for (i = 0; i < num_actuals; i++)
1529 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1530 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1533 /* Skip this parm if it will not be passed on the stack. */
1534 if (! args[i].pass_on_stack && args[i].reg != 0)
1537 if (GET_CODE (offset) == CONST_INT)
1538 addr = plus_constant (arg_reg, INTVAL (offset));
1540 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1542 addr = plus_constant (addr, arg_offset);
1543 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1546 AGGREGATE_TYPE_P (TREE_TYPE (args[i].tree_value)));
1548 if (GET_CODE (slot_offset) == CONST_INT)
1549 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1551 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1553 addr = plus_constant (addr, arg_offset);
1554 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1559 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1560 in a call instruction.
1562 FNDECL is the tree node for the target function. For an indirect call
1563 FNDECL will be NULL_TREE.
1565 EXP is the CALL_EXPR for this call. */
1568 rtx_for_function_call (fndecl, exp)
1574 /* Get the function to call, in the form of RTL. */
1577 /* If this is the first use of the function, see if we need to
1578 make an external definition for it. */
1579 if (! TREE_USED (fndecl))
1581 assemble_external (fndecl);
1582 TREE_USED (fndecl) = 1;
1585 /* Get a SYMBOL_REF rtx for the function address. */
1586 funexp = XEXP (DECL_RTL (fndecl), 0);
1589 /* Generate an rtx (probably a pseudo-register) for the address. */
1594 expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1595 pop_temp_slots (); /* FUNEXP can't be BLKmode */
1597 /* Check the function is executable. */
1598 if (current_function_check_memory_usage)
1600 #ifdef POINTERS_EXTEND_UNSIGNED
1601 /* It might be OK to convert funexp in place, but there's
1602 a lot going on between here and when it happens naturally
1603 that this seems safer. */
1604 funaddr = convert_memory_address (Pmode, funexp);
1606 emit_library_call (chkr_check_exec_libfunc, 1,
1615 /* Do the register loads required for any wholly-register parms or any
1616 parms which are passed both on the stack and in a register. Their
1617 expressions were already evaluated.
1619 Mark all register-parms as living through the call, putting these USE
1620 insns in the CALL_INSN_FUNCTION_USAGE field. */
1623 load_register_parameters (args, num_actuals, call_fusage)
1624 struct arg_data *args;
1630 #ifdef LOAD_ARGS_REVERSED
1631 for (i = num_actuals - 1; i >= 0; i--)
1633 for (i = 0; i < num_actuals; i++)
1636 rtx reg = args[i].reg;
1637 int partial = args[i].partial;
1642 /* Set to non-negative if must move a word at a time, even if just
1643 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1644 we just use a normal move insn. This value can be zero if the
1645 argument is a zero size structure with no fields. */
1646 nregs = (partial ? partial
1647 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1648 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1649 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1652 /* Handle calls that pass values in multiple non-contiguous
1653 locations. The Irix 6 ABI has examples of this. */
1655 if (GET_CODE (reg) == PARALLEL)
1656 emit_group_load (reg, args[i].value,
1657 int_size_in_bytes (TREE_TYPE (args[i].tree_value)),
1658 TYPE_ALIGN (TREE_TYPE (args[i].tree_value)));
1660 /* If simple case, just do move. If normal partial, store_one_arg
1661 has already loaded the register for us. In all other cases,
1662 load the register(s) from memory. */
1664 else if (nregs == -1)
1665 emit_move_insn (reg, args[i].value);
1667 /* If we have pre-computed the values to put in the registers in
1668 the case of non-aligned structures, copy them in now. */
1670 else if (args[i].n_aligned_regs != 0)
1671 for (j = 0; j < args[i].n_aligned_regs; j++)
1672 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1673 args[i].aligned_regs[j]);
1675 else if (partial == 0 || args[i].pass_on_stack)
1676 move_block_to_reg (REGNO (reg),
1677 validize_mem (args[i].value), nregs,
1680 /* Handle calls that pass values in multiple non-contiguous
1681 locations. The Irix 6 ABI has examples of this. */
1682 if (GET_CODE (reg) == PARALLEL)
1683 use_group_regs (call_fusage, reg);
1684 else if (nregs == -1)
1685 use_reg (call_fusage, reg);
1687 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1692 /* Generate all the code for a function call
1693 and return an rtx for its value.
1694 Store the value in TARGET (specified as an rtx) if convenient.
1695 If the value is stored in TARGET then TARGET is returned.
1696 If IGNORE is nonzero, then we ignore the value of the function call. */
1699 expand_call (exp, target, ignore)
1704 /* Nonzero if we are currently expanding a call. */
1705 static int currently_expanding_call = 0;
1707 /* List of actual parameters. */
1708 tree actparms = TREE_OPERAND (exp, 1);
1709 /* RTX for the function to be called. */
1711 /* Sequence of insns to perform a tail recursive "call". */
1712 rtx tail_recursion_insns = NULL_RTX;
1713 /* Sequence of insns to perform a normal "call". */
1714 rtx normal_call_insns = NULL_RTX;
1715 /* Sequence of insns to perform a tail recursive "call". */
1716 rtx tail_call_insns = NULL_RTX;
1717 /* Data type of the function. */
1719 /* Declaration of the function being called,
1720 or 0 if the function is computed (not known by name). */
1728 /* Register in which non-BLKmode value will be returned,
1729 or 0 if no value or if value is BLKmode. */
1731 /* Address where we should return a BLKmode value;
1732 0 if value not BLKmode. */
1733 rtx structure_value_addr = 0;
1734 /* Nonzero if that address is being passed by treating it as
1735 an extra, implicit first parameter. Otherwise,
1736 it is passed by being copied directly into struct_value_rtx. */
1737 int structure_value_addr_parm = 0;
1738 /* Size of aggregate value wanted, or zero if none wanted
1739 or if we are using the non-reentrant PCC calling convention
1740 or expecting the value in registers. */
1741 HOST_WIDE_INT struct_value_size = 0;
1742 /* Nonzero if called function returns an aggregate in memory PCC style,
1743 by returning the address of where to find it. */
1744 int pcc_struct_value = 0;
1746 /* Number of actual parameters in this call, including struct value addr. */
1748 /* Number of named args. Args after this are anonymous ones
1749 and they must all go on the stack. */
1752 /* Vector of information about each argument.
1753 Arguments are numbered in the order they will be pushed,
1754 not the order they are written. */
1755 struct arg_data *args;
1757 /* Total size in bytes of all the stack-parms scanned so far. */
1758 struct args_size args_size;
1759 /* Size of arguments before any adjustments (such as rounding). */
1760 int unadjusted_args_size;
1761 /* Data on reg parms scanned so far. */
1762 CUMULATIVE_ARGS args_so_far;
1763 /* Nonzero if a reg parm has been scanned. */
1765 /* Nonzero if this is an indirect function call. */
1767 /* Nonzero if we must avoid push-insns in the args for this call.
1768 If stack space is allocated for register parameters, but not by the
1769 caller, then it is preallocated in the fixed part of the stack frame.
1770 So the entire argument block must then be preallocated (i.e., we
1771 ignore PUSH_ROUNDING in that case). */
1773 int must_preallocate = !PUSH_ARGS;
1775 /* Size of the stack reserved for parameter registers. */
1776 int reg_parm_stack_space = 0;
1778 /* Address of space preallocated for stack parms
1779 (on machines that lack push insns), or 0 if space not preallocated. */
1782 /* Nonzero if it is plausible that this is a call to alloca. */
1784 /* Nonzero if this is a call to malloc or a related function. */
1786 /* Nonzero if this is a call to setjmp or a related function. */
1788 /* Nonzero if this is a call to `longjmp'. */
1790 /* Nonzero if this is a syscall that makes a new process in the image of
1793 /* Nonzero if this is a call to an inline function. */
1794 int is_integrable = 0;
1795 /* Nonzero if this is a call to a `const' function.
1796 Note that only explicitly named functions are handled as `const' here. */
1798 /* Nonzero if this is a call to a `volatile' function. */
1799 int is_volatile = 0;
1800 /* Nonzero if this is a call to a function that won't throw an exception. */
1801 int nothrow = TREE_NOTHROW (exp);
1802 #ifdef REG_PARM_STACK_SPACE
1803 /* Define the boundary of the register parm stack space that needs to be
1805 int low_to_save = -1, high_to_save;
1806 rtx save_area = 0; /* Place that it is saved */
1809 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
1810 char *initial_stack_usage_map = stack_usage_map;
1811 int old_stack_arg_under_construction = 0;
1813 rtx old_stack_level = 0;
1814 int old_pending_adj = 0;
1815 int old_inhibit_defer_pop = inhibit_defer_pop;
1819 int preferred_stack_boundary;
1821 /* The value of the function call can be put in a hard register. But
1822 if -fcheck-memory-usage, code which invokes functions (and thus
1823 damages some hard registers) can be inserted before using the value.
1824 So, target is always a pseudo-register in that case. */
1825 if (current_function_check_memory_usage)
1828 /* See if we can find a DECL-node for the actual function.
1829 As a result, decide whether this is a call to an integrable function. */
1831 p = TREE_OPERAND (exp, 0);
1832 if (TREE_CODE (p) == ADDR_EXPR)
1834 fndecl = TREE_OPERAND (p, 0);
1835 if (TREE_CODE (fndecl) != FUNCTION_DECL)
1840 && fndecl != current_function_decl
1841 && DECL_INLINE (fndecl)
1842 && DECL_SAVED_INSNS (fndecl)
1843 && DECL_SAVED_INSNS (fndecl)->inlinable)
1845 else if (! TREE_ADDRESSABLE (fndecl))
1847 /* In case this function later becomes inlinable,
1848 record that there was already a non-inline call to it.
1850 Use abstraction instead of setting TREE_ADDRESSABLE
1852 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1855 warning_with_decl (fndecl, "can't inline call to `%s'");
1856 warning ("called from here");
1858 mark_addressable (fndecl);
1861 if (TREE_READONLY (fndecl) && ! TREE_THIS_VOLATILE (fndecl)
1862 && TYPE_MODE (TREE_TYPE (exp)) != VOIDmode)
1865 if (TREE_THIS_VOLATILE (fndecl))
1868 if (TREE_NOTHROW (fndecl))
1873 /* If we don't have specific function to call, see if we have a
1874 constant or `noreturn' function from the type. */
1877 is_const = TREE_READONLY (TREE_TYPE (TREE_TYPE (p)));
1878 is_volatile = TREE_THIS_VOLATILE (TREE_TYPE (TREE_TYPE (p)));
1881 #ifdef REG_PARM_STACK_SPACE
1882 #ifdef MAYBE_REG_PARM_STACK_SPACE
1883 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1885 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1889 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1890 if (reg_parm_stack_space > 0 && PUSH_ARGS)
1891 must_preallocate = 1;
1894 /* Warn if this value is an aggregate type,
1895 regardless of which calling convention we are using for it. */
1896 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
1897 warning ("function call has aggregate value");
1899 /* Set up a place to return a structure. */
1901 /* Cater to broken compilers. */
1902 if (aggregate_value_p (exp))
1904 /* This call returns a big structure. */
1907 #ifdef PCC_STATIC_STRUCT_RETURN
1909 pcc_struct_value = 1;
1910 /* Easier than making that case work right. */
1913 /* In case this is a static function, note that it has been
1915 if (! TREE_ADDRESSABLE (fndecl))
1916 mark_addressable (fndecl);
1920 #else /* not PCC_STATIC_STRUCT_RETURN */
1922 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
1924 if (target && GET_CODE (target) == MEM)
1925 structure_value_addr = XEXP (target, 0);
1928 /* Assign a temporary to hold the value. */
1931 /* For variable-sized objects, we must be called with a target
1932 specified. If we were to allocate space on the stack here,
1933 we would have no way of knowing when to free it. */
1935 if (struct_value_size < 0)
1938 /* This DECL is just something to feed to mark_addressable;
1939 it doesn't get pushed. */
1940 d = build_decl (VAR_DECL, NULL_TREE, TREE_TYPE (exp));
1941 DECL_RTL (d) = assign_temp (TREE_TYPE (exp), 1, 0, 1);
1942 mark_addressable (d);
1943 mark_temp_addr_taken (DECL_RTL (d));
1944 structure_value_addr = XEXP (DECL_RTL (d), 0);
1949 #endif /* not PCC_STATIC_STRUCT_RETURN */
1952 /* If called function is inline, try to integrate it. */
1958 before_call = get_last_insn ();
1960 temp = expand_inline_function (fndecl, actparms, target,
1961 ignore, TREE_TYPE (exp),
1962 structure_value_addr);
1964 /* If inlining succeeded, return. */
1965 if (temp != (rtx) (HOST_WIDE_INT) -1)
1967 if (ACCUMULATE_OUTGOING_ARGS)
1969 /* If the outgoing argument list must be preserved, push
1970 the stack before executing the inlined function if it
1973 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1974 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1977 if (stack_arg_under_construction || i >= 0)
1980 = before_call ? NEXT_INSN (before_call) : get_insns ();
1981 rtx insn = NULL_RTX, seq;
1983 /* Look for a call in the inline function code.
1984 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1985 nonzero then there is a call and it is not necessary
1986 to scan the insns. */
1988 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1989 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1990 if (GET_CODE (insn) == CALL_INSN)
1995 /* Reserve enough stack space so that the largest
1996 argument list of any function call in the inline
1997 function does not overlap the argument list being
1998 evaluated. This is usually an overestimate because
1999 allocate_dynamic_stack_space reserves space for an
2000 outgoing argument list in addition to the requested
2001 space, but there is no way to ask for stack space such
2002 that an argument list of a certain length can be
2005 Add the stack space reserved for register arguments, if
2006 any, in the inline function. What is really needed is the
2007 largest value of reg_parm_stack_space in the inline
2008 function, but that is not available. Using the current
2009 value of reg_parm_stack_space is wrong, but gives
2010 correct results on all supported machines. */
2012 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
2013 + reg_parm_stack_space);
2016 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2017 allocate_dynamic_stack_space (GEN_INT (adjust),
2018 NULL_RTX, BITS_PER_UNIT);
2021 emit_insns_before (seq, first_insn);
2022 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
2027 /* If the result is equivalent to TARGET, return TARGET to simplify
2028 checks in store_expr. They can be equivalent but not equal in the
2029 case of a function that returns BLKmode. */
2030 if (temp != target && rtx_equal_p (temp, target))
2035 /* If inlining failed, mark FNDECL as needing to be compiled
2036 separately after all. If function was declared inline,
2038 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2039 && optimize > 0 && ! TREE_ADDRESSABLE (fndecl))
2041 warning_with_decl (fndecl, "inlining failed in call to `%s'");
2042 warning ("called from here");
2044 mark_addressable (fndecl);
2047 currently_expanding_call++;
2049 /* Tail calls can make things harder to debug, and we're traditionally
2050 pushed these optimizations into -O2. Don't try if we're already
2051 expanding a call, as that means we're an argument. Similarly, if
2052 there's pending loops or cleanups we know there's code to follow
2056 if (flag_optimize_sibling_calls
2057 && currently_expanding_call == 1
2058 && stmt_loop_nest_empty ()
2059 && ! any_pending_cleanups (1))
2061 tree new_actparms = NULL_TREE;
2063 /* Ok, we're going to give the tail call the old college try.
2064 This means we're going to evaluate the function arguments
2065 up to three times. There are two degrees of badness we can
2066 encounter, those that can be unsaved and those that can't.
2067 (See unsafe_for_reeval commentary for details.)
2069 Generate a new argument list. Pass safe arguments through
2070 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2071 For hard badness, evaluate them now and put their resulting
2072 rtx in a temporary VAR_DECL. */
2074 for (p = actparms; p; p = TREE_CHAIN (p))
2075 switch (unsafe_for_reeval (TREE_VALUE (p)))
2078 new_actparms = tree_cons (TREE_PURPOSE (p), TREE_VALUE (p),
2082 case 1: /* Mildly unsafe. */
2083 new_actparms = tree_cons (TREE_PURPOSE (p),
2084 unsave_expr (TREE_VALUE (p)),
2088 case 2: /* Wildly unsafe. */
2090 tree var = build_decl (VAR_DECL, NULL_TREE,
2091 TREE_TYPE (TREE_VALUE (p)));
2092 DECL_RTL (var) = expand_expr (TREE_VALUE (p), NULL_RTX,
2093 VOIDmode, EXPAND_NORMAL);
2094 new_actparms = tree_cons (TREE_PURPOSE (p), var, new_actparms);
2102 /* We built the new argument chain backwards. */
2103 actparms = nreverse (new_actparms);
2105 /* Expanding one of those dangerous arguments could have added
2106 cleanups, but otherwise give it a whirl. */
2107 try_tail_call = ! any_pending_cleanups (1);
2110 /* Generate a tail recursion sequence when calling ourselves. */
2113 && TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
2114 && TREE_OPERAND (TREE_OPERAND (exp, 0), 0) == current_function_decl)
2116 /* We want to emit any pending stack adjustments before the tail
2117 recursion "call". That way we know any adjustment after the tail
2118 recursion call can be ignored if we indeed use the tail recursion
2120 int save_pending_stack_adjust = pending_stack_adjust;
2122 /* Use a new sequence to hold any RTL we generate. We do not even
2123 know if we will use this RTL yet. The final decision can not be
2124 made until after RTL generation for the entire function is
2128 /* Emit the pending stack adjustments before we expand any arguments. */
2129 do_pending_stack_adjust ();
2131 if (optimize_tail_recursion (actparms, get_last_insn ()))
2132 tail_recursion_insns = get_insns ();
2135 /* Restore the original pending stack adjustment for the sibling and
2136 normal call cases below. */
2137 pending_stack_adjust = save_pending_stack_adjust;
2140 function_call_count++;
2142 if (fndecl && DECL_NAME (fndecl))
2143 name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
2145 #ifdef PREFERRED_STACK_BOUNDARY
2146 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2148 preferred_stack_boundary = STACK_BOUNDARY;
2151 /* Ensure current function's preferred stack boundary is at least
2152 what we need. We don't have to increase alignment for recursive
2154 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2155 && fndecl != current_function_decl)
2156 cfun->preferred_stack_boundary = preferred_stack_boundary;
2158 /* See if this is a call to a function that can return more than once
2159 or a call to longjmp or malloc. */
2160 special_function_p (fndecl, &returns_twice, &is_longjmp, &fork_or_exec,
2161 &is_malloc, &may_be_alloca);
2164 current_function_calls_alloca = 1;
2166 /* Operand 0 is a pointer-to-function; get the type of the function. */
2167 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
2168 if (! POINTER_TYPE_P (funtype))
2170 funtype = TREE_TYPE (funtype);
2172 /* We want to make two insn chains; one for a sibling call, the other
2173 for a normal call. We will select one of the two chains after
2174 initial RTL generation is complete. */
2175 for (pass = 0; pass < 2; pass++)
2177 int sibcall_failure = 0;
2178 /* We want to emit ay pending stack adjustments before the tail
2179 recursion "call". That way we know any adjustment after the tail
2180 recursion call can be ignored if we indeed use the tail recursion
2182 int save_pending_stack_adjust;
2184 rtx before_call, next_arg_reg;
2188 /* Various reasons we can not use a sibling call. */
2190 #ifdef HAVE_sibcall_epilogue
2191 || ! HAVE_sibcall_epilogue
2195 /* The structure value address is used and modified in the
2196 loop below. It does not seem worth the effort to save and
2197 restore it as a state variable since few optimizable
2198 sibling calls will return a structure. */
2199 || structure_value_addr != NULL_RTX
2200 /* If the register holding the address is a callee saved
2201 register, then we lose. We have no way to prevent that,
2202 so we only allow calls to named functions. */
2203 /* ??? This could be done by having the insn constraints
2204 use a register class that is all call-clobbered. Any
2205 reload insns generated to fix things up would appear
2206 before the sibcall_epilogue. */
2207 || fndecl == NULL_TREE
2208 || ! FUNCTION_OK_FOR_SIBCALL (fndecl))
2211 /* We know at this point that there are not currently any
2212 pending cleanups. If, however, in the process of evaluating
2213 the arguments we were to create some, we'll need to be
2214 able to get rid of them. */
2215 expand_start_target_temps ();
2217 /* State variables we need to save and restore between
2219 save_pending_stack_adjust = pending_stack_adjust;
2222 /* Other state variables that we must reinitialize each time
2223 through the loop (that are not initialized by the loop itself. */
2227 /* Start a new sequence for the normal call case.
2229 From this point on, if the sibling call fails, we want to set
2230 sibcall_failure instead of continuing the loop. */
2233 /* When calling a const function, we must pop the stack args right away,
2234 so that the pop is deleted or moved with the call. */
2238 /* Don't let pending stack adjusts add up to too much.
2239 Also, do all pending adjustments now if there is any chance
2240 this might be a call to alloca or if we are expanding a sibling
2242 if (pending_stack_adjust >= 32
2243 || (pending_stack_adjust > 0 && may_be_alloca)
2245 do_pending_stack_adjust ();
2247 if (profile_arc_flag && fork_or_exec)
2249 /* A fork duplicates the profile information, and an exec discards
2250 it. We can't rely on fork/exec to be paired. So write out the
2251 profile information we have gathered so far, and clear it. */
2252 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2253 is subject to race conditions, just as with multithreaded
2256 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__bb_fork_func"), 0,
2260 /* Push the temporary stack slot level so that we can free any
2261 temporaries we make. */
2264 /* Start updating where the next arg would go.
2266 On some machines (such as the PA) indirect calls have a different
2267 calling convention than normal calls. The last argument in
2268 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2270 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
2272 /* If struct_value_rtx is 0, it means pass the address
2273 as if it were an extra parameter. */
2274 if (structure_value_addr && struct_value_rtx == 0)
2276 /* If structure_value_addr is a REG other than
2277 virtual_outgoing_args_rtx, we can use always use it. If it
2278 is not a REG, we must always copy it into a register.
2279 If it is virtual_outgoing_args_rtx, we must copy it to another
2280 register in some cases. */
2281 rtx temp = (GET_CODE (structure_value_addr) != REG
2282 || (ACCUMULATE_OUTGOING_ARGS
2283 && stack_arg_under_construction
2284 && structure_value_addr == virtual_outgoing_args_rtx)
2285 ? copy_addr_to_reg (structure_value_addr)
2286 : structure_value_addr);
2289 = tree_cons (error_mark_node,
2290 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2293 structure_value_addr_parm = 1;
2296 /* Count the arguments and set NUM_ACTUALS. */
2297 for (p = actparms, i = 0; p; p = TREE_CHAIN (p)) i++;
2300 /* Compute number of named args.
2301 Normally, don't include the last named arg if anonymous args follow.
2302 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2303 (If no anonymous args follow, the result of list_length is actually
2304 one too large. This is harmless.)
2306 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2307 zero, this machine will be able to place unnamed args that were
2308 passed in registers into the stack. So treat all args as named.
2309 This allows the insns emitting for a specific argument list to be
2310 independent of the function declaration.
2312 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2313 reliable way to pass unnamed args in registers, so we must force
2314 them into memory. */
2316 if ((STRICT_ARGUMENT_NAMING
2317 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2318 && TYPE_ARG_TYPES (funtype) != 0)
2320 = (list_length (TYPE_ARG_TYPES (funtype))
2321 /* Don't include the last named arg. */
2322 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2323 /* Count the struct value address, if it is passed as a parm. */
2324 + structure_value_addr_parm);
2326 /* If we know nothing, treat all args as named. */
2327 n_named_args = num_actuals;
2329 /* Make a vector to hold all the information about each arg. */
2330 args = (struct arg_data *) alloca (num_actuals
2331 * sizeof (struct arg_data));
2332 bzero ((char *) args, num_actuals * sizeof (struct arg_data));
2334 /* Build up entries inthe ARGS array, compute the size of the arguments
2335 into ARGS_SIZE, etc. */
2336 initialize_argument_information (num_actuals, args, &args_size,
2337 n_named_args, actparms, fndecl,
2338 &args_so_far, reg_parm_stack_space,
2339 &old_stack_level, &old_pending_adj,
2340 &must_preallocate, &is_const,
2341 (pass == 0) ? ECF_SIBCALL : 0);
2343 #ifdef FINAL_REG_PARM_STACK_SPACE
2344 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2350 /* If this function requires a variable-sized argument list, don't
2351 try to make a cse'able block for this call. We may be able to
2352 do this eventually, but it is too complicated to keep track of
2353 what insns go in the cse'able block and which don't.
2355 Also do not make a sibling call. */
2358 must_preallocate = 1;
2359 sibcall_failure = 1;
2362 if (args_size.constant > current_function_args_size)
2364 /* If this function requires more stack slots than the current
2365 function, we cannot change it into a sibling call. */
2366 sibcall_failure = 1;
2369 /* Compute the actual size of the argument block required. The variable
2370 and constant sizes must be combined, the size may have to be rounded,
2371 and there may be a minimum required size. When generating a sibcall
2372 pattern, do not round up, since we'll be re-using whatever space our
2374 unadjusted_args_size
2375 = compute_argument_block_size (reg_parm_stack_space, &args_size,
2377 : preferred_stack_boundary));
2379 /* If the callee pops its own arguments, then it must pop exactly
2380 the same number of arguments as the current function. */
2381 if (RETURN_POPS_ARGS (fndecl, funtype, unadjusted_args_size)
2382 != RETURN_POPS_ARGS (current_function_decl,
2383 TREE_TYPE (current_function_decl),
2384 current_function_args_size))
2385 sibcall_failure = 1;
2387 /* Now make final decision about preallocating stack space. */
2388 must_preallocate = finalize_must_preallocate (must_preallocate,
2392 /* If the structure value address will reference the stack pointer, we
2393 must stabilize it. We don't need to do this if we know that we are
2394 not going to adjust the stack pointer in processing this call. */
2396 if (structure_value_addr
2397 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2398 || reg_mentioned_p (virtual_outgoing_args_rtx,
2399 structure_value_addr))
2401 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)
2403 structure_value_addr = copy_to_reg (structure_value_addr);
2405 /* Precompute any arguments as needed. */
2406 precompute_arguments (is_const, must_preallocate, num_actuals,
2409 /* Now we are about to start emitting insns that can be deleted
2410 if a libcall is deleted. */
2411 if (is_const || is_malloc)
2414 /* If we have no actual push instructions, or shouldn't use them,
2415 make space for all args right now. */
2417 if (args_size.var != 0)
2419 if (old_stack_level == 0)
2421 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2422 old_pending_adj = pending_stack_adjust;
2423 pending_stack_adjust = 0;
2424 /* stack_arg_under_construction says whether a stack arg is
2425 being constructed at the old stack level. Pushing the stack
2426 gets a clean outgoing argument block. */
2427 old_stack_arg_under_construction = stack_arg_under_construction;
2428 stack_arg_under_construction = 0;
2430 argblock = push_block (ARGS_SIZE_RTX (args_size), 0, 0);
2434 /* Note that we must go through the motions of allocating an argument
2435 block even if the size is zero because we may be storing args
2436 in the area reserved for register arguments, which may be part of
2439 int needed = args_size.constant;
2441 /* Store the maximum argument space used. It will be pushed by
2442 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2445 if (needed > current_function_outgoing_args_size)
2446 current_function_outgoing_args_size = needed;
2448 if (must_preallocate)
2450 if (ACCUMULATE_OUTGOING_ARGS)
2452 /* Since the stack pointer will never be pushed, it is possible
2453 for the evaluation of a parm to clobber something we have
2454 already written to the stack. Since most function calls on
2455 RISC machines do not use the stack, this is uncommon, but
2456 must work correctly.
2458 Therefore, we save any area of the stack that was already
2459 written and that we are using. Here we set up to do this by
2460 making a new stack usage map from the old one. The actual
2461 save will be done by store_one_arg.
2463 Another approach might be to try to reorder the argument
2464 evaluations to avoid this conflicting stack usage. */
2466 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2467 /* Since we will be writing into the entire argument area, the
2468 map must be allocated for its entire size, not just the part
2469 that is the responsibility of the caller. */
2470 needed += reg_parm_stack_space;
2473 #ifdef ARGS_GROW_DOWNWARD
2474 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2477 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2480 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
2482 if (initial_highest_arg_in_use)
2483 bcopy (initial_stack_usage_map, stack_usage_map,
2484 initial_highest_arg_in_use);
2486 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2487 bzero (&stack_usage_map[initial_highest_arg_in_use],
2488 (highest_outgoing_arg_in_use
2489 - initial_highest_arg_in_use));
2492 /* The address of the outgoing argument list must not be copied
2493 to a register here, because argblock would be left pointing
2494 to the wrong place after the call to
2495 allocate_dynamic_stack_space below. */
2497 argblock = virtual_outgoing_args_rtx;
2501 if (inhibit_defer_pop == 0)
2503 /* Try to reuse some or all of the pending_stack_adjust
2504 to get this space. Maybe we can avoid any pushing. */
2505 if (needed > pending_stack_adjust)
2507 needed -= pending_stack_adjust;
2508 pending_stack_adjust = 0;
2512 pending_stack_adjust -= needed;
2516 /* Special case this because overhead of `push_block' in this
2517 case is non-trivial. */
2519 argblock = virtual_outgoing_args_rtx;
2521 argblock = push_block (GEN_INT (needed), 0, 0);
2523 /* We only really need to call `copy_to_reg' in the case where
2524 push insns are going to be used to pass ARGBLOCK to a function
2525 call in ARGS. In that case, the stack pointer changes value
2526 from the allocation point to the call point, and hence
2527 the value of VIRTUAL_OUTGOING_ARGS_RTX changes as well.
2528 But might as well always do it. */
2529 argblock = copy_to_reg (argblock);
2534 /* The argument block when performing a sibling call is the
2535 incoming argument block. */
2538 rtx temp = plus_constant (arg_pointer_rtx,
2539 FIRST_PARM_OFFSET (current_function_decl));
2540 argblock = force_reg (Pmode, force_operand (temp, NULL_RTX));
2543 if (ACCUMULATE_OUTGOING_ARGS)
2545 /* The save/restore code in store_one_arg handles all cases except one:
2546 a constructor call (including a C function returning a BLKmode struct)
2547 to initialize an argument. */
2548 if (stack_arg_under_construction)
2550 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2551 rtx push_size = GEN_INT (reg_parm_stack_space + args_size.constant);
2553 rtx push_size = GEN_INT (args_size.constant);
2555 if (old_stack_level == 0)
2557 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2558 old_pending_adj = pending_stack_adjust;
2559 pending_stack_adjust = 0;
2560 /* stack_arg_under_construction says whether a stack arg is
2561 being constructed at the old stack level. Pushing the stack
2562 gets a clean outgoing argument block. */
2563 old_stack_arg_under_construction = stack_arg_under_construction;
2564 stack_arg_under_construction = 0;
2565 /* Make a new map for the new argument list. */
2566 stack_usage_map = (char *)alloca (highest_outgoing_arg_in_use);
2567 bzero (stack_usage_map, highest_outgoing_arg_in_use);
2568 highest_outgoing_arg_in_use = 0;
2570 allocate_dynamic_stack_space (push_size, NULL_RTX, BITS_PER_UNIT);
2572 /* If argument evaluation might modify the stack pointer, copy the
2573 address of the argument list to a register. */
2574 for (i = 0; i < num_actuals; i++)
2575 if (args[i].pass_on_stack)
2577 argblock = copy_addr_to_reg (argblock);
2582 compute_argument_addresses (args, argblock, num_actuals);
2584 #ifdef PREFERRED_STACK_BOUNDARY
2585 /* If we push args individually in reverse order, perform stack alignment
2586 before the first push (the last arg). */
2587 if (PUSH_ARGS_REVERSED && argblock == 0
2588 && args_size.constant != unadjusted_args_size)
2590 /* When the stack adjustment is pending, we get better code
2591 by combining the adjustments. */
2592 if (pending_stack_adjust && ! is_const
2593 && ! inhibit_defer_pop)
2595 args_size.constant = (unadjusted_args_size
2596 + ((pending_stack_adjust
2597 + args_size.constant
2599 - unadjusted_args_size)
2600 % (preferred_stack_boundary
2602 pending_stack_adjust -= (args_size.constant
2603 - unadjusted_args_size);
2604 do_pending_stack_adjust ();
2606 else if (argblock == 0)
2607 anti_adjust_stack (GEN_INT (args_size.constant
2608 - unadjusted_args_size));
2609 arg_space_so_far += args_size.constant - unadjusted_args_size;
2611 /* Now that the stack is properly aligned, pops can't safely
2612 be deferred during the evaluation of the arguments. */
2617 /* Don't try to defer pops if preallocating, not even from the first arg,
2618 since ARGBLOCK probably refers to the SP. */
2622 funexp = rtx_for_function_call (fndecl, exp);
2624 /* Figure out the register where the value, if any, will come back. */
2626 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2627 && ! structure_value_addr)
2629 if (pcc_struct_value)
2630 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2631 fndecl, (pass == 0));
2633 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2636 /* Precompute all register parameters. It isn't safe to compute anything
2637 once we have started filling any specific hard regs. */
2638 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2640 #ifdef REG_PARM_STACK_SPACE
2641 /* Save the fixed argument area if it's part of the caller's frame and
2642 is clobbered by argument setup for this call. */
2643 if (ACCUMULATE_OUTGOING_ARGS)
2644 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2645 &low_to_save, &high_to_save);
2648 /* Now store (and compute if necessary) all non-register parms.
2649 These come before register parms, since they can require block-moves,
2650 which could clobber the registers used for register parms.
2651 Parms which have partial registers are not stored here,
2652 but we do preallocate space here if they want that. */
2654 for (i = 0; i < num_actuals; i++)
2655 if (args[i].reg == 0 || args[i].pass_on_stack)
2656 store_one_arg (&args[i], argblock, may_be_alloca,
2657 args_size.var != 0, reg_parm_stack_space);
2659 /* If we have a parm that is passed in registers but not in memory
2660 and whose alignment does not permit a direct copy into registers,
2661 make a group of pseudos that correspond to each register that we
2663 if (STRICT_ALIGNMENT)
2664 store_unaligned_arguments_into_pseudos (args, num_actuals);
2666 /* Now store any partially-in-registers parm.
2667 This is the last place a block-move can happen. */
2669 for (i = 0; i < num_actuals; i++)
2670 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2671 store_one_arg (&args[i], argblock, may_be_alloca,
2672 args_size.var != 0, reg_parm_stack_space);
2674 #ifdef PREFERRED_STACK_BOUNDARY
2675 /* If we pushed args in forward order, perform stack alignment
2676 after pushing the last arg. */
2677 /* ??? Fix for arg_space_so_far. */
2678 if (!PUSH_ARGS_REVERSED && argblock == 0)
2679 anti_adjust_stack (GEN_INT (args_size.constant
2680 - unadjusted_args_size));
2683 /* If register arguments require space on the stack and stack space
2684 was not preallocated, allocate stack space here for arguments
2685 passed in registers. */
2686 #ifdef OUTGOING_REG_PARM_STACK_SPACE
2687 if (!ACCUMULATE_OUTGOING_ARGS
2688 && must_preallocate == 0 && reg_parm_stack_space > 0)
2689 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
2692 /* Pass the function the address in which to return a
2694 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
2696 emit_move_insn (struct_value_rtx,
2698 force_operand (structure_value_addr,
2701 /* Mark the memory for the aggregate as write-only. */
2702 if (current_function_check_memory_usage)
2703 emit_library_call (chkr_set_right_libfunc, 1,
2705 structure_value_addr, ptr_mode,
2706 GEN_INT (struct_value_size),
2707 TYPE_MODE (sizetype),
2708 GEN_INT (MEMORY_USE_WO),
2709 TYPE_MODE (integer_type_node));
2711 if (GET_CODE (struct_value_rtx) == REG)
2712 use_reg (&call_fusage, struct_value_rtx);
2715 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
2718 load_register_parameters (args, num_actuals, &call_fusage);
2720 /* Perform postincrements before actually calling the function. */
2723 /* Save a pointer to the last insn before the call, so that we can
2724 later safely search backwards to find the CALL_INSN. */
2725 before_call = get_last_insn ();
2727 /* Set up next argument register. For sibling calls on machines
2728 with register windows this should be the incoming register. */
2729 #ifdef FUNCTION_INCOMING_ARG
2731 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
2735 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
2738 /* All arguments and registers used for the call must be set up by
2741 /* Generate the actual call instruction. */
2742 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
2743 args_size.constant, struct_value_size,
2744 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
2745 ((is_const ? ECF_IS_CONST : 0)
2746 | (nothrow ? ECF_NOTHROW : 0)
2747 | (pass == 0 ? ECF_SIBCALL : 0)));
2749 /* If call is cse'able, make appropriate pair of reg-notes around it.
2750 Test valreg so we don't crash; may safely ignore `const'
2751 if return type is void. Disable for PARALLEL return values, because
2752 we have no way to move such values into a pseudo register. */
2753 if (is_const && valreg != 0 && GET_CODE (valreg) != PARALLEL)
2756 rtx temp = gen_reg_rtx (GET_MODE (valreg));
2759 /* Mark the return value as a pointer if needed. */
2760 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
2762 tree pointed_to = TREE_TYPE (TREE_TYPE (exp));
2763 mark_reg_pointer (temp, TYPE_ALIGN (pointed_to) / BITS_PER_UNIT);
2766 /* Construct an "equal form" for the value which mentions all the
2767 arguments in order as well as the function name. */
2768 if (PUSH_ARGS_REVERSED)
2769 for (i = 0; i < num_actuals; i++)
2770 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
2772 for (i = num_actuals - 1; i >= 0; i--)
2773 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
2774 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
2776 insns = get_insns ();
2779 emit_libcall_block (insns, temp, valreg, note);
2785 /* Otherwise, just write out the sequence without a note. */
2786 rtx insns = get_insns ();
2793 rtx temp = gen_reg_rtx (GET_MODE (valreg));
2796 /* The return value from a malloc-like function is a pointer. */
2797 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
2798 mark_reg_pointer (temp, BIGGEST_ALIGNMENT / BITS_PER_UNIT);
2800 emit_move_insn (temp, valreg);
2802 /* The return value from a malloc-like function can not alias
2804 last = get_last_insn ();
2806 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
2808 /* Write out the sequence. */
2809 insns = get_insns ();
2815 /* For calls to `setjmp', etc., inform flow.c it should complain
2816 if nonvolatile values are live. For functions that cannot return,
2817 inform flow that control does not fall through. */
2819 if (returns_twice || is_volatile || is_longjmp || pass == 0)
2821 /* The barrier or NOTE_INSN_SETJMP note must be emitted
2822 immediately after the CALL_INSN. Some ports emit more
2823 than just a CALL_INSN above, so we must search for it here. */
2825 rtx last = get_last_insn ();
2826 while (GET_CODE (last) != CALL_INSN)
2828 last = PREV_INSN (last);
2829 /* There was no CALL_INSN? */
2830 if (last == before_call)
2836 emit_note_after (NOTE_INSN_SETJMP, last);
2837 current_function_calls_setjmp = 1;
2838 sibcall_failure = 1;
2841 emit_barrier_after (last);
2845 current_function_calls_longjmp = 1, sibcall_failure = 1;
2847 /* If this function is returning into a memory location marked as
2848 readonly, it means it is initializing that location. But we normally
2849 treat functions as not clobbering such locations, so we need to
2850 specify that this one does. */
2851 if (target != 0 && GET_CODE (target) == MEM
2852 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
2853 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
2855 /* If value type not void, return an rtx for the value. */
2857 /* If there are cleanups to be called, don't use a hard reg as target.
2858 We need to double check this and see if it matters anymore. */
2859 if (any_pending_cleanups (1))
2861 if (target && REG_P (target)
2862 && REGNO (target) < FIRST_PSEUDO_REGISTER)
2864 sibcall_failure = 1;
2867 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
2870 target = const0_rtx;
2872 else if (structure_value_addr)
2874 if (target == 0 || GET_CODE (target) != MEM)
2876 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
2877 memory_address (TYPE_MODE (TREE_TYPE (exp)),
2878 structure_value_addr));
2879 MEM_SET_IN_STRUCT_P (target,
2880 AGGREGATE_TYPE_P (TREE_TYPE (exp)));
2883 else if (pcc_struct_value)
2885 /* This is the special C++ case where we need to
2886 know what the true target was. We take care to
2887 never use this value more than once in one expression. */
2888 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
2889 copy_to_reg (valreg));
2890 MEM_SET_IN_STRUCT_P (target, AGGREGATE_TYPE_P (TREE_TYPE (exp)));
2892 /* Handle calls that return values in multiple non-contiguous locations.
2893 The Irix 6 ABI has examples of this. */
2894 else if (GET_CODE (valreg) == PARALLEL)
2896 int bytes = int_size_in_bytes (TREE_TYPE (exp));
2900 target = assign_stack_temp (TYPE_MODE (TREE_TYPE (exp)),
2902 MEM_SET_IN_STRUCT_P (target, AGGREGATE_TYPE_P (TREE_TYPE (exp)));
2903 preserve_temp_slots (target);
2906 if (! rtx_equal_p (target, valreg))
2907 emit_group_store (target, valreg, bytes,
2908 TYPE_ALIGN (TREE_TYPE (exp)));
2910 /* We can not support sibling calls for this case. */
2911 sibcall_failure = 1;
2914 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
2915 && GET_MODE (target) == GET_MODE (valreg))
2917 /* TARGET and VALREG cannot be equal at this point because the
2918 latter would not have REG_FUNCTION_VALUE_P true, while the
2919 former would if it were referring to the same register.
2921 If they refer to the same register, this move will be a no-op,
2922 except when function inlining is being done. */
2923 emit_move_insn (target, valreg);
2925 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
2926 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
2928 target = copy_to_reg (valreg);
2930 #ifdef PROMOTE_FUNCTION_RETURN
2931 /* If we promoted this return value, make the proper SUBREG. TARGET
2932 might be const0_rtx here, so be careful. */
2933 if (GET_CODE (target) == REG
2934 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
2935 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
2937 tree type = TREE_TYPE (exp);
2938 int unsignedp = TREE_UNSIGNED (type);
2940 /* If we don't promote as expected, something is wrong. */
2941 if (GET_MODE (target)
2942 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
2945 target = gen_rtx_SUBREG (TYPE_MODE (type), target, 0);
2946 SUBREG_PROMOTED_VAR_P (target) = 1;
2947 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
2951 /* If size of args is variable or this was a constructor call for a stack
2952 argument, restore saved stack-pointer value. */
2954 if (old_stack_level)
2956 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
2957 pending_stack_adjust = old_pending_adj;
2958 stack_arg_under_construction = old_stack_arg_under_construction;
2959 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2960 stack_usage_map = initial_stack_usage_map;
2961 sibcall_failure = 1;
2963 else if (ACCUMULATE_OUTGOING_ARGS)
2965 #ifdef REG_PARM_STACK_SPACE
2968 restore_fixed_argument_area (save_area, argblock,
2969 high_to_save, low_to_save);
2970 sibcall_failure = 1;
2974 /* If we saved any argument areas, restore them. */
2975 for (i = 0; i < num_actuals; i++)
2976 if (args[i].save_area)
2978 enum machine_mode save_mode = GET_MODE (args[i].save_area);
2980 = gen_rtx_MEM (save_mode,
2981 memory_address (save_mode,
2982 XEXP (args[i].stack_slot, 0)));
2984 if (save_mode != BLKmode)
2985 emit_move_insn (stack_area, args[i].save_area);
2987 emit_block_move (stack_area,
2988 validize_mem (args[i].save_area),
2989 GEN_INT (args[i].size.constant),
2991 sibcall_failure = 1;
2994 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2995 stack_usage_map = initial_stack_usage_map;
2998 /* If this was alloca, record the new stack level for nonlocal gotos.
2999 Check for the handler slots since we might not have a save area
3000 for non-local gotos. */
3002 if (may_be_alloca && nonlocal_goto_handler_slots != 0)
3003 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3007 /* Free up storage we no longer need. */
3008 for (i = 0; i < num_actuals; ++i)
3009 if (args[i].aligned_regs)
3010 free (args[i].aligned_regs);
3014 /* Undo the fake expand_start_target_temps we did earlier. If
3015 there had been any cleanups created, we've already set
3017 expand_end_target_temps ();
3020 insns = get_insns ();
3025 tail_call_insns = insns;
3027 /* If something prevents making this a sibling call,
3028 zero out the sequence. */
3029 if (sibcall_failure)
3030 tail_call_insns = NULL_RTX;
3032 /* Restore the pending stack adjustment now that we have
3033 finished generating the sibling call sequence. */
3034 pending_stack_adjust = save_pending_stack_adjust;
3037 normal_call_insns = insns;
3040 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3041 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3042 can happen if the arguments to this function call an inline
3043 function who's expansion contains another CALL_PLACEHOLDER.
3045 If there are any C_Ps in any of these sequences, replace them
3046 with their normal call. */
3048 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3049 if (GET_CODE (insn) == CALL_INSN
3050 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3051 replace_call_placeholder (insn, sibcall_use_normal);
3053 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3054 if (GET_CODE (insn) == CALL_INSN
3055 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3056 replace_call_placeholder (insn, sibcall_use_normal);
3058 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3059 if (GET_CODE (insn) == CALL_INSN
3060 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3061 replace_call_placeholder (insn, sibcall_use_normal);
3063 /* If this was a potential tail recursion site, then emit a
3064 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3065 One of them will be selected later. */
3066 if (tail_recursion_insns || tail_call_insns)
3068 /* The tail recursion label must be kept around. We could expose
3069 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3070 and makes determining true tail recursion sites difficult.
3072 So we set LABEL_PRESERVE_P here, then clear it when we select
3073 one of the call sequences after rtl generation is complete. */
3074 if (tail_recursion_insns)
3075 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3076 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3078 tail_recursion_insns,
3079 tail_recursion_label));
3082 emit_insns (normal_call_insns);
3084 currently_expanding_call--;
3089 /* Returns nonzero if FUN is the symbol for a library function which can
3093 libfunc_nothrow (fun)
3096 if (fun == throw_libfunc
3097 || fun == rethrow_libfunc
3098 || fun == sjthrow_libfunc
3099 || fun == sjpopnthrow_libfunc)
3105 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3106 The RETVAL parameter specifies whether return value needs to be saved, other
3107 parameters are documented in the emit_library_call function bellow. */
3109 emit_library_call_value_1 (retval, orgfun, value, no_queue, outmode, nargs, p)
3114 enum machine_mode outmode;
3118 /* Total size in bytes of all the stack-parms scanned so far. */
3119 struct args_size args_size;
3120 /* Size of arguments before any adjustments (such as rounding). */
3121 struct args_size original_args_size;
3122 register int argnum;
3126 struct args_size alignment_pad;
3128 CUMULATIVE_ARGS args_so_far;
3129 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
3130 struct args_size offset; struct args_size size; rtx save_area; };
3132 int old_inhibit_defer_pop = inhibit_defer_pop;
3133 rtx call_fusage = 0;
3135 int pcc_struct_value = 0;
3136 int struct_value_size = 0;
3138 int reg_parm_stack_space = 0;
3142 #ifdef REG_PARM_STACK_SPACE
3143 /* Define the boundary of the register parm stack space that needs to be
3145 int low_to_save = -1, high_to_save = 0;
3146 rtx save_area = 0; /* Place that it is saved */
3149 /* Size of the stack reserved for parameter registers. */
3150 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3151 char *initial_stack_usage_map = stack_usage_map;
3153 #ifdef REG_PARM_STACK_SPACE
3154 #ifdef MAYBE_REG_PARM_STACK_SPACE
3155 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3157 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3161 is_const = no_queue;
3164 nothrow = libfunc_nothrow (fun);
3166 #ifdef PREFERRED_STACK_BOUNDARY
3167 /* Ensure current function's preferred stack boundary is at least
3169 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3170 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3173 /* If this kind of value comes back in memory,
3174 decide where in memory it should come back. */
3175 if (outmode != VOIDmode && aggregate_value_p (type_for_mode (outmode, 0)))
3177 #ifdef PCC_STATIC_STRUCT_RETURN
3179 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
3181 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3182 pcc_struct_value = 1;
3184 value = gen_reg_rtx (outmode);
3185 #else /* not PCC_STATIC_STRUCT_RETURN */
3186 struct_value_size = GET_MODE_SIZE (outmode);
3187 if (value != 0 && GET_CODE (value) == MEM)
3190 mem_value = assign_stack_temp (outmode, GET_MODE_SIZE (outmode), 0);
3193 /* This call returns a big structure. */
3197 /* ??? Unfinished: must pass the memory address as an argument. */
3199 /* Copy all the libcall-arguments out of the varargs data
3200 and into a vector ARGVEC.
3202 Compute how to pass each argument. We only support a very small subset
3203 of the full argument passing conventions to limit complexity here since
3204 library functions shouldn't have many args. */
3206 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3207 bzero ((char *) argvec, (nargs + 1) * sizeof (struct arg));
3209 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3211 args_size.constant = 0;
3218 /* If there's a structure value address to be passed,
3219 either pass it in the special place, or pass it as an extra argument. */
3220 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3222 rtx addr = XEXP (mem_value, 0);
3225 /* Make sure it is a reasonable operand for a move or push insn. */
3226 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3227 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3228 addr = force_operand (addr, NULL_RTX);
3230 argvec[count].value = addr;
3231 argvec[count].mode = Pmode;
3232 argvec[count].partial = 0;
3234 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3235 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3236 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3240 locate_and_pad_parm (Pmode, NULL_TREE,
3241 argvec[count].reg && argvec[count].partial == 0,
3242 NULL_TREE, &args_size, &argvec[count].offset,
3243 &argvec[count].size, &alignment_pad);
3246 if (argvec[count].reg == 0 || argvec[count].partial != 0
3247 || reg_parm_stack_space > 0)
3248 args_size.constant += argvec[count].size.constant;
3250 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3255 for (; count < nargs; count++)
3257 rtx val = va_arg (p, rtx);
3258 enum machine_mode mode = va_arg (p, enum machine_mode);
3260 /* We cannot convert the arg value to the mode the library wants here;
3261 must do it earlier where we know the signedness of the arg. */
3263 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3266 /* On some machines, there's no way to pass a float to a library fcn.
3267 Pass it as a double instead. */
3268 #ifdef LIBGCC_NEEDS_DOUBLE
3269 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3270 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3273 /* There's no need to call protect_from_queue, because
3274 either emit_move_insn or emit_push_insn will do that. */
3276 /* Make sure it is a reasonable operand for a move or push insn. */
3277 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3278 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3279 val = force_operand (val, NULL_RTX);
3281 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3282 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3284 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
3285 be viewed as just an efficiency improvement. */
3286 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
3287 emit_move_insn (slot, val);
3288 val = force_operand (XEXP (slot, 0), NULL_RTX);
3293 argvec[count].value = val;
3294 argvec[count].mode = mode;
3296 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3298 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3299 argvec[count].partial
3300 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3302 argvec[count].partial = 0;
3305 locate_and_pad_parm (mode, NULL_TREE,
3306 argvec[count].reg && argvec[count].partial == 0,
3307 NULL_TREE, &args_size, &argvec[count].offset,
3308 &argvec[count].size, &alignment_pad);
3310 if (argvec[count].size.var)
3313 if (reg_parm_stack_space == 0 && argvec[count].partial)
3314 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3316 if (argvec[count].reg == 0 || argvec[count].partial != 0
3317 || reg_parm_stack_space > 0)
3318 args_size.constant += argvec[count].size.constant;
3320 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3323 #ifdef FINAL_REG_PARM_STACK_SPACE
3324 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3327 /* If this machine requires an external definition for library
3328 functions, write one out. */
3329 assemble_external_libcall (fun);
3331 original_args_size = args_size;
3332 #ifdef PREFERRED_STACK_BOUNDARY
3333 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
3334 / STACK_BYTES) * STACK_BYTES);
3337 args_size.constant = MAX (args_size.constant,
3338 reg_parm_stack_space);
3340 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3341 args_size.constant -= reg_parm_stack_space;
3344 if (args_size.constant > current_function_outgoing_args_size)
3345 current_function_outgoing_args_size = args_size.constant;
3347 if (ACCUMULATE_OUTGOING_ARGS)
3349 /* Since the stack pointer will never be pushed, it is possible for
3350 the evaluation of a parm to clobber something we have already
3351 written to the stack. Since most function calls on RISC machines
3352 do not use the stack, this is uncommon, but must work correctly.
3354 Therefore, we save any area of the stack that was already written
3355 and that we are using. Here we set up to do this by making a new
3356 stack usage map from the old one.
3358 Another approach might be to try to reorder the argument
3359 evaluations to avoid this conflicting stack usage. */
3361 needed = args_size.constant;
3363 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3364 /* Since we will be writing into the entire argument area, the
3365 map must be allocated for its entire size, not just the part that
3366 is the responsibility of the caller. */
3367 needed += reg_parm_stack_space;
3370 #ifdef ARGS_GROW_DOWNWARD
3371 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3374 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3377 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3379 if (initial_highest_arg_in_use)
3380 bcopy (initial_stack_usage_map, stack_usage_map,
3381 initial_highest_arg_in_use);
3383 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3384 bzero (&stack_usage_map[initial_highest_arg_in_use],
3385 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3388 /* The address of the outgoing argument list must not be copied to a
3389 register here, because argblock would be left pointing to the
3390 wrong place after the call to allocate_dynamic_stack_space below.
3393 argblock = virtual_outgoing_args_rtx;
3398 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3401 #ifdef PREFERRED_STACK_BOUNDARY
3402 /* If we push args individually in reverse order, perform stack alignment
3403 before the first push (the last arg). */
3404 if (argblock == 0 && PUSH_ARGS_REVERSED)
3405 anti_adjust_stack (GEN_INT (args_size.constant
3406 - original_args_size.constant));
3409 if (PUSH_ARGS_REVERSED)
3420 #ifdef REG_PARM_STACK_SPACE
3421 if (ACCUMULATE_OUTGOING_ARGS)
3423 /* The argument list is the property of the called routine and it
3424 may clobber it. If the fixed area has been used for previous
3425 parameters, we must save and restore it.
3427 Here we compute the boundary of the that needs to be saved, if any. */
3429 #ifdef ARGS_GROW_DOWNWARD
3430 for (count = 0; count < reg_parm_stack_space + 1; count++)
3432 for (count = 0; count < reg_parm_stack_space; count++)
3435 if (count >= highest_outgoing_arg_in_use
3436 || stack_usage_map[count] == 0)
3439 if (low_to_save == -1)
3440 low_to_save = count;
3442 high_to_save = count;
3445 if (low_to_save >= 0)
3447 int num_to_save = high_to_save - low_to_save + 1;
3448 enum machine_mode save_mode
3449 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3452 /* If we don't have the required alignment, must do this in BLKmode. */
3453 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3454 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3455 save_mode = BLKmode;
3457 #ifdef ARGS_GROW_DOWNWARD
3458 stack_area = gen_rtx_MEM (save_mode,
3459 memory_address (save_mode,
3460 plus_constant (argblock,
3463 stack_area = gen_rtx_MEM (save_mode,
3464 memory_address (save_mode,
3465 plus_constant (argblock,
3468 if (save_mode == BLKmode)
3470 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3471 emit_block_move (validize_mem (save_area), stack_area,
3472 GEN_INT (num_to_save), PARM_BOUNDARY);
3476 save_area = gen_reg_rtx (save_mode);
3477 emit_move_insn (save_area, stack_area);
3483 /* Push the args that need to be pushed. */
3485 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3486 are to be pushed. */
3487 for (count = 0; count < nargs; count++, argnum += inc)
3489 register enum machine_mode mode = argvec[argnum].mode;
3490 register rtx val = argvec[argnum].value;
3491 rtx reg = argvec[argnum].reg;
3492 int partial = argvec[argnum].partial;
3493 int lower_bound = 0, upper_bound = 0, i;
3495 if (! (reg != 0 && partial == 0))
3497 if (ACCUMULATE_OUTGOING_ARGS)
3499 /* If this is being stored into a pre-allocated, fixed-size, stack
3500 area, save any previous data at that location. */
3502 #ifdef ARGS_GROW_DOWNWARD
3503 /* stack_slot is negative, but we want to index stack_usage_map
3504 with positive values. */
3505 upper_bound = -argvec[argnum].offset.constant + 1;
3506 lower_bound = upper_bound - argvec[argnum].size.constant;
3508 lower_bound = argvec[argnum].offset.constant;
3509 upper_bound = lower_bound + argvec[argnum].size.constant;
3512 for (i = lower_bound; i < upper_bound; i++)
3513 if (stack_usage_map[i]
3514 /* Don't store things in the fixed argument area at this point;
3515 it has already been saved. */
3516 && i > reg_parm_stack_space)
3519 if (i != upper_bound)
3521 /* We need to make a save area. See what mode we can make it. */
3522 enum machine_mode save_mode
3523 = mode_for_size (argvec[argnum].size.constant * BITS_PER_UNIT,
3530 plus_constant (argblock,
3531 argvec[argnum].offset.constant)));
3532 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3534 emit_move_insn (argvec[argnum].save_area, stack_area);
3538 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
3539 argblock, GEN_INT (argvec[argnum].offset.constant),
3540 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3542 /* Now mark the segment we just used. */
3543 if (ACCUMULATE_OUTGOING_ARGS)
3544 for (i = lower_bound; i < upper_bound; i++)
3545 stack_usage_map[i] = 1;
3551 #ifdef PREFERRED_STACK_BOUNDARY
3552 /* If we pushed args in forward order, perform stack alignment
3553 after pushing the last arg. */
3554 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3555 anti_adjust_stack (GEN_INT (args_size.constant
3556 - original_args_size.constant));
3559 if (PUSH_ARGS_REVERSED)
3564 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
3566 /* Now load any reg parms into their regs. */
3568 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3569 are to be pushed. */
3570 for (count = 0; count < nargs; count++, argnum += inc)
3572 register rtx val = argvec[argnum].value;
3573 rtx reg = argvec[argnum].reg;
3574 int partial = argvec[argnum].partial;
3576 /* Handle calls that pass values in multiple non-contiguous
3577 locations. The PA64 has examples of this for library calls. */
3578 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3579 emit_group_load (reg, val,
3580 GET_MODE_SIZE (GET_MODE (val)),
3581 GET_MODE_ALIGNMENT (GET_MODE (val)));
3582 else if (reg != 0 && partial == 0)
3583 emit_move_insn (reg, val);
3589 /* For version 1.37, try deleting this entirely. */
3594 /* Any regs containing parms remain in use through the call. */
3595 for (count = 0; count < nargs; count++)
3597 rtx reg = argvec[count].reg;
3598 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3599 use_group_regs (&call_fusage, reg);
3601 use_reg (&call_fusage, reg);
3604 /* Pass the function the address in which to return a structure value. */
3605 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
3607 emit_move_insn (struct_value_rtx,
3609 force_operand (XEXP (mem_value, 0),
3611 if (GET_CODE (struct_value_rtx) == REG)
3612 use_reg (&call_fusage, struct_value_rtx);
3615 /* Don't allow popping to be deferred, since then
3616 cse'ing of library calls could delete a call and leave the pop. */
3619 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3620 will set inhibit_defer_pop to that value. */
3621 /* The return type is needed to decide how many bytes the function pops.
3622 Signedness plays no role in that, so for simplicity, we pretend it's
3623 always signed. We also assume that the list of arguments passed has
3624 no impact, so we pretend it is unknown. */
3627 get_identifier (XSTR (orgfun, 0)),
3628 build_function_type (outmode == VOIDmode ? void_type_node
3629 : type_for_mode (outmode, 0), NULL_TREE),
3630 original_args_size.constant, args_size.constant,
3632 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
3633 mem_value == 0 && outmode != VOIDmode ? hard_libcall_value (outmode) : NULL_RTX,
3634 old_inhibit_defer_pop + 1, call_fusage,
3635 ((is_const ? ECF_IS_CONST : 0)
3636 | (nothrow ? ECF_NOTHROW : 0)));
3638 /* Now restore inhibit_defer_pop to its actual original value. */
3643 /* Copy the value to the right place. */
3644 if (outmode != VOIDmode && retval)
3650 if (value != mem_value)
3651 emit_move_insn (value, mem_value);
3653 else if (value != 0)
3654 emit_move_insn (value, hard_libcall_value (outmode));
3656 value = hard_libcall_value (outmode);
3659 if (ACCUMULATE_OUTGOING_ARGS)
3661 #ifdef REG_PARM_STACK_SPACE
3664 enum machine_mode save_mode = GET_MODE (save_area);
3665 #ifdef ARGS_GROW_DOWNWARD
3667 = gen_rtx_MEM (save_mode,
3668 memory_address (save_mode,
3669 plus_constant (argblock,
3673 = gen_rtx_MEM (save_mode,
3674 memory_address (save_mode,
3675 plus_constant (argblock, low_to_save)));
3677 if (save_mode != BLKmode)
3678 emit_move_insn (stack_area, save_area);
3680 emit_block_move (stack_area, validize_mem (save_area),
3681 GEN_INT (high_to_save - low_to_save + 1),
3686 /* If we saved any argument areas, restore them. */
3687 for (count = 0; count < nargs; count++)
3688 if (argvec[count].save_area)
3690 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
3692 = gen_rtx_MEM (save_mode,
3695 plus_constant (argblock,
3696 argvec[count].offset.constant)));
3698 emit_move_insn (stack_area, argvec[count].save_area);
3701 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3702 stack_usage_map = initial_stack_usage_map;
3709 /* Output a library call to function FUN (a SYMBOL_REF rtx)
3710 (emitting the queue unless NO_QUEUE is nonzero),
3711 for a value of mode OUTMODE,
3712 with NARGS different arguments, passed as alternating rtx values
3713 and machine_modes to convert them to.
3714 The rtx values should have been passed through protect_from_queue already.
3716 NO_QUEUE will be true if and only if the library call is a `const' call
3717 which will be enclosed in REG_LIBCALL/REG_RETVAL notes; it is equivalent
3718 to the variable is_const in expand_call.
3720 NO_QUEUE must be true for const calls, because if it isn't, then
3721 any pending increment will be emitted between REG_LIBCALL/REG_RETVAL notes,
3722 and will be lost if the libcall sequence is optimized away.
3724 NO_QUEUE must be false for non-const calls, because if it isn't, the
3725 call insn will have its CONST_CALL_P bit set, and it will be incorrectly
3726 optimized. For instance, the instruction scheduler may incorrectly
3727 move memory references across the non-const call. */
3730 emit_library_call VPARAMS((rtx orgfun, int no_queue, enum machine_mode outmode,
3733 #ifndef ANSI_PROTOTYPES
3736 enum machine_mode outmode;
3741 VA_START (p, nargs);
3743 #ifndef ANSI_PROTOTYPES
3744 orgfun = va_arg (p, rtx);
3745 no_queue = va_arg (p, int);
3746 outmode = va_arg (p, enum machine_mode);
3747 nargs = va_arg (p, int);
3750 emit_library_call_value_1 (0, orgfun, NULL_RTX, no_queue, outmode, nargs, p);
3755 /* Like emit_library_call except that an extra argument, VALUE,
3756 comes second and says where to store the result.
3757 (If VALUE is zero, this function chooses a convenient way
3758 to return the value.
3760 This function returns an rtx for where the value is to be found.
3761 If VALUE is nonzero, VALUE is returned. */
3764 emit_library_call_value VPARAMS((rtx orgfun, rtx value, int no_queue,
3765 enum machine_mode outmode, int nargs, ...))
3767 #ifndef ANSI_PROTOTYPES
3771 enum machine_mode outmode;
3776 VA_START (p, nargs);
3778 #ifndef ANSI_PROTOTYPES
3779 orgfun = va_arg (p, rtx);
3780 value = va_arg (p, rtx);
3781 no_queue = va_arg (p, int);
3782 outmode = va_arg (p, enum machine_mode);
3783 nargs = va_arg (p, int);
3786 value = emit_library_call_value_1 (1, orgfun, value, no_queue, outmode, nargs, p);
3794 /* Return an rtx which represents a suitable home on the stack
3795 given TYPE, the type of the argument looking for a home.
3796 This is called only for BLKmode arguments.
3798 SIZE is the size needed for this target.
3799 ARGS_ADDR is the address of the bottom of the argument block for this call.
3800 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
3801 if this machine uses push insns. */
3804 target_for_arg (type, size, args_addr, offset)
3808 struct args_size offset;
3811 rtx offset_rtx = ARGS_SIZE_RTX (offset);
3813 /* We do not call memory_address if possible,
3814 because we want to address as close to the stack
3815 as possible. For non-variable sized arguments,
3816 this will be stack-pointer relative addressing. */
3817 if (GET_CODE (offset_rtx) == CONST_INT)
3818 target = plus_constant (args_addr, INTVAL (offset_rtx));
3821 /* I have no idea how to guarantee that this
3822 will work in the presence of register parameters. */
3823 target = gen_rtx_PLUS (Pmode, args_addr, offset_rtx);
3824 target = memory_address (QImode, target);
3827 return gen_rtx_MEM (BLKmode, target);
3831 /* Store a single argument for a function call
3832 into the register or memory area where it must be passed.
3833 *ARG describes the argument value and where to pass it.
3835 ARGBLOCK is the address of the stack-block for all the arguments,
3836 or 0 on a machine where arguments are pushed individually.
3838 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
3839 so must be careful about how the stack is used.
3841 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
3842 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
3843 that we need not worry about saving and restoring the stack.
3845 FNDECL is the declaration of the function we are calling. */
3848 store_one_arg (arg, argblock, may_be_alloca, variable_size,
3849 reg_parm_stack_space)
3850 struct arg_data *arg;
3853 int variable_size ATTRIBUTE_UNUSED;
3854 int reg_parm_stack_space;
3856 register tree pval = arg->tree_value;
3860 int i, lower_bound = 0, upper_bound = 0;
3862 if (TREE_CODE (pval) == ERROR_MARK)
3865 /* Push a new temporary level for any temporaries we make for
3869 if (ACCUMULATE_OUTGOING_ARGS)
3871 /* If this is being stored into a pre-allocated, fixed-size, stack area,
3872 save any previous data at that location. */
3873 if (argblock && ! variable_size && arg->stack)
3875 #ifdef ARGS_GROW_DOWNWARD
3876 /* stack_slot is negative, but we want to index stack_usage_map
3877 with positive values. */
3878 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
3879 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
3883 lower_bound = upper_bound - arg->size.constant;
3885 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
3886 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
3890 upper_bound = lower_bound + arg->size.constant;
3893 for (i = lower_bound; i < upper_bound; i++)
3894 if (stack_usage_map[i]
3895 /* Don't store things in the fixed argument area at this point;
3896 it has already been saved. */
3897 && i > reg_parm_stack_space)
3900 if (i != upper_bound)
3902 /* We need to make a save area. See what mode we can make it. */
3903 enum machine_mode save_mode
3904 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
3906 = gen_rtx_MEM (save_mode,
3907 memory_address (save_mode,
3908 XEXP (arg->stack_slot, 0)));
3910 if (save_mode == BLKmode)
3912 arg->save_area = assign_stack_temp (BLKmode,
3913 arg->size.constant, 0);
3914 MEM_SET_IN_STRUCT_P (arg->save_area,
3915 AGGREGATE_TYPE_P (TREE_TYPE
3916 (arg->tree_value)));
3917 preserve_temp_slots (arg->save_area);
3918 emit_block_move (validize_mem (arg->save_area), stack_area,
3919 GEN_INT (arg->size.constant),
3924 arg->save_area = gen_reg_rtx (save_mode);
3925 emit_move_insn (arg->save_area, stack_area);
3929 /* Now that we have saved any slots that will be overwritten by this
3930 store, mark all slots this store will use. We must do this before
3931 we actually expand the argument since the expansion itself may
3932 trigger library calls which might need to use the same stack slot. */
3933 if (argblock && ! variable_size && arg->stack)
3934 for (i = lower_bound; i < upper_bound; i++)
3935 stack_usage_map[i] = 1;
3938 /* If this isn't going to be placed on both the stack and in registers,
3939 set up the register and number of words. */
3940 if (! arg->pass_on_stack)
3941 reg = arg->reg, partial = arg->partial;
3943 if (reg != 0 && partial == 0)
3944 /* Being passed entirely in a register. We shouldn't be called in
3948 /* If this arg needs special alignment, don't load the registers
3950 if (arg->n_aligned_regs != 0)
3953 /* If this is being passed partially in a register, we can't evaluate
3954 it directly into its stack slot. Otherwise, we can. */
3955 if (arg->value == 0)
3957 /* stack_arg_under_construction is nonzero if a function argument is
3958 being evaluated directly into the outgoing argument list and
3959 expand_call must take special action to preserve the argument list
3960 if it is called recursively.
3962 For scalar function arguments stack_usage_map is sufficient to
3963 determine which stack slots must be saved and restored. Scalar
3964 arguments in general have pass_on_stack == 0.
3966 If this argument is initialized by a function which takes the
3967 address of the argument (a C++ constructor or a C function
3968 returning a BLKmode structure), then stack_usage_map is
3969 insufficient and expand_call must push the stack around the
3970 function call. Such arguments have pass_on_stack == 1.
3972 Note that it is always safe to set stack_arg_under_construction,
3973 but this generates suboptimal code if set when not needed. */
3975 if (arg->pass_on_stack)
3976 stack_arg_under_construction++;
3978 arg->value = expand_expr (pval,
3980 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
3981 ? NULL_RTX : arg->stack,
3984 /* If we are promoting object (or for any other reason) the mode
3985 doesn't agree, convert the mode. */
3987 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
3988 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
3989 arg->value, arg->unsignedp);
3991 if (arg->pass_on_stack)
3992 stack_arg_under_construction--;
3995 /* Don't allow anything left on stack from computation
3996 of argument to alloca. */
3998 do_pending_stack_adjust ();
4000 if (arg->value == arg->stack)
4002 /* If the value is already in the stack slot, we are done. */
4003 if (current_function_check_memory_usage && GET_CODE (arg->stack) == MEM)
4005 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4006 XEXP (arg->stack, 0), Pmode,
4007 ARGS_SIZE_RTX (arg->size),
4008 TYPE_MODE (sizetype),
4009 GEN_INT (MEMORY_USE_RW),
4010 TYPE_MODE (integer_type_node));
4013 else if (arg->mode != BLKmode)
4017 /* Argument is a scalar, not entirely passed in registers.
4018 (If part is passed in registers, arg->partial says how much
4019 and emit_push_insn will take care of putting it there.)
4021 Push it, and if its size is less than the
4022 amount of space allocated to it,
4023 also bump stack pointer by the additional space.
4024 Note that in C the default argument promotions
4025 will prevent such mismatches. */
4027 size = GET_MODE_SIZE (arg->mode);
4028 /* Compute how much space the push instruction will push.
4029 On many machines, pushing a byte will advance the stack
4030 pointer by a halfword. */
4031 #ifdef PUSH_ROUNDING
4032 size = PUSH_ROUNDING (size);
4036 /* Compute how much space the argument should get:
4037 round up to a multiple of the alignment for arguments. */
4038 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4039 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4040 / (PARM_BOUNDARY / BITS_PER_UNIT))
4041 * (PARM_BOUNDARY / BITS_PER_UNIT));
4043 /* This isn't already where we want it on the stack, so put it there.
4044 This can either be done with push or copy insns. */
4045 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX, 0,
4046 partial, reg, used - size, argblock,
4047 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4048 ARGS_SIZE_RTX (arg->alignment_pad));
4050 arg_space_so_far += used;
4054 /* BLKmode, at least partly to be pushed. */
4056 register int excess;
4059 /* Pushing a nonscalar.
4060 If part is passed in registers, PARTIAL says how much
4061 and emit_push_insn will take care of putting it there. */
4063 /* Round its size up to a multiple
4064 of the allocation unit for arguments. */
4066 if (arg->size.var != 0)
4069 size_rtx = ARGS_SIZE_RTX (arg->size);
4073 /* PUSH_ROUNDING has no effect on us, because
4074 emit_push_insn for BLKmode is careful to avoid it. */
4075 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4076 + partial * UNITS_PER_WORD);
4077 size_rtx = expr_size (pval);
4078 arg_space_so_far += excess + INTVAL (size_rtx);
4081 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4082 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg, excess,
4083 argblock, ARGS_SIZE_RTX (arg->offset),
4084 reg_parm_stack_space,
4085 ARGS_SIZE_RTX (arg->alignment_pad));
4089 /* Unless this is a partially-in-register argument, the argument is now
4092 ??? Note that this can change arg->value from arg->stack to
4093 arg->stack_slot and it matters when they are not the same.
4094 It isn't totally clear that this is correct in all cases. */
4096 arg->value = arg->stack_slot;
4098 /* Once we have pushed something, pops can't safely
4099 be deferred during the rest of the arguments. */
4102 /* ANSI doesn't require a sequence point here,
4103 but PCC has one, so this will avoid some problems. */
4106 /* Free any temporary slots made in processing this argument. Show
4107 that we might have taken the address of something and pushed that
4109 preserve_temp_slots (NULL_RTX);