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 #if !defined FUNCTION_OK_FOR_SIBCALL
36 #define FUNCTION_OK_FOR_SIBCALL(DECL) 1
39 #if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY
40 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
43 /* Decide whether a function's arguments should be processed
44 from first to last or from last to first.
46 They should if the stack and args grow in opposite directions, but
47 only if we have push insns. */
51 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
52 #define PUSH_ARGS_REVERSED /* If it's last to first */
57 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
58 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
60 /* Data structure and subroutines used within expand_call. */
64 /* Tree node for this argument. */
66 /* Mode for value; TYPE_MODE unless promoted. */
67 enum machine_mode mode;
68 /* Current RTL value for argument, or 0 if it isn't precomputed. */
70 /* Initially-compute RTL value for argument; only for const functions. */
72 /* Register to pass this argument in, 0 if passed on stack, or an
73 PARALLEL if the arg is to be copied into multiple non-contiguous
76 /* If REG was promoted from the actual mode of the argument expression,
77 indicates whether the promotion is sign- or zero-extended. */
79 /* Number of registers to use. 0 means put the whole arg in registers.
80 Also 0 if not passed in registers. */
82 /* Non-zero if argument must be passed on stack.
83 Note that some arguments may be passed on the stack
84 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
85 pass_on_stack identifies arguments that *cannot* go in registers. */
87 /* Offset of this argument from beginning of stack-args. */
88 struct args_size offset;
89 /* Similar, but offset to the start of the stack slot. Different from
90 OFFSET if this arg pads downward. */
91 struct args_size slot_offset;
92 /* Size of this argument on the stack, rounded up for any padding it gets,
93 parts of the argument passed in registers do not count.
94 If REG_PARM_STACK_SPACE is defined, then register parms
95 are counted here as well. */
96 struct args_size size;
97 /* Location on the stack at which parameter should be stored. The store
98 has already been done if STACK == VALUE. */
100 /* Location on the stack of the start of this argument slot. This can
101 differ from STACK if this arg pads downward. This location is known
102 to be aligned to FUNCTION_ARG_BOUNDARY. */
104 #ifdef ACCUMULATE_OUTGOING_ARGS
105 /* Place that this stack area has been saved, if needed. */
108 /* If an argument's alignment does not permit direct copying into registers,
109 copy in smaller-sized pieces into pseudos. These are stored in a
110 block pointed to by this field. The next field says how many
111 word-sized pseudos we made. */
114 /* The amount that the stack pointer needs to be adjusted to
115 force alignment for the next argument. */
116 struct args_size alignment_pad;
119 #ifdef ACCUMULATE_OUTGOING_ARGS
120 /* A vector of one char per byte of stack space. A byte if non-zero if
121 the corresponding stack location has been used.
122 This vector is used to prevent a function call within an argument from
123 clobbering any stack already set up. */
124 static char *stack_usage_map;
126 /* Size of STACK_USAGE_MAP. */
127 static int highest_outgoing_arg_in_use;
129 /* stack_arg_under_construction is nonzero when an argument may be
130 initialized with a constructor call (including a C function that
131 returns a BLKmode struct) and expand_call must take special action
132 to make sure the object being constructed does not overlap the
133 argument list for the constructor call. */
134 int stack_arg_under_construction;
137 static int calls_function PARAMS ((tree, int));
138 static int calls_function_1 PARAMS ((tree, int));
140 #define ECF_IS_CONST 1
141 #define ECF_NOTHROW 2
142 #define ECF_SIBCALL 4
143 static void emit_call_1 PARAMS ((rtx, tree, tree, HOST_WIDE_INT,
144 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
145 rtx, int, rtx, int));
146 static void precompute_register_parameters PARAMS ((int,
149 static void store_one_arg PARAMS ((struct arg_data *, rtx, int, int,
151 static void store_unaligned_arguments_into_pseudos PARAMS ((struct arg_data *,
153 static int finalize_must_preallocate PARAMS ((int, int,
155 struct args_size *));
156 static void precompute_arguments PARAMS ((int, int, int,
158 struct args_size *));
159 static int compute_argument_block_size PARAMS ((int,
162 static void initialize_argument_information PARAMS ((int,
169 static void compute_argument_addresses PARAMS ((struct arg_data *,
171 static rtx rtx_for_function_call PARAMS ((tree, tree));
172 static void load_register_parameters PARAMS ((struct arg_data *,
174 static int libfunc_nothrow PARAMS ((rtx));
175 static rtx emit_library_call_value_1 PARAMS ((int, rtx, rtx, int,
179 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
180 static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
181 static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
184 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
187 If WHICH is 0, return 1 if EXP contains a call to any function.
188 Actually, we only need return 1 if evaluating EXP would require pushing
189 arguments on the stack, but that is too difficult to compute, so we just
190 assume any function call might require the stack. */
192 static tree calls_function_save_exprs;
195 calls_function (exp, which)
200 calls_function_save_exprs = 0;
201 val = calls_function_1 (exp, which);
202 calls_function_save_exprs = 0;
207 calls_function_1 (exp, which)
212 enum tree_code code = TREE_CODE (exp);
213 int type = TREE_CODE_CLASS (code);
214 int length = tree_code_length[(int) code];
216 /* If this code is language-specific, we don't know what it will do. */
217 if ((int) code >= NUM_TREE_CODES)
220 /* Only expressions and references can contain calls. */
221 if (type != 'e' && type != '<' && type != '1' && type != '2' && type != 'r'
230 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
231 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
234 tree fndecl = TREE_OPERAND (TREE_OPERAND (exp, 0), 0);
236 if ((DECL_BUILT_IN (fndecl)
237 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
238 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_ALLOCA)
239 || (DECL_SAVED_INSNS (fndecl)
240 && DECL_SAVED_INSNS (fndecl)->calls_alloca))
244 /* Third operand is RTL. */
249 if (SAVE_EXPR_RTL (exp) != 0)
251 if (value_member (exp, calls_function_save_exprs))
253 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
254 calls_function_save_exprs);
255 return (TREE_OPERAND (exp, 0) != 0
256 && calls_function_1 (TREE_OPERAND (exp, 0), which));
262 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
263 if (DECL_INITIAL (local) != 0
264 && calls_function_1 (DECL_INITIAL (local), which))
268 register tree subblock;
270 for (subblock = BLOCK_SUBBLOCKS (exp);
272 subblock = TREE_CHAIN (subblock))
273 if (calls_function_1 (subblock, which))
278 case METHOD_CALL_EXPR:
282 case WITH_CLEANUP_EXPR:
293 for (i = 0; i < length; i++)
294 if (TREE_OPERAND (exp, i) != 0
295 && calls_function_1 (TREE_OPERAND (exp, i), which))
301 /* Force FUNEXP into a form suitable for the address of a CALL,
302 and return that as an rtx. Also load the static chain register
303 if FNDECL is a nested function.
305 CALL_FUSAGE points to a variable holding the prospective
306 CALL_INSN_FUNCTION_USAGE information. */
309 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen)
315 rtx static_chain_value = 0;
317 funexp = protect_from_queue (funexp, 0);
320 /* Get possible static chain value for nested function in C. */
321 static_chain_value = lookup_static_chain (fndecl);
323 /* Make a valid memory address and copy constants thru pseudo-regs,
324 but not for a constant address if -fno-function-cse. */
325 if (GET_CODE (funexp) != SYMBOL_REF)
326 /* If we are using registers for parameters, force the
327 function address into a register now. */
328 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
329 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
330 : memory_address (FUNCTION_MODE, funexp));
333 #ifndef NO_FUNCTION_CSE
334 if (optimize && ! flag_no_function_cse)
335 #ifdef NO_RECURSIVE_FUNCTION_CSE
336 if (fndecl != current_function_decl)
338 funexp = force_reg (Pmode, funexp);
342 if (static_chain_value != 0)
344 emit_move_insn (static_chain_rtx, static_chain_value);
346 if (GET_CODE (static_chain_rtx) == REG)
347 use_reg (call_fusage, static_chain_rtx);
353 /* Generate instructions to call function FUNEXP,
354 and optionally pop the results.
355 The CALL_INSN is the first insn generated.
357 FNDECL is the declaration node of the function. This is given to the
358 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
360 FUNTYPE is the data type of the function. This is given to the macro
361 RETURN_POPS_ARGS to determine whether this function pops its own args.
362 We used to allow an identifier for library functions, but that doesn't
363 work when the return type is an aggregate type and the calling convention
364 says that the pointer to this aggregate is to be popped by the callee.
366 STACK_SIZE is the number of bytes of arguments on the stack,
367 ROUNDED_STACK_SIZE is that number rounded up to
368 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
369 both to put into the call insn and to generate explicit popping
372 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
373 It is zero if this call doesn't want a structure value.
375 NEXT_ARG_REG is the rtx that results from executing
376 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
377 just after all the args have had their registers assigned.
378 This could be whatever you like, but normally it is the first
379 arg-register beyond those used for args in this call,
380 or 0 if all the arg-registers are used in this call.
381 It is passed on to `gen_call' so you can put this info in the call insn.
383 VALREG is a hard register in which a value is returned,
384 or 0 if the call does not return a value.
386 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
387 the args to this call were processed.
388 We restore `inhibit_defer_pop' to that value.
390 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
391 denote registers used by the called function.
393 IS_CONST is true if this is a `const' call. */
396 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
397 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
398 call_fusage, ecf_flags)
400 tree fndecl ATTRIBUTE_UNUSED;
401 tree funtype ATTRIBUTE_UNUSED;
402 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
403 HOST_WIDE_INT rounded_stack_size;
404 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
407 int old_inhibit_defer_pop;
411 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
412 #if defined (HAVE_call) && defined (HAVE_call_value)
413 rtx struct_value_size_rtx = GEN_INT (struct_value_size);
416 #ifndef ACCUMULATE_OUTGOING_ARGS
417 int already_popped = 0;
418 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
421 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
422 and we don't want to load it into a register as an optimization,
423 because prepare_call_address already did it if it should be done. */
424 if (GET_CODE (funexp) != SYMBOL_REF)
425 funexp = memory_address (FUNCTION_MODE, funexp);
427 #ifndef ACCUMULATE_OUTGOING_ARGS
428 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
429 if ((ecf_flags & ECF_SIBCALL)
430 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
431 && (RETURN_POPS_ARGS (fndecl, funtype, stack_size) > 0
434 rtx n_pop = GEN_INT (RETURN_POPS_ARGS (fndecl, funtype, stack_size));
437 /* If this subroutine pops its own args, record that in the call insn
438 if possible, for the sake of frame pointer elimination. */
441 pat = gen_sibcall_value_pop (valreg,
442 gen_rtx_MEM (FUNCTION_MODE, funexp),
443 rounded_stack_size_rtx, next_arg_reg,
446 pat = gen_sibcall_pop (gen_rtx_MEM (FUNCTION_MODE, funexp),
447 rounded_stack_size_rtx, next_arg_reg, n_pop);
449 emit_call_insn (pat);
455 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
456 /* If the target has "call" or "call_value" insns, then prefer them
457 if no arguments are actually popped. If the target does not have
458 "call" or "call_value" insns, then we must use the popping versions
459 even if the call has no arguments to pop. */
460 #if defined (HAVE_call) && defined (HAVE_call_value)
461 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
464 if (HAVE_call_pop && HAVE_call_value_pop)
467 rtx n_pop = GEN_INT (n_popped);
470 /* If this subroutine pops its own args, record that in the call insn
471 if possible, for the sake of frame pointer elimination. */
474 pat = gen_call_value_pop (valreg,
475 gen_rtx_MEM (FUNCTION_MODE, funexp),
476 rounded_stack_size_rtx, next_arg_reg, n_pop);
478 pat = gen_call_pop (gen_rtx_MEM (FUNCTION_MODE, funexp),
479 rounded_stack_size_rtx, next_arg_reg, n_pop);
481 emit_call_insn (pat);
488 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
489 if ((ecf_flags & ECF_SIBCALL)
490 && HAVE_sibcall && HAVE_sibcall_value)
493 emit_call_insn (gen_sibcall_value (valreg,
494 gen_rtx_MEM (FUNCTION_MODE, funexp),
495 rounded_stack_size_rtx,
496 next_arg_reg, NULL_RTX));
498 emit_call_insn (gen_sibcall (gen_rtx_MEM (FUNCTION_MODE, funexp),
499 rounded_stack_size_rtx, next_arg_reg,
500 struct_value_size_rtx));
505 #if defined (HAVE_call) && defined (HAVE_call_value)
506 if (HAVE_call && HAVE_call_value)
509 emit_call_insn (gen_call_value (valreg,
510 gen_rtx_MEM (FUNCTION_MODE, funexp),
511 rounded_stack_size_rtx, next_arg_reg,
514 emit_call_insn (gen_call (gen_rtx_MEM (FUNCTION_MODE, funexp),
515 rounded_stack_size_rtx, next_arg_reg,
516 struct_value_size_rtx));
522 /* Find the CALL insn we just emitted. */
523 for (call_insn = get_last_insn ();
524 call_insn && GET_CODE (call_insn) != CALL_INSN;
525 call_insn = PREV_INSN (call_insn))
531 /* Put the register usage information on the CALL. If there is already
532 some usage information, put ours at the end. */
533 if (CALL_INSN_FUNCTION_USAGE (call_insn))
537 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
538 link = XEXP (link, 1))
541 XEXP (link, 1) = call_fusage;
544 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
546 /* If this is a const call, then set the insn's unchanging bit. */
547 if (ecf_flags & ECF_IS_CONST)
548 CONST_CALL_P (call_insn) = 1;
550 /* If this call can't throw, attach a REG_EH_REGION reg note to that
552 if (ecf_flags & ECF_NOTHROW)
553 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
554 REG_NOTES (call_insn));
556 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
558 /* Restore this now, so that we do defer pops for this call's args
559 if the context of the call as a whole permits. */
560 inhibit_defer_pop = old_inhibit_defer_pop;
562 #ifndef ACCUMULATE_OUTGOING_ARGS
563 /* If returning from the subroutine does not automatically pop the args,
564 we need an instruction to pop them sooner or later.
565 Perhaps do it now; perhaps just record how much space to pop later.
567 If returning from the subroutine does pop the args, indicate that the
568 stack pointer will be changed. */
570 /* The space for the args is no longer waiting for the call; either it
571 was popped by the call, or it'll be popped below. */
572 arg_space_so_far -= rounded_stack_size;
577 CALL_INSN_FUNCTION_USAGE (call_insn)
578 = gen_rtx_EXPR_LIST (VOIDmode,
579 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
580 CALL_INSN_FUNCTION_USAGE (call_insn));
581 rounded_stack_size -= n_popped;
582 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
585 if (rounded_stack_size != 0)
587 if (flag_defer_pop && inhibit_defer_pop == 0
588 && !(ecf_flags & ECF_IS_CONST))
589 pending_stack_adjust += rounded_stack_size;
591 adjust_stack (rounded_stack_size_rtx);
596 /* Determine if the function identified by NAME and FNDECL is one with
597 special properties we wish to know about.
599 For example, if the function might return more than one time (setjmp), then
600 set RETURNS_TWICE to a nonzero value.
602 Similarly set IS_LONGJMP for if the function is in the longjmp family.
604 Set IS_MALLOC for any of the standard memory allocation functions which
605 allocate from the heap.
607 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
608 space from the stack such as alloca. */
611 special_function_p (fndecl, returns_twice, is_longjmp, fork_or_exec,
612 is_malloc, may_be_alloca)
625 /* The function decl may have the `malloc' attribute. */
626 *is_malloc = fndecl && DECL_IS_MALLOC (fndecl);
629 && fndecl && DECL_NAME (fndecl)
630 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
631 /* Exclude functions not at the file scope, or not `extern',
632 since they are not the magic functions we would otherwise
634 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
636 char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
639 /* We assume that alloca will always be called by name. It
640 makes no sense to pass it as a pointer-to-function to
641 anything that does not understand its behavior. */
643 = (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
645 && ! strcmp (name, "alloca"))
646 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
648 && ! strcmp (name, "__builtin_alloca"))));
650 /* Disregard prefix _, __ or __x. */
653 if (name[1] == '_' && name[2] == 'x')
655 else if (name[1] == '_')
665 && (! strcmp (tname, "setjmp")
666 || ! strcmp (tname, "setjmp_syscall")))
668 && ! strcmp (tname, "sigsetjmp"))
670 && ! strcmp (tname, "savectx")));
672 && ! strcmp (tname, "siglongjmp"))
675 else if ((tname[0] == 'q' && tname[1] == 's'
676 && ! strcmp (tname, "qsetjmp"))
677 || (tname[0] == 'v' && tname[1] == 'f'
678 && ! strcmp (tname, "vfork")))
681 else if (tname[0] == 'l' && tname[1] == 'o'
682 && ! strcmp (tname, "longjmp"))
685 else if ((tname[0] == 'f' && tname[1] == 'o'
686 && ! strcmp (tname, "fork"))
687 /* Linux specific: __clone. check NAME to insist on the
688 leading underscores, to avoid polluting the ISO / POSIX
690 || (name[0] == '_' && name[1] == '_'
691 && ! strcmp (tname, "clone"))
692 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
693 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
695 || ((tname[5] == 'p' || tname[5] == 'e')
696 && tname[6] == '\0'))))
699 /* Do not add any more malloc-like functions to this list,
700 instead mark them as malloc functions using the malloc attribute.
701 Note, realloc is not suitable for attribute malloc since
702 it may return the same address across multiple calls.
703 C++ operator new is not suitable because it is not required
704 to return a unique pointer; indeed, the standard placement new
705 just returns its argument. */
706 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl))) == Pmode
707 && (! strcmp (tname, "malloc")
708 || ! strcmp (tname, "calloc")
709 || ! strcmp (tname, "strdup")))
714 /* Precompute all register parameters as described by ARGS, storing values
715 into fields within the ARGS array.
717 NUM_ACTUALS indicates the total number elements in the ARGS array.
719 Set REG_PARM_SEEN if we encounter a register parameter. */
722 precompute_register_parameters (num_actuals, args, reg_parm_seen)
724 struct arg_data *args;
731 for (i = 0; i < num_actuals; i++)
732 if (args[i].reg != 0 && ! args[i].pass_on_stack)
736 if (args[i].value == 0)
739 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
741 preserve_temp_slots (args[i].value);
744 /* ANSI doesn't require a sequence point here,
745 but PCC has one, so this will avoid some problems. */
749 /* If we are to promote the function arg to a wider mode,
752 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
754 = convert_modes (args[i].mode,
755 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
756 args[i].value, args[i].unsignedp);
758 /* If the value is expensive, and we are inside an appropriately
759 short loop, put the value into a pseudo and then put the pseudo
762 For small register classes, also do this if this call uses
763 register parameters. This is to avoid reload conflicts while
764 loading the parameters registers. */
766 if ((! (GET_CODE (args[i].value) == REG
767 || (GET_CODE (args[i].value) == SUBREG
768 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
769 && args[i].mode != BLKmode
770 && rtx_cost (args[i].value, SET) > 2
771 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
772 || preserve_subexpressions_p ()))
773 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
777 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
779 /* The argument list is the property of the called routine and it
780 may clobber it. If the fixed area has been used for previous
781 parameters, we must save and restore it. */
783 save_fixed_argument_area (reg_parm_stack_space, argblock,
784 low_to_save, high_to_save)
785 int reg_parm_stack_space;
791 rtx save_area = NULL_RTX;
793 /* Compute the boundary of the that needs to be saved, if any. */
794 #ifdef ARGS_GROW_DOWNWARD
795 for (i = 0; i < reg_parm_stack_space + 1; i++)
797 for (i = 0; i < reg_parm_stack_space; i++)
800 if (i >= highest_outgoing_arg_in_use
801 || stack_usage_map[i] == 0)
804 if (*low_to_save == -1)
810 if (*low_to_save >= 0)
812 int num_to_save = *high_to_save - *low_to_save + 1;
813 enum machine_mode save_mode
814 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
817 /* If we don't have the required alignment, must do this in BLKmode. */
818 if ((*low_to_save & (MIN (GET_MODE_SIZE (save_mode),
819 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
822 #ifdef ARGS_GROW_DOWNWARD
823 stack_area = gen_rtx_MEM (save_mode,
824 memory_address (save_mode,
825 plus_constant (argblock,
828 stack_area = gen_rtx_MEM (save_mode,
829 memory_address (save_mode,
830 plus_constant (argblock,
833 if (save_mode == BLKmode)
835 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
836 /* Cannot use emit_block_move here because it can be done by a library
837 call which in turn gets into this place again and deadly infinite
838 recursion happens. */
839 move_by_pieces (validize_mem (save_area), stack_area, num_to_save,
840 PARM_BOUNDARY / BITS_PER_UNIT);
844 save_area = gen_reg_rtx (save_mode);
845 emit_move_insn (save_area, stack_area);
852 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
858 enum machine_mode save_mode = GET_MODE (save_area);
859 #ifdef ARGS_GROW_DOWNWARD
861 = gen_rtx_MEM (save_mode,
862 memory_address (save_mode,
863 plus_constant (argblock,
867 = gen_rtx_MEM (save_mode,
868 memory_address (save_mode,
869 plus_constant (argblock,
873 if (save_mode != BLKmode)
874 emit_move_insn (stack_area, save_area);
876 /* Cannot use emit_block_move here because it can be done by a library
877 call which in turn gets into this place again and deadly infinite
878 recursion happens. */
879 move_by_pieces (stack_area, validize_mem (save_area),
880 high_to_save - low_to_save + 1,
881 PARM_BOUNDARY / BITS_PER_UNIT);
885 /* If any elements in ARGS refer to parameters that are to be passed in
886 registers, but not in memory, and whose alignment does not permit a
887 direct copy into registers. Copy the values into a group of pseudos
888 which we will later copy into the appropriate hard registers.
890 Pseudos for each unaligned argument will be stored into the array
891 args[argnum].aligned_regs. The caller is responsible for deallocating
892 the aligned_regs array if it is nonzero. */
895 store_unaligned_arguments_into_pseudos (args, num_actuals)
896 struct arg_data *args;
901 for (i = 0; i < num_actuals; i++)
902 if (args[i].reg != 0 && ! args[i].pass_on_stack
903 && args[i].mode == BLKmode
904 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
905 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
907 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
908 int big_endian_correction = 0;
910 args[i].n_aligned_regs
911 = args[i].partial ? args[i].partial
912 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
914 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
915 * args[i].n_aligned_regs);
917 /* Structures smaller than a word are aligned to the least
918 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
919 this means we must skip the empty high order bytes when
920 calculating the bit offset. */
921 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
922 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
924 for (j = 0; j < args[i].n_aligned_regs; j++)
926 rtx reg = gen_reg_rtx (word_mode);
927 rtx word = operand_subword_force (args[i].value, j, BLKmode);
928 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
929 int bitalign = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
931 args[i].aligned_regs[j] = reg;
933 /* There is no need to restrict this code to loading items
934 in TYPE_ALIGN sized hunks. The bitfield instructions can
935 load up entire word sized registers efficiently.
937 ??? This may not be needed anymore.
938 We use to emit a clobber here but that doesn't let later
939 passes optimize the instructions we emit. By storing 0 into
940 the register later passes know the first AND to zero out the
941 bitfield being set in the register is unnecessary. The store
942 of 0 will be deleted as will at least the first AND. */
944 emit_move_insn (reg, const0_rtx);
946 bytes -= bitsize / BITS_PER_UNIT;
947 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
948 extract_bit_field (word, bitsize, 0, 1,
951 bitalign / BITS_PER_UNIT,
953 bitalign / BITS_PER_UNIT, BITS_PER_WORD);
958 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
961 NUM_ACTUALS is the total number of parameters.
963 N_NAMED_ARGS is the total number of named arguments.
965 FNDECL is the tree code for the target of this call (if known)
967 ARGS_SO_FAR holds state needed by the target to know where to place
970 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
971 for arguments which are passed in registers.
973 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
974 and may be modified by this routine.
976 OLD_PENDING_ADJ, MUST_PREALLOCATE and IS_CONST are pointers to integer
977 flags which may may be modified by this routine. */
980 initialize_argument_information (num_actuals, args, args_size, n_named_args,
981 actparms, fndecl, args_so_far,
982 reg_parm_stack_space, old_stack_level,
983 old_pending_adj, must_preallocate, is_const)
984 int num_actuals ATTRIBUTE_UNUSED;
985 struct arg_data *args;
986 struct args_size *args_size;
987 int n_named_args ATTRIBUTE_UNUSED;
990 CUMULATIVE_ARGS *args_so_far;
991 int reg_parm_stack_space;
992 rtx *old_stack_level;
993 int *old_pending_adj;
994 int *must_preallocate;
997 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1000 /* Count arg position in order args appear. */
1003 struct args_size alignment_pad;
1007 args_size->constant = 0;
1010 /* In this loop, we consider args in the order they are written.
1011 We fill up ARGS from the front or from the back if necessary
1012 so that in any case the first arg to be pushed ends up at the front. */
1014 #ifdef PUSH_ARGS_REVERSED
1015 i = num_actuals - 1, inc = -1;
1016 /* In this case, must reverse order of args
1017 so that we compute and push the last arg first. */
1022 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1023 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1025 tree type = TREE_TYPE (TREE_VALUE (p));
1027 enum machine_mode mode;
1029 args[i].tree_value = TREE_VALUE (p);
1031 /* Replace erroneous argument with constant zero. */
1032 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1033 args[i].tree_value = integer_zero_node, type = integer_type_node;
1035 /* If TYPE is a transparent union, pass things the way we would
1036 pass the first field of the union. We have already verified that
1037 the modes are the same. */
1038 if (TYPE_TRANSPARENT_UNION (type))
1039 type = TREE_TYPE (TYPE_FIELDS (type));
1041 /* Decide where to pass this arg.
1043 args[i].reg is nonzero if all or part is passed in registers.
1045 args[i].partial is nonzero if part but not all is passed in registers,
1046 and the exact value says how many words are passed in registers.
1048 args[i].pass_on_stack is nonzero if the argument must at least be
1049 computed on the stack. It may then be loaded back into registers
1050 if args[i].reg is nonzero.
1052 These decisions are driven by the FUNCTION_... macros and must agree
1053 with those made by function.c. */
1055 /* See if this argument should be passed by invisible reference. */
1056 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1057 && contains_placeholder_p (TYPE_SIZE (type)))
1058 || TREE_ADDRESSABLE (type)
1059 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1060 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1061 type, argpos < n_named_args)
1065 /* If we're compiling a thunk, pass through invisible
1066 references instead of making a copy. */
1067 if (current_function_is_thunk
1068 #ifdef FUNCTION_ARG_CALLEE_COPIES
1069 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1070 type, argpos < n_named_args)
1071 /* If it's in a register, we must make a copy of it too. */
1072 /* ??? Is this a sufficient test? Is there a better one? */
1073 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1074 && REG_P (DECL_RTL (args[i].tree_value)))
1075 && ! TREE_ADDRESSABLE (type))
1079 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1080 new object from the argument. If we are passing by
1081 invisible reference, the callee will do that for us, so we
1082 can strip off the TARGET_EXPR. This is not always safe,
1083 but it is safe in the only case where this is a useful
1084 optimization; namely, when the argument is a plain object.
1085 In that case, the frontend is just asking the backend to
1086 make a bitwise copy of the argument. */
1088 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1089 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1090 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1091 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1093 args[i].tree_value = build1 (ADDR_EXPR,
1094 build_pointer_type (type),
1095 args[i].tree_value);
1096 type = build_pointer_type (type);
1100 /* We make a copy of the object and pass the address to the
1101 function being called. */
1104 if (!COMPLETE_TYPE_P (type)
1105 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1106 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1107 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1108 STACK_CHECK_MAX_VAR_SIZE))))
1110 /* This is a variable-sized object. Make space on the stack
1112 rtx size_rtx = expr_size (TREE_VALUE (p));
1114 if (*old_stack_level == 0)
1116 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1117 *old_pending_adj = pending_stack_adjust;
1118 pending_stack_adjust = 0;
1121 copy = gen_rtx_MEM (BLKmode,
1122 allocate_dynamic_stack_space (size_rtx,
1124 TYPE_ALIGN (type)));
1128 int size = int_size_in_bytes (type);
1129 copy = assign_stack_temp (TYPE_MODE (type), size, 0);
1132 MEM_SET_IN_STRUCT_P (copy, AGGREGATE_TYPE_P (type));
1134 store_expr (args[i].tree_value, copy, 0);
1137 args[i].tree_value = build1 (ADDR_EXPR,
1138 build_pointer_type (type),
1139 make_tree (type, copy));
1140 type = build_pointer_type (type);
1144 mode = TYPE_MODE (type);
1145 unsignedp = TREE_UNSIGNED (type);
1147 #ifdef PROMOTE_FUNCTION_ARGS
1148 mode = promote_mode (type, mode, &unsignedp, 1);
1151 args[i].unsignedp = unsignedp;
1152 args[i].mode = mode;
1153 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1154 argpos < n_named_args);
1155 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1158 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1159 argpos < n_named_args);
1162 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1164 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1165 it means that we are to pass this arg in the register(s) designated
1166 by the PARALLEL, but also to pass it in the stack. */
1167 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1168 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1169 args[i].pass_on_stack = 1;
1171 /* If this is an addressable type, we must preallocate the stack
1172 since we must evaluate the object into its final location.
1174 If this is to be passed in both registers and the stack, it is simpler
1176 if (TREE_ADDRESSABLE (type)
1177 || (args[i].pass_on_stack && args[i].reg != 0))
1178 *must_preallocate = 1;
1180 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1181 we cannot consider this function call constant. */
1182 if (TREE_ADDRESSABLE (type))
1185 /* Compute the stack-size of this argument. */
1186 if (args[i].reg == 0 || args[i].partial != 0
1187 || reg_parm_stack_space > 0
1188 || args[i].pass_on_stack)
1189 locate_and_pad_parm (mode, type,
1190 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1195 fndecl, args_size, &args[i].offset,
1196 &args[i].size, &alignment_pad);
1198 #ifndef ARGS_GROW_DOWNWARD
1199 args[i].slot_offset = *args_size;
1202 args[i].alignment_pad = alignment_pad;
1204 /* If a part of the arg was put into registers,
1205 don't include that part in the amount pushed. */
1206 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1207 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1208 / (PARM_BOUNDARY / BITS_PER_UNIT)
1209 * (PARM_BOUNDARY / BITS_PER_UNIT));
1211 /* Update ARGS_SIZE, the total stack space for args so far. */
1213 args_size->constant += args[i].size.constant;
1214 if (args[i].size.var)
1216 ADD_PARM_SIZE (*args_size, args[i].size.var);
1219 /* Since the slot offset points to the bottom of the slot,
1220 we must record it after incrementing if the args grow down. */
1221 #ifdef ARGS_GROW_DOWNWARD
1222 args[i].slot_offset = *args_size;
1224 args[i].slot_offset.constant = -args_size->constant;
1226 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1229 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1230 have been used, etc. */
1232 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1233 argpos < n_named_args);
1237 /* Update ARGS_SIZE to contain the total size for the argument block.
1238 Return the original constant component of the argument block's size.
1240 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1241 for arguments passed in registers. */
1244 compute_argument_block_size (reg_parm_stack_space, args_size,
1245 preferred_stack_boundary)
1246 int reg_parm_stack_space;
1247 struct args_size *args_size;
1248 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1250 int unadjusted_args_size = args_size->constant;
1252 /* Compute the actual size of the argument block required. The variable
1253 and constant sizes must be combined, the size may have to be rounded,
1254 and there may be a minimum required size. */
1258 args_size->var = ARGS_SIZE_TREE (*args_size);
1259 args_size->constant = 0;
1261 #ifdef PREFERRED_STACK_BOUNDARY
1262 preferred_stack_boundary /= BITS_PER_UNIT;
1263 if (preferred_stack_boundary > 1)
1264 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1267 if (reg_parm_stack_space > 0)
1270 = size_binop (MAX_EXPR, args_size->var,
1271 ssize_int (reg_parm_stack_space));
1273 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1274 /* The area corresponding to register parameters is not to count in
1275 the size of the block we need. So make the adjustment. */
1277 = size_binop (MINUS_EXPR, args_size->var,
1278 ssize_int (reg_parm_stack_space));
1284 #ifdef PREFERRED_STACK_BOUNDARY
1285 preferred_stack_boundary /= BITS_PER_UNIT;
1286 if (preferred_stack_boundary < 1)
1287 preferred_stack_boundary = 1;
1288 args_size->constant = (((args_size->constant
1290 + pending_stack_adjust
1291 + preferred_stack_boundary - 1)
1292 / preferred_stack_boundary
1293 * preferred_stack_boundary)
1295 - pending_stack_adjust);
1298 args_size->constant = MAX (args_size->constant,
1299 reg_parm_stack_space);
1301 #ifdef MAYBE_REG_PARM_STACK_SPACE
1302 if (reg_parm_stack_space == 0)
1303 args_size->constant = 0;
1306 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1307 args_size->constant -= reg_parm_stack_space;
1310 return unadjusted_args_size;
1313 /* Precompute parameters as needed for a function call.
1315 IS_CONST indicates the target function is a pure function.
1317 MUST_PREALLOCATE indicates that we must preallocate stack space for
1318 any stack arguments.
1320 NUM_ACTUALS is the number of arguments.
1322 ARGS is an array containing information for each argument; this routine
1323 fills in the INITIAL_VALUE and VALUE fields for each precomputed argument.
1325 ARGS_SIZE contains information about the size of the arg list. */
1328 precompute_arguments (is_const, must_preallocate, num_actuals, args, args_size)
1330 int must_preallocate;
1332 struct arg_data *args;
1333 struct args_size *args_size;
1337 /* If this function call is cse'able, precompute all the parameters.
1338 Note that if the parameter is constructed into a temporary, this will
1339 cause an additional copy because the parameter will be constructed
1340 into a temporary location and then copied into the outgoing arguments.
1341 If a parameter contains a call to alloca and this function uses the
1342 stack, precompute the parameter. */
1344 /* If we preallocated the stack space, and some arguments must be passed
1345 on the stack, then we must precompute any parameter which contains a
1346 function call which will store arguments on the stack.
1347 Otherwise, evaluating the parameter may clobber previous parameters
1348 which have already been stored into the stack. */
1350 for (i = 0; i < num_actuals; i++)
1352 || ((args_size->var != 0 || args_size->constant != 0)
1353 && calls_function (args[i].tree_value, 1))
1354 || (must_preallocate
1355 && (args_size->var != 0 || args_size->constant != 0)
1356 && calls_function (args[i].tree_value, 0)))
1358 /* If this is an addressable type, we cannot pre-evaluate it. */
1359 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1365 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1367 preserve_temp_slots (args[i].value);
1370 /* ANSI doesn't require a sequence point here,
1371 but PCC has one, so this will avoid some problems. */
1374 args[i].initial_value = args[i].value
1375 = protect_from_queue (args[i].value, 0);
1377 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) != args[i].mode)
1380 = convert_modes (args[i].mode,
1381 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1382 args[i].value, args[i].unsignedp);
1383 #ifdef PROMOTE_FOR_CALL_ONLY
1384 /* CSE will replace this only if it contains args[i].value
1385 pseudo, so convert it down to the declared mode using
1387 if (GET_CODE (args[i].value) == REG
1388 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1390 args[i].initial_value
1391 = gen_rtx_SUBREG (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1393 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1394 SUBREG_PROMOTED_UNSIGNED_P (args[i].initial_value)
1395 = args[i].unsignedp;
1402 /* Given the current state of MUST_PREALLOCATE and information about
1403 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1404 compute and return the final value for MUST_PREALLOCATE. */
1407 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1408 int must_preallocate;
1410 struct arg_data *args;
1411 struct args_size *args_size;
1413 /* See if we have or want to preallocate stack space.
1415 If we would have to push a partially-in-regs parm
1416 before other stack parms, preallocate stack space instead.
1418 If the size of some parm is not a multiple of the required stack
1419 alignment, we must preallocate.
1421 If the total size of arguments that would otherwise create a copy in
1422 a temporary (such as a CALL) is more than half the total argument list
1423 size, preallocation is faster.
1425 Another reason to preallocate is if we have a machine (like the m88k)
1426 where stack alignment is required to be maintained between every
1427 pair of insns, not just when the call is made. However, we assume here
1428 that such machines either do not have push insns (and hence preallocation
1429 would occur anyway) or the problem is taken care of with
1432 if (! must_preallocate)
1434 int partial_seen = 0;
1435 int copy_to_evaluate_size = 0;
1438 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1440 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1442 else if (partial_seen && args[i].reg == 0)
1443 must_preallocate = 1;
1445 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1446 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1447 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1448 || TREE_CODE (args[i].tree_value) == COND_EXPR
1449 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1450 copy_to_evaluate_size
1451 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1454 if (copy_to_evaluate_size * 2 >= args_size->constant
1455 && args_size->constant > 0)
1456 must_preallocate = 1;
1458 return must_preallocate;
1461 /* If we preallocated stack space, compute the address of each argument
1462 and store it into the ARGS array.
1464 We need not ensure it is a valid memory address here; it will be
1465 validized when it is used.
1467 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1470 compute_argument_addresses (args, argblock, num_actuals)
1471 struct arg_data *args;
1477 rtx arg_reg = argblock;
1478 int i, arg_offset = 0;
1480 if (GET_CODE (argblock) == PLUS)
1481 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1483 for (i = 0; i < num_actuals; i++)
1485 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1486 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1489 /* Skip this parm if it will not be passed on the stack. */
1490 if (! args[i].pass_on_stack && args[i].reg != 0)
1493 if (GET_CODE (offset) == CONST_INT)
1494 addr = plus_constant (arg_reg, INTVAL (offset));
1496 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1498 addr = plus_constant (addr, arg_offset);
1499 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1502 AGGREGATE_TYPE_P (TREE_TYPE (args[i].tree_value)));
1504 if (GET_CODE (slot_offset) == CONST_INT)
1505 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1507 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1509 addr = plus_constant (addr, arg_offset);
1510 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1515 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1516 in a call instruction.
1518 FNDECL is the tree node for the target function. For an indirect call
1519 FNDECL will be NULL_TREE.
1521 EXP is the CALL_EXPR for this call. */
1524 rtx_for_function_call (fndecl, exp)
1530 /* Get the function to call, in the form of RTL. */
1533 /* If this is the first use of the function, see if we need to
1534 make an external definition for it. */
1535 if (! TREE_USED (fndecl))
1537 assemble_external (fndecl);
1538 TREE_USED (fndecl) = 1;
1541 /* Get a SYMBOL_REF rtx for the function address. */
1542 funexp = XEXP (DECL_RTL (fndecl), 0);
1545 /* Generate an rtx (probably a pseudo-register) for the address. */
1550 expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1551 pop_temp_slots (); /* FUNEXP can't be BLKmode */
1553 /* Check the function is executable. */
1554 if (current_function_check_memory_usage)
1556 #ifdef POINTERS_EXTEND_UNSIGNED
1557 /* It might be OK to convert funexp in place, but there's
1558 a lot going on between here and when it happens naturally
1559 that this seems safer. */
1560 funaddr = convert_memory_address (Pmode, funexp);
1562 emit_library_call (chkr_check_exec_libfunc, 1,
1571 /* Do the register loads required for any wholly-register parms or any
1572 parms which are passed both on the stack and in a register. Their
1573 expressions were already evaluated.
1575 Mark all register-parms as living through the call, putting these USE
1576 insns in the CALL_INSN_FUNCTION_USAGE field. */
1579 load_register_parameters (args, num_actuals, call_fusage)
1580 struct arg_data *args;
1586 #ifdef LOAD_ARGS_REVERSED
1587 for (i = num_actuals - 1; i >= 0; i--)
1589 for (i = 0; i < num_actuals; i++)
1592 rtx reg = args[i].reg;
1593 int partial = args[i].partial;
1598 /* Set to non-negative if must move a word at a time, even if just
1599 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1600 we just use a normal move insn. This value can be zero if the
1601 argument is a zero size structure with no fields. */
1602 nregs = (partial ? partial
1603 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1604 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1605 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1608 /* Handle calls that pass values in multiple non-contiguous
1609 locations. The Irix 6 ABI has examples of this. */
1611 if (GET_CODE (reg) == PARALLEL)
1613 emit_group_load (reg, args[i].value,
1614 int_size_in_bytes (TREE_TYPE (args[i].tree_value)),
1615 (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1619 /* If simple case, just do move. If normal partial, store_one_arg
1620 has already loaded the register for us. In all other cases,
1621 load the register(s) from memory. */
1623 else if (nregs == -1)
1624 emit_move_insn (reg, args[i].value);
1626 /* If we have pre-computed the values to put in the registers in
1627 the case of non-aligned structures, copy them in now. */
1629 else if (args[i].n_aligned_regs != 0)
1630 for (j = 0; j < args[i].n_aligned_regs; j++)
1631 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1632 args[i].aligned_regs[j]);
1634 else if (partial == 0 || args[i].pass_on_stack)
1635 move_block_to_reg (REGNO (reg),
1636 validize_mem (args[i].value), nregs,
1639 /* Handle calls that pass values in multiple non-contiguous
1640 locations. The Irix 6 ABI has examples of this. */
1641 if (GET_CODE (reg) == PARALLEL)
1642 use_group_regs (call_fusage, reg);
1643 else if (nregs == -1)
1644 use_reg (call_fusage, reg);
1646 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1651 /* Generate all the code for a function call
1652 and return an rtx for its value.
1653 Store the value in TARGET (specified as an rtx) if convenient.
1654 If the value is stored in TARGET then TARGET is returned.
1655 If IGNORE is nonzero, then we ignore the value of the function call. */
1658 expand_call (exp, target, ignore)
1663 /* Nonzero if we are currently expanding a call. */
1664 static int currently_expanding_call = 0;
1666 /* List of actual parameters. */
1667 tree actparms = TREE_OPERAND (exp, 1);
1668 /* RTX for the function to be called. */
1670 /* Sequence of insns to perform a tail recursive "call". */
1671 rtx tail_recursion_insns = NULL_RTX;
1672 /* Sequence of insns to perform a normal "call". */
1673 rtx normal_call_insns = NULL_RTX;
1674 /* Sequence of insns to perform a tail recursive "call". */
1675 rtx tail_call_insns = NULL_RTX;
1676 /* Data type of the function. */
1678 /* Declaration of the function being called,
1679 or 0 if the function is computed (not known by name). */
1682 #ifdef ACCUMULATE_OUTGOING_ARGS
1686 int safe_for_reeval;
1689 /* Register in which non-BLKmode value will be returned,
1690 or 0 if no value or if value is BLKmode. */
1692 /* Address where we should return a BLKmode value;
1693 0 if value not BLKmode. */
1694 rtx structure_value_addr = 0;
1695 /* Nonzero if that address is being passed by treating it as
1696 an extra, implicit first parameter. Otherwise,
1697 it is passed by being copied directly into struct_value_rtx. */
1698 int structure_value_addr_parm = 0;
1699 /* Size of aggregate value wanted, or zero if none wanted
1700 or if we are using the non-reentrant PCC calling convention
1701 or expecting the value in registers. */
1702 HOST_WIDE_INT struct_value_size = 0;
1703 /* Nonzero if called function returns an aggregate in memory PCC style,
1704 by returning the address of where to find it. */
1705 int pcc_struct_value = 0;
1707 /* Number of actual parameters in this call, including struct value addr. */
1709 /* Number of named args. Args after this are anonymous ones
1710 and they must all go on the stack. */
1713 /* Vector of information about each argument.
1714 Arguments are numbered in the order they will be pushed,
1715 not the order they are written. */
1716 struct arg_data *args;
1718 /* Total size in bytes of all the stack-parms scanned so far. */
1719 struct args_size args_size;
1720 /* Size of arguments before any adjustments (such as rounding). */
1721 int unadjusted_args_size;
1722 /* Data on reg parms scanned so far. */
1723 CUMULATIVE_ARGS args_so_far;
1724 /* Nonzero if a reg parm has been scanned. */
1726 /* Nonzero if this is an indirect function call. */
1728 /* Nonzero if we must avoid push-insns in the args for this call.
1729 If stack space is allocated for register parameters, but not by the
1730 caller, then it is preallocated in the fixed part of the stack frame.
1731 So the entire argument block must then be preallocated (i.e., we
1732 ignore PUSH_ROUNDING in that case). */
1734 #ifdef PUSH_ROUNDING
1735 int must_preallocate = 0;
1737 int must_preallocate = 1;
1740 /* Size of the stack reserved for parameter registers. */
1741 int reg_parm_stack_space = 0;
1743 /* Address of space preallocated for stack parms
1744 (on machines that lack push insns), or 0 if space not preallocated. */
1747 /* Nonzero if it is plausible that this is a call to alloca. */
1749 /* Nonzero if this is a call to malloc or a related function. */
1751 /* Nonzero if this is a call to setjmp or a related function. */
1753 /* Nonzero if this is a call to `longjmp'. */
1755 /* Nonzero if this is a syscall that makes a new process in the image of
1758 /* Nonzero if this is a call to an inline function. */
1759 int is_integrable = 0;
1760 /* Nonzero if this is a call to a `const' function.
1761 Note that only explicitly named functions are handled as `const' here. */
1763 /* Nonzero if this is a call to a `volatile' function. */
1764 int is_volatile = 0;
1765 /* Nonzero if this is a call to a function that won't throw an exception. */
1766 int nothrow = TREE_NOTHROW (exp);
1767 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
1768 /* Define the boundary of the register parm stack space that needs to be
1770 int low_to_save = -1, high_to_save;
1771 rtx save_area = 0; /* Place that it is saved */
1774 #ifdef ACCUMULATE_OUTGOING_ARGS
1775 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
1776 char *initial_stack_usage_map = stack_usage_map;
1777 int old_stack_arg_under_construction = 0;
1780 rtx old_stack_level = 0;
1781 int old_pending_adj = 0;
1782 int old_inhibit_defer_pop = inhibit_defer_pop;
1786 int preferred_stack_boundary;
1788 /* The value of the function call can be put in a hard register. But
1789 if -fcheck-memory-usage, code which invokes functions (and thus
1790 damages some hard registers) can be inserted before using the value.
1791 So, target is always a pseudo-register in that case. */
1792 if (current_function_check_memory_usage)
1795 /* See if we can find a DECL-node for the actual function.
1796 As a result, decide whether this is a call to an integrable function. */
1798 p = TREE_OPERAND (exp, 0);
1799 if (TREE_CODE (p) == ADDR_EXPR)
1801 fndecl = TREE_OPERAND (p, 0);
1802 if (TREE_CODE (fndecl) != FUNCTION_DECL)
1807 && fndecl != current_function_decl
1808 && DECL_INLINE (fndecl)
1809 && DECL_SAVED_INSNS (fndecl)
1810 && DECL_SAVED_INSNS (fndecl)->inlinable)
1812 else if (! TREE_ADDRESSABLE (fndecl))
1814 /* In case this function later becomes inlinable,
1815 record that there was already a non-inline call to it.
1817 Use abstraction instead of setting TREE_ADDRESSABLE
1819 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1822 warning_with_decl (fndecl, "can't inline call to `%s'");
1823 warning ("called from here");
1825 mark_addressable (fndecl);
1828 if (TREE_READONLY (fndecl) && ! TREE_THIS_VOLATILE (fndecl)
1829 && TYPE_MODE (TREE_TYPE (exp)) != VOIDmode)
1832 if (TREE_THIS_VOLATILE (fndecl))
1835 if (TREE_NOTHROW (fndecl))
1840 /* If we don't have specific function to call, see if we have a
1841 constant or `noreturn' function from the type. */
1844 is_const = TREE_READONLY (TREE_TYPE (TREE_TYPE (p)));
1845 is_volatile = TREE_THIS_VOLATILE (TREE_TYPE (TREE_TYPE (p)));
1848 #ifdef REG_PARM_STACK_SPACE
1849 #ifdef MAYBE_REG_PARM_STACK_SPACE
1850 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1852 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1856 #if defined(PUSH_ROUNDING) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1857 if (reg_parm_stack_space > 0)
1858 must_preallocate = 1;
1861 /* Warn if this value is an aggregate type,
1862 regardless of which calling convention we are using for it. */
1863 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
1864 warning ("function call has aggregate value");
1866 /* Set up a place to return a structure. */
1868 /* Cater to broken compilers. */
1869 if (aggregate_value_p (exp))
1871 /* This call returns a big structure. */
1874 #ifdef PCC_STATIC_STRUCT_RETURN
1876 pcc_struct_value = 1;
1877 /* Easier than making that case work right. */
1880 /* In case this is a static function, note that it has been
1882 if (! TREE_ADDRESSABLE (fndecl))
1883 mark_addressable (fndecl);
1887 #else /* not PCC_STATIC_STRUCT_RETURN */
1889 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
1891 if (target && GET_CODE (target) == MEM)
1892 structure_value_addr = XEXP (target, 0);
1895 /* Assign a temporary to hold the value. */
1898 /* For variable-sized objects, we must be called with a target
1899 specified. If we were to allocate space on the stack here,
1900 we would have no way of knowing when to free it. */
1902 if (struct_value_size < 0)
1905 /* This DECL is just something to feed to mark_addressable;
1906 it doesn't get pushed. */
1907 d = build_decl (VAR_DECL, NULL_TREE, TREE_TYPE (exp));
1908 DECL_RTL (d) = assign_temp (TREE_TYPE (exp), 1, 0, 1);
1909 mark_addressable (d);
1910 mark_temp_addr_taken (DECL_RTL (d));
1911 structure_value_addr = XEXP (DECL_RTL (d), 0);
1916 #endif /* not PCC_STATIC_STRUCT_RETURN */
1919 /* If called function is inline, try to integrate it. */
1925 #ifdef ACCUMULATE_OUTGOING_ARGS
1926 before_call = get_last_insn ();
1929 temp = expand_inline_function (fndecl, actparms, target,
1930 ignore, TREE_TYPE (exp),
1931 structure_value_addr);
1933 /* If inlining succeeded, return. */
1934 if (temp != (rtx) (HOST_WIDE_INT) -1)
1936 #ifdef ACCUMULATE_OUTGOING_ARGS
1937 /* If the outgoing argument list must be preserved, push
1938 the stack before executing the inlined function if it
1941 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1942 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1945 if (stack_arg_under_construction || i >= 0)
1948 = before_call ? NEXT_INSN (before_call) : get_insns ();
1949 rtx insn = NULL_RTX, seq;
1951 /* Look for a call in the inline function code.
1952 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1953 nonzero then there is a call and it is not necessary
1954 to scan the insns. */
1956 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1957 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1958 if (GET_CODE (insn) == CALL_INSN)
1963 /* Reserve enough stack space so that the largest
1964 argument list of any function call in the inline
1965 function does not overlap the argument list being
1966 evaluated. This is usually an overestimate because
1967 allocate_dynamic_stack_space reserves space for an
1968 outgoing argument list in addition to the requested
1969 space, but there is no way to ask for stack space such
1970 that an argument list of a certain length can be
1973 Add the stack space reserved for register arguments, if
1974 any, in the inline function. What is really needed is the
1975 largest value of reg_parm_stack_space in the inline
1976 function, but that is not available. Using the current
1977 value of reg_parm_stack_space is wrong, but gives
1978 correct results on all supported machines. */
1980 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1981 + reg_parm_stack_space);
1984 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1985 allocate_dynamic_stack_space (GEN_INT (adjust),
1986 NULL_RTX, BITS_PER_UNIT);
1989 emit_insns_before (seq, first_insn);
1990 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1995 /* If the result is equivalent to TARGET, return TARGET to simplify
1996 checks in store_expr. They can be equivalent but not equal in the
1997 case of a function that returns BLKmode. */
1998 if (temp != target && rtx_equal_p (temp, target))
2003 /* If inlining failed, mark FNDECL as needing to be compiled
2004 separately after all. If function was declared inline,
2006 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2007 && optimize > 0 && ! TREE_ADDRESSABLE (fndecl))
2009 warning_with_decl (fndecl, "inlining failed in call to `%s'");
2010 warning ("called from here");
2012 mark_addressable (fndecl);
2015 currently_expanding_call++;
2017 /* If we're considering tail recursion optimizations, verify that the
2018 arguments are safe for re-evaluation. If we can unsave them, wrap
2019 each argument in an UNSAVE_EXPR. */
2021 safe_for_reeval = 0;
2023 && currently_expanding_call == 1
2024 && stmt_loop_nest_empty ()
2025 && ! any_pending_cleanups (1))
2027 /* Verify that each argument is safe for re-evaluation. */
2028 for (p = actparms; p; p = TREE_CHAIN (p))
2029 if (! safe_for_unsave (TREE_VALUE (p)))
2034 tree new_actparms = NULL_TREE, q;
2036 for (p = actparms; p ; p = TREE_CHAIN (p))
2038 tree np = build_tree_list (TREE_PURPOSE (p),
2039 unsave_expr (TREE_VALUE (p)));
2041 TREE_CHAIN (q) = np;
2047 actparms = new_actparms;
2048 safe_for_reeval = 1;
2052 /* Generate a tail recursion sequence when calling ourselves. */
2055 && TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
2056 && TREE_OPERAND (TREE_OPERAND (exp, 0), 0) == current_function_decl)
2058 /* We want to emit any pending stack adjustments before the tail
2059 recursion "call". That way we know any adjustment after the tail
2060 recursion call can be ignored if we indeed use the tail recursion
2062 int save_pending_stack_adjust = pending_stack_adjust;
2065 /* Use a new sequence to hold any RTL we generate. We do not even
2066 know if we will use this RTL yet. The final decision can not be
2067 made until after RTL generation for the entire function is
2069 push_to_sequence (0);
2071 /* Emit the pending stack adjustments before we expand any arguments. */
2072 do_pending_stack_adjust ();
2074 optimize_tail_recursion (exp, get_last_insn ());
2076 last = get_last_insn ();
2077 tail_recursion_insns = get_insns ();
2080 /* If the last insn on the tail recursion sequence is not a
2081 BARRIER, then tail recursion optimization failed. */
2082 if (last == NULL_RTX || GET_CODE (last) != BARRIER)
2083 tail_recursion_insns = NULL_RTX;
2085 /* Restore the original pending stack adjustment for the sibling and
2086 normal call cases below. */
2087 pending_stack_adjust = save_pending_stack_adjust;
2090 function_call_count++;
2092 if (fndecl && DECL_NAME (fndecl))
2093 name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
2095 #ifdef PREFERRED_STACK_BOUNDARY
2096 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2098 preferred_stack_boundary = STACK_BOUNDARY;
2101 /* Ensure current function's preferred stack boundary is at least
2102 what we need. We don't have to increase alignment for recursive
2104 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2105 && fndecl != current_function_decl)
2106 cfun->preferred_stack_boundary = preferred_stack_boundary;
2108 /* See if this is a call to a function that can return more than once
2109 or a call to longjmp or malloc. */
2110 special_function_p (fndecl, &returns_twice, &is_longjmp, &fork_or_exec,
2111 &is_malloc, &may_be_alloca);
2114 current_function_calls_alloca = 1;
2116 /* Operand 0 is a pointer-to-function; get the type of the function. */
2117 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
2118 if (! POINTER_TYPE_P (funtype))
2120 funtype = TREE_TYPE (funtype);
2122 /* We want to make two insn chains; one for a sibling call, the other
2123 for a normal call. We will select one of the two chains after
2124 initial RTL generation is complete. */
2125 for (pass = 0; pass < 2; pass++)
2127 int sibcall_failure = 0;
2128 /* We want to emit ay pending stack adjustments before the tail
2129 recursion "call". That way we know any adjustment after the tail
2130 recursion call can be ignored if we indeed use the tail recursion
2132 int save_pending_stack_adjust;
2138 /* Various reasons we can not use a sibling call. */
2139 if (! safe_for_reeval
2140 #ifdef HAVE_sibcall_epilogue
2141 || ! HAVE_sibcall_epilogue
2145 /* The structure value address is used and modified in the
2146 loop below. It does not seem worth the effort to save and
2147 restore it as a state variable since few optimizable
2148 sibling calls will return a structure. */
2149 || structure_value_addr != NULL_RTX
2150 /* If the register holding the address is a callee saved
2151 register, then we lose. We have no way to prevent that,
2152 so we only allow calls to named functions. */
2153 || fndecl == NULL_TREE
2154 || ! FUNCTION_OK_FOR_SIBCALL (fndecl))
2157 /* We know at this point that there are not currently any
2158 pending cleanups. If, however, in the process of evaluating
2159 the arguments we were to create some, we'll need to be
2160 able to get rid of them. */
2161 expand_start_target_temps ();
2163 /* State variables we need to save and restore between
2165 save_pending_stack_adjust = pending_stack_adjust;
2168 /* Other state variables that we must reinitialize each time
2169 through the loop (that are not initialized by the loop itself. */
2173 /* Start a new sequence for the normal call case.
2175 From this point on, if the sibling call fails, we want to set
2176 sibcall_failure instead of continuing the loop. */
2179 /* When calling a const function, we must pop the stack args right away,
2180 so that the pop is deleted or moved with the call. */
2184 /* Don't let pending stack adjusts add up to too much.
2185 Also, do all pending adjustments now if there is any chance
2186 this might be a call to alloca or if we are expanding a sibling
2188 if (pending_stack_adjust >= 32
2189 || (pending_stack_adjust > 0 && may_be_alloca)
2191 do_pending_stack_adjust ();
2193 if (profile_arc_flag && fork_or_exec)
2195 /* A fork duplicates the profile information, and an exec discards
2196 it. We can't rely on fork/exec to be paired. So write out the
2197 profile information we have gathered so far, and clear it. */
2198 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2199 is subject to race conditions, just as with multithreaded
2202 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__bb_fork_func"), 0,
2206 /* Push the temporary stack slot level so that we can free any
2207 temporaries we make. */
2210 /* Start updating where the next arg would go.
2212 On some machines (such as the PA) indirect calls have a different
2213 calling convention than normal calls. The last argument in
2214 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2216 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
2218 /* If struct_value_rtx is 0, it means pass the address
2219 as if it were an extra parameter. */
2220 if (structure_value_addr && struct_value_rtx == 0)
2222 /* If structure_value_addr is a REG other than
2223 virtual_outgoing_args_rtx, we can use always use it. If it
2224 is not a REG, we must always copy it into a register.
2225 If it is virtual_outgoing_args_rtx, we must copy it to another
2226 register in some cases. */
2227 rtx temp = (GET_CODE (structure_value_addr) != REG
2228 #ifdef ACCUMULATE_OUTGOING_ARGS
2229 || (stack_arg_under_construction
2230 && structure_value_addr == virtual_outgoing_args_rtx)
2232 ? copy_addr_to_reg (structure_value_addr)
2233 : structure_value_addr);
2236 = tree_cons (error_mark_node,
2237 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2240 structure_value_addr_parm = 1;
2243 /* Count the arguments and set NUM_ACTUALS. */
2244 for (p = actparms, i = 0; p; p = TREE_CHAIN (p)) i++;
2247 /* Compute number of named args.
2248 Normally, don't include the last named arg if anonymous args follow.
2249 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2250 (If no anonymous args follow, the result of list_length is actually
2251 one too large. This is harmless.)
2253 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2254 zero, this machine will be able to place unnamed args that were
2255 passed in registers into the stack. So treat all args as named.
2256 This allows the insns emitting for a specific argument list to be
2257 independent of the function declaration.
2259 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2260 reliable way to pass unnamed args in registers, so we must force
2261 them into memory. */
2263 if ((STRICT_ARGUMENT_NAMING
2264 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2265 && TYPE_ARG_TYPES (funtype) != 0)
2267 = (list_length (TYPE_ARG_TYPES (funtype))
2268 /* Don't include the last named arg. */
2269 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2270 /* Count the struct value address, if it is passed as a parm. */
2271 + structure_value_addr_parm);
2273 /* If we know nothing, treat all args as named. */
2274 n_named_args = num_actuals;
2276 /* Make a vector to hold all the information about each arg. */
2277 args = (struct arg_data *) alloca (num_actuals
2278 * sizeof (struct arg_data));
2279 bzero ((char *) args, num_actuals * sizeof (struct arg_data));
2281 /* Build up entries inthe ARGS array, compute the size of the arguments
2282 into ARGS_SIZE, etc. */
2283 initialize_argument_information (num_actuals, args, &args_size,
2284 n_named_args, actparms, fndecl,
2285 &args_so_far, reg_parm_stack_space,
2286 &old_stack_level, &old_pending_adj,
2287 &must_preallocate, &is_const);
2289 #ifdef FINAL_REG_PARM_STACK_SPACE
2290 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2296 /* If this function requires a variable-sized argument list, don't
2297 try to make a cse'able block for this call. We may be able to
2298 do this eventually, but it is too complicated to keep track of
2299 what insns go in the cse'able block and which don't.
2301 Also do not make a sibling call. */
2304 must_preallocate = 1;
2305 sibcall_failure = 1;
2308 /* Compute the actual size of the argument block required. The variable
2309 and constant sizes must be combined, the size may have to be rounded,
2310 and there may be a minimum required size. When generating a sibcall
2311 pattern, do not round up, since we'll be re-using whatever space our
2313 unadjusted_args_size
2314 = compute_argument_block_size (reg_parm_stack_space, &args_size,
2316 : preferred_stack_boundary));
2318 /* If the callee pops its own arguments, then it must pop exactly
2319 the same number of arguments as the current function. */
2320 if (RETURN_POPS_ARGS (fndecl, funtype, unadjusted_args_size)
2321 != RETURN_POPS_ARGS (current_function_decl,
2322 TREE_TYPE (current_function_decl),
2323 current_function_args_size))
2324 sibcall_failure = 1;
2326 /* Now make final decision about preallocating stack space. */
2327 must_preallocate = finalize_must_preallocate (must_preallocate,
2331 /* If the structure value address will reference the stack pointer, we
2332 must stabilize it. We don't need to do this if we know that we are
2333 not going to adjust the stack pointer in processing this call. */
2335 if (structure_value_addr
2336 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2337 || reg_mentioned_p (virtual_outgoing_args_rtx,
2338 structure_value_addr))
2340 #ifndef ACCUMULATE_OUTGOING_ARGS
2341 || args_size.constant
2344 structure_value_addr = copy_to_reg (structure_value_addr);
2346 /* Precompute any arguments as needed. */
2347 precompute_arguments (is_const, must_preallocate, num_actuals,
2350 /* Now we are about to start emitting insns that can be deleted
2351 if a libcall is deleted. */
2352 if (is_const || is_malloc)
2355 /* If we have no actual push instructions, or shouldn't use them,
2356 make space for all args right now. */
2358 if (args_size.var != 0)
2360 if (old_stack_level == 0)
2362 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2363 old_pending_adj = pending_stack_adjust;
2364 pending_stack_adjust = 0;
2365 #ifdef ACCUMULATE_OUTGOING_ARGS
2366 /* stack_arg_under_construction says whether a stack arg is
2367 being constructed at the old stack level. Pushing the stack
2368 gets a clean outgoing argument block. */
2369 old_stack_arg_under_construction = stack_arg_under_construction;
2370 stack_arg_under_construction = 0;
2373 argblock = push_block (ARGS_SIZE_RTX (args_size), 0, 0);
2377 /* Note that we must go through the motions of allocating an argument
2378 block even if the size is zero because we may be storing args
2379 in the area reserved for register arguments, which may be part of
2382 int needed = args_size.constant;
2384 /* Store the maximum argument space used. It will be pushed by
2385 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2388 if (needed > current_function_outgoing_args_size)
2389 current_function_outgoing_args_size = needed;
2391 if (must_preallocate)
2393 #ifdef ACCUMULATE_OUTGOING_ARGS
2394 /* Since the stack pointer will never be pushed, it is possible
2395 for the evaluation of a parm to clobber something we have
2396 already written to the stack. Since most function calls on
2397 RISC machines do not use the stack, this is uncommon, but
2398 must work correctly.
2400 Therefore, we save any area of the stack that was already
2401 written and that we are using. Here we set up to do this by
2402 making a new stack usage map from the old one. The actual
2403 save will be done by store_one_arg.
2405 Another approach might be to try to reorder the argument
2406 evaluations to avoid this conflicting stack usage. */
2408 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2409 /* Since we will be writing into the entire argument area, the
2410 map must be allocated for its entire size, not just the part
2411 that is the responsibility of the caller. */
2412 needed += reg_parm_stack_space;
2415 #ifdef ARGS_GROW_DOWNWARD
2416 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2419 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2422 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
2424 if (initial_highest_arg_in_use)
2425 bcopy (initial_stack_usage_map, stack_usage_map,
2426 initial_highest_arg_in_use);
2428 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2429 bzero (&stack_usage_map[initial_highest_arg_in_use],
2430 (highest_outgoing_arg_in_use
2431 - initial_highest_arg_in_use));
2434 /* The address of the outgoing argument list must not be copied
2435 to a register here, because argblock would be left pointing
2436 to the wrong place after the call to
2437 allocate_dynamic_stack_space below. */
2439 argblock = virtual_outgoing_args_rtx;
2441 #else /* not ACCUMULATE_OUTGOING_ARGS */
2442 if (inhibit_defer_pop == 0)
2444 /* Try to reuse some or all of the pending_stack_adjust
2445 to get this space. Maybe we can avoid any pushing. */
2446 if (needed > pending_stack_adjust)
2448 needed -= pending_stack_adjust;
2449 pending_stack_adjust = 0;
2453 pending_stack_adjust -= needed;
2457 /* Special case this because overhead of `push_block' in this
2458 case is non-trivial. */
2460 argblock = virtual_outgoing_args_rtx;
2462 argblock = push_block (GEN_INT (needed), 0, 0);
2464 /* We only really need to call `copy_to_reg' in the case where
2465 push insns are going to be used to pass ARGBLOCK to a function
2466 call in ARGS. In that case, the stack pointer changes value
2467 from the allocation point to the call point, and hence
2468 the value of VIRTUAL_OUTGOING_ARGS_RTX changes as well.
2469 But might as well always do it. */
2470 argblock = copy_to_reg (argblock);
2471 #endif /* not ACCUMULATE_OUTGOING_ARGS */
2475 /* The argument block when performing a sibling call is the
2476 incoming argument block. */
2479 rtx temp = plus_constant (arg_pointer_rtx,
2480 FIRST_PARM_OFFSET (current_function_decl));
2481 argblock = force_reg (Pmode, force_operand (temp, NULL_RTX));
2484 #ifdef ACCUMULATE_OUTGOING_ARGS
2485 /* The save/restore code in store_one_arg handles all cases except one:
2486 a constructor call (including a C function returning a BLKmode struct)
2487 to initialize an argument. */
2488 if (stack_arg_under_construction)
2490 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2491 rtx push_size = GEN_INT (reg_parm_stack_space + args_size.constant);
2493 rtx push_size = GEN_INT (args_size.constant);
2495 if (old_stack_level == 0)
2497 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2498 old_pending_adj = pending_stack_adjust;
2499 pending_stack_adjust = 0;
2500 /* stack_arg_under_construction says whether a stack arg is
2501 being constructed at the old stack level. Pushing the stack
2502 gets a clean outgoing argument block. */
2503 old_stack_arg_under_construction = stack_arg_under_construction;
2504 stack_arg_under_construction = 0;
2505 /* Make a new map for the new argument list. */
2506 stack_usage_map = (char *)alloca (highest_outgoing_arg_in_use);
2507 bzero (stack_usage_map, highest_outgoing_arg_in_use);
2508 highest_outgoing_arg_in_use = 0;
2510 allocate_dynamic_stack_space (push_size, NULL_RTX, BITS_PER_UNIT);
2512 /* If argument evaluation might modify the stack pointer, copy the
2513 address of the argument list to a register. */
2514 for (i = 0; i < num_actuals; i++)
2515 if (args[i].pass_on_stack)
2517 argblock = copy_addr_to_reg (argblock);
2522 compute_argument_addresses (args, argblock, num_actuals);
2524 #ifdef PUSH_ARGS_REVERSED
2525 #ifdef PREFERRED_STACK_BOUNDARY
2526 /* If we push args individually in reverse order, perform stack alignment
2527 before the first push (the last arg). */
2528 if (args_size.constant != unadjusted_args_size)
2530 /* When the stack adjustment is pending, we get better code
2531 by combining the adjustments. */
2532 if (pending_stack_adjust && ! is_const
2533 && ! inhibit_defer_pop)
2535 args_size.constant = (unadjusted_args_size
2536 + ((pending_stack_adjust
2537 + args_size.constant
2539 - unadjusted_args_size)
2540 % (preferred_stack_boundary
2542 pending_stack_adjust -= (args_size.constant
2543 - unadjusted_args_size);
2544 do_pending_stack_adjust ();
2546 else if (argblock == 0)
2547 anti_adjust_stack (GEN_INT (args_size.constant
2548 - unadjusted_args_size));
2549 arg_space_so_far += args_size.constant - unadjusted_args_size;
2551 /* Now that the stack is properly aligned, pops can't safely
2552 be deferred during the evaluation of the arguments. */
2558 /* Don't try to defer pops if preallocating, not even from the first arg,
2559 since ARGBLOCK probably refers to the SP. */
2563 funexp = rtx_for_function_call (fndecl, exp);
2565 /* Figure out the register where the value, if any, will come back. */
2567 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2568 && ! structure_value_addr)
2570 if (pcc_struct_value)
2571 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2574 valreg = hard_function_value (TREE_TYPE (exp), fndecl, 0);
2577 /* Precompute all register parameters. It isn't safe to compute anything
2578 once we have started filling any specific hard regs. */
2579 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2581 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
2582 /* Save the fixed argument area if it's part of the caller's frame and
2583 is clobbered by argument setup for this call. */
2584 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2585 &low_to_save, &high_to_save);
2588 /* Now store (and compute if necessary) all non-register parms.
2589 These come before register parms, since they can require block-moves,
2590 which could clobber the registers used for register parms.
2591 Parms which have partial registers are not stored here,
2592 but we do preallocate space here if they want that. */
2594 for (i = 0; i < num_actuals; i++)
2595 if (args[i].reg == 0 || args[i].pass_on_stack)
2596 store_one_arg (&args[i], argblock, may_be_alloca,
2597 args_size.var != 0, reg_parm_stack_space);
2599 /* If we have a parm that is passed in registers but not in memory
2600 and whose alignment does not permit a direct copy into registers,
2601 make a group of pseudos that correspond to each register that we
2603 if (STRICT_ALIGNMENT)
2604 store_unaligned_arguments_into_pseudos (args, num_actuals);
2606 /* Now store any partially-in-registers parm.
2607 This is the last place a block-move can happen. */
2609 for (i = 0; i < num_actuals; i++)
2610 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2611 store_one_arg (&args[i], argblock, may_be_alloca,
2612 args_size.var != 0, reg_parm_stack_space);
2614 #ifndef PUSH_ARGS_REVERSED
2615 #ifdef PREFERRED_STACK_BOUNDARY
2616 /* If we pushed args in forward order, perform stack alignment
2617 after pushing the last arg. */
2618 /* ??? Fix for arg_space_so_far. */
2620 anti_adjust_stack (GEN_INT (args_size.constant
2621 - unadjusted_args_size));
2625 /* If register arguments require space on the stack and stack space
2626 was not preallocated, allocate stack space here for arguments
2627 passed in registers. */
2628 #if ! defined(ACCUMULATE_OUTGOING_ARGS) && defined(OUTGOING_REG_PARM_STACK_SPACE)
2629 if (must_preallocate == 0 && reg_parm_stack_space > 0)
2630 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
2633 /* Pass the function the address in which to return a
2635 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
2637 emit_move_insn (struct_value_rtx,
2639 force_operand (structure_value_addr,
2642 /* Mark the memory for the aggregate as write-only. */
2643 if (current_function_check_memory_usage)
2644 emit_library_call (chkr_set_right_libfunc, 1,
2646 structure_value_addr, ptr_mode,
2647 GEN_INT (struct_value_size),
2648 TYPE_MODE (sizetype),
2649 GEN_INT (MEMORY_USE_WO),
2650 TYPE_MODE (integer_type_node));
2652 if (GET_CODE (struct_value_rtx) == REG)
2653 use_reg (&call_fusage, struct_value_rtx);
2656 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
2659 load_register_parameters (args, num_actuals, &call_fusage);
2661 /* Perform postincrements before actually calling the function. */
2664 /* Save a pointer to the last insn before the call, so that we can
2665 later safely search backwards to find the CALL_INSN. */
2666 before_call = get_last_insn ();
2668 /* All arguments and registers used for the call must be set up by
2671 /* Generate the actual call instruction. */
2672 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
2673 args_size.constant, struct_value_size,
2674 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2675 valreg, old_inhibit_defer_pop, call_fusage,
2676 ((is_const ? ECF_IS_CONST : 0)
2677 | (nothrow ? ECF_NOTHROW : 0)
2678 | (pass == 0 ? ECF_SIBCALL : 0)));
2680 /* If call is cse'able, make appropriate pair of reg-notes around it.
2681 Test valreg so we don't crash; may safely ignore `const'
2682 if return type is void. Disable for PARALLEL return values, because
2683 we have no way to move such values into a pseudo register. */
2684 if (is_const && valreg != 0 && GET_CODE (valreg) != PARALLEL)
2687 rtx temp = gen_reg_rtx (GET_MODE (valreg));
2690 /* Mark the return value as a pointer if needed. */
2691 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
2693 tree pointed_to = TREE_TYPE (TREE_TYPE (exp));
2694 mark_reg_pointer (temp, TYPE_ALIGN (pointed_to) / BITS_PER_UNIT);
2697 /* Construct an "equal form" for the value which mentions all the
2698 arguments in order as well as the function name. */
2699 #ifdef PUSH_ARGS_REVERSED
2700 for (i = 0; i < num_actuals; i++)
2701 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
2703 for (i = num_actuals - 1; i >= 0; i--)
2704 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
2706 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
2708 insns = get_insns ();
2711 emit_libcall_block (insns, temp, valreg, note);
2717 /* Otherwise, just write out the sequence without a note. */
2718 rtx insns = get_insns ();
2725 rtx temp = gen_reg_rtx (GET_MODE (valreg));
2728 /* The return value from a malloc-like function is a pointer. */
2729 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
2730 mark_reg_pointer (temp, BIGGEST_ALIGNMENT / BITS_PER_UNIT);
2732 emit_move_insn (temp, valreg);
2734 /* The return value from a malloc-like function can not alias
2736 last = get_last_insn ();
2738 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
2740 /* Write out the sequence. */
2741 insns = get_insns ();
2747 /* For calls to `setjmp', etc., inform flow.c it should complain
2748 if nonvolatile values are live. For functions that cannot return,
2749 inform flow that control does not fall through. */
2751 if (returns_twice || is_volatile || is_longjmp || pass == 0)
2753 /* The barrier or NOTE_INSN_SETJMP note must be emitted
2754 immediately after the CALL_INSN. Some ports emit more
2755 than just a CALL_INSN above, so we must search for it here. */
2757 rtx last = get_last_insn ();
2758 while (GET_CODE (last) != CALL_INSN)
2760 last = PREV_INSN (last);
2761 /* There was no CALL_INSN? */
2762 if (last == before_call)
2768 emit_note_after (NOTE_INSN_SETJMP, last);
2769 current_function_calls_setjmp = 1;
2770 sibcall_failure = 1;
2773 emit_barrier_after (last);
2777 current_function_calls_longjmp = 1, sibcall_failure = 1;
2779 /* If value type not void, return an rtx for the value. */
2781 /* If there are cleanups to be called, don't use a hard reg as target.
2782 We need to double check this and see if it matters anymore. */
2783 if (any_pending_cleanups (1)
2784 && target && REG_P (target)
2785 && REGNO (target) < FIRST_PSEUDO_REGISTER)
2786 target = 0, sibcall_failure = 1;
2788 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
2791 target = const0_rtx;
2793 else if (structure_value_addr)
2795 if (target == 0 || GET_CODE (target) != MEM)
2797 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
2798 memory_address (TYPE_MODE (TREE_TYPE (exp)),
2799 structure_value_addr));
2800 MEM_SET_IN_STRUCT_P (target,
2801 AGGREGATE_TYPE_P (TREE_TYPE (exp)));
2804 else if (pcc_struct_value)
2806 /* This is the special C++ case where we need to
2807 know what the true target was. We take care to
2808 never use this value more than once in one expression. */
2809 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
2810 copy_to_reg (valreg));
2811 MEM_SET_IN_STRUCT_P (target, AGGREGATE_TYPE_P (TREE_TYPE (exp)));
2813 /* Handle calls that return values in multiple non-contiguous locations.
2814 The Irix 6 ABI has examples of this. */
2815 else if (GET_CODE (valreg) == PARALLEL)
2817 int bytes = int_size_in_bytes (TREE_TYPE (exp));
2821 target = assign_stack_temp (TYPE_MODE (TREE_TYPE (exp)),
2823 MEM_SET_IN_STRUCT_P (target, AGGREGATE_TYPE_P (TREE_TYPE (exp)));
2824 preserve_temp_slots (target);
2827 if (! rtx_equal_p (target, valreg))
2828 emit_group_store (target, valreg, bytes,
2829 TYPE_ALIGN (TREE_TYPE (exp)) / BITS_PER_UNIT);
2830 /* We can not support sibling calls for this case. */
2831 sibcall_failure = 1;
2834 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
2835 && GET_MODE (target) == GET_MODE (valreg))
2837 /* TARGET and VALREG cannot be equal at this point because the
2838 latter would not have REG_FUNCTION_VALUE_P true, while the
2839 former would if it were referring to the same register.
2841 If they refer to the same register, this move will be a no-op,
2842 except when function inlining is being done. */
2843 emit_move_insn (target, valreg);
2845 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
2846 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
2848 target = copy_to_reg (valreg);
2850 #ifdef PROMOTE_FUNCTION_RETURN
2851 /* If we promoted this return value, make the proper SUBREG. TARGET
2852 might be const0_rtx here, so be careful. */
2853 if (GET_CODE (target) == REG
2854 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
2855 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
2857 tree type = TREE_TYPE (exp);
2858 int unsignedp = TREE_UNSIGNED (type);
2860 /* If we don't promote as expected, something is wrong. */
2861 if (GET_MODE (target)
2862 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
2865 target = gen_rtx_SUBREG (TYPE_MODE (type), target, 0);
2866 SUBREG_PROMOTED_VAR_P (target) = 1;
2867 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
2871 /* If size of args is variable or this was a constructor call for a stack
2872 argument, restore saved stack-pointer value. */
2874 if (old_stack_level)
2876 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
2877 pending_stack_adjust = old_pending_adj;
2878 #ifdef ACCUMULATE_OUTGOING_ARGS
2879 stack_arg_under_construction = old_stack_arg_under_construction;
2880 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2881 stack_usage_map = initial_stack_usage_map;
2883 sibcall_failure = 1;
2885 #ifdef ACCUMULATE_OUTGOING_ARGS
2888 #ifdef REG_PARM_STACK_SPACE
2891 restore_fixed_argument_area (save_area, argblock,
2892 high_to_save, low_to_save);
2893 sibcall_failure = 1;
2897 /* If we saved any argument areas, restore them. */
2898 for (i = 0; i < num_actuals; i++)
2899 if (args[i].save_area)
2901 enum machine_mode save_mode = GET_MODE (args[i].save_area);
2903 = gen_rtx_MEM (save_mode,
2904 memory_address (save_mode,
2905 XEXP (args[i].stack_slot, 0)));
2907 if (save_mode != BLKmode)
2908 emit_move_insn (stack_area, args[i].save_area);
2910 emit_block_move (stack_area,
2911 validize_mem (args[i].save_area),
2912 GEN_INT (args[i].size.constant),
2913 PARM_BOUNDARY / BITS_PER_UNIT);
2914 sibcall_failure = 1;
2917 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2918 stack_usage_map = initial_stack_usage_map;
2922 /* If this was alloca, record the new stack level for nonlocal gotos.
2923 Check for the handler slots since we might not have a save area
2924 for non-local gotos. */
2926 if (may_be_alloca && nonlocal_goto_handler_slots != 0)
2927 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
2931 /* Free up storage we no longer need. */
2932 for (i = 0; i < num_actuals; ++i)
2933 if (args[i].aligned_regs)
2934 free (args[i].aligned_regs);
2938 /* Undo the fake expand_start_target_temps we did earlier. If
2939 there had been any cleanups created, we've already set
2941 expand_end_target_temps ();
2944 insns = get_insns ();
2949 tail_call_insns = insns;
2951 /* If the current function's argument block is not large enough
2952 to hold the outoing arguments, or we encountered some other
2953 situation we couldn't handle, zero out the sequence. */
2954 if (current_function_args_size < args_size.constant
2956 tail_call_insns = NULL_RTX;
2958 /* Restore the pending stack adjustment now that we have
2959 finished generating the sibling call sequence. */
2960 pending_stack_adjust = save_pending_stack_adjust;
2963 normal_call_insns = insns;
2966 /* The function optimize_sibling_and_tail_recursive_calls doesn't
2967 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
2968 can happen if the arguments to this function call an inline
2969 function who's expansion contains another CALL_PLACEHOLDER.
2971 If there are any C_Ps in any of these sequences, replace them
2972 with their normal call. */
2974 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
2975 if (GET_CODE (insn) == CALL_INSN
2976 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
2977 replace_call_placeholder (insn, sibcall_use_normal);
2979 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
2980 if (GET_CODE (insn) == CALL_INSN
2981 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
2982 replace_call_placeholder (insn, sibcall_use_normal);
2984 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
2985 if (GET_CODE (insn) == CALL_INSN
2986 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
2987 replace_call_placeholder (insn, sibcall_use_normal);
2989 /* If this was a potential tail recursion site, then emit a
2990 CALL_PLACEHOLDER with the normal and the tail recursion streams.
2991 One of them will be selected later. */
2992 if (tail_recursion_insns || tail_call_insns)
2994 /* The tail recursion label must be kept around. We could expose
2995 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
2996 and makes determining true tail recursion sites difficult.
2998 So we set LABEL_PRESERVE_P here, then clear it when we select
2999 one of the call sequences after rtl generation is complete. */
3000 if (tail_recursion_insns)
3001 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3002 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3004 tail_recursion_insns,
3005 tail_recursion_label));
3008 emit_insns (normal_call_insns);
3010 currently_expanding_call--;
3015 /* Returns nonzero if FUN is the symbol for a library function which can
3019 libfunc_nothrow (fun)
3022 if (fun == throw_libfunc
3023 || fun == rethrow_libfunc
3024 || fun == sjthrow_libfunc
3025 || fun == sjpopnthrow_libfunc)
3031 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3032 The RETVAL parameter specifies whether return value needs to be saved, other
3033 parameters are documented in the emit_library_call function bellow. */
3035 emit_library_call_value_1 (retval, orgfun, value, no_queue, outmode, nargs, p)
3040 enum machine_mode outmode;
3044 /* Total size in bytes of all the stack-parms scanned so far. */
3045 struct args_size args_size;
3046 /* Size of arguments before any adjustments (such as rounding). */
3047 struct args_size original_args_size;
3048 register int argnum;
3052 struct args_size alignment_pad;
3054 CUMULATIVE_ARGS args_so_far;
3055 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
3056 struct args_size offset; struct args_size size; rtx save_area; };
3058 int old_inhibit_defer_pop = inhibit_defer_pop;
3059 rtx call_fusage = 0;
3061 int pcc_struct_value = 0;
3062 int struct_value_size = 0;
3064 int reg_parm_stack_space = 0;
3066 #ifdef ACCUMULATE_OUTGOING_ARGS
3070 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
3071 /* Define the boundary of the register parm stack space that needs to be
3073 int low_to_save = -1, high_to_save = 0;
3074 rtx save_area = 0; /* Place that it is saved */
3077 #ifdef ACCUMULATE_OUTGOING_ARGS
3078 /* Size of the stack reserved for parameter registers. */
3079 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3080 char *initial_stack_usage_map = stack_usage_map;
3083 #ifdef REG_PARM_STACK_SPACE
3084 #ifdef MAYBE_REG_PARM_STACK_SPACE
3085 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3087 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3091 is_const = no_queue;
3094 nothrow = libfunc_nothrow (fun);
3096 #ifdef PREFERRED_STACK_BOUNDARY
3097 /* Ensure current function's preferred stack boundary is at least
3099 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3100 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3103 /* If this kind of value comes back in memory,
3104 decide where in memory it should come back. */
3105 if (outmode != VOIDmode && aggregate_value_p (type_for_mode (outmode, 0)))
3107 #ifdef PCC_STATIC_STRUCT_RETURN
3109 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
3111 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3112 pcc_struct_value = 1;
3114 value = gen_reg_rtx (outmode);
3115 #else /* not PCC_STATIC_STRUCT_RETURN */
3116 struct_value_size = GET_MODE_SIZE (outmode);
3117 if (value != 0 && GET_CODE (value) == MEM)
3120 mem_value = assign_stack_temp (outmode, GET_MODE_SIZE (outmode), 0);
3123 /* This call returns a big structure. */
3127 /* ??? Unfinished: must pass the memory address as an argument. */
3129 /* Copy all the libcall-arguments out of the varargs data
3130 and into a vector ARGVEC.
3132 Compute how to pass each argument. We only support a very small subset
3133 of the full argument passing conventions to limit complexity here since
3134 library functions shouldn't have many args. */
3136 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3137 bzero ((char *) argvec, (nargs + 1) * sizeof (struct arg));
3139 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3141 args_size.constant = 0;
3148 /* If there's a structure value address to be passed,
3149 either pass it in the special place, or pass it as an extra argument. */
3150 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3152 rtx addr = XEXP (mem_value, 0);
3155 /* Make sure it is a reasonable operand for a move or push insn. */
3156 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3157 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3158 addr = force_operand (addr, NULL_RTX);
3160 argvec[count].value = addr;
3161 argvec[count].mode = Pmode;
3162 argvec[count].partial = 0;
3164 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3165 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3166 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3170 locate_and_pad_parm (Pmode, NULL_TREE,
3171 argvec[count].reg && argvec[count].partial == 0,
3172 NULL_TREE, &args_size, &argvec[count].offset,
3173 &argvec[count].size, &alignment_pad);
3176 if (argvec[count].reg == 0 || argvec[count].partial != 0
3177 || reg_parm_stack_space > 0)
3178 args_size.constant += argvec[count].size.constant;
3180 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3185 for (; count < nargs; count++)
3187 rtx val = va_arg (p, rtx);
3188 enum machine_mode mode = va_arg (p, enum machine_mode);
3190 /* We cannot convert the arg value to the mode the library wants here;
3191 must do it earlier where we know the signedness of the arg. */
3193 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3196 /* On some machines, there's no way to pass a float to a library fcn.
3197 Pass it as a double instead. */
3198 #ifdef LIBGCC_NEEDS_DOUBLE
3199 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3200 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3203 /* There's no need to call protect_from_queue, because
3204 either emit_move_insn or emit_push_insn will do that. */
3206 /* Make sure it is a reasonable operand for a move or push insn. */
3207 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3208 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3209 val = force_operand (val, NULL_RTX);
3211 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3212 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3214 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
3215 be viewed as just an efficiency improvement. */
3216 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
3217 emit_move_insn (slot, val);
3218 val = force_operand (XEXP (slot, 0), NULL_RTX);
3223 argvec[count].value = val;
3224 argvec[count].mode = mode;
3226 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3228 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3229 argvec[count].partial
3230 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3232 argvec[count].partial = 0;
3235 locate_and_pad_parm (mode, NULL_TREE,
3236 argvec[count].reg && argvec[count].partial == 0,
3237 NULL_TREE, &args_size, &argvec[count].offset,
3238 &argvec[count].size, &alignment_pad);
3240 if (argvec[count].size.var)
3243 if (reg_parm_stack_space == 0 && argvec[count].partial)
3244 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
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, mode, (tree) 0, 1);
3253 #ifdef FINAL_REG_PARM_STACK_SPACE
3254 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3257 /* If this machine requires an external definition for library
3258 functions, write one out. */
3259 assemble_external_libcall (fun);
3261 original_args_size = args_size;
3262 #ifdef PREFERRED_STACK_BOUNDARY
3263 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
3264 / STACK_BYTES) * STACK_BYTES);
3267 args_size.constant = MAX (args_size.constant,
3268 reg_parm_stack_space);
3270 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3271 args_size.constant -= reg_parm_stack_space;
3274 if (args_size.constant > current_function_outgoing_args_size)
3275 current_function_outgoing_args_size = args_size.constant;
3277 #ifdef ACCUMULATE_OUTGOING_ARGS
3278 /* Since the stack pointer will never be pushed, it is possible for
3279 the evaluation of a parm to clobber something we have already
3280 written to the stack. Since most function calls on RISC machines
3281 do not use the stack, this is uncommon, but must work correctly.
3283 Therefore, we save any area of the stack that was already written
3284 and that we are using. Here we set up to do this by making a new
3285 stack usage map from the old one.
3287 Another approach might be to try to reorder the argument
3288 evaluations to avoid this conflicting stack usage. */
3290 needed = args_size.constant;
3292 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3293 /* Since we will be writing into the entire argument area, the
3294 map must be allocated for its entire size, not just the part that
3295 is the responsibility of the caller. */
3296 needed += reg_parm_stack_space;
3299 #ifdef ARGS_GROW_DOWNWARD
3300 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3303 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3306 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3308 if (initial_highest_arg_in_use)
3309 bcopy (initial_stack_usage_map, stack_usage_map,
3310 initial_highest_arg_in_use);
3312 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3313 bzero (&stack_usage_map[initial_highest_arg_in_use],
3314 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3317 /* The address of the outgoing argument list must not be copied to a
3318 register here, because argblock would be left pointing to the
3319 wrong place after the call to allocate_dynamic_stack_space below.
3322 argblock = virtual_outgoing_args_rtx;
3323 #else /* not ACCUMULATE_OUTGOING_ARGS */
3324 #ifndef PUSH_ROUNDING
3325 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3329 #ifdef PUSH_ARGS_REVERSED
3330 #ifdef PREFERRED_STACK_BOUNDARY
3331 /* If we push args individually in reverse order, perform stack alignment
3332 before the first push (the last arg). */
3334 anti_adjust_stack (GEN_INT (args_size.constant
3335 - original_args_size.constant));
3339 #ifdef PUSH_ARGS_REVERSED
3347 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
3348 /* The argument list is the property of the called routine and it
3349 may clobber it. If the fixed area has been used for previous
3350 parameters, we must save and restore it.
3352 Here we compute the boundary of the that needs to be saved, if any. */
3354 #ifdef ARGS_GROW_DOWNWARD
3355 for (count = 0; count < reg_parm_stack_space + 1; count++)
3357 for (count = 0; count < reg_parm_stack_space; count++)
3360 if (count >= highest_outgoing_arg_in_use
3361 || stack_usage_map[count] == 0)
3364 if (low_to_save == -1)
3365 low_to_save = count;
3367 high_to_save = count;
3370 if (low_to_save >= 0)
3372 int num_to_save = high_to_save - low_to_save + 1;
3373 enum machine_mode save_mode
3374 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3377 /* If we don't have the required alignment, must do this in BLKmode. */
3378 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3379 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3380 save_mode = BLKmode;
3382 #ifdef ARGS_GROW_DOWNWARD
3383 stack_area = gen_rtx_MEM (save_mode,
3384 memory_address (save_mode,
3385 plus_constant (argblock,
3388 stack_area = gen_rtx_MEM (save_mode,
3389 memory_address (save_mode,
3390 plus_constant (argblock,
3393 if (save_mode == BLKmode)
3395 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3396 emit_block_move (validize_mem (save_area), stack_area,
3397 GEN_INT (num_to_save),
3398 PARM_BOUNDARY / BITS_PER_UNIT);
3402 save_area = gen_reg_rtx (save_mode);
3403 emit_move_insn (save_area, stack_area);
3408 /* Push the args that need to be pushed. */
3410 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3411 are to be pushed. */
3412 for (count = 0; count < nargs; count++, argnum += inc)
3414 register enum machine_mode mode = argvec[argnum].mode;
3415 register rtx val = argvec[argnum].value;
3416 rtx reg = argvec[argnum].reg;
3417 int partial = argvec[argnum].partial;
3418 #ifdef ACCUMULATE_OUTGOING_ARGS
3419 int lower_bound, upper_bound, i;
3422 if (! (reg != 0 && partial == 0))
3424 #ifdef ACCUMULATE_OUTGOING_ARGS
3425 /* If this is being stored into a pre-allocated, fixed-size, stack
3426 area, save any previous data at that location. */
3428 #ifdef ARGS_GROW_DOWNWARD
3429 /* stack_slot is negative, but we want to index stack_usage_map
3430 with positive values. */
3431 upper_bound = -argvec[argnum].offset.constant + 1;
3432 lower_bound = upper_bound - argvec[argnum].size.constant;
3434 lower_bound = argvec[argnum].offset.constant;
3435 upper_bound = lower_bound + argvec[argnum].size.constant;
3438 for (i = lower_bound; i < upper_bound; i++)
3439 if (stack_usage_map[i]
3440 /* Don't store things in the fixed argument area at this point;
3441 it has already been saved. */
3442 && i > reg_parm_stack_space)
3445 if (i != upper_bound)
3447 /* We need to make a save area. See what mode we can make it. */
3448 enum machine_mode save_mode
3449 = mode_for_size (argvec[argnum].size.constant * BITS_PER_UNIT,
3456 plus_constant (argblock,
3457 argvec[argnum].offset.constant)));
3458 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3460 emit_move_insn (argvec[argnum].save_area, stack_area);
3463 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
3464 argblock, GEN_INT (argvec[argnum].offset.constant),
3465 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3467 #ifdef ACCUMULATE_OUTGOING_ARGS
3468 /* Now mark the segment we just used. */
3469 for (i = lower_bound; i < upper_bound; i++)
3470 stack_usage_map[i] = 1;
3477 #ifndef PUSH_ARGS_REVERSED
3478 #ifdef PREFERRED_STACK_BOUNDARY
3479 /* If we pushed args in forward order, perform stack alignment
3480 after pushing the last arg. */
3482 anti_adjust_stack (GEN_INT (args_size.constant
3483 - original_args_size.constant));
3487 #ifdef PUSH_ARGS_REVERSED
3493 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
3495 /* Now load any reg parms into their regs. */
3497 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3498 are to be pushed. */
3499 for (count = 0; count < nargs; count++, argnum += inc)
3501 register rtx val = argvec[argnum].value;
3502 rtx reg = argvec[argnum].reg;
3503 int partial = argvec[argnum].partial;
3505 /* Handle calls that pass values in multiple non-contiguous
3506 locations. The PA64 has examples of this for library calls. */
3507 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3508 emit_group_load (reg, val,
3509 GET_MODE_SIZE (GET_MODE (val)),
3510 GET_MODE_ALIGNMENT (GET_MODE (val)));
3511 else if (reg != 0 && partial == 0)
3512 emit_move_insn (reg, val);
3518 /* For version 1.37, try deleting this entirely. */
3523 /* Any regs containing parms remain in use through the call. */
3524 for (count = 0; count < nargs; count++)
3526 rtx reg = argvec[count].reg;
3527 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3528 use_group_regs (&call_fusage, reg);
3530 use_reg (&call_fusage, reg);
3533 /* Pass the function the address in which to return a structure value. */
3534 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
3536 emit_move_insn (struct_value_rtx,
3538 force_operand (XEXP (mem_value, 0),
3540 if (GET_CODE (struct_value_rtx) == REG)
3541 use_reg (&call_fusage, struct_value_rtx);
3544 /* Don't allow popping to be deferred, since then
3545 cse'ing of library calls could delete a call and leave the pop. */
3548 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3549 will set inhibit_defer_pop to that value. */
3550 /* The return type is needed to decide how many bytes the function pops.
3551 Signedness plays no role in that, so for simplicity, we pretend it's
3552 always signed. We also assume that the list of arguments passed has
3553 no impact, so we pretend it is unknown. */
3556 get_identifier (XSTR (orgfun, 0)),
3557 build_function_type (outmode == VOIDmode ? void_type_node
3558 : type_for_mode (outmode, 0), NULL_TREE),
3559 original_args_size.constant, args_size.constant,
3561 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
3562 mem_value == 0 && outmode != VOIDmode ? hard_libcall_value (outmode) : NULL_RTX,
3563 old_inhibit_defer_pop + 1, call_fusage,
3564 ((is_const ? ECF_IS_CONST : 0)
3565 | (nothrow ? ECF_NOTHROW : 0)));
3567 /* Now restore inhibit_defer_pop to its actual original value. */
3572 /* Copy the value to the right place. */
3573 if (outmode != VOIDmode && retval)
3579 if (value != mem_value)
3580 emit_move_insn (value, mem_value);
3582 else if (value != 0)
3583 emit_move_insn (value, hard_libcall_value (outmode));
3585 value = hard_libcall_value (outmode);
3588 #ifdef ACCUMULATE_OUTGOING_ARGS
3589 #ifdef REG_PARM_STACK_SPACE
3592 enum machine_mode save_mode = GET_MODE (save_area);
3593 #ifdef ARGS_GROW_DOWNWARD
3595 = gen_rtx_MEM (save_mode,
3596 memory_address (save_mode,
3597 plus_constant (argblock,
3601 = gen_rtx_MEM (save_mode,
3602 memory_address (save_mode,
3603 plus_constant (argblock, low_to_save)));
3605 if (save_mode != BLKmode)
3606 emit_move_insn (stack_area, save_area);
3608 emit_block_move (stack_area, validize_mem (save_area),
3609 GEN_INT (high_to_save - low_to_save + 1),
3610 PARM_BOUNDARY / BITS_PER_UNIT);
3614 /* If we saved any argument areas, restore them. */
3615 for (count = 0; count < nargs; count++)
3616 if (argvec[count].save_area)
3618 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
3620 = gen_rtx_MEM (save_mode,
3623 plus_constant (argblock,
3624 argvec[count].offset.constant)));
3626 emit_move_insn (stack_area, argvec[count].save_area);
3629 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3630 stack_usage_map = initial_stack_usage_map;
3637 /* Output a library call to function FUN (a SYMBOL_REF rtx)
3638 (emitting the queue unless NO_QUEUE is nonzero),
3639 for a value of mode OUTMODE,
3640 with NARGS different arguments, passed as alternating rtx values
3641 and machine_modes to convert them to.
3642 The rtx values should have been passed through protect_from_queue already.
3644 NO_QUEUE will be true if and only if the library call is a `const' call
3645 which will be enclosed in REG_LIBCALL/REG_RETVAL notes; it is equivalent
3646 to the variable is_const in expand_call.
3648 NO_QUEUE must be true for const calls, because if it isn't, then
3649 any pending increment will be emitted between REG_LIBCALL/REG_RETVAL notes,
3650 and will be lost if the libcall sequence is optimized away.
3652 NO_QUEUE must be false for non-const calls, because if it isn't, the
3653 call insn will have its CONST_CALL_P bit set, and it will be incorrectly
3654 optimized. For instance, the instruction scheduler may incorrectly
3655 move memory references across the non-const call. */
3658 emit_library_call VPARAMS((rtx orgfun, int no_queue, enum machine_mode outmode,
3661 #ifndef ANSI_PROTOTYPES
3664 enum machine_mode outmode;
3669 VA_START (p, nargs);
3671 #ifndef ANSI_PROTOTYPES
3672 orgfun = va_arg (p, rtx);
3673 no_queue = va_arg (p, int);
3674 outmode = va_arg (p, enum machine_mode);
3675 nargs = va_arg (p, int);
3678 emit_library_call_value_1 (0, orgfun, NULL_RTX, no_queue, outmode, nargs, p);
3683 /* Like emit_library_call except that an extra argument, VALUE,
3684 comes second and says where to store the result.
3685 (If VALUE is zero, this function chooses a convenient way
3686 to return the value.
3688 This function returns an rtx for where the value is to be found.
3689 If VALUE is nonzero, VALUE is returned. */
3692 emit_library_call_value VPARAMS((rtx orgfun, rtx value, int no_queue,
3693 enum machine_mode outmode, int nargs, ...))
3695 #ifndef ANSI_PROTOTYPES
3699 enum machine_mode outmode;
3704 VA_START (p, nargs);
3706 #ifndef ANSI_PROTOTYPES
3707 orgfun = va_arg (p, rtx);
3708 value = va_arg (p, rtx);
3709 no_queue = va_arg (p, int);
3710 outmode = va_arg (p, enum machine_mode);
3711 nargs = va_arg (p, int);
3714 value = emit_library_call_value_1 (1, orgfun, value, no_queue, outmode, nargs, p);
3722 /* Return an rtx which represents a suitable home on the stack
3723 given TYPE, the type of the argument looking for a home.
3724 This is called only for BLKmode arguments.
3726 SIZE is the size needed for this target.
3727 ARGS_ADDR is the address of the bottom of the argument block for this call.
3728 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
3729 if this machine uses push insns. */
3732 target_for_arg (type, size, args_addr, offset)
3736 struct args_size offset;
3739 rtx offset_rtx = ARGS_SIZE_RTX (offset);
3741 /* We do not call memory_address if possible,
3742 because we want to address as close to the stack
3743 as possible. For non-variable sized arguments,
3744 this will be stack-pointer relative addressing. */
3745 if (GET_CODE (offset_rtx) == CONST_INT)
3746 target = plus_constant (args_addr, INTVAL (offset_rtx));
3749 /* I have no idea how to guarantee that this
3750 will work in the presence of register parameters. */
3751 target = gen_rtx_PLUS (Pmode, args_addr, offset_rtx);
3752 target = memory_address (QImode, target);
3755 return gen_rtx_MEM (BLKmode, target);
3759 /* Store a single argument for a function call
3760 into the register or memory area where it must be passed.
3761 *ARG describes the argument value and where to pass it.
3763 ARGBLOCK is the address of the stack-block for all the arguments,
3764 or 0 on a machine where arguments are pushed individually.
3766 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
3767 so must be careful about how the stack is used.
3769 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
3770 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
3771 that we need not worry about saving and restoring the stack.
3773 FNDECL is the declaration of the function we are calling. */
3776 store_one_arg (arg, argblock, may_be_alloca, variable_size,
3777 reg_parm_stack_space)
3778 struct arg_data *arg;
3781 int variable_size ATTRIBUTE_UNUSED;
3782 int reg_parm_stack_space;
3784 register tree pval = arg->tree_value;
3788 #ifdef ACCUMULATE_OUTGOING_ARGS
3789 int i, lower_bound = 0, upper_bound = 0;
3792 if (TREE_CODE (pval) == ERROR_MARK)
3795 /* Push a new temporary level for any temporaries we make for
3799 #ifdef ACCUMULATE_OUTGOING_ARGS
3800 /* If this is being stored into a pre-allocated, fixed-size, stack area,
3801 save any previous data at that location. */
3802 if (argblock && ! variable_size && arg->stack)
3804 #ifdef ARGS_GROW_DOWNWARD
3805 /* stack_slot is negative, but we want to index stack_usage_map
3806 with positive values. */
3807 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
3808 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
3812 lower_bound = upper_bound - arg->size.constant;
3814 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
3815 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
3819 upper_bound = lower_bound + arg->size.constant;
3822 for (i = lower_bound; i < upper_bound; i++)
3823 if (stack_usage_map[i]
3824 /* Don't store things in the fixed argument area at this point;
3825 it has already been saved. */
3826 && i > reg_parm_stack_space)
3829 if (i != upper_bound)
3831 /* We need to make a save area. See what mode we can make it. */
3832 enum machine_mode save_mode
3833 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
3835 = gen_rtx_MEM (save_mode,
3836 memory_address (save_mode,
3837 XEXP (arg->stack_slot, 0)));
3839 if (save_mode == BLKmode)
3841 arg->save_area = assign_stack_temp (BLKmode,
3842 arg->size.constant, 0);
3843 MEM_SET_IN_STRUCT_P (arg->save_area,
3844 AGGREGATE_TYPE_P (TREE_TYPE
3845 (arg->tree_value)));
3846 preserve_temp_slots (arg->save_area);
3847 emit_block_move (validize_mem (arg->save_area), stack_area,
3848 GEN_INT (arg->size.constant),
3849 PARM_BOUNDARY / BITS_PER_UNIT);
3853 arg->save_area = gen_reg_rtx (save_mode);
3854 emit_move_insn (arg->save_area, stack_area);
3859 /* Now that we have saved any slots that will be overwritten by this
3860 store, mark all slots this store will use. We must do this before
3861 we actually expand the argument since the expansion itself may
3862 trigger library calls which might need to use the same stack slot. */
3863 if (argblock && ! variable_size && arg->stack)
3864 for (i = lower_bound; i < upper_bound; i++)
3865 stack_usage_map[i] = 1;
3868 /* If this isn't going to be placed on both the stack and in registers,
3869 set up the register and number of words. */
3870 if (! arg->pass_on_stack)
3871 reg = arg->reg, partial = arg->partial;
3873 if (reg != 0 && partial == 0)
3874 /* Being passed entirely in a register. We shouldn't be called in
3878 /* If this arg needs special alignment, don't load the registers
3880 if (arg->n_aligned_regs != 0)
3883 /* If this is being passed partially in a register, we can't evaluate
3884 it directly into its stack slot. Otherwise, we can. */
3885 if (arg->value == 0)
3887 #ifdef ACCUMULATE_OUTGOING_ARGS
3888 /* stack_arg_under_construction is nonzero if a function argument is
3889 being evaluated directly into the outgoing argument list and
3890 expand_call must take special action to preserve the argument list
3891 if it is called recursively.
3893 For scalar function arguments stack_usage_map is sufficient to
3894 determine which stack slots must be saved and restored. Scalar
3895 arguments in general have pass_on_stack == 0.
3897 If this argument is initialized by a function which takes the
3898 address of the argument (a C++ constructor or a C function
3899 returning a BLKmode structure), then stack_usage_map is
3900 insufficient and expand_call must push the stack around the
3901 function call. Such arguments have pass_on_stack == 1.
3903 Note that it is always safe to set stack_arg_under_construction,
3904 but this generates suboptimal code if set when not needed. */
3906 if (arg->pass_on_stack)
3907 stack_arg_under_construction++;
3909 arg->value = expand_expr (pval,
3911 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
3912 ? NULL_RTX : arg->stack,
3915 /* If we are promoting object (or for any other reason) the mode
3916 doesn't agree, convert the mode. */
3918 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
3919 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
3920 arg->value, arg->unsignedp);
3922 #ifdef ACCUMULATE_OUTGOING_ARGS
3923 if (arg->pass_on_stack)
3924 stack_arg_under_construction--;
3928 /* Don't allow anything left on stack from computation
3929 of argument to alloca. */
3931 do_pending_stack_adjust ();
3933 if (arg->value == arg->stack)
3935 /* If the value is already in the stack slot, we are done. */
3936 if (current_function_check_memory_usage && GET_CODE (arg->stack) == MEM)
3938 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
3939 XEXP (arg->stack, 0), Pmode,
3940 ARGS_SIZE_RTX (arg->size),
3941 TYPE_MODE (sizetype),
3942 GEN_INT (MEMORY_USE_RW),
3943 TYPE_MODE (integer_type_node));
3946 else if (arg->mode != BLKmode)
3950 /* Argument is a scalar, not entirely passed in registers.
3951 (If part is passed in registers, arg->partial says how much
3952 and emit_push_insn will take care of putting it there.)
3954 Push it, and if its size is less than the
3955 amount of space allocated to it,
3956 also bump stack pointer by the additional space.
3957 Note that in C the default argument promotions
3958 will prevent such mismatches. */
3960 size = GET_MODE_SIZE (arg->mode);
3961 /* Compute how much space the push instruction will push.
3962 On many machines, pushing a byte will advance the stack
3963 pointer by a halfword. */
3964 #ifdef PUSH_ROUNDING
3965 size = PUSH_ROUNDING (size);
3969 /* Compute how much space the argument should get:
3970 round up to a multiple of the alignment for arguments. */
3971 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
3972 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
3973 / (PARM_BOUNDARY / BITS_PER_UNIT))
3974 * (PARM_BOUNDARY / BITS_PER_UNIT));
3976 /* This isn't already where we want it on the stack, so put it there.
3977 This can either be done with push or copy insns. */
3978 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX, 0,
3979 partial, reg, used - size, argblock,
3980 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
3981 ARGS_SIZE_RTX (arg->alignment_pad));
3983 arg_space_so_far += used;
3987 /* BLKmode, at least partly to be pushed. */
3989 register int excess;
3992 /* Pushing a nonscalar.
3993 If part is passed in registers, PARTIAL says how much
3994 and emit_push_insn will take care of putting it there. */
3996 /* Round its size up to a multiple
3997 of the allocation unit for arguments. */
3999 if (arg->size.var != 0)
4002 size_rtx = ARGS_SIZE_RTX (arg->size);
4006 /* PUSH_ROUNDING has no effect on us, because
4007 emit_push_insn for BLKmode is careful to avoid it. */
4008 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4009 + partial * UNITS_PER_WORD);
4010 size_rtx = expr_size (pval);
4011 arg_space_so_far += excess + INTVAL (size_rtx);
4014 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4015 TYPE_ALIGN (TREE_TYPE (pval)) / BITS_PER_UNIT, partial,
4016 reg, excess, argblock, ARGS_SIZE_RTX (arg->offset),
4017 reg_parm_stack_space,
4018 ARGS_SIZE_RTX (arg->alignment_pad));
4022 /* Unless this is a partially-in-register argument, the argument is now
4025 ??? Note that this can change arg->value from arg->stack to
4026 arg->stack_slot and it matters when they are not the same.
4027 It isn't totally clear that this is correct in all cases. */
4029 arg->value = arg->stack_slot;
4031 /* Once we have pushed something, pops can't safely
4032 be deferred during the rest of the arguments. */
4035 /* ANSI doesn't require a sequence point here,
4036 but PCC has one, so this will avoid some problems. */
4039 /* Free any temporary slots made in processing this argument. Show
4040 that we might have taken the address of something and pushed that
4042 preserve_temp_slots (NULL_RTX);