1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 92-97, 1998, 1999 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
29 #include "insn-flags.h"
34 #if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY
35 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
38 /* Decide whether a function's arguments should be processed
39 from first to last or from last to first.
41 They should if the stack and args grow in opposite directions, but
42 only if we have push insns. */
46 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
47 #define PUSH_ARGS_REVERSED /* If it's last to first */
52 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
53 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
55 /* Data structure and subroutines used within expand_call. */
59 /* Tree node for this argument. */
61 /* Mode for value; TYPE_MODE unless promoted. */
62 enum machine_mode mode;
63 /* Current RTL value for argument, or 0 if it isn't precomputed. */
65 /* Initially-compute RTL value for argument; only for const functions. */
67 /* Register to pass this argument in, 0 if passed on stack, or an
68 PARALLEL if the arg is to be copied into multiple non-contiguous
71 /* If REG was promoted from the actual mode of the argument expression,
72 indicates whether the promotion is sign- or zero-extended. */
74 /* Number of registers to use. 0 means put the whole arg in registers.
75 Also 0 if not passed in registers. */
77 /* Non-zero if argument must be passed on stack.
78 Note that some arguments may be passed on the stack
79 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
80 pass_on_stack identifies arguments that *cannot* go in registers. */
82 /* Offset of this argument from beginning of stack-args. */
83 struct args_size offset;
84 /* Similar, but offset to the start of the stack slot. Different from
85 OFFSET if this arg pads downward. */
86 struct args_size slot_offset;
87 /* Size of this argument on the stack, rounded up for any padding it gets,
88 parts of the argument passed in registers do not count.
89 If REG_PARM_STACK_SPACE is defined, then register parms
90 are counted here as well. */
91 struct args_size size;
92 /* Location on the stack at which parameter should be stored. The store
93 has already been done if STACK == VALUE. */
95 /* Location on the stack of the start of this argument slot. This can
96 differ from STACK if this arg pads downward. This location is known
97 to be aligned to FUNCTION_ARG_BOUNDARY. */
99 #ifdef ACCUMULATE_OUTGOING_ARGS
100 /* Place that this stack area has been saved, if needed. */
103 /* If an argument's alignment does not permit direct copying into registers,
104 copy in smaller-sized pieces into pseudos. These are stored in a
105 block pointed to by this field. The next field says how many
106 word-sized pseudos we made. */
109 /* The amount that the stack pointer needs to be adjusted to
110 force alignment for the next argument. */
111 struct args_size alignment_pad;
114 #ifdef ACCUMULATE_OUTGOING_ARGS
115 /* A vector of one char per byte of stack space. A byte if non-zero if
116 the corresponding stack location has been used.
117 This vector is used to prevent a function call within an argument from
118 clobbering any stack already set up. */
119 static char *stack_usage_map;
121 /* Size of STACK_USAGE_MAP. */
122 static int highest_outgoing_arg_in_use;
124 /* stack_arg_under_construction is nonzero when an argument may be
125 initialized with a constructor call (including a C function that
126 returns a BLKmode struct) and expand_call must take special action
127 to make sure the object being constructed does not overlap the
128 argument list for the constructor call. */
129 int stack_arg_under_construction;
132 static int calls_function PROTO ((tree, int));
133 static int calls_function_1 PROTO ((tree, int));
134 static void emit_call_1 PROTO ((rtx, tree, tree, HOST_WIDE_INT,
135 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
136 rtx, int, rtx, int));
137 static void special_function_p PROTO ((char *, tree, int *, int *,
139 static void precompute_register_parameters PROTO ((int, struct arg_data *,
141 static void store_one_arg PROTO ((struct arg_data *, rtx, int, int,
143 static void store_unaligned_arguments_into_pseudos PROTO ((struct arg_data *,
145 static int finalize_must_preallocate PROTO ((int, int,
147 struct args_size *));
148 static void precompute_arguments PROTO ((int, int, int,
150 struct args_size *));
151 static int compute_argument_block_size PROTO ((int,
152 struct args_size *));
153 static void initialize_argument_information PROTO ((int,
160 static void compute_argument_addresses PROTO ((struct arg_data *,
162 static rtx rtx_for_function_call PROTO ((tree, tree));
163 static void load_register_parameters PROTO ((struct arg_data *,
166 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
167 static rtx save_fixed_argument_area PROTO ((int, rtx, int *, int *));
168 static void restore_fixed_argument_area PROTO ((rtx, rtx, int, int));
171 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
174 If WHICH is 0, return 1 if EXP contains a call to any function.
175 Actually, we only need return 1 if evaluating EXP would require pushing
176 arguments on the stack, but that is too difficult to compute, so we just
177 assume any function call might require the stack. */
179 static tree calls_function_save_exprs;
182 calls_function (exp, which)
187 calls_function_save_exprs = 0;
188 val = calls_function_1 (exp, which);
189 calls_function_save_exprs = 0;
194 calls_function_1 (exp, which)
199 enum tree_code code = TREE_CODE (exp);
200 int type = TREE_CODE_CLASS (code);
201 int length = tree_code_length[(int) code];
203 /* If this code is language-specific, we don't know what it will do. */
204 if ((int) code >= NUM_TREE_CODES)
207 /* Only expressions and references can contain calls. */
208 if (type != 'e' && type != '<' && type != '1' && type != '2' && type != 'r'
217 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
218 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
221 tree fndecl = TREE_OPERAND (TREE_OPERAND (exp, 0), 0);
223 if ((DECL_BUILT_IN (fndecl)
224 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
225 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_ALLOCA)
226 || (DECL_SAVED_INSNS (fndecl)
227 && DECL_SAVED_INSNS (fndecl)->calls_alloca))
231 /* Third operand is RTL. */
236 if (SAVE_EXPR_RTL (exp) != 0)
238 if (value_member (exp, calls_function_save_exprs))
240 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
241 calls_function_save_exprs);
242 return (TREE_OPERAND (exp, 0) != 0
243 && calls_function_1 (TREE_OPERAND (exp, 0), which));
249 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
250 if (DECL_INITIAL (local) != 0
251 && calls_function_1 (DECL_INITIAL (local), which))
255 register tree subblock;
257 for (subblock = BLOCK_SUBBLOCKS (exp);
259 subblock = TREE_CHAIN (subblock))
260 if (calls_function_1 (subblock, which))
265 case METHOD_CALL_EXPR:
269 case WITH_CLEANUP_EXPR:
280 for (i = 0; i < length; i++)
281 if (TREE_OPERAND (exp, i) != 0
282 && calls_function_1 (TREE_OPERAND (exp, i), which))
288 /* Force FUNEXP into a form suitable for the address of a CALL,
289 and return that as an rtx. Also load the static chain register
290 if FNDECL is a nested function.
292 CALL_FUSAGE points to a variable holding the prospective
293 CALL_INSN_FUNCTION_USAGE information. */
296 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen)
302 rtx static_chain_value = 0;
304 funexp = protect_from_queue (funexp, 0);
307 /* Get possible static chain value for nested function in C. */
308 static_chain_value = lookup_static_chain (fndecl);
310 /* Make a valid memory address and copy constants thru pseudo-regs,
311 but not for a constant address if -fno-function-cse. */
312 if (GET_CODE (funexp) != SYMBOL_REF)
313 /* If we are using registers for parameters, force the
314 function address into a register now. */
315 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
316 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
317 : memory_address (FUNCTION_MODE, funexp));
320 #ifndef NO_FUNCTION_CSE
321 if (optimize && ! flag_no_function_cse)
322 #ifdef NO_RECURSIVE_FUNCTION_CSE
323 if (fndecl != current_function_decl)
325 funexp = force_reg (Pmode, funexp);
329 if (static_chain_value != 0)
331 emit_move_insn (static_chain_rtx, static_chain_value);
333 if (GET_CODE (static_chain_rtx) == REG)
334 use_reg (call_fusage, static_chain_rtx);
340 /* Generate instructions to call function FUNEXP,
341 and optionally pop the results.
342 The CALL_INSN is the first insn generated.
344 FNDECL is the declaration node of the function. This is given to the
345 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
347 FUNTYPE is the data type of the function. This is given to the macro
348 RETURN_POPS_ARGS to determine whether this function pops its own args.
349 We used to allow an identifier for library functions, but that doesn't
350 work when the return type is an aggregate type and the calling convention
351 says that the pointer to this aggregate is to be popped by the callee.
353 STACK_SIZE is the number of bytes of arguments on the stack,
354 rounded up to PREFERRED_STACK_BOUNDARY; zero if the size is variable.
355 This is both to put into the call insn and
356 to generate explicit popping code if necessary.
358 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
359 It is zero if this call doesn't want a structure value.
361 NEXT_ARG_REG is the rtx that results from executing
362 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
363 just after all the args have had their registers assigned.
364 This could be whatever you like, but normally it is the first
365 arg-register beyond those used for args in this call,
366 or 0 if all the arg-registers are used in this call.
367 It is passed on to `gen_call' so you can put this info in the call insn.
369 VALREG is a hard register in which a value is returned,
370 or 0 if the call does not return a value.
372 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
373 the args to this call were processed.
374 We restore `inhibit_defer_pop' to that value.
376 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
377 denote registers used by the called function.
379 IS_CONST is true if this is a `const' call. */
382 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
383 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
384 call_fusage, is_const)
386 tree fndecl ATTRIBUTE_UNUSED;
387 tree funtype ATTRIBUTE_UNUSED;
388 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
389 HOST_WIDE_INT rounded_stack_size;
390 HOST_WIDE_INT struct_value_size;
393 int old_inhibit_defer_pop;
397 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
398 rtx struct_value_size_rtx = GEN_INT (struct_value_size);
400 #ifndef ACCUMULATE_OUTGOING_ARGS
401 int already_popped = 0;
402 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
405 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
406 and we don't want to load it into a register as an optimization,
407 because prepare_call_address already did it if it should be done. */
408 if (GET_CODE (funexp) != SYMBOL_REF)
409 funexp = memory_address (FUNCTION_MODE, funexp);
411 #ifndef ACCUMULATE_OUTGOING_ARGS
412 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
413 /* If the target has "call" or "call_value" insns, then prefer them
414 if no arguments are actually popped. If the target does not have
415 "call" or "call_value" insns, then we must use the popping versions
416 even if the call has no arguments to pop. */
417 #if defined (HAVE_call) && defined (HAVE_call_value)
418 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
421 if (HAVE_call_pop && HAVE_call_value_pop)
424 rtx n_pop = GEN_INT (n_popped);
427 /* If this subroutine pops its own args, record that in the call insn
428 if possible, for the sake of frame pointer elimination. */
431 pat = gen_call_value_pop (valreg,
432 gen_rtx_MEM (FUNCTION_MODE, funexp),
433 rounded_stack_size_rtx, next_arg_reg, n_pop);
435 pat = gen_call_pop (gen_rtx_MEM (FUNCTION_MODE, funexp),
436 rounded_stack_size_rtx, next_arg_reg, n_pop);
438 emit_call_insn (pat);
445 #if defined (HAVE_call) && defined (HAVE_call_value)
446 if (HAVE_call && HAVE_call_value)
449 emit_call_insn (gen_call_value (valreg,
450 gen_rtx_MEM (FUNCTION_MODE, funexp),
451 rounded_stack_size_rtx, next_arg_reg,
454 emit_call_insn (gen_call (gen_rtx_MEM (FUNCTION_MODE, funexp),
455 rounded_stack_size_rtx, next_arg_reg,
456 struct_value_size_rtx));
462 /* Find the CALL insn we just emitted. */
463 for (call_insn = get_last_insn ();
464 call_insn && GET_CODE (call_insn) != CALL_INSN;
465 call_insn = PREV_INSN (call_insn))
471 /* Put the register usage information on the CALL. If there is already
472 some usage information, put ours at the end. */
473 if (CALL_INSN_FUNCTION_USAGE (call_insn))
477 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
478 link = XEXP (link, 1))
481 XEXP (link, 1) = call_fusage;
484 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
486 /* If this is a const call, then set the insn's unchanging bit. */
488 CONST_CALL_P (call_insn) = 1;
490 /* Restore this now, so that we do defer pops for this call's args
491 if the context of the call as a whole permits. */
492 inhibit_defer_pop = old_inhibit_defer_pop;
494 #ifndef ACCUMULATE_OUTGOING_ARGS
495 /* If returning from the subroutine does not automatically pop the args,
496 we need an instruction to pop them sooner or later.
497 Perhaps do it now; perhaps just record how much space to pop later.
499 If returning from the subroutine does pop the args, indicate that the
500 stack pointer will be changed. */
505 CALL_INSN_FUNCTION_USAGE (call_insn)
506 = gen_rtx_EXPR_LIST (VOIDmode,
507 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
508 CALL_INSN_FUNCTION_USAGE (call_insn));
509 rounded_stack_size -= n_popped;
510 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
513 if (rounded_stack_size != 0)
515 if (flag_defer_pop && inhibit_defer_pop == 0 && !is_const)
516 pending_stack_adjust += rounded_stack_size;
518 adjust_stack (rounded_stack_size_rtx);
523 /* Determine if the function identified by NAME and FNDECL is one with
524 special properties we wish to know about.
526 For example, if the function might return more than one time (setjmp), then
527 set RETURNS_TWICE to a nonzero value.
529 Similarly set IS_LONGJMP for if the function is in the longjmp family.
531 Set IS_MALLOC for any of the standard memory allocation functions which
532 allocate from the heap.
534 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
535 space from the stack such as alloca. */
538 special_function_p (name, fndecl, returns_twice, is_longjmp,
539 is_malloc, may_be_alloca)
552 if (name != 0 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
553 /* Exclude functions not at the file scope, or not `extern',
554 since they are not the magic functions we would otherwise
556 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
560 /* We assume that alloca will always be called by name. It
561 makes no sense to pass it as a pointer-to-function to
562 anything that does not understand its behavior. */
564 = (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
566 && ! strcmp (name, "alloca"))
567 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
569 && ! strcmp (name, "__builtin_alloca"))));
571 /* Disregard prefix _, __ or __x. */
574 if (name[1] == '_' && name[2] == 'x')
576 else if (name[1] == '_')
586 && (! strcmp (tname, "setjmp")
587 || ! strcmp (tname, "setjmp_syscall")))
589 && ! strcmp (tname, "sigsetjmp"))
591 && ! strcmp (tname, "savectx")));
593 && ! strcmp (tname, "siglongjmp"))
596 else if ((tname[0] == 'q' && tname[1] == 's'
597 && ! strcmp (tname, "qsetjmp"))
598 || (tname[0] == 'v' && tname[1] == 'f'
599 && ! strcmp (tname, "vfork")))
602 else if (tname[0] == 'l' && tname[1] == 'o'
603 && ! strcmp (tname, "longjmp"))
605 /* XXX should have "malloc" attribute on functions instead
606 of recognizing them by name. */
607 else if (! strcmp (tname, "malloc")
608 || ! strcmp (tname, "calloc")
609 || ! strcmp (tname, "realloc")
610 /* Note use of NAME rather than TNAME here. These functions
611 are only reserved when preceded with __. */
612 || ! strcmp (name, "__vn") /* mangled __builtin_vec_new */
613 || ! strcmp (name, "__nw") /* mangled __builtin_new */
614 || ! strcmp (name, "__builtin_new")
615 || ! strcmp (name, "__builtin_vec_new"))
620 /* Precompute all register parameters as described by ARGS, storing values
621 into fields within the ARGS array.
623 NUM_ACTUALS indicates the total number elements in the ARGS array.
625 Set REG_PARM_SEEN if we encounter a register parameter. */
628 precompute_register_parameters (num_actuals, args, reg_parm_seen)
630 struct arg_data *args;
637 for (i = 0; i < num_actuals; i++)
638 if (args[i].reg != 0 && ! args[i].pass_on_stack)
642 if (args[i].value == 0)
645 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
647 preserve_temp_slots (args[i].value);
650 /* ANSI doesn't require a sequence point here,
651 but PCC has one, so this will avoid some problems. */
655 /* If we are to promote the function arg to a wider mode,
658 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
660 = convert_modes (args[i].mode,
661 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
662 args[i].value, args[i].unsignedp);
664 /* If the value is expensive, and we are inside an appropriately
665 short loop, put the value into a pseudo and then put the pseudo
668 For small register classes, also do this if this call uses
669 register parameters. This is to avoid reload conflicts while
670 loading the parameters registers. */
672 if ((! (GET_CODE (args[i].value) == REG
673 || (GET_CODE (args[i].value) == SUBREG
674 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
675 && args[i].mode != BLKmode
676 && rtx_cost (args[i].value, SET) > 2
677 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
678 || preserve_subexpressions_p ()))
679 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
683 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
685 /* The argument list is the property of the called routine and it
686 may clobber it. If the fixed area has been used for previous
687 parameters, we must save and restore it. */
689 save_fixed_argument_area (reg_parm_stack_space, argblock,
690 low_to_save, high_to_save)
691 int reg_parm_stack_space;
697 rtx save_area = NULL_RTX;
699 /* Compute the boundary of the that needs to be saved, if any. */
700 #ifdef ARGS_GROW_DOWNWARD
701 for (i = 0; i < reg_parm_stack_space + 1; i++)
703 for (i = 0; i < reg_parm_stack_space; i++)
706 if (i >= highest_outgoing_arg_in_use
707 || stack_usage_map[i] == 0)
710 if (*low_to_save == -1)
716 if (*low_to_save >= 0)
718 int num_to_save = *high_to_save - *low_to_save + 1;
719 enum machine_mode save_mode
720 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
723 /* If we don't have the required alignment, must do this in BLKmode. */
724 if ((*low_to_save & (MIN (GET_MODE_SIZE (save_mode),
725 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
728 #ifdef ARGS_GROW_DOWNWARD
729 stack_area = gen_rtx_MEM (save_mode,
730 memory_address (save_mode,
731 plus_constant (argblock,
734 stack_area = gen_rtx_MEM (save_mode,
735 memory_address (save_mode,
736 plus_constant (argblock,
739 if (save_mode == BLKmode)
741 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
742 emit_block_move (validize_mem (save_area), stack_area,
743 GEN_INT (num_to_save),
744 PARM_BOUNDARY / BITS_PER_UNIT);
748 save_area = gen_reg_rtx (save_mode);
749 emit_move_insn (save_area, stack_area);
756 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
762 enum machine_mode save_mode = GET_MODE (save_area);
763 #ifdef ARGS_GROW_DOWNWARD
765 = gen_rtx_MEM (save_mode,
766 memory_address (save_mode,
767 plus_constant (argblock,
771 = gen_rtx_MEM (save_mode,
772 memory_address (save_mode,
773 plus_constant (argblock,
777 if (save_mode != BLKmode)
778 emit_move_insn (stack_area, save_area);
780 emit_block_move (stack_area, validize_mem (save_area),
781 GEN_INT (high_to_save - low_to_save + 1),
782 PARM_BOUNDARY / BITS_PER_UNIT);
786 /* If any elements in ARGS refer to parameters that are to be passed in
787 registers, but not in memory, and whose alignment does not permit a
788 direct copy into registers. Copy the values into a group of pseudos
789 which we will later copy into the appropriate hard registers.
791 Pseudos for each unaligned argument will be stored into the array
792 args[argnum].aligned_regs. The caller is responsible for deallocating
793 the aligned_regs array if it is nonzero. */
796 store_unaligned_arguments_into_pseudos (args, num_actuals)
797 struct arg_data *args;
802 for (i = 0; i < num_actuals; i++)
803 if (args[i].reg != 0 && ! args[i].pass_on_stack
804 && args[i].mode == BLKmode
805 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
806 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
808 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
809 int big_endian_correction = 0;
811 args[i].n_aligned_regs
812 = args[i].partial ? args[i].partial
813 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
815 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
816 * args[i].n_aligned_regs);
818 /* Structures smaller than a word are aligned to the least
819 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
820 this means we must skip the empty high order bytes when
821 calculating the bit offset. */
822 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
823 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
825 for (j = 0; j < args[i].n_aligned_regs; j++)
827 rtx reg = gen_reg_rtx (word_mode);
828 rtx word = operand_subword_force (args[i].value, j, BLKmode);
829 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
830 int bitalign = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
832 args[i].aligned_regs[j] = reg;
834 /* There is no need to restrict this code to loading items
835 in TYPE_ALIGN sized hunks. The bitfield instructions can
836 load up entire word sized registers efficiently.
838 ??? This may not be needed anymore.
839 We use to emit a clobber here but that doesn't let later
840 passes optimize the instructions we emit. By storing 0 into
841 the register later passes know the first AND to zero out the
842 bitfield being set in the register is unnecessary. The store
843 of 0 will be deleted as will at least the first AND. */
845 emit_move_insn (reg, const0_rtx);
847 bytes -= bitsize / BITS_PER_UNIT;
848 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
849 extract_bit_field (word, bitsize, 0, 1,
852 bitalign / BITS_PER_UNIT,
854 bitalign / BITS_PER_UNIT, BITS_PER_WORD);
859 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
862 NUM_ACTUALS is the total number of parameters.
864 N_NAMED_ARGS is the total number of named arguments.
866 FNDECL is the tree code for the target of this call (if known)
868 ARGS_SO_FAR holds state needed by the target to know where to place
871 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
872 for arguments which are passed in registers.
874 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
875 and may be modified by this routine.
877 OLD_PENDING_ADJ, MUST_PREALLOCATE and IS_CONST are pointers to integer
878 flags which may may be modified by this routine. */
881 initialize_argument_information (num_actuals, args, args_size, n_named_args,
882 actparms, fndecl, args_so_far,
883 reg_parm_stack_space, old_stack_level,
884 old_pending_adj, must_preallocate, is_const)
885 int num_actuals ATTRIBUTE_UNUSED;
886 struct arg_data *args;
887 struct args_size *args_size;
888 int n_named_args ATTRIBUTE_UNUSED;
891 CUMULATIVE_ARGS *args_so_far;
892 int reg_parm_stack_space;
893 rtx *old_stack_level;
894 int *old_pending_adj;
895 int *must_preallocate;
898 /* 1 if scanning parms front to back, -1 if scanning back to front. */
901 /* Count arg position in order args appear. */
904 struct args_size alignment_pad;
908 args_size->constant = 0;
911 /* In this loop, we consider args in the order they are written.
912 We fill up ARGS from the front or from the back if necessary
913 so that in any case the first arg to be pushed ends up at the front. */
915 #ifdef PUSH_ARGS_REVERSED
916 i = num_actuals - 1, inc = -1;
917 /* In this case, must reverse order of args
918 so that we compute and push the last arg first. */
923 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
924 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
926 tree type = TREE_TYPE (TREE_VALUE (p));
928 enum machine_mode mode;
930 args[i].tree_value = TREE_VALUE (p);
932 /* Replace erroneous argument with constant zero. */
933 if (type == error_mark_node || TYPE_SIZE (type) == 0)
934 args[i].tree_value = integer_zero_node, type = integer_type_node;
936 /* If TYPE is a transparent union, pass things the way we would
937 pass the first field of the union. We have already verified that
938 the modes are the same. */
939 if (TYPE_TRANSPARENT_UNION (type))
940 type = TREE_TYPE (TYPE_FIELDS (type));
942 /* Decide where to pass this arg.
944 args[i].reg is nonzero if all or part is passed in registers.
946 args[i].partial is nonzero if part but not all is passed in registers,
947 and the exact value says how many words are passed in registers.
949 args[i].pass_on_stack is nonzero if the argument must at least be
950 computed on the stack. It may then be loaded back into registers
951 if args[i].reg is nonzero.
953 These decisions are driven by the FUNCTION_... macros and must agree
954 with those made by function.c. */
956 /* See if this argument should be passed by invisible reference. */
957 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
958 && contains_placeholder_p (TYPE_SIZE (type)))
959 || TREE_ADDRESSABLE (type)
960 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
961 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
962 type, argpos < n_named_args)
966 /* If we're compiling a thunk, pass through invisible
967 references instead of making a copy. */
968 if (current_function_is_thunk
969 #ifdef FUNCTION_ARG_CALLEE_COPIES
970 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
971 type, argpos < n_named_args)
972 /* If it's in a register, we must make a copy of it too. */
973 /* ??? Is this a sufficient test? Is there a better one? */
974 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
975 && REG_P (DECL_RTL (args[i].tree_value)))
976 && ! TREE_ADDRESSABLE (type))
980 /* C++ uses a TARGET_EXPR to indicate that we want to make a
981 new object from the argument. If we are passing by
982 invisible reference, the callee will do that for us, so we
983 can strip off the TARGET_EXPR. This is not always safe,
984 but it is safe in the only case where this is a useful
985 optimization; namely, when the argument is a plain object.
986 In that case, the frontend is just asking the backend to
987 make a bitwise copy of the argument. */
989 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
990 && (TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND
991 (args[i].tree_value, 1)))
993 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
994 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
996 args[i].tree_value = build1 (ADDR_EXPR,
997 build_pointer_type (type),
999 type = build_pointer_type (type);
1003 /* We make a copy of the object and pass the address to the
1004 function being called. */
1007 if (TYPE_SIZE (type) == 0
1008 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1009 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1010 && (TREE_INT_CST_HIGH (TYPE_SIZE (type)) != 0
1011 || (TREE_INT_CST_LOW (TYPE_SIZE (type))
1012 > STACK_CHECK_MAX_VAR_SIZE * BITS_PER_UNIT))))
1014 /* This is a variable-sized object. Make space on the stack
1016 rtx size_rtx = expr_size (TREE_VALUE (p));
1018 if (*old_stack_level == 0)
1020 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1021 *old_pending_adj = pending_stack_adjust;
1022 pending_stack_adjust = 0;
1025 copy = gen_rtx_MEM (BLKmode,
1026 allocate_dynamic_stack_space (size_rtx,
1028 TYPE_ALIGN (type)));
1032 int size = int_size_in_bytes (type);
1033 copy = assign_stack_temp (TYPE_MODE (type), size, 0);
1036 MEM_SET_IN_STRUCT_P (copy, AGGREGATE_TYPE_P (type));
1038 store_expr (args[i].tree_value, copy, 0);
1041 args[i].tree_value = build1 (ADDR_EXPR,
1042 build_pointer_type (type),
1043 make_tree (type, copy));
1044 type = build_pointer_type (type);
1048 mode = TYPE_MODE (type);
1049 unsignedp = TREE_UNSIGNED (type);
1051 #ifdef PROMOTE_FUNCTION_ARGS
1052 mode = promote_mode (type, mode, &unsignedp, 1);
1055 args[i].unsignedp = unsignedp;
1056 args[i].mode = mode;
1057 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1058 argpos < n_named_args);
1059 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1062 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1063 argpos < n_named_args);
1066 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1068 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1069 it means that we are to pass this arg in the register(s) designated
1070 by the PARALLEL, but also to pass it in the stack. */
1071 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1072 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1073 args[i].pass_on_stack = 1;
1075 /* If this is an addressable type, we must preallocate the stack
1076 since we must evaluate the object into its final location.
1078 If this is to be passed in both registers and the stack, it is simpler
1080 if (TREE_ADDRESSABLE (type)
1081 || (args[i].pass_on_stack && args[i].reg != 0))
1082 *must_preallocate = 1;
1084 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1085 we cannot consider this function call constant. */
1086 if (TREE_ADDRESSABLE (type))
1089 /* Compute the stack-size of this argument. */
1090 if (args[i].reg == 0 || args[i].partial != 0
1091 || reg_parm_stack_space > 0
1092 || args[i].pass_on_stack)
1093 locate_and_pad_parm (mode, type,
1094 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1099 fndecl, args_size, &args[i].offset,
1100 &args[i].size, &alignment_pad);
1102 #ifndef ARGS_GROW_DOWNWARD
1103 args[i].slot_offset = *args_size;
1106 args[i].alignment_pad = alignment_pad;
1108 /* If a part of the arg was put into registers,
1109 don't include that part in the amount pushed. */
1110 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1111 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1112 / (PARM_BOUNDARY / BITS_PER_UNIT)
1113 * (PARM_BOUNDARY / BITS_PER_UNIT));
1115 /* Update ARGS_SIZE, the total stack space for args so far. */
1117 args_size->constant += args[i].size.constant;
1118 if (args[i].size.var)
1120 ADD_PARM_SIZE (*args_size, args[i].size.var);
1123 /* Since the slot offset points to the bottom of the slot,
1124 we must record it after incrementing if the args grow down. */
1125 #ifdef ARGS_GROW_DOWNWARD
1126 args[i].slot_offset = *args_size;
1128 args[i].slot_offset.constant = -args_size->constant;
1131 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1135 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1136 have been used, etc. */
1138 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1139 argpos < n_named_args);
1143 /* Update ARGS_SIZE to contain the total size for the argument block.
1144 Return the original constant component of the argument block's size.
1146 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1147 for arguments passed in registers. */
1150 compute_argument_block_size (reg_parm_stack_space, args_size)
1151 int reg_parm_stack_space;
1152 struct args_size *args_size;
1154 int unadjusted_args_size = args_size->constant;
1156 /* Compute the actual size of the argument block required. The variable
1157 and constant sizes must be combined, the size may have to be rounded,
1158 and there may be a minimum required size. */
1162 args_size->var = ARGS_SIZE_TREE (*args_size);
1163 args_size->constant = 0;
1165 #ifdef PREFERRED_STACK_BOUNDARY
1166 if (PREFERRED_STACK_BOUNDARY != BITS_PER_UNIT)
1167 args_size->var = round_up (args_size->var, STACK_BYTES);
1170 if (reg_parm_stack_space > 0)
1173 = size_binop (MAX_EXPR, args_size->var,
1174 size_int (reg_parm_stack_space));
1176 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1177 /* The area corresponding to register parameters is not to count in
1178 the size of the block we need. So make the adjustment. */
1180 = size_binop (MINUS_EXPR, args_size->var,
1181 size_int (reg_parm_stack_space));
1187 #ifdef PREFERRED_STACK_BOUNDARY
1188 args_size->constant = (((args_size->constant
1189 + pending_stack_adjust
1191 / STACK_BYTES * STACK_BYTES)
1192 - pending_stack_adjust);
1195 args_size->constant = MAX (args_size->constant,
1196 reg_parm_stack_space);
1198 #ifdef MAYBE_REG_PARM_STACK_SPACE
1199 if (reg_parm_stack_space == 0)
1200 args_size->constant = 0;
1203 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1204 args_size->constant -= reg_parm_stack_space;
1207 return unadjusted_args_size;
1210 /* Precompute parameters as needed for a function call.
1212 IS_CONST indicates the target function is a pure function.
1214 MUST_PREALLOCATE indicates that we must preallocate stack space for
1215 any stack arguments.
1217 NUM_ACTUALS is the number of arguments.
1219 ARGS is an array containing information for each argument; this routine
1220 fills in the INITIAL_VALUE and VALUE fields for each precomputed argument.
1222 ARGS_SIZE contains information about the size of the arg list. */
1225 precompute_arguments (is_const, must_preallocate, num_actuals, args, args_size)
1227 int must_preallocate;
1229 struct arg_data *args;
1230 struct args_size *args_size;
1234 /* If this function call is cse'able, precompute all the parameters.
1235 Note that if the parameter is constructed into a temporary, this will
1236 cause an additional copy because the parameter will be constructed
1237 into a temporary location and then copied into the outgoing arguments.
1238 If a parameter contains a call to alloca and this function uses the
1239 stack, precompute the parameter. */
1241 /* If we preallocated the stack space, and some arguments must be passed
1242 on the stack, then we must precompute any parameter which contains a
1243 function call which will store arguments on the stack.
1244 Otherwise, evaluating the parameter may clobber previous parameters
1245 which have already been stored into the stack. */
1247 for (i = 0; i < num_actuals; i++)
1249 || ((args_size->var != 0 || args_size->constant != 0)
1250 && calls_function (args[i].tree_value, 1))
1251 || (must_preallocate
1252 && (args_size->var != 0 || args_size->constant != 0)
1253 && calls_function (args[i].tree_value, 0)))
1255 /* If this is an addressable type, we cannot pre-evaluate it. */
1256 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1261 args[i].initial_value = args[i].value
1262 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1264 preserve_temp_slots (args[i].value);
1267 /* ANSI doesn't require a sequence point here,
1268 but PCC has one, so this will avoid some problems. */
1271 args[i].initial_value = args[i].value
1272 = protect_from_queue (args[i].initial_value, 0);
1274 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) != args[i].mode)
1276 = convert_modes (args[i].mode,
1277 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1278 args[i].value, args[i].unsignedp);
1282 /* Given the current state of MUST_PREALLOCATE and information about
1283 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1284 compute and return the final value for MUST_PREALLOCATE. */
1287 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1288 int must_preallocate;
1290 struct arg_data *args;
1291 struct args_size *args_size;
1293 /* See if we have or want to preallocate stack space.
1295 If we would have to push a partially-in-regs parm
1296 before other stack parms, preallocate stack space instead.
1298 If the size of some parm is not a multiple of the required stack
1299 alignment, we must preallocate.
1301 If the total size of arguments that would otherwise create a copy in
1302 a temporary (such as a CALL) is more than half the total argument list
1303 size, preallocation is faster.
1305 Another reason to preallocate is if we have a machine (like the m88k)
1306 where stack alignment is required to be maintained between every
1307 pair of insns, not just when the call is made. However, we assume here
1308 that such machines either do not have push insns (and hence preallocation
1309 would occur anyway) or the problem is taken care of with
1312 if (! must_preallocate)
1314 int partial_seen = 0;
1315 int copy_to_evaluate_size = 0;
1318 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1320 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1322 else if (partial_seen && args[i].reg == 0)
1323 must_preallocate = 1;
1325 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1326 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1327 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1328 || TREE_CODE (args[i].tree_value) == COND_EXPR
1329 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1330 copy_to_evaluate_size
1331 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1334 if (copy_to_evaluate_size * 2 >= args_size->constant
1335 && args_size->constant > 0)
1336 must_preallocate = 1;
1338 return must_preallocate;
1341 /* If we preallocated stack space, compute the address of each argument
1342 and store it into the ARGS array.
1344 We need not ensure it is a valid memory address here; it will be
1345 validized when it is used.
1347 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1350 compute_argument_addresses (args, argblock, num_actuals)
1351 struct arg_data *args;
1357 rtx arg_reg = argblock;
1358 int i, arg_offset = 0;
1360 if (GET_CODE (argblock) == PLUS)
1361 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1363 for (i = 0; i < num_actuals; i++)
1365 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1366 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1369 /* Skip this parm if it will not be passed on the stack. */
1370 if (! args[i].pass_on_stack && args[i].reg != 0)
1373 if (GET_CODE (offset) == CONST_INT)
1374 addr = plus_constant (arg_reg, INTVAL (offset));
1376 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1378 addr = plus_constant (addr, arg_offset);
1379 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1382 AGGREGATE_TYPE_P (TREE_TYPE (args[i].tree_value)));
1384 if (GET_CODE (slot_offset) == CONST_INT)
1385 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1387 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1389 addr = plus_constant (addr, arg_offset);
1390 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1395 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1396 in a call instruction.
1398 FNDECL is the tree node for the target function. For an indirect call
1399 FNDECL will be NULL_TREE.
1401 EXP is the CALL_EXPR for this call. */
1404 rtx_for_function_call (fndecl, exp)
1410 /* Get the function to call, in the form of RTL. */
1413 /* If this is the first use of the function, see if we need to
1414 make an external definition for it. */
1415 if (! TREE_USED (fndecl))
1417 assemble_external (fndecl);
1418 TREE_USED (fndecl) = 1;
1421 /* Get a SYMBOL_REF rtx for the function address. */
1422 funexp = XEXP (DECL_RTL (fndecl), 0);
1425 /* Generate an rtx (probably a pseudo-register) for the address. */
1430 expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1431 pop_temp_slots (); /* FUNEXP can't be BLKmode */
1433 /* Check the function is executable. */
1434 if (current_function_check_memory_usage)
1436 #ifdef POINTERS_EXTEND_UNSIGNED
1437 /* It might be OK to convert funexp in place, but there's
1438 a lot going on between here and when it happens naturally
1439 that this seems safer. */
1440 funaddr = convert_memory_address (Pmode, funexp);
1442 emit_library_call (chkr_check_exec_libfunc, 1,
1451 /* Do the register loads required for any wholly-register parms or any
1452 parms which are passed both on the stack and in a register. Their
1453 expressions were already evaluated.
1455 Mark all register-parms as living through the call, putting these USE
1456 insns in the CALL_INSN_FUNCTION_USAGE field. */
1459 load_register_parameters (args, num_actuals, call_fusage)
1460 struct arg_data *args;
1466 #ifdef LOAD_ARGS_REVERSED
1467 for (i = num_actuals - 1; i >= 0; i--)
1469 for (i = 0; i < num_actuals; i++)
1472 rtx reg = args[i].reg;
1473 int partial = args[i].partial;
1478 /* Set to non-negative if must move a word at a time, even if just
1479 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1480 we just use a normal move insn. This value can be zero if the
1481 argument is a zero size structure with no fields. */
1482 nregs = (partial ? partial
1483 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1484 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1485 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1488 /* Handle calls that pass values in multiple non-contiguous
1489 locations. The Irix 6 ABI has examples of this. */
1491 if (GET_CODE (reg) == PARALLEL)
1493 emit_group_load (reg, args[i].value,
1494 int_size_in_bytes (TREE_TYPE (args[i].tree_value)),
1495 (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1499 /* If simple case, just do move. If normal partial, store_one_arg
1500 has already loaded the register for us. In all other cases,
1501 load the register(s) from memory. */
1503 else if (nregs == -1)
1504 emit_move_insn (reg, args[i].value);
1506 /* If we have pre-computed the values to put in the registers in
1507 the case of non-aligned structures, copy them in now. */
1509 else if (args[i].n_aligned_regs != 0)
1510 for (j = 0; j < args[i].n_aligned_regs; j++)
1511 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1512 args[i].aligned_regs[j]);
1514 else if (partial == 0 || args[i].pass_on_stack)
1515 move_block_to_reg (REGNO (reg),
1516 validize_mem (args[i].value), nregs,
1519 /* Handle calls that pass values in multiple non-contiguous
1520 locations. The Irix 6 ABI has examples of this. */
1521 if (GET_CODE (reg) == PARALLEL)
1522 use_group_regs (call_fusage, reg);
1523 else if (nregs == -1)
1524 use_reg (call_fusage, reg);
1526 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1531 /* Generate all the code for a function call
1532 and return an rtx for its value.
1533 Store the value in TARGET (specified as an rtx) if convenient.
1534 If the value is stored in TARGET then TARGET is returned.
1535 If IGNORE is nonzero, then we ignore the value of the function call. */
1538 expand_call (exp, target, ignore)
1543 /* List of actual parameters. */
1544 tree actparms = TREE_OPERAND (exp, 1);
1545 /* RTX for the function to be called. */
1547 /* Data type of the function. */
1549 /* Declaration of the function being called,
1550 or 0 if the function is computed (not known by name). */
1554 /* Register in which non-BLKmode value will be returned,
1555 or 0 if no value or if value is BLKmode. */
1557 /* Address where we should return a BLKmode value;
1558 0 if value not BLKmode. */
1559 rtx structure_value_addr = 0;
1560 /* Nonzero if that address is being passed by treating it as
1561 an extra, implicit first parameter. Otherwise,
1562 it is passed by being copied directly into struct_value_rtx. */
1563 int structure_value_addr_parm = 0;
1564 /* Size of aggregate value wanted, or zero if none wanted
1565 or if we are using the non-reentrant PCC calling convention
1566 or expecting the value in registers. */
1567 HOST_WIDE_INT struct_value_size = 0;
1568 /* Nonzero if called function returns an aggregate in memory PCC style,
1569 by returning the address of where to find it. */
1570 int pcc_struct_value = 0;
1572 /* Number of actual parameters in this call, including struct value addr. */
1574 /* Number of named args. Args after this are anonymous ones
1575 and they must all go on the stack. */
1578 /* Vector of information about each argument.
1579 Arguments are numbered in the order they will be pushed,
1580 not the order they are written. */
1581 struct arg_data *args;
1583 /* Total size in bytes of all the stack-parms scanned so far. */
1584 struct args_size args_size;
1585 /* Size of arguments before any adjustments (such as rounding). */
1586 int unadjusted_args_size;
1587 /* Data on reg parms scanned so far. */
1588 CUMULATIVE_ARGS args_so_far;
1589 /* Nonzero if a reg parm has been scanned. */
1591 /* Nonzero if this is an indirect function call. */
1593 /* Nonzero if we must avoid push-insns in the args for this call.
1594 If stack space is allocated for register parameters, but not by the
1595 caller, then it is preallocated in the fixed part of the stack frame.
1596 So the entire argument block must then be preallocated (i.e., we
1597 ignore PUSH_ROUNDING in that case). */
1599 #ifdef PUSH_ROUNDING
1600 int must_preallocate = 0;
1602 int must_preallocate = 1;
1605 /* Size of the stack reserved for parameter registers. */
1606 int reg_parm_stack_space = 0;
1608 /* Address of space preallocated for stack parms
1609 (on machines that lack push insns), or 0 if space not preallocated. */
1612 /* Nonzero if it is plausible that this is a call to alloca. */
1614 /* Nonzero if this is a call to malloc or a related function. */
1616 /* Nonzero if this is a call to setjmp or a related function. */
1618 /* Nonzero if this is a call to `longjmp'. */
1620 /* Nonzero if this is a call to an inline function. */
1621 int is_integrable = 0;
1622 /* Nonzero if this is a call to a `const' function.
1623 Note that only explicitly named functions are handled as `const' here. */
1625 /* Nonzero if this is a call to a `volatile' function. */
1626 int is_volatile = 0;
1627 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
1628 /* Define the boundary of the register parm stack space that needs to be
1630 int low_to_save = -1, high_to_save;
1631 rtx save_area = 0; /* Place that it is saved */
1634 #ifdef ACCUMULATE_OUTGOING_ARGS
1635 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
1636 char *initial_stack_usage_map = stack_usage_map;
1637 int old_stack_arg_under_construction;
1640 rtx old_stack_level = 0;
1641 int old_pending_adj = 0;
1642 int old_inhibit_defer_pop = inhibit_defer_pop;
1643 rtx call_fusage = 0;
1647 /* The value of the function call can be put in a hard register. But
1648 if -fcheck-memory-usage, code which invokes functions (and thus
1649 damages some hard registers) can be inserted before using the value.
1650 So, target is always a pseudo-register in that case. */
1651 if (current_function_check_memory_usage)
1654 /* See if we can find a DECL-node for the actual function.
1655 As a result, decide whether this is a call to an integrable function. */
1657 p = TREE_OPERAND (exp, 0);
1658 if (TREE_CODE (p) == ADDR_EXPR)
1660 fndecl = TREE_OPERAND (p, 0);
1661 if (TREE_CODE (fndecl) != FUNCTION_DECL)
1666 && fndecl != current_function_decl
1667 && DECL_INLINE (fndecl)
1668 && DECL_SAVED_INSNS (fndecl)
1669 && DECL_SAVED_INSNS (fndecl)->inlinable)
1671 else if (! TREE_ADDRESSABLE (fndecl))
1673 /* In case this function later becomes inlinable,
1674 record that there was already a non-inline call to it.
1676 Use abstraction instead of setting TREE_ADDRESSABLE
1678 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1681 warning_with_decl (fndecl, "can't inline call to `%s'");
1682 warning ("called from here");
1684 mark_addressable (fndecl);
1687 if (TREE_READONLY (fndecl) && ! TREE_THIS_VOLATILE (fndecl)
1688 && TYPE_MODE (TREE_TYPE (exp)) != VOIDmode)
1691 if (TREE_THIS_VOLATILE (fndecl))
1696 /* If we don't have specific function to call, see if we have a
1697 constant or `noreturn' function from the type. */
1700 is_const = TREE_READONLY (TREE_TYPE (TREE_TYPE (p)));
1701 is_volatile = TREE_THIS_VOLATILE (TREE_TYPE (TREE_TYPE (p)));
1704 #ifdef REG_PARM_STACK_SPACE
1705 #ifdef MAYBE_REG_PARM_STACK_SPACE
1706 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1708 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1712 #if defined(PUSH_ROUNDING) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1713 if (reg_parm_stack_space > 0)
1714 must_preallocate = 1;
1717 /* Warn if this value is an aggregate type,
1718 regardless of which calling convention we are using for it. */
1719 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
1720 warning ("function call has aggregate value");
1722 /* Set up a place to return a structure. */
1724 /* Cater to broken compilers. */
1725 if (aggregate_value_p (exp))
1727 /* This call returns a big structure. */
1730 #ifdef PCC_STATIC_STRUCT_RETURN
1732 pcc_struct_value = 1;
1733 /* Easier than making that case work right. */
1736 /* In case this is a static function, note that it has been
1738 if (! TREE_ADDRESSABLE (fndecl))
1739 mark_addressable (fndecl);
1743 #else /* not PCC_STATIC_STRUCT_RETURN */
1745 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
1747 if (target && GET_CODE (target) == MEM)
1748 structure_value_addr = XEXP (target, 0);
1751 /* Assign a temporary to hold the value. */
1754 /* For variable-sized objects, we must be called with a target
1755 specified. If we were to allocate space on the stack here,
1756 we would have no way of knowing when to free it. */
1758 if (struct_value_size < 0)
1761 /* This DECL is just something to feed to mark_addressable;
1762 it doesn't get pushed. */
1763 d = build_decl (VAR_DECL, NULL_TREE, TREE_TYPE (exp));
1764 DECL_RTL (d) = assign_temp (TREE_TYPE (exp), 1, 0, 1);
1765 mark_addressable (d);
1766 structure_value_addr = XEXP (DECL_RTL (d), 0);
1771 #endif /* not PCC_STATIC_STRUCT_RETURN */
1774 /* If called function is inline, try to integrate it. */
1779 #ifdef ACCUMULATE_OUTGOING_ARGS
1780 rtx before_call = get_last_insn ();
1783 temp = expand_inline_function (fndecl, actparms, target,
1784 ignore, TREE_TYPE (exp),
1785 structure_value_addr);
1787 /* If inlining succeeded, return. */
1788 if (temp != (rtx) (HOST_WIDE_INT) -1)
1790 #ifdef ACCUMULATE_OUTGOING_ARGS
1791 /* If the outgoing argument list must be preserved, push
1792 the stack before executing the inlined function if it
1795 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1796 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1799 if (stack_arg_under_construction || i >= 0)
1802 = before_call ? NEXT_INSN (before_call) : get_insns ();
1803 rtx insn = NULL_RTX, seq;
1805 /* Look for a call in the inline function code.
1806 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1807 nonzero then there is a call and it is not necessary
1808 to scan the insns. */
1810 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1811 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1812 if (GET_CODE (insn) == CALL_INSN)
1817 /* Reserve enough stack space so that the largest
1818 argument list of any function call in the inline
1819 function does not overlap the argument list being
1820 evaluated. This is usually an overestimate because
1821 allocate_dynamic_stack_space reserves space for an
1822 outgoing argument list in addition to the requested
1823 space, but there is no way to ask for stack space such
1824 that an argument list of a certain length can be
1827 Add the stack space reserved for register arguments, if
1828 any, in the inline function. What is really needed is the
1829 largest value of reg_parm_stack_space in the inline
1830 function, but that is not available. Using the current
1831 value of reg_parm_stack_space is wrong, but gives
1832 correct results on all supported machines. */
1834 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1835 + reg_parm_stack_space);
1838 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1839 allocate_dynamic_stack_space (GEN_INT (adjust),
1840 NULL_RTX, BITS_PER_UNIT);
1843 emit_insns_before (seq, first_insn);
1844 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1849 /* If the result is equivalent to TARGET, return TARGET to simplify
1850 checks in store_expr. They can be equivalent but not equal in the
1851 case of a function that returns BLKmode. */
1852 if (temp != target && rtx_equal_p (temp, target))
1857 /* If inlining failed, mark FNDECL as needing to be compiled
1858 separately after all. If function was declared inline,
1860 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1861 && optimize > 0 && ! TREE_ADDRESSABLE (fndecl))
1863 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1864 warning ("called from here");
1866 mark_addressable (fndecl);
1869 function_call_count++;
1871 if (fndecl && DECL_NAME (fndecl))
1872 name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
1874 /* See if this is a call to a function that can return more than once
1875 or a call to longjmp or malloc. */
1876 special_function_p (name, fndecl, &returns_twice, &is_longjmp,
1877 &is_malloc, &may_be_alloca);
1880 current_function_calls_alloca = 1;
1882 /* Operand 0 is a pointer-to-function; get the type of the function. */
1883 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
1884 if (! POINTER_TYPE_P (funtype))
1886 funtype = TREE_TYPE (funtype);
1888 /* When calling a const function, we must pop the stack args right away,
1889 so that the pop is deleted or moved with the call. */
1893 /* Don't let pending stack adjusts add up to too much.
1894 Also, do all pending adjustments now
1895 if there is any chance this might be a call to alloca. */
1897 if (pending_stack_adjust >= 32
1898 || (pending_stack_adjust > 0 && may_be_alloca))
1899 do_pending_stack_adjust ();
1901 /* Push the temporary stack slot level so that we can free any temporaries
1905 /* Start updating where the next arg would go.
1907 On some machines (such as the PA) indirect calls have a different
1908 calling convention than normal calls. The last argument in
1909 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
1911 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
1913 /* If struct_value_rtx is 0, it means pass the address
1914 as if it were an extra parameter. */
1915 if (structure_value_addr && struct_value_rtx == 0)
1917 /* If structure_value_addr is a REG other than
1918 virtual_outgoing_args_rtx, we can use always use it. If it
1919 is not a REG, we must always copy it into a register.
1920 If it is virtual_outgoing_args_rtx, we must copy it to another
1921 register in some cases. */
1922 rtx temp = (GET_CODE (structure_value_addr) != REG
1923 #ifdef ACCUMULATE_OUTGOING_ARGS
1924 || (stack_arg_under_construction
1925 && structure_value_addr == virtual_outgoing_args_rtx)
1927 ? copy_addr_to_reg (structure_value_addr)
1928 : structure_value_addr);
1931 = tree_cons (error_mark_node,
1932 make_tree (build_pointer_type (TREE_TYPE (funtype)),
1935 structure_value_addr_parm = 1;
1938 /* Count the arguments and set NUM_ACTUALS. */
1939 for (p = actparms, i = 0; p; p = TREE_CHAIN (p)) i++;
1942 /* Compute number of named args.
1943 Normally, don't include the last named arg if anonymous args follow.
1944 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
1945 (If no anonymous args follow, the result of list_length is actually
1946 one too large. This is harmless.)
1948 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
1949 zero, this machine will be able to place unnamed args that were passed in
1950 registers into the stack. So treat all args as named. This allows the
1951 insns emitting for a specific argument list to be independent of the
1952 function declaration.
1954 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any reliable
1955 way to pass unnamed args in registers, so we must force them into
1958 if ((STRICT_ARGUMENT_NAMING
1959 || ! PRETEND_OUTGOING_VARARGS_NAMED)
1960 && TYPE_ARG_TYPES (funtype) != 0)
1962 = (list_length (TYPE_ARG_TYPES (funtype))
1963 /* Don't include the last named arg. */
1964 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
1965 /* Count the struct value address, if it is passed as a parm. */
1966 + structure_value_addr_parm);
1968 /* If we know nothing, treat all args as named. */
1969 n_named_args = num_actuals;
1971 /* Make a vector to hold all the information about each arg. */
1972 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
1973 bzero ((char *) args, num_actuals * sizeof (struct arg_data));
1975 /* Build up entries inthe ARGS array, compute the size of the arguments
1976 into ARGS_SIZE, etc. */
1977 initialize_argument_information (num_actuals, args, &args_size, n_named_args,
1978 actparms, fndecl, &args_so_far,
1979 reg_parm_stack_space, &old_stack_level,
1980 &old_pending_adj, &must_preallocate,
1983 #ifdef FINAL_REG_PARM_STACK_SPACE
1984 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
1990 /* If this function requires a variable-sized argument list, don't try to
1991 make a cse'able block for this call. We may be able to do this
1992 eventually, but it is too complicated to keep track of what insns go
1993 in the cse'able block and which don't. */
1996 must_preallocate = 1;
1999 /* Compute the actual size of the argument block required. The variable
2000 and constant sizes must be combined, the size may have to be rounded,
2001 and there may be a minimum required size. */
2002 unadjusted_args_size
2003 = compute_argument_block_size (reg_parm_stack_space, &args_size);
2005 /* Now make final decision about preallocating stack space. */
2006 must_preallocate = finalize_must_preallocate (must_preallocate,
2007 num_actuals, args, &args_size);
2009 /* If the structure value address will reference the stack pointer, we must
2010 stabilize it. We don't need to do this if we know that we are not going
2011 to adjust the stack pointer in processing this call. */
2013 if (structure_value_addr
2014 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2015 || reg_mentioned_p (virtual_outgoing_args_rtx, structure_value_addr))
2017 #ifndef ACCUMULATE_OUTGOING_ARGS
2018 || args_size.constant
2021 structure_value_addr = copy_to_reg (structure_value_addr);
2023 /* Precompute any arguments as needed. */
2024 precompute_arguments (is_const, must_preallocate, num_actuals,
2027 /* Now we are about to start emitting insns that can be deleted
2028 if a libcall is deleted. */
2029 if (is_const || is_malloc)
2032 /* If we have no actual push instructions, or shouldn't use them,
2033 make space for all args right now. */
2035 if (args_size.var != 0)
2037 if (old_stack_level == 0)
2039 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2040 old_pending_adj = pending_stack_adjust;
2041 pending_stack_adjust = 0;
2042 #ifdef ACCUMULATE_OUTGOING_ARGS
2043 /* stack_arg_under_construction says whether a stack arg is
2044 being constructed at the old stack level. Pushing the stack
2045 gets a clean outgoing argument block. */
2046 old_stack_arg_under_construction = stack_arg_under_construction;
2047 stack_arg_under_construction = 0;
2050 argblock = push_block (ARGS_SIZE_RTX (args_size), 0, 0);
2054 /* Note that we must go through the motions of allocating an argument
2055 block even if the size is zero because we may be storing args
2056 in the area reserved for register arguments, which may be part of
2059 int needed = args_size.constant;
2061 /* Store the maximum argument space used. It will be pushed by
2062 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2065 if (needed > current_function_outgoing_args_size)
2066 current_function_outgoing_args_size = needed;
2068 if (must_preallocate)
2070 #ifdef ACCUMULATE_OUTGOING_ARGS
2071 /* Since the stack pointer will never be pushed, it is possible for
2072 the evaluation of a parm to clobber something we have already
2073 written to the stack. Since most function calls on RISC machines
2074 do not use the stack, this is uncommon, but must work correctly.
2076 Therefore, we save any area of the stack that was already written
2077 and that we are using. Here we set up to do this by making a new
2078 stack usage map from the old one. The actual save will be done
2081 Another approach might be to try to reorder the argument
2082 evaluations to avoid this conflicting stack usage. */
2084 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2085 /* Since we will be writing into the entire argument area, the
2086 map must be allocated for its entire size, not just the part that
2087 is the responsibility of the caller. */
2088 needed += reg_parm_stack_space;
2091 #ifdef ARGS_GROW_DOWNWARD
2092 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2095 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2098 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
2100 if (initial_highest_arg_in_use)
2101 bcopy (initial_stack_usage_map, stack_usage_map,
2102 initial_highest_arg_in_use);
2104 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2105 bzero (&stack_usage_map[initial_highest_arg_in_use],
2106 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
2109 /* The address of the outgoing argument list must not be copied to a
2110 register here, because argblock would be left pointing to the
2111 wrong place after the call to allocate_dynamic_stack_space below.
2114 argblock = virtual_outgoing_args_rtx;
2116 #else /* not ACCUMULATE_OUTGOING_ARGS */
2117 if (inhibit_defer_pop == 0)
2119 /* Try to reuse some or all of the pending_stack_adjust
2120 to get this space. Maybe we can avoid any pushing. */
2121 if (needed > pending_stack_adjust)
2123 needed -= pending_stack_adjust;
2124 pending_stack_adjust = 0;
2128 pending_stack_adjust -= needed;
2132 /* Special case this because overhead of `push_block' in this
2133 case is non-trivial. */
2135 argblock = virtual_outgoing_args_rtx;
2137 argblock = push_block (GEN_INT (needed), 0, 0);
2139 /* We only really need to call `copy_to_reg' in the case where push
2140 insns are going to be used to pass ARGBLOCK to a function
2141 call in ARGS. In that case, the stack pointer changes value
2142 from the allocation point to the call point, and hence
2143 the value of VIRTUAL_OUTGOING_ARGS_RTX changes as well.
2144 But might as well always do it. */
2145 argblock = copy_to_reg (argblock);
2146 #endif /* not ACCUMULATE_OUTGOING_ARGS */
2150 #ifdef ACCUMULATE_OUTGOING_ARGS
2151 /* The save/restore code in store_one_arg handles all cases except one:
2152 a constructor call (including a C function returning a BLKmode struct)
2153 to initialize an argument. */
2154 if (stack_arg_under_construction)
2156 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2157 rtx push_size = GEN_INT (reg_parm_stack_space + args_size.constant);
2159 rtx push_size = GEN_INT (args_size.constant);
2161 if (old_stack_level == 0)
2163 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2164 old_pending_adj = pending_stack_adjust;
2165 pending_stack_adjust = 0;
2166 /* stack_arg_under_construction says whether a stack arg is
2167 being constructed at the old stack level. Pushing the stack
2168 gets a clean outgoing argument block. */
2169 old_stack_arg_under_construction = stack_arg_under_construction;
2170 stack_arg_under_construction = 0;
2171 /* Make a new map for the new argument list. */
2172 stack_usage_map = (char *)alloca (highest_outgoing_arg_in_use);
2173 bzero (stack_usage_map, highest_outgoing_arg_in_use);
2174 highest_outgoing_arg_in_use = 0;
2176 allocate_dynamic_stack_space (push_size, NULL_RTX, BITS_PER_UNIT);
2178 /* If argument evaluation might modify the stack pointer, copy the
2179 address of the argument list to a register. */
2180 for (i = 0; i < num_actuals; i++)
2181 if (args[i].pass_on_stack)
2183 argblock = copy_addr_to_reg (argblock);
2188 compute_argument_addresses (args, argblock, num_actuals);
2190 #ifdef PUSH_ARGS_REVERSED
2191 #ifdef PREFERRED_STACK_BOUNDARY
2192 /* If we push args individually in reverse order, perform stack alignment
2193 before the first push (the last arg). */
2195 anti_adjust_stack (GEN_INT (args_size.constant - unadjusted_args_size));
2199 /* Don't try to defer pops if preallocating, not even from the first arg,
2200 since ARGBLOCK probably refers to the SP. */
2204 funexp = rtx_for_function_call (fndecl, exp);
2206 /* Figure out the register where the value, if any, will come back. */
2208 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2209 && ! structure_value_addr)
2211 if (pcc_struct_value)
2212 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2215 valreg = hard_function_value (TREE_TYPE (exp), fndecl);
2218 /* Precompute all register parameters. It isn't safe to compute anything
2219 once we have started filling any specific hard regs. */
2220 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2222 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
2224 /* Save the fixed argument area if it's part of the caller's frame and
2225 is clobbered by argument setup for this call. */
2226 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2227 &low_to_save, &high_to_save);
2231 /* Now store (and compute if necessary) all non-register parms.
2232 These come before register parms, since they can require block-moves,
2233 which could clobber the registers used for register parms.
2234 Parms which have partial registers are not stored here,
2235 but we do preallocate space here if they want that. */
2237 for (i = 0; i < num_actuals; i++)
2238 if (args[i].reg == 0 || args[i].pass_on_stack)
2239 store_one_arg (&args[i], argblock, may_be_alloca,
2240 args_size.var != 0, reg_parm_stack_space);
2242 /* If we have a parm that is passed in registers but not in memory
2243 and whose alignment does not permit a direct copy into registers,
2244 make a group of pseudos that correspond to each register that we
2246 if (STRICT_ALIGNMENT)
2247 store_unaligned_arguments_into_pseudos (args, num_actuals);
2249 /* Now store any partially-in-registers parm.
2250 This is the last place a block-move can happen. */
2252 for (i = 0; i < num_actuals; i++)
2253 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2254 store_one_arg (&args[i], argblock, may_be_alloca,
2255 args_size.var != 0, reg_parm_stack_space);
2257 #ifndef PUSH_ARGS_REVERSED
2258 #ifdef PREFERRED_STACK_BOUNDARY
2259 /* If we pushed args in forward order, perform stack alignment
2260 after pushing the last arg. */
2262 anti_adjust_stack (GEN_INT (args_size.constant - unadjusted_args_size));
2266 /* If register arguments require space on the stack and stack space
2267 was not preallocated, allocate stack space here for arguments
2268 passed in registers. */
2269 #if ! defined(ACCUMULATE_OUTGOING_ARGS) && defined(OUTGOING_REG_PARM_STACK_SPACE)
2270 if (must_preallocate == 0 && reg_parm_stack_space > 0)
2271 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
2274 /* Pass the function the address in which to return a structure value. */
2275 if (structure_value_addr && ! structure_value_addr_parm)
2277 emit_move_insn (struct_value_rtx,
2279 force_operand (structure_value_addr,
2282 /* Mark the memory for the aggregate as write-only. */
2283 if (current_function_check_memory_usage)
2284 emit_library_call (chkr_set_right_libfunc, 1,
2286 structure_value_addr, Pmode,
2287 GEN_INT (struct_value_size), TYPE_MODE (sizetype),
2288 GEN_INT (MEMORY_USE_WO),
2289 TYPE_MODE (integer_type_node));
2291 if (GET_CODE (struct_value_rtx) == REG)
2292 use_reg (&call_fusage, struct_value_rtx);
2295 funexp = prepare_call_address (funexp, fndecl, &call_fusage, reg_parm_seen);
2297 load_register_parameters (args, num_actuals, &call_fusage);
2299 /* Perform postincrements before actually calling the function. */
2302 /* All arguments and registers used for the call must be set up by now! */
2304 /* Generate the actual call instruction. */
2305 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
2306 args_size.constant, struct_value_size,
2307 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2308 valreg, old_inhibit_defer_pop, call_fusage, is_const);
2310 /* If call is cse'able, make appropriate pair of reg-notes around it.
2311 Test valreg so we don't crash; may safely ignore `const'
2312 if return type is void. Disable for PARALLEL return values, because
2313 we have no way to move such values into a pseudo register. */
2314 if (is_const && valreg != 0 && GET_CODE (valreg) != PARALLEL)
2317 rtx temp = gen_reg_rtx (GET_MODE (valreg));
2320 /* Mark the return value as a pointer if needed. */
2321 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
2323 tree pointed_to = TREE_TYPE (TREE_TYPE (exp));
2324 mark_reg_pointer (temp, TYPE_ALIGN (pointed_to) / BITS_PER_UNIT);
2327 /* Construct an "equal form" for the value which mentions all the
2328 arguments in order as well as the function name. */
2329 #ifdef PUSH_ARGS_REVERSED
2330 for (i = 0; i < num_actuals; i++)
2331 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
2333 for (i = num_actuals - 1; i >= 0; i--)
2334 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
2336 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
2338 insns = get_insns ();
2341 emit_libcall_block (insns, temp, valreg, note);
2347 /* Otherwise, just write out the sequence without a note. */
2348 rtx insns = get_insns ();
2355 rtx temp = gen_reg_rtx (GET_MODE (valreg));
2358 /* The return value from a malloc-like function is a pointer. */
2359 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
2360 mark_reg_pointer (temp, BIGGEST_ALIGNMENT / BITS_PER_UNIT);
2362 emit_move_insn (temp, valreg);
2364 /* The return value from a malloc-like function can not alias
2366 last = get_last_insn ();
2368 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
2370 /* Write out the sequence. */
2371 insns = get_insns ();
2377 /* For calls to `setjmp', etc., inform flow.c it should complain
2378 if nonvolatile values are live. */
2382 emit_note (name, NOTE_INSN_SETJMP);
2383 current_function_calls_setjmp = 1;
2387 current_function_calls_longjmp = 1;
2389 /* Notice functions that cannot return.
2390 If optimizing, insns emitted below will be dead.
2391 If not optimizing, they will exist, which is useful
2392 if the user uses the `return' command in the debugger. */
2394 if (is_volatile || is_longjmp)
2397 /* If value type not void, return an rtx for the value. */
2399 /* If there are cleanups to be called, don't use a hard reg as target.
2400 We need to double check this and see if it matters anymore. */
2401 if (any_pending_cleanups (1)
2402 && target && REG_P (target)
2403 && REGNO (target) < FIRST_PSEUDO_REGISTER)
2406 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
2409 target = const0_rtx;
2411 else if (structure_value_addr)
2413 if (target == 0 || GET_CODE (target) != MEM)
2415 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
2416 memory_address (TYPE_MODE (TREE_TYPE (exp)),
2417 structure_value_addr));
2418 MEM_SET_IN_STRUCT_P (target,
2419 AGGREGATE_TYPE_P (TREE_TYPE (exp)));
2422 else if (pcc_struct_value)
2424 /* This is the special C++ case where we need to
2425 know what the true target was. We take care to
2426 never use this value more than once in one expression. */
2427 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
2428 copy_to_reg (valreg));
2429 MEM_SET_IN_STRUCT_P (target, AGGREGATE_TYPE_P (TREE_TYPE (exp)));
2431 /* Handle calls that return values in multiple non-contiguous locations.
2432 The Irix 6 ABI has examples of this. */
2433 else if (GET_CODE (valreg) == PARALLEL)
2435 int bytes = int_size_in_bytes (TREE_TYPE (exp));
2439 target = assign_stack_temp (TYPE_MODE (TREE_TYPE (exp)), bytes, 0);
2440 MEM_SET_IN_STRUCT_P (target, AGGREGATE_TYPE_P (TREE_TYPE (exp)));
2441 preserve_temp_slots (target);
2444 if (! rtx_equal_p (target, valreg))
2445 emit_group_store (target, valreg, bytes,
2446 TYPE_ALIGN (TREE_TYPE (exp)) / BITS_PER_UNIT);
2448 else if (target && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
2449 && GET_MODE (target) == GET_MODE (valreg))
2450 /* TARGET and VALREG cannot be equal at this point because the latter
2451 would not have REG_FUNCTION_VALUE_P true, while the former would if
2452 it were referring to the same register.
2454 If they refer to the same register, this move will be a no-op, except
2455 when function inlining is being done. */
2456 emit_move_insn (target, valreg);
2457 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
2458 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
2460 target = copy_to_reg (valreg);
2462 #ifdef PROMOTE_FUNCTION_RETURN
2463 /* If we promoted this return value, make the proper SUBREG. TARGET
2464 might be const0_rtx here, so be careful. */
2465 if (GET_CODE (target) == REG
2466 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
2467 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
2469 tree type = TREE_TYPE (exp);
2470 int unsignedp = TREE_UNSIGNED (type);
2472 /* If we don't promote as expected, something is wrong. */
2473 if (GET_MODE (target)
2474 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
2477 target = gen_rtx_SUBREG (TYPE_MODE (type), target, 0);
2478 SUBREG_PROMOTED_VAR_P (target) = 1;
2479 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
2483 /* If size of args is variable or this was a constructor call for a stack
2484 argument, restore saved stack-pointer value. */
2486 if (old_stack_level)
2488 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
2489 pending_stack_adjust = old_pending_adj;
2490 #ifdef ACCUMULATE_OUTGOING_ARGS
2491 stack_arg_under_construction = old_stack_arg_under_construction;
2492 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2493 stack_usage_map = initial_stack_usage_map;
2496 #ifdef ACCUMULATE_OUTGOING_ARGS
2499 #ifdef REG_PARM_STACK_SPACE
2501 restore_fixed_argument_area (save_area, argblock,
2502 high_to_save, low_to_save);
2505 /* If we saved any argument areas, restore them. */
2506 for (i = 0; i < num_actuals; i++)
2507 if (args[i].save_area)
2509 enum machine_mode save_mode = GET_MODE (args[i].save_area);
2511 = gen_rtx_MEM (save_mode,
2512 memory_address (save_mode,
2513 XEXP (args[i].stack_slot, 0)));
2515 if (save_mode != BLKmode)
2516 emit_move_insn (stack_area, args[i].save_area);
2518 emit_block_move (stack_area, validize_mem (args[i].save_area),
2519 GEN_INT (args[i].size.constant),
2520 PARM_BOUNDARY / BITS_PER_UNIT);
2523 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2524 stack_usage_map = initial_stack_usage_map;
2528 /* If this was alloca, record the new stack level for nonlocal gotos.
2529 Check for the handler slots since we might not have a save area
2530 for non-local gotos. */
2532 if (may_be_alloca && nonlocal_goto_handler_slots != 0)
2533 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
2537 /* Free up storage we no longer need. */
2538 for (i = 0; i < num_actuals; ++i)
2539 if (args[i].aligned_regs)
2540 free (args[i].aligned_regs);
2545 /* Output a library call to function FUN (a SYMBOL_REF rtx)
2546 (emitting the queue unless NO_QUEUE is nonzero),
2547 for a value of mode OUTMODE,
2548 with NARGS different arguments, passed as alternating rtx values
2549 and machine_modes to convert them to.
2550 The rtx values should have been passed through protect_from_queue already.
2552 NO_QUEUE will be true if and only if the library call is a `const' call
2553 which will be enclosed in REG_LIBCALL/REG_RETVAL notes; it is equivalent
2554 to the variable is_const in expand_call.
2556 NO_QUEUE must be true for const calls, because if it isn't, then
2557 any pending increment will be emitted between REG_LIBCALL/REG_RETVAL notes,
2558 and will be lost if the libcall sequence is optimized away.
2560 NO_QUEUE must be false for non-const calls, because if it isn't, the
2561 call insn will have its CONST_CALL_P bit set, and it will be incorrectly
2562 optimized. For instance, the instruction scheduler may incorrectly
2563 move memory references across the non-const call. */
2566 emit_library_call VPROTO((rtx orgfun, int no_queue, enum machine_mode outmode,
2569 #ifndef ANSI_PROTOTYPES
2572 enum machine_mode outmode;
2576 /* Total size in bytes of all the stack-parms scanned so far. */
2577 struct args_size args_size;
2578 /* Size of arguments before any adjustments (such as rounding). */
2579 struct args_size original_args_size;
2580 register int argnum;
2584 struct args_size alignment_pad;
2586 CUMULATIVE_ARGS args_so_far;
2587 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2588 struct args_size offset; struct args_size size; rtx save_area; };
2590 int old_inhibit_defer_pop = inhibit_defer_pop;
2591 rtx call_fusage = 0;
2592 int reg_parm_stack_space = 0;
2593 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
2594 /* Define the boundary of the register parm stack space that needs to be
2596 int low_to_save = -1, high_to_save = 0;
2597 rtx save_area = 0; /* Place that it is saved */
2600 #ifdef ACCUMULATE_OUTGOING_ARGS
2601 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2602 char *initial_stack_usage_map = stack_usage_map;
2606 #ifdef REG_PARM_STACK_SPACE
2607 /* Size of the stack reserved for parameter registers. */
2608 #ifdef MAYBE_REG_PARM_STACK_SPACE
2609 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2611 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
2615 VA_START (p, nargs);
2617 #ifndef ANSI_PROTOTYPES
2618 orgfun = va_arg (p, rtx);
2619 no_queue = va_arg (p, int);
2620 outmode = va_arg (p, enum machine_mode);
2621 nargs = va_arg (p, int);
2626 /* Copy all the libcall-arguments out of the varargs data
2627 and into a vector ARGVEC.
2629 Compute how to pass each argument. We only support a very small subset
2630 of the full argument passing conventions to limit complexity here since
2631 library functions shouldn't have many args. */
2633 argvec = (struct arg *) alloca (nargs * sizeof (struct arg));
2634 bzero ((char *) argvec, nargs * sizeof (struct arg));
2637 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
2639 args_size.constant = 0;
2644 for (count = 0; count < nargs; count++)
2646 rtx val = va_arg (p, rtx);
2647 enum machine_mode mode = va_arg (p, enum machine_mode);
2649 /* We cannot convert the arg value to the mode the library wants here;
2650 must do it earlier where we know the signedness of the arg. */
2652 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2655 /* On some machines, there's no way to pass a float to a library fcn.
2656 Pass it as a double instead. */
2657 #ifdef LIBGCC_NEEDS_DOUBLE
2658 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2659 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
2662 /* There's no need to call protect_from_queue, because
2663 either emit_move_insn or emit_push_insn will do that. */
2665 /* Make sure it is a reasonable operand for a move or push insn. */
2666 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2667 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2668 val = force_operand (val, NULL_RTX);
2670 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2671 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2673 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2674 be viewed as just an efficiency improvement. */
2675 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2676 emit_move_insn (slot, val);
2677 val = force_operand (XEXP (slot, 0), NULL_RTX);
2682 argvec[count].value = val;
2683 argvec[count].mode = mode;
2685 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2686 if (argvec[count].reg && GET_CODE (argvec[count].reg) == PARALLEL)
2688 #ifdef FUNCTION_ARG_PARTIAL_NREGS
2689 argvec[count].partial
2690 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2692 argvec[count].partial = 0;
2695 locate_and_pad_parm (mode, NULL_TREE,
2696 argvec[count].reg && argvec[count].partial == 0,
2697 NULL_TREE, &args_size, &argvec[count].offset,
2698 &argvec[count].size, &alignment_pad);
2700 if (argvec[count].size.var)
2703 if (reg_parm_stack_space == 0 && argvec[count].partial)
2704 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2706 if (argvec[count].reg == 0 || argvec[count].partial != 0
2707 || reg_parm_stack_space > 0)
2708 args_size.constant += argvec[count].size.constant;
2710 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
2714 #ifdef FINAL_REG_PARM_STACK_SPACE
2715 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2719 /* If this machine requires an external definition for library
2720 functions, write one out. */
2721 assemble_external_libcall (fun);
2723 original_args_size = args_size;
2724 #ifdef PREFERRED_STACK_BOUNDARY
2725 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2726 / STACK_BYTES) * STACK_BYTES);
2729 args_size.constant = MAX (args_size.constant,
2730 reg_parm_stack_space);
2732 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2733 args_size.constant -= reg_parm_stack_space;
2736 if (args_size.constant > current_function_outgoing_args_size)
2737 current_function_outgoing_args_size = args_size.constant;
2739 #ifdef ACCUMULATE_OUTGOING_ARGS
2740 /* Since the stack pointer will never be pushed, it is possible for
2741 the evaluation of a parm to clobber something we have already
2742 written to the stack. Since most function calls on RISC machines
2743 do not use the stack, this is uncommon, but must work correctly.
2745 Therefore, we save any area of the stack that was already written
2746 and that we are using. Here we set up to do this by making a new
2747 stack usage map from the old one.
2749 Another approach might be to try to reorder the argument
2750 evaluations to avoid this conflicting stack usage. */
2752 needed = args_size.constant;
2754 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2755 /* Since we will be writing into the entire argument area, the
2756 map must be allocated for its entire size, not just the part that
2757 is the responsibility of the caller. */
2758 needed += reg_parm_stack_space;
2761 #ifdef ARGS_GROW_DOWNWARD
2762 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2765 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2768 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
2770 if (initial_highest_arg_in_use)
2771 bcopy (initial_stack_usage_map, stack_usage_map,
2772 initial_highest_arg_in_use);
2774 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2775 bzero (&stack_usage_map[initial_highest_arg_in_use],
2776 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
2779 /* The address of the outgoing argument list must not be copied to a
2780 register here, because argblock would be left pointing to the
2781 wrong place after the call to allocate_dynamic_stack_space below.
2784 argblock = virtual_outgoing_args_rtx;
2785 #else /* not ACCUMULATE_OUTGOING_ARGS */
2786 #ifndef PUSH_ROUNDING
2787 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2791 #ifdef PUSH_ARGS_REVERSED
2792 #ifdef PREFERRED_STACK_BOUNDARY
2793 /* If we push args individually in reverse order, perform stack alignment
2794 before the first push (the last arg). */
2796 anti_adjust_stack (GEN_INT (args_size.constant
2797 - original_args_size.constant));
2801 #ifdef PUSH_ARGS_REVERSED
2809 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
2810 /* The argument list is the property of the called routine and it
2811 may clobber it. If the fixed area has been used for previous
2812 parameters, we must save and restore it.
2814 Here we compute the boundary of the that needs to be saved, if any. */
2816 #ifdef ARGS_GROW_DOWNWARD
2817 for (count = 0; count < reg_parm_stack_space + 1; count++)
2819 for (count = 0; count < reg_parm_stack_space; count++)
2822 if (count >= highest_outgoing_arg_in_use
2823 || stack_usage_map[count] == 0)
2826 if (low_to_save == -1)
2827 low_to_save = count;
2829 high_to_save = count;
2832 if (low_to_save >= 0)
2834 int num_to_save = high_to_save - low_to_save + 1;
2835 enum machine_mode save_mode
2836 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
2839 /* If we don't have the required alignment, must do this in BLKmode. */
2840 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
2841 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
2842 save_mode = BLKmode;
2844 #ifdef ARGS_GROW_DOWNWARD
2845 stack_area = gen_rtx_MEM (save_mode,
2846 memory_address (save_mode,
2847 plus_constant (argblock,
2850 stack_area = gen_rtx_MEM (save_mode,
2851 memory_address (save_mode,
2852 plus_constant (argblock,
2855 if (save_mode == BLKmode)
2857 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
2858 emit_block_move (validize_mem (save_area), stack_area,
2859 GEN_INT (num_to_save),
2860 PARM_BOUNDARY / BITS_PER_UNIT);
2864 save_area = gen_reg_rtx (save_mode);
2865 emit_move_insn (save_area, stack_area);
2870 /* Push the args that need to be pushed. */
2872 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
2873 are to be pushed. */
2874 for (count = 0; count < nargs; count++, argnum += inc)
2876 register enum machine_mode mode = argvec[argnum].mode;
2877 register rtx val = argvec[argnum].value;
2878 rtx reg = argvec[argnum].reg;
2879 int partial = argvec[argnum].partial;
2880 #ifdef ACCUMULATE_OUTGOING_ARGS
2881 int lower_bound, upper_bound, i;
2884 if (! (reg != 0 && partial == 0))
2886 #ifdef ACCUMULATE_OUTGOING_ARGS
2887 /* If this is being stored into a pre-allocated, fixed-size, stack
2888 area, save any previous data at that location. */
2890 #ifdef ARGS_GROW_DOWNWARD
2891 /* stack_slot is negative, but we want to index stack_usage_map
2892 with positive values. */
2893 upper_bound = -argvec[argnum].offset.constant + 1;
2894 lower_bound = upper_bound - argvec[argnum].size.constant;
2896 lower_bound = argvec[argnum].offset.constant;
2897 upper_bound = lower_bound + argvec[argnum].size.constant;
2900 for (i = lower_bound; i < upper_bound; i++)
2901 if (stack_usage_map[i]
2902 /* Don't store things in the fixed argument area at this point;
2903 it has already been saved. */
2904 && i > reg_parm_stack_space)
2907 if (i != upper_bound)
2909 /* We need to make a save area. See what mode we can make it. */
2910 enum machine_mode save_mode
2911 = mode_for_size (argvec[argnum].size.constant * BITS_PER_UNIT,
2918 plus_constant (argblock,
2919 argvec[argnum].offset.constant)));
2921 argvec[argnum].save_area = gen_reg_rtx (save_mode);
2922 emit_move_insn (argvec[argnum].save_area, stack_area);
2925 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2926 argblock, GEN_INT (argvec[argnum].offset.constant),
2927 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
2929 #ifdef ACCUMULATE_OUTGOING_ARGS
2930 /* Now mark the segment we just used. */
2931 for (i = lower_bound; i < upper_bound; i++)
2932 stack_usage_map[i] = 1;
2939 #ifndef PUSH_ARGS_REVERSED
2940 #ifdef PREFERRED_STACK_BOUNDARY
2941 /* If we pushed args in forward order, perform stack alignment
2942 after pushing the last arg. */
2944 anti_adjust_stack (GEN_INT (args_size.constant
2945 - original_args_size.constant));
2949 #ifdef PUSH_ARGS_REVERSED
2955 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
2957 /* Now load any reg parms into their regs. */
2959 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
2960 are to be pushed. */
2961 for (count = 0; count < nargs; count++, argnum += inc)
2963 register rtx val = argvec[argnum].value;
2964 rtx reg = argvec[argnum].reg;
2965 int partial = argvec[argnum].partial;
2967 if (reg != 0 && partial == 0)
2968 emit_move_insn (reg, val);
2972 /* For version 1.37, try deleting this entirely. */
2976 /* Any regs containing parms remain in use through the call. */
2977 for (count = 0; count < nargs; count++)
2978 if (argvec[count].reg != 0)
2979 use_reg (&call_fusage, argvec[count].reg);
2981 /* Don't allow popping to be deferred, since then
2982 cse'ing of library calls could delete a call and leave the pop. */
2985 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2986 will set inhibit_defer_pop to that value. */
2988 /* The return type is needed to decide how many bytes the function pops.
2989 Signedness plays no role in that, so for simplicity, we pretend it's
2990 always signed. We also assume that the list of arguments passed has
2991 no impact, so we pretend it is unknown. */
2994 get_identifier (XSTR (orgfun, 0)),
2995 build_function_type (outmode == VOIDmode ? void_type_node
2996 : type_for_mode (outmode, 0), NULL_TREE),
2997 original_args_size.constant, args_size.constant, 0,
2998 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2999 outmode != VOIDmode ? hard_libcall_value (outmode) : NULL_RTX,
3000 old_inhibit_defer_pop + 1, call_fusage, no_queue);
3004 /* Now restore inhibit_defer_pop to its actual original value. */
3007 #ifdef ACCUMULATE_OUTGOING_ARGS
3008 #ifdef REG_PARM_STACK_SPACE
3011 enum machine_mode save_mode = GET_MODE (save_area);
3012 #ifdef ARGS_GROW_DOWNWARD
3014 = gen_rtx_MEM (save_mode,
3015 memory_address (save_mode,
3016 plus_constant (argblock,
3020 = gen_rtx_MEM (save_mode,
3021 memory_address (save_mode,
3022 plus_constant (argblock, low_to_save)));
3025 if (save_mode != BLKmode)
3026 emit_move_insn (stack_area, save_area);
3028 emit_block_move (stack_area, validize_mem (save_area),
3029 GEN_INT (high_to_save - low_to_save + 1),
3030 PARM_BOUNDARY / BITS_PER_UNIT);
3034 /* If we saved any argument areas, restore them. */
3035 for (count = 0; count < nargs; count++)
3036 if (argvec[count].save_area)
3038 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
3040 = gen_rtx_MEM (save_mode,
3043 plus_constant (argblock,
3044 argvec[count].offset.constant)));
3046 emit_move_insn (stack_area, argvec[count].save_area);
3049 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3050 stack_usage_map = initial_stack_usage_map;
3054 /* Like emit_library_call except that an extra argument, VALUE,
3055 comes second and says where to store the result.
3056 (If VALUE is zero, this function chooses a convenient way
3057 to return the value.
3059 This function returns an rtx for where the value is to be found.
3060 If VALUE is nonzero, VALUE is returned. */
3063 emit_library_call_value VPROTO((rtx orgfun, rtx value, int no_queue,
3064 enum machine_mode outmode, int nargs, ...))
3066 #ifndef ANSI_PROTOTYPES
3070 enum machine_mode outmode;
3074 /* Total size in bytes of all the stack-parms scanned so far. */
3075 struct args_size args_size;
3076 /* Size of arguments before any adjustments (such as rounding). */
3077 struct args_size original_args_size;
3078 register int argnum;
3082 struct args_size alignment_pad;
3084 CUMULATIVE_ARGS args_so_far;
3085 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
3086 struct args_size offset; struct args_size size; rtx save_area; };
3088 int old_inhibit_defer_pop = inhibit_defer_pop;
3089 rtx call_fusage = 0;
3091 int pcc_struct_value = 0;
3092 int struct_value_size = 0;
3094 int reg_parm_stack_space = 0;
3095 #ifdef ACCUMULATE_OUTGOING_ARGS
3099 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
3100 /* Define the boundary of the register parm stack space that needs to be
3102 int low_to_save = -1, high_to_save = 0;
3103 rtx save_area = 0; /* Place that it is saved */
3106 #ifdef ACCUMULATE_OUTGOING_ARGS
3107 /* Size of the stack reserved for parameter registers. */
3108 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3109 char *initial_stack_usage_map = stack_usage_map;
3112 #ifdef REG_PARM_STACK_SPACE
3113 #ifdef MAYBE_REG_PARM_STACK_SPACE
3114 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3116 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3120 VA_START (p, nargs);
3122 #ifndef ANSI_PROTOTYPES
3123 orgfun = va_arg (p, rtx);
3124 value = va_arg (p, rtx);
3125 no_queue = va_arg (p, int);
3126 outmode = va_arg (p, enum machine_mode);
3127 nargs = va_arg (p, int);
3130 is_const = no_queue;
3133 /* If this kind of value comes back in memory,
3134 decide where in memory it should come back. */
3135 if (aggregate_value_p (type_for_mode (outmode, 0)))
3137 #ifdef PCC_STATIC_STRUCT_RETURN
3139 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
3141 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3142 pcc_struct_value = 1;
3144 value = gen_reg_rtx (outmode);
3145 #else /* not PCC_STATIC_STRUCT_RETURN */
3146 struct_value_size = GET_MODE_SIZE (outmode);
3147 if (value != 0 && GET_CODE (value) == MEM)
3150 mem_value = assign_stack_temp (outmode, GET_MODE_SIZE (outmode), 0);
3153 /* This call returns a big structure. */
3157 /* ??? Unfinished: must pass the memory address as an argument. */
3159 /* Copy all the libcall-arguments out of the varargs data
3160 and into a vector ARGVEC.
3162 Compute how to pass each argument. We only support a very small subset
3163 of the full argument passing conventions to limit complexity here since
3164 library functions shouldn't have many args. */
3166 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3167 bzero ((char *) argvec, (nargs + 1) * sizeof (struct arg));
3169 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3171 args_size.constant = 0;
3178 /* If there's a structure value address to be passed,
3179 either pass it in the special place, or pass it as an extra argument. */
3180 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3182 rtx addr = XEXP (mem_value, 0);
3185 /* Make sure it is a reasonable operand for a move or push insn. */
3186 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3187 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3188 addr = force_operand (addr, NULL_RTX);
3190 argvec[count].value = addr;
3191 argvec[count].mode = Pmode;
3192 argvec[count].partial = 0;
3194 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3195 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3196 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3200 locate_and_pad_parm (Pmode, NULL_TREE,
3201 argvec[count].reg && argvec[count].partial == 0,
3202 NULL_TREE, &args_size, &argvec[count].offset,
3203 &argvec[count].size, &alignment_pad);
3206 if (argvec[count].reg == 0 || argvec[count].partial != 0
3207 || reg_parm_stack_space > 0)
3208 args_size.constant += argvec[count].size.constant;
3210 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3215 for (; count < nargs; count++)
3217 rtx val = va_arg (p, rtx);
3218 enum machine_mode mode = va_arg (p, enum machine_mode);
3220 /* We cannot convert the arg value to the mode the library wants here;
3221 must do it earlier where we know the signedness of the arg. */
3223 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3226 /* On some machines, there's no way to pass a float to a library fcn.
3227 Pass it as a double instead. */
3228 #ifdef LIBGCC_NEEDS_DOUBLE
3229 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3230 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3233 /* There's no need to call protect_from_queue, because
3234 either emit_move_insn or emit_push_insn will do that. */
3236 /* Make sure it is a reasonable operand for a move or push insn. */
3237 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3238 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3239 val = force_operand (val, NULL_RTX);
3241 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3242 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3244 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
3245 be viewed as just an efficiency improvement. */
3246 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
3247 emit_move_insn (slot, val);
3248 val = XEXP (slot, 0);
3253 argvec[count].value = val;
3254 argvec[count].mode = mode;
3256 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3257 if (argvec[count].reg && GET_CODE (argvec[count].reg) == PARALLEL)
3259 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3260 argvec[count].partial
3261 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3263 argvec[count].partial = 0;
3266 locate_and_pad_parm (mode, NULL_TREE,
3267 argvec[count].reg && argvec[count].partial == 0,
3268 NULL_TREE, &args_size, &argvec[count].offset,
3269 &argvec[count].size, &alignment_pad);
3271 if (argvec[count].size.var)
3274 if (reg_parm_stack_space == 0 && argvec[count].partial)
3275 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3277 if (argvec[count].reg == 0 || argvec[count].partial != 0
3278 || reg_parm_stack_space > 0)
3279 args_size.constant += argvec[count].size.constant;
3281 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3285 #ifdef FINAL_REG_PARM_STACK_SPACE
3286 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3289 /* If this machine requires an external definition for library
3290 functions, write one out. */
3291 assemble_external_libcall (fun);
3293 original_args_size = args_size;
3294 #ifdef PREFERRED_STACK_BOUNDARY
3295 args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
3296 / STACK_BYTES) * STACK_BYTES);
3299 args_size.constant = MAX (args_size.constant,
3300 reg_parm_stack_space);
3302 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3303 args_size.constant -= reg_parm_stack_space;
3306 if (args_size.constant > current_function_outgoing_args_size)
3307 current_function_outgoing_args_size = args_size.constant;
3309 #ifdef ACCUMULATE_OUTGOING_ARGS
3310 /* Since the stack pointer will never be pushed, it is possible for
3311 the evaluation of a parm to clobber something we have already
3312 written to the stack. Since most function calls on RISC machines
3313 do not use the stack, this is uncommon, but must work correctly.
3315 Therefore, we save any area of the stack that was already written
3316 and that we are using. Here we set up to do this by making a new
3317 stack usage map from the old one.
3319 Another approach might be to try to reorder the argument
3320 evaluations to avoid this conflicting stack usage. */
3322 needed = args_size.constant;
3324 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3325 /* Since we will be writing into the entire argument area, the
3326 map must be allocated for its entire size, not just the part that
3327 is the responsibility of the caller. */
3328 needed += reg_parm_stack_space;
3331 #ifdef ARGS_GROW_DOWNWARD
3332 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3335 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3338 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3340 if (initial_highest_arg_in_use)
3341 bcopy (initial_stack_usage_map, stack_usage_map,
3342 initial_highest_arg_in_use);
3344 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3345 bzero (&stack_usage_map[initial_highest_arg_in_use],
3346 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3349 /* The address of the outgoing argument list must not be copied to a
3350 register here, because argblock would be left pointing to the
3351 wrong place after the call to allocate_dynamic_stack_space below.
3354 argblock = virtual_outgoing_args_rtx;
3355 #else /* not ACCUMULATE_OUTGOING_ARGS */
3356 #ifndef PUSH_ROUNDING
3357 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3361 #ifdef PUSH_ARGS_REVERSED
3362 #ifdef PREFERRED_STACK_BOUNDARY
3363 /* If we push args individually in reverse order, perform stack alignment
3364 before the first push (the last arg). */
3366 anti_adjust_stack (GEN_INT (args_size.constant
3367 - original_args_size.constant));
3371 #ifdef PUSH_ARGS_REVERSED
3379 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
3380 /* The argument list is the property of the called routine and it
3381 may clobber it. If the fixed area has been used for previous
3382 parameters, we must save and restore it.
3384 Here we compute the boundary of the that needs to be saved, if any. */
3386 #ifdef ARGS_GROW_DOWNWARD
3387 for (count = 0; count < reg_parm_stack_space + 1; count++)
3389 for (count = 0; count < reg_parm_stack_space; count++)
3392 if (count >= highest_outgoing_arg_in_use
3393 || stack_usage_map[count] == 0)
3396 if (low_to_save == -1)
3397 low_to_save = count;
3399 high_to_save = count;
3402 if (low_to_save >= 0)
3404 int num_to_save = high_to_save - low_to_save + 1;
3405 enum machine_mode save_mode
3406 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3409 /* If we don't have the required alignment, must do this in BLKmode. */
3410 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3411 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3412 save_mode = BLKmode;
3414 #ifdef ARGS_GROW_DOWNWARD
3415 stack_area = gen_rtx_MEM (save_mode,
3416 memory_address (save_mode,
3417 plus_constant (argblock,
3420 stack_area = gen_rtx_MEM (save_mode,
3421 memory_address (save_mode,
3422 plus_constant (argblock,
3425 if (save_mode == BLKmode)
3427 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3428 emit_block_move (validize_mem (save_area), stack_area,
3429 GEN_INT (num_to_save),
3430 PARM_BOUNDARY / BITS_PER_UNIT);
3434 save_area = gen_reg_rtx (save_mode);
3435 emit_move_insn (save_area, stack_area);
3440 /* Push the args that need to be pushed. */
3442 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3443 are to be pushed. */
3444 for (count = 0; count < nargs; count++, argnum += inc)
3446 register enum machine_mode mode = argvec[argnum].mode;
3447 register rtx val = argvec[argnum].value;
3448 rtx reg = argvec[argnum].reg;
3449 int partial = argvec[argnum].partial;
3450 #ifdef ACCUMULATE_OUTGOING_ARGS
3451 int lower_bound, upper_bound, i;
3454 if (! (reg != 0 && partial == 0))
3456 #ifdef ACCUMULATE_OUTGOING_ARGS
3457 /* If this is being stored into a pre-allocated, fixed-size, stack
3458 area, save any previous data at that location. */
3460 #ifdef ARGS_GROW_DOWNWARD
3461 /* stack_slot is negative, but we want to index stack_usage_map
3462 with positive values. */
3463 upper_bound = -argvec[argnum].offset.constant + 1;
3464 lower_bound = upper_bound - argvec[argnum].size.constant;
3466 lower_bound = argvec[argnum].offset.constant;
3467 upper_bound = lower_bound + argvec[argnum].size.constant;
3470 for (i = lower_bound; i < upper_bound; i++)
3471 if (stack_usage_map[i]
3472 /* Don't store things in the fixed argument area at this point;
3473 it has already been saved. */
3474 && i > reg_parm_stack_space)
3477 if (i != upper_bound)
3479 /* We need to make a save area. See what mode we can make it. */
3480 enum machine_mode save_mode
3481 = mode_for_size (argvec[argnum].size.constant * BITS_PER_UNIT,
3488 plus_constant (argblock,
3489 argvec[argnum].offset.constant)));
3490 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3492 emit_move_insn (argvec[argnum].save_area, stack_area);
3495 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
3496 argblock, GEN_INT (argvec[argnum].offset.constant),
3497 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3499 #ifdef ACCUMULATE_OUTGOING_ARGS
3500 /* Now mark the segment we just used. */
3501 for (i = lower_bound; i < upper_bound; i++)
3502 stack_usage_map[i] = 1;
3509 #ifndef PUSH_ARGS_REVERSED
3510 #ifdef PREFERRED_STACK_BOUNDARY
3511 /* If we pushed args in forward order, perform stack alignment
3512 after pushing the last arg. */
3514 anti_adjust_stack (GEN_INT (args_size.constant
3515 - original_args_size.constant));
3519 #ifdef PUSH_ARGS_REVERSED
3525 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
3527 /* Now load any reg parms into their regs. */
3529 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3530 are to be pushed. */
3531 for (count = 0; count < nargs; count++, argnum += inc)
3533 register rtx val = argvec[argnum].value;
3534 rtx reg = argvec[argnum].reg;
3535 int partial = argvec[argnum].partial;
3537 if (reg != 0 && partial == 0)
3538 emit_move_insn (reg, val);
3543 /* For version 1.37, try deleting this entirely. */
3548 /* Any regs containing parms remain in use through the call. */
3549 for (count = 0; count < nargs; count++)
3550 if (argvec[count].reg != 0)
3551 use_reg (&call_fusage, argvec[count].reg);
3553 /* Pass the function the address in which to return a structure value. */
3554 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
3556 emit_move_insn (struct_value_rtx,
3558 force_operand (XEXP (mem_value, 0),
3560 if (GET_CODE (struct_value_rtx) == REG)
3561 use_reg (&call_fusage, struct_value_rtx);
3564 /* Don't allow popping to be deferred, since then
3565 cse'ing of library calls could delete a call and leave the pop. */
3568 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3569 will set inhibit_defer_pop to that value. */
3570 /* See the comment in emit_library_call about the function type we build
3574 get_identifier (XSTR (orgfun, 0)),
3575 build_function_type (type_for_mode (outmode, 0), NULL_TREE),
3576 original_args_size.constant, args_size.constant,
3578 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
3579 mem_value == 0 ? hard_libcall_value (outmode) : NULL_RTX,
3580 old_inhibit_defer_pop + 1, call_fusage, is_const);
3582 /* Now restore inhibit_defer_pop to its actual original value. */
3587 /* Copy the value to the right place. */
3588 if (outmode != VOIDmode)
3594 if (value != mem_value)
3595 emit_move_insn (value, mem_value);
3597 else if (value != 0)
3598 emit_move_insn (value, hard_libcall_value (outmode));
3600 value = hard_libcall_value (outmode);
3603 #ifdef ACCUMULATE_OUTGOING_ARGS
3604 #ifdef REG_PARM_STACK_SPACE
3607 enum machine_mode save_mode = GET_MODE (save_area);
3608 #ifdef ARGS_GROW_DOWNWARD
3610 = gen_rtx_MEM (save_mode,
3611 memory_address (save_mode,
3612 plus_constant (argblock,
3616 = gen_rtx_MEM (save_mode,
3617 memory_address (save_mode,
3618 plus_constant (argblock, low_to_save)));
3620 if (save_mode != BLKmode)
3621 emit_move_insn (stack_area, save_area);
3623 emit_block_move (stack_area, validize_mem (save_area),
3624 GEN_INT (high_to_save - low_to_save + 1),
3625 PARM_BOUNDARY / BITS_PER_UNIT);
3629 /* If we saved any argument areas, restore them. */
3630 for (count = 0; count < nargs; count++)
3631 if (argvec[count].save_area)
3633 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
3635 = gen_rtx_MEM (save_mode,
3638 plus_constant (argblock,
3639 argvec[count].offset.constant)));
3641 emit_move_insn (stack_area, argvec[count].save_area);
3644 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3645 stack_usage_map = initial_stack_usage_map;
3652 /* Return an rtx which represents a suitable home on the stack
3653 given TYPE, the type of the argument looking for a home.
3654 This is called only for BLKmode arguments.
3656 SIZE is the size needed for this target.
3657 ARGS_ADDR is the address of the bottom of the argument block for this call.
3658 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
3659 if this machine uses push insns. */
3662 target_for_arg (type, size, args_addr, offset)
3666 struct args_size offset;
3669 rtx offset_rtx = ARGS_SIZE_RTX (offset);
3671 /* We do not call memory_address if possible,
3672 because we want to address as close to the stack
3673 as possible. For non-variable sized arguments,
3674 this will be stack-pointer relative addressing. */
3675 if (GET_CODE (offset_rtx) == CONST_INT)
3676 target = plus_constant (args_addr, INTVAL (offset_rtx));
3679 /* I have no idea how to guarantee that this
3680 will work in the presence of register parameters. */
3681 target = gen_rtx_PLUS (Pmode, args_addr, offset_rtx);
3682 target = memory_address (QImode, target);
3685 return gen_rtx_MEM (BLKmode, target);
3689 /* Store a single argument for a function call
3690 into the register or memory area where it must be passed.
3691 *ARG describes the argument value and where to pass it.
3693 ARGBLOCK is the address of the stack-block for all the arguments,
3694 or 0 on a machine where arguments are pushed individually.
3696 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
3697 so must be careful about how the stack is used.
3699 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
3700 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
3701 that we need not worry about saving and restoring the stack.
3703 FNDECL is the declaration of the function we are calling. */
3706 store_one_arg (arg, argblock, may_be_alloca, variable_size,
3707 reg_parm_stack_space)
3708 struct arg_data *arg;
3711 int variable_size ATTRIBUTE_UNUSED;
3712 int reg_parm_stack_space;
3714 register tree pval = arg->tree_value;
3718 #ifdef ACCUMULATE_OUTGOING_ARGS
3719 int i, lower_bound = 0, upper_bound = 0;
3722 if (TREE_CODE (pval) == ERROR_MARK)
3725 /* Push a new temporary level for any temporaries we make for
3729 #ifdef ACCUMULATE_OUTGOING_ARGS
3730 /* If this is being stored into a pre-allocated, fixed-size, stack area,
3731 save any previous data at that location. */
3732 if (argblock && ! variable_size && arg->stack)
3734 #ifdef ARGS_GROW_DOWNWARD
3735 /* stack_slot is negative, but we want to index stack_usage_map
3736 with positive values. */
3737 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
3738 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
3742 lower_bound = upper_bound - arg->size.constant;
3744 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
3745 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
3749 upper_bound = lower_bound + arg->size.constant;
3752 for (i = lower_bound; i < upper_bound; i++)
3753 if (stack_usage_map[i]
3754 /* Don't store things in the fixed argument area at this point;
3755 it has already been saved. */
3756 && i > reg_parm_stack_space)
3759 if (i != upper_bound)
3761 /* We need to make a save area. See what mode we can make it. */
3762 enum machine_mode save_mode
3763 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
3765 = gen_rtx_MEM (save_mode,
3766 memory_address (save_mode,
3767 XEXP (arg->stack_slot, 0)));
3769 if (save_mode == BLKmode)
3771 arg->save_area = assign_stack_temp (BLKmode,
3772 arg->size.constant, 0);
3773 MEM_SET_IN_STRUCT_P (arg->save_area,
3774 AGGREGATE_TYPE_P (TREE_TYPE
3775 (arg->tree_value)));
3776 preserve_temp_slots (arg->save_area);
3777 emit_block_move (validize_mem (arg->save_area), stack_area,
3778 GEN_INT (arg->size.constant),
3779 PARM_BOUNDARY / BITS_PER_UNIT);
3783 arg->save_area = gen_reg_rtx (save_mode);
3784 emit_move_insn (arg->save_area, stack_area);
3789 /* Now that we have saved any slots that will be overwritten by this
3790 store, mark all slots this store will use. We must do this before
3791 we actually expand the argument since the expansion itself may
3792 trigger library calls which might need to use the same stack slot. */
3793 if (argblock && ! variable_size && arg->stack)
3794 for (i = lower_bound; i < upper_bound; i++)
3795 stack_usage_map[i] = 1;
3798 /* If this isn't going to be placed on both the stack and in registers,
3799 set up the register and number of words. */
3800 if (! arg->pass_on_stack)
3801 reg = arg->reg, partial = arg->partial;
3803 if (reg != 0 && partial == 0)
3804 /* Being passed entirely in a register. We shouldn't be called in
3808 /* If this arg needs special alignment, don't load the registers
3810 if (arg->n_aligned_regs != 0)
3813 /* If this is being passed partially in a register, we can't evaluate
3814 it directly into its stack slot. Otherwise, we can. */
3815 if (arg->value == 0)
3817 #ifdef ACCUMULATE_OUTGOING_ARGS
3818 /* stack_arg_under_construction is nonzero if a function argument is
3819 being evaluated directly into the outgoing argument list and
3820 expand_call must take special action to preserve the argument list
3821 if it is called recursively.
3823 For scalar function arguments stack_usage_map is sufficient to
3824 determine which stack slots must be saved and restored. Scalar
3825 arguments in general have pass_on_stack == 0.
3827 If this argument is initialized by a function which takes the
3828 address of the argument (a C++ constructor or a C function
3829 returning a BLKmode structure), then stack_usage_map is
3830 insufficient and expand_call must push the stack around the
3831 function call. Such arguments have pass_on_stack == 1.
3833 Note that it is always safe to set stack_arg_under_construction,
3834 but this generates suboptimal code if set when not needed. */
3836 if (arg->pass_on_stack)
3837 stack_arg_under_construction++;
3839 arg->value = expand_expr (pval,
3841 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
3842 ? NULL_RTX : arg->stack,
3845 /* If we are promoting object (or for any other reason) the mode
3846 doesn't agree, convert the mode. */
3848 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
3849 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
3850 arg->value, arg->unsignedp);
3852 #ifdef ACCUMULATE_OUTGOING_ARGS
3853 if (arg->pass_on_stack)
3854 stack_arg_under_construction--;
3858 /* Don't allow anything left on stack from computation
3859 of argument to alloca. */
3861 do_pending_stack_adjust ();
3863 if (arg->value == arg->stack)
3865 /* If the value is already in the stack slot, we are done. */
3866 if (current_function_check_memory_usage && GET_CODE (arg->stack) == MEM)
3868 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
3869 XEXP (arg->stack, 0), Pmode,
3870 ARGS_SIZE_RTX (arg->size),
3871 TYPE_MODE (sizetype),
3872 GEN_INT (MEMORY_USE_RW),
3873 TYPE_MODE (integer_type_node));
3876 else if (arg->mode != BLKmode)
3880 /* Argument is a scalar, not entirely passed in registers.
3881 (If part is passed in registers, arg->partial says how much
3882 and emit_push_insn will take care of putting it there.)
3884 Push it, and if its size is less than the
3885 amount of space allocated to it,
3886 also bump stack pointer by the additional space.
3887 Note that in C the default argument promotions
3888 will prevent such mismatches. */
3890 size = GET_MODE_SIZE (arg->mode);
3891 /* Compute how much space the push instruction will push.
3892 On many machines, pushing a byte will advance the stack
3893 pointer by a halfword. */
3894 #ifdef PUSH_ROUNDING
3895 size = PUSH_ROUNDING (size);
3899 /* Compute how much space the argument should get:
3900 round up to a multiple of the alignment for arguments. */
3901 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
3902 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
3903 / (PARM_BOUNDARY / BITS_PER_UNIT))
3904 * (PARM_BOUNDARY / BITS_PER_UNIT));
3906 /* This isn't already where we want it on the stack, so put it there.
3907 This can either be done with push or copy insns. */
3908 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX, 0,
3909 partial, reg, used - size, argblock,
3910 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
3911 ARGS_SIZE_RTX (arg->alignment_pad));
3916 /* BLKmode, at least partly to be pushed. */
3918 register int excess;
3921 /* Pushing a nonscalar.
3922 If part is passed in registers, PARTIAL says how much
3923 and emit_push_insn will take care of putting it there. */
3925 /* Round its size up to a multiple
3926 of the allocation unit for arguments. */
3928 if (arg->size.var != 0)
3931 size_rtx = ARGS_SIZE_RTX (arg->size);
3935 /* PUSH_ROUNDING has no effect on us, because
3936 emit_push_insn for BLKmode is careful to avoid it. */
3937 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
3938 + partial * UNITS_PER_WORD);
3939 size_rtx = expr_size (pval);
3942 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
3943 TYPE_ALIGN (TREE_TYPE (pval)) / BITS_PER_UNIT, partial,
3944 reg, excess, argblock, ARGS_SIZE_RTX (arg->offset),
3945 reg_parm_stack_space,
3946 ARGS_SIZE_RTX (arg->alignment_pad));
3950 /* Unless this is a partially-in-register argument, the argument is now
3953 ??? Note that this can change arg->value from arg->stack to
3954 arg->stack_slot and it matters when they are not the same.
3955 It isn't totally clear that this is correct in all cases. */
3957 arg->value = arg->stack_slot;
3959 /* Once we have pushed something, pops can't safely
3960 be deferred during the rest of the arguments. */
3963 /* ANSI doesn't require a sequence point here,
3964 but PCC has one, so this will avoid some problems. */
3967 /* Free any temporary slots made in processing this argument. Show
3968 that we might have taken the address of something and pushed that
3970 preserve_temp_slots (NULL_RTX);