1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998
3 1999, 2000 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
30 #include "insn-flags.h"
35 #ifndef ACCUMULATE_OUTGOING_ARGS
36 #define ACCUMULATE_OUTGOING_ARGS 0
39 /* Supply a default definition for PUSH_ARGS. */
42 #define PUSH_ARGS !ACCUMULATE_OUTGOING_ARGS
48 #if !defined FUNCTION_OK_FOR_SIBCALL
49 #define FUNCTION_OK_FOR_SIBCALL(DECL) 1
52 #if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY
53 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
56 /* Decide whether a function's arguments should be processed
57 from first to last or from last to first.
59 They should if the stack and args grow in opposite directions, but
60 only if we have push insns. */
64 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
65 #define PUSH_ARGS_REVERSED PUSH_ARGS
70 #ifndef PUSH_ARGS_REVERSED
71 #define PUSH_ARGS_REVERSED 0
74 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
75 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
77 /* Data structure and subroutines used within expand_call. */
81 /* Tree node for this argument. */
83 /* Mode for value; TYPE_MODE unless promoted. */
84 enum machine_mode mode;
85 /* Current RTL value for argument, or 0 if it isn't precomputed. */
87 /* Initially-compute RTL value for argument; only for const functions. */
89 /* Register to pass this argument in, 0 if passed on stack, or an
90 PARALLEL if the arg is to be copied into multiple non-contiguous
93 /* If REG was promoted from the actual mode of the argument expression,
94 indicates whether the promotion is sign- or zero-extended. */
96 /* Number of registers to use. 0 means put the whole arg in registers.
97 Also 0 if not passed in registers. */
99 /* Non-zero if argument must be passed on stack.
100 Note that some arguments may be passed on the stack
101 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
102 pass_on_stack identifies arguments that *cannot* go in registers. */
104 /* Offset of this argument from beginning of stack-args. */
105 struct args_size offset;
106 /* Similar, but offset to the start of the stack slot. Different from
107 OFFSET if this arg pads downward. */
108 struct args_size slot_offset;
109 /* Size of this argument on the stack, rounded up for any padding it gets,
110 parts of the argument passed in registers do not count.
111 If REG_PARM_STACK_SPACE is defined, then register parms
112 are counted here as well. */
113 struct args_size size;
114 /* Location on the stack at which parameter should be stored. The store
115 has already been done if STACK == VALUE. */
117 /* Location on the stack of the start of this argument slot. This can
118 differ from STACK if this arg pads downward. This location is known
119 to be aligned to FUNCTION_ARG_BOUNDARY. */
121 /* Place that this stack area has been saved, if needed. */
123 /* If an argument's alignment does not permit direct copying into registers,
124 copy in smaller-sized pieces into pseudos. These are stored in a
125 block pointed to by this field. The next field says how many
126 word-sized pseudos we made. */
129 /* The amount that the stack pointer needs to be adjusted to
130 force alignment for the next argument. */
131 struct args_size alignment_pad;
134 /* A vector of one char per byte of stack space. A byte if non-zero if
135 the corresponding stack location has been used.
136 This vector is used to prevent a function call within an argument from
137 clobbering any stack already set up. */
138 static char *stack_usage_map;
140 /* Size of STACK_USAGE_MAP. */
141 static int highest_outgoing_arg_in_use;
143 /* stack_arg_under_construction is nonzero when an argument may be
144 initialized with a constructor call (including a C function that
145 returns a BLKmode struct) and expand_call must take special action
146 to make sure the object being constructed does not overlap the
147 argument list for the constructor call. */
148 int stack_arg_under_construction;
150 static int calls_function PARAMS ((tree, int));
151 static int calls_function_1 PARAMS ((tree, int));
153 /* Nonzero if this is a call to a `const' function. */
155 /* Nonzero if this is a call to a `volatile' function. */
156 #define ECF_NORETURN 2
157 /* Nonzero if this is a call to malloc or a related function. */
159 /* Nonzero if it is plausible that this is a call to alloca. */
160 #define ECF_MAY_BE_ALLOCA 8
161 /* Nonzero if this is a call to a function that won't throw an exception. */
162 #define ECF_NOTHROW 16
163 /* Nonzero if this is a call to setjmp or a related function. */
164 #define ECF_RETURNS_TWICE 32
165 /* Nonzero if this is a call to `longjmp'. */
166 #define ECF_LONGJMP 64
167 /* Nonzero if this is a syscall that makes a new process in the image of
169 #define ECF_FORK_OR_EXEC 128
170 #define ECF_SIBCALL 256
171 /* Nonzero if this is a call to "pure" function (like const function,
172 but may read memory. */
175 static void emit_call_1 PARAMS ((rtx, tree, tree, HOST_WIDE_INT,
176 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
177 rtx, int, rtx, int));
178 static void precompute_register_parameters PARAMS ((int,
181 static void store_one_arg PARAMS ((struct arg_data *, rtx, int, int,
183 static void store_unaligned_arguments_into_pseudos PARAMS ((struct arg_data *,
185 static int finalize_must_preallocate PARAMS ((int, int,
187 struct args_size *));
188 static void precompute_arguments PARAMS ((int, int,
190 static int compute_argument_block_size PARAMS ((int,
193 static void initialize_argument_information PARAMS ((int,
200 static void compute_argument_addresses PARAMS ((struct arg_data *,
202 static rtx rtx_for_function_call PARAMS ((tree, tree));
203 static void load_register_parameters PARAMS ((struct arg_data *,
205 static int libfunc_nothrow PARAMS ((rtx));
206 static rtx emit_library_call_value_1 PARAMS ((int, rtx, rtx, int,
209 static int special_function_p PARAMS ((tree, int));
210 static int flags_from_decl_or_type PARAMS ((tree));
211 static rtx try_to_integrate PARAMS ((tree, tree, rtx,
213 static void combine_pending_stack_adjustment_and_call
214 PARAMS ((int, struct args_size *, int));
216 #ifdef REG_PARM_STACK_SPACE
217 static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
218 static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
221 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
224 If WHICH is 0, return 1 if EXP contains a call to any function.
225 Actually, we only need return 1 if evaluating EXP would require pushing
226 arguments on the stack, but that is too difficult to compute, so we just
227 assume any function call might require the stack. */
229 static tree calls_function_save_exprs;
232 calls_function (exp, which)
237 calls_function_save_exprs = 0;
238 val = calls_function_1 (exp, which);
239 calls_function_save_exprs = 0;
244 calls_function_1 (exp, which)
249 enum tree_code code = TREE_CODE (exp);
250 int type = TREE_CODE_CLASS (code);
251 int length = tree_code_length[(int) code];
253 /* If this code is language-specific, we don't know what it will do. */
254 if ((int) code >= NUM_TREE_CODES)
257 /* Only expressions and references can contain calls. */
258 if (type != 'e' && type != '<' && type != '1' && type != '2' && type != 'r'
267 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
268 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
271 tree fndecl = TREE_OPERAND (TREE_OPERAND (exp, 0), 0);
273 if ((DECL_BUILT_IN (fndecl)
274 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
275 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_ALLOCA)
276 || (DECL_SAVED_INSNS (fndecl)
277 && DECL_SAVED_INSNS (fndecl)->calls_alloca))
281 /* Third operand is RTL. */
286 if (SAVE_EXPR_RTL (exp) != 0)
288 if (value_member (exp, calls_function_save_exprs))
290 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
291 calls_function_save_exprs);
292 return (TREE_OPERAND (exp, 0) != 0
293 && calls_function_1 (TREE_OPERAND (exp, 0), which));
299 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
300 if (DECL_INITIAL (local) != 0
301 && calls_function_1 (DECL_INITIAL (local), which))
305 register tree subblock;
307 for (subblock = BLOCK_SUBBLOCKS (exp);
309 subblock = TREE_CHAIN (subblock))
310 if (calls_function_1 (subblock, which))
315 case METHOD_CALL_EXPR:
319 case WITH_CLEANUP_EXPR:
330 for (i = 0; i < length; i++)
331 if (TREE_OPERAND (exp, i) != 0
332 && calls_function_1 (TREE_OPERAND (exp, i), which))
338 /* Force FUNEXP into a form suitable for the address of a CALL,
339 and return that as an rtx. Also load the static chain register
340 if FNDECL is a nested function.
342 CALL_FUSAGE points to a variable holding the prospective
343 CALL_INSN_FUNCTION_USAGE information. */
346 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen)
352 rtx static_chain_value = 0;
354 funexp = protect_from_queue (funexp, 0);
357 /* Get possible static chain value for nested function in C. */
358 static_chain_value = lookup_static_chain (fndecl);
360 /* Make a valid memory address and copy constants thru pseudo-regs,
361 but not for a constant address if -fno-function-cse. */
362 if (GET_CODE (funexp) != SYMBOL_REF)
363 /* If we are using registers for parameters, force the
364 function address into a register now. */
365 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
366 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
367 : memory_address (FUNCTION_MODE, funexp));
370 #ifndef NO_FUNCTION_CSE
371 if (optimize && ! flag_no_function_cse)
372 #ifdef NO_RECURSIVE_FUNCTION_CSE
373 if (fndecl != current_function_decl)
375 funexp = force_reg (Pmode, funexp);
379 if (static_chain_value != 0)
381 emit_move_insn (static_chain_rtx, static_chain_value);
383 if (GET_CODE (static_chain_rtx) == REG)
384 use_reg (call_fusage, static_chain_rtx);
390 /* Generate instructions to call function FUNEXP,
391 and optionally pop the results.
392 The CALL_INSN is the first insn generated.
394 FNDECL is the declaration node of the function. This is given to the
395 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
397 FUNTYPE is the data type of the function. This is given to the macro
398 RETURN_POPS_ARGS to determine whether this function pops its own args.
399 We used to allow an identifier for library functions, but that doesn't
400 work when the return type is an aggregate type and the calling convention
401 says that the pointer to this aggregate is to be popped by the callee.
403 STACK_SIZE is the number of bytes of arguments on the stack,
404 ROUNDED_STACK_SIZE is that number rounded up to
405 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
406 both to put into the call insn and to generate explicit popping
409 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
410 It is zero if this call doesn't want a structure value.
412 NEXT_ARG_REG is the rtx that results from executing
413 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
414 just after all the args have had their registers assigned.
415 This could be whatever you like, but normally it is the first
416 arg-register beyond those used for args in this call,
417 or 0 if all the arg-registers are used in this call.
418 It is passed on to `gen_call' so you can put this info in the call insn.
420 VALREG is a hard register in which a value is returned,
421 or 0 if the call does not return a value.
423 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
424 the args to this call were processed.
425 We restore `inhibit_defer_pop' to that value.
427 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
428 denote registers used by the called function. */
431 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
432 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
433 call_fusage, ecf_flags)
435 tree fndecl ATTRIBUTE_UNUSED;
436 tree funtype ATTRIBUTE_UNUSED;
437 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
438 HOST_WIDE_INT rounded_stack_size;
439 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
442 int old_inhibit_defer_pop;
446 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
447 #if defined (HAVE_call) && defined (HAVE_call_value)
448 rtx struct_value_size_rtx = GEN_INT (struct_value_size);
451 int already_popped = 0;
452 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
454 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
455 and we don't want to load it into a register as an optimization,
456 because prepare_call_address already did it if it should be done. */
457 if (GET_CODE (funexp) != SYMBOL_REF)
458 funexp = memory_address (FUNCTION_MODE, funexp);
460 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
461 if ((ecf_flags & ECF_SIBCALL)
462 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
463 && (RETURN_POPS_ARGS (fndecl, funtype, stack_size) > 0
466 rtx n_pop = GEN_INT (RETURN_POPS_ARGS (fndecl, funtype, stack_size));
469 /* If this subroutine pops its own args, record that in the call insn
470 if possible, for the sake of frame pointer elimination. */
473 pat = gen_sibcall_value_pop (valreg,
474 gen_rtx_MEM (FUNCTION_MODE, funexp),
475 rounded_stack_size_rtx, next_arg_reg,
478 pat = gen_sibcall_pop (gen_rtx_MEM (FUNCTION_MODE, funexp),
479 rounded_stack_size_rtx, next_arg_reg, n_pop);
481 emit_call_insn (pat);
487 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
488 /* If the target has "call" or "call_value" insns, then prefer them
489 if no arguments are actually popped. If the target does not have
490 "call" or "call_value" insns, then we must use the popping versions
491 even if the call has no arguments to pop. */
492 #if defined (HAVE_call) && defined (HAVE_call_value)
493 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
496 if (HAVE_call_pop && HAVE_call_value_pop)
499 rtx n_pop = GEN_INT (n_popped);
502 /* If this subroutine pops its own args, record that in the call insn
503 if possible, for the sake of frame pointer elimination. */
506 pat = gen_call_value_pop (valreg,
507 gen_rtx_MEM (FUNCTION_MODE, funexp),
508 rounded_stack_size_rtx, next_arg_reg, n_pop);
510 pat = gen_call_pop (gen_rtx_MEM (FUNCTION_MODE, funexp),
511 rounded_stack_size_rtx, next_arg_reg, n_pop);
513 emit_call_insn (pat);
519 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
520 if ((ecf_flags & ECF_SIBCALL)
521 && HAVE_sibcall && HAVE_sibcall_value)
524 emit_call_insn (gen_sibcall_value (valreg,
525 gen_rtx_MEM (FUNCTION_MODE, funexp),
526 rounded_stack_size_rtx,
527 next_arg_reg, NULL_RTX));
529 emit_call_insn (gen_sibcall (gen_rtx_MEM (FUNCTION_MODE, funexp),
530 rounded_stack_size_rtx, next_arg_reg,
531 struct_value_size_rtx));
536 #if defined (HAVE_call) && defined (HAVE_call_value)
537 if (HAVE_call && HAVE_call_value)
540 emit_call_insn (gen_call_value (valreg,
541 gen_rtx_MEM (FUNCTION_MODE, funexp),
542 rounded_stack_size_rtx, next_arg_reg,
545 emit_call_insn (gen_call (gen_rtx_MEM (FUNCTION_MODE, funexp),
546 rounded_stack_size_rtx, next_arg_reg,
547 struct_value_size_rtx));
553 /* Find the CALL insn we just emitted. */
554 for (call_insn = get_last_insn ();
555 call_insn && GET_CODE (call_insn) != CALL_INSN;
556 call_insn = PREV_INSN (call_insn))
562 /* Mark memory as used for "pure" function call. */
563 if (ecf_flags & ECF_PURE)
565 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
566 gen_rtx_USE (VOIDmode,
567 gen_rtx_MEM (BLKmode,
568 gen_rtx_SCRATCH (VOIDmode))), call_fusage);
571 /* Put the register usage information on the CALL. If there is already
572 some usage information, put ours at the end. */
573 if (CALL_INSN_FUNCTION_USAGE (call_insn))
577 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
578 link = XEXP (link, 1))
581 XEXP (link, 1) = call_fusage;
584 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
586 /* If this is a const call, then set the insn's unchanging bit. */
587 if (ecf_flags & (ECF_CONST | ECF_PURE))
588 CONST_CALL_P (call_insn) = 1;
590 /* If this call can't throw, attach a REG_EH_REGION reg note to that
592 if (ecf_flags & ECF_NOTHROW)
593 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
594 REG_NOTES (call_insn));
596 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
598 /* Restore this now, so that we do defer pops for this call's args
599 if the context of the call as a whole permits. */
600 inhibit_defer_pop = old_inhibit_defer_pop;
605 CALL_INSN_FUNCTION_USAGE (call_insn)
606 = gen_rtx_EXPR_LIST (VOIDmode,
607 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
608 CALL_INSN_FUNCTION_USAGE (call_insn));
609 rounded_stack_size -= n_popped;
610 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
611 stack_pointer_delta -= n_popped;
614 if (!ACCUMULATE_OUTGOING_ARGS)
616 /* If returning from the subroutine does not automatically pop the args,
617 we need an instruction to pop them sooner or later.
618 Perhaps do it now; perhaps just record how much space to pop later.
620 If returning from the subroutine does pop the args, indicate that the
621 stack pointer will be changed. */
623 if (rounded_stack_size != 0)
625 if (flag_defer_pop && inhibit_defer_pop == 0
626 && !(ecf_flags & (ECF_CONST | ECF_PURE)))
627 pending_stack_adjust += rounded_stack_size;
629 adjust_stack (rounded_stack_size_rtx);
632 /* When we accumulate outgoing args, we must avoid any stack manipulations.
633 Restore the stack pointer to its original value now. Usually
634 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
635 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
636 popping variants of functions exist as well.
638 ??? We may optimize similar to defer_pop above, but it is
639 probably not worthwhile.
641 ??? It will be worthwhile to enable combine_stack_adjustments even for
644 anti_adjust_stack (GEN_INT (n_popped));
647 /* Determine if the function identified by NAME and FNDECL is one with
648 special properties we wish to know about.
650 For example, if the function might return more than one time (setjmp), then
651 set RETURNS_TWICE to a nonzero value.
653 Similarly set LONGJMP for if the function is in the longjmp family.
655 Set MALLOC for any of the standard memory allocation functions which
656 allocate from the heap.
658 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
659 space from the stack such as alloca. */
662 special_function_p (fndecl, flags)
666 if (! (flags & ECF_MALLOC)
667 && fndecl && DECL_NAME (fndecl)
668 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
669 /* Exclude functions not at the file scope, or not `extern',
670 since they are not the magic functions we would otherwise
672 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
674 char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
677 /* We assume that alloca will always be called by name. It
678 makes no sense to pass it as a pointer-to-function to
679 anything that does not understand its behavior. */
680 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
682 && ! strcmp (name, "alloca"))
683 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
685 && ! strcmp (name, "__builtin_alloca"))))
686 flags |= ECF_MAY_BE_ALLOCA;
688 /* Disregard prefix _, __ or __x. */
691 if (name[1] == '_' && name[2] == 'x')
693 else if (name[1] == '_')
702 && (! strcmp (tname, "setjmp")
703 || ! strcmp (tname, "setjmp_syscall")))
705 && ! strcmp (tname, "sigsetjmp"))
707 && ! strcmp (tname, "savectx")))
708 flags |= ECF_RETURNS_TWICE;
711 && ! strcmp (tname, "siglongjmp"))
712 flags |= ECF_LONGJMP;
714 else if ((tname[0] == 'q' && tname[1] == 's'
715 && ! strcmp (tname, "qsetjmp"))
716 || (tname[0] == 'v' && tname[1] == 'f'
717 && ! strcmp (tname, "vfork")))
718 flags |= ECF_RETURNS_TWICE;
720 else if (tname[0] == 'l' && tname[1] == 'o'
721 && ! strcmp (tname, "longjmp"))
722 flags |= ECF_LONGJMP;
724 else if ((tname[0] == 'f' && tname[1] == 'o'
725 && ! strcmp (tname, "fork"))
726 /* Linux specific: __clone. check NAME to insist on the
727 leading underscores, to avoid polluting the ISO / POSIX
729 || (name[0] == '_' && name[1] == '_'
730 && ! strcmp (tname, "clone"))
731 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
732 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
734 || ((tname[5] == 'p' || tname[5] == 'e')
735 && tname[6] == '\0'))))
736 flags |= ECF_FORK_OR_EXEC;
738 /* Do not add any more malloc-like functions to this list,
739 instead mark them as malloc functions using the malloc attribute.
740 Note, realloc is not suitable for attribute malloc since
741 it may return the same address across multiple calls.
742 C++ operator new is not suitable because it is not required
743 to return a unique pointer; indeed, the standard placement new
744 just returns its argument. */
745 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl))) == Pmode
746 && (! strcmp (tname, "malloc")
747 || ! strcmp (tname, "calloc")
748 || ! strcmp (tname, "strdup")))
754 /* Return nonzero when tree represent call to longjmp. */
756 setjmp_call_p (fndecl)
759 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
762 /* Detect flags (function attributes) from the function type node. */
764 flags_from_decl_or_type (exp)
768 /* ??? We can't set IS_MALLOC for function types? */
771 /* The function exp may have the `malloc' attribute. */
772 if (DECL_P (exp) && DECL_IS_MALLOC (exp))
775 /* The function exp may have the `pure' attribute. */
776 if (DECL_P (exp) && DECL_IS_PURE (exp))
779 if (TREE_NOTHROW (exp))
780 flags |= ECF_NOTHROW;
783 if (TREE_READONLY (exp) && !TREE_THIS_VOLATILE (exp))
786 if (TREE_THIS_VOLATILE (exp))
787 flags |= ECF_NORETURN;
793 /* Precompute all register parameters as described by ARGS, storing values
794 into fields within the ARGS array.
796 NUM_ACTUALS indicates the total number elements in the ARGS array.
798 Set REG_PARM_SEEN if we encounter a register parameter. */
801 precompute_register_parameters (num_actuals, args, reg_parm_seen)
803 struct arg_data *args;
810 for (i = 0; i < num_actuals; i++)
811 if (args[i].reg != 0 && ! args[i].pass_on_stack)
815 if (args[i].value == 0)
818 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
820 preserve_temp_slots (args[i].value);
823 /* ANSI doesn't require a sequence point here,
824 but PCC has one, so this will avoid some problems. */
828 /* If we are to promote the function arg to a wider mode,
831 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
833 = convert_modes (args[i].mode,
834 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
835 args[i].value, args[i].unsignedp);
837 /* If the value is expensive, and we are inside an appropriately
838 short loop, put the value into a pseudo and then put the pseudo
841 For small register classes, also do this if this call uses
842 register parameters. This is to avoid reload conflicts while
843 loading the parameters registers. */
845 if ((! (GET_CODE (args[i].value) == REG
846 || (GET_CODE (args[i].value) == SUBREG
847 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
848 && args[i].mode != BLKmode
849 && rtx_cost (args[i].value, SET) > 2
850 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
851 || preserve_subexpressions_p ()))
852 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
856 #ifdef REG_PARM_STACK_SPACE
858 /* The argument list is the property of the called routine and it
859 may clobber it. If the fixed area has been used for previous
860 parameters, we must save and restore it. */
862 save_fixed_argument_area (reg_parm_stack_space, argblock,
863 low_to_save, high_to_save)
864 int reg_parm_stack_space;
870 rtx save_area = NULL_RTX;
872 /* Compute the boundary of the that needs to be saved, if any. */
873 #ifdef ARGS_GROW_DOWNWARD
874 for (i = 0; i < reg_parm_stack_space + 1; i++)
876 for (i = 0; i < reg_parm_stack_space; i++)
879 if (i >= highest_outgoing_arg_in_use
880 || stack_usage_map[i] == 0)
883 if (*low_to_save == -1)
889 if (*low_to_save >= 0)
891 int num_to_save = *high_to_save - *low_to_save + 1;
892 enum machine_mode save_mode
893 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
896 /* If we don't have the required alignment, must do this in BLKmode. */
897 if ((*low_to_save & (MIN (GET_MODE_SIZE (save_mode),
898 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
901 #ifdef ARGS_GROW_DOWNWARD
902 stack_area = gen_rtx_MEM (save_mode,
903 memory_address (save_mode,
904 plus_constant (argblock,
907 stack_area = gen_rtx_MEM (save_mode,
908 memory_address (save_mode,
909 plus_constant (argblock,
912 if (save_mode == BLKmode)
914 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
915 /* Cannot use emit_block_move here because it can be done by a
916 library call which in turn gets into this place again and deadly
917 infinite recursion happens. */
918 move_by_pieces (validize_mem (save_area), stack_area, num_to_save,
923 save_area = gen_reg_rtx (save_mode);
924 emit_move_insn (save_area, stack_area);
931 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
937 enum machine_mode save_mode = GET_MODE (save_area);
938 #ifdef ARGS_GROW_DOWNWARD
940 = gen_rtx_MEM (save_mode,
941 memory_address (save_mode,
942 plus_constant (argblock,
946 = gen_rtx_MEM (save_mode,
947 memory_address (save_mode,
948 plus_constant (argblock,
952 if (save_mode != BLKmode)
953 emit_move_insn (stack_area, save_area);
955 /* Cannot use emit_block_move here because it can be done by a library
956 call which in turn gets into this place again and deadly infinite
957 recursion happens. */
958 move_by_pieces (stack_area, validize_mem (save_area),
959 high_to_save - low_to_save + 1, PARM_BOUNDARY);
963 /* If any elements in ARGS refer to parameters that are to be passed in
964 registers, but not in memory, and whose alignment does not permit a
965 direct copy into registers. Copy the values into a group of pseudos
966 which we will later copy into the appropriate hard registers.
968 Pseudos for each unaligned argument will be stored into the array
969 args[argnum].aligned_regs. The caller is responsible for deallocating
970 the aligned_regs array if it is nonzero. */
973 store_unaligned_arguments_into_pseudos (args, num_actuals)
974 struct arg_data *args;
979 for (i = 0; i < num_actuals; i++)
980 if (args[i].reg != 0 && ! args[i].pass_on_stack
981 && args[i].mode == BLKmode
982 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
983 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
985 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
986 int big_endian_correction = 0;
988 args[i].n_aligned_regs
989 = args[i].partial ? args[i].partial
990 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
992 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
993 * args[i].n_aligned_regs);
995 /* Structures smaller than a word are aligned to the least
996 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
997 this means we must skip the empty high order bytes when
998 calculating the bit offset. */
999 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
1000 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1002 for (j = 0; j < args[i].n_aligned_regs; j++)
1004 rtx reg = gen_reg_rtx (word_mode);
1005 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1006 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1007 int bitalign = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
1009 args[i].aligned_regs[j] = reg;
1011 /* There is no need to restrict this code to loading items
1012 in TYPE_ALIGN sized hunks. The bitfield instructions can
1013 load up entire word sized registers efficiently.
1015 ??? This may not be needed anymore.
1016 We use to emit a clobber here but that doesn't let later
1017 passes optimize the instructions we emit. By storing 0 into
1018 the register later passes know the first AND to zero out the
1019 bitfield being set in the register is unnecessary. The store
1020 of 0 will be deleted as will at least the first AND. */
1022 emit_move_insn (reg, const0_rtx);
1024 bytes -= bitsize / BITS_PER_UNIT;
1025 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
1026 extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1027 word_mode, word_mode, bitalign,
1029 bitalign, BITS_PER_WORD);
1034 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1037 NUM_ACTUALS is the total number of parameters.
1039 N_NAMED_ARGS is the total number of named arguments.
1041 FNDECL is the tree code for the target of this call (if known)
1043 ARGS_SO_FAR holds state needed by the target to know where to place
1046 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1047 for arguments which are passed in registers.
1049 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1050 and may be modified by this routine.
1052 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1053 flags which may may be modified by this routine. */
1056 initialize_argument_information (num_actuals, args, args_size, n_named_args,
1057 actparms, fndecl, args_so_far,
1058 reg_parm_stack_space, old_stack_level,
1059 old_pending_adj, must_preallocate,
1061 int num_actuals ATTRIBUTE_UNUSED;
1062 struct arg_data *args;
1063 struct args_size *args_size;
1064 int n_named_args ATTRIBUTE_UNUSED;
1067 CUMULATIVE_ARGS *args_so_far;
1068 int reg_parm_stack_space;
1069 rtx *old_stack_level;
1070 int *old_pending_adj;
1071 int *must_preallocate;
1074 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1077 /* Count arg position in order args appear. */
1080 struct args_size alignment_pad;
1084 args_size->constant = 0;
1087 /* In this loop, we consider args in the order they are written.
1088 We fill up ARGS from the front or from the back if necessary
1089 so that in any case the first arg to be pushed ends up at the front. */
1091 if (PUSH_ARGS_REVERSED)
1093 i = num_actuals - 1, inc = -1;
1094 /* In this case, must reverse order of args
1095 so that we compute and push the last arg first. */
1102 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1103 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1105 tree type = TREE_TYPE (TREE_VALUE (p));
1107 enum machine_mode mode;
1109 args[i].tree_value = TREE_VALUE (p);
1111 /* Replace erroneous argument with constant zero. */
1112 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1113 args[i].tree_value = integer_zero_node, type = integer_type_node;
1115 /* If TYPE is a transparent union, pass things the way we would
1116 pass the first field of the union. We have already verified that
1117 the modes are the same. */
1118 if (TYPE_TRANSPARENT_UNION (type))
1119 type = TREE_TYPE (TYPE_FIELDS (type));
1121 /* Decide where to pass this arg.
1123 args[i].reg is nonzero if all or part is passed in registers.
1125 args[i].partial is nonzero if part but not all is passed in registers,
1126 and the exact value says how many words are passed in registers.
1128 args[i].pass_on_stack is nonzero if the argument must at least be
1129 computed on the stack. It may then be loaded back into registers
1130 if args[i].reg is nonzero.
1132 These decisions are driven by the FUNCTION_... macros and must agree
1133 with those made by function.c. */
1135 /* See if this argument should be passed by invisible reference. */
1136 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1137 && contains_placeholder_p (TYPE_SIZE (type)))
1138 || TREE_ADDRESSABLE (type)
1139 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1140 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1141 type, argpos < n_named_args)
1145 /* If we're compiling a thunk, pass through invisible
1146 references instead of making a copy. */
1147 if (current_function_is_thunk
1148 #ifdef FUNCTION_ARG_CALLEE_COPIES
1149 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1150 type, argpos < n_named_args)
1151 /* If it's in a register, we must make a copy of it too. */
1152 /* ??? Is this a sufficient test? Is there a better one? */
1153 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1154 && REG_P (DECL_RTL (args[i].tree_value)))
1155 && ! TREE_ADDRESSABLE (type))
1159 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1160 new object from the argument. If we are passing by
1161 invisible reference, the callee will do that for us, so we
1162 can strip off the TARGET_EXPR. This is not always safe,
1163 but it is safe in the only case where this is a useful
1164 optimization; namely, when the argument is a plain object.
1165 In that case, the frontend is just asking the backend to
1166 make a bitwise copy of the argument. */
1168 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1169 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1170 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1171 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1173 args[i].tree_value = build1 (ADDR_EXPR,
1174 build_pointer_type (type),
1175 args[i].tree_value);
1176 type = build_pointer_type (type);
1180 /* We make a copy of the object and pass the address to the
1181 function being called. */
1184 if (!COMPLETE_TYPE_P (type)
1185 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1186 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1187 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1188 STACK_CHECK_MAX_VAR_SIZE))))
1190 /* This is a variable-sized object. Make space on the stack
1192 rtx size_rtx = expr_size (TREE_VALUE (p));
1194 if (*old_stack_level == 0)
1196 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1197 *old_pending_adj = pending_stack_adjust;
1198 pending_stack_adjust = 0;
1201 copy = gen_rtx_MEM (BLKmode,
1202 allocate_dynamic_stack_space (size_rtx,
1204 TYPE_ALIGN (type)));
1208 int size = int_size_in_bytes (type);
1209 copy = assign_stack_temp (TYPE_MODE (type), size, 0);
1212 MEM_SET_IN_STRUCT_P (copy, AGGREGATE_TYPE_P (type));
1214 store_expr (args[i].tree_value, copy, 0);
1215 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1217 args[i].tree_value = build1 (ADDR_EXPR,
1218 build_pointer_type (type),
1219 make_tree (type, copy));
1220 type = build_pointer_type (type);
1224 mode = TYPE_MODE (type);
1225 unsignedp = TREE_UNSIGNED (type);
1227 #ifdef PROMOTE_FUNCTION_ARGS
1228 mode = promote_mode (type, mode, &unsignedp, 1);
1231 args[i].unsignedp = unsignedp;
1232 args[i].mode = mode;
1234 #ifdef FUNCTION_INCOMING_ARG
1235 /* If this is a sibling call and the machine has register windows, the
1236 register window has to be unwinded before calling the routine, so
1237 arguments have to go into the incoming registers. */
1238 if (*ecf_flags & ECF_SIBCALL)
1239 args[i].reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1240 argpos < n_named_args);
1243 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1244 argpos < n_named_args);
1246 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1249 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1250 argpos < n_named_args);
1253 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1255 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1256 it means that we are to pass this arg in the register(s) designated
1257 by the PARALLEL, but also to pass it in the stack. */
1258 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1259 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1260 args[i].pass_on_stack = 1;
1262 /* If this is an addressable type, we must preallocate the stack
1263 since we must evaluate the object into its final location.
1265 If this is to be passed in both registers and the stack, it is simpler
1267 if (TREE_ADDRESSABLE (type)
1268 || (args[i].pass_on_stack && args[i].reg != 0))
1269 *must_preallocate = 1;
1271 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1272 we cannot consider this function call constant. */
1273 if (TREE_ADDRESSABLE (type))
1274 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1276 /* Compute the stack-size of this argument. */
1277 if (args[i].reg == 0 || args[i].partial != 0
1278 || reg_parm_stack_space > 0
1279 || args[i].pass_on_stack)
1280 locate_and_pad_parm (mode, type,
1281 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1286 fndecl, args_size, &args[i].offset,
1287 &args[i].size, &alignment_pad);
1289 #ifndef ARGS_GROW_DOWNWARD
1290 args[i].slot_offset = *args_size;
1293 args[i].alignment_pad = alignment_pad;
1295 /* If a part of the arg was put into registers,
1296 don't include that part in the amount pushed. */
1297 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1298 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1299 / (PARM_BOUNDARY / BITS_PER_UNIT)
1300 * (PARM_BOUNDARY / BITS_PER_UNIT));
1302 /* Update ARGS_SIZE, the total stack space for args so far. */
1304 args_size->constant += args[i].size.constant;
1305 if (args[i].size.var)
1307 ADD_PARM_SIZE (*args_size, args[i].size.var);
1310 /* Since the slot offset points to the bottom of the slot,
1311 we must record it after incrementing if the args grow down. */
1312 #ifdef ARGS_GROW_DOWNWARD
1313 args[i].slot_offset = *args_size;
1315 args[i].slot_offset.constant = -args_size->constant;
1317 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1320 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1321 have been used, etc. */
1323 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1324 argpos < n_named_args);
1328 /* Update ARGS_SIZE to contain the total size for the argument block.
1329 Return the original constant component of the argument block's size.
1331 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1332 for arguments passed in registers. */
1335 compute_argument_block_size (reg_parm_stack_space, args_size,
1336 preferred_stack_boundary)
1337 int reg_parm_stack_space;
1338 struct args_size *args_size;
1339 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1341 int unadjusted_args_size = args_size->constant;
1343 /* For accumulate outgoing args mode we don't need to align, since the frame
1344 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1345 backends from generating missaligned frame sizes. */
1346 #ifdef STACK_BOUNDARY
1347 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1348 preferred_stack_boundary = STACK_BOUNDARY;
1351 /* Compute the actual size of the argument block required. The variable
1352 and constant sizes must be combined, the size may have to be rounded,
1353 and there may be a minimum required size. */
1357 args_size->var = ARGS_SIZE_TREE (*args_size);
1358 args_size->constant = 0;
1360 #ifdef PREFERRED_STACK_BOUNDARY
1361 preferred_stack_boundary /= BITS_PER_UNIT;
1362 if (preferred_stack_boundary > 1)
1364 /* We don't handle this case yet. To handle it correctly we have
1365 to add the delta, round and substract the delta.
1366 Currently no machine description requires this support. */
1367 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1369 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1373 if (reg_parm_stack_space > 0)
1376 = size_binop (MAX_EXPR, args_size->var,
1377 ssize_int (reg_parm_stack_space));
1379 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1380 /* The area corresponding to register parameters is not to count in
1381 the size of the block we need. So make the adjustment. */
1383 = size_binop (MINUS_EXPR, args_size->var,
1384 ssize_int (reg_parm_stack_space));
1390 #ifdef PREFERRED_STACK_BOUNDARY
1391 preferred_stack_boundary /= BITS_PER_UNIT;
1392 if (preferred_stack_boundary < 1)
1393 preferred_stack_boundary = 1;
1394 args_size->constant = (((args_size->constant
1395 + stack_pointer_delta
1396 + preferred_stack_boundary - 1)
1397 / preferred_stack_boundary
1398 * preferred_stack_boundary)
1399 - stack_pointer_delta);
1402 args_size->constant = MAX (args_size->constant,
1403 reg_parm_stack_space);
1405 #ifdef MAYBE_REG_PARM_STACK_SPACE
1406 if (reg_parm_stack_space == 0)
1407 args_size->constant = 0;
1410 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1411 args_size->constant -= reg_parm_stack_space;
1414 return unadjusted_args_size;
1417 /* Precompute parameters as needed for a function call.
1419 FLAGS is mask of ECF_* constants.
1421 NUM_ACTUALS is the number of arguments.
1423 ARGS is an array containing information for each argument; this routine
1424 fills in the INITIAL_VALUE and VALUE fields for each precomputed argument.
1428 precompute_arguments (flags, num_actuals, args)
1431 struct arg_data *args;
1435 /* If this function call is cse'able, precompute all the parameters.
1436 Note that if the parameter is constructed into a temporary, this will
1437 cause an additional copy because the parameter will be constructed
1438 into a temporary location and then copied into the outgoing arguments.
1439 If a parameter contains a call to alloca and this function uses the
1440 stack, precompute the parameter. */
1442 /* If we preallocated the stack space, and some arguments must be passed
1443 on the stack, then we must precompute any parameter which contains a
1444 function call which will store arguments on the stack.
1445 Otherwise, evaluating the parameter may clobber previous parameters
1446 which have already been stored into the stack. (we have code to avoid
1447 such case by saving the ougoing stack arguments, but it results in
1450 for (i = 0; i < num_actuals; i++)
1451 if ((flags & (ECF_CONST | ECF_PURE))
1452 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1454 /* If this is an addressable type, we cannot pre-evaluate it. */
1455 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1461 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1463 preserve_temp_slots (args[i].value);
1466 /* ANSI doesn't require a sequence point here,
1467 but PCC has one, so this will avoid some problems. */
1470 args[i].initial_value = args[i].value
1471 = protect_from_queue (args[i].value, 0);
1473 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) != args[i].mode)
1476 = convert_modes (args[i].mode,
1477 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1478 args[i].value, args[i].unsignedp);
1479 #ifdef PROMOTE_FOR_CALL_ONLY
1480 /* CSE will replace this only if it contains args[i].value
1481 pseudo, so convert it down to the declared mode using
1483 if (GET_CODE (args[i].value) == REG
1484 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1486 args[i].initial_value
1487 = gen_rtx_SUBREG (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1489 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1490 SUBREG_PROMOTED_UNSIGNED_P (args[i].initial_value)
1491 = args[i].unsignedp;
1498 /* Given the current state of MUST_PREALLOCATE and information about
1499 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1500 compute and return the final value for MUST_PREALLOCATE. */
1503 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1504 int must_preallocate;
1506 struct arg_data *args;
1507 struct args_size *args_size;
1509 /* See if we have or want to preallocate stack space.
1511 If we would have to push a partially-in-regs parm
1512 before other stack parms, preallocate stack space instead.
1514 If the size of some parm is not a multiple of the required stack
1515 alignment, we must preallocate.
1517 If the total size of arguments that would otherwise create a copy in
1518 a temporary (such as a CALL) is more than half the total argument list
1519 size, preallocation is faster.
1521 Another reason to preallocate is if we have a machine (like the m88k)
1522 where stack alignment is required to be maintained between every
1523 pair of insns, not just when the call is made. However, we assume here
1524 that such machines either do not have push insns (and hence preallocation
1525 would occur anyway) or the problem is taken care of with
1528 if (! must_preallocate)
1530 int partial_seen = 0;
1531 int copy_to_evaluate_size = 0;
1534 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1536 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1538 else if (partial_seen && args[i].reg == 0)
1539 must_preallocate = 1;
1541 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1542 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1543 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1544 || TREE_CODE (args[i].tree_value) == COND_EXPR
1545 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1546 copy_to_evaluate_size
1547 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1550 if (copy_to_evaluate_size * 2 >= args_size->constant
1551 && args_size->constant > 0)
1552 must_preallocate = 1;
1554 return must_preallocate;
1557 /* If we preallocated stack space, compute the address of each argument
1558 and store it into the ARGS array.
1560 We need not ensure it is a valid memory address here; it will be
1561 validized when it is used.
1563 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1566 compute_argument_addresses (args, argblock, num_actuals)
1567 struct arg_data *args;
1573 rtx arg_reg = argblock;
1574 int i, arg_offset = 0;
1576 if (GET_CODE (argblock) == PLUS)
1577 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1579 for (i = 0; i < num_actuals; i++)
1581 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1582 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1585 /* Skip this parm if it will not be passed on the stack. */
1586 if (! args[i].pass_on_stack && args[i].reg != 0)
1589 if (GET_CODE (offset) == CONST_INT)
1590 addr = plus_constant (arg_reg, INTVAL (offset));
1592 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1594 addr = plus_constant (addr, arg_offset);
1595 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1598 AGGREGATE_TYPE_P (TREE_TYPE (args[i].tree_value)));
1600 if (GET_CODE (slot_offset) == CONST_INT)
1601 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1603 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1605 addr = plus_constant (addr, arg_offset);
1606 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1611 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1612 in a call instruction.
1614 FNDECL is the tree node for the target function. For an indirect call
1615 FNDECL will be NULL_TREE.
1617 EXP is the CALL_EXPR for this call. */
1620 rtx_for_function_call (fndecl, exp)
1626 /* Get the function to call, in the form of RTL. */
1629 /* If this is the first use of the function, see if we need to
1630 make an external definition for it. */
1631 if (! TREE_USED (fndecl))
1633 assemble_external (fndecl);
1634 TREE_USED (fndecl) = 1;
1637 /* Get a SYMBOL_REF rtx for the function address. */
1638 funexp = XEXP (DECL_RTL (fndecl), 0);
1641 /* Generate an rtx (probably a pseudo-register) for the address. */
1646 expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1647 pop_temp_slots (); /* FUNEXP can't be BLKmode */
1649 /* Check the function is executable. */
1650 if (current_function_check_memory_usage)
1652 #ifdef POINTERS_EXTEND_UNSIGNED
1653 /* It might be OK to convert funexp in place, but there's
1654 a lot going on between here and when it happens naturally
1655 that this seems safer. */
1656 funaddr = convert_memory_address (Pmode, funexp);
1658 emit_library_call (chkr_check_exec_libfunc, 1,
1667 /* Do the register loads required for any wholly-register parms or any
1668 parms which are passed both on the stack and in a register. Their
1669 expressions were already evaluated.
1671 Mark all register-parms as living through the call, putting these USE
1672 insns in the CALL_INSN_FUNCTION_USAGE field. */
1675 load_register_parameters (args, num_actuals, call_fusage)
1676 struct arg_data *args;
1682 #ifdef LOAD_ARGS_REVERSED
1683 for (i = num_actuals - 1; i >= 0; i--)
1685 for (i = 0; i < num_actuals; i++)
1688 rtx reg = args[i].reg;
1689 int partial = args[i].partial;
1694 /* Set to non-negative if must move a word at a time, even if just
1695 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1696 we just use a normal move insn. This value can be zero if the
1697 argument is a zero size structure with no fields. */
1698 nregs = (partial ? partial
1699 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1700 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1701 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1704 /* Handle calls that pass values in multiple non-contiguous
1705 locations. The Irix 6 ABI has examples of this. */
1707 if (GET_CODE (reg) == PARALLEL)
1708 emit_group_load (reg, args[i].value,
1709 int_size_in_bytes (TREE_TYPE (args[i].tree_value)),
1710 TYPE_ALIGN (TREE_TYPE (args[i].tree_value)));
1712 /* If simple case, just do move. If normal partial, store_one_arg
1713 has already loaded the register for us. In all other cases,
1714 load the register(s) from memory. */
1716 else if (nregs == -1)
1717 emit_move_insn (reg, args[i].value);
1719 /* If we have pre-computed the values to put in the registers in
1720 the case of non-aligned structures, copy them in now. */
1722 else if (args[i].n_aligned_regs != 0)
1723 for (j = 0; j < args[i].n_aligned_regs; j++)
1724 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1725 args[i].aligned_regs[j]);
1727 else if (partial == 0 || args[i].pass_on_stack)
1728 move_block_to_reg (REGNO (reg),
1729 validize_mem (args[i].value), nregs,
1732 /* Handle calls that pass values in multiple non-contiguous
1733 locations. The Irix 6 ABI has examples of this. */
1734 if (GET_CODE (reg) == PARALLEL)
1735 use_group_regs (call_fusage, reg);
1736 else if (nregs == -1)
1737 use_reg (call_fusage, reg);
1739 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1744 /* Try to integreate function. See expand_inline_function for documentation
1745 about the parameters. */
1748 try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1754 rtx structure_value_addr;
1759 rtx old_stack_level = 0;
1760 int reg_parm_stack_space = 0;
1762 #ifdef REG_PARM_STACK_SPACE
1763 #ifdef MAYBE_REG_PARM_STACK_SPACE
1764 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1766 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1770 before_call = get_last_insn ();
1772 temp = expand_inline_function (fndecl, actparms, target,
1774 structure_value_addr);
1776 /* If inlining succeeded, return. */
1777 if (temp != (rtx) (HOST_WIDE_INT) - 1)
1779 if (ACCUMULATE_OUTGOING_ARGS)
1781 /* If the outgoing argument list must be preserved, push
1782 the stack before executing the inlined function if it
1785 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1786 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1789 if (stack_arg_under_construction || i >= 0)
1792 = before_call ? NEXT_INSN (before_call) : get_insns ();
1793 rtx insn = NULL_RTX, seq;
1795 /* Look for a call in the inline function code.
1796 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1797 nonzero then there is a call and it is not necessary
1798 to scan the insns. */
1800 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1801 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1802 if (GET_CODE (insn) == CALL_INSN)
1807 /* Reserve enough stack space so that the largest
1808 argument list of any function call in the inline
1809 function does not overlap the argument list being
1810 evaluated. This is usually an overestimate because
1811 allocate_dynamic_stack_space reserves space for an
1812 outgoing argument list in addition to the requested
1813 space, but there is no way to ask for stack space such
1814 that an argument list of a certain length can be
1817 Add the stack space reserved for register arguments, if
1818 any, in the inline function. What is really needed is the
1819 largest value of reg_parm_stack_space in the inline
1820 function, but that is not available. Using the current
1821 value of reg_parm_stack_space is wrong, but gives
1822 correct results on all supported machines. */
1824 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1825 + reg_parm_stack_space);
1828 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1829 allocate_dynamic_stack_space (GEN_INT (adjust),
1830 NULL_RTX, BITS_PER_UNIT);
1833 emit_insns_before (seq, first_insn);
1834 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1839 /* If the result is equivalent to TARGET, return TARGET to simplify
1840 checks in store_expr. They can be equivalent but not equal in the
1841 case of a function that returns BLKmode. */
1842 if (temp != target && rtx_equal_p (temp, target))
1847 /* If inlining failed, mark FNDECL as needing to be compiled
1848 separately after all. If function was declared inline,
1850 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1851 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1853 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1854 warning ("called from here");
1856 mark_addressable (fndecl);
1857 return (rtx) (HOST_WIDE_INT) - 1;
1860 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1861 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1862 bytes, then we would need to push some additional bytes to pad the
1863 arguments. So, we adjust the stack pointer by an amount that will
1864 leave the stack under-aligned by UNADJUSTED_ARGS_SIZE bytes. Then,
1865 when the arguments are pushed the stack will be perfectly aligned.
1866 ARGS_SIZE->CONSTANT is set to the number of bytes that should be
1867 popped after the call. */
1870 combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1872 preferred_unit_stack_boundary)
1873 int unadjusted_args_size;
1874 struct args_size *args_size;
1875 int preferred_unit_stack_boundary;
1877 /* The number of bytes to pop so that the stack will be
1878 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1879 HOST_WIDE_INT adjustment;
1880 /* The alignment of the stack after the arguments are pushed, if we
1881 just pushed the arguments without adjust the stack here. */
1882 HOST_WIDE_INT unadjusted_alignment;
1884 unadjusted_alignment
1885 = ((stack_pointer_delta + unadjusted_args_size)
1886 % preferred_unit_stack_boundary);
1888 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1889 as possible -- leaving just enough left to cancel out the
1890 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1891 PENDING_STACK_ADJUST is non-negative, and congruent to
1892 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1894 /* Begin by trying to pop all the bytes. */
1895 unadjusted_alignment
1896 = (unadjusted_alignment
1897 - (pending_stack_adjust % preferred_unit_stack_boundary));
1898 adjustment = pending_stack_adjust;
1899 /* Push enough additional bytes that the stack will be aligned
1900 after the arguments are pushed. */
1901 if (unadjusted_alignment >= 0)
1902 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1904 adjustment += unadjusted_alignment;
1906 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1907 bytes after the call. The right number is the entire
1908 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1909 by the arguments in the first place. */
1911 = pending_stack_adjust - adjustment + unadjusted_args_size;
1913 /* Push the right number of bytes. */
1914 pending_stack_adjust = adjustment;
1915 do_pending_stack_adjust ();
1918 /* Generate all the code for a function call
1919 and return an rtx for its value.
1920 Store the value in TARGET (specified as an rtx) if convenient.
1921 If the value is stored in TARGET then TARGET is returned.
1922 If IGNORE is nonzero, then we ignore the value of the function call. */
1925 expand_call (exp, target, ignore)
1930 /* Nonzero if we are currently expanding a call. */
1931 static int currently_expanding_call = 0;
1933 /* List of actual parameters. */
1934 tree actparms = TREE_OPERAND (exp, 1);
1935 /* RTX for the function to be called. */
1937 /* Sequence of insns to perform a tail recursive "call". */
1938 rtx tail_recursion_insns = NULL_RTX;
1939 /* Sequence of insns to perform a normal "call". */
1940 rtx normal_call_insns = NULL_RTX;
1941 /* Sequence of insns to perform a tail recursive "call". */
1942 rtx tail_call_insns = NULL_RTX;
1943 /* Data type of the function. */
1945 /* Declaration of the function being called,
1946 or 0 if the function is computed (not known by name). */
1953 /* Register in which non-BLKmode value will be returned,
1954 or 0 if no value or if value is BLKmode. */
1956 /* Address where we should return a BLKmode value;
1957 0 if value not BLKmode. */
1958 rtx structure_value_addr = 0;
1959 /* Nonzero if that address is being passed by treating it as
1960 an extra, implicit first parameter. Otherwise,
1961 it is passed by being copied directly into struct_value_rtx. */
1962 int structure_value_addr_parm = 0;
1963 /* Size of aggregate value wanted, or zero if none wanted
1964 or if we are using the non-reentrant PCC calling convention
1965 or expecting the value in registers. */
1966 HOST_WIDE_INT struct_value_size = 0;
1967 /* Nonzero if called function returns an aggregate in memory PCC style,
1968 by returning the address of where to find it. */
1969 int pcc_struct_value = 0;
1971 /* Number of actual parameters in this call, including struct value addr. */
1973 /* Number of named args. Args after this are anonymous ones
1974 and they must all go on the stack. */
1977 /* Vector of information about each argument.
1978 Arguments are numbered in the order they will be pushed,
1979 not the order they are written. */
1980 struct arg_data *args;
1982 /* Total size in bytes of all the stack-parms scanned so far. */
1983 struct args_size args_size;
1984 /* Size of arguments before any adjustments (such as rounding). */
1985 int unadjusted_args_size;
1986 /* Data on reg parms scanned so far. */
1987 CUMULATIVE_ARGS args_so_far;
1988 /* Nonzero if a reg parm has been scanned. */
1990 /* Nonzero if this is an indirect function call. */
1992 /* Nonzero if we must avoid push-insns in the args for this call.
1993 If stack space is allocated for register parameters, but not by the
1994 caller, then it is preallocated in the fixed part of the stack frame.
1995 So the entire argument block must then be preallocated (i.e., we
1996 ignore PUSH_ROUNDING in that case). */
1998 int must_preallocate = !PUSH_ARGS;
2000 /* Size of the stack reserved for parameter registers. */
2001 int reg_parm_stack_space = 0;
2003 /* Address of space preallocated for stack parms
2004 (on machines that lack push insns), or 0 if space not preallocated. */
2007 /* Mask of ECF_ flags. */
2009 /* Nonzero if this is a call to an inline function. */
2010 int is_integrable = 0;
2011 #ifdef REG_PARM_STACK_SPACE
2012 /* Define the boundary of the register parm stack space that needs to be
2014 int low_to_save = -1, high_to_save;
2015 rtx save_area = 0; /* Place that it is saved */
2018 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2019 char *initial_stack_usage_map = stack_usage_map;
2020 int old_stack_arg_under_construction = 0;
2022 rtx old_stack_level = 0;
2023 int old_pending_adj = 0;
2024 int old_inhibit_defer_pop = inhibit_defer_pop;
2025 int old_stack_allocated;
2029 /* The alignment of the stack, in bits. */
2030 HOST_WIDE_INT preferred_stack_boundary;
2031 /* The alignment of the stack, in bytes. */
2032 HOST_WIDE_INT preferred_unit_stack_boundary;
2034 /* The value of the function call can be put in a hard register. But
2035 if -fcheck-memory-usage, code which invokes functions (and thus
2036 damages some hard registers) can be inserted before using the value.
2037 So, target is always a pseudo-register in that case. */
2038 if (current_function_check_memory_usage)
2041 /* See if this is "nothrow" function call. */
2042 if (TREE_NOTHROW (exp))
2043 flags |= ECF_NOTHROW;
2045 /* See if we can find a DECL-node for the actual function.
2046 As a result, decide whether this is a call to an integrable function. */
2048 fndecl = get_callee_fndecl (exp);
2052 && fndecl != current_function_decl
2053 && DECL_INLINE (fndecl)
2054 && DECL_SAVED_INSNS (fndecl)
2055 && DECL_SAVED_INSNS (fndecl)->inlinable)
2057 else if (! TREE_ADDRESSABLE (fndecl))
2059 /* In case this function later becomes inlinable,
2060 record that there was already a non-inline call to it.
2062 Use abstraction instead of setting TREE_ADDRESSABLE
2064 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2067 warning_with_decl (fndecl, "can't inline call to `%s'");
2068 warning ("called from here");
2070 mark_addressable (fndecl);
2073 flags |= flags_from_decl_or_type (fndecl);
2076 /* If we don't have specific function to call, see if we have a
2077 attributes set in the type. */
2080 p = TREE_OPERAND (exp, 0);
2081 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2084 #ifdef REG_PARM_STACK_SPACE
2085 #ifdef MAYBE_REG_PARM_STACK_SPACE
2086 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2088 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2092 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2093 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2094 must_preallocate = 1;
2097 /* Warn if this value is an aggregate type,
2098 regardless of which calling convention we are using for it. */
2099 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2100 warning ("function call has aggregate value");
2102 /* Set up a place to return a structure. */
2104 /* Cater to broken compilers. */
2105 if (aggregate_value_p (exp))
2107 /* This call returns a big structure. */
2108 flags &= ~(ECF_CONST | ECF_PURE);
2110 #ifdef PCC_STATIC_STRUCT_RETURN
2112 pcc_struct_value = 1;
2113 /* Easier than making that case work right. */
2116 /* In case this is a static function, note that it has been
2118 if (! TREE_ADDRESSABLE (fndecl))
2119 mark_addressable (fndecl);
2123 #else /* not PCC_STATIC_STRUCT_RETURN */
2125 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2127 if (target && GET_CODE (target) == MEM)
2128 structure_value_addr = XEXP (target, 0);
2131 /* Assign a temporary to hold the value. */
2134 /* For variable-sized objects, we must be called with a target
2135 specified. If we were to allocate space on the stack here,
2136 we would have no way of knowing when to free it. */
2138 if (struct_value_size < 0)
2141 /* This DECL is just something to feed to mark_addressable;
2142 it doesn't get pushed. */
2143 d = build_decl (VAR_DECL, NULL_TREE, TREE_TYPE (exp));
2144 DECL_RTL (d) = assign_temp (TREE_TYPE (exp), 1, 0, 1);
2145 mark_addressable (d);
2146 mark_temp_addr_taken (DECL_RTL (d));
2147 structure_value_addr = XEXP (DECL_RTL (d), 0);
2152 #endif /* not PCC_STATIC_STRUCT_RETURN */
2155 /* If called function is inline, try to integrate it. */
2159 rtx temp = try_to_integrate (fndecl, actparms, target,
2160 ignore, TREE_TYPE (exp),
2161 structure_value_addr);
2162 if (temp != (rtx) (HOST_WIDE_INT) - 1)
2166 currently_expanding_call++;
2168 /* Tail calls can make things harder to debug, and we're traditionally
2169 pushed these optimizations into -O2. Don't try if we're already
2170 expanding a call, as that means we're an argument. Similarly, if
2171 there's pending loops or cleanups we know there's code to follow
2174 If rtx_equal_function_value_matters is false, that means we've
2175 finished with regular parsing. Which means that some of the
2176 machinery we use to generate tail-calls is no longer in place.
2177 This is most often true of sjlj-exceptions, which we couldn't
2178 tail-call to anyway. */
2181 if (flag_optimize_sibling_calls
2182 && currently_expanding_call == 1
2183 && rtx_equal_function_value_matters
2184 && stmt_loop_nest_empty ()
2185 && ! any_pending_cleanups (1))
2187 tree new_actparms = NULL_TREE;
2189 /* Ok, we're going to give the tail call the old college try.
2190 This means we're going to evaluate the function arguments
2191 up to three times. There are two degrees of badness we can
2192 encounter, those that can be unsaved and those that can't.
2193 (See unsafe_for_reeval commentary for details.)
2195 Generate a new argument list. Pass safe arguments through
2196 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2197 For hard badness, evaluate them now and put their resulting
2198 rtx in a temporary VAR_DECL. */
2200 for (p = actparms; p; p = TREE_CHAIN (p))
2201 switch (unsafe_for_reeval (TREE_VALUE (p)))
2204 new_actparms = tree_cons (TREE_PURPOSE (p), TREE_VALUE (p),
2208 case 1: /* Mildly unsafe. */
2209 new_actparms = tree_cons (TREE_PURPOSE (p),
2210 unsave_expr (TREE_VALUE (p)),
2214 case 2: /* Wildly unsafe. */
2216 tree var = build_decl (VAR_DECL, NULL_TREE,
2217 TREE_TYPE (TREE_VALUE (p)));
2218 DECL_RTL (var) = expand_expr (TREE_VALUE (p), NULL_RTX,
2219 VOIDmode, EXPAND_NORMAL);
2220 new_actparms = tree_cons (TREE_PURPOSE (p), var, new_actparms);
2228 /* We built the new argument chain backwards. */
2229 actparms = nreverse (new_actparms);
2231 /* Expanding one of those dangerous arguments could have added
2232 cleanups, but otherwise give it a whirl. */
2233 try_tail_call = ! any_pending_cleanups (1);
2236 /* Generate a tail recursion sequence when calling ourselves. */
2239 && TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
2240 && TREE_OPERAND (TREE_OPERAND (exp, 0), 0) == current_function_decl)
2242 /* We want to emit any pending stack adjustments before the tail
2243 recursion "call". That way we know any adjustment after the tail
2244 recursion call can be ignored if we indeed use the tail recursion
2246 int save_pending_stack_adjust = pending_stack_adjust;
2247 int save_stack_pointer_delta = stack_pointer_delta;
2249 /* Use a new sequence to hold any RTL we generate. We do not even
2250 know if we will use this RTL yet. The final decision can not be
2251 made until after RTL generation for the entire function is
2255 /* Emit the pending stack adjustments before we expand any arguments. */
2256 do_pending_stack_adjust ();
2258 if (optimize_tail_recursion (actparms, get_last_insn ()))
2259 tail_recursion_insns = get_insns ();
2262 /* Restore the original pending stack adjustment for the sibling and
2263 normal call cases below. */
2264 pending_stack_adjust = save_pending_stack_adjust;
2265 stack_pointer_delta = save_stack_pointer_delta;
2268 function_call_count++;
2270 if (fndecl && DECL_NAME (fndecl))
2271 name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
2273 /* Figure out the amount to which the stack should be aligned. */
2274 #ifdef PREFERRED_STACK_BOUNDARY
2275 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2277 preferred_stack_boundary = STACK_BOUNDARY;
2279 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2281 /* Ensure current function's preferred stack boundary is at least
2282 what we need. We don't have to increase alignment for recursive
2284 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2285 && fndecl != current_function_decl)
2286 cfun->preferred_stack_boundary = preferred_stack_boundary;
2288 /* See if this is a call to a function that can return more than once
2289 or a call to longjmp or malloc. */
2290 flags |= special_function_p (fndecl, flags);
2292 if (flags & ECF_MAY_BE_ALLOCA)
2293 current_function_calls_alloca = 1;
2295 /* Operand 0 is a pointer-to-function; get the type of the function. */
2296 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
2297 if (! POINTER_TYPE_P (funtype))
2299 funtype = TREE_TYPE (funtype);
2301 /* We want to make two insn chains; one for a sibling call, the other
2302 for a normal call. We will select one of the two chains after
2303 initial RTL generation is complete. */
2304 for (pass = 0; pass < 2; pass++)
2306 int sibcall_failure = 0;
2307 /* We want to emit ay pending stack adjustments before the tail
2308 recursion "call". That way we know any adjustment after the tail
2309 recursion call can be ignored if we indeed use the tail recursion
2311 int save_pending_stack_adjust;
2312 int save_stack_pointer_delta;
2314 rtx before_call, next_arg_reg;
2318 /* Various reasons we can not use a sibling call. */
2320 #ifdef HAVE_sibcall_epilogue
2321 || ! HAVE_sibcall_epilogue
2325 /* The structure value address is used and modified in the
2326 loop below. It does not seem worth the effort to save and
2327 restore it as a state variable since few optimizable
2328 sibling calls will return a structure. */
2329 || structure_value_addr != NULL_RTX
2330 /* If the register holding the address is a callee saved
2331 register, then we lose. We have no way to prevent that,
2332 so we only allow calls to named functions. */
2333 /* ??? This could be done by having the insn constraints
2334 use a register class that is all call-clobbered. Any
2335 reload insns generated to fix things up would appear
2336 before the sibcall_epilogue. */
2337 || fndecl == NULL_TREE
2338 || ! FUNCTION_OK_FOR_SIBCALL (fndecl))
2341 /* Emit any queued insns now; otherwise they would end up in
2342 only one of the alternates. */
2345 /* We know at this point that there are not currently any
2346 pending cleanups. If, however, in the process of evaluating
2347 the arguments we were to create some, we'll need to be
2348 able to get rid of them. */
2349 expand_start_target_temps ();
2351 /* State variables we need to save and restore between
2353 save_pending_stack_adjust = pending_stack_adjust;
2354 save_stack_pointer_delta = stack_pointer_delta;
2357 flags &= ~ECF_SIBCALL;
2359 flags |= ECF_SIBCALL;
2361 /* Other state variables that we must reinitialize each time
2362 through the loop (that are not initialized by the loop itself). */
2366 /* Start a new sequence for the normal call case.
2368 From this point on, if the sibling call fails, we want to set
2369 sibcall_failure instead of continuing the loop. */
2372 /* When calling a const function, we must pop the stack args right away,
2373 so that the pop is deleted or moved with the call. */
2374 if (flags & (ECF_CONST | ECF_PURE))
2377 /* Don't let pending stack adjusts add up to too much.
2378 Also, do all pending adjustments now if there is any chance
2379 this might be a call to alloca or if we are expanding a sibling
2381 if (pending_stack_adjust >= 32
2382 || (pending_stack_adjust > 0 && (flags & ECF_MAY_BE_ALLOCA))
2384 do_pending_stack_adjust ();
2386 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2388 /* A fork duplicates the profile information, and an exec discards
2389 it. We can't rely on fork/exec to be paired. So write out the
2390 profile information we have gathered so far, and clear it. */
2391 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2392 is subject to race conditions, just as with multithreaded
2395 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__bb_fork_func"), 0,
2399 /* Push the temporary stack slot level so that we can free any
2400 temporaries we make. */
2403 /* Start updating where the next arg would go.
2405 On some machines (such as the PA) indirect calls have a different
2406 calling convention than normal calls. The last argument in
2407 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2409 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
2411 /* If struct_value_rtx is 0, it means pass the address
2412 as if it were an extra parameter. */
2413 if (structure_value_addr && struct_value_rtx == 0)
2415 /* If structure_value_addr is a REG other than
2416 virtual_outgoing_args_rtx, we can use always use it. If it
2417 is not a REG, we must always copy it into a register.
2418 If it is virtual_outgoing_args_rtx, we must copy it to another
2419 register in some cases. */
2420 rtx temp = (GET_CODE (structure_value_addr) != REG
2421 || (ACCUMULATE_OUTGOING_ARGS
2422 && stack_arg_under_construction
2423 && structure_value_addr == virtual_outgoing_args_rtx)
2424 ? copy_addr_to_reg (structure_value_addr)
2425 : structure_value_addr);
2428 = tree_cons (error_mark_node,
2429 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2432 structure_value_addr_parm = 1;
2435 /* Count the arguments and set NUM_ACTUALS. */
2436 for (p = actparms, i = 0; p; p = TREE_CHAIN (p)) i++;
2439 /* Compute number of named args.
2440 Normally, don't include the last named arg if anonymous args follow.
2441 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2442 (If no anonymous args follow, the result of list_length is actually
2443 one too large. This is harmless.)
2445 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2446 zero, this machine will be able to place unnamed args that were
2447 passed in registers into the stack. So treat all args as named.
2448 This allows the insns emitting for a specific argument list to be
2449 independent of the function declaration.
2451 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2452 reliable way to pass unnamed args in registers, so we must force
2453 them into memory. */
2455 if ((STRICT_ARGUMENT_NAMING
2456 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2457 && TYPE_ARG_TYPES (funtype) != 0)
2459 = (list_length (TYPE_ARG_TYPES (funtype))
2460 /* Don't include the last named arg. */
2461 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2462 /* Count the struct value address, if it is passed as a parm. */
2463 + structure_value_addr_parm);
2465 /* If we know nothing, treat all args as named. */
2466 n_named_args = num_actuals;
2468 /* Make a vector to hold all the information about each arg. */
2469 args = (struct arg_data *) alloca (num_actuals
2470 * sizeof (struct arg_data));
2471 bzero ((char *) args, num_actuals * sizeof (struct arg_data));
2473 /* Build up entries inthe ARGS array, compute the size of the arguments
2474 into ARGS_SIZE, etc. */
2475 initialize_argument_information (num_actuals, args, &args_size,
2476 n_named_args, actparms, fndecl,
2477 &args_so_far, reg_parm_stack_space,
2478 &old_stack_level, &old_pending_adj,
2479 &must_preallocate, &flags);
2481 #ifdef FINAL_REG_PARM_STACK_SPACE
2482 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2488 /* If this function requires a variable-sized argument list, don't
2489 try to make a cse'able block for this call. We may be able to
2490 do this eventually, but it is too complicated to keep track of
2491 what insns go in the cse'able block and which don't.
2493 Also do not make a sibling call. */
2495 flags &= ~(ECF_CONST | ECF_PURE);
2496 must_preallocate = 1;
2497 sibcall_failure = 1;
2500 if (args_size.constant > current_function_args_size)
2502 /* If this function requires more stack slots than the current
2503 function, we cannot change it into a sibling call. */
2504 sibcall_failure = 1;
2507 /* Compute the actual size of the argument block required. The variable
2508 and constant sizes must be combined, the size may have to be rounded,
2509 and there may be a minimum required size. When generating a sibcall
2510 pattern, do not round up, since we'll be re-using whatever space our
2512 unadjusted_args_size
2513 = compute_argument_block_size (reg_parm_stack_space, &args_size,
2515 : preferred_stack_boundary));
2517 /* If the callee pops its own arguments, then it must pop exactly
2518 the same number of arguments as the current function. */
2519 if (RETURN_POPS_ARGS (fndecl, funtype, unadjusted_args_size)
2520 != RETURN_POPS_ARGS (current_function_decl,
2521 TREE_TYPE (current_function_decl),
2522 current_function_args_size))
2523 sibcall_failure = 1;
2525 /* Now make final decision about preallocating stack space. */
2526 must_preallocate = finalize_must_preallocate (must_preallocate,
2530 /* If the structure value address will reference the stack pointer, we
2531 must stabilize it. We don't need to do this if we know that we are
2532 not going to adjust the stack pointer in processing this call. */
2534 if (structure_value_addr
2535 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2536 || reg_mentioned_p (virtual_outgoing_args_rtx,
2537 structure_value_addr))
2539 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2540 structure_value_addr = copy_to_reg (structure_value_addr);
2542 /* Precompute any arguments as needed. */
2544 precompute_arguments (flags, num_actuals, args);
2546 /* Now we are about to start emitting insns that can be deleted
2547 if a libcall is deleted. */
2548 if (flags & (ECF_CONST | ECF_PURE | ECF_MALLOC))
2551 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2552 /* The argument block when performing a sibling call is the
2553 incoming argument block. */
2555 argblock = virtual_incoming_args_rtx;
2556 /* If we have no actual push instructions, or shouldn't use them,
2557 make space for all args right now. */
2559 else if (args_size.var != 0)
2561 if (old_stack_level == 0)
2563 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2564 old_pending_adj = pending_stack_adjust;
2565 pending_stack_adjust = 0;
2566 /* stack_arg_under_construction says whether a stack arg is
2567 being constructed at the old stack level. Pushing the stack
2568 gets a clean outgoing argument block. */
2569 old_stack_arg_under_construction = stack_arg_under_construction;
2570 stack_arg_under_construction = 0;
2572 argblock = push_block (ARGS_SIZE_RTX (args_size), 0, 0);
2576 /* Note that we must go through the motions of allocating an argument
2577 block even if the size is zero because we may be storing args
2578 in the area reserved for register arguments, which may be part of
2581 int needed = args_size.constant;
2583 /* Store the maximum argument space used. It will be pushed by
2584 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2587 if (needed > current_function_outgoing_args_size)
2588 current_function_outgoing_args_size = needed;
2590 if (must_preallocate)
2592 if (ACCUMULATE_OUTGOING_ARGS)
2594 /* Since the stack pointer will never be pushed, it is
2595 possible for the evaluation of a parm to clobber
2596 something we have already written to the stack.
2597 Since most function calls on RISC machines do not use
2598 the stack, this is uncommon, but must work correctly.
2600 Therefore, we save any area of the stack that was already
2601 written and that we are using. Here we set up to do this
2602 by making a new stack usage map from the old one. The
2603 actual save will be done by store_one_arg.
2605 Another approach might be to try to reorder the argument
2606 evaluations to avoid this conflicting stack usage. */
2608 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2609 /* Since we will be writing into the entire argument area,
2610 the map must be allocated for its entire size, not just
2611 the part that is the responsibility of the caller. */
2612 needed += reg_parm_stack_space;
2615 #ifdef ARGS_GROW_DOWNWARD
2616 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2619 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2623 = (char *) alloca (highest_outgoing_arg_in_use);
2625 if (initial_highest_arg_in_use)
2626 bcopy (initial_stack_usage_map, stack_usage_map,
2627 initial_highest_arg_in_use);
2629 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2630 bzero (&stack_usage_map[initial_highest_arg_in_use],
2631 (highest_outgoing_arg_in_use
2632 - initial_highest_arg_in_use));
2635 /* The address of the outgoing argument list must not be
2636 copied to a register here, because argblock would be left
2637 pointing to the wrong place after the call to
2638 allocate_dynamic_stack_space below. */
2640 argblock = virtual_outgoing_args_rtx;
2644 if (inhibit_defer_pop == 0)
2646 /* Try to reuse some or all of the pending_stack_adjust
2647 to get this space. Maybe we can avoid any pushing. */
2648 if (needed > pending_stack_adjust)
2650 needed -= pending_stack_adjust;
2651 pending_stack_adjust = 0;
2655 pending_stack_adjust -= needed;
2659 /* Special case this because overhead of `push_block' in this
2660 case is non-trivial. */
2662 argblock = virtual_outgoing_args_rtx;
2664 argblock = push_block (GEN_INT (needed), 0, 0);
2666 /* We only really need to call `copy_to_reg' in the case
2667 where push insns are going to be used to pass ARGBLOCK
2668 to a function call in ARGS. In that case, the stack
2669 pointer changes value from the allocation point to the
2670 call point, and hence the value of
2671 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2672 as well always do it. */
2673 argblock = copy_to_reg (argblock);
2675 /* The save/restore code in store_one_arg handles all
2677 a constructor call (including a C function returning
2678 a BLKmode struct) to initialize an argument. */
2679 if (stack_arg_under_construction)
2681 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2682 rtx push_size = GEN_INT (reg_parm_stack_space + args_size.constant);
2684 rtx push_size = GEN_INT (args_size.constant);
2686 if (old_stack_level == 0)
2688 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2689 old_pending_adj = pending_stack_adjust;
2690 pending_stack_adjust = 0;
2691 /* stack_arg_under_construction says whether a stack arg is
2692 being constructed at the old stack level. Pushing the stack
2693 gets a clean outgoing argument block. */
2694 old_stack_arg_under_construction = stack_arg_under_construction;
2695 stack_arg_under_construction = 0;
2696 /* Make a new map for the new argument list. */
2697 stack_usage_map = (char *)alloca (highest_outgoing_arg_in_use);
2698 bzero (stack_usage_map, highest_outgoing_arg_in_use);
2699 highest_outgoing_arg_in_use = 0;
2701 allocate_dynamic_stack_space (push_size, NULL_RTX, BITS_PER_UNIT);
2703 /* If argument evaluation might modify the stack pointer, copy the
2704 address of the argument list to a register. */
2705 for (i = 0; i < num_actuals; i++)
2706 if (args[i].pass_on_stack)
2708 argblock = copy_addr_to_reg (argblock);
2715 compute_argument_addresses (args, argblock, num_actuals);
2717 #ifdef PREFERRED_STACK_BOUNDARY
2718 /* If we push args individually in reverse order, perform stack alignment
2719 before the first push (the last arg). */
2720 if (PUSH_ARGS_REVERSED && argblock == 0
2721 && args_size.constant != unadjusted_args_size)
2723 /* When the stack adjustment is pending, we get better code
2724 by combining the adjustments. */
2725 if (pending_stack_adjust
2726 && ! (flags & (ECF_CONST | ECF_PURE))
2727 && ! inhibit_defer_pop)
2728 combine_pending_stack_adjustment_and_call
2729 (unadjusted_args_size,
2731 preferred_unit_stack_boundary);
2732 else if (argblock == 0)
2733 anti_adjust_stack (GEN_INT (args_size.constant
2734 - unadjusted_args_size));
2736 /* Now that the stack is properly aligned, pops can't safely
2737 be deferred during the evaluation of the arguments. */
2741 /* Don't try to defer pops if preallocating, not even from the first arg,
2742 since ARGBLOCK probably refers to the SP. */
2746 funexp = rtx_for_function_call (fndecl, exp);
2748 /* Figure out the register where the value, if any, will come back. */
2750 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2751 && ! structure_value_addr)
2753 if (pcc_struct_value)
2754 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2755 fndecl, (pass == 0));
2757 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2760 /* Precompute all register parameters. It isn't safe to compute anything
2761 once we have started filling any specific hard regs. */
2762 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2764 #ifdef REG_PARM_STACK_SPACE
2765 /* Save the fixed argument area if it's part of the caller's frame and
2766 is clobbered by argument setup for this call. */
2767 if (ACCUMULATE_OUTGOING_ARGS && pass)
2768 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2769 &low_to_save, &high_to_save);
2772 /* Now store (and compute if necessary) all non-register parms.
2773 These come before register parms, since they can require block-moves,
2774 which could clobber the registers used for register parms.
2775 Parms which have partial registers are not stored here,
2776 but we do preallocate space here if they want that. */
2778 for (i = 0; i < num_actuals; i++)
2779 if (args[i].reg == 0 || args[i].pass_on_stack)
2780 store_one_arg (&args[i], argblock, flags,
2781 args_size.var != 0, reg_parm_stack_space);
2783 /* If we have a parm that is passed in registers but not in memory
2784 and whose alignment does not permit a direct copy into registers,
2785 make a group of pseudos that correspond to each register that we
2787 if (STRICT_ALIGNMENT)
2788 store_unaligned_arguments_into_pseudos (args, num_actuals);
2790 /* Now store any partially-in-registers parm.
2791 This is the last place a block-move can happen. */
2793 for (i = 0; i < num_actuals; i++)
2794 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2795 store_one_arg (&args[i], argblock, flags,
2796 args_size.var != 0, reg_parm_stack_space);
2798 #ifdef PREFERRED_STACK_BOUNDARY
2799 /* If we pushed args in forward order, perform stack alignment
2800 after pushing the last arg. */
2801 if (!PUSH_ARGS_REVERSED && argblock == 0)
2802 anti_adjust_stack (GEN_INT (args_size.constant
2803 - unadjusted_args_size));
2806 /* If register arguments require space on the stack and stack space
2807 was not preallocated, allocate stack space here for arguments
2808 passed in registers. */
2809 #ifdef OUTGOING_REG_PARM_STACK_SPACE
2810 if (!ACCUMULATE_OUTGOING_ARGS
2811 && must_preallocate == 0 && reg_parm_stack_space > 0)
2812 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
2815 /* Pass the function the address in which to return a
2817 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
2819 emit_move_insn (struct_value_rtx,
2821 force_operand (structure_value_addr,
2824 /* Mark the memory for the aggregate as write-only. */
2825 if (current_function_check_memory_usage)
2826 emit_library_call (chkr_set_right_libfunc, 1,
2828 structure_value_addr, ptr_mode,
2829 GEN_INT (struct_value_size),
2830 TYPE_MODE (sizetype),
2831 GEN_INT (MEMORY_USE_WO),
2832 TYPE_MODE (integer_type_node));
2834 if (GET_CODE (struct_value_rtx) == REG)
2835 use_reg (&call_fusage, struct_value_rtx);
2838 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
2841 load_register_parameters (args, num_actuals, &call_fusage);
2843 /* Perform postincrements before actually calling the function. */
2846 /* Save a pointer to the last insn before the call, so that we can
2847 later safely search backwards to find the CALL_INSN. */
2848 before_call = get_last_insn ();
2850 /* Set up next argument register. For sibling calls on machines
2851 with register windows this should be the incoming register. */
2852 #ifdef FUNCTION_INCOMING_ARG
2854 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
2858 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
2861 /* All arguments and registers used for the call must be set up by
2864 #ifdef PREFERRED_STACK_BOUNDARY
2865 /* Stack must to be properly aligned now. */
2866 if (stack_pointer_delta & (preferred_stack_boundary / BITS_PER_UNIT - 1))
2870 /* Generate the actual call instruction. */
2871 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
2872 args_size.constant, struct_value_size,
2873 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
2876 /* Verify that we've deallocated all the stack we used. */
2878 && old_stack_allocated != stack_pointer_delta - pending_stack_adjust)
2881 /* If call is cse'able, make appropriate pair of reg-notes around it.
2882 Test valreg so we don't crash; may safely ignore `const'
2883 if return type is void. Disable for PARALLEL return values, because
2884 we have no way to move such values into a pseudo register. */
2885 if ((flags & (ECF_CONST | ECF_PURE))
2886 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
2889 rtx temp = gen_reg_rtx (GET_MODE (valreg));
2892 /* Mark the return value as a pointer if needed. */
2893 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
2894 mark_reg_pointer (temp, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
2896 /* Construct an "equal form" for the value which mentions all the
2897 arguments in order as well as the function name. */
2898 for (i = 0; i < num_actuals; i++)
2899 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
2900 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
2902 insns = get_insns ();
2905 if (flags & ECF_PURE)
2906 note = gen_rtx_EXPR_LIST (VOIDmode,
2907 gen_rtx_USE (VOIDmode,
2908 gen_rtx_MEM (BLKmode,
2909 gen_rtx_SCRATCH (VOIDmode))), note);
2911 emit_libcall_block (insns, temp, valreg, note);
2915 else if (flags & (ECF_CONST | ECF_PURE))
2917 /* Otherwise, just write out the sequence without a note. */
2918 rtx insns = get_insns ();
2923 else if (flags & ECF_MALLOC)
2925 rtx temp = gen_reg_rtx (GET_MODE (valreg));
2928 /* The return value from a malloc-like function is a pointer. */
2929 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
2930 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
2932 emit_move_insn (temp, valreg);
2934 /* The return value from a malloc-like function can not alias
2936 last = get_last_insn ();
2938 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
2940 /* Write out the sequence. */
2941 insns = get_insns ();
2947 /* For calls to `setjmp', etc., inform flow.c it should complain
2948 if nonvolatile values are live. For functions that cannot return,
2949 inform flow that control does not fall through. */
2951 if ((flags & (ECF_RETURNS_TWICE | ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
2953 /* The barrier or NOTE_INSN_SETJMP note must be emitted
2954 immediately after the CALL_INSN. Some ports emit more
2955 than just a CALL_INSN above, so we must search for it here. */
2957 rtx last = get_last_insn ();
2958 while (GET_CODE (last) != CALL_INSN)
2960 last = PREV_INSN (last);
2961 /* There was no CALL_INSN? */
2962 if (last == before_call)
2966 if (flags & ECF_RETURNS_TWICE)
2968 emit_note_after (NOTE_INSN_SETJMP, last);
2969 current_function_calls_setjmp = 1;
2970 sibcall_failure = 1;
2973 emit_barrier_after (last);
2976 if (flags & ECF_LONGJMP)
2977 current_function_calls_longjmp = 1, sibcall_failure = 1;
2979 /* If this function is returning into a memory location marked as
2980 readonly, it means it is initializing that location. But we normally
2981 treat functions as not clobbering such locations, so we need to
2982 specify that this one does. */
2983 if (target != 0 && GET_CODE (target) == MEM
2984 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
2985 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
2987 /* If value type not void, return an rtx for the value. */
2989 /* If there are cleanups to be called, don't use a hard reg as target.
2990 We need to double check this and see if it matters anymore. */
2991 if (any_pending_cleanups (1))
2993 if (target && REG_P (target)
2994 && REGNO (target) < FIRST_PSEUDO_REGISTER)
2996 sibcall_failure = 1;
2999 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3002 target = const0_rtx;
3004 else if (structure_value_addr)
3006 if (target == 0 || GET_CODE (target) != MEM)
3008 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3009 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3010 structure_value_addr));
3011 MEM_SET_IN_STRUCT_P (target,
3012 AGGREGATE_TYPE_P (TREE_TYPE (exp)));
3015 else if (pcc_struct_value)
3017 /* This is the special C++ case where we need to
3018 know what the true target was. We take care to
3019 never use this value more than once in one expression. */
3020 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3021 copy_to_reg (valreg));
3022 MEM_SET_IN_STRUCT_P (target, AGGREGATE_TYPE_P (TREE_TYPE (exp)));
3024 /* Handle calls that return values in multiple non-contiguous locations.
3025 The Irix 6 ABI has examples of this. */
3026 else if (GET_CODE (valreg) == PARALLEL)
3028 int bytes = int_size_in_bytes (TREE_TYPE (exp));
3032 target = assign_stack_temp (TYPE_MODE (TREE_TYPE (exp)),
3034 MEM_SET_IN_STRUCT_P (target, AGGREGATE_TYPE_P (TREE_TYPE (exp)));
3035 preserve_temp_slots (target);
3038 if (! rtx_equal_p (target, valreg))
3039 emit_group_store (target, valreg, bytes,
3040 TYPE_ALIGN (TREE_TYPE (exp)));
3042 /* We can not support sibling calls for this case. */
3043 sibcall_failure = 1;
3046 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3047 && GET_MODE (target) == GET_MODE (valreg))
3049 /* TARGET and VALREG cannot be equal at this point because the
3050 latter would not have REG_FUNCTION_VALUE_P true, while the
3051 former would if it were referring to the same register.
3053 If they refer to the same register, this move will be a no-op,
3054 except when function inlining is being done. */
3055 emit_move_insn (target, valreg);
3057 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3058 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3060 target = copy_to_reg (valreg);
3062 #ifdef PROMOTE_FUNCTION_RETURN
3063 /* If we promoted this return value, make the proper SUBREG. TARGET
3064 might be const0_rtx here, so be careful. */
3065 if (GET_CODE (target) == REG
3066 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3067 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3069 tree type = TREE_TYPE (exp);
3070 int unsignedp = TREE_UNSIGNED (type);
3072 /* If we don't promote as expected, something is wrong. */
3073 if (GET_MODE (target)
3074 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3077 target = gen_rtx_SUBREG (TYPE_MODE (type), target, 0);
3078 SUBREG_PROMOTED_VAR_P (target) = 1;
3079 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
3083 /* If size of args is variable or this was a constructor call for a stack
3084 argument, restore saved stack-pointer value. */
3086 if (old_stack_level)
3088 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3089 pending_stack_adjust = old_pending_adj;
3090 stack_arg_under_construction = old_stack_arg_under_construction;
3091 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3092 stack_usage_map = initial_stack_usage_map;
3093 sibcall_failure = 1;
3095 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3097 #ifdef REG_PARM_STACK_SPACE
3100 restore_fixed_argument_area (save_area, argblock,
3101 high_to_save, low_to_save);
3105 /* If we saved any argument areas, restore them. */
3106 for (i = 0; i < num_actuals; i++)
3107 if (args[i].save_area)
3109 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3111 = gen_rtx_MEM (save_mode,
3112 memory_address (save_mode,
3113 XEXP (args[i].stack_slot, 0)));
3115 if (save_mode != BLKmode)
3116 emit_move_insn (stack_area, args[i].save_area);
3118 emit_block_move (stack_area,
3119 validize_mem (args[i].save_area),
3120 GEN_INT (args[i].size.constant),
3124 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3125 stack_usage_map = initial_stack_usage_map;
3128 /* If this was alloca, record the new stack level for nonlocal gotos.
3129 Check for the handler slots since we might not have a save area
3130 for non-local gotos. */
3132 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3133 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3137 /* Free up storage we no longer need. */
3138 for (i = 0; i < num_actuals; ++i)
3139 if (args[i].aligned_regs)
3140 free (args[i].aligned_regs);
3144 /* Undo the fake expand_start_target_temps we did earlier. If
3145 there had been any cleanups created, we've already set
3147 expand_end_target_temps ();
3150 insns = get_insns ();
3155 tail_call_insns = insns;
3157 /* If something prevents making this a sibling call,
3158 zero out the sequence. */
3159 if (sibcall_failure)
3160 tail_call_insns = NULL_RTX;
3161 /* Restore the pending stack adjustment now that we have
3162 finished generating the sibling call sequence. */
3164 pending_stack_adjust = save_pending_stack_adjust;
3165 stack_pointer_delta = save_stack_pointer_delta;
3168 normal_call_insns = insns;
3171 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3172 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3173 can happen if the arguments to this function call an inline
3174 function who's expansion contains another CALL_PLACEHOLDER.
3176 If there are any C_Ps in any of these sequences, replace them
3177 with their normal call. */
3179 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3180 if (GET_CODE (insn) == CALL_INSN
3181 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3182 replace_call_placeholder (insn, sibcall_use_normal);
3184 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3185 if (GET_CODE (insn) == CALL_INSN
3186 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3187 replace_call_placeholder (insn, sibcall_use_normal);
3189 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3190 if (GET_CODE (insn) == CALL_INSN
3191 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3192 replace_call_placeholder (insn, sibcall_use_normal);
3194 /* If this was a potential tail recursion site, then emit a
3195 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3196 One of them will be selected later. */
3197 if (tail_recursion_insns || tail_call_insns)
3199 /* The tail recursion label must be kept around. We could expose
3200 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3201 and makes determining true tail recursion sites difficult.
3203 So we set LABEL_PRESERVE_P here, then clear it when we select
3204 one of the call sequences after rtl generation is complete. */
3205 if (tail_recursion_insns)
3206 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3207 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3209 tail_recursion_insns,
3210 tail_recursion_label));
3213 emit_insns (normal_call_insns);
3215 currently_expanding_call--;
3220 /* Returns nonzero if FUN is the symbol for a library function which can
3224 libfunc_nothrow (fun)
3227 if (fun == throw_libfunc
3228 || fun == rethrow_libfunc
3229 || fun == sjthrow_libfunc
3230 || fun == sjpopnthrow_libfunc)
3236 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3237 The RETVAL parameter specifies whether return value needs to be saved, other
3238 parameters are documented in the emit_library_call function bellow. */
3240 emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3245 enum machine_mode outmode;
3249 /* Total size in bytes of all the stack-parms scanned so far. */
3250 struct args_size args_size;
3251 /* Size of arguments before any adjustments (such as rounding). */
3252 struct args_size original_args_size;
3253 register int argnum;
3257 struct args_size alignment_pad;
3259 CUMULATIVE_ARGS args_so_far;
3260 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
3261 struct args_size offset; struct args_size size; rtx save_area; };
3263 int old_inhibit_defer_pop = inhibit_defer_pop;
3264 rtx call_fusage = 0;
3267 int pcc_struct_value = 0;
3268 int struct_value_size = 0;
3270 int reg_parm_stack_space = 0;
3273 #ifdef REG_PARM_STACK_SPACE
3274 /* Define the boundary of the register parm stack space that needs to be
3276 int low_to_save = -1, high_to_save = 0;
3277 rtx save_area = 0; /* Place that it is saved */
3280 /* Size of the stack reserved for parameter registers. */
3281 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3282 char *initial_stack_usage_map = stack_usage_map;
3284 #ifdef REG_PARM_STACK_SPACE
3285 #ifdef MAYBE_REG_PARM_STACK_SPACE
3286 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3288 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3294 else if (fn_type == 2)
3298 if (libfunc_nothrow (fun))
3299 flags |= ECF_NOTHROW;
3301 #ifdef PREFERRED_STACK_BOUNDARY
3302 /* Ensure current function's preferred stack boundary is at least
3304 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3305 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3308 /* If this kind of value comes back in memory,
3309 decide where in memory it should come back. */
3310 if (outmode != VOIDmode && aggregate_value_p (type_for_mode (outmode, 0)))
3312 #ifdef PCC_STATIC_STRUCT_RETURN
3314 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
3316 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3317 pcc_struct_value = 1;
3319 value = gen_reg_rtx (outmode);
3320 #else /* not PCC_STATIC_STRUCT_RETURN */
3321 struct_value_size = GET_MODE_SIZE (outmode);
3322 if (value != 0 && GET_CODE (value) == MEM)
3325 mem_value = assign_stack_temp (outmode, GET_MODE_SIZE (outmode), 0);
3328 /* This call returns a big structure. */
3329 flags &= ~(ECF_CONST | ECF_PURE);
3332 /* ??? Unfinished: must pass the memory address as an argument. */
3334 /* Copy all the libcall-arguments out of the varargs data
3335 and into a vector ARGVEC.
3337 Compute how to pass each argument. We only support a very small subset
3338 of the full argument passing conventions to limit complexity here since
3339 library functions shouldn't have many args. */
3341 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3342 bzero ((char *) argvec, (nargs + 1) * sizeof (struct arg));
3344 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3346 args_size.constant = 0;
3351 /* Now we are about to start emitting insns that can be deleted
3352 if a libcall is deleted. */
3353 if (flags & (ECF_CONST | ECF_PURE))
3358 /* If there's a structure value address to be passed,
3359 either pass it in the special place, or pass it as an extra argument. */
3360 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3362 rtx addr = XEXP (mem_value, 0);
3365 /* Make sure it is a reasonable operand for a move or push insn. */
3366 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3367 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3368 addr = force_operand (addr, NULL_RTX);
3370 argvec[count].value = addr;
3371 argvec[count].mode = Pmode;
3372 argvec[count].partial = 0;
3374 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3375 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3376 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3380 locate_and_pad_parm (Pmode, NULL_TREE,
3381 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3384 argvec[count].reg != 0,
3386 NULL_TREE, &args_size, &argvec[count].offset,
3387 &argvec[count].size, &alignment_pad);
3390 if (argvec[count].reg == 0 || argvec[count].partial != 0
3391 || reg_parm_stack_space > 0)
3392 args_size.constant += argvec[count].size.constant;
3394 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3399 for (; count < nargs; count++)
3401 rtx val = va_arg (p, rtx);
3402 enum machine_mode mode = va_arg (p, enum machine_mode);
3404 /* We cannot convert the arg value to the mode the library wants here;
3405 must do it earlier where we know the signedness of the arg. */
3407 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3410 /* On some machines, there's no way to pass a float to a library fcn.
3411 Pass it as a double instead. */
3412 #ifdef LIBGCC_NEEDS_DOUBLE
3413 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3414 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3417 /* There's no need to call protect_from_queue, because
3418 either emit_move_insn or emit_push_insn will do that. */
3420 /* Make sure it is a reasonable operand for a move or push insn. */
3421 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3422 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3423 val = force_operand (val, NULL_RTX);
3425 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3426 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3428 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
3429 be viewed as just an efficiency improvement. */
3430 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
3431 emit_move_insn (slot, val);
3432 val = force_operand (XEXP (slot, 0), NULL_RTX);
3437 argvec[count].value = val;
3438 argvec[count].mode = mode;
3440 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3442 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3443 argvec[count].partial
3444 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3446 argvec[count].partial = 0;
3449 locate_and_pad_parm (mode, NULL_TREE,
3450 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3453 argvec[count].reg != 0,
3455 NULL_TREE, &args_size, &argvec[count].offset,
3456 &argvec[count].size, &alignment_pad);
3458 if (argvec[count].size.var)
3461 if (reg_parm_stack_space == 0 && argvec[count].partial)
3462 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3464 if (argvec[count].reg == 0 || argvec[count].partial != 0
3465 || reg_parm_stack_space > 0)
3466 args_size.constant += argvec[count].size.constant;
3468 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3471 #ifdef FINAL_REG_PARM_STACK_SPACE
3472 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3475 /* If this machine requires an external definition for library
3476 functions, write one out. */
3477 assemble_external_libcall (fun);
3479 original_args_size = args_size;
3480 #ifdef PREFERRED_STACK_BOUNDARY
3481 args_size.constant = (((args_size.constant
3482 + stack_pointer_delta
3486 - stack_pointer_delta);
3489 args_size.constant = MAX (args_size.constant,
3490 reg_parm_stack_space);
3492 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3493 args_size.constant -= reg_parm_stack_space;
3496 if (args_size.constant > current_function_outgoing_args_size)
3497 current_function_outgoing_args_size = args_size.constant;
3499 if (ACCUMULATE_OUTGOING_ARGS)
3501 /* Since the stack pointer will never be pushed, it is possible for
3502 the evaluation of a parm to clobber something we have already
3503 written to the stack. Since most function calls on RISC machines
3504 do not use the stack, this is uncommon, but must work correctly.
3506 Therefore, we save any area of the stack that was already written
3507 and that we are using. Here we set up to do this by making a new
3508 stack usage map from the old one.
3510 Another approach might be to try to reorder the argument
3511 evaluations to avoid this conflicting stack usage. */
3513 needed = args_size.constant;
3515 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3516 /* Since we will be writing into the entire argument area, the
3517 map must be allocated for its entire size, not just the part that
3518 is the responsibility of the caller. */
3519 needed += reg_parm_stack_space;
3522 #ifdef ARGS_GROW_DOWNWARD
3523 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3526 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3529 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3531 if (initial_highest_arg_in_use)
3532 bcopy (initial_stack_usage_map, stack_usage_map,
3533 initial_highest_arg_in_use);
3535 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3536 bzero (&stack_usage_map[initial_highest_arg_in_use],
3537 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3540 /* The address of the outgoing argument list must not be copied to a
3541 register here, because argblock would be left pointing to the
3542 wrong place after the call to allocate_dynamic_stack_space below.
3545 argblock = virtual_outgoing_args_rtx;
3550 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3553 #ifdef PREFERRED_STACK_BOUNDARY
3554 /* If we push args individually in reverse order, perform stack alignment
3555 before the first push (the last arg). */
3556 if (argblock == 0 && PUSH_ARGS_REVERSED)
3557 anti_adjust_stack (GEN_INT (args_size.constant
3558 - original_args_size.constant));
3561 if (PUSH_ARGS_REVERSED)
3572 #ifdef REG_PARM_STACK_SPACE
3573 if (ACCUMULATE_OUTGOING_ARGS)
3575 /* The argument list is the property of the called routine and it
3576 may clobber it. If the fixed area has been used for previous
3577 parameters, we must save and restore it.
3579 Here we compute the boundary of the that needs to be saved, if any. */
3581 #ifdef ARGS_GROW_DOWNWARD
3582 for (count = 0; count < reg_parm_stack_space + 1; count++)
3584 for (count = 0; count < reg_parm_stack_space; count++)
3587 if (count >= highest_outgoing_arg_in_use
3588 || stack_usage_map[count] == 0)
3591 if (low_to_save == -1)
3592 low_to_save = count;
3594 high_to_save = count;
3597 if (low_to_save >= 0)
3599 int num_to_save = high_to_save - low_to_save + 1;
3600 enum machine_mode save_mode
3601 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3604 /* If we don't have the required alignment, must do this in BLKmode. */
3605 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3606 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3607 save_mode = BLKmode;
3609 #ifdef ARGS_GROW_DOWNWARD
3610 stack_area = gen_rtx_MEM (save_mode,
3611 memory_address (save_mode,
3612 plus_constant (argblock,
3615 stack_area = gen_rtx_MEM (save_mode,
3616 memory_address (save_mode,
3617 plus_constant (argblock,
3620 if (save_mode == BLKmode)
3622 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3623 emit_block_move (validize_mem (save_area), stack_area,
3624 GEN_INT (num_to_save), PARM_BOUNDARY);
3628 save_area = gen_reg_rtx (save_mode);
3629 emit_move_insn (save_area, stack_area);
3635 /* Push the args that need to be pushed. */
3637 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3638 are to be pushed. */
3639 for (count = 0; count < nargs; count++, argnum += inc)
3641 register enum machine_mode mode = argvec[argnum].mode;
3642 register rtx val = argvec[argnum].value;
3643 rtx reg = argvec[argnum].reg;
3644 int partial = argvec[argnum].partial;
3645 int lower_bound = 0, upper_bound = 0, i;
3647 if (! (reg != 0 && partial == 0))
3649 if (ACCUMULATE_OUTGOING_ARGS)
3651 /* If this is being stored into a pre-allocated, fixed-size,
3652 stack area, save any previous data at that location. */
3654 #ifdef ARGS_GROW_DOWNWARD
3655 /* stack_slot is negative, but we want to index stack_usage_map
3656 with positive values. */
3657 upper_bound = -argvec[argnum].offset.constant + 1;
3658 lower_bound = upper_bound - argvec[argnum].size.constant;
3660 lower_bound = argvec[argnum].offset.constant;
3661 upper_bound = lower_bound + argvec[argnum].size.constant;
3664 for (i = lower_bound; i < upper_bound; i++)
3665 if (stack_usage_map[i]
3666 /* Don't store things in the fixed argument area at this
3667 point; it has already been saved. */
3668 && i > reg_parm_stack_space)
3671 if (i != upper_bound)
3673 /* We need to make a save area. See what mode we can make
3675 enum machine_mode save_mode
3676 = mode_for_size (argvec[argnum].size.constant
3684 plus_constant (argblock,
3685 argvec[argnum].offset.constant)));
3686 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3688 emit_move_insn (argvec[argnum].save_area, stack_area);
3692 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
3693 argblock, GEN_INT (argvec[argnum].offset.constant),
3694 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3696 /* Now mark the segment we just used. */
3697 if (ACCUMULATE_OUTGOING_ARGS)
3698 for (i = lower_bound; i < upper_bound; i++)
3699 stack_usage_map[i] = 1;
3705 #ifdef PREFERRED_STACK_BOUNDARY
3706 /* If we pushed args in forward order, perform stack alignment
3707 after pushing the last arg. */
3708 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3709 anti_adjust_stack (GEN_INT (args_size.constant
3710 - original_args_size.constant));
3713 if (PUSH_ARGS_REVERSED)
3718 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
3720 /* Now load any reg parms into their regs. */
3722 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3723 are to be pushed. */
3724 for (count = 0; count < nargs; count++, argnum += inc)
3726 register rtx val = argvec[argnum].value;
3727 rtx reg = argvec[argnum].reg;
3728 int partial = argvec[argnum].partial;
3730 /* Handle calls that pass values in multiple non-contiguous
3731 locations. The PA64 has examples of this for library calls. */
3732 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3733 emit_group_load (reg, val,
3734 GET_MODE_SIZE (GET_MODE (val)),
3735 GET_MODE_ALIGNMENT (GET_MODE (val)));
3736 else if (reg != 0 && partial == 0)
3737 emit_move_insn (reg, val);
3742 /* Any regs containing parms remain in use through the call. */
3743 for (count = 0; count < nargs; count++)
3745 rtx reg = argvec[count].reg;
3746 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3747 use_group_regs (&call_fusage, reg);
3749 use_reg (&call_fusage, reg);
3752 /* Pass the function the address in which to return a structure value. */
3753 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
3755 emit_move_insn (struct_value_rtx,
3757 force_operand (XEXP (mem_value, 0),
3759 if (GET_CODE (struct_value_rtx) == REG)
3760 use_reg (&call_fusage, struct_value_rtx);
3763 /* Don't allow popping to be deferred, since then
3764 cse'ing of library calls could delete a call and leave the pop. */
3766 valreg = (mem_value == 0 && outmode != VOIDmode
3767 ? hard_libcall_value (outmode) : NULL_RTX);
3769 #ifdef PREFERRED_STACK_BOUNDARY
3770 /* Stack must to be properly aligned now. */
3771 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
3775 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3776 will set inhibit_defer_pop to that value. */
3777 /* The return type is needed to decide how many bytes the function pops.
3778 Signedness plays no role in that, so for simplicity, we pretend it's
3779 always signed. We also assume that the list of arguments passed has
3780 no impact, so we pretend it is unknown. */
3783 get_identifier (XSTR (orgfun, 0)),
3784 build_function_type (outmode == VOIDmode ? void_type_node
3785 : type_for_mode (outmode, 0), NULL_TREE),
3786 original_args_size.constant, args_size.constant,
3788 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
3790 old_inhibit_defer_pop + 1, call_fusage, flags);
3792 /* Now restore inhibit_defer_pop to its actual original value. */
3795 /* If call is cse'able, make appropriate pair of reg-notes around it.
3796 Test valreg so we don't crash; may safely ignore `const'
3797 if return type is void. Disable for PARALLEL return values, because
3798 we have no way to move such values into a pseudo register. */
3799 if ((flags & (ECF_CONST | ECF_PURE))
3800 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
3803 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3807 /* Construct an "equal form" for the value which mentions all the
3808 arguments in order as well as the function name. */
3809 for (i = 0; i < nargs; i++)
3810 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
3811 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
3813 insns = get_insns ();
3816 if (flags & ECF_PURE)
3817 note = gen_rtx_EXPR_LIST (VOIDmode,
3818 gen_rtx_USE (VOIDmode,
3819 gen_rtx_MEM (BLKmode,
3820 gen_rtx_SCRATCH (VOIDmode))), note);
3822 emit_libcall_block (insns, temp, valreg, note);
3826 else if (flags & (ECF_CONST | ECF_PURE))
3828 /* Otherwise, just write out the sequence without a note. */
3829 rtx insns = get_insns ();
3836 /* Copy the value to the right place. */
3837 if (outmode != VOIDmode && retval)
3843 if (value != mem_value)
3844 emit_move_insn (value, mem_value);
3846 else if (value != 0)
3847 emit_move_insn (value, hard_libcall_value (outmode));
3849 value = hard_libcall_value (outmode);
3852 if (ACCUMULATE_OUTGOING_ARGS)
3854 #ifdef REG_PARM_STACK_SPACE
3857 enum machine_mode save_mode = GET_MODE (save_area);
3858 #ifdef ARGS_GROW_DOWNWARD
3860 = gen_rtx_MEM (save_mode,
3861 memory_address (save_mode,
3862 plus_constant (argblock,
3866 = gen_rtx_MEM (save_mode,
3867 memory_address (save_mode,
3868 plus_constant (argblock, low_to_save)));
3870 if (save_mode != BLKmode)
3871 emit_move_insn (stack_area, save_area);
3873 emit_block_move (stack_area, validize_mem (save_area),
3874 GEN_INT (high_to_save - low_to_save + 1),
3879 /* If we saved any argument areas, restore them. */
3880 for (count = 0; count < nargs; count++)
3881 if (argvec[count].save_area)
3883 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
3885 = gen_rtx_MEM (save_mode,
3888 plus_constant (argblock,
3889 argvec[count].offset.constant)));
3891 emit_move_insn (stack_area, argvec[count].save_area);
3894 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3895 stack_usage_map = initial_stack_usage_map;
3902 /* Output a library call to function FUN (a SYMBOL_REF rtx)
3903 (emitting the queue unless NO_QUEUE is nonzero),
3904 for a value of mode OUTMODE,
3905 with NARGS different arguments, passed as alternating rtx values
3906 and machine_modes to convert them to.
3907 The rtx values should have been passed through protect_from_queue already.
3909 FN_TYPE will is zero for `normal' calls, one for `const' calls, wich
3910 which will be enclosed in REG_LIBCALL/REG_RETVAL notes and two for `pure'
3911 calls, that are handled like `const' calls with extra
3912 (use (memory (scratch)). */
3915 emit_library_call VPARAMS((rtx orgfun, int fn_type, enum machine_mode outmode,
3918 #ifndef ANSI_PROTOTYPES
3921 enum machine_mode outmode;
3926 VA_START (p, nargs);
3928 #ifndef ANSI_PROTOTYPES
3929 orgfun = va_arg (p, rtx);
3930 fn_type = va_arg (p, int);
3931 outmode = va_arg (p, enum machine_mode);
3932 nargs = va_arg (p, int);
3935 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
3940 /* Like emit_library_call except that an extra argument, VALUE,
3941 comes second and says where to store the result.
3942 (If VALUE is zero, this function chooses a convenient way
3943 to return the value.
3945 This function returns an rtx for where the value is to be found.
3946 If VALUE is nonzero, VALUE is returned. */
3949 emit_library_call_value VPARAMS((rtx orgfun, rtx value, int fn_type,
3950 enum machine_mode outmode, int nargs, ...))
3952 #ifndef ANSI_PROTOTYPES
3956 enum machine_mode outmode;
3961 VA_START (p, nargs);
3963 #ifndef ANSI_PROTOTYPES
3964 orgfun = va_arg (p, rtx);
3965 value = va_arg (p, rtx);
3966 fn_type = va_arg (p, int);
3967 outmode = va_arg (p, enum machine_mode);
3968 nargs = va_arg (p, int);
3971 value = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode, nargs, p);
3979 /* Return an rtx which represents a suitable home on the stack
3980 given TYPE, the type of the argument looking for a home.
3981 This is called only for BLKmode arguments.
3983 SIZE is the size needed for this target.
3984 ARGS_ADDR is the address of the bottom of the argument block for this call.
3985 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
3986 if this machine uses push insns. */
3989 target_for_arg (type, size, args_addr, offset)
3993 struct args_size offset;
3996 rtx offset_rtx = ARGS_SIZE_RTX (offset);
3998 /* We do not call memory_address if possible,
3999 because we want to address as close to the stack
4000 as possible. For non-variable sized arguments,
4001 this will be stack-pointer relative addressing. */
4002 if (GET_CODE (offset_rtx) == CONST_INT)
4003 target = plus_constant (args_addr, INTVAL (offset_rtx));
4006 /* I have no idea how to guarantee that this
4007 will work in the presence of register parameters. */
4008 target = gen_rtx_PLUS (Pmode, args_addr, offset_rtx);
4009 target = memory_address (QImode, target);
4012 return gen_rtx_MEM (BLKmode, target);
4016 /* Store a single argument for a function call
4017 into the register or memory area where it must be passed.
4018 *ARG describes the argument value and where to pass it.
4020 ARGBLOCK is the address of the stack-block for all the arguments,
4021 or 0 on a machine where arguments are pushed individually.
4023 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4024 so must be careful about how the stack is used.
4026 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4027 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4028 that we need not worry about saving and restoring the stack.
4030 FNDECL is the declaration of the function we are calling. */
4033 store_one_arg (arg, argblock, flags, variable_size,
4034 reg_parm_stack_space)
4035 struct arg_data *arg;
4038 int variable_size ATTRIBUTE_UNUSED;
4039 int reg_parm_stack_space;
4041 register tree pval = arg->tree_value;
4045 int i, lower_bound = 0, upper_bound = 0;
4047 if (TREE_CODE (pval) == ERROR_MARK)
4050 /* Push a new temporary level for any temporaries we make for
4054 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4056 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4057 save any previous data at that location. */
4058 if (argblock && ! variable_size && arg->stack)
4060 #ifdef ARGS_GROW_DOWNWARD
4061 /* stack_slot is negative, but we want to index stack_usage_map
4062 with positive values. */
4063 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4064 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4068 lower_bound = upper_bound - arg->size.constant;
4070 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4071 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4075 upper_bound = lower_bound + arg->size.constant;
4078 for (i = lower_bound; i < upper_bound; i++)
4079 if (stack_usage_map[i]
4080 /* Don't store things in the fixed argument area at this point;
4081 it has already been saved. */
4082 && i > reg_parm_stack_space)
4085 if (i != upper_bound)
4087 /* We need to make a save area. See what mode we can make it. */
4088 enum machine_mode save_mode
4089 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
4091 = gen_rtx_MEM (save_mode,
4092 memory_address (save_mode,
4093 XEXP (arg->stack_slot, 0)));
4095 if (save_mode == BLKmode)
4097 arg->save_area = assign_stack_temp (BLKmode,
4098 arg->size.constant, 0);
4099 MEM_SET_IN_STRUCT_P (arg->save_area,
4100 AGGREGATE_TYPE_P (TREE_TYPE
4101 (arg->tree_value)));
4102 preserve_temp_slots (arg->save_area);
4103 emit_block_move (validize_mem (arg->save_area), stack_area,
4104 GEN_INT (arg->size.constant),
4109 arg->save_area = gen_reg_rtx (save_mode);
4110 emit_move_insn (arg->save_area, stack_area);
4114 /* Now that we have saved any slots that will be overwritten by this
4115 store, mark all slots this store will use. We must do this before
4116 we actually expand the argument since the expansion itself may
4117 trigger library calls which might need to use the same stack slot. */
4118 if (argblock && ! variable_size && arg->stack)
4119 for (i = lower_bound; i < upper_bound; i++)
4120 stack_usage_map[i] = 1;
4123 /* If this isn't going to be placed on both the stack and in registers,
4124 set up the register and number of words. */
4125 if (! arg->pass_on_stack)
4126 reg = arg->reg, partial = arg->partial;
4128 if (reg != 0 && partial == 0)
4129 /* Being passed entirely in a register. We shouldn't be called in
4133 /* If this arg needs special alignment, don't load the registers
4135 if (arg->n_aligned_regs != 0)
4138 /* If this is being passed partially in a register, we can't evaluate
4139 it directly into its stack slot. Otherwise, we can. */
4140 if (arg->value == 0)
4142 /* stack_arg_under_construction is nonzero if a function argument is
4143 being evaluated directly into the outgoing argument list and
4144 expand_call must take special action to preserve the argument list
4145 if it is called recursively.
4147 For scalar function arguments stack_usage_map is sufficient to
4148 determine which stack slots must be saved and restored. Scalar
4149 arguments in general have pass_on_stack == 0.
4151 If this argument is initialized by a function which takes the
4152 address of the argument (a C++ constructor or a C function
4153 returning a BLKmode structure), then stack_usage_map is
4154 insufficient and expand_call must push the stack around the
4155 function call. Such arguments have pass_on_stack == 1.
4157 Note that it is always safe to set stack_arg_under_construction,
4158 but this generates suboptimal code if set when not needed. */
4160 if (arg->pass_on_stack)
4161 stack_arg_under_construction++;
4163 arg->value = expand_expr (pval,
4165 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4166 ? NULL_RTX : arg->stack,
4169 /* If we are promoting object (or for any other reason) the mode
4170 doesn't agree, convert the mode. */
4172 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4173 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4174 arg->value, arg->unsignedp);
4176 if (arg->pass_on_stack)
4177 stack_arg_under_construction--;
4180 /* Don't allow anything left on stack from computation
4181 of argument to alloca. */
4182 if (flags & ECF_MAY_BE_ALLOCA)
4183 do_pending_stack_adjust ();
4185 if (arg->value == arg->stack)
4187 /* If the value is already in the stack slot, we are done. */
4188 if (current_function_check_memory_usage && GET_CODE (arg->stack) == MEM)
4190 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4191 XEXP (arg->stack, 0), Pmode,
4192 ARGS_SIZE_RTX (arg->size),
4193 TYPE_MODE (sizetype),
4194 GEN_INT (MEMORY_USE_RW),
4195 TYPE_MODE (integer_type_node));
4198 else if (arg->mode != BLKmode)
4202 /* Argument is a scalar, not entirely passed in registers.
4203 (If part is passed in registers, arg->partial says how much
4204 and emit_push_insn will take care of putting it there.)
4206 Push it, and if its size is less than the
4207 amount of space allocated to it,
4208 also bump stack pointer by the additional space.
4209 Note that in C the default argument promotions
4210 will prevent such mismatches. */
4212 size = GET_MODE_SIZE (arg->mode);
4213 /* Compute how much space the push instruction will push.
4214 On many machines, pushing a byte will advance the stack
4215 pointer by a halfword. */
4216 #ifdef PUSH_ROUNDING
4217 size = PUSH_ROUNDING (size);
4221 /* Compute how much space the argument should get:
4222 round up to a multiple of the alignment for arguments. */
4223 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4224 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4225 / (PARM_BOUNDARY / BITS_PER_UNIT))
4226 * (PARM_BOUNDARY / BITS_PER_UNIT));
4228 /* This isn't already where we want it on the stack, so put it there.
4229 This can either be done with push or copy insns. */
4230 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX, 0,
4231 partial, reg, used - size, argblock,
4232 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4233 ARGS_SIZE_RTX (arg->alignment_pad));
4237 /* BLKmode, at least partly to be pushed. */
4239 register int excess;
4242 /* Pushing a nonscalar.
4243 If part is passed in registers, PARTIAL says how much
4244 and emit_push_insn will take care of putting it there. */
4246 /* Round its size up to a multiple
4247 of the allocation unit for arguments. */
4249 if (arg->size.var != 0)
4252 size_rtx = ARGS_SIZE_RTX (arg->size);
4256 /* PUSH_ROUNDING has no effect on us, because
4257 emit_push_insn for BLKmode is careful to avoid it. */
4258 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4259 + partial * UNITS_PER_WORD);
4260 size_rtx = expr_size (pval);
4263 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4264 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg, excess,
4265 argblock, ARGS_SIZE_RTX (arg->offset),
4266 reg_parm_stack_space,
4267 ARGS_SIZE_RTX (arg->alignment_pad));
4271 /* Unless this is a partially-in-register argument, the argument is now
4274 ??? Note that this can change arg->value from arg->stack to
4275 arg->stack_slot and it matters when they are not the same.
4276 It isn't totally clear that this is correct in all cases. */
4278 arg->value = arg->stack_slot;
4280 /* Once we have pushed something, pops can't safely
4281 be deferred during the rest of the arguments. */
4284 /* ANSI doesn't require a sequence point here,
4285 but PCC has one, so this will avoid some problems. */
4288 /* Free any temporary slots made in processing this argument. Show
4289 that we might have taken the address of something and pushed that
4291 preserve_temp_slots (NULL_RTX);