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, 2001, 2002, 2003 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
24 #include "coretypes.h"
38 #include "langhooks.h"
41 /* Decide whether a function's arguments should be processed
42 from first to last or from last to first.
44 They should if the stack and args grow in opposite directions, but
45 only if we have push insns. */
49 #ifndef PUSH_ARGS_REVERSED
50 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
51 #define PUSH_ARGS_REVERSED PUSH_ARGS
57 #ifndef PUSH_ARGS_REVERSED
58 #define PUSH_ARGS_REVERSED 0
61 #ifndef STACK_POINTER_OFFSET
62 #define STACK_POINTER_OFFSET 0
65 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
66 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
68 /* Data structure and subroutines used within expand_call. */
72 /* Tree node for this argument. */
74 /* Mode for value; TYPE_MODE unless promoted. */
75 enum machine_mode mode;
76 /* Current RTL value for argument, or 0 if it isn't precomputed. */
78 /* Initially-compute RTL value for argument; only for const functions. */
80 /* Register to pass this argument in, 0 if passed on stack, or an
81 PARALLEL if the arg is to be copied into multiple non-contiguous
84 /* Register to pass this argument in when generating tail call sequence.
85 This is not the same register as for normal calls on machines with
88 /* If REG was promoted from the actual mode of the argument expression,
89 indicates whether the promotion is sign- or zero-extended. */
91 /* Number of registers to use. 0 means put the whole arg in registers.
92 Also 0 if not passed in registers. */
94 /* Nonzero if argument must be passed on stack.
95 Note that some arguments may be passed on the stack
96 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
97 pass_on_stack identifies arguments that *cannot* go in registers. */
99 /* Offset of this argument from beginning of stack-args. */
100 struct args_size offset;
101 /* Similar, but offset to the start of the stack slot. Different from
102 OFFSET if this arg pads downward. */
103 struct args_size slot_offset;
104 /* Size of this argument on the stack, rounded up for any padding it gets,
105 parts of the argument passed in registers do not count.
106 If REG_PARM_STACK_SPACE is defined, then register parms
107 are counted here as well. */
108 struct args_size size;
109 /* Location on the stack at which parameter should be stored. The store
110 has already been done if STACK == VALUE. */
112 /* Location on the stack of the start of this argument slot. This can
113 differ from STACK if this arg pads downward. This location is known
114 to be aligned to FUNCTION_ARG_BOUNDARY. */
116 /* Place that this stack area has been saved, if needed. */
118 /* If an argument's alignment does not permit direct copying into registers,
119 copy in smaller-sized pieces into pseudos. These are stored in a
120 block pointed to by this field. The next field says how many
121 word-sized pseudos we made. */
124 /* The amount that the stack pointer needs to be adjusted to
125 force alignment for the next argument. */
126 struct args_size alignment_pad;
129 /* A vector of one char per byte of stack space. A byte if nonzero if
130 the corresponding stack location has been used.
131 This vector is used to prevent a function call within an argument from
132 clobbering any stack already set up. */
133 static char *stack_usage_map;
135 /* Size of STACK_USAGE_MAP. */
136 static int highest_outgoing_arg_in_use;
138 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
139 stack location's tail call argument has been already stored into the stack.
140 This bitmap is used to prevent sibling call optimization if function tries
141 to use parent's incoming argument slots when they have been already
142 overwritten with tail call arguments. */
143 static sbitmap stored_args_map;
145 /* stack_arg_under_construction is nonzero when an argument may be
146 initialized with a constructor call (including a C function that
147 returns a BLKmode struct) and expand_call must take special action
148 to make sure the object being constructed does not overlap the
149 argument list for the constructor call. */
150 int stack_arg_under_construction;
152 static int calls_function PARAMS ((tree, int));
153 static int calls_function_1 PARAMS ((tree, int));
155 static void emit_call_1 PARAMS ((rtx, tree, tree, HOST_WIDE_INT,
156 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
159 static void precompute_register_parameters PARAMS ((int,
162 static int store_one_arg PARAMS ((struct arg_data *, rtx, int, int,
164 static void store_unaligned_arguments_into_pseudos PARAMS ((struct arg_data *,
166 static int finalize_must_preallocate PARAMS ((int, int,
168 struct args_size *));
169 static void precompute_arguments PARAMS ((int, int,
171 static int compute_argument_block_size PARAMS ((int,
174 static void initialize_argument_information PARAMS ((int,
181 static void compute_argument_addresses PARAMS ((struct arg_data *,
183 static rtx rtx_for_function_call PARAMS ((tree, tree));
184 static void load_register_parameters PARAMS ((struct arg_data *,
187 static rtx emit_library_call_value_1 PARAMS ((int, rtx, rtx,
191 static int special_function_p PARAMS ((tree, int));
192 static rtx try_to_integrate PARAMS ((tree, tree, rtx,
194 static int check_sibcall_argument_overlap_1 PARAMS ((rtx));
195 static int check_sibcall_argument_overlap PARAMS ((rtx, struct arg_data *,
198 static int combine_pending_stack_adjustment_and_call
199 PARAMS ((int, struct args_size *, int));
200 static tree fix_unsafe_tree PARAMS ((tree));
202 #ifdef REG_PARM_STACK_SPACE
203 static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
204 static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
207 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
210 If WHICH is 0, return 1 if EXP contains a call to any function.
211 Actually, we only need return 1 if evaluating EXP would require pushing
212 arguments on the stack, but that is too difficult to compute, so we just
213 assume any function call might require the stack. */
215 static tree calls_function_save_exprs;
218 calls_function (exp, which)
224 calls_function_save_exprs = 0;
225 val = calls_function_1 (exp, which);
226 calls_function_save_exprs = 0;
230 /* Recursive function to do the work of above function. */
233 calls_function_1 (exp, which)
238 enum tree_code code = TREE_CODE (exp);
239 int class = TREE_CODE_CLASS (code);
240 int length = first_rtl_op (code);
242 /* If this code is language-specific, we don't know what it will do. */
243 if ((int) code >= NUM_TREE_CODES)
251 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
253 && (TYPE_RETURNS_STACK_DEPRESSED
254 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))))
256 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
257 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
259 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
261 & ECF_MAY_BE_ALLOCA))
270 for (tem = CONSTRUCTOR_ELTS (exp); tem != 0; tem = TREE_CHAIN (tem))
271 if (calls_function_1 (TREE_VALUE (tem), which))
278 if (SAVE_EXPR_RTL (exp) != 0)
280 if (value_member (exp, calls_function_save_exprs))
282 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
283 calls_function_save_exprs);
284 return (TREE_OPERAND (exp, 0) != 0
285 && calls_function_1 (TREE_OPERAND (exp, 0), which));
292 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
293 if (DECL_INITIAL (local) != 0
294 && calls_function_1 (DECL_INITIAL (local), which))
297 for (subblock = BLOCK_SUBBLOCKS (exp);
299 subblock = TREE_CHAIN (subblock))
300 if (calls_function_1 (subblock, which))
306 for (; exp != 0; exp = TREE_CHAIN (exp))
307 if (calls_function_1 (TREE_VALUE (exp), which))
315 /* Only expressions, references, and blocks can contain calls. */
316 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
319 for (i = 0; i < length; i++)
320 if (TREE_OPERAND (exp, i) != 0
321 && calls_function_1 (TREE_OPERAND (exp, i), which))
327 /* Force FUNEXP into a form suitable for the address of a CALL,
328 and return that as an rtx. Also load the static chain register
329 if FNDECL is a nested function.
331 CALL_FUSAGE points to a variable holding the prospective
332 CALL_INSN_FUNCTION_USAGE information. */
335 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen, sibcallp)
342 rtx static_chain_value = 0;
344 funexp = protect_from_queue (funexp, 0);
347 /* Get possible static chain value for nested function in C. */
348 static_chain_value = lookup_static_chain (fndecl);
350 /* Make a valid memory address and copy constants thru pseudo-regs,
351 but not for a constant address if -fno-function-cse. */
352 if (GET_CODE (funexp) != SYMBOL_REF)
353 /* If we are using registers for parameters, force the
354 function address into a register now. */
355 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
356 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
357 : memory_address (FUNCTION_MODE, funexp));
360 #ifndef NO_FUNCTION_CSE
361 if (optimize && ! flag_no_function_cse)
362 #ifdef NO_RECURSIVE_FUNCTION_CSE
363 if (fndecl != current_function_decl)
365 funexp = force_reg (Pmode, funexp);
369 if (static_chain_value != 0)
371 emit_move_insn (static_chain_rtx, static_chain_value);
373 if (GET_CODE (static_chain_rtx) == REG)
374 use_reg (call_fusage, static_chain_rtx);
380 /* Generate instructions to call function FUNEXP,
381 and optionally pop the results.
382 The CALL_INSN is the first insn generated.
384 FNDECL is the declaration node of the function. This is given to the
385 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
387 FUNTYPE is the data type of the function. This is given to the macro
388 RETURN_POPS_ARGS to determine whether this function pops its own args.
389 We used to allow an identifier for library functions, but that doesn't
390 work when the return type is an aggregate type and the calling convention
391 says that the pointer to this aggregate is to be popped by the callee.
393 STACK_SIZE is the number of bytes of arguments on the stack,
394 ROUNDED_STACK_SIZE is that number rounded up to
395 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
396 both to put into the call insn and to generate explicit popping
399 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
400 It is zero if this call doesn't want a structure value.
402 NEXT_ARG_REG is the rtx that results from executing
403 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
404 just after all the args have had their registers assigned.
405 This could be whatever you like, but normally it is the first
406 arg-register beyond those used for args in this call,
407 or 0 if all the arg-registers are used in this call.
408 It is passed on to `gen_call' so you can put this info in the call insn.
410 VALREG is a hard register in which a value is returned,
411 or 0 if the call does not return a value.
413 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
414 the args to this call were processed.
415 We restore `inhibit_defer_pop' to that value.
417 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
418 denote registers used by the called function. */
421 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
422 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
423 call_fusage, ecf_flags, args_so_far)
425 tree fndecl ATTRIBUTE_UNUSED;
426 tree funtype ATTRIBUTE_UNUSED;
427 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
428 HOST_WIDE_INT rounded_stack_size;
429 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
430 rtx next_arg_reg ATTRIBUTE_UNUSED;
432 int old_inhibit_defer_pop;
435 CUMULATIVE_ARGS *args_so_far ATTRIBUTE_UNUSED;
437 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
439 int already_popped = 0;
440 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
441 #if defined (HAVE_call) && defined (HAVE_call_value)
442 rtx struct_value_size_rtx;
443 struct_value_size_rtx = GEN_INT (struct_value_size);
446 #ifdef CALL_POPS_ARGS
447 n_popped += CALL_POPS_ARGS (* args_so_far);
450 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
451 and we don't want to load it into a register as an optimization,
452 because prepare_call_address already did it if it should be done. */
453 if (GET_CODE (funexp) != SYMBOL_REF)
454 funexp = memory_address (FUNCTION_MODE, funexp);
456 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
457 if ((ecf_flags & ECF_SIBCALL)
458 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
459 && (n_popped > 0 || stack_size == 0))
461 rtx n_pop = GEN_INT (n_popped);
464 /* If this subroutine pops its own args, record that in the call insn
465 if possible, for the sake of frame pointer elimination. */
468 pat = GEN_SIBCALL_VALUE_POP (valreg,
469 gen_rtx_MEM (FUNCTION_MODE, funexp),
470 rounded_stack_size_rtx, next_arg_reg,
473 pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
474 rounded_stack_size_rtx, next_arg_reg, n_pop);
476 emit_call_insn (pat);
482 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
483 /* If the target has "call" or "call_value" insns, then prefer them
484 if no arguments are actually popped. If the target does not have
485 "call" or "call_value" insns, then we must use the popping versions
486 even if the call has no arguments to pop. */
487 #if defined (HAVE_call) && defined (HAVE_call_value)
488 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
489 && n_popped > 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
491 if (HAVE_call_pop && HAVE_call_value_pop)
494 rtx n_pop = GEN_INT (n_popped);
497 /* If this subroutine pops its own args, record that in the call insn
498 if possible, for the sake of frame pointer elimination. */
501 pat = GEN_CALL_VALUE_POP (valreg,
502 gen_rtx_MEM (FUNCTION_MODE, funexp),
503 rounded_stack_size_rtx, next_arg_reg, n_pop);
505 pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
506 rounded_stack_size_rtx, next_arg_reg, n_pop);
508 emit_call_insn (pat);
514 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
515 if ((ecf_flags & ECF_SIBCALL)
516 && HAVE_sibcall && HAVE_sibcall_value)
519 emit_call_insn (GEN_SIBCALL_VALUE (valreg,
520 gen_rtx_MEM (FUNCTION_MODE, funexp),
521 rounded_stack_size_rtx,
522 next_arg_reg, NULL_RTX));
524 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
525 rounded_stack_size_rtx, next_arg_reg,
526 struct_value_size_rtx));
531 #if defined (HAVE_call) && defined (HAVE_call_value)
532 if (HAVE_call && HAVE_call_value)
535 emit_call_insn (GEN_CALL_VALUE (valreg,
536 gen_rtx_MEM (FUNCTION_MODE, funexp),
537 rounded_stack_size_rtx, next_arg_reg,
540 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
541 rounded_stack_size_rtx, next_arg_reg,
542 struct_value_size_rtx));
548 /* Find the CALL insn we just emitted. */
549 for (call_insn = get_last_insn ();
550 call_insn && GET_CODE (call_insn) != CALL_INSN;
551 call_insn = PREV_INSN (call_insn))
557 /* Mark memory as used for "pure" function call. */
558 if (ecf_flags & ECF_PURE)
562 gen_rtx_USE (VOIDmode,
563 gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode))),
566 /* Put the register usage information on the CALL. If there is already
567 some usage information, put ours at the end. */
568 if (CALL_INSN_FUNCTION_USAGE (call_insn))
572 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
573 link = XEXP (link, 1))
576 XEXP (link, 1) = call_fusage;
579 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
581 /* If this is a const call, then set the insn's unchanging bit. */
582 if (ecf_flags & (ECF_CONST | ECF_PURE))
583 CONST_OR_PURE_CALL_P (call_insn) = 1;
585 /* If this call can't throw, attach a REG_EH_REGION reg note to that
587 if (ecf_flags & ECF_NOTHROW)
588 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
589 REG_NOTES (call_insn));
591 if (ecf_flags & ECF_NORETURN)
592 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_NORETURN, const0_rtx,
593 REG_NOTES (call_insn));
594 if (ecf_flags & ECF_ALWAYS_RETURN)
595 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN, const0_rtx,
596 REG_NOTES (call_insn));
598 if (ecf_flags & ECF_RETURNS_TWICE)
600 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_SETJMP, const0_rtx,
601 REG_NOTES (call_insn));
602 current_function_calls_setjmp = 1;
605 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
607 /* Restore this now, so that we do defer pops for this call's args
608 if the context of the call as a whole permits. */
609 inhibit_defer_pop = old_inhibit_defer_pop;
614 CALL_INSN_FUNCTION_USAGE (call_insn)
615 = gen_rtx_EXPR_LIST (VOIDmode,
616 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
617 CALL_INSN_FUNCTION_USAGE (call_insn));
618 rounded_stack_size -= n_popped;
619 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
620 stack_pointer_delta -= n_popped;
623 if (!ACCUMULATE_OUTGOING_ARGS)
625 /* If returning from the subroutine does not automatically pop the args,
626 we need an instruction to pop them sooner or later.
627 Perhaps do it now; perhaps just record how much space to pop later.
629 If returning from the subroutine does pop the args, indicate that the
630 stack pointer will be changed. */
632 if (rounded_stack_size != 0)
634 if (ecf_flags & ECF_SP_DEPRESSED)
635 /* Just pretend we did the pop. */
636 stack_pointer_delta -= rounded_stack_size;
637 else if (flag_defer_pop && inhibit_defer_pop == 0
638 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
639 pending_stack_adjust += rounded_stack_size;
641 adjust_stack (rounded_stack_size_rtx);
644 /* When we accumulate outgoing args, we must avoid any stack manipulations.
645 Restore the stack pointer to its original value now. Usually
646 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
647 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
648 popping variants of functions exist as well.
650 ??? We may optimize similar to defer_pop above, but it is
651 probably not worthwhile.
653 ??? It will be worthwhile to enable combine_stack_adjustments even for
656 anti_adjust_stack (GEN_INT (n_popped));
659 /* Determine if the function identified by NAME and FNDECL is one with
660 special properties we wish to know about.
662 For example, if the function might return more than one time (setjmp), then
663 set RETURNS_TWICE to a nonzero value.
665 Similarly set LONGJMP for if the function is in the longjmp family.
667 Set MALLOC for any of the standard memory allocation functions which
668 allocate from the heap.
670 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
671 space from the stack such as alloca. */
674 special_function_p (fndecl, flags)
678 if (! (flags & ECF_MALLOC)
679 && fndecl && DECL_NAME (fndecl)
680 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
681 /* Exclude functions not at the file scope, or not `extern',
682 since they are not the magic functions we would otherwise
684 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
686 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
687 const char *tname = name;
689 /* We assume that alloca will always be called by name. It
690 makes no sense to pass it as a pointer-to-function to
691 anything that does not understand its behavior. */
692 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
694 && ! strcmp (name, "alloca"))
695 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
697 && ! strcmp (name, "__builtin_alloca"))))
698 flags |= ECF_MAY_BE_ALLOCA;
700 /* Disregard prefix _, __ or __x. */
703 if (name[1] == '_' && name[2] == 'x')
705 else if (name[1] == '_')
714 && (! strcmp (tname, "setjmp")
715 || ! strcmp (tname, "setjmp_syscall")))
717 && ! strcmp (tname, "sigsetjmp"))
719 && ! strcmp (tname, "savectx")))
720 flags |= ECF_RETURNS_TWICE;
723 && ! strcmp (tname, "siglongjmp"))
724 flags |= ECF_LONGJMP;
726 else if ((tname[0] == 'q' && tname[1] == 's'
727 && ! strcmp (tname, "qsetjmp"))
728 || (tname[0] == 'v' && tname[1] == 'f'
729 && ! strcmp (tname, "vfork")))
730 flags |= ECF_RETURNS_TWICE;
732 else if (tname[0] == 'l' && tname[1] == 'o'
733 && ! strcmp (tname, "longjmp"))
734 flags |= ECF_LONGJMP;
736 else if ((tname[0] == 'f' && tname[1] == 'o'
737 && ! strcmp (tname, "fork"))
738 /* Linux specific: __clone. check NAME to insist on the
739 leading underscores, to avoid polluting the ISO / POSIX
741 || (name[0] == '_' && name[1] == '_'
742 && ! strcmp (tname, "clone"))
743 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
744 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
746 || ((tname[5] == 'p' || tname[5] == 'e')
747 && tname[6] == '\0'))))
748 flags |= ECF_FORK_OR_EXEC;
750 /* Do not add any more malloc-like functions to this list,
751 instead mark them as malloc functions using the malloc attribute.
752 Note, realloc is not suitable for attribute malloc since
753 it may return the same address across multiple calls.
754 C++ operator new is not suitable because it is not required
755 to return a unique pointer; indeed, the standard placement new
756 just returns its argument. */
757 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl))) == Pmode
758 && (! strcmp (tname, "malloc")
759 || ! strcmp (tname, "calloc")
760 || ! strcmp (tname, "strdup")))
766 /* Return nonzero when tree represent call to longjmp. */
769 setjmp_call_p (fndecl)
772 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
775 /* Return true when exp contains alloca call. */
780 if (TREE_CODE (exp) == CALL_EXPR
781 && TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
782 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
784 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
785 0) & ECF_MAY_BE_ALLOCA))
790 /* Detect flags (function attributes) from the function decl or type node. */
793 flags_from_decl_or_type (exp)
798 /* ??? We can't set IS_MALLOC for function types? */
801 type = TREE_TYPE (exp);
803 /* The function exp may have the `malloc' attribute. */
804 if (DECL_P (exp) && DECL_IS_MALLOC (exp))
807 /* The function exp may have the `pure' attribute. */
808 if (DECL_P (exp) && DECL_IS_PURE (exp))
809 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
811 if (TREE_NOTHROW (exp))
812 flags |= ECF_NOTHROW;
815 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
816 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
818 if (TREE_THIS_VOLATILE (exp))
819 flags |= ECF_NORETURN;
821 /* Mark if the function returns with the stack pointer depressed. We
822 cannot consider it pure or constant in that case. */
823 if (TREE_CODE (type) == FUNCTION_TYPE && TYPE_RETURNS_STACK_DEPRESSED (type))
825 flags |= ECF_SP_DEPRESSED;
826 flags &= ~(ECF_PURE | ECF_CONST | ECF_LIBCALL_BLOCK);
832 /* Precompute all register parameters as described by ARGS, storing values
833 into fields within the ARGS array.
835 NUM_ACTUALS indicates the total number elements in the ARGS array.
837 Set REG_PARM_SEEN if we encounter a register parameter. */
840 precompute_register_parameters (num_actuals, args, reg_parm_seen)
842 struct arg_data *args;
849 for (i = 0; i < num_actuals; i++)
850 if (args[i].reg != 0 && ! args[i].pass_on_stack)
854 if (args[i].value == 0)
857 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
859 preserve_temp_slots (args[i].value);
862 /* ANSI doesn't require a sequence point here,
863 but PCC has one, so this will avoid some problems. */
867 /* If the value is a non-legitimate constant, force it into a
868 pseudo now. TLS symbols sometimes need a call to resolve. */
869 if (CONSTANT_P (args[i].value)
870 && !LEGITIMATE_CONSTANT_P (args[i].value))
871 args[i].value = force_reg (args[i].mode, args[i].value);
873 /* If we are to promote the function arg to a wider mode,
876 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
878 = convert_modes (args[i].mode,
879 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
880 args[i].value, args[i].unsignedp);
882 /* If the value is expensive, and we are inside an appropriately
883 short loop, put the value into a pseudo and then put the pseudo
886 For small register classes, also do this if this call uses
887 register parameters. This is to avoid reload conflicts while
888 loading the parameters registers. */
890 if ((! (GET_CODE (args[i].value) == REG
891 || (GET_CODE (args[i].value) == SUBREG
892 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
893 && args[i].mode != BLKmode
894 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
895 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
896 || preserve_subexpressions_p ()))
897 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
901 #ifdef REG_PARM_STACK_SPACE
903 /* The argument list is the property of the called routine and it
904 may clobber it. If the fixed area has been used for previous
905 parameters, we must save and restore it. */
908 save_fixed_argument_area (reg_parm_stack_space, argblock,
909 low_to_save, high_to_save)
910 int reg_parm_stack_space;
918 /* Compute the boundary of the area that needs to be saved, if any. */
919 high = reg_parm_stack_space;
920 #ifdef ARGS_GROW_DOWNWARD
923 if (high > highest_outgoing_arg_in_use)
924 high = highest_outgoing_arg_in_use;
926 for (low = 0; low < high; low++)
927 if (stack_usage_map[low] != 0)
930 enum machine_mode save_mode;
935 while (stack_usage_map[--high] == 0)
939 *high_to_save = high;
941 num_to_save = high - low + 1;
942 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
944 /* If we don't have the required alignment, must do this
946 if ((low & (MIN (GET_MODE_SIZE (save_mode),
947 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
950 #ifdef ARGS_GROW_DOWNWARD
955 stack_area = gen_rtx_MEM (save_mode,
956 memory_address (save_mode,
957 plus_constant (argblock,
960 set_mem_align (stack_area, PARM_BOUNDARY);
961 if (save_mode == BLKmode)
963 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
964 emit_block_move (validize_mem (save_area), stack_area,
965 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
969 save_area = gen_reg_rtx (save_mode);
970 emit_move_insn (save_area, stack_area);
980 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
986 enum machine_mode save_mode = GET_MODE (save_area);
990 #ifdef ARGS_GROW_DOWNWARD
991 delta = -high_to_save;
995 stack_area = gen_rtx_MEM (save_mode,
996 memory_address (save_mode,
997 plus_constant (argblock, delta)));
998 set_mem_align (stack_area, PARM_BOUNDARY);
1000 if (save_mode != BLKmode)
1001 emit_move_insn (stack_area, save_area);
1003 emit_block_move (stack_area, validize_mem (save_area),
1004 GEN_INT (high_to_save - low_to_save + 1),
1005 BLOCK_OP_CALL_PARM);
1007 #endif /* REG_PARM_STACK_SPACE */
1009 /* If any elements in ARGS refer to parameters that are to be passed in
1010 registers, but not in memory, and whose alignment does not permit a
1011 direct copy into registers. Copy the values into a group of pseudos
1012 which we will later copy into the appropriate hard registers.
1014 Pseudos for each unaligned argument will be stored into the array
1015 args[argnum].aligned_regs. The caller is responsible for deallocating
1016 the aligned_regs array if it is nonzero. */
1019 store_unaligned_arguments_into_pseudos (args, num_actuals)
1020 struct arg_data *args;
1025 for (i = 0; i < num_actuals; i++)
1026 if (args[i].reg != 0 && ! args[i].pass_on_stack
1027 && args[i].mode == BLKmode
1028 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1029 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1031 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1032 int big_endian_correction = 0;
1034 args[i].n_aligned_regs
1035 = args[i].partial ? args[i].partial
1036 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1038 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
1039 * args[i].n_aligned_regs);
1041 /* Structures smaller than a word are aligned to the least
1042 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1043 this means we must skip the empty high order bytes when
1044 calculating the bit offset. */
1045 if (BYTES_BIG_ENDIAN
1046 && bytes < UNITS_PER_WORD)
1047 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1049 for (j = 0; j < args[i].n_aligned_regs; j++)
1051 rtx reg = gen_reg_rtx (word_mode);
1052 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1053 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1055 args[i].aligned_regs[j] = reg;
1057 /* There is no need to restrict this code to loading items
1058 in TYPE_ALIGN sized hunks. The bitfield instructions can
1059 load up entire word sized registers efficiently.
1061 ??? This may not be needed anymore.
1062 We use to emit a clobber here but that doesn't let later
1063 passes optimize the instructions we emit. By storing 0 into
1064 the register later passes know the first AND to zero out the
1065 bitfield being set in the register is unnecessary. The store
1066 of 0 will be deleted as will at least the first AND. */
1068 emit_move_insn (reg, const0_rtx);
1070 bytes -= bitsize / BITS_PER_UNIT;
1071 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
1072 extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1073 word_mode, word_mode,
1080 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1083 NUM_ACTUALS is the total number of parameters.
1085 N_NAMED_ARGS is the total number of named arguments.
1087 FNDECL is the tree code for the target of this call (if known)
1089 ARGS_SO_FAR holds state needed by the target to know where to place
1092 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1093 for arguments which are passed in registers.
1095 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1096 and may be modified by this routine.
1098 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1099 flags which may may be modified by this routine. */
1102 initialize_argument_information (num_actuals, args, args_size, n_named_args,
1103 actparms, fndecl, args_so_far,
1104 reg_parm_stack_space, old_stack_level,
1105 old_pending_adj, must_preallocate,
1107 int num_actuals ATTRIBUTE_UNUSED;
1108 struct arg_data *args;
1109 struct args_size *args_size;
1110 int n_named_args ATTRIBUTE_UNUSED;
1113 CUMULATIVE_ARGS *args_so_far;
1114 int reg_parm_stack_space;
1115 rtx *old_stack_level;
1116 int *old_pending_adj;
1117 int *must_preallocate;
1120 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1123 /* Count arg position in order args appear. */
1126 struct args_size alignment_pad;
1130 args_size->constant = 0;
1133 /* In this loop, we consider args in the order they are written.
1134 We fill up ARGS from the front or from the back if necessary
1135 so that in any case the first arg to be pushed ends up at the front. */
1137 if (PUSH_ARGS_REVERSED)
1139 i = num_actuals - 1, inc = -1;
1140 /* In this case, must reverse order of args
1141 so that we compute and push the last arg first. */
1148 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1149 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1151 tree type = TREE_TYPE (TREE_VALUE (p));
1153 enum machine_mode mode;
1155 args[i].tree_value = TREE_VALUE (p);
1157 /* Replace erroneous argument with constant zero. */
1158 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1159 args[i].tree_value = integer_zero_node, type = integer_type_node;
1161 /* If TYPE is a transparent union, pass things the way we would
1162 pass the first field of the union. We have already verified that
1163 the modes are the same. */
1164 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1165 type = TREE_TYPE (TYPE_FIELDS (type));
1167 /* Decide where to pass this arg.
1169 args[i].reg is nonzero if all or part is passed in registers.
1171 args[i].partial is nonzero if part but not all is passed in registers,
1172 and the exact value says how many words are passed in registers.
1174 args[i].pass_on_stack is nonzero if the argument must at least be
1175 computed on the stack. It may then be loaded back into registers
1176 if args[i].reg is nonzero.
1178 These decisions are driven by the FUNCTION_... macros and must agree
1179 with those made by function.c. */
1181 /* See if this argument should be passed by invisible reference. */
1182 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1183 && contains_placeholder_p (TYPE_SIZE (type)))
1184 || TREE_ADDRESSABLE (type)
1185 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1186 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1187 type, argpos < n_named_args)
1191 /* If we're compiling a thunk, pass through invisible
1192 references instead of making a copy. */
1193 if (current_function_is_thunk
1194 #ifdef FUNCTION_ARG_CALLEE_COPIES
1195 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1196 type, argpos < n_named_args)
1197 /* If it's in a register, we must make a copy of it too. */
1198 /* ??? Is this a sufficient test? Is there a better one? */
1199 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1200 && REG_P (DECL_RTL (args[i].tree_value)))
1201 && ! TREE_ADDRESSABLE (type))
1205 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1206 new object from the argument. If we are passing by
1207 invisible reference, the callee will do that for us, so we
1208 can strip off the TARGET_EXPR. This is not always safe,
1209 but it is safe in the only case where this is a useful
1210 optimization; namely, when the argument is a plain object.
1211 In that case, the frontend is just asking the backend to
1212 make a bitwise copy of the argument. */
1214 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1215 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1216 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1217 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1219 args[i].tree_value = build1 (ADDR_EXPR,
1220 build_pointer_type (type),
1221 args[i].tree_value);
1222 type = build_pointer_type (type);
1224 else if (TREE_CODE (args[i].tree_value) == TARGET_EXPR)
1226 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1227 We implement this by passing the address of the temporary
1228 rather than expanding it into another allocated slot. */
1229 args[i].tree_value = build1 (ADDR_EXPR,
1230 build_pointer_type (type),
1231 args[i].tree_value);
1232 type = build_pointer_type (type);
1236 /* We make a copy of the object and pass the address to the
1237 function being called. */
1240 if (!COMPLETE_TYPE_P (type)
1241 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1242 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1243 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1244 STACK_CHECK_MAX_VAR_SIZE))))
1246 /* This is a variable-sized object. Make space on the stack
1248 rtx size_rtx = expr_size (TREE_VALUE (p));
1250 if (*old_stack_level == 0)
1252 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1253 *old_pending_adj = pending_stack_adjust;
1254 pending_stack_adjust = 0;
1257 copy = gen_rtx_MEM (BLKmode,
1258 allocate_dynamic_stack_space
1259 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1260 set_mem_attributes (copy, type, 1);
1263 copy = assign_temp (type, 0, 1, 0);
1265 store_expr (args[i].tree_value, copy, 0);
1266 *ecf_flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
1268 args[i].tree_value = build1 (ADDR_EXPR,
1269 build_pointer_type (type),
1270 make_tree (type, copy));
1271 type = build_pointer_type (type);
1275 mode = TYPE_MODE (type);
1276 unsignedp = TREE_UNSIGNED (type);
1278 #ifdef PROMOTE_FUNCTION_ARGS
1279 mode = promote_mode (type, mode, &unsignedp, 1);
1282 args[i].unsignedp = unsignedp;
1283 args[i].mode = mode;
1285 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1286 argpos < n_named_args);
1287 #ifdef FUNCTION_INCOMING_ARG
1288 /* If this is a sibling call and the machine has register windows, the
1289 register window has to be unwinded before calling the routine, so
1290 arguments have to go into the incoming registers. */
1291 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1292 argpos < n_named_args);
1294 args[i].tail_call_reg = args[i].reg;
1297 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1300 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1301 argpos < n_named_args);
1304 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1306 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1307 it means that we are to pass this arg in the register(s) designated
1308 by the PARALLEL, but also to pass it in the stack. */
1309 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1310 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1311 args[i].pass_on_stack = 1;
1313 /* If this is an addressable type, we must preallocate the stack
1314 since we must evaluate the object into its final location.
1316 If this is to be passed in both registers and the stack, it is simpler
1318 if (TREE_ADDRESSABLE (type)
1319 || (args[i].pass_on_stack && args[i].reg != 0))
1320 *must_preallocate = 1;
1322 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1323 we cannot consider this function call constant. */
1324 if (TREE_ADDRESSABLE (type))
1325 *ecf_flags &= ~ECF_LIBCALL_BLOCK;
1327 /* Compute the stack-size of this argument. */
1328 if (args[i].reg == 0 || args[i].partial != 0
1329 || reg_parm_stack_space > 0
1330 || args[i].pass_on_stack)
1331 locate_and_pad_parm (mode, type,
1332 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1337 fndecl, args_size, &args[i].offset,
1338 &args[i].size, &alignment_pad);
1340 #ifndef ARGS_GROW_DOWNWARD
1341 args[i].slot_offset = *args_size;
1344 args[i].alignment_pad = alignment_pad;
1346 /* If a part of the arg was put into registers,
1347 don't include that part in the amount pushed. */
1348 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1349 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1350 / (PARM_BOUNDARY / BITS_PER_UNIT)
1351 * (PARM_BOUNDARY / BITS_PER_UNIT));
1353 /* Update ARGS_SIZE, the total stack space for args so far. */
1355 args_size->constant += args[i].size.constant;
1356 if (args[i].size.var)
1358 ADD_PARM_SIZE (*args_size, args[i].size.var);
1361 /* Since the slot offset points to the bottom of the slot,
1362 we must record it after incrementing if the args grow down. */
1363 #ifdef ARGS_GROW_DOWNWARD
1364 args[i].slot_offset = *args_size;
1366 args[i].slot_offset.constant = -args_size->constant;
1368 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1371 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1372 have been used, etc. */
1374 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1375 argpos < n_named_args);
1379 /* Update ARGS_SIZE to contain the total size for the argument block.
1380 Return the original constant component of the argument block's size.
1382 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1383 for arguments passed in registers. */
1386 compute_argument_block_size (reg_parm_stack_space, args_size,
1387 preferred_stack_boundary)
1388 int reg_parm_stack_space;
1389 struct args_size *args_size;
1390 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1392 int unadjusted_args_size = args_size->constant;
1394 /* For accumulate outgoing args mode we don't need to align, since the frame
1395 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1396 backends from generating misaligned frame sizes. */
1397 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1398 preferred_stack_boundary = STACK_BOUNDARY;
1400 /* Compute the actual size of the argument block required. The variable
1401 and constant sizes must be combined, the size may have to be rounded,
1402 and there may be a minimum required size. */
1406 args_size->var = ARGS_SIZE_TREE (*args_size);
1407 args_size->constant = 0;
1409 preferred_stack_boundary /= BITS_PER_UNIT;
1410 if (preferred_stack_boundary > 1)
1412 /* We don't handle this case yet. To handle it correctly we have
1413 to add the delta, round and subtract the delta.
1414 Currently no machine description requires this support. */
1415 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1417 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1420 if (reg_parm_stack_space > 0)
1423 = size_binop (MAX_EXPR, args_size->var,
1424 ssize_int (reg_parm_stack_space));
1426 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1427 /* The area corresponding to register parameters is not to count in
1428 the size of the block we need. So make the adjustment. */
1430 = size_binop (MINUS_EXPR, args_size->var,
1431 ssize_int (reg_parm_stack_space));
1437 preferred_stack_boundary /= BITS_PER_UNIT;
1438 if (preferred_stack_boundary < 1)
1439 preferred_stack_boundary = 1;
1440 args_size->constant = (((args_size->constant
1441 + stack_pointer_delta
1442 + preferred_stack_boundary - 1)
1443 / preferred_stack_boundary
1444 * preferred_stack_boundary)
1445 - stack_pointer_delta);
1447 args_size->constant = MAX (args_size->constant,
1448 reg_parm_stack_space);
1450 #ifdef MAYBE_REG_PARM_STACK_SPACE
1451 if (reg_parm_stack_space == 0)
1452 args_size->constant = 0;
1455 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1456 args_size->constant -= reg_parm_stack_space;
1459 return unadjusted_args_size;
1462 /* Precompute parameters as needed for a function call.
1464 FLAGS is mask of ECF_* constants.
1466 NUM_ACTUALS is the number of arguments.
1468 ARGS is an array containing information for each argument; this
1469 routine fills in the INITIAL_VALUE and VALUE fields for each
1470 precomputed argument. */
1473 precompute_arguments (flags, num_actuals, args)
1476 struct arg_data *args;
1480 /* If this function call is cse'able, precompute all the parameters.
1481 Note that if the parameter is constructed into a temporary, this will
1482 cause an additional copy because the parameter will be constructed
1483 into a temporary location and then copied into the outgoing arguments.
1484 If a parameter contains a call to alloca and this function uses the
1485 stack, precompute the parameter. */
1487 /* If we preallocated the stack space, and some arguments must be passed
1488 on the stack, then we must precompute any parameter which contains a
1489 function call which will store arguments on the stack.
1490 Otherwise, evaluating the parameter may clobber previous parameters
1491 which have already been stored into the stack. (we have code to avoid
1492 such case by saving the outgoing stack arguments, but it results in
1495 for (i = 0; i < num_actuals; i++)
1496 if ((flags & ECF_LIBCALL_BLOCK)
1497 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1499 enum machine_mode mode;
1501 /* If this is an addressable type, we cannot pre-evaluate it. */
1502 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1506 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1508 /* ANSI doesn't require a sequence point here,
1509 but PCC has one, so this will avoid some problems. */
1512 args[i].initial_value = args[i].value
1513 = protect_from_queue (args[i].value, 0);
1515 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1516 if (mode != args[i].mode)
1519 = convert_modes (args[i].mode, mode,
1520 args[i].value, args[i].unsignedp);
1521 #ifdef PROMOTE_FOR_CALL_ONLY
1522 /* CSE will replace this only if it contains args[i].value
1523 pseudo, so convert it down to the declared mode using
1525 if (GET_CODE (args[i].value) == REG
1526 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1528 args[i].initial_value
1529 = gen_lowpart_SUBREG (mode, args[i].value);
1530 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1531 SUBREG_PROMOTED_UNSIGNED_SET (args[i].initial_value,
1539 /* Given the current state of MUST_PREALLOCATE and information about
1540 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1541 compute and return the final value for MUST_PREALLOCATE. */
1544 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1545 int must_preallocate;
1547 struct arg_data *args;
1548 struct args_size *args_size;
1550 /* See if we have or want to preallocate stack space.
1552 If we would have to push a partially-in-regs parm
1553 before other stack parms, preallocate stack space instead.
1555 If the size of some parm is not a multiple of the required stack
1556 alignment, we must preallocate.
1558 If the total size of arguments that would otherwise create a copy in
1559 a temporary (such as a CALL) is more than half the total argument list
1560 size, preallocation is faster.
1562 Another reason to preallocate is if we have a machine (like the m88k)
1563 where stack alignment is required to be maintained between every
1564 pair of insns, not just when the call is made. However, we assume here
1565 that such machines either do not have push insns (and hence preallocation
1566 would occur anyway) or the problem is taken care of with
1569 if (! must_preallocate)
1571 int partial_seen = 0;
1572 int copy_to_evaluate_size = 0;
1575 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1577 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1579 else if (partial_seen && args[i].reg == 0)
1580 must_preallocate = 1;
1582 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1583 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1584 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1585 || TREE_CODE (args[i].tree_value) == COND_EXPR
1586 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1587 copy_to_evaluate_size
1588 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1591 if (copy_to_evaluate_size * 2 >= args_size->constant
1592 && args_size->constant > 0)
1593 must_preallocate = 1;
1595 return must_preallocate;
1598 /* If we preallocated stack space, compute the address of each argument
1599 and store it into the ARGS array.
1601 We need not ensure it is a valid memory address here; it will be
1602 validized when it is used.
1604 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1607 compute_argument_addresses (args, argblock, num_actuals)
1608 struct arg_data *args;
1614 rtx arg_reg = argblock;
1615 int i, arg_offset = 0;
1617 if (GET_CODE (argblock) == PLUS)
1618 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1620 for (i = 0; i < num_actuals; i++)
1622 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1623 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1626 /* Skip this parm if it will not be passed on the stack. */
1627 if (! args[i].pass_on_stack && args[i].reg != 0)
1630 if (GET_CODE (offset) == CONST_INT)
1631 addr = plus_constant (arg_reg, INTVAL (offset));
1633 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1635 addr = plus_constant (addr, arg_offset);
1636 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1637 set_mem_align (args[i].stack, PARM_BOUNDARY);
1638 set_mem_attributes (args[i].stack,
1639 TREE_TYPE (args[i].tree_value), 1);
1641 if (GET_CODE (slot_offset) == CONST_INT)
1642 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1644 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1646 addr = plus_constant (addr, arg_offset);
1647 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1648 set_mem_align (args[i].stack_slot, PARM_BOUNDARY);
1649 set_mem_attributes (args[i].stack_slot,
1650 TREE_TYPE (args[i].tree_value), 1);
1652 /* Function incoming arguments may overlap with sibling call
1653 outgoing arguments and we cannot allow reordering of reads
1654 from function arguments with stores to outgoing arguments
1655 of sibling calls. */
1656 set_mem_alias_set (args[i].stack, 0);
1657 set_mem_alias_set (args[i].stack_slot, 0);
1662 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1663 in a call instruction.
1665 FNDECL is the tree node for the target function. For an indirect call
1666 FNDECL will be NULL_TREE.
1668 ADDR is the operand 0 of CALL_EXPR for this call. */
1671 rtx_for_function_call (fndecl, addr)
1677 /* Get the function to call, in the form of RTL. */
1680 /* If this is the first use of the function, see if we need to
1681 make an external definition for it. */
1682 if (! TREE_USED (fndecl))
1684 assemble_external (fndecl);
1685 TREE_USED (fndecl) = 1;
1688 /* Get a SYMBOL_REF rtx for the function address. */
1689 funexp = XEXP (DECL_RTL (fndecl), 0);
1692 /* Generate an rtx (probably a pseudo-register) for the address. */
1695 funexp = expand_expr (addr, NULL_RTX, VOIDmode, 0);
1696 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1702 /* Do the register loads required for any wholly-register parms or any
1703 parms which are passed both on the stack and in a register. Their
1704 expressions were already evaluated.
1706 Mark all register-parms as living through the call, putting these USE
1707 insns in the CALL_INSN_FUNCTION_USAGE field.
1709 When IS_SIBCALL, perform the check_sibcall_overlap_argument_overlap
1710 checking, setting *SIBCALL_FAILURE if appropriate. */
1713 load_register_parameters (args, num_actuals, call_fusage, flags,
1714 is_sibcall, sibcall_failure)
1715 struct arg_data *args;
1720 int *sibcall_failure;
1724 #ifdef LOAD_ARGS_REVERSED
1725 for (i = num_actuals - 1; i >= 0; i--)
1727 for (i = 0; i < num_actuals; i++)
1730 rtx reg = ((flags & ECF_SIBCALL)
1731 ? args[i].tail_call_reg : args[i].reg);
1732 int partial = args[i].partial;
1737 rtx before_arg = get_last_insn ();
1738 /* Set to non-negative if must move a word at a time, even if just
1739 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1740 we just use a normal move insn. This value can be zero if the
1741 argument is a zero size structure with no fields. */
1742 nregs = (partial ? partial
1743 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1744 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1745 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1748 /* Handle calls that pass values in multiple non-contiguous
1749 locations. The Irix 6 ABI has examples of this. */
1751 if (GET_CODE (reg) == PARALLEL)
1752 emit_group_load (reg, args[i].value,
1753 int_size_in_bytes (TREE_TYPE (args[i].tree_value)));
1755 /* If simple case, just do move. If normal partial, store_one_arg
1756 has already loaded the register for us. In all other cases,
1757 load the register(s) from memory. */
1759 else if (nregs == -1)
1760 emit_move_insn (reg, args[i].value);
1762 /* If we have pre-computed the values to put in the registers in
1763 the case of non-aligned structures, copy them in now. */
1765 else if (args[i].n_aligned_regs != 0)
1766 for (j = 0; j < args[i].n_aligned_regs; j++)
1767 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1768 args[i].aligned_regs[j]);
1770 else if (partial == 0 || args[i].pass_on_stack)
1771 move_block_to_reg (REGNO (reg),
1772 validize_mem (args[i].value), nregs,
1775 /* When a parameter is a block, and perhaps in other cases, it is
1776 possible that it did a load from an argument slot that was
1777 already clobbered. */
1779 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
1780 *sibcall_failure = 1;
1782 /* Handle calls that pass values in multiple non-contiguous
1783 locations. The Irix 6 ABI has examples of this. */
1784 if (GET_CODE (reg) == PARALLEL)
1785 use_group_regs (call_fusage, reg);
1786 else if (nregs == -1)
1787 use_reg (call_fusage, reg);
1789 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1794 /* Try to integrate function. See expand_inline_function for documentation
1795 about the parameters. */
1798 try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1804 rtx structure_value_addr;
1809 rtx old_stack_level = 0;
1810 int reg_parm_stack_space = 0;
1812 #ifdef REG_PARM_STACK_SPACE
1813 #ifdef MAYBE_REG_PARM_STACK_SPACE
1814 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1816 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1820 before_call = get_last_insn ();
1822 timevar_push (TV_INTEGRATION);
1824 temp = expand_inline_function (fndecl, actparms, target,
1826 structure_value_addr);
1828 timevar_pop (TV_INTEGRATION);
1830 /* If inlining succeeded, return. */
1831 if (temp != (rtx) (size_t) - 1)
1833 if (ACCUMULATE_OUTGOING_ARGS)
1835 /* If the outgoing argument list must be preserved, push
1836 the stack before executing the inlined function if it
1839 i = reg_parm_stack_space;
1840 if (i > highest_outgoing_arg_in_use)
1841 i = highest_outgoing_arg_in_use;
1842 while (--i >= 0 && stack_usage_map[i] == 0)
1845 if (stack_arg_under_construction || i >= 0)
1848 = before_call ? NEXT_INSN (before_call) : get_insns ();
1849 rtx insn = NULL_RTX, seq;
1851 /* Look for a call in the inline function code.
1852 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1853 nonzero then there is a call and it is not necessary
1854 to scan the insns. */
1856 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1857 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1858 if (GET_CODE (insn) == CALL_INSN)
1863 /* Reserve enough stack space so that the largest
1864 argument list of any function call in the inline
1865 function does not overlap the argument list being
1866 evaluated. This is usually an overestimate because
1867 allocate_dynamic_stack_space reserves space for an
1868 outgoing argument list in addition to the requested
1869 space, but there is no way to ask for stack space such
1870 that an argument list of a certain length can be
1873 Add the stack space reserved for register arguments, if
1874 any, in the inline function. What is really needed is the
1875 largest value of reg_parm_stack_space in the inline
1876 function, but that is not available. Using the current
1877 value of reg_parm_stack_space is wrong, but gives
1878 correct results on all supported machines. */
1880 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1881 + reg_parm_stack_space);
1884 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1885 allocate_dynamic_stack_space (GEN_INT (adjust),
1886 NULL_RTX, BITS_PER_UNIT);
1889 emit_insn_before (seq, first_insn);
1890 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1895 /* If the result is equivalent to TARGET, return TARGET to simplify
1896 checks in store_expr. They can be equivalent but not equal in the
1897 case of a function that returns BLKmode. */
1898 if (temp != target && rtx_equal_p (temp, target))
1903 /* If inlining failed, mark FNDECL as needing to be compiled
1904 separately after all. If function was declared inline,
1906 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1907 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1909 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1910 warning ("called from here");
1912 (*lang_hooks.mark_addressable) (fndecl);
1913 return (rtx) (size_t) - 1;
1916 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1917 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1918 bytes, then we would need to push some additional bytes to pad the
1919 arguments. So, we compute an adjust to the stack pointer for an
1920 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1921 bytes. Then, when the arguments are pushed the stack will be perfectly
1922 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1923 be popped after the call. Returns the adjustment. */
1926 combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1928 preferred_unit_stack_boundary)
1929 int unadjusted_args_size;
1930 struct args_size *args_size;
1931 int preferred_unit_stack_boundary;
1933 /* The number of bytes to pop so that the stack will be
1934 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1935 HOST_WIDE_INT adjustment;
1936 /* The alignment of the stack after the arguments are pushed, if we
1937 just pushed the arguments without adjust the stack here. */
1938 HOST_WIDE_INT unadjusted_alignment;
1940 unadjusted_alignment
1941 = ((stack_pointer_delta + unadjusted_args_size)
1942 % preferred_unit_stack_boundary);
1944 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1945 as possible -- leaving just enough left to cancel out the
1946 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1947 PENDING_STACK_ADJUST is non-negative, and congruent to
1948 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1950 /* Begin by trying to pop all the bytes. */
1951 unadjusted_alignment
1952 = (unadjusted_alignment
1953 - (pending_stack_adjust % preferred_unit_stack_boundary));
1954 adjustment = pending_stack_adjust;
1955 /* Push enough additional bytes that the stack will be aligned
1956 after the arguments are pushed. */
1957 if (preferred_unit_stack_boundary > 1)
1959 if (unadjusted_alignment > 0)
1960 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1962 adjustment += unadjusted_alignment;
1965 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1966 bytes after the call. The right number is the entire
1967 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1968 by the arguments in the first place. */
1970 = pending_stack_adjust - adjustment + unadjusted_args_size;
1975 /* Scan X expression if it does not dereference any argument slots
1976 we already clobbered by tail call arguments (as noted in stored_args_map
1978 Return nonzero if X expression dereferences such argument slots,
1982 check_sibcall_argument_overlap_1 (x)
1993 code = GET_CODE (x);
1997 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1999 else if (GET_CODE (XEXP (x, 0)) == PLUS
2000 && XEXP (XEXP (x, 0), 0) ==
2001 current_function_internal_arg_pointer
2002 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
2003 i = INTVAL (XEXP (XEXP (x, 0), 1));
2007 #ifdef ARGS_GROW_DOWNWARD
2008 i = -i - GET_MODE_SIZE (GET_MODE (x));
2011 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
2012 if (i + k < stored_args_map->n_bits
2013 && TEST_BIT (stored_args_map, i + k))
2019 /* Scan all subexpressions. */
2020 fmt = GET_RTX_FORMAT (code);
2021 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2025 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2028 else if (*fmt == 'E')
2030 for (j = 0; j < XVECLEN (x, i); j++)
2031 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2038 /* Scan sequence after INSN if it does not dereference any argument slots
2039 we already clobbered by tail call arguments (as noted in stored_args_map
2040 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2041 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2042 should be 0). Return nonzero if sequence after INSN dereferences such argument
2043 slots, zero otherwise. */
2046 check_sibcall_argument_overlap (insn, arg, mark_stored_args_map)
2048 struct arg_data *arg;
2049 int mark_stored_args_map;
2053 if (insn == NULL_RTX)
2054 insn = get_insns ();
2056 insn = NEXT_INSN (insn);
2058 for (; insn; insn = NEXT_INSN (insn))
2060 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2063 if (mark_stored_args_map)
2065 #ifdef ARGS_GROW_DOWNWARD
2066 low = -arg->slot_offset.constant - arg->size.constant;
2068 low = arg->slot_offset.constant;
2071 for (high = low + arg->size.constant; low < high; low++)
2072 SET_BIT (stored_args_map, low);
2074 return insn != NULL_RTX;
2081 switch (unsafe_for_reeval (t))
2086 case 1: /* Mildly unsafe. */
2087 t = unsave_expr (t);
2090 case 2: /* Wildly unsafe. */
2092 tree var = build_decl (VAR_DECL, NULL_TREE,
2095 expand_expr (t, NULL_RTX, VOIDmode, EXPAND_NORMAL));
2106 /* Generate all the code for a function call
2107 and return an rtx for its value.
2108 Store the value in TARGET (specified as an rtx) if convenient.
2109 If the value is stored in TARGET then TARGET is returned.
2110 If IGNORE is nonzero, then we ignore the value of the function call. */
2113 expand_call (exp, target, ignore)
2118 /* Nonzero if we are currently expanding a call. */
2119 static int currently_expanding_call = 0;
2121 /* List of actual parameters. */
2122 tree actparms = TREE_OPERAND (exp, 1);
2123 /* RTX for the function to be called. */
2125 /* Sequence of insns to perform a tail recursive "call". */
2126 rtx tail_recursion_insns = NULL_RTX;
2127 /* Sequence of insns to perform a normal "call". */
2128 rtx normal_call_insns = NULL_RTX;
2129 /* Sequence of insns to perform a tail recursive "call". */
2130 rtx tail_call_insns = NULL_RTX;
2131 /* Data type of the function. */
2133 /* Declaration of the function being called,
2134 or 0 if the function is computed (not known by name). */
2137 int try_tail_call = 1;
2138 int try_tail_recursion = 1;
2141 /* Register in which non-BLKmode value will be returned,
2142 or 0 if no value or if value is BLKmode. */
2144 /* Address where we should return a BLKmode value;
2145 0 if value not BLKmode. */
2146 rtx structure_value_addr = 0;
2147 /* Nonzero if that address is being passed by treating it as
2148 an extra, implicit first parameter. Otherwise,
2149 it is passed by being copied directly into struct_value_rtx. */
2150 int structure_value_addr_parm = 0;
2151 /* Size of aggregate value wanted, or zero if none wanted
2152 or if we are using the non-reentrant PCC calling convention
2153 or expecting the value in registers. */
2154 HOST_WIDE_INT struct_value_size = 0;
2155 /* Nonzero if called function returns an aggregate in memory PCC style,
2156 by returning the address of where to find it. */
2157 int pcc_struct_value = 0;
2159 /* Number of actual parameters in this call, including struct value addr. */
2161 /* Number of named args. Args after this are anonymous ones
2162 and they must all go on the stack. */
2165 /* Vector of information about each argument.
2166 Arguments are numbered in the order they will be pushed,
2167 not the order they are written. */
2168 struct arg_data *args;
2170 /* Total size in bytes of all the stack-parms scanned so far. */
2171 struct args_size args_size;
2172 struct args_size adjusted_args_size;
2173 /* Size of arguments before any adjustments (such as rounding). */
2174 int unadjusted_args_size;
2175 /* Data on reg parms scanned so far. */
2176 CUMULATIVE_ARGS args_so_far;
2177 /* Nonzero if a reg parm has been scanned. */
2179 /* Nonzero if this is an indirect function call. */
2181 /* Nonzero if we must avoid push-insns in the args for this call.
2182 If stack space is allocated for register parameters, but not by the
2183 caller, then it is preallocated in the fixed part of the stack frame.
2184 So the entire argument block must then be preallocated (i.e., we
2185 ignore PUSH_ROUNDING in that case). */
2187 int must_preallocate = !PUSH_ARGS;
2189 /* Size of the stack reserved for parameter registers. */
2190 int reg_parm_stack_space = 0;
2192 /* Address of space preallocated for stack parms
2193 (on machines that lack push insns), or 0 if space not preallocated. */
2196 /* Mask of ECF_ flags. */
2198 /* Nonzero if this is a call to an inline function. */
2199 int is_integrable = 0;
2200 #ifdef REG_PARM_STACK_SPACE
2201 /* Define the boundary of the register parm stack space that needs to be
2203 int low_to_save, high_to_save;
2204 rtx save_area = 0; /* Place that it is saved */
2207 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2208 char *initial_stack_usage_map = stack_usage_map;
2209 int old_stack_arg_under_construction = 0;
2211 rtx old_stack_level = 0;
2212 int old_pending_adj = 0;
2213 int old_inhibit_defer_pop = inhibit_defer_pop;
2214 int old_stack_allocated;
2216 tree p = TREE_OPERAND (exp, 0);
2217 tree addr = TREE_OPERAND (exp, 0);
2219 /* The alignment of the stack, in bits. */
2220 HOST_WIDE_INT preferred_stack_boundary;
2221 /* The alignment of the stack, in bytes. */
2222 HOST_WIDE_INT preferred_unit_stack_boundary;
2224 /* See if this is "nothrow" function call. */
2225 if (TREE_NOTHROW (exp))
2226 flags |= ECF_NOTHROW;
2228 /* See if we can find a DECL-node for the actual function.
2229 As a result, decide whether this is a call to an integrable function. */
2231 fndecl = get_callee_fndecl (exp);
2235 && fndecl != current_function_decl
2236 && DECL_INLINE (fndecl)
2237 && DECL_SAVED_INSNS (fndecl)
2238 && DECL_SAVED_INSNS (fndecl)->inlinable)
2240 else if (! TREE_ADDRESSABLE (fndecl))
2242 /* In case this function later becomes inlinable,
2243 record that there was already a non-inline call to it.
2245 Use abstraction instead of setting TREE_ADDRESSABLE
2247 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2250 warning_with_decl (fndecl, "can't inline call to `%s'");
2251 warning ("called from here");
2253 (*lang_hooks.mark_addressable) (fndecl);
2256 flags |= flags_from_decl_or_type (fndecl);
2259 /* If we don't have specific function to call, see if we have a
2260 attributes set in the type. */
2262 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2264 #ifdef REG_PARM_STACK_SPACE
2265 #ifdef MAYBE_REG_PARM_STACK_SPACE
2266 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2268 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2272 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2273 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2274 must_preallocate = 1;
2277 /* Warn if this value is an aggregate type,
2278 regardless of which calling convention we are using for it. */
2279 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2280 warning ("function call has aggregate value");
2282 /* Set up a place to return a structure. */
2284 /* Cater to broken compilers. */
2285 if (aggregate_value_p (exp))
2287 /* This call returns a big structure. */
2288 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
2290 #ifdef PCC_STATIC_STRUCT_RETURN
2292 pcc_struct_value = 1;
2293 /* Easier than making that case work right. */
2296 /* In case this is a static function, note that it has been
2298 if (! TREE_ADDRESSABLE (fndecl))
2299 (*lang_hooks.mark_addressable) (fndecl);
2303 #else /* not PCC_STATIC_STRUCT_RETURN */
2305 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2307 if (CALL_EXPR_HAS_RETURN_SLOT_ADDR (exp))
2309 /* The structure value address arg is already in actparms.
2310 Pull it out. It might be nice to just leave it there, but
2311 we need to set structure_value_addr. */
2312 tree return_arg = TREE_VALUE (actparms);
2313 actparms = TREE_CHAIN (actparms);
2314 structure_value_addr = expand_expr (return_arg, NULL_RTX,
2315 VOIDmode, EXPAND_NORMAL);
2317 else if (target && GET_CODE (target) == MEM)
2318 structure_value_addr = XEXP (target, 0);
2321 /* For variable-sized objects, we must be called with a target
2322 specified. If we were to allocate space on the stack here,
2323 we would have no way of knowing when to free it. */
2324 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2326 mark_temp_addr_taken (d);
2327 structure_value_addr = XEXP (d, 0);
2331 #endif /* not PCC_STATIC_STRUCT_RETURN */
2334 /* If called function is inline, try to integrate it. */
2338 rtx temp = try_to_integrate (fndecl, actparms, target,
2339 ignore, TREE_TYPE (exp),
2340 structure_value_addr);
2341 if (temp != (rtx) (size_t) - 1)
2345 /* Figure out the amount to which the stack should be aligned. */
2346 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2348 /* Operand 0 is a pointer-to-function; get the type of the function. */
2349 funtype = TREE_TYPE (addr);
2350 if (! POINTER_TYPE_P (funtype))
2352 funtype = TREE_TYPE (funtype);
2354 /* See if this is a call to a function that can return more than once
2355 or a call to longjmp or malloc. */
2356 flags |= special_function_p (fndecl, flags);
2358 if (flags & ECF_MAY_BE_ALLOCA)
2359 current_function_calls_alloca = 1;
2361 /* If struct_value_rtx is 0, it means pass the address
2362 as if it were an extra parameter. */
2363 if (structure_value_addr && struct_value_rtx == 0)
2365 /* If structure_value_addr is a REG other than
2366 virtual_outgoing_args_rtx, we can use always use it. If it
2367 is not a REG, we must always copy it into a register.
2368 If it is virtual_outgoing_args_rtx, we must copy it to another
2369 register in some cases. */
2370 rtx temp = (GET_CODE (structure_value_addr) != REG
2371 || (ACCUMULATE_OUTGOING_ARGS
2372 && stack_arg_under_construction
2373 && structure_value_addr == virtual_outgoing_args_rtx)
2374 ? copy_addr_to_reg (structure_value_addr)
2375 : structure_value_addr);
2378 = tree_cons (error_mark_node,
2379 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2382 structure_value_addr_parm = 1;
2385 /* Count the arguments and set NUM_ACTUALS. */
2386 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2389 /* Compute number of named args.
2390 Normally, don't include the last named arg if anonymous args follow.
2391 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2392 (If no anonymous args follow, the result of list_length is actually
2393 one too large. This is harmless.)
2395 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2396 zero, this machine will be able to place unnamed args that were
2397 passed in registers into the stack. So treat all args as named.
2398 This allows the insns emitting for a specific argument list to be
2399 independent of the function declaration.
2401 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2402 reliable way to pass unnamed args in registers, so we must force
2403 them into memory. */
2405 if ((STRICT_ARGUMENT_NAMING
2406 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2407 && TYPE_ARG_TYPES (funtype) != 0)
2409 = (list_length (TYPE_ARG_TYPES (funtype))
2410 /* Don't include the last named arg. */
2411 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2412 /* Count the struct value address, if it is passed as a parm. */
2413 + structure_value_addr_parm);
2415 /* If we know nothing, treat all args as named. */
2416 n_named_args = num_actuals;
2418 /* Start updating where the next arg would go.
2420 On some machines (such as the PA) indirect calls have a different
2421 calling convention than normal calls. The last argument in
2422 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2424 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, fndecl);
2426 /* Make a vector to hold all the information about each arg. */
2427 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
2428 memset ((char *) args, 0, num_actuals * sizeof (struct arg_data));
2430 /* Build up entries in the ARGS array, compute the size of the
2431 arguments into ARGS_SIZE, etc. */
2432 initialize_argument_information (num_actuals, args, &args_size,
2433 n_named_args, actparms, fndecl,
2434 &args_so_far, reg_parm_stack_space,
2435 &old_stack_level, &old_pending_adj,
2436 &must_preallocate, &flags);
2440 /* If this function requires a variable-sized argument list, don't
2441 try to make a cse'able block for this call. We may be able to
2442 do this eventually, but it is too complicated to keep track of
2443 what insns go in the cse'able block and which don't. */
2445 flags &= ~ECF_LIBCALL_BLOCK;
2446 must_preallocate = 1;
2449 /* Now make final decision about preallocating stack space. */
2450 must_preallocate = finalize_must_preallocate (must_preallocate,
2454 /* If the structure value address will reference the stack pointer, we
2455 must stabilize it. We don't need to do this if we know that we are
2456 not going to adjust the stack pointer in processing this call. */
2458 if (structure_value_addr
2459 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2460 || reg_mentioned_p (virtual_outgoing_args_rtx,
2461 structure_value_addr))
2463 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2464 structure_value_addr = copy_to_reg (structure_value_addr);
2466 /* Tail calls can make things harder to debug, and we're traditionally
2467 pushed these optimizations into -O2. Don't try if we're already
2468 expanding a call, as that means we're an argument. Don't try if
2469 there's cleanups, as we know there's code to follow the call.
2471 If rtx_equal_function_value_matters is false, that means we've
2472 finished with regular parsing. Which means that some of the
2473 machinery we use to generate tail-calls is no longer in place.
2474 This is most often true of sjlj-exceptions, which we couldn't
2475 tail-call to anyway. */
2477 if (currently_expanding_call++ != 0
2478 || !flag_optimize_sibling_calls
2479 || !rtx_equal_function_value_matters
2480 || any_pending_cleanups (1)
2482 try_tail_call = try_tail_recursion = 0;
2484 /* Tail recursion fails, when we are not dealing with recursive calls. */
2485 if (!try_tail_recursion
2486 || TREE_CODE (addr) != ADDR_EXPR
2487 || TREE_OPERAND (addr, 0) != current_function_decl)
2488 try_tail_recursion = 0;
2490 /* Rest of purposes for tail call optimizations to fail. */
2492 #ifdef HAVE_sibcall_epilogue
2493 !HAVE_sibcall_epilogue
2498 /* Doing sibling call optimization needs some work, since
2499 structure_value_addr can be allocated on the stack.
2500 It does not seem worth the effort since few optimizable
2501 sibling calls will return a structure. */
2502 || structure_value_addr != NULL_RTX
2503 /* Check whether the target is able to optimize the call
2505 || !(*targetm.function_ok_for_sibcall) (fndecl, exp)
2506 /* Functions that do not return exactly once may not be sibcall
2508 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP | ECF_NORETURN))
2509 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2510 /* If this function requires more stack slots than the current
2511 function, we cannot change it into a sibling call. */
2512 || args_size.constant > current_function_args_size
2513 /* If the callee pops its own arguments, then it must pop exactly
2514 the same number of arguments as the current function. */
2515 || RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2516 != RETURN_POPS_ARGS (current_function_decl,
2517 TREE_TYPE (current_function_decl),
2518 current_function_args_size))
2521 if (try_tail_call || try_tail_recursion)
2524 actparms = NULL_TREE;
2525 /* Ok, we're going to give the tail call the old college try.
2526 This means we're going to evaluate the function arguments
2527 up to three times. There are two degrees of badness we can
2528 encounter, those that can be unsaved and those that can't.
2529 (See unsafe_for_reeval commentary for details.)
2531 Generate a new argument list. Pass safe arguments through
2532 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2533 For hard badness, evaluate them now and put their resulting
2534 rtx in a temporary VAR_DECL.
2536 initialize_argument_information has ordered the array for the
2537 order to be pushed, and we must remember this when reconstructing
2538 the original argument order. */
2540 if (PUSH_ARGS_REVERSED)
2549 i = num_actuals - 1;
2553 for (; i != end; i += inc)
2555 args[i].tree_value = fix_unsafe_tree (args[i].tree_value);
2556 /* We need to build actparms for optimize_tail_recursion. We can
2557 safely trash away TREE_PURPOSE, since it is unused by this
2559 if (try_tail_recursion)
2560 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2562 /* Do the same for the function address if it is an expression. */
2564 addr = fix_unsafe_tree (addr);
2565 /* Expanding one of those dangerous arguments could have added
2566 cleanups, but otherwise give it a whirl. */
2567 if (any_pending_cleanups (1))
2568 try_tail_call = try_tail_recursion = 0;
2571 /* Generate a tail recursion sequence when calling ourselves. */
2573 if (try_tail_recursion)
2575 /* We want to emit any pending stack adjustments before the tail
2576 recursion "call". That way we know any adjustment after the tail
2577 recursion call can be ignored if we indeed use the tail recursion
2579 int save_pending_stack_adjust = pending_stack_adjust;
2580 int save_stack_pointer_delta = stack_pointer_delta;
2582 /* Emit any queued insns now; otherwise they would end up in
2583 only one of the alternates. */
2586 /* Use a new sequence to hold any RTL we generate. We do not even
2587 know if we will use this RTL yet. The final decision can not be
2588 made until after RTL generation for the entire function is
2591 /* If expanding any of the arguments creates cleanups, we can't
2592 do a tailcall. So, we'll need to pop the pending cleanups
2593 list. If, however, all goes well, and there are no cleanups
2594 then the call to expand_start_target_temps will have no
2596 expand_start_target_temps ();
2597 if (optimize_tail_recursion (actparms, get_last_insn ()))
2599 if (any_pending_cleanups (1))
2600 try_tail_call = try_tail_recursion = 0;
2602 tail_recursion_insns = get_insns ();
2604 expand_end_target_temps ();
2607 /* Restore the original pending stack adjustment for the sibling and
2608 normal call cases below. */
2609 pending_stack_adjust = save_pending_stack_adjust;
2610 stack_pointer_delta = save_stack_pointer_delta;
2613 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2615 /* A fork duplicates the profile information, and an exec discards
2616 it. We can't rely on fork/exec to be paired. So write out the
2617 profile information we have gathered so far, and clear it. */
2618 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2619 is subject to race conditions, just as with multithreaded
2622 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__gcov_flush"),
2627 /* Ensure current function's preferred stack boundary is at least
2628 what we need. We don't have to increase alignment for recursive
2630 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2631 && fndecl != current_function_decl)
2632 cfun->preferred_stack_boundary = preferred_stack_boundary;
2634 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2636 function_call_count++;
2638 /* We want to make two insn chains; one for a sibling call, the other
2639 for a normal call. We will select one of the two chains after
2640 initial RTL generation is complete. */
2641 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2643 int sibcall_failure = 0;
2644 /* We want to emit any pending stack adjustments before the tail
2645 recursion "call". That way we know any adjustment after the tail
2646 recursion call can be ignored if we indeed use the tail recursion
2648 int save_pending_stack_adjust = 0;
2649 int save_stack_pointer_delta = 0;
2651 rtx before_call, next_arg_reg;
2655 /* Emit any queued insns now; otherwise they would end up in
2656 only one of the alternates. */
2659 /* State variables we need to save and restore between
2661 save_pending_stack_adjust = pending_stack_adjust;
2662 save_stack_pointer_delta = stack_pointer_delta;
2665 flags &= ~ECF_SIBCALL;
2667 flags |= ECF_SIBCALL;
2669 /* Other state variables that we must reinitialize each time
2670 through the loop (that are not initialized by the loop itself). */
2674 /* Start a new sequence for the normal call case.
2676 From this point on, if the sibling call fails, we want to set
2677 sibcall_failure instead of continuing the loop. */
2682 /* We know at this point that there are not currently any
2683 pending cleanups. If, however, in the process of evaluating
2684 the arguments we were to create some, we'll need to be
2685 able to get rid of them. */
2686 expand_start_target_temps ();
2689 /* Don't let pending stack adjusts add up to too much.
2690 Also, do all pending adjustments now if there is any chance
2691 this might be a call to alloca or if we are expanding a sibling
2692 call sequence or if we are calling a function that is to return
2693 with stack pointer depressed. */
2694 if (pending_stack_adjust >= 32
2695 || (pending_stack_adjust > 0
2696 && (flags & (ECF_MAY_BE_ALLOCA | ECF_SP_DEPRESSED)))
2698 do_pending_stack_adjust ();
2700 /* When calling a const function, we must pop the stack args right away,
2701 so that the pop is deleted or moved with the call. */
2702 if (pass && (flags & ECF_LIBCALL_BLOCK))
2705 #ifdef FINAL_REG_PARM_STACK_SPACE
2706 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2709 /* Precompute any arguments as needed. */
2711 precompute_arguments (flags, num_actuals, args);
2713 /* Now we are about to start emitting insns that can be deleted
2714 if a libcall is deleted. */
2715 if (pass && (flags & (ECF_LIBCALL_BLOCK | ECF_MALLOC)))
2718 adjusted_args_size = args_size;
2719 /* Compute the actual size of the argument block required. The variable
2720 and constant sizes must be combined, the size may have to be rounded,
2721 and there may be a minimum required size. When generating a sibcall
2722 pattern, do not round up, since we'll be re-using whatever space our
2724 unadjusted_args_size
2725 = compute_argument_block_size (reg_parm_stack_space,
2726 &adjusted_args_size,
2728 : preferred_stack_boundary));
2730 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2732 /* The argument block when performing a sibling call is the
2733 incoming argument block. */
2736 argblock = virtual_incoming_args_rtx;
2738 #ifdef STACK_GROWS_DOWNWARD
2739 = plus_constant (argblock, current_function_pretend_args_size);
2741 = plus_constant (argblock, -current_function_pretend_args_size);
2743 stored_args_map = sbitmap_alloc (args_size.constant);
2744 sbitmap_zero (stored_args_map);
2747 /* If we have no actual push instructions, or shouldn't use them,
2748 make space for all args right now. */
2749 else if (adjusted_args_size.var != 0)
2751 if (old_stack_level == 0)
2753 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2754 old_pending_adj = pending_stack_adjust;
2755 pending_stack_adjust = 0;
2756 /* stack_arg_under_construction says whether a stack arg is
2757 being constructed at the old stack level. Pushing the stack
2758 gets a clean outgoing argument block. */
2759 old_stack_arg_under_construction = stack_arg_under_construction;
2760 stack_arg_under_construction = 0;
2762 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2766 /* Note that we must go through the motions of allocating an argument
2767 block even if the size is zero because we may be storing args
2768 in the area reserved for register arguments, which may be part of
2771 int needed = adjusted_args_size.constant;
2773 /* Store the maximum argument space used. It will be pushed by
2774 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2777 if (needed > current_function_outgoing_args_size)
2778 current_function_outgoing_args_size = needed;
2780 if (must_preallocate)
2782 if (ACCUMULATE_OUTGOING_ARGS)
2784 /* Since the stack pointer will never be pushed, it is
2785 possible for the evaluation of a parm to clobber
2786 something we have already written to the stack.
2787 Since most function calls on RISC machines do not use
2788 the stack, this is uncommon, but must work correctly.
2790 Therefore, we save any area of the stack that was already
2791 written and that we are using. Here we set up to do this
2792 by making a new stack usage map from the old one. The
2793 actual save will be done by store_one_arg.
2795 Another approach might be to try to reorder the argument
2796 evaluations to avoid this conflicting stack usage. */
2798 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2799 /* Since we will be writing into the entire argument area,
2800 the map must be allocated for its entire size, not just
2801 the part that is the responsibility of the caller. */
2802 needed += reg_parm_stack_space;
2805 #ifdef ARGS_GROW_DOWNWARD
2806 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2809 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2813 = (char *) alloca (highest_outgoing_arg_in_use);
2815 if (initial_highest_arg_in_use)
2816 memcpy (stack_usage_map, initial_stack_usage_map,
2817 initial_highest_arg_in_use);
2819 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2820 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2821 (highest_outgoing_arg_in_use
2822 - initial_highest_arg_in_use));
2825 /* The address of the outgoing argument list must not be
2826 copied to a register here, because argblock would be left
2827 pointing to the wrong place after the call to
2828 allocate_dynamic_stack_space below. */
2830 argblock = virtual_outgoing_args_rtx;
2834 if (inhibit_defer_pop == 0)
2836 /* Try to reuse some or all of the pending_stack_adjust
2837 to get this space. */
2839 = (combine_pending_stack_adjustment_and_call
2840 (unadjusted_args_size,
2841 &adjusted_args_size,
2842 preferred_unit_stack_boundary));
2844 /* combine_pending_stack_adjustment_and_call computes
2845 an adjustment before the arguments are allocated.
2846 Account for them and see whether or not the stack
2847 needs to go up or down. */
2848 needed = unadjusted_args_size - needed;
2852 /* We're releasing stack space. */
2853 /* ??? We can avoid any adjustment at all if we're
2854 already aligned. FIXME. */
2855 pending_stack_adjust = -needed;
2856 do_pending_stack_adjust ();
2860 /* We need to allocate space. We'll do that in
2861 push_block below. */
2862 pending_stack_adjust = 0;
2865 /* Special case this because overhead of `push_block' in
2866 this case is non-trivial. */
2868 argblock = virtual_outgoing_args_rtx;
2870 argblock = push_block (GEN_INT (needed), 0, 0);
2872 /* We only really need to call `copy_to_reg' in the case
2873 where push insns are going to be used to pass ARGBLOCK
2874 to a function call in ARGS. In that case, the stack
2875 pointer changes value from the allocation point to the
2876 call point, and hence the value of
2877 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2878 as well always do it. */
2879 argblock = copy_to_reg (argblock);
2881 /* The save/restore code in store_one_arg handles all
2882 cases except one: a constructor call (including a C
2883 function returning a BLKmode struct) to initialize
2885 if (stack_arg_under_construction)
2887 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2888 rtx push_size = GEN_INT (reg_parm_stack_space
2889 + adjusted_args_size.constant);
2891 rtx push_size = GEN_INT (adjusted_args_size.constant);
2893 if (old_stack_level == 0)
2895 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2897 old_pending_adj = pending_stack_adjust;
2898 pending_stack_adjust = 0;
2899 /* stack_arg_under_construction says whether a stack
2900 arg is being constructed at the old stack level.
2901 Pushing the stack gets a clean outgoing argument
2903 old_stack_arg_under_construction
2904 = stack_arg_under_construction;
2905 stack_arg_under_construction = 0;
2906 /* Make a new map for the new argument list. */
2907 stack_usage_map = (char *)
2908 alloca (highest_outgoing_arg_in_use);
2909 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2910 highest_outgoing_arg_in_use = 0;
2912 allocate_dynamic_stack_space (push_size, NULL_RTX,
2915 /* If argument evaluation might modify the stack pointer,
2916 copy the address of the argument list to a register. */
2917 for (i = 0; i < num_actuals; i++)
2918 if (args[i].pass_on_stack)
2920 argblock = copy_addr_to_reg (argblock);
2927 compute_argument_addresses (args, argblock, num_actuals);
2929 /* If we push args individually in reverse order, perform stack alignment
2930 before the first push (the last arg). */
2931 if (PUSH_ARGS_REVERSED && argblock == 0
2932 && adjusted_args_size.constant != unadjusted_args_size)
2934 /* When the stack adjustment is pending, we get better code
2935 by combining the adjustments. */
2936 if (pending_stack_adjust
2937 && ! (flags & ECF_LIBCALL_BLOCK)
2938 && ! inhibit_defer_pop)
2940 pending_stack_adjust
2941 = (combine_pending_stack_adjustment_and_call
2942 (unadjusted_args_size,
2943 &adjusted_args_size,
2944 preferred_unit_stack_boundary));
2945 do_pending_stack_adjust ();
2947 else if (argblock == 0)
2948 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2949 - unadjusted_args_size));
2951 /* Now that the stack is properly aligned, pops can't safely
2952 be deferred during the evaluation of the arguments. */
2955 funexp = rtx_for_function_call (fndecl, addr);
2957 /* Figure out the register where the value, if any, will come back. */
2959 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2960 && ! structure_value_addr)
2962 if (pcc_struct_value)
2963 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2964 fndecl, (pass == 0));
2966 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2969 /* Precompute all register parameters. It isn't safe to compute anything
2970 once we have started filling any specific hard regs. */
2971 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2973 #ifdef REG_PARM_STACK_SPACE
2974 /* Save the fixed argument area if it's part of the caller's frame and
2975 is clobbered by argument setup for this call. */
2976 if (ACCUMULATE_OUTGOING_ARGS && pass)
2977 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2978 &low_to_save, &high_to_save);
2981 /* Now store (and compute if necessary) all non-register parms.
2982 These come before register parms, since they can require block-moves,
2983 which could clobber the registers used for register parms.
2984 Parms which have partial registers are not stored here,
2985 but we do preallocate space here if they want that. */
2987 for (i = 0; i < num_actuals; i++)
2988 if (args[i].reg == 0 || args[i].pass_on_stack)
2990 rtx before_arg = get_last_insn ();
2992 if (store_one_arg (&args[i], argblock, flags,
2993 adjusted_args_size.var != 0,
2994 reg_parm_stack_space)
2996 && check_sibcall_argument_overlap (before_arg,
2998 sibcall_failure = 1;
3001 /* If we have a parm that is passed in registers but not in memory
3002 and whose alignment does not permit a direct copy into registers,
3003 make a group of pseudos that correspond to each register that we
3005 if (STRICT_ALIGNMENT)
3006 store_unaligned_arguments_into_pseudos (args, num_actuals);
3008 /* Now store any partially-in-registers parm.
3009 This is the last place a block-move can happen. */
3011 for (i = 0; i < num_actuals; i++)
3012 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3014 rtx before_arg = get_last_insn ();
3016 if (store_one_arg (&args[i], argblock, flags,
3017 adjusted_args_size.var != 0,
3018 reg_parm_stack_space)
3020 && check_sibcall_argument_overlap (before_arg,
3022 sibcall_failure = 1;
3025 /* If we pushed args in forward order, perform stack alignment
3026 after pushing the last arg. */
3027 if (!PUSH_ARGS_REVERSED && argblock == 0)
3028 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3029 - unadjusted_args_size));
3031 /* If register arguments require space on the stack and stack space
3032 was not preallocated, allocate stack space here for arguments
3033 passed in registers. */
3034 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3035 if (!ACCUMULATE_OUTGOING_ARGS
3036 && must_preallocate == 0 && reg_parm_stack_space > 0)
3037 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3040 /* Pass the function the address in which to return a
3042 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3044 emit_move_insn (struct_value_rtx,
3046 force_operand (structure_value_addr,
3049 if (GET_CODE (struct_value_rtx) == REG)
3050 use_reg (&call_fusage, struct_value_rtx);
3053 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3054 reg_parm_seen, pass == 0);
3056 load_register_parameters (args, num_actuals, &call_fusage, flags,
3057 pass == 0, &sibcall_failure);
3059 /* Perform postincrements before actually calling the function. */
3062 /* Save a pointer to the last insn before the call, so that we can
3063 later safely search backwards to find the CALL_INSN. */
3064 before_call = get_last_insn ();
3066 /* Set up next argument register. For sibling calls on machines
3067 with register windows this should be the incoming register. */
3068 #ifdef FUNCTION_INCOMING_ARG
3070 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3074 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3077 /* All arguments and registers used for the call must be set up by
3080 /* Stack must be properly aligned now. */
3081 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3084 /* Generate the actual call instruction. */
3085 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3086 adjusted_args_size.constant, struct_value_size,
3087 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3088 flags, & args_so_far);
3090 /* Verify that we've deallocated all the stack we used. */
3092 && old_stack_allocated != stack_pointer_delta - pending_stack_adjust)
3095 /* If call is cse'able, make appropriate pair of reg-notes around it.
3096 Test valreg so we don't crash; may safely ignore `const'
3097 if return type is void. Disable for PARALLEL return values, because
3098 we have no way to move such values into a pseudo register. */
3099 if (pass && (flags & ECF_LIBCALL_BLOCK))
3103 if (valreg == 0 || GET_CODE (valreg) == PARALLEL)
3105 insns = get_insns ();
3112 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3114 /* Mark the return value as a pointer if needed. */
3115 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3116 mark_reg_pointer (temp,
3117 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3119 /* Construct an "equal form" for the value which mentions all the
3120 arguments in order as well as the function name. */
3121 for (i = 0; i < num_actuals; i++)
3122 note = gen_rtx_EXPR_LIST (VOIDmode,
3123 args[i].initial_value, note);
3124 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3126 insns = get_insns ();
3129 if (flags & ECF_PURE)
3130 note = gen_rtx_EXPR_LIST (VOIDmode,
3131 gen_rtx_USE (VOIDmode,
3132 gen_rtx_MEM (BLKmode,
3133 gen_rtx_SCRATCH (VOIDmode))),
3136 emit_libcall_block (insns, temp, valreg, note);
3141 else if (pass && (flags & ECF_MALLOC))
3143 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3146 /* The return value from a malloc-like function is a pointer. */
3147 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3148 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3150 emit_move_insn (temp, valreg);
3152 /* The return value from a malloc-like function can not alias
3154 last = get_last_insn ();
3156 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3158 /* Write out the sequence. */
3159 insns = get_insns ();
3165 /* For calls to `setjmp', etc., inform flow.c it should complain
3166 if nonvolatile values are live. For functions that cannot return,
3167 inform flow that control does not fall through. */
3169 if ((flags & (ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3171 /* The barrier must be emitted
3172 immediately after the CALL_INSN. Some ports emit more
3173 than just a CALL_INSN above, so we must search for it here. */
3175 rtx last = get_last_insn ();
3176 while (GET_CODE (last) != CALL_INSN)
3178 last = PREV_INSN (last);
3179 /* There was no CALL_INSN? */
3180 if (last == before_call)
3184 emit_barrier_after (last);
3187 if (flags & ECF_LONGJMP)
3188 current_function_calls_longjmp = 1;
3190 /* If this function is returning into a memory location marked as
3191 readonly, it means it is initializing that location. But we normally
3192 treat functions as not clobbering such locations, so we need to
3193 specify that this one does. */
3194 if (target != 0 && GET_CODE (target) == MEM
3195 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
3196 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
3198 /* If value type not void, return an rtx for the value. */
3200 /* If there are cleanups to be called, don't use a hard reg as target.
3201 We need to double check this and see if it matters anymore. */
3202 if (any_pending_cleanups (1))
3204 if (target && REG_P (target)
3205 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3207 sibcall_failure = 1;
3210 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3212 target = const0_rtx;
3213 else if (structure_value_addr)
3215 if (target == 0 || GET_CODE (target) != MEM)
3218 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3219 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3220 structure_value_addr));
3221 set_mem_attributes (target, exp, 1);
3224 else if (pcc_struct_value)
3226 /* This is the special C++ case where we need to
3227 know what the true target was. We take care to
3228 never use this value more than once in one expression. */
3229 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3230 copy_to_reg (valreg));
3231 set_mem_attributes (target, exp, 1);
3233 /* Handle calls that return values in multiple non-contiguous locations.
3234 The Irix 6 ABI has examples of this. */
3235 else if (GET_CODE (valreg) == PARALLEL)
3239 /* This will only be assigned once, so it can be readonly. */
3240 tree nt = build_qualified_type (TREE_TYPE (exp),
3241 (TYPE_QUALS (TREE_TYPE (exp))
3242 | TYPE_QUAL_CONST));
3244 target = assign_temp (nt, 0, 1, 1);
3245 preserve_temp_slots (target);
3248 if (! rtx_equal_p (target, valreg))
3249 emit_group_store (target, valreg,
3250 int_size_in_bytes (TREE_TYPE (exp)));
3252 /* We can not support sibling calls for this case. */
3253 sibcall_failure = 1;
3256 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3257 && GET_MODE (target) == GET_MODE (valreg))
3259 /* TARGET and VALREG cannot be equal at this point because the
3260 latter would not have REG_FUNCTION_VALUE_P true, while the
3261 former would if it were referring to the same register.
3263 If they refer to the same register, this move will be a no-op,
3264 except when function inlining is being done. */
3265 emit_move_insn (target, valreg);
3267 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3269 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3271 /* We can not support sibling calls for this case. */
3272 sibcall_failure = 1;
3275 target = copy_to_reg (valreg);
3277 #ifdef PROMOTE_FUNCTION_RETURN
3278 /* If we promoted this return value, make the proper SUBREG. TARGET
3279 might be const0_rtx here, so be careful. */
3280 if (GET_CODE (target) == REG
3281 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3282 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3284 tree type = TREE_TYPE (exp);
3285 int unsignedp = TREE_UNSIGNED (type);
3288 /* If we don't promote as expected, something is wrong. */
3289 if (GET_MODE (target)
3290 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3293 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3294 && GET_MODE_SIZE (GET_MODE (target))
3295 > GET_MODE_SIZE (TYPE_MODE (type)))
3297 offset = GET_MODE_SIZE (GET_MODE (target))
3298 - GET_MODE_SIZE (TYPE_MODE (type));
3299 if (! BYTES_BIG_ENDIAN)
3300 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3301 else if (! WORDS_BIG_ENDIAN)
3302 offset %= UNITS_PER_WORD;
3304 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3305 SUBREG_PROMOTED_VAR_P (target) = 1;
3306 SUBREG_PROMOTED_UNSIGNED_SET (target, unsignedp);
3310 /* If size of args is variable or this was a constructor call for a stack
3311 argument, restore saved stack-pointer value. */
3313 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3315 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3316 pending_stack_adjust = old_pending_adj;
3317 stack_arg_under_construction = old_stack_arg_under_construction;
3318 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3319 stack_usage_map = initial_stack_usage_map;
3320 sibcall_failure = 1;
3322 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3324 #ifdef REG_PARM_STACK_SPACE
3326 restore_fixed_argument_area (save_area, argblock,
3327 high_to_save, low_to_save);
3330 /* If we saved any argument areas, restore them. */
3331 for (i = 0; i < num_actuals; i++)
3332 if (args[i].save_area)
3334 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3336 = gen_rtx_MEM (save_mode,
3337 memory_address (save_mode,
3338 XEXP (args[i].stack_slot, 0)));
3340 if (save_mode != BLKmode)
3341 emit_move_insn (stack_area, args[i].save_area);
3343 emit_block_move (stack_area, args[i].save_area,
3344 GEN_INT (args[i].size.constant),
3345 BLOCK_OP_CALL_PARM);
3348 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3349 stack_usage_map = initial_stack_usage_map;
3352 /* If this was alloca, record the new stack level for nonlocal gotos.
3353 Check for the handler slots since we might not have a save area
3354 for non-local gotos. */
3356 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3357 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3359 /* Free up storage we no longer need. */
3360 for (i = 0; i < num_actuals; ++i)
3361 if (args[i].aligned_regs)
3362 free (args[i].aligned_regs);
3366 /* Undo the fake expand_start_target_temps we did earlier. If
3367 there had been any cleanups created, we've already set
3369 expand_end_target_temps ();
3372 insns = get_insns ();
3377 tail_call_insns = insns;
3379 /* Restore the pending stack adjustment now that we have
3380 finished generating the sibling call sequence. */
3382 pending_stack_adjust = save_pending_stack_adjust;
3383 stack_pointer_delta = save_stack_pointer_delta;
3385 /* Prepare arg structure for next iteration. */
3386 for (i = 0; i < num_actuals; i++)
3389 args[i].aligned_regs = 0;
3393 sbitmap_free (stored_args_map);
3396 normal_call_insns = insns;
3398 /* If something prevents making this a sibling call,
3399 zero out the sequence. */
3400 if (sibcall_failure)
3401 tail_call_insns = NULL_RTX;
3404 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3405 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3406 can happen if the arguments to this function call an inline
3407 function who's expansion contains another CALL_PLACEHOLDER.
3409 If there are any C_Ps in any of these sequences, replace them
3410 with their normal call. */
3412 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3413 if (GET_CODE (insn) == CALL_INSN
3414 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3415 replace_call_placeholder (insn, sibcall_use_normal);
3417 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3418 if (GET_CODE (insn) == CALL_INSN
3419 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3420 replace_call_placeholder (insn, sibcall_use_normal);
3422 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3423 if (GET_CODE (insn) == CALL_INSN
3424 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3425 replace_call_placeholder (insn, sibcall_use_normal);
3427 /* If this was a potential tail recursion site, then emit a
3428 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3429 One of them will be selected later. */
3430 if (tail_recursion_insns || tail_call_insns)
3432 /* The tail recursion label must be kept around. We could expose
3433 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3434 and makes determining true tail recursion sites difficult.
3436 So we set LABEL_PRESERVE_P here, then clear it when we select
3437 one of the call sequences after rtl generation is complete. */
3438 if (tail_recursion_insns)
3439 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3440 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3442 tail_recursion_insns,
3443 tail_recursion_label));
3446 emit_insn (normal_call_insns);
3448 currently_expanding_call--;
3450 /* If this function returns with the stack pointer depressed, ensure
3451 this block saves and restores the stack pointer, show it was
3452 changed, and adjust for any outgoing arg space. */
3453 if (flags & ECF_SP_DEPRESSED)
3455 clear_pending_stack_adjust ();
3456 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3457 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3458 save_stack_pointer ();
3464 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3465 The RETVAL parameter specifies whether return value needs to be saved, other
3466 parameters are documented in the emit_library_call function below. */
3469 emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3473 enum libcall_type fn_type;
3474 enum machine_mode outmode;
3478 /* Total size in bytes of all the stack-parms scanned so far. */
3479 struct args_size args_size;
3480 /* Size of arguments before any adjustments (such as rounding). */
3481 struct args_size original_args_size;
3486 struct args_size alignment_pad;
3488 CUMULATIVE_ARGS args_so_far;
3492 enum machine_mode mode;
3495 struct args_size offset;
3496 struct args_size size;
3500 int old_inhibit_defer_pop = inhibit_defer_pop;
3501 rtx call_fusage = 0;
3504 int pcc_struct_value = 0;
3505 int struct_value_size = 0;
3507 int reg_parm_stack_space = 0;
3510 tree tfom; /* type_for_mode (outmode, 0) */
3512 #ifdef REG_PARM_STACK_SPACE
3513 /* Define the boundary of the register parm stack space that needs to be
3515 int low_to_save, high_to_save;
3516 rtx save_area = 0; /* Place that it is saved. */
3519 /* Size of the stack reserved for parameter registers. */
3520 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3521 char *initial_stack_usage_map = stack_usage_map;
3523 #ifdef REG_PARM_STACK_SPACE
3524 #ifdef MAYBE_REG_PARM_STACK_SPACE
3525 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3527 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3531 /* By default, library functions can not throw. */
3532 flags = ECF_NOTHROW;
3544 case LCT_CONST_MAKE_BLOCK:
3545 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
3547 case LCT_PURE_MAKE_BLOCK:
3548 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
3551 flags |= ECF_NORETURN;
3554 flags = ECF_NORETURN;
3556 case LCT_ALWAYS_RETURN:
3557 flags = ECF_ALWAYS_RETURN;
3559 case LCT_RETURNS_TWICE:
3560 flags = ECF_RETURNS_TWICE;
3565 /* Ensure current function's preferred stack boundary is at least
3567 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3568 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3570 /* If this kind of value comes back in memory,
3571 decide where in memory it should come back. */
3572 if (outmode != VOIDmode)
3574 tfom = (*lang_hooks.types.type_for_mode) (outmode, 0);
3575 if (aggregate_value_p (tfom))
3577 #ifdef PCC_STATIC_STRUCT_RETURN
3579 = hard_function_value (build_pointer_type (tfom), 0, 0);
3580 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3581 pcc_struct_value = 1;
3583 value = gen_reg_rtx (outmode);
3584 #else /* not PCC_STATIC_STRUCT_RETURN */
3585 struct_value_size = GET_MODE_SIZE (outmode);
3586 if (value != 0 && GET_CODE (value) == MEM)
3589 mem_value = assign_temp (tfom, 0, 1, 1);
3591 /* This call returns a big structure. */
3592 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3596 tfom = void_type_node;
3598 /* ??? Unfinished: must pass the memory address as an argument. */
3600 /* Copy all the libcall-arguments out of the varargs data
3601 and into a vector ARGVEC.
3603 Compute how to pass each argument. We only support a very small subset
3604 of the full argument passing conventions to limit complexity here since
3605 library functions shouldn't have many args. */
3607 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3608 memset ((char *) argvec, 0, (nargs + 1) * sizeof (struct arg));
3610 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3611 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3613 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3616 args_size.constant = 0;
3621 /* Now we are about to start emitting insns that can be deleted
3622 if a libcall is deleted. */
3623 if (flags & ECF_LIBCALL_BLOCK)
3628 /* If there's a structure value address to be passed,
3629 either pass it in the special place, or pass it as an extra argument. */
3630 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3632 rtx addr = XEXP (mem_value, 0);
3635 /* Make sure it is a reasonable operand for a move or push insn. */
3636 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3637 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3638 addr = force_operand (addr, NULL_RTX);
3640 argvec[count].value = addr;
3641 argvec[count].mode = Pmode;
3642 argvec[count].partial = 0;
3644 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3645 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3646 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3650 locate_and_pad_parm (Pmode, NULL_TREE,
3651 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3654 argvec[count].reg != 0,
3656 NULL_TREE, &args_size, &argvec[count].offset,
3657 &argvec[count].size, &alignment_pad);
3659 if (argvec[count].reg == 0 || argvec[count].partial != 0
3660 || reg_parm_stack_space > 0)
3661 args_size.constant += argvec[count].size.constant;
3663 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3668 for (; count < nargs; count++)
3670 rtx val = va_arg (p, rtx);
3671 enum machine_mode mode = va_arg (p, enum machine_mode);
3673 /* We cannot convert the arg value to the mode the library wants here;
3674 must do it earlier where we know the signedness of the arg. */
3676 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3679 /* On some machines, there's no way to pass a float to a library fcn.
3680 Pass it as a double instead. */
3681 #ifdef LIBGCC_NEEDS_DOUBLE
3682 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3683 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3686 /* There's no need to call protect_from_queue, because
3687 either emit_move_insn or emit_push_insn will do that. */
3689 /* Make sure it is a reasonable operand for a move or push insn. */
3690 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3691 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3692 val = force_operand (val, NULL_RTX);
3694 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3695 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3699 #ifdef FUNCTION_ARG_CALLEE_COPIES
3700 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3705 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3706 functions, so we have to pretend this isn't such a function. */
3707 if (flags & ECF_LIBCALL_BLOCK)
3709 rtx insns = get_insns ();
3713 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3715 /* If this was a CONST function, it is now PURE since
3716 it now reads memory. */
3717 if (flags & ECF_CONST)
3719 flags &= ~ECF_CONST;
3723 if (GET_MODE (val) == MEM && ! must_copy)
3727 slot = assign_temp ((*lang_hooks.types.type_for_mode) (mode, 0),
3729 emit_move_insn (slot, val);
3733 tree type = (*lang_hooks.types.type_for_mode) (mode, 0);
3736 = gen_rtx_MEM (mode,
3737 expand_expr (build1 (ADDR_EXPR,
3738 build_pointer_type (type),
3739 make_tree (type, val)),
3740 NULL_RTX, VOIDmode, 0));
3743 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3744 gen_rtx_USE (VOIDmode, slot),
3747 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3748 gen_rtx_CLOBBER (VOIDmode,
3753 val = force_operand (XEXP (slot, 0), NULL_RTX);
3757 argvec[count].value = val;
3758 argvec[count].mode = mode;
3760 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3762 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3763 argvec[count].partial
3764 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3766 argvec[count].partial = 0;
3769 locate_and_pad_parm (mode, NULL_TREE,
3770 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3773 argvec[count].reg != 0,
3775 NULL_TREE, &args_size, &argvec[count].offset,
3776 &argvec[count].size, &alignment_pad);
3778 if (argvec[count].size.var)
3781 if (reg_parm_stack_space == 0 && argvec[count].partial)
3782 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3784 if (argvec[count].reg == 0 || argvec[count].partial != 0
3785 || reg_parm_stack_space > 0)
3786 args_size.constant += argvec[count].size.constant;
3788 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3791 #ifdef FINAL_REG_PARM_STACK_SPACE
3792 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3795 /* If this machine requires an external definition for library
3796 functions, write one out. */
3797 assemble_external_libcall (fun);
3799 original_args_size = args_size;
3800 args_size.constant = (((args_size.constant
3801 + stack_pointer_delta
3805 - stack_pointer_delta);
3807 args_size.constant = MAX (args_size.constant,
3808 reg_parm_stack_space);
3810 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3811 args_size.constant -= reg_parm_stack_space;
3814 if (args_size.constant > current_function_outgoing_args_size)
3815 current_function_outgoing_args_size = args_size.constant;
3817 if (ACCUMULATE_OUTGOING_ARGS)
3819 /* Since the stack pointer will never be pushed, it is possible for
3820 the evaluation of a parm to clobber something we have already
3821 written to the stack. Since most function calls on RISC machines
3822 do not use the stack, this is uncommon, but must work correctly.
3824 Therefore, we save any area of the stack that was already written
3825 and that we are using. Here we set up to do this by making a new
3826 stack usage map from the old one.
3828 Another approach might be to try to reorder the argument
3829 evaluations to avoid this conflicting stack usage. */
3831 needed = args_size.constant;
3833 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3834 /* Since we will be writing into the entire argument area, the
3835 map must be allocated for its entire size, not just the part that
3836 is the responsibility of the caller. */
3837 needed += reg_parm_stack_space;
3840 #ifdef ARGS_GROW_DOWNWARD
3841 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3844 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3847 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3849 if (initial_highest_arg_in_use)
3850 memcpy (stack_usage_map, initial_stack_usage_map,
3851 initial_highest_arg_in_use);
3853 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3854 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3855 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3858 /* We must be careful to use virtual regs before they're instantiated,
3859 and real regs afterwards. Loop optimization, for example, can create
3860 new libcalls after we've instantiated the virtual regs, and if we
3861 use virtuals anyway, they won't match the rtl patterns. */
3863 if (virtuals_instantiated)
3864 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
3866 argblock = virtual_outgoing_args_rtx;
3871 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3874 /* If we push args individually in reverse order, perform stack alignment
3875 before the first push (the last arg). */
3876 if (argblock == 0 && PUSH_ARGS_REVERSED)
3877 anti_adjust_stack (GEN_INT (args_size.constant
3878 - original_args_size.constant));
3880 if (PUSH_ARGS_REVERSED)
3891 #ifdef REG_PARM_STACK_SPACE
3892 if (ACCUMULATE_OUTGOING_ARGS)
3894 /* The argument list is the property of the called routine and it
3895 may clobber it. If the fixed area has been used for previous
3896 parameters, we must save and restore it. */
3897 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3898 &low_to_save, &high_to_save);
3902 /* Push the args that need to be pushed. */
3904 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3905 are to be pushed. */
3906 for (count = 0; count < nargs; count++, argnum += inc)
3908 enum machine_mode mode = argvec[argnum].mode;
3909 rtx val = argvec[argnum].value;
3910 rtx reg = argvec[argnum].reg;
3911 int partial = argvec[argnum].partial;
3912 int lower_bound = 0, upper_bound = 0, i;
3914 if (! (reg != 0 && partial == 0))
3916 if (ACCUMULATE_OUTGOING_ARGS)
3918 /* If this is being stored into a pre-allocated, fixed-size,
3919 stack area, save any previous data at that location. */
3921 #ifdef ARGS_GROW_DOWNWARD
3922 /* stack_slot is negative, but we want to index stack_usage_map
3923 with positive values. */
3924 upper_bound = -argvec[argnum].offset.constant + 1;
3925 lower_bound = upper_bound - argvec[argnum].size.constant;
3927 lower_bound = argvec[argnum].offset.constant;
3928 upper_bound = lower_bound + argvec[argnum].size.constant;
3932 /* Don't worry about things in the fixed argument area;
3933 it has already been saved. */
3934 if (i < reg_parm_stack_space)
3935 i = reg_parm_stack_space;
3936 while (i < upper_bound && stack_usage_map[i] == 0)
3939 if (i < upper_bound)
3941 /* We need to make a save area. See what mode we can make
3943 enum machine_mode save_mode
3944 = mode_for_size (argvec[argnum].size.constant
3952 plus_constant (argblock,
3953 argvec[argnum].offset.constant)));
3954 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3956 emit_move_insn (argvec[argnum].save_area, stack_area);
3960 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, PARM_BOUNDARY,
3961 partial, reg, 0, argblock,
3962 GEN_INT (argvec[argnum].offset.constant),
3963 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3965 /* Now mark the segment we just used. */
3966 if (ACCUMULATE_OUTGOING_ARGS)
3967 for (i = lower_bound; i < upper_bound; i++)
3968 stack_usage_map[i] = 1;
3974 /* If we pushed args in forward order, perform stack alignment
3975 after pushing the last arg. */
3976 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3977 anti_adjust_stack (GEN_INT (args_size.constant
3978 - original_args_size.constant));
3980 if (PUSH_ARGS_REVERSED)
3985 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0, 0);
3987 /* Now load any reg parms into their regs. */
3989 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3990 are to be pushed. */
3991 for (count = 0; count < nargs; count++, argnum += inc)
3993 rtx val = argvec[argnum].value;
3994 rtx reg = argvec[argnum].reg;
3995 int partial = argvec[argnum].partial;
3997 /* Handle calls that pass values in multiple non-contiguous
3998 locations. The PA64 has examples of this for library calls. */
3999 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4000 emit_group_load (reg, val, GET_MODE_SIZE (GET_MODE (val)));
4001 else if (reg != 0 && partial == 0)
4002 emit_move_insn (reg, val);
4007 /* Any regs containing parms remain in use through the call. */
4008 for (count = 0; count < nargs; count++)
4010 rtx reg = argvec[count].reg;
4011 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4012 use_group_regs (&call_fusage, reg);
4014 use_reg (&call_fusage, reg);
4017 /* Pass the function the address in which to return a structure value. */
4018 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
4020 emit_move_insn (struct_value_rtx,
4022 force_operand (XEXP (mem_value, 0),
4024 if (GET_CODE (struct_value_rtx) == REG)
4025 use_reg (&call_fusage, struct_value_rtx);
4028 /* Don't allow popping to be deferred, since then
4029 cse'ing of library calls could delete a call and leave the pop. */
4031 valreg = (mem_value == 0 && outmode != VOIDmode
4032 ? hard_libcall_value (outmode) : NULL_RTX);
4034 /* Stack must be properly aligned now. */
4035 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4038 before_call = get_last_insn ();
4040 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4041 will set inhibit_defer_pop to that value. */
4042 /* The return type is needed to decide how many bytes the function pops.
4043 Signedness plays no role in that, so for simplicity, we pretend it's
4044 always signed. We also assume that the list of arguments passed has
4045 no impact, so we pretend it is unknown. */
4048 get_identifier (XSTR (orgfun, 0)),
4049 build_function_type (tfom, NULL_TREE),
4050 original_args_size.constant, args_size.constant,
4052 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4054 old_inhibit_defer_pop + 1, call_fusage, flags, & args_so_far);
4056 /* For calls to `setjmp', etc., inform flow.c it should complain
4057 if nonvolatile values are live. For functions that cannot return,
4058 inform flow that control does not fall through. */
4060 if (flags & (ECF_NORETURN | ECF_LONGJMP))
4062 /* The barrier note must be emitted
4063 immediately after the CALL_INSN. Some ports emit more than
4064 just a CALL_INSN above, so we must search for it here. */
4066 rtx last = get_last_insn ();
4067 while (GET_CODE (last) != CALL_INSN)
4069 last = PREV_INSN (last);
4070 /* There was no CALL_INSN? */
4071 if (last == before_call)
4075 emit_barrier_after (last);
4078 /* Now restore inhibit_defer_pop to its actual original value. */
4081 /* If call is cse'able, make appropriate pair of reg-notes around it.
4082 Test valreg so we don't crash; may safely ignore `const'
4083 if return type is void. Disable for PARALLEL return values, because
4084 we have no way to move such values into a pseudo register. */
4085 if (flags & ECF_LIBCALL_BLOCK)
4091 insns = get_insns ();
4101 if (GET_CODE (valreg) == PARALLEL)
4103 temp = gen_reg_rtx (outmode);
4104 emit_group_store (temp, valreg, outmode);
4108 temp = gen_reg_rtx (GET_MODE (valreg));
4110 /* Construct an "equal form" for the value which mentions all the
4111 arguments in order as well as the function name. */
4112 for (i = 0; i < nargs; i++)
4113 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4114 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4116 insns = get_insns ();
4119 if (flags & ECF_PURE)
4120 note = gen_rtx_EXPR_LIST (VOIDmode,
4121 gen_rtx_USE (VOIDmode,
4122 gen_rtx_MEM (BLKmode,
4123 gen_rtx_SCRATCH (VOIDmode))),
4126 emit_libcall_block (insns, temp, valreg, note);
4133 /* Copy the value to the right place. */
4134 if (outmode != VOIDmode && retval)
4140 if (value != mem_value)
4141 emit_move_insn (value, mem_value);
4143 else if (GET_CODE (valreg) == PARALLEL)
4146 value = gen_reg_rtx (outmode);
4147 emit_group_store (value, valreg, outmode);
4149 else if (value != 0)
4150 emit_move_insn (value, valreg);
4155 if (ACCUMULATE_OUTGOING_ARGS)
4157 #ifdef REG_PARM_STACK_SPACE
4159 restore_fixed_argument_area (save_area, argblock,
4160 high_to_save, low_to_save);
4163 /* If we saved any argument areas, restore them. */
4164 for (count = 0; count < nargs; count++)
4165 if (argvec[count].save_area)
4167 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4169 = gen_rtx_MEM (save_mode,
4172 plus_constant (argblock,
4173 argvec[count].offset.constant)));
4175 emit_move_insn (stack_area, argvec[count].save_area);
4178 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4179 stack_usage_map = initial_stack_usage_map;
4186 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4187 (emitting the queue unless NO_QUEUE is nonzero),
4188 for a value of mode OUTMODE,
4189 with NARGS different arguments, passed as alternating rtx values
4190 and machine_modes to convert them to.
4191 The rtx values should have been passed through protect_from_queue already.
4193 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4194 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4195 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4196 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4197 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4198 or other LCT_ value for other types of library calls. */
4201 emit_library_call VPARAMS((rtx orgfun, enum libcall_type fn_type,
4202 enum machine_mode outmode, int nargs, ...))
4205 VA_FIXEDARG (p, rtx, orgfun);
4206 VA_FIXEDARG (p, int, fn_type);
4207 VA_FIXEDARG (p, enum machine_mode, outmode);
4208 VA_FIXEDARG (p, int, nargs);
4210 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4215 /* Like emit_library_call except that an extra argument, VALUE,
4216 comes second and says where to store the result.
4217 (If VALUE is zero, this function chooses a convenient way
4218 to return the value.
4220 This function returns an rtx for where the value is to be found.
4221 If VALUE is nonzero, VALUE is returned. */
4224 emit_library_call_value VPARAMS((rtx orgfun, rtx value,
4225 enum libcall_type fn_type,
4226 enum machine_mode outmode, int nargs, ...))
4231 VA_FIXEDARG (p, rtx, orgfun);
4232 VA_FIXEDARG (p, rtx, value);
4233 VA_FIXEDARG (p, int, fn_type);
4234 VA_FIXEDARG (p, enum machine_mode, outmode);
4235 VA_FIXEDARG (p, int, nargs);
4237 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4245 /* Store a single argument for a function call
4246 into the register or memory area where it must be passed.
4247 *ARG describes the argument value and where to pass it.
4249 ARGBLOCK is the address of the stack-block for all the arguments,
4250 or 0 on a machine where arguments are pushed individually.
4252 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4253 so must be careful about how the stack is used.
4255 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4256 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4257 that we need not worry about saving and restoring the stack.
4259 FNDECL is the declaration of the function we are calling.
4261 Return nonzero if this arg should cause sibcall failure,
4265 store_one_arg (arg, argblock, flags, variable_size, reg_parm_stack_space)
4266 struct arg_data *arg;
4269 int variable_size ATTRIBUTE_UNUSED;
4270 int reg_parm_stack_space;
4272 tree pval = arg->tree_value;
4276 int i, lower_bound = 0, upper_bound = 0;
4277 int sibcall_failure = 0;
4279 if (TREE_CODE (pval) == ERROR_MARK)
4282 /* Push a new temporary level for any temporaries we make for
4286 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4288 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4289 save any previous data at that location. */
4290 if (argblock && ! variable_size && arg->stack)
4292 #ifdef ARGS_GROW_DOWNWARD
4293 /* stack_slot is negative, but we want to index stack_usage_map
4294 with positive values. */
4295 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4296 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4300 lower_bound = upper_bound - arg->size.constant;
4302 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4303 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4307 upper_bound = lower_bound + arg->size.constant;
4311 /* Don't worry about things in the fixed argument area;
4312 it has already been saved. */
4313 if (i < reg_parm_stack_space)
4314 i = reg_parm_stack_space;
4315 while (i < upper_bound && stack_usage_map[i] == 0)
4318 if (i < upper_bound)
4320 /* We need to make a save area. See what mode we can make it. */
4321 enum machine_mode save_mode
4322 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
4324 = gen_rtx_MEM (save_mode,
4325 memory_address (save_mode,
4326 XEXP (arg->stack_slot, 0)));
4328 if (save_mode == BLKmode)
4330 tree ot = TREE_TYPE (arg->tree_value);
4331 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4332 | TYPE_QUAL_CONST));
4334 arg->save_area = assign_temp (nt, 0, 1, 1);
4335 preserve_temp_slots (arg->save_area);
4336 emit_block_move (validize_mem (arg->save_area), stack_area,
4337 expr_size (arg->tree_value),
4338 BLOCK_OP_CALL_PARM);
4342 arg->save_area = gen_reg_rtx (save_mode);
4343 emit_move_insn (arg->save_area, stack_area);
4349 /* If this isn't going to be placed on both the stack and in registers,
4350 set up the register and number of words. */
4351 if (! arg->pass_on_stack)
4353 if (flags & ECF_SIBCALL)
4354 reg = arg->tail_call_reg;
4357 partial = arg->partial;
4360 if (reg != 0 && partial == 0)
4361 /* Being passed entirely in a register. We shouldn't be called in
4365 /* If this arg needs special alignment, don't load the registers
4367 if (arg->n_aligned_regs != 0)
4370 /* If this is being passed partially in a register, we can't evaluate
4371 it directly into its stack slot. Otherwise, we can. */
4372 if (arg->value == 0)
4374 /* stack_arg_under_construction is nonzero if a function argument is
4375 being evaluated directly into the outgoing argument list and
4376 expand_call must take special action to preserve the argument list
4377 if it is called recursively.
4379 For scalar function arguments stack_usage_map is sufficient to
4380 determine which stack slots must be saved and restored. Scalar
4381 arguments in general have pass_on_stack == 0.
4383 If this argument is initialized by a function which takes the
4384 address of the argument (a C++ constructor or a C function
4385 returning a BLKmode structure), then stack_usage_map is
4386 insufficient and expand_call must push the stack around the
4387 function call. Such arguments have pass_on_stack == 1.
4389 Note that it is always safe to set stack_arg_under_construction,
4390 but this generates suboptimal code if set when not needed. */
4392 if (arg->pass_on_stack)
4393 stack_arg_under_construction++;
4395 arg->value = expand_expr (pval,
4397 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4398 ? NULL_RTX : arg->stack,
4399 VOIDmode, EXPAND_STACK_PARM);
4401 /* If we are promoting object (or for any other reason) the mode
4402 doesn't agree, convert the mode. */
4404 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4405 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4406 arg->value, arg->unsignedp);
4408 if (arg->pass_on_stack)
4409 stack_arg_under_construction--;
4412 /* Don't allow anything left on stack from computation
4413 of argument to alloca. */
4414 if (flags & ECF_MAY_BE_ALLOCA)
4415 do_pending_stack_adjust ();
4417 if (arg->value == arg->stack)
4418 /* If the value is already in the stack slot, we are done. */
4420 else if (arg->mode != BLKmode)
4424 /* Argument is a scalar, not entirely passed in registers.
4425 (If part is passed in registers, arg->partial says how much
4426 and emit_push_insn will take care of putting it there.)
4428 Push it, and if its size is less than the
4429 amount of space allocated to it,
4430 also bump stack pointer by the additional space.
4431 Note that in C the default argument promotions
4432 will prevent such mismatches. */
4434 size = GET_MODE_SIZE (arg->mode);
4435 /* Compute how much space the push instruction will push.
4436 On many machines, pushing a byte will advance the stack
4437 pointer by a halfword. */
4438 #ifdef PUSH_ROUNDING
4439 size = PUSH_ROUNDING (size);
4443 /* Compute how much space the argument should get:
4444 round up to a multiple of the alignment for arguments. */
4445 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4446 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4447 / (PARM_BOUNDARY / BITS_PER_UNIT))
4448 * (PARM_BOUNDARY / BITS_PER_UNIT));
4450 /* This isn't already where we want it on the stack, so put it there.
4451 This can either be done with push or copy insns. */
4452 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4453 PARM_BOUNDARY, partial, reg, used - size, argblock,
4454 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4455 ARGS_SIZE_RTX (arg->alignment_pad));
4457 /* Unless this is a partially-in-register argument, the argument is now
4460 arg->value = arg->stack;
4464 /* BLKmode, at least partly to be pushed. */
4466 unsigned int parm_align;
4470 /* Pushing a nonscalar.
4471 If part is passed in registers, PARTIAL says how much
4472 and emit_push_insn will take care of putting it there. */
4474 /* Round its size up to a multiple
4475 of the allocation unit for arguments. */
4477 if (arg->size.var != 0)
4480 size_rtx = ARGS_SIZE_RTX (arg->size);
4484 /* PUSH_ROUNDING has no effect on us, because
4485 emit_push_insn for BLKmode is careful to avoid it. */
4486 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4487 + partial * UNITS_PER_WORD);
4488 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4489 NULL_RTX, TYPE_MODE (sizetype), 0);
4492 /* Some types will require stricter alignment, which will be
4493 provided for elsewhere in argument layout. */
4494 parm_align = MAX (PARM_BOUNDARY, TYPE_ALIGN (TREE_TYPE (pval)));
4496 /* When an argument is padded down, the block is aligned to
4497 PARM_BOUNDARY, but the actual argument isn't. */
4498 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4501 parm_align = BITS_PER_UNIT;
4504 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4505 parm_align = MIN (parm_align, excess_align);
4509 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4511 /* emit_push_insn might not work properly if arg->value and
4512 argblock + arg->offset areas overlap. */
4516 if (XEXP (x, 0) == current_function_internal_arg_pointer
4517 || (GET_CODE (XEXP (x, 0)) == PLUS
4518 && XEXP (XEXP (x, 0), 0) ==
4519 current_function_internal_arg_pointer
4520 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4522 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4523 i = INTVAL (XEXP (XEXP (x, 0), 1));
4525 /* expand_call should ensure this */
4526 if (arg->offset.var || GET_CODE (size_rtx) != CONST_INT)
4529 if (arg->offset.constant > i)
4531 if (arg->offset.constant < i + INTVAL (size_rtx))
4532 sibcall_failure = 1;
4534 else if (arg->offset.constant < i)
4536 if (i < arg->offset.constant + INTVAL (size_rtx))
4537 sibcall_failure = 1;
4542 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4543 parm_align, partial, reg, excess, argblock,
4544 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4545 ARGS_SIZE_RTX (arg->alignment_pad));
4547 /* Unless this is a partially-in-register argument, the argument is now
4550 ??? Unlike the case above, in which we want the actual
4551 address of the data, so that we can load it directly into a
4552 register, here we want the address of the stack slot, so that
4553 it's properly aligned for word-by-word copying or something
4554 like that. It's not clear that this is always correct. */
4556 arg->value = arg->stack_slot;
4559 /* Mark all slots this store used. */
4560 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
4561 && argblock && ! variable_size && arg->stack)
4562 for (i = lower_bound; i < upper_bound; i++)
4563 stack_usage_map[i] = 1;
4565 /* Once we have pushed something, pops can't safely
4566 be deferred during the rest of the arguments. */
4569 /* ANSI doesn't require a sequence point here,
4570 but PCC has one, so this will avoid some problems. */
4573 /* Free any temporary slots made in processing this argument. Show
4574 that we might have taken the address of something and pushed that
4576 preserve_temp_slots (NULL_RTX);
4580 return sibcall_failure;
4583 /* Nonzero if we do not know how to pass TYPE solely in registers.
4584 We cannot do so in the following cases:
4586 - if the type has variable size
4587 - if the type is marked as addressable (it is required to be constructed
4589 - if the padding and mode of the type is such that a copy into a register
4590 would put it into the wrong part of the register.
4592 Which padding can't be supported depends on the byte endianness.
4594 A value in a register is implicitly padded at the most significant end.
4595 On a big-endian machine, that is the lower end in memory.
4596 So a value padded in memory at the upper end can't go in a register.
4597 For a little-endian machine, the reverse is true. */
4600 default_must_pass_in_stack (mode, type)
4601 enum machine_mode mode;
4607 /* If the type has variable size... */
4608 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4611 /* If the type is marked as addressable (it is required
4612 to be constructed into the stack)... */
4613 if (TREE_ADDRESSABLE (type))
4616 /* If the padding and mode of the type is such that a copy into
4617 a register would put it into the wrong part of the register. */
4619 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
4620 && (FUNCTION_ARG_PADDING (mode, type)
4621 == (BYTES_BIG_ENDIAN ? upward : downward)))