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
36 #include "langhooks.h"
40 #if !defined FUNCTION_OK_FOR_SIBCALL
41 #define FUNCTION_OK_FOR_SIBCALL(DECL) 1
44 /* Decide whether a function's arguments should be processed
45 from first to last or from last to first.
47 They should if the stack and args grow in opposite directions, but
48 only if we have push insns. */
52 #ifndef PUSH_ARGS_REVERSED
53 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
54 #define PUSH_ARGS_REVERSED PUSH_ARGS
60 #ifndef PUSH_ARGS_REVERSED
61 #define PUSH_ARGS_REVERSED 0
64 #ifndef STACK_POINTER_OFFSET
65 #define STACK_POINTER_OFFSET 0
68 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
69 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
71 /* Data structure and subroutines used within expand_call. */
75 /* Tree node for this argument. */
77 /* Mode for value; TYPE_MODE unless promoted. */
78 enum machine_mode mode;
79 /* Current RTL value for argument, or 0 if it isn't precomputed. */
81 /* Initially-compute RTL value for argument; only for const functions. */
83 /* Register to pass this argument in, 0 if passed on stack, or an
84 PARALLEL if the arg is to be copied into multiple non-contiguous
87 /* Register to pass this argument in when generating tail call sequence.
88 This is not the same register as for normal calls on machines with
91 /* If REG was promoted from the actual mode of the argument expression,
92 indicates whether the promotion is sign- or zero-extended. */
94 /* Number of registers to use. 0 means put the whole arg in registers.
95 Also 0 if not passed in registers. */
97 /* Nonzero if argument must be passed on stack.
98 Note that some arguments may be passed on the stack
99 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
100 pass_on_stack identifies arguments that *cannot* go in registers. */
102 /* Offset of this argument from beginning of stack-args. */
103 struct args_size offset;
104 /* Similar, but offset to the start of the stack slot. Different from
105 OFFSET if this arg pads downward. */
106 struct args_size slot_offset;
107 /* Size of this argument on the stack, rounded up for any padding it gets,
108 parts of the argument passed in registers do not count.
109 If REG_PARM_STACK_SPACE is defined, then register parms
110 are counted here as well. */
111 struct args_size size;
112 /* Location on the stack at which parameter should be stored. The store
113 has already been done if STACK == VALUE. */
115 /* Location on the stack of the start of this argument slot. This can
116 differ from STACK if this arg pads downward. This location is known
117 to be aligned to FUNCTION_ARG_BOUNDARY. */
119 /* Place that this stack area has been saved, if needed. */
121 /* If an argument's alignment does not permit direct copying into registers,
122 copy in smaller-sized pieces into pseudos. These are stored in a
123 block pointed to by this field. The next field says how many
124 word-sized pseudos we made. */
127 /* The amount that the stack pointer needs to be adjusted to
128 force alignment for the next argument. */
129 struct args_size alignment_pad;
132 /* A vector of one char per byte of stack space. A byte if nonzero if
133 the corresponding stack location has been used.
134 This vector is used to prevent a function call within an argument from
135 clobbering any stack already set up. */
136 static char *stack_usage_map;
138 /* Size of STACK_USAGE_MAP. */
139 static int highest_outgoing_arg_in_use;
141 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
142 stack location's tail call argument has been already stored into the stack.
143 This bitmap is used to prevent sibling call optimization if function tries
144 to use parent's incoming argument slots when they have been already
145 overwritten with tail call arguments. */
146 static sbitmap stored_args_map;
148 /* stack_arg_under_construction is nonzero when an argument may be
149 initialized with a constructor call (including a C function that
150 returns a BLKmode struct) and expand_call must take special action
151 to make sure the object being constructed does not overlap the
152 argument list for the constructor call. */
153 int stack_arg_under_construction;
155 static int calls_function PARAMS ((tree, int));
156 static int calls_function_1 PARAMS ((tree, int));
158 /* Nonzero if this is a call to a `const' function. */
160 /* Nonzero if this is a call to a `volatile' function. */
161 #define ECF_NORETURN 2
162 /* Nonzero if this is a call to malloc or a related function. */
164 /* Nonzero if it is plausible that this is a call to alloca. */
165 #define ECF_MAY_BE_ALLOCA 8
166 /* Nonzero if this is a call to a function that won't throw an exception. */
167 #define ECF_NOTHROW 16
168 /* Nonzero if this is a call to setjmp or a related function. */
169 #define ECF_RETURNS_TWICE 32
170 /* Nonzero if this is a call to `longjmp'. */
171 #define ECF_LONGJMP 64
172 /* Nonzero if this is a syscall that makes a new process in the image of
174 #define ECF_FORK_OR_EXEC 128
175 #define ECF_SIBCALL 256
176 /* Nonzero if this is a call to "pure" function (like const function,
177 but may read memory. */
179 /* Nonzero if this is a call to a function that returns with the stack
180 pointer depressed. */
181 #define ECF_SP_DEPRESSED 1024
182 /* Nonzero if this call is known to always return. */
183 #define ECF_ALWAYS_RETURN 2048
184 /* Create libcall block around the call. */
185 #define ECF_LIBCALL_BLOCK 4096
187 static void emit_call_1 PARAMS ((rtx, tree, tree, HOST_WIDE_INT,
188 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
191 static void precompute_register_parameters PARAMS ((int,
194 static int store_one_arg PARAMS ((struct arg_data *, rtx, int, int,
196 static void store_unaligned_arguments_into_pseudos PARAMS ((struct arg_data *,
198 static int finalize_must_preallocate PARAMS ((int, int,
200 struct args_size *));
201 static void precompute_arguments PARAMS ((int, int,
203 static int compute_argument_block_size PARAMS ((int,
206 static void initialize_argument_information PARAMS ((int,
213 static void compute_argument_addresses PARAMS ((struct arg_data *,
215 static rtx rtx_for_function_call PARAMS ((tree, tree));
216 static void load_register_parameters PARAMS ((struct arg_data *,
218 static rtx emit_library_call_value_1 PARAMS ((int, rtx, rtx,
222 static int special_function_p PARAMS ((tree, int));
223 static int flags_from_decl_or_type PARAMS ((tree));
224 static rtx try_to_integrate PARAMS ((tree, tree, rtx,
226 static int check_sibcall_argument_overlap_1 PARAMS ((rtx));
227 static int check_sibcall_argument_overlap PARAMS ((rtx, struct arg_data *));
229 static int combine_pending_stack_adjustment_and_call
230 PARAMS ((int, struct args_size *, int));
231 static tree fix_unsafe_tree PARAMS ((tree));
233 #ifdef REG_PARM_STACK_SPACE
234 static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
235 static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
238 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
241 If WHICH is 0, return 1 if EXP contains a call to any function.
242 Actually, we only need return 1 if evaluating EXP would require pushing
243 arguments on the stack, but that is too difficult to compute, so we just
244 assume any function call might require the stack. */
246 static tree calls_function_save_exprs;
249 calls_function (exp, which)
255 calls_function_save_exprs = 0;
256 val = calls_function_1 (exp, which);
257 calls_function_save_exprs = 0;
261 /* Recursive function to do the work of above function. */
264 calls_function_1 (exp, which)
269 enum tree_code code = TREE_CODE (exp);
270 int class = TREE_CODE_CLASS (code);
271 int length = first_rtl_op (code);
273 /* If this code is language-specific, we don't know what it will do. */
274 if ((int) code >= NUM_TREE_CODES)
282 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
284 && (TYPE_RETURNS_STACK_DEPRESSED
285 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))))
287 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
288 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
290 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
292 & ECF_MAY_BE_ALLOCA))
301 for (tem = CONSTRUCTOR_ELTS (exp); tem != 0; tem = TREE_CHAIN (tem))
302 if (calls_function_1 (TREE_VALUE (tem), which))
309 if (SAVE_EXPR_RTL (exp) != 0)
311 if (value_member (exp, calls_function_save_exprs))
313 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
314 calls_function_save_exprs);
315 return (TREE_OPERAND (exp, 0) != 0
316 && calls_function_1 (TREE_OPERAND (exp, 0), which));
323 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
324 if (DECL_INITIAL (local) != 0
325 && calls_function_1 (DECL_INITIAL (local), which))
328 for (subblock = BLOCK_SUBBLOCKS (exp);
330 subblock = TREE_CHAIN (subblock))
331 if (calls_function_1 (subblock, which))
337 for (; exp != 0; exp = TREE_CHAIN (exp))
338 if (calls_function_1 (TREE_VALUE (exp), which))
346 /* Only expressions, references, and blocks can contain calls. */
347 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
350 for (i = 0; i < length; i++)
351 if (TREE_OPERAND (exp, i) != 0
352 && calls_function_1 (TREE_OPERAND (exp, i), which))
358 /* Force FUNEXP into a form suitable for the address of a CALL,
359 and return that as an rtx. Also load the static chain register
360 if FNDECL is a nested function.
362 CALL_FUSAGE points to a variable holding the prospective
363 CALL_INSN_FUNCTION_USAGE information. */
366 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen, sibcallp)
373 rtx static_chain_value = 0;
375 funexp = protect_from_queue (funexp, 0);
378 /* Get possible static chain value for nested function in C. */
379 static_chain_value = lookup_static_chain (fndecl);
381 /* Make a valid memory address and copy constants thru pseudo-regs,
382 but not for a constant address if -fno-function-cse. */
383 if (GET_CODE (funexp) != SYMBOL_REF)
384 /* If we are using registers for parameters, force the
385 function address into a register now. */
386 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
387 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
388 : memory_address (FUNCTION_MODE, funexp));
391 #ifndef NO_FUNCTION_CSE
392 if (optimize && ! flag_no_function_cse)
393 #ifdef NO_RECURSIVE_FUNCTION_CSE
394 if (fndecl != current_function_decl)
396 funexp = force_reg (Pmode, funexp);
400 if (static_chain_value != 0)
402 emit_move_insn (static_chain_rtx, static_chain_value);
404 if (GET_CODE (static_chain_rtx) == REG)
405 use_reg (call_fusage, static_chain_rtx);
411 /* Generate instructions to call function FUNEXP,
412 and optionally pop the results.
413 The CALL_INSN is the first insn generated.
415 FNDECL is the declaration node of the function. This is given to the
416 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
418 FUNTYPE is the data type of the function. This is given to the macro
419 RETURN_POPS_ARGS to determine whether this function pops its own args.
420 We used to allow an identifier for library functions, but that doesn't
421 work when the return type is an aggregate type and the calling convention
422 says that the pointer to this aggregate is to be popped by the callee.
424 STACK_SIZE is the number of bytes of arguments on the stack,
425 ROUNDED_STACK_SIZE is that number rounded up to
426 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
427 both to put into the call insn and to generate explicit popping
430 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
431 It is zero if this call doesn't want a structure value.
433 NEXT_ARG_REG is the rtx that results from executing
434 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
435 just after all the args have had their registers assigned.
436 This could be whatever you like, but normally it is the first
437 arg-register beyond those used for args in this call,
438 or 0 if all the arg-registers are used in this call.
439 It is passed on to `gen_call' so you can put this info in the call insn.
441 VALREG is a hard register in which a value is returned,
442 or 0 if the call does not return a value.
444 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
445 the args to this call were processed.
446 We restore `inhibit_defer_pop' to that value.
448 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
449 denote registers used by the called function. */
452 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
453 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
454 call_fusage, ecf_flags, args_so_far)
456 tree fndecl ATTRIBUTE_UNUSED;
457 tree funtype ATTRIBUTE_UNUSED;
458 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
459 HOST_WIDE_INT rounded_stack_size;
460 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
461 rtx next_arg_reg ATTRIBUTE_UNUSED;
463 int old_inhibit_defer_pop;
466 CUMULATIVE_ARGS *args_so_far ATTRIBUTE_UNUSED;
468 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
470 int already_popped = 0;
471 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
472 #if defined (HAVE_call) && defined (HAVE_call_value)
473 rtx struct_value_size_rtx;
474 struct_value_size_rtx = GEN_INT (struct_value_size);
477 #ifdef CALL_POPS_ARGS
478 n_popped += CALL_POPS_ARGS (* args_so_far);
481 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
482 and we don't want to load it into a register as an optimization,
483 because prepare_call_address already did it if it should be done. */
484 if (GET_CODE (funexp) != SYMBOL_REF)
485 funexp = memory_address (FUNCTION_MODE, funexp);
487 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
488 if ((ecf_flags & ECF_SIBCALL)
489 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
490 && (n_popped > 0 || stack_size == 0))
492 rtx n_pop = GEN_INT (n_popped);
495 /* If this subroutine pops its own args, record that in the call insn
496 if possible, for the sake of frame pointer elimination. */
499 pat = GEN_SIBCALL_VALUE_POP (valreg,
500 gen_rtx_MEM (FUNCTION_MODE, funexp),
501 rounded_stack_size_rtx, next_arg_reg,
504 pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
505 rounded_stack_size_rtx, next_arg_reg, n_pop);
507 emit_call_insn (pat);
513 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
514 /* If the target has "call" or "call_value" insns, then prefer them
515 if no arguments are actually popped. If the target does not have
516 "call" or "call_value" insns, then we must use the popping versions
517 even if the call has no arguments to pop. */
518 #if defined (HAVE_call) && defined (HAVE_call_value)
519 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
520 && n_popped > 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
522 if (HAVE_call_pop && HAVE_call_value_pop)
525 rtx n_pop = GEN_INT (n_popped);
528 /* If this subroutine pops its own args, record that in the call insn
529 if possible, for the sake of frame pointer elimination. */
532 pat = GEN_CALL_VALUE_POP (valreg,
533 gen_rtx_MEM (FUNCTION_MODE, funexp),
534 rounded_stack_size_rtx, next_arg_reg, n_pop);
536 pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
537 rounded_stack_size_rtx, next_arg_reg, n_pop);
539 emit_call_insn (pat);
545 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
546 if ((ecf_flags & ECF_SIBCALL)
547 && HAVE_sibcall && HAVE_sibcall_value)
550 emit_call_insn (GEN_SIBCALL_VALUE (valreg,
551 gen_rtx_MEM (FUNCTION_MODE, funexp),
552 rounded_stack_size_rtx,
553 next_arg_reg, NULL_RTX));
555 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
556 rounded_stack_size_rtx, next_arg_reg,
557 struct_value_size_rtx));
562 #if defined (HAVE_call) && defined (HAVE_call_value)
563 if (HAVE_call && HAVE_call_value)
566 emit_call_insn (GEN_CALL_VALUE (valreg,
567 gen_rtx_MEM (FUNCTION_MODE, funexp),
568 rounded_stack_size_rtx, next_arg_reg,
571 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
572 rounded_stack_size_rtx, next_arg_reg,
573 struct_value_size_rtx));
579 /* Find the CALL insn we just emitted. */
580 for (call_insn = get_last_insn ();
581 call_insn && GET_CODE (call_insn) != CALL_INSN;
582 call_insn = PREV_INSN (call_insn))
588 /* Mark memory as used for "pure" function call. */
589 if (ecf_flags & ECF_PURE)
593 gen_rtx_USE (VOIDmode,
594 gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode))),
597 /* Put the register usage information on the CALL. If there is already
598 some usage information, put ours at the end. */
599 if (CALL_INSN_FUNCTION_USAGE (call_insn))
603 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
604 link = XEXP (link, 1))
607 XEXP (link, 1) = call_fusage;
610 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
612 /* If this is a const call, then set the insn's unchanging bit. */
613 if (ecf_flags & (ECF_CONST | ECF_PURE))
614 CONST_OR_PURE_CALL_P (call_insn) = 1;
616 /* If this call can't throw, attach a REG_EH_REGION reg note to that
618 if (ecf_flags & ECF_NOTHROW)
619 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
620 REG_NOTES (call_insn));
622 note_eh_region_may_contain_throw ();
624 if (ecf_flags & ECF_NORETURN)
625 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_NORETURN, const0_rtx,
626 REG_NOTES (call_insn));
627 if (ecf_flags & ECF_ALWAYS_RETURN)
628 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN, const0_rtx,
629 REG_NOTES (call_insn));
631 if (ecf_flags & ECF_RETURNS_TWICE)
633 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_SETJMP, const0_rtx,
634 REG_NOTES (call_insn));
635 current_function_calls_setjmp = 1;
638 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
640 /* Restore this now, so that we do defer pops for this call's args
641 if the context of the call as a whole permits. */
642 inhibit_defer_pop = old_inhibit_defer_pop;
644 /* Don't bother cleaning up after a noreturn function. */
645 if (ecf_flags & (ECF_NORETURN | ECF_LONGJMP))
651 CALL_INSN_FUNCTION_USAGE (call_insn)
652 = gen_rtx_EXPR_LIST (VOIDmode,
653 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
654 CALL_INSN_FUNCTION_USAGE (call_insn));
655 rounded_stack_size -= n_popped;
656 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
657 stack_pointer_delta -= n_popped;
660 if (!ACCUMULATE_OUTGOING_ARGS)
662 /* If returning from the subroutine does not automatically pop the args,
663 we need an instruction to pop them sooner or later.
664 Perhaps do it now; perhaps just record how much space to pop later.
666 If returning from the subroutine does pop the args, indicate that the
667 stack pointer will be changed. */
669 if (rounded_stack_size != 0)
671 if (ecf_flags & ECF_SP_DEPRESSED)
672 /* Just pretend we did the pop. */
673 stack_pointer_delta -= rounded_stack_size;
674 else if (flag_defer_pop && inhibit_defer_pop == 0
675 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
676 pending_stack_adjust += rounded_stack_size;
678 adjust_stack (rounded_stack_size_rtx);
681 /* When we accumulate outgoing args, we must avoid any stack manipulations.
682 Restore the stack pointer to its original value now. Usually
683 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
684 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
685 popping variants of functions exist as well.
687 ??? We may optimize similar to defer_pop above, but it is
688 probably not worthwhile.
690 ??? It will be worthwhile to enable combine_stack_adjustments even for
693 anti_adjust_stack (GEN_INT (n_popped));
696 /* Determine if the function identified by NAME and FNDECL is one with
697 special properties we wish to know about.
699 For example, if the function might return more than one time (setjmp), then
700 set RETURNS_TWICE to a nonzero value.
702 Similarly set LONGJMP for if the function is in the longjmp family.
704 Set MALLOC for any of the standard memory allocation functions which
705 allocate from the heap.
707 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
708 space from the stack such as alloca. */
711 special_function_p (fndecl, flags)
715 if (! (flags & ECF_MALLOC)
716 && fndecl && DECL_NAME (fndecl)
717 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
718 /* Exclude functions not at the file scope, or not `extern',
719 since they are not the magic functions we would otherwise
721 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
723 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
724 const char *tname = name;
726 /* We assume that alloca will always be called by name. It
727 makes no sense to pass it as a pointer-to-function to
728 anything that does not understand its behavior. */
729 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
731 && ! strcmp (name, "alloca"))
732 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
734 && ! strcmp (name, "__builtin_alloca"))))
735 flags |= ECF_MAY_BE_ALLOCA;
737 /* Disregard prefix _, __ or __x. */
740 if (name[1] == '_' && name[2] == 'x')
742 else if (name[1] == '_')
751 && (! strcmp (tname, "setjmp")
752 || ! strcmp (tname, "setjmp_syscall")))
754 && ! strcmp (tname, "sigsetjmp"))
756 && ! strcmp (tname, "savectx")))
757 flags |= ECF_RETURNS_TWICE;
760 && ! strcmp (tname, "siglongjmp"))
761 flags |= ECF_LONGJMP;
763 else if ((tname[0] == 'q' && tname[1] == 's'
764 && ! strcmp (tname, "qsetjmp"))
765 || (tname[0] == 'v' && tname[1] == 'f'
766 && ! strcmp (tname, "vfork")))
767 flags |= ECF_RETURNS_TWICE;
769 else if (tname[0] == 'l' && tname[1] == 'o'
770 && ! strcmp (tname, "longjmp"))
771 flags |= ECF_LONGJMP;
773 else if ((tname[0] == 'f' && tname[1] == 'o'
774 && ! strcmp (tname, "fork"))
775 /* Linux specific: __clone. check NAME to insist on the
776 leading underscores, to avoid polluting the ISO / POSIX
778 || (name[0] == '_' && name[1] == '_'
779 && ! strcmp (tname, "clone"))
780 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
781 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
783 || ((tname[5] == 'p' || tname[5] == 'e')
784 && tname[6] == '\0'))))
785 flags |= ECF_FORK_OR_EXEC;
787 /* Do not add any more malloc-like functions to this list,
788 instead mark them as malloc functions using the malloc attribute.
789 Note, realloc is not suitable for attribute malloc since
790 it may return the same address across multiple calls.
791 C++ operator new is not suitable because it is not required
792 to return a unique pointer; indeed, the standard placement new
793 just returns its argument. */
794 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl))) == Pmode
795 && (! strcmp (tname, "malloc")
796 || ! strcmp (tname, "calloc")
797 || ! strcmp (tname, "strdup")))
803 /* Return nonzero when tree represent call to longjmp. */
806 setjmp_call_p (fndecl)
809 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
812 /* Return true when exp contains alloca call. */
817 if (TREE_CODE (exp) == CALL_EXPR
818 && TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
819 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
821 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
822 0) & ECF_MAY_BE_ALLOCA))
827 /* Detect flags (function attributes) from the function decl or type node. */
830 flags_from_decl_or_type (exp)
835 /* ??? We can't set IS_MALLOC for function types? */
838 type = TREE_TYPE (exp);
840 /* The function exp may have the `malloc' attribute. */
841 if (DECL_P (exp) && DECL_IS_MALLOC (exp))
844 /* The function exp may have the `pure' attribute. */
845 if (DECL_P (exp) && DECL_IS_PURE (exp))
846 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
848 if (TREE_NOTHROW (exp))
849 flags |= ECF_NOTHROW;
851 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
852 flags |= ECF_LIBCALL_BLOCK;
855 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
858 if (TREE_THIS_VOLATILE (exp))
859 flags |= ECF_NORETURN;
861 /* Mark if the function returns with the stack pointer depressed. We
862 cannot consider it pure or constant in that case. */
863 if (TREE_CODE (type) == FUNCTION_TYPE && TYPE_RETURNS_STACK_DEPRESSED (type))
865 flags |= ECF_SP_DEPRESSED;
866 flags &= ~(ECF_PURE | ECF_CONST | ECF_LIBCALL_BLOCK);
872 /* Precompute all register parameters as described by ARGS, storing values
873 into fields within the ARGS array.
875 NUM_ACTUALS indicates the total number elements in the ARGS array.
877 Set REG_PARM_SEEN if we encounter a register parameter. */
880 precompute_register_parameters (num_actuals, args, reg_parm_seen)
882 struct arg_data *args;
889 for (i = 0; i < num_actuals; i++)
890 if (args[i].reg != 0 && ! args[i].pass_on_stack)
894 if (args[i].value == 0)
897 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
899 preserve_temp_slots (args[i].value);
902 /* ANSI doesn't require a sequence point here,
903 but PCC has one, so this will avoid some problems. */
907 /* If the value is a non-legitimate constant, force it into a
908 pseudo now. TLS symbols sometimes need a call to resolve. */
909 if (CONSTANT_P (args[i].value)
910 && !LEGITIMATE_CONSTANT_P (args[i].value))
911 args[i].value = force_reg (args[i].mode, args[i].value);
913 /* If we are to promote the function arg to a wider mode,
916 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
918 = convert_modes (args[i].mode,
919 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
920 args[i].value, args[i].unsignedp);
922 /* If the value is expensive, and we are inside an appropriately
923 short loop, put the value into a pseudo and then put the pseudo
926 For small register classes, also do this if this call uses
927 register parameters. This is to avoid reload conflicts while
928 loading the parameters registers. */
930 if ((! (GET_CODE (args[i].value) == REG
931 || (GET_CODE (args[i].value) == SUBREG
932 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
933 && args[i].mode != BLKmode
934 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
935 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
936 || preserve_subexpressions_p ()))
937 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
941 #ifdef REG_PARM_STACK_SPACE
943 /* The argument list is the property of the called routine and it
944 may clobber it. If the fixed area has been used for previous
945 parameters, we must save and restore it. */
948 save_fixed_argument_area (reg_parm_stack_space, argblock,
949 low_to_save, high_to_save)
950 int reg_parm_stack_space;
956 rtx save_area = NULL_RTX;
958 /* Compute the boundary of the that needs to be saved, if any. */
959 #ifdef ARGS_GROW_DOWNWARD
960 for (i = 0; i < reg_parm_stack_space + 1; i++)
962 for (i = 0; i < reg_parm_stack_space; i++)
965 if (i >= highest_outgoing_arg_in_use
966 || stack_usage_map[i] == 0)
969 if (*low_to_save == -1)
975 if (*low_to_save >= 0)
977 int num_to_save = *high_to_save - *low_to_save + 1;
978 enum machine_mode save_mode
979 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
982 /* If we don't have the required alignment, must do this in BLKmode. */
983 if ((*low_to_save & (MIN (GET_MODE_SIZE (save_mode),
984 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
987 #ifdef ARGS_GROW_DOWNWARD
989 = gen_rtx_MEM (save_mode,
990 memory_address (save_mode,
991 plus_constant (argblock,
994 stack_area = gen_rtx_MEM (save_mode,
995 memory_address (save_mode,
996 plus_constant (argblock,
1000 set_mem_align (stack_area, PARM_BOUNDARY);
1001 if (save_mode == BLKmode)
1003 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
1004 emit_block_move (validize_mem (save_area), stack_area,
1005 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
1009 save_area = gen_reg_rtx (save_mode);
1010 emit_move_insn (save_area, stack_area);
1018 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
1024 enum machine_mode save_mode = GET_MODE (save_area);
1025 #ifdef ARGS_GROW_DOWNWARD
1027 = gen_rtx_MEM (save_mode,
1028 memory_address (save_mode,
1029 plus_constant (argblock,
1033 = gen_rtx_MEM (save_mode,
1034 memory_address (save_mode,
1035 plus_constant (argblock,
1039 if (save_mode != BLKmode)
1040 emit_move_insn (stack_area, save_area);
1042 emit_block_move (stack_area, validize_mem (save_area),
1043 GEN_INT (high_to_save - low_to_save + 1),
1044 BLOCK_OP_CALL_PARM);
1046 #endif /* REG_PARM_STACK_SPACE */
1048 /* If any elements in ARGS refer to parameters that are to be passed in
1049 registers, but not in memory, and whose alignment does not permit a
1050 direct copy into registers. Copy the values into a group of pseudos
1051 which we will later copy into the appropriate hard registers.
1053 Pseudos for each unaligned argument will be stored into the array
1054 args[argnum].aligned_regs. The caller is responsible for deallocating
1055 the aligned_regs array if it is nonzero. */
1058 store_unaligned_arguments_into_pseudos (args, num_actuals)
1059 struct arg_data *args;
1064 for (i = 0; i < num_actuals; i++)
1065 if (args[i].reg != 0 && ! args[i].pass_on_stack
1066 && args[i].mode == BLKmode
1067 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1068 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1070 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1071 int big_endian_correction = 0;
1073 args[i].n_aligned_regs
1074 = args[i].partial ? args[i].partial
1075 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1077 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
1078 * args[i].n_aligned_regs);
1080 /* Structures smaller than a word are aligned to the least
1081 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1082 this means we must skip the empty high order bytes when
1083 calculating the bit offset. */
1084 if (BYTES_BIG_ENDIAN
1085 && bytes < UNITS_PER_WORD)
1086 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1088 for (j = 0; j < args[i].n_aligned_regs; j++)
1090 rtx reg = gen_reg_rtx (word_mode);
1091 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1092 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1094 args[i].aligned_regs[j] = reg;
1096 /* There is no need to restrict this code to loading items
1097 in TYPE_ALIGN sized hunks. The bitfield instructions can
1098 load up entire word sized registers efficiently.
1100 ??? This may not be needed anymore.
1101 We use to emit a clobber here but that doesn't let later
1102 passes optimize the instructions we emit. By storing 0 into
1103 the register later passes know the first AND to zero out the
1104 bitfield being set in the register is unnecessary. The store
1105 of 0 will be deleted as will at least the first AND. */
1107 emit_move_insn (reg, const0_rtx);
1109 bytes -= bitsize / BITS_PER_UNIT;
1110 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
1111 extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1112 word_mode, word_mode,
1119 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1122 NUM_ACTUALS is the total number of parameters.
1124 N_NAMED_ARGS is the total number of named arguments.
1126 FNDECL is the tree code for the target of this call (if known)
1128 ARGS_SO_FAR holds state needed by the target to know where to place
1131 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1132 for arguments which are passed in registers.
1134 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1135 and may be modified by this routine.
1137 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1138 flags which may may be modified by this routine. */
1141 initialize_argument_information (num_actuals, args, args_size, n_named_args,
1142 actparms, fndecl, args_so_far,
1143 reg_parm_stack_space, old_stack_level,
1144 old_pending_adj, must_preallocate,
1146 int num_actuals ATTRIBUTE_UNUSED;
1147 struct arg_data *args;
1148 struct args_size *args_size;
1149 int n_named_args ATTRIBUTE_UNUSED;
1152 CUMULATIVE_ARGS *args_so_far;
1153 int reg_parm_stack_space;
1154 rtx *old_stack_level;
1155 int *old_pending_adj;
1156 int *must_preallocate;
1159 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1162 /* Count arg position in order args appear. */
1165 struct args_size alignment_pad;
1169 args_size->constant = 0;
1172 /* In this loop, we consider args in the order they are written.
1173 We fill up ARGS from the front or from the back if necessary
1174 so that in any case the first arg to be pushed ends up at the front. */
1176 if (PUSH_ARGS_REVERSED)
1178 i = num_actuals - 1, inc = -1;
1179 /* In this case, must reverse order of args
1180 so that we compute and push the last arg first. */
1187 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1188 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1190 tree type = TREE_TYPE (TREE_VALUE (p));
1192 enum machine_mode mode;
1194 args[i].tree_value = TREE_VALUE (p);
1196 /* Replace erroneous argument with constant zero. */
1197 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1198 args[i].tree_value = integer_zero_node, type = integer_type_node;
1200 /* If TYPE is a transparent union, pass things the way we would
1201 pass the first field of the union. We have already verified that
1202 the modes are the same. */
1203 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1204 type = TREE_TYPE (TYPE_FIELDS (type));
1206 /* Decide where to pass this arg.
1208 args[i].reg is nonzero if all or part is passed in registers.
1210 args[i].partial is nonzero if part but not all is passed in registers,
1211 and the exact value says how many words are passed in registers.
1213 args[i].pass_on_stack is nonzero if the argument must at least be
1214 computed on the stack. It may then be loaded back into registers
1215 if args[i].reg is nonzero.
1217 These decisions are driven by the FUNCTION_... macros and must agree
1218 with those made by function.c. */
1220 /* See if this argument should be passed by invisible reference. */
1221 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1222 && contains_placeholder_p (TYPE_SIZE (type)))
1223 || TREE_ADDRESSABLE (type)
1224 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1225 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1226 type, argpos < n_named_args)
1230 /* If we're compiling a thunk, pass through invisible
1231 references instead of making a copy. */
1232 if (current_function_is_thunk
1233 #ifdef FUNCTION_ARG_CALLEE_COPIES
1234 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1235 type, argpos < n_named_args)
1236 /* If it's in a register, we must make a copy of it too. */
1237 /* ??? Is this a sufficient test? Is there a better one? */
1238 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1239 && REG_P (DECL_RTL (args[i].tree_value)))
1240 && ! TREE_ADDRESSABLE (type))
1244 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1245 new object from the argument. If we are passing by
1246 invisible reference, the callee will do that for us, so we
1247 can strip off the TARGET_EXPR. This is not always safe,
1248 but it is safe in the only case where this is a useful
1249 optimization; namely, when the argument is a plain object.
1250 In that case, the frontend is just asking the backend to
1251 make a bitwise copy of the argument. */
1253 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1254 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1255 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1256 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1258 args[i].tree_value = build1 (ADDR_EXPR,
1259 build_pointer_type (type),
1260 args[i].tree_value);
1261 type = build_pointer_type (type);
1263 else if (TREE_CODE (args[i].tree_value) == TARGET_EXPR)
1265 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1266 We implement this by passing the address of the temporary
1267 rather than expanding it into another allocated slot. */
1268 args[i].tree_value = build1 (ADDR_EXPR,
1269 build_pointer_type (type),
1270 args[i].tree_value);
1271 type = build_pointer_type (type);
1275 /* We make a copy of the object and pass the address to the
1276 function being called. */
1279 if (!COMPLETE_TYPE_P (type)
1280 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1281 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1282 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1283 STACK_CHECK_MAX_VAR_SIZE))))
1285 /* This is a variable-sized object. Make space on the stack
1287 rtx size_rtx = expr_size (TREE_VALUE (p));
1289 if (*old_stack_level == 0)
1291 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1292 *old_pending_adj = pending_stack_adjust;
1293 pending_stack_adjust = 0;
1296 copy = gen_rtx_MEM (BLKmode,
1297 allocate_dynamic_stack_space
1298 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1299 set_mem_attributes (copy, type, 1);
1302 copy = assign_temp (type, 0, 1, 0);
1304 store_expr (args[i].tree_value, copy, 0);
1305 *ecf_flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
1307 args[i].tree_value = build1 (ADDR_EXPR,
1308 build_pointer_type (type),
1309 make_tree (type, copy));
1310 type = build_pointer_type (type);
1314 mode = TYPE_MODE (type);
1315 unsignedp = TREE_UNSIGNED (type);
1317 #ifdef PROMOTE_FUNCTION_ARGS
1318 mode = promote_mode (type, mode, &unsignedp, 1);
1321 args[i].unsignedp = unsignedp;
1322 args[i].mode = mode;
1324 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1325 argpos < n_named_args);
1326 #ifdef FUNCTION_INCOMING_ARG
1327 /* If this is a sibling call and the machine has register windows, the
1328 register window has to be unwinded before calling the routine, so
1329 arguments have to go into the incoming registers. */
1330 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1331 argpos < n_named_args);
1333 args[i].tail_call_reg = args[i].reg;
1336 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1339 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1340 argpos < n_named_args);
1343 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1345 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1346 it means that we are to pass this arg in the register(s) designated
1347 by the PARALLEL, but also to pass it in the stack. */
1348 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1349 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1350 args[i].pass_on_stack = 1;
1352 /* If this is an addressable type, we must preallocate the stack
1353 since we must evaluate the object into its final location.
1355 If this is to be passed in both registers and the stack, it is simpler
1357 if (TREE_ADDRESSABLE (type)
1358 || (args[i].pass_on_stack && args[i].reg != 0))
1359 *must_preallocate = 1;
1361 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1362 we cannot consider this function call constant. */
1363 if (TREE_ADDRESSABLE (type))
1364 *ecf_flags &= ~ECF_LIBCALL_BLOCK;
1366 /* Compute the stack-size of this argument. */
1367 if (args[i].reg == 0 || args[i].partial != 0
1368 || reg_parm_stack_space > 0
1369 || args[i].pass_on_stack)
1370 locate_and_pad_parm (mode, type,
1371 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1376 fndecl, args_size, &args[i].offset,
1377 &args[i].size, &alignment_pad);
1379 #ifndef ARGS_GROW_DOWNWARD
1380 args[i].slot_offset = *args_size;
1383 args[i].alignment_pad = alignment_pad;
1385 /* If a part of the arg was put into registers,
1386 don't include that part in the amount pushed. */
1387 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1388 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1389 / (PARM_BOUNDARY / BITS_PER_UNIT)
1390 * (PARM_BOUNDARY / BITS_PER_UNIT));
1392 /* Update ARGS_SIZE, the total stack space for args so far. */
1394 args_size->constant += args[i].size.constant;
1395 if (args[i].size.var)
1397 ADD_PARM_SIZE (*args_size, args[i].size.var);
1400 /* Since the slot offset points to the bottom of the slot,
1401 we must record it after incrementing if the args grow down. */
1402 #ifdef ARGS_GROW_DOWNWARD
1403 args[i].slot_offset = *args_size;
1405 args[i].slot_offset.constant = -args_size->constant;
1407 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1410 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1411 have been used, etc. */
1413 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1414 argpos < n_named_args);
1418 /* Update ARGS_SIZE to contain the total size for the argument block.
1419 Return the original constant component of the argument block's size.
1421 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1422 for arguments passed in registers. */
1425 compute_argument_block_size (reg_parm_stack_space, args_size,
1426 preferred_stack_boundary)
1427 int reg_parm_stack_space;
1428 struct args_size *args_size;
1429 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1431 int unadjusted_args_size = args_size->constant;
1433 /* For accumulate outgoing args mode we don't need to align, since the frame
1434 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1435 backends from generating misaligned frame sizes. */
1436 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1437 preferred_stack_boundary = STACK_BOUNDARY;
1439 /* Compute the actual size of the argument block required. The variable
1440 and constant sizes must be combined, the size may have to be rounded,
1441 and there may be a minimum required size. */
1445 args_size->var = ARGS_SIZE_TREE (*args_size);
1446 args_size->constant = 0;
1448 preferred_stack_boundary /= BITS_PER_UNIT;
1449 if (preferred_stack_boundary > 1)
1451 /* We don't handle this case yet. To handle it correctly we have
1452 to add the delta, round and subtract the delta.
1453 Currently no machine description requires this support. */
1454 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1456 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1459 if (reg_parm_stack_space > 0)
1462 = size_binop (MAX_EXPR, args_size->var,
1463 ssize_int (reg_parm_stack_space));
1465 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1466 /* The area corresponding to register parameters is not to count in
1467 the size of the block we need. So make the adjustment. */
1469 = size_binop (MINUS_EXPR, args_size->var,
1470 ssize_int (reg_parm_stack_space));
1476 preferred_stack_boundary /= BITS_PER_UNIT;
1477 if (preferred_stack_boundary < 1)
1478 preferred_stack_boundary = 1;
1479 args_size->constant = (((args_size->constant
1480 + stack_pointer_delta
1481 + preferred_stack_boundary - 1)
1482 / preferred_stack_boundary
1483 * preferred_stack_boundary)
1484 - stack_pointer_delta);
1486 args_size->constant = MAX (args_size->constant,
1487 reg_parm_stack_space);
1489 #ifdef MAYBE_REG_PARM_STACK_SPACE
1490 if (reg_parm_stack_space == 0)
1491 args_size->constant = 0;
1494 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1495 args_size->constant -= reg_parm_stack_space;
1498 return unadjusted_args_size;
1501 /* Precompute parameters as needed for a function call.
1503 FLAGS is mask of ECF_* constants.
1505 NUM_ACTUALS is the number of arguments.
1507 ARGS is an array containing information for each argument; this
1508 routine fills in the INITIAL_VALUE and VALUE fields for each
1509 precomputed argument. */
1512 precompute_arguments (flags, num_actuals, args)
1515 struct arg_data *args;
1519 /* If this function call is cse'able, precompute all the parameters.
1520 Note that if the parameter is constructed into a temporary, this will
1521 cause an additional copy because the parameter will be constructed
1522 into a temporary location and then copied into the outgoing arguments.
1523 If a parameter contains a call to alloca and this function uses the
1524 stack, precompute the parameter. */
1526 /* If we preallocated the stack space, and some arguments must be passed
1527 on the stack, then we must precompute any parameter which contains a
1528 function call which will store arguments on the stack.
1529 Otherwise, evaluating the parameter may clobber previous parameters
1530 which have already been stored into the stack. (we have code to avoid
1531 such case by saving the outgoing stack arguments, but it results in
1534 for (i = 0; i < num_actuals; i++)
1535 if ((flags & ECF_LIBCALL_BLOCK)
1536 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1538 enum machine_mode mode;
1540 /* If this is an addressable type, we cannot pre-evaluate it. */
1541 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1545 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1547 /* ANSI doesn't require a sequence point here,
1548 but PCC has one, so this will avoid some problems. */
1551 args[i].initial_value = args[i].value
1552 = protect_from_queue (args[i].value, 0);
1554 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1555 if (mode != args[i].mode)
1558 = convert_modes (args[i].mode, mode,
1559 args[i].value, args[i].unsignedp);
1560 #ifdef PROMOTE_FOR_CALL_ONLY
1561 /* CSE will replace this only if it contains args[i].value
1562 pseudo, so convert it down to the declared mode using
1564 if (GET_CODE (args[i].value) == REG
1565 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1567 args[i].initial_value
1568 = gen_lowpart_SUBREG (mode, args[i].value);
1569 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1570 SUBREG_PROMOTED_UNSIGNED_SET (args[i].initial_value,
1578 /* Given the current state of MUST_PREALLOCATE and information about
1579 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1580 compute and return the final value for MUST_PREALLOCATE. */
1583 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1584 int must_preallocate;
1586 struct arg_data *args;
1587 struct args_size *args_size;
1589 /* See if we have or want to preallocate stack space.
1591 If we would have to push a partially-in-regs parm
1592 before other stack parms, preallocate stack space instead.
1594 If the size of some parm is not a multiple of the required stack
1595 alignment, we must preallocate.
1597 If the total size of arguments that would otherwise create a copy in
1598 a temporary (such as a CALL) is more than half the total argument list
1599 size, preallocation is faster.
1601 Another reason to preallocate is if we have a machine (like the m88k)
1602 where stack alignment is required to be maintained between every
1603 pair of insns, not just when the call is made. However, we assume here
1604 that such machines either do not have push insns (and hence preallocation
1605 would occur anyway) or the problem is taken care of with
1608 if (! must_preallocate)
1610 int partial_seen = 0;
1611 int copy_to_evaluate_size = 0;
1614 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1616 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1618 else if (partial_seen && args[i].reg == 0)
1619 must_preallocate = 1;
1621 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1622 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1623 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1624 || TREE_CODE (args[i].tree_value) == COND_EXPR
1625 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1626 copy_to_evaluate_size
1627 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1630 if (copy_to_evaluate_size * 2 >= args_size->constant
1631 && args_size->constant > 0)
1632 must_preallocate = 1;
1634 return must_preallocate;
1637 /* If we preallocated stack space, compute the address of each argument
1638 and store it into the ARGS array.
1640 We need not ensure it is a valid memory address here; it will be
1641 validized when it is used.
1643 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1646 compute_argument_addresses (args, argblock, num_actuals)
1647 struct arg_data *args;
1653 rtx arg_reg = argblock;
1654 int i, arg_offset = 0;
1656 if (GET_CODE (argblock) == PLUS)
1657 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1659 for (i = 0; i < num_actuals; i++)
1661 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1662 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1665 /* Skip this parm if it will not be passed on the stack. */
1666 if (! args[i].pass_on_stack && args[i].reg != 0)
1669 if (GET_CODE (offset) == CONST_INT)
1670 addr = plus_constant (arg_reg, INTVAL (offset));
1672 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1674 addr = plus_constant (addr, arg_offset);
1675 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1676 set_mem_align (args[i].stack, PARM_BOUNDARY);
1677 set_mem_attributes (args[i].stack,
1678 TREE_TYPE (args[i].tree_value), 1);
1680 if (GET_CODE (slot_offset) == CONST_INT)
1681 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1683 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1685 addr = plus_constant (addr, arg_offset);
1686 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1687 set_mem_align (args[i].stack_slot, PARM_BOUNDARY);
1688 set_mem_attributes (args[i].stack_slot,
1689 TREE_TYPE (args[i].tree_value), 1);
1691 /* Function incoming arguments may overlap with sibling call
1692 outgoing arguments and we cannot allow reordering of reads
1693 from function arguments with stores to outgoing arguments
1694 of sibling calls. */
1695 set_mem_alias_set (args[i].stack, 0);
1696 set_mem_alias_set (args[i].stack_slot, 0);
1701 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1702 in a call instruction.
1704 FNDECL is the tree node for the target function. For an indirect call
1705 FNDECL will be NULL_TREE.
1707 ADDR is the operand 0 of CALL_EXPR for this call. */
1710 rtx_for_function_call (fndecl, addr)
1716 /* Get the function to call, in the form of RTL. */
1719 /* If this is the first use of the function, see if we need to
1720 make an external definition for it. */
1721 if (! TREE_USED (fndecl))
1723 assemble_external (fndecl);
1724 TREE_USED (fndecl) = 1;
1727 /* Get a SYMBOL_REF rtx for the function address. */
1728 funexp = XEXP (DECL_RTL (fndecl), 0);
1731 /* Generate an rtx (probably a pseudo-register) for the address. */
1736 = expand_expr (addr, NULL_RTX, VOIDmode, 0);
1737 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1743 /* Do the register loads required for any wholly-register parms or any
1744 parms which are passed both on the stack and in a register. Their
1745 expressions were already evaluated.
1747 Mark all register-parms as living through the call, putting these USE
1748 insns in the CALL_INSN_FUNCTION_USAGE field. */
1751 load_register_parameters (args, num_actuals, call_fusage, flags)
1752 struct arg_data *args;
1759 #ifdef LOAD_ARGS_REVERSED
1760 for (i = num_actuals - 1; i >= 0; i--)
1762 for (i = 0; i < num_actuals; i++)
1765 rtx reg = ((flags & ECF_SIBCALL)
1766 ? args[i].tail_call_reg : args[i].reg);
1767 int partial = args[i].partial;
1772 /* Set to non-negative if must move a word at a time, even if just
1773 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1774 we just use a normal move insn. This value can be zero if the
1775 argument is a zero size structure with no fields. */
1776 nregs = (partial ? partial
1777 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1778 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1779 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1782 /* Handle calls that pass values in multiple non-contiguous
1783 locations. The Irix 6 ABI has examples of this. */
1785 if (GET_CODE (reg) == PARALLEL)
1786 emit_group_load (reg, args[i].value,
1787 int_size_in_bytes (TREE_TYPE (args[i].tree_value)));
1789 /* If simple case, just do move. If normal partial, store_one_arg
1790 has already loaded the register for us. In all other cases,
1791 load the register(s) from memory. */
1793 else if (nregs == -1)
1794 emit_move_insn (reg, args[i].value);
1796 /* If we have pre-computed the values to put in the registers in
1797 the case of non-aligned structures, copy them in now. */
1799 else if (args[i].n_aligned_regs != 0)
1800 for (j = 0; j < args[i].n_aligned_regs; j++)
1801 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1802 args[i].aligned_regs[j]);
1804 else if (partial == 0 || args[i].pass_on_stack)
1805 move_block_to_reg (REGNO (reg),
1806 validize_mem (args[i].value), nregs,
1809 /* Handle calls that pass values in multiple non-contiguous
1810 locations. The Irix 6 ABI has examples of this. */
1811 if (GET_CODE (reg) == PARALLEL)
1812 use_group_regs (call_fusage, reg);
1813 else if (nregs == -1)
1814 use_reg (call_fusage, reg);
1816 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1821 /* Try to integrate function. See expand_inline_function for documentation
1822 about the parameters. */
1825 try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1831 rtx structure_value_addr;
1836 rtx old_stack_level = 0;
1837 int reg_parm_stack_space = 0;
1839 #ifdef REG_PARM_STACK_SPACE
1840 #ifdef MAYBE_REG_PARM_STACK_SPACE
1841 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1843 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1847 before_call = get_last_insn ();
1849 timevar_push (TV_INTEGRATION);
1851 temp = expand_inline_function (fndecl, actparms, target,
1853 structure_value_addr);
1855 timevar_pop (TV_INTEGRATION);
1857 /* If inlining succeeded, return. */
1858 if (temp != (rtx) (size_t) - 1)
1860 if (ACCUMULATE_OUTGOING_ARGS)
1862 /* If the outgoing argument list must be preserved, push
1863 the stack before executing the inlined function if it
1866 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1867 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1870 if (stack_arg_under_construction || i >= 0)
1873 = before_call ? NEXT_INSN (before_call) : get_insns ();
1874 rtx insn = NULL_RTX, seq;
1876 /* Look for a call in the inline function code.
1877 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1878 nonzero then there is a call and it is not necessary
1879 to scan the insns. */
1881 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1882 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1883 if (GET_CODE (insn) == CALL_INSN)
1888 /* Reserve enough stack space so that the largest
1889 argument list of any function call in the inline
1890 function does not overlap the argument list being
1891 evaluated. This is usually an overestimate because
1892 allocate_dynamic_stack_space reserves space for an
1893 outgoing argument list in addition to the requested
1894 space, but there is no way to ask for stack space such
1895 that an argument list of a certain length can be
1898 Add the stack space reserved for register arguments, if
1899 any, in the inline function. What is really needed is the
1900 largest value of reg_parm_stack_space in the inline
1901 function, but that is not available. Using the current
1902 value of reg_parm_stack_space is wrong, but gives
1903 correct results on all supported machines. */
1905 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1906 + reg_parm_stack_space);
1909 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1910 allocate_dynamic_stack_space (GEN_INT (adjust),
1911 NULL_RTX, BITS_PER_UNIT);
1914 emit_insn_before (seq, first_insn);
1915 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1920 /* If the result is equivalent to TARGET, return TARGET to simplify
1921 checks in store_expr. They can be equivalent but not equal in the
1922 case of a function that returns BLKmode. */
1923 if (temp != target && rtx_equal_p (temp, target))
1928 /* If inlining failed, mark FNDECL as needing to be compiled
1929 separately after all. If function was declared inline,
1931 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1932 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1934 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1935 warning ("called from here");
1937 (*lang_hooks.mark_addressable) (fndecl);
1938 return (rtx) (size_t) - 1;
1941 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1942 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1943 bytes, then we would need to push some additional bytes to pad the
1944 arguments. So, we compute an adjust to the stack pointer for an
1945 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1946 bytes. Then, when the arguments are pushed the stack will be perfectly
1947 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1948 be popped after the call. Returns the adjustment. */
1951 combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1953 preferred_unit_stack_boundary)
1954 int unadjusted_args_size;
1955 struct args_size *args_size;
1956 int preferred_unit_stack_boundary;
1958 /* The number of bytes to pop so that the stack will be
1959 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1960 HOST_WIDE_INT adjustment;
1961 /* The alignment of the stack after the arguments are pushed, if we
1962 just pushed the arguments without adjust the stack here. */
1963 HOST_WIDE_INT unadjusted_alignment;
1965 unadjusted_alignment
1966 = ((stack_pointer_delta + unadjusted_args_size)
1967 % preferred_unit_stack_boundary);
1969 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1970 as possible -- leaving just enough left to cancel out the
1971 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1972 PENDING_STACK_ADJUST is non-negative, and congruent to
1973 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1975 /* Begin by trying to pop all the bytes. */
1976 unadjusted_alignment
1977 = (unadjusted_alignment
1978 - (pending_stack_adjust % preferred_unit_stack_boundary));
1979 adjustment = pending_stack_adjust;
1980 /* Push enough additional bytes that the stack will be aligned
1981 after the arguments are pushed. */
1982 if (preferred_unit_stack_boundary > 1)
1984 if (unadjusted_alignment > 0)
1985 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1987 adjustment += unadjusted_alignment;
1990 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1991 bytes after the call. The right number is the entire
1992 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1993 by the arguments in the first place. */
1995 = pending_stack_adjust - adjustment + unadjusted_args_size;
2000 /* Scan X expression if it does not dereference any argument slots
2001 we already clobbered by tail call arguments (as noted in stored_args_map
2003 Return nonzero if X expression dereferences such argument slots,
2007 check_sibcall_argument_overlap_1 (x)
2018 code = GET_CODE (x);
2022 if (XEXP (x, 0) == current_function_internal_arg_pointer)
2024 else if (GET_CODE (XEXP (x, 0)) == PLUS
2025 && XEXP (XEXP (x, 0), 0) ==
2026 current_function_internal_arg_pointer
2027 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
2028 i = INTVAL (XEXP (XEXP (x, 0), 1));
2032 #ifdef ARGS_GROW_DOWNWARD
2033 i = -i - GET_MODE_SIZE (GET_MODE (x));
2036 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
2037 if (i + k < stored_args_map->n_bits
2038 && TEST_BIT (stored_args_map, i + k))
2044 /* Scan all subexpressions. */
2045 fmt = GET_RTX_FORMAT (code);
2046 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2050 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2053 else if (*fmt == 'E')
2055 for (j = 0; j < XVECLEN (x, i); j++)
2056 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2063 /* Scan sequence after INSN if it does not dereference any argument slots
2064 we already clobbered by tail call arguments (as noted in stored_args_map
2065 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2066 Return nonzero if sequence after INSN dereferences such argument slots,
2070 check_sibcall_argument_overlap (insn, arg)
2072 struct arg_data *arg;
2076 if (insn == NULL_RTX)
2077 insn = get_insns ();
2079 insn = NEXT_INSN (insn);
2081 for (; insn; insn = NEXT_INSN (insn))
2083 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2086 #ifdef ARGS_GROW_DOWNWARD
2087 low = -arg->slot_offset.constant - arg->size.constant;
2089 low = arg->slot_offset.constant;
2092 for (high = low + arg->size.constant; low < high; low++)
2093 SET_BIT (stored_args_map, low);
2094 return insn != NULL_RTX;
2101 switch (unsafe_for_reeval (t))
2106 case 1: /* Mildly unsafe. */
2107 t = unsave_expr (t);
2110 case 2: /* Wildly unsafe. */
2112 tree var = build_decl (VAR_DECL, NULL_TREE,
2115 expand_expr (t, NULL_RTX, VOIDmode, EXPAND_NORMAL));
2126 /* Generate all the code for a function call
2127 and return an rtx for its value.
2128 Store the value in TARGET (specified as an rtx) if convenient.
2129 If the value is stored in TARGET then TARGET is returned.
2130 If IGNORE is nonzero, then we ignore the value of the function call. */
2133 expand_call (exp, target, ignore)
2138 /* Nonzero if we are currently expanding a call. */
2139 static int currently_expanding_call = 0;
2141 /* List of actual parameters. */
2142 tree actparms = TREE_OPERAND (exp, 1);
2143 /* RTX for the function to be called. */
2145 /* Sequence of insns to perform a tail recursive "call". */
2146 rtx tail_recursion_insns = NULL_RTX;
2147 /* Sequence of insns to perform a normal "call". */
2148 rtx normal_call_insns = NULL_RTX;
2149 /* Sequence of insns to perform a tail recursive "call". */
2150 rtx tail_call_insns = NULL_RTX;
2151 /* Data type of the function. */
2153 /* Declaration of the function being called,
2154 or 0 if the function is computed (not known by name). */
2157 int try_tail_call = 1;
2158 int try_tail_recursion = 1;
2161 /* Register in which non-BLKmode value will be returned,
2162 or 0 if no value or if value is BLKmode. */
2164 /* Address where we should return a BLKmode value;
2165 0 if value not BLKmode. */
2166 rtx structure_value_addr = 0;
2167 /* Nonzero if that address is being passed by treating it as
2168 an extra, implicit first parameter. Otherwise,
2169 it is passed by being copied directly into struct_value_rtx. */
2170 int structure_value_addr_parm = 0;
2171 /* Size of aggregate value wanted, or zero if none wanted
2172 or if we are using the non-reentrant PCC calling convention
2173 or expecting the value in registers. */
2174 HOST_WIDE_INT struct_value_size = 0;
2175 /* Nonzero if called function returns an aggregate in memory PCC style,
2176 by returning the address of where to find it. */
2177 int pcc_struct_value = 0;
2179 /* Number of actual parameters in this call, including struct value addr. */
2181 /* Number of named args. Args after this are anonymous ones
2182 and they must all go on the stack. */
2185 /* Vector of information about each argument.
2186 Arguments are numbered in the order they will be pushed,
2187 not the order they are written. */
2188 struct arg_data *args;
2190 /* Total size in bytes of all the stack-parms scanned so far. */
2191 struct args_size args_size;
2192 struct args_size adjusted_args_size;
2193 /* Size of arguments before any adjustments (such as rounding). */
2194 int unadjusted_args_size;
2195 /* Data on reg parms scanned so far. */
2196 CUMULATIVE_ARGS args_so_far;
2197 /* Nonzero if a reg parm has been scanned. */
2199 /* Nonzero if this is an indirect function call. */
2201 /* Nonzero if we must avoid push-insns in the args for this call.
2202 If stack space is allocated for register parameters, but not by the
2203 caller, then it is preallocated in the fixed part of the stack frame.
2204 So the entire argument block must then be preallocated (i.e., we
2205 ignore PUSH_ROUNDING in that case). */
2207 int must_preallocate = !PUSH_ARGS;
2209 /* Size of the stack reserved for parameter registers. */
2210 int reg_parm_stack_space = 0;
2212 /* Address of space preallocated for stack parms
2213 (on machines that lack push insns), or 0 if space not preallocated. */
2216 /* Mask of ECF_ flags. */
2218 /* Nonzero if this is a call to an inline function. */
2219 int is_integrable = 0;
2220 #ifdef REG_PARM_STACK_SPACE
2221 /* Define the boundary of the register parm stack space that needs to be
2223 int low_to_save = -1, high_to_save;
2224 rtx save_area = 0; /* Place that it is saved */
2227 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2228 char *initial_stack_usage_map = stack_usage_map;
2229 int old_stack_arg_under_construction = 0;
2231 rtx old_stack_level = 0;
2232 int old_pending_adj = 0;
2233 int old_inhibit_defer_pop = inhibit_defer_pop;
2234 int old_stack_allocated;
2236 tree p = TREE_OPERAND (exp, 0);
2237 tree addr = TREE_OPERAND (exp, 0);
2239 /* The alignment of the stack, in bits. */
2240 HOST_WIDE_INT preferred_stack_boundary;
2241 /* The alignment of the stack, in bytes. */
2242 HOST_WIDE_INT preferred_unit_stack_boundary;
2244 /* See if this is "nothrow" function call. */
2245 if (TREE_NOTHROW (exp))
2246 flags |= ECF_NOTHROW;
2248 /* See if we can find a DECL-node for the actual function.
2249 As a result, decide whether this is a call to an integrable function. */
2251 fndecl = get_callee_fndecl (exp);
2255 && fndecl != current_function_decl
2256 && DECL_INLINE (fndecl)
2257 && DECL_SAVED_INSNS (fndecl)
2258 && DECL_SAVED_INSNS (fndecl)->inlinable)
2260 else if (! TREE_ADDRESSABLE (fndecl))
2262 /* In case this function later becomes inlinable,
2263 record that there was already a non-inline call to it.
2265 Use abstraction instead of setting TREE_ADDRESSABLE
2267 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2270 warning_with_decl (fndecl, "can't inline call to `%s'");
2271 warning ("called from here");
2273 (*lang_hooks.mark_addressable) (fndecl);
2276 flags |= flags_from_decl_or_type (fndecl);
2279 /* If we don't have specific function to call, see if we have a
2280 attributes set in the type. */
2282 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2284 #ifdef REG_PARM_STACK_SPACE
2285 #ifdef MAYBE_REG_PARM_STACK_SPACE
2286 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2288 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2292 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2293 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2294 must_preallocate = 1;
2297 /* Warn if this value is an aggregate type,
2298 regardless of which calling convention we are using for it. */
2299 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2300 warning ("function call has aggregate value");
2302 /* Set up a place to return a structure. */
2304 /* Cater to broken compilers. */
2305 if (aggregate_value_p (exp))
2307 /* This call returns a big structure. */
2308 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
2310 #ifdef PCC_STATIC_STRUCT_RETURN
2312 pcc_struct_value = 1;
2313 /* Easier than making that case work right. */
2316 /* In case this is a static function, note that it has been
2318 if (! TREE_ADDRESSABLE (fndecl))
2319 (*lang_hooks.mark_addressable) (fndecl);
2323 #else /* not PCC_STATIC_STRUCT_RETURN */
2325 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2327 if (target && GET_CODE (target) == MEM)
2328 structure_value_addr = XEXP (target, 0);
2331 /* For variable-sized objects, we must be called with a target
2332 specified. If we were to allocate space on the stack here,
2333 we would have no way of knowing when to free it. */
2334 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2336 mark_temp_addr_taken (d);
2337 structure_value_addr = XEXP (d, 0);
2341 #endif /* not PCC_STATIC_STRUCT_RETURN */
2344 /* If called function is inline, try to integrate it. */
2348 rtx temp = try_to_integrate (fndecl, actparms, target,
2349 ignore, TREE_TYPE (exp),
2350 structure_value_addr);
2351 if (temp != (rtx) (size_t) - 1)
2355 /* Figure out the amount to which the stack should be aligned. */
2356 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2358 /* Operand 0 is a pointer-to-function; get the type of the function. */
2359 funtype = TREE_TYPE (addr);
2360 if (! POINTER_TYPE_P (funtype))
2362 funtype = TREE_TYPE (funtype);
2364 /* See if this is a call to a function that can return more than once
2365 or a call to longjmp or malloc. */
2366 flags |= special_function_p (fndecl, flags);
2368 if (flags & ECF_MAY_BE_ALLOCA)
2369 current_function_calls_alloca = 1;
2371 /* If struct_value_rtx is 0, it means pass the address
2372 as if it were an extra parameter. */
2373 if (structure_value_addr && struct_value_rtx == 0)
2375 /* If structure_value_addr is a REG other than
2376 virtual_outgoing_args_rtx, we can use always use it. If it
2377 is not a REG, we must always copy it into a register.
2378 If it is virtual_outgoing_args_rtx, we must copy it to another
2379 register in some cases. */
2380 rtx temp = (GET_CODE (structure_value_addr) != REG
2381 || (ACCUMULATE_OUTGOING_ARGS
2382 && stack_arg_under_construction
2383 && structure_value_addr == virtual_outgoing_args_rtx)
2384 ? copy_addr_to_reg (structure_value_addr)
2385 : structure_value_addr);
2388 = tree_cons (error_mark_node,
2389 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2392 structure_value_addr_parm = 1;
2395 /* Count the arguments and set NUM_ACTUALS. */
2396 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2399 /* Compute number of named args.
2400 Normally, don't include the last named arg if anonymous args follow.
2401 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2402 (If no anonymous args follow, the result of list_length is actually
2403 one too large. This is harmless.)
2405 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2406 zero, this machine will be able to place unnamed args that were
2407 passed in registers into the stack. So treat all args as named.
2408 This allows the insns emitting for a specific argument list to be
2409 independent of the function declaration.
2411 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2412 reliable way to pass unnamed args in registers, so we must force
2413 them into memory. */
2415 if ((STRICT_ARGUMENT_NAMING
2416 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2417 && TYPE_ARG_TYPES (funtype) != 0)
2419 = (list_length (TYPE_ARG_TYPES (funtype))
2420 /* Don't include the last named arg. */
2421 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2422 /* Count the struct value address, if it is passed as a parm. */
2423 + structure_value_addr_parm);
2425 /* If we know nothing, treat all args as named. */
2426 n_named_args = num_actuals;
2428 /* Start updating where the next arg would go.
2430 On some machines (such as the PA) indirect calls have a different
2431 calling convention than normal calls. The last argument in
2432 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2434 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
2436 /* Make a vector to hold all the information about each arg. */
2437 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
2438 memset ((char *) args, 0, num_actuals * sizeof (struct arg_data));
2440 /* Build up entries in the ARGS array, compute the size of the
2441 arguments into ARGS_SIZE, etc. */
2442 initialize_argument_information (num_actuals, args, &args_size,
2443 n_named_args, actparms, fndecl,
2444 &args_so_far, reg_parm_stack_space,
2445 &old_stack_level, &old_pending_adj,
2446 &must_preallocate, &flags);
2450 /* If this function requires a variable-sized argument list, don't
2451 try to make a cse'able block for this call. We may be able to
2452 do this eventually, but it is too complicated to keep track of
2453 what insns go in the cse'able block and which don't. */
2455 flags &= ~ECF_LIBCALL_BLOCK;
2456 must_preallocate = 1;
2459 /* Now make final decision about preallocating stack space. */
2460 must_preallocate = finalize_must_preallocate (must_preallocate,
2464 /* If the structure value address will reference the stack pointer, we
2465 must stabilize it. We don't need to do this if we know that we are
2466 not going to adjust the stack pointer in processing this call. */
2468 if (structure_value_addr
2469 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2470 || reg_mentioned_p (virtual_outgoing_args_rtx,
2471 structure_value_addr))
2473 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2474 structure_value_addr = copy_to_reg (structure_value_addr);
2476 /* Tail calls can make things harder to debug, and we're traditionally
2477 pushed these optimizations into -O2. Don't try if we're already
2478 expanding a call, as that means we're an argument. Don't try if
2479 there's cleanups, as we know there's code to follow the call.
2481 If rtx_equal_function_value_matters is false, that means we've
2482 finished with regular parsing. Which means that some of the
2483 machinery we use to generate tail-calls is no longer in place.
2484 This is most often true of sjlj-exceptions, which we couldn't
2485 tail-call to anyway. */
2487 if (currently_expanding_call++ != 0
2488 || !flag_optimize_sibling_calls
2489 || !rtx_equal_function_value_matters
2490 || any_pending_cleanups (1)
2492 try_tail_call = try_tail_recursion = 0;
2494 /* Tail recursion fails, when we are not dealing with recursive calls. */
2495 if (!try_tail_recursion
2496 || TREE_CODE (addr) != ADDR_EXPR
2497 || TREE_OPERAND (addr, 0) != current_function_decl)
2498 try_tail_recursion = 0;
2500 /* Rest of purposes for tail call optimizations to fail. */
2502 #ifdef HAVE_sibcall_epilogue
2503 !HAVE_sibcall_epilogue
2508 /* Doing sibling call optimization needs some work, since
2509 structure_value_addr can be allocated on the stack.
2510 It does not seem worth the effort since few optimizable
2511 sibling calls will return a structure. */
2512 || structure_value_addr != NULL_RTX
2513 /* If the register holding the address is a callee saved
2514 register, then we lose. We have no way to prevent that,
2515 so we only allow calls to named functions. */
2516 /* ??? This could be done by having the insn constraints
2517 use a register class that is all call-clobbered. Any
2518 reload insns generated to fix things up would appear
2519 before the sibcall_epilogue. */
2520 || fndecl == NULL_TREE
2521 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP | ECF_NORETURN))
2522 || !FUNCTION_OK_FOR_SIBCALL (fndecl)
2523 /* If this function requires more stack slots than the current
2524 function, we cannot change it into a sibling call. */
2525 || args_size.constant > current_function_args_size
2526 /* If the callee pops its own arguments, then it must pop exactly
2527 the same number of arguments as the current function. */
2528 || (RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2529 != RETURN_POPS_ARGS (current_function_decl,
2530 TREE_TYPE (current_function_decl),
2531 current_function_args_size))
2532 || !(*lang_hooks.decls.ok_for_sibcall) (fndecl))
2535 if (try_tail_call || try_tail_recursion)
2538 actparms = NULL_TREE;
2539 /* Ok, we're going to give the tail call the old college try.
2540 This means we're going to evaluate the function arguments
2541 up to three times. There are two degrees of badness we can
2542 encounter, those that can be unsaved and those that can't.
2543 (See unsafe_for_reeval commentary for details.)
2545 Generate a new argument list. Pass safe arguments through
2546 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2547 For hard badness, evaluate them now and put their resulting
2548 rtx in a temporary VAR_DECL.
2550 initialize_argument_information has ordered the array for the
2551 order to be pushed, and we must remember this when reconstructing
2552 the original argument order. */
2554 if (PUSH_ARGS_REVERSED)
2563 i = num_actuals - 1;
2567 for (; i != end; i += inc)
2569 args[i].tree_value = fix_unsafe_tree (args[i].tree_value);
2570 /* We need to build actparms for optimize_tail_recursion. We can
2571 safely trash away TREE_PURPOSE, since it is unused by this
2573 if (try_tail_recursion)
2574 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2576 /* Do the same for the function address if it is an expression. */
2578 addr = fix_unsafe_tree (addr);
2579 /* Expanding one of those dangerous arguments could have added
2580 cleanups, but otherwise give it a whirl. */
2581 if (any_pending_cleanups (1))
2582 try_tail_call = try_tail_recursion = 0;
2585 /* Generate a tail recursion sequence when calling ourselves. */
2587 if (try_tail_recursion)
2589 /* We want to emit any pending stack adjustments before the tail
2590 recursion "call". That way we know any adjustment after the tail
2591 recursion call can be ignored if we indeed use the tail recursion
2593 int save_pending_stack_adjust = pending_stack_adjust;
2594 int save_stack_pointer_delta = stack_pointer_delta;
2596 /* Emit any queued insns now; otherwise they would end up in
2597 only one of the alternates. */
2600 /* Use a new sequence to hold any RTL we generate. We do not even
2601 know if we will use this RTL yet. The final decision can not be
2602 made until after RTL generation for the entire function is
2605 /* If expanding any of the arguments creates cleanups, we can't
2606 do a tailcall. So, we'll need to pop the pending cleanups
2607 list. If, however, all goes well, and there are no cleanups
2608 then the call to expand_start_target_temps will have no
2610 expand_start_target_temps ();
2611 if (optimize_tail_recursion (actparms, get_last_insn ()))
2613 if (any_pending_cleanups (1))
2614 try_tail_call = try_tail_recursion = 0;
2616 tail_recursion_insns = get_insns ();
2618 expand_end_target_temps ();
2621 /* Restore the original pending stack adjustment for the sibling and
2622 normal call cases below. */
2623 pending_stack_adjust = save_pending_stack_adjust;
2624 stack_pointer_delta = save_stack_pointer_delta;
2627 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2629 /* A fork duplicates the profile information, and an exec discards
2630 it. We can't rely on fork/exec to be paired. So write out the
2631 profile information we have gathered so far, and clear it. */
2632 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2633 is subject to race conditions, just as with multithreaded
2636 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__bb_fork_func"),
2641 /* Ensure current function's preferred stack boundary is at least
2642 what we need. We don't have to increase alignment for recursive
2644 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2645 && fndecl != current_function_decl)
2646 cfun->preferred_stack_boundary = preferred_stack_boundary;
2648 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2650 function_call_count++;
2652 /* We want to make two insn chains; one for a sibling call, the other
2653 for a normal call. We will select one of the two chains after
2654 initial RTL generation is complete. */
2655 for (pass = 0; pass < 2; pass++)
2657 int sibcall_failure = 0;
2658 /* We want to emit any pending stack adjustments before the tail
2659 recursion "call". That way we know any adjustment after the tail
2660 recursion call can be ignored if we indeed use the tail recursion
2662 int save_pending_stack_adjust = 0;
2663 int save_stack_pointer_delta = 0;
2665 rtx before_call, next_arg_reg;
2669 if (! try_tail_call)
2672 /* Emit any queued insns now; otherwise they would end up in
2673 only one of the alternates. */
2676 /* State variables we need to save and restore between
2678 save_pending_stack_adjust = pending_stack_adjust;
2679 save_stack_pointer_delta = stack_pointer_delta;
2682 flags &= ~ECF_SIBCALL;
2684 flags |= ECF_SIBCALL;
2686 /* Other state variables that we must reinitialize each time
2687 through the loop (that are not initialized by the loop itself). */
2691 /* Start a new sequence for the normal call case.
2693 From this point on, if the sibling call fails, we want to set
2694 sibcall_failure instead of continuing the loop. */
2699 /* We know at this point that there are not currently any
2700 pending cleanups. If, however, in the process of evaluating
2701 the arguments we were to create some, we'll need to be
2702 able to get rid of them. */
2703 expand_start_target_temps ();
2706 /* Don't let pending stack adjusts add up to too much.
2707 Also, do all pending adjustments now if there is any chance
2708 this might be a call to alloca or if we are expanding a sibling
2709 call sequence or if we are calling a function that is to return
2710 with stack pointer depressed. */
2711 if (pending_stack_adjust >= 32
2712 || (pending_stack_adjust > 0
2713 && (flags & (ECF_MAY_BE_ALLOCA | ECF_SP_DEPRESSED)))
2715 do_pending_stack_adjust ();
2717 /* When calling a const function, we must pop the stack args right away,
2718 so that the pop is deleted or moved with the call. */
2719 if (pass && (flags & ECF_LIBCALL_BLOCK))
2722 #ifdef FINAL_REG_PARM_STACK_SPACE
2723 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2726 /* Precompute any arguments as needed. */
2728 precompute_arguments (flags, num_actuals, args);
2730 /* Now we are about to start emitting insns that can be deleted
2731 if a libcall is deleted. */
2732 if (pass && (flags & (ECF_LIBCALL_BLOCK | ECF_MALLOC)))
2735 adjusted_args_size = args_size;
2736 /* Compute the actual size of the argument block required. The variable
2737 and constant sizes must be combined, the size may have to be rounded,
2738 and there may be a minimum required size. When generating a sibcall
2739 pattern, do not round up, since we'll be re-using whatever space our
2741 unadjusted_args_size
2742 = compute_argument_block_size (reg_parm_stack_space,
2743 &adjusted_args_size,
2745 : preferred_stack_boundary));
2747 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2749 /* The argument block when performing a sibling call is the
2750 incoming argument block. */
2753 argblock = virtual_incoming_args_rtx;
2755 #ifdef STACK_GROWS_DOWNWARD
2756 = plus_constant (argblock, current_function_pretend_args_size);
2758 = plus_constant (argblock, -current_function_pretend_args_size);
2760 stored_args_map = sbitmap_alloc (args_size.constant);
2761 sbitmap_zero (stored_args_map);
2764 /* If we have no actual push instructions, or shouldn't use them,
2765 make space for all args right now. */
2766 else if (adjusted_args_size.var != 0)
2768 if (old_stack_level == 0)
2770 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2771 old_pending_adj = pending_stack_adjust;
2772 pending_stack_adjust = 0;
2773 /* stack_arg_under_construction says whether a stack arg is
2774 being constructed at the old stack level. Pushing the stack
2775 gets a clean outgoing argument block. */
2776 old_stack_arg_under_construction = stack_arg_under_construction;
2777 stack_arg_under_construction = 0;
2779 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2783 /* Note that we must go through the motions of allocating an argument
2784 block even if the size is zero because we may be storing args
2785 in the area reserved for register arguments, which may be part of
2788 int needed = adjusted_args_size.constant;
2790 /* Store the maximum argument space used. It will be pushed by
2791 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2794 if (needed > current_function_outgoing_args_size)
2795 current_function_outgoing_args_size = needed;
2797 if (must_preallocate)
2799 if (ACCUMULATE_OUTGOING_ARGS)
2801 /* Since the stack pointer will never be pushed, it is
2802 possible for the evaluation of a parm to clobber
2803 something we have already written to the stack.
2804 Since most function calls on RISC machines do not use
2805 the stack, this is uncommon, but must work correctly.
2807 Therefore, we save any area of the stack that was already
2808 written and that we are using. Here we set up to do this
2809 by making a new stack usage map from the old one. The
2810 actual save will be done by store_one_arg.
2812 Another approach might be to try to reorder the argument
2813 evaluations to avoid this conflicting stack usage. */
2815 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2816 /* Since we will be writing into the entire argument area,
2817 the map must be allocated for its entire size, not just
2818 the part that is the responsibility of the caller. */
2819 needed += reg_parm_stack_space;
2822 #ifdef ARGS_GROW_DOWNWARD
2823 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2826 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2830 = (char *) alloca (highest_outgoing_arg_in_use);
2832 if (initial_highest_arg_in_use)
2833 memcpy (stack_usage_map, initial_stack_usage_map,
2834 initial_highest_arg_in_use);
2836 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2837 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2838 (highest_outgoing_arg_in_use
2839 - initial_highest_arg_in_use));
2842 /* The address of the outgoing argument list must not be
2843 copied to a register here, because argblock would be left
2844 pointing to the wrong place after the call to
2845 allocate_dynamic_stack_space below. */
2847 argblock = virtual_outgoing_args_rtx;
2851 if (inhibit_defer_pop == 0)
2853 /* Try to reuse some or all of the pending_stack_adjust
2854 to get this space. */
2856 = (combine_pending_stack_adjustment_and_call
2857 (unadjusted_args_size,
2858 &adjusted_args_size,
2859 preferred_unit_stack_boundary));
2861 /* combine_pending_stack_adjustment_and_call computes
2862 an adjustment before the arguments are allocated.
2863 Account for them and see whether or not the stack
2864 needs to go up or down. */
2865 needed = unadjusted_args_size - needed;
2869 /* We're releasing stack space. */
2870 /* ??? We can avoid any adjustment at all if we're
2871 already aligned. FIXME. */
2872 pending_stack_adjust = -needed;
2873 do_pending_stack_adjust ();
2877 /* We need to allocate space. We'll do that in
2878 push_block below. */
2879 pending_stack_adjust = 0;
2882 /* Special case this because overhead of `push_block' in
2883 this case is non-trivial. */
2885 argblock = virtual_outgoing_args_rtx;
2887 argblock = push_block (GEN_INT (needed), 0, 0);
2889 /* We only really need to call `copy_to_reg' in the case
2890 where push insns are going to be used to pass ARGBLOCK
2891 to a function call in ARGS. In that case, the stack
2892 pointer changes value from the allocation point to the
2893 call point, and hence the value of
2894 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2895 as well always do it. */
2896 argblock = copy_to_reg (argblock);
2898 /* The save/restore code in store_one_arg handles all
2899 cases except one: a constructor call (including a C
2900 function returning a BLKmode struct) to initialize
2902 if (stack_arg_under_construction)
2904 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2905 rtx push_size = GEN_INT (reg_parm_stack_space
2906 + adjusted_args_size.constant);
2908 rtx push_size = GEN_INT (adjusted_args_size.constant);
2910 if (old_stack_level == 0)
2912 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2914 old_pending_adj = pending_stack_adjust;
2915 pending_stack_adjust = 0;
2916 /* stack_arg_under_construction says whether a stack
2917 arg is being constructed at the old stack level.
2918 Pushing the stack gets a clean outgoing argument
2920 old_stack_arg_under_construction
2921 = stack_arg_under_construction;
2922 stack_arg_under_construction = 0;
2923 /* Make a new map for the new argument list. */
2924 stack_usage_map = (char *)
2925 alloca (highest_outgoing_arg_in_use);
2926 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2927 highest_outgoing_arg_in_use = 0;
2929 allocate_dynamic_stack_space (push_size, NULL_RTX,
2932 /* If argument evaluation might modify the stack pointer,
2933 copy the address of the argument list to a register. */
2934 for (i = 0; i < num_actuals; i++)
2935 if (args[i].pass_on_stack)
2937 argblock = copy_addr_to_reg (argblock);
2944 compute_argument_addresses (args, argblock, num_actuals);
2946 /* If we push args individually in reverse order, perform stack alignment
2947 before the first push (the last arg). */
2948 if (PUSH_ARGS_REVERSED && argblock == 0
2949 && adjusted_args_size.constant != unadjusted_args_size)
2951 /* When the stack adjustment is pending, we get better code
2952 by combining the adjustments. */
2953 if (pending_stack_adjust
2954 && ! (flags & ECF_LIBCALL_BLOCK)
2955 && ! inhibit_defer_pop)
2957 pending_stack_adjust
2958 = (combine_pending_stack_adjustment_and_call
2959 (unadjusted_args_size,
2960 &adjusted_args_size,
2961 preferred_unit_stack_boundary));
2962 do_pending_stack_adjust ();
2964 else if (argblock == 0)
2965 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2966 - unadjusted_args_size));
2968 /* Now that the stack is properly aligned, pops can't safely
2969 be deferred during the evaluation of the arguments. */
2972 funexp = rtx_for_function_call (fndecl, addr);
2974 /* Figure out the register where the value, if any, will come back. */
2976 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2977 && ! structure_value_addr)
2979 if (pcc_struct_value)
2980 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2981 fndecl, (pass == 0));
2983 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2986 /* Precompute all register parameters. It isn't safe to compute anything
2987 once we have started filling any specific hard regs. */
2988 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2990 #ifdef REG_PARM_STACK_SPACE
2991 /* Save the fixed argument area if it's part of the caller's frame and
2992 is clobbered by argument setup for this call. */
2993 if (ACCUMULATE_OUTGOING_ARGS && pass)
2994 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2995 &low_to_save, &high_to_save);
2998 /* Now store (and compute if necessary) all non-register parms.
2999 These come before register parms, since they can require block-moves,
3000 which could clobber the registers used for register parms.
3001 Parms which have partial registers are not stored here,
3002 but we do preallocate space here if they want that. */
3004 for (i = 0; i < num_actuals; i++)
3005 if (args[i].reg == 0 || args[i].pass_on_stack)
3007 rtx before_arg = get_last_insn ();
3009 if (store_one_arg (&args[i], argblock, flags,
3010 adjusted_args_size.var != 0,
3011 reg_parm_stack_space)
3013 && check_sibcall_argument_overlap (before_arg,
3015 sibcall_failure = 1;
3018 /* If we have a parm that is passed in registers but not in memory
3019 and whose alignment does not permit a direct copy into registers,
3020 make a group of pseudos that correspond to each register that we
3022 if (STRICT_ALIGNMENT)
3023 store_unaligned_arguments_into_pseudos (args, num_actuals);
3025 /* Now store any partially-in-registers parm.
3026 This is the last place a block-move can happen. */
3028 for (i = 0; i < num_actuals; i++)
3029 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3031 rtx before_arg = get_last_insn ();
3033 if (store_one_arg (&args[i], argblock, flags,
3034 adjusted_args_size.var != 0,
3035 reg_parm_stack_space)
3037 && check_sibcall_argument_overlap (before_arg,
3039 sibcall_failure = 1;
3042 /* If we pushed args in forward order, perform stack alignment
3043 after pushing the last arg. */
3044 if (!PUSH_ARGS_REVERSED && argblock == 0)
3045 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3046 - unadjusted_args_size));
3048 /* If register arguments require space on the stack and stack space
3049 was not preallocated, allocate stack space here for arguments
3050 passed in registers. */
3051 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3052 if (!ACCUMULATE_OUTGOING_ARGS
3053 && must_preallocate == 0 && reg_parm_stack_space > 0)
3054 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3057 /* Pass the function the address in which to return a
3059 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3061 emit_move_insn (struct_value_rtx,
3063 force_operand (structure_value_addr,
3066 if (GET_CODE (struct_value_rtx) == REG)
3067 use_reg (&call_fusage, struct_value_rtx);
3070 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3071 reg_parm_seen, pass == 0);
3073 load_register_parameters (args, num_actuals, &call_fusage, flags);
3075 /* Perform postincrements before actually calling the function. */
3078 /* Save a pointer to the last insn before the call, so that we can
3079 later safely search backwards to find the CALL_INSN. */
3080 before_call = get_last_insn ();
3082 /* Set up next argument register. For sibling calls on machines
3083 with register windows this should be the incoming register. */
3084 #ifdef FUNCTION_INCOMING_ARG
3086 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3090 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3093 /* All arguments and registers used for the call must be set up by
3096 /* Stack must be properly aligned now. */
3097 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3100 /* Generate the actual call instruction. */
3101 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3102 adjusted_args_size.constant, struct_value_size,
3103 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3104 flags, & args_so_far);
3106 /* Verify that we've deallocated all the stack we used. */
3108 && ! (flags & (ECF_NORETURN | ECF_LONGJMP))
3109 && old_stack_allocated != stack_pointer_delta - pending_stack_adjust)
3112 /* If call is cse'able, make appropriate pair of reg-notes around it.
3113 Test valreg so we don't crash; may safely ignore `const'
3114 if return type is void. Disable for PARALLEL return values, because
3115 we have no way to move such values into a pseudo register. */
3116 if (pass && (flags & ECF_LIBCALL_BLOCK))
3120 if (valreg == 0 || GET_CODE (valreg) == PARALLEL)
3122 insns = get_insns ();
3129 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3131 /* Mark the return value as a pointer if needed. */
3132 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3133 mark_reg_pointer (temp,
3134 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3136 /* Construct an "equal form" for the value which mentions all the
3137 arguments in order as well as the function name. */
3138 for (i = 0; i < num_actuals; i++)
3139 note = gen_rtx_EXPR_LIST (VOIDmode,
3140 args[i].initial_value, note);
3141 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3143 insns = get_insns ();
3146 if (flags & ECF_PURE)
3147 note = gen_rtx_EXPR_LIST (VOIDmode,
3148 gen_rtx_USE (VOIDmode,
3149 gen_rtx_MEM (BLKmode,
3150 gen_rtx_SCRATCH (VOIDmode))),
3153 emit_libcall_block (insns, temp, valreg, note);
3158 else if (pass && (flags & ECF_MALLOC))
3160 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3163 /* The return value from a malloc-like function is a pointer. */
3164 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3165 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3167 emit_move_insn (temp, valreg);
3169 /* The return value from a malloc-like function can not alias
3171 last = get_last_insn ();
3173 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3175 /* Write out the sequence. */
3176 insns = get_insns ();
3182 /* For calls to `setjmp', etc., inform flow.c it should complain
3183 if nonvolatile values are live. For functions that cannot return,
3184 inform flow that control does not fall through. */
3186 if ((flags & (ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3188 /* The barrier must be emitted
3189 immediately after the CALL_INSN. Some ports emit more
3190 than just a CALL_INSN above, so we must search for it here. */
3192 rtx last = get_last_insn ();
3193 while (GET_CODE (last) != CALL_INSN)
3195 last = PREV_INSN (last);
3196 /* There was no CALL_INSN? */
3197 if (last == before_call)
3201 emit_barrier_after (last);
3203 /* Stack adjustments after a noreturn call are dead code. */
3204 stack_pointer_delta = old_stack_allocated;
3205 pending_stack_adjust = 0;
3208 if (flags & ECF_LONGJMP)
3209 current_function_calls_longjmp = 1;
3211 /* If this function is returning into a memory location marked as
3212 readonly, it means it is initializing that location. But we normally
3213 treat functions as not clobbering such locations, so we need to
3214 specify that this one does. */
3215 if (target != 0 && GET_CODE (target) == MEM
3216 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
3217 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
3219 /* If value type not void, return an rtx for the value. */
3221 /* If there are cleanups to be called, don't use a hard reg as target.
3222 We need to double check this and see if it matters anymore. */
3223 if (any_pending_cleanups (1))
3225 if (target && REG_P (target)
3226 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3228 sibcall_failure = 1;
3231 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3233 target = const0_rtx;
3234 else if (structure_value_addr)
3236 if (target == 0 || GET_CODE (target) != MEM)
3239 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3240 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3241 structure_value_addr));
3242 set_mem_attributes (target, exp, 1);
3245 else if (pcc_struct_value)
3247 /* This is the special C++ case where we need to
3248 know what the true target was. We take care to
3249 never use this value more than once in one expression. */
3250 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3251 copy_to_reg (valreg));
3252 set_mem_attributes (target, exp, 1);
3254 /* Handle calls that return values in multiple non-contiguous locations.
3255 The Irix 6 ABI has examples of this. */
3256 else if (GET_CODE (valreg) == PARALLEL)
3260 /* This will only be assigned once, so it can be readonly. */
3261 tree nt = build_qualified_type (TREE_TYPE (exp),
3262 (TYPE_QUALS (TREE_TYPE (exp))
3263 | TYPE_QUAL_CONST));
3265 target = assign_temp (nt, 0, 1, 1);
3266 preserve_temp_slots (target);
3269 if (! rtx_equal_p (target, valreg))
3270 emit_group_store (target, valreg,
3271 int_size_in_bytes (TREE_TYPE (exp)));
3273 /* We can not support sibling calls for this case. */
3274 sibcall_failure = 1;
3277 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3278 && GET_MODE (target) == GET_MODE (valreg))
3280 /* TARGET and VALREG cannot be equal at this point because the
3281 latter would not have REG_FUNCTION_VALUE_P true, while the
3282 former would if it were referring to the same register.
3284 If they refer to the same register, this move will be a no-op,
3285 except when function inlining is being done. */
3286 emit_move_insn (target, valreg);
3288 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3290 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3292 /* We can not support sibling calls for this case. */
3293 sibcall_failure = 1;
3296 target = copy_to_reg (valreg);
3298 #ifdef PROMOTE_FUNCTION_RETURN
3299 /* If we promoted this return value, make the proper SUBREG. TARGET
3300 might be const0_rtx here, so be careful. */
3301 if (GET_CODE (target) == REG
3302 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3303 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3305 tree type = TREE_TYPE (exp);
3306 int unsignedp = TREE_UNSIGNED (type);
3309 /* If we don't promote as expected, something is wrong. */
3310 if (GET_MODE (target)
3311 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3314 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3315 && GET_MODE_SIZE (GET_MODE (target))
3316 > GET_MODE_SIZE (TYPE_MODE (type)))
3318 offset = GET_MODE_SIZE (GET_MODE (target))
3319 - GET_MODE_SIZE (TYPE_MODE (type));
3320 if (! BYTES_BIG_ENDIAN)
3321 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3322 else if (! WORDS_BIG_ENDIAN)
3323 offset %= UNITS_PER_WORD;
3325 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3326 SUBREG_PROMOTED_VAR_P (target) = 1;
3327 SUBREG_PROMOTED_UNSIGNED_SET (target, unsignedp);
3331 /* If size of args is variable or this was a constructor call for a stack
3332 argument, restore saved stack-pointer value. */
3334 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3336 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3337 pending_stack_adjust = old_pending_adj;
3338 stack_arg_under_construction = old_stack_arg_under_construction;
3339 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3340 stack_usage_map = initial_stack_usage_map;
3341 sibcall_failure = 1;
3343 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3345 #ifdef REG_PARM_STACK_SPACE
3348 restore_fixed_argument_area (save_area, argblock,
3349 high_to_save, low_to_save);
3353 /* If we saved any argument areas, restore them. */
3354 for (i = 0; i < num_actuals; i++)
3355 if (args[i].save_area)
3357 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3359 = gen_rtx_MEM (save_mode,
3360 memory_address (save_mode,
3361 XEXP (args[i].stack_slot, 0)));
3363 if (save_mode != BLKmode)
3364 emit_move_insn (stack_area, args[i].save_area);
3366 emit_block_move (stack_area, args[i].save_area,
3367 GEN_INT (args[i].size.constant),
3368 BLOCK_OP_CALL_PARM);
3371 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3372 stack_usage_map = initial_stack_usage_map;
3375 /* If this was alloca, record the new stack level for nonlocal gotos.
3376 Check for the handler slots since we might not have a save area
3377 for non-local gotos. */
3379 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3380 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3382 /* Free up storage we no longer need. */
3383 for (i = 0; i < num_actuals; ++i)
3384 if (args[i].aligned_regs)
3385 free (args[i].aligned_regs);
3389 /* Undo the fake expand_start_target_temps we did earlier. If
3390 there had been any cleanups created, we've already set
3392 expand_end_target_temps ();
3395 insns = get_insns ();
3400 tail_call_insns = insns;
3402 /* Restore the pending stack adjustment now that we have
3403 finished generating the sibling call sequence. */
3405 pending_stack_adjust = save_pending_stack_adjust;
3406 stack_pointer_delta = save_stack_pointer_delta;
3408 /* Prepare arg structure for next iteration. */
3409 for (i = 0; i < num_actuals; i++)
3412 args[i].aligned_regs = 0;
3416 sbitmap_free (stored_args_map);
3419 normal_call_insns = insns;
3421 /* If something prevents making this a sibling call,
3422 zero out the sequence. */
3423 if (sibcall_failure)
3424 tail_call_insns = NULL_RTX;
3427 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3428 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3429 can happen if the arguments to this function call an inline
3430 function who's expansion contains another CALL_PLACEHOLDER.
3432 If there are any C_Ps in any of these sequences, replace them
3433 with their normal call. */
3435 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3436 if (GET_CODE (insn) == CALL_INSN
3437 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3438 replace_call_placeholder (insn, sibcall_use_normal);
3440 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3441 if (GET_CODE (insn) == CALL_INSN
3442 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3443 replace_call_placeholder (insn, sibcall_use_normal);
3445 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3446 if (GET_CODE (insn) == CALL_INSN
3447 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3448 replace_call_placeholder (insn, sibcall_use_normal);
3450 /* If this was a potential tail recursion site, then emit a
3451 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3452 One of them will be selected later. */
3453 if (tail_recursion_insns || tail_call_insns)
3455 /* The tail recursion label must be kept around. We could expose
3456 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3457 and makes determining true tail recursion sites difficult.
3459 So we set LABEL_PRESERVE_P here, then clear it when we select
3460 one of the call sequences after rtl generation is complete. */
3461 if (tail_recursion_insns)
3462 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3463 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3465 tail_recursion_insns,
3466 tail_recursion_label));
3469 emit_insn (normal_call_insns);
3471 currently_expanding_call--;
3473 /* If this function returns with the stack pointer depressed, ensure
3474 this block saves and restores the stack pointer, show it was
3475 changed, and adjust for any outgoing arg space. */
3476 if (flags & ECF_SP_DEPRESSED)
3478 clear_pending_stack_adjust ();
3479 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3480 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3481 save_stack_pointer ();
3487 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3488 The RETVAL parameter specifies whether return value needs to be saved, other
3489 parameters are documented in the emit_library_call function below. */
3492 emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3496 enum libcall_type fn_type;
3497 enum machine_mode outmode;
3501 /* Total size in bytes of all the stack-parms scanned so far. */
3502 struct args_size args_size;
3503 /* Size of arguments before any adjustments (such as rounding). */
3504 struct args_size original_args_size;
3509 struct args_size alignment_pad;
3511 CUMULATIVE_ARGS args_so_far;
3515 enum machine_mode mode;
3518 struct args_size offset;
3519 struct args_size size;
3523 int old_inhibit_defer_pop = inhibit_defer_pop;
3524 rtx call_fusage = 0;
3527 int pcc_struct_value = 0;
3528 int struct_value_size = 0;
3530 int reg_parm_stack_space = 0;
3533 tree tfom; /* type_for_mode (outmode, 0) */
3535 #ifdef REG_PARM_STACK_SPACE
3536 /* Define the boundary of the register parm stack space that needs to be
3538 int low_to_save = -1, high_to_save = 0;
3539 rtx save_area = 0; /* Place that it is saved. */
3542 /* Size of the stack reserved for parameter registers. */
3543 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3544 char *initial_stack_usage_map = stack_usage_map;
3546 #ifdef REG_PARM_STACK_SPACE
3547 #ifdef MAYBE_REG_PARM_STACK_SPACE
3548 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3550 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3554 /* By default, library functions can not throw. */
3555 flags = ECF_NOTHROW;
3567 case LCT_CONST_MAKE_BLOCK:
3568 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
3570 case LCT_PURE_MAKE_BLOCK:
3571 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
3574 flags |= ECF_NORETURN;
3577 flags = ECF_NORETURN;
3579 case LCT_ALWAYS_RETURN:
3580 flags = ECF_ALWAYS_RETURN;
3582 case LCT_RETURNS_TWICE:
3583 flags = ECF_RETURNS_TWICE;
3588 /* Ensure current function's preferred stack boundary is at least
3590 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3591 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3593 /* If this kind of value comes back in memory,
3594 decide where in memory it should come back. */
3595 if (outmode != VOIDmode)
3597 tfom = (*lang_hooks.types.type_for_mode) (outmode, 0);
3598 if (aggregate_value_p (tfom))
3600 #ifdef PCC_STATIC_STRUCT_RETURN
3602 = hard_function_value (build_pointer_type (tfom), 0, 0);
3603 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3604 pcc_struct_value = 1;
3606 value = gen_reg_rtx (outmode);
3607 #else /* not PCC_STATIC_STRUCT_RETURN */
3608 struct_value_size = GET_MODE_SIZE (outmode);
3609 if (value != 0 && GET_CODE (value) == MEM)
3612 mem_value = assign_temp (tfom, 0, 1, 1);
3614 /* This call returns a big structure. */
3615 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3619 tfom = void_type_node;
3621 /* ??? Unfinished: must pass the memory address as an argument. */
3623 /* Copy all the libcall-arguments out of the varargs data
3624 and into a vector ARGVEC.
3626 Compute how to pass each argument. We only support a very small subset
3627 of the full argument passing conventions to limit complexity here since
3628 library functions shouldn't have many args. */
3630 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3631 memset ((char *) argvec, 0, (nargs + 1) * sizeof (struct arg));
3633 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3634 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3636 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3639 args_size.constant = 0;
3644 /* Now we are about to start emitting insns that can be deleted
3645 if a libcall is deleted. */
3646 if (flags & ECF_LIBCALL_BLOCK)
3651 /* If there's a structure value address to be passed,
3652 either pass it in the special place, or pass it as an extra argument. */
3653 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3655 rtx addr = XEXP (mem_value, 0);
3658 /* Make sure it is a reasonable operand for a move or push insn. */
3659 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3660 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3661 addr = force_operand (addr, NULL_RTX);
3663 argvec[count].value = addr;
3664 argvec[count].mode = Pmode;
3665 argvec[count].partial = 0;
3667 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3668 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3669 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3673 locate_and_pad_parm (Pmode, NULL_TREE,
3674 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3677 argvec[count].reg != 0,
3679 NULL_TREE, &args_size, &argvec[count].offset,
3680 &argvec[count].size, &alignment_pad);
3682 if (argvec[count].reg == 0 || argvec[count].partial != 0
3683 || reg_parm_stack_space > 0)
3684 args_size.constant += argvec[count].size.constant;
3686 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3691 for (; count < nargs; count++)
3693 rtx val = va_arg (p, rtx);
3694 enum machine_mode mode = va_arg (p, enum machine_mode);
3696 /* We cannot convert the arg value to the mode the library wants here;
3697 must do it earlier where we know the signedness of the arg. */
3699 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3702 /* On some machines, there's no way to pass a float to a library fcn.
3703 Pass it as a double instead. */
3704 #ifdef LIBGCC_NEEDS_DOUBLE
3705 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3706 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3709 /* There's no need to call protect_from_queue, because
3710 either emit_move_insn or emit_push_insn will do that. */
3712 /* Make sure it is a reasonable operand for a move or push insn. */
3713 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3714 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3715 val = force_operand (val, NULL_RTX);
3717 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3718 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3722 #ifdef FUNCTION_ARG_CALLEE_COPIES
3723 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3728 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3729 functions, so we have to pretend this isn't such a function. */
3730 if (flags & ECF_LIBCALL_BLOCK)
3732 rtx insns = get_insns ();
3736 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3738 /* If this was a CONST function, it is now PURE since
3739 it now reads memory. */
3740 if (flags & ECF_CONST)
3742 flags &= ~ECF_CONST;
3746 if (GET_MODE (val) == MEM && ! must_copy)
3750 slot = assign_temp ((*lang_hooks.types.type_for_mode) (mode, 0),
3752 emit_move_insn (slot, val);
3756 tree type = (*lang_hooks.types.type_for_mode) (mode, 0);
3758 slot = gen_rtx_MEM (mode,
3759 expand_expr (build1 (ADDR_EXPR,
3762 make_tree (type, val)),
3763 NULL_RTX, VOIDmode, 0));
3766 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3767 gen_rtx_USE (VOIDmode, slot),
3770 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3771 gen_rtx_CLOBBER (VOIDmode,
3776 val = force_operand (XEXP (slot, 0), NULL_RTX);
3780 argvec[count].value = val;
3781 argvec[count].mode = mode;
3783 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3785 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3786 argvec[count].partial
3787 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3789 argvec[count].partial = 0;
3792 locate_and_pad_parm (mode, NULL_TREE,
3793 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3796 argvec[count].reg != 0,
3798 NULL_TREE, &args_size, &argvec[count].offset,
3799 &argvec[count].size, &alignment_pad);
3801 if (argvec[count].size.var)
3804 if (reg_parm_stack_space == 0 && argvec[count].partial)
3805 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3807 if (argvec[count].reg == 0 || argvec[count].partial != 0
3808 || reg_parm_stack_space > 0)
3809 args_size.constant += argvec[count].size.constant;
3811 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3814 #ifdef FINAL_REG_PARM_STACK_SPACE
3815 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3818 /* If this machine requires an external definition for library
3819 functions, write one out. */
3820 assemble_external_libcall (fun);
3822 original_args_size = args_size;
3823 args_size.constant = (((args_size.constant
3824 + stack_pointer_delta
3828 - stack_pointer_delta);
3830 args_size.constant = MAX (args_size.constant,
3831 reg_parm_stack_space);
3833 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3834 args_size.constant -= reg_parm_stack_space;
3837 if (args_size.constant > current_function_outgoing_args_size)
3838 current_function_outgoing_args_size = args_size.constant;
3840 if (ACCUMULATE_OUTGOING_ARGS)
3842 /* Since the stack pointer will never be pushed, it is possible for
3843 the evaluation of a parm to clobber something we have already
3844 written to the stack. Since most function calls on RISC machines
3845 do not use the stack, this is uncommon, but must work correctly.
3847 Therefore, we save any area of the stack that was already written
3848 and that we are using. Here we set up to do this by making a new
3849 stack usage map from the old one.
3851 Another approach might be to try to reorder the argument
3852 evaluations to avoid this conflicting stack usage. */
3854 needed = args_size.constant;
3856 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3857 /* Since we will be writing into the entire argument area, the
3858 map must be allocated for its entire size, not just the part that
3859 is the responsibility of the caller. */
3860 needed += reg_parm_stack_space;
3863 #ifdef ARGS_GROW_DOWNWARD
3864 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3867 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3870 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3872 if (initial_highest_arg_in_use)
3873 memcpy (stack_usage_map, initial_stack_usage_map,
3874 initial_highest_arg_in_use);
3876 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3877 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3878 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3881 /* We must be careful to use virtual regs before they're instantiated,
3882 and real regs afterwards. Loop optimization, for example, can create
3883 new libcalls after we've instantiated the virtual regs, and if we
3884 use virtuals anyway, they won't match the rtl patterns. */
3886 if (virtuals_instantiated)
3887 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
3889 argblock = virtual_outgoing_args_rtx;
3894 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3897 /* If we push args individually in reverse order, perform stack alignment
3898 before the first push (the last arg). */
3899 if (argblock == 0 && PUSH_ARGS_REVERSED)
3900 anti_adjust_stack (GEN_INT (args_size.constant
3901 - original_args_size.constant));
3903 if (PUSH_ARGS_REVERSED)
3914 #ifdef REG_PARM_STACK_SPACE
3915 if (ACCUMULATE_OUTGOING_ARGS)
3917 /* The argument list is the property of the called routine and it
3918 may clobber it. If the fixed area has been used for previous
3919 parameters, we must save and restore it.
3921 Here we compute the boundary of the that needs to be saved, if any. */
3923 #ifdef ARGS_GROW_DOWNWARD
3924 for (count = 0; count < reg_parm_stack_space + 1; count++)
3926 for (count = 0; count < reg_parm_stack_space; count++)
3929 if (count >= highest_outgoing_arg_in_use
3930 || stack_usage_map[count] == 0)
3933 if (low_to_save == -1)
3934 low_to_save = count;
3936 high_to_save = count;
3939 if (low_to_save >= 0)
3941 int num_to_save = high_to_save - low_to_save + 1;
3942 enum machine_mode save_mode
3943 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3946 /* If we don't have the required alignment, must do this in BLKmode. */
3947 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3948 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3949 save_mode = BLKmode;
3951 #ifdef ARGS_GROW_DOWNWARD
3952 stack_area = gen_rtx_MEM (save_mode,
3953 memory_address (save_mode,
3954 plus_constant (argblock,
3957 stack_area = gen_rtx_MEM (save_mode,
3958 memory_address (save_mode,
3959 plus_constant (argblock,
3962 if (save_mode == BLKmode)
3964 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3965 set_mem_align (save_area, PARM_BOUNDARY);
3966 emit_block_move (save_area, stack_area, GEN_INT (num_to_save),
3967 BLOCK_OP_CALL_PARM);
3971 save_area = gen_reg_rtx (save_mode);
3972 emit_move_insn (save_area, stack_area);
3978 /* Push the args that need to be pushed. */
3980 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3981 are to be pushed. */
3982 for (count = 0; count < nargs; count++, argnum += inc)
3984 enum machine_mode mode = argvec[argnum].mode;
3985 rtx val = argvec[argnum].value;
3986 rtx reg = argvec[argnum].reg;
3987 int partial = argvec[argnum].partial;
3988 int lower_bound = 0, upper_bound = 0, i;
3990 if (! (reg != 0 && partial == 0))
3992 if (ACCUMULATE_OUTGOING_ARGS)
3994 /* If this is being stored into a pre-allocated, fixed-size,
3995 stack area, save any previous data at that location. */
3997 #ifdef ARGS_GROW_DOWNWARD
3998 /* stack_slot is negative, but we want to index stack_usage_map
3999 with positive values. */
4000 upper_bound = -argvec[argnum].offset.constant + 1;
4001 lower_bound = upper_bound - argvec[argnum].size.constant;
4003 lower_bound = argvec[argnum].offset.constant;
4004 upper_bound = lower_bound + argvec[argnum].size.constant;
4007 for (i = lower_bound; i < upper_bound; i++)
4008 if (stack_usage_map[i]
4009 /* Don't store things in the fixed argument area at this
4010 point; it has already been saved. */
4011 && i > reg_parm_stack_space)
4014 if (i != upper_bound)
4016 /* We need to make a save area. See what mode we can make
4018 enum machine_mode save_mode
4019 = mode_for_size (argvec[argnum].size.constant
4027 plus_constant (argblock,
4028 argvec[argnum].offset.constant)));
4029 if (save_mode == BLKmode)
4031 argvec[argnum].save_area
4032 = assign_stack_temp (BLKmode,
4033 argvec[argnum].size.constant, 0);
4035 emit_block_move (validize_mem (argvec[argnum].save_area),
4037 GEN_INT (argvec[argnum].size.constant),
4038 BLOCK_OP_CALL_PARM);
4042 argvec[argnum].save_area = gen_reg_rtx (save_mode);
4044 emit_move_insn (argvec[argnum].save_area, stack_area);
4049 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, PARM_BOUNDARY,
4050 partial, reg, 0, argblock,
4051 GEN_INT (argvec[argnum].offset.constant),
4052 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
4054 /* Now mark the segment we just used. */
4055 if (ACCUMULATE_OUTGOING_ARGS)
4056 for (i = lower_bound; i < upper_bound; i++)
4057 stack_usage_map[i] = 1;
4063 /* If we pushed args in forward order, perform stack alignment
4064 after pushing the last arg. */
4065 if (argblock == 0 && !PUSH_ARGS_REVERSED)
4066 anti_adjust_stack (GEN_INT (args_size.constant
4067 - original_args_size.constant));
4069 if (PUSH_ARGS_REVERSED)
4074 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0, 0);
4076 /* Now load any reg parms into their regs. */
4078 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4079 are to be pushed. */
4080 for (count = 0; count < nargs; count++, argnum += inc)
4082 rtx val = argvec[argnum].value;
4083 rtx reg = argvec[argnum].reg;
4084 int partial = argvec[argnum].partial;
4086 /* Handle calls that pass values in multiple non-contiguous
4087 locations. The PA64 has examples of this for library calls. */
4088 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4089 emit_group_load (reg, val, GET_MODE_SIZE (GET_MODE (val)));
4090 else if (reg != 0 && partial == 0)
4091 emit_move_insn (reg, val);
4096 /* Any regs containing parms remain in use through the call. */
4097 for (count = 0; count < nargs; count++)
4099 rtx reg = argvec[count].reg;
4100 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4101 use_group_regs (&call_fusage, reg);
4103 use_reg (&call_fusage, reg);
4106 /* Pass the function the address in which to return a structure value. */
4107 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
4109 emit_move_insn (struct_value_rtx,
4111 force_operand (XEXP (mem_value, 0),
4113 if (GET_CODE (struct_value_rtx) == REG)
4114 use_reg (&call_fusage, struct_value_rtx);
4117 /* Don't allow popping to be deferred, since then
4118 cse'ing of library calls could delete a call and leave the pop. */
4120 valreg = (mem_value == 0 && outmode != VOIDmode
4121 ? hard_libcall_value (outmode) : NULL_RTX);
4123 /* Stack must be properly aligned now. */
4124 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4127 before_call = get_last_insn ();
4129 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4130 will set inhibit_defer_pop to that value. */
4131 /* The return type is needed to decide how many bytes the function pops.
4132 Signedness plays no role in that, so for simplicity, we pretend it's
4133 always signed. We also assume that the list of arguments passed has
4134 no impact, so we pretend it is unknown. */
4137 get_identifier (XSTR (orgfun, 0)),
4138 build_function_type (tfom, NULL_TREE),
4139 original_args_size.constant, args_size.constant,
4141 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4143 old_inhibit_defer_pop + 1, call_fusage, flags, & args_so_far);
4145 /* For calls to `setjmp', etc., inform flow.c it should complain
4146 if nonvolatile values are live. For functions that cannot return,
4147 inform flow that control does not fall through. */
4149 if (flags & (ECF_NORETURN | ECF_LONGJMP))
4151 /* The barrier note must be emitted
4152 immediately after the CALL_INSN. Some ports emit more than
4153 just a CALL_INSN above, so we must search for it here. */
4155 rtx last = get_last_insn ();
4156 while (GET_CODE (last) != CALL_INSN)
4158 last = PREV_INSN (last);
4159 /* There was no CALL_INSN? */
4160 if (last == before_call)
4164 emit_barrier_after (last);
4167 /* Now restore inhibit_defer_pop to its actual original value. */
4170 /* If call is cse'able, make appropriate pair of reg-notes around it.
4171 Test valreg so we don't crash; may safely ignore `const'
4172 if return type is void. Disable for PARALLEL return values, because
4173 we have no way to move such values into a pseudo register. */
4174 if (flags & ECF_LIBCALL_BLOCK)
4180 insns = get_insns ();
4190 if (GET_CODE (valreg) == PARALLEL)
4192 temp = gen_reg_rtx (outmode);
4193 emit_group_store (temp, valreg, outmode);
4197 temp = gen_reg_rtx (GET_MODE (valreg));
4199 /* Construct an "equal form" for the value which mentions all the
4200 arguments in order as well as the function name. */
4201 for (i = 0; i < nargs; i++)
4202 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4203 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4205 insns = get_insns ();
4208 if (flags & ECF_PURE)
4209 note = gen_rtx_EXPR_LIST (VOIDmode,
4210 gen_rtx_USE (VOIDmode,
4211 gen_rtx_MEM (BLKmode,
4212 gen_rtx_SCRATCH (VOIDmode))),
4215 emit_libcall_block (insns, temp, valreg, note);
4222 /* Copy the value to the right place. */
4223 if (outmode != VOIDmode && retval)
4229 if (value != mem_value)
4230 emit_move_insn (value, mem_value);
4232 else if (GET_CODE (valreg) == PARALLEL)
4235 value = gen_reg_rtx (outmode);
4236 emit_group_store (value, valreg, outmode);
4238 else if (value != 0)
4239 emit_move_insn (value, valreg);
4244 if (ACCUMULATE_OUTGOING_ARGS)
4246 #ifdef REG_PARM_STACK_SPACE
4249 enum machine_mode save_mode = GET_MODE (save_area);
4250 #ifdef ARGS_GROW_DOWNWARD
4252 = gen_rtx_MEM (save_mode,
4253 memory_address (save_mode,
4254 plus_constant (argblock,
4258 = gen_rtx_MEM (save_mode,
4259 memory_address (save_mode,
4260 plus_constant (argblock, low_to_save)));
4263 set_mem_align (stack_area, PARM_BOUNDARY);
4264 if (save_mode != BLKmode)
4265 emit_move_insn (stack_area, save_area);
4267 emit_block_move (stack_area, save_area,
4268 GEN_INT (high_to_save - low_to_save + 1),
4269 BLOCK_OP_CALL_PARM);
4273 /* If we saved any argument areas, restore them. */
4274 for (count = 0; count < nargs; count++)
4275 if (argvec[count].save_area)
4277 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4279 = gen_rtx_MEM (save_mode,
4282 plus_constant (argblock,
4283 argvec[count].offset.constant)));
4285 if (save_mode == BLKmode)
4286 emit_block_move (stack_area,
4287 validize_mem (argvec[count].save_area),
4288 GEN_INT (argvec[count].size.constant),
4289 BLOCK_OP_CALL_PARM);
4291 emit_move_insn (stack_area, argvec[count].save_area);
4294 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4295 stack_usage_map = initial_stack_usage_map;
4302 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4303 (emitting the queue unless NO_QUEUE is nonzero),
4304 for a value of mode OUTMODE,
4305 with NARGS different arguments, passed as alternating rtx values
4306 and machine_modes to convert them to.
4307 The rtx values should have been passed through protect_from_queue already.
4309 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4310 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4311 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4312 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4313 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4314 or other LCT_ value for other types of library calls. */
4317 emit_library_call VPARAMS((rtx orgfun, enum libcall_type fn_type,
4318 enum machine_mode outmode, int nargs, ...))
4321 VA_FIXEDARG (p, rtx, orgfun);
4322 VA_FIXEDARG (p, int, fn_type);
4323 VA_FIXEDARG (p, enum machine_mode, outmode);
4324 VA_FIXEDARG (p, int, nargs);
4326 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4331 /* Like emit_library_call except that an extra argument, VALUE,
4332 comes second and says where to store the result.
4333 (If VALUE is zero, this function chooses a convenient way
4334 to return the value.
4336 This function returns an rtx for where the value is to be found.
4337 If VALUE is nonzero, VALUE is returned. */
4340 emit_library_call_value VPARAMS((rtx orgfun, rtx value,
4341 enum libcall_type fn_type,
4342 enum machine_mode outmode, int nargs, ...))
4347 VA_FIXEDARG (p, rtx, orgfun);
4348 VA_FIXEDARG (p, rtx, value);
4349 VA_FIXEDARG (p, int, fn_type);
4350 VA_FIXEDARG (p, enum machine_mode, outmode);
4351 VA_FIXEDARG (p, int, nargs);
4353 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4361 /* Store a single argument for a function call
4362 into the register or memory area where it must be passed.
4363 *ARG describes the argument value and where to pass it.
4365 ARGBLOCK is the address of the stack-block for all the arguments,
4366 or 0 on a machine where arguments are pushed individually.
4368 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4369 so must be careful about how the stack is used.
4371 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4372 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4373 that we need not worry about saving and restoring the stack.
4375 FNDECL is the declaration of the function we are calling.
4377 Return nonzero if this arg should cause sibcall failure,
4381 store_one_arg (arg, argblock, flags, variable_size, reg_parm_stack_space)
4382 struct arg_data *arg;
4385 int variable_size ATTRIBUTE_UNUSED;
4386 int reg_parm_stack_space;
4388 tree pval = arg->tree_value;
4392 int i, lower_bound = 0, upper_bound = 0;
4393 int sibcall_failure = 0;
4395 if (TREE_CODE (pval) == ERROR_MARK)
4398 /* Push a new temporary level for any temporaries we make for
4402 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4404 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4405 save any previous data at that location. */
4406 if (argblock && ! variable_size && arg->stack)
4408 #ifdef ARGS_GROW_DOWNWARD
4409 /* stack_slot is negative, but we want to index stack_usage_map
4410 with positive values. */
4411 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4412 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4416 lower_bound = upper_bound - arg->size.constant;
4418 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4419 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4423 upper_bound = lower_bound + arg->size.constant;
4426 for (i = lower_bound; i < upper_bound; i++)
4427 if (stack_usage_map[i]
4428 /* Don't store things in the fixed argument area at this point;
4429 it has already been saved. */
4430 && i > reg_parm_stack_space)
4433 if (i != upper_bound)
4435 /* We need to make a save area. See what mode we can make it. */
4436 enum machine_mode save_mode
4437 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
4439 = gen_rtx_MEM (save_mode,
4440 memory_address (save_mode,
4441 XEXP (arg->stack_slot, 0)));
4443 if (save_mode == BLKmode)
4445 tree ot = TREE_TYPE (arg->tree_value);
4446 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4447 | TYPE_QUAL_CONST));
4449 arg->save_area = assign_temp (nt, 0, 1, 1);
4450 preserve_temp_slots (arg->save_area);
4451 emit_block_move (validize_mem (arg->save_area), stack_area,
4452 expr_size (arg->tree_value),
4453 BLOCK_OP_CALL_PARM);
4457 arg->save_area = gen_reg_rtx (save_mode);
4458 emit_move_insn (arg->save_area, stack_area);
4464 /* If this isn't going to be placed on both the stack and in registers,
4465 set up the register and number of words. */
4466 if (! arg->pass_on_stack)
4468 if (flags & ECF_SIBCALL)
4469 reg = arg->tail_call_reg;
4472 partial = arg->partial;
4475 if (reg != 0 && partial == 0)
4476 /* Being passed entirely in a register. We shouldn't be called in
4480 /* If this arg needs special alignment, don't load the registers
4482 if (arg->n_aligned_regs != 0)
4485 /* If this is being passed partially in a register, we can't evaluate
4486 it directly into its stack slot. Otherwise, we can. */
4487 if (arg->value == 0)
4489 /* stack_arg_under_construction is nonzero if a function argument is
4490 being evaluated directly into the outgoing argument list and
4491 expand_call must take special action to preserve the argument list
4492 if it is called recursively.
4494 For scalar function arguments stack_usage_map is sufficient to
4495 determine which stack slots must be saved and restored. Scalar
4496 arguments in general have pass_on_stack == 0.
4498 If this argument is initialized by a function which takes the
4499 address of the argument (a C++ constructor or a C function
4500 returning a BLKmode structure), then stack_usage_map is
4501 insufficient and expand_call must push the stack around the
4502 function call. Such arguments have pass_on_stack == 1.
4504 Note that it is always safe to set stack_arg_under_construction,
4505 but this generates suboptimal code if set when not needed. */
4507 if (arg->pass_on_stack)
4508 stack_arg_under_construction++;
4510 arg->value = expand_expr (pval,
4512 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4513 ? NULL_RTX : arg->stack,
4514 VOIDmode, EXPAND_STACK_PARM);
4516 /* If we are promoting object (or for any other reason) the mode
4517 doesn't agree, convert the mode. */
4519 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4520 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4521 arg->value, arg->unsignedp);
4523 if (arg->pass_on_stack)
4524 stack_arg_under_construction--;
4527 /* Don't allow anything left on stack from computation
4528 of argument to alloca. */
4529 if (flags & ECF_MAY_BE_ALLOCA)
4530 do_pending_stack_adjust ();
4532 if (arg->value == arg->stack)
4533 /* If the value is already in the stack slot, we are done. */
4535 else if (arg->mode != BLKmode)
4539 /* Argument is a scalar, not entirely passed in registers.
4540 (If part is passed in registers, arg->partial says how much
4541 and emit_push_insn will take care of putting it there.)
4543 Push it, and if its size is less than the
4544 amount of space allocated to it,
4545 also bump stack pointer by the additional space.
4546 Note that in C the default argument promotions
4547 will prevent such mismatches. */
4549 size = GET_MODE_SIZE (arg->mode);
4550 /* Compute how much space the push instruction will push.
4551 On many machines, pushing a byte will advance the stack
4552 pointer by a halfword. */
4553 #ifdef PUSH_ROUNDING
4554 size = PUSH_ROUNDING (size);
4558 /* Compute how much space the argument should get:
4559 round up to a multiple of the alignment for arguments. */
4560 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4561 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4562 / (PARM_BOUNDARY / BITS_PER_UNIT))
4563 * (PARM_BOUNDARY / BITS_PER_UNIT));
4565 /* This isn't already where we want it on the stack, so put it there.
4566 This can either be done with push or copy insns. */
4567 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4568 PARM_BOUNDARY, partial, reg, used - size, argblock,
4569 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4570 ARGS_SIZE_RTX (arg->alignment_pad));
4572 /* Unless this is a partially-in-register argument, the argument is now
4575 arg->value = arg->stack;
4579 /* BLKmode, at least partly to be pushed. */
4581 unsigned int parm_align;
4585 /* Pushing a nonscalar.
4586 If part is passed in registers, PARTIAL says how much
4587 and emit_push_insn will take care of putting it there. */
4589 /* Round its size up to a multiple
4590 of the allocation unit for arguments. */
4592 if (arg->size.var != 0)
4595 size_rtx = ARGS_SIZE_RTX (arg->size);
4599 /* PUSH_ROUNDING has no effect on us, because
4600 emit_push_insn for BLKmode is careful to avoid it. */
4601 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4602 + partial * UNITS_PER_WORD);
4603 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4604 NULL_RTX, TYPE_MODE (sizetype), 0);
4607 /* Some types will require stricter alignment, which will be
4608 provided for elsewhere in argument layout. */
4609 parm_align = MAX (PARM_BOUNDARY, TYPE_ALIGN (TREE_TYPE (pval)));
4611 /* When an argument is padded down, the block is aligned to
4612 PARM_BOUNDARY, but the actual argument isn't. */
4613 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4616 parm_align = BITS_PER_UNIT;
4619 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4620 parm_align = MIN (parm_align, excess_align);
4624 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4626 /* emit_push_insn might not work properly if arg->value and
4627 argblock + arg->offset areas overlap. */
4631 if (XEXP (x, 0) == current_function_internal_arg_pointer
4632 || (GET_CODE (XEXP (x, 0)) == PLUS
4633 && XEXP (XEXP (x, 0), 0) ==
4634 current_function_internal_arg_pointer
4635 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4637 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4638 i = INTVAL (XEXP (XEXP (x, 0), 1));
4640 /* expand_call should ensure this */
4641 if (arg->offset.var || GET_CODE (size_rtx) != CONST_INT)
4644 if (arg->offset.constant > i)
4646 if (arg->offset.constant < i + INTVAL (size_rtx))
4647 sibcall_failure = 1;
4649 else if (arg->offset.constant < i)
4651 if (i < arg->offset.constant + INTVAL (size_rtx))
4652 sibcall_failure = 1;
4657 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4658 parm_align, partial, reg, excess, argblock,
4659 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4660 ARGS_SIZE_RTX (arg->alignment_pad));
4662 /* Unless this is a partially-in-register argument, the argument is now
4665 ??? Unlike the case above, in which we want the actual
4666 address of the data, so that we can load it directly into a
4667 register, here we want the address of the stack slot, so that
4668 it's properly aligned for word-by-word copying or something
4669 like that. It's not clear that this is always correct. */
4671 arg->value = arg->stack_slot;
4674 /* Mark all slots this store used. */
4675 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
4676 && argblock && ! variable_size && arg->stack)
4677 for (i = lower_bound; i < upper_bound; i++)
4678 stack_usage_map[i] = 1;
4680 /* Once we have pushed something, pops can't safely
4681 be deferred during the rest of the arguments. */
4684 /* ANSI doesn't require a sequence point here,
4685 but PCC has one, so this will avoid some problems. */
4688 /* Free any temporary slots made in processing this argument. Show
4689 that we might have taken the address of something and pushed that
4691 preserve_temp_slots (NULL_RTX);
4695 return sibcall_failure;