1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998
3 1999, 2000 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
30 #include "insn-flags.h"
37 #ifndef ACCUMULATE_OUTGOING_ARGS
38 #define ACCUMULATE_OUTGOING_ARGS 0
41 /* Supply a default definition for PUSH_ARGS. */
44 #define PUSH_ARGS !ACCUMULATE_OUTGOING_ARGS
50 #if !defined FUNCTION_OK_FOR_SIBCALL
51 #define FUNCTION_OK_FOR_SIBCALL(DECL) 1
54 #if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY
55 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
58 /* Decide whether a function's arguments should be processed
59 from first to last or from last to first.
61 They should if the stack and args grow in opposite directions, but
62 only if we have push insns. */
66 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
67 #define PUSH_ARGS_REVERSED PUSH_ARGS
72 #ifndef PUSH_ARGS_REVERSED
73 #define PUSH_ARGS_REVERSED 0
76 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
77 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
79 /* Data structure and subroutines used within expand_call. */
83 /* Tree node for this argument. */
85 /* Mode for value; TYPE_MODE unless promoted. */
86 enum machine_mode mode;
87 /* Current RTL value for argument, or 0 if it isn't precomputed. */
89 /* Initially-compute RTL value for argument; only for const functions. */
91 /* Register to pass this argument in, 0 if passed on stack, or an
92 PARALLEL if the arg is to be copied into multiple non-contiguous
95 /* Register to pass this argument in when generating tail call sequence.
96 This is not the same register as for normal calls on machines with
99 /* If REG was promoted from the actual mode of the argument expression,
100 indicates whether the promotion is sign- or zero-extended. */
102 /* Number of registers to use. 0 means put the whole arg in registers.
103 Also 0 if not passed in registers. */
105 /* Non-zero if argument must be passed on stack.
106 Note that some arguments may be passed on the stack
107 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
108 pass_on_stack identifies arguments that *cannot* go in registers. */
110 /* Offset of this argument from beginning of stack-args. */
111 struct args_size offset;
112 /* Similar, but offset to the start of the stack slot. Different from
113 OFFSET if this arg pads downward. */
114 struct args_size slot_offset;
115 /* Size of this argument on the stack, rounded up for any padding it gets,
116 parts of the argument passed in registers do not count.
117 If REG_PARM_STACK_SPACE is defined, then register parms
118 are counted here as well. */
119 struct args_size size;
120 /* Location on the stack at which parameter should be stored. The store
121 has already been done if STACK == VALUE. */
123 /* Location on the stack of the start of this argument slot. This can
124 differ from STACK if this arg pads downward. This location is known
125 to be aligned to FUNCTION_ARG_BOUNDARY. */
127 /* Place that this stack area has been saved, if needed. */
129 /* If an argument's alignment does not permit direct copying into registers,
130 copy in smaller-sized pieces into pseudos. These are stored in a
131 block pointed to by this field. The next field says how many
132 word-sized pseudos we made. */
135 /* The amount that the stack pointer needs to be adjusted to
136 force alignment for the next argument. */
137 struct args_size alignment_pad;
140 /* A vector of one char per byte of stack space. A byte if non-zero if
141 the corresponding stack location has been used.
142 This vector is used to prevent a function call within an argument from
143 clobbering any stack already set up. */
144 static char *stack_usage_map;
146 /* Size of STACK_USAGE_MAP. */
147 static int highest_outgoing_arg_in_use;
149 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
150 stack location's tail call argument has been already stored into the stack.
151 This bitmap is used to prevent sibling call optimization if function tries
152 to use parent's incoming argument slots when they have been already
153 overwritten with tail call arguments. */
154 static sbitmap stored_args_map;
156 /* stack_arg_under_construction is nonzero when an argument may be
157 initialized with a constructor call (including a C function that
158 returns a BLKmode struct) and expand_call must take special action
159 to make sure the object being constructed does not overlap the
160 argument list for the constructor call. */
161 int stack_arg_under_construction;
163 static int calls_function PARAMS ((tree, int));
164 static int calls_function_1 PARAMS ((tree, int));
166 /* Nonzero if this is a call to a `const' function. */
168 /* Nonzero if this is a call to a `volatile' function. */
169 #define ECF_NORETURN 2
170 /* Nonzero if this is a call to malloc or a related function. */
172 /* Nonzero if it is plausible that this is a call to alloca. */
173 #define ECF_MAY_BE_ALLOCA 8
174 /* Nonzero if this is a call to a function that won't throw an exception. */
175 #define ECF_NOTHROW 16
176 /* Nonzero if this is a call to setjmp or a related function. */
177 #define ECF_RETURNS_TWICE 32
178 /* Nonzero if this is a call to `longjmp'. */
179 #define ECF_LONGJMP 64
180 /* Nonzero if this is a syscall that makes a new process in the image of
182 #define ECF_FORK_OR_EXEC 128
183 #define ECF_SIBCALL 256
184 /* Nonzero if this is a call to "pure" function (like const function,
185 but may read memory. */
187 /* Nonzero if this is a call to a function that returns with the stack
188 pointer depressed. */
189 #define ECF_SP_DEPRESSED 1024
191 static void emit_call_1 PARAMS ((rtx, tree, tree, HOST_WIDE_INT,
192 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
193 rtx, int, rtx, int));
194 static void precompute_register_parameters PARAMS ((int,
197 static int store_one_arg PARAMS ((struct arg_data *, rtx, int, int,
199 static void store_unaligned_arguments_into_pseudos PARAMS ((struct arg_data *,
201 static int finalize_must_preallocate PARAMS ((int, int,
203 struct args_size *));
204 static void precompute_arguments PARAMS ((int, int,
206 static int compute_argument_block_size PARAMS ((int,
209 static void initialize_argument_information PARAMS ((int,
216 static void compute_argument_addresses PARAMS ((struct arg_data *,
218 static rtx rtx_for_function_call PARAMS ((tree, tree));
219 static void load_register_parameters PARAMS ((struct arg_data *,
221 static int libfunc_nothrow PARAMS ((rtx));
222 static rtx emit_library_call_value_1 PARAMS ((int, rtx, rtx, int,
225 static int special_function_p PARAMS ((tree, int));
226 static int flags_from_decl_or_type PARAMS ((tree));
227 static rtx try_to_integrate PARAMS ((tree, tree, rtx,
229 static int check_sibcall_argument_overlap_1 PARAMS ((rtx));
230 static int check_sibcall_argument_overlap PARAMS ((rtx, struct arg_data *));
232 static int combine_pending_stack_adjustment_and_call
233 PARAMS ((int, struct args_size *, int));
235 #ifdef REG_PARM_STACK_SPACE
236 static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
237 static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
240 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
243 If WHICH is 0, return 1 if EXP contains a call to any function.
244 Actually, we only need return 1 if evaluating EXP would require pushing
245 arguments on the stack, but that is too difficult to compute, so we just
246 assume any function call might require the stack. */
248 static tree calls_function_save_exprs;
251 calls_function (exp, which)
257 calls_function_save_exprs = 0;
258 val = calls_function_1 (exp, which);
259 calls_function_save_exprs = 0;
263 /* Recursive function to do the work of above function. */
266 calls_function_1 (exp, which)
271 enum tree_code code = TREE_CODE (exp);
272 int class = TREE_CODE_CLASS (code);
273 int length = first_rtl_op (code);
275 /* If this code is language-specific, we don't know what it will do. */
276 if ((int) code >= NUM_TREE_CODES)
284 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
286 && (TYPE_RETURNS_STACK_DEPRESSED
287 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))))
289 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
290 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
292 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
294 & ECF_MAY_BE_ALLOCA))
300 if (SAVE_EXPR_RTL (exp) != 0)
302 if (value_member (exp, calls_function_save_exprs))
304 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
305 calls_function_save_exprs);
306 return (TREE_OPERAND (exp, 0) != 0
307 && calls_function_1 (TREE_OPERAND (exp, 0), which));
312 register tree subblock;
314 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
315 if (DECL_INITIAL (local) != 0
316 && calls_function_1 (DECL_INITIAL (local), which))
319 for (subblock = BLOCK_SUBBLOCKS (exp);
321 subblock = TREE_CHAIN (subblock))
322 if (calls_function_1 (subblock, which))
328 for (; exp != 0; exp = TREE_CHAIN (exp))
329 if (calls_function_1 (TREE_VALUE (exp), which))
337 /* Only expressions, references, and blocks can contain calls. */
338 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
341 for (i = 0; i < length; i++)
342 if (TREE_OPERAND (exp, i) != 0
343 && calls_function_1 (TREE_OPERAND (exp, i), which))
349 /* Force FUNEXP into a form suitable for the address of a CALL,
350 and return that as an rtx. Also load the static chain register
351 if FNDECL is a nested function.
353 CALL_FUSAGE points to a variable holding the prospective
354 CALL_INSN_FUNCTION_USAGE information. */
357 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen)
363 rtx static_chain_value = 0;
365 funexp = protect_from_queue (funexp, 0);
368 /* Get possible static chain value for nested function in C. */
369 static_chain_value = lookup_static_chain (fndecl);
371 /* Make a valid memory address and copy constants thru pseudo-regs,
372 but not for a constant address if -fno-function-cse. */
373 if (GET_CODE (funexp) != SYMBOL_REF)
374 /* If we are using registers for parameters, force the
375 function address into a register now. */
376 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
377 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
378 : memory_address (FUNCTION_MODE, funexp));
381 #ifndef NO_FUNCTION_CSE
382 if (optimize && ! flag_no_function_cse)
383 #ifdef NO_RECURSIVE_FUNCTION_CSE
384 if (fndecl != current_function_decl)
386 funexp = force_reg (Pmode, funexp);
390 if (static_chain_value != 0)
392 emit_move_insn (static_chain_rtx, static_chain_value);
394 if (GET_CODE (static_chain_rtx) == REG)
395 use_reg (call_fusage, static_chain_rtx);
401 /* Generate instructions to call function FUNEXP,
402 and optionally pop the results.
403 The CALL_INSN is the first insn generated.
405 FNDECL is the declaration node of the function. This is given to the
406 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
408 FUNTYPE is the data type of the function. This is given to the macro
409 RETURN_POPS_ARGS to determine whether this function pops its own args.
410 We used to allow an identifier for library functions, but that doesn't
411 work when the return type is an aggregate type and the calling convention
412 says that the pointer to this aggregate is to be popped by the callee.
414 STACK_SIZE is the number of bytes of arguments on the stack,
415 ROUNDED_STACK_SIZE is that number rounded up to
416 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
417 both to put into the call insn and to generate explicit popping
420 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
421 It is zero if this call doesn't want a structure value.
423 NEXT_ARG_REG is the rtx that results from executing
424 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
425 just after all the args have had their registers assigned.
426 This could be whatever you like, but normally it is the first
427 arg-register beyond those used for args in this call,
428 or 0 if all the arg-registers are used in this call.
429 It is passed on to `gen_call' so you can put this info in the call insn.
431 VALREG is a hard register in which a value is returned,
432 or 0 if the call does not return a value.
434 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
435 the args to this call were processed.
436 We restore `inhibit_defer_pop' to that value.
438 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
439 denote registers used by the called function. */
442 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
443 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
444 call_fusage, ecf_flags)
446 tree fndecl ATTRIBUTE_UNUSED;
447 tree funtype ATTRIBUTE_UNUSED;
448 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
449 HOST_WIDE_INT rounded_stack_size;
450 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
453 int old_inhibit_defer_pop;
457 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
459 int already_popped = 0;
460 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
461 #if defined (HAVE_call) && defined (HAVE_call_value)
462 rtx struct_value_size_rtx;
463 struct_value_size_rtx = GEN_INT (struct_value_size);
466 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
467 and we don't want to load it into a register as an optimization,
468 because prepare_call_address already did it if it should be done. */
469 if (GET_CODE (funexp) != SYMBOL_REF)
470 funexp = memory_address (FUNCTION_MODE, funexp);
472 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
473 if ((ecf_flags & ECF_SIBCALL)
474 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
475 && (RETURN_POPS_ARGS (fndecl, funtype, stack_size) > 0
478 rtx n_pop = GEN_INT (RETURN_POPS_ARGS (fndecl, funtype, stack_size));
481 /* If this subroutine pops its own args, record that in the call insn
482 if possible, for the sake of frame pointer elimination. */
485 pat = GEN_SIBCALL_VALUE_POP (valreg,
486 gen_rtx_MEM (FUNCTION_MODE, funexp),
487 rounded_stack_size_rtx, next_arg_reg,
490 pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
491 rounded_stack_size_rtx, next_arg_reg, n_pop);
493 emit_call_insn (pat);
499 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
500 /* If the target has "call" or "call_value" insns, then prefer them
501 if no arguments are actually popped. If the target does not have
502 "call" or "call_value" insns, then we must use the popping versions
503 even if the call has no arguments to pop. */
504 #if defined (HAVE_call) && defined (HAVE_call_value)
505 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
506 && n_popped > 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
508 if (HAVE_call_pop && HAVE_call_value_pop)
511 rtx n_pop = GEN_INT (n_popped);
514 /* If this subroutine pops its own args, record that in the call insn
515 if possible, for the sake of frame pointer elimination. */
518 pat = GEN_CALL_VALUE_POP (valreg,
519 gen_rtx_MEM (FUNCTION_MODE, funexp),
520 rounded_stack_size_rtx, next_arg_reg, n_pop);
522 pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
523 rounded_stack_size_rtx, next_arg_reg, n_pop);
525 emit_call_insn (pat);
531 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
532 if ((ecf_flags & ECF_SIBCALL)
533 && HAVE_sibcall && HAVE_sibcall_value)
536 emit_call_insn (GEN_SIBCALL_VALUE (valreg,
537 gen_rtx_MEM (FUNCTION_MODE, funexp),
538 rounded_stack_size_rtx,
539 next_arg_reg, NULL_RTX));
541 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
542 rounded_stack_size_rtx, next_arg_reg,
543 struct_value_size_rtx));
548 #if defined (HAVE_call) && defined (HAVE_call_value)
549 if (HAVE_call && HAVE_call_value)
552 emit_call_insn (GEN_CALL_VALUE (valreg,
553 gen_rtx_MEM (FUNCTION_MODE, funexp),
554 rounded_stack_size_rtx, next_arg_reg,
557 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
558 rounded_stack_size_rtx, next_arg_reg,
559 struct_value_size_rtx));
565 /* Find the CALL insn we just emitted. */
566 for (call_insn = get_last_insn ();
567 call_insn && GET_CODE (call_insn) != CALL_INSN;
568 call_insn = PREV_INSN (call_insn))
574 /* Mark memory as used for "pure" function call. */
575 if (ecf_flags & ECF_PURE)
577 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
578 gen_rtx_USE (VOIDmode,
579 gen_rtx_MEM (BLKmode,
580 gen_rtx_SCRATCH (VOIDmode))), call_fusage);
583 /* Put the register usage information on the CALL. If there is already
584 some usage information, put ours at the end. */
585 if (CALL_INSN_FUNCTION_USAGE (call_insn))
589 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
590 link = XEXP (link, 1))
593 XEXP (link, 1) = call_fusage;
596 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
598 /* If this is a const call, then set the insn's unchanging bit. */
599 if (ecf_flags & (ECF_CONST | ECF_PURE))
600 CONST_CALL_P (call_insn) = 1;
602 /* If this call can't throw, attach a REG_EH_REGION reg note to that
604 if (ecf_flags & ECF_NOTHROW)
605 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
606 REG_NOTES (call_insn));
608 if (ecf_flags & ECF_NORETURN)
609 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_NORETURN, const0_rtx,
610 REG_NOTES (call_insn));
612 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
614 /* Restore this now, so that we do defer pops for this call's args
615 if the context of the call as a whole permits. */
616 inhibit_defer_pop = old_inhibit_defer_pop;
621 CALL_INSN_FUNCTION_USAGE (call_insn)
622 = gen_rtx_EXPR_LIST (VOIDmode,
623 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
624 CALL_INSN_FUNCTION_USAGE (call_insn));
625 rounded_stack_size -= n_popped;
626 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
627 stack_pointer_delta -= n_popped;
630 if (!ACCUMULATE_OUTGOING_ARGS)
632 /* If returning from the subroutine does not automatically pop the args,
633 we need an instruction to pop them sooner or later.
634 Perhaps do it now; perhaps just record how much space to pop later.
636 If returning from the subroutine does pop the args, indicate that the
637 stack pointer will be changed. */
639 if (rounded_stack_size != 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
641 if (flag_defer_pop && inhibit_defer_pop == 0
642 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
643 pending_stack_adjust += rounded_stack_size;
645 adjust_stack (rounded_stack_size_rtx);
648 /* When we accumulate outgoing args, we must avoid any stack manipulations.
649 Restore the stack pointer to its original value now. Usually
650 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
651 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
652 popping variants of functions exist as well.
654 ??? We may optimize similar to defer_pop above, but it is
655 probably not worthwhile.
657 ??? It will be worthwhile to enable combine_stack_adjustments even for
660 anti_adjust_stack (GEN_INT (n_popped));
663 /* Determine if the function identified by NAME and FNDECL is one with
664 special properties we wish to know about.
666 For example, if the function might return more than one time (setjmp), then
667 set RETURNS_TWICE to a nonzero value.
669 Similarly set LONGJMP for if the function is in the longjmp family.
671 Set MALLOC for any of the standard memory allocation functions which
672 allocate from the heap.
674 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
675 space from the stack such as alloca. */
678 special_function_p (fndecl, flags)
682 if (! (flags & ECF_MALLOC)
683 && fndecl && DECL_NAME (fndecl)
684 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
685 /* Exclude functions not at the file scope, or not `extern',
686 since they are not the magic functions we would otherwise
688 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
690 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
691 const char *tname = name;
693 /* We assume that alloca will always be called by name. It
694 makes no sense to pass it as a pointer-to-function to
695 anything that does not understand its behavior. */
696 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
698 && ! strcmp (name, "alloca"))
699 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
701 && ! strcmp (name, "__builtin_alloca"))))
702 flags |= ECF_MAY_BE_ALLOCA;
704 /* Disregard prefix _, __ or __x. */
707 if (name[1] == '_' && name[2] == 'x')
709 else if (name[1] == '_')
718 && (! strcmp (tname, "setjmp")
719 || ! strcmp (tname, "setjmp_syscall")))
721 && ! strcmp (tname, "sigsetjmp"))
723 && ! strcmp (tname, "savectx")))
724 flags |= ECF_RETURNS_TWICE;
727 && ! strcmp (tname, "siglongjmp"))
728 flags |= ECF_LONGJMP;
730 else if ((tname[0] == 'q' && tname[1] == 's'
731 && ! strcmp (tname, "qsetjmp"))
732 || (tname[0] == 'v' && tname[1] == 'f'
733 && ! strcmp (tname, "vfork")))
734 flags |= ECF_RETURNS_TWICE;
736 else if (tname[0] == 'l' && tname[1] == 'o'
737 && ! strcmp (tname, "longjmp"))
738 flags |= ECF_LONGJMP;
740 else if ((tname[0] == 'f' && tname[1] == 'o'
741 && ! strcmp (tname, "fork"))
742 /* Linux specific: __clone. check NAME to insist on the
743 leading underscores, to avoid polluting the ISO / POSIX
745 || (name[0] == '_' && name[1] == '_'
746 && ! strcmp (tname, "clone"))
747 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
748 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
750 || ((tname[5] == 'p' || tname[5] == 'e')
751 && tname[6] == '\0'))))
752 flags |= ECF_FORK_OR_EXEC;
754 /* Do not add any more malloc-like functions to this list,
755 instead mark them as malloc functions using the malloc attribute.
756 Note, realloc is not suitable for attribute malloc since
757 it may return the same address across multiple calls.
758 C++ operator new is not suitable because it is not required
759 to return a unique pointer; indeed, the standard placement new
760 just returns its argument. */
761 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl))) == Pmode
762 && (! strcmp (tname, "malloc")
763 || ! strcmp (tname, "calloc")
764 || ! strcmp (tname, "strdup")))
770 /* Return nonzero when tree represent call to longjmp. */
773 setjmp_call_p (fndecl)
776 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
779 /* Detect flags (function attributes) from the function type node. */
782 flags_from_decl_or_type (exp)
787 /* ??? We can't set IS_MALLOC for function types? */
790 /* The function exp may have the `malloc' attribute. */
791 if (DECL_P (exp) && DECL_IS_MALLOC (exp))
794 /* The function exp may have the `pure' attribute. */
795 if (DECL_P (exp) && DECL_IS_PURE (exp))
798 if (TREE_NOTHROW (exp))
799 flags |= ECF_NOTHROW;
802 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
805 if (TREE_THIS_VOLATILE (exp))
806 flags |= ECF_NORETURN;
811 /* Precompute all register parameters as described by ARGS, storing values
812 into fields within the ARGS array.
814 NUM_ACTUALS indicates the total number elements in the ARGS array.
816 Set REG_PARM_SEEN if we encounter a register parameter. */
819 precompute_register_parameters (num_actuals, args, reg_parm_seen)
821 struct arg_data *args;
828 for (i = 0; i < num_actuals; i++)
829 if (args[i].reg != 0 && ! args[i].pass_on_stack)
833 if (args[i].value == 0)
836 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
838 preserve_temp_slots (args[i].value);
841 /* ANSI doesn't require a sequence point here,
842 but PCC has one, so this will avoid some problems. */
846 /* If we are to promote the function arg to a wider mode,
849 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
851 = convert_modes (args[i].mode,
852 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
853 args[i].value, args[i].unsignedp);
855 /* If the value is expensive, and we are inside an appropriately
856 short loop, put the value into a pseudo and then put the pseudo
859 For small register classes, also do this if this call uses
860 register parameters. This is to avoid reload conflicts while
861 loading the parameters registers. */
863 if ((! (GET_CODE (args[i].value) == REG
864 || (GET_CODE (args[i].value) == SUBREG
865 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
866 && args[i].mode != BLKmode
867 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
868 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
869 || preserve_subexpressions_p ()))
870 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
874 #ifdef REG_PARM_STACK_SPACE
876 /* The argument list is the property of the called routine and it
877 may clobber it. If the fixed area has been used for previous
878 parameters, we must save and restore it. */
881 save_fixed_argument_area (reg_parm_stack_space, argblock,
882 low_to_save, high_to_save)
883 int reg_parm_stack_space;
889 rtx save_area = NULL_RTX;
891 /* Compute the boundary of the that needs to be saved, if any. */
892 #ifdef ARGS_GROW_DOWNWARD
893 for (i = 0; i < reg_parm_stack_space + 1; i++)
895 for (i = 0; i < reg_parm_stack_space; i++)
898 if (i >= highest_outgoing_arg_in_use
899 || stack_usage_map[i] == 0)
902 if (*low_to_save == -1)
908 if (*low_to_save >= 0)
910 int num_to_save = *high_to_save - *low_to_save + 1;
911 enum machine_mode save_mode
912 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
915 /* If we don't have the required alignment, must do this in BLKmode. */
916 if ((*low_to_save & (MIN (GET_MODE_SIZE (save_mode),
917 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
920 #ifdef ARGS_GROW_DOWNWARD
922 = gen_rtx_MEM (save_mode,
923 memory_address (save_mode,
924 plus_constant (argblock,
927 stack_area = gen_rtx_MEM (save_mode,
928 memory_address (save_mode,
929 plus_constant (argblock,
932 if (save_mode == BLKmode)
934 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
935 /* Cannot use emit_block_move here because it can be done by a
936 library call which in turn gets into this place again and deadly
937 infinite recursion happens. */
938 move_by_pieces (validize_mem (save_area), stack_area, num_to_save,
943 save_area = gen_reg_rtx (save_mode);
944 emit_move_insn (save_area, stack_area);
951 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
957 enum machine_mode save_mode = GET_MODE (save_area);
958 #ifdef ARGS_GROW_DOWNWARD
960 = gen_rtx_MEM (save_mode,
961 memory_address (save_mode,
962 plus_constant (argblock,
966 = gen_rtx_MEM (save_mode,
967 memory_address (save_mode,
968 plus_constant (argblock,
972 if (save_mode != BLKmode)
973 emit_move_insn (stack_area, save_area);
975 /* Cannot use emit_block_move here because it can be done by a library
976 call which in turn gets into this place again and deadly infinite
977 recursion happens. */
978 move_by_pieces (stack_area, validize_mem (save_area),
979 high_to_save - low_to_save + 1, PARM_BOUNDARY);
983 /* If any elements in ARGS refer to parameters that are to be passed in
984 registers, but not in memory, and whose alignment does not permit a
985 direct copy into registers. Copy the values into a group of pseudos
986 which we will later copy into the appropriate hard registers.
988 Pseudos for each unaligned argument will be stored into the array
989 args[argnum].aligned_regs. The caller is responsible for deallocating
990 the aligned_regs array if it is nonzero. */
993 store_unaligned_arguments_into_pseudos (args, num_actuals)
994 struct arg_data *args;
999 for (i = 0; i < num_actuals; i++)
1000 if (args[i].reg != 0 && ! args[i].pass_on_stack
1001 && args[i].mode == BLKmode
1002 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1003 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1005 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1006 int big_endian_correction = 0;
1008 args[i].n_aligned_regs
1009 = args[i].partial ? args[i].partial
1010 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1012 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
1013 * args[i].n_aligned_regs);
1015 /* Structures smaller than a word are aligned to the least
1016 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1017 this means we must skip the empty high order bytes when
1018 calculating the bit offset. */
1019 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
1020 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1022 for (j = 0; j < args[i].n_aligned_regs; j++)
1024 rtx reg = gen_reg_rtx (word_mode);
1025 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1026 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1027 int bitalign = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
1029 args[i].aligned_regs[j] = reg;
1031 /* There is no need to restrict this code to loading items
1032 in TYPE_ALIGN sized hunks. The bitfield instructions can
1033 load up entire word sized registers efficiently.
1035 ??? This may not be needed anymore.
1036 We use to emit a clobber here but that doesn't let later
1037 passes optimize the instructions we emit. By storing 0 into
1038 the register later passes know the first AND to zero out the
1039 bitfield being set in the register is unnecessary. The store
1040 of 0 will be deleted as will at least the first AND. */
1042 emit_move_insn (reg, const0_rtx);
1044 bytes -= bitsize / BITS_PER_UNIT;
1045 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
1046 extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1047 word_mode, word_mode, bitalign,
1049 bitalign, BITS_PER_WORD);
1054 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1057 NUM_ACTUALS is the total number of parameters.
1059 N_NAMED_ARGS is the total number of named arguments.
1061 FNDECL is the tree code for the target of this call (if known)
1063 ARGS_SO_FAR holds state needed by the target to know where to place
1066 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1067 for arguments which are passed in registers.
1069 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1070 and may be modified by this routine.
1072 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1073 flags which may may be modified by this routine. */
1076 initialize_argument_information (num_actuals, args, args_size, n_named_args,
1077 actparms, fndecl, args_so_far,
1078 reg_parm_stack_space, old_stack_level,
1079 old_pending_adj, must_preallocate,
1081 int num_actuals ATTRIBUTE_UNUSED;
1082 struct arg_data *args;
1083 struct args_size *args_size;
1084 int n_named_args ATTRIBUTE_UNUSED;
1087 CUMULATIVE_ARGS *args_so_far;
1088 int reg_parm_stack_space;
1089 rtx *old_stack_level;
1090 int *old_pending_adj;
1091 int *must_preallocate;
1094 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1097 /* Count arg position in order args appear. */
1100 struct args_size alignment_pad;
1104 args_size->constant = 0;
1107 /* In this loop, we consider args in the order they are written.
1108 We fill up ARGS from the front or from the back if necessary
1109 so that in any case the first arg to be pushed ends up at the front. */
1111 if (PUSH_ARGS_REVERSED)
1113 i = num_actuals - 1, inc = -1;
1114 /* In this case, must reverse order of args
1115 so that we compute and push the last arg first. */
1122 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1123 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1125 tree type = TREE_TYPE (TREE_VALUE (p));
1127 enum machine_mode mode;
1129 args[i].tree_value = TREE_VALUE (p);
1131 /* Replace erroneous argument with constant zero. */
1132 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1133 args[i].tree_value = integer_zero_node, type = integer_type_node;
1135 /* If TYPE is a transparent union, pass things the way we would
1136 pass the first field of the union. We have already verified that
1137 the modes are the same. */
1138 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1139 type = TREE_TYPE (TYPE_FIELDS (type));
1141 /* Decide where to pass this arg.
1143 args[i].reg is nonzero if all or part is passed in registers.
1145 args[i].partial is nonzero if part but not all is passed in registers,
1146 and the exact value says how many words are passed in registers.
1148 args[i].pass_on_stack is nonzero if the argument must at least be
1149 computed on the stack. It may then be loaded back into registers
1150 if args[i].reg is nonzero.
1152 These decisions are driven by the FUNCTION_... macros and must agree
1153 with those made by function.c. */
1155 /* See if this argument should be passed by invisible reference. */
1156 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1157 && contains_placeholder_p (TYPE_SIZE (type)))
1158 || TREE_ADDRESSABLE (type)
1159 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1160 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1161 type, argpos < n_named_args)
1165 /* If we're compiling a thunk, pass through invisible
1166 references instead of making a copy. */
1167 if (current_function_is_thunk
1168 #ifdef FUNCTION_ARG_CALLEE_COPIES
1169 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1170 type, argpos < n_named_args)
1171 /* If it's in a register, we must make a copy of it too. */
1172 /* ??? Is this a sufficient test? Is there a better one? */
1173 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1174 && REG_P (DECL_RTL (args[i].tree_value)))
1175 && ! TREE_ADDRESSABLE (type))
1179 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1180 new object from the argument. If we are passing by
1181 invisible reference, the callee will do that for us, so we
1182 can strip off the TARGET_EXPR. This is not always safe,
1183 but it is safe in the only case where this is a useful
1184 optimization; namely, when the argument is a plain object.
1185 In that case, the frontend is just asking the backend to
1186 make a bitwise copy of the argument. */
1188 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1189 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1190 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1191 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1193 args[i].tree_value = build1 (ADDR_EXPR,
1194 build_pointer_type (type),
1195 args[i].tree_value);
1196 type = build_pointer_type (type);
1200 /* We make a copy of the object and pass the address to the
1201 function being called. */
1204 if (!COMPLETE_TYPE_P (type)
1205 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1206 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1207 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1208 STACK_CHECK_MAX_VAR_SIZE))))
1210 /* This is a variable-sized object. Make space on the stack
1212 rtx size_rtx = expr_size (TREE_VALUE (p));
1214 if (*old_stack_level == 0)
1216 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1217 *old_pending_adj = pending_stack_adjust;
1218 pending_stack_adjust = 0;
1221 copy = gen_rtx_MEM (BLKmode,
1222 allocate_dynamic_stack_space
1223 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1224 set_mem_attributes (copy, type, 1);
1227 copy = assign_temp (type, 0, 1, 0);
1229 store_expr (args[i].tree_value, copy, 0);
1230 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1232 args[i].tree_value = build1 (ADDR_EXPR,
1233 build_pointer_type (type),
1234 make_tree (type, copy));
1235 type = build_pointer_type (type);
1239 mode = TYPE_MODE (type);
1240 unsignedp = TREE_UNSIGNED (type);
1242 #ifdef PROMOTE_FUNCTION_ARGS
1243 mode = promote_mode (type, mode, &unsignedp, 1);
1246 args[i].unsignedp = unsignedp;
1247 args[i].mode = mode;
1249 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1250 argpos < n_named_args);
1251 #ifdef FUNCTION_INCOMING_ARG
1252 /* If this is a sibling call and the machine has register windows, the
1253 register window has to be unwinded before calling the routine, so
1254 arguments have to go into the incoming registers. */
1255 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1256 argpos < n_named_args);
1258 args[i].tail_call_reg = args[i].reg;
1261 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1264 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1265 argpos < n_named_args);
1268 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1270 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1271 it means that we are to pass this arg in the register(s) designated
1272 by the PARALLEL, but also to pass it in the stack. */
1273 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1274 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1275 args[i].pass_on_stack = 1;
1277 /* If this is an addressable type, we must preallocate the stack
1278 since we must evaluate the object into its final location.
1280 If this is to be passed in both registers and the stack, it is simpler
1282 if (TREE_ADDRESSABLE (type)
1283 || (args[i].pass_on_stack && args[i].reg != 0))
1284 *must_preallocate = 1;
1286 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1287 we cannot consider this function call constant. */
1288 if (TREE_ADDRESSABLE (type))
1289 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1291 /* Compute the stack-size of this argument. */
1292 if (args[i].reg == 0 || args[i].partial != 0
1293 || reg_parm_stack_space > 0
1294 || args[i].pass_on_stack)
1295 locate_and_pad_parm (mode, type,
1296 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1301 fndecl, args_size, &args[i].offset,
1302 &args[i].size, &alignment_pad);
1304 #ifndef ARGS_GROW_DOWNWARD
1305 args[i].slot_offset = *args_size;
1308 args[i].alignment_pad = alignment_pad;
1310 /* If a part of the arg was put into registers,
1311 don't include that part in the amount pushed. */
1312 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1313 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1314 / (PARM_BOUNDARY / BITS_PER_UNIT)
1315 * (PARM_BOUNDARY / BITS_PER_UNIT));
1317 /* Update ARGS_SIZE, the total stack space for args so far. */
1319 args_size->constant += args[i].size.constant;
1320 if (args[i].size.var)
1322 ADD_PARM_SIZE (*args_size, args[i].size.var);
1325 /* Since the slot offset points to the bottom of the slot,
1326 we must record it after incrementing if the args grow down. */
1327 #ifdef ARGS_GROW_DOWNWARD
1328 args[i].slot_offset = *args_size;
1330 args[i].slot_offset.constant = -args_size->constant;
1332 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1335 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1336 have been used, etc. */
1338 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1339 argpos < n_named_args);
1343 /* Update ARGS_SIZE to contain the total size for the argument block.
1344 Return the original constant component of the argument block's size.
1346 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1347 for arguments passed in registers. */
1350 compute_argument_block_size (reg_parm_stack_space, args_size,
1351 preferred_stack_boundary)
1352 int reg_parm_stack_space;
1353 struct args_size *args_size;
1354 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1356 int unadjusted_args_size = args_size->constant;
1358 /* For accumulate outgoing args mode we don't need to align, since the frame
1359 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1360 backends from generating missaligned frame sizes. */
1361 #ifdef STACK_BOUNDARY
1362 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1363 preferred_stack_boundary = STACK_BOUNDARY;
1366 /* Compute the actual size of the argument block required. The variable
1367 and constant sizes must be combined, the size may have to be rounded,
1368 and there may be a minimum required size. */
1372 args_size->var = ARGS_SIZE_TREE (*args_size);
1373 args_size->constant = 0;
1375 #ifdef PREFERRED_STACK_BOUNDARY
1376 preferred_stack_boundary /= BITS_PER_UNIT;
1377 if (preferred_stack_boundary > 1)
1379 /* We don't handle this case yet. To handle it correctly we have
1380 to add the delta, round and substract the delta.
1381 Currently no machine description requires this support. */
1382 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1384 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1388 if (reg_parm_stack_space > 0)
1391 = size_binop (MAX_EXPR, args_size->var,
1392 ssize_int (reg_parm_stack_space));
1394 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1395 /* The area corresponding to register parameters is not to count in
1396 the size of the block we need. So make the adjustment. */
1398 = size_binop (MINUS_EXPR, args_size->var,
1399 ssize_int (reg_parm_stack_space));
1405 #ifdef PREFERRED_STACK_BOUNDARY
1406 preferred_stack_boundary /= BITS_PER_UNIT;
1407 if (preferred_stack_boundary < 1)
1408 preferred_stack_boundary = 1;
1409 args_size->constant = (((args_size->constant
1410 + stack_pointer_delta
1411 + preferred_stack_boundary - 1)
1412 / preferred_stack_boundary
1413 * preferred_stack_boundary)
1414 - stack_pointer_delta);
1417 args_size->constant = MAX (args_size->constant,
1418 reg_parm_stack_space);
1420 #ifdef MAYBE_REG_PARM_STACK_SPACE
1421 if (reg_parm_stack_space == 0)
1422 args_size->constant = 0;
1425 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1426 args_size->constant -= reg_parm_stack_space;
1429 return unadjusted_args_size;
1432 /* Precompute parameters as needed for a function call.
1434 FLAGS is mask of ECF_* constants.
1436 NUM_ACTUALS is the number of arguments.
1438 ARGS is an array containing information for each argument; this
1439 routine fills in the INITIAL_VALUE and VALUE fields for each
1440 precomputed argument. */
1443 precompute_arguments (flags, num_actuals, args)
1446 struct arg_data *args;
1450 /* If this function call is cse'able, precompute all the parameters.
1451 Note that if the parameter is constructed into a temporary, this will
1452 cause an additional copy because the parameter will be constructed
1453 into a temporary location and then copied into the outgoing arguments.
1454 If a parameter contains a call to alloca and this function uses the
1455 stack, precompute the parameter. */
1457 /* If we preallocated the stack space, and some arguments must be passed
1458 on the stack, then we must precompute any parameter which contains a
1459 function call which will store arguments on the stack.
1460 Otherwise, evaluating the parameter may clobber previous parameters
1461 which have already been stored into the stack. (we have code to avoid
1462 such case by saving the ougoing stack arguments, but it results in
1465 for (i = 0; i < num_actuals; i++)
1466 if ((flags & (ECF_CONST | ECF_PURE))
1467 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1469 /* If this is an addressable type, we cannot pre-evaluate it. */
1470 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1476 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1478 preserve_temp_slots (args[i].value);
1481 /* ANSI doesn't require a sequence point here,
1482 but PCC has one, so this will avoid some problems. */
1485 args[i].initial_value = args[i].value
1486 = protect_from_queue (args[i].value, 0);
1488 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) != args[i].mode)
1491 = convert_modes (args[i].mode,
1492 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1493 args[i].value, args[i].unsignedp);
1494 #ifdef PROMOTE_FOR_CALL_ONLY
1495 /* CSE will replace this only if it contains args[i].value
1496 pseudo, so convert it down to the declared mode using
1498 if (GET_CODE (args[i].value) == REG
1499 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1501 args[i].initial_value
1502 = gen_rtx_SUBREG (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1504 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1505 SUBREG_PROMOTED_UNSIGNED_P (args[i].initial_value)
1506 = args[i].unsignedp;
1513 /* Given the current state of MUST_PREALLOCATE and information about
1514 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1515 compute and return the final value for MUST_PREALLOCATE. */
1518 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1519 int must_preallocate;
1521 struct arg_data *args;
1522 struct args_size *args_size;
1524 /* See if we have or want to preallocate stack space.
1526 If we would have to push a partially-in-regs parm
1527 before other stack parms, preallocate stack space instead.
1529 If the size of some parm is not a multiple of the required stack
1530 alignment, we must preallocate.
1532 If the total size of arguments that would otherwise create a copy in
1533 a temporary (such as a CALL) is more than half the total argument list
1534 size, preallocation is faster.
1536 Another reason to preallocate is if we have a machine (like the m88k)
1537 where stack alignment is required to be maintained between every
1538 pair of insns, not just when the call is made. However, we assume here
1539 that such machines either do not have push insns (and hence preallocation
1540 would occur anyway) or the problem is taken care of with
1543 if (! must_preallocate)
1545 int partial_seen = 0;
1546 int copy_to_evaluate_size = 0;
1549 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1551 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1553 else if (partial_seen && args[i].reg == 0)
1554 must_preallocate = 1;
1556 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1557 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1558 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1559 || TREE_CODE (args[i].tree_value) == COND_EXPR
1560 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1561 copy_to_evaluate_size
1562 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1565 if (copy_to_evaluate_size * 2 >= args_size->constant
1566 && args_size->constant > 0)
1567 must_preallocate = 1;
1569 return must_preallocate;
1572 /* If we preallocated stack space, compute the address of each argument
1573 and store it into the ARGS array.
1575 We need not ensure it is a valid memory address here; it will be
1576 validized when it is used.
1578 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1581 compute_argument_addresses (args, argblock, num_actuals)
1582 struct arg_data *args;
1588 rtx arg_reg = argblock;
1589 int i, arg_offset = 0;
1591 if (GET_CODE (argblock) == PLUS)
1592 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1594 for (i = 0; i < num_actuals; i++)
1596 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1597 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1600 /* Skip this parm if it will not be passed on the stack. */
1601 if (! args[i].pass_on_stack && args[i].reg != 0)
1604 if (GET_CODE (offset) == CONST_INT)
1605 addr = plus_constant (arg_reg, INTVAL (offset));
1607 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1609 addr = plus_constant (addr, arg_offset);
1610 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1611 set_mem_attributes (args[i].stack,
1612 TREE_TYPE (args[i].tree_value), 1);
1614 if (GET_CODE (slot_offset) == CONST_INT)
1615 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1617 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1619 addr = plus_constant (addr, arg_offset);
1620 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1621 set_mem_attributes (args[i].stack_slot,
1622 TREE_TYPE (args[i].tree_value), 1);
1624 /* Function incoming arguments may overlap with sibling call
1625 outgoing arguments and we cannot allow reordering of reads
1626 from function arguments with stores to outgoing arguments
1627 of sibling calls. */
1628 MEM_ALIAS_SET (args[i].stack) = 0;
1629 MEM_ALIAS_SET (args[i].stack_slot) = 0;
1634 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1635 in a call instruction.
1637 FNDECL is the tree node for the target function. For an indirect call
1638 FNDECL will be NULL_TREE.
1640 EXP is the CALL_EXPR for this call. */
1643 rtx_for_function_call (fndecl, exp)
1649 /* Get the function to call, in the form of RTL. */
1652 /* If this is the first use of the function, see if we need to
1653 make an external definition for it. */
1654 if (! TREE_USED (fndecl))
1656 assemble_external (fndecl);
1657 TREE_USED (fndecl) = 1;
1660 /* Get a SYMBOL_REF rtx for the function address. */
1661 funexp = XEXP (DECL_RTL (fndecl), 0);
1664 /* Generate an rtx (probably a pseudo-register) for the address. */
1669 expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1670 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1672 /* Check the function is executable. */
1673 if (current_function_check_memory_usage)
1675 #ifdef POINTERS_EXTEND_UNSIGNED
1676 /* It might be OK to convert funexp in place, but there's
1677 a lot going on between here and when it happens naturally
1678 that this seems safer. */
1679 funaddr = convert_memory_address (Pmode, funexp);
1681 emit_library_call (chkr_check_exec_libfunc, 1,
1690 /* Do the register loads required for any wholly-register parms or any
1691 parms which are passed both on the stack and in a register. Their
1692 expressions were already evaluated.
1694 Mark all register-parms as living through the call, putting these USE
1695 insns in the CALL_INSN_FUNCTION_USAGE field. */
1698 load_register_parameters (args, num_actuals, call_fusage, flags)
1699 struct arg_data *args;
1706 #ifdef LOAD_ARGS_REVERSED
1707 for (i = num_actuals - 1; i >= 0; i--)
1709 for (i = 0; i < num_actuals; i++)
1712 rtx reg = ((flags & ECF_SIBCALL)
1713 ? args[i].tail_call_reg : args[i].reg);
1714 int partial = args[i].partial;
1719 /* Set to non-negative if must move a word at a time, even if just
1720 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1721 we just use a normal move insn. This value can be zero if the
1722 argument is a zero size structure with no fields. */
1723 nregs = (partial ? partial
1724 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1725 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1726 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1729 /* Handle calls that pass values in multiple non-contiguous
1730 locations. The Irix 6 ABI has examples of this. */
1732 if (GET_CODE (reg) == PARALLEL)
1733 emit_group_load (reg, args[i].value,
1734 int_size_in_bytes (TREE_TYPE (args[i].tree_value)),
1735 TYPE_ALIGN (TREE_TYPE (args[i].tree_value)));
1737 /* If simple case, just do move. If normal partial, store_one_arg
1738 has already loaded the register for us. In all other cases,
1739 load the register(s) from memory. */
1741 else if (nregs == -1)
1742 emit_move_insn (reg, args[i].value);
1744 /* If we have pre-computed the values to put in the registers in
1745 the case of non-aligned structures, copy them in now. */
1747 else if (args[i].n_aligned_regs != 0)
1748 for (j = 0; j < args[i].n_aligned_regs; j++)
1749 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1750 args[i].aligned_regs[j]);
1752 else if (partial == 0 || args[i].pass_on_stack)
1753 move_block_to_reg (REGNO (reg),
1754 validize_mem (args[i].value), nregs,
1757 /* Handle calls that pass values in multiple non-contiguous
1758 locations. The Irix 6 ABI has examples of this. */
1759 if (GET_CODE (reg) == PARALLEL)
1760 use_group_regs (call_fusage, reg);
1761 else if (nregs == -1)
1762 use_reg (call_fusage, reg);
1764 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1769 /* Try to integrate function. See expand_inline_function for documentation
1770 about the parameters. */
1773 try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1779 rtx structure_value_addr;
1784 rtx old_stack_level = 0;
1785 int reg_parm_stack_space = 0;
1787 #ifdef REG_PARM_STACK_SPACE
1788 #ifdef MAYBE_REG_PARM_STACK_SPACE
1789 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1791 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1795 before_call = get_last_insn ();
1797 timevar_push (TV_INTEGRATION);
1799 temp = expand_inline_function (fndecl, actparms, target,
1801 structure_value_addr);
1803 timevar_pop (TV_INTEGRATION);
1805 /* If inlining succeeded, return. */
1806 if (temp != (rtx) (HOST_WIDE_INT) - 1)
1808 if (ACCUMULATE_OUTGOING_ARGS)
1810 /* If the outgoing argument list must be preserved, push
1811 the stack before executing the inlined function if it
1814 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1815 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1818 if (stack_arg_under_construction || i >= 0)
1821 = before_call ? NEXT_INSN (before_call) : get_insns ();
1822 rtx insn = NULL_RTX, seq;
1824 /* Look for a call in the inline function code.
1825 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1826 nonzero then there is a call and it is not necessary
1827 to scan the insns. */
1829 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1830 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1831 if (GET_CODE (insn) == CALL_INSN)
1836 /* Reserve enough stack space so that the largest
1837 argument list of any function call in the inline
1838 function does not overlap the argument list being
1839 evaluated. This is usually an overestimate because
1840 allocate_dynamic_stack_space reserves space for an
1841 outgoing argument list in addition to the requested
1842 space, but there is no way to ask for stack space such
1843 that an argument list of a certain length can be
1846 Add the stack space reserved for register arguments, if
1847 any, in the inline function. What is really needed is the
1848 largest value of reg_parm_stack_space in the inline
1849 function, but that is not available. Using the current
1850 value of reg_parm_stack_space is wrong, but gives
1851 correct results on all supported machines. */
1853 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1854 + reg_parm_stack_space);
1857 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1858 allocate_dynamic_stack_space (GEN_INT (adjust),
1859 NULL_RTX, BITS_PER_UNIT);
1862 emit_insns_before (seq, first_insn);
1863 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1868 /* If the result is equivalent to TARGET, return TARGET to simplify
1869 checks in store_expr. They can be equivalent but not equal in the
1870 case of a function that returns BLKmode. */
1871 if (temp != target && rtx_equal_p (temp, target))
1876 /* If inlining failed, mark FNDECL as needing to be compiled
1877 separately after all. If function was declared inline,
1879 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1880 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1882 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1883 warning ("called from here");
1885 mark_addressable (fndecl);
1886 return (rtx) (HOST_WIDE_INT) - 1;
1889 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1890 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1891 bytes, then we would need to push some additional bytes to pad the
1892 arguments. So, we compute an adjust to the stack pointer for an
1893 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1894 bytes. Then, when the arguments are pushed the stack will be perfectly
1895 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1896 be popped after the call. Returns the adjustment. */
1899 combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1901 preferred_unit_stack_boundary)
1902 int unadjusted_args_size;
1903 struct args_size *args_size;
1904 int preferred_unit_stack_boundary;
1906 /* The number of bytes to pop so that the stack will be
1907 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1908 HOST_WIDE_INT adjustment;
1909 /* The alignment of the stack after the arguments are pushed, if we
1910 just pushed the arguments without adjust the stack here. */
1911 HOST_WIDE_INT unadjusted_alignment;
1913 unadjusted_alignment
1914 = ((stack_pointer_delta + unadjusted_args_size)
1915 % preferred_unit_stack_boundary);
1917 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1918 as possible -- leaving just enough left to cancel out the
1919 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1920 PENDING_STACK_ADJUST is non-negative, and congruent to
1921 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1923 /* Begin by trying to pop all the bytes. */
1924 unadjusted_alignment
1925 = (unadjusted_alignment
1926 - (pending_stack_adjust % preferred_unit_stack_boundary));
1927 adjustment = pending_stack_adjust;
1928 /* Push enough additional bytes that the stack will be aligned
1929 after the arguments are pushed. */
1930 if (preferred_unit_stack_boundary > 1)
1932 if (unadjusted_alignment >= 0)
1933 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1935 adjustment += unadjusted_alignment;
1938 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1939 bytes after the call. The right number is the entire
1940 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1941 by the arguments in the first place. */
1943 = pending_stack_adjust - adjustment + unadjusted_args_size;
1948 /* Scan X expression if it does not dereference any argument slots
1949 we already clobbered by tail call arguments (as noted in stored_args_map
1951 Return non-zero if X expression dereferences such argument slots,
1955 check_sibcall_argument_overlap_1 (x)
1966 code = GET_CODE (x);
1970 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1972 else if (GET_CODE (XEXP (x, 0)) == PLUS
1973 && XEXP (XEXP (x, 0), 0) ==
1974 current_function_internal_arg_pointer
1975 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1976 i = INTVAL (XEXP (XEXP (x, 0), 1));
1980 #ifdef ARGS_GROW_DOWNWARD
1981 i = -i - GET_MODE_SIZE (GET_MODE (x));
1984 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
1985 if (i + k < stored_args_map->n_bits
1986 && TEST_BIT (stored_args_map, i + k))
1992 /* Scan all subexpressions. */
1993 fmt = GET_RTX_FORMAT (code);
1994 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1998 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2001 else if (*fmt == 'E')
2003 for (j = 0; j < XVECLEN (x, i); j++)
2004 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2011 /* Scan sequence after INSN if it does not dereference any argument slots
2012 we already clobbered by tail call arguments (as noted in stored_args_map
2013 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2014 Return non-zero if sequence after INSN dereferences such argument slots,
2018 check_sibcall_argument_overlap (insn, arg)
2020 struct arg_data *arg;
2024 if (insn == NULL_RTX)
2025 insn = get_insns ();
2027 insn = NEXT_INSN (insn);
2029 for (; insn; insn = NEXT_INSN (insn))
2031 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2034 #ifdef ARGS_GROW_DOWNWARD
2035 low = -arg->offset.constant - arg->size.constant;
2037 low = arg->offset.constant;
2040 for (high = low + arg->size.constant; low < high; low++)
2041 SET_BIT (stored_args_map, low);
2042 return insn != NULL_RTX;
2045 /* Generate all the code for a function call
2046 and return an rtx for its value.
2047 Store the value in TARGET (specified as an rtx) if convenient.
2048 If the value is stored in TARGET then TARGET is returned.
2049 If IGNORE is nonzero, then we ignore the value of the function call. */
2052 expand_call (exp, target, ignore)
2057 /* Nonzero if we are currently expanding a call. */
2058 static int currently_expanding_call = 0;
2060 /* List of actual parameters. */
2061 tree actparms = TREE_OPERAND (exp, 1);
2062 /* RTX for the function to be called. */
2064 /* Sequence of insns to perform a tail recursive "call". */
2065 rtx tail_recursion_insns = NULL_RTX;
2066 /* Sequence of insns to perform a normal "call". */
2067 rtx normal_call_insns = NULL_RTX;
2068 /* Sequence of insns to perform a tail recursive "call". */
2069 rtx tail_call_insns = NULL_RTX;
2070 /* Data type of the function. */
2072 /* Declaration of the function being called,
2073 or 0 if the function is computed (not known by name). */
2076 int try_tail_call = 1;
2077 int try_tail_recursion = 1;
2080 /* Register in which non-BLKmode value will be returned,
2081 or 0 if no value or if value is BLKmode. */
2083 /* Address where we should return a BLKmode value;
2084 0 if value not BLKmode. */
2085 rtx structure_value_addr = 0;
2086 /* Nonzero if that address is being passed by treating it as
2087 an extra, implicit first parameter. Otherwise,
2088 it is passed by being copied directly into struct_value_rtx. */
2089 int structure_value_addr_parm = 0;
2090 /* Size of aggregate value wanted, or zero if none wanted
2091 or if we are using the non-reentrant PCC calling convention
2092 or expecting the value in registers. */
2093 HOST_WIDE_INT struct_value_size = 0;
2094 /* Nonzero if called function returns an aggregate in memory PCC style,
2095 by returning the address of where to find it. */
2096 int pcc_struct_value = 0;
2098 /* Number of actual parameters in this call, including struct value addr. */
2100 /* Number of named args. Args after this are anonymous ones
2101 and they must all go on the stack. */
2104 /* Vector of information about each argument.
2105 Arguments are numbered in the order they will be pushed,
2106 not the order they are written. */
2107 struct arg_data *args;
2109 /* Total size in bytes of all the stack-parms scanned so far. */
2110 struct args_size args_size;
2111 struct args_size adjusted_args_size;
2112 /* Size of arguments before any adjustments (such as rounding). */
2113 int unadjusted_args_size;
2114 /* Data on reg parms scanned so far. */
2115 CUMULATIVE_ARGS args_so_far;
2116 /* Nonzero if a reg parm has been scanned. */
2118 /* Nonzero if this is an indirect function call. */
2120 /* Nonzero if we must avoid push-insns in the args for this call.
2121 If stack space is allocated for register parameters, but not by the
2122 caller, then it is preallocated in the fixed part of the stack frame.
2123 So the entire argument block must then be preallocated (i.e., we
2124 ignore PUSH_ROUNDING in that case). */
2126 int must_preallocate = !PUSH_ARGS;
2128 /* Size of the stack reserved for parameter registers. */
2129 int reg_parm_stack_space = 0;
2131 /* Address of space preallocated for stack parms
2132 (on machines that lack push insns), or 0 if space not preallocated. */
2135 /* Mask of ECF_ flags. */
2137 /* Nonzero if this is a call to an inline function. */
2138 int is_integrable = 0;
2139 #ifdef REG_PARM_STACK_SPACE
2140 /* Define the boundary of the register parm stack space that needs to be
2142 int low_to_save = -1, high_to_save;
2143 rtx save_area = 0; /* Place that it is saved */
2146 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2147 char *initial_stack_usage_map = stack_usage_map;
2148 int old_stack_arg_under_construction = 0;
2150 rtx old_stack_level = 0;
2151 int old_pending_adj = 0;
2152 int old_inhibit_defer_pop = inhibit_defer_pop;
2153 int old_stack_allocated;
2155 register tree p = TREE_OPERAND (exp, 0);
2157 /* The alignment of the stack, in bits. */
2158 HOST_WIDE_INT preferred_stack_boundary;
2159 /* The alignment of the stack, in bytes. */
2160 HOST_WIDE_INT preferred_unit_stack_boundary;
2162 /* The value of the function call can be put in a hard register. But
2163 if -fcheck-memory-usage, code which invokes functions (and thus
2164 damages some hard registers) can be inserted before using the value.
2165 So, target is always a pseudo-register in that case. */
2166 if (current_function_check_memory_usage)
2169 /* See if this is "nothrow" function call. */
2170 if (TREE_NOTHROW (exp))
2171 flags |= ECF_NOTHROW;
2173 /* See if we can find a DECL-node for the actual function.
2174 As a result, decide whether this is a call to an integrable function. */
2176 fndecl = get_callee_fndecl (exp);
2180 && fndecl != current_function_decl
2181 && DECL_INLINE (fndecl)
2182 && DECL_SAVED_INSNS (fndecl)
2183 && DECL_SAVED_INSNS (fndecl)->inlinable)
2185 else if (! TREE_ADDRESSABLE (fndecl))
2187 /* In case this function later becomes inlinable,
2188 record that there was already a non-inline call to it.
2190 Use abstraction instead of setting TREE_ADDRESSABLE
2192 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2195 warning_with_decl (fndecl, "can't inline call to `%s'");
2196 warning ("called from here");
2198 mark_addressable (fndecl);
2201 flags |= flags_from_decl_or_type (fndecl);
2204 /* If we don't have specific function to call, see if we have a
2205 attributes set in the type. */
2207 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2209 /* Mark if the function returns with the stack pointer depressed. */
2210 if (TREE_CODE (TREE_TYPE (TREE_TYPE (p))) == FUNCTION_TYPE
2211 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (TREE_TYPE (p))))
2213 flags |= ECF_SP_DEPRESSED;
2214 flags &= ~(ECF_PURE | ECF_CONST);
2217 #ifdef REG_PARM_STACK_SPACE
2218 #ifdef MAYBE_REG_PARM_STACK_SPACE
2219 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2221 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2225 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2226 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2227 must_preallocate = 1;
2230 /* Warn if this value is an aggregate type,
2231 regardless of which calling convention we are using for it. */
2232 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2233 warning ("function call has aggregate value");
2235 /* Set up a place to return a structure. */
2237 /* Cater to broken compilers. */
2238 if (aggregate_value_p (exp))
2240 /* This call returns a big structure. */
2241 flags &= ~(ECF_CONST | ECF_PURE);
2243 #ifdef PCC_STATIC_STRUCT_RETURN
2245 pcc_struct_value = 1;
2246 /* Easier than making that case work right. */
2249 /* In case this is a static function, note that it has been
2251 if (! TREE_ADDRESSABLE (fndecl))
2252 mark_addressable (fndecl);
2256 #else /* not PCC_STATIC_STRUCT_RETURN */
2258 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2260 if (target && GET_CODE (target) == MEM)
2261 structure_value_addr = XEXP (target, 0);
2266 /* For variable-sized objects, we must be called with a target
2267 specified. If we were to allocate space on the stack here,
2268 we would have no way of knowing when to free it. */
2270 if (struct_value_size < 0)
2273 d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2274 mark_temp_addr_taken (d);
2275 structure_value_addr = XEXP (d, 0);
2279 #endif /* not PCC_STATIC_STRUCT_RETURN */
2282 /* If called function is inline, try to integrate it. */
2286 rtx temp = try_to_integrate (fndecl, actparms, target,
2287 ignore, TREE_TYPE (exp),
2288 structure_value_addr);
2289 if (temp != (rtx) (HOST_WIDE_INT) - 1)
2293 /* Figure out the amount to which the stack should be aligned. */
2294 #ifdef PREFERRED_STACK_BOUNDARY
2295 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2297 preferred_stack_boundary = STACK_BOUNDARY;
2300 /* Operand 0 is a pointer-to-function; get the type of the function. */
2301 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
2302 if (! POINTER_TYPE_P (funtype))
2304 funtype = TREE_TYPE (funtype);
2306 /* See if this is a call to a function that can return more than once
2307 or a call to longjmp or malloc. */
2308 flags |= special_function_p (fndecl, flags);
2310 if (flags & ECF_MAY_BE_ALLOCA)
2311 current_function_calls_alloca = 1;
2313 /* If struct_value_rtx is 0, it means pass the address
2314 as if it were an extra parameter. */
2315 if (structure_value_addr && struct_value_rtx == 0)
2317 /* If structure_value_addr is a REG other than
2318 virtual_outgoing_args_rtx, we can use always use it. If it
2319 is not a REG, we must always copy it into a register.
2320 If it is virtual_outgoing_args_rtx, we must copy it to another
2321 register in some cases. */
2322 rtx temp = (GET_CODE (structure_value_addr) != REG
2323 || (ACCUMULATE_OUTGOING_ARGS
2324 && stack_arg_under_construction
2325 && structure_value_addr == virtual_outgoing_args_rtx)
2326 ? copy_addr_to_reg (structure_value_addr)
2327 : structure_value_addr);
2330 = tree_cons (error_mark_node,
2331 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2334 structure_value_addr_parm = 1;
2337 /* Count the arguments and set NUM_ACTUALS. */
2338 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2341 /* Compute number of named args.
2342 Normally, don't include the last named arg if anonymous args follow.
2343 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2344 (If no anonymous args follow, the result of list_length is actually
2345 one too large. This is harmless.)
2347 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2348 zero, this machine will be able to place unnamed args that were
2349 passed in registers into the stack. So treat all args as named.
2350 This allows the insns emitting for a specific argument list to be
2351 independent of the function declaration.
2353 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2354 reliable way to pass unnamed args in registers, so we must force
2355 them into memory. */
2357 if ((STRICT_ARGUMENT_NAMING
2358 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2359 && TYPE_ARG_TYPES (funtype) != 0)
2361 = (list_length (TYPE_ARG_TYPES (funtype))
2362 /* Don't include the last named arg. */
2363 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2364 /* Count the struct value address, if it is passed as a parm. */
2365 + structure_value_addr_parm);
2367 /* If we know nothing, treat all args as named. */
2368 n_named_args = num_actuals;
2370 /* Start updating where the next arg would go.
2372 On some machines (such as the PA) indirect calls have a different
2373 calling convention than normal calls. The last argument in
2374 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2376 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
2378 /* Make a vector to hold all the information about each arg. */
2379 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
2380 bzero ((char *) args, num_actuals * sizeof (struct arg_data));
2382 /* Build up entries inthe ARGS array, compute the size of the arguments
2383 into ARGS_SIZE, etc. */
2384 initialize_argument_information (num_actuals, args, &args_size,
2385 n_named_args, actparms, fndecl,
2386 &args_so_far, reg_parm_stack_space,
2387 &old_stack_level, &old_pending_adj,
2388 &must_preallocate, &flags);
2392 /* If this function requires a variable-sized argument list, don't
2393 try to make a cse'able block for this call. We may be able to
2394 do this eventually, but it is too complicated to keep track of
2395 what insns go in the cse'able block and which don't. */
2397 flags &= ~(ECF_CONST | ECF_PURE);
2398 must_preallocate = 1;
2401 /* Now make final decision about preallocating stack space. */
2402 must_preallocate = finalize_must_preallocate (must_preallocate,
2406 /* If the structure value address will reference the stack pointer, we
2407 must stabilize it. We don't need to do this if we know that we are
2408 not going to adjust the stack pointer in processing this call. */
2410 if (structure_value_addr
2411 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2412 || reg_mentioned_p (virtual_outgoing_args_rtx,
2413 structure_value_addr))
2415 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2416 structure_value_addr = copy_to_reg (structure_value_addr);
2418 /* Tail calls can make things harder to debug, and we're traditionally
2419 pushed these optimizations into -O2. Don't try if we're already
2420 expanding a call, as that means we're an argument. Similarly, if
2421 there's pending loops or cleanups we know there's code to follow
2424 If rtx_equal_function_value_matters is false, that means we've
2425 finished with regular parsing. Which means that some of the
2426 machinery we use to generate tail-calls is no longer in place.
2427 This is most often true of sjlj-exceptions, which we couldn't
2428 tail-call to anyway. */
2430 if (currently_expanding_call++ != 0
2431 || !flag_optimize_sibling_calls
2432 || !rtx_equal_function_value_matters
2433 || !stmt_loop_nest_empty ()
2434 || any_pending_cleanups (1)
2436 try_tail_call = try_tail_recursion = 0;
2438 /* Tail recursion fails, when we are not dealing with recursive calls. */
2439 if (!try_tail_recursion
2440 || TREE_CODE (TREE_OPERAND (exp, 0)) != ADDR_EXPR
2441 || TREE_OPERAND (TREE_OPERAND (exp, 0), 0) != current_function_decl)
2442 try_tail_recursion = 0;
2444 /* Rest of purposes for tail call optimizations to fail. */
2446 #ifdef HAVE_sibcall_epilogue
2447 !HAVE_sibcall_epilogue
2452 /* Doing sibling call optimization needs some work, since
2453 structure_value_addr can be allocated on the stack.
2454 It does not seem worth the effort since few optimizable
2455 sibling calls will return a structure. */
2456 || structure_value_addr != NULL_RTX
2457 /* If the register holding the address is a callee saved
2458 register, then we lose. We have no way to prevent that,
2459 so we only allow calls to named functions. */
2460 /* ??? This could be done by having the insn constraints
2461 use a register class that is all call-clobbered. Any
2462 reload insns generated to fix things up would appear
2463 before the sibcall_epilogue. */
2464 || fndecl == NULL_TREE
2465 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP))
2466 || !FUNCTION_OK_FOR_SIBCALL (fndecl)
2467 /* If this function requires more stack slots than the current
2468 function, we cannot change it into a sibling call. */
2469 || args_size.constant > current_function_args_size
2470 /* If the callee pops its own arguments, then it must pop exactly
2471 the same number of arguments as the current function. */
2472 || RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2473 != RETURN_POPS_ARGS (current_function_decl,
2474 TREE_TYPE (current_function_decl),
2475 current_function_args_size))
2478 if (try_tail_call || try_tail_recursion)
2481 actparms = NULL_TREE;
2482 /* Ok, we're going to give the tail call the old college try.
2483 This means we're going to evaluate the function arguments
2484 up to three times. There are two degrees of badness we can
2485 encounter, those that can be unsaved and those that can't.
2486 (See unsafe_for_reeval commentary for details.)
2488 Generate a new argument list. Pass safe arguments through
2489 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2490 For hard badness, evaluate them now and put their resulting
2491 rtx in a temporary VAR_DECL.
2493 initialize_argument_information has ordered the array for the
2494 order to be pushed, and we must remember this when reconstructing
2495 the original argument orde. */
2497 if (PUSH_ARGS_REVERSED)
2506 i = num_actuals - 1;
2510 for (; i != end; i += inc)
2512 switch (unsafe_for_reeval (args[i].tree_value))
2517 case 1: /* Mildly unsafe. */
2518 args[i].tree_value = unsave_expr (args[i].tree_value);
2521 case 2: /* Wildly unsafe. */
2523 tree var = build_decl (VAR_DECL, NULL_TREE,
2524 TREE_TYPE (args[i].tree_value));
2525 DECL_RTL (var) = expand_expr (args[i].tree_value, NULL_RTX,
2526 VOIDmode, EXPAND_NORMAL);
2527 args[i].tree_value = var;
2534 /* We need to build actparms for optimize_tail_recursion. We can
2535 safely trash away TREE_PURPOSE, since it is unused by this
2537 if (try_tail_recursion)
2538 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2540 /* Expanding one of those dangerous arguments could have added
2541 cleanups, but otherwise give it a whirl. */
2542 if (any_pending_cleanups (1))
2543 try_tail_call = try_tail_recursion = 0;
2546 /* Generate a tail recursion sequence when calling ourselves. */
2548 if (try_tail_recursion)
2550 /* We want to emit any pending stack adjustments before the tail
2551 recursion "call". That way we know any adjustment after the tail
2552 recursion call can be ignored if we indeed use the tail recursion
2554 int save_pending_stack_adjust = pending_stack_adjust;
2555 int save_stack_pointer_delta = stack_pointer_delta;
2557 /* Use a new sequence to hold any RTL we generate. We do not even
2558 know if we will use this RTL yet. The final decision can not be
2559 made until after RTL generation for the entire function is
2562 /* If expanding any of the arguments creates cleanups, we can't
2563 do a tailcall. So, we'll need to pop the pending cleanups
2564 list. If, however, all goes well, and there are no cleanups
2565 then the call to expand_start_target_temps will have no
2567 expand_start_target_temps ();
2568 if (optimize_tail_recursion (actparms, get_last_insn ()))
2570 if (any_pending_cleanups (1))
2571 try_tail_call = try_tail_recursion = 0;
2573 tail_recursion_insns = get_insns ();
2575 expand_end_target_temps ();
2578 /* Restore the original pending stack adjustment for the sibling and
2579 normal call cases below. */
2580 pending_stack_adjust = save_pending_stack_adjust;
2581 stack_pointer_delta = save_stack_pointer_delta;
2584 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2586 /* A fork duplicates the profile information, and an exec discards
2587 it. We can't rely on fork/exec to be paired. So write out the
2588 profile information we have gathered so far, and clear it. */
2589 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2590 is subject to race conditions, just as with multithreaded
2593 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__bb_fork_func"), 0,
2597 /* Ensure current function's preferred stack boundary is at least
2598 what we need. We don't have to increase alignment for recursive
2600 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2601 && fndecl != current_function_decl)
2602 cfun->preferred_stack_boundary = preferred_stack_boundary;
2604 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2606 function_call_count++;
2608 /* We want to make two insn chains; one for a sibling call, the other
2609 for a normal call. We will select one of the two chains after
2610 initial RTL generation is complete. */
2611 for (pass = 0; pass < 2; pass++)
2613 int sibcall_failure = 0;
2614 /* We want to emit ay pending stack adjustments before the tail
2615 recursion "call". That way we know any adjustment after the tail
2616 recursion call can be ignored if we indeed use the tail recursion
2618 int save_pending_stack_adjust = 0;
2619 int save_stack_pointer_delta = 0;
2621 rtx before_call, next_arg_reg;
2625 if (! try_tail_call)
2628 /* Emit any queued insns now; otherwise they would end up in
2629 only one of the alternates. */
2632 /* State variables we need to save and restore between
2634 save_pending_stack_adjust = pending_stack_adjust;
2635 save_stack_pointer_delta = stack_pointer_delta;
2638 flags &= ~ECF_SIBCALL;
2640 flags |= ECF_SIBCALL;
2642 /* Other state variables that we must reinitialize each time
2643 through the loop (that are not initialized by the loop itself). */
2647 /* Start a new sequence for the normal call case.
2649 From this point on, if the sibling call fails, we want to set
2650 sibcall_failure instead of continuing the loop. */
2655 /* We know at this point that there are not currently any
2656 pending cleanups. If, however, in the process of evaluating
2657 the arguments we were to create some, we'll need to be
2658 able to get rid of them. */
2659 expand_start_target_temps ();
2662 /* When calling a const function, we must pop the stack args right away,
2663 so that the pop is deleted or moved with the call. */
2664 if (flags & (ECF_CONST | ECF_PURE))
2667 /* Don't let pending stack adjusts add up to too much.
2668 Also, do all pending adjustments now if there is any chance
2669 this might be a call to alloca or if we are expanding a sibling
2671 if (pending_stack_adjust >= 32
2672 || (pending_stack_adjust > 0 && (flags & ECF_MAY_BE_ALLOCA))
2674 do_pending_stack_adjust ();
2676 /* Push the temporary stack slot level so that we can free any
2677 temporaries we make. */
2680 #ifdef FINAL_REG_PARM_STACK_SPACE
2681 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2684 /* Precompute any arguments as needed. */
2686 precompute_arguments (flags, num_actuals, args);
2688 /* Now we are about to start emitting insns that can be deleted
2689 if a libcall is deleted. */
2690 if (flags & (ECF_CONST | ECF_PURE | ECF_MALLOC))
2693 adjusted_args_size = args_size;
2694 /* Compute the actual size of the argument block required. The variable
2695 and constant sizes must be combined, the size may have to be rounded,
2696 and there may be a minimum required size. When generating a sibcall
2697 pattern, do not round up, since we'll be re-using whatever space our
2699 unadjusted_args_size
2700 = compute_argument_block_size (reg_parm_stack_space,
2701 &adjusted_args_size,
2703 : preferred_stack_boundary));
2705 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2707 /* The argument block when performing a sibling call is the
2708 incoming argument block. */
2711 argblock = virtual_incoming_args_rtx;
2712 stored_args_map = sbitmap_alloc (args_size.constant);
2713 sbitmap_zero (stored_args_map);
2716 /* If we have no actual push instructions, or shouldn't use them,
2717 make space for all args right now. */
2718 else if (adjusted_args_size.var != 0)
2720 if (old_stack_level == 0)
2722 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2723 old_pending_adj = pending_stack_adjust;
2724 pending_stack_adjust = 0;
2725 /* stack_arg_under_construction says whether a stack arg is
2726 being constructed at the old stack level. Pushing the stack
2727 gets a clean outgoing argument block. */
2728 old_stack_arg_under_construction = stack_arg_under_construction;
2729 stack_arg_under_construction = 0;
2731 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2735 /* Note that we must go through the motions of allocating an argument
2736 block even if the size is zero because we may be storing args
2737 in the area reserved for register arguments, which may be part of
2740 int needed = adjusted_args_size.constant;
2742 /* Store the maximum argument space used. It will be pushed by
2743 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2746 if (needed > current_function_outgoing_args_size)
2747 current_function_outgoing_args_size = needed;
2749 if (must_preallocate)
2751 if (ACCUMULATE_OUTGOING_ARGS)
2753 /* Since the stack pointer will never be pushed, it is
2754 possible for the evaluation of a parm to clobber
2755 something we have already written to the stack.
2756 Since most function calls on RISC machines do not use
2757 the stack, this is uncommon, but must work correctly.
2759 Therefore, we save any area of the stack that was already
2760 written and that we are using. Here we set up to do this
2761 by making a new stack usage map from the old one. The
2762 actual save will be done by store_one_arg.
2764 Another approach might be to try to reorder the argument
2765 evaluations to avoid this conflicting stack usage. */
2767 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2768 /* Since we will be writing into the entire argument area,
2769 the map must be allocated for its entire size, not just
2770 the part that is the responsibility of the caller. */
2771 needed += reg_parm_stack_space;
2774 #ifdef ARGS_GROW_DOWNWARD
2775 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2778 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2782 = (char *) alloca (highest_outgoing_arg_in_use);
2784 if (initial_highest_arg_in_use)
2785 bcopy (initial_stack_usage_map, stack_usage_map,
2786 initial_highest_arg_in_use);
2788 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2789 bzero (&stack_usage_map[initial_highest_arg_in_use],
2790 (highest_outgoing_arg_in_use
2791 - initial_highest_arg_in_use));
2794 /* The address of the outgoing argument list must not be
2795 copied to a register here, because argblock would be left
2796 pointing to the wrong place after the call to
2797 allocate_dynamic_stack_space below. */
2799 argblock = virtual_outgoing_args_rtx;
2803 if (inhibit_defer_pop == 0)
2805 /* Try to reuse some or all of the pending_stack_adjust
2806 to get this space. */
2808 = (combine_pending_stack_adjustment_and_call
2809 (unadjusted_args_size,
2810 &adjusted_args_size,
2811 preferred_unit_stack_boundary));
2813 /* combine_pending_stack_adjustment_and_call computes
2814 an adjustment before the arguments are allocated.
2815 Account for them and see whether or not the stack
2816 needs to go up or down. */
2817 needed = unadjusted_args_size - needed;
2821 /* We're releasing stack space. */
2822 /* ??? We can avoid any adjustment at all if we're
2823 already aligned. FIXME. */
2824 pending_stack_adjust = -needed;
2825 do_pending_stack_adjust ();
2829 /* We need to allocate space. We'll do that in
2830 push_block below. */
2831 pending_stack_adjust = 0;
2834 /* Special case this because overhead of `push_block' in
2835 this case is non-trivial. */
2837 argblock = virtual_outgoing_args_rtx;
2839 argblock = push_block (GEN_INT (needed), 0, 0);
2841 /* We only really need to call `copy_to_reg' in the case
2842 where push insns are going to be used to pass ARGBLOCK
2843 to a function call in ARGS. In that case, the stack
2844 pointer changes value from the allocation point to the
2845 call point, and hence the value of
2846 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2847 as well always do it. */
2848 argblock = copy_to_reg (argblock);
2850 /* The save/restore code in store_one_arg handles all
2851 cases except one: a constructor call (including a C
2852 function returning a BLKmode struct) to initialize
2854 if (stack_arg_under_construction)
2856 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2857 rtx push_size = GEN_INT (reg_parm_stack_space
2858 + adjusted_args_size.constant);
2860 rtx push_size = GEN_INT (adjusted_args_size.constant);
2862 if (old_stack_level == 0)
2864 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2866 old_pending_adj = pending_stack_adjust;
2867 pending_stack_adjust = 0;
2868 /* stack_arg_under_construction says whether a stack
2869 arg is being constructed at the old stack level.
2870 Pushing the stack gets a clean outgoing argument
2872 old_stack_arg_under_construction
2873 = stack_arg_under_construction;
2874 stack_arg_under_construction = 0;
2875 /* Make a new map for the new argument list. */
2876 stack_usage_map = (char *)
2877 alloca (highest_outgoing_arg_in_use);
2878 bzero (stack_usage_map, highest_outgoing_arg_in_use);
2879 highest_outgoing_arg_in_use = 0;
2881 allocate_dynamic_stack_space (push_size, NULL_RTX,
2884 /* If argument evaluation might modify the stack pointer,
2885 copy the address of the argument list to a register. */
2886 for (i = 0; i < num_actuals; i++)
2887 if (args[i].pass_on_stack)
2889 argblock = copy_addr_to_reg (argblock);
2896 compute_argument_addresses (args, argblock, num_actuals);
2898 #ifdef PREFERRED_STACK_BOUNDARY
2899 /* If we push args individually in reverse order, perform stack alignment
2900 before the first push (the last arg). */
2901 if (PUSH_ARGS_REVERSED && argblock == 0
2902 && adjusted_args_size.constant != unadjusted_args_size)
2904 /* When the stack adjustment is pending, we get better code
2905 by combining the adjustments. */
2906 if (pending_stack_adjust
2907 && ! (flags & (ECF_CONST | ECF_PURE))
2908 && ! inhibit_defer_pop)
2910 pending_stack_adjust
2911 = (combine_pending_stack_adjustment_and_call
2912 (unadjusted_args_size,
2913 &adjusted_args_size,
2914 preferred_unit_stack_boundary));
2915 do_pending_stack_adjust ();
2917 else if (argblock == 0)
2918 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2919 - unadjusted_args_size));
2921 /* Now that the stack is properly aligned, pops can't safely
2922 be deferred during the evaluation of the arguments. */
2926 /* Don't try to defer pops if preallocating, not even from the first arg,
2927 since ARGBLOCK probably refers to the SP. */
2931 funexp = rtx_for_function_call (fndecl, exp);
2933 /* Figure out the register where the value, if any, will come back. */
2935 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2936 && ! structure_value_addr)
2938 if (pcc_struct_value)
2939 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2940 fndecl, (pass == 0));
2942 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2945 /* Precompute all register parameters. It isn't safe to compute anything
2946 once we have started filling any specific hard regs. */
2947 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2949 #ifdef REG_PARM_STACK_SPACE
2950 /* Save the fixed argument area if it's part of the caller's frame and
2951 is clobbered by argument setup for this call. */
2952 if (ACCUMULATE_OUTGOING_ARGS && pass)
2953 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2954 &low_to_save, &high_to_save);
2957 /* Now store (and compute if necessary) all non-register parms.
2958 These come before register parms, since they can require block-moves,
2959 which could clobber the registers used for register parms.
2960 Parms which have partial registers are not stored here,
2961 but we do preallocate space here if they want that. */
2963 for (i = 0; i < num_actuals; i++)
2964 if (args[i].reg == 0 || args[i].pass_on_stack)
2966 rtx before_arg = get_last_insn ();
2968 if (store_one_arg (&args[i], argblock, flags,
2969 adjusted_args_size.var != 0,
2970 reg_parm_stack_space)
2972 && check_sibcall_argument_overlap (before_arg,
2974 sibcall_failure = 1;
2977 /* If we have a parm that is passed in registers but not in memory
2978 and whose alignment does not permit a direct copy into registers,
2979 make a group of pseudos that correspond to each register that we
2981 if (STRICT_ALIGNMENT)
2982 store_unaligned_arguments_into_pseudos (args, num_actuals);
2984 /* Now store any partially-in-registers parm.
2985 This is the last place a block-move can happen. */
2987 for (i = 0; i < num_actuals; i++)
2988 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2990 rtx before_arg = get_last_insn ();
2992 if (store_one_arg (&args[i], argblock, flags,
2993 adjusted_args_size.var != 0,
2994 reg_parm_stack_space)
2996 && check_sibcall_argument_overlap (before_arg,
2998 sibcall_failure = 1;
3001 #ifdef PREFERRED_STACK_BOUNDARY
3002 /* If we pushed args in forward order, perform stack alignment
3003 after pushing the last arg. */
3004 if (!PUSH_ARGS_REVERSED && argblock == 0)
3005 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3006 - unadjusted_args_size));
3009 /* If register arguments require space on the stack and stack space
3010 was not preallocated, allocate stack space here for arguments
3011 passed in registers. */
3012 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3013 if (!ACCUMULATE_OUTGOING_ARGS
3014 && must_preallocate == 0 && reg_parm_stack_space > 0)
3015 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3018 /* Pass the function the address in which to return a
3020 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3022 emit_move_insn (struct_value_rtx,
3024 force_operand (structure_value_addr,
3027 /* Mark the memory for the aggregate as write-only. */
3028 if (current_function_check_memory_usage)
3029 emit_library_call (chkr_set_right_libfunc, 1,
3031 structure_value_addr, ptr_mode,
3032 GEN_INT (struct_value_size),
3033 TYPE_MODE (sizetype),
3034 GEN_INT (MEMORY_USE_WO),
3035 TYPE_MODE (integer_type_node));
3037 if (GET_CODE (struct_value_rtx) == REG)
3038 use_reg (&call_fusage, struct_value_rtx);
3041 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3044 load_register_parameters (args, num_actuals, &call_fusage, flags);
3046 /* Perform postincrements before actually calling the function. */
3049 /* Save a pointer to the last insn before the call, so that we can
3050 later safely search backwards to find the CALL_INSN. */
3051 before_call = get_last_insn ();
3053 /* Set up next argument register. For sibling calls on machines
3054 with register windows this should be the incoming register. */
3055 #ifdef FUNCTION_INCOMING_ARG
3057 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3061 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3064 /* All arguments and registers used for the call must be set up by
3067 #ifdef PREFERRED_STACK_BOUNDARY
3068 /* Stack must be properly aligned now. */
3069 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3073 /* Generate the actual call instruction. */
3074 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3075 adjusted_args_size.constant, struct_value_size,
3076 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3079 /* Verify that we've deallocated all the stack we used. */
3081 && old_stack_allocated != stack_pointer_delta - pending_stack_adjust)
3084 /* If call is cse'able, make appropriate pair of reg-notes around it.
3085 Test valreg so we don't crash; may safely ignore `const'
3086 if return type is void. Disable for PARALLEL return values, because
3087 we have no way to move such values into a pseudo register. */
3089 && (flags & (ECF_CONST | ECF_PURE))
3090 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
3093 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3096 /* Mark the return value as a pointer if needed. */
3097 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3098 mark_reg_pointer (temp, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3100 /* Construct an "equal form" for the value which mentions all the
3101 arguments in order as well as the function name. */
3102 for (i = 0; i < num_actuals; i++)
3103 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
3104 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3106 insns = get_insns ();
3109 if (flags & ECF_PURE)
3110 note = gen_rtx_EXPR_LIST (VOIDmode,
3111 gen_rtx_USE (VOIDmode,
3112 gen_rtx_MEM (BLKmode,
3113 gen_rtx_SCRATCH (VOIDmode))), note);
3115 emit_libcall_block (insns, temp, valreg, note);
3119 else if (flags & (ECF_CONST | ECF_PURE))
3121 /* Otherwise, just write out the sequence without a note. */
3122 rtx insns = get_insns ();
3127 else if (flags & ECF_MALLOC)
3129 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3132 /* The return value from a malloc-like function is a pointer. */
3133 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3134 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3136 emit_move_insn (temp, valreg);
3138 /* The return value from a malloc-like function can not alias
3140 last = get_last_insn ();
3142 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3144 /* Write out the sequence. */
3145 insns = get_insns ();
3151 /* For calls to `setjmp', etc., inform flow.c it should complain
3152 if nonvolatile values are live. For functions that cannot return,
3153 inform flow that control does not fall through. */
3155 if ((flags & (ECF_RETURNS_TWICE | ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3157 /* The barrier or NOTE_INSN_SETJMP note must be emitted
3158 immediately after the CALL_INSN. Some ports emit more
3159 than just a CALL_INSN above, so we must search for it here. */
3161 rtx last = get_last_insn ();
3162 while (GET_CODE (last) != CALL_INSN)
3164 last = PREV_INSN (last);
3165 /* There was no CALL_INSN? */
3166 if (last == before_call)
3170 if (flags & ECF_RETURNS_TWICE)
3172 emit_note_after (NOTE_INSN_SETJMP, last);
3173 current_function_calls_setjmp = 1;
3176 emit_barrier_after (last);
3179 if (flags & ECF_LONGJMP)
3180 current_function_calls_longjmp = 1;
3182 /* If this function is returning into a memory location marked as
3183 readonly, it means it is initializing that location. But we normally
3184 treat functions as not clobbering such locations, so we need to
3185 specify that this one does. */
3186 if (target != 0 && GET_CODE (target) == MEM
3187 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
3188 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
3190 /* If value type not void, return an rtx for the value. */
3192 /* If there are cleanups to be called, don't use a hard reg as target.
3193 We need to double check this and see if it matters anymore. */
3194 if (any_pending_cleanups (1))
3196 if (target && REG_P (target)
3197 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3199 sibcall_failure = 1;
3202 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3205 target = const0_rtx;
3207 else if (structure_value_addr)
3209 if (target == 0 || GET_CODE (target) != MEM)
3212 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3213 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3214 structure_value_addr));
3215 set_mem_attributes (target, exp, 1);
3218 else if (pcc_struct_value)
3220 /* This is the special C++ case where we need to
3221 know what the true target was. We take care to
3222 never use this value more than once in one expression. */
3223 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3224 copy_to_reg (valreg));
3225 set_mem_attributes (target, exp, 1);
3227 /* Handle calls that return values in multiple non-contiguous locations.
3228 The Irix 6 ABI has examples of this. */
3229 else if (GET_CODE (valreg) == PARALLEL)
3231 int bytes = int_size_in_bytes (TREE_TYPE (exp));
3235 target = assign_stack_temp (TYPE_MODE (TREE_TYPE (exp)),
3237 MEM_SET_IN_STRUCT_P (target, AGGREGATE_TYPE_P (TREE_TYPE (exp)));
3238 preserve_temp_slots (target);
3241 if (! rtx_equal_p (target, valreg))
3242 emit_group_store (target, valreg, bytes,
3243 TYPE_ALIGN (TREE_TYPE (exp)));
3245 /* We can not support sibling calls for this case. */
3246 sibcall_failure = 1;
3249 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3250 && GET_MODE (target) == GET_MODE (valreg))
3252 /* TARGET and VALREG cannot be equal at this point because the
3253 latter would not have REG_FUNCTION_VALUE_P true, while the
3254 former would if it were referring to the same register.
3256 If they refer to the same register, this move will be a no-op,
3257 except when function inlining is being done. */
3258 emit_move_insn (target, valreg);
3260 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3261 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3263 target = copy_to_reg (valreg);
3265 #ifdef PROMOTE_FUNCTION_RETURN
3266 /* If we promoted this return value, make the proper SUBREG. TARGET
3267 might be const0_rtx here, so be careful. */
3268 if (GET_CODE (target) == REG
3269 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3270 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3272 tree type = TREE_TYPE (exp);
3273 int unsignedp = TREE_UNSIGNED (type);
3275 /* If we don't promote as expected, something is wrong. */
3276 if (GET_MODE (target)
3277 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3280 target = gen_rtx_SUBREG (TYPE_MODE (type), target, 0);
3281 SUBREG_PROMOTED_VAR_P (target) = 1;
3282 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
3286 /* If size of args is variable or this was a constructor call for a stack
3287 argument, restore saved stack-pointer value. */
3289 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3291 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3292 pending_stack_adjust = old_pending_adj;
3293 stack_arg_under_construction = old_stack_arg_under_construction;
3294 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3295 stack_usage_map = initial_stack_usage_map;
3296 sibcall_failure = 1;
3298 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3300 #ifdef REG_PARM_STACK_SPACE
3303 restore_fixed_argument_area (save_area, argblock,
3304 high_to_save, low_to_save);
3308 /* If we saved any argument areas, restore them. */
3309 for (i = 0; i < num_actuals; i++)
3310 if (args[i].save_area)
3312 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3314 = gen_rtx_MEM (save_mode,
3315 memory_address (save_mode,
3316 XEXP (args[i].stack_slot, 0)));
3318 if (save_mode != BLKmode)
3319 emit_move_insn (stack_area, args[i].save_area);
3321 emit_block_move (stack_area,
3322 validize_mem (args[i].save_area),
3323 GEN_INT (args[i].size.constant),
3327 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3328 stack_usage_map = initial_stack_usage_map;
3331 /* If this was alloca, record the new stack level for nonlocal gotos.
3332 Check for the handler slots since we might not have a save area
3333 for non-local gotos. */
3335 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3336 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3340 /* Free up storage we no longer need. */
3341 for (i = 0; i < num_actuals; ++i)
3342 if (args[i].aligned_regs)
3343 free (args[i].aligned_regs);
3347 /* Undo the fake expand_start_target_temps we did earlier. If
3348 there had been any cleanups created, we've already set
3350 expand_end_target_temps ();
3353 insns = get_insns ();
3358 tail_call_insns = insns;
3360 /* If something prevents making this a sibling call,
3361 zero out the sequence. */
3362 if (sibcall_failure)
3363 tail_call_insns = NULL_RTX;
3364 /* Restore the pending stack adjustment now that we have
3365 finished generating the sibling call sequence. */
3367 pending_stack_adjust = save_pending_stack_adjust;
3368 stack_pointer_delta = save_stack_pointer_delta;
3370 /* Prepare arg structure for next iteration. */
3371 for (i = 0; i < num_actuals; i++)
3374 args[i].aligned_regs = 0;
3378 sbitmap_free (stored_args_map);
3381 normal_call_insns = insns;
3384 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3385 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3386 can happen if the arguments to this function call an inline
3387 function who's expansion contains another CALL_PLACEHOLDER.
3389 If there are any C_Ps in any of these sequences, replace them
3390 with their normal call. */
3392 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3393 if (GET_CODE (insn) == CALL_INSN
3394 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3395 replace_call_placeholder (insn, sibcall_use_normal);
3397 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3398 if (GET_CODE (insn) == CALL_INSN
3399 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3400 replace_call_placeholder (insn, sibcall_use_normal);
3402 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3403 if (GET_CODE (insn) == CALL_INSN
3404 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3405 replace_call_placeholder (insn, sibcall_use_normal);
3407 /* If this was a potential tail recursion site, then emit a
3408 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3409 One of them will be selected later. */
3410 if (tail_recursion_insns || tail_call_insns)
3412 /* The tail recursion label must be kept around. We could expose
3413 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3414 and makes determining true tail recursion sites difficult.
3416 So we set LABEL_PRESERVE_P here, then clear it when we select
3417 one of the call sequences after rtl generation is complete. */
3418 if (tail_recursion_insns)
3419 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3420 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3422 tail_recursion_insns,
3423 tail_recursion_label));
3426 emit_insns (normal_call_insns);
3428 currently_expanding_call--;
3430 /* If this function returns with the stack pointer depressed, ensure
3431 this block saves and restores the stack pointer, show it was
3432 changed, and adjust for any outgoing arg space. */
3433 if (flags & ECF_SP_DEPRESSED)
3435 clear_pending_stack_adjust ();
3436 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3437 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3438 save_stack_pointer ();
3444 /* Returns nonzero if FUN is the symbol for a library function which can
3448 libfunc_nothrow (fun)
3451 if (fun == throw_libfunc
3452 || fun == rethrow_libfunc
3453 || fun == sjthrow_libfunc
3454 || fun == sjpopnthrow_libfunc)
3460 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3461 The RETVAL parameter specifies whether return value needs to be saved, other
3462 parameters are documented in the emit_library_call function bellow. */
3464 emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3469 enum machine_mode outmode;
3473 /* Total size in bytes of all the stack-parms scanned so far. */
3474 struct args_size args_size;
3475 /* Size of arguments before any adjustments (such as rounding). */
3476 struct args_size original_args_size;
3477 register int argnum;
3481 struct args_size alignment_pad;
3483 CUMULATIVE_ARGS args_so_far;
3487 enum machine_mode mode;
3490 struct args_size offset;
3491 struct args_size size;
3495 int old_inhibit_defer_pop = inhibit_defer_pop;
3496 rtx call_fusage = 0;
3499 int pcc_struct_value = 0;
3500 int struct_value_size = 0;
3502 int reg_parm_stack_space = 0;
3505 #ifdef REG_PARM_STACK_SPACE
3506 /* Define the boundary of the register parm stack space that needs to be
3508 int low_to_save = -1, high_to_save = 0;
3509 rtx save_area = 0; /* Place that it is saved. */
3512 /* Size of the stack reserved for parameter registers. */
3513 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3514 char *initial_stack_usage_map = stack_usage_map;
3516 #ifdef REG_PARM_STACK_SPACE
3517 #ifdef MAYBE_REG_PARM_STACK_SPACE
3518 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3520 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3526 else if (fn_type == 2)
3530 if (libfunc_nothrow (fun))
3531 flags |= ECF_NOTHROW;
3533 #ifdef PREFERRED_STACK_BOUNDARY
3534 /* Ensure current function's preferred stack boundary is at least
3536 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3537 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3540 /* If this kind of value comes back in memory,
3541 decide where in memory it should come back. */
3542 if (outmode != VOIDmode && aggregate_value_p (type_for_mode (outmode, 0)))
3544 #ifdef PCC_STATIC_STRUCT_RETURN
3546 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
3548 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3549 pcc_struct_value = 1;
3551 value = gen_reg_rtx (outmode);
3552 #else /* not PCC_STATIC_STRUCT_RETURN */
3553 struct_value_size = GET_MODE_SIZE (outmode);
3554 if (value != 0 && GET_CODE (value) == MEM)
3557 mem_value = assign_stack_temp (outmode, GET_MODE_SIZE (outmode), 0);
3560 /* This call returns a big structure. */
3561 flags &= ~(ECF_CONST | ECF_PURE);
3564 /* ??? Unfinished: must pass the memory address as an argument. */
3566 /* Copy all the libcall-arguments out of the varargs data
3567 and into a vector ARGVEC.
3569 Compute how to pass each argument. We only support a very small subset
3570 of the full argument passing conventions to limit complexity here since
3571 library functions shouldn't have many args. */
3573 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3574 bzero ((char *) argvec, (nargs + 1) * sizeof (struct arg));
3576 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3578 args_size.constant = 0;
3583 /* Now we are about to start emitting insns that can be deleted
3584 if a libcall is deleted. */
3585 if (flags & (ECF_CONST | ECF_PURE))
3590 /* If there's a structure value address to be passed,
3591 either pass it in the special place, or pass it as an extra argument. */
3592 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3594 rtx addr = XEXP (mem_value, 0);
3597 /* Make sure it is a reasonable operand for a move or push insn. */
3598 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3599 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3600 addr = force_operand (addr, NULL_RTX);
3602 argvec[count].value = addr;
3603 argvec[count].mode = Pmode;
3604 argvec[count].partial = 0;
3606 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3607 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3608 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3612 locate_and_pad_parm (Pmode, NULL_TREE,
3613 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3616 argvec[count].reg != 0,
3618 NULL_TREE, &args_size, &argvec[count].offset,
3619 &argvec[count].size, &alignment_pad);
3621 if (argvec[count].reg == 0 || argvec[count].partial != 0
3622 || reg_parm_stack_space > 0)
3623 args_size.constant += argvec[count].size.constant;
3625 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3630 for (; count < nargs; count++)
3632 rtx val = va_arg (p, rtx);
3633 enum machine_mode mode = va_arg (p, enum machine_mode);
3635 /* We cannot convert the arg value to the mode the library wants here;
3636 must do it earlier where we know the signedness of the arg. */
3638 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3641 /* On some machines, there's no way to pass a float to a library fcn.
3642 Pass it as a double instead. */
3643 #ifdef LIBGCC_NEEDS_DOUBLE
3644 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3645 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3648 /* There's no need to call protect_from_queue, because
3649 either emit_move_insn or emit_push_insn will do that. */
3651 /* Make sure it is a reasonable operand for a move or push insn. */
3652 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3653 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3654 val = force_operand (val, NULL_RTX);
3656 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3657 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3659 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
3660 be viewed as just an efficiency improvement. */
3661 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
3662 emit_move_insn (slot, val);
3663 val = force_operand (XEXP (slot, 0), NULL_RTX);
3668 argvec[count].value = val;
3669 argvec[count].mode = mode;
3671 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3673 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3674 argvec[count].partial
3675 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3677 argvec[count].partial = 0;
3680 locate_and_pad_parm (mode, NULL_TREE,
3681 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3684 argvec[count].reg != 0,
3686 NULL_TREE, &args_size, &argvec[count].offset,
3687 &argvec[count].size, &alignment_pad);
3689 if (argvec[count].size.var)
3692 if (reg_parm_stack_space == 0 && argvec[count].partial)
3693 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3695 if (argvec[count].reg == 0 || argvec[count].partial != 0
3696 || reg_parm_stack_space > 0)
3697 args_size.constant += argvec[count].size.constant;
3699 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3702 #ifdef FINAL_REG_PARM_STACK_SPACE
3703 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3706 /* If this machine requires an external definition for library
3707 functions, write one out. */
3708 assemble_external_libcall (fun);
3710 original_args_size = args_size;
3711 #ifdef PREFERRED_STACK_BOUNDARY
3712 args_size.constant = (((args_size.constant
3713 + stack_pointer_delta
3717 - stack_pointer_delta);
3720 args_size.constant = MAX (args_size.constant,
3721 reg_parm_stack_space);
3723 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3724 args_size.constant -= reg_parm_stack_space;
3727 if (args_size.constant > current_function_outgoing_args_size)
3728 current_function_outgoing_args_size = args_size.constant;
3730 if (ACCUMULATE_OUTGOING_ARGS)
3732 /* Since the stack pointer will never be pushed, it is possible for
3733 the evaluation of a parm to clobber something we have already
3734 written to the stack. Since most function calls on RISC machines
3735 do not use the stack, this is uncommon, but must work correctly.
3737 Therefore, we save any area of the stack that was already written
3738 and that we are using. Here we set up to do this by making a new
3739 stack usage map from the old one.
3741 Another approach might be to try to reorder the argument
3742 evaluations to avoid this conflicting stack usage. */
3744 needed = args_size.constant;
3746 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3747 /* Since we will be writing into the entire argument area, the
3748 map must be allocated for its entire size, not just the part that
3749 is the responsibility of the caller. */
3750 needed += reg_parm_stack_space;
3753 #ifdef ARGS_GROW_DOWNWARD
3754 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3757 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3760 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3762 if (initial_highest_arg_in_use)
3763 bcopy (initial_stack_usage_map, stack_usage_map,
3764 initial_highest_arg_in_use);
3766 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3767 bzero (&stack_usage_map[initial_highest_arg_in_use],
3768 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3771 /* The address of the outgoing argument list must not be copied to a
3772 register here, because argblock would be left pointing to the
3773 wrong place after the call to allocate_dynamic_stack_space below. */
3775 argblock = virtual_outgoing_args_rtx;
3780 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3783 #ifdef PREFERRED_STACK_BOUNDARY
3784 /* If we push args individually in reverse order, perform stack alignment
3785 before the first push (the last arg). */
3786 if (argblock == 0 && PUSH_ARGS_REVERSED)
3787 anti_adjust_stack (GEN_INT (args_size.constant
3788 - original_args_size.constant));
3791 if (PUSH_ARGS_REVERSED)
3802 #ifdef REG_PARM_STACK_SPACE
3803 if (ACCUMULATE_OUTGOING_ARGS)
3805 /* The argument list is the property of the called routine and it
3806 may clobber it. If the fixed area has been used for previous
3807 parameters, we must save and restore it.
3809 Here we compute the boundary of the that needs to be saved, if any. */
3811 #ifdef ARGS_GROW_DOWNWARD
3812 for (count = 0; count < reg_parm_stack_space + 1; count++)
3814 for (count = 0; count < reg_parm_stack_space; count++)
3817 if (count >= highest_outgoing_arg_in_use
3818 || stack_usage_map[count] == 0)
3821 if (low_to_save == -1)
3822 low_to_save = count;
3824 high_to_save = count;
3827 if (low_to_save >= 0)
3829 int num_to_save = high_to_save - low_to_save + 1;
3830 enum machine_mode save_mode
3831 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3834 /* If we don't have the required alignment, must do this in BLKmode. */
3835 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3836 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3837 save_mode = BLKmode;
3839 #ifdef ARGS_GROW_DOWNWARD
3840 stack_area = gen_rtx_MEM (save_mode,
3841 memory_address (save_mode,
3842 plus_constant (argblock,
3845 stack_area = gen_rtx_MEM (save_mode,
3846 memory_address (save_mode,
3847 plus_constant (argblock,
3850 if (save_mode == BLKmode)
3852 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3853 emit_block_move (validize_mem (save_area), stack_area,
3854 GEN_INT (num_to_save), PARM_BOUNDARY);
3858 save_area = gen_reg_rtx (save_mode);
3859 emit_move_insn (save_area, stack_area);
3865 /* Push the args that need to be pushed. */
3867 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3868 are to be pushed. */
3869 for (count = 0; count < nargs; count++, argnum += inc)
3871 register enum machine_mode mode = argvec[argnum].mode;
3872 register rtx val = argvec[argnum].value;
3873 rtx reg = argvec[argnum].reg;
3874 int partial = argvec[argnum].partial;
3875 int lower_bound = 0, upper_bound = 0, i;
3877 if (! (reg != 0 && partial == 0))
3879 if (ACCUMULATE_OUTGOING_ARGS)
3881 /* If this is being stored into a pre-allocated, fixed-size,
3882 stack area, save any previous data at that location. */
3884 #ifdef ARGS_GROW_DOWNWARD
3885 /* stack_slot is negative, but we want to index stack_usage_map
3886 with positive values. */
3887 upper_bound = -argvec[argnum].offset.constant + 1;
3888 lower_bound = upper_bound - argvec[argnum].size.constant;
3890 lower_bound = argvec[argnum].offset.constant;
3891 upper_bound = lower_bound + argvec[argnum].size.constant;
3894 for (i = lower_bound; i < upper_bound; i++)
3895 if (stack_usage_map[i]
3896 /* Don't store things in the fixed argument area at this
3897 point; it has already been saved. */
3898 && i > reg_parm_stack_space)
3901 if (i != upper_bound)
3903 /* We need to make a save area. See what mode we can make
3905 enum machine_mode save_mode
3906 = mode_for_size (argvec[argnum].size.constant
3914 plus_constant (argblock,
3915 argvec[argnum].offset.constant)));
3916 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3918 emit_move_insn (argvec[argnum].save_area, stack_area);
3922 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
3923 argblock, GEN_INT (argvec[argnum].offset.constant),
3924 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3926 /* Now mark the segment we just used. */
3927 if (ACCUMULATE_OUTGOING_ARGS)
3928 for (i = lower_bound; i < upper_bound; i++)
3929 stack_usage_map[i] = 1;
3935 #ifdef PREFERRED_STACK_BOUNDARY
3936 /* If we pushed args in forward order, perform stack alignment
3937 after pushing the last arg. */
3938 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3939 anti_adjust_stack (GEN_INT (args_size.constant
3940 - original_args_size.constant));
3943 if (PUSH_ARGS_REVERSED)
3948 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
3950 /* Now load any reg parms into their regs. */
3952 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3953 are to be pushed. */
3954 for (count = 0; count < nargs; count++, argnum += inc)
3956 register rtx val = argvec[argnum].value;
3957 rtx reg = argvec[argnum].reg;
3958 int partial = argvec[argnum].partial;
3960 /* Handle calls that pass values in multiple non-contiguous
3961 locations. The PA64 has examples of this for library calls. */
3962 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3963 emit_group_load (reg, val,
3964 GET_MODE_SIZE (GET_MODE (val)),
3965 GET_MODE_ALIGNMENT (GET_MODE (val)));
3966 else if (reg != 0 && partial == 0)
3967 emit_move_insn (reg, val);
3972 /* Any regs containing parms remain in use through the call. */
3973 for (count = 0; count < nargs; count++)
3975 rtx reg = argvec[count].reg;
3976 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3977 use_group_regs (&call_fusage, reg);
3979 use_reg (&call_fusage, reg);
3982 /* Pass the function the address in which to return a structure value. */
3983 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
3985 emit_move_insn (struct_value_rtx,
3987 force_operand (XEXP (mem_value, 0),
3989 if (GET_CODE (struct_value_rtx) == REG)
3990 use_reg (&call_fusage, struct_value_rtx);
3993 /* Don't allow popping to be deferred, since then
3994 cse'ing of library calls could delete a call and leave the pop. */
3996 valreg = (mem_value == 0 && outmode != VOIDmode
3997 ? hard_libcall_value (outmode) : NULL_RTX);
3999 #ifdef PREFERRED_STACK_BOUNDARY
4000 /* Stack must be properly aligned now. */
4001 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4005 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4006 will set inhibit_defer_pop to that value. */
4007 /* The return type is needed to decide how many bytes the function pops.
4008 Signedness plays no role in that, so for simplicity, we pretend it's
4009 always signed. We also assume that the list of arguments passed has
4010 no impact, so we pretend it is unknown. */
4013 get_identifier (XSTR (orgfun, 0)),
4014 build_function_type (outmode == VOIDmode ? void_type_node
4015 : type_for_mode (outmode, 0), NULL_TREE),
4016 original_args_size.constant, args_size.constant,
4018 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4020 old_inhibit_defer_pop + 1, call_fusage, flags);
4022 /* Now restore inhibit_defer_pop to its actual original value. */
4025 /* If call is cse'able, make appropriate pair of reg-notes around it.
4026 Test valreg so we don't crash; may safely ignore `const'
4027 if return type is void. Disable for PARALLEL return values, because
4028 we have no way to move such values into a pseudo register. */
4029 if ((flags & (ECF_CONST | ECF_PURE))
4030 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
4033 rtx temp = gen_reg_rtx (GET_MODE (valreg));
4037 /* Construct an "equal form" for the value which mentions all the
4038 arguments in order as well as the function name. */
4039 for (i = 0; i < nargs; i++)
4040 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4041 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4043 insns = get_insns ();
4046 if (flags & ECF_PURE)
4047 note = gen_rtx_EXPR_LIST (VOIDmode,
4048 gen_rtx_USE (VOIDmode,
4049 gen_rtx_MEM (BLKmode,
4050 gen_rtx_SCRATCH (VOIDmode))), note);
4052 emit_libcall_block (insns, temp, valreg, note);
4056 else if (flags & (ECF_CONST | ECF_PURE))
4058 /* Otherwise, just write out the sequence without a note. */
4059 rtx insns = get_insns ();
4066 /* Copy the value to the right place. */
4067 if (outmode != VOIDmode && retval)
4073 if (value != mem_value)
4074 emit_move_insn (value, mem_value);
4076 else if (value != 0)
4077 emit_move_insn (value, hard_libcall_value (outmode));
4079 value = hard_libcall_value (outmode);
4082 if (ACCUMULATE_OUTGOING_ARGS)
4084 #ifdef REG_PARM_STACK_SPACE
4087 enum machine_mode save_mode = GET_MODE (save_area);
4088 #ifdef ARGS_GROW_DOWNWARD
4090 = gen_rtx_MEM (save_mode,
4091 memory_address (save_mode,
4092 plus_constant (argblock,
4096 = gen_rtx_MEM (save_mode,
4097 memory_address (save_mode,
4098 plus_constant (argblock, low_to_save)));
4100 if (save_mode != BLKmode)
4101 emit_move_insn (stack_area, save_area);
4103 emit_block_move (stack_area, validize_mem (save_area),
4104 GEN_INT (high_to_save - low_to_save + 1),
4109 /* If we saved any argument areas, restore them. */
4110 for (count = 0; count < nargs; count++)
4111 if (argvec[count].save_area)
4113 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4115 = gen_rtx_MEM (save_mode,
4118 plus_constant (argblock,
4119 argvec[count].offset.constant)));
4121 emit_move_insn (stack_area, argvec[count].save_area);
4124 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4125 stack_usage_map = initial_stack_usage_map;
4132 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4133 (emitting the queue unless NO_QUEUE is nonzero),
4134 for a value of mode OUTMODE,
4135 with NARGS different arguments, passed as alternating rtx values
4136 and machine_modes to convert them to.
4137 The rtx values should have been passed through protect_from_queue already.
4139 FN_TYPE will is zero for `normal' calls, one for `const' calls, wich
4140 which will be enclosed in REG_LIBCALL/REG_RETVAL notes and two for `pure'
4141 calls, that are handled like `const' calls with extra
4142 (use (memory (scratch)). */
4145 emit_library_call VPARAMS((rtx orgfun, int fn_type, enum machine_mode outmode,
4148 #ifndef ANSI_PROTOTYPES
4151 enum machine_mode outmode;
4156 VA_START (p, nargs);
4158 #ifndef ANSI_PROTOTYPES
4159 orgfun = va_arg (p, rtx);
4160 fn_type = va_arg (p, int);
4161 outmode = va_arg (p, enum machine_mode);
4162 nargs = va_arg (p, int);
4165 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4170 /* Like emit_library_call except that an extra argument, VALUE,
4171 comes second and says where to store the result.
4172 (If VALUE is zero, this function chooses a convenient way
4173 to return the value.
4175 This function returns an rtx for where the value is to be found.
4176 If VALUE is nonzero, VALUE is returned. */
4179 emit_library_call_value VPARAMS((rtx orgfun, rtx value, int fn_type,
4180 enum machine_mode outmode, int nargs, ...))
4182 #ifndef ANSI_PROTOTYPES
4186 enum machine_mode outmode;
4191 VA_START (p, nargs);
4193 #ifndef ANSI_PROTOTYPES
4194 orgfun = va_arg (p, rtx);
4195 value = va_arg (p, rtx);
4196 fn_type = va_arg (p, int);
4197 outmode = va_arg (p, enum machine_mode);
4198 nargs = va_arg (p, int);
4201 value = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode, nargs, p);
4209 /* Return an rtx which represents a suitable home on the stack
4210 given TYPE, the type of the argument looking for a home.
4211 This is called only for BLKmode arguments.
4213 SIZE is the size needed for this target.
4214 ARGS_ADDR is the address of the bottom of the argument block for this call.
4215 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
4216 if this machine uses push insns. */
4219 target_for_arg (type, size, args_addr, offset)
4223 struct args_size offset;
4226 rtx offset_rtx = ARGS_SIZE_RTX (offset);
4228 /* We do not call memory_address if possible,
4229 because we want to address as close to the stack
4230 as possible. For non-variable sized arguments,
4231 this will be stack-pointer relative addressing. */
4232 if (GET_CODE (offset_rtx) == CONST_INT)
4233 target = plus_constant (args_addr, INTVAL (offset_rtx));
4236 /* I have no idea how to guarantee that this
4237 will work in the presence of register parameters. */
4238 target = gen_rtx_PLUS (Pmode, args_addr, offset_rtx);
4239 target = memory_address (QImode, target);
4242 return gen_rtx_MEM (BLKmode, target);
4246 /* Store a single argument for a function call
4247 into the register or memory area where it must be passed.
4248 *ARG describes the argument value and where to pass it.
4250 ARGBLOCK is the address of the stack-block for all the arguments,
4251 or 0 on a machine where arguments are pushed individually.
4253 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4254 so must be careful about how the stack is used.
4256 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4257 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4258 that we need not worry about saving and restoring the stack.
4260 FNDECL is the declaration of the function we are calling.
4262 Return non-zero if this arg should cause sibcall failure,
4266 store_one_arg (arg, argblock, flags, variable_size, reg_parm_stack_space)
4267 struct arg_data *arg;
4270 int variable_size ATTRIBUTE_UNUSED;
4271 int reg_parm_stack_space;
4273 register tree pval = arg->tree_value;
4277 int i, lower_bound = 0, upper_bound = 0;
4278 int sibcall_failure = 0;
4280 if (TREE_CODE (pval) == ERROR_MARK)
4283 /* Push a new temporary level for any temporaries we make for
4287 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4289 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4290 save any previous data at that location. */
4291 if (argblock && ! variable_size && arg->stack)
4293 #ifdef ARGS_GROW_DOWNWARD
4294 /* stack_slot is negative, but we want to index stack_usage_map
4295 with positive values. */
4296 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4297 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4301 lower_bound = upper_bound - arg->size.constant;
4303 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4304 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4308 upper_bound = lower_bound + arg->size.constant;
4311 for (i = lower_bound; i < upper_bound; i++)
4312 if (stack_usage_map[i]
4313 /* Don't store things in the fixed argument area at this point;
4314 it has already been saved. */
4315 && i > reg_parm_stack_space)
4318 if (i != upper_bound)
4320 /* We need to make a save area. See what mode we can make it. */
4321 enum machine_mode save_mode
4322 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
4324 = gen_rtx_MEM (save_mode,
4325 memory_address (save_mode,
4326 XEXP (arg->stack_slot, 0)));
4328 if (save_mode == BLKmode)
4330 arg->save_area = assign_stack_temp (BLKmode,
4331 arg->size.constant, 0);
4332 MEM_SET_IN_STRUCT_P (arg->save_area,
4333 AGGREGATE_TYPE_P (TREE_TYPE
4334 (arg->tree_value)));
4335 preserve_temp_slots (arg->save_area);
4336 emit_block_move (validize_mem (arg->save_area), stack_area,
4337 GEN_INT (arg->size.constant),
4342 arg->save_area = gen_reg_rtx (save_mode);
4343 emit_move_insn (arg->save_area, stack_area);
4347 /* Now that we have saved any slots that will be overwritten by this
4348 store, mark all slots this store will use. We must do this before
4349 we actually expand the argument since the expansion itself may
4350 trigger library calls which might need to use the same stack slot. */
4351 if (argblock && ! variable_size && arg->stack)
4352 for (i = lower_bound; i < upper_bound; i++)
4353 stack_usage_map[i] = 1;
4356 /* If this isn't going to be placed on both the stack and in registers,
4357 set up the register and number of words. */
4358 if (! arg->pass_on_stack)
4359 reg = arg->reg, partial = arg->partial;
4361 if (reg != 0 && partial == 0)
4362 /* Being passed entirely in a register. We shouldn't be called in
4366 /* If this arg needs special alignment, don't load the registers
4368 if (arg->n_aligned_regs != 0)
4371 /* If this is being passed partially in a register, we can't evaluate
4372 it directly into its stack slot. Otherwise, we can. */
4373 if (arg->value == 0)
4375 /* stack_arg_under_construction is nonzero if a function argument is
4376 being evaluated directly into the outgoing argument list and
4377 expand_call must take special action to preserve the argument list
4378 if it is called recursively.
4380 For scalar function arguments stack_usage_map is sufficient to
4381 determine which stack slots must be saved and restored. Scalar
4382 arguments in general have pass_on_stack == 0.
4384 If this argument is initialized by a function which takes the
4385 address of the argument (a C++ constructor or a C function
4386 returning a BLKmode structure), then stack_usage_map is
4387 insufficient and expand_call must push the stack around the
4388 function call. Such arguments have pass_on_stack == 1.
4390 Note that it is always safe to set stack_arg_under_construction,
4391 but this generates suboptimal code if set when not needed. */
4393 if (arg->pass_on_stack)
4394 stack_arg_under_construction++;
4396 arg->value = expand_expr (pval,
4398 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4399 ? NULL_RTX : arg->stack,
4402 /* If we are promoting object (or for any other reason) the mode
4403 doesn't agree, convert the mode. */
4405 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4406 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4407 arg->value, arg->unsignedp);
4409 if (arg->pass_on_stack)
4410 stack_arg_under_construction--;
4413 /* Don't allow anything left on stack from computation
4414 of argument to alloca. */
4415 if (flags & ECF_MAY_BE_ALLOCA)
4416 do_pending_stack_adjust ();
4418 if (arg->value == arg->stack)
4420 /* If the value is already in the stack slot, we are done. */
4421 if (current_function_check_memory_usage && GET_CODE (arg->stack) == MEM)
4423 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4424 XEXP (arg->stack, 0), Pmode,
4425 ARGS_SIZE_RTX (arg->size),
4426 TYPE_MODE (sizetype),
4427 GEN_INT (MEMORY_USE_RW),
4428 TYPE_MODE (integer_type_node));
4431 else if (arg->mode != BLKmode)
4435 /* Argument is a scalar, not entirely passed in registers.
4436 (If part is passed in registers, arg->partial says how much
4437 and emit_push_insn will take care of putting it there.)
4439 Push it, and if its size is less than the
4440 amount of space allocated to it,
4441 also bump stack pointer by the additional space.
4442 Note that in C the default argument promotions
4443 will prevent such mismatches. */
4445 size = GET_MODE_SIZE (arg->mode);
4446 /* Compute how much space the push instruction will push.
4447 On many machines, pushing a byte will advance the stack
4448 pointer by a halfword. */
4449 #ifdef PUSH_ROUNDING
4450 size = PUSH_ROUNDING (size);
4454 /* Compute how much space the argument should get:
4455 round up to a multiple of the alignment for arguments. */
4456 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4457 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4458 / (PARM_BOUNDARY / BITS_PER_UNIT))
4459 * (PARM_BOUNDARY / BITS_PER_UNIT));
4461 /* This isn't already where we want it on the stack, so put it there.
4462 This can either be done with push or copy insns. */
4463 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX, 0,
4464 partial, reg, used - size, argblock,
4465 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4466 ARGS_SIZE_RTX (arg->alignment_pad));
4470 /* BLKmode, at least partly to be pushed. */
4472 register int excess;
4475 /* Pushing a nonscalar.
4476 If part is passed in registers, PARTIAL says how much
4477 and emit_push_insn will take care of putting it there. */
4479 /* Round its size up to a multiple
4480 of the allocation unit for arguments. */
4482 if (arg->size.var != 0)
4485 size_rtx = ARGS_SIZE_RTX (arg->size);
4489 /* PUSH_ROUNDING has no effect on us, because
4490 emit_push_insn for BLKmode is careful to avoid it. */
4491 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4492 + partial * UNITS_PER_WORD);
4493 size_rtx = expr_size (pval);
4496 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4498 /* emit_push_insn might not work properly if arg->value and
4499 argblock + arg->offset areas overlap. */
4503 if (XEXP (x, 0) == current_function_internal_arg_pointer
4504 || (GET_CODE (XEXP (x, 0)) == PLUS
4505 && XEXP (XEXP (x, 0), 0) ==
4506 current_function_internal_arg_pointer
4507 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4509 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4510 i = INTVAL (XEXP (XEXP (x, 0), 1));
4512 /* expand_call should ensure this */
4513 if (arg->offset.var || GET_CODE (size_rtx) != CONST_INT)
4516 if (arg->offset.constant > i)
4518 if (arg->offset.constant < i + INTVAL (size_rtx))
4519 sibcall_failure = 1;
4521 else if (arg->offset.constant < i)
4523 if (i < arg->offset.constant + INTVAL (size_rtx))
4524 sibcall_failure = 1;
4529 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4530 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg, excess,
4531 argblock, ARGS_SIZE_RTX (arg->offset),
4532 reg_parm_stack_space,
4533 ARGS_SIZE_RTX (arg->alignment_pad));
4536 /* Unless this is a partially-in-register argument, the argument is now
4539 ??? Note that this can change arg->value from arg->stack to
4540 arg->stack_slot and it matters when they are not the same.
4541 It isn't totally clear that this is correct in all cases. */
4543 arg->value = arg->stack_slot;
4545 /* Once we have pushed something, pops can't safely
4546 be deferred during the rest of the arguments. */
4549 /* ANSI doesn't require a sequence point here,
4550 but PCC has one, so this will avoid some problems. */
4553 /* Free any temporary slots made in processing this argument. Show
4554 that we might have taken the address of something and pushed that
4556 preserve_temp_slots (NULL_RTX);
4560 return sibcall_failure;