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,
226 static int special_function_p PARAMS ((tree, int));
227 static int flags_from_decl_or_type PARAMS ((tree));
228 static rtx try_to_integrate PARAMS ((tree, tree, rtx,
230 static int check_sibcall_argument_overlap_1 PARAMS ((rtx));
231 static int check_sibcall_argument_overlap PARAMS ((rtx, struct arg_data *));
233 static int combine_pending_stack_adjustment_and_call
234 PARAMS ((int, struct args_size *, int));
236 #ifdef REG_PARM_STACK_SPACE
237 static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
238 static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
241 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
244 If WHICH is 0, return 1 if EXP contains a call to any function.
245 Actually, we only need return 1 if evaluating EXP would require pushing
246 arguments on the stack, but that is too difficult to compute, so we just
247 assume any function call might require the stack. */
249 static tree calls_function_save_exprs;
252 calls_function (exp, which)
258 calls_function_save_exprs = 0;
259 val = calls_function_1 (exp, which);
260 calls_function_save_exprs = 0;
264 /* Recursive function to do the work of above function. */
267 calls_function_1 (exp, which)
272 enum tree_code code = TREE_CODE (exp);
273 int class = TREE_CODE_CLASS (code);
274 int length = first_rtl_op (code);
276 /* If this code is language-specific, we don't know what it will do. */
277 if ((int) code >= NUM_TREE_CODES)
285 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
287 && (TYPE_RETURNS_STACK_DEPRESSED
288 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))))
290 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
291 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
293 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
295 & ECF_MAY_BE_ALLOCA))
301 if (SAVE_EXPR_RTL (exp) != 0)
303 if (value_member (exp, calls_function_save_exprs))
305 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
306 calls_function_save_exprs);
307 return (TREE_OPERAND (exp, 0) != 0
308 && calls_function_1 (TREE_OPERAND (exp, 0), which));
313 register tree subblock;
315 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
316 if (DECL_INITIAL (local) != 0
317 && calls_function_1 (DECL_INITIAL (local), which))
320 for (subblock = BLOCK_SUBBLOCKS (exp);
322 subblock = TREE_CHAIN (subblock))
323 if (calls_function_1 (subblock, which))
329 for (; exp != 0; exp = TREE_CHAIN (exp))
330 if (calls_function_1 (TREE_VALUE (exp), which))
338 /* Only expressions, references, and blocks can contain calls. */
339 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
342 for (i = 0; i < length; i++)
343 if (TREE_OPERAND (exp, i) != 0
344 && calls_function_1 (TREE_OPERAND (exp, i), which))
350 /* Force FUNEXP into a form suitable for the address of a CALL,
351 and return that as an rtx. Also load the static chain register
352 if FNDECL is a nested function.
354 CALL_FUSAGE points to a variable holding the prospective
355 CALL_INSN_FUNCTION_USAGE information. */
358 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen)
364 rtx static_chain_value = 0;
366 funexp = protect_from_queue (funexp, 0);
369 /* Get possible static chain value for nested function in C. */
370 static_chain_value = lookup_static_chain (fndecl);
372 /* Make a valid memory address and copy constants thru pseudo-regs,
373 but not for a constant address if -fno-function-cse. */
374 if (GET_CODE (funexp) != SYMBOL_REF)
375 /* If we are using registers for parameters, force the
376 function address into a register now. */
377 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
378 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
379 : memory_address (FUNCTION_MODE, funexp));
382 #ifndef NO_FUNCTION_CSE
383 if (optimize && ! flag_no_function_cse)
384 #ifdef NO_RECURSIVE_FUNCTION_CSE
385 if (fndecl != current_function_decl)
387 funexp = force_reg (Pmode, funexp);
391 if (static_chain_value != 0)
393 emit_move_insn (static_chain_rtx, static_chain_value);
395 if (GET_CODE (static_chain_rtx) == REG)
396 use_reg (call_fusage, static_chain_rtx);
402 /* Generate instructions to call function FUNEXP,
403 and optionally pop the results.
404 The CALL_INSN is the first insn generated.
406 FNDECL is the declaration node of the function. This is given to the
407 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
409 FUNTYPE is the data type of the function. This is given to the macro
410 RETURN_POPS_ARGS to determine whether this function pops its own args.
411 We used to allow an identifier for library functions, but that doesn't
412 work when the return type is an aggregate type and the calling convention
413 says that the pointer to this aggregate is to be popped by the callee.
415 STACK_SIZE is the number of bytes of arguments on the stack,
416 ROUNDED_STACK_SIZE is that number rounded up to
417 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
418 both to put into the call insn and to generate explicit popping
421 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
422 It is zero if this call doesn't want a structure value.
424 NEXT_ARG_REG is the rtx that results from executing
425 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
426 just after all the args have had their registers assigned.
427 This could be whatever you like, but normally it is the first
428 arg-register beyond those used for args in this call,
429 or 0 if all the arg-registers are used in this call.
430 It is passed on to `gen_call' so you can put this info in the call insn.
432 VALREG is a hard register in which a value is returned,
433 or 0 if the call does not return a value.
435 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
436 the args to this call were processed.
437 We restore `inhibit_defer_pop' to that value.
439 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
440 denote registers used by the called function. */
443 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
444 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
445 call_fusage, ecf_flags)
447 tree fndecl ATTRIBUTE_UNUSED;
448 tree funtype ATTRIBUTE_UNUSED;
449 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
450 HOST_WIDE_INT rounded_stack_size;
451 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
454 int old_inhibit_defer_pop;
458 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
460 int already_popped = 0;
461 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
462 #if defined (HAVE_call) && defined (HAVE_call_value)
463 rtx struct_value_size_rtx;
464 struct_value_size_rtx = GEN_INT (struct_value_size);
467 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
468 and we don't want to load it into a register as an optimization,
469 because prepare_call_address already did it if it should be done. */
470 if (GET_CODE (funexp) != SYMBOL_REF)
471 funexp = memory_address (FUNCTION_MODE, funexp);
473 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
474 if ((ecf_flags & ECF_SIBCALL)
475 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
476 && (n_popped > 0 || stack_size == 0))
478 rtx n_pop = GEN_INT (n_popped));
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, LCT_CONST_MAKE_BLOCK,
1682 VOIDmode, 1, funaddr, Pmode);
1689 /* Do the register loads required for any wholly-register parms or any
1690 parms which are passed both on the stack and in a register. Their
1691 expressions were already evaluated.
1693 Mark all register-parms as living through the call, putting these USE
1694 insns in the CALL_INSN_FUNCTION_USAGE field. */
1697 load_register_parameters (args, num_actuals, call_fusage, flags)
1698 struct arg_data *args;
1705 #ifdef LOAD_ARGS_REVERSED
1706 for (i = num_actuals - 1; i >= 0; i--)
1708 for (i = 0; i < num_actuals; i++)
1711 rtx reg = ((flags & ECF_SIBCALL)
1712 ? args[i].tail_call_reg : args[i].reg);
1713 int partial = args[i].partial;
1718 /* Set to non-negative if must move a word at a time, even if just
1719 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1720 we just use a normal move insn. This value can be zero if the
1721 argument is a zero size structure with no fields. */
1722 nregs = (partial ? partial
1723 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1724 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1725 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1728 /* Handle calls that pass values in multiple non-contiguous
1729 locations. The Irix 6 ABI has examples of this. */
1731 if (GET_CODE (reg) == PARALLEL)
1732 emit_group_load (reg, args[i].value,
1733 int_size_in_bytes (TREE_TYPE (args[i].tree_value)),
1734 TYPE_ALIGN (TREE_TYPE (args[i].tree_value)));
1736 /* If simple case, just do move. If normal partial, store_one_arg
1737 has already loaded the register for us. In all other cases,
1738 load the register(s) from memory. */
1740 else if (nregs == -1)
1741 emit_move_insn (reg, args[i].value);
1743 /* If we have pre-computed the values to put in the registers in
1744 the case of non-aligned structures, copy them in now. */
1746 else if (args[i].n_aligned_regs != 0)
1747 for (j = 0; j < args[i].n_aligned_regs; j++)
1748 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1749 args[i].aligned_regs[j]);
1751 else if (partial == 0 || args[i].pass_on_stack)
1752 move_block_to_reg (REGNO (reg),
1753 validize_mem (args[i].value), nregs,
1756 /* Handle calls that pass values in multiple non-contiguous
1757 locations. The Irix 6 ABI has examples of this. */
1758 if (GET_CODE (reg) == PARALLEL)
1759 use_group_regs (call_fusage, reg);
1760 else if (nregs == -1)
1761 use_reg (call_fusage, reg);
1763 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1768 /* Try to integrate function. See expand_inline_function for documentation
1769 about the parameters. */
1772 try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1778 rtx structure_value_addr;
1783 rtx old_stack_level = 0;
1784 int reg_parm_stack_space = 0;
1786 #ifdef REG_PARM_STACK_SPACE
1787 #ifdef MAYBE_REG_PARM_STACK_SPACE
1788 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1790 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1794 before_call = get_last_insn ();
1796 timevar_push (TV_INTEGRATION);
1798 temp = expand_inline_function (fndecl, actparms, target,
1800 structure_value_addr);
1802 timevar_pop (TV_INTEGRATION);
1804 /* If inlining succeeded, return. */
1805 if (temp != (rtx) (HOST_WIDE_INT) - 1)
1807 if (ACCUMULATE_OUTGOING_ARGS)
1809 /* If the outgoing argument list must be preserved, push
1810 the stack before executing the inlined function if it
1813 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1814 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1817 if (stack_arg_under_construction || i >= 0)
1820 = before_call ? NEXT_INSN (before_call) : get_insns ();
1821 rtx insn = NULL_RTX, seq;
1823 /* Look for a call in the inline function code.
1824 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1825 nonzero then there is a call and it is not necessary
1826 to scan the insns. */
1828 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1829 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1830 if (GET_CODE (insn) == CALL_INSN)
1835 /* Reserve enough stack space so that the largest
1836 argument list of any function call in the inline
1837 function does not overlap the argument list being
1838 evaluated. This is usually an overestimate because
1839 allocate_dynamic_stack_space reserves space for an
1840 outgoing argument list in addition to the requested
1841 space, but there is no way to ask for stack space such
1842 that an argument list of a certain length can be
1845 Add the stack space reserved for register arguments, if
1846 any, in the inline function. What is really needed is the
1847 largest value of reg_parm_stack_space in the inline
1848 function, but that is not available. Using the current
1849 value of reg_parm_stack_space is wrong, but gives
1850 correct results on all supported machines. */
1852 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1853 + reg_parm_stack_space);
1856 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1857 allocate_dynamic_stack_space (GEN_INT (adjust),
1858 NULL_RTX, BITS_PER_UNIT);
1861 emit_insns_before (seq, first_insn);
1862 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1867 /* If the result is equivalent to TARGET, return TARGET to simplify
1868 checks in store_expr. They can be equivalent but not equal in the
1869 case of a function that returns BLKmode. */
1870 if (temp != target && rtx_equal_p (temp, target))
1875 /* If inlining failed, mark FNDECL as needing to be compiled
1876 separately after all. If function was declared inline,
1878 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1879 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1881 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1882 warning ("called from here");
1884 mark_addressable (fndecl);
1885 return (rtx) (HOST_WIDE_INT) - 1;
1888 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1889 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1890 bytes, then we would need to push some additional bytes to pad the
1891 arguments. So, we compute an adjust to the stack pointer for an
1892 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1893 bytes. Then, when the arguments are pushed the stack will be perfectly
1894 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1895 be popped after the call. Returns the adjustment. */
1898 combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1900 preferred_unit_stack_boundary)
1901 int unadjusted_args_size;
1902 struct args_size *args_size;
1903 int preferred_unit_stack_boundary;
1905 /* The number of bytes to pop so that the stack will be
1906 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1907 HOST_WIDE_INT adjustment;
1908 /* The alignment of the stack after the arguments are pushed, if we
1909 just pushed the arguments without adjust the stack here. */
1910 HOST_WIDE_INT unadjusted_alignment;
1912 unadjusted_alignment
1913 = ((stack_pointer_delta + unadjusted_args_size)
1914 % preferred_unit_stack_boundary);
1916 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1917 as possible -- leaving just enough left to cancel out the
1918 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1919 PENDING_STACK_ADJUST is non-negative, and congruent to
1920 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1922 /* Begin by trying to pop all the bytes. */
1923 unadjusted_alignment
1924 = (unadjusted_alignment
1925 - (pending_stack_adjust % preferred_unit_stack_boundary));
1926 adjustment = pending_stack_adjust;
1927 /* Push enough additional bytes that the stack will be aligned
1928 after the arguments are pushed. */
1929 if (preferred_unit_stack_boundary > 1)
1931 if (unadjusted_alignment > 0)
1932 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1934 adjustment += unadjusted_alignment;
1937 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1938 bytes after the call. The right number is the entire
1939 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1940 by the arguments in the first place. */
1942 = pending_stack_adjust - adjustment + unadjusted_args_size;
1947 /* Scan X expression if it does not dereference any argument slots
1948 we already clobbered by tail call arguments (as noted in stored_args_map
1950 Return non-zero if X expression dereferences such argument slots,
1954 check_sibcall_argument_overlap_1 (x)
1965 code = GET_CODE (x);
1969 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1971 else if (GET_CODE (XEXP (x, 0)) == PLUS
1972 && XEXP (XEXP (x, 0), 0) ==
1973 current_function_internal_arg_pointer
1974 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1975 i = INTVAL (XEXP (XEXP (x, 0), 1));
1979 #ifdef ARGS_GROW_DOWNWARD
1980 i = -i - GET_MODE_SIZE (GET_MODE (x));
1983 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
1984 if (i + k < stored_args_map->n_bits
1985 && TEST_BIT (stored_args_map, i + k))
1991 /* Scan all subexpressions. */
1992 fmt = GET_RTX_FORMAT (code);
1993 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1997 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2000 else if (*fmt == 'E')
2002 for (j = 0; j < XVECLEN (x, i); j++)
2003 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2010 /* Scan sequence after INSN if it does not dereference any argument slots
2011 we already clobbered by tail call arguments (as noted in stored_args_map
2012 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2013 Return non-zero if sequence after INSN dereferences such argument slots,
2017 check_sibcall_argument_overlap (insn, arg)
2019 struct arg_data *arg;
2023 if (insn == NULL_RTX)
2024 insn = get_insns ();
2026 insn = NEXT_INSN (insn);
2028 for (; insn; insn = NEXT_INSN (insn))
2030 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2033 #ifdef ARGS_GROW_DOWNWARD
2034 low = -arg->offset.constant - arg->size.constant;
2036 low = arg->offset.constant;
2039 for (high = low + arg->size.constant; low < high; low++)
2040 SET_BIT (stored_args_map, low);
2041 return insn != NULL_RTX;
2044 /* Generate all the code for a function call
2045 and return an rtx for its value.
2046 Store the value in TARGET (specified as an rtx) if convenient.
2047 If the value is stored in TARGET then TARGET is returned.
2048 If IGNORE is nonzero, then we ignore the value of the function call. */
2051 expand_call (exp, target, ignore)
2056 /* Nonzero if we are currently expanding a call. */
2057 static int currently_expanding_call = 0;
2059 /* List of actual parameters. */
2060 tree actparms = TREE_OPERAND (exp, 1);
2061 /* RTX for the function to be called. */
2063 /* Sequence of insns to perform a tail recursive "call". */
2064 rtx tail_recursion_insns = NULL_RTX;
2065 /* Sequence of insns to perform a normal "call". */
2066 rtx normal_call_insns = NULL_RTX;
2067 /* Sequence of insns to perform a tail recursive "call". */
2068 rtx tail_call_insns = NULL_RTX;
2069 /* Data type of the function. */
2071 /* Declaration of the function being called,
2072 or 0 if the function is computed (not known by name). */
2075 int try_tail_call = 1;
2076 int try_tail_recursion = 1;
2079 /* Register in which non-BLKmode value will be returned,
2080 or 0 if no value or if value is BLKmode. */
2082 /* Address where we should return a BLKmode value;
2083 0 if value not BLKmode. */
2084 rtx structure_value_addr = 0;
2085 /* Nonzero if that address is being passed by treating it as
2086 an extra, implicit first parameter. Otherwise,
2087 it is passed by being copied directly into struct_value_rtx. */
2088 int structure_value_addr_parm = 0;
2089 /* Size of aggregate value wanted, or zero if none wanted
2090 or if we are using the non-reentrant PCC calling convention
2091 or expecting the value in registers. */
2092 HOST_WIDE_INT struct_value_size = 0;
2093 /* Nonzero if called function returns an aggregate in memory PCC style,
2094 by returning the address of where to find it. */
2095 int pcc_struct_value = 0;
2097 /* Number of actual parameters in this call, including struct value addr. */
2099 /* Number of named args. Args after this are anonymous ones
2100 and they must all go on the stack. */
2103 /* Vector of information about each argument.
2104 Arguments are numbered in the order they will be pushed,
2105 not the order they are written. */
2106 struct arg_data *args;
2108 /* Total size in bytes of all the stack-parms scanned so far. */
2109 struct args_size args_size;
2110 struct args_size adjusted_args_size;
2111 /* Size of arguments before any adjustments (such as rounding). */
2112 int unadjusted_args_size;
2113 /* Data on reg parms scanned so far. */
2114 CUMULATIVE_ARGS args_so_far;
2115 /* Nonzero if a reg parm has been scanned. */
2117 /* Nonzero if this is an indirect function call. */
2119 /* Nonzero if we must avoid push-insns in the args for this call.
2120 If stack space is allocated for register parameters, but not by the
2121 caller, then it is preallocated in the fixed part of the stack frame.
2122 So the entire argument block must then be preallocated (i.e., we
2123 ignore PUSH_ROUNDING in that case). */
2125 int must_preallocate = !PUSH_ARGS;
2127 /* Size of the stack reserved for parameter registers. */
2128 int reg_parm_stack_space = 0;
2130 /* Address of space preallocated for stack parms
2131 (on machines that lack push insns), or 0 if space not preallocated. */
2134 /* Mask of ECF_ flags. */
2136 /* Nonzero if this is a call to an inline function. */
2137 int is_integrable = 0;
2138 #ifdef REG_PARM_STACK_SPACE
2139 /* Define the boundary of the register parm stack space that needs to be
2141 int low_to_save = -1, high_to_save;
2142 rtx save_area = 0; /* Place that it is saved */
2145 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2146 char *initial_stack_usage_map = stack_usage_map;
2147 int old_stack_arg_under_construction = 0;
2149 rtx old_stack_level = 0;
2150 int old_pending_adj = 0;
2151 int old_inhibit_defer_pop = inhibit_defer_pop;
2152 int old_stack_allocated;
2154 register tree p = TREE_OPERAND (exp, 0);
2156 /* The alignment of the stack, in bits. */
2157 HOST_WIDE_INT preferred_stack_boundary;
2158 /* The alignment of the stack, in bytes. */
2159 HOST_WIDE_INT preferred_unit_stack_boundary;
2161 /* The value of the function call can be put in a hard register. But
2162 if -fcheck-memory-usage, code which invokes functions (and thus
2163 damages some hard registers) can be inserted before using the value.
2164 So, target is always a pseudo-register in that case. */
2165 if (current_function_check_memory_usage)
2168 /* See if this is "nothrow" function call. */
2169 if (TREE_NOTHROW (exp))
2170 flags |= ECF_NOTHROW;
2172 /* See if we can find a DECL-node for the actual function.
2173 As a result, decide whether this is a call to an integrable function. */
2175 fndecl = get_callee_fndecl (exp);
2179 && fndecl != current_function_decl
2180 && DECL_INLINE (fndecl)
2181 && DECL_SAVED_INSNS (fndecl)
2182 && DECL_SAVED_INSNS (fndecl)->inlinable)
2184 else if (! TREE_ADDRESSABLE (fndecl))
2186 /* In case this function later becomes inlinable,
2187 record that there was already a non-inline call to it.
2189 Use abstraction instead of setting TREE_ADDRESSABLE
2191 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2194 warning_with_decl (fndecl, "can't inline call to `%s'");
2195 warning ("called from here");
2197 mark_addressable (fndecl);
2200 flags |= flags_from_decl_or_type (fndecl);
2203 /* If we don't have specific function to call, see if we have a
2204 attributes set in the type. */
2206 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2208 /* Mark if the function returns with the stack pointer depressed. */
2209 if (TREE_CODE (TREE_TYPE (TREE_TYPE (p))) == FUNCTION_TYPE
2210 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (TREE_TYPE (p))))
2212 flags |= ECF_SP_DEPRESSED;
2213 flags &= ~(ECF_PURE | ECF_CONST);
2216 #ifdef REG_PARM_STACK_SPACE
2217 #ifdef MAYBE_REG_PARM_STACK_SPACE
2218 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2220 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2224 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2225 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2226 must_preallocate = 1;
2229 /* Warn if this value is an aggregate type,
2230 regardless of which calling convention we are using for it. */
2231 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2232 warning ("function call has aggregate value");
2234 /* Set up a place to return a structure. */
2236 /* Cater to broken compilers. */
2237 if (aggregate_value_p (exp))
2239 /* This call returns a big structure. */
2240 flags &= ~(ECF_CONST | ECF_PURE);
2242 #ifdef PCC_STATIC_STRUCT_RETURN
2244 pcc_struct_value = 1;
2245 /* Easier than making that case work right. */
2248 /* In case this is a static function, note that it has been
2250 if (! TREE_ADDRESSABLE (fndecl))
2251 mark_addressable (fndecl);
2255 #else /* not PCC_STATIC_STRUCT_RETURN */
2257 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2259 if (target && GET_CODE (target) == MEM)
2260 structure_value_addr = XEXP (target, 0);
2265 /* For variable-sized objects, we must be called with a target
2266 specified. If we were to allocate space on the stack here,
2267 we would have no way of knowing when to free it. */
2269 if (struct_value_size < 0)
2272 d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2273 mark_temp_addr_taken (d);
2274 structure_value_addr = XEXP (d, 0);
2278 #endif /* not PCC_STATIC_STRUCT_RETURN */
2281 /* If called function is inline, try to integrate it. */
2285 rtx temp = try_to_integrate (fndecl, actparms, target,
2286 ignore, TREE_TYPE (exp),
2287 structure_value_addr);
2288 if (temp != (rtx) (HOST_WIDE_INT) - 1)
2292 /* Figure out the amount to which the stack should be aligned. */
2293 #ifdef PREFERRED_STACK_BOUNDARY
2294 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2296 preferred_stack_boundary = STACK_BOUNDARY;
2299 /* Operand 0 is a pointer-to-function; get the type of the function. */
2300 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
2301 if (! POINTER_TYPE_P (funtype))
2303 funtype = TREE_TYPE (funtype);
2305 /* See if this is a call to a function that can return more than once
2306 or a call to longjmp or malloc. */
2307 flags |= special_function_p (fndecl, flags);
2309 if (flags & ECF_MAY_BE_ALLOCA)
2310 current_function_calls_alloca = 1;
2312 /* If struct_value_rtx is 0, it means pass the address
2313 as if it were an extra parameter. */
2314 if (structure_value_addr && struct_value_rtx == 0)
2316 /* If structure_value_addr is a REG other than
2317 virtual_outgoing_args_rtx, we can use always use it. If it
2318 is not a REG, we must always copy it into a register.
2319 If it is virtual_outgoing_args_rtx, we must copy it to another
2320 register in some cases. */
2321 rtx temp = (GET_CODE (structure_value_addr) != REG
2322 || (ACCUMULATE_OUTGOING_ARGS
2323 && stack_arg_under_construction
2324 && structure_value_addr == virtual_outgoing_args_rtx)
2325 ? copy_addr_to_reg (structure_value_addr)
2326 : structure_value_addr);
2329 = tree_cons (error_mark_node,
2330 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2333 structure_value_addr_parm = 1;
2336 /* Count the arguments and set NUM_ACTUALS. */
2337 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2340 /* Compute number of named args.
2341 Normally, don't include the last named arg if anonymous args follow.
2342 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2343 (If no anonymous args follow, the result of list_length is actually
2344 one too large. This is harmless.)
2346 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2347 zero, this machine will be able to place unnamed args that were
2348 passed in registers into the stack. So treat all args as named.
2349 This allows the insns emitting for a specific argument list to be
2350 independent of the function declaration.
2352 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2353 reliable way to pass unnamed args in registers, so we must force
2354 them into memory. */
2356 if ((STRICT_ARGUMENT_NAMING
2357 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2358 && TYPE_ARG_TYPES (funtype) != 0)
2360 = (list_length (TYPE_ARG_TYPES (funtype))
2361 /* Don't include the last named arg. */
2362 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2363 /* Count the struct value address, if it is passed as a parm. */
2364 + structure_value_addr_parm);
2366 /* If we know nothing, treat all args as named. */
2367 n_named_args = num_actuals;
2369 /* Start updating where the next arg would go.
2371 On some machines (such as the PA) indirect calls have a different
2372 calling convention than normal calls. The last argument in
2373 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2375 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
2377 /* Make a vector to hold all the information about each arg. */
2378 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
2379 memset ((char *) args, 0, num_actuals * sizeof (struct arg_data));
2381 /* Build up entries inthe ARGS array, compute the size of the arguments
2382 into ARGS_SIZE, etc. */
2383 initialize_argument_information (num_actuals, args, &args_size,
2384 n_named_args, actparms, fndecl,
2385 &args_so_far, reg_parm_stack_space,
2386 &old_stack_level, &old_pending_adj,
2387 &must_preallocate, &flags);
2391 /* If this function requires a variable-sized argument list, don't
2392 try to make a cse'able block for this call. We may be able to
2393 do this eventually, but it is too complicated to keep track of
2394 what insns go in the cse'able block and which don't. */
2396 flags &= ~(ECF_CONST | ECF_PURE);
2397 must_preallocate = 1;
2400 /* Now make final decision about preallocating stack space. */
2401 must_preallocate = finalize_must_preallocate (must_preallocate,
2405 /* If the structure value address will reference the stack pointer, we
2406 must stabilize it. We don't need to do this if we know that we are
2407 not going to adjust the stack pointer in processing this call. */
2409 if (structure_value_addr
2410 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2411 || reg_mentioned_p (virtual_outgoing_args_rtx,
2412 structure_value_addr))
2414 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2415 structure_value_addr = copy_to_reg (structure_value_addr);
2417 /* Tail calls can make things harder to debug, and we're traditionally
2418 pushed these optimizations into -O2. Don't try if we're already
2419 expanding a call, as that means we're an argument. Don't try if
2420 there's cleanups, as we know there's code to follow the call.
2422 If rtx_equal_function_value_matters is false, that means we've
2423 finished with regular parsing. Which means that some of the
2424 machinery we use to generate tail-calls is no longer in place.
2425 This is most often true of sjlj-exceptions, which we couldn't
2426 tail-call to anyway. */
2428 if (currently_expanding_call++ != 0
2429 || !flag_optimize_sibling_calls
2430 || !rtx_equal_function_value_matters
2431 || any_pending_cleanups (1)
2433 try_tail_call = try_tail_recursion = 0;
2435 /* Tail recursion fails, when we are not dealing with recursive calls. */
2436 if (!try_tail_recursion
2437 || TREE_CODE (TREE_OPERAND (exp, 0)) != ADDR_EXPR
2438 || TREE_OPERAND (TREE_OPERAND (exp, 0), 0) != current_function_decl)
2439 try_tail_recursion = 0;
2441 /* Rest of purposes for tail call optimizations to fail. */
2443 #ifdef HAVE_sibcall_epilogue
2444 !HAVE_sibcall_epilogue
2449 /* Doing sibling call optimization needs some work, since
2450 structure_value_addr can be allocated on the stack.
2451 It does not seem worth the effort since few optimizable
2452 sibling calls will return a structure. */
2453 || structure_value_addr != NULL_RTX
2454 /* If the register holding the address is a callee saved
2455 register, then we lose. We have no way to prevent that,
2456 so we only allow calls to named functions. */
2457 /* ??? This could be done by having the insn constraints
2458 use a register class that is all call-clobbered. Any
2459 reload insns generated to fix things up would appear
2460 before the sibcall_epilogue. */
2461 || fndecl == NULL_TREE
2462 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP))
2463 || TREE_THIS_VOLATILE (fndecl)
2464 || !FUNCTION_OK_FOR_SIBCALL (fndecl)
2465 /* If this function requires more stack slots than the current
2466 function, we cannot change it into a sibling call. */
2467 || args_size.constant > current_function_args_size
2468 /* If the callee pops its own arguments, then it must pop exactly
2469 the same number of arguments as the current function. */
2470 || RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2471 != RETURN_POPS_ARGS (current_function_decl,
2472 TREE_TYPE (current_function_decl),
2473 current_function_args_size))
2476 if (try_tail_call || try_tail_recursion)
2479 actparms = NULL_TREE;
2480 /* Ok, we're going to give the tail call the old college try.
2481 This means we're going to evaluate the function arguments
2482 up to three times. There are two degrees of badness we can
2483 encounter, those that can be unsaved and those that can't.
2484 (See unsafe_for_reeval commentary for details.)
2486 Generate a new argument list. Pass safe arguments through
2487 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2488 For hard badness, evaluate them now and put their resulting
2489 rtx in a temporary VAR_DECL.
2491 initialize_argument_information has ordered the array for the
2492 order to be pushed, and we must remember this when reconstructing
2493 the original argument orde. */
2495 if (PUSH_ARGS_REVERSED)
2504 i = num_actuals - 1;
2508 for (; i != end; i += inc)
2510 switch (unsafe_for_reeval (args[i].tree_value))
2515 case 1: /* Mildly unsafe. */
2516 args[i].tree_value = unsave_expr (args[i].tree_value);
2519 case 2: /* Wildly unsafe. */
2521 tree var = build_decl (VAR_DECL, NULL_TREE,
2522 TREE_TYPE (args[i].tree_value));
2523 DECL_RTL (var) = expand_expr (args[i].tree_value, NULL_RTX,
2524 VOIDmode, EXPAND_NORMAL);
2525 args[i].tree_value = var;
2532 /* We need to build actparms for optimize_tail_recursion. We can
2533 safely trash away TREE_PURPOSE, since it is unused by this
2535 if (try_tail_recursion)
2536 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2538 /* Expanding one of those dangerous arguments could have added
2539 cleanups, but otherwise give it a whirl. */
2540 if (any_pending_cleanups (1))
2541 try_tail_call = try_tail_recursion = 0;
2544 /* Generate a tail recursion sequence when calling ourselves. */
2546 if (try_tail_recursion)
2548 /* We want to emit any pending stack adjustments before the tail
2549 recursion "call". That way we know any adjustment after the tail
2550 recursion call can be ignored if we indeed use the tail recursion
2552 int save_pending_stack_adjust = pending_stack_adjust;
2553 int save_stack_pointer_delta = stack_pointer_delta;
2555 /* Use a new sequence to hold any RTL we generate. We do not even
2556 know if we will use this RTL yet. The final decision can not be
2557 made until after RTL generation for the entire function is
2560 /* If expanding any of the arguments creates cleanups, we can't
2561 do a tailcall. So, we'll need to pop the pending cleanups
2562 list. If, however, all goes well, and there are no cleanups
2563 then the call to expand_start_target_temps will have no
2565 expand_start_target_temps ();
2566 if (optimize_tail_recursion (actparms, get_last_insn ()))
2568 if (any_pending_cleanups (1))
2569 try_tail_call = try_tail_recursion = 0;
2571 tail_recursion_insns = get_insns ();
2573 expand_end_target_temps ();
2576 /* Restore the original pending stack adjustment for the sibling and
2577 normal call cases below. */
2578 pending_stack_adjust = save_pending_stack_adjust;
2579 stack_pointer_delta = save_stack_pointer_delta;
2582 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2584 /* A fork duplicates the profile information, and an exec discards
2585 it. We can't rely on fork/exec to be paired. So write out the
2586 profile information we have gathered so far, and clear it. */
2587 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2588 is subject to race conditions, just as with multithreaded
2591 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__bb_fork_func"), 0,
2595 /* Ensure current function's preferred stack boundary is at least
2596 what we need. We don't have to increase alignment for recursive
2598 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2599 && fndecl != current_function_decl)
2600 cfun->preferred_stack_boundary = preferred_stack_boundary;
2602 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2604 function_call_count++;
2606 /* We want to make two insn chains; one for a sibling call, the other
2607 for a normal call. We will select one of the two chains after
2608 initial RTL generation is complete. */
2609 for (pass = 0; pass < 2; pass++)
2611 int sibcall_failure = 0;
2612 /* We want to emit ay pending stack adjustments before the tail
2613 recursion "call". That way we know any adjustment after the tail
2614 recursion call can be ignored if we indeed use the tail recursion
2616 int save_pending_stack_adjust = 0;
2617 int save_stack_pointer_delta = 0;
2619 rtx before_call, next_arg_reg;
2623 if (! try_tail_call)
2626 /* Emit any queued insns now; otherwise they would end up in
2627 only one of the alternates. */
2630 /* State variables we need to save and restore between
2632 save_pending_stack_adjust = pending_stack_adjust;
2633 save_stack_pointer_delta = stack_pointer_delta;
2636 flags &= ~ECF_SIBCALL;
2638 flags |= ECF_SIBCALL;
2640 /* Other state variables that we must reinitialize each time
2641 through the loop (that are not initialized by the loop itself). */
2645 /* Start a new sequence for the normal call case.
2647 From this point on, if the sibling call fails, we want to set
2648 sibcall_failure instead of continuing the loop. */
2653 /* We know at this point that there are not currently any
2654 pending cleanups. If, however, in the process of evaluating
2655 the arguments we were to create some, we'll need to be
2656 able to get rid of them. */
2657 expand_start_target_temps ();
2660 /* When calling a const function, we must pop the stack args right away,
2661 so that the pop is deleted or moved with the call. */
2662 if (flags & (ECF_CONST | ECF_PURE))
2665 /* Don't let pending stack adjusts add up to too much.
2666 Also, do all pending adjustments now if there is any chance
2667 this might be a call to alloca or if we are expanding a sibling
2669 if (pending_stack_adjust >= 32
2670 || (pending_stack_adjust > 0 && (flags & ECF_MAY_BE_ALLOCA))
2672 do_pending_stack_adjust ();
2674 /* Push the temporary stack slot level so that we can free any
2675 temporaries we make. */
2678 #ifdef FINAL_REG_PARM_STACK_SPACE
2679 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2682 /* Precompute any arguments as needed. */
2684 precompute_arguments (flags, num_actuals, args);
2686 /* Now we are about to start emitting insns that can be deleted
2687 if a libcall is deleted. */
2688 if (flags & (ECF_CONST | ECF_PURE | ECF_MALLOC))
2691 adjusted_args_size = args_size;
2692 /* Compute the actual size of the argument block required. The variable
2693 and constant sizes must be combined, the size may have to be rounded,
2694 and there may be a minimum required size. When generating a sibcall
2695 pattern, do not round up, since we'll be re-using whatever space our
2697 unadjusted_args_size
2698 = compute_argument_block_size (reg_parm_stack_space,
2699 &adjusted_args_size,
2701 : preferred_stack_boundary));
2703 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2705 /* The argument block when performing a sibling call is the
2706 incoming argument block. */
2709 argblock = virtual_incoming_args_rtx;
2710 stored_args_map = sbitmap_alloc (args_size.constant);
2711 sbitmap_zero (stored_args_map);
2714 /* If we have no actual push instructions, or shouldn't use them,
2715 make space for all args right now. */
2716 else if (adjusted_args_size.var != 0)
2718 if (old_stack_level == 0)
2720 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2721 old_pending_adj = pending_stack_adjust;
2722 pending_stack_adjust = 0;
2723 /* stack_arg_under_construction says whether a stack arg is
2724 being constructed at the old stack level. Pushing the stack
2725 gets a clean outgoing argument block. */
2726 old_stack_arg_under_construction = stack_arg_under_construction;
2727 stack_arg_under_construction = 0;
2729 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2733 /* Note that we must go through the motions of allocating an argument
2734 block even if the size is zero because we may be storing args
2735 in the area reserved for register arguments, which may be part of
2738 int needed = adjusted_args_size.constant;
2740 /* Store the maximum argument space used. It will be pushed by
2741 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2744 if (needed > current_function_outgoing_args_size)
2745 current_function_outgoing_args_size = needed;
2747 if (must_preallocate)
2749 if (ACCUMULATE_OUTGOING_ARGS)
2751 /* Since the stack pointer will never be pushed, it is
2752 possible for the evaluation of a parm to clobber
2753 something we have already written to the stack.
2754 Since most function calls on RISC machines do not use
2755 the stack, this is uncommon, but must work correctly.
2757 Therefore, we save any area of the stack that was already
2758 written and that we are using. Here we set up to do this
2759 by making a new stack usage map from the old one. The
2760 actual save will be done by store_one_arg.
2762 Another approach might be to try to reorder the argument
2763 evaluations to avoid this conflicting stack usage. */
2765 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2766 /* Since we will be writing into the entire argument area,
2767 the map must be allocated for its entire size, not just
2768 the part that is the responsibility of the caller. */
2769 needed += reg_parm_stack_space;
2772 #ifdef ARGS_GROW_DOWNWARD
2773 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2776 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2780 = (char *) alloca (highest_outgoing_arg_in_use);
2782 if (initial_highest_arg_in_use)
2783 memcpy (stack_usage_map, initial_stack_usage_map,
2784 initial_highest_arg_in_use);
2786 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2787 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2788 (highest_outgoing_arg_in_use
2789 - initial_highest_arg_in_use));
2792 /* The address of the outgoing argument list must not be
2793 copied to a register here, because argblock would be left
2794 pointing to the wrong place after the call to
2795 allocate_dynamic_stack_space below. */
2797 argblock = virtual_outgoing_args_rtx;
2801 if (inhibit_defer_pop == 0)
2803 /* Try to reuse some or all of the pending_stack_adjust
2804 to get this space. */
2806 = (combine_pending_stack_adjustment_and_call
2807 (unadjusted_args_size,
2808 &adjusted_args_size,
2809 preferred_unit_stack_boundary));
2811 /* combine_pending_stack_adjustment_and_call computes
2812 an adjustment before the arguments are allocated.
2813 Account for them and see whether or not the stack
2814 needs to go up or down. */
2815 needed = unadjusted_args_size - needed;
2819 /* We're releasing stack space. */
2820 /* ??? We can avoid any adjustment at all if we're
2821 already aligned. FIXME. */
2822 pending_stack_adjust = -needed;
2823 do_pending_stack_adjust ();
2827 /* We need to allocate space. We'll do that in
2828 push_block below. */
2829 pending_stack_adjust = 0;
2832 /* Special case this because overhead of `push_block' in
2833 this case is non-trivial. */
2835 argblock = virtual_outgoing_args_rtx;
2837 argblock = push_block (GEN_INT (needed), 0, 0);
2839 /* We only really need to call `copy_to_reg' in the case
2840 where push insns are going to be used to pass ARGBLOCK
2841 to a function call in ARGS. In that case, the stack
2842 pointer changes value from the allocation point to the
2843 call point, and hence the value of
2844 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2845 as well always do it. */
2846 argblock = copy_to_reg (argblock);
2848 /* The save/restore code in store_one_arg handles all
2849 cases except one: a constructor call (including a C
2850 function returning a BLKmode struct) to initialize
2852 if (stack_arg_under_construction)
2854 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2855 rtx push_size = GEN_INT (reg_parm_stack_space
2856 + adjusted_args_size.constant);
2858 rtx push_size = GEN_INT (adjusted_args_size.constant);
2860 if (old_stack_level == 0)
2862 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2864 old_pending_adj = pending_stack_adjust;
2865 pending_stack_adjust = 0;
2866 /* stack_arg_under_construction says whether a stack
2867 arg is being constructed at the old stack level.
2868 Pushing the stack gets a clean outgoing argument
2870 old_stack_arg_under_construction
2871 = stack_arg_under_construction;
2872 stack_arg_under_construction = 0;
2873 /* Make a new map for the new argument list. */
2874 stack_usage_map = (char *)
2875 alloca (highest_outgoing_arg_in_use);
2876 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2877 highest_outgoing_arg_in_use = 0;
2879 allocate_dynamic_stack_space (push_size, NULL_RTX,
2882 /* If argument evaluation might modify the stack pointer,
2883 copy the address of the argument list to a register. */
2884 for (i = 0; i < num_actuals; i++)
2885 if (args[i].pass_on_stack)
2887 argblock = copy_addr_to_reg (argblock);
2894 compute_argument_addresses (args, argblock, num_actuals);
2896 #ifdef PREFERRED_STACK_BOUNDARY
2897 /* If we push args individually in reverse order, perform stack alignment
2898 before the first push (the last arg). */
2899 if (PUSH_ARGS_REVERSED && argblock == 0
2900 && adjusted_args_size.constant != unadjusted_args_size)
2902 /* When the stack adjustment is pending, we get better code
2903 by combining the adjustments. */
2904 if (pending_stack_adjust
2905 && ! (flags & (ECF_CONST | ECF_PURE))
2906 && ! inhibit_defer_pop)
2908 pending_stack_adjust
2909 = (combine_pending_stack_adjustment_and_call
2910 (unadjusted_args_size,
2911 &adjusted_args_size,
2912 preferred_unit_stack_boundary));
2913 do_pending_stack_adjust ();
2915 else if (argblock == 0)
2916 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2917 - unadjusted_args_size));
2919 /* Now that the stack is properly aligned, pops can't safely
2920 be deferred during the evaluation of the arguments. */
2924 /* Don't try to defer pops if preallocating, not even from the first arg,
2925 since ARGBLOCK probably refers to the SP. */
2929 funexp = rtx_for_function_call (fndecl, exp);
2931 /* Figure out the register where the value, if any, will come back. */
2933 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2934 && ! structure_value_addr)
2936 if (pcc_struct_value)
2937 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2938 fndecl, (pass == 0));
2940 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2943 /* Precompute all register parameters. It isn't safe to compute anything
2944 once we have started filling any specific hard regs. */
2945 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2947 #ifdef REG_PARM_STACK_SPACE
2948 /* Save the fixed argument area if it's part of the caller's frame and
2949 is clobbered by argument setup for this call. */
2950 if (ACCUMULATE_OUTGOING_ARGS && pass)
2951 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2952 &low_to_save, &high_to_save);
2955 /* Now store (and compute if necessary) all non-register parms.
2956 These come before register parms, since they can require block-moves,
2957 which could clobber the registers used for register parms.
2958 Parms which have partial registers are not stored here,
2959 but we do preallocate space here if they want that. */
2961 for (i = 0; i < num_actuals; i++)
2962 if (args[i].reg == 0 || args[i].pass_on_stack)
2964 rtx before_arg = get_last_insn ();
2966 if (store_one_arg (&args[i], argblock, flags,
2967 adjusted_args_size.var != 0,
2968 reg_parm_stack_space)
2970 && check_sibcall_argument_overlap (before_arg,
2972 sibcall_failure = 1;
2975 /* If we have a parm that is passed in registers but not in memory
2976 and whose alignment does not permit a direct copy into registers,
2977 make a group of pseudos that correspond to each register that we
2979 if (STRICT_ALIGNMENT)
2980 store_unaligned_arguments_into_pseudos (args, num_actuals);
2982 /* Now store any partially-in-registers parm.
2983 This is the last place a block-move can happen. */
2985 for (i = 0; i < num_actuals; i++)
2986 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2988 rtx before_arg = get_last_insn ();
2990 if (store_one_arg (&args[i], argblock, flags,
2991 adjusted_args_size.var != 0,
2992 reg_parm_stack_space)
2994 && check_sibcall_argument_overlap (before_arg,
2996 sibcall_failure = 1;
2999 #ifdef PREFERRED_STACK_BOUNDARY
3000 /* If we pushed args in forward order, perform stack alignment
3001 after pushing the last arg. */
3002 if (!PUSH_ARGS_REVERSED && argblock == 0)
3003 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3004 - unadjusted_args_size));
3007 /* If register arguments require space on the stack and stack space
3008 was not preallocated, allocate stack space here for arguments
3009 passed in registers. */
3010 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3011 if (!ACCUMULATE_OUTGOING_ARGS
3012 && must_preallocate == 0 && reg_parm_stack_space > 0)
3013 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3016 /* Pass the function the address in which to return a
3018 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3020 emit_move_insn (struct_value_rtx,
3022 force_operand (structure_value_addr,
3025 /* Mark the memory for the aggregate as write-only. */
3026 if (current_function_check_memory_usage)
3027 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK,
3029 structure_value_addr, ptr_mode,
3030 GEN_INT (struct_value_size),
3031 TYPE_MODE (sizetype),
3032 GEN_INT (MEMORY_USE_WO),
3033 TYPE_MODE (integer_type_node));
3035 if (GET_CODE (struct_value_rtx) == REG)
3036 use_reg (&call_fusage, struct_value_rtx);
3039 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3042 load_register_parameters (args, num_actuals, &call_fusage, flags);
3044 /* Perform postincrements before actually calling the function. */
3047 /* Save a pointer to the last insn before the call, so that we can
3048 later safely search backwards to find the CALL_INSN. */
3049 before_call = get_last_insn ();
3051 /* Set up next argument register. For sibling calls on machines
3052 with register windows this should be the incoming register. */
3053 #ifdef FUNCTION_INCOMING_ARG
3055 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3059 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3062 /* All arguments and registers used for the call must be set up by
3065 #ifdef PREFERRED_STACK_BOUNDARY
3066 /* Stack must be properly aligned now. */
3067 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3071 /* Generate the actual call instruction. */
3072 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3073 adjusted_args_size.constant, struct_value_size,
3074 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3077 /* Verify that we've deallocated all the stack we used. */
3079 && old_stack_allocated != stack_pointer_delta - pending_stack_adjust)
3082 /* If call is cse'able, make appropriate pair of reg-notes around it.
3083 Test valreg so we don't crash; may safely ignore `const'
3084 if return type is void. Disable for PARALLEL return values, because
3085 we have no way to move such values into a pseudo register. */
3087 && (flags & (ECF_CONST | ECF_PURE))
3088 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
3091 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3094 /* Mark the return value as a pointer if needed. */
3095 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3096 mark_reg_pointer (temp, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3098 /* Construct an "equal form" for the value which mentions all the
3099 arguments in order as well as the function name. */
3100 for (i = 0; i < num_actuals; i++)
3101 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
3102 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3104 insns = get_insns ();
3107 if (flags & ECF_PURE)
3108 note = gen_rtx_EXPR_LIST (VOIDmode,
3109 gen_rtx_USE (VOIDmode,
3110 gen_rtx_MEM (BLKmode,
3111 gen_rtx_SCRATCH (VOIDmode))), note);
3113 emit_libcall_block (insns, temp, valreg, note);
3117 else if (flags & (ECF_CONST | ECF_PURE))
3119 /* Otherwise, just write out the sequence without a note. */
3120 rtx insns = get_insns ();
3125 else if (flags & ECF_MALLOC)
3127 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3130 /* The return value from a malloc-like function is a pointer. */
3131 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3132 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3134 emit_move_insn (temp, valreg);
3136 /* The return value from a malloc-like function can not alias
3138 last = get_last_insn ();
3140 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3142 /* Write out the sequence. */
3143 insns = get_insns ();
3149 /* For calls to `setjmp', etc., inform flow.c it should complain
3150 if nonvolatile values are live. For functions that cannot return,
3151 inform flow that control does not fall through. */
3153 if ((flags & (ECF_RETURNS_TWICE | ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3155 /* The barrier or NOTE_INSN_SETJMP note must be emitted
3156 immediately after the CALL_INSN. Some ports emit more
3157 than just a CALL_INSN above, so we must search for it here. */
3159 rtx last = get_last_insn ();
3160 while (GET_CODE (last) != CALL_INSN)
3162 last = PREV_INSN (last);
3163 /* There was no CALL_INSN? */
3164 if (last == before_call)
3168 if (flags & ECF_RETURNS_TWICE)
3170 emit_note_after (NOTE_INSN_SETJMP, last);
3171 current_function_calls_setjmp = 1;
3174 emit_barrier_after (last);
3177 if (flags & ECF_LONGJMP)
3178 current_function_calls_longjmp = 1;
3180 /* If this function is returning into a memory location marked as
3181 readonly, it means it is initializing that location. But we normally
3182 treat functions as not clobbering such locations, so we need to
3183 specify that this one does. */
3184 if (target != 0 && GET_CODE (target) == MEM
3185 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
3186 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
3188 /* If value type not void, return an rtx for the value. */
3190 /* If there are cleanups to be called, don't use a hard reg as target.
3191 We need to double check this and see if it matters anymore. */
3192 if (any_pending_cleanups (1))
3194 if (target && REG_P (target)
3195 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3197 sibcall_failure = 1;
3200 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3203 target = const0_rtx;
3205 else if (structure_value_addr)
3207 if (target == 0 || GET_CODE (target) != MEM)
3210 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3211 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3212 structure_value_addr));
3213 set_mem_attributes (target, exp, 1);
3216 else if (pcc_struct_value)
3218 /* This is the special C++ case where we need to
3219 know what the true target was. We take care to
3220 never use this value more than once in one expression. */
3221 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3222 copy_to_reg (valreg));
3223 set_mem_attributes (target, exp, 1);
3225 /* Handle calls that return values in multiple non-contiguous locations.
3226 The Irix 6 ABI has examples of this. */
3227 else if (GET_CODE (valreg) == PARALLEL)
3229 int bytes = int_size_in_bytes (TREE_TYPE (exp));
3233 target = assign_stack_temp (TYPE_MODE (TREE_TYPE (exp)),
3235 MEM_SET_IN_STRUCT_P (target, AGGREGATE_TYPE_P (TREE_TYPE (exp)));
3236 preserve_temp_slots (target);
3239 if (! rtx_equal_p (target, valreg))
3240 emit_group_store (target, valreg, bytes,
3241 TYPE_ALIGN (TREE_TYPE (exp)));
3243 /* We can not support sibling calls for this case. */
3244 sibcall_failure = 1;
3247 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3248 && GET_MODE (target) == GET_MODE (valreg))
3250 /* TARGET and VALREG cannot be equal at this point because the
3251 latter would not have REG_FUNCTION_VALUE_P true, while the
3252 former would if it were referring to the same register.
3254 If they refer to the same register, this move will be a no-op,
3255 except when function inlining is being done. */
3256 emit_move_insn (target, valreg);
3258 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3260 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3262 /* We can not support sibling calls for this case. */
3263 sibcall_failure = 1;
3266 target = copy_to_reg (valreg);
3268 #ifdef PROMOTE_FUNCTION_RETURN
3269 /* If we promoted this return value, make the proper SUBREG. TARGET
3270 might be const0_rtx here, so be careful. */
3271 if (GET_CODE (target) == REG
3272 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3273 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3275 tree type = TREE_TYPE (exp);
3276 int unsignedp = TREE_UNSIGNED (type);
3278 /* If we don't promote as expected, something is wrong. */
3279 if (GET_MODE (target)
3280 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3283 target = gen_rtx_SUBREG (TYPE_MODE (type), target, 0);
3284 SUBREG_PROMOTED_VAR_P (target) = 1;
3285 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
3289 /* If size of args is variable or this was a constructor call for a stack
3290 argument, restore saved stack-pointer value. */
3292 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3294 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3295 pending_stack_adjust = old_pending_adj;
3296 stack_arg_under_construction = old_stack_arg_under_construction;
3297 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3298 stack_usage_map = initial_stack_usage_map;
3299 sibcall_failure = 1;
3301 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3303 #ifdef REG_PARM_STACK_SPACE
3306 restore_fixed_argument_area (save_area, argblock,
3307 high_to_save, low_to_save);
3311 /* If we saved any argument areas, restore them. */
3312 for (i = 0; i < num_actuals; i++)
3313 if (args[i].save_area)
3315 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3317 = gen_rtx_MEM (save_mode,
3318 memory_address (save_mode,
3319 XEXP (args[i].stack_slot, 0)));
3321 if (save_mode != BLKmode)
3322 emit_move_insn (stack_area, args[i].save_area);
3324 emit_block_move (stack_area,
3325 validize_mem (args[i].save_area),
3326 GEN_INT (args[i].size.constant),
3330 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3331 stack_usage_map = initial_stack_usage_map;
3334 /* If this was alloca, record the new stack level for nonlocal gotos.
3335 Check for the handler slots since we might not have a save area
3336 for non-local gotos. */
3338 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3339 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3343 /* Free up storage we no longer need. */
3344 for (i = 0; i < num_actuals; ++i)
3345 if (args[i].aligned_regs)
3346 free (args[i].aligned_regs);
3350 /* Undo the fake expand_start_target_temps we did earlier. If
3351 there had been any cleanups created, we've already set
3353 expand_end_target_temps ();
3356 insns = get_insns ();
3361 tail_call_insns = insns;
3363 /* Restore the pending stack adjustment now that we have
3364 finished generating the sibling call sequence. */
3366 pending_stack_adjust = save_pending_stack_adjust;
3367 stack_pointer_delta = save_stack_pointer_delta;
3369 /* Prepare arg structure for next iteration. */
3370 for (i = 0; i < num_actuals; i++)
3373 args[i].aligned_regs = 0;
3377 sbitmap_free (stored_args_map);
3380 normal_call_insns = insns;
3382 /* If something prevents making this a sibling call,
3383 zero out the sequence. */
3384 if (sibcall_failure)
3385 tail_call_insns = NULL_RTX;
3388 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3389 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3390 can happen if the arguments to this function call an inline
3391 function who's expansion contains another CALL_PLACEHOLDER.
3393 If there are any C_Ps in any of these sequences, replace them
3394 with their normal call. */
3396 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3397 if (GET_CODE (insn) == CALL_INSN
3398 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3399 replace_call_placeholder (insn, sibcall_use_normal);
3401 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3402 if (GET_CODE (insn) == CALL_INSN
3403 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3404 replace_call_placeholder (insn, sibcall_use_normal);
3406 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3407 if (GET_CODE (insn) == CALL_INSN
3408 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3409 replace_call_placeholder (insn, sibcall_use_normal);
3411 /* If this was a potential tail recursion site, then emit a
3412 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3413 One of them will be selected later. */
3414 if (tail_recursion_insns || tail_call_insns)
3416 /* The tail recursion label must be kept around. We could expose
3417 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3418 and makes determining true tail recursion sites difficult.
3420 So we set LABEL_PRESERVE_P here, then clear it when we select
3421 one of the call sequences after rtl generation is complete. */
3422 if (tail_recursion_insns)
3423 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3424 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3426 tail_recursion_insns,
3427 tail_recursion_label));
3430 emit_insns (normal_call_insns);
3432 currently_expanding_call--;
3434 /* If this function returns with the stack pointer depressed, ensure
3435 this block saves and restores the stack pointer, show it was
3436 changed, and adjust for any outgoing arg space. */
3437 if (flags & ECF_SP_DEPRESSED)
3439 clear_pending_stack_adjust ();
3440 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3441 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3442 save_stack_pointer ();
3448 /* Returns nonzero if FUN is the symbol for a library function which can
3452 libfunc_nothrow (fun)
3455 if (fun == throw_libfunc
3456 || fun == rethrow_libfunc
3457 || fun == sjthrow_libfunc
3458 || fun == sjpopnthrow_libfunc)
3464 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3465 The RETVAL parameter specifies whether return value needs to be saved, other
3466 parameters are documented in the emit_library_call function bellow. */
3468 emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3472 enum libcall_type fn_type;
3473 enum machine_mode outmode;
3477 /* Total size in bytes of all the stack-parms scanned so far. */
3478 struct args_size args_size;
3479 /* Size of arguments before any adjustments (such as rounding). */
3480 struct args_size original_args_size;
3481 register int argnum;
3485 struct args_size alignment_pad;
3487 CUMULATIVE_ARGS args_so_far;
3491 enum machine_mode mode;
3494 struct args_size offset;
3495 struct args_size size;
3499 int old_inhibit_defer_pop = inhibit_defer_pop;
3500 rtx call_fusage = 0;
3503 int pcc_struct_value = 0;
3504 int struct_value_size = 0;
3506 int reg_parm_stack_space = 0;
3509 #ifdef REG_PARM_STACK_SPACE
3510 /* Define the boundary of the register parm stack space that needs to be
3512 int low_to_save = -1, high_to_save = 0;
3513 rtx save_area = 0; /* Place that it is saved. */
3516 /* Size of the stack reserved for parameter registers. */
3517 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3518 char *initial_stack_usage_map = stack_usage_map;
3520 #ifdef REG_PARM_STACK_SPACE
3521 #ifdef MAYBE_REG_PARM_STACK_SPACE
3522 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3524 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3528 if (fn_type == LCT_CONST_MAKE_BLOCK)
3530 else if (fn_type == LCT_PURE_MAKE_BLOCK)
3534 if (libfunc_nothrow (fun))
3535 flags |= ECF_NOTHROW;
3537 #ifdef PREFERRED_STACK_BOUNDARY
3538 /* Ensure current function's preferred stack boundary is at least
3540 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3541 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3544 /* If this kind of value comes back in memory,
3545 decide where in memory it should come back. */
3546 if (outmode != VOIDmode && aggregate_value_p (type_for_mode (outmode, 0)))
3548 #ifdef PCC_STATIC_STRUCT_RETURN
3550 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
3552 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3553 pcc_struct_value = 1;
3555 value = gen_reg_rtx (outmode);
3556 #else /* not PCC_STATIC_STRUCT_RETURN */
3557 struct_value_size = GET_MODE_SIZE (outmode);
3558 if (value != 0 && GET_CODE (value) == MEM)
3561 mem_value = assign_stack_temp (outmode, GET_MODE_SIZE (outmode), 0);
3564 /* This call returns a big structure. */
3565 flags &= ~(ECF_CONST | ECF_PURE);
3568 /* ??? Unfinished: must pass the memory address as an argument. */
3570 /* Copy all the libcall-arguments out of the varargs data
3571 and into a vector ARGVEC.
3573 Compute how to pass each argument. We only support a very small subset
3574 of the full argument passing conventions to limit complexity here since
3575 library functions shouldn't have many args. */
3577 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3578 memset ((char *) argvec, 0, (nargs + 1) * sizeof (struct arg));
3580 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3582 args_size.constant = 0;
3587 /* Now we are about to start emitting insns that can be deleted
3588 if a libcall is deleted. */
3589 if (flags & (ECF_CONST | ECF_PURE))
3594 /* If there's a structure value address to be passed,
3595 either pass it in the special place, or pass it as an extra argument. */
3596 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3598 rtx addr = XEXP (mem_value, 0);
3601 /* Make sure it is a reasonable operand for a move or push insn. */
3602 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3603 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3604 addr = force_operand (addr, NULL_RTX);
3606 argvec[count].value = addr;
3607 argvec[count].mode = Pmode;
3608 argvec[count].partial = 0;
3610 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3611 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3612 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3616 locate_and_pad_parm (Pmode, NULL_TREE,
3617 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3620 argvec[count].reg != 0,
3622 NULL_TREE, &args_size, &argvec[count].offset,
3623 &argvec[count].size, &alignment_pad);
3625 if (argvec[count].reg == 0 || argvec[count].partial != 0
3626 || reg_parm_stack_space > 0)
3627 args_size.constant += argvec[count].size.constant;
3629 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3634 for (; count < nargs; count++)
3636 rtx val = va_arg (p, rtx);
3637 enum machine_mode mode = va_arg (p, enum machine_mode);
3639 /* We cannot convert the arg value to the mode the library wants here;
3640 must do it earlier where we know the signedness of the arg. */
3642 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3645 /* On some machines, there's no way to pass a float to a library fcn.
3646 Pass it as a double instead. */
3647 #ifdef LIBGCC_NEEDS_DOUBLE
3648 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3649 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3652 /* There's no need to call protect_from_queue, because
3653 either emit_move_insn or emit_push_insn will do that. */
3655 /* Make sure it is a reasonable operand for a move or push insn. */
3656 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3657 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3658 val = force_operand (val, NULL_RTX);
3660 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3661 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3663 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
3664 be viewed as just an efficiency improvement. */
3665 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
3666 emit_move_insn (slot, val);
3667 val = force_operand (XEXP (slot, 0), NULL_RTX);
3672 argvec[count].value = val;
3673 argvec[count].mode = mode;
3675 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3677 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3678 argvec[count].partial
3679 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3681 argvec[count].partial = 0;
3684 locate_and_pad_parm (mode, NULL_TREE,
3685 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3688 argvec[count].reg != 0,
3690 NULL_TREE, &args_size, &argvec[count].offset,
3691 &argvec[count].size, &alignment_pad);
3693 if (argvec[count].size.var)
3696 if (reg_parm_stack_space == 0 && argvec[count].partial)
3697 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3699 if (argvec[count].reg == 0 || argvec[count].partial != 0
3700 || reg_parm_stack_space > 0)
3701 args_size.constant += argvec[count].size.constant;
3703 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3706 #ifdef FINAL_REG_PARM_STACK_SPACE
3707 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3710 /* If this machine requires an external definition for library
3711 functions, write one out. */
3712 assemble_external_libcall (fun);
3714 original_args_size = args_size;
3715 #ifdef PREFERRED_STACK_BOUNDARY
3716 args_size.constant = (((args_size.constant
3717 + stack_pointer_delta
3721 - stack_pointer_delta);
3724 args_size.constant = MAX (args_size.constant,
3725 reg_parm_stack_space);
3727 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3728 args_size.constant -= reg_parm_stack_space;
3731 if (args_size.constant > current_function_outgoing_args_size)
3732 current_function_outgoing_args_size = args_size.constant;
3734 if (ACCUMULATE_OUTGOING_ARGS)
3736 /* Since the stack pointer will never be pushed, it is possible for
3737 the evaluation of a parm to clobber something we have already
3738 written to the stack. Since most function calls on RISC machines
3739 do not use the stack, this is uncommon, but must work correctly.
3741 Therefore, we save any area of the stack that was already written
3742 and that we are using. Here we set up to do this by making a new
3743 stack usage map from the old one.
3745 Another approach might be to try to reorder the argument
3746 evaluations to avoid this conflicting stack usage. */
3748 needed = args_size.constant;
3750 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3751 /* Since we will be writing into the entire argument area, the
3752 map must be allocated for its entire size, not just the part that
3753 is the responsibility of the caller. */
3754 needed += reg_parm_stack_space;
3757 #ifdef ARGS_GROW_DOWNWARD
3758 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3761 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3764 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3766 if (initial_highest_arg_in_use)
3767 memcpy (stack_usage_map, initial_stack_usage_map,
3768 initial_highest_arg_in_use);
3770 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3771 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3772 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3775 /* The address of the outgoing argument list must not be copied to a
3776 register here, because argblock would be left pointing to the
3777 wrong place after the call to allocate_dynamic_stack_space below. */
3779 argblock = virtual_outgoing_args_rtx;
3784 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3787 #ifdef PREFERRED_STACK_BOUNDARY
3788 /* If we push args individually in reverse order, perform stack alignment
3789 before the first push (the last arg). */
3790 if (argblock == 0 && PUSH_ARGS_REVERSED)
3791 anti_adjust_stack (GEN_INT (args_size.constant
3792 - original_args_size.constant));
3795 if (PUSH_ARGS_REVERSED)
3806 #ifdef REG_PARM_STACK_SPACE
3807 if (ACCUMULATE_OUTGOING_ARGS)
3809 /* The argument list is the property of the called routine and it
3810 may clobber it. If the fixed area has been used for previous
3811 parameters, we must save and restore it.
3813 Here we compute the boundary of the that needs to be saved, if any. */
3815 #ifdef ARGS_GROW_DOWNWARD
3816 for (count = 0; count < reg_parm_stack_space + 1; count++)
3818 for (count = 0; count < reg_parm_stack_space; count++)
3821 if (count >= highest_outgoing_arg_in_use
3822 || stack_usage_map[count] == 0)
3825 if (low_to_save == -1)
3826 low_to_save = count;
3828 high_to_save = count;
3831 if (low_to_save >= 0)
3833 int num_to_save = high_to_save - low_to_save + 1;
3834 enum machine_mode save_mode
3835 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3838 /* If we don't have the required alignment, must do this in BLKmode. */
3839 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3840 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3841 save_mode = BLKmode;
3843 #ifdef ARGS_GROW_DOWNWARD
3844 stack_area = gen_rtx_MEM (save_mode,
3845 memory_address (save_mode,
3846 plus_constant (argblock,
3849 stack_area = gen_rtx_MEM (save_mode,
3850 memory_address (save_mode,
3851 plus_constant (argblock,
3854 if (save_mode == BLKmode)
3856 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3857 emit_block_move (validize_mem (save_area), stack_area,
3858 GEN_INT (num_to_save), PARM_BOUNDARY);
3862 save_area = gen_reg_rtx (save_mode);
3863 emit_move_insn (save_area, stack_area);
3869 /* Push the args that need to be pushed. */
3871 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3872 are to be pushed. */
3873 for (count = 0; count < nargs; count++, argnum += inc)
3875 register enum machine_mode mode = argvec[argnum].mode;
3876 register rtx val = argvec[argnum].value;
3877 rtx reg = argvec[argnum].reg;
3878 int partial = argvec[argnum].partial;
3879 int lower_bound = 0, upper_bound = 0, i;
3881 if (! (reg != 0 && partial == 0))
3883 if (ACCUMULATE_OUTGOING_ARGS)
3885 /* If this is being stored into a pre-allocated, fixed-size,
3886 stack area, save any previous data at that location. */
3888 #ifdef ARGS_GROW_DOWNWARD
3889 /* stack_slot is negative, but we want to index stack_usage_map
3890 with positive values. */
3891 upper_bound = -argvec[argnum].offset.constant + 1;
3892 lower_bound = upper_bound - argvec[argnum].size.constant;
3894 lower_bound = argvec[argnum].offset.constant;
3895 upper_bound = lower_bound + argvec[argnum].size.constant;
3898 for (i = lower_bound; i < upper_bound; i++)
3899 if (stack_usage_map[i]
3900 /* Don't store things in the fixed argument area at this
3901 point; it has already been saved. */
3902 && i > reg_parm_stack_space)
3905 if (i != upper_bound)
3907 /* We need to make a save area. See what mode we can make
3909 enum machine_mode save_mode
3910 = mode_for_size (argvec[argnum].size.constant
3918 plus_constant (argblock,
3919 argvec[argnum].offset.constant)));
3920 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3922 emit_move_insn (argvec[argnum].save_area, stack_area);
3926 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
3927 argblock, GEN_INT (argvec[argnum].offset.constant),
3928 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3930 /* Now mark the segment we just used. */
3931 if (ACCUMULATE_OUTGOING_ARGS)
3932 for (i = lower_bound; i < upper_bound; i++)
3933 stack_usage_map[i] = 1;
3939 #ifdef PREFERRED_STACK_BOUNDARY
3940 /* If we pushed args in forward order, perform stack alignment
3941 after pushing the last arg. */
3942 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3943 anti_adjust_stack (GEN_INT (args_size.constant
3944 - original_args_size.constant));
3947 if (PUSH_ARGS_REVERSED)
3952 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
3954 /* Now load any reg parms into their regs. */
3956 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3957 are to be pushed. */
3958 for (count = 0; count < nargs; count++, argnum += inc)
3960 register rtx val = argvec[argnum].value;
3961 rtx reg = argvec[argnum].reg;
3962 int partial = argvec[argnum].partial;
3964 /* Handle calls that pass values in multiple non-contiguous
3965 locations. The PA64 has examples of this for library calls. */
3966 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3967 emit_group_load (reg, val,
3968 GET_MODE_SIZE (GET_MODE (val)),
3969 GET_MODE_ALIGNMENT (GET_MODE (val)));
3970 else if (reg != 0 && partial == 0)
3971 emit_move_insn (reg, val);
3976 /* Any regs containing parms remain in use through the call. */
3977 for (count = 0; count < nargs; count++)
3979 rtx reg = argvec[count].reg;
3980 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3981 use_group_regs (&call_fusage, reg);
3983 use_reg (&call_fusage, reg);
3986 /* Pass the function the address in which to return a structure value. */
3987 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
3989 emit_move_insn (struct_value_rtx,
3991 force_operand (XEXP (mem_value, 0),
3993 if (GET_CODE (struct_value_rtx) == REG)
3994 use_reg (&call_fusage, struct_value_rtx);
3997 /* Don't allow popping to be deferred, since then
3998 cse'ing of library calls could delete a call and leave the pop. */
4000 valreg = (mem_value == 0 && outmode != VOIDmode
4001 ? hard_libcall_value (outmode) : NULL_RTX);
4003 #ifdef PREFERRED_STACK_BOUNDARY
4004 /* Stack must be properly aligned now. */
4005 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4009 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4010 will set inhibit_defer_pop to that value. */
4011 /* The return type is needed to decide how many bytes the function pops.
4012 Signedness plays no role in that, so for simplicity, we pretend it's
4013 always signed. We also assume that the list of arguments passed has
4014 no impact, so we pretend it is unknown. */
4017 get_identifier (XSTR (orgfun, 0)),
4018 build_function_type (outmode == VOIDmode ? void_type_node
4019 : type_for_mode (outmode, 0), NULL_TREE),
4020 original_args_size.constant, args_size.constant,
4022 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4024 old_inhibit_defer_pop + 1, call_fusage, flags);
4026 /* Now restore inhibit_defer_pop to its actual original value. */
4029 /* If call is cse'able, make appropriate pair of reg-notes around it.
4030 Test valreg so we don't crash; may safely ignore `const'
4031 if return type is void. Disable for PARALLEL return values, because
4032 we have no way to move such values into a pseudo register. */
4033 if ((flags & (ECF_CONST | ECF_PURE))
4034 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
4037 rtx temp = gen_reg_rtx (GET_MODE (valreg));
4041 /* Construct an "equal form" for the value which mentions all the
4042 arguments in order as well as the function name. */
4043 for (i = 0; i < nargs; i++)
4044 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4045 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4047 insns = get_insns ();
4050 if (flags & ECF_PURE)
4051 note = gen_rtx_EXPR_LIST (VOIDmode,
4052 gen_rtx_USE (VOIDmode,
4053 gen_rtx_MEM (BLKmode,
4054 gen_rtx_SCRATCH (VOIDmode))), note);
4056 emit_libcall_block (insns, temp, valreg, note);
4060 else if (flags & (ECF_CONST | ECF_PURE))
4062 /* Otherwise, just write out the sequence without a note. */
4063 rtx insns = get_insns ();
4070 /* Copy the value to the right place. */
4071 if (outmode != VOIDmode && retval)
4077 if (value != mem_value)
4078 emit_move_insn (value, mem_value);
4080 else if (value != 0)
4081 emit_move_insn (value, hard_libcall_value (outmode));
4083 value = hard_libcall_value (outmode);
4086 if (ACCUMULATE_OUTGOING_ARGS)
4088 #ifdef REG_PARM_STACK_SPACE
4091 enum machine_mode save_mode = GET_MODE (save_area);
4092 #ifdef ARGS_GROW_DOWNWARD
4094 = gen_rtx_MEM (save_mode,
4095 memory_address (save_mode,
4096 plus_constant (argblock,
4100 = gen_rtx_MEM (save_mode,
4101 memory_address (save_mode,
4102 plus_constant (argblock, low_to_save)));
4104 if (save_mode != BLKmode)
4105 emit_move_insn (stack_area, save_area);
4107 emit_block_move (stack_area, validize_mem (save_area),
4108 GEN_INT (high_to_save - low_to_save + 1),
4113 /* If we saved any argument areas, restore them. */
4114 for (count = 0; count < nargs; count++)
4115 if (argvec[count].save_area)
4117 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4119 = gen_rtx_MEM (save_mode,
4122 plus_constant (argblock,
4123 argvec[count].offset.constant)));
4125 emit_move_insn (stack_area, argvec[count].save_area);
4128 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4129 stack_usage_map = initial_stack_usage_map;
4136 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4137 (emitting the queue unless NO_QUEUE is nonzero),
4138 for a value of mode OUTMODE,
4139 with NARGS different arguments, passed as alternating rtx values
4140 and machine_modes to convert them to.
4141 The rtx values should have been passed through protect_from_queue already.
4143 FN_TYPE will is zero for `normal' calls, one for `const' calls, wich
4144 which will be enclosed in REG_LIBCALL/REG_RETVAL notes and two for `pure'
4145 calls, that are handled like `const' calls with extra
4146 (use (memory (scratch)). */
4149 emit_library_call VPARAMS((rtx orgfun, enum libcall_type fn_type,
4150 enum machine_mode outmode, int nargs, ...))
4152 #ifndef ANSI_PROTOTYPES
4155 enum machine_mode outmode;
4160 VA_START (p, nargs);
4162 #ifndef ANSI_PROTOTYPES
4163 orgfun = va_arg (p, rtx);
4164 fn_type = va_arg (p, int);
4165 outmode = va_arg (p, enum machine_mode);
4166 nargs = va_arg (p, int);
4169 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4174 /* Like emit_library_call except that an extra argument, VALUE,
4175 comes second and says where to store the result.
4176 (If VALUE is zero, this function chooses a convenient way
4177 to return the value.
4179 This function returns an rtx for where the value is to be found.
4180 If VALUE is nonzero, VALUE is returned. */
4183 emit_library_call_value VPARAMS((rtx orgfun, rtx value,
4184 enum libcall_type fn_type,
4185 enum machine_mode outmode, int nargs, ...))
4187 #ifndef ANSI_PROTOTYPES
4191 enum machine_mode outmode;
4196 VA_START (p, nargs);
4198 #ifndef ANSI_PROTOTYPES
4199 orgfun = va_arg (p, rtx);
4200 value = va_arg (p, rtx);
4201 fn_type = va_arg (p, int);
4202 outmode = va_arg (p, enum machine_mode);
4203 nargs = va_arg (p, int);
4206 value = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode, nargs, p);
4214 /* Return an rtx which represents a suitable home on the stack
4215 given TYPE, the type of the argument looking for a home.
4216 This is called only for BLKmode arguments.
4218 SIZE is the size needed for this target.
4219 ARGS_ADDR is the address of the bottom of the argument block for this call.
4220 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
4221 if this machine uses push insns. */
4224 target_for_arg (type, size, args_addr, offset)
4228 struct args_size offset;
4231 rtx offset_rtx = ARGS_SIZE_RTX (offset);
4233 /* We do not call memory_address if possible,
4234 because we want to address as close to the stack
4235 as possible. For non-variable sized arguments,
4236 this will be stack-pointer relative addressing. */
4237 if (GET_CODE (offset_rtx) == CONST_INT)
4238 target = plus_constant (args_addr, INTVAL (offset_rtx));
4241 /* I have no idea how to guarantee that this
4242 will work in the presence of register parameters. */
4243 target = gen_rtx_PLUS (Pmode, args_addr, offset_rtx);
4244 target = memory_address (QImode, target);
4247 return gen_rtx_MEM (BLKmode, target);
4251 /* Store a single argument for a function call
4252 into the register or memory area where it must be passed.
4253 *ARG describes the argument value and where to pass it.
4255 ARGBLOCK is the address of the stack-block for all the arguments,
4256 or 0 on a machine where arguments are pushed individually.
4258 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4259 so must be careful about how the stack is used.
4261 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4262 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4263 that we need not worry about saving and restoring the stack.
4265 FNDECL is the declaration of the function we are calling.
4267 Return non-zero if this arg should cause sibcall failure,
4271 store_one_arg (arg, argblock, flags, variable_size, reg_parm_stack_space)
4272 struct arg_data *arg;
4275 int variable_size ATTRIBUTE_UNUSED;
4276 int reg_parm_stack_space;
4278 register tree pval = arg->tree_value;
4282 int i, lower_bound = 0, upper_bound = 0;
4283 int sibcall_failure = 0;
4285 if (TREE_CODE (pval) == ERROR_MARK)
4288 /* Push a new temporary level for any temporaries we make for
4292 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4294 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4295 save any previous data at that location. */
4296 if (argblock && ! variable_size && arg->stack)
4298 #ifdef ARGS_GROW_DOWNWARD
4299 /* stack_slot is negative, but we want to index stack_usage_map
4300 with positive values. */
4301 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4302 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4306 lower_bound = upper_bound - arg->size.constant;
4308 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4309 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4313 upper_bound = lower_bound + arg->size.constant;
4316 for (i = lower_bound; i < upper_bound; i++)
4317 if (stack_usage_map[i]
4318 /* Don't store things in the fixed argument area at this point;
4319 it has already been saved. */
4320 && i > reg_parm_stack_space)
4323 if (i != upper_bound)
4325 /* We need to make a save area. See what mode we can make it. */
4326 enum machine_mode save_mode
4327 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
4329 = gen_rtx_MEM (save_mode,
4330 memory_address (save_mode,
4331 XEXP (arg->stack_slot, 0)));
4333 if (save_mode == BLKmode)
4335 arg->save_area = assign_stack_temp (BLKmode,
4336 arg->size.constant, 0);
4337 MEM_SET_IN_STRUCT_P (arg->save_area,
4338 AGGREGATE_TYPE_P (TREE_TYPE
4339 (arg->tree_value)));
4340 preserve_temp_slots (arg->save_area);
4341 emit_block_move (validize_mem (arg->save_area), stack_area,
4342 GEN_INT (arg->size.constant),
4347 arg->save_area = gen_reg_rtx (save_mode);
4348 emit_move_insn (arg->save_area, stack_area);
4352 /* Now that we have saved any slots that will be overwritten by this
4353 store, mark all slots this store will use. We must do this before
4354 we actually expand the argument since the expansion itself may
4355 trigger library calls which might need to use the same stack slot. */
4356 if (argblock && ! variable_size && arg->stack)
4357 for (i = lower_bound; i < upper_bound; i++)
4358 stack_usage_map[i] = 1;
4361 /* If this isn't going to be placed on both the stack and in registers,
4362 set up the register and number of words. */
4363 if (! arg->pass_on_stack)
4364 reg = arg->reg, partial = arg->partial;
4366 if (reg != 0 && partial == 0)
4367 /* Being passed entirely in a register. We shouldn't be called in
4371 /* If this arg needs special alignment, don't load the registers
4373 if (arg->n_aligned_regs != 0)
4376 /* If this is being passed partially in a register, we can't evaluate
4377 it directly into its stack slot. Otherwise, we can. */
4378 if (arg->value == 0)
4380 /* stack_arg_under_construction is nonzero if a function argument is
4381 being evaluated directly into the outgoing argument list and
4382 expand_call must take special action to preserve the argument list
4383 if it is called recursively.
4385 For scalar function arguments stack_usage_map is sufficient to
4386 determine which stack slots must be saved and restored. Scalar
4387 arguments in general have pass_on_stack == 0.
4389 If this argument is initialized by a function which takes the
4390 address of the argument (a C++ constructor or a C function
4391 returning a BLKmode structure), then stack_usage_map is
4392 insufficient and expand_call must push the stack around the
4393 function call. Such arguments have pass_on_stack == 1.
4395 Note that it is always safe to set stack_arg_under_construction,
4396 but this generates suboptimal code if set when not needed. */
4398 if (arg->pass_on_stack)
4399 stack_arg_under_construction++;
4401 arg->value = expand_expr (pval,
4403 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4404 ? NULL_RTX : arg->stack,
4407 /* If we are promoting object (or for any other reason) the mode
4408 doesn't agree, convert the mode. */
4410 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4411 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4412 arg->value, arg->unsignedp);
4414 if (arg->pass_on_stack)
4415 stack_arg_under_construction--;
4418 /* Don't allow anything left on stack from computation
4419 of argument to alloca. */
4420 if (flags & ECF_MAY_BE_ALLOCA)
4421 do_pending_stack_adjust ();
4423 if (arg->value == arg->stack)
4425 /* If the value is already in the stack slot, we are done. */
4426 if (current_function_check_memory_usage && GET_CODE (arg->stack) == MEM)
4428 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK,
4429 VOIDmode, 3, XEXP (arg->stack, 0), Pmode,
4430 ARGS_SIZE_RTX (arg->size),
4431 TYPE_MODE (sizetype),
4432 GEN_INT (MEMORY_USE_RW),
4433 TYPE_MODE (integer_type_node));
4436 else if (arg->mode != BLKmode)
4440 /* Argument is a scalar, not entirely passed in registers.
4441 (If part is passed in registers, arg->partial says how much
4442 and emit_push_insn will take care of putting it there.)
4444 Push it, and if its size is less than the
4445 amount of space allocated to it,
4446 also bump stack pointer by the additional space.
4447 Note that in C the default argument promotions
4448 will prevent such mismatches. */
4450 size = GET_MODE_SIZE (arg->mode);
4451 /* Compute how much space the push instruction will push.
4452 On many machines, pushing a byte will advance the stack
4453 pointer by a halfword. */
4454 #ifdef PUSH_ROUNDING
4455 size = PUSH_ROUNDING (size);
4459 /* Compute how much space the argument should get:
4460 round up to a multiple of the alignment for arguments. */
4461 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4462 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4463 / (PARM_BOUNDARY / BITS_PER_UNIT))
4464 * (PARM_BOUNDARY / BITS_PER_UNIT));
4466 /* This isn't already where we want it on the stack, so put it there.
4467 This can either be done with push or copy insns. */
4468 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX, 0,
4469 partial, reg, used - size, argblock,
4470 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4471 ARGS_SIZE_RTX (arg->alignment_pad));
4475 /* BLKmode, at least partly to be pushed. */
4477 register int excess;
4480 /* Pushing a nonscalar.
4481 If part is passed in registers, PARTIAL says how much
4482 and emit_push_insn will take care of putting it there. */
4484 /* Round its size up to a multiple
4485 of the allocation unit for arguments. */
4487 if (arg->size.var != 0)
4490 size_rtx = ARGS_SIZE_RTX (arg->size);
4494 /* PUSH_ROUNDING has no effect on us, because
4495 emit_push_insn for BLKmode is careful to avoid it. */
4496 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4497 + partial * UNITS_PER_WORD);
4498 size_rtx = expr_size (pval);
4501 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4503 /* emit_push_insn might not work properly if arg->value and
4504 argblock + arg->offset areas overlap. */
4508 if (XEXP (x, 0) == current_function_internal_arg_pointer
4509 || (GET_CODE (XEXP (x, 0)) == PLUS
4510 && XEXP (XEXP (x, 0), 0) ==
4511 current_function_internal_arg_pointer
4512 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4514 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4515 i = INTVAL (XEXP (XEXP (x, 0), 1));
4517 /* expand_call should ensure this */
4518 if (arg->offset.var || GET_CODE (size_rtx) != CONST_INT)
4521 if (arg->offset.constant > i)
4523 if (arg->offset.constant < i + INTVAL (size_rtx))
4524 sibcall_failure = 1;
4526 else if (arg->offset.constant < i)
4528 if (i < arg->offset.constant + INTVAL (size_rtx))
4529 sibcall_failure = 1;
4534 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4535 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg, excess,
4536 argblock, ARGS_SIZE_RTX (arg->offset),
4537 reg_parm_stack_space,
4538 ARGS_SIZE_RTX (arg->alignment_pad));
4541 /* Unless this is a partially-in-register argument, the argument is now
4544 ??? Note that this can change arg->value from arg->stack to
4545 arg->stack_slot and it matters when they are not the same.
4546 It isn't totally clear that this is correct in all cases. */
4548 arg->value = arg->stack_slot;
4550 /* Once we have pushed something, pops can't safely
4551 be deferred during the rest of the arguments. */
4554 /* ANSI doesn't require a sequence point here,
4555 but PCC has one, so this will avoid some problems. */
4558 /* Free any temporary slots made in processing this argument. Show
4559 that we might have taken the address of something and pushed that
4561 preserve_temp_slots (NULL_RTX);
4565 return sibcall_failure;