1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998
3 1999, 2000 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
30 #include "insn-flags.h"
37 #ifndef ACCUMULATE_OUTGOING_ARGS
38 #define ACCUMULATE_OUTGOING_ARGS 0
41 /* Supply a default definition for PUSH_ARGS. */
44 #define PUSH_ARGS !ACCUMULATE_OUTGOING_ARGS
50 #if !defined FUNCTION_OK_FOR_SIBCALL
51 #define FUNCTION_OK_FOR_SIBCALL(DECL) 1
54 #if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY
55 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
58 /* Decide whether a function's arguments should be processed
59 from first to last or from last to first.
61 They should if the stack and args grow in opposite directions, but
62 only if we have push insns. */
66 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
67 #define PUSH_ARGS_REVERSED PUSH_ARGS
72 #ifndef PUSH_ARGS_REVERSED
73 #define PUSH_ARGS_REVERSED 0
76 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
77 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
79 /* Data structure and subroutines used within expand_call. */
83 /* Tree node for this argument. */
85 /* Mode for value; TYPE_MODE unless promoted. */
86 enum machine_mode mode;
87 /* Current RTL value for argument, or 0 if it isn't precomputed. */
89 /* Initially-compute RTL value for argument; only for const functions. */
91 /* Register to pass this argument in, 0 if passed on stack, or an
92 PARALLEL if the arg is to be copied into multiple non-contiguous
95 /* Register to pass this argument in when generating tail call sequence.
96 This is not the same register as for normal calls on machines with
99 /* If REG was promoted from the actual mode of the argument expression,
100 indicates whether the promotion is sign- or zero-extended. */
102 /* Number of registers to use. 0 means put the whole arg in registers.
103 Also 0 if not passed in registers. */
105 /* Non-zero if argument must be passed on stack.
106 Note that some arguments may be passed on the stack
107 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
108 pass_on_stack identifies arguments that *cannot* go in registers. */
110 /* Offset of this argument from beginning of stack-args. */
111 struct args_size offset;
112 /* Similar, but offset to the start of the stack slot. Different from
113 OFFSET if this arg pads downward. */
114 struct args_size slot_offset;
115 /* Size of this argument on the stack, rounded up for any padding it gets,
116 parts of the argument passed in registers do not count.
117 If REG_PARM_STACK_SPACE is defined, then register parms
118 are counted here as well. */
119 struct args_size size;
120 /* Location on the stack at which parameter should be stored. The store
121 has already been done if STACK == VALUE. */
123 /* Location on the stack of the start of this argument slot. This can
124 differ from STACK if this arg pads downward. This location is known
125 to be aligned to FUNCTION_ARG_BOUNDARY. */
127 /* Place that this stack area has been saved, if needed. */
129 /* If an argument's alignment does not permit direct copying into registers,
130 copy in smaller-sized pieces into pseudos. These are stored in a
131 block pointed to by this field. The next field says how many
132 word-sized pseudos we made. */
135 /* The amount that the stack pointer needs to be adjusted to
136 force alignment for the next argument. */
137 struct args_size alignment_pad;
140 /* A vector of one char per byte of stack space. A byte if non-zero if
141 the corresponding stack location has been used.
142 This vector is used to prevent a function call within an argument from
143 clobbering any stack already set up. */
144 static char *stack_usage_map;
146 /* Size of STACK_USAGE_MAP. */
147 static int highest_outgoing_arg_in_use;
149 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
150 stack location's tail call argument has been already stored into the stack.
151 This bitmap is used to prevent sibling call optimization if function tries
152 to use parent's incoming argument slots when they have been already
153 overwritten with tail call arguments. */
154 static sbitmap stored_args_map;
156 /* stack_arg_under_construction is nonzero when an argument may be
157 initialized with a constructor call (including a C function that
158 returns a BLKmode struct) and expand_call must take special action
159 to make sure the object being constructed does not overlap the
160 argument list for the constructor call. */
161 int stack_arg_under_construction;
163 static int calls_function PARAMS ((tree, int));
164 static int calls_function_1 PARAMS ((tree, int));
166 /* Nonzero if this is a call to a `const' function. */
168 /* Nonzero if this is a call to a `volatile' function. */
169 #define ECF_NORETURN 2
170 /* Nonzero if this is a call to malloc or a related function. */
172 /* Nonzero if it is plausible that this is a call to alloca. */
173 #define ECF_MAY_BE_ALLOCA 8
174 /* Nonzero if this is a call to a function that won't throw an exception. */
175 #define ECF_NOTHROW 16
176 /* Nonzero if this is a call to setjmp or a related function. */
177 #define ECF_RETURNS_TWICE 32
178 /* Nonzero if this is a call to `longjmp'. */
179 #define ECF_LONGJMP 64
180 /* Nonzero if this is a syscall that makes a new process in the image of
182 #define ECF_FORK_OR_EXEC 128
183 #define ECF_SIBCALL 256
184 /* Nonzero if this is a call to "pure" function (like const function,
185 but may read memory. */
187 /* Nonzero if this is a call to a function that returns with the stack
188 pointer depressed. */
189 #define ECF_SP_DEPRESSED 1024
191 static void emit_call_1 PARAMS ((rtx, tree, tree, HOST_WIDE_INT,
192 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
193 rtx, int, rtx, int));
194 static void precompute_register_parameters PARAMS ((int,
197 static int store_one_arg PARAMS ((struct arg_data *, rtx, int, int,
199 static void store_unaligned_arguments_into_pseudos PARAMS ((struct arg_data *,
201 static int finalize_must_preallocate PARAMS ((int, int,
203 struct args_size *));
204 static void precompute_arguments PARAMS ((int, int,
206 static int compute_argument_block_size PARAMS ((int,
209 static void initialize_argument_information PARAMS ((int,
216 static void compute_argument_addresses PARAMS ((struct arg_data *,
218 static rtx rtx_for_function_call PARAMS ((tree, tree));
219 static void load_register_parameters PARAMS ((struct arg_data *,
221 static int libfunc_nothrow PARAMS ((rtx));
222 static rtx emit_library_call_value_1 PARAMS ((int, rtx, rtx, int,
225 static int special_function_p PARAMS ((tree, int));
226 static int flags_from_decl_or_type PARAMS ((tree));
227 static rtx try_to_integrate PARAMS ((tree, tree, rtx,
229 static int check_sibcall_argument_overlap_1 PARAMS ((rtx));
230 static int check_sibcall_argument_overlap PARAMS ((rtx, struct arg_data *));
232 static int combine_pending_stack_adjustment_and_call
233 PARAMS ((int, struct args_size *, int));
235 #ifdef REG_PARM_STACK_SPACE
236 static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
237 static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
240 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
243 If WHICH is 0, return 1 if EXP contains a call to any function.
244 Actually, we only need return 1 if evaluating EXP would require pushing
245 arguments on the stack, but that is too difficult to compute, so we just
246 assume any function call might require the stack. */
248 static tree calls_function_save_exprs;
251 calls_function (exp, which)
257 calls_function_save_exprs = 0;
258 val = calls_function_1 (exp, which);
259 calls_function_save_exprs = 0;
263 /* Recursive function to do the work of above function. */
266 calls_function_1 (exp, which)
271 enum tree_code code = TREE_CODE (exp);
272 int class = TREE_CODE_CLASS (code);
273 int length = first_rtl_op (code);
275 /* If this code is language-specific, we don't know what it will do. */
276 if ((int) code >= NUM_TREE_CODES)
284 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
286 && (TYPE_RETURNS_STACK_DEPRESSED
287 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))))
289 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
290 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
292 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
294 & ECF_MAY_BE_ALLOCA))
300 if (SAVE_EXPR_RTL (exp) != 0)
302 if (value_member (exp, calls_function_save_exprs))
304 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
305 calls_function_save_exprs);
306 return (TREE_OPERAND (exp, 0) != 0
307 && calls_function_1 (TREE_OPERAND (exp, 0), which));
312 register tree subblock;
314 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
315 if (DECL_INITIAL (local) != 0
316 && calls_function_1 (DECL_INITIAL (local), which))
319 for (subblock = BLOCK_SUBBLOCKS (exp);
321 subblock = TREE_CHAIN (subblock))
322 if (calls_function_1 (subblock, which))
328 for (; exp != 0; exp = TREE_CHAIN (exp))
329 if (calls_function_1 (TREE_VALUE (exp), which))
337 /* Only expressions, references, and blocks can contain calls. */
338 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
341 for (i = 0; i < length; i++)
342 if (TREE_OPERAND (exp, i) != 0
343 && calls_function_1 (TREE_OPERAND (exp, i), which))
349 /* Force FUNEXP into a form suitable for the address of a CALL,
350 and return that as an rtx. Also load the static chain register
351 if FNDECL is a nested function.
353 CALL_FUSAGE points to a variable holding the prospective
354 CALL_INSN_FUNCTION_USAGE information. */
357 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen)
363 rtx static_chain_value = 0;
365 funexp = protect_from_queue (funexp, 0);
368 /* Get possible static chain value for nested function in C. */
369 static_chain_value = lookup_static_chain (fndecl);
371 /* Make a valid memory address and copy constants thru pseudo-regs,
372 but not for a constant address if -fno-function-cse. */
373 if (GET_CODE (funexp) != SYMBOL_REF)
374 /* If we are using registers for parameters, force the
375 function address into a register now. */
376 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
377 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
378 : memory_address (FUNCTION_MODE, funexp));
381 #ifndef NO_FUNCTION_CSE
382 if (optimize && ! flag_no_function_cse)
383 #ifdef NO_RECURSIVE_FUNCTION_CSE
384 if (fndecl != current_function_decl)
386 funexp = force_reg (Pmode, funexp);
390 if (static_chain_value != 0)
392 emit_move_insn (static_chain_rtx, static_chain_value);
394 if (GET_CODE (static_chain_rtx) == REG)
395 use_reg (call_fusage, static_chain_rtx);
401 /* Generate instructions to call function FUNEXP,
402 and optionally pop the results.
403 The CALL_INSN is the first insn generated.
405 FNDECL is the declaration node of the function. This is given to the
406 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
408 FUNTYPE is the data type of the function. This is given to the macro
409 RETURN_POPS_ARGS to determine whether this function pops its own args.
410 We used to allow an identifier for library functions, but that doesn't
411 work when the return type is an aggregate type and the calling convention
412 says that the pointer to this aggregate is to be popped by the callee.
414 STACK_SIZE is the number of bytes of arguments on the stack,
415 ROUNDED_STACK_SIZE is that number rounded up to
416 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
417 both to put into the call insn and to generate explicit popping
420 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
421 It is zero if this call doesn't want a structure value.
423 NEXT_ARG_REG is the rtx that results from executing
424 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
425 just after all the args have had their registers assigned.
426 This could be whatever you like, but normally it is the first
427 arg-register beyond those used for args in this call,
428 or 0 if all the arg-registers are used in this call.
429 It is passed on to `gen_call' so you can put this info in the call insn.
431 VALREG is a hard register in which a value is returned,
432 or 0 if the call does not return a value.
434 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
435 the args to this call were processed.
436 We restore `inhibit_defer_pop' to that value.
438 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
439 denote registers used by the called function. */
442 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
443 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
444 call_fusage, ecf_flags)
446 tree fndecl ATTRIBUTE_UNUSED;
447 tree funtype ATTRIBUTE_UNUSED;
448 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
449 HOST_WIDE_INT rounded_stack_size;
450 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
453 int old_inhibit_defer_pop;
457 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
459 int already_popped = 0;
460 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
461 #if defined (HAVE_call) && defined (HAVE_call_value)
462 rtx struct_value_size_rtx;
463 struct_value_size_rtx = GEN_INT (struct_value_size);
466 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
467 and we don't want to load it into a register as an optimization,
468 because prepare_call_address already did it if it should be done. */
469 if (GET_CODE (funexp) != SYMBOL_REF)
470 funexp = memory_address (FUNCTION_MODE, funexp);
472 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
473 if ((ecf_flags & ECF_SIBCALL)
474 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
475 && (RETURN_POPS_ARGS (fndecl, funtype, stack_size) > 0
478 rtx n_pop = GEN_INT (RETURN_POPS_ARGS (fndecl, funtype, stack_size));
481 /* If this subroutine pops its own args, record that in the call insn
482 if possible, for the sake of frame pointer elimination. */
485 pat = GEN_SIBCALL_VALUE_POP (valreg,
486 gen_rtx_MEM (FUNCTION_MODE, funexp),
487 rounded_stack_size_rtx, next_arg_reg,
490 pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
491 rounded_stack_size_rtx, next_arg_reg, n_pop);
493 emit_call_insn (pat);
499 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
500 /* If the target has "call" or "call_value" insns, then prefer them
501 if no arguments are actually popped. If the target does not have
502 "call" or "call_value" insns, then we must use the popping versions
503 even if the call has no arguments to pop. */
504 #if defined (HAVE_call) && defined (HAVE_call_value)
505 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
506 && n_popped > 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
508 if (HAVE_call_pop && HAVE_call_value_pop)
511 rtx n_pop = GEN_INT (n_popped);
514 /* If this subroutine pops its own args, record that in the call insn
515 if possible, for the sake of frame pointer elimination. */
518 pat = GEN_CALL_VALUE_POP (valreg,
519 gen_rtx_MEM (FUNCTION_MODE, funexp),
520 rounded_stack_size_rtx, next_arg_reg, n_pop);
522 pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
523 rounded_stack_size_rtx, next_arg_reg, n_pop);
525 emit_call_insn (pat);
531 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
532 if ((ecf_flags & ECF_SIBCALL)
533 && HAVE_sibcall && HAVE_sibcall_value)
536 emit_call_insn (GEN_SIBCALL_VALUE (valreg,
537 gen_rtx_MEM (FUNCTION_MODE, funexp),
538 rounded_stack_size_rtx,
539 next_arg_reg, NULL_RTX));
541 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
542 rounded_stack_size_rtx, next_arg_reg,
543 struct_value_size_rtx));
548 #if defined (HAVE_call) && defined (HAVE_call_value)
549 if (HAVE_call && HAVE_call_value)
552 emit_call_insn (GEN_CALL_VALUE (valreg,
553 gen_rtx_MEM (FUNCTION_MODE, funexp),
554 rounded_stack_size_rtx, next_arg_reg,
557 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
558 rounded_stack_size_rtx, next_arg_reg,
559 struct_value_size_rtx));
565 /* Find the CALL insn we just emitted. */
566 for (call_insn = get_last_insn ();
567 call_insn && GET_CODE (call_insn) != CALL_INSN;
568 call_insn = PREV_INSN (call_insn))
574 /* Mark memory as used for "pure" function call. */
575 if (ecf_flags & ECF_PURE)
577 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
578 gen_rtx_USE (VOIDmode,
579 gen_rtx_MEM (BLKmode,
580 gen_rtx_SCRATCH (VOIDmode))), call_fusage);
583 /* Put the register usage information on the CALL. If there is already
584 some usage information, put ours at the end. */
585 if (CALL_INSN_FUNCTION_USAGE (call_insn))
589 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
590 link = XEXP (link, 1))
593 XEXP (link, 1) = call_fusage;
596 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
598 /* If this is a const call, then set the insn's unchanging bit. */
599 if (ecf_flags & (ECF_CONST | ECF_PURE))
600 CONST_CALL_P (call_insn) = 1;
602 /* If this call can't throw, attach a REG_EH_REGION reg note to that
604 if (ecf_flags & ECF_NOTHROW)
605 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
606 REG_NOTES (call_insn));
608 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
610 /* Restore this now, so that we do defer pops for this call's args
611 if the context of the call as a whole permits. */
612 inhibit_defer_pop = old_inhibit_defer_pop;
617 CALL_INSN_FUNCTION_USAGE (call_insn)
618 = gen_rtx_EXPR_LIST (VOIDmode,
619 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
620 CALL_INSN_FUNCTION_USAGE (call_insn));
621 rounded_stack_size -= n_popped;
622 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
623 stack_pointer_delta -= n_popped;
626 if (!ACCUMULATE_OUTGOING_ARGS)
628 /* If returning from the subroutine does not automatically pop the args,
629 we need an instruction to pop them sooner or later.
630 Perhaps do it now; perhaps just record how much space to pop later.
632 If returning from the subroutine does pop the args, indicate that the
633 stack pointer will be changed. */
635 if (rounded_stack_size != 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
637 if (flag_defer_pop && inhibit_defer_pop == 0
638 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
639 pending_stack_adjust += rounded_stack_size;
641 adjust_stack (rounded_stack_size_rtx);
644 /* When we accumulate outgoing args, we must avoid any stack manipulations.
645 Restore the stack pointer to its original value now. Usually
646 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
647 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
648 popping variants of functions exist as well.
650 ??? We may optimize similar to defer_pop above, but it is
651 probably not worthwhile.
653 ??? It will be worthwhile to enable combine_stack_adjustments even for
656 anti_adjust_stack (GEN_INT (n_popped));
659 /* Determine if the function identified by NAME and FNDECL is one with
660 special properties we wish to know about.
662 For example, if the function might return more than one time (setjmp), then
663 set RETURNS_TWICE to a nonzero value.
665 Similarly set LONGJMP for if the function is in the longjmp family.
667 Set MALLOC for any of the standard memory allocation functions which
668 allocate from the heap.
670 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
671 space from the stack such as alloca. */
674 special_function_p (fndecl, flags)
678 if (! (flags & ECF_MALLOC)
679 && fndecl && DECL_NAME (fndecl)
680 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
681 /* Exclude functions not at the file scope, or not `extern',
682 since they are not the magic functions we would otherwise
684 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
686 char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
689 /* We assume that alloca will always be called by name. It
690 makes no sense to pass it as a pointer-to-function to
691 anything that does not understand its behavior. */
692 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
694 && ! strcmp (name, "alloca"))
695 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
697 && ! strcmp (name, "__builtin_alloca"))))
698 flags |= ECF_MAY_BE_ALLOCA;
700 /* Disregard prefix _, __ or __x. */
703 if (name[1] == '_' && name[2] == 'x')
705 else if (name[1] == '_')
714 && (! strcmp (tname, "setjmp")
715 || ! strcmp (tname, "setjmp_syscall")))
717 && ! strcmp (tname, "sigsetjmp"))
719 && ! strcmp (tname, "savectx")))
720 flags |= ECF_RETURNS_TWICE;
723 && ! strcmp (tname, "siglongjmp"))
724 flags |= ECF_LONGJMP;
726 else if ((tname[0] == 'q' && tname[1] == 's'
727 && ! strcmp (tname, "qsetjmp"))
728 || (tname[0] == 'v' && tname[1] == 'f'
729 && ! strcmp (tname, "vfork")))
730 flags |= ECF_RETURNS_TWICE;
732 else if (tname[0] == 'l' && tname[1] == 'o'
733 && ! strcmp (tname, "longjmp"))
734 flags |= ECF_LONGJMP;
736 else if ((tname[0] == 'f' && tname[1] == 'o'
737 && ! strcmp (tname, "fork"))
738 /* Linux specific: __clone. check NAME to insist on the
739 leading underscores, to avoid polluting the ISO / POSIX
741 || (name[0] == '_' && name[1] == '_'
742 && ! strcmp (tname, "clone"))
743 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
744 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
746 || ((tname[5] == 'p' || tname[5] == 'e')
747 && tname[6] == '\0'))))
748 flags |= ECF_FORK_OR_EXEC;
750 /* Do not add any more malloc-like functions to this list,
751 instead mark them as malloc functions using the malloc attribute.
752 Note, realloc is not suitable for attribute malloc since
753 it may return the same address across multiple calls.
754 C++ operator new is not suitable because it is not required
755 to return a unique pointer; indeed, the standard placement new
756 just returns its argument. */
757 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl))) == Pmode
758 && (! strcmp (tname, "malloc")
759 || ! strcmp (tname, "calloc")
760 || ! strcmp (tname, "strdup")))
766 /* Return nonzero when tree represent call to longjmp. */
769 setjmp_call_p (fndecl)
772 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
775 /* Detect flags (function attributes) from the function type node. */
778 flags_from_decl_or_type (exp)
783 /* ??? We can't set IS_MALLOC for function types? */
786 /* The function exp may have the `malloc' attribute. */
787 if (DECL_P (exp) && DECL_IS_MALLOC (exp))
790 /* The function exp may have the `pure' attribute. */
791 if (DECL_P (exp) && DECL_IS_PURE (exp))
794 if (TREE_NOTHROW (exp))
795 flags |= ECF_NOTHROW;
798 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
801 if (TREE_THIS_VOLATILE (exp))
802 flags |= ECF_NORETURN;
808 /* Precompute all register parameters as described by ARGS, storing values
809 into fields within the ARGS array.
811 NUM_ACTUALS indicates the total number elements in the ARGS array.
813 Set REG_PARM_SEEN if we encounter a register parameter. */
816 precompute_register_parameters (num_actuals, args, reg_parm_seen)
818 struct arg_data *args;
825 for (i = 0; i < num_actuals; i++)
826 if (args[i].reg != 0 && ! args[i].pass_on_stack)
830 if (args[i].value == 0)
833 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
835 preserve_temp_slots (args[i].value);
838 /* ANSI doesn't require a sequence point here,
839 but PCC has one, so this will avoid some problems. */
843 /* If we are to promote the function arg to a wider mode,
846 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
848 = convert_modes (args[i].mode,
849 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
850 args[i].value, args[i].unsignedp);
852 /* If the value is expensive, and we are inside an appropriately
853 short loop, put the value into a pseudo and then put the pseudo
856 For small register classes, also do this if this call uses
857 register parameters. This is to avoid reload conflicts while
858 loading the parameters registers. */
860 if ((! (GET_CODE (args[i].value) == REG
861 || (GET_CODE (args[i].value) == SUBREG
862 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
863 && args[i].mode != BLKmode
864 && rtx_cost (args[i].value, SET) > 2
865 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
866 || preserve_subexpressions_p ()))
867 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
871 #ifdef REG_PARM_STACK_SPACE
873 /* The argument list is the property of the called routine and it
874 may clobber it. If the fixed area has been used for previous
875 parameters, we must save and restore it. */
878 save_fixed_argument_area (reg_parm_stack_space, argblock,
879 low_to_save, high_to_save)
880 int reg_parm_stack_space;
886 rtx save_area = NULL_RTX;
888 /* Compute the boundary of the that needs to be saved, if any. */
889 #ifdef ARGS_GROW_DOWNWARD
890 for (i = 0; i < reg_parm_stack_space + 1; i++)
892 for (i = 0; i < reg_parm_stack_space; i++)
895 if (i >= highest_outgoing_arg_in_use
896 || stack_usage_map[i] == 0)
899 if (*low_to_save == -1)
905 if (*low_to_save >= 0)
907 int num_to_save = *high_to_save - *low_to_save + 1;
908 enum machine_mode save_mode
909 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
912 /* If we don't have the required alignment, must do this in BLKmode. */
913 if ((*low_to_save & (MIN (GET_MODE_SIZE (save_mode),
914 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
917 #ifdef ARGS_GROW_DOWNWARD
919 = gen_rtx_MEM (save_mode,
920 memory_address (save_mode,
921 plus_constant (argblock,
924 stack_area = gen_rtx_MEM (save_mode,
925 memory_address (save_mode,
926 plus_constant (argblock,
929 if (save_mode == BLKmode)
931 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
932 /* Cannot use emit_block_move here because it can be done by a
933 library call which in turn gets into this place again and deadly
934 infinite recursion happens. */
935 move_by_pieces (validize_mem (save_area), stack_area, num_to_save,
940 save_area = gen_reg_rtx (save_mode);
941 emit_move_insn (save_area, stack_area);
948 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
954 enum machine_mode save_mode = GET_MODE (save_area);
955 #ifdef ARGS_GROW_DOWNWARD
957 = gen_rtx_MEM (save_mode,
958 memory_address (save_mode,
959 plus_constant (argblock,
963 = gen_rtx_MEM (save_mode,
964 memory_address (save_mode,
965 plus_constant (argblock,
969 if (save_mode != BLKmode)
970 emit_move_insn (stack_area, save_area);
972 /* Cannot use emit_block_move here because it can be done by a library
973 call which in turn gets into this place again and deadly infinite
974 recursion happens. */
975 move_by_pieces (stack_area, validize_mem (save_area),
976 high_to_save - low_to_save + 1, PARM_BOUNDARY);
980 /* If any elements in ARGS refer to parameters that are to be passed in
981 registers, but not in memory, and whose alignment does not permit a
982 direct copy into registers. Copy the values into a group of pseudos
983 which we will later copy into the appropriate hard registers.
985 Pseudos for each unaligned argument will be stored into the array
986 args[argnum].aligned_regs. The caller is responsible for deallocating
987 the aligned_regs array if it is nonzero. */
990 store_unaligned_arguments_into_pseudos (args, num_actuals)
991 struct arg_data *args;
996 for (i = 0; i < num_actuals; i++)
997 if (args[i].reg != 0 && ! args[i].pass_on_stack
998 && args[i].mode == BLKmode
999 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1000 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1002 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1003 int big_endian_correction = 0;
1005 args[i].n_aligned_regs
1006 = args[i].partial ? args[i].partial
1007 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1009 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
1010 * args[i].n_aligned_regs);
1012 /* Structures smaller than a word are aligned to the least
1013 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1014 this means we must skip the empty high order bytes when
1015 calculating the bit offset. */
1016 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
1017 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1019 for (j = 0; j < args[i].n_aligned_regs; j++)
1021 rtx reg = gen_reg_rtx (word_mode);
1022 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1023 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1024 int bitalign = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
1026 args[i].aligned_regs[j] = reg;
1028 /* There is no need to restrict this code to loading items
1029 in TYPE_ALIGN sized hunks. The bitfield instructions can
1030 load up entire word sized registers efficiently.
1032 ??? This may not be needed anymore.
1033 We use to emit a clobber here but that doesn't let later
1034 passes optimize the instructions we emit. By storing 0 into
1035 the register later passes know the first AND to zero out the
1036 bitfield being set in the register is unnecessary. The store
1037 of 0 will be deleted as will at least the first AND. */
1039 emit_move_insn (reg, const0_rtx);
1041 bytes -= bitsize / BITS_PER_UNIT;
1042 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
1043 extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1044 word_mode, word_mode, bitalign,
1046 bitalign, BITS_PER_WORD);
1051 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1054 NUM_ACTUALS is the total number of parameters.
1056 N_NAMED_ARGS is the total number of named arguments.
1058 FNDECL is the tree code for the target of this call (if known)
1060 ARGS_SO_FAR holds state needed by the target to know where to place
1063 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1064 for arguments which are passed in registers.
1066 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1067 and may be modified by this routine.
1069 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1070 flags which may may be modified by this routine. */
1073 initialize_argument_information (num_actuals, args, args_size, n_named_args,
1074 actparms, fndecl, args_so_far,
1075 reg_parm_stack_space, old_stack_level,
1076 old_pending_adj, must_preallocate,
1078 int num_actuals ATTRIBUTE_UNUSED;
1079 struct arg_data *args;
1080 struct args_size *args_size;
1081 int n_named_args ATTRIBUTE_UNUSED;
1084 CUMULATIVE_ARGS *args_so_far;
1085 int reg_parm_stack_space;
1086 rtx *old_stack_level;
1087 int *old_pending_adj;
1088 int *must_preallocate;
1091 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1094 /* Count arg position in order args appear. */
1097 struct args_size alignment_pad;
1101 args_size->constant = 0;
1104 /* In this loop, we consider args in the order they are written.
1105 We fill up ARGS from the front or from the back if necessary
1106 so that in any case the first arg to be pushed ends up at the front. */
1108 if (PUSH_ARGS_REVERSED)
1110 i = num_actuals - 1, inc = -1;
1111 /* In this case, must reverse order of args
1112 so that we compute and push the last arg first. */
1119 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1120 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1122 tree type = TREE_TYPE (TREE_VALUE (p));
1124 enum machine_mode mode;
1126 args[i].tree_value = TREE_VALUE (p);
1128 /* Replace erroneous argument with constant zero. */
1129 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1130 args[i].tree_value = integer_zero_node, type = integer_type_node;
1132 /* If TYPE is a transparent union, pass things the way we would
1133 pass the first field of the union. We have already verified that
1134 the modes are the same. */
1135 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1136 type = TREE_TYPE (TYPE_FIELDS (type));
1138 /* Decide where to pass this arg.
1140 args[i].reg is nonzero if all or part is passed in registers.
1142 args[i].partial is nonzero if part but not all is passed in registers,
1143 and the exact value says how many words are passed in registers.
1145 args[i].pass_on_stack is nonzero if the argument must at least be
1146 computed on the stack. It may then be loaded back into registers
1147 if args[i].reg is nonzero.
1149 These decisions are driven by the FUNCTION_... macros and must agree
1150 with those made by function.c. */
1152 /* See if this argument should be passed by invisible reference. */
1153 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1154 && contains_placeholder_p (TYPE_SIZE (type)))
1155 || TREE_ADDRESSABLE (type)
1156 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1157 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1158 type, argpos < n_named_args)
1162 /* If we're compiling a thunk, pass through invisible
1163 references instead of making a copy. */
1164 if (current_function_is_thunk
1165 #ifdef FUNCTION_ARG_CALLEE_COPIES
1166 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1167 type, argpos < n_named_args)
1168 /* If it's in a register, we must make a copy of it too. */
1169 /* ??? Is this a sufficient test? Is there a better one? */
1170 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1171 && REG_P (DECL_RTL (args[i].tree_value)))
1172 && ! TREE_ADDRESSABLE (type))
1176 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1177 new object from the argument. If we are passing by
1178 invisible reference, the callee will do that for us, so we
1179 can strip off the TARGET_EXPR. This is not always safe,
1180 but it is safe in the only case where this is a useful
1181 optimization; namely, when the argument is a plain object.
1182 In that case, the frontend is just asking the backend to
1183 make a bitwise copy of the argument. */
1185 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1186 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1187 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1188 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1190 args[i].tree_value = build1 (ADDR_EXPR,
1191 build_pointer_type (type),
1192 args[i].tree_value);
1193 type = build_pointer_type (type);
1197 /* We make a copy of the object and pass the address to the
1198 function being called. */
1201 if (!COMPLETE_TYPE_P (type)
1202 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1203 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1204 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1205 STACK_CHECK_MAX_VAR_SIZE))))
1207 /* This is a variable-sized object. Make space on the stack
1209 rtx size_rtx = expr_size (TREE_VALUE (p));
1211 if (*old_stack_level == 0)
1213 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1214 *old_pending_adj = pending_stack_adjust;
1215 pending_stack_adjust = 0;
1218 copy = gen_rtx_MEM (BLKmode,
1219 allocate_dynamic_stack_space
1220 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1221 set_mem_attributes (copy, type, 1);
1224 copy = assign_temp (type, 0, 1, 0);
1226 store_expr (args[i].tree_value, copy, 0);
1227 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1229 args[i].tree_value = build1 (ADDR_EXPR,
1230 build_pointer_type (type),
1231 make_tree (type, copy));
1232 type = build_pointer_type (type);
1236 mode = TYPE_MODE (type);
1237 unsignedp = TREE_UNSIGNED (type);
1239 #ifdef PROMOTE_FUNCTION_ARGS
1240 mode = promote_mode (type, mode, &unsignedp, 1);
1243 args[i].unsignedp = unsignedp;
1244 args[i].mode = mode;
1246 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1247 argpos < n_named_args);
1248 #ifdef FUNCTION_INCOMING_ARG
1249 /* If this is a sibling call and the machine has register windows, the
1250 register window has to be unwinded before calling the routine, so
1251 arguments have to go into the incoming registers. */
1252 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1253 argpos < n_named_args);
1255 args[i].tail_call_reg = args[i].reg;
1258 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1261 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1262 argpos < n_named_args);
1265 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1267 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1268 it means that we are to pass this arg in the register(s) designated
1269 by the PARALLEL, but also to pass it in the stack. */
1270 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1271 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1272 args[i].pass_on_stack = 1;
1274 /* If this is an addressable type, we must preallocate the stack
1275 since we must evaluate the object into its final location.
1277 If this is to be passed in both registers and the stack, it is simpler
1279 if (TREE_ADDRESSABLE (type)
1280 || (args[i].pass_on_stack && args[i].reg != 0))
1281 *must_preallocate = 1;
1283 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1284 we cannot consider this function call constant. */
1285 if (TREE_ADDRESSABLE (type))
1286 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1288 /* Compute the stack-size of this argument. */
1289 if (args[i].reg == 0 || args[i].partial != 0
1290 || reg_parm_stack_space > 0
1291 || args[i].pass_on_stack)
1292 locate_and_pad_parm (mode, type,
1293 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1298 fndecl, args_size, &args[i].offset,
1299 &args[i].size, &alignment_pad);
1301 #ifndef ARGS_GROW_DOWNWARD
1302 args[i].slot_offset = *args_size;
1305 args[i].alignment_pad = alignment_pad;
1307 /* If a part of the arg was put into registers,
1308 don't include that part in the amount pushed. */
1309 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1310 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1311 / (PARM_BOUNDARY / BITS_PER_UNIT)
1312 * (PARM_BOUNDARY / BITS_PER_UNIT));
1314 /* Update ARGS_SIZE, the total stack space for args so far. */
1316 args_size->constant += args[i].size.constant;
1317 if (args[i].size.var)
1319 ADD_PARM_SIZE (*args_size, args[i].size.var);
1322 /* Since the slot offset points to the bottom of the slot,
1323 we must record it after incrementing if the args grow down. */
1324 #ifdef ARGS_GROW_DOWNWARD
1325 args[i].slot_offset = *args_size;
1327 args[i].slot_offset.constant = -args_size->constant;
1329 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1332 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1333 have been used, etc. */
1335 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1336 argpos < n_named_args);
1340 /* Update ARGS_SIZE to contain the total size for the argument block.
1341 Return the original constant component of the argument block's size.
1343 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1344 for arguments passed in registers. */
1347 compute_argument_block_size (reg_parm_stack_space, args_size,
1348 preferred_stack_boundary)
1349 int reg_parm_stack_space;
1350 struct args_size *args_size;
1351 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1353 int unadjusted_args_size = args_size->constant;
1355 /* For accumulate outgoing args mode we don't need to align, since the frame
1356 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1357 backends from generating missaligned frame sizes. */
1358 #ifdef STACK_BOUNDARY
1359 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1360 preferred_stack_boundary = STACK_BOUNDARY;
1363 /* Compute the actual size of the argument block required. The variable
1364 and constant sizes must be combined, the size may have to be rounded,
1365 and there may be a minimum required size. */
1369 args_size->var = ARGS_SIZE_TREE (*args_size);
1370 args_size->constant = 0;
1372 #ifdef PREFERRED_STACK_BOUNDARY
1373 preferred_stack_boundary /= BITS_PER_UNIT;
1374 if (preferred_stack_boundary > 1)
1376 /* We don't handle this case yet. To handle it correctly we have
1377 to add the delta, round and substract the delta.
1378 Currently no machine description requires this support. */
1379 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1381 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1385 if (reg_parm_stack_space > 0)
1388 = size_binop (MAX_EXPR, args_size->var,
1389 ssize_int (reg_parm_stack_space));
1391 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1392 /* The area corresponding to register parameters is not to count in
1393 the size of the block we need. So make the adjustment. */
1395 = size_binop (MINUS_EXPR, args_size->var,
1396 ssize_int (reg_parm_stack_space));
1402 #ifdef PREFERRED_STACK_BOUNDARY
1403 preferred_stack_boundary /= BITS_PER_UNIT;
1404 if (preferred_stack_boundary < 1)
1405 preferred_stack_boundary = 1;
1406 args_size->constant = (((args_size->constant
1407 + stack_pointer_delta
1408 + preferred_stack_boundary - 1)
1409 / preferred_stack_boundary
1410 * preferred_stack_boundary)
1411 - stack_pointer_delta);
1414 args_size->constant = MAX (args_size->constant,
1415 reg_parm_stack_space);
1417 #ifdef MAYBE_REG_PARM_STACK_SPACE
1418 if (reg_parm_stack_space == 0)
1419 args_size->constant = 0;
1422 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1423 args_size->constant -= reg_parm_stack_space;
1426 return unadjusted_args_size;
1429 /* Precompute parameters as needed for a function call.
1431 FLAGS is mask of ECF_* constants.
1433 NUM_ACTUALS is the number of arguments.
1435 ARGS is an array containing information for each argument; this routine
1436 fills in the INITIAL_VALUE and VALUE fields for each precomputed argument.
1440 precompute_arguments (flags, num_actuals, args)
1443 struct arg_data *args;
1447 /* If this function call is cse'able, precompute all the parameters.
1448 Note that if the parameter is constructed into a temporary, this will
1449 cause an additional copy because the parameter will be constructed
1450 into a temporary location and then copied into the outgoing arguments.
1451 If a parameter contains a call to alloca and this function uses the
1452 stack, precompute the parameter. */
1454 /* If we preallocated the stack space, and some arguments must be passed
1455 on the stack, then we must precompute any parameter which contains a
1456 function call which will store arguments on the stack.
1457 Otherwise, evaluating the parameter may clobber previous parameters
1458 which have already been stored into the stack. (we have code to avoid
1459 such case by saving the ougoing stack arguments, but it results in
1462 for (i = 0; i < num_actuals; i++)
1463 if ((flags & (ECF_CONST | ECF_PURE))
1464 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1466 /* If this is an addressable type, we cannot pre-evaluate it. */
1467 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1473 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1475 preserve_temp_slots (args[i].value);
1478 /* ANSI doesn't require a sequence point here,
1479 but PCC has one, so this will avoid some problems. */
1482 args[i].initial_value = args[i].value
1483 = protect_from_queue (args[i].value, 0);
1485 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) != args[i].mode)
1488 = convert_modes (args[i].mode,
1489 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1490 args[i].value, args[i].unsignedp);
1491 #ifdef PROMOTE_FOR_CALL_ONLY
1492 /* CSE will replace this only if it contains args[i].value
1493 pseudo, so convert it down to the declared mode using
1495 if (GET_CODE (args[i].value) == REG
1496 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1498 args[i].initial_value
1499 = gen_rtx_SUBREG (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1501 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1502 SUBREG_PROMOTED_UNSIGNED_P (args[i].initial_value)
1503 = args[i].unsignedp;
1510 /* Given the current state of MUST_PREALLOCATE and information about
1511 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1512 compute and return the final value for MUST_PREALLOCATE. */
1515 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1516 int must_preallocate;
1518 struct arg_data *args;
1519 struct args_size *args_size;
1521 /* See if we have or want to preallocate stack space.
1523 If we would have to push a partially-in-regs parm
1524 before other stack parms, preallocate stack space instead.
1526 If the size of some parm is not a multiple of the required stack
1527 alignment, we must preallocate.
1529 If the total size of arguments that would otherwise create a copy in
1530 a temporary (such as a CALL) is more than half the total argument list
1531 size, preallocation is faster.
1533 Another reason to preallocate is if we have a machine (like the m88k)
1534 where stack alignment is required to be maintained between every
1535 pair of insns, not just when the call is made. However, we assume here
1536 that such machines either do not have push insns (and hence preallocation
1537 would occur anyway) or the problem is taken care of with
1540 if (! must_preallocate)
1542 int partial_seen = 0;
1543 int copy_to_evaluate_size = 0;
1546 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1548 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1550 else if (partial_seen && args[i].reg == 0)
1551 must_preallocate = 1;
1553 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1554 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1555 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1556 || TREE_CODE (args[i].tree_value) == COND_EXPR
1557 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1558 copy_to_evaluate_size
1559 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1562 if (copy_to_evaluate_size * 2 >= args_size->constant
1563 && args_size->constant > 0)
1564 must_preallocate = 1;
1566 return must_preallocate;
1569 /* If we preallocated stack space, compute the address of each argument
1570 and store it into the ARGS array.
1572 We need not ensure it is a valid memory address here; it will be
1573 validized when it is used.
1575 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1578 compute_argument_addresses (args, argblock, num_actuals)
1579 struct arg_data *args;
1585 rtx arg_reg = argblock;
1586 int i, arg_offset = 0;
1588 if (GET_CODE (argblock) == PLUS)
1589 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1591 for (i = 0; i < num_actuals; i++)
1593 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1594 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1597 /* Skip this parm if it will not be passed on the stack. */
1598 if (! args[i].pass_on_stack && args[i].reg != 0)
1601 if (GET_CODE (offset) == CONST_INT)
1602 addr = plus_constant (arg_reg, INTVAL (offset));
1604 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1606 addr = plus_constant (addr, arg_offset);
1607 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1608 set_mem_attributes (args[i].stack,
1609 TREE_TYPE (args[i].tree_value), 1);
1611 if (GET_CODE (slot_offset) == CONST_INT)
1612 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1614 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1616 addr = plus_constant (addr, arg_offset);
1617 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1618 set_mem_attributes (args[i].stack_slot,
1619 TREE_TYPE (args[i].tree_value), 1);
1621 /* Function incoming arguments may overlap with sibling call
1622 outgoing arguments and we cannot allow reordering of reads
1623 from function arguments with stores to outgoing arguments
1624 of sibling calls. */
1625 MEM_ALIAS_SET (args[i].stack) = 0;
1626 MEM_ALIAS_SET (args[i].stack_slot) = 0;
1631 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1632 in a call instruction.
1634 FNDECL is the tree node for the target function. For an indirect call
1635 FNDECL will be NULL_TREE.
1637 EXP is the CALL_EXPR for this call. */
1640 rtx_for_function_call (fndecl, exp)
1646 /* Get the function to call, in the form of RTL. */
1649 /* If this is the first use of the function, see if we need to
1650 make an external definition for it. */
1651 if (! TREE_USED (fndecl))
1653 assemble_external (fndecl);
1654 TREE_USED (fndecl) = 1;
1657 /* Get a SYMBOL_REF rtx for the function address. */
1658 funexp = XEXP (DECL_RTL (fndecl), 0);
1661 /* Generate an rtx (probably a pseudo-register) for the address. */
1666 expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1667 pop_temp_slots (); /* FUNEXP can't be BLKmode */
1669 /* Check the function is executable. */
1670 if (current_function_check_memory_usage)
1672 #ifdef POINTERS_EXTEND_UNSIGNED
1673 /* It might be OK to convert funexp in place, but there's
1674 a lot going on between here and when it happens naturally
1675 that this seems safer. */
1676 funaddr = convert_memory_address (Pmode, funexp);
1678 emit_library_call (chkr_check_exec_libfunc, 1,
1687 /* Do the register loads required for any wholly-register parms or any
1688 parms which are passed both on the stack and in a register. Their
1689 expressions were already evaluated.
1691 Mark all register-parms as living through the call, putting these USE
1692 insns in the CALL_INSN_FUNCTION_USAGE field. */
1695 load_register_parameters (args, num_actuals, call_fusage, flags)
1696 struct arg_data *args;
1703 #ifdef LOAD_ARGS_REVERSED
1704 for (i = num_actuals - 1; i >= 0; i--)
1706 for (i = 0; i < num_actuals; i++)
1709 rtx reg = ((flags & ECF_SIBCALL)
1710 ? args[i].tail_call_reg : args[i].reg);
1711 int partial = args[i].partial;
1716 /* Set to non-negative if must move a word at a time, even if just
1717 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1718 we just use a normal move insn. This value can be zero if the
1719 argument is a zero size structure with no fields. */
1720 nregs = (partial ? partial
1721 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1722 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1723 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1726 /* Handle calls that pass values in multiple non-contiguous
1727 locations. The Irix 6 ABI has examples of this. */
1729 if (GET_CODE (reg) == PARALLEL)
1730 emit_group_load (reg, args[i].value,
1731 int_size_in_bytes (TREE_TYPE (args[i].tree_value)),
1732 TYPE_ALIGN (TREE_TYPE (args[i].tree_value)));
1734 /* If simple case, just do move. If normal partial, store_one_arg
1735 has already loaded the register for us. In all other cases,
1736 load the register(s) from memory. */
1738 else if (nregs == -1)
1739 emit_move_insn (reg, args[i].value);
1741 /* If we have pre-computed the values to put in the registers in
1742 the case of non-aligned structures, copy them in now. */
1744 else if (args[i].n_aligned_regs != 0)
1745 for (j = 0; j < args[i].n_aligned_regs; j++)
1746 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1747 args[i].aligned_regs[j]);
1749 else if (partial == 0 || args[i].pass_on_stack)
1750 move_block_to_reg (REGNO (reg),
1751 validize_mem (args[i].value), nregs,
1754 /* Handle calls that pass values in multiple non-contiguous
1755 locations. The Irix 6 ABI has examples of this. */
1756 if (GET_CODE (reg) == PARALLEL)
1757 use_group_regs (call_fusage, reg);
1758 else if (nregs == -1)
1759 use_reg (call_fusage, reg);
1761 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1766 /* Try to integrate function. See expand_inline_function for documentation
1767 about the parameters. */
1770 try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1776 rtx structure_value_addr;
1781 rtx old_stack_level = 0;
1782 int reg_parm_stack_space = 0;
1784 #ifdef REG_PARM_STACK_SPACE
1785 #ifdef MAYBE_REG_PARM_STACK_SPACE
1786 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1788 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1792 before_call = get_last_insn ();
1794 timevar_push (TV_INTEGRATION);
1796 temp = expand_inline_function (fndecl, actparms, target,
1798 structure_value_addr);
1800 timevar_pop (TV_INTEGRATION);
1802 /* If inlining succeeded, return. */
1803 if (temp != (rtx) (HOST_WIDE_INT) - 1)
1805 if (ACCUMULATE_OUTGOING_ARGS)
1807 /* If the outgoing argument list must be preserved, push
1808 the stack before executing the inlined function if it
1811 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1812 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1815 if (stack_arg_under_construction || i >= 0)
1818 = before_call ? NEXT_INSN (before_call) : get_insns ();
1819 rtx insn = NULL_RTX, seq;
1821 /* Look for a call in the inline function code.
1822 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1823 nonzero then there is a call and it is not necessary
1824 to scan the insns. */
1826 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1827 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1828 if (GET_CODE (insn) == CALL_INSN)
1833 /* Reserve enough stack space so that the largest
1834 argument list of any function call in the inline
1835 function does not overlap the argument list being
1836 evaluated. This is usually an overestimate because
1837 allocate_dynamic_stack_space reserves space for an
1838 outgoing argument list in addition to the requested
1839 space, but there is no way to ask for stack space such
1840 that an argument list of a certain length can be
1843 Add the stack space reserved for register arguments, if
1844 any, in the inline function. What is really needed is the
1845 largest value of reg_parm_stack_space in the inline
1846 function, but that is not available. Using the current
1847 value of reg_parm_stack_space is wrong, but gives
1848 correct results on all supported machines. */
1850 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1851 + reg_parm_stack_space);
1854 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1855 allocate_dynamic_stack_space (GEN_INT (adjust),
1856 NULL_RTX, BITS_PER_UNIT);
1859 emit_insns_before (seq, first_insn);
1860 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1865 /* If the result is equivalent to TARGET, return TARGET to simplify
1866 checks in store_expr. They can be equivalent but not equal in the
1867 case of a function that returns BLKmode. */
1868 if (temp != target && rtx_equal_p (temp, target))
1873 /* If inlining failed, mark FNDECL as needing to be compiled
1874 separately after all. If function was declared inline,
1876 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1877 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1879 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1880 warning ("called from here");
1882 mark_addressable (fndecl);
1883 return (rtx) (HOST_WIDE_INT) - 1;
1886 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1887 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1888 bytes, then we would need to push some additional bytes to pad the
1889 arguments. So, we compute an adjust to the stack pointer for an
1890 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1891 bytes. Then, when the arguments are pushed the stack will be perfectly
1892 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1893 be popped after the call. Returns the adjustment. */
1896 combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1898 preferred_unit_stack_boundary)
1899 int unadjusted_args_size;
1900 struct args_size *args_size;
1901 int preferred_unit_stack_boundary;
1903 /* The number of bytes to pop so that the stack will be
1904 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1905 HOST_WIDE_INT adjustment;
1906 /* The alignment of the stack after the arguments are pushed, if we
1907 just pushed the arguments without adjust the stack here. */
1908 HOST_WIDE_INT unadjusted_alignment;
1910 unadjusted_alignment
1911 = ((stack_pointer_delta + unadjusted_args_size)
1912 % preferred_unit_stack_boundary);
1914 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1915 as possible -- leaving just enough left to cancel out the
1916 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1917 PENDING_STACK_ADJUST is non-negative, and congruent to
1918 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1920 /* Begin by trying to pop all the bytes. */
1921 unadjusted_alignment
1922 = (unadjusted_alignment
1923 - (pending_stack_adjust % preferred_unit_stack_boundary));
1924 adjustment = pending_stack_adjust;
1925 /* Push enough additional bytes that the stack will be aligned
1926 after the arguments are pushed. */
1927 if (preferred_unit_stack_boundary > 1)
1929 if (unadjusted_alignment >= 0)
1930 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1932 adjustment += unadjusted_alignment;
1935 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1936 bytes after the call. The right number is the entire
1937 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1938 by the arguments in the first place. */
1940 = pending_stack_adjust - adjustment + unadjusted_args_size;
1945 /* Scan X expression if it does not dereference any argument slots
1946 we already clobbered by tail call arguments (as noted in stored_args_map
1948 Return non-zero if X expression dereferences such argument slots,
1952 check_sibcall_argument_overlap_1 (x)
1963 code = GET_CODE (x);
1967 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1969 else if (GET_CODE (XEXP (x, 0)) == PLUS
1970 && XEXP (XEXP (x, 0), 0) ==
1971 current_function_internal_arg_pointer
1972 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1973 i = INTVAL (XEXP (XEXP (x, 0), 1));
1977 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
1978 if (i + k < stored_args_map->n_bits
1979 && TEST_BIT (stored_args_map, i + k))
1985 /* Scan all subexpressions. */
1986 fmt = GET_RTX_FORMAT (code);
1987 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1991 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
1994 else if (*fmt == 'E')
1996 for (j = 0; j < XVECLEN (x, i); j++)
1997 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2005 /* Scan sequence after INSN if it does not dereference any argument slots
2006 we already clobbered by tail call arguments (as noted in stored_args_map
2007 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2008 Return non-zero if sequence after INSN dereferences such argument slots,
2012 check_sibcall_argument_overlap (insn, arg)
2014 struct arg_data *arg;
2018 if (insn == NULL_RTX)
2019 insn = get_insns ();
2021 insn = NEXT_INSN (insn);
2023 for (; insn; insn = NEXT_INSN (insn))
2024 if (INSN_P (insn) &&
2025 check_sibcall_argument_overlap_1 (PATTERN (insn)))
2028 low = arg->offset.constant;
2029 for (high = low + arg->size.constant; low < high; low++)
2030 SET_BIT (stored_args_map, low);
2031 return insn != NULL_RTX;
2034 /* Generate all the code for a function call
2035 and return an rtx for its value.
2036 Store the value in TARGET (specified as an rtx) if convenient.
2037 If the value is stored in TARGET then TARGET is returned.
2038 If IGNORE is nonzero, then we ignore the value of the function call. */
2041 expand_call (exp, target, ignore)
2046 /* Nonzero if we are currently expanding a call. */
2047 static int currently_expanding_call = 0;
2049 /* List of actual parameters. */
2050 tree actparms = TREE_OPERAND (exp, 1);
2051 /* RTX for the function to be called. */
2053 /* Sequence of insns to perform a tail recursive "call". */
2054 rtx tail_recursion_insns = NULL_RTX;
2055 /* Sequence of insns to perform a normal "call". */
2056 rtx normal_call_insns = NULL_RTX;
2057 /* Sequence of insns to perform a tail recursive "call". */
2058 rtx tail_call_insns = NULL_RTX;
2059 /* Data type of the function. */
2061 /* Declaration of the function being called,
2062 or 0 if the function is computed (not known by name). */
2066 int try_tail_call = 1;
2067 int try_tail_recursion = 1;
2070 /* Register in which non-BLKmode value will be returned,
2071 or 0 if no value or if value is BLKmode. */
2073 /* Address where we should return a BLKmode value;
2074 0 if value not BLKmode. */
2075 rtx structure_value_addr = 0;
2076 /* Nonzero if that address is being passed by treating it as
2077 an extra, implicit first parameter. Otherwise,
2078 it is passed by being copied directly into struct_value_rtx. */
2079 int structure_value_addr_parm = 0;
2080 /* Size of aggregate value wanted, or zero if none wanted
2081 or if we are using the non-reentrant PCC calling convention
2082 or expecting the value in registers. */
2083 HOST_WIDE_INT struct_value_size = 0;
2084 /* Nonzero if called function returns an aggregate in memory PCC style,
2085 by returning the address of where to find it. */
2086 int pcc_struct_value = 0;
2088 /* Number of actual parameters in this call, including struct value addr. */
2090 /* Number of named args. Args after this are anonymous ones
2091 and they must all go on the stack. */
2094 /* Vector of information about each argument.
2095 Arguments are numbered in the order they will be pushed,
2096 not the order they are written. */
2097 struct arg_data *args;
2099 /* Total size in bytes of all the stack-parms scanned so far. */
2100 struct args_size args_size;
2101 struct args_size adjusted_args_size;
2102 /* Size of arguments before any adjustments (such as rounding). */
2103 int unadjusted_args_size;
2104 /* Data on reg parms scanned so far. */
2105 CUMULATIVE_ARGS args_so_far;
2106 /* Nonzero if a reg parm has been scanned. */
2108 /* Nonzero if this is an indirect function call. */
2110 /* Nonzero if we must avoid push-insns in the args for this call.
2111 If stack space is allocated for register parameters, but not by the
2112 caller, then it is preallocated in the fixed part of the stack frame.
2113 So the entire argument block must then be preallocated (i.e., we
2114 ignore PUSH_ROUNDING in that case). */
2116 int must_preallocate = !PUSH_ARGS;
2118 /* Size of the stack reserved for parameter registers. */
2119 int reg_parm_stack_space = 0;
2121 /* Address of space preallocated for stack parms
2122 (on machines that lack push insns), or 0 if space not preallocated. */
2125 /* Mask of ECF_ flags. */
2127 /* Nonzero if this is a call to an inline function. */
2128 int is_integrable = 0;
2129 #ifdef REG_PARM_STACK_SPACE
2130 /* Define the boundary of the register parm stack space that needs to be
2132 int low_to_save = -1, high_to_save;
2133 rtx save_area = 0; /* Place that it is saved */
2136 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2137 char *initial_stack_usage_map = stack_usage_map;
2138 int old_stack_arg_under_construction = 0;
2140 rtx old_stack_level = 0;
2141 int old_pending_adj = 0;
2142 int old_inhibit_defer_pop = inhibit_defer_pop;
2143 int old_stack_allocated;
2145 register tree p = TREE_OPERAND (exp, 0);
2147 /* The alignment of the stack, in bits. */
2148 HOST_WIDE_INT preferred_stack_boundary;
2149 /* The alignment of the stack, in bytes. */
2150 HOST_WIDE_INT preferred_unit_stack_boundary;
2152 /* The value of the function call can be put in a hard register. But
2153 if -fcheck-memory-usage, code which invokes functions (and thus
2154 damages some hard registers) can be inserted before using the value.
2155 So, target is always a pseudo-register in that case. */
2156 if (current_function_check_memory_usage)
2159 /* See if this is "nothrow" function call. */
2160 if (TREE_NOTHROW (exp))
2161 flags |= ECF_NOTHROW;
2163 /* See if we can find a DECL-node for the actual function.
2164 As a result, decide whether this is a call to an integrable function. */
2166 fndecl = get_callee_fndecl (exp);
2170 && fndecl != current_function_decl
2171 && DECL_INLINE (fndecl)
2172 && DECL_SAVED_INSNS (fndecl)
2173 && DECL_SAVED_INSNS (fndecl)->inlinable)
2175 else if (! TREE_ADDRESSABLE (fndecl))
2177 /* In case this function later becomes inlinable,
2178 record that there was already a non-inline call to it.
2180 Use abstraction instead of setting TREE_ADDRESSABLE
2182 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2185 warning_with_decl (fndecl, "can't inline call to `%s'");
2186 warning ("called from here");
2188 mark_addressable (fndecl);
2191 flags |= flags_from_decl_or_type (fndecl);
2194 /* If we don't have specific function to call, see if we have a
2195 attributes set in the type. */
2197 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2199 /* Mark if the function returns with the stack pointer depressed. */
2200 if (TREE_CODE (TREE_TYPE (TREE_TYPE (p))) == FUNCTION_TYPE
2201 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (TREE_TYPE (p))))
2203 flags |= ECF_SP_DEPRESSED;
2204 flags &= ~ (ECF_PURE | ECF_CONST);
2207 #ifdef REG_PARM_STACK_SPACE
2208 #ifdef MAYBE_REG_PARM_STACK_SPACE
2209 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2211 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2215 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2216 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2217 must_preallocate = 1;
2220 /* Warn if this value is an aggregate type,
2221 regardless of which calling convention we are using for it. */
2222 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2223 warning ("function call has aggregate value");
2225 /* Set up a place to return a structure. */
2227 /* Cater to broken compilers. */
2228 if (aggregate_value_p (exp))
2230 /* This call returns a big structure. */
2231 flags &= ~(ECF_CONST | ECF_PURE);
2233 #ifdef PCC_STATIC_STRUCT_RETURN
2235 pcc_struct_value = 1;
2236 /* Easier than making that case work right. */
2239 /* In case this is a static function, note that it has been
2241 if (! TREE_ADDRESSABLE (fndecl))
2242 mark_addressable (fndecl);
2246 #else /* not PCC_STATIC_STRUCT_RETURN */
2248 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2250 if (target && GET_CODE (target) == MEM)
2251 structure_value_addr = XEXP (target, 0);
2254 /* Assign a temporary to hold the value. */
2257 /* For variable-sized objects, we must be called with a target
2258 specified. If we were to allocate space on the stack here,
2259 we would have no way of knowing when to free it. */
2261 if (struct_value_size < 0)
2264 /* This DECL is just something to feed to mark_addressable;
2265 it doesn't get pushed. */
2266 d = build_decl (VAR_DECL, NULL_TREE, TREE_TYPE (exp));
2267 DECL_RTL (d) = assign_temp (TREE_TYPE (exp), 1, 0, 1);
2268 mark_addressable (d);
2269 mark_temp_addr_taken (DECL_RTL (d));
2270 structure_value_addr = XEXP (DECL_RTL (d), 0);
2275 #endif /* not PCC_STATIC_STRUCT_RETURN */
2278 /* If called function is inline, try to integrate it. */
2282 rtx temp = try_to_integrate (fndecl, actparms, target,
2283 ignore, TREE_TYPE (exp),
2284 structure_value_addr);
2285 if (temp != (rtx) (HOST_WIDE_INT) - 1)
2289 if (fndecl && DECL_NAME (fndecl))
2290 name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
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));
2378 /* Make a vector to hold all the information about each arg. */
2379 args = (struct arg_data *) alloca (num_actuals
2380 * sizeof (struct arg_data));
2381 bzero ((char *) args, num_actuals * sizeof (struct arg_data));
2383 /* Build up entries inthe ARGS array, compute the size of the arguments
2384 into ARGS_SIZE, etc. */
2385 initialize_argument_information (num_actuals, args, &args_size,
2386 n_named_args, actparms, fndecl,
2387 &args_so_far, reg_parm_stack_space,
2388 &old_stack_level, &old_pending_adj,
2389 &must_preallocate, &flags);
2393 /* If this function requires a variable-sized argument list, don't
2394 try to make a cse'able block for this call. We may be able to
2395 do this eventually, but it is too complicated to keep track of
2396 what insns go in the cse'able block and which don't. */
2398 flags &= ~(ECF_CONST | ECF_PURE);
2399 must_preallocate = 1;
2402 /* Now make final decision about preallocating stack space. */
2403 must_preallocate = finalize_must_preallocate (must_preallocate,
2407 /* If the structure value address will reference the stack pointer, we
2408 must stabilize it. We don't need to do this if we know that we are
2409 not going to adjust the stack pointer in processing this call. */
2411 if (structure_value_addr
2412 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2413 || reg_mentioned_p (virtual_outgoing_args_rtx,
2414 structure_value_addr))
2416 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2417 structure_value_addr = copy_to_reg (structure_value_addr);
2419 /* Tail calls can make things harder to debug, and we're traditionally
2420 pushed these optimizations into -O2. Don't try if we're already
2421 expanding a call, as that means we're an argument. Similarly, if
2422 there's pending loops or cleanups we know there's code to follow
2425 If rtx_equal_function_value_matters is false, that means we've
2426 finished with regular parsing. Which means that some of the
2427 machinery we use to generate tail-calls is no longer in place.
2428 This is most often true of sjlj-exceptions, which we couldn't
2429 tail-call to anyway. */
2431 if (currently_expanding_call++ != 0
2432 || !flag_optimize_sibling_calls
2433 || !rtx_equal_function_value_matters
2434 || !stmt_loop_nest_empty ()
2435 || any_pending_cleanups (1)
2437 try_tail_call = try_tail_recursion = 0;
2439 /* Tail recursion fails, when we are not dealing with recursive calls. */
2440 if (!try_tail_recursion
2441 || TREE_CODE (TREE_OPERAND (exp, 0)) != ADDR_EXPR
2442 || TREE_OPERAND (TREE_OPERAND (exp, 0), 0) != current_function_decl)
2443 try_tail_recursion = 0;
2445 /* Rest of purposes for tail call optimizations to fail. */
2447 #ifdef HAVE_sibcall_epilogue
2448 !HAVE_sibcall_epilogue
2453 /* Doing sibling call optimization needs some work, since
2454 structure_value_addr can be allocated on the stack.
2455 It does not seem worth the effort since few optimizable
2456 sibling calls will return a structure. */
2457 || structure_value_addr != NULL_RTX
2458 /* If the register holding the address is a callee saved
2459 register, then we lose. We have no way to prevent that,
2460 so we only allow calls to named functions. */
2461 /* ??? This could be done by having the insn constraints
2462 use a register class that is all call-clobbered. Any
2463 reload insns generated to fix things up would appear
2464 before the sibcall_epilogue. */
2465 || fndecl == NULL_TREE
2466 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP))
2467 || !FUNCTION_OK_FOR_SIBCALL (fndecl)
2468 /* If this function requires more stack slots than the current
2469 function, we cannot change it into a sibling call. */
2470 || args_size.constant > current_function_args_size
2471 /* If the callee pops its own arguments, then it must pop exactly
2472 the same number of arguments as the current function. */
2473 || RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2474 != RETURN_POPS_ARGS (current_function_decl,
2475 TREE_TYPE (current_function_decl),
2476 current_function_args_size))
2479 if (try_tail_call || try_tail_recursion)
2482 actparms = NULL_TREE;
2483 /* Ok, we're going to give the tail call the old college try.
2484 This means we're going to evaluate the function arguments
2485 up to three times. There are two degrees of badness we can
2486 encounter, those that can be unsaved and those that can't.
2487 (See unsafe_for_reeval commentary for details.)
2489 Generate a new argument list. Pass safe arguments through
2490 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2491 For hard badness, evaluate them now and put their resulting
2492 rtx in a temporary VAR_DECL.
2494 initialize_argument_information has ordered the array for the
2495 order to be pushed, and we must remember this when reconstructing
2496 the original argument orde. */
2498 if (PUSH_ARGS_REVERSED)
2507 i = num_actuals - 1;
2511 for (; i != end; i += inc)
2513 switch (unsafe_for_reeval (args[i].tree_value))
2518 case 1: /* Mildly unsafe. */
2519 args[i].tree_value = unsave_expr (args[i].tree_value);
2522 case 2: /* Wildly unsafe. */
2524 tree var = build_decl (VAR_DECL, NULL_TREE,
2525 TREE_TYPE (args[i].tree_value));
2526 DECL_RTL (var) = expand_expr (args[i].tree_value, NULL_RTX,
2527 VOIDmode, EXPAND_NORMAL);
2528 args[i].tree_value = var;
2535 /* We need to build actparms for optimize_tail_recursion. We can
2536 safely trash away TREE_PURPOSE, since it is unused by this
2538 if (try_tail_recursion)
2539 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2541 /* Expanding one of those dangerous arguments could have added
2542 cleanups, but otherwise give it a whirl. */
2543 if (any_pending_cleanups (1))
2544 try_tail_call = try_tail_recursion = 0;
2547 /* Generate a tail recursion sequence when calling ourselves. */
2549 if (try_tail_recursion)
2551 /* We want to emit any pending stack adjustments before the tail
2552 recursion "call". That way we know any adjustment after the tail
2553 recursion call can be ignored if we indeed use the tail recursion
2555 int save_pending_stack_adjust = pending_stack_adjust;
2556 int save_stack_pointer_delta = stack_pointer_delta;
2558 /* Use a new sequence to hold any RTL we generate. We do not even
2559 know if we will use this RTL yet. The final decision can not be
2560 made until after RTL generation for the entire function is
2563 /* If expanding any of the arguments creates cleanups, we can't
2564 do a tailcall. So, we'll need to pop the pending cleanups
2565 list. If, however, all goes well, and there are no cleanups
2566 then the call to expand_start_target_temps will have no
2568 expand_start_target_temps ();
2569 if (optimize_tail_recursion (actparms, get_last_insn ()))
2571 if (any_pending_cleanups (1))
2572 try_tail_call = try_tail_recursion = 0;
2574 tail_recursion_insns = get_insns ();
2576 expand_end_target_temps ();
2579 /* Restore the original pending stack adjustment for the sibling and
2580 normal call cases below. */
2581 pending_stack_adjust = save_pending_stack_adjust;
2582 stack_pointer_delta = save_stack_pointer_delta;
2585 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2587 /* A fork duplicates the profile information, and an exec discards
2588 it. We can't rely on fork/exec to be paired. So write out the
2589 profile information we have gathered so far, and clear it. */
2590 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2591 is subject to race conditions, just as with multithreaded
2594 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__bb_fork_func"), 0,
2598 /* Ensure current function's preferred stack boundary is at least
2599 what we need. We don't have to increase alignment for recursive
2601 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2602 && fndecl != current_function_decl)
2603 cfun->preferred_stack_boundary = preferred_stack_boundary;
2605 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2607 function_call_count++;
2609 /* We want to make two insn chains; one for a sibling call, the other
2610 for a normal call. We will select one of the two chains after
2611 initial RTL generation is complete. */
2612 for (pass = 0; pass < 2; pass++)
2614 int sibcall_failure = 0;
2615 /* We want to emit ay pending stack adjustments before the tail
2616 recursion "call". That way we know any adjustment after the tail
2617 recursion call can be ignored if we indeed use the tail recursion
2619 int save_pending_stack_adjust = 0;
2620 int save_stack_pointer_delta = 0;
2622 rtx before_call, next_arg_reg;
2626 if (! try_tail_call)
2629 /* Emit any queued insns now; otherwise they would end up in
2630 only one of the alternates. */
2633 /* State variables we need to save and restore between
2635 save_pending_stack_adjust = pending_stack_adjust;
2636 save_stack_pointer_delta = stack_pointer_delta;
2639 flags &= ~ECF_SIBCALL;
2641 flags |= ECF_SIBCALL;
2643 /* Other state variables that we must reinitialize each time
2644 through the loop (that are not initialized by the loop itself). */
2648 /* Start a new sequence for the normal call case.
2650 From this point on, if the sibling call fails, we want to set
2651 sibcall_failure instead of continuing the loop. */
2656 /* We know at this point that there are not currently any
2657 pending cleanups. If, however, in the process of evaluating
2658 the arguments we were to create some, we'll need to be
2659 able to get rid of them. */
2660 expand_start_target_temps ();
2663 /* When calling a const function, we must pop the stack args right away,
2664 so that the pop is deleted or moved with the call. */
2665 if (flags & (ECF_CONST | ECF_PURE))
2668 /* Don't let pending stack adjusts add up to too much.
2669 Also, do all pending adjustments now if there is any chance
2670 this might be a call to alloca or if we are expanding a sibling
2672 if (pending_stack_adjust >= 32
2673 || (pending_stack_adjust > 0 && (flags & ECF_MAY_BE_ALLOCA))
2675 do_pending_stack_adjust ();
2677 /* Push the temporary stack slot level so that we can free any
2678 temporaries we make. */
2682 #ifdef FINAL_REG_PARM_STACK_SPACE
2683 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2686 /* Precompute any arguments as needed. */
2688 precompute_arguments (flags, num_actuals, args);
2690 /* Now we are about to start emitting insns that can be deleted
2691 if a libcall is deleted. */
2692 if (flags & (ECF_CONST | ECF_PURE | ECF_MALLOC))
2695 adjusted_args_size = args_size;
2696 /* Compute the actual size of the argument block required. The variable
2697 and constant sizes must be combined, the size may have to be rounded,
2698 and there may be a minimum required size. When generating a sibcall
2699 pattern, do not round up, since we'll be re-using whatever space our
2701 unadjusted_args_size
2702 = compute_argument_block_size (reg_parm_stack_space, &adjusted_args_size,
2704 : preferred_stack_boundary));
2706 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2708 /* The argument block when performing a sibling call is the
2709 incoming argument block. */
2712 argblock = virtual_incoming_args_rtx;
2713 stored_args_map = sbitmap_alloc (args_size.constant);
2714 sbitmap_zero (stored_args_map);
2717 /* If we have no actual push instructions, or shouldn't use them,
2718 make space for all args right now. */
2719 else if (adjusted_args_size.var != 0)
2721 if (old_stack_level == 0)
2723 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2724 old_pending_adj = pending_stack_adjust;
2725 pending_stack_adjust = 0;
2726 /* stack_arg_under_construction says whether a stack arg is
2727 being constructed at the old stack level. Pushing the stack
2728 gets a clean outgoing argument block. */
2729 old_stack_arg_under_construction = stack_arg_under_construction;
2730 stack_arg_under_construction = 0;
2732 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2736 /* Note that we must go through the motions of allocating an argument
2737 block even if the size is zero because we may be storing args
2738 in the area reserved for register arguments, which may be part of
2741 int needed = adjusted_args_size.constant;
2743 /* Store the maximum argument space used. It will be pushed by
2744 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2747 if (needed > current_function_outgoing_args_size)
2748 current_function_outgoing_args_size = needed;
2750 if (must_preallocate)
2752 if (ACCUMULATE_OUTGOING_ARGS)
2754 /* Since the stack pointer will never be pushed, it is
2755 possible for the evaluation of a parm to clobber
2756 something we have already written to the stack.
2757 Since most function calls on RISC machines do not use
2758 the stack, this is uncommon, but must work correctly.
2760 Therefore, we save any area of the stack that was already
2761 written and that we are using. Here we set up to do this
2762 by making a new stack usage map from the old one. The
2763 actual save will be done by store_one_arg.
2765 Another approach might be to try to reorder the argument
2766 evaluations to avoid this conflicting stack usage. */
2768 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2769 /* Since we will be writing into the entire argument area,
2770 the map must be allocated for its entire size, not just
2771 the part that is the responsibility of the caller. */
2772 needed += reg_parm_stack_space;
2775 #ifdef ARGS_GROW_DOWNWARD
2776 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2779 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2783 = (char *) alloca (highest_outgoing_arg_in_use);
2785 if (initial_highest_arg_in_use)
2786 bcopy (initial_stack_usage_map, stack_usage_map,
2787 initial_highest_arg_in_use);
2789 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2790 bzero (&stack_usage_map[initial_highest_arg_in_use],
2791 (highest_outgoing_arg_in_use
2792 - initial_highest_arg_in_use));
2795 /* The address of the outgoing argument list must not be
2796 copied to a register here, because argblock would be left
2797 pointing to the wrong place after the call to
2798 allocate_dynamic_stack_space below. */
2800 argblock = virtual_outgoing_args_rtx;
2804 if (inhibit_defer_pop == 0)
2806 /* Try to reuse some or all of the pending_stack_adjust
2807 to get this space. */
2809 = (combine_pending_stack_adjustment_and_call
2810 (unadjusted_args_size,
2811 &adjusted_args_size,
2812 preferred_unit_stack_boundary));
2814 /* combine_pending_stack_adjustment_and_call computes
2815 an adjustment before the arguments are allocated.
2816 Account for them and see whether or not the stack
2817 needs to go up or down. */
2818 needed = unadjusted_args_size - needed;
2822 /* We're releasing stack space. */
2823 /* ??? We can avoid any adjustment at all if we're
2824 already aligned. FIXME. */
2825 pending_stack_adjust = -needed;
2826 do_pending_stack_adjust ();
2830 /* We need to allocate space. We'll do that in
2831 push_block below. */
2832 pending_stack_adjust = 0;
2835 /* Special case this because overhead of `push_block' in
2836 this case is non-trivial. */
2838 argblock = virtual_outgoing_args_rtx;
2840 argblock = push_block (GEN_INT (needed), 0, 0);
2842 /* We only really need to call `copy_to_reg' in the case
2843 where push insns are going to be used to pass ARGBLOCK
2844 to a function call in ARGS. In that case, the stack
2845 pointer changes value from the allocation point to the
2846 call point, and hence the value of
2847 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2848 as well always do it. */
2849 argblock = copy_to_reg (argblock);
2851 /* The save/restore code in store_one_arg handles all
2852 cases except one: a constructor call (including a C
2853 function returning a BLKmode struct) to initialize
2855 if (stack_arg_under_construction)
2857 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2858 rtx push_size = GEN_INT (reg_parm_stack_space
2859 + adjusted_args_size.constant);
2861 rtx push_size = GEN_INT (adjusted_args_size.constant);
2863 if (old_stack_level == 0)
2865 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2867 old_pending_adj = pending_stack_adjust;
2868 pending_stack_adjust = 0;
2869 /* stack_arg_under_construction says whether a stack
2870 arg is being constructed at the old stack level.
2871 Pushing the stack gets a clean outgoing argument
2873 old_stack_arg_under_construction
2874 = stack_arg_under_construction;
2875 stack_arg_under_construction = 0;
2876 /* Make a new map for the new argument list. */
2877 stack_usage_map = (char *)
2878 alloca (highest_outgoing_arg_in_use);
2879 bzero (stack_usage_map, highest_outgoing_arg_in_use);
2880 highest_outgoing_arg_in_use = 0;
2882 allocate_dynamic_stack_space (push_size, NULL_RTX,
2885 /* If argument evaluation might modify the stack pointer,
2886 copy the address of the argument list to a register. */
2887 for (i = 0; i < num_actuals; i++)
2888 if (args[i].pass_on_stack)
2890 argblock = copy_addr_to_reg (argblock);
2897 compute_argument_addresses (args, argblock, num_actuals);
2899 #ifdef PREFERRED_STACK_BOUNDARY
2900 /* If we push args individually in reverse order, perform stack alignment
2901 before the first push (the last arg). */
2902 if (PUSH_ARGS_REVERSED && argblock == 0
2903 && adjusted_args_size.constant != unadjusted_args_size)
2905 /* When the stack adjustment is pending, we get better code
2906 by combining the adjustments. */
2907 if (pending_stack_adjust
2908 && ! (flags & (ECF_CONST | ECF_PURE))
2909 && ! inhibit_defer_pop)
2911 pending_stack_adjust
2912 = (combine_pending_stack_adjustment_and_call
2913 (unadjusted_args_size,
2914 &adjusted_args_size,
2915 preferred_unit_stack_boundary));
2916 do_pending_stack_adjust ();
2918 else if (argblock == 0)
2919 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2920 - unadjusted_args_size));
2922 /* Now that the stack is properly aligned, pops can't safely
2923 be deferred during the evaluation of the arguments. */
2927 /* Don't try to defer pops if preallocating, not even from the first arg,
2928 since ARGBLOCK probably refers to the SP. */
2932 funexp = rtx_for_function_call (fndecl, exp);
2934 /* Figure out the register where the value, if any, will come back. */
2936 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2937 && ! structure_value_addr)
2939 if (pcc_struct_value)
2940 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2941 fndecl, (pass == 0));
2943 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2946 /* Precompute all register parameters. It isn't safe to compute anything
2947 once we have started filling any specific hard regs. */
2948 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2950 #ifdef REG_PARM_STACK_SPACE
2951 /* Save the fixed argument area if it's part of the caller's frame and
2952 is clobbered by argument setup for this call. */
2953 if (ACCUMULATE_OUTGOING_ARGS && pass)
2954 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2955 &low_to_save, &high_to_save);
2958 /* Now store (and compute if necessary) all non-register parms.
2959 These come before register parms, since they can require block-moves,
2960 which could clobber the registers used for register parms.
2961 Parms which have partial registers are not stored here,
2962 but we do preallocate space here if they want that. */
2964 for (i = 0; i < num_actuals; i++)
2965 if (args[i].reg == 0 || args[i].pass_on_stack)
2967 rtx before_arg = get_last_insn ();
2969 if (store_one_arg (&args[i], argblock, flags,
2970 adjusted_args_size.var != 0,
2971 reg_parm_stack_space)
2973 && check_sibcall_argument_overlap (before_arg,
2975 sibcall_failure = 1;
2978 /* If we have a parm that is passed in registers but not in memory
2979 and whose alignment does not permit a direct copy into registers,
2980 make a group of pseudos that correspond to each register that we
2982 if (STRICT_ALIGNMENT)
2983 store_unaligned_arguments_into_pseudos (args, num_actuals);
2985 /* Now store any partially-in-registers parm.
2986 This is the last place a block-move can happen. */
2988 for (i = 0; i < num_actuals; i++)
2989 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2991 rtx before_arg = get_last_insn ();
2993 if (store_one_arg (&args[i], argblock, flags,
2994 adjusted_args_size.var != 0,
2995 reg_parm_stack_space)
2997 && check_sibcall_argument_overlap (before_arg,
2999 sibcall_failure = 1;
3002 #ifdef PREFERRED_STACK_BOUNDARY
3003 /* If we pushed args in forward order, perform stack alignment
3004 after pushing the last arg. */
3005 if (!PUSH_ARGS_REVERSED && argblock == 0)
3006 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3007 - unadjusted_args_size));
3010 /* If register arguments require space on the stack and stack space
3011 was not preallocated, allocate stack space here for arguments
3012 passed in registers. */
3013 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3014 if (!ACCUMULATE_OUTGOING_ARGS
3015 && must_preallocate == 0 && reg_parm_stack_space > 0)
3016 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3019 /* Pass the function the address in which to return a
3021 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3023 emit_move_insn (struct_value_rtx,
3025 force_operand (structure_value_addr,
3028 /* Mark the memory for the aggregate as write-only. */
3029 if (current_function_check_memory_usage)
3030 emit_library_call (chkr_set_right_libfunc, 1,
3032 structure_value_addr, ptr_mode,
3033 GEN_INT (struct_value_size),
3034 TYPE_MODE (sizetype),
3035 GEN_INT (MEMORY_USE_WO),
3036 TYPE_MODE (integer_type_node));
3038 if (GET_CODE (struct_value_rtx) == REG)
3039 use_reg (&call_fusage, struct_value_rtx);
3042 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3045 load_register_parameters (args, num_actuals, &call_fusage, flags);
3047 /* Perform postincrements before actually calling the function. */
3050 /* Save a pointer to the last insn before the call, so that we can
3051 later safely search backwards to find the CALL_INSN. */
3052 before_call = get_last_insn ();
3054 /* Set up next argument register. For sibling calls on machines
3055 with register windows this should be the incoming register. */
3056 #ifdef FUNCTION_INCOMING_ARG
3058 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3062 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3065 /* All arguments and registers used for the call must be set up by
3068 #ifdef PREFERRED_STACK_BOUNDARY
3069 /* Stack must be properly aligned now. */
3070 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3074 /* Generate the actual call instruction. */
3075 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3076 adjusted_args_size.constant, struct_value_size,
3077 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3080 /* Verify that we've deallocated all the stack we used. */
3082 && old_stack_allocated != stack_pointer_delta - pending_stack_adjust)
3085 /* If call is cse'able, make appropriate pair of reg-notes around it.
3086 Test valreg so we don't crash; may safely ignore `const'
3087 if return type is void. Disable for PARALLEL return values, because
3088 we have no way to move such values into a pseudo register. */
3090 && (flags & (ECF_CONST | ECF_PURE))
3091 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
3094 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3097 /* Mark the return value as a pointer if needed. */
3098 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3099 mark_reg_pointer (temp, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3101 /* Construct an "equal form" for the value which mentions all the
3102 arguments in order as well as the function name. */
3103 for (i = 0; i < num_actuals; i++)
3104 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
3105 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3107 insns = get_insns ();
3110 if (flags & ECF_PURE)
3111 note = gen_rtx_EXPR_LIST (VOIDmode,
3112 gen_rtx_USE (VOIDmode,
3113 gen_rtx_MEM (BLKmode,
3114 gen_rtx_SCRATCH (VOIDmode))), note);
3116 emit_libcall_block (insns, temp, valreg, note);
3120 else if (flags & (ECF_CONST | ECF_PURE))
3122 /* Otherwise, just write out the sequence without a note. */
3123 rtx insns = get_insns ();
3128 else if (flags & ECF_MALLOC)
3130 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3133 /* The return value from a malloc-like function is a pointer. */
3134 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3135 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3137 emit_move_insn (temp, valreg);
3139 /* The return value from a malloc-like function can not alias
3141 last = get_last_insn ();
3143 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3145 /* Write out the sequence. */
3146 insns = get_insns ();
3152 /* For calls to `setjmp', etc., inform flow.c it should complain
3153 if nonvolatile values are live. For functions that cannot return,
3154 inform flow that control does not fall through. */
3156 if ((flags & (ECF_RETURNS_TWICE | ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3158 /* The barrier or NOTE_INSN_SETJMP note must be emitted
3159 immediately after the CALL_INSN. Some ports emit more
3160 than just a CALL_INSN above, so we must search for it here. */
3162 rtx last = get_last_insn ();
3163 while (GET_CODE (last) != CALL_INSN)
3165 last = PREV_INSN (last);
3166 /* There was no CALL_INSN? */
3167 if (last == before_call)
3171 if (flags & ECF_RETURNS_TWICE)
3173 emit_note_after (NOTE_INSN_SETJMP, last);
3174 current_function_calls_setjmp = 1;
3177 emit_barrier_after (last);
3180 if (flags & ECF_LONGJMP)
3181 current_function_calls_longjmp = 1;
3183 /* If this function is returning into a memory location marked as
3184 readonly, it means it is initializing that location. But we normally
3185 treat functions as not clobbering such locations, so we need to
3186 specify that this one does. */
3187 if (target != 0 && GET_CODE (target) == MEM
3188 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
3189 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
3191 /* If value type not void, return an rtx for the value. */
3193 /* If there are cleanups to be called, don't use a hard reg as target.
3194 We need to double check this and see if it matters anymore. */
3195 if (any_pending_cleanups (1))
3197 if (target && REG_P (target)
3198 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3200 sibcall_failure = 1;
3203 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3206 target = const0_rtx;
3208 else if (structure_value_addr)
3210 if (target == 0 || GET_CODE (target) != MEM)
3213 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3214 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3215 structure_value_addr));
3216 set_mem_attributes (target, exp, 1);
3219 else if (pcc_struct_value)
3221 /* This is the special C++ case where we need to
3222 know what the true target was. We take care to
3223 never use this value more than once in one expression. */
3224 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3225 copy_to_reg (valreg));
3226 set_mem_attributes (target, exp, 1);
3228 /* Handle calls that return values in multiple non-contiguous locations.
3229 The Irix 6 ABI has examples of this. */
3230 else if (GET_CODE (valreg) == PARALLEL)
3232 int bytes = int_size_in_bytes (TREE_TYPE (exp));
3236 target = assign_stack_temp (TYPE_MODE (TREE_TYPE (exp)),
3238 MEM_SET_IN_STRUCT_P (target, AGGREGATE_TYPE_P (TREE_TYPE (exp)));
3239 preserve_temp_slots (target);
3242 if (! rtx_equal_p (target, valreg))
3243 emit_group_store (target, valreg, bytes,
3244 TYPE_ALIGN (TREE_TYPE (exp)));
3246 /* We can not support sibling calls for this case. */
3247 sibcall_failure = 1;
3250 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3251 && GET_MODE (target) == GET_MODE (valreg))
3253 /* TARGET and VALREG cannot be equal at this point because the
3254 latter would not have REG_FUNCTION_VALUE_P true, while the
3255 former would if it were referring to the same register.
3257 If they refer to the same register, this move will be a no-op,
3258 except when function inlining is being done. */
3259 emit_move_insn (target, valreg);
3261 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3262 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3264 target = copy_to_reg (valreg);
3266 #ifdef PROMOTE_FUNCTION_RETURN
3267 /* If we promoted this return value, make the proper SUBREG. TARGET
3268 might be const0_rtx here, so be careful. */
3269 if (GET_CODE (target) == REG
3270 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3271 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3273 tree type = TREE_TYPE (exp);
3274 int unsignedp = TREE_UNSIGNED (type);
3276 /* If we don't promote as expected, something is wrong. */
3277 if (GET_MODE (target)
3278 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3281 target = gen_rtx_SUBREG (TYPE_MODE (type), target, 0);
3282 SUBREG_PROMOTED_VAR_P (target) = 1;
3283 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
3287 /* If size of args is variable or this was a constructor call for a stack
3288 argument, restore saved stack-pointer value. */
3290 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3292 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3293 pending_stack_adjust = old_pending_adj;
3294 stack_arg_under_construction = old_stack_arg_under_construction;
3295 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3296 stack_usage_map = initial_stack_usage_map;
3297 sibcall_failure = 1;
3299 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3301 #ifdef REG_PARM_STACK_SPACE
3304 restore_fixed_argument_area (save_area, argblock,
3305 high_to_save, low_to_save);
3309 /* If we saved any argument areas, restore them. */
3310 for (i = 0; i < num_actuals; i++)
3311 if (args[i].save_area)
3313 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3315 = gen_rtx_MEM (save_mode,
3316 memory_address (save_mode,
3317 XEXP (args[i].stack_slot, 0)));
3319 if (save_mode != BLKmode)
3320 emit_move_insn (stack_area, args[i].save_area);
3322 emit_block_move (stack_area,
3323 validize_mem (args[i].save_area),
3324 GEN_INT (args[i].size.constant),
3328 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3329 stack_usage_map = initial_stack_usage_map;
3332 /* If this was alloca, record the new stack level for nonlocal gotos.
3333 Check for the handler slots since we might not have a save area
3334 for non-local gotos. */
3336 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3337 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3341 /* Free up storage we no longer need. */
3342 for (i = 0; i < num_actuals; ++i)
3343 if (args[i].aligned_regs)
3344 free (args[i].aligned_regs);
3348 /* Undo the fake expand_start_target_temps we did earlier. If
3349 there had been any cleanups created, we've already set
3351 expand_end_target_temps ();
3354 insns = get_insns ();
3359 tail_call_insns = insns;
3361 /* If something prevents making this a sibling call,
3362 zero out the sequence. */
3363 if (sibcall_failure)
3364 tail_call_insns = NULL_RTX;
3365 /* Restore the pending stack adjustment now that we have
3366 finished generating the sibling call sequence. */
3368 pending_stack_adjust = save_pending_stack_adjust;
3369 stack_pointer_delta = save_stack_pointer_delta;
3371 /* Prepare arg structure for next iteration. */
3372 for (i = 0 ; i < num_actuals ; i++)
3375 args[i].aligned_regs = 0;
3379 sbitmap_free (stored_args_map);
3382 normal_call_insns = insns;
3385 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3386 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3387 can happen if the arguments to this function call an inline
3388 function who's expansion contains another CALL_PLACEHOLDER.
3390 If there are any C_Ps in any of these sequences, replace them
3391 with their normal call. */
3393 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3394 if (GET_CODE (insn) == CALL_INSN
3395 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3396 replace_call_placeholder (insn, sibcall_use_normal);
3398 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3399 if (GET_CODE (insn) == CALL_INSN
3400 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3401 replace_call_placeholder (insn, sibcall_use_normal);
3403 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3404 if (GET_CODE (insn) == CALL_INSN
3405 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3406 replace_call_placeholder (insn, sibcall_use_normal);
3408 /* If this was a potential tail recursion site, then emit a
3409 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3410 One of them will be selected later. */
3411 if (tail_recursion_insns || tail_call_insns)
3413 /* The tail recursion label must be kept around. We could expose
3414 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3415 and makes determining true tail recursion sites difficult.
3417 So we set LABEL_PRESERVE_P here, then clear it when we select
3418 one of the call sequences after rtl generation is complete. */
3419 if (tail_recursion_insns)
3420 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3421 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3423 tail_recursion_insns,
3424 tail_recursion_label));
3427 emit_insns (normal_call_insns);
3429 currently_expanding_call--;
3431 /* If this function returns with the stack pointer depressed, ensure
3432 this block saves and restores the stack pointer, show it was
3433 changed, and adjust for any outgoing arg space. */
3434 if (flags & ECF_SP_DEPRESSED)
3436 clear_pending_stack_adjust ();
3437 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3438 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3439 save_stack_pointer ();
3445 /* Returns nonzero if FUN is the symbol for a library function which can
3449 libfunc_nothrow (fun)
3452 if (fun == throw_libfunc
3453 || fun == rethrow_libfunc
3454 || fun == sjthrow_libfunc
3455 || fun == sjpopnthrow_libfunc)
3461 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3462 The RETVAL parameter specifies whether return value needs to be saved, other
3463 parameters are documented in the emit_library_call function bellow. */
3465 emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3470 enum machine_mode outmode;
3474 /* Total size in bytes of all the stack-parms scanned so far. */
3475 struct args_size args_size;
3476 /* Size of arguments before any adjustments (such as rounding). */
3477 struct args_size original_args_size;
3478 register int argnum;
3482 struct args_size alignment_pad;
3484 CUMULATIVE_ARGS args_so_far;
3485 struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
3486 struct args_size offset; struct args_size size; rtx save_area; };
3488 int old_inhibit_defer_pop = inhibit_defer_pop;
3489 rtx call_fusage = 0;
3492 int pcc_struct_value = 0;
3493 int struct_value_size = 0;
3495 int reg_parm_stack_space = 0;
3498 #ifdef REG_PARM_STACK_SPACE
3499 /* Define the boundary of the register parm stack space that needs to be
3501 int low_to_save = -1, high_to_save = 0;
3502 rtx save_area = 0; /* Place that it is saved */
3505 /* Size of the stack reserved for parameter registers. */
3506 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3507 char *initial_stack_usage_map = stack_usage_map;
3509 #ifdef REG_PARM_STACK_SPACE
3510 #ifdef MAYBE_REG_PARM_STACK_SPACE
3511 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3513 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3519 else if (fn_type == 2)
3523 if (libfunc_nothrow (fun))
3524 flags |= ECF_NOTHROW;
3526 #ifdef PREFERRED_STACK_BOUNDARY
3527 /* Ensure current function's preferred stack boundary is at least
3529 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3530 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3533 /* If this kind of value comes back in memory,
3534 decide where in memory it should come back. */
3535 if (outmode != VOIDmode && aggregate_value_p (type_for_mode (outmode, 0)))
3537 #ifdef PCC_STATIC_STRUCT_RETURN
3539 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
3541 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3542 pcc_struct_value = 1;
3544 value = gen_reg_rtx (outmode);
3545 #else /* not PCC_STATIC_STRUCT_RETURN */
3546 struct_value_size = GET_MODE_SIZE (outmode);
3547 if (value != 0 && GET_CODE (value) == MEM)
3550 mem_value = assign_stack_temp (outmode, GET_MODE_SIZE (outmode), 0);
3553 /* This call returns a big structure. */
3554 flags &= ~(ECF_CONST | ECF_PURE);
3557 /* ??? Unfinished: must pass the memory address as an argument. */
3559 /* Copy all the libcall-arguments out of the varargs data
3560 and into a vector ARGVEC.
3562 Compute how to pass each argument. We only support a very small subset
3563 of the full argument passing conventions to limit complexity here since
3564 library functions shouldn't have many args. */
3566 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3567 bzero ((char *) argvec, (nargs + 1) * sizeof (struct arg));
3569 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3571 args_size.constant = 0;
3576 /* Now we are about to start emitting insns that can be deleted
3577 if a libcall is deleted. */
3578 if (flags & (ECF_CONST | ECF_PURE))
3583 /* If there's a structure value address to be passed,
3584 either pass it in the special place, or pass it as an extra argument. */
3585 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3587 rtx addr = XEXP (mem_value, 0);
3590 /* Make sure it is a reasonable operand for a move or push insn. */
3591 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3592 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3593 addr = force_operand (addr, NULL_RTX);
3595 argvec[count].value = addr;
3596 argvec[count].mode = Pmode;
3597 argvec[count].partial = 0;
3599 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3600 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3601 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3605 locate_and_pad_parm (Pmode, NULL_TREE,
3606 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3609 argvec[count].reg != 0,
3611 NULL_TREE, &args_size, &argvec[count].offset,
3612 &argvec[count].size, &alignment_pad);
3615 if (argvec[count].reg == 0 || argvec[count].partial != 0
3616 || reg_parm_stack_space > 0)
3617 args_size.constant += argvec[count].size.constant;
3619 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3624 for (; count < nargs; count++)
3626 rtx val = va_arg (p, rtx);
3627 enum machine_mode mode = va_arg (p, enum machine_mode);
3629 /* We cannot convert the arg value to the mode the library wants here;
3630 must do it earlier where we know the signedness of the arg. */
3632 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3635 /* On some machines, there's no way to pass a float to a library fcn.
3636 Pass it as a double instead. */
3637 #ifdef LIBGCC_NEEDS_DOUBLE
3638 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3639 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3642 /* There's no need to call protect_from_queue, because
3643 either emit_move_insn or emit_push_insn will do that. */
3645 /* Make sure it is a reasonable operand for a move or push insn. */
3646 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3647 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3648 val = force_operand (val, NULL_RTX);
3650 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3651 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3653 /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
3654 be viewed as just an efficiency improvement. */
3655 rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
3656 emit_move_insn (slot, val);
3657 val = force_operand (XEXP (slot, 0), NULL_RTX);
3662 argvec[count].value = val;
3663 argvec[count].mode = mode;
3665 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3667 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3668 argvec[count].partial
3669 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3671 argvec[count].partial = 0;
3674 locate_and_pad_parm (mode, NULL_TREE,
3675 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3678 argvec[count].reg != 0,
3680 NULL_TREE, &args_size, &argvec[count].offset,
3681 &argvec[count].size, &alignment_pad);
3683 if (argvec[count].size.var)
3686 if (reg_parm_stack_space == 0 && argvec[count].partial)
3687 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3689 if (argvec[count].reg == 0 || argvec[count].partial != 0
3690 || reg_parm_stack_space > 0)
3691 args_size.constant += argvec[count].size.constant;
3693 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3696 #ifdef FINAL_REG_PARM_STACK_SPACE
3697 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3700 /* If this machine requires an external definition for library
3701 functions, write one out. */
3702 assemble_external_libcall (fun);
3704 original_args_size = args_size;
3705 #ifdef PREFERRED_STACK_BOUNDARY
3706 args_size.constant = (((args_size.constant
3707 + stack_pointer_delta
3711 - stack_pointer_delta);
3714 args_size.constant = MAX (args_size.constant,
3715 reg_parm_stack_space);
3717 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3718 args_size.constant -= reg_parm_stack_space;
3721 if (args_size.constant > current_function_outgoing_args_size)
3722 current_function_outgoing_args_size = args_size.constant;
3724 if (ACCUMULATE_OUTGOING_ARGS)
3726 /* Since the stack pointer will never be pushed, it is possible for
3727 the evaluation of a parm to clobber something we have already
3728 written to the stack. Since most function calls on RISC machines
3729 do not use the stack, this is uncommon, but must work correctly.
3731 Therefore, we save any area of the stack that was already written
3732 and that we are using. Here we set up to do this by making a new
3733 stack usage map from the old one.
3735 Another approach might be to try to reorder the argument
3736 evaluations to avoid this conflicting stack usage. */
3738 needed = args_size.constant;
3740 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3741 /* Since we will be writing into the entire argument area, the
3742 map must be allocated for its entire size, not just the part that
3743 is the responsibility of the caller. */
3744 needed += reg_parm_stack_space;
3747 #ifdef ARGS_GROW_DOWNWARD
3748 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3751 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3754 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3756 if (initial_highest_arg_in_use)
3757 bcopy (initial_stack_usage_map, stack_usage_map,
3758 initial_highest_arg_in_use);
3760 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3761 bzero (&stack_usage_map[initial_highest_arg_in_use],
3762 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3765 /* The address of the outgoing argument list must not be copied to a
3766 register here, because argblock would be left pointing to the
3767 wrong place after the call to allocate_dynamic_stack_space below.
3770 argblock = virtual_outgoing_args_rtx;
3775 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3778 #ifdef PREFERRED_STACK_BOUNDARY
3779 /* If we push args individually in reverse order, perform stack alignment
3780 before the first push (the last arg). */
3781 if (argblock == 0 && PUSH_ARGS_REVERSED)
3782 anti_adjust_stack (GEN_INT (args_size.constant
3783 - original_args_size.constant));
3786 if (PUSH_ARGS_REVERSED)
3797 #ifdef REG_PARM_STACK_SPACE
3798 if (ACCUMULATE_OUTGOING_ARGS)
3800 /* The argument list is the property of the called routine and it
3801 may clobber it. If the fixed area has been used for previous
3802 parameters, we must save and restore it.
3804 Here we compute the boundary of the that needs to be saved, if any. */
3806 #ifdef ARGS_GROW_DOWNWARD
3807 for (count = 0; count < reg_parm_stack_space + 1; count++)
3809 for (count = 0; count < reg_parm_stack_space; count++)
3812 if (count >= highest_outgoing_arg_in_use
3813 || stack_usage_map[count] == 0)
3816 if (low_to_save == -1)
3817 low_to_save = count;
3819 high_to_save = count;
3822 if (low_to_save >= 0)
3824 int num_to_save = high_to_save - low_to_save + 1;
3825 enum machine_mode save_mode
3826 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3829 /* If we don't have the required alignment, must do this in BLKmode. */
3830 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3831 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3832 save_mode = BLKmode;
3834 #ifdef ARGS_GROW_DOWNWARD
3835 stack_area = gen_rtx_MEM (save_mode,
3836 memory_address (save_mode,
3837 plus_constant (argblock,
3840 stack_area = gen_rtx_MEM (save_mode,
3841 memory_address (save_mode,
3842 plus_constant (argblock,
3845 if (save_mode == BLKmode)
3847 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3848 emit_block_move (validize_mem (save_area), stack_area,
3849 GEN_INT (num_to_save), PARM_BOUNDARY);
3853 save_area = gen_reg_rtx (save_mode);
3854 emit_move_insn (save_area, stack_area);
3860 /* Push the args that need to be pushed. */
3862 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3863 are to be pushed. */
3864 for (count = 0; count < nargs; count++, argnum += inc)
3866 register enum machine_mode mode = argvec[argnum].mode;
3867 register rtx val = argvec[argnum].value;
3868 rtx reg = argvec[argnum].reg;
3869 int partial = argvec[argnum].partial;
3870 int lower_bound = 0, upper_bound = 0, i;
3872 if (! (reg != 0 && partial == 0))
3874 if (ACCUMULATE_OUTGOING_ARGS)
3876 /* If this is being stored into a pre-allocated, fixed-size,
3877 stack area, save any previous data at that location. */
3879 #ifdef ARGS_GROW_DOWNWARD
3880 /* stack_slot is negative, but we want to index stack_usage_map
3881 with positive values. */
3882 upper_bound = -argvec[argnum].offset.constant + 1;
3883 lower_bound = upper_bound - argvec[argnum].size.constant;
3885 lower_bound = argvec[argnum].offset.constant;
3886 upper_bound = lower_bound + argvec[argnum].size.constant;
3889 for (i = lower_bound; i < upper_bound; i++)
3890 if (stack_usage_map[i]
3891 /* Don't store things in the fixed argument area at this
3892 point; it has already been saved. */
3893 && i > reg_parm_stack_space)
3896 if (i != upper_bound)
3898 /* We need to make a save area. See what mode we can make
3900 enum machine_mode save_mode
3901 = mode_for_size (argvec[argnum].size.constant
3909 plus_constant (argblock,
3910 argvec[argnum].offset.constant)));
3911 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3913 emit_move_insn (argvec[argnum].save_area, stack_area);
3917 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
3918 argblock, GEN_INT (argvec[argnum].offset.constant),
3919 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3921 /* Now mark the segment we just used. */
3922 if (ACCUMULATE_OUTGOING_ARGS)
3923 for (i = lower_bound; i < upper_bound; i++)
3924 stack_usage_map[i] = 1;
3930 #ifdef PREFERRED_STACK_BOUNDARY
3931 /* If we pushed args in forward order, perform stack alignment
3932 after pushing the last arg. */
3933 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3934 anti_adjust_stack (GEN_INT (args_size.constant
3935 - original_args_size.constant));
3938 if (PUSH_ARGS_REVERSED)
3943 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
3945 /* Now load any reg parms into their regs. */
3947 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3948 are to be pushed. */
3949 for (count = 0; count < nargs; count++, argnum += inc)
3951 register rtx val = argvec[argnum].value;
3952 rtx reg = argvec[argnum].reg;
3953 int partial = argvec[argnum].partial;
3955 /* Handle calls that pass values in multiple non-contiguous
3956 locations. The PA64 has examples of this for library calls. */
3957 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3958 emit_group_load (reg, val,
3959 GET_MODE_SIZE (GET_MODE (val)),
3960 GET_MODE_ALIGNMENT (GET_MODE (val)));
3961 else if (reg != 0 && partial == 0)
3962 emit_move_insn (reg, val);
3967 /* Any regs containing parms remain in use through the call. */
3968 for (count = 0; count < nargs; count++)
3970 rtx reg = argvec[count].reg;
3971 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3972 use_group_regs (&call_fusage, reg);
3974 use_reg (&call_fusage, reg);
3977 /* Pass the function the address in which to return a structure value. */
3978 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
3980 emit_move_insn (struct_value_rtx,
3982 force_operand (XEXP (mem_value, 0),
3984 if (GET_CODE (struct_value_rtx) == REG)
3985 use_reg (&call_fusage, struct_value_rtx);
3988 /* Don't allow popping to be deferred, since then
3989 cse'ing of library calls could delete a call and leave the pop. */
3991 valreg = (mem_value == 0 && outmode != VOIDmode
3992 ? hard_libcall_value (outmode) : NULL_RTX);
3994 #ifdef PREFERRED_STACK_BOUNDARY
3995 /* Stack must be properly aligned now. */
3996 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4000 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4001 will set inhibit_defer_pop to that value. */
4002 /* The return type is needed to decide how many bytes the function pops.
4003 Signedness plays no role in that, so for simplicity, we pretend it's
4004 always signed. We also assume that the list of arguments passed has
4005 no impact, so we pretend it is unknown. */
4008 get_identifier (XSTR (orgfun, 0)),
4009 build_function_type (outmode == VOIDmode ? void_type_node
4010 : type_for_mode (outmode, 0), NULL_TREE),
4011 original_args_size.constant, args_size.constant,
4013 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4015 old_inhibit_defer_pop + 1, call_fusage, flags);
4017 /* Now restore inhibit_defer_pop to its actual original value. */
4020 /* If call is cse'able, make appropriate pair of reg-notes around it.
4021 Test valreg so we don't crash; may safely ignore `const'
4022 if return type is void. Disable for PARALLEL return values, because
4023 we have no way to move such values into a pseudo register. */
4024 if ((flags & (ECF_CONST | ECF_PURE))
4025 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
4028 rtx temp = gen_reg_rtx (GET_MODE (valreg));
4032 /* Construct an "equal form" for the value which mentions all the
4033 arguments in order as well as the function name. */
4034 for (i = 0; i < nargs; i++)
4035 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4036 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4038 insns = get_insns ();
4041 if (flags & ECF_PURE)
4042 note = gen_rtx_EXPR_LIST (VOIDmode,
4043 gen_rtx_USE (VOIDmode,
4044 gen_rtx_MEM (BLKmode,
4045 gen_rtx_SCRATCH (VOIDmode))), note);
4047 emit_libcall_block (insns, temp, valreg, note);
4051 else if (flags & (ECF_CONST | ECF_PURE))
4053 /* Otherwise, just write out the sequence without a note. */
4054 rtx insns = get_insns ();
4061 /* Copy the value to the right place. */
4062 if (outmode != VOIDmode && retval)
4068 if (value != mem_value)
4069 emit_move_insn (value, mem_value);
4071 else if (value != 0)
4072 emit_move_insn (value, hard_libcall_value (outmode));
4074 value = hard_libcall_value (outmode);
4077 if (ACCUMULATE_OUTGOING_ARGS)
4079 #ifdef REG_PARM_STACK_SPACE
4082 enum machine_mode save_mode = GET_MODE (save_area);
4083 #ifdef ARGS_GROW_DOWNWARD
4085 = gen_rtx_MEM (save_mode,
4086 memory_address (save_mode,
4087 plus_constant (argblock,
4091 = gen_rtx_MEM (save_mode,
4092 memory_address (save_mode,
4093 plus_constant (argblock, low_to_save)));
4095 if (save_mode != BLKmode)
4096 emit_move_insn (stack_area, save_area);
4098 emit_block_move (stack_area, validize_mem (save_area),
4099 GEN_INT (high_to_save - low_to_save + 1),
4104 /* If we saved any argument areas, restore them. */
4105 for (count = 0; count < nargs; count++)
4106 if (argvec[count].save_area)
4108 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4110 = gen_rtx_MEM (save_mode,
4113 plus_constant (argblock,
4114 argvec[count].offset.constant)));
4116 emit_move_insn (stack_area, argvec[count].save_area);
4119 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4120 stack_usage_map = initial_stack_usage_map;
4127 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4128 (emitting the queue unless NO_QUEUE is nonzero),
4129 for a value of mode OUTMODE,
4130 with NARGS different arguments, passed as alternating rtx values
4131 and machine_modes to convert them to.
4132 The rtx values should have been passed through protect_from_queue already.
4134 FN_TYPE will is zero for `normal' calls, one for `const' calls, wich
4135 which will be enclosed in REG_LIBCALL/REG_RETVAL notes and two for `pure'
4136 calls, that are handled like `const' calls with extra
4137 (use (memory (scratch)). */
4140 emit_library_call VPARAMS((rtx orgfun, int fn_type, enum machine_mode outmode,
4143 #ifndef ANSI_PROTOTYPES
4146 enum machine_mode outmode;
4151 VA_START (p, nargs);
4153 #ifndef ANSI_PROTOTYPES
4154 orgfun = va_arg (p, rtx);
4155 fn_type = va_arg (p, int);
4156 outmode = va_arg (p, enum machine_mode);
4157 nargs = va_arg (p, int);
4160 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4165 /* Like emit_library_call except that an extra argument, VALUE,
4166 comes second and says where to store the result.
4167 (If VALUE is zero, this function chooses a convenient way
4168 to return the value.
4170 This function returns an rtx for where the value is to be found.
4171 If VALUE is nonzero, VALUE is returned. */
4174 emit_library_call_value VPARAMS((rtx orgfun, rtx value, int fn_type,
4175 enum machine_mode outmode, int nargs, ...))
4177 #ifndef ANSI_PROTOTYPES
4181 enum machine_mode outmode;
4186 VA_START (p, nargs);
4188 #ifndef ANSI_PROTOTYPES
4189 orgfun = va_arg (p, rtx);
4190 value = va_arg (p, rtx);
4191 fn_type = va_arg (p, int);
4192 outmode = va_arg (p, enum machine_mode);
4193 nargs = va_arg (p, int);
4196 value = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode, nargs, p);
4204 /* Return an rtx which represents a suitable home on the stack
4205 given TYPE, the type of the argument looking for a home.
4206 This is called only for BLKmode arguments.
4208 SIZE is the size needed for this target.
4209 ARGS_ADDR is the address of the bottom of the argument block for this call.
4210 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
4211 if this machine uses push insns. */
4214 target_for_arg (type, size, args_addr, offset)
4218 struct args_size offset;
4221 rtx offset_rtx = ARGS_SIZE_RTX (offset);
4223 /* We do not call memory_address if possible,
4224 because we want to address as close to the stack
4225 as possible. For non-variable sized arguments,
4226 this will be stack-pointer relative addressing. */
4227 if (GET_CODE (offset_rtx) == CONST_INT)
4228 target = plus_constant (args_addr, INTVAL (offset_rtx));
4231 /* I have no idea how to guarantee that this
4232 will work in the presence of register parameters. */
4233 target = gen_rtx_PLUS (Pmode, args_addr, offset_rtx);
4234 target = memory_address (QImode, target);
4237 return gen_rtx_MEM (BLKmode, target);
4241 /* Store a single argument for a function call
4242 into the register or memory area where it must be passed.
4243 *ARG describes the argument value and where to pass it.
4245 ARGBLOCK is the address of the stack-block for all the arguments,
4246 or 0 on a machine where arguments are pushed individually.
4248 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4249 so must be careful about how the stack is used.
4251 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4252 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4253 that we need not worry about saving and restoring the stack.
4255 FNDECL is the declaration of the function we are calling.
4257 Return non-zero if this arg should cause sibcall failure,
4261 store_one_arg (arg, argblock, flags, variable_size,
4262 reg_parm_stack_space)
4263 struct arg_data *arg;
4266 int variable_size ATTRIBUTE_UNUSED;
4267 int reg_parm_stack_space;
4269 register tree pval = arg->tree_value;
4273 int i, lower_bound = 0, upper_bound = 0;
4274 int sibcall_failure = 0;
4276 if (TREE_CODE (pval) == ERROR_MARK)
4279 /* Push a new temporary level for any temporaries we make for
4283 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4285 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4286 save any previous data at that location. */
4287 if (argblock && ! variable_size && arg->stack)
4289 #ifdef ARGS_GROW_DOWNWARD
4290 /* stack_slot is negative, but we want to index stack_usage_map
4291 with positive values. */
4292 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4293 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4297 lower_bound = upper_bound - arg->size.constant;
4299 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4300 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4304 upper_bound = lower_bound + arg->size.constant;
4307 for (i = lower_bound; i < upper_bound; i++)
4308 if (stack_usage_map[i]
4309 /* Don't store things in the fixed argument area at this point;
4310 it has already been saved. */
4311 && i > reg_parm_stack_space)
4314 if (i != upper_bound)
4316 /* We need to make a save area. See what mode we can make it. */
4317 enum machine_mode save_mode
4318 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
4320 = gen_rtx_MEM (save_mode,
4321 memory_address (save_mode,
4322 XEXP (arg->stack_slot, 0)));
4324 if (save_mode == BLKmode)
4326 arg->save_area = assign_stack_temp (BLKmode,
4327 arg->size.constant, 0);
4328 MEM_SET_IN_STRUCT_P (arg->save_area,
4329 AGGREGATE_TYPE_P (TREE_TYPE
4330 (arg->tree_value)));
4331 preserve_temp_slots (arg->save_area);
4332 emit_block_move (validize_mem (arg->save_area), stack_area,
4333 GEN_INT (arg->size.constant),
4338 arg->save_area = gen_reg_rtx (save_mode);
4339 emit_move_insn (arg->save_area, stack_area);
4343 /* Now that we have saved any slots that will be overwritten by this
4344 store, mark all slots this store will use. We must do this before
4345 we actually expand the argument since the expansion itself may
4346 trigger library calls which might need to use the same stack slot. */
4347 if (argblock && ! variable_size && arg->stack)
4348 for (i = lower_bound; i < upper_bound; i++)
4349 stack_usage_map[i] = 1;
4352 /* If this isn't going to be placed on both the stack and in registers,
4353 set up the register and number of words. */
4354 if (! arg->pass_on_stack)
4355 reg = arg->reg, partial = arg->partial;
4357 if (reg != 0 && partial == 0)
4358 /* Being passed entirely in a register. We shouldn't be called in
4362 /* If this arg needs special alignment, don't load the registers
4364 if (arg->n_aligned_regs != 0)
4367 /* If this is being passed partially in a register, we can't evaluate
4368 it directly into its stack slot. Otherwise, we can. */
4369 if (arg->value == 0)
4371 /* stack_arg_under_construction is nonzero if a function argument is
4372 being evaluated directly into the outgoing argument list and
4373 expand_call must take special action to preserve the argument list
4374 if it is called recursively.
4376 For scalar function arguments stack_usage_map is sufficient to
4377 determine which stack slots must be saved and restored. Scalar
4378 arguments in general have pass_on_stack == 0.
4380 If this argument is initialized by a function which takes the
4381 address of the argument (a C++ constructor or a C function
4382 returning a BLKmode structure), then stack_usage_map is
4383 insufficient and expand_call must push the stack around the
4384 function call. Such arguments have pass_on_stack == 1.
4386 Note that it is always safe to set stack_arg_under_construction,
4387 but this generates suboptimal code if set when not needed. */
4389 if (arg->pass_on_stack)
4390 stack_arg_under_construction++;
4392 arg->value = expand_expr (pval,
4394 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4395 ? NULL_RTX : arg->stack,
4398 /* If we are promoting object (or for any other reason) the mode
4399 doesn't agree, convert the mode. */
4401 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4402 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4403 arg->value, arg->unsignedp);
4405 if (arg->pass_on_stack)
4406 stack_arg_under_construction--;
4409 /* Don't allow anything left on stack from computation
4410 of argument to alloca. */
4411 if (flags & ECF_MAY_BE_ALLOCA)
4412 do_pending_stack_adjust ();
4414 if (arg->value == arg->stack)
4416 /* If the value is already in the stack slot, we are done. */
4417 if (current_function_check_memory_usage && GET_CODE (arg->stack) == MEM)
4419 emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
4420 XEXP (arg->stack, 0), Pmode,
4421 ARGS_SIZE_RTX (arg->size),
4422 TYPE_MODE (sizetype),
4423 GEN_INT (MEMORY_USE_RW),
4424 TYPE_MODE (integer_type_node));
4427 else if (arg->mode != BLKmode)
4431 /* Argument is a scalar, not entirely passed in registers.
4432 (If part is passed in registers, arg->partial says how much
4433 and emit_push_insn will take care of putting it there.)
4435 Push it, and if its size is less than the
4436 amount of space allocated to it,
4437 also bump stack pointer by the additional space.
4438 Note that in C the default argument promotions
4439 will prevent such mismatches. */
4441 size = GET_MODE_SIZE (arg->mode);
4442 /* Compute how much space the push instruction will push.
4443 On many machines, pushing a byte will advance the stack
4444 pointer by a halfword. */
4445 #ifdef PUSH_ROUNDING
4446 size = PUSH_ROUNDING (size);
4450 /* Compute how much space the argument should get:
4451 round up to a multiple of the alignment for arguments. */
4452 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4453 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4454 / (PARM_BOUNDARY / BITS_PER_UNIT))
4455 * (PARM_BOUNDARY / BITS_PER_UNIT));
4457 /* This isn't already where we want it on the stack, so put it there.
4458 This can either be done with push or copy insns. */
4459 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX, 0,
4460 partial, reg, used - size, argblock,
4461 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4462 ARGS_SIZE_RTX (arg->alignment_pad));
4466 /* BLKmode, at least partly to be pushed. */
4468 register int excess;
4471 /* Pushing a nonscalar.
4472 If part is passed in registers, PARTIAL says how much
4473 and emit_push_insn will take care of putting it there. */
4475 /* Round its size up to a multiple
4476 of the allocation unit for arguments. */
4478 if (arg->size.var != 0)
4481 size_rtx = ARGS_SIZE_RTX (arg->size);
4485 /* PUSH_ROUNDING has no effect on us, because
4486 emit_push_insn for BLKmode is careful to avoid it. */
4487 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4488 + partial * UNITS_PER_WORD);
4489 size_rtx = expr_size (pval);
4492 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4494 /* emit_push_insn might not work properly if arg->value and
4495 argblock + arg->offset areas overlap. */
4499 if (XEXP (x, 0) == current_function_internal_arg_pointer
4500 || (GET_CODE (XEXP (x, 0)) == PLUS
4501 && XEXP (XEXP (x, 0), 0) ==
4502 current_function_internal_arg_pointer
4503 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4505 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4506 i = INTVAL (XEXP (XEXP (x, 0), 1));
4508 /* expand_call should ensure this */
4509 if (arg->offset.var || GET_CODE (size_rtx) != CONST_INT)
4512 if (arg->offset.constant > i)
4514 if (arg->offset.constant < i + INTVAL (size_rtx))
4515 sibcall_failure = 1;
4517 else if (arg->offset.constant < i)
4519 if (i < arg->offset.constant + INTVAL (size_rtx))
4520 sibcall_failure = 1;
4525 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4526 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg, excess,
4527 argblock, ARGS_SIZE_RTX (arg->offset),
4528 reg_parm_stack_space,
4529 ARGS_SIZE_RTX (arg->alignment_pad));
4533 /* Unless this is a partially-in-register argument, the argument is now
4536 ??? Note that this can change arg->value from arg->stack to
4537 arg->stack_slot and it matters when they are not the same.
4538 It isn't totally clear that this is correct in all cases. */
4540 arg->value = arg->stack_slot;
4542 /* Once we have pushed something, pops can't safely
4543 be deferred during the rest of the arguments. */
4546 /* ANSI doesn't require a sequence point here,
4547 but PCC has one, so this will avoid some problems. */
4550 /* Free any temporary slots made in processing this argument. Show
4551 that we might have taken the address of something and pushed that
4553 preserve_temp_slots (NULL_RTX);
4557 return sibcall_failure;