1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998
3 1999, 2000, 2001 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
36 #include "langhooks.h"
38 #if !defined FUNCTION_OK_FOR_SIBCALL
39 #define FUNCTION_OK_FOR_SIBCALL(DECL) 1
42 /* Decide whether a function's arguments should be processed
43 from first to last or from last to first.
45 They should if the stack and args grow in opposite directions, but
46 only if we have push insns. */
50 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
51 #define PUSH_ARGS_REVERSED PUSH_ARGS
56 #ifndef PUSH_ARGS_REVERSED
57 #define PUSH_ARGS_REVERSED 0
60 #ifndef STACK_POINTER_OFFSET
61 #define STACK_POINTER_OFFSET 0
64 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
65 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
67 /* Data structure and subroutines used within expand_call. */
71 /* Tree node for this argument. */
73 /* Mode for value; TYPE_MODE unless promoted. */
74 enum machine_mode mode;
75 /* Current RTL value for argument, or 0 if it isn't precomputed. */
77 /* Initially-compute RTL value for argument; only for const functions. */
79 /* Register to pass this argument in, 0 if passed on stack, or an
80 PARALLEL if the arg is to be copied into multiple non-contiguous
83 /* Register to pass this argument in when generating tail call sequence.
84 This is not the same register as for normal calls on machines with
87 /* If REG was promoted from the actual mode of the argument expression,
88 indicates whether the promotion is sign- or zero-extended. */
90 /* Number of registers to use. 0 means put the whole arg in registers.
91 Also 0 if not passed in registers. */
93 /* Non-zero if argument must be passed on stack.
94 Note that some arguments may be passed on the stack
95 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
96 pass_on_stack identifies arguments that *cannot* go in registers. */
98 /* Offset of this argument from beginning of stack-args. */
99 struct args_size offset;
100 /* Similar, but offset to the start of the stack slot. Different from
101 OFFSET if this arg pads downward. */
102 struct args_size slot_offset;
103 /* Size of this argument on the stack, rounded up for any padding it gets,
104 parts of the argument passed in registers do not count.
105 If REG_PARM_STACK_SPACE is defined, then register parms
106 are counted here as well. */
107 struct args_size size;
108 /* Location on the stack at which parameter should be stored. The store
109 has already been done if STACK == VALUE. */
111 /* Location on the stack of the start of this argument slot. This can
112 differ from STACK if this arg pads downward. This location is known
113 to be aligned to FUNCTION_ARG_BOUNDARY. */
115 /* Place that this stack area has been saved, if needed. */
117 /* If an argument's alignment does not permit direct copying into registers,
118 copy in smaller-sized pieces into pseudos. These are stored in a
119 block pointed to by this field. The next field says how many
120 word-sized pseudos we made. */
123 /* The amount that the stack pointer needs to be adjusted to
124 force alignment for the next argument. */
125 struct args_size alignment_pad;
128 /* A vector of one char per byte of stack space. A byte if non-zero if
129 the corresponding stack location has been used.
130 This vector is used to prevent a function call within an argument from
131 clobbering any stack already set up. */
132 static char *stack_usage_map;
134 /* Size of STACK_USAGE_MAP. */
135 static int highest_outgoing_arg_in_use;
137 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
138 stack location's tail call argument has been already stored into the stack.
139 This bitmap is used to prevent sibling call optimization if function tries
140 to use parent's incoming argument slots when they have been already
141 overwritten with tail call arguments. */
142 static sbitmap stored_args_map;
144 /* stack_arg_under_construction is nonzero when an argument may be
145 initialized with a constructor call (including a C function that
146 returns a BLKmode struct) and expand_call must take special action
147 to make sure the object being constructed does not overlap the
148 argument list for the constructor call. */
149 int stack_arg_under_construction;
151 static int calls_function PARAMS ((tree, int));
152 static int calls_function_1 PARAMS ((tree, int));
154 /* Nonzero if this is a call to a `const' function. */
156 /* Nonzero if this is a call to a `volatile' function. */
157 #define ECF_NORETURN 2
158 /* Nonzero if this is a call to malloc or a related function. */
160 /* Nonzero if it is plausible that this is a call to alloca. */
161 #define ECF_MAY_BE_ALLOCA 8
162 /* Nonzero if this is a call to a function that won't throw an exception. */
163 #define ECF_NOTHROW 16
164 /* Nonzero if this is a call to setjmp or a related function. */
165 #define ECF_RETURNS_TWICE 32
166 /* Nonzero if this is a call to `longjmp'. */
167 #define ECF_LONGJMP 64
168 /* Nonzero if this is a syscall that makes a new process in the image of
170 #define ECF_FORK_OR_EXEC 128
171 #define ECF_SIBCALL 256
172 /* Nonzero if this is a call to "pure" function (like const function,
173 but may read memory. */
175 /* Nonzero if this is a call to a function that returns with the stack
176 pointer depressed. */
177 #define ECF_SP_DEPRESSED 1024
178 /* Nonzero if this call is known to always return. */
179 #define ECF_ALWAYS_RETURN 2048
180 /* Create libcall block around the call. */
181 #define ECF_LIBCALL_BLOCK 4096
183 static void emit_call_1 PARAMS ((rtx, tree, tree, HOST_WIDE_INT,
184 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
187 static void precompute_register_parameters PARAMS ((int,
190 static int store_one_arg PARAMS ((struct arg_data *, rtx, int, int,
192 static void store_unaligned_arguments_into_pseudos PARAMS ((struct arg_data *,
194 static int finalize_must_preallocate PARAMS ((int, int,
196 struct args_size *));
197 static void precompute_arguments PARAMS ((int, int,
199 static int compute_argument_block_size PARAMS ((int,
202 static void initialize_argument_information PARAMS ((int,
209 static void compute_argument_addresses PARAMS ((struct arg_data *,
211 static rtx rtx_for_function_call PARAMS ((tree, tree));
212 static void load_register_parameters PARAMS ((struct arg_data *,
214 static rtx emit_library_call_value_1 PARAMS ((int, rtx, rtx,
218 static int special_function_p PARAMS ((tree, int));
219 static int flags_from_decl_or_type PARAMS ((tree));
220 static rtx try_to_integrate PARAMS ((tree, tree, rtx,
222 static int check_sibcall_argument_overlap_1 PARAMS ((rtx));
223 static int check_sibcall_argument_overlap PARAMS ((rtx, struct arg_data *));
225 static int combine_pending_stack_adjustment_and_call
226 PARAMS ((int, struct args_size *, int));
228 #ifdef REG_PARM_STACK_SPACE
229 static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
230 static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
233 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
236 If WHICH is 0, return 1 if EXP contains a call to any function.
237 Actually, we only need return 1 if evaluating EXP would require pushing
238 arguments on the stack, but that is too difficult to compute, so we just
239 assume any function call might require the stack. */
241 static tree calls_function_save_exprs;
244 calls_function (exp, which)
250 calls_function_save_exprs = 0;
251 val = calls_function_1 (exp, which);
252 calls_function_save_exprs = 0;
256 /* Recursive function to do the work of above function. */
259 calls_function_1 (exp, which)
264 enum tree_code code = TREE_CODE (exp);
265 int class = TREE_CODE_CLASS (code);
266 int length = first_rtl_op (code);
268 /* If this code is language-specific, we don't know what it will do. */
269 if ((int) code >= NUM_TREE_CODES)
277 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
279 && (TYPE_RETURNS_STACK_DEPRESSED
280 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))))
282 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
283 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
285 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
287 & ECF_MAY_BE_ALLOCA))
296 for (tem = CONSTRUCTOR_ELTS (exp); tem != 0; tem = TREE_CHAIN (tem))
297 if (calls_function_1 (TREE_VALUE (tem), which))
304 if (SAVE_EXPR_RTL (exp) != 0)
306 if (value_member (exp, calls_function_save_exprs))
308 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
309 calls_function_save_exprs);
310 return (TREE_OPERAND (exp, 0) != 0
311 && calls_function_1 (TREE_OPERAND (exp, 0), which));
318 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
319 if (DECL_INITIAL (local) != 0
320 && calls_function_1 (DECL_INITIAL (local), which))
323 for (subblock = BLOCK_SUBBLOCKS (exp);
325 subblock = TREE_CHAIN (subblock))
326 if (calls_function_1 (subblock, which))
332 for (; exp != 0; exp = TREE_CHAIN (exp))
333 if (calls_function_1 (TREE_VALUE (exp), which))
341 /* Only expressions, references, and blocks can contain calls. */
342 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
345 for (i = 0; i < length; i++)
346 if (TREE_OPERAND (exp, i) != 0
347 && calls_function_1 (TREE_OPERAND (exp, i), which))
353 /* Force FUNEXP into a form suitable for the address of a CALL,
354 and return that as an rtx. Also load the static chain register
355 if FNDECL is a nested function.
357 CALL_FUSAGE points to a variable holding the prospective
358 CALL_INSN_FUNCTION_USAGE information. */
361 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen, sibcallp)
368 rtx static_chain_value = 0;
370 funexp = protect_from_queue (funexp, 0);
373 /* Get possible static chain value for nested function in C. */
374 static_chain_value = lookup_static_chain (fndecl);
376 /* Make a valid memory address and copy constants thru pseudo-regs,
377 but not for a constant address if -fno-function-cse. */
378 if (GET_CODE (funexp) != SYMBOL_REF)
379 /* If we are using registers for parameters, force the
380 function address into a register now. */
381 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
382 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
383 : memory_address (FUNCTION_MODE, funexp));
386 #ifndef NO_FUNCTION_CSE
387 if (optimize && ! flag_no_function_cse)
388 #ifdef NO_RECURSIVE_FUNCTION_CSE
389 if (fndecl != current_function_decl)
391 funexp = force_reg (Pmode, funexp);
395 if (static_chain_value != 0)
397 emit_move_insn (static_chain_rtx, static_chain_value);
399 if (GET_CODE (static_chain_rtx) == REG)
400 use_reg (call_fusage, static_chain_rtx);
406 /* Generate instructions to call function FUNEXP,
407 and optionally pop the results.
408 The CALL_INSN is the first insn generated.
410 FNDECL is the declaration node of the function. This is given to the
411 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
413 FUNTYPE is the data type of the function. This is given to the macro
414 RETURN_POPS_ARGS to determine whether this function pops its own args.
415 We used to allow an identifier for library functions, but that doesn't
416 work when the return type is an aggregate type and the calling convention
417 says that the pointer to this aggregate is to be popped by the callee.
419 STACK_SIZE is the number of bytes of arguments on the stack,
420 ROUNDED_STACK_SIZE is that number rounded up to
421 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
422 both to put into the call insn and to generate explicit popping
425 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
426 It is zero if this call doesn't want a structure value.
428 NEXT_ARG_REG is the rtx that results from executing
429 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
430 just after all the args have had their registers assigned.
431 This could be whatever you like, but normally it is the first
432 arg-register beyond those used for args in this call,
433 or 0 if all the arg-registers are used in this call.
434 It is passed on to `gen_call' so you can put this info in the call insn.
436 VALREG is a hard register in which a value is returned,
437 or 0 if the call does not return a value.
439 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
440 the args to this call were processed.
441 We restore `inhibit_defer_pop' to that value.
443 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
444 denote registers used by the called function. */
447 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
448 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
449 call_fusage, ecf_flags, args_so_far)
451 tree fndecl ATTRIBUTE_UNUSED;
452 tree funtype ATTRIBUTE_UNUSED;
453 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
454 HOST_WIDE_INT rounded_stack_size;
455 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
456 rtx next_arg_reg ATTRIBUTE_UNUSED;
458 int old_inhibit_defer_pop;
461 CUMULATIVE_ARGS *args_so_far ATTRIBUTE_UNUSED;
463 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
465 int already_popped = 0;
466 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
467 #if defined (HAVE_call) && defined (HAVE_call_value)
468 rtx struct_value_size_rtx;
469 struct_value_size_rtx = GEN_INT (struct_value_size);
472 #ifdef CALL_POPS_ARGS
473 n_popped += CALL_POPS_ARGS (* args_so_far);
476 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
477 and we don't want to load it into a register as an optimization,
478 because prepare_call_address already did it if it should be done. */
479 if (GET_CODE (funexp) != SYMBOL_REF)
480 funexp = memory_address (FUNCTION_MODE, funexp);
482 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
483 if ((ecf_flags & ECF_SIBCALL)
484 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
485 && (n_popped > 0 || stack_size == 0))
487 rtx n_pop = GEN_INT (n_popped);
490 /* If this subroutine pops its own args, record that in the call insn
491 if possible, for the sake of frame pointer elimination. */
494 pat = GEN_SIBCALL_VALUE_POP (valreg,
495 gen_rtx_MEM (FUNCTION_MODE, funexp),
496 rounded_stack_size_rtx, next_arg_reg,
499 pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
500 rounded_stack_size_rtx, next_arg_reg, n_pop);
502 emit_call_insn (pat);
508 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
509 /* If the target has "call" or "call_value" insns, then prefer them
510 if no arguments are actually popped. If the target does not have
511 "call" or "call_value" insns, then we must use the popping versions
512 even if the call has no arguments to pop. */
513 #if defined (HAVE_call) && defined (HAVE_call_value)
514 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
515 && n_popped > 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
517 if (HAVE_call_pop && HAVE_call_value_pop)
520 rtx n_pop = GEN_INT (n_popped);
523 /* If this subroutine pops its own args, record that in the call insn
524 if possible, for the sake of frame pointer elimination. */
527 pat = GEN_CALL_VALUE_POP (valreg,
528 gen_rtx_MEM (FUNCTION_MODE, funexp),
529 rounded_stack_size_rtx, next_arg_reg, n_pop);
531 pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
532 rounded_stack_size_rtx, next_arg_reg, n_pop);
534 emit_call_insn (pat);
540 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
541 if ((ecf_flags & ECF_SIBCALL)
542 && HAVE_sibcall && HAVE_sibcall_value)
545 emit_call_insn (GEN_SIBCALL_VALUE (valreg,
546 gen_rtx_MEM (FUNCTION_MODE, funexp),
547 rounded_stack_size_rtx,
548 next_arg_reg, NULL_RTX));
550 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
551 rounded_stack_size_rtx, next_arg_reg,
552 struct_value_size_rtx));
557 #if defined (HAVE_call) && defined (HAVE_call_value)
558 if (HAVE_call && HAVE_call_value)
561 emit_call_insn (GEN_CALL_VALUE (valreg,
562 gen_rtx_MEM (FUNCTION_MODE, funexp),
563 rounded_stack_size_rtx, next_arg_reg,
566 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
567 rounded_stack_size_rtx, next_arg_reg,
568 struct_value_size_rtx));
574 /* Find the CALL insn we just emitted. */
575 for (call_insn = get_last_insn ();
576 call_insn && GET_CODE (call_insn) != CALL_INSN;
577 call_insn = PREV_INSN (call_insn))
583 /* Mark memory as used for "pure" function call. */
584 if (ecf_flags & ECF_PURE)
588 gen_rtx_USE (VOIDmode,
589 gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode))),
592 /* Put the register usage information on the CALL. If there is already
593 some usage information, put ours at the end. */
594 if (CALL_INSN_FUNCTION_USAGE (call_insn))
598 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
599 link = XEXP (link, 1))
602 XEXP (link, 1) = call_fusage;
605 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
607 /* If this is a const call, then set the insn's unchanging bit. */
608 if (ecf_flags & (ECF_CONST | ECF_PURE))
609 CONST_OR_PURE_CALL_P (call_insn) = 1;
611 /* If this call can't throw, attach a REG_EH_REGION reg note to that
613 if (ecf_flags & ECF_NOTHROW)
614 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
615 REG_NOTES (call_insn));
617 if (ecf_flags & ECF_NORETURN)
618 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_NORETURN, const0_rtx,
619 REG_NOTES (call_insn));
620 if (ecf_flags & ECF_ALWAYS_RETURN)
621 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN, const0_rtx,
622 REG_NOTES (call_insn));
624 if (ecf_flags & ECF_RETURNS_TWICE)
626 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_SETJMP, const0_rtx,
627 REG_NOTES (call_insn));
628 current_function_calls_setjmp = 1;
631 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
633 /* Restore this now, so that we do defer pops for this call's args
634 if the context of the call as a whole permits. */
635 inhibit_defer_pop = old_inhibit_defer_pop;
640 CALL_INSN_FUNCTION_USAGE (call_insn)
641 = gen_rtx_EXPR_LIST (VOIDmode,
642 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
643 CALL_INSN_FUNCTION_USAGE (call_insn));
644 rounded_stack_size -= n_popped;
645 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
646 stack_pointer_delta -= n_popped;
649 if (!ACCUMULATE_OUTGOING_ARGS)
651 /* If returning from the subroutine does not automatically pop the args,
652 we need an instruction to pop them sooner or later.
653 Perhaps do it now; perhaps just record how much space to pop later.
655 If returning from the subroutine does pop the args, indicate that the
656 stack pointer will be changed. */
658 if (rounded_stack_size != 0)
660 if (ecf_flags & ECF_SP_DEPRESSED)
661 /* Just pretend we did the pop. */
662 stack_pointer_delta -= rounded_stack_size;
663 else if (flag_defer_pop && inhibit_defer_pop == 0
664 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
665 pending_stack_adjust += rounded_stack_size;
667 adjust_stack (rounded_stack_size_rtx);
670 /* When we accumulate outgoing args, we must avoid any stack manipulations.
671 Restore the stack pointer to its original value now. Usually
672 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
673 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
674 popping variants of functions exist as well.
676 ??? We may optimize similar to defer_pop above, but it is
677 probably not worthwhile.
679 ??? It will be worthwhile to enable combine_stack_adjustments even for
682 anti_adjust_stack (GEN_INT (n_popped));
685 /* Determine if the function identified by NAME and FNDECL is one with
686 special properties we wish to know about.
688 For example, if the function might return more than one time (setjmp), then
689 set RETURNS_TWICE to a nonzero value.
691 Similarly set LONGJMP for if the function is in the longjmp family.
693 Set MALLOC for any of the standard memory allocation functions which
694 allocate from the heap.
696 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
697 space from the stack such as alloca. */
700 special_function_p (fndecl, flags)
704 if (! (flags & ECF_MALLOC)
705 && fndecl && DECL_NAME (fndecl)
706 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
707 /* Exclude functions not at the file scope, or not `extern',
708 since they are not the magic functions we would otherwise
710 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
712 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
713 const char *tname = name;
715 /* We assume that alloca will always be called by name. It
716 makes no sense to pass it as a pointer-to-function to
717 anything that does not understand its behavior. */
718 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
720 && ! strcmp (name, "alloca"))
721 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
723 && ! strcmp (name, "__builtin_alloca"))))
724 flags |= ECF_MAY_BE_ALLOCA;
726 /* Disregard prefix _, __ or __x. */
729 if (name[1] == '_' && name[2] == 'x')
731 else if (name[1] == '_')
740 && (! strcmp (tname, "setjmp")
741 || ! strcmp (tname, "setjmp_syscall")))
743 && ! strcmp (tname, "sigsetjmp"))
745 && ! strcmp (tname, "savectx")))
746 flags |= ECF_RETURNS_TWICE;
749 && ! strcmp (tname, "siglongjmp"))
750 flags |= ECF_LONGJMP;
752 else if ((tname[0] == 'q' && tname[1] == 's'
753 && ! strcmp (tname, "qsetjmp"))
754 || (tname[0] == 'v' && tname[1] == 'f'
755 && ! strcmp (tname, "vfork")))
756 flags |= ECF_RETURNS_TWICE;
758 else if (tname[0] == 'l' && tname[1] == 'o'
759 && ! strcmp (tname, "longjmp"))
760 flags |= ECF_LONGJMP;
762 else if ((tname[0] == 'f' && tname[1] == 'o'
763 && ! strcmp (tname, "fork"))
764 /* Linux specific: __clone. check NAME to insist on the
765 leading underscores, to avoid polluting the ISO / POSIX
767 || (name[0] == '_' && name[1] == '_'
768 && ! strcmp (tname, "clone"))
769 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
770 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
772 || ((tname[5] == 'p' || tname[5] == 'e')
773 && tname[6] == '\0'))))
774 flags |= ECF_FORK_OR_EXEC;
776 /* Do not add any more malloc-like functions to this list,
777 instead mark them as malloc functions using the malloc attribute.
778 Note, realloc is not suitable for attribute malloc since
779 it may return the same address across multiple calls.
780 C++ operator new is not suitable because it is not required
781 to return a unique pointer; indeed, the standard placement new
782 just returns its argument. */
783 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl))) == Pmode
784 && (! strcmp (tname, "malloc")
785 || ! strcmp (tname, "calloc")
786 || ! strcmp (tname, "strdup")))
792 /* Return nonzero when tree represent call to longjmp. */
795 setjmp_call_p (fndecl)
798 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
801 /* Detect flags (function attributes) from the function decl or type node. */
804 flags_from_decl_or_type (exp)
809 /* ??? We can't set IS_MALLOC for function types? */
812 type = TREE_TYPE (exp);
814 /* The function exp may have the `malloc' attribute. */
815 if (DECL_P (exp) && DECL_IS_MALLOC (exp))
818 /* The function exp may have the `pure' attribute. */
819 if (DECL_P (exp) && DECL_IS_PURE (exp))
820 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
822 if (TREE_NOTHROW (exp))
823 flags |= ECF_NOTHROW;
826 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
827 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
829 if (TREE_THIS_VOLATILE (exp))
830 flags |= ECF_NORETURN;
832 /* Mark if the function returns with the stack pointer depressed. We
833 cannot consider it pure or constant in that case. */
834 if (TREE_CODE (type) == FUNCTION_TYPE && TYPE_RETURNS_STACK_DEPRESSED (type))
836 flags |= ECF_SP_DEPRESSED;
837 flags &= ~(ECF_PURE | ECF_CONST | ECF_LIBCALL_BLOCK);
843 /* Precompute all register parameters as described by ARGS, storing values
844 into fields within the ARGS array.
846 NUM_ACTUALS indicates the total number elements in the ARGS array.
848 Set REG_PARM_SEEN if we encounter a register parameter. */
851 precompute_register_parameters (num_actuals, args, reg_parm_seen)
853 struct arg_data *args;
860 for (i = 0; i < num_actuals; i++)
861 if (args[i].reg != 0 && ! args[i].pass_on_stack)
865 if (args[i].value == 0)
868 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
870 preserve_temp_slots (args[i].value);
873 /* ANSI doesn't require a sequence point here,
874 but PCC has one, so this will avoid some problems. */
878 /* If we are to promote the function arg to a wider mode,
881 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
883 = convert_modes (args[i].mode,
884 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
885 args[i].value, args[i].unsignedp);
887 /* If the value is expensive, and we are inside an appropriately
888 short loop, put the value into a pseudo and then put the pseudo
891 For small register classes, also do this if this call uses
892 register parameters. This is to avoid reload conflicts while
893 loading the parameters registers. */
895 if ((! (GET_CODE (args[i].value) == REG
896 || (GET_CODE (args[i].value) == SUBREG
897 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
898 && args[i].mode != BLKmode
899 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
900 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
901 || preserve_subexpressions_p ()))
902 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
906 #ifdef REG_PARM_STACK_SPACE
908 /* The argument list is the property of the called routine and it
909 may clobber it. If the fixed area has been used for previous
910 parameters, we must save and restore it. */
913 save_fixed_argument_area (reg_parm_stack_space, argblock,
914 low_to_save, high_to_save)
915 int reg_parm_stack_space;
921 rtx save_area = NULL_RTX;
923 /* Compute the boundary of the that needs to be saved, if any. */
924 #ifdef ARGS_GROW_DOWNWARD
925 for (i = 0; i < reg_parm_stack_space + 1; i++)
927 for (i = 0; i < reg_parm_stack_space; i++)
930 if (i >= highest_outgoing_arg_in_use
931 || stack_usage_map[i] == 0)
934 if (*low_to_save == -1)
940 if (*low_to_save >= 0)
942 int num_to_save = *high_to_save - *low_to_save + 1;
943 enum machine_mode save_mode
944 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
947 /* If we don't have the required alignment, must do this in BLKmode. */
948 if ((*low_to_save & (MIN (GET_MODE_SIZE (save_mode),
949 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
952 #ifdef ARGS_GROW_DOWNWARD
954 = gen_rtx_MEM (save_mode,
955 memory_address (save_mode,
956 plus_constant (argblock,
959 stack_area = gen_rtx_MEM (save_mode,
960 memory_address (save_mode,
961 plus_constant (argblock,
965 set_mem_align (stack_area, PARM_BOUNDARY);
966 if (save_mode == BLKmode)
968 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
969 /* Cannot use emit_block_move here because it can be done by a
970 library call which in turn gets into this place again and deadly
971 infinite recursion happens. */
972 move_by_pieces (validize_mem (save_area), stack_area, num_to_save,
977 save_area = gen_reg_rtx (save_mode);
978 emit_move_insn (save_area, stack_area);
986 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
992 enum machine_mode save_mode = GET_MODE (save_area);
993 #ifdef ARGS_GROW_DOWNWARD
995 = gen_rtx_MEM (save_mode,
996 memory_address (save_mode,
997 plus_constant (argblock,
1001 = gen_rtx_MEM (save_mode,
1002 memory_address (save_mode,
1003 plus_constant (argblock,
1007 if (save_mode != BLKmode)
1008 emit_move_insn (stack_area, save_area);
1010 /* Cannot use emit_block_move here because it can be done by a library
1011 call which in turn gets into this place again and deadly infinite
1012 recursion happens. */
1013 move_by_pieces (stack_area, validize_mem (save_area),
1014 high_to_save - low_to_save + 1, PARM_BOUNDARY);
1016 #endif /* REG_PARM_STACK_SPACE */
1018 /* If any elements in ARGS refer to parameters that are to be passed in
1019 registers, but not in memory, and whose alignment does not permit a
1020 direct copy into registers. Copy the values into a group of pseudos
1021 which we will later copy into the appropriate hard registers.
1023 Pseudos for each unaligned argument will be stored into the array
1024 args[argnum].aligned_regs. The caller is responsible for deallocating
1025 the aligned_regs array if it is nonzero. */
1028 store_unaligned_arguments_into_pseudos (args, num_actuals)
1029 struct arg_data *args;
1034 for (i = 0; i < num_actuals; i++)
1035 if (args[i].reg != 0 && ! args[i].pass_on_stack
1036 && args[i].mode == BLKmode
1037 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1038 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1040 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1041 int big_endian_correction = 0;
1043 args[i].n_aligned_regs
1044 = args[i].partial ? args[i].partial
1045 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1047 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
1048 * args[i].n_aligned_regs);
1050 /* Structures smaller than a word are aligned to the least
1051 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1052 this means we must skip the empty high order bytes when
1053 calculating the bit offset. */
1054 if (BYTES_BIG_ENDIAN
1055 && !FUNCTION_ARG_REG_LITTLE_ENDIAN
1056 && bytes < UNITS_PER_WORD)
1057 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1059 for (j = 0; j < args[i].n_aligned_regs; j++)
1061 rtx reg = gen_reg_rtx (word_mode);
1062 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1063 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1065 args[i].aligned_regs[j] = reg;
1067 /* There is no need to restrict this code to loading items
1068 in TYPE_ALIGN sized hunks. The bitfield instructions can
1069 load up entire word sized registers efficiently.
1071 ??? This may not be needed anymore.
1072 We use to emit a clobber here but that doesn't let later
1073 passes optimize the instructions we emit. By storing 0 into
1074 the register later passes know the first AND to zero out the
1075 bitfield being set in the register is unnecessary. The store
1076 of 0 will be deleted as will at least the first AND. */
1078 emit_move_insn (reg, const0_rtx);
1080 bytes -= bitsize / BITS_PER_UNIT;
1081 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
1082 extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1083 word_mode, word_mode,
1090 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1093 NUM_ACTUALS is the total number of parameters.
1095 N_NAMED_ARGS is the total number of named arguments.
1097 FNDECL is the tree code for the target of this call (if known)
1099 ARGS_SO_FAR holds state needed by the target to know where to place
1102 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1103 for arguments which are passed in registers.
1105 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1106 and may be modified by this routine.
1108 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1109 flags which may may be modified by this routine. */
1112 initialize_argument_information (num_actuals, args, args_size, n_named_args,
1113 actparms, fndecl, args_so_far,
1114 reg_parm_stack_space, old_stack_level,
1115 old_pending_adj, must_preallocate,
1117 int num_actuals ATTRIBUTE_UNUSED;
1118 struct arg_data *args;
1119 struct args_size *args_size;
1120 int n_named_args ATTRIBUTE_UNUSED;
1123 CUMULATIVE_ARGS *args_so_far;
1124 int reg_parm_stack_space;
1125 rtx *old_stack_level;
1126 int *old_pending_adj;
1127 int *must_preallocate;
1130 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1133 /* Count arg position in order args appear. */
1136 struct args_size alignment_pad;
1140 args_size->constant = 0;
1143 /* In this loop, we consider args in the order they are written.
1144 We fill up ARGS from the front or from the back if necessary
1145 so that in any case the first arg to be pushed ends up at the front. */
1147 if (PUSH_ARGS_REVERSED)
1149 i = num_actuals - 1, inc = -1;
1150 /* In this case, must reverse order of args
1151 so that we compute and push the last arg first. */
1158 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1159 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1161 tree type = TREE_TYPE (TREE_VALUE (p));
1163 enum machine_mode mode;
1165 args[i].tree_value = TREE_VALUE (p);
1167 /* Replace erroneous argument with constant zero. */
1168 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1169 args[i].tree_value = integer_zero_node, type = integer_type_node;
1171 /* If TYPE is a transparent union, pass things the way we would
1172 pass the first field of the union. We have already verified that
1173 the modes are the same. */
1174 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1175 type = TREE_TYPE (TYPE_FIELDS (type));
1177 /* Decide where to pass this arg.
1179 args[i].reg is nonzero if all or part is passed in registers.
1181 args[i].partial is nonzero if part but not all is passed in registers,
1182 and the exact value says how many words are passed in registers.
1184 args[i].pass_on_stack is nonzero if the argument must at least be
1185 computed on the stack. It may then be loaded back into registers
1186 if args[i].reg is nonzero.
1188 These decisions are driven by the FUNCTION_... macros and must agree
1189 with those made by function.c. */
1191 /* See if this argument should be passed by invisible reference. */
1192 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1193 && contains_placeholder_p (TYPE_SIZE (type)))
1194 || TREE_ADDRESSABLE (type)
1195 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1196 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1197 type, argpos < n_named_args)
1201 /* If we're compiling a thunk, pass through invisible
1202 references instead of making a copy. */
1203 if (current_function_is_thunk
1204 #ifdef FUNCTION_ARG_CALLEE_COPIES
1205 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1206 type, argpos < n_named_args)
1207 /* If it's in a register, we must make a copy of it too. */
1208 /* ??? Is this a sufficient test? Is there a better one? */
1209 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1210 && REG_P (DECL_RTL (args[i].tree_value)))
1211 && ! TREE_ADDRESSABLE (type))
1215 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1216 new object from the argument. If we are passing by
1217 invisible reference, the callee will do that for us, so we
1218 can strip off the TARGET_EXPR. This is not always safe,
1219 but it is safe in the only case where this is a useful
1220 optimization; namely, when the argument is a plain object.
1221 In that case, the frontend is just asking the backend to
1222 make a bitwise copy of the argument. */
1224 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1225 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1226 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1227 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1229 args[i].tree_value = build1 (ADDR_EXPR,
1230 build_pointer_type (type),
1231 args[i].tree_value);
1232 type = build_pointer_type (type);
1234 else if (TREE_CODE (args[i].tree_value) == TARGET_EXPR)
1236 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1237 We implement this by passing the address of the temporary
1238 rather than expanding it into another allocated slot. */
1239 args[i].tree_value = build1 (ADDR_EXPR,
1240 build_pointer_type (type),
1241 args[i].tree_value);
1242 type = build_pointer_type (type);
1246 /* We make a copy of the object and pass the address to the
1247 function being called. */
1250 if (!COMPLETE_TYPE_P (type)
1251 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1252 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1253 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1254 STACK_CHECK_MAX_VAR_SIZE))))
1256 /* This is a variable-sized object. Make space on the stack
1258 rtx size_rtx = expr_size (TREE_VALUE (p));
1260 if (*old_stack_level == 0)
1262 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1263 *old_pending_adj = pending_stack_adjust;
1264 pending_stack_adjust = 0;
1267 copy = gen_rtx_MEM (BLKmode,
1268 allocate_dynamic_stack_space
1269 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1270 set_mem_attributes (copy, type, 1);
1273 copy = assign_temp (type, 0, 1, 0);
1275 store_expr (args[i].tree_value, copy, 0);
1276 *ecf_flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
1278 args[i].tree_value = build1 (ADDR_EXPR,
1279 build_pointer_type (type),
1280 make_tree (type, copy));
1281 type = build_pointer_type (type);
1285 mode = TYPE_MODE (type);
1286 unsignedp = TREE_UNSIGNED (type);
1288 #ifdef PROMOTE_FUNCTION_ARGS
1289 mode = promote_mode (type, mode, &unsignedp, 1);
1292 args[i].unsignedp = unsignedp;
1293 args[i].mode = mode;
1295 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1296 argpos < n_named_args);
1297 #ifdef FUNCTION_INCOMING_ARG
1298 /* If this is a sibling call and the machine has register windows, the
1299 register window has to be unwinded before calling the routine, so
1300 arguments have to go into the incoming registers. */
1301 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1302 argpos < n_named_args);
1304 args[i].tail_call_reg = args[i].reg;
1307 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1310 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1311 argpos < n_named_args);
1314 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1316 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1317 it means that we are to pass this arg in the register(s) designated
1318 by the PARALLEL, but also to pass it in the stack. */
1319 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1320 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1321 args[i].pass_on_stack = 1;
1323 /* If this is an addressable type, we must preallocate the stack
1324 since we must evaluate the object into its final location.
1326 If this is to be passed in both registers and the stack, it is simpler
1328 if (TREE_ADDRESSABLE (type)
1329 || (args[i].pass_on_stack && args[i].reg != 0))
1330 *must_preallocate = 1;
1332 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1333 we cannot consider this function call constant. */
1334 if (TREE_ADDRESSABLE (type))
1335 *ecf_flags &= ~ECF_LIBCALL_BLOCK;
1337 /* Compute the stack-size of this argument. */
1338 if (args[i].reg == 0 || args[i].partial != 0
1339 || reg_parm_stack_space > 0
1340 || args[i].pass_on_stack)
1341 locate_and_pad_parm (mode, type,
1342 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1347 fndecl, args_size, &args[i].offset,
1348 &args[i].size, &alignment_pad);
1350 #ifndef ARGS_GROW_DOWNWARD
1351 args[i].slot_offset = *args_size;
1354 args[i].alignment_pad = alignment_pad;
1356 /* If a part of the arg was put into registers,
1357 don't include that part in the amount pushed. */
1358 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1359 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1360 / (PARM_BOUNDARY / BITS_PER_UNIT)
1361 * (PARM_BOUNDARY / BITS_PER_UNIT));
1363 /* Update ARGS_SIZE, the total stack space for args so far. */
1365 args_size->constant += args[i].size.constant;
1366 if (args[i].size.var)
1368 ADD_PARM_SIZE (*args_size, args[i].size.var);
1371 /* Since the slot offset points to the bottom of the slot,
1372 we must record it after incrementing if the args grow down. */
1373 #ifdef ARGS_GROW_DOWNWARD
1374 args[i].slot_offset = *args_size;
1376 args[i].slot_offset.constant = -args_size->constant;
1378 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1381 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1382 have been used, etc. */
1384 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1385 argpos < n_named_args);
1389 /* Update ARGS_SIZE to contain the total size for the argument block.
1390 Return the original constant component of the argument block's size.
1392 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1393 for arguments passed in registers. */
1396 compute_argument_block_size (reg_parm_stack_space, args_size,
1397 preferred_stack_boundary)
1398 int reg_parm_stack_space;
1399 struct args_size *args_size;
1400 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1402 int unadjusted_args_size = args_size->constant;
1404 /* For accumulate outgoing args mode we don't need to align, since the frame
1405 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1406 backends from generating misaligned frame sizes. */
1407 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1408 preferred_stack_boundary = STACK_BOUNDARY;
1410 /* Compute the actual size of the argument block required. The variable
1411 and constant sizes must be combined, the size may have to be rounded,
1412 and there may be a minimum required size. */
1416 args_size->var = ARGS_SIZE_TREE (*args_size);
1417 args_size->constant = 0;
1419 preferred_stack_boundary /= BITS_PER_UNIT;
1420 if (preferred_stack_boundary > 1)
1422 /* We don't handle this case yet. To handle it correctly we have
1423 to add the delta, round and subtract the delta.
1424 Currently no machine description requires this support. */
1425 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1427 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1430 if (reg_parm_stack_space > 0)
1433 = size_binop (MAX_EXPR, args_size->var,
1434 ssize_int (reg_parm_stack_space));
1436 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1437 /* The area corresponding to register parameters is not to count in
1438 the size of the block we need. So make the adjustment. */
1440 = size_binop (MINUS_EXPR, args_size->var,
1441 ssize_int (reg_parm_stack_space));
1447 preferred_stack_boundary /= BITS_PER_UNIT;
1448 if (preferred_stack_boundary < 1)
1449 preferred_stack_boundary = 1;
1450 args_size->constant = (((args_size->constant
1451 + stack_pointer_delta
1452 + preferred_stack_boundary - 1)
1453 / preferred_stack_boundary
1454 * preferred_stack_boundary)
1455 - stack_pointer_delta);
1457 args_size->constant = MAX (args_size->constant,
1458 reg_parm_stack_space);
1460 #ifdef MAYBE_REG_PARM_STACK_SPACE
1461 if (reg_parm_stack_space == 0)
1462 args_size->constant = 0;
1465 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1466 args_size->constant -= reg_parm_stack_space;
1469 return unadjusted_args_size;
1472 /* Precompute parameters as needed for a function call.
1474 FLAGS is mask of ECF_* constants.
1476 NUM_ACTUALS is the number of arguments.
1478 ARGS is an array containing information for each argument; this
1479 routine fills in the INITIAL_VALUE and VALUE fields for each
1480 precomputed argument. */
1483 precompute_arguments (flags, num_actuals, args)
1486 struct arg_data *args;
1490 /* If this function call is cse'able, precompute all the parameters.
1491 Note that if the parameter is constructed into a temporary, this will
1492 cause an additional copy because the parameter will be constructed
1493 into a temporary location and then copied into the outgoing arguments.
1494 If a parameter contains a call to alloca and this function uses the
1495 stack, precompute the parameter. */
1497 /* If we preallocated the stack space, and some arguments must be passed
1498 on the stack, then we must precompute any parameter which contains a
1499 function call which will store arguments on the stack.
1500 Otherwise, evaluating the parameter may clobber previous parameters
1501 which have already been stored into the stack. (we have code to avoid
1502 such case by saving the outgoing stack arguments, but it results in
1505 for (i = 0; i < num_actuals; i++)
1506 if ((flags & ECF_LIBCALL_BLOCK)
1507 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1509 enum machine_mode mode;
1511 /* If this is an addressable type, we cannot pre-evaluate it. */
1512 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1516 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1518 /* ANSI doesn't require a sequence point here,
1519 but PCC has one, so this will avoid some problems. */
1522 args[i].initial_value = args[i].value
1523 = protect_from_queue (args[i].value, 0);
1525 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1526 if (mode != args[i].mode)
1529 = convert_modes (args[i].mode, mode,
1530 args[i].value, args[i].unsignedp);
1531 #ifdef PROMOTE_FOR_CALL_ONLY
1532 /* CSE will replace this only if it contains args[i].value
1533 pseudo, so convert it down to the declared mode using
1535 if (GET_CODE (args[i].value) == REG
1536 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1538 args[i].initial_value
1539 = gen_lowpart_SUBREG (mode, args[i].value);
1540 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1541 SUBREG_PROMOTED_UNSIGNED_SET (args[i].initial_value,
1549 /* Given the current state of MUST_PREALLOCATE and information about
1550 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1551 compute and return the final value for MUST_PREALLOCATE. */
1554 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1555 int must_preallocate;
1557 struct arg_data *args;
1558 struct args_size *args_size;
1560 /* See if we have or want to preallocate stack space.
1562 If we would have to push a partially-in-regs parm
1563 before other stack parms, preallocate stack space instead.
1565 If the size of some parm is not a multiple of the required stack
1566 alignment, we must preallocate.
1568 If the total size of arguments that would otherwise create a copy in
1569 a temporary (such as a CALL) is more than half the total argument list
1570 size, preallocation is faster.
1572 Another reason to preallocate is if we have a machine (like the m88k)
1573 where stack alignment is required to be maintained between every
1574 pair of insns, not just when the call is made. However, we assume here
1575 that such machines either do not have push insns (and hence preallocation
1576 would occur anyway) or the problem is taken care of with
1579 if (! must_preallocate)
1581 int partial_seen = 0;
1582 int copy_to_evaluate_size = 0;
1585 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1587 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1589 else if (partial_seen && args[i].reg == 0)
1590 must_preallocate = 1;
1592 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1593 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1594 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1595 || TREE_CODE (args[i].tree_value) == COND_EXPR
1596 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1597 copy_to_evaluate_size
1598 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1601 if (copy_to_evaluate_size * 2 >= args_size->constant
1602 && args_size->constant > 0)
1603 must_preallocate = 1;
1605 return must_preallocate;
1608 /* If we preallocated stack space, compute the address of each argument
1609 and store it into the ARGS array.
1611 We need not ensure it is a valid memory address here; it will be
1612 validized when it is used.
1614 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1617 compute_argument_addresses (args, argblock, num_actuals)
1618 struct arg_data *args;
1624 rtx arg_reg = argblock;
1625 int i, arg_offset = 0;
1627 if (GET_CODE (argblock) == PLUS)
1628 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1630 for (i = 0; i < num_actuals; i++)
1632 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1633 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1636 /* Skip this parm if it will not be passed on the stack. */
1637 if (! args[i].pass_on_stack && args[i].reg != 0)
1640 if (GET_CODE (offset) == CONST_INT)
1641 addr = plus_constant (arg_reg, INTVAL (offset));
1643 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1645 addr = plus_constant (addr, arg_offset);
1646 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1647 set_mem_attributes (args[i].stack,
1648 TREE_TYPE (args[i].tree_value), 1);
1650 if (GET_CODE (slot_offset) == CONST_INT)
1651 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1653 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1655 addr = plus_constant (addr, arg_offset);
1656 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1657 set_mem_attributes (args[i].stack_slot,
1658 TREE_TYPE (args[i].tree_value), 1);
1660 /* Function incoming arguments may overlap with sibling call
1661 outgoing arguments and we cannot allow reordering of reads
1662 from function arguments with stores to outgoing arguments
1663 of sibling calls. */
1664 set_mem_alias_set (args[i].stack, 0);
1665 set_mem_alias_set (args[i].stack_slot, 0);
1670 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1671 in a call instruction.
1673 FNDECL is the tree node for the target function. For an indirect call
1674 FNDECL will be NULL_TREE.
1676 EXP is the CALL_EXPR for this call. */
1679 rtx_for_function_call (fndecl, exp)
1685 /* Get the function to call, in the form of RTL. */
1688 /* If this is the first use of the function, see if we need to
1689 make an external definition for it. */
1690 if (! TREE_USED (fndecl))
1692 assemble_external (fndecl);
1693 TREE_USED (fndecl) = 1;
1696 /* Get a SYMBOL_REF rtx for the function address. */
1697 funexp = XEXP (DECL_RTL (fndecl), 0);
1700 /* Generate an rtx (probably a pseudo-register) for the address. */
1705 = expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1706 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1712 /* Do the register loads required for any wholly-register parms or any
1713 parms which are passed both on the stack and in a register. Their
1714 expressions were already evaluated.
1716 Mark all register-parms as living through the call, putting these USE
1717 insns in the CALL_INSN_FUNCTION_USAGE field. */
1720 load_register_parameters (args, num_actuals, call_fusage, flags)
1721 struct arg_data *args;
1728 #ifdef LOAD_ARGS_REVERSED
1729 for (i = num_actuals - 1; i >= 0; i--)
1731 for (i = 0; i < num_actuals; i++)
1734 rtx reg = ((flags & ECF_SIBCALL)
1735 ? args[i].tail_call_reg : args[i].reg);
1736 int partial = args[i].partial;
1741 /* Set to non-negative if must move a word at a time, even if just
1742 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1743 we just use a normal move insn. This value can be zero if the
1744 argument is a zero size structure with no fields. */
1745 nregs = (partial ? partial
1746 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1747 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1748 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1751 /* Handle calls that pass values in multiple non-contiguous
1752 locations. The Irix 6 ABI has examples of this. */
1754 if (GET_CODE (reg) == PARALLEL)
1755 emit_group_load (reg, args[i].value,
1756 int_size_in_bytes (TREE_TYPE (args[i].tree_value)));
1758 /* If simple case, just do move. If normal partial, store_one_arg
1759 has already loaded the register for us. In all other cases,
1760 load the register(s) from memory. */
1762 else if (nregs == -1)
1763 emit_move_insn (reg, args[i].value);
1765 /* If we have pre-computed the values to put in the registers in
1766 the case of non-aligned structures, copy them in now. */
1768 else if (args[i].n_aligned_regs != 0)
1769 for (j = 0; j < args[i].n_aligned_regs; j++)
1770 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1771 args[i].aligned_regs[j]);
1773 else if (partial == 0 || args[i].pass_on_stack)
1774 move_block_to_reg (REGNO (reg),
1775 validize_mem (args[i].value), nregs,
1778 /* Handle calls that pass values in multiple non-contiguous
1779 locations. The Irix 6 ABI has examples of this. */
1780 if (GET_CODE (reg) == PARALLEL)
1781 use_group_regs (call_fusage, reg);
1782 else if (nregs == -1)
1783 use_reg (call_fusage, reg);
1785 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1790 /* Try to integrate function. See expand_inline_function for documentation
1791 about the parameters. */
1794 try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1800 rtx structure_value_addr;
1805 rtx old_stack_level = 0;
1806 int reg_parm_stack_space = 0;
1808 #ifdef REG_PARM_STACK_SPACE
1809 #ifdef MAYBE_REG_PARM_STACK_SPACE
1810 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1812 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1816 before_call = get_last_insn ();
1818 timevar_push (TV_INTEGRATION);
1820 temp = expand_inline_function (fndecl, actparms, target,
1822 structure_value_addr);
1824 timevar_pop (TV_INTEGRATION);
1826 /* If inlining succeeded, return. */
1827 if (temp != (rtx) (size_t) - 1)
1829 if (ACCUMULATE_OUTGOING_ARGS)
1831 /* If the outgoing argument list must be preserved, push
1832 the stack before executing the inlined function if it
1835 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1836 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1839 if (stack_arg_under_construction || i >= 0)
1842 = before_call ? NEXT_INSN (before_call) : get_insns ();
1843 rtx insn = NULL_RTX, seq;
1845 /* Look for a call in the inline function code.
1846 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1847 nonzero then there is a call and it is not necessary
1848 to scan the insns. */
1850 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1851 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1852 if (GET_CODE (insn) == CALL_INSN)
1857 /* Reserve enough stack space so that the largest
1858 argument list of any function call in the inline
1859 function does not overlap the argument list being
1860 evaluated. This is usually an overestimate because
1861 allocate_dynamic_stack_space reserves space for an
1862 outgoing argument list in addition to the requested
1863 space, but there is no way to ask for stack space such
1864 that an argument list of a certain length can be
1867 Add the stack space reserved for register arguments, if
1868 any, in the inline function. What is really needed is the
1869 largest value of reg_parm_stack_space in the inline
1870 function, but that is not available. Using the current
1871 value of reg_parm_stack_space is wrong, but gives
1872 correct results on all supported machines. */
1874 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1875 + reg_parm_stack_space);
1878 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1879 allocate_dynamic_stack_space (GEN_INT (adjust),
1880 NULL_RTX, BITS_PER_UNIT);
1883 emit_insns_before (seq, first_insn);
1884 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1889 /* If the result is equivalent to TARGET, return TARGET to simplify
1890 checks in store_expr. They can be equivalent but not equal in the
1891 case of a function that returns BLKmode. */
1892 if (temp != target && rtx_equal_p (temp, target))
1897 /* If inlining failed, mark FNDECL as needing to be compiled
1898 separately after all. If function was declared inline,
1900 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1901 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1903 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1904 warning ("called from here");
1906 (*lang_hooks.mark_addressable) (fndecl);
1907 return (rtx) (size_t) - 1;
1910 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1911 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1912 bytes, then we would need to push some additional bytes to pad the
1913 arguments. So, we compute an adjust to the stack pointer for an
1914 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1915 bytes. Then, when the arguments are pushed the stack will be perfectly
1916 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1917 be popped after the call. Returns the adjustment. */
1920 combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1922 preferred_unit_stack_boundary)
1923 int unadjusted_args_size;
1924 struct args_size *args_size;
1925 int preferred_unit_stack_boundary;
1927 /* The number of bytes to pop so that the stack will be
1928 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1929 HOST_WIDE_INT adjustment;
1930 /* The alignment of the stack after the arguments are pushed, if we
1931 just pushed the arguments without adjust the stack here. */
1932 HOST_WIDE_INT unadjusted_alignment;
1934 unadjusted_alignment
1935 = ((stack_pointer_delta + unadjusted_args_size)
1936 % preferred_unit_stack_boundary);
1938 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1939 as possible -- leaving just enough left to cancel out the
1940 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1941 PENDING_STACK_ADJUST is non-negative, and congruent to
1942 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1944 /* Begin by trying to pop all the bytes. */
1945 unadjusted_alignment
1946 = (unadjusted_alignment
1947 - (pending_stack_adjust % preferred_unit_stack_boundary));
1948 adjustment = pending_stack_adjust;
1949 /* Push enough additional bytes that the stack will be aligned
1950 after the arguments are pushed. */
1951 if (preferred_unit_stack_boundary > 1)
1953 if (unadjusted_alignment > 0)
1954 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1956 adjustment += unadjusted_alignment;
1959 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1960 bytes after the call. The right number is the entire
1961 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1962 by the arguments in the first place. */
1964 = pending_stack_adjust - adjustment + unadjusted_args_size;
1969 /* Scan X expression if it does not dereference any argument slots
1970 we already clobbered by tail call arguments (as noted in stored_args_map
1972 Return non-zero if X expression dereferences such argument slots,
1976 check_sibcall_argument_overlap_1 (x)
1987 code = GET_CODE (x);
1991 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1993 else if (GET_CODE (XEXP (x, 0)) == PLUS
1994 && XEXP (XEXP (x, 0), 0) ==
1995 current_function_internal_arg_pointer
1996 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1997 i = INTVAL (XEXP (XEXP (x, 0), 1));
2001 #ifdef ARGS_GROW_DOWNWARD
2002 i = -i - GET_MODE_SIZE (GET_MODE (x));
2005 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
2006 if (i + k < stored_args_map->n_bits
2007 && TEST_BIT (stored_args_map, i + k))
2013 /* Scan all subexpressions. */
2014 fmt = GET_RTX_FORMAT (code);
2015 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2019 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2022 else if (*fmt == 'E')
2024 for (j = 0; j < XVECLEN (x, i); j++)
2025 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2032 /* Scan sequence after INSN if it does not dereference any argument slots
2033 we already clobbered by tail call arguments (as noted in stored_args_map
2034 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2035 Return non-zero if sequence after INSN dereferences such argument slots,
2039 check_sibcall_argument_overlap (insn, arg)
2041 struct arg_data *arg;
2045 if (insn == NULL_RTX)
2046 insn = get_insns ();
2048 insn = NEXT_INSN (insn);
2050 for (; insn; insn = NEXT_INSN (insn))
2052 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2055 #ifdef ARGS_GROW_DOWNWARD
2056 low = -arg->slot_offset.constant - arg->size.constant;
2058 low = arg->slot_offset.constant;
2061 for (high = low + arg->size.constant; low < high; low++)
2062 SET_BIT (stored_args_map, low);
2063 return insn != NULL_RTX;
2066 /* Generate all the code for a function call
2067 and return an rtx for its value.
2068 Store the value in TARGET (specified as an rtx) if convenient.
2069 If the value is stored in TARGET then TARGET is returned.
2070 If IGNORE is nonzero, then we ignore the value of the function call. */
2073 expand_call (exp, target, ignore)
2078 /* Nonzero if we are currently expanding a call. */
2079 static int currently_expanding_call = 0;
2081 /* List of actual parameters. */
2082 tree actparms = TREE_OPERAND (exp, 1);
2083 /* RTX for the function to be called. */
2085 /* Sequence of insns to perform a tail recursive "call". */
2086 rtx tail_recursion_insns = NULL_RTX;
2087 /* Sequence of insns to perform a normal "call". */
2088 rtx normal_call_insns = NULL_RTX;
2089 /* Sequence of insns to perform a tail recursive "call". */
2090 rtx tail_call_insns = NULL_RTX;
2091 /* Data type of the function. */
2093 /* Declaration of the function being called,
2094 or 0 if the function is computed (not known by name). */
2097 int try_tail_call = 1;
2098 int try_tail_recursion = 1;
2101 /* Register in which non-BLKmode value will be returned,
2102 or 0 if no value or if value is BLKmode. */
2104 /* Address where we should return a BLKmode value;
2105 0 if value not BLKmode. */
2106 rtx structure_value_addr = 0;
2107 /* Nonzero if that address is being passed by treating it as
2108 an extra, implicit first parameter. Otherwise,
2109 it is passed by being copied directly into struct_value_rtx. */
2110 int structure_value_addr_parm = 0;
2111 /* Size of aggregate value wanted, or zero if none wanted
2112 or if we are using the non-reentrant PCC calling convention
2113 or expecting the value in registers. */
2114 HOST_WIDE_INT struct_value_size = 0;
2115 /* Nonzero if called function returns an aggregate in memory PCC style,
2116 by returning the address of where to find it. */
2117 int pcc_struct_value = 0;
2119 /* Number of actual parameters in this call, including struct value addr. */
2121 /* Number of named args. Args after this are anonymous ones
2122 and they must all go on the stack. */
2125 /* Vector of information about each argument.
2126 Arguments are numbered in the order they will be pushed,
2127 not the order they are written. */
2128 struct arg_data *args;
2130 /* Total size in bytes of all the stack-parms scanned so far. */
2131 struct args_size args_size;
2132 struct args_size adjusted_args_size;
2133 /* Size of arguments before any adjustments (such as rounding). */
2134 int unadjusted_args_size;
2135 /* Data on reg parms scanned so far. */
2136 CUMULATIVE_ARGS args_so_far;
2137 /* Nonzero if a reg parm has been scanned. */
2139 /* Nonzero if this is an indirect function call. */
2141 /* Nonzero if we must avoid push-insns in the args for this call.
2142 If stack space is allocated for register parameters, but not by the
2143 caller, then it is preallocated in the fixed part of the stack frame.
2144 So the entire argument block must then be preallocated (i.e., we
2145 ignore PUSH_ROUNDING in that case). */
2147 int must_preallocate = !PUSH_ARGS;
2149 /* Size of the stack reserved for parameter registers. */
2150 int reg_parm_stack_space = 0;
2152 /* Address of space preallocated for stack parms
2153 (on machines that lack push insns), or 0 if space not preallocated. */
2156 /* Mask of ECF_ flags. */
2158 /* Nonzero if this is a call to an inline function. */
2159 int is_integrable = 0;
2160 #ifdef REG_PARM_STACK_SPACE
2161 /* Define the boundary of the register parm stack space that needs to be
2163 int low_to_save = -1, high_to_save;
2164 rtx save_area = 0; /* Place that it is saved */
2167 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2168 char *initial_stack_usage_map = stack_usage_map;
2169 int old_stack_arg_under_construction = 0;
2171 rtx old_stack_level = 0;
2172 int old_pending_adj = 0;
2173 int old_inhibit_defer_pop = inhibit_defer_pop;
2174 int old_stack_allocated;
2176 tree p = TREE_OPERAND (exp, 0);
2178 /* The alignment of the stack, in bits. */
2179 HOST_WIDE_INT preferred_stack_boundary;
2180 /* The alignment of the stack, in bytes. */
2181 HOST_WIDE_INT preferred_unit_stack_boundary;
2183 /* See if this is "nothrow" function call. */
2184 if (TREE_NOTHROW (exp))
2185 flags |= ECF_NOTHROW;
2187 /* See if we can find a DECL-node for the actual function.
2188 As a result, decide whether this is a call to an integrable function. */
2190 fndecl = get_callee_fndecl (exp);
2194 && fndecl != current_function_decl
2195 && DECL_INLINE (fndecl)
2196 && DECL_SAVED_INSNS (fndecl)
2197 && DECL_SAVED_INSNS (fndecl)->inlinable)
2199 else if (! TREE_ADDRESSABLE (fndecl))
2201 /* In case this function later becomes inlinable,
2202 record that there was already a non-inline call to it.
2204 Use abstraction instead of setting TREE_ADDRESSABLE
2206 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2209 warning_with_decl (fndecl, "can't inline call to `%s'");
2210 warning ("called from here");
2212 (*lang_hooks.mark_addressable) (fndecl);
2215 flags |= flags_from_decl_or_type (fndecl);
2218 /* If we don't have specific function to call, see if we have a
2219 attributes set in the type. */
2221 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2223 #ifdef REG_PARM_STACK_SPACE
2224 #ifdef MAYBE_REG_PARM_STACK_SPACE
2225 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2227 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2231 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2232 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2233 must_preallocate = 1;
2236 /* Warn if this value is an aggregate type,
2237 regardless of which calling convention we are using for it. */
2238 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2239 warning ("function call has aggregate value");
2241 /* Set up a place to return a structure. */
2243 /* Cater to broken compilers. */
2244 if (aggregate_value_p (exp))
2246 /* This call returns a big structure. */
2247 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
2249 #ifdef PCC_STATIC_STRUCT_RETURN
2251 pcc_struct_value = 1;
2252 /* Easier than making that case work right. */
2255 /* In case this is a static function, note that it has been
2257 if (! TREE_ADDRESSABLE (fndecl))
2258 (*lang_hooks.mark_addressable) (fndecl);
2262 #else /* not PCC_STATIC_STRUCT_RETURN */
2264 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2266 if (target && GET_CODE (target) == MEM)
2267 structure_value_addr = XEXP (target, 0);
2270 /* For variable-sized objects, we must be called with a target
2271 specified. If we were to allocate space on the stack here,
2272 we would have no way of knowing when to free it. */
2273 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2275 mark_temp_addr_taken (d);
2276 structure_value_addr = XEXP (d, 0);
2280 #endif /* not PCC_STATIC_STRUCT_RETURN */
2283 /* If called function is inline, try to integrate it. */
2287 rtx temp = try_to_integrate (fndecl, actparms, target,
2288 ignore, TREE_TYPE (exp),
2289 structure_value_addr);
2290 if (temp != (rtx) (size_t) - 1)
2294 /* Figure out the amount to which the stack should be aligned. */
2295 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2297 /* Operand 0 is a pointer-to-function; get the type of the function. */
2298 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
2299 if (! POINTER_TYPE_P (funtype))
2301 funtype = TREE_TYPE (funtype);
2303 /* See if this is a call to a function that can return more than once
2304 or a call to longjmp or malloc. */
2305 flags |= special_function_p (fndecl, flags);
2307 if (flags & ECF_MAY_BE_ALLOCA)
2308 current_function_calls_alloca = 1;
2310 /* If struct_value_rtx is 0, it means pass the address
2311 as if it were an extra parameter. */
2312 if (structure_value_addr && struct_value_rtx == 0)
2314 /* If structure_value_addr is a REG other than
2315 virtual_outgoing_args_rtx, we can use always use it. If it
2316 is not a REG, we must always copy it into a register.
2317 If it is virtual_outgoing_args_rtx, we must copy it to another
2318 register in some cases. */
2319 rtx temp = (GET_CODE (structure_value_addr) != REG
2320 || (ACCUMULATE_OUTGOING_ARGS
2321 && stack_arg_under_construction
2322 && structure_value_addr == virtual_outgoing_args_rtx)
2323 ? copy_addr_to_reg (structure_value_addr)
2324 : structure_value_addr);
2327 = tree_cons (error_mark_node,
2328 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2331 structure_value_addr_parm = 1;
2334 /* Count the arguments and set NUM_ACTUALS. */
2335 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2338 /* Compute number of named args.
2339 Normally, don't include the last named arg if anonymous args follow.
2340 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2341 (If no anonymous args follow, the result of list_length is actually
2342 one too large. This is harmless.)
2344 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2345 zero, this machine will be able to place unnamed args that were
2346 passed in registers into the stack. So treat all args as named.
2347 This allows the insns emitting for a specific argument list to be
2348 independent of the function declaration.
2350 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2351 reliable way to pass unnamed args in registers, so we must force
2352 them into memory. */
2354 if ((STRICT_ARGUMENT_NAMING
2355 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2356 && TYPE_ARG_TYPES (funtype) != 0)
2358 = (list_length (TYPE_ARG_TYPES (funtype))
2359 /* Don't include the last named arg. */
2360 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2361 /* Count the struct value address, if it is passed as a parm. */
2362 + structure_value_addr_parm);
2364 /* If we know nothing, treat all args as named. */
2365 n_named_args = num_actuals;
2367 /* Start updating where the next arg would go.
2369 On some machines (such as the PA) indirect calls have a different
2370 calling convention than normal calls. The last argument in
2371 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2373 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
2375 /* Make a vector to hold all the information about each arg. */
2376 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
2377 memset ((char *) args, 0, num_actuals * sizeof (struct arg_data));
2379 /* Build up entries in the ARGS array, compute the size of the
2380 arguments into ARGS_SIZE, etc. */
2381 initialize_argument_information (num_actuals, args, &args_size,
2382 n_named_args, actparms, fndecl,
2383 &args_so_far, reg_parm_stack_space,
2384 &old_stack_level, &old_pending_adj,
2385 &must_preallocate, &flags);
2389 /* If this function requires a variable-sized argument list, don't
2390 try to make a cse'able block for this call. We may be able to
2391 do this eventually, but it is too complicated to keep track of
2392 what insns go in the cse'able block and which don't. */
2394 flags &= ~ECF_LIBCALL_BLOCK;
2395 must_preallocate = 1;
2398 /* Now make final decision about preallocating stack space. */
2399 must_preallocate = finalize_must_preallocate (must_preallocate,
2403 /* If the structure value address will reference the stack pointer, we
2404 must stabilize it. We don't need to do this if we know that we are
2405 not going to adjust the stack pointer in processing this call. */
2407 if (structure_value_addr
2408 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2409 || reg_mentioned_p (virtual_outgoing_args_rtx,
2410 structure_value_addr))
2412 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2413 structure_value_addr = copy_to_reg (structure_value_addr);
2415 /* Tail calls can make things harder to debug, and we're traditionally
2416 pushed these optimizations into -O2. Don't try if we're already
2417 expanding a call, as that means we're an argument. Don't try if
2418 there's cleanups, as we know there's code to follow the call.
2420 If rtx_equal_function_value_matters is false, that means we've
2421 finished with regular parsing. Which means that some of the
2422 machinery we use to generate tail-calls is no longer in place.
2423 This is most often true of sjlj-exceptions, which we couldn't
2424 tail-call to anyway. */
2426 if (currently_expanding_call++ != 0
2427 || !flag_optimize_sibling_calls
2428 || !rtx_equal_function_value_matters
2429 || any_pending_cleanups (1)
2431 try_tail_call = try_tail_recursion = 0;
2433 /* Tail recursion fails, when we are not dealing with recursive calls. */
2434 if (!try_tail_recursion
2435 || TREE_CODE (TREE_OPERAND (exp, 0)) != ADDR_EXPR
2436 || TREE_OPERAND (TREE_OPERAND (exp, 0), 0) != current_function_decl)
2437 try_tail_recursion = 0;
2439 /* Rest of purposes for tail call optimizations to fail. */
2441 #ifdef HAVE_sibcall_epilogue
2442 !HAVE_sibcall_epilogue
2447 /* Doing sibling call optimization needs some work, since
2448 structure_value_addr can be allocated on the stack.
2449 It does not seem worth the effort since few optimizable
2450 sibling calls will return a structure. */
2451 || structure_value_addr != NULL_RTX
2452 /* If the register holding the address is a callee saved
2453 register, then we lose. We have no way to prevent that,
2454 so we only allow calls to named functions. */
2455 /* ??? This could be done by having the insn constraints
2456 use a register class that is all call-clobbered. Any
2457 reload insns generated to fix things up would appear
2458 before the sibcall_epilogue. */
2459 || fndecl == NULL_TREE
2460 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP))
2461 || TREE_THIS_VOLATILE (fndecl)
2462 || !FUNCTION_OK_FOR_SIBCALL (fndecl)
2463 /* If this function requires more stack slots than the current
2464 function, we cannot change it into a sibling call. */
2465 || args_size.constant > current_function_args_size
2466 /* If the callee pops its own arguments, then it must pop exactly
2467 the same number of arguments as the current function. */
2468 || RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2469 != RETURN_POPS_ARGS (current_function_decl,
2470 TREE_TYPE (current_function_decl),
2471 current_function_args_size))
2474 if (try_tail_call || try_tail_recursion)
2477 actparms = NULL_TREE;
2478 /* Ok, we're going to give the tail call the old college try.
2479 This means we're going to evaluate the function arguments
2480 up to three times. There are two degrees of badness we can
2481 encounter, those that can be unsaved and those that can't.
2482 (See unsafe_for_reeval commentary for details.)
2484 Generate a new argument list. Pass safe arguments through
2485 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2486 For hard badness, evaluate them now and put their resulting
2487 rtx in a temporary VAR_DECL.
2489 initialize_argument_information has ordered the array for the
2490 order to be pushed, and we must remember this when reconstructing
2491 the original argument order. */
2493 if (PUSH_ARGS_REVERSED)
2502 i = num_actuals - 1;
2506 for (; i != end; i += inc)
2508 switch (unsafe_for_reeval (args[i].tree_value))
2513 case 1: /* Mildly unsafe. */
2514 args[i].tree_value = unsave_expr (args[i].tree_value);
2517 case 2: /* Wildly unsafe. */
2519 tree var = build_decl (VAR_DECL, NULL_TREE,
2520 TREE_TYPE (args[i].tree_value));
2522 expand_expr (args[i].tree_value, NULL_RTX,
2523 VOIDmode, EXPAND_NORMAL));
2524 args[i].tree_value = var;
2531 /* We need to build actparms for optimize_tail_recursion. We can
2532 safely trash away TREE_PURPOSE, since it is unused by this
2534 if (try_tail_recursion)
2535 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2537 /* Expanding one of those dangerous arguments could have added
2538 cleanups, but otherwise give it a whirl. */
2539 if (any_pending_cleanups (1))
2540 try_tail_call = try_tail_recursion = 0;
2543 /* Generate a tail recursion sequence when calling ourselves. */
2545 if (try_tail_recursion)
2547 /* We want to emit any pending stack adjustments before the tail
2548 recursion "call". That way we know any adjustment after the tail
2549 recursion call can be ignored if we indeed use the tail recursion
2551 int save_pending_stack_adjust = pending_stack_adjust;
2552 int save_stack_pointer_delta = stack_pointer_delta;
2554 /* Emit any queued insns now; otherwise they would end up in
2555 only one of the alternates. */
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"),
2599 /* Ensure current function's preferred stack boundary is at least
2600 what we need. We don't have to increase alignment for recursive
2602 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2603 && fndecl != current_function_decl)
2604 cfun->preferred_stack_boundary = preferred_stack_boundary;
2606 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2608 function_call_count++;
2610 /* We want to make two insn chains; one for a sibling call, the other
2611 for a normal call. We will select one of the two chains after
2612 initial RTL generation is complete. */
2613 for (pass = 0; pass < 2; pass++)
2615 int sibcall_failure = 0;
2616 /* We want to emit any pending stack adjustments before the tail
2617 recursion "call". That way we know any adjustment after the tail
2618 recursion call can be ignored if we indeed use the tail recursion
2620 int save_pending_stack_adjust = 0;
2621 int save_stack_pointer_delta = 0;
2623 rtx before_call, next_arg_reg;
2627 if (! try_tail_call)
2630 /* Emit any queued insns now; otherwise they would end up in
2631 only one of the alternates. */
2634 /* State variables we need to save and restore between
2636 save_pending_stack_adjust = pending_stack_adjust;
2637 save_stack_pointer_delta = stack_pointer_delta;
2640 flags &= ~ECF_SIBCALL;
2642 flags |= ECF_SIBCALL;
2644 /* Other state variables that we must reinitialize each time
2645 through the loop (that are not initialized by the loop itself). */
2649 /* Start a new sequence for the normal call case.
2651 From this point on, if the sibling call fails, we want to set
2652 sibcall_failure instead of continuing the loop. */
2657 /* We know at this point that there are not currently any
2658 pending cleanups. If, however, in the process of evaluating
2659 the arguments we were to create some, we'll need to be
2660 able to get rid of them. */
2661 expand_start_target_temps ();
2664 /* Don't let pending stack adjusts add up to too much.
2665 Also, do all pending adjustments now if there is any chance
2666 this might be a call to alloca or if we are expanding a sibling
2667 call sequence or if we are calling a function that is to return
2668 with stack pointer depressed. */
2669 if (pending_stack_adjust >= 32
2670 || (pending_stack_adjust > 0
2671 && (flags & (ECF_MAY_BE_ALLOCA | ECF_SP_DEPRESSED)))
2673 do_pending_stack_adjust ();
2675 /* When calling a const function, we must pop the stack args right away,
2676 so that the pop is deleted or moved with the call. */
2677 if (pass && (flags & ECF_LIBCALL_BLOCK))
2680 #ifdef FINAL_REG_PARM_STACK_SPACE
2681 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2684 /* Precompute any arguments as needed. */
2686 precompute_arguments (flags, num_actuals, args);
2688 /* Now we are about to start emitting insns that can be deleted
2689 if a libcall is deleted. */
2690 if (pass && (flags & (ECF_LIBCALL_BLOCK | ECF_MALLOC)))
2693 adjusted_args_size = args_size;
2694 /* Compute the actual size of the argument block required. The variable
2695 and constant sizes must be combined, the size may have to be rounded,
2696 and there may be a minimum required size. When generating a sibcall
2697 pattern, do not round up, since we'll be re-using whatever space our
2699 unadjusted_args_size
2700 = compute_argument_block_size (reg_parm_stack_space,
2701 &adjusted_args_size,
2703 : preferred_stack_boundary));
2705 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2707 /* The argument block when performing a sibling call is the
2708 incoming argument block. */
2711 argblock = virtual_incoming_args_rtx;
2712 stored_args_map = sbitmap_alloc (args_size.constant);
2713 sbitmap_zero (stored_args_map);
2716 /* If we have no actual push instructions, or shouldn't use them,
2717 make space for all args right now. */
2718 else if (adjusted_args_size.var != 0)
2720 if (old_stack_level == 0)
2722 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2723 old_pending_adj = pending_stack_adjust;
2724 pending_stack_adjust = 0;
2725 /* stack_arg_under_construction says whether a stack arg is
2726 being constructed at the old stack level. Pushing the stack
2727 gets a clean outgoing argument block. */
2728 old_stack_arg_under_construction = stack_arg_under_construction;
2729 stack_arg_under_construction = 0;
2731 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2735 /* Note that we must go through the motions of allocating an argument
2736 block even if the size is zero because we may be storing args
2737 in the area reserved for register arguments, which may be part of
2740 int needed = adjusted_args_size.constant;
2742 /* Store the maximum argument space used. It will be pushed by
2743 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2746 if (needed > current_function_outgoing_args_size)
2747 current_function_outgoing_args_size = needed;
2749 if (must_preallocate)
2751 if (ACCUMULATE_OUTGOING_ARGS)
2753 /* Since the stack pointer will never be pushed, it is
2754 possible for the evaluation of a parm to clobber
2755 something we have already written to the stack.
2756 Since most function calls on RISC machines do not use
2757 the stack, this is uncommon, but must work correctly.
2759 Therefore, we save any area of the stack that was already
2760 written and that we are using. Here we set up to do this
2761 by making a new stack usage map from the old one. The
2762 actual save will be done by store_one_arg.
2764 Another approach might be to try to reorder the argument
2765 evaluations to avoid this conflicting stack usage. */
2767 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2768 /* Since we will be writing into the entire argument area,
2769 the map must be allocated for its entire size, not just
2770 the part that is the responsibility of the caller. */
2771 needed += reg_parm_stack_space;
2774 #ifdef ARGS_GROW_DOWNWARD
2775 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2778 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2782 = (char *) alloca (highest_outgoing_arg_in_use);
2784 if (initial_highest_arg_in_use)
2785 memcpy (stack_usage_map, initial_stack_usage_map,
2786 initial_highest_arg_in_use);
2788 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2789 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2790 (highest_outgoing_arg_in_use
2791 - initial_highest_arg_in_use));
2794 /* The address of the outgoing argument list must not be
2795 copied to a register here, because argblock would be left
2796 pointing to the wrong place after the call to
2797 allocate_dynamic_stack_space below. */
2799 argblock = virtual_outgoing_args_rtx;
2803 if (inhibit_defer_pop == 0)
2805 /* Try to reuse some or all of the pending_stack_adjust
2806 to get this space. */
2808 = (combine_pending_stack_adjustment_and_call
2809 (unadjusted_args_size,
2810 &adjusted_args_size,
2811 preferred_unit_stack_boundary));
2813 /* combine_pending_stack_adjustment_and_call computes
2814 an adjustment before the arguments are allocated.
2815 Account for them and see whether or not the stack
2816 needs to go up or down. */
2817 needed = unadjusted_args_size - needed;
2821 /* We're releasing stack space. */
2822 /* ??? We can avoid any adjustment at all if we're
2823 already aligned. FIXME. */
2824 pending_stack_adjust = -needed;
2825 do_pending_stack_adjust ();
2829 /* We need to allocate space. We'll do that in
2830 push_block below. */
2831 pending_stack_adjust = 0;
2834 /* Special case this because overhead of `push_block' in
2835 this case is non-trivial. */
2837 argblock = virtual_outgoing_args_rtx;
2839 argblock = push_block (GEN_INT (needed), 0, 0);
2841 /* We only really need to call `copy_to_reg' in the case
2842 where push insns are going to be used to pass ARGBLOCK
2843 to a function call in ARGS. In that case, the stack
2844 pointer changes value from the allocation point to the
2845 call point, and hence the value of
2846 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2847 as well always do it. */
2848 argblock = copy_to_reg (argblock);
2850 /* The save/restore code in store_one_arg handles all
2851 cases except one: a constructor call (including a C
2852 function returning a BLKmode struct) to initialize
2854 if (stack_arg_under_construction)
2856 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2857 rtx push_size = GEN_INT (reg_parm_stack_space
2858 + adjusted_args_size.constant);
2860 rtx push_size = GEN_INT (adjusted_args_size.constant);
2862 if (old_stack_level == 0)
2864 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2866 old_pending_adj = pending_stack_adjust;
2867 pending_stack_adjust = 0;
2868 /* stack_arg_under_construction says whether a stack
2869 arg is being constructed at the old stack level.
2870 Pushing the stack gets a clean outgoing argument
2872 old_stack_arg_under_construction
2873 = stack_arg_under_construction;
2874 stack_arg_under_construction = 0;
2875 /* Make a new map for the new argument list. */
2876 stack_usage_map = (char *)
2877 alloca (highest_outgoing_arg_in_use);
2878 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2879 highest_outgoing_arg_in_use = 0;
2881 allocate_dynamic_stack_space (push_size, NULL_RTX,
2884 /* If argument evaluation might modify the stack pointer,
2885 copy the address of the argument list to a register. */
2886 for (i = 0; i < num_actuals; i++)
2887 if (args[i].pass_on_stack)
2889 argblock = copy_addr_to_reg (argblock);
2896 compute_argument_addresses (args, argblock, num_actuals);
2898 /* If we push args individually in reverse order, perform stack alignment
2899 before the first push (the last arg). */
2900 if (PUSH_ARGS_REVERSED && argblock == 0
2901 && adjusted_args_size.constant != unadjusted_args_size)
2903 /* When the stack adjustment is pending, we get better code
2904 by combining the adjustments. */
2905 if (pending_stack_adjust
2906 && ! (flags & ECF_LIBCALL_BLOCK)
2907 && ! inhibit_defer_pop)
2909 pending_stack_adjust
2910 = (combine_pending_stack_adjustment_and_call
2911 (unadjusted_args_size,
2912 &adjusted_args_size,
2913 preferred_unit_stack_boundary));
2914 do_pending_stack_adjust ();
2916 else if (argblock == 0)
2917 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2918 - unadjusted_args_size));
2920 /* Now that the stack is properly aligned, pops can't safely
2921 be deferred during the evaluation of the arguments. */
2924 funexp = rtx_for_function_call (fndecl, exp);
2926 /* Figure out the register where the value, if any, will come back. */
2928 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2929 && ! structure_value_addr)
2931 if (pcc_struct_value)
2932 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2933 fndecl, (pass == 0));
2935 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2938 /* Precompute all register parameters. It isn't safe to compute anything
2939 once we have started filling any specific hard regs. */
2940 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2942 #ifdef REG_PARM_STACK_SPACE
2943 /* Save the fixed argument area if it's part of the caller's frame and
2944 is clobbered by argument setup for this call. */
2945 if (ACCUMULATE_OUTGOING_ARGS && pass)
2946 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2947 &low_to_save, &high_to_save);
2950 /* Now store (and compute if necessary) all non-register parms.
2951 These come before register parms, since they can require block-moves,
2952 which could clobber the registers used for register parms.
2953 Parms which have partial registers are not stored here,
2954 but we do preallocate space here if they want that. */
2956 for (i = 0; i < num_actuals; i++)
2957 if (args[i].reg == 0 || args[i].pass_on_stack)
2959 rtx before_arg = get_last_insn ();
2961 if (store_one_arg (&args[i], argblock, flags,
2962 adjusted_args_size.var != 0,
2963 reg_parm_stack_space)
2965 && check_sibcall_argument_overlap (before_arg,
2967 sibcall_failure = 1;
2970 /* If we have a parm that is passed in registers but not in memory
2971 and whose alignment does not permit a direct copy into registers,
2972 make a group of pseudos that correspond to each register that we
2974 if (STRICT_ALIGNMENT)
2975 store_unaligned_arguments_into_pseudos (args, num_actuals);
2977 /* Now store any partially-in-registers parm.
2978 This is the last place a block-move can happen. */
2980 for (i = 0; i < num_actuals; i++)
2981 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2983 rtx before_arg = get_last_insn ();
2985 if (store_one_arg (&args[i], argblock, flags,
2986 adjusted_args_size.var != 0,
2987 reg_parm_stack_space)
2989 && check_sibcall_argument_overlap (before_arg,
2991 sibcall_failure = 1;
2994 /* If we pushed args in forward order, perform stack alignment
2995 after pushing the last arg. */
2996 if (!PUSH_ARGS_REVERSED && argblock == 0)
2997 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2998 - unadjusted_args_size));
3000 /* If register arguments require space on the stack and stack space
3001 was not preallocated, allocate stack space here for arguments
3002 passed in registers. */
3003 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3004 if (!ACCUMULATE_OUTGOING_ARGS
3005 && must_preallocate == 0 && reg_parm_stack_space > 0)
3006 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3009 /* Pass the function the address in which to return a
3011 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3013 emit_move_insn (struct_value_rtx,
3015 force_operand (structure_value_addr,
3018 if (GET_CODE (struct_value_rtx) == REG)
3019 use_reg (&call_fusage, struct_value_rtx);
3022 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3023 reg_parm_seen, pass == 0);
3025 load_register_parameters (args, num_actuals, &call_fusage, flags);
3027 /* Perform postincrements before actually calling the function. */
3030 /* Save a pointer to the last insn before the call, so that we can
3031 later safely search backwards to find the CALL_INSN. */
3032 before_call = get_last_insn ();
3034 /* Set up next argument register. For sibling calls on machines
3035 with register windows this should be the incoming register. */
3036 #ifdef FUNCTION_INCOMING_ARG
3038 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3042 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3045 /* All arguments and registers used for the call must be set up by
3048 /* Stack must be properly aligned now. */
3049 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3052 /* Generate the actual call instruction. */
3053 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3054 adjusted_args_size.constant, struct_value_size,
3055 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3056 flags, & args_so_far);
3058 /* Verify that we've deallocated all the stack we used. */
3060 && old_stack_allocated != stack_pointer_delta - pending_stack_adjust)
3063 /* If call is cse'able, make appropriate pair of reg-notes around it.
3064 Test valreg so we don't crash; may safely ignore `const'
3065 if return type is void. Disable for PARALLEL return values, because
3066 we have no way to move such values into a pseudo register. */
3067 if (pass && (flags & ECF_LIBCALL_BLOCK))
3071 if (valreg == 0 || GET_CODE (valreg) == PARALLEL)
3073 insns = get_insns ();
3080 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3082 /* Mark the return value as a pointer if needed. */
3083 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3084 mark_reg_pointer (temp,
3085 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3087 /* Construct an "equal form" for the value which mentions all the
3088 arguments in order as well as the function name. */
3089 for (i = 0; i < num_actuals; i++)
3090 note = gen_rtx_EXPR_LIST (VOIDmode,
3091 args[i].initial_value, note);
3092 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3094 insns = get_insns ();
3097 if (flags & ECF_PURE)
3098 note = gen_rtx_EXPR_LIST (VOIDmode,
3099 gen_rtx_USE (VOIDmode,
3100 gen_rtx_MEM (BLKmode,
3101 gen_rtx_SCRATCH (VOIDmode))),
3104 emit_libcall_block (insns, temp, valreg, note);
3109 else if (pass && (flags & ECF_MALLOC))
3111 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3114 /* The return value from a malloc-like function is a pointer. */
3115 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3116 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3118 emit_move_insn (temp, valreg);
3120 /* The return value from a malloc-like function can not alias
3122 last = get_last_insn ();
3124 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3126 /* Write out the sequence. */
3127 insns = get_insns ();
3133 /* For calls to `setjmp', etc., inform flow.c it should complain
3134 if nonvolatile values are live. For functions that cannot return,
3135 inform flow that control does not fall through. */
3137 if ((flags & (ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3139 /* The barrier must be emitted
3140 immediately after the CALL_INSN. Some ports emit more
3141 than just a CALL_INSN above, so we must search for it here. */
3143 rtx last = get_last_insn ();
3144 while (GET_CODE (last) != CALL_INSN)
3146 last = PREV_INSN (last);
3147 /* There was no CALL_INSN? */
3148 if (last == before_call)
3152 emit_barrier_after (last);
3155 if (flags & ECF_LONGJMP)
3156 current_function_calls_longjmp = 1;
3158 /* If this function is returning into a memory location marked as
3159 readonly, it means it is initializing that location. But we normally
3160 treat functions as not clobbering such locations, so we need to
3161 specify that this one does. */
3162 if (target != 0 && GET_CODE (target) == MEM
3163 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
3164 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
3166 /* If value type not void, return an rtx for the value. */
3168 /* If there are cleanups to be called, don't use a hard reg as target.
3169 We need to double check this and see if it matters anymore. */
3170 if (any_pending_cleanups (1))
3172 if (target && REG_P (target)
3173 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3175 sibcall_failure = 1;
3178 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3180 target = const0_rtx;
3181 else if (structure_value_addr)
3183 if (target == 0 || GET_CODE (target) != MEM)
3186 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3187 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3188 structure_value_addr));
3189 set_mem_attributes (target, exp, 1);
3192 else if (pcc_struct_value)
3194 /* This is the special C++ case where we need to
3195 know what the true target was. We take care to
3196 never use this value more than once in one expression. */
3197 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3198 copy_to_reg (valreg));
3199 set_mem_attributes (target, exp, 1);
3201 /* Handle calls that return values in multiple non-contiguous locations.
3202 The Irix 6 ABI has examples of this. */
3203 else if (GET_CODE (valreg) == PARALLEL)
3207 /* This will only be assigned once, so it can be readonly. */
3208 tree nt = build_qualified_type (TREE_TYPE (exp),
3209 (TYPE_QUALS (TREE_TYPE (exp))
3210 | TYPE_QUAL_CONST));
3212 target = assign_temp (nt, 0, 1, 1);
3213 preserve_temp_slots (target);
3216 if (! rtx_equal_p (target, valreg))
3217 emit_group_store (target, valreg,
3218 int_size_in_bytes (TREE_TYPE (exp)));
3220 /* We can not support sibling calls for this case. */
3221 sibcall_failure = 1;
3224 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3225 && GET_MODE (target) == GET_MODE (valreg))
3227 /* TARGET and VALREG cannot be equal at this point because the
3228 latter would not have REG_FUNCTION_VALUE_P true, while the
3229 former would if it were referring to the same register.
3231 If they refer to the same register, this move will be a no-op,
3232 except when function inlining is being done. */
3233 emit_move_insn (target, valreg);
3235 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3237 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3239 /* We can not support sibling calls for this case. */
3240 sibcall_failure = 1;
3243 target = copy_to_reg (valreg);
3245 #ifdef PROMOTE_FUNCTION_RETURN
3246 /* If we promoted this return value, make the proper SUBREG. TARGET
3247 might be const0_rtx here, so be careful. */
3248 if (GET_CODE (target) == REG
3249 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3250 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3252 tree type = TREE_TYPE (exp);
3253 int unsignedp = TREE_UNSIGNED (type);
3256 /* If we don't promote as expected, something is wrong. */
3257 if (GET_MODE (target)
3258 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3261 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3262 && GET_MODE_SIZE (GET_MODE (target))
3263 > GET_MODE_SIZE (TYPE_MODE (type)))
3265 offset = GET_MODE_SIZE (GET_MODE (target))
3266 - GET_MODE_SIZE (TYPE_MODE (type));
3267 if (! BYTES_BIG_ENDIAN)
3268 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3269 else if (! WORDS_BIG_ENDIAN)
3270 offset %= UNITS_PER_WORD;
3272 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3273 SUBREG_PROMOTED_VAR_P (target) = 1;
3274 SUBREG_PROMOTED_UNSIGNED_SET (target, unsignedp);
3278 /* If size of args is variable or this was a constructor call for a stack
3279 argument, restore saved stack-pointer value. */
3281 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3283 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3284 pending_stack_adjust = old_pending_adj;
3285 stack_arg_under_construction = old_stack_arg_under_construction;
3286 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3287 stack_usage_map = initial_stack_usage_map;
3288 sibcall_failure = 1;
3290 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3292 #ifdef REG_PARM_STACK_SPACE
3295 restore_fixed_argument_area (save_area, argblock,
3296 high_to_save, low_to_save);
3300 /* If we saved any argument areas, restore them. */
3301 for (i = 0; i < num_actuals; i++)
3302 if (args[i].save_area)
3304 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3306 = gen_rtx_MEM (save_mode,
3307 memory_address (save_mode,
3308 XEXP (args[i].stack_slot, 0)));
3310 if (save_mode != BLKmode)
3311 emit_move_insn (stack_area, args[i].save_area);
3313 emit_block_move (stack_area,
3314 validize_mem (args[i].save_area),
3315 GEN_INT (args[i].size.constant));
3318 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3319 stack_usage_map = initial_stack_usage_map;
3322 /* If this was alloca, record the new stack level for nonlocal gotos.
3323 Check for the handler slots since we might not have a save area
3324 for non-local gotos. */
3326 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3327 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3329 /* Free up storage we no longer need. */
3330 for (i = 0; i < num_actuals; ++i)
3331 if (args[i].aligned_regs)
3332 free (args[i].aligned_regs);
3336 /* Undo the fake expand_start_target_temps we did earlier. If
3337 there had been any cleanups created, we've already set
3339 expand_end_target_temps ();
3342 insns = get_insns ();
3347 tail_call_insns = insns;
3349 /* Restore the pending stack adjustment now that we have
3350 finished generating the sibling call sequence. */
3352 pending_stack_adjust = save_pending_stack_adjust;
3353 stack_pointer_delta = save_stack_pointer_delta;
3355 /* Prepare arg structure for next iteration. */
3356 for (i = 0; i < num_actuals; i++)
3359 args[i].aligned_regs = 0;
3363 sbitmap_free (stored_args_map);
3366 normal_call_insns = insns;
3368 /* If something prevents making this a sibling call,
3369 zero out the sequence. */
3370 if (sibcall_failure)
3371 tail_call_insns = NULL_RTX;
3374 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3375 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3376 can happen if the arguments to this function call an inline
3377 function who's expansion contains another CALL_PLACEHOLDER.
3379 If there are any C_Ps in any of these sequences, replace them
3380 with their normal call. */
3382 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3383 if (GET_CODE (insn) == CALL_INSN
3384 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3385 replace_call_placeholder (insn, sibcall_use_normal);
3387 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3388 if (GET_CODE (insn) == CALL_INSN
3389 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3390 replace_call_placeholder (insn, sibcall_use_normal);
3392 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3393 if (GET_CODE (insn) == CALL_INSN
3394 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3395 replace_call_placeholder (insn, sibcall_use_normal);
3397 /* If this was a potential tail recursion site, then emit a
3398 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3399 One of them will be selected later. */
3400 if (tail_recursion_insns || tail_call_insns)
3402 /* The tail recursion label must be kept around. We could expose
3403 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3404 and makes determining true tail recursion sites difficult.
3406 So we set LABEL_PRESERVE_P here, then clear it when we select
3407 one of the call sequences after rtl generation is complete. */
3408 if (tail_recursion_insns)
3409 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3410 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3412 tail_recursion_insns,
3413 tail_recursion_label));
3416 emit_insns (normal_call_insns);
3418 currently_expanding_call--;
3420 /* If this function returns with the stack pointer depressed, ensure
3421 this block saves and restores the stack pointer, show it was
3422 changed, and adjust for any outgoing arg space. */
3423 if (flags & ECF_SP_DEPRESSED)
3425 clear_pending_stack_adjust ();
3426 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3427 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3428 save_stack_pointer ();
3434 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3435 The RETVAL parameter specifies whether return value needs to be saved, other
3436 parameters are documented in the emit_library_call function below. */
3439 emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3443 enum libcall_type fn_type;
3444 enum machine_mode outmode;
3448 /* Total size in bytes of all the stack-parms scanned so far. */
3449 struct args_size args_size;
3450 /* Size of arguments before any adjustments (such as rounding). */
3451 struct args_size original_args_size;
3456 struct args_size alignment_pad;
3458 CUMULATIVE_ARGS args_so_far;
3462 enum machine_mode mode;
3465 struct args_size offset;
3466 struct args_size size;
3470 int old_inhibit_defer_pop = inhibit_defer_pop;
3471 rtx call_fusage = 0;
3474 int pcc_struct_value = 0;
3475 int struct_value_size = 0;
3477 int reg_parm_stack_space = 0;
3480 tree tfom; /* type_for_mode (outmode, 0) */
3482 #ifdef REG_PARM_STACK_SPACE
3483 /* Define the boundary of the register parm stack space that needs to be
3485 int low_to_save = -1, high_to_save = 0;
3486 rtx save_area = 0; /* Place that it is saved. */
3489 /* Size of the stack reserved for parameter registers. */
3490 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3491 char *initial_stack_usage_map = stack_usage_map;
3493 #ifdef REG_PARM_STACK_SPACE
3494 #ifdef MAYBE_REG_PARM_STACK_SPACE
3495 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3497 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3501 /* By default, library functions can not throw. */
3502 flags = ECF_NOTHROW;
3514 case LCT_CONST_MAKE_BLOCK:
3515 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
3517 case LCT_PURE_MAKE_BLOCK:
3518 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
3521 flags |= ECF_NORETURN;
3524 flags = ECF_NORETURN;
3526 case LCT_ALWAYS_RETURN:
3527 flags = ECF_ALWAYS_RETURN;
3529 case LCT_RETURNS_TWICE:
3530 flags = ECF_RETURNS_TWICE;
3535 /* Ensure current function's preferred stack boundary is at least
3537 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3538 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3540 /* If this kind of value comes back in memory,
3541 decide where in memory it should come back. */
3542 if (outmode != VOIDmode)
3544 tfom = (*lang_hooks.types.type_for_mode) (outmode, 0);
3545 if (aggregate_value_p (tfom))
3547 #ifdef PCC_STATIC_STRUCT_RETURN
3549 = hard_function_value (build_pointer_type (tfom), 0, 0);
3550 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3551 pcc_struct_value = 1;
3553 value = gen_reg_rtx (outmode);
3554 #else /* not PCC_STATIC_STRUCT_RETURN */
3555 struct_value_size = GET_MODE_SIZE (outmode);
3556 if (value != 0 && GET_CODE (value) == MEM)
3559 mem_value = assign_temp (tfom, 0, 1, 1);
3561 /* This call returns a big structure. */
3562 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3566 tfom = void_type_node;
3568 /* ??? Unfinished: must pass the memory address as an argument. */
3570 /* Copy all the libcall-arguments out of the varargs data
3571 and into a vector ARGVEC.
3573 Compute how to pass each argument. We only support a very small subset
3574 of the full argument passing conventions to limit complexity here since
3575 library functions shouldn't have many args. */
3577 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3578 memset ((char *) argvec, 0, (nargs + 1) * sizeof (struct arg));
3580 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3581 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3583 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3586 args_size.constant = 0;
3591 /* Now we are about to start emitting insns that can be deleted
3592 if a libcall is deleted. */
3593 if (flags & ECF_LIBCALL_BLOCK)
3598 /* If there's a structure value address to be passed,
3599 either pass it in the special place, or pass it as an extra argument. */
3600 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3602 rtx addr = XEXP (mem_value, 0);
3605 /* Make sure it is a reasonable operand for a move or push insn. */
3606 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3607 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3608 addr = force_operand (addr, NULL_RTX);
3610 argvec[count].value = addr;
3611 argvec[count].mode = Pmode;
3612 argvec[count].partial = 0;
3614 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3615 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3616 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3620 locate_and_pad_parm (Pmode, NULL_TREE,
3621 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3624 argvec[count].reg != 0,
3626 NULL_TREE, &args_size, &argvec[count].offset,
3627 &argvec[count].size, &alignment_pad);
3629 if (argvec[count].reg == 0 || argvec[count].partial != 0
3630 || reg_parm_stack_space > 0)
3631 args_size.constant += argvec[count].size.constant;
3633 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3638 for (; count < nargs; count++)
3640 rtx val = va_arg (p, rtx);
3641 enum machine_mode mode = va_arg (p, enum machine_mode);
3643 /* We cannot convert the arg value to the mode the library wants here;
3644 must do it earlier where we know the signedness of the arg. */
3646 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3649 /* On some machines, there's no way to pass a float to a library fcn.
3650 Pass it as a double instead. */
3651 #ifdef LIBGCC_NEEDS_DOUBLE
3652 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3653 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3656 /* There's no need to call protect_from_queue, because
3657 either emit_move_insn or emit_push_insn will do that. */
3659 /* Make sure it is a reasonable operand for a move or push insn. */
3660 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3661 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3662 val = force_operand (val, NULL_RTX);
3664 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3665 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3669 #ifdef FUNCTION_ARG_CALLEE_COPIES
3670 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3675 if (GET_MODE (val) == MEM && ! must_copy)
3679 slot = assign_temp ((*lang_hooks.types.type_for_mode) (mode, 0),
3681 emit_move_insn (slot, val);
3685 tree type = (*lang_hooks.types.type_for_mode) (mode, 0);
3687 slot = gen_rtx_MEM (mode,
3688 expand_expr (build1 (ADDR_EXPR,
3691 make_tree (type, val)),
3692 NULL_RTX, VOIDmode, 0));
3695 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3696 gen_rtx_USE (VOIDmode, slot),
3699 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3700 gen_rtx_CLOBBER (VOIDmode,
3705 val = force_operand (XEXP (slot, 0), NULL_RTX);
3709 argvec[count].value = val;
3710 argvec[count].mode = mode;
3712 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3714 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3715 argvec[count].partial
3716 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3718 argvec[count].partial = 0;
3721 locate_and_pad_parm (mode, NULL_TREE,
3722 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3725 argvec[count].reg != 0,
3727 NULL_TREE, &args_size, &argvec[count].offset,
3728 &argvec[count].size, &alignment_pad);
3730 if (argvec[count].size.var)
3733 if (reg_parm_stack_space == 0 && argvec[count].partial)
3734 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3736 if (argvec[count].reg == 0 || argvec[count].partial != 0
3737 || reg_parm_stack_space > 0)
3738 args_size.constant += argvec[count].size.constant;
3740 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3743 #ifdef FINAL_REG_PARM_STACK_SPACE
3744 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3747 /* If this machine requires an external definition for library
3748 functions, write one out. */
3749 assemble_external_libcall (fun);
3751 original_args_size = args_size;
3752 args_size.constant = (((args_size.constant
3753 + stack_pointer_delta
3757 - stack_pointer_delta);
3759 args_size.constant = MAX (args_size.constant,
3760 reg_parm_stack_space);
3762 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3763 args_size.constant -= reg_parm_stack_space;
3766 if (args_size.constant > current_function_outgoing_args_size)
3767 current_function_outgoing_args_size = args_size.constant;
3769 if (ACCUMULATE_OUTGOING_ARGS)
3771 /* Since the stack pointer will never be pushed, it is possible for
3772 the evaluation of a parm to clobber something we have already
3773 written to the stack. Since most function calls on RISC machines
3774 do not use the stack, this is uncommon, but must work correctly.
3776 Therefore, we save any area of the stack that was already written
3777 and that we are using. Here we set up to do this by making a new
3778 stack usage map from the old one.
3780 Another approach might be to try to reorder the argument
3781 evaluations to avoid this conflicting stack usage. */
3783 needed = args_size.constant;
3785 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3786 /* Since we will be writing into the entire argument area, the
3787 map must be allocated for its entire size, not just the part that
3788 is the responsibility of the caller. */
3789 needed += reg_parm_stack_space;
3792 #ifdef ARGS_GROW_DOWNWARD
3793 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3796 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3799 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3801 if (initial_highest_arg_in_use)
3802 memcpy (stack_usage_map, initial_stack_usage_map,
3803 initial_highest_arg_in_use);
3805 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3806 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3807 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3810 /* We must be careful to use virtual regs before they're instantiated,
3811 and real regs afterwards. Loop optimization, for example, can create
3812 new libcalls after we've instantiated the virtual regs, and if we
3813 use virtuals anyway, they won't match the rtl patterns. */
3815 if (virtuals_instantiated)
3816 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
3818 argblock = virtual_outgoing_args_rtx;
3823 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3826 /* If we push args individually in reverse order, perform stack alignment
3827 before the first push (the last arg). */
3828 if (argblock == 0 && PUSH_ARGS_REVERSED)
3829 anti_adjust_stack (GEN_INT (args_size.constant
3830 - original_args_size.constant));
3832 if (PUSH_ARGS_REVERSED)
3843 #ifdef REG_PARM_STACK_SPACE
3844 if (ACCUMULATE_OUTGOING_ARGS)
3846 /* The argument list is the property of the called routine and it
3847 may clobber it. If the fixed area has been used for previous
3848 parameters, we must save and restore it.
3850 Here we compute the boundary of the that needs to be saved, if any. */
3852 #ifdef ARGS_GROW_DOWNWARD
3853 for (count = 0; count < reg_parm_stack_space + 1; count++)
3855 for (count = 0; count < reg_parm_stack_space; count++)
3858 if (count >= highest_outgoing_arg_in_use
3859 || stack_usage_map[count] == 0)
3862 if (low_to_save == -1)
3863 low_to_save = count;
3865 high_to_save = count;
3868 if (low_to_save >= 0)
3870 int num_to_save = high_to_save - low_to_save + 1;
3871 enum machine_mode save_mode
3872 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3875 /* If we don't have the required alignment, must do this in BLKmode. */
3876 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3877 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3878 save_mode = BLKmode;
3880 #ifdef ARGS_GROW_DOWNWARD
3881 stack_area = gen_rtx_MEM (save_mode,
3882 memory_address (save_mode,
3883 plus_constant (argblock,
3886 stack_area = gen_rtx_MEM (save_mode,
3887 memory_address (save_mode,
3888 plus_constant (argblock,
3891 if (save_mode == BLKmode)
3893 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3894 set_mem_align (save_area, PARM_BOUNDARY);
3895 emit_block_move (validize_mem (save_area), stack_area,
3896 GEN_INT (num_to_save));
3900 save_area = gen_reg_rtx (save_mode);
3901 emit_move_insn (save_area, stack_area);
3907 /* Push the args that need to be pushed. */
3909 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3910 are to be pushed. */
3911 for (count = 0; count < nargs; count++, argnum += inc)
3913 enum machine_mode mode = argvec[argnum].mode;
3914 rtx val = argvec[argnum].value;
3915 rtx reg = argvec[argnum].reg;
3916 int partial = argvec[argnum].partial;
3917 int lower_bound = 0, upper_bound = 0, i;
3919 if (! (reg != 0 && partial == 0))
3921 if (ACCUMULATE_OUTGOING_ARGS)
3923 /* If this is being stored into a pre-allocated, fixed-size,
3924 stack area, save any previous data at that location. */
3926 #ifdef ARGS_GROW_DOWNWARD
3927 /* stack_slot is negative, but we want to index stack_usage_map
3928 with positive values. */
3929 upper_bound = -argvec[argnum].offset.constant + 1;
3930 lower_bound = upper_bound - argvec[argnum].size.constant;
3932 lower_bound = argvec[argnum].offset.constant;
3933 upper_bound = lower_bound + argvec[argnum].size.constant;
3936 for (i = lower_bound; i < upper_bound; i++)
3937 if (stack_usage_map[i]
3938 /* Don't store things in the fixed argument area at this
3939 point; it has already been saved. */
3940 && i > reg_parm_stack_space)
3943 if (i != upper_bound)
3945 /* We need to make a save area. See what mode we can make
3947 enum machine_mode save_mode
3948 = mode_for_size (argvec[argnum].size.constant
3956 plus_constant (argblock,
3957 argvec[argnum].offset.constant)));
3958 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3960 emit_move_insn (argvec[argnum].save_area, stack_area);
3964 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
3965 argblock, GEN_INT (argvec[argnum].offset.constant),
3966 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3968 /* Now mark the segment we just used. */
3969 if (ACCUMULATE_OUTGOING_ARGS)
3970 for (i = lower_bound; i < upper_bound; i++)
3971 stack_usage_map[i] = 1;
3977 /* If we pushed args in forward order, perform stack alignment
3978 after pushing the last arg. */
3979 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3980 anti_adjust_stack (GEN_INT (args_size.constant
3981 - original_args_size.constant));
3983 if (PUSH_ARGS_REVERSED)
3988 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0, 0);
3990 /* Now load any reg parms into their regs. */
3992 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3993 are to be pushed. */
3994 for (count = 0; count < nargs; count++, argnum += inc)
3996 rtx val = argvec[argnum].value;
3997 rtx reg = argvec[argnum].reg;
3998 int partial = argvec[argnum].partial;
4000 /* Handle calls that pass values in multiple non-contiguous
4001 locations. The PA64 has examples of this for library calls. */
4002 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4003 emit_group_load (reg, val, GET_MODE_SIZE (GET_MODE (val)));
4004 else if (reg != 0 && partial == 0)
4005 emit_move_insn (reg, val);
4010 /* Any regs containing parms remain in use through the call. */
4011 for (count = 0; count < nargs; count++)
4013 rtx reg = argvec[count].reg;
4014 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4015 use_group_regs (&call_fusage, reg);
4017 use_reg (&call_fusage, reg);
4020 /* Pass the function the address in which to return a structure value. */
4021 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
4023 emit_move_insn (struct_value_rtx,
4025 force_operand (XEXP (mem_value, 0),
4027 if (GET_CODE (struct_value_rtx) == REG)
4028 use_reg (&call_fusage, struct_value_rtx);
4031 /* Don't allow popping to be deferred, since then
4032 cse'ing of library calls could delete a call and leave the pop. */
4034 valreg = (mem_value == 0 && outmode != VOIDmode
4035 ? hard_libcall_value (outmode) : NULL_RTX);
4037 /* Stack must be properly aligned now. */
4038 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4041 before_call = get_last_insn ();
4043 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4044 will set inhibit_defer_pop to that value. */
4045 /* The return type is needed to decide how many bytes the function pops.
4046 Signedness plays no role in that, so for simplicity, we pretend it's
4047 always signed. We also assume that the list of arguments passed has
4048 no impact, so we pretend it is unknown. */
4051 get_identifier (XSTR (orgfun, 0)),
4052 build_function_type (tfom, NULL_TREE),
4053 original_args_size.constant, args_size.constant,
4055 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4057 old_inhibit_defer_pop + 1, call_fusage, flags, & args_so_far);
4059 /* For calls to `setjmp', etc., inform flow.c it should complain
4060 if nonvolatile values are live. For functions that cannot return,
4061 inform flow that control does not fall through. */
4063 if (flags & (ECF_NORETURN | ECF_LONGJMP))
4065 /* The barrier note must be emitted
4066 immediately after the CALL_INSN. Some ports emit more than
4067 just a CALL_INSN above, so we must search for it here. */
4069 rtx last = get_last_insn ();
4070 while (GET_CODE (last) != CALL_INSN)
4072 last = PREV_INSN (last);
4073 /* There was no CALL_INSN? */
4074 if (last == before_call)
4078 emit_barrier_after (last);
4081 /* Now restore inhibit_defer_pop to its actual original value. */
4084 /* If call is cse'able, make appropriate pair of reg-notes around it.
4085 Test valreg so we don't crash; may safely ignore `const'
4086 if return type is void. Disable for PARALLEL return values, because
4087 we have no way to move such values into a pseudo register. */
4088 if (flags & ECF_LIBCALL_BLOCK)
4092 if (valreg == 0 || GET_CODE (valreg) == PARALLEL)
4094 insns = get_insns ();
4101 rtx temp = gen_reg_rtx (GET_MODE (valreg));
4104 /* Construct an "equal form" for the value which mentions all the
4105 arguments in order as well as the function name. */
4106 for (i = 0; i < nargs; i++)
4107 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4108 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4110 insns = get_insns ();
4113 if (flags & ECF_PURE)
4114 note = gen_rtx_EXPR_LIST (VOIDmode,
4115 gen_rtx_USE (VOIDmode,
4116 gen_rtx_MEM (BLKmode,
4117 gen_rtx_SCRATCH (VOIDmode))),
4120 emit_libcall_block (insns, temp, valreg, note);
4127 /* Copy the value to the right place. */
4128 if (outmode != VOIDmode && retval)
4134 if (value != mem_value)
4135 emit_move_insn (value, mem_value);
4137 else if (value != 0)
4138 emit_move_insn (value, hard_libcall_value (outmode));
4140 value = hard_libcall_value (outmode);
4143 if (ACCUMULATE_OUTGOING_ARGS)
4145 #ifdef REG_PARM_STACK_SPACE
4148 enum machine_mode save_mode = GET_MODE (save_area);
4149 #ifdef ARGS_GROW_DOWNWARD
4151 = gen_rtx_MEM (save_mode,
4152 memory_address (save_mode,
4153 plus_constant (argblock,
4157 = gen_rtx_MEM (save_mode,
4158 memory_address (save_mode,
4159 plus_constant (argblock, low_to_save)));
4162 set_mem_align (stack_area, PARM_BOUNDARY);
4163 if (save_mode != BLKmode)
4164 emit_move_insn (stack_area, save_area);
4166 emit_block_move (stack_area, validize_mem (save_area),
4167 GEN_INT (high_to_save - low_to_save + 1));
4171 /* If we saved any argument areas, restore them. */
4172 for (count = 0; count < nargs; count++)
4173 if (argvec[count].save_area)
4175 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4177 = gen_rtx_MEM (save_mode,
4180 plus_constant (argblock,
4181 argvec[count].offset.constant)));
4183 emit_move_insn (stack_area, argvec[count].save_area);
4186 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4187 stack_usage_map = initial_stack_usage_map;
4194 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4195 (emitting the queue unless NO_QUEUE is nonzero),
4196 for a value of mode OUTMODE,
4197 with NARGS different arguments, passed as alternating rtx values
4198 and machine_modes to convert them to.
4199 The rtx values should have been passed through protect_from_queue already.
4201 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4202 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4203 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4204 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4205 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4206 or other LCT_ value for other types of library calls. */
4209 emit_library_call VPARAMS((rtx orgfun, enum libcall_type fn_type,
4210 enum machine_mode outmode, int nargs, ...))
4213 VA_FIXEDARG (p, rtx, orgfun);
4214 VA_FIXEDARG (p, int, fn_type);
4215 VA_FIXEDARG (p, enum machine_mode, outmode);
4216 VA_FIXEDARG (p, int, nargs);
4218 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4223 /* Like emit_library_call except that an extra argument, VALUE,
4224 comes second and says where to store the result.
4225 (If VALUE is zero, this function chooses a convenient way
4226 to return the value.
4228 This function returns an rtx for where the value is to be found.
4229 If VALUE is nonzero, VALUE is returned. */
4232 emit_library_call_value VPARAMS((rtx orgfun, rtx value,
4233 enum libcall_type fn_type,
4234 enum machine_mode outmode, int nargs, ...))
4239 VA_FIXEDARG (p, rtx, orgfun);
4240 VA_FIXEDARG (p, rtx, value);
4241 VA_FIXEDARG (p, int, fn_type);
4242 VA_FIXEDARG (p, enum machine_mode, outmode);
4243 VA_FIXEDARG (p, int, nargs);
4245 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4253 /* Store a single argument for a function call
4254 into the register or memory area where it must be passed.
4255 *ARG describes the argument value and where to pass it.
4257 ARGBLOCK is the address of the stack-block for all the arguments,
4258 or 0 on a machine where arguments are pushed individually.
4260 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4261 so must be careful about how the stack is used.
4263 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4264 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4265 that we need not worry about saving and restoring the stack.
4267 FNDECL is the declaration of the function we are calling.
4269 Return non-zero if this arg should cause sibcall failure,
4273 store_one_arg (arg, argblock, flags, variable_size, reg_parm_stack_space)
4274 struct arg_data *arg;
4277 int variable_size ATTRIBUTE_UNUSED;
4278 int reg_parm_stack_space;
4280 tree pval = arg->tree_value;
4284 int i, lower_bound = 0, upper_bound = 0;
4285 int sibcall_failure = 0;
4287 if (TREE_CODE (pval) == ERROR_MARK)
4290 /* Push a new temporary level for any temporaries we make for
4294 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4296 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4297 save any previous data at that location. */
4298 if (argblock && ! variable_size && arg->stack)
4300 #ifdef ARGS_GROW_DOWNWARD
4301 /* stack_slot is negative, but we want to index stack_usage_map
4302 with positive values. */
4303 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4304 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4308 lower_bound = upper_bound - arg->size.constant;
4310 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4311 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4315 upper_bound = lower_bound + arg->size.constant;
4318 for (i = lower_bound; i < upper_bound; i++)
4319 if (stack_usage_map[i]
4320 /* Don't store things in the fixed argument area at this point;
4321 it has already been saved. */
4322 && i > reg_parm_stack_space)
4325 if (i != upper_bound)
4327 /* We need to make a save area. See what mode we can make it. */
4328 enum machine_mode save_mode
4329 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
4331 = gen_rtx_MEM (save_mode,
4332 memory_address (save_mode,
4333 XEXP (arg->stack_slot, 0)));
4335 if (save_mode == BLKmode)
4337 tree ot = TREE_TYPE (arg->tree_value);
4338 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4339 | TYPE_QUAL_CONST));
4341 arg->save_area = assign_temp (nt, 0, 1, 1);
4342 preserve_temp_slots (arg->save_area);
4343 emit_block_move (validize_mem (arg->save_area), stack_area,
4344 expr_size (arg->tree_value));
4348 arg->save_area = gen_reg_rtx (save_mode);
4349 emit_move_insn (arg->save_area, stack_area);
4353 /* Now that we have saved any slots that will be overwritten by this
4354 store, mark all slots this store will use. We must do this before
4355 we actually expand the argument since the expansion itself may
4356 trigger library calls which might need to use the same stack slot. */
4357 if (argblock && ! variable_size && arg->stack)
4358 for (i = lower_bound; i < upper_bound; i++)
4359 stack_usage_map[i] = 1;
4362 /* If this isn't going to be placed on both the stack and in registers,
4363 set up the register and number of words. */
4364 if (! arg->pass_on_stack)
4366 if (flags & ECF_SIBCALL)
4367 reg = arg->tail_call_reg;
4370 partial = arg->partial;
4373 if (reg != 0 && partial == 0)
4374 /* Being passed entirely in a register. We shouldn't be called in
4378 /* If this arg needs special alignment, don't load the registers
4380 if (arg->n_aligned_regs != 0)
4383 /* If this is being passed partially in a register, we can't evaluate
4384 it directly into its stack slot. Otherwise, we can. */
4385 if (arg->value == 0)
4387 /* stack_arg_under_construction is nonzero if a function argument is
4388 being evaluated directly into the outgoing argument list and
4389 expand_call must take special action to preserve the argument list
4390 if it is called recursively.
4392 For scalar function arguments stack_usage_map is sufficient to
4393 determine which stack slots must be saved and restored. Scalar
4394 arguments in general have pass_on_stack == 0.
4396 If this argument is initialized by a function which takes the
4397 address of the argument (a C++ constructor or a C function
4398 returning a BLKmode structure), then stack_usage_map is
4399 insufficient and expand_call must push the stack around the
4400 function call. Such arguments have pass_on_stack == 1.
4402 Note that it is always safe to set stack_arg_under_construction,
4403 but this generates suboptimal code if set when not needed. */
4405 if (arg->pass_on_stack)
4406 stack_arg_under_construction++;
4408 arg->value = expand_expr (pval,
4410 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4411 ? NULL_RTX : arg->stack,
4414 /* If we are promoting object (or for any other reason) the mode
4415 doesn't agree, convert the mode. */
4417 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4418 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4419 arg->value, arg->unsignedp);
4421 if (arg->pass_on_stack)
4422 stack_arg_under_construction--;
4425 /* Don't allow anything left on stack from computation
4426 of argument to alloca. */
4427 if (flags & ECF_MAY_BE_ALLOCA)
4428 do_pending_stack_adjust ();
4430 if (arg->value == arg->stack)
4431 /* If the value is already in the stack slot, we are done. */
4433 else if (arg->mode != BLKmode)
4437 /* Argument is a scalar, not entirely passed in registers.
4438 (If part is passed in registers, arg->partial says how much
4439 and emit_push_insn will take care of putting it there.)
4441 Push it, and if its size is less than the
4442 amount of space allocated to it,
4443 also bump stack pointer by the additional space.
4444 Note that in C the default argument promotions
4445 will prevent such mismatches. */
4447 size = GET_MODE_SIZE (arg->mode);
4448 /* Compute how much space the push instruction will push.
4449 On many machines, pushing a byte will advance the stack
4450 pointer by a halfword. */
4451 #ifdef PUSH_ROUNDING
4452 size = PUSH_ROUNDING (size);
4456 /* Compute how much space the argument should get:
4457 round up to a multiple of the alignment for arguments. */
4458 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4459 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4460 / (PARM_BOUNDARY / BITS_PER_UNIT))
4461 * (PARM_BOUNDARY / BITS_PER_UNIT));
4463 /* This isn't already where we want it on the stack, so put it there.
4464 This can either be done with push or copy insns. */
4465 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX, 0,
4466 partial, reg, used - size, argblock,
4467 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4468 ARGS_SIZE_RTX (arg->alignment_pad));
4470 /* Unless this is a partially-in-register argument, the argument is now
4473 arg->value = arg->stack;
4477 /* BLKmode, at least partly to be pushed. */
4482 /* Pushing a nonscalar.
4483 If part is passed in registers, PARTIAL says how much
4484 and emit_push_insn will take care of putting it there. */
4486 /* Round its size up to a multiple
4487 of the allocation unit for arguments. */
4489 if (arg->size.var != 0)
4492 size_rtx = ARGS_SIZE_RTX (arg->size);
4496 /* PUSH_ROUNDING has no effect on us, because
4497 emit_push_insn for BLKmode is careful to avoid it. */
4498 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4499 + partial * UNITS_PER_WORD);
4500 size_rtx = expr_size (pval);
4503 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4505 /* emit_push_insn might not work properly if arg->value and
4506 argblock + arg->offset areas overlap. */
4510 if (XEXP (x, 0) == current_function_internal_arg_pointer
4511 || (GET_CODE (XEXP (x, 0)) == PLUS
4512 && XEXP (XEXP (x, 0), 0) ==
4513 current_function_internal_arg_pointer
4514 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4516 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4517 i = INTVAL (XEXP (XEXP (x, 0), 1));
4519 /* expand_call should ensure this */
4520 if (arg->offset.var || GET_CODE (size_rtx) != CONST_INT)
4523 if (arg->offset.constant > i)
4525 if (arg->offset.constant < i + INTVAL (size_rtx))
4526 sibcall_failure = 1;
4528 else if (arg->offset.constant < i)
4530 if (i < arg->offset.constant + INTVAL (size_rtx))
4531 sibcall_failure = 1;
4536 /* Special handling is required if part of the parameter lies in the
4537 register parameter area. The argument may be copied into the stack
4538 slot using memcpy(), but the original contents of the register
4539 parameter area will be restored after the memcpy() call.
4541 To ensure that the part that lies in the register parameter area
4542 is copied correctly, we emit a separate push for that part. This
4543 push should be small enough to avoid a call to memcpy(). */
4544 #ifndef STACK_PARMS_IN_REG_PARM_AREA
4545 if (arg->reg && arg->pass_on_stack)
4550 if (arg->offset.constant < reg_parm_stack_space && arg->offset.var)
4551 error ("variable offset is passed partially in stack and in reg");
4552 else if (arg->offset.constant < reg_parm_stack_space && arg->size.var)
4553 error ("variable size is passed partially in stack and in reg");
4554 else if (arg->offset.constant < reg_parm_stack_space
4555 && ((arg->offset.constant + arg->size.constant)
4556 > reg_parm_stack_space))
4558 rtx size_rtx1 = GEN_INT (reg_parm_stack_space - arg->offset.constant);
4559 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx1,
4560 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg,
4561 excess, argblock, ARGS_SIZE_RTX (arg->offset),
4562 reg_parm_stack_space,
4563 ARGS_SIZE_RTX (arg->alignment_pad));
4568 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4569 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg, excess,
4570 argblock, ARGS_SIZE_RTX (arg->offset),
4571 reg_parm_stack_space,
4572 ARGS_SIZE_RTX (arg->alignment_pad));
4574 /* Unless this is a partially-in-register argument, the argument is now
4577 ??? Unlike the case above, in which we want the actual
4578 address of the data, so that we can load it directly into a
4579 register, here we want the address of the stack slot, so that
4580 it's properly aligned for word-by-word copying or something
4581 like that. It's not clear that this is always correct. */
4583 arg->value = arg->stack_slot;
4586 /* Once we have pushed something, pops can't safely
4587 be deferred during the rest of the arguments. */
4590 /* ANSI doesn't require a sequence point here,
4591 but PCC has one, so this will avoid some problems. */
4594 /* Free any temporary slots made in processing this argument. Show
4595 that we might have taken the address of something and pushed that
4597 preserve_temp_slots (NULL_RTX);
4601 return sibcall_failure;