1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998
3 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
24 #include "coretypes.h"
38 #include "langhooks.h"
43 /* Decide whether a function's arguments should be processed
44 from first to last or from last to first.
46 They should if the stack and args grow in opposite directions, but
47 only if we have push insns. */
51 #ifndef PUSH_ARGS_REVERSED
52 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
53 #define PUSH_ARGS_REVERSED PUSH_ARGS
59 #ifndef PUSH_ARGS_REVERSED
60 #define PUSH_ARGS_REVERSED 0
63 #ifndef STACK_POINTER_OFFSET
64 #define STACK_POINTER_OFFSET 0
67 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
68 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
70 /* Data structure and subroutines used within expand_call. */
74 /* Tree node for this argument. */
76 /* Mode for value; TYPE_MODE unless promoted. */
77 enum machine_mode mode;
78 /* Current RTL value for argument, or 0 if it isn't precomputed. */
80 /* Initially-compute RTL value for argument; only for const functions. */
82 /* Register to pass this argument in, 0 if passed on stack, or an
83 PARALLEL if the arg is to be copied into multiple non-contiguous
86 /* Register to pass this argument in when generating tail call sequence.
87 This is not the same register as for normal calls on machines with
90 /* If REG was promoted from the actual mode of the argument expression,
91 indicates whether the promotion is sign- or zero-extended. */
93 /* Number of registers to use. 0 means put the whole arg in registers.
94 Also 0 if not passed in registers. */
96 /* Nonzero if argument must be passed on stack.
97 Note that some arguments may be passed on the stack
98 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
99 pass_on_stack identifies arguments that *cannot* go in registers. */
101 /* Some fields packaged up for locate_and_pad_parm. */
102 struct locate_and_pad_arg_data locate;
103 /* Location on the stack at which parameter should be stored. The store
104 has already been done if STACK == VALUE. */
106 /* Location on the stack of the start of this argument slot. This can
107 differ from STACK if this arg pads downward. This location is known
108 to be aligned to FUNCTION_ARG_BOUNDARY. */
110 /* Place that this stack area has been saved, if needed. */
112 /* If an argument's alignment does not permit direct copying into registers,
113 copy in smaller-sized pieces into pseudos. These are stored in a
114 block pointed to by this field. The next field says how many
115 word-sized pseudos we made. */
120 /* A vector of one char per byte of stack space. A byte if nonzero if
121 the corresponding stack location has been used.
122 This vector is used to prevent a function call within an argument from
123 clobbering any stack already set up. */
124 static char *stack_usage_map;
126 /* Size of STACK_USAGE_MAP. */
127 static int highest_outgoing_arg_in_use;
129 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
130 stack location's tail call argument has been already stored into the stack.
131 This bitmap is used to prevent sibling call optimization if function tries
132 to use parent's incoming argument slots when they have been already
133 overwritten with tail call arguments. */
134 static sbitmap stored_args_map;
136 /* stack_arg_under_construction is nonzero when an argument may be
137 initialized with a constructor call (including a C function that
138 returns a BLKmode struct) and expand_call must take special action
139 to make sure the object being constructed does not overlap the
140 argument list for the constructor call. */
141 int stack_arg_under_construction;
143 static int calls_function PARAMS ((tree, int));
144 static int calls_function_1 PARAMS ((tree, int));
146 static void emit_call_1 PARAMS ((rtx, tree, tree, HOST_WIDE_INT,
147 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
150 static void precompute_register_parameters PARAMS ((int,
153 static int store_one_arg PARAMS ((struct arg_data *, rtx, int, int,
155 static void store_unaligned_arguments_into_pseudos PARAMS ((struct arg_data *,
157 static int finalize_must_preallocate PARAMS ((int, int,
159 struct args_size *));
160 static void precompute_arguments PARAMS ((int, int,
162 static int compute_argument_block_size PARAMS ((int,
165 static void initialize_argument_information PARAMS ((int,
172 static void compute_argument_addresses PARAMS ((struct arg_data *,
174 static rtx rtx_for_function_call PARAMS ((tree, tree));
175 static void load_register_parameters PARAMS ((struct arg_data *,
178 static rtx emit_library_call_value_1 PARAMS ((int, rtx, rtx,
182 static int special_function_p PARAMS ((tree, int));
183 static rtx try_to_integrate PARAMS ((tree, tree, rtx,
185 static int check_sibcall_argument_overlap_1 PARAMS ((rtx));
186 static int check_sibcall_argument_overlap PARAMS ((rtx, struct arg_data *,
189 static int combine_pending_stack_adjustment_and_call
190 PARAMS ((int, struct args_size *, int));
191 static tree fix_unsafe_tree PARAMS ((tree));
193 #ifdef REG_PARM_STACK_SPACE
194 static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
195 static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
198 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
201 If WHICH is 0, return 1 if EXP contains a call to any function.
202 Actually, we only need return 1 if evaluating EXP would require pushing
203 arguments on the stack, but that is too difficult to compute, so we just
204 assume any function call might require the stack. */
206 static tree calls_function_save_exprs;
209 calls_function (exp, which)
215 calls_function_save_exprs = 0;
216 val = calls_function_1 (exp, which);
217 calls_function_save_exprs = 0;
221 /* Recursive function to do the work of above function. */
224 calls_function_1 (exp, which)
229 enum tree_code code = TREE_CODE (exp);
230 int class = TREE_CODE_CLASS (code);
231 int length = first_rtl_op (code);
233 /* If this code is language-specific, we don't know what it will do. */
234 if ((int) code >= NUM_TREE_CODES)
242 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
244 && (TYPE_RETURNS_STACK_DEPRESSED
245 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))))
247 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
248 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
250 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
252 & ECF_MAY_BE_ALLOCA))
261 for (tem = CONSTRUCTOR_ELTS (exp); tem != 0; tem = TREE_CHAIN (tem))
262 if (calls_function_1 (TREE_VALUE (tem), which))
269 if (SAVE_EXPR_RTL (exp) != 0)
271 if (value_member (exp, calls_function_save_exprs))
273 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
274 calls_function_save_exprs);
275 return (TREE_OPERAND (exp, 0) != 0
276 && calls_function_1 (TREE_OPERAND (exp, 0), which));
283 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
284 if (DECL_INITIAL (local) != 0
285 && calls_function_1 (DECL_INITIAL (local), which))
288 for (subblock = BLOCK_SUBBLOCKS (exp);
290 subblock = TREE_CHAIN (subblock))
291 if (calls_function_1 (subblock, which))
297 for (; exp != 0; exp = TREE_CHAIN (exp))
298 if (calls_function_1 (TREE_VALUE (exp), which))
306 /* Only expressions, references, and blocks can contain calls. */
307 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
310 for (i = 0; i < length; i++)
311 if (TREE_OPERAND (exp, i) != 0
312 && calls_function_1 (TREE_OPERAND (exp, i), which))
318 /* Force FUNEXP into a form suitable for the address of a CALL,
319 and return that as an rtx. Also load the static chain register
320 if FNDECL is a nested function.
322 CALL_FUSAGE points to a variable holding the prospective
323 CALL_INSN_FUNCTION_USAGE information. */
326 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen, sibcallp)
333 rtx static_chain_value = 0;
335 funexp = protect_from_queue (funexp, 0);
338 /* Get possible static chain value for nested function in C. */
339 static_chain_value = lookup_static_chain (fndecl);
341 /* Make a valid memory address and copy constants thru pseudo-regs,
342 but not for a constant address if -fno-function-cse. */
343 if (GET_CODE (funexp) != SYMBOL_REF)
344 /* If we are using registers for parameters, force the
345 function address into a register now. */
346 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
347 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
348 : memory_address (FUNCTION_MODE, funexp));
351 #ifndef NO_FUNCTION_CSE
352 if (optimize && ! flag_no_function_cse)
353 #ifdef NO_RECURSIVE_FUNCTION_CSE
354 if (fndecl != current_function_decl)
356 funexp = force_reg (Pmode, funexp);
360 if (static_chain_value != 0)
362 emit_move_insn (static_chain_rtx, static_chain_value);
364 if (GET_CODE (static_chain_rtx) == REG)
365 use_reg (call_fusage, static_chain_rtx);
371 /* Generate instructions to call function FUNEXP,
372 and optionally pop the results.
373 The CALL_INSN is the first insn generated.
375 FNDECL is the declaration node of the function. This is given to the
376 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
378 FUNTYPE is the data type of the function. This is given to the macro
379 RETURN_POPS_ARGS to determine whether this function pops its own args.
380 We used to allow an identifier for library functions, but that doesn't
381 work when the return type is an aggregate type and the calling convention
382 says that the pointer to this aggregate is to be popped by the callee.
384 STACK_SIZE is the number of bytes of arguments on the stack,
385 ROUNDED_STACK_SIZE is that number rounded up to
386 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
387 both to put into the call insn and to generate explicit popping
390 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
391 It is zero if this call doesn't want a structure value.
393 NEXT_ARG_REG is the rtx that results from executing
394 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
395 just after all the args have had their registers assigned.
396 This could be whatever you like, but normally it is the first
397 arg-register beyond those used for args in this call,
398 or 0 if all the arg-registers are used in this call.
399 It is passed on to `gen_call' so you can put this info in the call insn.
401 VALREG is a hard register in which a value is returned,
402 or 0 if the call does not return a value.
404 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
405 the args to this call were processed.
406 We restore `inhibit_defer_pop' to that value.
408 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
409 denote registers used by the called function. */
412 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
413 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
414 call_fusage, ecf_flags, args_so_far)
416 tree fndecl ATTRIBUTE_UNUSED;
417 tree funtype ATTRIBUTE_UNUSED;
418 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
419 HOST_WIDE_INT rounded_stack_size;
420 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
421 rtx next_arg_reg ATTRIBUTE_UNUSED;
423 int old_inhibit_defer_pop;
426 CUMULATIVE_ARGS *args_so_far ATTRIBUTE_UNUSED;
428 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
430 int already_popped = 0;
431 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
432 #if defined (HAVE_call) && defined (HAVE_call_value)
433 rtx struct_value_size_rtx;
434 struct_value_size_rtx = GEN_INT (struct_value_size);
437 #ifdef CALL_POPS_ARGS
438 n_popped += CALL_POPS_ARGS (* args_so_far);
441 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
442 and we don't want to load it into a register as an optimization,
443 because prepare_call_address already did it if it should be done. */
444 if (GET_CODE (funexp) != SYMBOL_REF)
445 funexp = memory_address (FUNCTION_MODE, funexp);
447 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
448 if ((ecf_flags & ECF_SIBCALL)
449 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
450 && (n_popped > 0 || stack_size == 0))
452 rtx n_pop = GEN_INT (n_popped);
455 /* If this subroutine pops its own args, record that in the call insn
456 if possible, for the sake of frame pointer elimination. */
459 pat = GEN_SIBCALL_VALUE_POP (valreg,
460 gen_rtx_MEM (FUNCTION_MODE, funexp),
461 rounded_stack_size_rtx, next_arg_reg,
464 pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
465 rounded_stack_size_rtx, next_arg_reg, n_pop);
467 emit_call_insn (pat);
473 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
474 /* If the target has "call" or "call_value" insns, then prefer them
475 if no arguments are actually popped. If the target does not have
476 "call" or "call_value" insns, then we must use the popping versions
477 even if the call has no arguments to pop. */
478 #if defined (HAVE_call) && defined (HAVE_call_value)
479 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
480 && n_popped > 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
482 if (HAVE_call_pop && HAVE_call_value_pop)
485 rtx n_pop = GEN_INT (n_popped);
488 /* If this subroutine pops its own args, record that in the call insn
489 if possible, for the sake of frame pointer elimination. */
492 pat = GEN_CALL_VALUE_POP (valreg,
493 gen_rtx_MEM (FUNCTION_MODE, funexp),
494 rounded_stack_size_rtx, next_arg_reg, n_pop);
496 pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
497 rounded_stack_size_rtx, next_arg_reg, n_pop);
499 emit_call_insn (pat);
505 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
506 if ((ecf_flags & ECF_SIBCALL)
507 && HAVE_sibcall && HAVE_sibcall_value)
510 emit_call_insn (GEN_SIBCALL_VALUE (valreg,
511 gen_rtx_MEM (FUNCTION_MODE, funexp),
512 rounded_stack_size_rtx,
513 next_arg_reg, NULL_RTX));
515 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
516 rounded_stack_size_rtx, next_arg_reg,
517 struct_value_size_rtx));
522 #if defined (HAVE_call) && defined (HAVE_call_value)
523 if (HAVE_call && HAVE_call_value)
526 emit_call_insn (GEN_CALL_VALUE (valreg,
527 gen_rtx_MEM (FUNCTION_MODE, funexp),
528 rounded_stack_size_rtx, next_arg_reg,
531 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
532 rounded_stack_size_rtx, next_arg_reg,
533 struct_value_size_rtx));
539 /* Find the CALL insn we just emitted. */
540 for (call_insn = get_last_insn ();
541 call_insn && GET_CODE (call_insn) != CALL_INSN;
542 call_insn = PREV_INSN (call_insn))
548 /* Mark memory as used for "pure" function call. */
549 if (ecf_flags & ECF_PURE)
553 gen_rtx_USE (VOIDmode,
554 gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode))),
557 /* Put the register usage information on the CALL. If there is already
558 some usage information, put ours at the end. */
559 if (CALL_INSN_FUNCTION_USAGE (call_insn))
563 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
564 link = XEXP (link, 1))
567 XEXP (link, 1) = call_fusage;
570 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
572 /* If this is a const call, then set the insn's unchanging bit. */
573 if (ecf_flags & (ECF_CONST | ECF_PURE))
574 CONST_OR_PURE_CALL_P (call_insn) = 1;
576 /* If this call can't throw, attach a REG_EH_REGION reg note to that
578 if (ecf_flags & ECF_NOTHROW)
579 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
580 REG_NOTES (call_insn));
582 note_eh_region_may_contain_throw ();
584 if (ecf_flags & ECF_NORETURN)
585 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_NORETURN, const0_rtx,
586 REG_NOTES (call_insn));
587 if (ecf_flags & ECF_ALWAYS_RETURN)
588 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN, const0_rtx,
589 REG_NOTES (call_insn));
591 if (ecf_flags & ECF_RETURNS_TWICE)
593 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_SETJMP, const0_rtx,
594 REG_NOTES (call_insn));
595 current_function_calls_setjmp = 1;
598 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
600 /* Restore this now, so that we do defer pops for this call's args
601 if the context of the call as a whole permits. */
602 inhibit_defer_pop = old_inhibit_defer_pop;
607 CALL_INSN_FUNCTION_USAGE (call_insn)
608 = gen_rtx_EXPR_LIST (VOIDmode,
609 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
610 CALL_INSN_FUNCTION_USAGE (call_insn));
611 rounded_stack_size -= n_popped;
612 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
613 stack_pointer_delta -= n_popped;
616 if (!ACCUMULATE_OUTGOING_ARGS)
618 /* If returning from the subroutine does not automatically pop the args,
619 we need an instruction to pop them sooner or later.
620 Perhaps do it now; perhaps just record how much space to pop later.
622 If returning from the subroutine does pop the args, indicate that the
623 stack pointer will be changed. */
625 if (rounded_stack_size != 0)
627 if (ecf_flags & ECF_SP_DEPRESSED)
628 /* Just pretend we did the pop. */
629 stack_pointer_delta -= rounded_stack_size;
630 else if (flag_defer_pop && inhibit_defer_pop == 0
631 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
632 pending_stack_adjust += rounded_stack_size;
634 adjust_stack (rounded_stack_size_rtx);
637 /* When we accumulate outgoing args, we must avoid any stack manipulations.
638 Restore the stack pointer to its original value now. Usually
639 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
640 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
641 popping variants of functions exist as well.
643 ??? We may optimize similar to defer_pop above, but it is
644 probably not worthwhile.
646 ??? It will be worthwhile to enable combine_stack_adjustments even for
649 anti_adjust_stack (GEN_INT (n_popped));
652 /* Determine if the function identified by NAME and FNDECL is one with
653 special properties we wish to know about.
655 For example, if the function might return more than one time (setjmp), then
656 set RETURNS_TWICE to a nonzero value.
658 Similarly set LONGJMP for if the function is in the longjmp family.
660 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
661 space from the stack such as alloca. */
664 special_function_p (fndecl, flags)
668 if (! (flags & ECF_MALLOC)
669 && fndecl && DECL_NAME (fndecl)
670 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
671 /* Exclude functions not at the file scope, or not `extern',
672 since they are not the magic functions we would otherwise
674 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
676 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
677 const char *tname = name;
679 /* We assume that alloca will always be called by name. It
680 makes no sense to pass it as a pointer-to-function to
681 anything that does not understand its behavior. */
682 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
684 && ! strcmp (name, "alloca"))
685 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
687 && ! strcmp (name, "__builtin_alloca"))))
688 flags |= ECF_MAY_BE_ALLOCA;
690 /* Disregard prefix _, __ or __x. */
693 if (name[1] == '_' && name[2] == 'x')
695 else if (name[1] == '_')
704 && (! strcmp (tname, "setjmp")
705 || ! strcmp (tname, "setjmp_syscall")))
707 && ! strcmp (tname, "sigsetjmp"))
709 && ! strcmp (tname, "savectx")))
710 flags |= ECF_RETURNS_TWICE;
713 && ! strcmp (tname, "siglongjmp"))
714 flags |= ECF_LONGJMP;
716 else if ((tname[0] == 'q' && tname[1] == 's'
717 && ! strcmp (tname, "qsetjmp"))
718 || (tname[0] == 'v' && tname[1] == 'f'
719 && ! strcmp (tname, "vfork")))
720 flags |= ECF_RETURNS_TWICE;
722 else if (tname[0] == 'l' && tname[1] == 'o'
723 && ! strcmp (tname, "longjmp"))
724 flags |= ECF_LONGJMP;
726 else if ((tname[0] == 'f' && tname[1] == 'o'
727 && ! strcmp (tname, "fork"))
728 /* Linux specific: __clone. check NAME to insist on the
729 leading underscores, to avoid polluting the ISO / POSIX
731 || (name[0] == '_' && name[1] == '_'
732 && ! strcmp (tname, "clone"))
733 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
734 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
736 || ((tname[5] == 'p' || tname[5] == 'e')
737 && tname[6] == '\0'))))
738 flags |= ECF_FORK_OR_EXEC;
743 /* Return nonzero when tree represent call to longjmp. */
746 setjmp_call_p (fndecl)
749 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
752 /* Return true when exp contains alloca call. */
757 if (TREE_CODE (exp) == CALL_EXPR
758 && TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
759 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
761 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
762 0) & ECF_MAY_BE_ALLOCA))
767 /* Detect flags (function attributes) from the function decl or type node. */
770 flags_from_decl_or_type (exp)
778 struct cgraph_rtl_info *i = cgraph_rtl_info (exp);
779 type = TREE_TYPE (exp);
783 if (i->pure_function)
784 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
785 if (i->const_function)
786 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
789 /* The function exp may have the `malloc' attribute. */
790 if (DECL_IS_MALLOC (exp))
793 /* The function exp may have the `pure' attribute. */
794 if (DECL_IS_PURE (exp))
795 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
797 if (TREE_NOTHROW (exp))
798 flags |= ECF_NOTHROW;
801 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
802 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
804 if (TREE_THIS_VOLATILE (exp))
805 flags |= ECF_NORETURN;
807 /* Mark if the function returns with the stack pointer depressed. We
808 cannot consider it pure or constant in that case. */
809 if (TREE_CODE (type) == FUNCTION_TYPE && TYPE_RETURNS_STACK_DEPRESSED (type))
811 flags |= ECF_SP_DEPRESSED;
812 flags &= ~(ECF_PURE | ECF_CONST | ECF_LIBCALL_BLOCK);
818 /* Precompute all register parameters as described by ARGS, storing values
819 into fields within the ARGS array.
821 NUM_ACTUALS indicates the total number elements in the ARGS array.
823 Set REG_PARM_SEEN if we encounter a register parameter. */
826 precompute_register_parameters (num_actuals, args, reg_parm_seen)
828 struct arg_data *args;
835 for (i = 0; i < num_actuals; i++)
836 if (args[i].reg != 0 && ! args[i].pass_on_stack)
840 if (args[i].value == 0)
843 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
845 preserve_temp_slots (args[i].value);
848 /* ANSI doesn't require a sequence point here,
849 but PCC has one, so this will avoid some problems. */
853 /* If the value is a non-legitimate constant, force it into a
854 pseudo now. TLS symbols sometimes need a call to resolve. */
855 if (CONSTANT_P (args[i].value)
856 && !LEGITIMATE_CONSTANT_P (args[i].value))
857 args[i].value = force_reg (args[i].mode, args[i].value);
859 /* If we are to promote the function arg to a wider mode,
862 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
864 = convert_modes (args[i].mode,
865 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
866 args[i].value, args[i].unsignedp);
868 /* If the value is expensive, and we are inside an appropriately
869 short loop, put the value into a pseudo and then put the pseudo
872 For small register classes, also do this if this call uses
873 register parameters. This is to avoid reload conflicts while
874 loading the parameters registers. */
876 if ((! (GET_CODE (args[i].value) == REG
877 || (GET_CODE (args[i].value) == SUBREG
878 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
879 && args[i].mode != BLKmode
880 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
881 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
882 || preserve_subexpressions_p ()))
883 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
887 #ifdef REG_PARM_STACK_SPACE
889 /* The argument list is the property of the called routine and it
890 may clobber it. If the fixed area has been used for previous
891 parameters, we must save and restore it. */
894 save_fixed_argument_area (reg_parm_stack_space, argblock,
895 low_to_save, high_to_save)
896 int reg_parm_stack_space;
904 /* Compute the boundary of the area that needs to be saved, if any. */
905 high = reg_parm_stack_space;
906 #ifdef ARGS_GROW_DOWNWARD
909 if (high > highest_outgoing_arg_in_use)
910 high = highest_outgoing_arg_in_use;
912 for (low = 0; low < high; low++)
913 if (stack_usage_map[low] != 0)
916 enum machine_mode save_mode;
921 while (stack_usage_map[--high] == 0)
925 *high_to_save = high;
927 num_to_save = high - low + 1;
928 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
930 /* If we don't have the required alignment, must do this
932 if ((low & (MIN (GET_MODE_SIZE (save_mode),
933 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
936 #ifdef ARGS_GROW_DOWNWARD
941 stack_area = gen_rtx_MEM (save_mode,
942 memory_address (save_mode,
943 plus_constant (argblock,
946 set_mem_align (stack_area, PARM_BOUNDARY);
947 if (save_mode == BLKmode)
949 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
950 emit_block_move (validize_mem (save_area), stack_area,
951 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
955 save_area = gen_reg_rtx (save_mode);
956 emit_move_insn (save_area, stack_area);
966 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
972 enum machine_mode save_mode = GET_MODE (save_area);
976 #ifdef ARGS_GROW_DOWNWARD
977 delta = -high_to_save;
981 stack_area = gen_rtx_MEM (save_mode,
982 memory_address (save_mode,
983 plus_constant (argblock, delta)));
984 set_mem_align (stack_area, PARM_BOUNDARY);
986 if (save_mode != BLKmode)
987 emit_move_insn (stack_area, save_area);
989 emit_block_move (stack_area, validize_mem (save_area),
990 GEN_INT (high_to_save - low_to_save + 1),
993 #endif /* REG_PARM_STACK_SPACE */
995 /* If any elements in ARGS refer to parameters that are to be passed in
996 registers, but not in memory, and whose alignment does not permit a
997 direct copy into registers. Copy the values into a group of pseudos
998 which we will later copy into the appropriate hard registers.
1000 Pseudos for each unaligned argument will be stored into the array
1001 args[argnum].aligned_regs. The caller is responsible for deallocating
1002 the aligned_regs array if it is nonzero. */
1005 store_unaligned_arguments_into_pseudos (args, num_actuals)
1006 struct arg_data *args;
1011 for (i = 0; i < num_actuals; i++)
1012 if (args[i].reg != 0 && ! args[i].pass_on_stack
1013 && args[i].mode == BLKmode
1014 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1015 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1017 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1018 int big_endian_correction = 0;
1020 args[i].n_aligned_regs
1021 = args[i].partial ? args[i].partial
1022 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1024 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
1025 * args[i].n_aligned_regs);
1027 /* Structures smaller than a word are aligned to the least
1028 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1029 this means we must skip the empty high order bytes when
1030 calculating the bit offset. */
1031 if (BYTES_BIG_ENDIAN
1032 && bytes < UNITS_PER_WORD)
1033 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1035 for (j = 0; j < args[i].n_aligned_regs; j++)
1037 rtx reg = gen_reg_rtx (word_mode);
1038 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1039 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1041 args[i].aligned_regs[j] = reg;
1043 /* There is no need to restrict this code to loading items
1044 in TYPE_ALIGN sized hunks. The bitfield instructions can
1045 load up entire word sized registers efficiently.
1047 ??? This may not be needed anymore.
1048 We use to emit a clobber here but that doesn't let later
1049 passes optimize the instructions we emit. By storing 0 into
1050 the register later passes know the first AND to zero out the
1051 bitfield being set in the register is unnecessary. The store
1052 of 0 will be deleted as will at least the first AND. */
1054 emit_move_insn (reg, const0_rtx);
1056 bytes -= bitsize / BITS_PER_UNIT;
1057 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
1058 extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1059 word_mode, word_mode,
1066 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1069 NUM_ACTUALS is the total number of parameters.
1071 N_NAMED_ARGS is the total number of named arguments.
1073 FNDECL is the tree code for the target of this call (if known)
1075 ARGS_SO_FAR holds state needed by the target to know where to place
1078 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1079 for arguments which are passed in registers.
1081 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1082 and may be modified by this routine.
1084 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1085 flags which may may be modified by this routine. */
1088 initialize_argument_information (num_actuals, args, args_size, n_named_args,
1089 actparms, fndecl, args_so_far,
1090 reg_parm_stack_space, old_stack_level,
1091 old_pending_adj, must_preallocate,
1093 int num_actuals ATTRIBUTE_UNUSED;
1094 struct arg_data *args;
1095 struct args_size *args_size;
1096 int n_named_args ATTRIBUTE_UNUSED;
1099 CUMULATIVE_ARGS *args_so_far;
1100 int reg_parm_stack_space;
1101 rtx *old_stack_level;
1102 int *old_pending_adj;
1103 int *must_preallocate;
1106 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1109 /* Count arg position in order args appear. */
1115 args_size->constant = 0;
1118 /* In this loop, we consider args in the order they are written.
1119 We fill up ARGS from the front or from the back if necessary
1120 so that in any case the first arg to be pushed ends up at the front. */
1122 if (PUSH_ARGS_REVERSED)
1124 i = num_actuals - 1, inc = -1;
1125 /* In this case, must reverse order of args
1126 so that we compute and push the last arg first. */
1133 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1134 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1136 tree type = TREE_TYPE (TREE_VALUE (p));
1138 enum machine_mode mode;
1140 args[i].tree_value = TREE_VALUE (p);
1142 /* Replace erroneous argument with constant zero. */
1143 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1144 args[i].tree_value = integer_zero_node, type = integer_type_node;
1146 /* If TYPE is a transparent union, pass things the way we would
1147 pass the first field of the union. We have already verified that
1148 the modes are the same. */
1149 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1150 type = TREE_TYPE (TYPE_FIELDS (type));
1152 /* Decide where to pass this arg.
1154 args[i].reg is nonzero if all or part is passed in registers.
1156 args[i].partial is nonzero if part but not all is passed in registers,
1157 and the exact value says how many words are passed in registers.
1159 args[i].pass_on_stack is nonzero if the argument must at least be
1160 computed on the stack. It may then be loaded back into registers
1161 if args[i].reg is nonzero.
1163 These decisions are driven by the FUNCTION_... macros and must agree
1164 with those made by function.c. */
1166 /* See if this argument should be passed by invisible reference. */
1167 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1168 && contains_placeholder_p (TYPE_SIZE (type)))
1169 || TREE_ADDRESSABLE (type)
1170 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1171 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1172 type, argpos < n_named_args)
1176 /* If we're compiling a thunk, pass through invisible
1177 references instead of making a copy. */
1178 if (current_function_is_thunk
1179 #ifdef FUNCTION_ARG_CALLEE_COPIES
1180 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1181 type, argpos < n_named_args)
1182 /* If it's in a register, we must make a copy of it too. */
1183 /* ??? Is this a sufficient test? Is there a better one? */
1184 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1185 && REG_P (DECL_RTL (args[i].tree_value)))
1186 && ! TREE_ADDRESSABLE (type))
1190 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1191 new object from the argument. If we are passing by
1192 invisible reference, the callee will do that for us, so we
1193 can strip off the TARGET_EXPR. This is not always safe,
1194 but it is safe in the only case where this is a useful
1195 optimization; namely, when the argument is a plain object.
1196 In that case, the frontend is just asking the backend to
1197 make a bitwise copy of the argument. */
1199 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1200 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1201 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1202 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1204 args[i].tree_value = build1 (ADDR_EXPR,
1205 build_pointer_type (type),
1206 args[i].tree_value);
1207 type = build_pointer_type (type);
1209 else if (TREE_CODE (args[i].tree_value) == TARGET_EXPR)
1211 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1212 We implement this by passing the address of the temporary
1213 rather than expanding it into another allocated slot. */
1214 args[i].tree_value = build1 (ADDR_EXPR,
1215 build_pointer_type (type),
1216 args[i].tree_value);
1217 type = build_pointer_type (type);
1221 /* We make a copy of the object and pass the address to the
1222 function being called. */
1225 if (!COMPLETE_TYPE_P (type)
1226 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1227 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1228 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1229 STACK_CHECK_MAX_VAR_SIZE))))
1231 /* This is a variable-sized object. Make space on the stack
1233 rtx size_rtx = expr_size (TREE_VALUE (p));
1235 if (*old_stack_level == 0)
1237 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1238 *old_pending_adj = pending_stack_adjust;
1239 pending_stack_adjust = 0;
1242 copy = gen_rtx_MEM (BLKmode,
1243 allocate_dynamic_stack_space
1244 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1245 set_mem_attributes (copy, type, 1);
1248 copy = assign_temp (type, 0, 1, 0);
1250 store_expr (args[i].tree_value, copy, 0);
1251 *ecf_flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
1253 args[i].tree_value = build1 (ADDR_EXPR,
1254 build_pointer_type (type),
1255 make_tree (type, copy));
1256 type = build_pointer_type (type);
1260 mode = TYPE_MODE (type);
1261 unsignedp = TREE_UNSIGNED (type);
1263 #ifdef PROMOTE_FUNCTION_ARGS
1264 mode = promote_mode (type, mode, &unsignedp, 1);
1267 args[i].unsignedp = unsignedp;
1268 args[i].mode = mode;
1270 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1271 argpos < n_named_args);
1272 #ifdef FUNCTION_INCOMING_ARG
1273 /* If this is a sibling call and the machine has register windows, the
1274 register window has to be unwinded before calling the routine, so
1275 arguments have to go into the incoming registers. */
1276 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1277 argpos < n_named_args);
1279 args[i].tail_call_reg = args[i].reg;
1282 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1285 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1286 argpos < n_named_args);
1289 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1291 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1292 it means that we are to pass this arg in the register(s) designated
1293 by the PARALLEL, but also to pass it in the stack. */
1294 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1295 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1296 args[i].pass_on_stack = 1;
1298 /* If this is an addressable type, we must preallocate the stack
1299 since we must evaluate the object into its final location.
1301 If this is to be passed in both registers and the stack, it is simpler
1303 if (TREE_ADDRESSABLE (type)
1304 || (args[i].pass_on_stack && args[i].reg != 0))
1305 *must_preallocate = 1;
1307 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1308 we cannot consider this function call constant. */
1309 if (TREE_ADDRESSABLE (type))
1310 *ecf_flags &= ~ECF_LIBCALL_BLOCK;
1312 /* Compute the stack-size of this argument. */
1313 if (args[i].reg == 0 || args[i].partial != 0
1314 || reg_parm_stack_space > 0
1315 || args[i].pass_on_stack)
1316 locate_and_pad_parm (mode, type,
1317 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1322 args[i].pass_on_stack ? 0 : args[i].partial,
1323 fndecl, args_size, &args[i].locate);
1325 /* Update ARGS_SIZE, the total stack space for args so far. */
1327 args_size->constant += args[i].locate.size.constant;
1328 if (args[i].locate.size.var)
1329 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1331 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1332 have been used, etc. */
1334 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1335 argpos < n_named_args);
1339 /* Update ARGS_SIZE to contain the total size for the argument block.
1340 Return the original constant component of the argument block's size.
1342 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1343 for arguments passed in registers. */
1346 compute_argument_block_size (reg_parm_stack_space, args_size,
1347 preferred_stack_boundary)
1348 int reg_parm_stack_space;
1349 struct args_size *args_size;
1350 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1352 int unadjusted_args_size = args_size->constant;
1354 /* For accumulate outgoing args mode we don't need to align, since the frame
1355 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1356 backends from generating misaligned frame sizes. */
1357 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1358 preferred_stack_boundary = STACK_BOUNDARY;
1360 /* Compute the actual size of the argument block required. The variable
1361 and constant sizes must be combined, the size may have to be rounded,
1362 and there may be a minimum required size. */
1366 args_size->var = ARGS_SIZE_TREE (*args_size);
1367 args_size->constant = 0;
1369 preferred_stack_boundary /= BITS_PER_UNIT;
1370 if (preferred_stack_boundary > 1)
1372 /* We don't handle this case yet. To handle it correctly we have
1373 to add the delta, round and subtract the delta.
1374 Currently no machine description requires this support. */
1375 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1377 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1380 if (reg_parm_stack_space > 0)
1383 = size_binop (MAX_EXPR, args_size->var,
1384 ssize_int (reg_parm_stack_space));
1386 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1387 /* The area corresponding to register parameters is not to count in
1388 the size of the block we need. So make the adjustment. */
1390 = size_binop (MINUS_EXPR, args_size->var,
1391 ssize_int (reg_parm_stack_space));
1397 preferred_stack_boundary /= BITS_PER_UNIT;
1398 if (preferred_stack_boundary < 1)
1399 preferred_stack_boundary = 1;
1400 args_size->constant = (((args_size->constant
1401 + stack_pointer_delta
1402 + preferred_stack_boundary - 1)
1403 / preferred_stack_boundary
1404 * preferred_stack_boundary)
1405 - stack_pointer_delta);
1407 args_size->constant = MAX (args_size->constant,
1408 reg_parm_stack_space);
1410 #ifdef MAYBE_REG_PARM_STACK_SPACE
1411 if (reg_parm_stack_space == 0)
1412 args_size->constant = 0;
1415 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1416 args_size->constant -= reg_parm_stack_space;
1419 return unadjusted_args_size;
1422 /* Precompute parameters as needed for a function call.
1424 FLAGS is mask of ECF_* constants.
1426 NUM_ACTUALS is the number of arguments.
1428 ARGS is an array containing information for each argument; this
1429 routine fills in the INITIAL_VALUE and VALUE fields for each
1430 precomputed argument. */
1433 precompute_arguments (flags, num_actuals, args)
1436 struct arg_data *args;
1440 /* If this function call is cse'able, precompute all the parameters.
1441 Note that if the parameter is constructed into a temporary, this will
1442 cause an additional copy because the parameter will be constructed
1443 into a temporary location and then copied into the outgoing arguments.
1444 If a parameter contains a call to alloca and this function uses the
1445 stack, precompute the parameter. */
1447 /* If we preallocated the stack space, and some arguments must be passed
1448 on the stack, then we must precompute any parameter which contains a
1449 function call which will store arguments on the stack.
1450 Otherwise, evaluating the parameter may clobber previous parameters
1451 which have already been stored into the stack. (we have code to avoid
1452 such case by saving the outgoing stack arguments, but it results in
1455 for (i = 0; i < num_actuals; i++)
1456 if ((flags & ECF_LIBCALL_BLOCK)
1457 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1459 enum machine_mode mode;
1461 /* If this is an addressable type, we cannot pre-evaluate it. */
1462 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1466 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1468 /* ANSI doesn't require a sequence point here,
1469 but PCC has one, so this will avoid some problems. */
1472 args[i].initial_value = args[i].value
1473 = protect_from_queue (args[i].value, 0);
1475 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1476 if (mode != args[i].mode)
1479 = convert_modes (args[i].mode, mode,
1480 args[i].value, args[i].unsignedp);
1481 #ifdef PROMOTE_FOR_CALL_ONLY
1482 /* CSE will replace this only if it contains args[i].value
1483 pseudo, so convert it down to the declared mode using
1485 if (GET_CODE (args[i].value) == REG
1486 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1488 args[i].initial_value
1489 = gen_lowpart_SUBREG (mode, args[i].value);
1490 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1491 SUBREG_PROMOTED_UNSIGNED_SET (args[i].initial_value,
1499 /* Given the current state of MUST_PREALLOCATE and information about
1500 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1501 compute and return the final value for MUST_PREALLOCATE. */
1504 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1505 int must_preallocate;
1507 struct arg_data *args;
1508 struct args_size *args_size;
1510 /* See if we have or want to preallocate stack space.
1512 If we would have to push a partially-in-regs parm
1513 before other stack parms, preallocate stack space instead.
1515 If the size of some parm is not a multiple of the required stack
1516 alignment, we must preallocate.
1518 If the total size of arguments that would otherwise create a copy in
1519 a temporary (such as a CALL) is more than half the total argument list
1520 size, preallocation is faster.
1522 Another reason to preallocate is if we have a machine (like the m88k)
1523 where stack alignment is required to be maintained between every
1524 pair of insns, not just when the call is made. However, we assume here
1525 that such machines either do not have push insns (and hence preallocation
1526 would occur anyway) or the problem is taken care of with
1529 if (! must_preallocate)
1531 int partial_seen = 0;
1532 int copy_to_evaluate_size = 0;
1535 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1537 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1539 else if (partial_seen && args[i].reg == 0)
1540 must_preallocate = 1;
1542 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1543 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1544 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1545 || TREE_CODE (args[i].tree_value) == COND_EXPR
1546 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1547 copy_to_evaluate_size
1548 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1551 if (copy_to_evaluate_size * 2 >= args_size->constant
1552 && args_size->constant > 0)
1553 must_preallocate = 1;
1555 return must_preallocate;
1558 /* If we preallocated stack space, compute the address of each argument
1559 and store it into the ARGS array.
1561 We need not ensure it is a valid memory address here; it will be
1562 validized when it is used.
1564 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1567 compute_argument_addresses (args, argblock, num_actuals)
1568 struct arg_data *args;
1574 rtx arg_reg = argblock;
1575 int i, arg_offset = 0;
1577 if (GET_CODE (argblock) == PLUS)
1578 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1580 for (i = 0; i < num_actuals; i++)
1582 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
1583 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
1586 /* Skip this parm if it will not be passed on the stack. */
1587 if (! args[i].pass_on_stack && args[i].reg != 0)
1590 if (GET_CODE (offset) == CONST_INT)
1591 addr = plus_constant (arg_reg, INTVAL (offset));
1593 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1595 addr = plus_constant (addr, arg_offset);
1596 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1597 set_mem_align (args[i].stack, PARM_BOUNDARY);
1598 set_mem_attributes (args[i].stack,
1599 TREE_TYPE (args[i].tree_value), 1);
1601 if (GET_CODE (slot_offset) == CONST_INT)
1602 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1604 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1606 addr = plus_constant (addr, arg_offset);
1607 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1608 set_mem_align (args[i].stack_slot, PARM_BOUNDARY);
1609 set_mem_attributes (args[i].stack_slot,
1610 TREE_TYPE (args[i].tree_value), 1);
1612 /* Function incoming arguments may overlap with sibling call
1613 outgoing arguments and we cannot allow reordering of reads
1614 from function arguments with stores to outgoing arguments
1615 of sibling calls. */
1616 set_mem_alias_set (args[i].stack, 0);
1617 set_mem_alias_set (args[i].stack_slot, 0);
1622 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1623 in a call instruction.
1625 FNDECL is the tree node for the target function. For an indirect call
1626 FNDECL will be NULL_TREE.
1628 ADDR is the operand 0 of CALL_EXPR for this call. */
1631 rtx_for_function_call (fndecl, addr)
1637 /* Get the function to call, in the form of RTL. */
1640 /* If this is the first use of the function, see if we need to
1641 make an external definition for it. */
1642 if (! TREE_USED (fndecl))
1644 assemble_external (fndecl);
1645 TREE_USED (fndecl) = 1;
1648 /* Get a SYMBOL_REF rtx for the function address. */
1649 funexp = XEXP (DECL_RTL (fndecl), 0);
1652 /* Generate an rtx (probably a pseudo-register) for the address. */
1655 funexp = expand_expr (addr, NULL_RTX, VOIDmode, 0);
1656 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1662 /* Do the register loads required for any wholly-register parms or any
1663 parms which are passed both on the stack and in a register. Their
1664 expressions were already evaluated.
1666 Mark all register-parms as living through the call, putting these USE
1667 insns in the CALL_INSN_FUNCTION_USAGE field.
1669 When IS_SIBCALL, perform the check_sibcall_overlap_argument_overlap
1670 checking, setting *SIBCALL_FAILURE if appropriate. */
1673 load_register_parameters (args, num_actuals, call_fusage, flags,
1674 is_sibcall, sibcall_failure)
1675 struct arg_data *args;
1680 int *sibcall_failure;
1684 #ifdef LOAD_ARGS_REVERSED
1685 for (i = num_actuals - 1; i >= 0; i--)
1687 for (i = 0; i < num_actuals; i++)
1690 rtx reg = ((flags & ECF_SIBCALL)
1691 ? args[i].tail_call_reg : args[i].reg);
1692 int partial = args[i].partial;
1697 rtx before_arg = get_last_insn ();
1698 /* Set to non-negative if must move a word at a time, even if just
1699 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1700 we just use a normal move insn. This value can be zero if the
1701 argument is a zero size structure with no fields. */
1702 nregs = (partial ? partial
1703 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1704 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1705 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1708 /* Handle calls that pass values in multiple non-contiguous
1709 locations. The Irix 6 ABI has examples of this. */
1711 if (GET_CODE (reg) == PARALLEL)
1712 emit_group_load (reg, args[i].value,
1713 int_size_in_bytes (TREE_TYPE (args[i].tree_value)));
1715 /* If simple case, just do move. If normal partial, store_one_arg
1716 has already loaded the register for us. In all other cases,
1717 load the register(s) from memory. */
1719 else if (nregs == -1)
1720 emit_move_insn (reg, args[i].value);
1722 /* If we have pre-computed the values to put in the registers in
1723 the case of non-aligned structures, copy them in now. */
1725 else if (args[i].n_aligned_regs != 0)
1726 for (j = 0; j < args[i].n_aligned_regs; j++)
1727 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1728 args[i].aligned_regs[j]);
1730 else if (partial == 0 || args[i].pass_on_stack)
1731 move_block_to_reg (REGNO (reg),
1732 validize_mem (args[i].value), nregs,
1735 /* When a parameter is a block, and perhaps in other cases, it is
1736 possible that it did a load from an argument slot that was
1737 already clobbered. */
1739 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
1740 *sibcall_failure = 1;
1742 /* Handle calls that pass values in multiple non-contiguous
1743 locations. The Irix 6 ABI has examples of this. */
1744 if (GET_CODE (reg) == PARALLEL)
1745 use_group_regs (call_fusage, reg);
1746 else if (nregs == -1)
1747 use_reg (call_fusage, reg);
1749 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1754 /* Try to integrate function. See expand_inline_function for documentation
1755 about the parameters. */
1758 try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1764 rtx structure_value_addr;
1769 rtx old_stack_level = 0;
1770 int reg_parm_stack_space = 0;
1772 #ifdef REG_PARM_STACK_SPACE
1773 #ifdef MAYBE_REG_PARM_STACK_SPACE
1774 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1776 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1780 before_call = get_last_insn ();
1782 timevar_push (TV_INTEGRATION);
1784 temp = expand_inline_function (fndecl, actparms, target,
1786 structure_value_addr);
1788 timevar_pop (TV_INTEGRATION);
1790 /* If inlining succeeded, return. */
1791 if (temp != (rtx) (size_t) - 1)
1793 if (ACCUMULATE_OUTGOING_ARGS)
1795 /* If the outgoing argument list must be preserved, push
1796 the stack before executing the inlined function if it
1799 i = reg_parm_stack_space;
1800 if (i > highest_outgoing_arg_in_use)
1801 i = highest_outgoing_arg_in_use;
1802 while (--i >= 0 && stack_usage_map[i] == 0)
1805 if (stack_arg_under_construction || i >= 0)
1808 = before_call ? NEXT_INSN (before_call) : get_insns ();
1809 rtx insn = NULL_RTX, seq;
1811 /* Look for a call in the inline function code.
1812 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1813 nonzero then there is a call and it is not necessary
1814 to scan the insns. */
1816 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1817 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1818 if (GET_CODE (insn) == CALL_INSN)
1823 /* Reserve enough stack space so that the largest
1824 argument list of any function call in the inline
1825 function does not overlap the argument list being
1826 evaluated. This is usually an overestimate because
1827 allocate_dynamic_stack_space reserves space for an
1828 outgoing argument list in addition to the requested
1829 space, but there is no way to ask for stack space such
1830 that an argument list of a certain length can be
1833 Add the stack space reserved for register arguments, if
1834 any, in the inline function. What is really needed is the
1835 largest value of reg_parm_stack_space in the inline
1836 function, but that is not available. Using the current
1837 value of reg_parm_stack_space is wrong, but gives
1838 correct results on all supported machines. */
1840 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1841 + reg_parm_stack_space);
1844 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1845 allocate_dynamic_stack_space (GEN_INT (adjust),
1846 NULL_RTX, BITS_PER_UNIT);
1849 emit_insn_before (seq, first_insn);
1850 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1855 /* If the result is equivalent to TARGET, return TARGET to simplify
1856 checks in store_expr. They can be equivalent but not equal in the
1857 case of a function that returns BLKmode. */
1858 if (temp != target && rtx_equal_p (temp, target))
1863 /* If inlining failed, mark FNDECL as needing to be compiled
1864 separately after all. If function was declared inline,
1866 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1867 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1869 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1870 warning ("called from here");
1872 (*lang_hooks.mark_addressable) (fndecl);
1873 return (rtx) (size_t) - 1;
1876 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1877 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1878 bytes, then we would need to push some additional bytes to pad the
1879 arguments. So, we compute an adjust to the stack pointer for an
1880 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1881 bytes. Then, when the arguments are pushed the stack will be perfectly
1882 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1883 be popped after the call. Returns the adjustment. */
1886 combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1888 preferred_unit_stack_boundary)
1889 int unadjusted_args_size;
1890 struct args_size *args_size;
1891 int preferred_unit_stack_boundary;
1893 /* The number of bytes to pop so that the stack will be
1894 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1895 HOST_WIDE_INT adjustment;
1896 /* The alignment of the stack after the arguments are pushed, if we
1897 just pushed the arguments without adjust the stack here. */
1898 HOST_WIDE_INT unadjusted_alignment;
1900 unadjusted_alignment
1901 = ((stack_pointer_delta + unadjusted_args_size)
1902 % preferred_unit_stack_boundary);
1904 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1905 as possible -- leaving just enough left to cancel out the
1906 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1907 PENDING_STACK_ADJUST is non-negative, and congruent to
1908 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1910 /* Begin by trying to pop all the bytes. */
1911 unadjusted_alignment
1912 = (unadjusted_alignment
1913 - (pending_stack_adjust % preferred_unit_stack_boundary));
1914 adjustment = pending_stack_adjust;
1915 /* Push enough additional bytes that the stack will be aligned
1916 after the arguments are pushed. */
1917 if (preferred_unit_stack_boundary > 1)
1919 if (unadjusted_alignment > 0)
1920 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1922 adjustment += unadjusted_alignment;
1925 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1926 bytes after the call. The right number is the entire
1927 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1928 by the arguments in the first place. */
1930 = pending_stack_adjust - adjustment + unadjusted_args_size;
1935 /* Scan X expression if it does not dereference any argument slots
1936 we already clobbered by tail call arguments (as noted in stored_args_map
1938 Return nonzero if X expression dereferences such argument slots,
1942 check_sibcall_argument_overlap_1 (x)
1953 code = GET_CODE (x);
1957 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1959 else if (GET_CODE (XEXP (x, 0)) == PLUS
1960 && XEXP (XEXP (x, 0), 0) ==
1961 current_function_internal_arg_pointer
1962 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1963 i = INTVAL (XEXP (XEXP (x, 0), 1));
1967 #ifdef ARGS_GROW_DOWNWARD
1968 i = -i - GET_MODE_SIZE (GET_MODE (x));
1971 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
1972 if (i + k < stored_args_map->n_bits
1973 && TEST_BIT (stored_args_map, i + k))
1979 /* Scan all subexpressions. */
1980 fmt = GET_RTX_FORMAT (code);
1981 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1985 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
1988 else if (*fmt == 'E')
1990 for (j = 0; j < XVECLEN (x, i); j++)
1991 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
1998 /* Scan sequence after INSN if it does not dereference any argument slots
1999 we already clobbered by tail call arguments (as noted in stored_args_map
2000 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2001 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2002 should be 0). Return nonzero if sequence after INSN dereferences such argument
2003 slots, zero otherwise. */
2006 check_sibcall_argument_overlap (insn, arg, mark_stored_args_map)
2008 struct arg_data *arg;
2009 int mark_stored_args_map;
2013 if (insn == NULL_RTX)
2014 insn = get_insns ();
2016 insn = NEXT_INSN (insn);
2018 for (; insn; insn = NEXT_INSN (insn))
2020 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2023 if (mark_stored_args_map)
2025 #ifdef ARGS_GROW_DOWNWARD
2026 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
2028 low = arg->locate.slot_offset.constant;
2031 for (high = low + arg->locate.size.constant; low < high; low++)
2032 SET_BIT (stored_args_map, low);
2034 return insn != NULL_RTX;
2041 switch (unsafe_for_reeval (t))
2046 case 1: /* Mildly unsafe. */
2047 t = unsave_expr (t);
2050 case 2: /* Wildly unsafe. */
2052 tree var = build_decl (VAR_DECL, NULL_TREE,
2055 expand_expr (t, NULL_RTX, VOIDmode, EXPAND_NORMAL));
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, 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;
2170 int old_stack_allocated;
2172 /* State variables to track stack modifications. */
2173 rtx old_stack_level = 0;
2174 int old_stack_arg_under_construction = 0;
2175 int old_pending_adj = 0;
2176 int old_inhibit_defer_pop = inhibit_defer_pop;
2178 /* Some stack pointer alterations we make are performed via
2179 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2180 which we then also need to save/restore along the way. */
2181 int old_stack_pointer_delta = 0;
2184 tree p = TREE_OPERAND (exp, 0);
2185 tree addr = TREE_OPERAND (exp, 0);
2187 /* The alignment of the stack, in bits. */
2188 HOST_WIDE_INT preferred_stack_boundary;
2189 /* The alignment of the stack, in bytes. */
2190 HOST_WIDE_INT preferred_unit_stack_boundary;
2192 /* See if this is "nothrow" function call. */
2193 if (TREE_NOTHROW (exp))
2194 flags |= ECF_NOTHROW;
2196 /* See if we can find a DECL-node for the actual function.
2197 As a result, decide whether this is a call to an integrable function. */
2199 fndecl = get_callee_fndecl (exp);
2203 && fndecl != current_function_decl
2204 && DECL_INLINE (fndecl)
2205 && DECL_SAVED_INSNS (fndecl)
2206 && DECL_SAVED_INSNS (fndecl)->inlinable)
2208 else if (! TREE_ADDRESSABLE (fndecl))
2210 /* In case this function later becomes inlinable,
2211 record that there was already a non-inline call to it.
2213 Use abstraction instead of setting TREE_ADDRESSABLE
2215 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2218 warning_with_decl (fndecl, "can't inline call to `%s'");
2219 warning ("called from here");
2221 (*lang_hooks.mark_addressable) (fndecl);
2224 flags |= flags_from_decl_or_type (fndecl);
2227 /* If we don't have specific function to call, see if we have a
2228 attributes set in the type. */
2230 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2232 #ifdef REG_PARM_STACK_SPACE
2233 #ifdef MAYBE_REG_PARM_STACK_SPACE
2234 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2236 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2240 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2241 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2242 must_preallocate = 1;
2245 /* Warn if this value is an aggregate type,
2246 regardless of which calling convention we are using for it. */
2247 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2248 warning ("function call has aggregate value");
2250 /* Set up a place to return a structure. */
2252 /* Cater to broken compilers. */
2253 if (aggregate_value_p (exp))
2255 /* This call returns a big structure. */
2256 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
2258 #ifdef PCC_STATIC_STRUCT_RETURN
2260 pcc_struct_value = 1;
2261 /* Easier than making that case work right. */
2264 /* In case this is a static function, note that it has been
2266 if (! TREE_ADDRESSABLE (fndecl))
2267 (*lang_hooks.mark_addressable) (fndecl);
2271 #else /* not PCC_STATIC_STRUCT_RETURN */
2273 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2275 if (CALL_EXPR_HAS_RETURN_SLOT_ADDR (exp))
2277 /* The structure value address arg is already in actparms.
2278 Pull it out. It might be nice to just leave it there, but
2279 we need to set structure_value_addr. */
2280 tree return_arg = TREE_VALUE (actparms);
2281 actparms = TREE_CHAIN (actparms);
2282 structure_value_addr = expand_expr (return_arg, NULL_RTX,
2283 VOIDmode, EXPAND_NORMAL);
2285 else if (target && GET_CODE (target) == MEM)
2286 structure_value_addr = XEXP (target, 0);
2289 /* For variable-sized objects, we must be called with a target
2290 specified. If we were to allocate space on the stack here,
2291 we would have no way of knowing when to free it. */
2292 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2294 mark_temp_addr_taken (d);
2295 structure_value_addr = XEXP (d, 0);
2299 #endif /* not PCC_STATIC_STRUCT_RETURN */
2302 /* If called function is inline, try to integrate it. */
2306 rtx temp = try_to_integrate (fndecl, actparms, target,
2307 ignore, TREE_TYPE (exp),
2308 structure_value_addr);
2309 if (temp != (rtx) (size_t) - 1)
2313 /* Figure out the amount to which the stack should be aligned. */
2314 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2317 struct cgraph_rtl_info *i = cgraph_rtl_info (fndecl);
2318 if (i && i->preferred_incoming_stack_boundary)
2319 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2322 /* Operand 0 is a pointer-to-function; get the type of the function. */
2323 funtype = TREE_TYPE (addr);
2324 if (! POINTER_TYPE_P (funtype))
2326 funtype = TREE_TYPE (funtype);
2328 /* See if this is a call to a function that can return more than once
2329 or a call to longjmp or malloc. */
2330 flags |= special_function_p (fndecl, flags);
2332 if (flags & ECF_MAY_BE_ALLOCA)
2333 current_function_calls_alloca = 1;
2335 /* If struct_value_rtx is 0, it means pass the address
2336 as if it were an extra parameter. */
2337 if (structure_value_addr && struct_value_rtx == 0)
2339 /* If structure_value_addr is a REG other than
2340 virtual_outgoing_args_rtx, we can use always use it. If it
2341 is not a REG, we must always copy it into a register.
2342 If it is virtual_outgoing_args_rtx, we must copy it to another
2343 register in some cases. */
2344 rtx temp = (GET_CODE (structure_value_addr) != REG
2345 || (ACCUMULATE_OUTGOING_ARGS
2346 && stack_arg_under_construction
2347 && structure_value_addr == virtual_outgoing_args_rtx)
2348 ? copy_addr_to_reg (structure_value_addr)
2349 : structure_value_addr);
2352 = tree_cons (error_mark_node,
2353 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2356 structure_value_addr_parm = 1;
2359 /* Count the arguments and set NUM_ACTUALS. */
2360 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2363 /* Compute number of named args.
2364 Normally, don't include the last named arg if anonymous args follow.
2365 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2366 (If no anonymous args follow, the result of list_length is actually
2367 one too large. This is harmless.)
2369 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2370 zero, this machine will be able to place unnamed args that were
2371 passed in registers into the stack. So treat all args as named.
2372 This allows the insns emitting for a specific argument list to be
2373 independent of the function declaration.
2375 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2376 reliable way to pass unnamed args in registers, so we must force
2377 them into memory. */
2379 if ((STRICT_ARGUMENT_NAMING
2380 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2381 && TYPE_ARG_TYPES (funtype) != 0)
2383 = (list_length (TYPE_ARG_TYPES (funtype))
2384 /* Don't include the last named arg. */
2385 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2386 /* Count the struct value address, if it is passed as a parm. */
2387 + structure_value_addr_parm);
2389 /* If we know nothing, treat all args as named. */
2390 n_named_args = num_actuals;
2392 /* Start updating where the next arg would go.
2394 On some machines (such as the PA) indirect calls have a different
2395 calling convention than normal calls. The last argument in
2396 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2398 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, fndecl);
2400 /* Make a vector to hold all the information about each arg. */
2401 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
2402 memset ((char *) args, 0, num_actuals * sizeof (struct arg_data));
2404 /* Build up entries in the ARGS array, compute the size of the
2405 arguments into ARGS_SIZE, etc. */
2406 initialize_argument_information (num_actuals, args, &args_size,
2407 n_named_args, actparms, fndecl,
2408 &args_so_far, reg_parm_stack_space,
2409 &old_stack_level, &old_pending_adj,
2410 &must_preallocate, &flags);
2414 /* If this function requires a variable-sized argument list, don't
2415 try to make a cse'able block for this call. We may be able to
2416 do this eventually, but it is too complicated to keep track of
2417 what insns go in the cse'able block and which don't. */
2419 flags &= ~ECF_LIBCALL_BLOCK;
2420 must_preallocate = 1;
2423 /* Now make final decision about preallocating stack space. */
2424 must_preallocate = finalize_must_preallocate (must_preallocate,
2428 /* If the structure value address will reference the stack pointer, we
2429 must stabilize it. We don't need to do this if we know that we are
2430 not going to adjust the stack pointer in processing this call. */
2432 if (structure_value_addr
2433 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2434 || reg_mentioned_p (virtual_outgoing_args_rtx,
2435 structure_value_addr))
2437 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2438 structure_value_addr = copy_to_reg (structure_value_addr);
2440 /* Tail calls can make things harder to debug, and we're traditionally
2441 pushed these optimizations into -O2. Don't try if we're already
2442 expanding a call, as that means we're an argument. Don't try if
2443 there's cleanups, as we know there's code to follow the call.
2445 If rtx_equal_function_value_matters is false, that means we've
2446 finished with regular parsing. Which means that some of the
2447 machinery we use to generate tail-calls is no longer in place.
2448 This is most often true of sjlj-exceptions, which we couldn't
2449 tail-call to anyway. */
2451 if (currently_expanding_call++ != 0
2452 || !flag_optimize_sibling_calls
2453 || !rtx_equal_function_value_matters
2454 || any_pending_cleanups (1)
2456 try_tail_call = try_tail_recursion = 0;
2458 /* Tail recursion fails, when we are not dealing with recursive calls. */
2459 if (!try_tail_recursion
2460 || TREE_CODE (addr) != ADDR_EXPR
2461 || TREE_OPERAND (addr, 0) != current_function_decl)
2462 try_tail_recursion = 0;
2464 /* Rest of purposes for tail call optimizations to fail. */
2466 #ifdef HAVE_sibcall_epilogue
2467 !HAVE_sibcall_epilogue
2472 /* Doing sibling call optimization needs some work, since
2473 structure_value_addr can be allocated on the stack.
2474 It does not seem worth the effort since few optimizable
2475 sibling calls will return a structure. */
2476 || structure_value_addr != NULL_RTX
2477 /* Check whether the target is able to optimize the call
2479 || !(*targetm.function_ok_for_sibcall) (fndecl, exp)
2480 /* Functions that do not return exactly once may not be sibcall
2482 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP | ECF_NORETURN))
2483 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2484 /* If the called function is nested in the current one, it might access
2485 some of the caller's arguments, but could clobber them beforehand if
2486 the argument areas are shared. */
2487 || (fndecl && decl_function_context (fndecl) == current_function_decl)
2488 /* If this function requires more stack slots than the current
2489 function, we cannot change it into a sibling call. */
2490 || args_size.constant > current_function_args_size
2491 /* If the callee pops its own arguments, then it must pop exactly
2492 the same number of arguments as the current function. */
2493 || RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2494 != RETURN_POPS_ARGS (current_function_decl,
2495 TREE_TYPE (current_function_decl),
2496 current_function_args_size))
2499 if (try_tail_call || try_tail_recursion)
2502 actparms = NULL_TREE;
2503 /* Ok, we're going to give the tail call the old college try.
2504 This means we're going to evaluate the function arguments
2505 up to three times. There are two degrees of badness we can
2506 encounter, those that can be unsaved and those that can't.
2507 (See unsafe_for_reeval commentary for details.)
2509 Generate a new argument list. Pass safe arguments through
2510 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2511 For hard badness, evaluate them now and put their resulting
2512 rtx in a temporary VAR_DECL.
2514 initialize_argument_information has ordered the array for the
2515 order to be pushed, and we must remember this when reconstructing
2516 the original argument order. */
2518 if (PUSH_ARGS_REVERSED)
2527 i = num_actuals - 1;
2531 for (; i != end; i += inc)
2533 args[i].tree_value = fix_unsafe_tree (args[i].tree_value);
2534 /* We need to build actparms for optimize_tail_recursion. We can
2535 safely trash away TREE_PURPOSE, since it is unused by this
2537 if (try_tail_recursion)
2538 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2540 /* Do the same for the function address if it is an expression. */
2542 addr = fix_unsafe_tree (addr);
2543 /* Expanding one of those dangerous arguments could have added
2544 cleanups, but otherwise give it a whirl. */
2545 if (any_pending_cleanups (1))
2546 try_tail_call = try_tail_recursion = 0;
2549 /* Generate a tail recursion sequence when calling ourselves. */
2551 if (try_tail_recursion)
2553 /* We want to emit any pending stack adjustments before the tail
2554 recursion "call". That way we know any adjustment after the tail
2555 recursion call can be ignored if we indeed use the tail recursion
2557 int save_pending_stack_adjust = pending_stack_adjust;
2558 int save_stack_pointer_delta = stack_pointer_delta;
2560 /* Emit any queued insns now; otherwise they would end up in
2561 only one of the alternates. */
2564 /* Use a new sequence to hold any RTL we generate. We do not even
2565 know if we will use this RTL yet. The final decision can not be
2566 made until after RTL generation for the entire function is
2569 /* If expanding any of the arguments creates cleanups, we can't
2570 do a tailcall. So, we'll need to pop the pending cleanups
2571 list. If, however, all goes well, and there are no cleanups
2572 then the call to expand_start_target_temps will have no
2574 expand_start_target_temps ();
2575 if (optimize_tail_recursion (actparms, get_last_insn ()))
2577 if (any_pending_cleanups (1))
2578 try_tail_call = try_tail_recursion = 0;
2580 tail_recursion_insns = get_insns ();
2582 expand_end_target_temps ();
2585 /* Restore the original pending stack adjustment for the sibling and
2586 normal call cases below. */
2587 pending_stack_adjust = save_pending_stack_adjust;
2588 stack_pointer_delta = save_stack_pointer_delta;
2591 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2593 /* A fork duplicates the profile information, and an exec discards
2594 it. We can't rely on fork/exec to be paired. So write out the
2595 profile information we have gathered so far, and clear it. */
2596 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2597 is subject to race conditions, just as with multithreaded
2600 emit_library_call (gcov_flush_libfunc, LCT_ALWAYS_RETURN, VOIDmode, 0);
2603 /* Ensure current function's preferred stack boundary is at least
2604 what we need. We don't have to increase alignment for recursive
2606 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2607 && fndecl != current_function_decl)
2608 cfun->preferred_stack_boundary = preferred_stack_boundary;
2609 if (fndecl == current_function_decl)
2610 cfun->recursive_call_emit = true;
2612 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2614 function_call_count++;
2616 /* We want to make two insn chains; one for a sibling call, the other
2617 for a normal call. We will select one of the two chains after
2618 initial RTL generation is complete. */
2619 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2621 int sibcall_failure = 0;
2622 /* We want to emit any pending stack adjustments before the tail
2623 recursion "call". That way we know any adjustment after the tail
2624 recursion call can be ignored if we indeed use the tail recursion
2626 int save_pending_stack_adjust = 0;
2627 int save_stack_pointer_delta = 0;
2629 rtx before_call, next_arg_reg;
2633 /* Emit any queued insns now; otherwise they would end up in
2634 only one of the alternates. */
2637 /* State variables we need to save and restore between
2639 save_pending_stack_adjust = pending_stack_adjust;
2640 save_stack_pointer_delta = stack_pointer_delta;
2643 flags &= ~ECF_SIBCALL;
2645 flags |= ECF_SIBCALL;
2647 /* Other state variables that we must reinitialize each time
2648 through the loop (that are not initialized by the loop itself). */
2652 /* Start a new sequence for the normal call case.
2654 From this point on, if the sibling call fails, we want to set
2655 sibcall_failure instead of continuing the loop. */
2660 /* We know at this point that there are not currently any
2661 pending cleanups. If, however, in the process of evaluating
2662 the arguments we were to create some, we'll need to be
2663 able to get rid of them. */
2664 expand_start_target_temps ();
2667 /* Don't let pending stack adjusts add up to too much.
2668 Also, do all pending adjustments now if there is any chance
2669 this might be a call to alloca or if we are expanding a sibling
2670 call sequence or if we are calling a function that is to return
2671 with stack pointer depressed. */
2672 if (pending_stack_adjust >= 32
2673 || (pending_stack_adjust > 0
2674 && (flags & (ECF_MAY_BE_ALLOCA | ECF_SP_DEPRESSED)))
2676 do_pending_stack_adjust ();
2678 /* When calling a const function, we must pop the stack args right away,
2679 so that the pop is deleted or moved with the call. */
2680 if (pass && (flags & ECF_LIBCALL_BLOCK))
2683 #ifdef FINAL_REG_PARM_STACK_SPACE
2684 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2687 /* Precompute any arguments as needed. */
2689 precompute_arguments (flags, num_actuals, args);
2691 /* Now we are about to start emitting insns that can be deleted
2692 if a libcall is deleted. */
2693 if (pass && (flags & (ECF_LIBCALL_BLOCK | ECF_MALLOC)))
2696 adjusted_args_size = args_size;
2697 /* Compute the actual size of the argument block required. The variable
2698 and constant sizes must be combined, the size may have to be rounded,
2699 and there may be a minimum required size. When generating a sibcall
2700 pattern, do not round up, since we'll be re-using whatever space our
2702 unadjusted_args_size
2703 = compute_argument_block_size (reg_parm_stack_space,
2704 &adjusted_args_size,
2706 : preferred_stack_boundary));
2708 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2710 /* The argument block when performing a sibling call is the
2711 incoming argument block. */
2714 argblock = virtual_incoming_args_rtx;
2716 #ifdef STACK_GROWS_DOWNWARD
2717 = plus_constant (argblock, current_function_pretend_args_size);
2719 = plus_constant (argblock, -current_function_pretend_args_size);
2721 stored_args_map = sbitmap_alloc (args_size.constant);
2722 sbitmap_zero (stored_args_map);
2725 /* If we have no actual push instructions, or shouldn't use them,
2726 make space for all args right now. */
2727 else if (adjusted_args_size.var != 0)
2729 if (old_stack_level == 0)
2731 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2732 old_stack_pointer_delta = stack_pointer_delta;
2733 old_pending_adj = pending_stack_adjust;
2734 pending_stack_adjust = 0;
2735 /* stack_arg_under_construction says whether a stack arg is
2736 being constructed at the old stack level. Pushing the stack
2737 gets a clean outgoing argument block. */
2738 old_stack_arg_under_construction = stack_arg_under_construction;
2739 stack_arg_under_construction = 0;
2741 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2745 /* Note that we must go through the motions of allocating an argument
2746 block even if the size is zero because we may be storing args
2747 in the area reserved for register arguments, which may be part of
2750 int needed = adjusted_args_size.constant;
2752 /* Store the maximum argument space used. It will be pushed by
2753 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2756 if (needed > current_function_outgoing_args_size)
2757 current_function_outgoing_args_size = needed;
2759 if (must_preallocate)
2761 if (ACCUMULATE_OUTGOING_ARGS)
2763 /* Since the stack pointer will never be pushed, it is
2764 possible for the evaluation of a parm to clobber
2765 something we have already written to the stack.
2766 Since most function calls on RISC machines do not use
2767 the stack, this is uncommon, but must work correctly.
2769 Therefore, we save any area of the stack that was already
2770 written and that we are using. Here we set up to do this
2771 by making a new stack usage map from the old one. The
2772 actual save will be done by store_one_arg.
2774 Another approach might be to try to reorder the argument
2775 evaluations to avoid this conflicting stack usage. */
2777 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2778 /* Since we will be writing into the entire argument area,
2779 the map must be allocated for its entire size, not just
2780 the part that is the responsibility of the caller. */
2781 needed += reg_parm_stack_space;
2784 #ifdef ARGS_GROW_DOWNWARD
2785 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2788 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2792 = (char *) alloca (highest_outgoing_arg_in_use);
2794 if (initial_highest_arg_in_use)
2795 memcpy (stack_usage_map, initial_stack_usage_map,
2796 initial_highest_arg_in_use);
2798 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2799 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2800 (highest_outgoing_arg_in_use
2801 - initial_highest_arg_in_use));
2804 /* The address of the outgoing argument list must not be
2805 copied to a register here, because argblock would be left
2806 pointing to the wrong place after the call to
2807 allocate_dynamic_stack_space below. */
2809 argblock = virtual_outgoing_args_rtx;
2813 if (inhibit_defer_pop == 0)
2815 /* Try to reuse some or all of the pending_stack_adjust
2816 to get this space. */
2818 = (combine_pending_stack_adjustment_and_call
2819 (unadjusted_args_size,
2820 &adjusted_args_size,
2821 preferred_unit_stack_boundary));
2823 /* combine_pending_stack_adjustment_and_call computes
2824 an adjustment before the arguments are allocated.
2825 Account for them and see whether or not the stack
2826 needs to go up or down. */
2827 needed = unadjusted_args_size - needed;
2831 /* We're releasing stack space. */
2832 /* ??? We can avoid any adjustment at all if we're
2833 already aligned. FIXME. */
2834 pending_stack_adjust = -needed;
2835 do_pending_stack_adjust ();
2839 /* We need to allocate space. We'll do that in
2840 push_block below. */
2841 pending_stack_adjust = 0;
2844 /* Special case this because overhead of `push_block' in
2845 this case is non-trivial. */
2847 argblock = virtual_outgoing_args_rtx;
2849 argblock = push_block (GEN_INT (needed), 0, 0);
2851 /* We only really need to call `copy_to_reg' in the case
2852 where push insns are going to be used to pass ARGBLOCK
2853 to a function call in ARGS. In that case, the stack
2854 pointer changes value from the allocation point to the
2855 call point, and hence the value of
2856 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2857 as well always do it. */
2858 argblock = copy_to_reg (argblock);
2863 if (ACCUMULATE_OUTGOING_ARGS)
2865 /* The save/restore code in store_one_arg handles all
2866 cases except one: a constructor call (including a C
2867 function returning a BLKmode struct) to initialize
2869 if (stack_arg_under_construction)
2871 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2872 rtx push_size = GEN_INT (reg_parm_stack_space
2873 + adjusted_args_size.constant);
2875 rtx push_size = GEN_INT (adjusted_args_size.constant);
2877 if (old_stack_level == 0)
2879 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2881 old_stack_pointer_delta = stack_pointer_delta;
2882 old_pending_adj = pending_stack_adjust;
2883 pending_stack_adjust = 0;
2884 /* stack_arg_under_construction says whether a stack
2885 arg is being constructed at the old stack level.
2886 Pushing the stack gets a clean outgoing argument
2888 old_stack_arg_under_construction
2889 = stack_arg_under_construction;
2890 stack_arg_under_construction = 0;
2891 /* Make a new map for the new argument list. */
2892 stack_usage_map = (char *)
2893 alloca (highest_outgoing_arg_in_use);
2894 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2895 highest_outgoing_arg_in_use = 0;
2897 allocate_dynamic_stack_space (push_size, NULL_RTX,
2901 /* If argument evaluation might modify the stack pointer,
2902 copy the address of the argument list to a register. */
2903 for (i = 0; i < num_actuals; i++)
2904 if (args[i].pass_on_stack)
2906 argblock = copy_addr_to_reg (argblock);
2911 compute_argument_addresses (args, argblock, num_actuals);
2913 /* If we push args individually in reverse order, perform stack alignment
2914 before the first push (the last arg). */
2915 if (PUSH_ARGS_REVERSED && argblock == 0
2916 && adjusted_args_size.constant != unadjusted_args_size)
2918 /* When the stack adjustment is pending, we get better code
2919 by combining the adjustments. */
2920 if (pending_stack_adjust
2921 && ! (flags & ECF_LIBCALL_BLOCK)
2922 && ! inhibit_defer_pop)
2924 pending_stack_adjust
2925 = (combine_pending_stack_adjustment_and_call
2926 (unadjusted_args_size,
2927 &adjusted_args_size,
2928 preferred_unit_stack_boundary));
2929 do_pending_stack_adjust ();
2931 else if (argblock == 0)
2932 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2933 - unadjusted_args_size));
2935 /* Now that the stack is properly aligned, pops can't safely
2936 be deferred during the evaluation of the arguments. */
2939 funexp = rtx_for_function_call (fndecl, addr);
2941 /* Figure out the register where the value, if any, will come back. */
2943 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2944 && ! structure_value_addr)
2946 if (pcc_struct_value)
2947 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2948 fndecl, (pass == 0));
2950 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2953 /* Precompute all register parameters. It isn't safe to compute anything
2954 once we have started filling any specific hard regs. */
2955 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2957 #ifdef REG_PARM_STACK_SPACE
2958 /* Save the fixed argument area if it's part of the caller's frame and
2959 is clobbered by argument setup for this call. */
2960 if (ACCUMULATE_OUTGOING_ARGS && pass)
2961 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2962 &low_to_save, &high_to_save);
2965 /* Now store (and compute if necessary) all non-register parms.
2966 These come before register parms, since they can require block-moves,
2967 which could clobber the registers used for register parms.
2968 Parms which have partial registers are not stored here,
2969 but we do preallocate space here if they want that. */
2971 for (i = 0; i < num_actuals; i++)
2972 if (args[i].reg == 0 || args[i].pass_on_stack)
2974 rtx before_arg = get_last_insn ();
2976 if (store_one_arg (&args[i], argblock, flags,
2977 adjusted_args_size.var != 0,
2978 reg_parm_stack_space)
2980 && check_sibcall_argument_overlap (before_arg,
2982 sibcall_failure = 1;
2985 /* If we have a parm that is passed in registers but not in memory
2986 and whose alignment does not permit a direct copy into registers,
2987 make a group of pseudos that correspond to each register that we
2989 if (STRICT_ALIGNMENT)
2990 store_unaligned_arguments_into_pseudos (args, num_actuals);
2992 /* Now store any partially-in-registers parm.
2993 This is the last place a block-move can happen. */
2995 for (i = 0; i < num_actuals; i++)
2996 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2998 rtx before_arg = get_last_insn ();
3000 if (store_one_arg (&args[i], argblock, flags,
3001 adjusted_args_size.var != 0,
3002 reg_parm_stack_space)
3004 && check_sibcall_argument_overlap (before_arg,
3006 sibcall_failure = 1;
3009 /* If we pushed args in forward order, perform stack alignment
3010 after pushing the last arg. */
3011 if (!PUSH_ARGS_REVERSED && argblock == 0)
3012 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3013 - unadjusted_args_size));
3015 /* If register arguments require space on the stack and stack space
3016 was not preallocated, allocate stack space here for arguments
3017 passed in registers. */
3018 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3019 if (!ACCUMULATE_OUTGOING_ARGS
3020 && must_preallocate == 0 && reg_parm_stack_space > 0)
3021 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3024 /* Pass the function the address in which to return a
3026 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3028 emit_move_insn (struct_value_rtx,
3030 force_operand (structure_value_addr,
3033 if (GET_CODE (struct_value_rtx) == REG)
3034 use_reg (&call_fusage, struct_value_rtx);
3037 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3038 reg_parm_seen, pass == 0);
3040 load_register_parameters (args, num_actuals, &call_fusage, flags,
3041 pass == 0, &sibcall_failure);
3043 /* Perform postincrements before actually calling the function. */
3046 /* Save a pointer to the last insn before the call, so that we can
3047 later safely search backwards to find the CALL_INSN. */
3048 before_call = get_last_insn ();
3050 /* Set up next argument register. For sibling calls on machines
3051 with register windows this should be the incoming register. */
3052 #ifdef FUNCTION_INCOMING_ARG
3054 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3058 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3061 /* All arguments and registers used for the call must be set up by
3064 /* Stack must be properly aligned now. */
3065 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3068 /* Generate the actual call instruction. */
3069 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3070 adjusted_args_size.constant, struct_value_size,
3071 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3072 flags, & args_so_far);
3074 /* If call is cse'able, make appropriate pair of reg-notes around it.
3075 Test valreg so we don't crash; may safely ignore `const'
3076 if return type is void. Disable for PARALLEL return values, because
3077 we have no way to move such values into a pseudo register. */
3078 if (pass && (flags & ECF_LIBCALL_BLOCK))
3082 if (valreg == 0 || GET_CODE (valreg) == PARALLEL)
3084 insns = get_insns ();
3091 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3093 /* Mark the return value as a pointer if needed. */
3094 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3095 mark_reg_pointer (temp,
3096 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3098 /* Construct an "equal form" for the value which mentions all the
3099 arguments in order as well as the function name. */
3100 for (i = 0; i < num_actuals; i++)
3101 note = gen_rtx_EXPR_LIST (VOIDmode,
3102 args[i].initial_value, note);
3103 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3105 insns = get_insns ();
3108 if (flags & ECF_PURE)
3109 note = gen_rtx_EXPR_LIST (VOIDmode,
3110 gen_rtx_USE (VOIDmode,
3111 gen_rtx_MEM (BLKmode,
3112 gen_rtx_SCRATCH (VOIDmode))),
3115 emit_libcall_block (insns, temp, valreg, note);
3120 else if (pass && (flags & ECF_MALLOC))
3122 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3125 /* The return value from a malloc-like function is a pointer. */
3126 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3127 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3129 emit_move_insn (temp, valreg);
3131 /* The return value from a malloc-like function can not alias
3133 last = get_last_insn ();
3135 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3137 /* Write out the sequence. */
3138 insns = get_insns ();
3144 /* For calls to `setjmp', etc., inform flow.c it should complain
3145 if nonvolatile values are live. For functions that cannot return,
3146 inform flow that control does not fall through. */
3148 if ((flags & (ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3150 /* The barrier must be emitted
3151 immediately after the CALL_INSN. Some ports emit more
3152 than just a CALL_INSN above, so we must search for it here. */
3154 rtx last = get_last_insn ();
3155 while (GET_CODE (last) != CALL_INSN)
3157 last = PREV_INSN (last);
3158 /* There was no CALL_INSN? */
3159 if (last == before_call)
3163 emit_barrier_after (last);
3166 if (flags & ECF_LONGJMP)
3167 current_function_calls_longjmp = 1;
3169 /* If this function is returning into a memory location marked as
3170 readonly, it means it is initializing that location. But we normally
3171 treat functions as not clobbering such locations, so we need to
3172 specify that this one does. */
3173 if (target != 0 && GET_CODE (target) == MEM
3174 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
3175 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
3177 /* If value type not void, return an rtx for the value. */
3179 /* If there are cleanups to be called, don't use a hard reg as target.
3180 We need to double check this and see if it matters anymore. */
3181 if (any_pending_cleanups (1))
3183 if (target && REG_P (target)
3184 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3186 sibcall_failure = 1;
3189 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3191 target = const0_rtx;
3192 else if (structure_value_addr)
3194 if (target == 0 || GET_CODE (target) != MEM)
3197 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3198 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3199 structure_value_addr));
3200 set_mem_attributes (target, exp, 1);
3203 else if (pcc_struct_value)
3205 /* This is the special C++ case where we need to
3206 know what the true target was. We take care to
3207 never use this value more than once in one expression. */
3208 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3209 copy_to_reg (valreg));
3210 set_mem_attributes (target, exp, 1);
3212 /* Handle calls that return values in multiple non-contiguous locations.
3213 The Irix 6 ABI has examples of this. */
3214 else if (GET_CODE (valreg) == PARALLEL)
3218 /* This will only be assigned once, so it can be readonly. */
3219 tree nt = build_qualified_type (TREE_TYPE (exp),
3220 (TYPE_QUALS (TREE_TYPE (exp))
3221 | TYPE_QUAL_CONST));
3223 target = assign_temp (nt, 0, 1, 1);
3224 preserve_temp_slots (target);
3227 if (! rtx_equal_p (target, valreg))
3228 emit_group_store (target, valreg,
3229 int_size_in_bytes (TREE_TYPE (exp)));
3231 /* We can not support sibling calls for this case. */
3232 sibcall_failure = 1;
3235 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3236 && GET_MODE (target) == GET_MODE (valreg))
3238 /* TARGET and VALREG cannot be equal at this point because the
3239 latter would not have REG_FUNCTION_VALUE_P true, while the
3240 former would if it were referring to the same register.
3242 If they refer to the same register, this move will be a no-op,
3243 except when function inlining is being done. */
3244 emit_move_insn (target, valreg);
3246 /* If we are setting a MEM, this code must be executed. Since it is
3247 emitted after the call insn, sibcall optimization cannot be
3248 performed in that case. */
3249 if (GET_CODE (target) == MEM)
3250 sibcall_failure = 1;
3252 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3254 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3256 /* We can not support sibling calls for this case. */
3257 sibcall_failure = 1;
3260 target = copy_to_reg (valreg);
3262 #ifdef PROMOTE_FUNCTION_RETURN
3263 /* If we promoted this return value, make the proper SUBREG. TARGET
3264 might be const0_rtx here, so be careful. */
3265 if (GET_CODE (target) == REG
3266 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3267 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3269 tree type = TREE_TYPE (exp);
3270 int unsignedp = TREE_UNSIGNED (type);
3273 /* If we don't promote as expected, something is wrong. */
3274 if (GET_MODE (target)
3275 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3278 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3279 && GET_MODE_SIZE (GET_MODE (target))
3280 > GET_MODE_SIZE (TYPE_MODE (type)))
3282 offset = GET_MODE_SIZE (GET_MODE (target))
3283 - GET_MODE_SIZE (TYPE_MODE (type));
3284 if (! BYTES_BIG_ENDIAN)
3285 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3286 else if (! WORDS_BIG_ENDIAN)
3287 offset %= UNITS_PER_WORD;
3289 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3290 SUBREG_PROMOTED_VAR_P (target) = 1;
3291 SUBREG_PROMOTED_UNSIGNED_SET (target, unsignedp);
3295 /* If size of args is variable or this was a constructor call for a stack
3296 argument, restore saved stack-pointer value. */
3298 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3300 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3301 stack_pointer_delta = old_stack_pointer_delta;
3302 pending_stack_adjust = old_pending_adj;
3303 stack_arg_under_construction = old_stack_arg_under_construction;
3304 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3305 stack_usage_map = initial_stack_usage_map;
3306 sibcall_failure = 1;
3308 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3310 #ifdef REG_PARM_STACK_SPACE
3312 restore_fixed_argument_area (save_area, argblock,
3313 high_to_save, low_to_save);
3316 /* If we saved any argument areas, restore them. */
3317 for (i = 0; i < num_actuals; i++)
3318 if (args[i].save_area)
3320 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3322 = gen_rtx_MEM (save_mode,
3323 memory_address (save_mode,
3324 XEXP (args[i].stack_slot, 0)));
3326 if (save_mode != BLKmode)
3327 emit_move_insn (stack_area, args[i].save_area);
3329 emit_block_move (stack_area, args[i].save_area,
3330 GEN_INT (args[i].locate.size.constant),
3331 BLOCK_OP_CALL_PARM);
3334 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3335 stack_usage_map = initial_stack_usage_map;
3338 /* If this was alloca, record the new stack level for nonlocal gotos.
3339 Check for the handler slots since we might not have a save area
3340 for non-local gotos. */
3342 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3343 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3345 /* Free up storage we no longer need. */
3346 for (i = 0; i < num_actuals; ++i)
3347 if (args[i].aligned_regs)
3348 free (args[i].aligned_regs);
3352 /* Undo the fake expand_start_target_temps we did earlier. If
3353 there had been any cleanups created, we've already set
3355 expand_end_target_temps ();
3358 insns = get_insns ();
3363 tail_call_insns = insns;
3365 /* Restore the pending stack adjustment now that we have
3366 finished generating the sibling call sequence. */
3368 pending_stack_adjust = save_pending_stack_adjust;
3369 stack_pointer_delta = save_stack_pointer_delta;
3371 /* Prepare arg structure for next iteration. */
3372 for (i = 0; i < num_actuals; i++)
3375 args[i].aligned_regs = 0;
3379 sbitmap_free (stored_args_map);
3383 normal_call_insns = insns;
3385 /* Verify that we've deallocated all the stack we used. */
3386 if (old_stack_allocated !=
3387 stack_pointer_delta - pending_stack_adjust)
3391 /* If something prevents making this a sibling call,
3392 zero out the sequence. */
3393 if (sibcall_failure)
3394 tail_call_insns = NULL_RTX;
3397 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3398 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3399 can happen if the arguments to this function call an inline
3400 function who's expansion contains another CALL_PLACEHOLDER.
3402 If there are any C_Ps in any of these sequences, replace them
3403 with their normal call. */
3405 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3406 if (GET_CODE (insn) == CALL_INSN
3407 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3408 replace_call_placeholder (insn, sibcall_use_normal);
3410 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3411 if (GET_CODE (insn) == CALL_INSN
3412 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3413 replace_call_placeholder (insn, sibcall_use_normal);
3415 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3416 if (GET_CODE (insn) == CALL_INSN
3417 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3418 replace_call_placeholder (insn, sibcall_use_normal);
3420 /* If this was a potential tail recursion site, then emit a
3421 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3422 One of them will be selected later. */
3423 if (tail_recursion_insns || tail_call_insns)
3425 /* The tail recursion label must be kept around. We could expose
3426 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3427 and makes determining true tail recursion sites difficult.
3429 So we set LABEL_PRESERVE_P here, then clear it when we select
3430 one of the call sequences after rtl generation is complete. */
3431 if (tail_recursion_insns)
3432 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3433 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3435 tail_recursion_insns,
3436 tail_recursion_label));
3439 emit_insn (normal_call_insns);
3441 currently_expanding_call--;
3443 /* If this function returns with the stack pointer depressed, ensure
3444 this block saves and restores the stack pointer, show it was
3445 changed, and adjust for any outgoing arg space. */
3446 if (flags & ECF_SP_DEPRESSED)
3448 clear_pending_stack_adjust ();
3449 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3450 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3451 save_stack_pointer ();
3457 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3458 The RETVAL parameter specifies whether return value needs to be saved, other
3459 parameters are documented in the emit_library_call function below. */
3462 emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3466 enum libcall_type fn_type;
3467 enum machine_mode outmode;
3471 /* Total size in bytes of all the stack-parms scanned so far. */
3472 struct args_size args_size;
3473 /* Size of arguments before any adjustments (such as rounding). */
3474 struct args_size original_args_size;
3480 CUMULATIVE_ARGS args_so_far;
3484 enum machine_mode mode;
3487 struct locate_and_pad_arg_data locate;
3491 int old_inhibit_defer_pop = inhibit_defer_pop;
3492 rtx call_fusage = 0;
3495 int pcc_struct_value = 0;
3496 int struct_value_size = 0;
3498 int reg_parm_stack_space = 0;
3501 tree tfom; /* type_for_mode (outmode, 0) */
3503 #ifdef REG_PARM_STACK_SPACE
3504 /* Define the boundary of the register parm stack space that needs to be
3506 int low_to_save, high_to_save;
3507 rtx save_area = 0; /* Place that it is saved. */
3510 /* Size of the stack reserved for parameter registers. */
3511 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3512 char *initial_stack_usage_map = stack_usage_map;
3514 #ifdef REG_PARM_STACK_SPACE
3515 #ifdef MAYBE_REG_PARM_STACK_SPACE
3516 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3518 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3522 /* By default, library functions can not throw. */
3523 flags = ECF_NOTHROW;
3535 case LCT_CONST_MAKE_BLOCK:
3536 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
3538 case LCT_PURE_MAKE_BLOCK:
3539 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
3542 flags |= ECF_NORETURN;
3545 flags = ECF_NORETURN;
3547 case LCT_ALWAYS_RETURN:
3548 flags = ECF_ALWAYS_RETURN;
3550 case LCT_RETURNS_TWICE:
3551 flags = ECF_RETURNS_TWICE;
3556 /* Ensure current function's preferred stack boundary is at least
3558 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3559 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3561 /* If this kind of value comes back in memory,
3562 decide where in memory it should come back. */
3563 if (outmode != VOIDmode)
3565 tfom = (*lang_hooks.types.type_for_mode) (outmode, 0);
3566 if (aggregate_value_p (tfom))
3568 #ifdef PCC_STATIC_STRUCT_RETURN
3570 = hard_function_value (build_pointer_type (tfom), 0, 0);
3571 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3572 pcc_struct_value = 1;
3574 value = gen_reg_rtx (outmode);
3575 #else /* not PCC_STATIC_STRUCT_RETURN */
3576 struct_value_size = GET_MODE_SIZE (outmode);
3577 if (value != 0 && GET_CODE (value) == MEM)
3580 mem_value = assign_temp (tfom, 0, 1, 1);
3582 /* This call returns a big structure. */
3583 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3587 tfom = void_type_node;
3589 /* ??? Unfinished: must pass the memory address as an argument. */
3591 /* Copy all the libcall-arguments out of the varargs data
3592 and into a vector ARGVEC.
3594 Compute how to pass each argument. We only support a very small subset
3595 of the full argument passing conventions to limit complexity here since
3596 library functions shouldn't have many args. */
3598 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3599 memset ((char *) argvec, 0, (nargs + 1) * sizeof (struct arg));
3601 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3602 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3604 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3607 args_size.constant = 0;
3612 /* Now we are about to start emitting insns that can be deleted
3613 if a libcall is deleted. */
3614 if (flags & ECF_LIBCALL_BLOCK)
3619 /* If there's a structure value address to be passed,
3620 either pass it in the special place, or pass it as an extra argument. */
3621 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3623 rtx addr = XEXP (mem_value, 0);
3626 /* Make sure it is a reasonable operand for a move or push insn. */
3627 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3628 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3629 addr = force_operand (addr, NULL_RTX);
3631 argvec[count].value = addr;
3632 argvec[count].mode = Pmode;
3633 argvec[count].partial = 0;
3635 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3636 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3637 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3641 locate_and_pad_parm (Pmode, NULL_TREE,
3642 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3645 argvec[count].reg != 0,
3647 0, NULL_TREE, &args_size, &argvec[count].locate);
3649 if (argvec[count].reg == 0 || argvec[count].partial != 0
3650 || reg_parm_stack_space > 0)
3651 args_size.constant += argvec[count].locate.size.constant;
3653 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3658 for (; count < nargs; count++)
3660 rtx val = va_arg (p, rtx);
3661 enum machine_mode mode = va_arg (p, enum machine_mode);
3663 /* We cannot convert the arg value to the mode the library wants here;
3664 must do it earlier where we know the signedness of the arg. */
3666 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3669 /* On some machines, there's no way to pass a float to a library fcn.
3670 Pass it as a double instead. */
3671 #ifdef LIBGCC_NEEDS_DOUBLE
3672 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3673 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3676 /* There's no need to call protect_from_queue, because
3677 either emit_move_insn or emit_push_insn will do that. */
3679 /* Make sure it is a reasonable operand for a move or push insn. */
3680 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3681 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3682 val = force_operand (val, NULL_RTX);
3684 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3685 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3689 #ifdef FUNCTION_ARG_CALLEE_COPIES
3690 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3695 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3696 functions, so we have to pretend this isn't such a function. */
3697 if (flags & ECF_LIBCALL_BLOCK)
3699 rtx insns = get_insns ();
3703 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3705 /* If this was a CONST function, it is now PURE since
3706 it now reads memory. */
3707 if (flags & ECF_CONST)
3709 flags &= ~ECF_CONST;
3713 if (GET_MODE (val) == MEM && ! must_copy)
3717 slot = assign_temp ((*lang_hooks.types.type_for_mode) (mode, 0),
3719 emit_move_insn (slot, val);
3723 tree type = (*lang_hooks.types.type_for_mode) (mode, 0);
3726 = gen_rtx_MEM (mode,
3727 expand_expr (build1 (ADDR_EXPR,
3728 build_pointer_type (type),
3729 make_tree (type, val)),
3730 NULL_RTX, VOIDmode, 0));
3733 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3734 gen_rtx_USE (VOIDmode, slot),
3737 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3738 gen_rtx_CLOBBER (VOIDmode,
3743 val = force_operand (XEXP (slot, 0), NULL_RTX);
3747 argvec[count].value = val;
3748 argvec[count].mode = mode;
3750 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3752 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3753 argvec[count].partial
3754 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3756 argvec[count].partial = 0;
3759 locate_and_pad_parm (mode, NULL_TREE,
3760 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3763 argvec[count].reg != 0,
3765 argvec[count].partial,
3766 NULL_TREE, &args_size, &argvec[count].locate);
3768 if (argvec[count].locate.size.var)
3771 if (argvec[count].reg == 0 || argvec[count].partial != 0
3772 || reg_parm_stack_space > 0)
3773 args_size.constant += argvec[count].locate.size.constant;
3775 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3778 #ifdef FINAL_REG_PARM_STACK_SPACE
3779 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3782 /* If this machine requires an external definition for library
3783 functions, write one out. */
3784 assemble_external_libcall (fun);
3786 original_args_size = args_size;
3787 args_size.constant = (((args_size.constant
3788 + stack_pointer_delta
3792 - stack_pointer_delta);
3794 args_size.constant = MAX (args_size.constant,
3795 reg_parm_stack_space);
3797 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3798 args_size.constant -= reg_parm_stack_space;
3801 if (args_size.constant > current_function_outgoing_args_size)
3802 current_function_outgoing_args_size = args_size.constant;
3804 if (ACCUMULATE_OUTGOING_ARGS)
3806 /* Since the stack pointer will never be pushed, it is possible for
3807 the evaluation of a parm to clobber something we have already
3808 written to the stack. Since most function calls on RISC machines
3809 do not use the stack, this is uncommon, but must work correctly.
3811 Therefore, we save any area of the stack that was already written
3812 and that we are using. Here we set up to do this by making a new
3813 stack usage map from the old one.
3815 Another approach might be to try to reorder the argument
3816 evaluations to avoid this conflicting stack usage. */
3818 needed = args_size.constant;
3820 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3821 /* Since we will be writing into the entire argument area, the
3822 map must be allocated for its entire size, not just the part that
3823 is the responsibility of the caller. */
3824 needed += reg_parm_stack_space;
3827 #ifdef ARGS_GROW_DOWNWARD
3828 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3831 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3834 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3836 if (initial_highest_arg_in_use)
3837 memcpy (stack_usage_map, initial_stack_usage_map,
3838 initial_highest_arg_in_use);
3840 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3841 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3842 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3845 /* We must be careful to use virtual regs before they're instantiated,
3846 and real regs afterwards. Loop optimization, for example, can create
3847 new libcalls after we've instantiated the virtual regs, and if we
3848 use virtuals anyway, they won't match the rtl patterns. */
3850 if (virtuals_instantiated)
3851 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
3853 argblock = virtual_outgoing_args_rtx;
3858 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3861 /* If we push args individually in reverse order, perform stack alignment
3862 before the first push (the last arg). */
3863 if (argblock == 0 && PUSH_ARGS_REVERSED)
3864 anti_adjust_stack (GEN_INT (args_size.constant
3865 - original_args_size.constant));
3867 if (PUSH_ARGS_REVERSED)
3878 #ifdef REG_PARM_STACK_SPACE
3879 if (ACCUMULATE_OUTGOING_ARGS)
3881 /* The argument list is the property of the called routine and it
3882 may clobber it. If the fixed area has been used for previous
3883 parameters, we must save and restore it. */
3884 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3885 &low_to_save, &high_to_save);
3889 /* Push the args that need to be pushed. */
3891 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3892 are to be pushed. */
3893 for (count = 0; count < nargs; count++, argnum += inc)
3895 enum machine_mode mode = argvec[argnum].mode;
3896 rtx val = argvec[argnum].value;
3897 rtx reg = argvec[argnum].reg;
3898 int partial = argvec[argnum].partial;
3899 int lower_bound = 0, upper_bound = 0, i;
3901 if (! (reg != 0 && partial == 0))
3903 if (ACCUMULATE_OUTGOING_ARGS)
3905 /* If this is being stored into a pre-allocated, fixed-size,
3906 stack area, save any previous data at that location. */
3908 #ifdef ARGS_GROW_DOWNWARD
3909 /* stack_slot is negative, but we want to index stack_usage_map
3910 with positive values. */
3911 upper_bound = -argvec[argnum].locate.offset.constant + 1;
3912 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
3914 lower_bound = argvec[argnum].locate.offset.constant;
3915 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
3919 /* Don't worry about things in the fixed argument area;
3920 it has already been saved. */
3921 if (i < reg_parm_stack_space)
3922 i = reg_parm_stack_space;
3923 while (i < upper_bound && stack_usage_map[i] == 0)
3926 if (i < upper_bound)
3928 /* We need to make a save area. */
3930 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
3931 enum machine_mode save_mode
3932 = mode_for_size (size, MODE_INT, 1);
3934 = plus_constant (argblock,
3935 argvec[argnum].locate.offset.constant);
3937 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
3938 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3940 emit_move_insn (argvec[argnum].save_area, stack_area);
3944 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, PARM_BOUNDARY,
3945 partial, reg, 0, argblock,
3946 GEN_INT (argvec[argnum].locate.offset.constant),
3947 reg_parm_stack_space,
3948 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad));
3950 /* Now mark the segment we just used. */
3951 if (ACCUMULATE_OUTGOING_ARGS)
3952 for (i = lower_bound; i < upper_bound; i++)
3953 stack_usage_map[i] = 1;
3959 /* If we pushed args in forward order, perform stack alignment
3960 after pushing the last arg. */
3961 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3962 anti_adjust_stack (GEN_INT (args_size.constant
3963 - original_args_size.constant));
3965 if (PUSH_ARGS_REVERSED)
3970 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0, 0);
3972 /* Now load any reg parms into their regs. */
3974 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3975 are to be pushed. */
3976 for (count = 0; count < nargs; count++, argnum += inc)
3978 rtx val = argvec[argnum].value;
3979 rtx reg = argvec[argnum].reg;
3980 int partial = argvec[argnum].partial;
3982 /* Handle calls that pass values in multiple non-contiguous
3983 locations. The PA64 has examples of this for library calls. */
3984 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3985 emit_group_load (reg, val, GET_MODE_SIZE (GET_MODE (val)));
3986 else if (reg != 0 && partial == 0)
3987 emit_move_insn (reg, val);
3992 /* Any regs containing parms remain in use through the call. */
3993 for (count = 0; count < nargs; count++)
3995 rtx reg = argvec[count].reg;
3996 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3997 use_group_regs (&call_fusage, reg);
3999 use_reg (&call_fusage, reg);
4002 /* Pass the function the address in which to return a structure value. */
4003 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
4005 emit_move_insn (struct_value_rtx,
4007 force_operand (XEXP (mem_value, 0),
4009 if (GET_CODE (struct_value_rtx) == REG)
4010 use_reg (&call_fusage, struct_value_rtx);
4013 /* Don't allow popping to be deferred, since then
4014 cse'ing of library calls could delete a call and leave the pop. */
4016 valreg = (mem_value == 0 && outmode != VOIDmode
4017 ? hard_libcall_value (outmode) : NULL_RTX);
4019 /* Stack must be properly aligned now. */
4020 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4023 before_call = get_last_insn ();
4025 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4026 will set inhibit_defer_pop to that value. */
4027 /* The return type is needed to decide how many bytes the function pops.
4028 Signedness plays no role in that, so for simplicity, we pretend it's
4029 always signed. We also assume that the list of arguments passed has
4030 no impact, so we pretend it is unknown. */
4033 get_identifier (XSTR (orgfun, 0)),
4034 build_function_type (tfom, NULL_TREE),
4035 original_args_size.constant, args_size.constant,
4037 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4039 old_inhibit_defer_pop + 1, call_fusage, flags, & args_so_far);
4041 /* For calls to `setjmp', etc., inform flow.c it should complain
4042 if nonvolatile values are live. For functions that cannot return,
4043 inform flow that control does not fall through. */
4045 if (flags & (ECF_NORETURN | ECF_LONGJMP))
4047 /* The barrier note must be emitted
4048 immediately after the CALL_INSN. Some ports emit more than
4049 just a CALL_INSN above, so we must search for it here. */
4051 rtx last = get_last_insn ();
4052 while (GET_CODE (last) != CALL_INSN)
4054 last = PREV_INSN (last);
4055 /* There was no CALL_INSN? */
4056 if (last == before_call)
4060 emit_barrier_after (last);
4063 /* Now restore inhibit_defer_pop to its actual original value. */
4066 /* If call is cse'able, make appropriate pair of reg-notes around it.
4067 Test valreg so we don't crash; may safely ignore `const'
4068 if return type is void. Disable for PARALLEL return values, because
4069 we have no way to move such values into a pseudo register. */
4070 if (flags & ECF_LIBCALL_BLOCK)
4076 insns = get_insns ();
4086 if (GET_CODE (valreg) == PARALLEL)
4088 temp = gen_reg_rtx (outmode);
4089 emit_group_store (temp, valreg, outmode);
4093 temp = gen_reg_rtx (GET_MODE (valreg));
4095 /* Construct an "equal form" for the value which mentions all the
4096 arguments in order as well as the function name. */
4097 for (i = 0; i < nargs; i++)
4098 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4099 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4101 insns = get_insns ();
4104 if (flags & ECF_PURE)
4105 note = gen_rtx_EXPR_LIST (VOIDmode,
4106 gen_rtx_USE (VOIDmode,
4107 gen_rtx_MEM (BLKmode,
4108 gen_rtx_SCRATCH (VOIDmode))),
4111 emit_libcall_block (insns, temp, valreg, note);
4118 /* Copy the value to the right place. */
4119 if (outmode != VOIDmode && retval)
4125 if (value != mem_value)
4126 emit_move_insn (value, mem_value);
4128 else if (GET_CODE (valreg) == PARALLEL)
4131 value = gen_reg_rtx (outmode);
4132 emit_group_store (value, valreg, outmode);
4134 else if (value != 0)
4135 emit_move_insn (value, valreg);
4140 if (ACCUMULATE_OUTGOING_ARGS)
4142 #ifdef REG_PARM_STACK_SPACE
4144 restore_fixed_argument_area (save_area, argblock,
4145 high_to_save, low_to_save);
4148 /* If we saved any argument areas, restore them. */
4149 for (count = 0; count < nargs; count++)
4150 if (argvec[count].save_area)
4152 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4153 rtx adr = plus_constant (argblock,
4154 argvec[count].locate.offset.constant);
4155 rtx stack_area = gen_rtx_MEM (save_mode,
4156 memory_address (save_mode, adr));
4158 emit_move_insn (stack_area, argvec[count].save_area);
4161 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4162 stack_usage_map = initial_stack_usage_map;
4169 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4170 (emitting the queue unless NO_QUEUE is nonzero),
4171 for a value of mode OUTMODE,
4172 with NARGS different arguments, passed as alternating rtx values
4173 and machine_modes to convert them to.
4174 The rtx values should have been passed through protect_from_queue already.
4176 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4177 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4178 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4179 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4180 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4181 or other LCT_ value for other types of library calls. */
4184 emit_library_call VPARAMS((rtx orgfun, enum libcall_type fn_type,
4185 enum machine_mode outmode, int nargs, ...))
4188 VA_FIXEDARG (p, rtx, orgfun);
4189 VA_FIXEDARG (p, int, fn_type);
4190 VA_FIXEDARG (p, enum machine_mode, outmode);
4191 VA_FIXEDARG (p, int, nargs);
4193 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4198 /* Like emit_library_call except that an extra argument, VALUE,
4199 comes second and says where to store the result.
4200 (If VALUE is zero, this function chooses a convenient way
4201 to return the value.
4203 This function returns an rtx for where the value is to be found.
4204 If VALUE is nonzero, VALUE is returned. */
4207 emit_library_call_value VPARAMS((rtx orgfun, rtx value,
4208 enum libcall_type fn_type,
4209 enum machine_mode outmode, int nargs, ...))
4214 VA_FIXEDARG (p, rtx, orgfun);
4215 VA_FIXEDARG (p, rtx, value);
4216 VA_FIXEDARG (p, int, fn_type);
4217 VA_FIXEDARG (p, enum machine_mode, outmode);
4218 VA_FIXEDARG (p, int, nargs);
4220 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4228 /* Store a single argument for a function call
4229 into the register or memory area where it must be passed.
4230 *ARG describes the argument value and where to pass it.
4232 ARGBLOCK is the address of the stack-block for all the arguments,
4233 or 0 on a machine where arguments are pushed individually.
4235 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4236 so must be careful about how the stack is used.
4238 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4239 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4240 that we need not worry about saving and restoring the stack.
4242 FNDECL is the declaration of the function we are calling.
4244 Return nonzero if this arg should cause sibcall failure,
4248 store_one_arg (arg, argblock, flags, variable_size, reg_parm_stack_space)
4249 struct arg_data *arg;
4252 int variable_size ATTRIBUTE_UNUSED;
4253 int reg_parm_stack_space;
4255 tree pval = arg->tree_value;
4259 int i, lower_bound = 0, upper_bound = 0;
4260 int sibcall_failure = 0;
4262 if (TREE_CODE (pval) == ERROR_MARK)
4265 /* Push a new temporary level for any temporaries we make for
4269 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4271 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4272 save any previous data at that location. */
4273 if (argblock && ! variable_size && arg->stack)
4275 #ifdef ARGS_GROW_DOWNWARD
4276 /* stack_slot is negative, but we want to index stack_usage_map
4277 with positive values. */
4278 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4279 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4283 lower_bound = upper_bound - arg->locate.size.constant;
4285 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4286 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4290 upper_bound = lower_bound + arg->locate.size.constant;
4294 /* Don't worry about things in the fixed argument area;
4295 it has already been saved. */
4296 if (i < reg_parm_stack_space)
4297 i = reg_parm_stack_space;
4298 while (i < upper_bound && stack_usage_map[i] == 0)
4301 if (i < upper_bound)
4303 /* We need to make a save area. */
4304 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
4305 enum machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
4306 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
4307 rtx stack_area = gen_rtx_MEM (save_mode, adr);
4309 if (save_mode == BLKmode)
4311 tree ot = TREE_TYPE (arg->tree_value);
4312 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4313 | TYPE_QUAL_CONST));
4315 arg->save_area = assign_temp (nt, 0, 1, 1);
4316 preserve_temp_slots (arg->save_area);
4317 emit_block_move (validize_mem (arg->save_area), stack_area,
4318 expr_size (arg->tree_value),
4319 BLOCK_OP_CALL_PARM);
4323 arg->save_area = gen_reg_rtx (save_mode);
4324 emit_move_insn (arg->save_area, stack_area);
4330 /* If this isn't going to be placed on both the stack and in registers,
4331 set up the register and number of words. */
4332 if (! arg->pass_on_stack)
4334 if (flags & ECF_SIBCALL)
4335 reg = arg->tail_call_reg;
4338 partial = arg->partial;
4341 if (reg != 0 && partial == 0)
4342 /* Being passed entirely in a register. We shouldn't be called in
4346 /* If this arg needs special alignment, don't load the registers
4348 if (arg->n_aligned_regs != 0)
4351 /* If this is being passed partially in a register, we can't evaluate
4352 it directly into its stack slot. Otherwise, we can. */
4353 if (arg->value == 0)
4355 /* stack_arg_under_construction is nonzero if a function argument is
4356 being evaluated directly into the outgoing argument list and
4357 expand_call must take special action to preserve the argument list
4358 if it is called recursively.
4360 For scalar function arguments stack_usage_map is sufficient to
4361 determine which stack slots must be saved and restored. Scalar
4362 arguments in general have pass_on_stack == 0.
4364 If this argument is initialized by a function which takes the
4365 address of the argument (a C++ constructor or a C function
4366 returning a BLKmode structure), then stack_usage_map is
4367 insufficient and expand_call must push the stack around the
4368 function call. Such arguments have pass_on_stack == 1.
4370 Note that it is always safe to set stack_arg_under_construction,
4371 but this generates suboptimal code if set when not needed. */
4373 if (arg->pass_on_stack)
4374 stack_arg_under_construction++;
4376 arg->value = expand_expr (pval,
4378 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4379 ? NULL_RTX : arg->stack,
4380 VOIDmode, EXPAND_STACK_PARM);
4382 /* If we are promoting object (or for any other reason) the mode
4383 doesn't agree, convert the mode. */
4385 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4386 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4387 arg->value, arg->unsignedp);
4389 if (arg->pass_on_stack)
4390 stack_arg_under_construction--;
4393 /* Don't allow anything left on stack from computation
4394 of argument to alloca. */
4395 if (flags & ECF_MAY_BE_ALLOCA)
4396 do_pending_stack_adjust ();
4398 if (arg->value == arg->stack)
4399 /* If the value is already in the stack slot, we are done. */
4401 else if (arg->mode != BLKmode)
4405 /* Argument is a scalar, not entirely passed in registers.
4406 (If part is passed in registers, arg->partial says how much
4407 and emit_push_insn will take care of putting it there.)
4409 Push it, and if its size is less than the
4410 amount of space allocated to it,
4411 also bump stack pointer by the additional space.
4412 Note that in C the default argument promotions
4413 will prevent such mismatches. */
4415 size = GET_MODE_SIZE (arg->mode);
4416 /* Compute how much space the push instruction will push.
4417 On many machines, pushing a byte will advance the stack
4418 pointer by a halfword. */
4419 #ifdef PUSH_ROUNDING
4420 size = PUSH_ROUNDING (size);
4424 /* Compute how much space the argument should get:
4425 round up to a multiple of the alignment for arguments. */
4426 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4427 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4428 / (PARM_BOUNDARY / BITS_PER_UNIT))
4429 * (PARM_BOUNDARY / BITS_PER_UNIT));
4431 /* This isn't already where we want it on the stack, so put it there.
4432 This can either be done with push or copy insns. */
4433 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4434 PARM_BOUNDARY, partial, reg, used - size, argblock,
4435 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4436 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4438 /* Unless this is a partially-in-register argument, the argument is now
4441 arg->value = arg->stack;
4445 /* BLKmode, at least partly to be pushed. */
4447 unsigned int parm_align;
4451 /* Pushing a nonscalar.
4452 If part is passed in registers, PARTIAL says how much
4453 and emit_push_insn will take care of putting it there. */
4455 /* Round its size up to a multiple
4456 of the allocation unit for arguments. */
4458 if (arg->locate.size.var != 0)
4461 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
4465 /* PUSH_ROUNDING has no effect on us, because
4466 emit_push_insn for BLKmode is careful to avoid it. */
4467 excess = (arg->locate.size.constant
4468 - int_size_in_bytes (TREE_TYPE (pval))
4469 + partial * UNITS_PER_WORD);
4470 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4471 NULL_RTX, TYPE_MODE (sizetype), 0);
4474 /* Some types will require stricter alignment, which will be
4475 provided for elsewhere in argument layout. */
4476 parm_align = MAX (PARM_BOUNDARY, TYPE_ALIGN (TREE_TYPE (pval)));
4478 /* When an argument is padded down, the block is aligned to
4479 PARM_BOUNDARY, but the actual argument isn't. */
4480 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4482 if (arg->locate.size.var)
4483 parm_align = BITS_PER_UNIT;
4486 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4487 parm_align = MIN (parm_align, excess_align);
4491 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4493 /* emit_push_insn might not work properly if arg->value and
4494 argblock + arg->locate.offset areas overlap. */
4498 if (XEXP (x, 0) == current_function_internal_arg_pointer
4499 || (GET_CODE (XEXP (x, 0)) == PLUS
4500 && XEXP (XEXP (x, 0), 0) ==
4501 current_function_internal_arg_pointer
4502 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4504 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4505 i = INTVAL (XEXP (XEXP (x, 0), 1));
4507 /* expand_call should ensure this */
4508 if (arg->locate.offset.var || GET_CODE (size_rtx) != CONST_INT)
4511 if (arg->locate.offset.constant > i)
4513 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
4514 sibcall_failure = 1;
4516 else if (arg->locate.offset.constant < i)
4518 if (i < arg->locate.offset.constant + INTVAL (size_rtx))
4519 sibcall_failure = 1;
4524 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4525 parm_align, partial, reg, excess, argblock,
4526 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4527 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4529 /* Unless this is a partially-in-register argument, the argument is now
4532 ??? Unlike the case above, in which we want the actual
4533 address of the data, so that we can load it directly into a
4534 register, here we want the address of the stack slot, so that
4535 it's properly aligned for word-by-word copying or something
4536 like that. It's not clear that this is always correct. */
4538 arg->value = arg->stack_slot;
4541 /* Mark all slots this store used. */
4542 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
4543 && argblock && ! variable_size && arg->stack)
4544 for (i = lower_bound; i < upper_bound; i++)
4545 stack_usage_map[i] = 1;
4547 /* Once we have pushed something, pops can't safely
4548 be deferred during the rest of the arguments. */
4551 /* ANSI doesn't require a sequence point here,
4552 but PCC has one, so this will avoid some problems. */
4555 /* Free any temporary slots made in processing this argument. Show
4556 that we might have taken the address of something and pushed that
4558 preserve_temp_slots (NULL_RTX);
4562 return sibcall_failure;
4565 /* Nonzero if we do not know how to pass TYPE solely in registers.
4566 We cannot do so in the following cases:
4568 - if the type has variable size
4569 - if the type is marked as addressable (it is required to be constructed
4571 - if the padding and mode of the type is such that a copy into a register
4572 would put it into the wrong part of the register.
4574 Which padding can't be supported depends on the byte endianness.
4576 A value in a register is implicitly padded at the most significant end.
4577 On a big-endian machine, that is the lower end in memory.
4578 So a value padded in memory at the upper end can't go in a register.
4579 For a little-endian machine, the reverse is true. */
4582 default_must_pass_in_stack (mode, type)
4583 enum machine_mode mode;
4589 /* If the type has variable size... */
4590 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4593 /* If the type is marked as addressable (it is required
4594 to be constructed into the stack)... */
4595 if (TREE_ADDRESSABLE (type))
4598 /* If the padding and mode of the type is such that a copy into
4599 a register would put it into the wrong part of the register. */
4601 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
4602 && (FUNCTION_ARG_PADDING (mode, type)
4603 == (BYTES_BIG_ENDIAN ? upward : downward)))